diff options
Diffstat (limited to 'Documentation')
93 files changed, 2497 insertions, 1797 deletions
diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu index 9605dbd4b5b5..4fb76c0e8d30 100644 --- a/Documentation/ABI/testing/sysfs-devices-system-cpu +++ b/Documentation/ABI/testing/sysfs-devices-system-cpu @@ -511,10 +511,30 @@ Description: Control Symetric Multi Threading (SMT) control: Read/write interface to control SMT. Possible values: - "on" SMT is enabled - "off" SMT is disabled - "forceoff" SMT is force disabled. Cannot be changed. - "notsupported" SMT is not supported by the CPU + "on" SMT is enabled + "off" SMT is disabled + "forceoff" SMT is force disabled. Cannot be changed. + "notsupported" SMT is not supported by the CPU + "notimplemented" SMT runtime toggling is not + implemented for the architecture If control status is "forceoff" or "notsupported" writes are rejected. + +What: /sys/devices/system/cpu/cpu#/power/energy_perf_bias +Date: March 2019 +Contact: linux-pm@vger.kernel.org +Description: Intel Energy and Performance Bias Hint (EPB) + + EPB for the given CPU in a sliding scale 0 - 15, where a value + of 0 corresponds to a hint preference for highest performance + and a value of 15 corresponds to the maximum energy savings. + + In order to change the EPB value for the CPU, write either + a number in the 0 - 15 sliding scale above, or one of the + strings: "performance", "balance-performance", "normal", + "balance-power", "power" (that represent values reflected by + their meaning), to this attribute. + + This attribute is present for all online CPUs supporting the + Intel EPB feature. diff --git a/Documentation/RCU/Design/Data-Structures/Data-Structures.html b/Documentation/RCU/Design/Data-Structures/Data-Structures.html index 18f179807563..c30c1957c7e6 100644 --- a/Documentation/RCU/Design/Data-Structures/Data-Structures.html +++ b/Documentation/RCU/Design/Data-Structures/Data-Structures.html @@ -155,8 +155,7 @@ keeping lock contention under control at all tree levels regardless of the level of loading on the system. </p><p>RCU updaters wait for normal grace periods by registering -RCU callbacks, either directly via <tt>call_rcu()</tt> and -friends (namely <tt>call_rcu_bh()</tt> and <tt>call_rcu_sched()</tt>), +RCU callbacks, either directly via <tt>call_rcu()</tt> or indirectly via <tt>synchronize_rcu()</tt> and friends. RCU callbacks are represented by <tt>rcu_head</tt> structures, which are queued on <tt>rcu_data</tt> structures while they are diff --git a/Documentation/RCU/Design/Expedited-Grace-Periods/Expedited-Grace-Periods.html b/Documentation/RCU/Design/Expedited-Grace-Periods/Expedited-Grace-Periods.html index 19e7a5fb6b73..57300db4b5ff 100644 --- a/Documentation/RCU/Design/Expedited-Grace-Periods/Expedited-Grace-Periods.html +++ b/Documentation/RCU/Design/Expedited-Grace-Periods/Expedited-Grace-Periods.html @@ -56,6 +56,7 @@ sections. RCU-preempt Expedited Grace Periods</a></h2> <p> +<tt>CONFIG_PREEMPT=y</tt> kernels implement RCU-preempt. The overall flow of the handling of a given CPU by an RCU-preempt expedited grace period is shown in the following diagram: @@ -139,6 +140,7 @@ or offline, among other things. RCU-sched Expedited Grace Periods</a></h2> <p> +<tt>CONFIG_PREEMPT=n</tt> kernels implement RCU-sched. The overall flow of the handling of a given CPU by an RCU-sched expedited grace period is shown in the following diagram: @@ -146,7 +148,7 @@ expedited grace period is shown in the following diagram: <p> As with RCU-preempt, RCU-sched's -<tt>synchronize_sched_expedited()</tt> ignores offline and +<tt>synchronize_rcu_expedited()</tt> ignores offline and idle CPUs, again because they are in remotely detectable quiescent states. However, because the diff --git a/Documentation/RCU/Design/Memory-Ordering/Tree-RCU-Memory-Ordering.html b/Documentation/RCU/Design/Memory-Ordering/Tree-RCU-Memory-Ordering.html index 8d21af02b1f0..c64f8d26609f 100644 --- a/Documentation/RCU/Design/Memory-Ordering/Tree-RCU-Memory-Ordering.html +++ b/Documentation/RCU/Design/Memory-Ordering/Tree-RCU-Memory-Ordering.html @@ -34,12 +34,11 @@ Similarly, any code that happens before the beginning of a given RCU grace period is guaranteed to see the effects of all accesses following the end of that grace period that are within RCU read-side critical sections. -<p>This guarantee is particularly pervasive for <tt>synchronize_sched()</tt>, -for which RCU-sched read-side critical sections include any region +<p>Note well that RCU-sched read-side critical sections include any region of code for which preemption is disabled. Given that each individual machine instruction can be thought of as an extremely small region of preemption-disabled code, one can think of -<tt>synchronize_sched()</tt> as <tt>smp_mb()</tt> on steroids. +<tt>synchronize_rcu()</tt> as <tt>smp_mb()</tt> on steroids. <p>RCU updaters use this guarantee by splitting their updates into two phases, one of which is executed before the grace period and diff --git a/Documentation/RCU/NMI-RCU.txt b/Documentation/RCU/NMI-RCU.txt index 687777f83b23..881353fd5bff 100644 --- a/Documentation/RCU/NMI-RCU.txt +++ b/Documentation/RCU/NMI-RCU.txt @@ -81,18 +81,19 @@ currently executing on some other CPU. We therefore cannot free up any data structures used by the old NMI handler until execution of it completes on all other CPUs. -One way to accomplish this is via synchronize_sched(), perhaps as +One way to accomplish this is via synchronize_rcu(), perhaps as follows: unset_nmi_callback(); - synchronize_sched(); + synchronize_rcu(); kfree(my_nmi_data); -This works because synchronize_sched() blocks until all CPUs complete -any preemption-disabled segments of code that they were executing. -Since NMI handlers disable preemption, synchronize_sched() is guaranteed +This works because (as of v4.20) synchronize_rcu() blocks until all +CPUs complete any preemption-disabled segments of code that they were +executing. +Since NMI handlers disable preemption, synchronize_rcu() is guaranteed not to return until all ongoing NMI handlers exit. It is therefore safe -to free up the handler's data as soon as synchronize_sched() returns. +to free up the handler's data as soon as synchronize_rcu() returns. Important note: for this to work, the architecture in question must invoke nmi_enter() and nmi_exit() on NMI entry and exit, respectively. diff --git a/Documentation/RCU/UP.txt b/Documentation/RCU/UP.txt index 90ec5341ee98..53bde717017b 100644 --- a/Documentation/RCU/UP.txt +++ b/Documentation/RCU/UP.txt @@ -86,10 +86,8 @@ even on a UP system. So do not do it! Even on a UP system, the RCU infrastructure -must- respect grace periods, and -must- invoke callbacks from a known environment in which no locks are held. -It -is- safe for synchronize_sched() and synchronize_rcu_bh() to return -immediately on an UP system. It is also safe for synchronize_rcu() -to return immediately on UP systems, except when running preemptable -RCU. +Note that it -is- safe for synchronize_rcu() to return immediately on +UP systems, including !PREEMPT SMP builds running on UP systems. Quick Quiz #3: Why can't synchronize_rcu() return immediately on UP systems running preemptable RCU? diff --git a/Documentation/RCU/checklist.txt b/Documentation/RCU/checklist.txt index 6f469864d9f5..e98ff261a438 100644 --- a/Documentation/RCU/checklist.txt +++ b/Documentation/RCU/checklist.txt @@ -182,16 +182,13 @@ over a rather long period of time, but improvements are always welcome! when publicizing a pointer to a structure that can be traversed by an RCU read-side critical section. -5. If call_rcu(), or a related primitive such as call_rcu_bh(), - call_rcu_sched(), or call_srcu() is used, the callback function - will be called from softirq context. In particular, it cannot - block. +5. If call_rcu() or call_srcu() is used, the callback function will + be called from softirq context. In particular, it cannot block. -6. Since synchronize_rcu() can block, it cannot be called from - any sort of irq context. The same rule applies for - synchronize_rcu_bh(), synchronize_sched(), synchronize_srcu(), - synchronize_rcu_expedited(), synchronize_rcu_bh_expedited(), - synchronize_sched_expedite(), and synchronize_srcu_expedited(). +6. Since synchronize_rcu() can block, it cannot be called + from any sort of irq context. The same rule applies + for synchronize_srcu(), synchronize_rcu_expedited(), and + synchronize_srcu_expedited(). The expedited forms of these primitives have the same semantics as the non-expedited forms, but expediting is both expensive and @@ -212,20 +209,20 @@ over a rather long period of time, but improvements are always welcome! of the system, especially to real-time workloads running on the rest of the system. -7. If the updater uses call_rcu() or synchronize_rcu(), then the - corresponding readers must use rcu_read_lock() and - rcu_read_unlock(). If the updater uses call_rcu_bh() or - synchronize_rcu_bh(), then the corresponding readers must - use rcu_read_lock_bh() and rcu_read_unlock_bh(). If the - updater uses call_rcu_sched() or synchronize_sched(), then - the corresponding readers must disable preemption, possibly - by calling rcu_read_lock_sched() and rcu_read_unlock_sched(). - If the updater uses synchronize_srcu() or call_srcu(), then - the corresponding readers must use srcu_read_lock() and +7. As of v4.20, a given kernel implements only one RCU flavor, + which is RCU-sched for PREEMPT=n and RCU-preempt for PREEMPT=y. + If the updater uses call_rcu() or synchronize_rcu(), + then the corresponding readers my use rcu_read_lock() and + rcu_read_unlock(), rcu_read_lock_bh() and rcu_read_unlock_bh(), + or any pair of primitives that disables and re-enables preemption, + for example, rcu_read_lock_sched() and rcu_read_unlock_sched(). + If the updater uses synchronize_srcu() or call_srcu(), + then the corresponding readers must use srcu_read_lock() and srcu_read_unlock(), and with the same srcu_struct. The rules for the expedited primitives are the same as for their non-expedited counterparts. Mixing things up will result in confusion and - broken kernels. + broken kernels, and has even resulted in an exploitable security + issue. One exception to this rule: rcu_read_lock() and rcu_read_unlock() may be substituted for rcu_read_lock_bh() and rcu_read_unlock_bh() @@ -288,8 +285,7 @@ over a rather long period of time, but improvements are always welcome! d. Periodically invoke synchronize_rcu(), permitting a limited number of updates per grace period. - The same cautions apply to call_rcu_bh(), call_rcu_sched(), - call_srcu(), and kfree_rcu(). + The same cautions apply to call_srcu() and kfree_rcu(). Note that although these primitives do take action to avoid memory exhaustion when any given CPU has too many callbacks, a determined @@ -322,7 +318,7 @@ over a rather long period of time, but improvements are always welcome! 11. Any lock acquired by an RCU callback must be acquired elsewhere with softirq disabled, e.g., via spin_lock_irqsave(), - spin_lock_bh(), etc. Failing to disable irq on a given + spin_lock_bh(), etc. Failing to disable softirq on a given acquisition of that lock will result in deadlock as soon as the RCU softirq handler happens to run your RCU callback while interrupting that acquisition's critical section. @@ -335,13 +331,16 @@ over a rather long period of time, but improvements are always welcome! must use whatever locking or other synchronization is required to safely access and/or modify that data structure. - RCU callbacks are -usually- executed on the same CPU that executed - the corresponding call_rcu(), call_rcu_bh(), or call_rcu_sched(), - but are by -no- means guaranteed to be. For example, if a given - CPU goes offline while having an RCU callback pending, then that - RCU callback will execute on some surviving CPU. (If this was - not the case, a self-spawning RCU callback would prevent the - victim CPU from ever going offline.) + Do not assume that RCU callbacks will be executed on the same + CPU that executed the corresponding call_rcu() or call_srcu(). + For example, if a given CPU goes offline while having an RCU + callback pending, then that RCU callback will execute on some + surviving CPU. (If this was not the case, a self-spawning RCU + callback would prevent the victim CPU from ever going offline.) + Furthermore, CPUs designated by rcu_nocbs= might well -always- + have their RCU callbacks executed on some other CPUs, in fact, + for some real-time workloads, this is the whole point of using + the rcu_nocbs= kernel boot parameter. 13. Unlike other forms of RCU, it -is- permissible to block in an SRCU read-side critical section (demarked by srcu_read_lock() @@ -381,11 +380,11 @@ over a rather long period of time, but improvements are always welcome! SRCU's expedited primitive (synchronize_srcu_expedited()) never sends IPIs to other CPUs, so it is easier on - real-time workloads than is synchronize_rcu_expedited(), - synchronize_rcu_bh_expedited() or synchronize_sched_expedited(). + real-time workloads than is synchronize_rcu_expedited(). - Note that rcu_dereference() and rcu_assign_pointer() relate to - SRCU just as they do to other forms of RCU. + Note that rcu_assign_pointer() relates to SRCU just as it does to + other forms of RCU, but instead of rcu_dereference() you should + use srcu_dereference() in order to avoid lockdep splats. 14. The whole point of call_rcu(), synchronize_rcu(), and friends is to wait until all pre-existing readers have finished before @@ -405,6 +404,9 @@ over a rather long period of time, but improvements are always welcome! read-side critical sections. It is the responsibility of the RCU update-side primitives to deal with this. + For SRCU readers, you can use smp_mb__after_srcu_read_unlock() + immediately after an srcu_read_unlock() to get a full barrier. + 16. Use CONFIG_PROVE_LOCKING, CONFIG_DEBUG_OBJECTS_RCU_HEAD, and the __rcu sparse checks to validate your RCU code. These can help find problems as follows: @@ -428,22 +430,19 @@ over a rather long period of time, but improvements are always welcome! These debugging aids can help you find problems that are otherwise extremely difficult to spot. -17. If you register a callback using call_rcu(), call_rcu_bh(), - call_rcu_sched(), or call_srcu(), and pass in a function defined - within a loadable module, then it in necessary to wait for - all pending callbacks to be invoked after the last invocation - and before unloading that module. Note that it is absolutely - -not- sufficient to wait for a grace period! The current (say) - synchronize_rcu() implementation waits only for all previous - callbacks registered on the CPU that synchronize_rcu() is running - on, but it is -not- guaranteed to wait for callbacks registered - on other CPUs. +17. If you register a callback using call_rcu() or call_srcu(), and + pass in a function defined within a loadable module, then it in + necessary to wait for all pending callbacks to be invoked after + the last invocation and before unloading that module. Note that + it is absolutely -not- sufficient to wait for a grace period! + The current (say) synchronize_rcu() implementation is -not- + guaranteed to wait for callbacks registered on other CPUs. + Or even on the current CPU if that CPU recently went offline + and came back online. You instead need to use one of the barrier functions: o call_rcu() -> rcu_barrier() - o call_rcu_bh() -> rcu_barrier() - o call_rcu_sched() -> rcu_barrier() o call_srcu() -> srcu_barrier() However, these barrier functions are absolutely -not- guaranteed diff --git a/Documentation/RCU/rcu.txt b/Documentation/RCU/rcu.txt index 721b3e426515..c818cf65c5a9 100644 --- a/Documentation/RCU/rcu.txt +++ b/Documentation/RCU/rcu.txt @@ -52,10 +52,10 @@ o If I am running on a uniprocessor kernel, which can only do one o How can I see where RCU is currently used in the Linux kernel? Search for "rcu_read_lock", "rcu_read_unlock", "call_rcu", - "rcu_read_lock_bh", "rcu_read_unlock_bh", "call_rcu_bh", - "srcu_read_lock", "srcu_read_unlock", "synchronize_rcu", - "synchronize_net", "synchronize_srcu", and the other RCU - primitives. Or grab one of the cscope databases from: + "rcu_read_lock_bh", "rcu_read_unlock_bh", "srcu_read_lock", + "srcu_read_unlock", "synchronize_rcu", "synchronize_net", + "synchronize_srcu", and the other RCU primitives. Or grab one + of the cscope databases from: http://www.rdrop.com/users/paulmck/RCU/linuxusage/rculocktab.html diff --git a/Documentation/RCU/rcu_dereference.txt b/Documentation/RCU/rcu_dereference.txt index ab96227bad42..bf699e8cfc75 100644 --- a/Documentation/RCU/rcu_dereference.txt +++ b/Documentation/RCU/rcu_dereference.txt @@ -351,3 +351,106 @@ garbage values. In short, rcu_dereference() is -not- optional when you are going to dereference the resulting pointer. + + +WHICH MEMBER OF THE rcu_dereference() FAMILY SHOULD YOU USE? + +First, please avoid using rcu_dereference_raw() and also please avoid +using rcu_dereference_check() and rcu_dereference_protected() with a +second argument with a constant value of 1 (or true, for that matter). +With that caution out of the way, here is some guidance for which +member of the rcu_dereference() to use in various situations: + +1. If the access needs to be within an RCU read-side critical + section, use rcu_dereference(). With the new consolidated + RCU flavors, an RCU read-side critical section is entered + using rcu_read_lock(), anything that disables bottom halves, + anything that disables interrupts, or anything that disables + preemption. + +2. If the access might be within an RCU read-side critical section + on the one hand, or protected by (say) my_lock on the other, + use rcu_dereference_check(), for example: + + p1 = rcu_dereference_check(p->rcu_protected_pointer, + lockdep_is_held(&my_lock)); + + +3. If the access might be within an RCU read-side critical section + on the one hand, or protected by either my_lock or your_lock on + the other, again use rcu_dereference_check(), for example: + + p1 = rcu_dereference_check(p->rcu_protected_pointer, + lockdep_is_held(&my_lock) || + lockdep_is_held(&your_lock)); + +4. If the access is on the update side, so that it is always protected + by my_lock, use rcu_dereference_protected(): + + p1 = rcu_dereference_protected(p->rcu_protected_pointer, + lockdep_is_held(&my_lock)); + + This can be extended to handle multiple locks as in #3 above, + and both can be extended to check other conditions as well. + +5. If the protection is supplied by the caller, and is thus unknown + to this code, that is the rare case when rcu_dereference_raw() + is appropriate. In addition, rcu_dereference_raw() might be + appropriate when the lockdep expression would be excessively + complex, except that a better approach in that case might be to + take a long hard look at your synchronization design. Still, + there are data-locking cases where any one of a very large number + of locks or reference counters suffices to protect the pointer, + so rcu_dereference_raw() does have its place. + + However, its place is probably quite a bit smaller than one + might expect given the number of uses in the current kernel. + Ditto for its synonym, rcu_dereference_check( ... , 1), and + its close relative, rcu_dereference_protected(... , 1). + + +SPARSE CHECKING OF RCU-PROTECTED POINTERS + +The sparse static-analysis tool checks for direct access to RCU-protected +pointers, which can result in "interesting" bugs due to compiler +optimizations involving invented loads and perhaps also load tearing. +For example, suppose someone mistakenly does something like this: + + p = q->rcu_protected_pointer; + do_something_with(p->a); + do_something_else_with(p->b); + +If register pressure is high, the compiler might optimize "p" out +of existence, transforming the code to something like this: + + do_something_with(q->rcu_protected_pointer->a); + do_something_else_with(q->rcu_protected_pointer->b); + +This could fatally disappoint your code if q->rcu_protected_pointer +changed in the meantime. Nor is this a theoretical problem: Exactly +this sort of bug cost Paul E. McKenney (and several of his innocent +colleagues) a three-day weekend back in the early 1990s. + +Load tearing could of course result in dereferencing a mashup of a pair +of pointers, which also might fatally disappoint your code. + +These problems could have been avoided simply by making the code instead +read as follows: + + p = rcu_dereference(q->rcu_protected_pointer); + do_something_with(p->a); + do_something_else_with(p->b); + +Unfortunately, these sorts of bugs can be extremely hard to spot during +review. This is where the sparse tool comes into play, along with the +"__rcu" marker. If you mark a pointer declaration, whether in a structure +or as a formal parameter, with "__rcu", which tells sparse to complain if +this pointer is accessed directly. It will also cause sparse to complain +if a pointer not marked with "__rcu" is accessed using rcu_dereference() +and friends. For example, ->rcu_protected_pointer might be declared as +follows: + + struct foo __rcu *rcu_protected_pointer; + +Use of "__rcu" is opt-in. If you choose not to use it, then you should +ignore the sparse warnings. diff --git a/Documentation/RCU/rcubarrier.txt b/Documentation/RCU/rcubarrier.txt index 5d7759071a3e..a2782df69732 100644 --- a/Documentation/RCU/rcubarrier.txt +++ b/Documentation/RCU/rcubarrier.txt @@ -83,16 +83,15 @@ Pseudo-code using rcu_barrier() is as follows: 2. Execute rcu_barrier(). 3. Allow the module to be unloaded. -There are also rcu_barrier_bh(), rcu_barrier_sched(), and srcu_barrier() -functions for the other flavors of RCU, and you of course must match -the flavor of rcu_barrier() with that of call_rcu(). If your module -uses multiple flavors of call_rcu(), then it must also use multiple +There is also an srcu_barrier() function for SRCU, and you of course +must match the flavor of rcu_barrier() with that of call_rcu(). If your +module uses multiple flavors of call_rcu(), then it must also use multiple flavors of rcu_barrier() when unloading that module. For example, if -it uses call_rcu_bh(), call_srcu() on srcu_struct_1, and call_srcu() on +it uses call_rcu(), call_srcu() on srcu_struct_1, and call_srcu() on srcu_struct_2(), then the following three lines of code will be required when unloading: - 1 rcu_barrier_bh(); + 1 rcu_barrier(); 2 srcu_barrier(&srcu_struct_1); 3 srcu_barrier(&srcu_struct_2); @@ -185,12 +184,12 @@ module invokes call_rcu() from timers, you will need to first cancel all the timers, and only then invoke rcu_barrier() to wait for any remaining RCU callbacks to complete. -Of course, if you module uses call_rcu_bh(), you will need to invoke -rcu_barrier_bh() before unloading. Similarly, if your module uses -call_rcu_sched(), you will need to invoke rcu_barrier_sched() before -unloading. If your module uses call_rcu(), call_rcu_bh(), -and- -call_rcu_sched(), then you will need to invoke each of rcu_barrier(), -rcu_barrier_bh(), and rcu_barrier_sched(). +Of course, if you module uses call_rcu(), you will need to invoke +rcu_barrier() before unloading. Similarly, if your module uses +call_srcu(), you will need to invoke srcu_barrier() before unloading, +and on the same srcu_struct structure. If your module uses call_rcu() +-and- call_srcu(), then you will need to invoke rcu_barrier() -and- +srcu_barrier(). Implementing rcu_barrier() @@ -223,8 +222,8 @@ shown below. Note that the final "1" in on_each_cpu()'s argument list ensures that all the calls to rcu_barrier_func() will have completed before on_each_cpu() returns. Line 9 then waits for the completion. -This code was rewritten in 2008 to support rcu_barrier_bh() and -rcu_barrier_sched() in addition to the original rcu_barrier(). +This code was rewritten in 2008 and several times thereafter, but this +still gives the general idea. The rcu_barrier_func() runs on each CPU, where it invokes call_rcu() to post an RCU callback, as follows: diff --git a/Documentation/RCU/whatisRCU.txt b/Documentation/RCU/whatisRCU.txt index 1ace20815bb1..981651a8b65d 100644 --- a/Documentation/RCU/whatisRCU.txt +++ b/Documentation/RCU/whatisRCU.txt @@ -310,7 +310,7 @@ reader, updater, and reclaimer. rcu_assign_pointer() - +--------+ + +--------+ +---------------------->| reader |---------+ | +--------+ | | | | @@ -318,12 +318,12 @@ reader, updater, and reclaimer. | | | rcu_read_lock() | | | rcu_read_unlock() | rcu_dereference() | | - +---------+ | | - | updater |<---------------------+ | - +---------+ V + +---------+ | | + | updater |<----------------+ | + +---------+ V | +-----------+ +----------------------------------->| reclaimer | - +-----------+ + +-----------+ Defer: synchronize_rcu() & call_rcu() diff --git a/Documentation/acpi/aml-debugger.txt b/Documentation/acpi/aml-debugger.txt deleted file mode 100644 index 75ebeb64ab29..000000000000 --- a/Documentation/acpi/aml-debugger.txt +++ /dev/null @@ -1,66 +0,0 @@ -The AML Debugger - -Copyright (C) 2016, Intel Corporation -Author: Lv Zheng <lv.zheng@intel.com> - - -This document describes the usage of the AML debugger embedded in the Linux -kernel. - -1. Build the debugger - - The following kernel configuration items are required to enable the AML - debugger interface from the Linux kernel: - - CONFIG_ACPI_DEBUGGER=y - CONFIG_ACPI_DEBUGGER_USER=m - - The userspace utilities can be built from the kernel source tree using - the following commands: - - $ cd tools - $ make acpi - - The resultant userspace tool binary is then located at: - - tools/power/acpi/acpidbg - - It can be installed to system directories by running "make install" (as a - sufficiently privileged user). - -2. Start the userspace debugger interface - - After booting the kernel with the debugger built-in, the debugger can be - started by using the following commands: - - # mount -t debugfs none /sys/kernel/debug - # modprobe acpi_dbg - # tools/power/acpi/acpidbg - - That spawns the interactive AML debugger environment where you can execute - debugger commands. - - The commands are documented in the "ACPICA Overview and Programmer Reference" - that can be downloaded from - - https://acpica.org/documentation - - The detailed debugger commands reference is located in Chapter 12 "ACPICA - Debugger Reference". The "help" command can be used for a quick reference. - -3. Stop the userspace debugger interface - - The interactive debugger interface can be closed by pressing Ctrl+C or using - the "quit" or "exit" commands. When finished, unload the module with: - - # rmmod acpi_dbg - - The module unloading may fail if there is an acpidbg instance running. - -4. Run the debugger in a script - - It may be useful to run the AML debugger in a test script. "acpidbg" supports - this in a special "batch" mode. For example, the following command outputs - the entire ACPI namespace: - - # acpidbg -b "namespace" diff --git a/Documentation/acpi/apei/output_format.txt b/Documentation/acpi/apei/output_format.txt deleted file mode 100644 index 0c49c197c47a..000000000000 --- a/Documentation/acpi/apei/output_format.txt +++ /dev/null @@ -1,147 +0,0 @@ - APEI output format - ~~~~~~~~~~~~~~~~~~ - -APEI uses printk as hardware error reporting interface, the output -format is as follow. - -<error record> := -APEI generic hardware error status -severity: <integer>, <severity string> -section: <integer>, severity: <integer>, <severity string> -flags: <integer> -<section flags strings> -fru_id: <uuid string> -fru_text: <string> -section_type: <section type string> -<section data> - -<severity string>* := recoverable | fatal | corrected | info - -<section flags strings># := -[primary][, containment warning][, reset][, threshold exceeded]\ -[, resource not accessible][, latent error] - -<section type string> := generic processor error | memory error | \ -PCIe error | unknown, <uuid string> - -<section data> := -<generic processor section data> | <memory section data> | \ -<pcie section data> | <null> - -<generic processor section data> := -[processor_type: <integer>, <proc type string>] -[processor_isa: <integer>, <proc isa string>] -[error_type: <integer> -<proc error type strings>] -[operation: <integer>, <proc operation string>] -[flags: <integer> -<proc flags strings>] -[level: <integer>] -[version_info: <integer>] -[processor_id: <integer>] -[target_address: <integer>] -[requestor_id: <integer>] -[responder_id: <integer>] -[IP: <integer>] - -<proc type string>* := IA32/X64 | IA64 - -<proc isa string>* := IA32 | IA64 | X64 - -<processor error type strings># := -[cache error][, TLB error][, bus error][, micro-architectural error] - -<proc operation string>* := unknown or generic | data read | data write | \ -instruction execution - -<proc flags strings># := -[restartable][, precise IP][, overflow][, corrected] - -<memory section data> := -[error_status: <integer>] -[physical_address: <integer>] -[physical_address_mask: <integer>] -[node: <integer>] -[card: <integer>] -[module: <integer>] -[bank: <integer>] -[device: <integer>] -[row: <integer>] -[column: <integer>] -[bit_position: <integer>] -[requestor_id: <integer>] -[responder_id: <integer>] -[target_id: <integer>] -[error_type: <integer>, <mem error type string>] - -<mem error type string>* := -unknown | no error | single-bit ECC | multi-bit ECC | \ -single-symbol chipkill ECC | multi-symbol chipkill ECC | master abort | \ -target abort | parity error | watchdog timeout | invalid address | \ -mirror Broken | memory sparing | scrub corrected error | \ -scrub uncorrected error - -<pcie section data> := -[port_type: <integer>, <pcie port type string>] -[version: <integer>.<integer>] -[command: <integer>, status: <integer>] -[device_id: <integer>:<integer>:<integer>.<integer> -slot: <integer> -secondary_bus: <integer> -vendor_id: <integer>, device_id: <integer> -class_code: <integer>] -[serial number: <integer>, <integer>] -[bridge: secondary_status: <integer>, control: <integer>] -[aer_status: <integer>, aer_mask: <integer> -<aer status string> -[aer_uncor_severity: <integer>] -aer_layer=<aer layer string>, aer_agent=<aer agent string> -aer_tlp_header: <integer> <integer> <integer> <integer>] - -<pcie port type string>* := PCIe end point | legacy PCI end point | \ -unknown | unknown | root port | upstream switch port | \ -downstream switch port | PCIe to PCI/PCI-X bridge | \ -PCI/PCI-X to PCIe bridge | root complex integrated endpoint device | \ -root complex event collector - -if section severity is fatal or recoverable -<aer status string># := -unknown | unknown | unknown | unknown | Data Link Protocol | \ -unknown | unknown | unknown | unknown | unknown | unknown | unknown | \ -Poisoned TLP | Flow Control Protocol | Completion Timeout | \ -Completer Abort | Unexpected Completion | Receiver Overflow | \ -Malformed TLP | ECRC | Unsupported Request -else -<aer status string># := -Receiver Error | unknown | unknown | unknown | unknown | unknown | \ -Bad TLP | Bad DLLP | RELAY_NUM Rollover | unknown | unknown | unknown | \ -Replay Timer Timeout | Advisory Non-Fatal -fi - -<aer layer string> := -Physical Layer | Data Link Layer | Transaction Layer - -<aer agent string> := -Receiver ID | Requester ID | Completer ID | Transmitter ID - -Where, [] designate corresponding content is optional - -All <field string> description with * has the following format: - -field: <integer>, <field string> - -Where value of <integer> should be the position of "string" in <field -string> description. Otherwise, <field string> will be "unknown". - -All <field strings> description with # has the following format: - -field: <integer> -<field strings> - -Where each string in <fields strings> corresponding to one set bit of -<integer>. The bit position is the position of "string" in <field -strings> description. - -For more detailed explanation of every field, please refer to UEFI -specification version 2.3 or later, section Appendix N: Common -Platform Error Record. diff --git a/Documentation/acpi/i2c-muxes.txt b/Documentation/acpi/i2c-muxes.txt deleted file mode 100644 index 9fcc4f0b885e..000000000000 --- a/Documentation/acpi/i2c-muxes.txt +++ /dev/null @@ -1,58 +0,0 @@ -ACPI I2C Muxes --------------- - -Describing an I2C device hierarchy that includes I2C muxes requires an ACPI -Device () scope per mux channel. - -Consider this topology: - -+------+ +------+ -| SMB1 |-->| MUX0 |--CH00--> i2c client A (0x50) -| | | 0x70 |--CH01--> i2c client B (0x50) -+------+ +------+ - -which corresponds to the following ASL: - -Device (SMB1) -{ - Name (_HID, ...) - Device (MUX0) - { - Name (_HID, ...) - Name (_CRS, ResourceTemplate () { - I2cSerialBus (0x70, ControllerInitiated, I2C_SPEED, - AddressingMode7Bit, "^SMB1", 0x00, - ResourceConsumer,,) - } - - Device (CH00) - { - Name (_ADR, 0) - - Device (CLIA) - { - Name (_HID, ...) - Name (_CRS, ResourceTemplate () { - I2cSerialBus (0x50, ControllerInitiated, I2C_SPEED, - AddressingMode7Bit, "^CH00", 0x00, - ResourceConsumer,,) - } - } - } - - Device (CH01) - { - Name (_ADR, 1) - - Device (CLIB) - { - Name (_HID, ...) - Name (_CRS, ResourceTemplate () { - I2cSerialBus (0x50, ControllerInitiated, I2C_SPEED, - AddressingMode7Bit, "^CH01", 0x00, - ResourceConsumer,,) - } - } - } - } -} diff --git a/Documentation/acpi/initrd_table_override.txt b/Documentation/acpi/initrd_table_override.txt deleted file mode 100644 index 30437a6db373..000000000000 --- a/Documentation/acpi/initrd_table_override.txt +++ /dev/null @@ -1,111 +0,0 @@ -Upgrading ACPI tables via initrd -================================ - -1) Introduction (What is this about) -2) What is this for -3) How does it work -4) References (Where to retrieve userspace tools) - -1) What is this about ---------------------- - -If the ACPI_TABLE_UPGRADE compile option is true, it is possible to -upgrade the ACPI execution environment that is defined by the ACPI tables -via upgrading the ACPI tables provided by the BIOS with an instrumented, -modified, more recent version one, or installing brand new ACPI tables. - -When building initrd with kernel in a single image, option -ACPI_TABLE_OVERRIDE_VIA_BUILTIN_INITRD should also be true for this -feature to work. - -For a full list of ACPI tables that can be upgraded/installed, take a look -at the char *table_sigs[MAX_ACPI_SIGNATURE]; definition in -drivers/acpi/tables.c. -All ACPI tables iasl (Intel's ACPI compiler and disassembler) knows should -be overridable, except: - - ACPI_SIG_RSDP (has a signature of 6 bytes) - - ACPI_SIG_FACS (does not have an ordinary ACPI table header) -Both could get implemented as well. - - -2) What is this for -------------------- - -Complain to your platform/BIOS vendor if you find a bug which is so severe -that a workaround is not accepted in the Linux kernel. And this facility -allows you to upgrade the buggy tables before your platform/BIOS vendor -releases an upgraded BIOS binary. - -This facility can be used by platform/BIOS vendors to provide a Linux -compatible environment without modifying the underlying platform firmware. - -This facility also provides a powerful feature to easily debug and test -ACPI BIOS table compatibility with the Linux kernel by modifying old -platform provided ACPI tables or inserting new ACPI tables. - -It can and should be enabled in any kernel because there is no functional -change with not instrumented initrds. - - -3) How does it work -------------------- - -# Extract the machine's ACPI tables: -cd /tmp -acpidump >acpidump -acpixtract -a acpidump -# Disassemble, modify and recompile them: -iasl -d *.dat -# For example add this statement into a _PRT (PCI Routing Table) function -# of the DSDT: -Store("HELLO WORLD", debug) -# And increase the OEM Revision. For example, before modification: -DefinitionBlock ("DSDT.aml", "DSDT", 2, "INTEL ", "TEMPLATE", 0x00000000) -# After modification: -DefinitionBlock ("DSDT.aml", "DSDT", 2, "INTEL ", "TEMPLATE", 0x00000001) -iasl -sa dsdt.dsl -# Add the raw ACPI tables to an uncompressed cpio archive. -# They must be put into a /kernel/firmware/acpi directory inside the cpio -# archive. Note that if the table put here matches a platform table -# (similar Table Signature, and similar OEMID, and similar OEM Table ID) -# with a more recent OEM Revision, the platform table will be upgraded by -# this table. If the table put here doesn't match a platform table -# (dissimilar Table Signature, or dissimilar OEMID, or dissimilar OEM Table -# ID), this table will be appended. -mkdir -p kernel/firmware/acpi -cp dsdt.aml kernel/firmware/acpi -# A maximum of "NR_ACPI_INITRD_TABLES (64)" tables are currently allowed -# (see osl.c): -iasl -sa facp.dsl -iasl -sa ssdt1.dsl -cp facp.aml kernel/firmware/acpi -cp ssdt1.aml kernel/firmware/acpi -# The uncompressed cpio archive must be the first. Other, typically -# compressed cpio archives, must be concatenated on top of the uncompressed -# one. Following command creates the uncompressed cpio archive and -# concatenates the original initrd on top: -find kernel | cpio -H newc --create > /boot/instrumented_initrd -cat /boot/initrd >>/boot/instrumented_initrd -# reboot with increased acpi debug level, e.g. boot params: -acpi.debug_level=0x2 acpi.debug_layer=0xFFFFFFFF -# and check your syslog: -[ 1.268089] ACPI: PCI Interrupt Routing Table [\_SB_.PCI0._PRT] -[ 1.272091] [ACPI Debug] String [0x0B] "HELLO WORLD" - -iasl is able to disassemble and recompile quite a lot different, -also static ACPI tables. - - -4) Where to retrieve userspace tools ------------------------------------- - -iasl and acpixtract are part of Intel's ACPICA project: -http://acpica.org/ -and should be packaged by distributions (for example in the acpica package -on SUSE). - -acpidump can be found in Len Browns pmtools: -ftp://kernel.org/pub/linux/kernel/people/lenb/acpi/utils/pmtools/acpidump -This tool is also part of the acpica package on SUSE. -Alternatively, used ACPI tables can be retrieved via sysfs in latest kernels: -/sys/firmware/acpi/tables diff --git a/Documentation/acpi/method-customizing.txt b/Documentation/acpi/method-customizing.txt deleted file mode 100644 index 7235da975f23..000000000000 --- a/Documentation/acpi/method-customizing.txt +++ /dev/null @@ -1,73 +0,0 @@ -Linux ACPI Custom Control Method How To -======================================= - -Written by Zhang Rui <rui.zhang@intel.com> - - -Linux supports customizing ACPI control methods at runtime. - -Users can use this to -1. override an existing method which may not work correctly, - or just for debugging purposes. -2. insert a completely new method in order to create a missing - method such as _OFF, _ON, _STA, _INI, etc. -For these cases, it is far simpler to dynamically install a single -control method rather than override the entire DSDT, because kernel -rebuild/reboot is not needed and test result can be got in minutes. - -Note: Only ACPI METHOD can be overridden, any other object types like - "Device", "OperationRegion", are not recognized. Methods - declared inside scope operators are also not supported. -Note: The same ACPI control method can be overridden for many times, - and it's always the latest one that used by Linux/kernel. -Note: To get the ACPI debug object output (Store (AAAA, Debug)), - please run "echo 1 > /sys/module/acpi/parameters/aml_debug_output". - -1. override an existing method - a) get the ACPI table via ACPI sysfs I/F. e.g. to get the DSDT, - just run "cat /sys/firmware/acpi/tables/DSDT > /tmp/dsdt.dat" - b) disassemble the table by running "iasl -d dsdt.dat". - c) rewrite the ASL code of the method and save it in a new file, - d) package the new file (psr.asl) to an ACPI table format. - Here is an example of a customized \_SB._AC._PSR method, - - DefinitionBlock ("", "SSDT", 1, "", "", 0x20080715) - { - Method (\_SB_.AC._PSR, 0, NotSerialized) - { - Store ("In AC _PSR", Debug) - Return (ACON) - } - } - Note that the full pathname of the method in ACPI namespace - should be used. - e) assemble the file to generate the AML code of the method. - e.g. "iasl -vw 6084 psr.asl" (psr.aml is generated as a result) - If parameter "-vw 6084" is not supported by your iASL compiler, - please try a newer version. - f) mount debugfs by "mount -t debugfs none /sys/kernel/debug" - g) override the old method via the debugfs by running - "cat /tmp/psr.aml > /sys/kernel/debug/acpi/custom_method" - -2. insert a new method - This is easier than overriding an existing method. - We just need to create the ASL code of the method we want to - insert and then follow the step c) ~ g) in section 1. - -3. undo your changes - The "undo" operation is not supported for a new inserted method - right now, i.e. we can not remove a method currently. - For an overridden method, in order to undo your changes, please - save a copy of the method original ASL code in step c) section 1, - and redo step c) ~ g) to override the method with the original one. - - -Note: We can use a kernel with multiple custom ACPI method running, - But each individual write to debugfs can implement a SINGLE - method override. i.e. if we want to insert/override multiple - ACPI methods, we need to redo step c) ~ g) for multiple times. - -Note: Be aware that root can mis-use this driver to modify arbitrary - memory and gain additional rights, if root's privileges got - restricted (for example if root is not allowed to load additional - modules after boot). diff --git a/Documentation/acpi/method-tracing.txt b/Documentation/acpi/method-tracing.txt deleted file mode 100644 index 0aba14c8f459..000000000000 --- a/Documentation/acpi/method-tracing.txt +++ /dev/null @@ -1,192 +0,0 @@ -ACPICA Trace Facility - -Copyright (C) 2015, Intel Corporation -Author: Lv Zheng <lv.zheng@intel.com> - - -Abstract: - -This document describes the functions and the interfaces of the method -tracing facility. - -1. Functionalities and usage examples: - - ACPICA provides method tracing capability. And two functions are - currently implemented using this capability. - - A. Log reducer - ACPICA subsystem provides debugging outputs when CONFIG_ACPI_DEBUG is - enabled. The debugging messages which are deployed via - ACPI_DEBUG_PRINT() macro can be reduced at 2 levels - per-component - level (known as debug layer, configured via - /sys/module/acpi/parameters/debug_layer) and per-type level (known as - debug level, configured via /sys/module/acpi/parameters/debug_level). - - But when the particular layer/level is applied to the control method - evaluations, the quantity of the debugging outputs may still be too - large to be put into the kernel log buffer. The idea thus is worked out - to only enable the particular debug layer/level (normally more detailed) - logs when the control method evaluation is started, and disable the - detailed logging when the control method evaluation is stopped. - - The following command examples illustrate the usage of the "log reducer" - functionality: - a. Filter out the debug layer/level matched logs when control methods - are being evaluated: - # cd /sys/module/acpi/parameters - # echo "0xXXXXXXXX" > trace_debug_layer - # echo "0xYYYYYYYY" > trace_debug_level - # echo "enable" > trace_state - b. Filter out the debug layer/level matched logs when the specified - control method is being evaluated: - # cd /sys/module/acpi/parameters - # echo "0xXXXXXXXX" > trace_debug_layer - # echo "0xYYYYYYYY" > trace_debug_level - # echo "\PPPP.AAAA.TTTT.HHHH" > trace_method_name - # echo "method" > /sys/module/acpi/parameters/trace_state - c. Filter out the debug layer/level matched logs when the specified - control method is being evaluated for the first time: - # cd /sys/module/acpi/parameters - # echo "0xXXXXXXXX" > trace_debug_layer - # echo "0xYYYYYYYY" > trace_debug_level - # echo "\PPPP.AAAA.TTTT.HHHH" > trace_method_name - # echo "method-once" > /sys/module/acpi/parameters/trace_state - Where: - 0xXXXXXXXX/0xYYYYYYYY: Refer to Documentation/acpi/debug.txt for - possible debug layer/level masking values. - \PPPP.AAAA.TTTT.HHHH: Full path of a control method that can be found - in the ACPI namespace. It needn't be an entry - of a control method evaluation. - - B. AML tracer - - There are special log entries added by the method tracing facility at - the "trace points" the AML interpreter starts/stops to execute a control - method, or an AML opcode. Note that the format of the log entries are - subject to change: - [ 0.186427] exdebug-0398 ex_trace_point : Method Begin [0xf58394d8:\_SB.PCI0.LPCB.ECOK] execution. - [ 0.186630] exdebug-0398 ex_trace_point : Opcode Begin [0xf5905c88:If] execution. - [ 0.186820] exdebug-0398 ex_trace_point : Opcode Begin [0xf5905cc0:LEqual] execution. - [ 0.187010] exdebug-0398 ex_trace_point : Opcode Begin [0xf5905a20:-NamePath-] execution. - [ 0.187214] exdebug-0398 ex_trace_point : Opcode End [0xf5905a20:-NamePath-] execution. - [ 0.187407] exdebug-0398 ex_trace_point : Opcode Begin [0xf5905f60:One] execution. - [ 0.187594] exdebug-0398 ex_trace_point : Opcode End [0xf5905f60:One] execution. - [ 0.187789] exdebug-0398 ex_trace_point : Opcode End [0xf5905cc0:LEqual] execution. - [ 0.187980] exdebug-0398 ex_trace_point : Opcode Begin [0xf5905cc0:Return] execution. - [ 0.188146] exdebug-0398 ex_trace_point : Opcode Begin [0xf5905f60:One] execution. - [ 0.188334] exdebug-0398 ex_trace_point : Opcode End [0xf5905f60:One] execution. - [ 0.188524] exdebug-0398 ex_trace_point : Opcode End [0xf5905cc0:Return] execution. - [ 0.188712] exdebug-0398 ex_trace_point : Opcode End [0xf5905c88:If] execution. - [ 0.188903] exdebug-0398 ex_trace_point : Method End [0xf58394d8:\_SB.PCI0.LPCB.ECOK] execution. - - Developers can utilize these special log entries to track the AML - interpretion, thus can aid issue debugging and performance tuning. Note - that, as the "AML tracer" logs are implemented via ACPI_DEBUG_PRINT() - macro, CONFIG_ACPI_DEBUG is also required to be enabled for enabling - "AML tracer" logs. - - The following command examples illustrate the usage of the "AML tracer" - functionality: - a. Filter out the method start/stop "AML tracer" logs when control - methods are being evaluated: - # cd /sys/module/acpi/parameters - # echo "0x80" > trace_debug_layer - # echo "0x10" > trace_debug_level - # echo "enable" > trace_state - b. Filter out the method start/stop "AML tracer" when the specified - control method is being evaluated: - # cd /sys/module/acpi/parameters - # echo "0x80" > trace_debug_layer - # echo "0x10" > trace_debug_level - # echo "\PPPP.AAAA.TTTT.HHHH" > trace_method_name - # echo "method" > trace_state - c. Filter out the method start/stop "AML tracer" logs when the specified - control method is being evaluated for the first time: - # cd /sys/module/acpi/parameters - # echo "0x80" > trace_debug_layer - # echo "0x10" > trace_debug_level - # echo "\PPPP.AAAA.TTTT.HHHH" > trace_method_name - # echo "method-once" > trace_state - d. Filter out the method/opcode start/stop "AML tracer" when the - specified control method is being evaluated: - # cd /sys/module/acpi/parameters - # echo "0x80" > trace_debug_layer - # echo "0x10" > trace_debug_level - # echo "\PPPP.AAAA.TTTT.HHHH" > trace_method_name - # echo "opcode" > trace_state - e. Filter out the method/opcode start/stop "AML tracer" when the - specified control method is being evaluated for the first time: - # cd /sys/module/acpi/parameters - # echo "0x80" > trace_debug_layer - # echo "0x10" > trace_debug_level - # echo "\PPPP.AAAA.TTTT.HHHH" > trace_method_name - # echo "opcode-opcode" > trace_state - - Note that all above method tracing facility related module parameters can - be used as the boot parameters, for example: - acpi.trace_debug_layer=0x80 acpi.trace_debug_level=0x10 \ - acpi.trace_method_name=\_SB.LID0._LID acpi.trace_state=opcode-once - -2. Interface descriptions: - - All method tracing functions can be configured via ACPI module - parameters that are accessible at /sys/module/acpi/parameters/: - - trace_method_name - The full path of the AML method that the user wants to trace. - Note that the full path shouldn't contain the trailing "_"s in its - name segments but may contain "\" to form an absolute path. - - trace_debug_layer - The temporary debug_layer used when the tracing feature is enabled. - Using ACPI_EXECUTER (0x80) by default, which is the debug_layer - used to match all "AML tracer" logs. - - trace_debug_level - The temporary debug_level used when the tracing feature is enabled. - Using ACPI_LV_TRACE_POINT (0x10) by default, which is the - debug_level used to match all "AML tracer" logs. - - trace_state - The status of the tracing feature. - Users can enable/disable this debug tracing feature by executing - the following command: - # echo string > /sys/module/acpi/parameters/trace_state - Where "string" should be one of the following: - "disable" - Disable the method tracing feature. - "enable" - Enable the method tracing feature. - ACPICA debugging messages matching - "trace_debug_layer/trace_debug_level" during any method - execution will be logged. - "method" - Enable the method tracing feature. - ACPICA debugging messages matching - "trace_debug_layer/trace_debug_level" during method execution - of "trace_method_name" will be logged. - "method-once" - Enable the method tracing feature. - ACPICA debugging messages matching - "trace_debug_layer/trace_debug_level" during method execution - of "trace_method_name" will be logged only once. - "opcode" - Enable the method tracing feature. - ACPICA debugging messages matching - "trace_debug_layer/trace_debug_level" during method/opcode - execution of "trace_method_name" will be logged. - "opcode-once" - Enable the method tracing feature. - ACPICA debugging messages matching - "trace_debug_layer/trace_debug_level" during method/opcode - execution of "trace_method_name" will be logged only once. - Note that, the difference between the "enable" and other feature - enabling options are: - 1. When "enable" is specified, since - "trace_debug_layer/trace_debug_level" shall apply to all control - method evaluations, after configuring "trace_state" to "enable", - "trace_method_name" will be reset to NULL. - 2. When "method/opcode" is specified, if - "trace_method_name" is NULL when "trace_state" is configured to - these options, the "trace_debug_layer/trace_debug_level" will - apply to all control method evaluations. diff --git a/Documentation/acpi/ssdt-overlays.txt b/Documentation/acpi/ssdt-overlays.txt deleted file mode 100644 index 5ae13f161ea2..000000000000 --- a/Documentation/acpi/ssdt-overlays.txt +++ /dev/null @@ -1,172 +0,0 @@ - -In order to support ACPI open-ended hardware configurations (e.g. development -boards) we need a way to augment the ACPI configuration provided by the firmware -image. A common example is connecting sensors on I2C / SPI buses on development -boards. - -Although this can be accomplished by creating a kernel platform driver or -recompiling the firmware image with updated ACPI tables, neither is practical: -the former proliferates board specific kernel code while the latter requires -access to firmware tools which are often not publicly available. - -Because ACPI supports external references in AML code a more practical -way to augment firmware ACPI configuration is by dynamically loading -user defined SSDT tables that contain the board specific information. - -For example, to enumerate a Bosch BMA222E accelerometer on the I2C bus of the -Minnowboard MAX development board exposed via the LSE connector [1], the -following ASL code can be used: - -DefinitionBlock ("minnowmax.aml", "SSDT", 1, "Vendor", "Accel", 0x00000003) -{ - External (\_SB.I2C6, DeviceObj) - - Scope (\_SB.I2C6) - { - Device (STAC) - { - Name (_ADR, Zero) - Name (_HID, "BMA222E") - - Method (_CRS, 0, Serialized) - { - Name (RBUF, ResourceTemplate () - { - I2cSerialBus (0x0018, ControllerInitiated, 0x00061A80, - AddressingMode7Bit, "\\_SB.I2C6", 0x00, - ResourceConsumer, ,) - GpioInt (Edge, ActiveHigh, Exclusive, PullDown, 0x0000, - "\\_SB.GPO2", 0x00, ResourceConsumer, , ) - { // Pin list - 0 - } - }) - Return (RBUF) - } - } - } -} - -which can then be compiled to AML binary format: - -$ iasl minnowmax.asl - -Intel ACPI Component Architecture -ASL Optimizing Compiler version 20140214-64 [Mar 29 2014] -Copyright (c) 2000 - 2014 Intel Corporation - -ASL Input: minnomax.asl - 30 lines, 614 bytes, 7 keywords -AML Output: minnowmax.aml - 165 bytes, 6 named objects, 1 executable opcodes - -[1] http://wiki.minnowboard.org/MinnowBoard_MAX#Low_Speed_Expansion_Connector_.28Top.29 - -The resulting AML code can then be loaded by the kernel using one of the methods -below. - -== Loading ACPI SSDTs from initrd == - -This option allows loading of user defined SSDTs from initrd and it is useful -when the system does not support EFI or when there is not enough EFI storage. - -It works in a similar way with initrd based ACPI tables override/upgrade: SSDT -aml code must be placed in the first, uncompressed, initrd under the -"kernel/firmware/acpi" path. Multiple files can be used and this will translate -in loading multiple tables. Only SSDT and OEM tables are allowed. See -initrd_table_override.txt for more details. - -Here is an example: - -# Add the raw ACPI tables to an uncompressed cpio archive. -# They must be put into a /kernel/firmware/acpi directory inside the -# cpio archive. -# The uncompressed cpio archive must be the first. -# Other, typically compressed cpio archives, must be -# concatenated on top of the uncompressed one. -mkdir -p kernel/firmware/acpi -cp ssdt.aml kernel/firmware/acpi - -# Create the uncompressed cpio archive and concatenate the original initrd -# on top: -find kernel | cpio -H newc --create > /boot/instrumented_initrd -cat /boot/initrd >>/boot/instrumented_initrd - -== Loading ACPI SSDTs from EFI variables == - -This is the preferred method, when EFI is supported on the platform, because it -allows a persistent, OS independent way of storing the user defined SSDTs. There -is also work underway to implement EFI support for loading user defined SSDTs -and using this method will make it easier to convert to the EFI loading -mechanism when that will arrive. - -In order to load SSDTs from an EFI variable the efivar_ssdt kernel command line -parameter can be used. The argument for the option is the variable name to -use. If there are multiple variables with the same name but with different -vendor GUIDs, all of them will be loaded. - -In order to store the AML code in an EFI variable the efivarfs filesystem can be -used. It is enabled and mounted by default in /sys/firmware/efi/efivars in all -recent distribution. - -Creating a new file in /sys/firmware/efi/efivars will automatically create a new -EFI variable. Updating a file in /sys/firmware/efi/efivars will update the EFI -variable. Please note that the file name needs to be specially formatted as -"Name-GUID" and that the first 4 bytes in the file (little-endian format) -represent the attributes of the EFI variable (see EFI_VARIABLE_MASK in -include/linux/efi.h). Writing to the file must also be done with one write -operation. - -For example, you can use the following bash script to create/update an EFI -variable with the content from a given file: - -#!/bin/sh -e - -while ! [ -z "$1" ]; do - case "$1" in - "-f") filename="$2"; shift;; - "-g") guid="$2"; shift;; - *) name="$1";; - esac - shift -done - -usage() -{ - echo "Syntax: ${0##*/} -f filename [ -g guid ] name" - exit 1 -} - -[ -n "$name" -a -f "$filename" ] || usage - -EFIVARFS="/sys/firmware/efi/efivars" - -[ -d "$EFIVARFS" ] || exit 2 - -if stat -tf $EFIVARFS | grep -q -v de5e81e4; then - mount -t efivarfs none $EFIVARFS -fi - -# try to pick up an existing GUID -[ -n "$guid" ] || guid=$(find "$EFIVARFS" -name "$name-*" | head -n1 | cut -f2- -d-) - -# use a randomly generated GUID -[ -n "$guid" ] || guid="$(cat /proc/sys/kernel/random/uuid)" - -# efivarfs expects all of the data in one write -tmp=$(mktemp) -/bin/echo -ne "\007\000\000\000" | cat - $filename > $tmp -dd if=$tmp of="$EFIVARFS/$name-$guid" bs=$(stat -c %s $tmp) -rm $tmp - -== Loading ACPI SSDTs from configfs == - -This option allows loading of user defined SSDTs from userspace via the configfs -interface. The CONFIG_ACPI_CONFIGFS option must be select and configfs must be -mounted. In the following examples, we assume that configfs has been mounted in -/config. - -New tables can be loading by creating new directories in /config/acpi/table/ and -writing the SSDT aml code in the aml attribute: - -cd /config/acpi/table -mkdir my_ssdt -cat ~/ssdt.aml > my_ssdt/aml diff --git a/Documentation/acpi/cppc_sysfs.txt b/Documentation/admin-guide/acpi/cppc_sysfs.rst index f20fb445135d..a4b99afbe331 100644 --- a/Documentation/acpi/cppc_sysfs.txt +++ b/Documentation/admin-guide/acpi/cppc_sysfs.rst @@ -1,5 +1,11 @@ +.. SPDX-License-Identifier: GPL-2.0 - Collaborative Processor Performance Control (CPPC) +================================================== +Collaborative Processor Performance Control (CPPC) +================================================== + +CPPC +==== CPPC defined in the ACPI spec describes a mechanism for the OS to manage the performance of a logical processor on a contigious and abstract performance @@ -10,31 +16,28 @@ For more details on CPPC please refer to the ACPI specification at: http://uefi.org/specifications -Some of the CPPC registers are exposed via sysfs under: - -/sys/devices/system/cpu/cpuX/acpi_cppc/ - -for each cpu X +Some of the CPPC registers are exposed via sysfs under:: --------------------------------------------------------------------------------- + /sys/devices/system/cpu/cpuX/acpi_cppc/ -$ ls -lR /sys/devices/system/cpu/cpu0/acpi_cppc/ -/sys/devices/system/cpu/cpu0/acpi_cppc/: -total 0 --r--r--r-- 1 root root 65536 Mar 5 19:38 feedback_ctrs --r--r--r-- 1 root root 65536 Mar 5 19:38 highest_perf --r--r--r-- 1 root root 65536 Mar 5 19:38 lowest_freq --r--r--r-- 1 root root 65536 Mar 5 19:38 lowest_nonlinear_perf --r--r--r-- 1 root root 65536 Mar 5 19:38 lowest_perf --r--r--r-- 1 root root 65536 Mar 5 19:38 nominal_freq --r--r--r-- 1 root root 65536 Mar 5 19:38 nominal_perf --r--r--r-- 1 root root 65536 Mar 5 19:38 reference_perf --r--r--r-- 1 root root 65536 Mar 5 19:38 wraparound_time +for each cpu X:: --------------------------------------------------------------------------------- + $ ls -lR /sys/devices/system/cpu/cpu0/acpi_cppc/ + /sys/devices/system/cpu/cpu0/acpi_cppc/: + total 0 + -r--r--r-- 1 root root 65536 Mar 5 19:38 feedback_ctrs + -r--r--r-- 1 root root 65536 Mar 5 19:38 highest_perf + -r--r--r-- 1 root root 65536 Mar 5 19:38 lowest_freq + -r--r--r-- 1 root root 65536 Mar 5 19:38 lowest_nonlinear_perf + -r--r--r-- 1 root root 65536 Mar 5 19:38 lowest_perf + -r--r--r-- 1 root root 65536 Mar 5 19:38 nominal_freq + -r--r--r-- 1 root root 65536 Mar 5 19:38 nominal_perf + -r--r--r-- 1 root root 65536 Mar 5 19:38 reference_perf + -r--r--r-- 1 root root 65536 Mar 5 19:38 wraparound_time * highest_perf : Highest performance of this processor (abstract scale). -* nominal_perf : Highest sustained performance of this processor (abstract scale). +* nominal_perf : Highest sustained performance of this processor + (abstract scale). * lowest_nonlinear_perf : Lowest performance of this processor with nonlinear power savings (abstract scale). * lowest_perf : Lowest performance of this processor (abstract scale). @@ -48,22 +51,26 @@ total 0 * feedback_ctrs : Includes both Reference and delivered performance counter. Reference counter ticks up proportional to processor's reference performance. Delivered counter ticks up proportional to processor's delivered performance. -* wraparound_time: Minimum time for the feedback counters to wraparound (seconds). +* wraparound_time: Minimum time for the feedback counters to wraparound + (seconds). * reference_perf : Performance level at which reference performance counter accumulates (abstract scale). --------------------------------------------------------------------------------- - Computing Average Delivered Performance +Computing Average Delivered Performance +======================================= + +Below describes the steps to compute the average performance delivered by +taking two different snapshots of feedback counters at time T1 and T2. + + T1: Read feedback_ctrs as fbc_t1 + Wait or run some workload -Below describes the steps to compute the average performance delivered by taking -two different snapshots of feedback counters at time T1 and T2. + T2: Read feedback_ctrs as fbc_t2 -T1: Read feedback_ctrs as fbc_t1 - Wait or run some workload -T2: Read feedback_ctrs as fbc_t2 +:: -delivered_counter_delta = fbc_t2[del] - fbc_t1[del] -reference_counter_delta = fbc_t2[ref] - fbc_t1[ref] + delivered_counter_delta = fbc_t2[del] - fbc_t1[del] + reference_counter_delta = fbc_t2[ref] - fbc_t1[ref] -delivered_perf = (refernce_perf x delivered_counter_delta) / reference_counter_delta + delivered_perf = (refernce_perf x delivered_counter_delta) / reference_counter_delta diff --git a/Documentation/acpi/dsdt-override.txt b/Documentation/admin-guide/acpi/dsdt-override.rst index 784841caa6e6..50bd7f194bf4 100644 --- a/Documentation/acpi/dsdt-override.txt +++ b/Documentation/admin-guide/acpi/dsdt-override.rst @@ -1,6 +1,12 @@ +.. SPDX-License-Identifier: GPL-2.0 + +=============== +Overriding DSDT +=============== + Linux supports a method of overriding the BIOS DSDT: -CONFIG_ACPI_CUSTOM_DSDT builds the image into the kernel. +CONFIG_ACPI_CUSTOM_DSDT - builds the image into the kernel. When to use this method is described in detail on the Linux/ACPI home page: diff --git a/Documentation/admin-guide/acpi/index.rst b/Documentation/admin-guide/acpi/index.rst new file mode 100644 index 000000000000..4d13eeea1eca --- /dev/null +++ b/Documentation/admin-guide/acpi/index.rst @@ -0,0 +1,14 @@ +============ +ACPI Support +============ + +Here we document in detail how to interact with various mechanisms in +the Linux ACPI support. + +.. toctree:: + :maxdepth: 1 + + initrd_table_override + dsdt-override + ssdt-overlays + cppc_sysfs diff --git a/Documentation/admin-guide/acpi/initrd_table_override.rst b/Documentation/admin-guide/acpi/initrd_table_override.rst new file mode 100644 index 000000000000..cbd768207631 --- /dev/null +++ b/Documentation/admin-guide/acpi/initrd_table_override.rst @@ -0,0 +1,115 @@ +.. SPDX-License-Identifier: GPL-2.0 + +================================ +Upgrading ACPI tables via initrd +================================ + +What is this about +================== + +If the ACPI_TABLE_UPGRADE compile option is true, it is possible to +upgrade the ACPI execution environment that is defined by the ACPI tables +via upgrading the ACPI tables provided by the BIOS with an instrumented, +modified, more recent version one, or installing brand new ACPI tables. + +When building initrd with kernel in a single image, option +ACPI_TABLE_OVERRIDE_VIA_BUILTIN_INITRD should also be true for this +feature to work. + +For a full list of ACPI tables that can be upgraded/installed, take a look +at the char `*table_sigs[MAX_ACPI_SIGNATURE];` definition in +drivers/acpi/tables.c. + +All ACPI tables iasl (Intel's ACPI compiler and disassembler) knows should +be overridable, except: + + - ACPI_SIG_RSDP (has a signature of 6 bytes) + - ACPI_SIG_FACS (does not have an ordinary ACPI table header) + +Both could get implemented as well. + + +What is this for +================ + +Complain to your platform/BIOS vendor if you find a bug which is so severe +that a workaround is not accepted in the Linux kernel. And this facility +allows you to upgrade the buggy tables before your platform/BIOS vendor +releases an upgraded BIOS binary. + +This facility can be used by platform/BIOS vendors to provide a Linux +compatible environment without modifying the underlying platform firmware. + +This facility also provides a powerful feature to easily debug and test +ACPI BIOS table compatibility with the Linux kernel by modifying old +platform provided ACPI tables or inserting new ACPI tables. + +It can and should be enabled in any kernel because there is no functional +change with not instrumented initrds. + + +How does it work +================ +:: + + # Extract the machine's ACPI tables: + cd /tmp + acpidump >acpidump + acpixtract -a acpidump + # Disassemble, modify and recompile them: + iasl -d *.dat + # For example add this statement into a _PRT (PCI Routing Table) function + # of the DSDT: + Store("HELLO WORLD", debug) + # And increase the OEM Revision. For example, before modification: + DefinitionBlock ("DSDT.aml", "DSDT", 2, "INTEL ", "TEMPLATE", 0x00000000) + # After modification: + DefinitionBlock ("DSDT.aml", "DSDT", 2, "INTEL ", "TEMPLATE", 0x00000001) + iasl -sa dsdt.dsl + # Add the raw ACPI tables to an uncompressed cpio archive. + # They must be put into a /kernel/firmware/acpi directory inside the cpio + # archive. Note that if the table put here matches a platform table + # (similar Table Signature, and similar OEMID, and similar OEM Table ID) + # with a more recent OEM Revision, the platform table will be upgraded by + # this table. If the table put here doesn't match a platform table + # (dissimilar Table Signature, or dissimilar OEMID, or dissimilar OEM Table + # ID), this table will be appended. + mkdir -p kernel/firmware/acpi + cp dsdt.aml kernel/firmware/acpi + # A maximum of "NR_ACPI_INITRD_TABLES (64)" tables are currently allowed + # (see osl.c): + iasl -sa facp.dsl + iasl -sa ssdt1.dsl + cp facp.aml kernel/firmware/acpi + cp ssdt1.aml kernel/firmware/acpi + # The uncompressed cpio archive must be the first. Other, typically + # compressed cpio archives, must be concatenated on top of the uncompressed + # one. Following command creates the uncompressed cpio archive and + # concatenates the original initrd on top: + find kernel | cpio -H newc --create > /boot/instrumented_initrd + cat /boot/initrd >>/boot/instrumented_initrd + # reboot with increased acpi debug level, e.g. boot params: + acpi.debug_level=0x2 acpi.debug_layer=0xFFFFFFFF + # and check your syslog: + [ 1.268089] ACPI: PCI Interrupt Routing Table [\_SB_.PCI0._PRT] + [ 1.272091] [ACPI Debug] String [0x0B] "HELLO WORLD" + +iasl is able to disassemble and recompile quite a lot different, +also static ACPI tables. + + +Where to retrieve userspace tools +================================= + +iasl and acpixtract are part of Intel's ACPICA project: +http://acpica.org/ + +and should be packaged by distributions (for example in the acpica package +on SUSE). + +acpidump can be found in Len Browns pmtools: +ftp://kernel.org/pub/linux/kernel/people/lenb/acpi/utils/pmtools/acpidump + +This tool is also part of the acpica package on SUSE. +Alternatively, used ACPI tables can be retrieved via sysfs in latest kernels: +/sys/firmware/acpi/tables diff --git a/Documentation/admin-guide/acpi/ssdt-overlays.rst b/Documentation/admin-guide/acpi/ssdt-overlays.rst new file mode 100644 index 000000000000..da37455f96c9 --- /dev/null +++ b/Documentation/admin-guide/acpi/ssdt-overlays.rst @@ -0,0 +1,180 @@ +.. SPDX-License-Identifier: GPL-2.0 + +============= +SSDT Overlays +============= + +In order to support ACPI open-ended hardware configurations (e.g. development +boards) we need a way to augment the ACPI configuration provided by the firmware +image. A common example is connecting sensors on I2C / SPI buses on development +boards. + +Although this can be accomplished by creating a kernel platform driver or +recompiling the firmware image with updated ACPI tables, neither is practical: +the former proliferates board specific kernel code while the latter requires +access to firmware tools which are often not publicly available. + +Because ACPI supports external references in AML code a more practical +way to augment firmware ACPI configuration is by dynamically loading +user defined SSDT tables that contain the board specific information. + +For example, to enumerate a Bosch BMA222E accelerometer on the I2C bus of the +Minnowboard MAX development board exposed via the LSE connector [1], the +following ASL code can be used:: + + DefinitionBlock ("minnowmax.aml", "SSDT", 1, "Vendor", "Accel", 0x00000003) + { + External (\_SB.I2C6, DeviceObj) + + Scope (\_SB.I2C6) + { + Device (STAC) + { + Name (_ADR, Zero) + Name (_HID, "BMA222E") + + Method (_CRS, 0, Serialized) + { + Name (RBUF, ResourceTemplate () + { + I2cSerialBus (0x0018, ControllerInitiated, 0x00061A80, + AddressingMode7Bit, "\\_SB.I2C6", 0x00, + ResourceConsumer, ,) + GpioInt (Edge, ActiveHigh, Exclusive, PullDown, 0x0000, + "\\_SB.GPO2", 0x00, ResourceConsumer, , ) + { // Pin list + 0 + } + }) + Return (RBUF) + } + } + } + } + +which can then be compiled to AML binary format:: + + $ iasl minnowmax.asl + + Intel ACPI Component Architecture + ASL Optimizing Compiler version 20140214-64 [Mar 29 2014] + Copyright (c) 2000 - 2014 Intel Corporation + + ASL Input: minnomax.asl - 30 lines, 614 bytes, 7 keywords + AML Output: minnowmax.aml - 165 bytes, 6 named objects, 1 executable opcodes + +[1] http://wiki.minnowboard.org/MinnowBoard_MAX#Low_Speed_Expansion_Connector_.28Top.29 + +The resulting AML code can then be loaded by the kernel using one of the methods +below. + +Loading ACPI SSDTs from initrd +============================== + +This option allows loading of user defined SSDTs from initrd and it is useful +when the system does not support EFI or when there is not enough EFI storage. + +It works in a similar way with initrd based ACPI tables override/upgrade: SSDT +aml code must be placed in the first, uncompressed, initrd under the +"kernel/firmware/acpi" path. Multiple files can be used and this will translate +in loading multiple tables. Only SSDT and OEM tables are allowed. See +initrd_table_override.txt for more details. + +Here is an example:: + + # Add the raw ACPI tables to an uncompressed cpio archive. + # They must be put into a /kernel/firmware/acpi directory inside the + # cpio archive. + # The uncompressed cpio archive must be the first. + # Other, typically compressed cpio archives, must be + # concatenated on top of the uncompressed one. + mkdir -p kernel/firmware/acpi + cp ssdt.aml kernel/firmware/acpi + + # Create the uncompressed cpio archive and concatenate the original initrd + # on top: + find kernel | cpio -H newc --create > /boot/instrumented_initrd + cat /boot/initrd >>/boot/instrumented_initrd + +Loading ACPI SSDTs from EFI variables +===================================== + +This is the preferred method, when EFI is supported on the platform, because it +allows a persistent, OS independent way of storing the user defined SSDTs. There +is also work underway to implement EFI support for loading user defined SSDTs +and using this method will make it easier to convert to the EFI loading +mechanism when that will arrive. + +In order to load SSDTs from an EFI variable the efivar_ssdt kernel command line +parameter can be used. The argument for the option is the variable name to +use. If there are multiple variables with the same name but with different +vendor GUIDs, all of them will be loaded. + +In order to store the AML code in an EFI variable the efivarfs filesystem can be +used. It is enabled and mounted by default in /sys/firmware/efi/efivars in all +recent distribution. + +Creating a new file in /sys/firmware/efi/efivars will automatically create a new +EFI variable. Updating a file in /sys/firmware/efi/efivars will update the EFI +variable. Please note that the file name needs to be specially formatted as +"Name-GUID" and that the first 4 bytes in the file (little-endian format) +represent the attributes of the EFI variable (see EFI_VARIABLE_MASK in +include/linux/efi.h). Writing to the file must also be done with one write +operation. + +For example, you can use the following bash script to create/update an EFI +variable with the content from a given file:: + + #!/bin/sh -e + + while ! [ -z "$1" ]; do + case "$1" in + "-f") filename="$2"; shift;; + "-g") guid="$2"; shift;; + *) name="$1";; + esac + shift + done + + usage() + { + echo "Syntax: ${0##*/} -f filename [ -g guid ] name" + exit 1 + } + + [ -n "$name" -a -f "$filename" ] || usage + + EFIVARFS="/sys/firmware/efi/efivars" + + [ -d "$EFIVARFS" ] || exit 2 + + if stat -tf $EFIVARFS | grep -q -v de5e81e4; then + mount -t efivarfs none $EFIVARFS + fi + + # try to pick up an existing GUID + [ -n "$guid" ] || guid=$(find "$EFIVARFS" -name "$name-*" | head -n1 | cut -f2- -d-) + + # use a randomly generated GUID + [ -n "$guid" ] || guid="$(cat /proc/sys/kernel/random/uuid)" + + # efivarfs expects all of the data in one write + tmp=$(mktemp) + /bin/echo -ne "\007\000\000\000" | cat - $filename > $tmp + dd if=$tmp of="$EFIVARFS/$name-$guid" bs=$(stat -c %s $tmp) + rm $tmp + +Loading ACPI SSDTs from configfs +================================ + +This option allows loading of user defined SSDTs from userspace via the configfs +interface. The CONFIG_ACPI_CONFIGFS option must be select and configfs must be +mounted. In the following examples, we assume that configfs has been mounted in +/config. + +New tables can be loading by creating new directories in /config/acpi/table/ and +writing the SSDT aml code in the aml attribute:: + + cd /config/acpi/table + mkdir my_ssdt + cat ~/ssdt.aml > my_ssdt/aml diff --git a/Documentation/admin-guide/index.rst b/Documentation/admin-guide/index.rst index 0a491676685e..5b8286fdd91b 100644 --- a/Documentation/admin-guide/index.rst +++ b/Documentation/admin-guide/index.rst @@ -77,6 +77,7 @@ configure specific aspects of kernel behavior to your liking. LSM/index mm/index perf-security + acpi/index .. only:: subproject and html diff --git a/Documentation/admin-guide/kernel-parameters.rst b/Documentation/admin-guide/kernel-parameters.rst index b8d0bc07ed0a..0124980dca2d 100644 --- a/Documentation/admin-guide/kernel-parameters.rst +++ b/Documentation/admin-guide/kernel-parameters.rst @@ -88,6 +88,7 @@ parameter is applicable:: APIC APIC support is enabled. APM Advanced Power Management support is enabled. ARM ARM architecture is enabled. + ARM64 ARM64 architecture is enabled. AX25 Appropriate AX.25 support is enabled. CLK Common clock infrastructure is enabled. CMA Contiguous Memory Area support is enabled. diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index 2b8ee90bb644..fd03e2b629bb 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -704,8 +704,11 @@ upon panic. This parameter reserves the physical memory region [offset, offset + size] for that kernel image. If '@offset' is omitted, then a suitable offset - is selected automatically. Check - Documentation/kdump/kdump.txt for further details. + is selected automatically. + [KNL, x86_64] select a region under 4G first, and + fall back to reserve region above 4G when '@offset' + hasn't been specified. + See Documentation/kdump/kdump.txt for further details. crashkernel=range1:size1[,range2:size2,...][@offset] [KNL] Same as above, but depends on the memory @@ -2544,6 +2547,40 @@ in the "bleeding edge" mini2440 support kernel at http://repo.or.cz/w/linux-2.6/mini2440.git + mitigations= + [X86,PPC,S390,ARM64] Control optional mitigations for + CPU vulnerabilities. This is a set of curated, + arch-independent options, each of which is an + aggregation of existing arch-specific options. + + off + Disable all optional CPU mitigations. This + improves system performance, but it may also + expose users to several CPU vulnerabilities. + Equivalent to: nopti [X86,PPC] + kpti=0 [ARM64] + nospectre_v1 [PPC] + nobp=0 [S390] + nospectre_v2 [X86,PPC,S390,ARM64] + spectre_v2_user=off [X86] + spec_store_bypass_disable=off [X86,PPC] + ssbd=force-off [ARM64] + l1tf=off [X86] + + auto (default) + Mitigate all CPU vulnerabilities, but leave SMT + enabled, even if it's vulnerable. This is for + users who don't want to be surprised by SMT + getting disabled across kernel upgrades, or who + have other ways of avoiding SMT-based attacks. + Equivalent to: (default behavior) + + auto,nosmt + Mitigate all CPU vulnerabilities, disabling SMT + if needed. This is for users who always want to + be fully mitigated, even if it means losing SMT. + Equivalent to: l1tf=flush,nosmt [X86] + mminit_loglevel= [KNL] When CONFIG_DEBUG_MEMORY_INIT is set, this parameter allows control of the logging verbosity for @@ -2873,10 +2910,10 @@ check bypass). With this option data leaks are possible in the system. - nospectre_v2 [X86,PPC_FSL_BOOK3E] Disable all mitigations for the Spectre variant 2 - (indirect branch prediction) vulnerability. System may - allow data leaks with this option, which is equivalent - to spectre_v2=off. + nospectre_v2 [X86,PPC_FSL_BOOK3E,ARM64] Disable all mitigations for + the Spectre variant 2 (indirect branch prediction) + vulnerability. System may allow data leaks with this + option. nospec_store_bypass_disable [HW] Disable all mitigations for the Speculative Store Bypass vulnerability @@ -3394,6 +3431,8 @@ bridges without forcing it upstream. Note: this removes isolation between devices and may put more devices in an IOMMU group. + force_floating [S390] Force usage of floating interrupts. + nomio [S390] Do not use MIO instructions. pcie_aspm= [PCIE] Forcibly enable or disable PCIe Active State Power Management. @@ -3623,7 +3662,9 @@ see CONFIG_RAS_CEC help text. rcu_nocbs= [KNL] - The argument is a cpu list, as described above. + The argument is a cpu list, as described above, + except that the string "all" can be used to + specify every CPU on the system. In kernels built with CONFIG_RCU_NOCB_CPU=y, set the specified list of CPUs to be no-callback CPUs. @@ -4703,6 +4744,10 @@ [x86] unstable: mark the TSC clocksource as unstable, this marks the TSC unconditionally unstable at bootup and avoids any further wobbles once the TSC watchdog notices. + [x86] nowatchdog: disable clocksource watchdog. Used + in situations with strict latency requirements (where + interruptions from clocksource watchdog are not + acceptable). turbografx.map[2|3]= [HW,JOY] TurboGraFX parallel port interface diff --git a/Documentation/admin-guide/pm/cpufreq.rst b/Documentation/admin-guide/pm/cpufreq.rst index 7eca9026a9ed..0c74a7784964 100644 --- a/Documentation/admin-guide/pm/cpufreq.rst +++ b/Documentation/admin-guide/pm/cpufreq.rst @@ -1,3 +1,6 @@ +.. SPDX-License-Identifier: GPL-2.0 +.. include:: <isonum.txt> + .. |struct cpufreq_policy| replace:: :c:type:`struct cpufreq_policy <cpufreq_policy>` .. |intel_pstate| replace:: :doc:`intel_pstate <intel_pstate>` @@ -5,9 +8,10 @@ CPU Performance Scaling ======================= -:: +:Copyright: |copy| 2017 Intel Corporation + +:Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com> - Copyright (c) 2017 Intel Corp., Rafael J. Wysocki <rafael.j.wysocki@intel.com> The Concept of CPU Performance Scaling ====================================== @@ -396,8 +400,8 @@ RT or deadline scheduling classes, the governor will increase the frequency to the allowed maximum (that is, the ``scaling_max_freq`` policy limit). In turn, if it is invoked by the CFS scheduling class, the governor will use the Per-Entity Load Tracking (PELT) metric for the root control group of the -given CPU as the CPU utilization estimate (see the `Per-entity load tracking`_ -LWN.net article for a description of the PELT mechanism). Then, the new +given CPU as the CPU utilization estimate (see the *Per-entity load tracking* +LWN.net article [1]_ for a description of the PELT mechanism). Then, the new CPU frequency to apply is computed in accordance with the formula f = 1.25 * ``f_0`` * ``util`` / ``max`` @@ -698,4 +702,8 @@ hardware feature (e.g. all Intel ones), even if the :c:macro:`CONFIG_X86_ACPI_CPUFREQ_CPB` configuration option is set. -.. _Per-entity load tracking: https://lwn.net/Articles/531853/ +References +========== + +.. [1] Jonathan Corbet, *Per-entity load tracking*, + https://lwn.net/Articles/531853/ diff --git a/Documentation/admin-guide/pm/cpuidle.rst b/Documentation/admin-guide/pm/cpuidle.rst index 9c58b35a81cb..e70b365dbc60 100644 --- a/Documentation/admin-guide/pm/cpuidle.rst +++ b/Documentation/admin-guide/pm/cpuidle.rst @@ -1,3 +1,6 @@ +.. SPDX-License-Identifier: GPL-2.0 +.. include:: <isonum.txt> + .. |struct cpuidle_state| replace:: :c:type:`struct cpuidle_state <cpuidle_state>` .. |cpufreq| replace:: :doc:`CPU Performance Scaling <cpufreq>` @@ -5,9 +8,10 @@ CPU Idle Time Management ======================== -:: +:Copyright: |copy| 2018 Intel Corporation + +:Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com> - Copyright (c) 2018 Intel Corp., Rafael J. Wysocki <rafael.j.wysocki@intel.com> Concepts ======== diff --git a/Documentation/admin-guide/pm/index.rst b/Documentation/admin-guide/pm/index.rst index 49237ac73442..39f8f9f81e7a 100644 --- a/Documentation/admin-guide/pm/index.rst +++ b/Documentation/admin-guide/pm/index.rst @@ -1,3 +1,5 @@ +.. SPDX-License-Identifier: GPL-2.0 + ================ Power Management ================ diff --git a/Documentation/admin-guide/pm/intel_epb.rst b/Documentation/admin-guide/pm/intel_epb.rst new file mode 100644 index 000000000000..005121167af7 --- /dev/null +++ b/Documentation/admin-guide/pm/intel_epb.rst @@ -0,0 +1,41 @@ +.. SPDX-License-Identifier: GPL-2.0 +.. include:: <isonum.txt> + +====================================== +Intel Performance and Energy Bias Hint +====================================== + +:Copyright: |copy| 2019 Intel Corporation + +:Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com> + + +.. kernel-doc:: arch/x86/kernel/cpu/intel_epb.c + :doc: overview + +Intel Performance and Energy Bias Attribute in ``sysfs`` +======================================================== + +The Intel Performance and Energy Bias Hint (EPB) value for a given (logical) CPU +can be checked or updated through a ``sysfs`` attribute (file) under +:file:`/sys/devices/system/cpu/cpu<N>/power/`, where the CPU number ``<N>`` +is allocated at the system initialization time: + +``energy_perf_bias`` + Shows the current EPB value for the CPU in a sliding scale 0 - 15, where + a value of 0 corresponds to a hint preference for highest performance + and a value of 15 corresponds to the maximum energy savings. + + In order to update the EPB value for the CPU, this attribute can be + written to, either with a number in the 0 - 15 sliding scale above, or + with one of the strings: "performance", "balance-performance", "normal", + "balance-power", "power" that represent values reflected by their + meaning. + + This attribute is present for all online CPUs supporting the EPB + feature. + +Note that while the EPB interface to the processor is defined at the logical CPU +level, the physical register backing it may be shared by multiple CPUs (for +example, SMT siblings or cores in one package). For this reason, updating the +EPB value for one CPU may cause the EPB values for other CPUs to change. diff --git a/Documentation/admin-guide/pm/intel_pstate.rst b/Documentation/admin-guide/pm/intel_pstate.rst index ec0f7c111f65..67e414e34f37 100644 --- a/Documentation/admin-guide/pm/intel_pstate.rst +++ b/Documentation/admin-guide/pm/intel_pstate.rst @@ -1,10 +1,13 @@ +.. SPDX-License-Identifier: GPL-2.0 +.. include:: <isonum.txt> + =============================================== ``intel_pstate`` CPU Performance Scaling Driver =============================================== -:: +:Copyright: |copy| 2017 Intel Corporation - Copyright (c) 2017 Intel Corp., Rafael J. Wysocki <rafael.j.wysocki@intel.com> +:Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com> General Information @@ -20,11 +23,10 @@ you have not done that yet.] For the processors supported by ``intel_pstate``, the P-state concept is broader than just an operating frequency or an operating performance point (see the -`LinuxCon Europe 2015 presentation by Kristen Accardi <LCEU2015_>`_ for more +LinuxCon Europe 2015 presentation by Kristen Accardi [1]_ for more information about that). For this reason, the representation of P-states used by ``intel_pstate`` internally follows the hardware specification (for details -refer to `Intel® 64 and IA-32 Architectures Software Developer’s Manual -Volume 3: System Programming Guide <SDM_>`_). However, the ``CPUFreq`` core +refer to Intel Software Developer’s Manual [2]_). However, the ``CPUFreq`` core uses frequencies for identifying operating performance points of CPUs and frequencies are involved in the user space interface exposed by it, so ``intel_pstate`` maps its internal representation of P-states to frequencies too @@ -561,9 +563,9 @@ or to pin every task potentially sensitive to them to a specific CPU.] On the majority of systems supported by ``intel_pstate``, the ACPI tables provided by the platform firmware contain ``_PSS`` objects returning information -that can be used for CPU performance scaling (refer to the `ACPI specification`_ -for details on the ``_PSS`` objects and the format of the information returned -by them). +that can be used for CPU performance scaling (refer to the ACPI specification +[3]_ for details on the ``_PSS`` objects and the format of the information +returned by them). The information returned by the ACPI ``_PSS`` objects is used by the ``acpi-cpufreq`` scaling driver. On systems supported by ``intel_pstate`` @@ -728,6 +730,14 @@ P-state is called, the ``ftrace`` filter can be set to to <idle>-0 [000] ..s. 2537.654843: intel_pstate_set_pstate <-intel_pstate_timer_func -.. _LCEU2015: http://events.linuxfoundation.org/sites/events/files/slides/LinuxConEurope_2015.pdf -.. _SDM: http://www.intel.com/content/www/us/en/architecture-and-technology/64-ia-32-architectures-software-developer-system-programming-manual-325384.html -.. _ACPI specification: http://www.uefi.org/sites/default/files/resources/ACPI_6_1.pdf +References +========== + +.. [1] Kristen Accardi, *Balancing Power and Performance in the Linux Kernel*, + http://events.linuxfoundation.org/sites/events/files/slides/LinuxConEurope_2015.pdf + +.. [2] *Intel® 64 and IA-32 Architectures Software Developer’s Manual Volume 3: System Programming Guide*, + http://www.intel.com/content/www/us/en/architecture-and-technology/64-ia-32-architectures-software-developer-system-programming-manual-325384.html + +.. [3] *Advanced Configuration and Power Interface Specification*, + https://uefi.org/sites/default/files/resources/ACPI_6_3_final_Jan30.pdf diff --git a/Documentation/admin-guide/pm/sleep-states.rst b/Documentation/admin-guide/pm/sleep-states.rst index dbf5acd49f35..cd3a28cb81f4 100644 --- a/Documentation/admin-guide/pm/sleep-states.rst +++ b/Documentation/admin-guide/pm/sleep-states.rst @@ -1,10 +1,14 @@ +.. SPDX-License-Identifier: GPL-2.0 +.. include:: <isonum.txt> + =================== System Sleep States =================== -:: +:Copyright: |copy| 2017 Intel Corporation + +:Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com> - Copyright (c) 2017 Intel Corp., Rafael J. Wysocki <rafael.j.wysocki@intel.com> Sleep states are global low-power states of the entire system in which user space code cannot be executed and the overall system activity is significantly diff --git a/Documentation/admin-guide/pm/strategies.rst b/Documentation/admin-guide/pm/strategies.rst index afe4d3f831fe..dd0362e32fa5 100644 --- a/Documentation/admin-guide/pm/strategies.rst +++ b/Documentation/admin-guide/pm/strategies.rst @@ -1,10 +1,14 @@ +.. SPDX-License-Identifier: GPL-2.0 +.. include:: <isonum.txt> + =========================== Power Management Strategies =========================== -:: +:Copyright: |copy| 2017 Intel Corporation + +:Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com> - Copyright (c) 2017 Intel Corp., Rafael J. Wysocki <rafael.j.wysocki@intel.com> The Linux kernel supports two major high-level power management strategies. diff --git a/Documentation/admin-guide/pm/system-wide.rst b/Documentation/admin-guide/pm/system-wide.rst index 0c81e4c5de39..2b1f987b34f0 100644 --- a/Documentation/admin-guide/pm/system-wide.rst +++ b/Documentation/admin-guide/pm/system-wide.rst @@ -1,3 +1,5 @@ +.. SPDX-License-Identifier: GPL-2.0 + ============================ System-Wide Power Management ============================ diff --git a/Documentation/admin-guide/pm/working-state.rst b/Documentation/admin-guide/pm/working-state.rst index b6cef9b5e961..fc298eb1234b 100644 --- a/Documentation/admin-guide/pm/working-state.rst +++ b/Documentation/admin-guide/pm/working-state.rst @@ -1,3 +1,5 @@ +.. SPDX-License-Identifier: GPL-2.0 + ============================== Working-State Power Management ============================== @@ -8,3 +10,4 @@ Working-State Power Management cpuidle cpufreq intel_pstate + intel_epb diff --git a/Documentation/arm64/cpu-feature-registers.txt b/Documentation/arm64/cpu-feature-registers.txt index d4b4dd1fe786..684a0da39378 100644 --- a/Documentation/arm64/cpu-feature-registers.txt +++ b/Documentation/arm64/cpu-feature-registers.txt @@ -209,6 +209,22 @@ infrastructure: | AT | [35-32] | y | x--------------------------------------------------x + 6) ID_AA64ZFR0_EL1 - SVE feature ID register 0 + + x--------------------------------------------------x + | Name | bits | visible | + |--------------------------------------------------| + | SM4 | [43-40] | y | + |--------------------------------------------------| + | SHA3 | [35-32] | y | + |--------------------------------------------------| + | BitPerm | [19-16] | y | + |--------------------------------------------------| + | AES | [7-4] | y | + |--------------------------------------------------| + | SVEVer | [3-0] | y | + x--------------------------------------------------x + Appendix I: Example --------------------------- diff --git a/Documentation/arm64/elf_hwcaps.txt b/Documentation/arm64/elf_hwcaps.txt index 13d6691b37be..b73a2519ecf2 100644 --- a/Documentation/arm64/elf_hwcaps.txt +++ b/Documentation/arm64/elf_hwcaps.txt @@ -13,9 +13,9 @@ architected discovery mechanism available to userspace code at EL0. The kernel exposes the presence of these features to userspace through a set of flags called hwcaps, exposed in the auxilliary vector. -Userspace software can test for features by acquiring the AT_HWCAP entry -of the auxilliary vector, and testing whether the relevant flags are -set, e.g. +Userspace software can test for features by acquiring the AT_HWCAP or +AT_HWCAP2 entry of the auxiliary vector, and testing whether the relevant +flags are set, e.g. bool floating_point_is_present(void) { @@ -135,6 +135,10 @@ HWCAP_DCPOP Functionality implied by ID_AA64ISAR1_EL1.DPB == 0b0001. +HWCAP2_DCPODP + + Functionality implied by ID_AA64ISAR1_EL1.DPB == 0b0010. + HWCAP_SHA3 Functionality implied by ID_AA64ISAR0_EL1.SHA3 == 0b0001. @@ -159,6 +163,30 @@ HWCAP_SVE Functionality implied by ID_AA64PFR0_EL1.SVE == 0b0001. +HWCAP2_SVE2 + + Functionality implied by ID_AA64ZFR0_EL1.SVEVer == 0b0001. + +HWCAP2_SVEAES + + Functionality implied by ID_AA64ZFR0_EL1.AES == 0b0001. + +HWCAP2_SVEPMULL + + Functionality implied by ID_AA64ZFR0_EL1.AES == 0b0010. + +HWCAP2_SVEBITPERM + + Functionality implied by ID_AA64ZFR0_EL1.BitPerm == 0b0001. + +HWCAP2_SVESHA3 + + Functionality implied by ID_AA64ZFR0_EL1.SHA3 == 0b0001. + +HWCAP2_SVESM4 + + Functionality implied by ID_AA64ZFR0_EL1.SM4 == 0b0001. + HWCAP_ASIMDFHM Functionality implied by ID_AA64ISAR0_EL1.FHM == 0b0001. @@ -194,3 +222,10 @@ HWCAP_PACG Functionality implied by ID_AA64ISAR1_EL1.GPA == 0b0001 or ID_AA64ISAR1_EL1.GPI == 0b0001, as described by Documentation/arm64/pointer-authentication.txt. + + +4. Unused AT_HWCAP bits +----------------------- + +For interoperation with userspace, the kernel guarantees that bits 62 +and 63 of AT_HWCAP will always be returned as 0. diff --git a/Documentation/arm64/silicon-errata.txt b/Documentation/arm64/silicon-errata.txt index d1e2bb801e1b..68d9b74fd751 100644 --- a/Documentation/arm64/silicon-errata.txt +++ b/Documentation/arm64/silicon-errata.txt @@ -61,6 +61,7 @@ stable kernels. | ARM | Cortex-A76 | #1188873 | ARM64_ERRATUM_1188873 | | ARM | Cortex-A76 | #1165522 | ARM64_ERRATUM_1165522 | | ARM | Cortex-A76 | #1286807 | ARM64_ERRATUM_1286807 | +| ARM | Neoverse-N1 | #1188873 | ARM64_ERRATUM_1188873 | | ARM | MMU-500 | #841119,#826419 | N/A | | | | | | | Cavium | ThunderX ITS | #22375, #24313 | CAVIUM_ERRATUM_22375 | @@ -77,6 +78,7 @@ stable kernels. | Hisilicon | Hip0{5,6,7} | #161010101 | HISILICON_ERRATUM_161010101 | | Hisilicon | Hip0{6,7} | #161010701 | N/A | | Hisilicon | Hip07 | #161600802 | HISILICON_ERRATUM_161600802 | +| Hisilicon | Hip08 SMMU PMCG | #162001800 | N/A | | | | | | | Qualcomm Tech. | Kryo/Falkor v1 | E1003 | QCOM_FALKOR_ERRATUM_1003 | | Qualcomm Tech. | Falkor v1 | E1009 | QCOM_FALKOR_ERRATUM_1009 | diff --git a/Documentation/arm64/sve.txt b/Documentation/arm64/sve.txt index 7169a0ec41d8..9940e924a47e 100644 --- a/Documentation/arm64/sve.txt +++ b/Documentation/arm64/sve.txt @@ -34,6 +34,23 @@ model features for SVE is included in Appendix A. following sections: software that needs to verify that those interfaces are present must check for HWCAP_SVE instead. +* On hardware that supports the SVE2 extensions, HWCAP2_SVE2 will also + be reported in the AT_HWCAP2 aux vector entry. In addition to this, + optional extensions to SVE2 may be reported by the presence of: + + HWCAP2_SVE2 + HWCAP2_SVEAES + HWCAP2_SVEPMULL + HWCAP2_SVEBITPERM + HWCAP2_SVESHA3 + HWCAP2_SVESM4 + + This list may be extended over time as the SVE architecture evolves. + + These extensions are also reported via the CPU ID register ID_AA64ZFR0_EL1, + which userspace can read using an MRS instruction. See elf_hwcaps.txt and + cpu-feature-registers.txt for details. + * Debuggers should restrict themselves to interacting with the target via the NT_ARM_SVE regset. The recommended way of detecting support for this regset is to connect to a target process first and then attempt a diff --git a/Documentation/atomic_t.txt b/Documentation/atomic_t.txt index 913396ac5824..dca3fb0554db 100644 --- a/Documentation/atomic_t.txt +++ b/Documentation/atomic_t.txt @@ -56,6 +56,23 @@ Barriers: smp_mb__{before,after}_atomic() +TYPES (signed vs unsigned) +----- + +While atomic_t, atomic_long_t and atomic64_t use int, long and s64 +respectively (for hysterical raisins), the kernel uses -fno-strict-overflow +(which implies -fwrapv) and defines signed overflow to behave like +2s-complement. + +Therefore, an explicitly unsigned variant of the atomic ops is strictly +unnecessary and we can simply cast, there is no UB. + +There was a bug in UBSAN prior to GCC-8 that would generate UB warnings for +signed types. + +With this we also conform to the C/C++ _Atomic behaviour and things like +P1236R1. + SEMANTICS --------- diff --git a/Documentation/core-api/cachetlb.rst b/Documentation/core-api/cachetlb.rst index 6eb9d3f090cd..93cb65d52720 100644 --- a/Documentation/core-api/cachetlb.rst +++ b/Documentation/core-api/cachetlb.rst @@ -101,16 +101,6 @@ changes occur: translations for software managed TLB configurations. The sparc64 port currently does this. -6) ``void tlb_migrate_finish(struct mm_struct *mm)`` - - This interface is called at the end of an explicit - process migration. This interface provides a hook - to allow a platform to update TLB or context-specific - information for the address space. - - The ia64 sn2 platform is one example of a platform - that uses this interface. - Next, we have the cache flushing interfaces. In general, when Linux is changing an existing virtual-->physical mapping to a new value, the sequence will be in one of the following forms:: diff --git a/Documentation/cputopology.txt b/Documentation/cputopology.txt index c6e7e9196a8b..cb61277e2308 100644 --- a/Documentation/cputopology.txt +++ b/Documentation/cputopology.txt @@ -3,79 +3,79 @@ How CPU topology info is exported via sysfs =========================================== Export CPU topology info via sysfs. Items (attributes) are similar -to /proc/cpuinfo output of some architectures: +to /proc/cpuinfo output of some architectures. They reside in +/sys/devices/system/cpu/cpuX/topology/: -1) /sys/devices/system/cpu/cpuX/topology/physical_package_id: +physical_package_id: physical package id of cpuX. Typically corresponds to a physical socket number, but the actual value is architecture and platform dependent. -2) /sys/devices/system/cpu/cpuX/topology/core_id: +core_id: the CPU core ID of cpuX. Typically it is the hardware platform's identifier (rather than the kernel's). The actual value is architecture and platform dependent. -3) /sys/devices/system/cpu/cpuX/topology/book_id: +book_id: the book ID of cpuX. Typically it is the hardware platform's identifier (rather than the kernel's). The actual value is architecture and platform dependent. -4) /sys/devices/system/cpu/cpuX/topology/drawer_id: +drawer_id: the drawer ID of cpuX. Typically it is the hardware platform's identifier (rather than the kernel's). The actual value is architecture and platform dependent. -5) /sys/devices/system/cpu/cpuX/topology/thread_siblings: +thread_siblings: internal kernel map of cpuX's hardware threads within the same core as cpuX. -6) /sys/devices/system/cpu/cpuX/topology/thread_siblings_list: +thread_siblings_list: human-readable list of cpuX's hardware threads within the same core as cpuX. -7) /sys/devices/system/cpu/cpuX/topology/core_siblings: +core_siblings: internal kernel map of cpuX's hardware threads within the same physical_package_id. -8) /sys/devices/system/cpu/cpuX/topology/core_siblings_list: +core_siblings_list: human-readable list of cpuX's hardware threads within the same physical_package_id. -9) /sys/devices/system/cpu/cpuX/topology/book_siblings: +book_siblings: internal kernel map of cpuX's hardware threads within the same book_id. -10) /sys/devices/system/cpu/cpuX/topology/book_siblings_list: +book_siblings_list: human-readable list of cpuX's hardware threads within the same book_id. -11) /sys/devices/system/cpu/cpuX/topology/drawer_siblings: +drawer_siblings: internal kernel map of cpuX's hardware threads within the same drawer_id. -12) /sys/devices/system/cpu/cpuX/topology/drawer_siblings_list: +drawer_siblings_list: human-readable list of cpuX's hardware threads within the same drawer_id. -To implement it in an architecture-neutral way, a new source file, -drivers/base/topology.c, is to export the 6 to 12 attributes. The book -and drawer related sysfs files will only be created if CONFIG_SCHED_BOOK -and CONFIG_SCHED_DRAWER are selected. +Architecture-neutral, drivers/base/topology.c, exports these attributes. +However, the book and drawer related sysfs files will only be created if +CONFIG_SCHED_BOOK and CONFIG_SCHED_DRAWER are selected, respectively. -CONFIG_SCHED_BOOK and CONFIG_DRAWER are currently only used on s390, where -they reflect the cpu and cache hierarchy. +CONFIG_SCHED_BOOK and CONFIG_SCHED_DRAWER are currently only used on s390, +where they reflect the cpu and cache hierarchy. For an architecture to support this feature, it must define some of these macros in include/asm-XXX/topology.h:: @@ -98,10 +98,10 @@ To be consistent on all architectures, include/linux/topology.h provides default definitions for any of the above macros that are not defined by include/asm-XXX/topology.h: -1) physical_package_id: -1 -2) core_id: 0 -3) sibling_cpumask: just the given CPU -4) core_cpumask: just the given CPU +1) topology_physical_package_id: -1 +2) topology_core_id: 0 +3) topology_sibling_cpumask: just the given CPU +4) topology_core_cpumask: just the given CPU For architectures that don't support books (CONFIG_SCHED_BOOK) there are no default definitions for topology_book_id() and topology_book_cpumask(). diff --git a/Documentation/devicetree/bindings/edac/socfpga-eccmgr.txt b/Documentation/devicetree/bindings/edac/socfpga-eccmgr.txt index 5626560a6cfd..8f52206cfd2a 100644 --- a/Documentation/devicetree/bindings/edac/socfpga-eccmgr.txt +++ b/Documentation/devicetree/bindings/edac/socfpga-eccmgr.txt @@ -232,37 +232,152 @@ Example: }; }; -Stratix10 SoCFPGA ECC Manager +Stratix10 SoCFPGA ECC Manager (ARM64) The Stratix10 SoC ECC Manager handles the IRQs for each peripheral -in a shared register similar to the Arria10. However, ECC requires -access to registers that can only be read from Secure Monitor with -SMC calls. Therefore the device tree is slightly different. +in a shared register similar to the Arria10. However, Stratix10 ECC +requires access to registers that can only be read from Secure Monitor +with SMC calls. Therefore the device tree is slightly different. Note +that only 1 interrupt is sent in Stratix10 because the double bit errors +are treated as SErrors in ARM64 instead of IRQs in ARM32. Required Properties: - compatible : Should be "altr,socfpga-s10-ecc-manager" -- interrupts : Should be single bit error interrupt, then double bit error - interrupt. +- altr,sysgr-syscon : phandle to Stratix10 System Manager Block + containing the ECC manager registers. +- interrupts : Should be single bit error interrupt. - interrupt-controller : boolean indicator that ECC Manager is an interrupt controller - #interrupt-cells : must be set to 2. +- #address-cells: must be 1 +- #size-cells: must be 1 +- ranges : standard definition, should translate from local addresses Subcomponents: SDRAM ECC Required Properties: - compatible : Should be "altr,sdram-edac-s10" -- interrupts : Should be single bit error interrupt, then double bit error - interrupt, in this order. +- interrupts : Should be single bit error interrupt. + +On-Chip RAM ECC +Required Properties: +- compatible : Should be "altr,socfpga-s10-ocram-ecc" +- reg : Address and size for ECC block registers. +- altr,ecc-parent : phandle to parent OCRAM node. +- interrupts : Should be single bit error interrupt. + +Ethernet FIFO ECC +Required Properties: +- compatible : Should be "altr,socfpga-s10-eth-mac-ecc" +- reg : Address and size for ECC block registers. +- altr,ecc-parent : phandle to parent Ethernet node. +- interrupts : Should be single bit error interrupt. + +NAND FIFO ECC +Required Properties: +- compatible : Should be "altr,socfpga-s10-nand-ecc" +- reg : Address and size for ECC block registers. +- altr,ecc-parent : phandle to parent NAND node. +- interrupts : Should be single bit error interrupt. + +DMA FIFO ECC +Required Properties: +- compatible : Should be "altr,socfpga-s10-dma-ecc" +- reg : Address and size for ECC block registers. +- altr,ecc-parent : phandle to parent DMA node. +- interrupts : Should be single bit error interrupt. + +USB FIFO ECC +Required Properties: +- compatible : Should be "altr,socfpga-s10-usb-ecc" +- reg : Address and size for ECC block registers. +- altr,ecc-parent : phandle to parent USB node. +- interrupts : Should be single bit error interrupt. + +SDMMC FIFO ECC +Required Properties: +- compatible : Should be "altr,socfpga-s10-sdmmc-ecc" +- reg : Address and size for ECC block registers. +- altr,ecc-parent : phandle to parent SD/MMC node. +- interrupts : Should be single bit error interrupt for port A + and then single bit error interrupt for port B. Example: eccmgr { compatible = "altr,socfpga-s10-ecc-manager"; - interrupts = <0 15 4>, <0 95 4>; + altr,sysmgr-syscon = <&sysmgr>; + #address-cells = <1>; + #size-cells = <1>; + interrupts = <0 15 4>; interrupt-controller; #interrupt-cells = <2>; + ranges; sdramedac { compatible = "altr,sdram-edac-s10"; - interrupts = <16 4>, <48 4>; + interrupts = <16 IRQ_TYPE_LEVEL_HIGH>; + }; + + ocram-ecc@ff8cc000 { + compatible = "altr,socfpga-s10-ocram-ecc"; + reg = <ff8cc000 0x100>; + altr,ecc-parent = <&ocram>; + interrupts = <1 IRQ_TYPE_LEVEL_HIGH>; + }; + + emac0-rx-ecc@ff8c0000 { + compatible = "altr,socfpga-s10-eth-mac-ecc"; + reg = <0xff8c0000 0x100>; + altr,ecc-parent = <&gmac0>; + interrupts = <4 IRQ_TYPE_LEVEL_HIGH>; + }; + + emac0-tx-ecc@ff8c0400 { + compatible = "altr,socfpga-s10-eth-mac-ecc"; + reg = <0xff8c0400 0x100>; + altr,ecc-parent = <&gmac0>; + interrupts = <5 IRQ_TYPE_LEVEL_HIGH>' + }; + + nand-buf-ecc@ff8c8000 { + compatible = "altr,socfpga-s10-nand-ecc"; + reg = <0xff8c8000 0x100>; + altr,ecc-parent = <&nand>; + interrupts = <11 IRQ_TYPE_LEVEL_HIGH>; + }; + + nand-rd-ecc@ff8c8400 { + compatible = "altr,socfpga-s10-nand-ecc"; + reg = <0xff8c8400 0x100>; + altr,ecc-parent = <&nand>; + interrupts = <13 IRQ_TYPE_LEVEL_HIGH>; + }; + + nand-wr-ecc@ff8c8800 { + compatible = "altr,socfpga-s10-nand-ecc"; + reg = <0xff8c8800 0x100>; + altr,ecc-parent = <&nand>; + interrupts = <12 IRQ_TYPE_LEVEL_HIGH>; + }; + + dma-ecc@ff8c9000 { + compatible = "altr,socfpga-s10-dma-ecc"; + reg = <0xff8c9000 0x100>; + altr,ecc-parent = <&pdma>; + interrupts = <10 IRQ_TYPE_LEVEL_HIGH>; + + usb0-ecc@ff8c4000 { + compatible = "altr,socfpga-s10-usb-ecc"; + reg = <0xff8c4000 0x100>; + altr,ecc-parent = <&usb0>; + interrupts = <2 IRQ_TYPE_LEVEL_HIGH>; + }; + + sdmmc-ecc@ff8c8c00 { + compatible = "altr,socfpga-s10-sdmmc-ecc"; + reg = <0xff8c8c00 0x100>; + altr,ecc-parent = <&mmc>; + interrupts = <14 IRQ_TYPE_LEVEL_HIGH>, + <15 IRQ_TYPE_LEVEL_HIGH>; }; }; diff --git a/Documentation/devicetree/bindings/net/davinci_emac.txt b/Documentation/devicetree/bindings/net/davinci_emac.txt index 24c5cdaba8d2..ca83dcc84fb8 100644 --- a/Documentation/devicetree/bindings/net/davinci_emac.txt +++ b/Documentation/devicetree/bindings/net/davinci_emac.txt @@ -20,6 +20,8 @@ Required properties: Optional properties: - phy-handle: See ethernet.txt file in the same directory. If absent, davinci_emac driver defaults to 100/FULL. +- nvmem-cells: phandle, reference to an nvmem node for the MAC address +- nvmem-cell-names: string, should be "mac-address" if nvmem is to be used - ti,davinci-rmii-en: 1 byte, 1 means use RMII - ti,davinci-no-bd-ram: boolean, does EMAC have BD RAM? diff --git a/Documentation/devicetree/bindings/net/ethernet.txt b/Documentation/devicetree/bindings/net/ethernet.txt index cfc376bc977a..a68621580584 100644 --- a/Documentation/devicetree/bindings/net/ethernet.txt +++ b/Documentation/devicetree/bindings/net/ethernet.txt @@ -10,15 +10,14 @@ Documentation/devicetree/bindings/phy/phy-bindings.txt. the boot program; should be used in cases where the MAC address assigned to the device by the boot program is different from the "local-mac-address" property; -- nvmem-cells: phandle, reference to an nvmem node for the MAC address; -- nvmem-cell-names: string, should be "mac-address" if nvmem is to be used; - max-speed: number, specifies maximum speed in Mbit/s supported by the device; - max-frame-size: number, maximum transfer unit (IEEE defined MTU), rather than the maximum frame size (there's contradiction in the Devicetree Specification). - phy-mode: string, operation mode of the PHY interface. This is now a de-facto standard property; supported values are: - * "internal" + * "internal" (Internal means there is not a standard bus between the MAC and + the PHY, something proprietary is being used to embed the PHY in the MAC.) * "mii" * "gmii" * "sgmii" diff --git a/Documentation/devicetree/bindings/net/macb.txt b/Documentation/devicetree/bindings/net/macb.txt index 174f292d8a3e..8b80515729d7 100644 --- a/Documentation/devicetree/bindings/net/macb.txt +++ b/Documentation/devicetree/bindings/net/macb.txt @@ -26,6 +26,10 @@ Required properties: Optional elements: 'tsu_clk' - clocks: Phandles to input clocks. +Optional properties: +- nvmem-cells: phandle, reference to an nvmem node for the MAC address +- nvmem-cell-names: string, should be "mac-address" if nvmem is to be used + Optional properties for PHY child node: - reset-gpios : Should specify the gpio for phy reset - magic-packet : If present, indicates that the hardware supports waking diff --git a/Documentation/driver-api/acpi/index.rst b/Documentation/driver-api/acpi/index.rst new file mode 100644 index 000000000000..ace0008e54c2 --- /dev/null +++ b/Documentation/driver-api/acpi/index.rst @@ -0,0 +1,9 @@ +============ +ACPI Support +============ + +.. toctree:: + :maxdepth: 2 + + linuxized-acpica + scan_handlers diff --git a/Documentation/acpi/linuxized-acpica.txt b/Documentation/driver-api/acpi/linuxized-acpica.rst index 3ad7b0dfb083..0ca8f1538519 100644 --- a/Documentation/acpi/linuxized-acpica.txt +++ b/Documentation/driver-api/acpi/linuxized-acpica.rst @@ -1,31 +1,37 @@ +.. SPDX-License-Identifier: GPL-2.0 +.. include:: <isonum.txt> + +============================================================ Linuxized ACPICA - Introduction to ACPICA Release Automation +============================================================ -Copyright (C) 2013-2016, Intel Corporation -Author: Lv Zheng <lv.zheng@intel.com> +:Copyright: |copy| 2013-2016, Intel Corporation +:Author: Lv Zheng <lv.zheng@intel.com> -Abstract: +Abstract +======== This document describes the ACPICA project and the relationship between ACPICA and Linux. It also describes how ACPICA code in drivers/acpi/acpica, include/acpi and tools/power/acpi is automatically updated to follow the upstream. +ACPICA Project +============== -1. ACPICA Project - - The ACPI Component Architecture (ACPICA) project provides an operating - system (OS)-independent reference implementation of the Advanced - Configuration and Power Interface Specification (ACPI). It has been - adapted by various host OSes. By directly integrating ACPICA, Linux can - also benefit from the application experiences of ACPICA from other host - OSes. +The ACPI Component Architecture (ACPICA) project provides an operating +system (OS)-independent reference implementation of the Advanced +Configuration and Power Interface Specification (ACPI). It has been +adapted by various host OSes. By directly integrating ACPICA, Linux can +also benefit from the application experiences of ACPICA from other host +OSes. - The homepage of ACPICA project is: www.acpica.org, it is maintained and - supported by Intel Corporation. +The homepage of ACPICA project is: www.acpica.org, it is maintained and +supported by Intel Corporation. - The following figure depicts the Linux ACPI subsystem where the ACPICA - adaptation is included: +The following figure depicts the Linux ACPI subsystem where the ACPICA +adaptation is included:: +---------------------------------------------------------+ | | @@ -71,21 +77,27 @@ upstream. Figure 1. Linux ACPI Software Components - NOTE: +.. note:: A. OS Service Layer - Provided by Linux to offer OS dependent implementation of the predefined ACPICA interfaces (acpi_os_*). + :: + include/acpi/acpiosxf.h drivers/acpi/osl.c include/acpi/platform include/asm/acenv.h B. ACPICA Functionality - Released from ACPICA code base to offer OS independent implementation of the ACPICA interfaces (acpi_*). + :: + drivers/acpi/acpica include/acpi/ac*.h tools/power/acpi C. Linux/ACPI Functionality - Providing Linux specific ACPI functionality to the other Linux kernel subsystems and user space programs. + :: + drivers/acpi include/linux/acpi.h include/linux/acpi*.h @@ -95,24 +107,27 @@ upstream. ACPI subsystem to offer architecture specific implementation of the ACPI interfaces. They are Linux specific components and are out of the scope of this document. + :: + include/asm/acpi.h include/asm/acpi*.h arch/*/acpi -2. ACPICA Release +ACPICA Release +============== - The ACPICA project maintains its code base at the following repository URL: - https://github.com/acpica/acpica.git. As a rule, a release is made every - month. +The ACPICA project maintains its code base at the following repository URL: +https://github.com/acpica/acpica.git. As a rule, a release is made every +month. - As the coding style adopted by the ACPICA project is not acceptable by - Linux, there is a release process to convert the ACPICA git commits into - Linux patches. The patches generated by this process are referred to as - "linuxized ACPICA patches". The release process is carried out on a local - copy the ACPICA git repository. Each commit in the monthly release is - converted into a linuxized ACPICA patch. Together, they form the monthly - ACPICA release patchset for the Linux ACPI community. This process is - illustrated in the following figure: +As the coding style adopted by the ACPICA project is not acceptable by +Linux, there is a release process to convert the ACPICA git commits into +Linux patches. The patches generated by this process are referred to as +"linuxized ACPICA patches". The release process is carried out on a local +copy the ACPICA git repository. Each commit in the monthly release is +converted into a linuxized ACPICA patch. Together, they form the monthly +ACPICA release patchset for the Linux ACPI community. This process is +illustrated in the following figure:: +-----------------------------+ | acpica / master (-) commits | @@ -153,7 +168,7 @@ upstream. Figure 2. ACPICA -> Linux Upstream Process - NOTE: +.. note:: A. Linuxize Utilities - Provided by the ACPICA repository, including a utility located in source/tools/acpisrc folder and a number of scripts located in generate/linux folder. @@ -170,19 +185,20 @@ upstream. following kernel configuration options: CONFIG_ACPI/CONFIG_ACPI_DEBUG/CONFIG_ACPI_DEBUGGER -3. ACPICA Divergences +ACPICA Divergences +================== - Ideally, all of the ACPICA commits should be converted into Linux patches - automatically without manual modifications, the "linux / master" tree should - contain the ACPICA code that exactly corresponds to the ACPICA code - contained in "new linuxized acpica" tree and it should be possible to run - the release process fully automatically. +Ideally, all of the ACPICA commits should be converted into Linux patches +automatically without manual modifications, the "linux / master" tree should +contain the ACPICA code that exactly corresponds to the ACPICA code +contained in "new linuxized acpica" tree and it should be possible to run +the release process fully automatically. - As a matter of fact, however, there are source code differences between - the ACPICA code in Linux and the upstream ACPICA code, referred to as - "ACPICA Divergences". +As a matter of fact, however, there are source code differences between +the ACPICA code in Linux and the upstream ACPICA code, referred to as +"ACPICA Divergences". - The various sources of ACPICA divergences include: +The various sources of ACPICA divergences include: 1. Legacy divergences - Before the current ACPICA release process was established, there already had been divergences between Linux and ACPICA. Over the past several years those divergences have been greatly @@ -213,11 +229,12 @@ upstream. rebased on the ACPICA side in order to offer better solutions, new ACPICA divergences are generated. -4. ACPICA Development +ACPICA Development +================== - This paragraph guides Linux developers to use the ACPICA upstream release - utilities to obtain Linux patches corresponding to upstream ACPICA commits - before they become available from the ACPICA release process. +This paragraph guides Linux developers to use the ACPICA upstream release +utilities to obtain Linux patches corresponding to upstream ACPICA commits +before they become available from the ACPICA release process. 1. Cherry-pick an ACPICA commit @@ -225,7 +242,7 @@ upstream. you want to cherry pick must be committed into the local repository. Then the gen-patch.sh command can help to cherry-pick an ACPICA commit - from the ACPICA local repository: + from the ACPICA local repository:: $ git clone https://github.com/acpica/acpica $ cd acpica @@ -240,7 +257,7 @@ upstream. changes that haven't been applied to Linux yet. You can generate the ACPICA release series yourself and rebase your code on - top of the generated ACPICA release patches: + top of the generated ACPICA release patches:: $ git clone https://github.com/acpica/acpica $ cd acpica @@ -254,7 +271,7 @@ upstream. 3. Inspect the current divergences If you have local copies of both Linux and upstream ACPICA, you can generate - a diff file indicating the state of the current divergences: + a diff file indicating the state of the current divergences:: # git clone https://github.com/acpica/acpica # git clone http://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git diff --git a/Documentation/acpi/scan_handlers.txt b/Documentation/driver-api/acpi/scan_handlers.rst index 3246ccf15992..7a197b3a33fc 100644 --- a/Documentation/acpi/scan_handlers.txt +++ b/Documentation/driver-api/acpi/scan_handlers.rst @@ -1,7 +1,13 @@ +.. SPDX-License-Identifier: GPL-2.0 +.. include:: <isonum.txt> + +================== ACPI Scan Handlers +================== + +:Copyright: |copy| 2012, Intel Corporation -Copyright (C) 2012, Intel Corporation -Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com> +:Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com> During system initialization and ACPI-based device hot-add, the ACPI namespace is scanned in search of device objects that generally represent various pieces @@ -30,14 +36,14 @@ to configure that link so that the kernel can use it. Those additional configuration tasks usually depend on the type of the hardware component represented by the given device node which can be determined on the basis of the device node's hardware ID (HID). They are performed by objects -called ACPI scan handlers represented by the following structure: +called ACPI scan handlers represented by the following structure:: -struct acpi_scan_handler { - const struct acpi_device_id *ids; - struct list_head list_node; - int (*attach)(struct acpi_device *dev, const struct acpi_device_id *id); - void (*detach)(struct acpi_device *dev); -}; + struct acpi_scan_handler { + const struct acpi_device_id *ids; + struct list_head list_node; + int (*attach)(struct acpi_device *dev, const struct acpi_device_id *id); + void (*detach)(struct acpi_device *dev); + }; where ids is the list of IDs of device nodes the given handler is supposed to take care of, list_node is the hook to the global list of ACPI scan handlers diff --git a/Documentation/driver-api/device-io.rst b/Documentation/driver-api/device-io.rst index b00b23903078..0e389378f71d 100644 --- a/Documentation/driver-api/device-io.rst +++ b/Documentation/driver-api/device-io.rst @@ -103,51 +103,6 @@ continuing execution:: ha->flags.ints_enabled = 0; } -In addition to write posting, on some large multiprocessing systems -(e.g. SGI Challenge, Origin and Altix machines) posted writes won't be -strongly ordered coming from different CPUs. Thus it's important to -properly protect parts of your driver that do memory-mapped writes with -locks and use the :c:func:`mmiowb()` to make sure they arrive in the -order intended. Issuing a regular readX() will also ensure write ordering, -but should only be used when the -driver has to be sure that the write has actually arrived at the device -(not that it's simply ordered with respect to other writes), since a -full readX() is a relatively expensive operation. - -Generally, one should use :c:func:`mmiowb()` prior to releasing a spinlock -that protects regions using :c:func:`writeb()` or similar functions that -aren't surrounded by readb() calls, which will ensure ordering -and flushing. The following pseudocode illustrates what might occur if -write ordering isn't guaranteed via :c:func:`mmiowb()` or one of the -readX() functions:: - - CPU A: spin_lock_irqsave(&dev_lock, flags) - CPU A: ... - CPU A: writel(newval, ring_ptr); - CPU A: spin_unlock_irqrestore(&dev_lock, flags) - ... - CPU B: spin_lock_irqsave(&dev_lock, flags) - CPU B: writel(newval2, ring_ptr); - CPU B: ... - CPU B: spin_unlock_irqrestore(&dev_lock, flags) - -In the case above, newval2 could be written to ring_ptr before newval. -Fixing it is easy though:: - - CPU A: spin_lock_irqsave(&dev_lock, flags) - CPU A: ... - CPU A: writel(newval, ring_ptr); - CPU A: mmiowb(); /* ensure no other writes beat us to the device */ - CPU A: spin_unlock_irqrestore(&dev_lock, flags) - ... - CPU B: spin_lock_irqsave(&dev_lock, flags) - CPU B: writel(newval2, ring_ptr); - CPU B: ... - CPU B: mmiowb(); - CPU B: spin_unlock_irqrestore(&dev_lock, flags) - -See tg3.c for a real world example of how to use :c:func:`mmiowb()` - PCI ordering rules also guarantee that PIO read responses arrive after any outstanding DMA writes from that bus, since for some devices the result of a readb() call may signal to the driver that a DMA transaction is diff --git a/Documentation/driver-api/index.rst b/Documentation/driver-api/index.rst index c0b600ed9961..aa87075c7846 100644 --- a/Documentation/driver-api/index.rst +++ b/Documentation/driver-api/index.rst @@ -56,6 +56,7 @@ available subsections can be seen below. slimbus soundwire/index fpga/index + acpi/index .. only:: subproject and html diff --git a/Documentation/driver-api/pci/p2pdma.rst b/Documentation/driver-api/pci/p2pdma.rst index 6d85b5a2598d..44deb52beeb4 100644 --- a/Documentation/driver-api/pci/p2pdma.rst +++ b/Documentation/driver-api/pci/p2pdma.rst @@ -132,10 +132,6 @@ precludes passing these pages to userspace. P2P memory is also technically IO memory but should never have any side effects behind it. Thus, the order of loads and stores should not be important and ioreadX(), iowriteX() and friends should not be necessary. -However, as the memory is not cache coherent, if access ever needs to -be protected by a spinlock then :c:func:`mmiowb()` must be used before -unlocking the lock. (See ACQUIRES VS I/O ACCESSES in -Documentation/memory-barriers.txt) P2P DMA Support Library diff --git a/Documentation/driver-api/pm/cpuidle.rst b/Documentation/driver-api/pm/cpuidle.rst index 5842ab621a58..006cf6db40c6 100644 --- a/Documentation/driver-api/pm/cpuidle.rst +++ b/Documentation/driver-api/pm/cpuidle.rst @@ -1,3 +1,6 @@ +.. SPDX-License-Identifier: GPL-2.0 +.. include:: <isonum.txt> + .. |struct cpuidle_governor| replace:: :c:type:`struct cpuidle_governor <cpuidle_governor>` .. |struct cpuidle_device| replace:: :c:type:`struct cpuidle_device <cpuidle_device>` .. |struct cpuidle_driver| replace:: :c:type:`struct cpuidle_driver <cpuidle_driver>` @@ -7,9 +10,9 @@ CPU Idle Time Management ======================== -:: +:Copyright: |copy| 2019 Intel Corporation - Copyright (c) 2019 Intel Corp., Rafael J. Wysocki <rafael.j.wysocki@intel.com> +:Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com> CPU Idle Time Management Subsystem diff --git a/Documentation/driver-api/pm/devices.rst b/Documentation/driver-api/pm/devices.rst index 090c151aa86b..30835683616a 100644 --- a/Documentation/driver-api/pm/devices.rst +++ b/Documentation/driver-api/pm/devices.rst @@ -1,3 +1,6 @@ +.. SPDX-License-Identifier: GPL-2.0 +.. include:: <isonum.txt> + .. |struct dev_pm_ops| replace:: :c:type:`struct dev_pm_ops <dev_pm_ops>` .. |struct dev_pm_domain| replace:: :c:type:`struct dev_pm_domain <dev_pm_domain>` .. |struct bus_type| replace:: :c:type:`struct bus_type <bus_type>` @@ -12,11 +15,12 @@ Device Power Management Basics ============================== -:: +:Copyright: |copy| 2010-2011 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. +:Copyright: |copy| 2010 Alan Stern <stern@rowland.harvard.edu> +:Copyright: |copy| 2016 Intel Corporation + +:Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com> - Copyright (c) 2010-2011 Rafael J. Wysocki <rjw@sisk.pl>, Novell Inc. - Copyright (c) 2010 Alan Stern <stern@rowland.harvard.edu> - Copyright (c) 2016 Intel Corp., Rafael J. Wysocki <rafael.j.wysocki@intel.com> Most of the code in Linux is device drivers, so most of the Linux power management (PM) code is also driver-specific. Most drivers will do very diff --git a/Documentation/driver-api/pm/index.rst b/Documentation/driver-api/pm/index.rst index 56975c6bc789..c2a9ef8d115c 100644 --- a/Documentation/driver-api/pm/index.rst +++ b/Documentation/driver-api/pm/index.rst @@ -1,3 +1,5 @@ +.. SPDX-License-Identifier: GPL-2.0 + =============================== CPU and Device Power Management =============================== diff --git a/Documentation/driver-api/pm/notifiers.rst b/Documentation/driver-api/pm/notifiers.rst index 62f860026992..186435c43b77 100644 --- a/Documentation/driver-api/pm/notifiers.rst +++ b/Documentation/driver-api/pm/notifiers.rst @@ -1,10 +1,14 @@ +.. SPDX-License-Identifier: GPL-2.0 +.. include:: <isonum.txt> + ============================= Suspend/Hibernation Notifiers ============================= -:: +:Copyright: |copy| 2016 Intel Corporation + +:Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com> - Copyright (c) 2016 Intel Corp., Rafael J. Wysocki <rafael.j.wysocki@intel.com> There are some operations that subsystems or drivers may want to carry out before hibernation/suspend or after restore/resume, but they require the system diff --git a/Documentation/driver-api/pm/types.rst b/Documentation/driver-api/pm/types.rst index 3ebdecc54104..73a231caf764 100644 --- a/Documentation/driver-api/pm/types.rst +++ b/Documentation/driver-api/pm/types.rst @@ -1,3 +1,5 @@ +.. SPDX-License-Identifier: GPL-2.0 + ================================== Device Power Management Data Types ================================== diff --git a/Documentation/driver-api/usb/power-management.rst b/Documentation/driver-api/usb/power-management.rst index 79beb807996b..4a74cf6f2797 100644 --- a/Documentation/driver-api/usb/power-management.rst +++ b/Documentation/driver-api/usb/power-management.rst @@ -370,11 +370,15 @@ autosuspend the interface's device. When the usage counter is = 0 then the interface is considered to be idle, and the kernel may autosuspend the device. -Drivers need not be concerned about balancing changes to the usage -counter; the USB core will undo any remaining "get"s when a driver -is unbound from its interface. As a corollary, drivers must not call -any of the ``usb_autopm_*`` functions after their ``disconnect`` -routine has returned. +Drivers must be careful to balance their overall changes to the usage +counter. Unbalanced "get"s will remain in effect when a driver is +unbound from its interface, preventing the device from going into +runtime suspend should the interface be bound to a driver again. On +the other hand, drivers are allowed to achieve this balance by calling +the ``usb_autopm_*`` functions even after their ``disconnect`` routine +has returned -- say from within a work-queue routine -- provided they +retain an active reference to the interface (via ``usb_get_intf`` and +``usb_put_intf``). Drivers using the async routines are responsible for their own synchronization and mutual exclusion. diff --git a/Documentation/features/time/modern-timekeeping/arch-support.txt b/Documentation/features/time/modern-timekeeping/arch-support.txt index 2855dfe2464d..1d46da165b75 100644 --- a/Documentation/features/time/modern-timekeeping/arch-support.txt +++ b/Documentation/features/time/modern-timekeeping/arch-support.txt @@ -15,7 +15,7 @@ | h8300: | ok | | hexagon: | ok | | ia64: | ok | - | m68k: | TODO | + | m68k: | ok | | microblaze: | ok | | mips: | ok | | nds32: | ok | diff --git a/Documentation/acpi/DSD-properties-rules.txt b/Documentation/firmware-guide/acpi/DSD-properties-rules.rst index 3e4862bdad98..4306f29b6103 100644 --- a/Documentation/acpi/DSD-properties-rules.txt +++ b/Documentation/firmware-guide/acpi/DSD-properties-rules.rst @@ -1,8 +1,11 @@ +.. SPDX-License-Identifier: GPL-2.0 + +================================== _DSD Device Properties Usage Rules ----------------------------------- +================================== Properties, Property Sets and Property Subsets ----------------------------------------------- +============================================== The _DSD (Device Specific Data) configuration object, introduced in ACPI 5.1, allows any type of device configuration data to be provided via the ACPI @@ -18,7 +21,7 @@ specific type) associated with it. In the ACPI _DSD context it is an element of the sub-package following the generic Device Properties UUID in the _DSD return package as specified in the -Device Properties UUID definition document [1]. +Device Properties UUID definition document [1]_. It also may be regarded as the definition of a key and the associated data type that can be returned by _DSD in the Device Properties UUID sub-package for a @@ -33,14 +36,14 @@ Property subsets are nested collections of properties. Each of them is associated with an additional key (name) allowing the subset to be referred to as a whole (and to be treated as a separate entity). The canonical representation of property subsets is via the mechanism specified in the -Hierarchical Properties Extension UUID definition document [2]. +Hierarchical Properties Extension UUID definition document [2]_. Property sets may be hierarchical. That is, a property set may contain multiple property subsets that each may contain property subsets of its own and so on. General Validity Rule for Property Sets ---------------------------------------- +======================================= Valid property sets must follow the guidance given by the Device Properties UUID definition document [1]. @@ -73,7 +76,7 @@ suitable for the ACPI environment and consequently they cannot belong to a valid property set. Property Sets and Device Tree Bindings --------------------------------------- +====================================== It often is useful to make _DSD return property sets that follow Device Tree bindings. @@ -91,7 +94,7 @@ expected to automatically work in the ACPI environment regardless of their contents. References ----------- +========== -[1] http://www.uefi.org/sites/default/files/resources/_DSD-device-properties-UUID.pdf -[2] http://www.uefi.org/sites/default/files/resources/_DSD-hierarchical-data-extension-UUID-v1.1.pdf +.. [1] http://www.uefi.org/sites/default/files/resources/_DSD-device-properties-UUID.pdf +.. [2] http://www.uefi.org/sites/default/files/resources/_DSD-hierarchical-data-extension-UUID-v1.1.pdf diff --git a/Documentation/acpi/acpi-lid.txt b/Documentation/firmware-guide/acpi/acpi-lid.rst index effe7af3a5af..874ce0ed340d 100644 --- a/Documentation/acpi/acpi-lid.txt +++ b/Documentation/firmware-guide/acpi/acpi-lid.rst @@ -1,13 +1,18 @@ -Special Usage Model of the ACPI Control Method Lid Device +.. SPDX-License-Identifier: GPL-2.0 +.. include:: <isonum.txt> -Copyright (C) 2016, Intel Corporation -Author: Lv Zheng <lv.zheng@intel.com> +========================================================= +Special Usage Model of the ACPI Control Method Lid Device +========================================================= +:Copyright: |copy| 2016, Intel Corporation -Abstract: +:Author: Lv Zheng <lv.zheng@intel.com> -Platforms containing lids convey lid state (open/close) to OSPMs using a -control method lid device. To implement this, the AML tables issue +Abstract +======== +Platforms containing lids convey lid state (open/close) to OSPMs +using a control method lid device. To implement this, the AML tables issue Notify(lid_device, 0x80) to notify the OSPMs whenever the lid state has changed. The _LID control method for the lid device must be implemented to report the "current" state of the lid as either "opened" or "closed". @@ -19,7 +24,8 @@ taken into account. This document describes the restrictions and the expections of the Linux ACPI lid device driver. -1. Restrictions of the returning value of the _LID control method +Restrictions of the returning value of the _LID control method +============================================================== The _LID control method is described to return the "current" lid state. However the word of "current" has ambiguity, some buggy AML tables return @@ -30,7 +36,8 @@ initial returning value. When the AML tables implement this control method with cached value, the initial returning value is likely not reliable. There are platforms always retun "closed" as initial lid state. -2. Restrictions of the lid state change notifications +Restrictions of the lid state change notifications +================================================== There are buggy AML tables never notifying when the lid device state is changed to "opened". Thus the "opened" notification is not guaranteed. But @@ -39,18 +46,22 @@ state is changed to "closed". The "closed" notification is normally used to trigger some system power saving operations on Windows. Since it is fully tested, it is reliable from all AML tables. -3. Expections for the userspace users of the ACPI lid device driver +Expections for the userspace users of the ACPI lid device driver +================================================================ The ACPI button driver exports the lid state to the userspace via the -following file: +following file:: + /proc/acpi/button/lid/LID0/state + This file actually calls the _LID control method described above. And given the previous explanation, it is not reliable enough on some platforms. So it is advised for the userspace program to not to solely rely on this file to determine the actual lid state. The ACPI button driver emits the following input event to the userspace: - SW_LID + * SW_LID + The ACPI lid device driver is implemented to try to deliver the platform triggered events to the userspace. However, given the fact that the buggy firmware cannot make sure "opened"/"closed" events are paired, the ACPI @@ -59,20 +70,25 @@ button driver uses the following 3 modes in order not to trigger issues. If the userspace hasn't been prepared to ignore the unreliable "opened" events and the unreliable initial state notification, Linux users can use the following kernel parameters to handle the possible issues: + A. button.lid_init_state=method: When this option is specified, the ACPI button driver reports the initial lid state using the returning value of the _LID control method and whether the "opened"/"closed" events are paired fully relies on the firmware implementation. + This option can be used to fix some platforms where the returning value of the _LID control method is reliable but the initial lid state notification is missing. + This option is the default behavior during the period the userspace isn't ready to handle the buggy AML tables. + B. button.lid_init_state=open: When this option is specified, the ACPI button driver always reports the initial lid state as "opened" and whether the "opened"/"closed" events are paired fully relies on the firmware implementation. + This may fix some platforms where the returning value of the _LID control method is not reliable and the initial lid state notification is missing. @@ -80,6 +96,7 @@ B. button.lid_init_state=open: If the userspace has been prepared to ignore the unreliable "opened" events and the unreliable initial state notification, Linux users should always use the following kernel parameter: + C. button.lid_init_state=ignore: When this option is specified, the ACPI button driver never reports the initial lid state and there is a compensation mechanism implemented to @@ -89,6 +106,7 @@ C. button.lid_init_state=ignore: notifications can be delivered to the userspace when the lid is actually opens given that some AML tables do not send "opened" notifications reliably. + In this mode, if everything is correctly implemented by the platform firmware, the old userspace programs should still work. Otherwise, the new userspace programs are required to work with the ACPI button driver. diff --git a/Documentation/firmware-guide/acpi/aml-debugger.rst b/Documentation/firmware-guide/acpi/aml-debugger.rst new file mode 100644 index 000000000000..a889d43bc6c5 --- /dev/null +++ b/Documentation/firmware-guide/acpi/aml-debugger.rst @@ -0,0 +1,75 @@ +.. SPDX-License-Identifier: GPL-2.0 +.. include:: <isonum.txt> + +================ +The AML Debugger +================ + +:Copyright: |copy| 2016, Intel Corporation +:Author: Lv Zheng <lv.zheng@intel.com> + + +This document describes the usage of the AML debugger embedded in the Linux +kernel. + +1. Build the debugger +===================== + +The following kernel configuration items are required to enable the AML +debugger interface from the Linux kernel:: + + CONFIG_ACPI_DEBUGGER=y + CONFIG_ACPI_DEBUGGER_USER=m + +The userspace utilities can be built from the kernel source tree using +the following commands:: + + $ cd tools + $ make acpi + +The resultant userspace tool binary is then located at:: + + tools/power/acpi/acpidbg + +It can be installed to system directories by running "make install" (as a +sufficiently privileged user). + +2. Start the userspace debugger interface +========================================= + +After booting the kernel with the debugger built-in, the debugger can be +started by using the following commands:: + + # mount -t debugfs none /sys/kernel/debug + # modprobe acpi_dbg + # tools/power/acpi/acpidbg + +That spawns the interactive AML debugger environment where you can execute +debugger commands. + +The commands are documented in the "ACPICA Overview and Programmer Reference" +that can be downloaded from + +https://acpica.org/documentation + +The detailed debugger commands reference is located in Chapter 12 "ACPICA +Debugger Reference". The "help" command can be used for a quick reference. + +3. Stop the userspace debugger interface +======================================== + +The interactive debugger interface can be closed by pressing Ctrl+C or using +the "quit" or "exit" commands. When finished, unload the module with:: + + # rmmod acpi_dbg + +The module unloading may fail if there is an acpidbg instance running. + +4. Run the debugger in a script +=============================== + +It may be useful to run the AML debugger in a test script. "acpidbg" supports +this in a special "batch" mode. For example, the following command outputs +the entire ACPI namespace:: + + # acpidbg -b "namespace" diff --git a/Documentation/acpi/apei/einj.txt b/Documentation/firmware-guide/acpi/apei/einj.rst index e550c8b98139..e588bccf5158 100644 --- a/Documentation/acpi/apei/einj.txt +++ b/Documentation/firmware-guide/acpi/apei/einj.rst @@ -1,13 +1,16 @@ - APEI Error INJection - ~~~~~~~~~~~~~~~~~~~~ +.. SPDX-License-Identifier: GPL-2.0 + +==================== +APEI Error INJection +==================== EINJ provides a hardware error injection mechanism. It is very useful for debugging and testing APEI and RAS features in general. You need to check whether your BIOS supports EINJ first. For that, look -for early boot messages similar to this one: +for early boot messages similar to this one:: -ACPI: EINJ 0x000000007370A000 000150 (v01 INTEL 00000001 INTL 00000001) + ACPI: EINJ 0x000000007370A000 000150 (v01 INTEL 00000001 INTL 00000001) which shows that the BIOS is exposing an EINJ table - it is the mechanism through which the injection is done. @@ -23,11 +26,11 @@ order to see the APEI,EINJ,... functionality supported and exposed by the BIOS menu. To use EINJ, make sure the following are options enabled in your kernel -configuration: +configuration:: -CONFIG_DEBUG_FS -CONFIG_ACPI_APEI -CONFIG_ACPI_APEI_EINJ + CONFIG_DEBUG_FS + CONFIG_ACPI_APEI + CONFIG_ACPI_APEI_EINJ The EINJ user interface is in <debugfs mount point>/apei/einj. @@ -37,20 +40,22 @@ The following files belong to it: This file shows which error types are supported: + ================ =================================== Error Type Value Error Description - ================ ================= - 0x00000001 Processor Correctable - 0x00000002 Processor Uncorrectable non-fatal - 0x00000004 Processor Uncorrectable fatal - 0x00000008 Memory Correctable - 0x00000010 Memory Uncorrectable non-fatal - 0x00000020 Memory Uncorrectable fatal - 0x00000040 PCI Express Correctable - 0x00000080 PCI Express Uncorrectable fatal - 0x00000100 PCI Express Uncorrectable non-fatal - 0x00000200 Platform Correctable - 0x00000400 Platform Uncorrectable non-fatal - 0x00000800 Platform Uncorrectable fatal + ================ =================================== + 0x00000001 Processor Correctable + 0x00000002 Processor Uncorrectable non-fatal + 0x00000004 Processor Uncorrectable fatal + 0x00000008 Memory Correctable + 0x00000010 Memory Uncorrectable non-fatal + 0x00000020 Memory Uncorrectable fatal + 0x00000040 PCI Express Correctable + 0x00000080 PCI Express Uncorrectable fatal + 0x00000100 PCI Express Uncorrectable non-fatal + 0x00000200 Platform Correctable + 0x00000400 Platform Uncorrectable non-fatal + 0x00000800 Platform Uncorrectable fatal + ================ =================================== The format of the file contents are as above, except present are only the available error types. @@ -73,9 +78,12 @@ The following files belong to it: injection. Value is a bitmask as specified in ACPI5.0 spec for the SET_ERROR_TYPE_WITH_ADDRESS data structure: - Bit 0 - Processor APIC field valid (see param3 below). - Bit 1 - Memory address and mask valid (param1 and param2). - Bit 2 - PCIe (seg,bus,dev,fn) valid (see param4 below). + Bit 0 + Processor APIC field valid (see param3 below). + Bit 1 + Memory address and mask valid (param1 and param2). + Bit 2 + PCIe (seg,bus,dev,fn) valid (see param4 below). If set to zero, legacy behavior is mimicked where the type of injection specifies just one bit set, and param1 is multiplexed. @@ -121,7 +129,7 @@ BIOS versions based on the ACPI 5.0 specification have more control over the target of the injection. For processor-related errors (type 0x1, 0x2 and 0x4), you can set flags to 0x3 (param3 for bit 0, and param1 and param2 for bit 1) so that you have more information added to the error -signature being injected. The actual data passed is this: +signature being injected. The actual data passed is this:: memory_address = param1; memory_address_range = param2; @@ -131,7 +139,7 @@ signature being injected. The actual data passed is this: For memory errors (type 0x8, 0x10 and 0x20) the address is set using param1 with a mask in param2 (0x0 is equivalent to all ones). For PCI express errors (type 0x40, 0x80 and 0x100) the segment, bus, device and -function are specified using param1: +function are specified using param1:: 31 24 23 16 15 11 10 8 7 0 +-------------------------------------------------+ @@ -152,26 +160,26 @@ documentation for details (and expect changes to this API if vendors creativity in using this feature expands beyond our expectations). -An error injection example: +An error injection example:: -# cd /sys/kernel/debug/apei/einj -# cat available_error_type # See which errors can be injected -0x00000002 Processor Uncorrectable non-fatal -0x00000008 Memory Correctable -0x00000010 Memory Uncorrectable non-fatal -# echo 0x12345000 > param1 # Set memory address for injection -# echo $((-1 << 12)) > param2 # Mask 0xfffffffffffff000 - anywhere in this page -# echo 0x8 > error_type # Choose correctable memory error -# echo 1 > error_inject # Inject now + # cd /sys/kernel/debug/apei/einj + # cat available_error_type # See which errors can be injected + 0x00000002 Processor Uncorrectable non-fatal + 0x00000008 Memory Correctable + 0x00000010 Memory Uncorrectable non-fatal + # echo 0x12345000 > param1 # Set memory address for injection + # echo $((-1 << 12)) > param2 # Mask 0xfffffffffffff000 - anywhere in this page + # echo 0x8 > error_type # Choose correctable memory error + # echo 1 > error_inject # Inject now -You should see something like this in dmesg: +You should see something like this in dmesg:: -[22715.830801] EDAC sbridge MC3: HANDLING MCE MEMORY ERROR -[22715.834759] EDAC sbridge MC3: CPU 0: Machine Check Event: 0 Bank 7: 8c00004000010090 -[22715.834759] EDAC sbridge MC3: TSC 0 -[22715.834759] EDAC sbridge MC3: ADDR 12345000 EDAC sbridge MC3: MISC 144780c86 -[22715.834759] EDAC sbridge MC3: PROCESSOR 0:306e7 TIME 1422553404 SOCKET 0 APIC 0 -[22716.616173] EDAC MC3: 1 CE memory read error on CPU_SrcID#0_Channel#0_DIMM#0 (channel:0 slot:0 page:0x12345 offset:0x0 grain:32 syndrome:0x0 - area:DRAM err_code:0001:0090 socket:0 channel_mask:1 rank:0) + [22715.830801] EDAC sbridge MC3: HANDLING MCE MEMORY ERROR + [22715.834759] EDAC sbridge MC3: CPU 0: Machine Check Event: 0 Bank 7: 8c00004000010090 + [22715.834759] EDAC sbridge MC3: TSC 0 + [22715.834759] EDAC sbridge MC3: ADDR 12345000 EDAC sbridge MC3: MISC 144780c86 + [22715.834759] EDAC sbridge MC3: PROCESSOR 0:306e7 TIME 1422553404 SOCKET 0 APIC 0 + [22716.616173] EDAC MC3: 1 CE memory read error on CPU_SrcID#0_Channel#0_DIMM#0 (channel:0 slot:0 page:0x12345 offset:0x0 grain:32 syndrome:0x0 - area:DRAM err_code:0001:0090 socket:0 channel_mask:1 rank:0) For more information about EINJ, please refer to ACPI specification version 4.0, section 17.5 and ACPI 5.0, section 18.6. diff --git a/Documentation/firmware-guide/acpi/apei/output_format.rst b/Documentation/firmware-guide/acpi/apei/output_format.rst new file mode 100644 index 000000000000..c2e7ebddb529 --- /dev/null +++ b/Documentation/firmware-guide/acpi/apei/output_format.rst @@ -0,0 +1,150 @@ +.. SPDX-License-Identifier: GPL-2.0 + +================== +APEI output format +================== + +APEI uses printk as hardware error reporting interface, the output +format is as follow:: + + <error record> := + APEI generic hardware error status + severity: <integer>, <severity string> + section: <integer>, severity: <integer>, <severity string> + flags: <integer> + <section flags strings> + fru_id: <uuid string> + fru_text: <string> + section_type: <section type string> + <section data> + + <severity string>* := recoverable | fatal | corrected | info + + <section flags strings># := + [primary][, containment warning][, reset][, threshold exceeded]\ + [, resource not accessible][, latent error] + + <section type string> := generic processor error | memory error | \ + PCIe error | unknown, <uuid string> + + <section data> := + <generic processor section data> | <memory section data> | \ + <pcie section data> | <null> + + <generic processor section data> := + [processor_type: <integer>, <proc type string>] + [processor_isa: <integer>, <proc isa string>] + [error_type: <integer> + <proc error type strings>] + [operation: <integer>, <proc operation string>] + [flags: <integer> + <proc flags strings>] + [level: <integer>] + [version_info: <integer>] + [processor_id: <integer>] + [target_address: <integer>] + [requestor_id: <integer>] + [responder_id: <integer>] + [IP: <integer>] + + <proc type string>* := IA32/X64 | IA64 + + <proc isa string>* := IA32 | IA64 | X64 + + <processor error type strings># := + [cache error][, TLB error][, bus error][, micro-architectural error] + + <proc operation string>* := unknown or generic | data read | data write | \ + instruction execution + + <proc flags strings># := + [restartable][, precise IP][, overflow][, corrected] + + <memory section data> := + [error_status: <integer>] + [physical_address: <integer>] + [physical_address_mask: <integer>] + [node: <integer>] + [card: <integer>] + [module: <integer>] + [bank: <integer>] + [device: <integer>] + [row: <integer>] + [column: <integer>] + [bit_position: <integer>] + [requestor_id: <integer>] + [responder_id: <integer>] + [target_id: <integer>] + [error_type: <integer>, <mem error type string>] + + <mem error type string>* := + unknown | no error | single-bit ECC | multi-bit ECC | \ + single-symbol chipkill ECC | multi-symbol chipkill ECC | master abort | \ + target abort | parity error | watchdog timeout | invalid address | \ + mirror Broken | memory sparing | scrub corrected error | \ + scrub uncorrected error + + <pcie section data> := + [port_type: <integer>, <pcie port type string>] + [version: <integer>.<integer>] + [command: <integer>, status: <integer>] + [device_id: <integer>:<integer>:<integer>.<integer> + slot: <integer> + secondary_bus: <integer> + vendor_id: <integer>, device_id: <integer> + class_code: <integer>] + [serial number: <integer>, <integer>] + [bridge: secondary_status: <integer>, control: <integer>] + [aer_status: <integer>, aer_mask: <integer> + <aer status string> + [aer_uncor_severity: <integer>] + aer_layer=<aer layer string>, aer_agent=<aer agent string> + aer_tlp_header: <integer> <integer> <integer> <integer>] + + <pcie port type string>* := PCIe end point | legacy PCI end point | \ + unknown | unknown | root port | upstream switch port | \ + downstream switch port | PCIe to PCI/PCI-X bridge | \ + PCI/PCI-X to PCIe bridge | root complex integrated endpoint device | \ + root complex event collector + + if section severity is fatal or recoverable + <aer status string># := + unknown | unknown | unknown | unknown | Data Link Protocol | \ + unknown | unknown | unknown | unknown | unknown | unknown | unknown | \ + Poisoned TLP | Flow Control Protocol | Completion Timeout | \ + Completer Abort | Unexpected Completion | Receiver Overflow | \ + Malformed TLP | ECRC | Unsupported Request + else + <aer status string># := + Receiver Error | unknown | unknown | unknown | unknown | unknown | \ + Bad TLP | Bad DLLP | RELAY_NUM Rollover | unknown | unknown | unknown | \ + Replay Timer Timeout | Advisory Non-Fatal + fi + + <aer layer string> := + Physical Layer | Data Link Layer | Transaction Layer + + <aer agent string> := + Receiver ID | Requester ID | Completer ID | Transmitter ID + +Where, [] designate corresponding content is optional + +All <field string> description with * has the following format:: + + field: <integer>, <field string> + +Where value of <integer> should be the position of "string" in <field +string> description. Otherwise, <field string> will be "unknown". + +All <field strings> description with # has the following format:: + + field: <integer> + <field strings> + +Where each string in <fields strings> corresponding to one set bit of +<integer>. The bit position is the position of "string" in <field +strings> description. + +For more detailed explanation of every field, please refer to UEFI +specification version 2.3 or later, section Appendix N: Common +Platform Error Record. diff --git a/Documentation/acpi/debug.txt b/Documentation/firmware-guide/acpi/debug.rst index 65bf47c46b6d..1a152dd1d765 100644 --- a/Documentation/acpi/debug.txt +++ b/Documentation/firmware-guide/acpi/debug.rst @@ -1,18 +1,21 @@ - ACPI Debug Output +.. SPDX-License-Identifier: GPL-2.0 +================= +ACPI Debug Output +================= The ACPI CA, the Linux ACPI core, and some ACPI drivers can generate debug output. This document describes how to use this facility. Compile-time configuration --------------------------- +========================== ACPI debug output is globally enabled by CONFIG_ACPI_DEBUG. If this config option is turned off, the debug messages are not even built into the kernel. Boot- and run-time configuration --------------------------------- +================================ When CONFIG_ACPI_DEBUG=y, you can select the component and level of messages you're interested in. At boot-time, use the acpi.debug_layer and @@ -21,7 +24,7 @@ debug_layer and debug_level files in /sys/module/acpi/parameters/ to control the debug messages. debug_layer (component) ------------------------ +======================= The "debug_layer" is a mask that selects components of interest, e.g., a specific driver or part of the ACPI interpreter. To build the debug_layer @@ -33,7 +36,7 @@ to /sys/module/acpi/parameters/debug_layer. The possible components are defined in include/acpi/acoutput.h and include/acpi/acpi_drivers.h. Reading /sys/module/acpi/parameters/debug_layer -shows the supported mask values, currently these: +shows the supported mask values, currently these:: ACPI_UTILITIES 0x00000001 ACPI_HARDWARE 0x00000002 @@ -65,7 +68,7 @@ shows the supported mask values, currently these: ACPI_PROCESSOR_COMPONENT 0x20000000 debug_level ------------ +=========== The "debug_level" is a mask that selects different types of messages, e.g., those related to initialization, method execution, informational messages, etc. @@ -81,7 +84,7 @@ to /sys/module/acpi/parameters/debug_level. The possible levels are defined in include/acpi/acoutput.h. Reading /sys/module/acpi/parameters/debug_level shows the supported mask values, -currently these: +currently these:: ACPI_LV_INIT 0x00000001 ACPI_LV_DEBUG_OBJECT 0x00000002 @@ -113,9 +116,9 @@ currently these: ACPI_LV_EVENTS 0x80000000 Examples --------- +======== -For example, drivers/acpi/bus.c contains this: +For example, drivers/acpi/bus.c contains this:: #define _COMPONENT ACPI_BUS_COMPONENT ... @@ -127,22 +130,22 @@ statement uses ACPI_DB_INFO, which is macro based on the ACPI_LV_INFO definition.) Enable all AML "Debug" output (stores to the Debug object while interpreting -AML) during boot: +AML) during boot:: acpi.debug_layer=0xffffffff acpi.debug_level=0x2 -Enable PCI and PCI interrupt routing debug messages: +Enable PCI and PCI interrupt routing debug messages:: acpi.debug_layer=0x400000 acpi.debug_level=0x4 -Enable all ACPI hardware-related messages: +Enable all ACPI hardware-related messages:: acpi.debug_layer=0x2 acpi.debug_level=0xffffffff -Enable all ACPI_DB_INFO messages after boot: +Enable all ACPI_DB_INFO messages after boot:: # echo 0x4 > /sys/module/acpi/parameters/debug_level -Show all valid component values: +Show all valid component values:: # cat /sys/module/acpi/parameters/debug_layer diff --git a/Documentation/acpi/dsd/data-node-references.txt b/Documentation/firmware-guide/acpi/dsd/data-node-references.rst index c3871565c8cf..1351984e767c 100644 --- a/Documentation/acpi/dsd/data-node-references.txt +++ b/Documentation/firmware-guide/acpi/dsd/data-node-references.rst @@ -1,9 +1,12 @@ -Copyright (C) 2018 Intel Corporation -Author: Sakari Ailus <sakari.ailus@linux.intel.com> - +.. SPDX-License-Identifier: GPL-2.0 +.. include:: <isonum.txt> +=================================== Referencing hierarchical data nodes ------------------------------------ +=================================== + +:Copyright: |copy| 2018 Intel Corporation +:Author: Sakari Ailus <sakari.ailus@linux.intel.com> ACPI in general allows referring to device objects in the tree only. Hierarchical data extension nodes may not be referred to directly, hence this @@ -28,13 +31,14 @@ extension key. Example -------- +======= - In the ASL snippet below, the "reference" _DSD property [2] contains a - device object reference to DEV0 and under that device object, a - hierarchical data extension key "node@1" referring to the NOD1 object - and lastly, a hierarchical data extension key "anothernode" referring to - the ANOD object which is also the final target node of the reference. +In the ASL snippet below, the "reference" _DSD property [2] contains a +device object reference to DEV0 and under that device object, a +hierarchical data extension key "node@1" referring to the NOD1 object +and lastly, a hierarchical data extension key "anothernode" referring to +the ANOD object which is also the final target node of the reference. +:: Device (DEV0) { @@ -75,15 +79,15 @@ Example }) } -Please also see a graph example in graph.txt . +Please also see a graph example in :doc:`graph`. References ----------- +========== [1] Hierarchical Data Extension UUID For _DSD. - <URL:http://www.uefi.org/sites/default/files/resources/_DSD-hierarchical-data-extension-UUID-v1.1.pdf>, - referenced 2018-07-17. +<http://www.uefi.org/sites/default/files/resources/_DSD-hierarchical-data-extension-UUID-v1.1.pdf>, +referenced 2018-07-17. [2] Device Properties UUID For _DSD. - <URL:http://www.uefi.org/sites/default/files/resources/_DSD-device-properties-UUID.pdf>, - referenced 2016-10-04. +<http://www.uefi.org/sites/default/files/resources/_DSD-device-properties-UUID.pdf>, +referenced 2016-10-04. diff --git a/Documentation/acpi/dsd/graph.txt b/Documentation/firmware-guide/acpi/dsd/graph.rst index b9ce910781dc..e0baed35b037 100644 --- a/Documentation/acpi/dsd/graph.txt +++ b/Documentation/firmware-guide/acpi/dsd/graph.rst @@ -1,8 +1,11 @@ -Graphs +.. SPDX-License-Identifier: GPL-2.0 +====== +Graphs +====== _DSD ----- +==== _DSD (Device Specific Data) [7] is a predefined ACPI device configuration object that can be used to convey information on @@ -30,7 +33,7 @@ hierarchical data extension array on each depth. Ports and endpoints -------------------- +=================== The port and endpoint concepts are very similar to those in Devicetree [3]. A port represents an interface in a device, and an endpoint @@ -38,9 +41,9 @@ represents a connection to that interface. All port nodes are located under the device's "_DSD" node in the hierarchical data extension tree. The data extension related to each port node must begin -with "port" and must be followed by the "@" character and the number of the port -as its key. The target object it refers to should be called "PRTX", where "X" is -the number of the port. An example of such a package would be: +with "port" and must be followed by the "@" character and the number of the +port as its key. The target object it refers to should be called "PRTX", where +"X" is the number of the port. An example of such a package would be:: Package() { "port@4", PRT4 } @@ -49,7 +52,7 @@ data extension key of the endpoint nodes must begin with "endpoint" and must be followed by the "@" character and the number of the endpoint. The object it refers to should be called "EPXY", where "X" is the number of the port and "Y" is the number of the endpoint. An example of such a -package would be: +package would be:: Package() { "endpoint@0", EP40 } @@ -62,85 +65,85 @@ of that port shall be zero. Similarly, if a port may only have a single endpoint, the number of that endpoint shall be zero. The endpoint reference uses property extension with "remote-endpoint" property -name followed by a reference in the same package. Such references consist of the +name followed by a reference in the same package. Such references consist of the remote device reference, the first package entry of the port data extension reference under the device and finally the first package entry of the endpoint -data extension reference under the port. Individual references thus appear as: +data extension reference under the port. Individual references thus appear as:: Package() { device, "port@X", "endpoint@Y" } -In the above example, "X" is the number of the port and "Y" is the number of the -endpoint. +In the above example, "X" is the number of the port and "Y" is the number of +the endpoint. The references to endpoints must be always done both ways, to the remote endpoint and back from the referred remote endpoint node. -A simple example of this is show below: +A simple example of this is show below:: Scope (\_SB.PCI0.I2C2) { - Device (CAM0) - { - Name (_DSD, Package () { - ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), - Package () { - Package () { "compatible", Package () { "nokia,smia" } }, - }, - ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b"), - Package () { - Package () { "port@0", PRT0 }, - } - }) - Name (PRT0, Package() { - ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), - Package () { - Package () { "reg", 0 }, - }, - ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b"), - Package () { - Package () { "endpoint@0", EP00 }, - } - }) - Name (EP00, Package() { - ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), - Package () { - Package () { "reg", 0 }, - Package () { "remote-endpoint", Package() { \_SB.PCI0.ISP, "port@4", "endpoint@0" } }, - } - }) - } + Device (CAM0) + { + Name (_DSD, Package () { + ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), + Package () { + Package () { "compatible", Package () { "nokia,smia" } }, + }, + ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b"), + Package () { + Package () { "port@0", PRT0 }, + } + }) + Name (PRT0, Package() { + ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), + Package () { + Package () { "reg", 0 }, + }, + ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b"), + Package () { + Package () { "endpoint@0", EP00 }, + } + }) + Name (EP00, Package() { + ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), + Package () { + Package () { "reg", 0 }, + Package () { "remote-endpoint", Package() { \_SB.PCI0.ISP, "port@4", "endpoint@0" } }, + } + }) + } } Scope (\_SB.PCI0) { - Device (ISP) - { - Name (_DSD, Package () { - ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b"), - Package () { - Package () { "port@4", PRT4 }, - } - }) - - Name (PRT4, Package() { - ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), - Package () { - Package () { "reg", 4 }, /* CSI-2 port number */ - }, - ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b"), - Package () { - Package () { "endpoint@0", EP40 }, - } - }) - - Name (EP40, Package() { - ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), - Package () { - Package () { "reg", 0 }, - Package () { "remote-endpoint", Package () { \_SB.PCI0.I2C2.CAM0, "port@0", "endpoint@0" } }, - } - }) - } + Device (ISP) + { + Name (_DSD, Package () { + ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b"), + Package () { + Package () { "port@4", PRT4 }, + } + }) + + Name (PRT4, Package() { + ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), + Package () { + Package () { "reg", 4 }, /* CSI-2 port number */ + }, + ToUUID("dbb8e3e6-5886-4ba6-8795-1319f52a966b"), + Package () { + Package () { "endpoint@0", EP40 }, + } + }) + + Name (EP40, Package() { + ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), + Package () { + Package () { "reg", 0 }, + Package () { "remote-endpoint", Package () { \_SB.PCI0.I2C2.CAM0, "port@0", "endpoint@0" } }, + } + }) + } } Here, the port 0 of the "CAM0" device is connected to the port 4 of @@ -148,27 +151,27 @@ the "ISP" device and vice versa. References ----------- +========== [1] _DSD (Device Specific Data) Implementation Guide. - <URL:http://www.uefi.org/sites/default/files/resources/_DSD-implementation-guide-toplevel-1_1.htm>, + http://www.uefi.org/sites/default/files/resources/_DSD-implementation-guide-toplevel-1_1.htm, referenced 2016-10-03. -[2] Devicetree. <URL:http://www.devicetree.org>, referenced 2016-10-03. +[2] Devicetree. http://www.devicetree.org, referenced 2016-10-03. [3] Documentation/devicetree/bindings/graph.txt [4] Device Properties UUID For _DSD. - <URL:http://www.uefi.org/sites/default/files/resources/_DSD-device-properties-UUID.pdf>, + http://www.uefi.org/sites/default/files/resources/_DSD-device-properties-UUID.pdf, referenced 2016-10-04. [5] Hierarchical Data Extension UUID For _DSD. - <URL:http://www.uefi.org/sites/default/files/resources/_DSD-hierarchical-data-extension-UUID-v1.1.pdf>, + http://www.uefi.org/sites/default/files/resources/_DSD-hierarchical-data-extension-UUID-v1.1.pdf, referenced 2016-10-04. [6] Advanced Configuration and Power Interface Specification. - <URL:http://www.uefi.org/sites/default/files/resources/ACPI_6_1.pdf>, + http://www.uefi.org/sites/default/files/resources/ACPI_6_1.pdf, referenced 2016-10-04. [7] _DSD Device Properties Usage Rules. - Documentation/acpi/DSD-properties-rules.txt + :doc:`../DSD-properties-rules` diff --git a/Documentation/acpi/enumeration.txt b/Documentation/firmware-guide/acpi/enumeration.rst index 7bcf9c3d9fbe..6b32b7be8c85 100644 --- a/Documentation/acpi/enumeration.txt +++ b/Documentation/firmware-guide/acpi/enumeration.rst @@ -1,5 +1,9 @@ -ACPI based device enumeration -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +.. SPDX-License-Identifier: GPL-2.0 + +============================= +ACPI Based Device Enumeration +============================= + ACPI 5 introduced a set of new resources (UartTSerialBus, I2cSerialBus, SpiSerialBus, GpioIo and GpioInt) which can be used in enumerating slave devices behind serial bus controllers. @@ -11,12 +15,12 @@ that are accessed through memory-mapped registers. In order to support this and re-use the existing drivers as much as possible we decided to do following: - o Devices that have no bus connector resource are represented as - platform devices. + - Devices that have no bus connector resource are represented as + platform devices. - o Devices behind real busses where there is a connector resource - are represented as struct spi_device or struct i2c_device - (standard UARTs are not busses so there is no struct uart_device). + - Devices behind real busses where there is a connector resource + are represented as struct spi_device or struct i2c_device + (standard UARTs are not busses so there is no struct uart_device). As both ACPI and Device Tree represent a tree of devices (and their resources) this implementation follows the Device Tree way as much as @@ -31,7 +35,8 @@ enumerated from ACPI namespace. This handle can be used to extract other device-specific configuration. There is an example of this below. Platform bus support -~~~~~~~~~~~~~~~~~~~~ +==================== + Since we are using platform devices to represent devices that are not connected to any physical bus we only need to implement a platform driver for the device and add supported ACPI IDs. If this same IP-block is used on @@ -39,7 +44,7 @@ some other non-ACPI platform, the driver might work out of the box or needs some minor changes. Adding ACPI support for an existing driver should be pretty -straightforward. Here is the simplest example: +straightforward. Here is the simplest example:: #ifdef CONFIG_ACPI static const struct acpi_device_id mydrv_acpi_match[] = { @@ -61,12 +66,13 @@ configuring GPIOs it can get its ACPI handle and extract this information from ACPI tables. DMA support -~~~~~~~~~~~ +=========== + DMA controllers enumerated via ACPI should be registered in the system to provide generic access to their resources. For example, a driver that would like to be accessible to slave devices via generic API call dma_request_slave_channel() must register itself at the end of the probe -function like this: +function like this:: err = devm_acpi_dma_controller_register(dev, xlate_func, dw); /* Handle the error if it's not a case of !CONFIG_ACPI */ @@ -74,7 +80,7 @@ function like this: and implement custom xlate function if needed (usually acpi_dma_simple_xlate() is enough) which converts the FixedDMA resource provided by struct acpi_dma_spec into the corresponding DMA channel. A piece of code for that case -could look like: +could look like:: #ifdef CONFIG_ACPI struct filter_args { @@ -114,7 +120,7 @@ provided by struct acpi_dma. Clients must call dma_request_slave_channel() with the string parameter that corresponds to a specific FixedDMA resource. By default "tx" means the first entry of the FixedDMA resource array, "rx" means the second entry. The table -below shows a layout: +below shows a layout:: Device (I2C0) { @@ -138,12 +144,13 @@ acpi_dma_request_slave_chan_by_index() directly and therefore choose the specific FixedDMA resource by its index. SPI serial bus support -~~~~~~~~~~~~~~~~~~~~~~ +====================== + Slave devices behind SPI bus have SpiSerialBus resource attached to them. This is extracted automatically by the SPI core and the slave devices are enumerated once spi_register_master() is called by the bus driver. -Here is what the ACPI namespace for a SPI slave might look like: +Here is what the ACPI namespace for a SPI slave might look like:: Device (EEP0) { @@ -163,7 +170,7 @@ Here is what the ACPI namespace for a SPI slave might look like: The SPI device drivers only need to add ACPI IDs in a similar way than with the platform device drivers. Below is an example where we add ACPI support -to at25 SPI eeprom driver (this is meant for the above ACPI snippet): +to at25 SPI eeprom driver (this is meant for the above ACPI snippet):: #ifdef CONFIG_ACPI static const struct acpi_device_id at25_acpi_match[] = { @@ -182,7 +189,7 @@ to at25 SPI eeprom driver (this is meant for the above ACPI snippet): Note that this driver actually needs more information like page size of the eeprom etc. but at the time writing this there is no standard way of -passing those. One idea is to return this in _DSM method like: +passing those. One idea is to return this in _DSM method like:: Device (EEP0) { @@ -202,7 +209,7 @@ passing those. One idea is to return this in _DSM method like: } Then the at25 SPI driver can get this configuration by calling _DSM on its -ACPI handle like: +ACPI handle like:: struct acpi_buffer output = { ACPI_ALLOCATE_BUFFER, NULL }; struct acpi_object_list input; @@ -220,14 +227,15 @@ ACPI handle like: kfree(output.pointer); I2C serial bus support -~~~~~~~~~~~~~~~~~~~~~~ +====================== + The slaves behind I2C bus controller only need to add the ACPI IDs like with the platform and SPI drivers. The I2C core automatically enumerates any slave devices behind the controller device once the adapter is registered. Below is an example of how to add ACPI support to the existing mpu3050 -input driver: +input driver:: #ifdef CONFIG_ACPI static const struct acpi_device_id mpu3050_acpi_match[] = { @@ -251,56 +259,57 @@ input driver: }; GPIO support -~~~~~~~~~~~~ +============ + ACPI 5 introduced two new resources to describe GPIO connections: GpioIo and GpioInt. These resources can be used to pass GPIO numbers used by the device to the driver. ACPI 5.1 extended this with _DSD (Device Specific Data) which made it possible to name the GPIOs among other things. -For example: +For example:: -Device (DEV) -{ - Method (_CRS, 0, NotSerialized) + Device (DEV) { - Name (SBUF, ResourceTemplate() + Method (_CRS, 0, NotSerialized) { - ... - // Used to power on/off the device - GpioIo (Exclusive, PullDefault, 0x0000, 0x0000, - IoRestrictionOutputOnly, "\\_SB.PCI0.GPI0", - 0x00, ResourceConsumer,,) + Name (SBUF, ResourceTemplate() { - // Pin List - 0x0055 - } + ... + // Used to power on/off the device + GpioIo (Exclusive, PullDefault, 0x0000, 0x0000, + IoRestrictionOutputOnly, "\\_SB.PCI0.GPI0", + 0x00, ResourceConsumer,,) + { + // Pin List + 0x0055 + } + + // Interrupt for the device + GpioInt (Edge, ActiveHigh, ExclusiveAndWake, PullNone, + 0x0000, "\\_SB.PCI0.GPI0", 0x00, ResourceConsumer,,) + { + // Pin list + 0x0058 + } + + ... - // Interrupt for the device - GpioInt (Edge, ActiveHigh, ExclusiveAndWake, PullNone, - 0x0000, "\\_SB.PCI0.GPI0", 0x00, ResourceConsumer,,) - { - // Pin list - 0x0058 } - ... - + Return (SBUF) } - Return (SBUF) - } - - // ACPI 5.1 _DSD used for naming the GPIOs - Name (_DSD, Package () - { - ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), - Package () + // ACPI 5.1 _DSD used for naming the GPIOs + Name (_DSD, Package () { - Package () {"power-gpios", Package() {^DEV, 0, 0, 0 }}, - Package () {"irq-gpios", Package() {^DEV, 1, 0, 0 }}, - } - }) - ... + ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), + Package () + { + Package () {"power-gpios", Package() {^DEV, 0, 0, 0 }}, + Package () {"irq-gpios", Package() {^DEV, 1, 0, 0 }}, + } + }) + ... These GPIO numbers are controller relative and path "\\_SB.PCI0.GPI0" specifies the path to the controller. In order to use these GPIOs in Linux @@ -310,7 +319,7 @@ There is a standard GPIO API for that and is documented in Documentation/gpio/. In the above example we can get the corresponding two GPIO descriptors with -a code like this: +a code like this:: #include <linux/gpio/consumer.h> ... @@ -334,21 +343,22 @@ See Documentation/acpi/gpio-properties.txt for more information about the _DSD binding related to GPIOs. MFD devices -~~~~~~~~~~~ +=========== + The MFD devices register their children as platform devices. For the child devices there needs to be an ACPI handle that they can use to reference parts of the ACPI namespace that relate to them. In the Linux MFD subsystem we provide two ways: - o The children share the parent ACPI handle. - o The MFD cell can specify the ACPI id of the device. + - The children share the parent ACPI handle. + - The MFD cell can specify the ACPI id of the device. For the first case, the MFD drivers do not need to do anything. The resulting child platform device will have its ACPI_COMPANION() set to point to the parent device. If the ACPI namespace has a device that we can match using an ACPI id or ACPI -adr, the cell should be set like: +adr, the cell should be set like:: static struct mfd_cell_acpi_match my_subdevice_cell_acpi_match = { .pnpid = "XYZ0001", @@ -366,7 +376,8 @@ the MFD device and if found, that ACPI companion device is bound to the resulting child platform device. Device Tree namespace link device ID -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +==================================== + The Device Tree protocol uses device identification based on the "compatible" property whose value is a string or an array of strings recognized as device identifiers by drivers and the driver core. The set of all those strings may be @@ -410,6 +421,32 @@ Specifically, the device IDs returned by _HID and preceding PRP0001 in the _CID return package will be checked first. Also in that case the bus type the device will be enumerated to depends on the device ID returned by _HID. +For example, the following ACPI sample might be used to enumerate an lm75-type +I2C temperature sensor and match it to the driver using the Device Tree +namespace link: + + Device (TMP0) + { + Name (_HID, "PRP0001") + Name (_DSD, Package() { + ToUUID("daffd814-6eba-4d8c-8a91-bc9bbf4aa301"), + Package () { + Package (2) { "compatible", "ti,tmp75" }, + } + }) + Method (_CRS, 0, Serialized) + { + Name (SBUF, ResourceTemplate () + { + I2cSerialBusV2 (0x48, ControllerInitiated, + 400000, AddressingMode7Bit, + "\\_SB.PCI0.I2C1", 0x00, + ResourceConsumer, , Exclusive,) + }) + Return (SBUF) + } + } + It is valid to define device objects with a _HID returning PRP0001 and without the "compatible" property in the _DSD or a _CID as long as one of their ancestors provides a _DSD with a valid "compatible" property. Such device @@ -423,4 +460,4 @@ the _DSD of the device object itself or the _DSD of its ancestor in the Otherwise, the _DSD itself is regarded as invalid and therefore the "compatible" property returned by it is meaningless. -Refer to DSD-properties-rules.txt for more information. +Refer to :doc:`DSD-properties-rules` for more information. diff --git a/Documentation/acpi/gpio-properties.txt b/Documentation/firmware-guide/acpi/gpio-properties.rst index 88c65cb5bf0a..bb6d74f23ee0 100644 --- a/Documentation/acpi/gpio-properties.txt +++ b/Documentation/firmware-guide/acpi/gpio-properties.rst @@ -1,5 +1,8 @@ +.. SPDX-License-Identifier: GPL-2.0 + +====================================== _DSD Device Properties Related to GPIO --------------------------------------- +====================================== With the release of ACPI 5.1, the _DSD configuration object finally allows names to be given to GPIOs (and other things as well) returned @@ -8,7 +11,7 @@ the corresponding GPIO, which is pretty error prone (it depends on the _CRS output ordering, for example). With _DSD we can now query GPIOs using a name instead of an integer -index, like the ASL example below shows: +index, like the ASL example below shows:: // Bluetooth device with reset and shutdown GPIOs Device (BTH) @@ -34,15 +37,19 @@ index, like the ASL example below shows: }) } -The format of the supported GPIO property is: +The format of the supported GPIO property is:: Package () { "name", Package () { ref, index, pin, active_low }} - ref - The device that has _CRS containing GpioIo()/GpioInt() resources, - typically this is the device itself (BTH in our case). - index - Index of the GpioIo()/GpioInt() resource in _CRS starting from zero. - pin - Pin in the GpioIo()/GpioInt() resource. Typically this is zero. - active_low - If 1 the GPIO is marked as active_low. +ref + The device that has _CRS containing GpioIo()/GpioInt() resources, + typically this is the device itself (BTH in our case). +index + Index of the GpioIo()/GpioInt() resource in _CRS starting from zero. +pin + Pin in the GpioIo()/GpioInt() resource. Typically this is zero. +active_low + If 1 the GPIO is marked as active_low. Since ACPI GpioIo() resource does not have a field saying whether it is active low or high, the "active_low" argument can be used here. Setting @@ -55,7 +62,7 @@ It is possible to leave holes in the array of GPIOs. This is useful in cases like with SPI host controllers where some chip selects may be implemented as GPIOs and some as native signals. For example a SPI host controller can have chip selects 0 and 2 implemented as GPIOs and 1 as -native: +native:: Package () { "cs-gpios", @@ -67,7 +74,7 @@ native: } Other supported properties --------------------------- +========================== Following Device Tree compatible device properties are also supported by _DSD device properties for GPIO controllers: @@ -78,7 +85,7 @@ _DSD device properties for GPIO controllers: - input - line-name -Example: +Example:: Name (_DSD, Package () { // _DSD Hierarchical Properties Extension UUID @@ -100,7 +107,7 @@ Example: - gpio-line-names -Example: +Example:: Package () { "gpio-line-names", @@ -114,7 +121,7 @@ See Documentation/devicetree/bindings/gpio/gpio.txt for more information about these properties. ACPI GPIO Mappings Provided by Drivers --------------------------------------- +====================================== There are systems in which the ACPI tables do not contain _DSD but provide _CRS with GpioIo()/GpioInt() resources and device drivers still need to work with @@ -139,16 +146,16 @@ line in that resource starting from zero, and the active-low flag for that line, respectively, in analogy with the _DSD GPIO property format specified above. For the example Bluetooth device discussed previously the data structures in -question would look like this: +question would look like this:: -static const struct acpi_gpio_params reset_gpio = { 1, 1, false }; -static const struct acpi_gpio_params shutdown_gpio = { 0, 0, false }; + static const struct acpi_gpio_params reset_gpio = { 1, 1, false }; + static const struct acpi_gpio_params shutdown_gpio = { 0, 0, false }; -static const struct acpi_gpio_mapping bluetooth_acpi_gpios[] = { - { "reset-gpios", &reset_gpio, 1 }, - { "shutdown-gpios", &shutdown_gpio, 1 }, - { }, -}; + static const struct acpi_gpio_mapping bluetooth_acpi_gpios[] = { + { "reset-gpios", &reset_gpio, 1 }, + { "shutdown-gpios", &shutdown_gpio, 1 }, + { }, + }; Next, the mapping table needs to be passed as the second argument to acpi_dev_add_driver_gpios() that will register it with the ACPI device object @@ -158,12 +165,12 @@ calling acpi_dev_remove_driver_gpios() on the ACPI device object where that table was previously registered. Using the _CRS fallback ------------------------ +======================= If a device does not have _DSD or the driver does not create ACPI GPIO mapping, the Linux GPIO framework refuses to return any GPIOs. This is because the driver does not know what it actually gets. For example if we -have a device like below: +have a device like below:: Device (BTH) { @@ -177,7 +184,7 @@ have a device like below: }) } -The driver might expect to get the right GPIO when it does: +The driver might expect to get the right GPIO when it does:: desc = gpiod_get(dev, "reset", GPIOD_OUT_LOW); @@ -193,22 +200,25 @@ the ACPI GPIO mapping tables are hardly linked to ACPI ID and certain objects, as listed in the above chapter, of the device in question. Getting GPIO descriptor ------------------------ +======================= + +There are two main approaches to get GPIO resource from ACPI:: -There are two main approaches to get GPIO resource from ACPI: - desc = gpiod_get(dev, connection_id, flags); - desc = gpiod_get_index(dev, connection_id, index, flags); + desc = gpiod_get(dev, connection_id, flags); + desc = gpiod_get_index(dev, connection_id, index, flags); We may consider two different cases here, i.e. when connection ID is provided and otherwise. -Case 1: - desc = gpiod_get(dev, "non-null-connection-id", flags); - desc = gpiod_get_index(dev, "non-null-connection-id", index, flags); +Case 1:: + + desc = gpiod_get(dev, "non-null-connection-id", flags); + desc = gpiod_get_index(dev, "non-null-connection-id", index, flags); + +Case 2:: -Case 2: - desc = gpiod_get(dev, NULL, flags); - desc = gpiod_get_index(dev, NULL, index, flags); + desc = gpiod_get(dev, NULL, flags); + desc = gpiod_get_index(dev, NULL, index, flags); Case 1 assumes that corresponding ACPI device description must have defined device properties and will prevent to getting any GPIO resources diff --git a/Documentation/firmware-guide/acpi/i2c-muxes.rst b/Documentation/firmware-guide/acpi/i2c-muxes.rst new file mode 100644 index 000000000000..3a8997ccd7c4 --- /dev/null +++ b/Documentation/firmware-guide/acpi/i2c-muxes.rst @@ -0,0 +1,61 @@ +.. SPDX-License-Identifier: GPL-2.0 + +============== +ACPI I2C Muxes +============== + +Describing an I2C device hierarchy that includes I2C muxes requires an ACPI +Device () scope per mux channel. + +Consider this topology:: + + +------+ +------+ + | SMB1 |-->| MUX0 |--CH00--> i2c client A (0x50) + | | | 0x70 |--CH01--> i2c client B (0x50) + +------+ +------+ + +which corresponds to the following ASL:: + + Device (SMB1) + { + Name (_HID, ...) + Device (MUX0) + { + Name (_HID, ...) + Name (_CRS, ResourceTemplate () { + I2cSerialBus (0x70, ControllerInitiated, I2C_SPEED, + AddressingMode7Bit, "^SMB1", 0x00, + ResourceConsumer,,) + } + + Device (CH00) + { + Name (_ADR, 0) + + Device (CLIA) + { + Name (_HID, ...) + Name (_CRS, ResourceTemplate () { + I2cSerialBus (0x50, ControllerInitiated, I2C_SPEED, + AddressingMode7Bit, "^CH00", 0x00, + ResourceConsumer,,) + } + } + } + + Device (CH01) + { + Name (_ADR, 1) + + Device (CLIB) + { + Name (_HID, ...) + Name (_CRS, ResourceTemplate () { + I2cSerialBus (0x50, ControllerInitiated, I2C_SPEED, + AddressingMode7Bit, "^CH01", 0x00, + ResourceConsumer,,) + } + } + } + } + } diff --git a/Documentation/firmware-guide/acpi/index.rst b/Documentation/firmware-guide/acpi/index.rst new file mode 100644 index 000000000000..ae609eec4679 --- /dev/null +++ b/Documentation/firmware-guide/acpi/index.rst @@ -0,0 +1,26 @@ +.. SPDX-License-Identifier: GPL-2.0 + +============ +ACPI Support +============ + +.. toctree:: + :maxdepth: 1 + + namespace + dsd/graph + dsd/data-node-references + enumeration + osi + method-customizing + method-tracing + DSD-properties-rules + debug + aml-debugger + apei/output_format + apei/einj + gpio-properties + i2c-muxes + acpi-lid + lpit + video_extension diff --git a/Documentation/acpi/lpit.txt b/Documentation/firmware-guide/acpi/lpit.rst index b426398d2e97..aca928fab027 100644 --- a/Documentation/acpi/lpit.txt +++ b/Documentation/firmware-guide/acpi/lpit.rst @@ -1,3 +1,9 @@ +.. SPDX-License-Identifier: GPL-2.0 + +=========================== +Low Power Idle Table (LPIT) +=========================== + To enumerate platform Low Power Idle states, Intel platforms are using “Low Power Idle Table” (LPIT). More details about this table can be downloaded from: @@ -8,13 +14,15 @@ Residencies for each low power state can be read via FFH On platforms supporting S0ix sleep states, there can be two types of residencies: -- CPU PKG C10 (Read via FFH interface) -- Platform Controller Hub (PCH) SLP_S0 (Read via memory mapped interface) + + - CPU PKG C10 (Read via FFH interface) + - Platform Controller Hub (PCH) SLP_S0 (Read via memory mapped interface) The following attributes are added dynamically to the cpuidle -sysfs attribute group: - /sys/devices/system/cpu/cpuidle/low_power_idle_cpu_residency_us - /sys/devices/system/cpu/cpuidle/low_power_idle_system_residency_us +sysfs attribute group:: + + /sys/devices/system/cpu/cpuidle/low_power_idle_cpu_residency_us + /sys/devices/system/cpu/cpuidle/low_power_idle_system_residency_us The "low_power_idle_cpu_residency_us" attribute shows time spent by the CPU package in PKG C10 diff --git a/Documentation/firmware-guide/acpi/method-customizing.rst b/Documentation/firmware-guide/acpi/method-customizing.rst new file mode 100644 index 000000000000..de3ebcaed4cf --- /dev/null +++ b/Documentation/firmware-guide/acpi/method-customizing.rst @@ -0,0 +1,89 @@ +.. SPDX-License-Identifier: GPL-2.0 + +======================================= +Linux ACPI Custom Control Method How To +======================================= + +:Author: Zhang Rui <rui.zhang@intel.com> + + +Linux supports customizing ACPI control methods at runtime. + +Users can use this to: + +1. override an existing method which may not work correctly, + or just for debugging purposes. +2. insert a completely new method in order to create a missing + method such as _OFF, _ON, _STA, _INI, etc. + +For these cases, it is far simpler to dynamically install a single +control method rather than override the entire DSDT, because kernel +rebuild/reboot is not needed and test result can be got in minutes. + +.. note:: + + - Only ACPI METHOD can be overridden, any other object types like + "Device", "OperationRegion", are not recognized. Methods + declared inside scope operators are also not supported. + + - The same ACPI control method can be overridden for many times, + and it's always the latest one that used by Linux/kernel. + + - To get the ACPI debug object output (Store (AAAA, Debug)), + please run:: + + echo 1 > /sys/module/acpi/parameters/aml_debug_output + + +1. override an existing method +============================== +a) get the ACPI table via ACPI sysfs I/F. e.g. to get the DSDT, + just run "cat /sys/firmware/acpi/tables/DSDT > /tmp/dsdt.dat" +b) disassemble the table by running "iasl -d dsdt.dat". +c) rewrite the ASL code of the method and save it in a new file, +d) package the new file (psr.asl) to an ACPI table format. + Here is an example of a customized \_SB._AC._PSR method:: + + DefinitionBlock ("", "SSDT", 1, "", "", 0x20080715) + { + Method (\_SB_.AC._PSR, 0, NotSerialized) + { + Store ("In AC _PSR", Debug) + Return (ACON) + } + } + + Note that the full pathname of the method in ACPI namespace + should be used. +e) assemble the file to generate the AML code of the method. + e.g. "iasl -vw 6084 psr.asl" (psr.aml is generated as a result) + If parameter "-vw 6084" is not supported by your iASL compiler, + please try a newer version. +f) mount debugfs by "mount -t debugfs none /sys/kernel/debug" +g) override the old method via the debugfs by running + "cat /tmp/psr.aml > /sys/kernel/debug/acpi/custom_method" + +2. insert a new method +====================== +This is easier than overriding an existing method. +We just need to create the ASL code of the method we want to +insert and then follow the step c) ~ g) in section 1. + +3. undo your changes +==================== +The "undo" operation is not supported for a new inserted method +right now, i.e. we can not remove a method currently. +For an overridden method, in order to undo your changes, please +save a copy of the method original ASL code in step c) section 1, +and redo step c) ~ g) to override the method with the original one. + + +.. note:: We can use a kernel with multiple custom ACPI method running, + But each individual write to debugfs can implement a SINGLE + method override. i.e. if we want to insert/override multiple + ACPI methods, we need to redo step c) ~ g) for multiple times. + +.. note:: Be aware that root can mis-use this driver to modify arbitrary + memory and gain additional rights, if root's privileges got + restricted (for example if root is not allowed to load additional + modules after boot). diff --git a/Documentation/firmware-guide/acpi/method-tracing.rst b/Documentation/firmware-guide/acpi/method-tracing.rst new file mode 100644 index 000000000000..d0b077b73f5f --- /dev/null +++ b/Documentation/firmware-guide/acpi/method-tracing.rst @@ -0,0 +1,238 @@ +.. SPDX-License-Identifier: GPL-2.0 +.. include:: <isonum.txt> + +===================== +ACPICA Trace Facility +===================== + +:Copyright: |copy| 2015, Intel Corporation +:Author: Lv Zheng <lv.zheng@intel.com> + + +Abstract +======== +This document describes the functions and the interfaces of the +method tracing facility. + +Functionalities and usage examples +================================== + +ACPICA provides method tracing capability. And two functions are +currently implemented using this capability. + +Log reducer +----------- + +ACPICA subsystem provides debugging outputs when CONFIG_ACPI_DEBUG is +enabled. The debugging messages which are deployed via +ACPI_DEBUG_PRINT() macro can be reduced at 2 levels - per-component +level (known as debug layer, configured via +/sys/module/acpi/parameters/debug_layer) and per-type level (known as +debug level, configured via /sys/module/acpi/parameters/debug_level). + +But when the particular layer/level is applied to the control method +evaluations, the quantity of the debugging outputs may still be too +large to be put into the kernel log buffer. The idea thus is worked out +to only enable the particular debug layer/level (normally more detailed) +logs when the control method evaluation is started, and disable the +detailed logging when the control method evaluation is stopped. + +The following command examples illustrate the usage of the "log reducer" +functionality: + +a. Filter out the debug layer/level matched logs when control methods + are being evaluated:: + + # cd /sys/module/acpi/parameters + # echo "0xXXXXXXXX" > trace_debug_layer + # echo "0xYYYYYYYY" > trace_debug_level + # echo "enable" > trace_state + +b. Filter out the debug layer/level matched logs when the specified + control method is being evaluated:: + + # cd /sys/module/acpi/parameters + # echo "0xXXXXXXXX" > trace_debug_layer + # echo "0xYYYYYYYY" > trace_debug_level + # echo "\PPPP.AAAA.TTTT.HHHH" > trace_method_name + # echo "method" > /sys/module/acpi/parameters/trace_state + +c. Filter out the debug layer/level matched logs when the specified + control method is being evaluated for the first time:: + + # cd /sys/module/acpi/parameters + # echo "0xXXXXXXXX" > trace_debug_layer + # echo "0xYYYYYYYY" > trace_debug_level + # echo "\PPPP.AAAA.TTTT.HHHH" > trace_method_name + # echo "method-once" > /sys/module/acpi/parameters/trace_state + +Where: + 0xXXXXXXXX/0xYYYYYYYY + Refer to Documentation/acpi/debug.txt for possible debug layer/level + masking values. + \PPPP.AAAA.TTTT.HHHH + Full path of a control method that can be found in the ACPI namespace. + It needn't be an entry of a control method evaluation. + +AML tracer +---------- + +There are special log entries added by the method tracing facility at +the "trace points" the AML interpreter starts/stops to execute a control +method, or an AML opcode. Note that the format of the log entries are +subject to change:: + + [ 0.186427] exdebug-0398 ex_trace_point : Method Begin [0xf58394d8:\_SB.PCI0.LPCB.ECOK] execution. + [ 0.186630] exdebug-0398 ex_trace_point : Opcode Begin [0xf5905c88:If] execution. + [ 0.186820] exdebug-0398 ex_trace_point : Opcode Begin [0xf5905cc0:LEqual] execution. + [ 0.187010] exdebug-0398 ex_trace_point : Opcode Begin [0xf5905a20:-NamePath-] execution. + [ 0.187214] exdebug-0398 ex_trace_point : Opcode End [0xf5905a20:-NamePath-] execution. + [ 0.187407] exdebug-0398 ex_trace_point : Opcode Begin [0xf5905f60:One] execution. + [ 0.187594] exdebug-0398 ex_trace_point : Opcode End [0xf5905f60:One] execution. + [ 0.187789] exdebug-0398 ex_trace_point : Opcode End [0xf5905cc0:LEqual] execution. + [ 0.187980] exdebug-0398 ex_trace_point : Opcode Begin [0xf5905cc0:Return] execution. + [ 0.188146] exdebug-0398 ex_trace_point : Opcode Begin [0xf5905f60:One] execution. + [ 0.188334] exdebug-0398 ex_trace_point : Opcode End [0xf5905f60:One] execution. + [ 0.188524] exdebug-0398 ex_trace_point : Opcode End [0xf5905cc0:Return] execution. + [ 0.188712] exdebug-0398 ex_trace_point : Opcode End [0xf5905c88:If] execution. + [ 0.188903] exdebug-0398 ex_trace_point : Method End [0xf58394d8:\_SB.PCI0.LPCB.ECOK] execution. + +Developers can utilize these special log entries to track the AML +interpretion, thus can aid issue debugging and performance tuning. Note +that, as the "AML tracer" logs are implemented via ACPI_DEBUG_PRINT() +macro, CONFIG_ACPI_DEBUG is also required to be enabled for enabling +"AML tracer" logs. + +The following command examples illustrate the usage of the "AML tracer" +functionality: + +a. Filter out the method start/stop "AML tracer" logs when control + methods are being evaluated:: + + # cd /sys/module/acpi/parameters + # echo "0x80" > trace_debug_layer + # echo "0x10" > trace_debug_level + # echo "enable" > trace_state + +b. Filter out the method start/stop "AML tracer" when the specified + control method is being evaluated:: + + # cd /sys/module/acpi/parameters + # echo "0x80" > trace_debug_layer + # echo "0x10" > trace_debug_level + # echo "\PPPP.AAAA.TTTT.HHHH" > trace_method_name + # echo "method" > trace_state + +c. Filter out the method start/stop "AML tracer" logs when the specified + control method is being evaluated for the first time:: + + # cd /sys/module/acpi/parameters + # echo "0x80" > trace_debug_layer + # echo "0x10" > trace_debug_level + # echo "\PPPP.AAAA.TTTT.HHHH" > trace_method_name + # echo "method-once" > trace_state + +d. Filter out the method/opcode start/stop "AML tracer" when the + specified control method is being evaluated:: + + # cd /sys/module/acpi/parameters + # echo "0x80" > trace_debug_layer + # echo "0x10" > trace_debug_level + # echo "\PPPP.AAAA.TTTT.HHHH" > trace_method_name + # echo "opcode" > trace_state + +e. Filter out the method/opcode start/stop "AML tracer" when the + specified control method is being evaluated for the first time:: + + # cd /sys/module/acpi/parameters + # echo "0x80" > trace_debug_layer + # echo "0x10" > trace_debug_level + # echo "\PPPP.AAAA.TTTT.HHHH" > trace_method_name + # echo "opcode-opcode" > trace_state + +Note that all above method tracing facility related module parameters can +be used as the boot parameters, for example:: + + acpi.trace_debug_layer=0x80 acpi.trace_debug_level=0x10 \ + acpi.trace_method_name=\_SB.LID0._LID acpi.trace_state=opcode-once + + +Interface descriptions +====================== + +All method tracing functions can be configured via ACPI module +parameters that are accessible at /sys/module/acpi/parameters/: + +trace_method_name + The full path of the AML method that the user wants to trace. + + Note that the full path shouldn't contain the trailing "_"s in its + name segments but may contain "\" to form an absolute path. + +trace_debug_layer + The temporary debug_layer used when the tracing feature is enabled. + + Using ACPI_EXECUTER (0x80) by default, which is the debug_layer + used to match all "AML tracer" logs. + +trace_debug_level + The temporary debug_level used when the tracing feature is enabled. + + Using ACPI_LV_TRACE_POINT (0x10) by default, which is the + debug_level used to match all "AML tracer" logs. + +trace_state + The status of the tracing feature. + + Users can enable/disable this debug tracing feature by executing + the following command:: + + # echo string > /sys/module/acpi/parameters/trace_state + +Where "string" should be one of the following: + +"disable" + Disable the method tracing feature. + +"enable" + Enable the method tracing feature. + + ACPICA debugging messages matching "trace_debug_layer/trace_debug_level" + during any method execution will be logged. + +"method" + Enable the method tracing feature. + + ACPICA debugging messages matching "trace_debug_layer/trace_debug_level" + during method execution of "trace_method_name" will be logged. + +"method-once" + Enable the method tracing feature. + + ACPICA debugging messages matching "trace_debug_layer/trace_debug_level" + during method execution of "trace_method_name" will be logged only once. + +"opcode" + Enable the method tracing feature. + + ACPICA debugging messages matching "trace_debug_layer/trace_debug_level" + during method/opcode execution of "trace_method_name" will be logged. + +"opcode-once" + Enable the method tracing feature. + + ACPICA debugging messages matching "trace_debug_layer/trace_debug_level" + during method/opcode execution of "trace_method_name" will be logged only + once. + +Note that, the difference between the "enable" and other feature +enabling options are: + +1. When "enable" is specified, since + "trace_debug_layer/trace_debug_level" shall apply to all control + method evaluations, after configuring "trace_state" to "enable", + "trace_method_name" will be reset to NULL. +2. When "method/opcode" is specified, if + "trace_method_name" is NULL when "trace_state" is configured to + these options, the "trace_debug_layer/trace_debug_level" will + apply to all control method evaluations. diff --git a/Documentation/acpi/namespace.txt b/Documentation/firmware-guide/acpi/namespace.rst index 1860cb3865c6..835521baeb89 100644 --- a/Documentation/acpi/namespace.txt +++ b/Documentation/firmware-guide/acpi/namespace.rst @@ -1,85 +1,90 @@ +.. SPDX-License-Identifier: GPL-2.0 +.. include:: <isonum.txt> + +=================================================== ACPI Device Tree - Representation of ACPI Namespace +=================================================== -Copyright (C) 2013, Intel Corporation -Author: Lv Zheng <lv.zheng@intel.com> +:Copyright: |copy| 2013, Intel Corporation +:Author: Lv Zheng <lv.zheng@intel.com> -Abstract: +:Credit: Thanks for the help from Zhang Rui <rui.zhang@intel.com> and + Rafael J.Wysocki <rafael.j.wysocki@intel.com>. +Abstract +======== The Linux ACPI subsystem converts ACPI namespace objects into a Linux device tree under the /sys/devices/LNXSYSTEM:00 and updates it upon -receiving ACPI hotplug notification events. For each device object in this -hierarchy there is a corresponding symbolic link in the +receiving ACPI hotplug notification events. For each device object +in this hierarchy there is a corresponding symbolic link in the /sys/bus/acpi/devices. + This document illustrates the structure of the ACPI device tree. +ACPI Definition Blocks +====================== + +The ACPI firmware sets up RSDP (Root System Description Pointer) in the +system memory address space pointing to the XSDT (Extended System +Description Table). The XSDT always points to the FADT (Fixed ACPI +Description Table) using its first entry, the data within the FADT +includes various fixed-length entries that describe fixed ACPI features +of the hardware. The FADT contains a pointer to the DSDT +(Differentiated System Descripition Table). The XSDT also contains +entries pointing to possibly multiple SSDTs (Secondary System +Description Table). + +The DSDT and SSDT data is organized in data structures called definition +blocks that contain definitions of various objects, including ACPI +control methods, encoded in AML (ACPI Machine Language). The data block +of the DSDT along with the contents of SSDTs represents a hierarchical +data structure called the ACPI namespace whose topology reflects the +structure of the underlying hardware platform. + +The relationships between ACPI System Definition Tables described above +are illustrated in the following diagram:: + + +---------+ +-------+ +--------+ +------------------------+ + | RSDP | +->| XSDT | +->| FADT | | +-------------------+ | + +---------+ | +-------+ | +--------+ +-|->| DSDT | | + | Pointer | | | Entry |-+ | ...... | | | +-------------------+ | + +---------+ | +-------+ | X_DSDT |--+ | | Definition Blocks | | + | Pointer |-+ | ..... | | ...... | | +-------------------+ | + +---------+ +-------+ +--------+ | +-------------------+ | + | Entry |------------------|->| SSDT | | + +- - - -+ | +-------------------| | + | Entry | - - - - - - - -+ | | Definition Blocks | | + +- - - -+ | | +-------------------+ | + | | +- - - - - - - - - -+ | + +-|->| SSDT | | + | +-------------------+ | + | | Definition Blocks | | + | +- - - - - - - - - -+ | + +------------------------+ + | + OSPM Loading | + \|/ + +----------------+ + | ACPI Namespace | + +----------------+ + + Figure 1. ACPI Definition Blocks + +.. note:: RSDP can also contain a pointer to the RSDT (Root System + Description Table). Platforms provide RSDT to enable + compatibility with ACPI 1.0 operating systems. The OS is expected + to use XSDT, if present. + + +Example ACPI Namespace +====================== + +All definition blocks are loaded into a single namespace. The namespace +is a hierarchy of objects identified by names and paths. +The following naming conventions apply to object names in the ACPI +namespace: -Credit: - -Thanks for the help from Zhang Rui <rui.zhang@intel.com> and Rafael J. -Wysocki <rafael.j.wysocki@intel.com>. - - -1. ACPI Definition Blocks - - The ACPI firmware sets up RSDP (Root System Description Pointer) in the - system memory address space pointing to the XSDT (Extended System - Description Table). The XSDT always points to the FADT (Fixed ACPI - Description Table) using its first entry, the data within the FADT - includes various fixed-length entries that describe fixed ACPI features - of the hardware. The FADT contains a pointer to the DSDT - (Differentiated System Descripition Table). The XSDT also contains - entries pointing to possibly multiple SSDTs (Secondary System - Description Table). - - The DSDT and SSDT data is organized in data structures called definition - blocks that contain definitions of various objects, including ACPI - control methods, encoded in AML (ACPI Machine Language). The data block - of the DSDT along with the contents of SSDTs represents a hierarchical - data structure called the ACPI namespace whose topology reflects the - structure of the underlying hardware platform. - - The relationships between ACPI System Definition Tables described above - are illustrated in the following diagram. - - +---------+ +-------+ +--------+ +------------------------+ - | RSDP | +->| XSDT | +->| FADT | | +-------------------+ | - +---------+ | +-------+ | +--------+ +-|->| DSDT | | - | Pointer | | | Entry |-+ | ...... | | | +-------------------+ | - +---------+ | +-------+ | X_DSDT |--+ | | Definition Blocks | | - | Pointer |-+ | ..... | | ...... | | +-------------------+ | - +---------+ +-------+ +--------+ | +-------------------+ | - | Entry |------------------|->| SSDT | | - +- - - -+ | +-------------------| | - | Entry | - - - - - - - -+ | | Definition Blocks | | - +- - - -+ | | +-------------------+ | - | | +- - - - - - - - - -+ | - +-|->| SSDT | | - | +-------------------+ | - | | Definition Blocks | | - | +- - - - - - - - - -+ | - +------------------------+ - | - OSPM Loading | - \|/ - +----------------+ - | ACPI Namespace | - +----------------+ - - Figure 1. ACPI Definition Blocks - - NOTE: RSDP can also contain a pointer to the RSDT (Root System - Description Table). Platforms provide RSDT to enable - compatibility with ACPI 1.0 operating systems. The OS is expected - to use XSDT, if present. - - -2. Example ACPI Namespace - - All definition blocks are loaded into a single namespace. The namespace - is a hierarchy of objects identified by names and paths. - The following naming conventions apply to object names in the ACPI - namespace: 1. All names are 32 bits long. 2. The first byte of a name must be one of 'A' - 'Z', '_'. 3. Each of the remaining bytes of a name must be one of 'A' - 'Z', '0' @@ -91,7 +96,7 @@ Wysocki <rafael.j.wysocki@intel.com>. (i.e. names prepended with '^' are relative to the parent of the current namespace node). - The figure below shows an example ACPI namespace. +The figure below shows an example ACPI namespace:: +------+ | \ | Root @@ -184,19 +189,20 @@ Wysocki <rafael.j.wysocki@intel.com>. Figure 2. Example ACPI Namespace -3. Linux ACPI Device Objects +Linux ACPI Device Objects +========================= - The Linux kernel's core ACPI subsystem creates struct acpi_device - objects for ACPI namespace objects representing devices, power resources - processors, thermal zones. Those objects are exported to user space via - sysfs as directories in the subtree under /sys/devices/LNXSYSTM:00. The - format of their names is <bus_id:instance>, where 'bus_id' refers to the - ACPI namespace representation of the given object and 'instance' is used - for distinguishing different object of the same 'bus_id' (it is - two-digit decimal representation of an unsigned integer). +The Linux kernel's core ACPI subsystem creates struct acpi_device +objects for ACPI namespace objects representing devices, power resources +processors, thermal zones. Those objects are exported to user space via +sysfs as directories in the subtree under /sys/devices/LNXSYSTM:00. The +format of their names is <bus_id:instance>, where 'bus_id' refers to the +ACPI namespace representation of the given object and 'instance' is used +for distinguishing different object of the same 'bus_id' (it is +two-digit decimal representation of an unsigned integer). - The value of 'bus_id' depends on the type of the object whose name it is - part of as listed in the table below. +The value of 'bus_id' depends on the type of the object whose name it is +part of as listed in the table below:: +---+-----------------+-------+----------+ | | Object/Feature | Table | bus_id | @@ -226,10 +232,11 @@ Wysocki <rafael.j.wysocki@intel.com>. Table 1. ACPI Namespace Objects Mapping - The following rules apply when creating struct acpi_device objects on - the basis of the contents of ACPI System Description Tables (as - indicated by the letter in the first column and the notation in the - second column of the table above): +The following rules apply when creating struct acpi_device objects on +the basis of the contents of ACPI System Description Tables (as +indicated by the letter in the first column and the notation in the +second column of the table above): + N: The object's source is an ACPI namespace node (as indicated by the named object's type in the second column). In that case the object's @@ -249,13 +256,14 @@ Wysocki <rafael.j.wysocki@intel.com>. struct acpi_device object with LNXVIDEO 'bus_id' will be created for it. - The third column of the above table indicates which ACPI System - Description Tables contain information used for the creation of the - struct acpi_device objects represented by the given row (xSDT means DSDT - or SSDT). +The third column of the above table indicates which ACPI System +Description Tables contain information used for the creation of the +struct acpi_device objects represented by the given row (xSDT means DSDT +or SSDT). + +The forth column of the above table indicates the 'bus_id' generation +rule of the struct acpi_device object: - The forth column of the above table indicates the 'bus_id' generation - rule of the struct acpi_device object: _HID: _HID in the last column of the table means that the object's bus_id is derived from the _HID/_CID identification objects present under @@ -275,45 +283,47 @@ Wysocki <rafael.j.wysocki@intel.com>. object's bus_id. -4. Linux ACPI Physical Device Glue - - ACPI device (i.e. struct acpi_device) objects may be linked to other - objects in the Linux' device hierarchy that represent "physical" devices - (for example, devices on the PCI bus). If that happens, it means that - the ACPI device object is a "companion" of a device otherwise - represented in a different way and is used (1) to provide configuration - information on that device which cannot be obtained by other means and - (2) to do specific things to the device with the help of its ACPI - control methods. One ACPI device object may be linked this way to - multiple "physical" devices. - - If an ACPI device object is linked to a "physical" device, its sysfs - directory contains the "physical_node" symbolic link to the sysfs - directory of the target device object. In turn, the target device's - sysfs directory will then contain the "firmware_node" symbolic link to - the sysfs directory of the companion ACPI device object. - The linking mechanism relies on device identification provided by the - ACPI namespace. For example, if there's an ACPI namespace object - representing a PCI device (i.e. a device object under an ACPI namespace - object representing a PCI bridge) whose _ADR returns 0x00020000 and the - bus number of the parent PCI bridge is 0, the sysfs directory - representing the struct acpi_device object created for that ACPI - namespace object will contain the 'physical_node' symbolic link to the - /sys/devices/pci0000:00/0000:00:02:0/ sysfs directory of the - corresponding PCI device. - - The linking mechanism is generally bus-specific. The core of its - implementation is located in the drivers/acpi/glue.c file, but there are - complementary parts depending on the bus types in question located - elsewhere. For example, the PCI-specific part of it is located in - drivers/pci/pci-acpi.c. - - -5. Example Linux ACPI Device Tree - - The sysfs hierarchy of struct acpi_device objects corresponding to the - example ACPI namespace illustrated in Figure 2 with the addition of - fixed PWR_BUTTON/SLP_BUTTON devices is shown below. +Linux ACPI Physical Device Glue +=============================== + +ACPI device (i.e. struct acpi_device) objects may be linked to other +objects in the Linux' device hierarchy that represent "physical" devices +(for example, devices on the PCI bus). If that happens, it means that +the ACPI device object is a "companion" of a device otherwise +represented in a different way and is used (1) to provide configuration +information on that device which cannot be obtained by other means and +(2) to do specific things to the device with the help of its ACPI +control methods. One ACPI device object may be linked this way to +multiple "physical" devices. + +If an ACPI device object is linked to a "physical" device, its sysfs +directory contains the "physical_node" symbolic link to the sysfs +directory of the target device object. In turn, the target device's +sysfs directory will then contain the "firmware_node" symbolic link to +the sysfs directory of the companion ACPI device object. +The linking mechanism relies on device identification provided by the +ACPI namespace. For example, if there's an ACPI namespace object +representing a PCI device (i.e. a device object under an ACPI namespace +object representing a PCI bridge) whose _ADR returns 0x00020000 and the +bus number of the parent PCI bridge is 0, the sysfs directory +representing the struct acpi_device object created for that ACPI +namespace object will contain the 'physical_node' symbolic link to the +/sys/devices/pci0000:00/0000:00:02:0/ sysfs directory of the +corresponding PCI device. + +The linking mechanism is generally bus-specific. The core of its +implementation is located in the drivers/acpi/glue.c file, but there are +complementary parts depending on the bus types in question located +elsewhere. For example, the PCI-specific part of it is located in +drivers/pci/pci-acpi.c. + + +Example Linux ACPI Device Tree +================================= + +The sysfs hierarchy of struct acpi_device objects corresponding to the +example ACPI namespace illustrated in Figure 2 with the addition of +fixed PWR_BUTTON/SLP_BUTTON devices is shown below:: +--------------+---+-----------------+ | LNXSYSTEM:00 | \ | acpi:LNXSYSTEM: | @@ -377,12 +387,14 @@ Wysocki <rafael.j.wysocki@intel.com>. Figure 3. Example Linux ACPI Device Tree - NOTE: Each node is represented as "object/path/modalias", where: - 1. 'object' is the name of the object's directory in sysfs. - 2. 'path' is the ACPI namespace path of the corresponding - ACPI namespace object, as returned by the object's 'path' - sysfs attribute. - 3. 'modalias' is the value of the object's 'modalias' sysfs - attribute (as described earlier in this document). - NOTE: N/A indicates the device object does not have the 'path' or the - 'modalias' attribute. +.. note:: Each node is represented as "object/path/modalias", where: + + 1. 'object' is the name of the object's directory in sysfs. + 2. 'path' is the ACPI namespace path of the corresponding + ACPI namespace object, as returned by the object's 'path' + sysfs attribute. + 3. 'modalias' is the value of the object's 'modalias' sysfs + attribute (as described earlier in this document). + +.. note:: N/A indicates the device object does not have the 'path' or the + 'modalias' attribute. diff --git a/Documentation/acpi/osi.txt b/Documentation/firmware-guide/acpi/osi.rst index 50cde0ceb9b0..29e9ef79ebc0 100644 --- a/Documentation/acpi/osi.txt +++ b/Documentation/firmware-guide/acpi/osi.rst @@ -1,5 +1,8 @@ +.. SPDX-License-Identifier: GPL-2.0 + +========================== ACPI _OSI and _REV methods --------------------------- +========================== An ACPI BIOS can use the "Operating System Interfaces" method (_OSI) to find out what the operating system supports. Eg. If BIOS @@ -14,7 +17,7 @@ This document explains how and why the BIOS and Linux should use these methods. It also explains how and why they are widely misused. How to use _OSI ---------------- +=============== Linux runs on two groups of machines -- those that are tested by the OEM to be compatible with Linux, and those that were never tested with Linux, @@ -62,7 +65,7 @@ the string when that support is added to the kernel. That was easy. Read on, to find out how to do it wrong. Before _OSI, there was _OS --------------------------- +========================== ACPI 1.0 specified "_OS" as an "object that evaluates to a string that identifies the operating system." @@ -96,7 +99,7 @@ That is the *only* viable strategy, as that is what modern Windows does, and so doing otherwise could steer the BIOS down an untested path. _OSI is born, and immediately misused --------------------------------------- +===================================== With _OSI, the *BIOS* provides the string describing an interface, and asks the OS: "YES/NO, are you compatible with this interface?" @@ -144,7 +147,7 @@ catastrophic failure resulting from the BIOS taking paths that were never validated under *any* OS. Do not use _REV ---------------- +=============== Since _OSI("Linux") went away, some BIOS writers used _REV to support Linux and Windows differences in the same BIOS. @@ -164,7 +167,7 @@ from mid-2015 onward. The ACPI specification will also be updated to reflect that _REV is deprecated, and always returns 2. Apple Mac and _OSI("Darwin") ----------------------------- +============================ On Apple's Mac platforms, the ACPI BIOS invokes _OSI("Darwin") to determine if the machine is running Apple OSX. diff --git a/Documentation/acpi/video_extension.txt b/Documentation/firmware-guide/acpi/video_extension.rst index 79bf6a4921be..099b8607e07b 100644 --- a/Documentation/acpi/video_extension.txt +++ b/Documentation/firmware-guide/acpi/video_extension.rst @@ -1,5 +1,8 @@ +.. SPDX-License-Identifier: GPL-2.0 + +===================== ACPI video extensions -~~~~~~~~~~~~~~~~~~~~~ +===================== This driver implement the ACPI Extensions For Display Adapters for integrated graphics devices on motherboard, as specified in ACPI 2.0 @@ -8,9 +11,10 @@ defining the video POST device, retrieving EDID information or to setup a video output, etc. Note that this is an ref. implementation only. It may or may not work for your integrated video device. -The ACPI video driver does 3 things regarding backlight control: +The ACPI video driver does 3 things regarding backlight control. -1 Export a sysfs interface for user space to control backlight level +Export a sysfs interface for user space to control backlight level +================================================================== If the ACPI table has a video device, and acpi_backlight=vendor kernel command line is not present, the driver will register a backlight device @@ -22,36 +26,41 @@ The backlight sysfs interface has a standard definition here: Documentation/ABI/stable/sysfs-class-backlight. And what ACPI video driver does is: -actual_brightness: on read, control method _BQC will be evaluated to -get the brightness level the firmware thinks it is at; -bl_power: not implemented, will set the current brightness instead; -brightness: on write, control method _BCM will run to set the requested -brightness level; -max_brightness: Derived from the _BCL package(see below); -type: firmware + +actual_brightness: + on read, control method _BQC will be evaluated to + get the brightness level the firmware thinks it is at; +bl_power: + not implemented, will set the current brightness instead; +brightness: + on write, control method _BCM will run to set the requested brightness level; +max_brightness: + Derived from the _BCL package(see below); +type: + firmware Note that ACPI video backlight driver will always use index for brightness, actual_brightness and max_brightness. So if we have -the following _BCL package: +the following _BCL package:: -Method (_BCL, 0, NotSerialized) -{ - Return (Package (0x0C) + Method (_BCL, 0, NotSerialized) { - 0x64, - 0x32, - 0x0A, - 0x14, - 0x1E, - 0x28, - 0x32, - 0x3C, - 0x46, - 0x50, - 0x5A, - 0x64 - }) -} + Return (Package (0x0C) + { + 0x64, + 0x32, + 0x0A, + 0x14, + 0x1E, + 0x28, + 0x32, + 0x3C, + 0x46, + 0x50, + 0x5A, + 0x64 + }) + } The first two levels are for when laptop are on AC or on battery and are not used by Linux currently. The remaining 10 levels are supported levels @@ -62,13 +71,15 @@ as a "brightness level" indicator. Thus from the user space perspective the range of available brightness levels is from 0 to 9 (max_brightness) inclusive. -2 Notify user space about hotkey event +Notify user space about hotkey event +==================================== There are generally two cases for hotkey event reporting: + i) For some laptops, when user presses the hotkey, a scancode will be generated and sent to user space through the input device created by the keyboard driver as a key type input event, with proper remap, the - following key code will appear to user space: + following key code will appear to user space:: EV_KEY, KEY_BRIGHTNESSUP EV_KEY, KEY_BRIGHTNESSDOWN @@ -84,23 +95,27 @@ ii) For some laptops, the press of the hotkey will not generate the notify value it received and send the event to user space through the input device it created: + ===== ================== event keycode + ===== ================== 0x86 KEY_BRIGHTNESSUP 0x87 KEY_BRIGHTNESSDOWN etc. + ===== ================== so this would lead to the same effect as case i) now. Once user space tool receives this event, it can modify the backlight level through the sysfs interface. -3 Change backlight level in the kernel +Change backlight level in the kernel +==================================== This works for machines covered by case ii) in Section 2. Once the driver received a notification, it will set the backlight level accordingly. This does not affect the sending of event to user space, they are always sent to user space regardless of whether or not the video module controls the backlight level directly. This behaviour can be controlled through the brightness_switch_enabled -module parameter as documented in admin-guide/kernel-parameters.rst. It is recommended to -disable this behaviour once a GUI environment starts up and wants to have full -control of the backlight level. +module parameter as documented in admin-guide/kernel-parameters.rst. It is +recommended to disable this behaviour once a GUI environment starts up and +wants to have full control of the backlight level. diff --git a/Documentation/firmware-guide/index.rst b/Documentation/firmware-guide/index.rst new file mode 100644 index 000000000000..5355784ca0a2 --- /dev/null +++ b/Documentation/firmware-guide/index.rst @@ -0,0 +1,13 @@ +.. SPDX-License-Identifier: GPL-2.0 + +=============================== +The Linux kernel firmware guide +=============================== + +This section describes the ACPI subsystem in Linux from firmware perspective. + +.. toctree:: + :maxdepth: 1 + + acpi/index + diff --git a/Documentation/index.rst b/Documentation/index.rst index 3a710dc24fc8..fec80fee512a 100644 --- a/Documentation/index.rst +++ b/Documentation/index.rst @@ -35,6 +35,16 @@ trying to get it to work optimally on a given system. admin-guide/index +Firmware-related documentation +------------------------------ +The following holds information on the kernel's expectations regarding the +platform firmwares. + +.. toctree:: + :maxdepth: 2 + + firmware-guide/index + Application-developer documentation ----------------------------------- diff --git a/Documentation/kprobes.txt b/Documentation/kprobes.txt index 10f4499e677c..ee60e519438a 100644 --- a/Documentation/kprobes.txt +++ b/Documentation/kprobes.txt @@ -243,10 +243,10 @@ Optimization ^^^^^^^^^^^^ The Kprobe-optimizer doesn't insert the jump instruction immediately; -rather, it calls synchronize_sched() for safety first, because it's +rather, it calls synchronize_rcu() for safety first, because it's possible for a CPU to be interrupted in the middle of executing the -optimized region [3]_. As you know, synchronize_sched() can ensure -that all interruptions that were active when synchronize_sched() +optimized region [3]_. As you know, synchronize_rcu() can ensure +that all interruptions that were active when synchronize_rcu() was called are done, but only if CONFIG_PREEMPT=n. So, this version of kprobe optimization supports only kernels with CONFIG_PREEMPT=n [4]_. diff --git a/Documentation/media/uapi/rc/rc-tables.rst b/Documentation/media/uapi/rc/rc-tables.rst index f460031d8531..177ac44fa0fa 100644 --- a/Documentation/media/uapi/rc/rc-tables.rst +++ b/Documentation/media/uapi/rc/rc-tables.rst @@ -623,7 +623,7 @@ the remote via /dev/input/event devices. - .. row 78 - - ``KEY_SCREEN`` + - ``KEY_ASPECT_RATIO`` - Select screen aspect ratio @@ -631,7 +631,7 @@ the remote via /dev/input/event devices. - .. row 79 - - ``KEY_ZOOM`` + - ``KEY_FULL_SCREEN`` - Put device into zoom/full screen mode diff --git a/Documentation/memory-barriers.txt b/Documentation/memory-barriers.txt index 1c22b21ae922..f70ebcdfe592 100644 --- a/Documentation/memory-barriers.txt +++ b/Documentation/memory-barriers.txt @@ -1937,21 +1937,6 @@ There are some more advanced barrier functions: information on consistent memory. -MMIO WRITE BARRIER ------------------- - -The Linux kernel also has a special barrier for use with memory-mapped I/O -writes: - - mmiowb(); - -This is a variation on the mandatory write barrier that causes writes to weakly -ordered I/O regions to be partially ordered. Its effects may go beyond the -CPU->Hardware interface and actually affect the hardware at some level. - -See the subsection "Acquires vs I/O accesses" for more information. - - =============================== IMPLICIT KERNEL MEMORY BARRIERS =============================== @@ -2317,75 +2302,6 @@ But it won't see any of: *E, *F or *G following RELEASE Q - -ACQUIRES VS I/O ACCESSES ------------------------- - -Under certain circumstances (especially involving NUMA), I/O accesses within -two spinlocked sections on two different CPUs may be seen as interleaved by the -PCI bridge, because the PCI bridge does not necessarily participate in the -cache-coherence protocol, and is therefore incapable of issuing the required -read memory barriers. - -For example: - - CPU 1 CPU 2 - =============================== =============================== - spin_lock(Q) - writel(0, ADDR) - writel(1, DATA); - spin_unlock(Q); - spin_lock(Q); - writel(4, ADDR); - writel(5, DATA); - spin_unlock(Q); - -may be seen by the PCI bridge as follows: - - STORE *ADDR = 0, STORE *ADDR = 4, STORE *DATA = 1, STORE *DATA = 5 - -which would probably cause the hardware to malfunction. - - -What is necessary here is to intervene with an mmiowb() before dropping the -spinlock, for example: - - CPU 1 CPU 2 - =============================== =============================== - spin_lock(Q) - writel(0, ADDR) - writel(1, DATA); - mmiowb(); - spin_unlock(Q); - spin_lock(Q); - writel(4, ADDR); - writel(5, DATA); - mmiowb(); - spin_unlock(Q); - -this will ensure that the two stores issued on CPU 1 appear at the PCI bridge -before either of the stores issued on CPU 2. - - -Furthermore, following a store by a load from the same device obviates the need -for the mmiowb(), because the load forces the store to complete before the load -is performed: - - CPU 1 CPU 2 - =============================== =============================== - spin_lock(Q) - writel(0, ADDR) - a = readl(DATA); - spin_unlock(Q); - spin_lock(Q); - writel(4, ADDR); - b = readl(DATA); - spin_unlock(Q); - - -See Documentation/driver-api/device-io.rst for more information. - - ================================= WHERE ARE MEMORY BARRIERS NEEDED? ================================= @@ -2532,16 +2448,9 @@ the device to malfunction. Inside of the Linux kernel, I/O should be done through the appropriate accessor routines - such as inb() or writel() - which know how to make such accesses appropriately sequential. While this, for the most part, renders the explicit -use of memory barriers unnecessary, there are a couple of situations where they -might be needed: - - (1) On some systems, I/O stores are not strongly ordered across all CPUs, and - so for _all_ general drivers locks should be used and mmiowb() must be - issued prior to unlocking the critical section. - - (2) If the accessor functions are used to refer to an I/O memory window with - relaxed memory access properties, then _mandatory_ memory barriers are - required to enforce ordering. +use of memory barriers unnecessary, if the accessor functions are used to refer +to an I/O memory window with relaxed memory access properties, then _mandatory_ +memory barriers are required to enforce ordering. See Documentation/driver-api/device-io.rst for more information. @@ -2586,8 +2495,7 @@ explicit barriers are used. Normally this won't be a problem because the I/O accesses done inside such sections will include synchronous load operations on strictly ordered I/O -registers that form implicit I/O barriers. If this isn't sufficient then an -mmiowb() may need to be used explicitly. +registers that form implicit I/O barriers. A similar situation may occur between an interrupt routine and two routines @@ -2599,71 +2507,114 @@ likely, then interrupt-disabling locks should be used to guarantee ordering. KERNEL I/O BARRIER EFFECTS ========================== -When accessing I/O memory, drivers should use the appropriate accessor -functions: - - (*) inX(), outX(): - - These are intended to talk to I/O space rather than memory space, but - that's primarily a CPU-specific concept. The i386 and x86_64 processors - do indeed have special I/O space access cycles and instructions, but many - CPUs don't have such a concept. - - The PCI bus, amongst others, defines an I/O space concept which - on such - CPUs as i386 and x86_64 - readily maps to the CPU's concept of I/O - space. However, it may also be mapped as a virtual I/O space in the CPU's - memory map, particularly on those CPUs that don't support alternate I/O - spaces. - - Accesses to this space may be fully synchronous (as on i386), but - intermediary bridges (such as the PCI host bridge) may not fully honour - that. - - They are guaranteed to be fully ordered with respect to each other. - - They are not guaranteed to be fully ordered with respect to other types of - memory and I/O operation. +Interfacing with peripherals via I/O accesses is deeply architecture and device +specific. Therefore, drivers which are inherently non-portable may rely on +specific behaviours of their target systems in order to achieve synchronization +in the most lightweight manner possible. For drivers intending to be portable +between multiple architectures and bus implementations, the kernel offers a +series of accessor functions that provide various degrees of ordering +guarantees: (*) readX(), writeX(): - Whether these are guaranteed to be fully ordered and uncombined with - respect to each other on the issuing CPU depends on the characteristics - defined for the memory window through which they're accessing. On later - i386 architecture machines, for example, this is controlled by way of the - MTRR registers. + The readX() and writeX() MMIO accessors take a pointer to the + peripheral being accessed as an __iomem * parameter. For pointers + mapped with the default I/O attributes (e.g. those returned by + ioremap()), the ordering guarantees are as follows: + + 1. All readX() and writeX() accesses to the same peripheral are ordered + with respect to each other. This ensures that MMIO register accesses + by the same CPU thread to a particular device will arrive in program + order. + + 2. A writeX() issued by a CPU thread holding a spinlock is ordered + before a writeX() to the same peripheral from another CPU thread + issued after a later acquisition of the same spinlock. This ensures + that MMIO register writes to a particular device issued while holding + a spinlock will arrive in an order consistent with acquisitions of + the lock. + + 3. A writeX() by a CPU thread to the peripheral will first wait for the + completion of all prior writes to memory either issued by, or + propagated to, the same thread. This ensures that writes by the CPU + to an outbound DMA buffer allocated by dma_alloc_coherent() will be + visible to a DMA engine when the CPU writes to its MMIO control + register to trigger the transfer. + + 4. A readX() by a CPU thread from the peripheral will complete before + any subsequent reads from memory by the same thread can begin. This + ensures that reads by the CPU from an incoming DMA buffer allocated + by dma_alloc_coherent() will not see stale data after reading from + the DMA engine's MMIO status register to establish that the DMA + transfer has completed. + + 5. A readX() by a CPU thread from the peripheral will complete before + any subsequent delay() loop can begin execution on the same thread. + This ensures that two MMIO register writes by the CPU to a peripheral + will arrive at least 1us apart if the first write is immediately read + back with readX() and udelay(1) is called prior to the second + writeX(): + + writel(42, DEVICE_REGISTER_0); // Arrives at the device... + readl(DEVICE_REGISTER_0); + udelay(1); + writel(42, DEVICE_REGISTER_1); // ...at least 1us before this. + + The ordering properties of __iomem pointers obtained with non-default + attributes (e.g. those returned by ioremap_wc()) are specific to the + underlying architecture and therefore the guarantees listed above cannot + generally be relied upon for accesses to these types of mappings. + + (*) readX_relaxed(), writeX_relaxed(): + + These are similar to readX() and writeX(), but provide weaker memory + ordering guarantees. Specifically, they do not guarantee ordering with + respect to locking, normal memory accesses or delay() loops (i.e. + bullets 2-5 above) but they are still guaranteed to be ordered with + respect to other accesses from the same CPU thread to the same + peripheral when operating on __iomem pointers mapped with the default + I/O attributes. + + (*) readsX(), writesX(): + + The readsX() and writesX() MMIO accessors are designed for accessing + register-based, memory-mapped FIFOs residing on peripherals that are not + capable of performing DMA. Consequently, they provide only the ordering + guarantees of readX_relaxed() and writeX_relaxed(), as documented above. - Ordinarily, these will be guaranteed to be fully ordered and uncombined, - provided they're not accessing a prefetchable device. + (*) inX(), outX(): - However, intermediary hardware (such as a PCI bridge) may indulge in - deferral if it so wishes; to flush a store, a load from the same location - is preferred[*], but a load from the same device or from configuration - space should suffice for PCI. + The inX() and outX() accessors are intended to access legacy port-mapped + I/O peripherals, which may require special instructions on some + architectures (notably x86). The port number of the peripheral being + accessed is passed as an argument. - [*] NOTE! attempting to load from the same location as was written to may - cause a malfunction - consider the 16550 Rx/Tx serial registers for - example. + Since many CPU architectures ultimately access these peripherals via an + internal virtual memory mapping, the portable ordering guarantees + provided by inX() and outX() are the same as those provided by readX() + and writeX() respectively when accessing a mapping with the default I/O + attributes. - Used with prefetchable I/O memory, an mmiowb() barrier may be required to - force stores to be ordered. + Device drivers may expect outX() to emit a non-posted write transaction + that waits for a completion response from the I/O peripheral before + returning. This is not guaranteed by all architectures and is therefore + not part of the portable ordering semantics. - Please refer to the PCI specification for more information on interactions - between PCI transactions. + (*) insX(), outsX(): - (*) readX_relaxed(), writeX_relaxed() + As above, the insX() and outsX() accessors provide the same ordering + guarantees as readsX() and writesX() respectively when accessing a + mapping with the default I/O attributes. - These are similar to readX() and writeX(), but provide weaker memory - ordering guarantees. Specifically, they do not guarantee ordering with - respect to normal memory accesses (e.g. DMA buffers) nor do they guarantee - ordering with respect to LOCK or UNLOCK operations. If the latter is - required, an mmiowb() barrier can be used. Note that relaxed accesses to - the same peripheral are guaranteed to be ordered with respect to each - other. + (*) ioreadX(), iowriteX(): - (*) ioreadX(), iowriteX() + These will perform appropriately for the type of access they're actually + doing, be it inX()/outX() or readX()/writeX(). - These will perform appropriately for the type of access they're actually - doing, be it inX()/outX() or readX()/writeX(). +With the exception of the string accessors (insX(), outsX(), readsX() and +writesX()), all of the above assume that the underlying peripheral is +little-endian and will therefore perform byte-swapping operations on big-endian +architectures. ======================================== diff --git a/Documentation/networking/decnet.txt b/Documentation/networking/decnet.txt index e12a4900cf72..d192f8b9948b 100644 --- a/Documentation/networking/decnet.txt +++ b/Documentation/networking/decnet.txt @@ -22,8 +22,6 @@ you'll need the following options as well... CONFIG_DECNET_ROUTER (to be able to add/delete routes) CONFIG_NETFILTER (will be required for the DECnet routing daemon) - CONFIG_DECNET_ROUTE_FWMARK is optional - Don't turn on SIOCGIFCONF support for DECnet unless you are really sure that you need it, in general you won't and it can cause ifconfig to malfunction. diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index acdfb5d2bcaa..c4ac35234f05 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -422,6 +422,7 @@ tcp_min_rtt_wlen - INTEGER minimum RTT when it is moved to a longer path (e.g., due to traffic engineering). A longer window makes the filter more resistant to RTT inflations such as transient congestion. The unit is seconds. + Possible values: 0 - 86400 (1 day) Default: 300 tcp_moderate_rcvbuf - BOOLEAN @@ -1336,6 +1337,7 @@ tag - INTEGER Default value is 0. xfrm4_gc_thresh - INTEGER + (Obsolete since linux-4.14) The threshold at which we will start garbage collecting for IPv4 destination cache entries. At twice this value the system will refuse new allocations. @@ -1919,6 +1921,7 @@ echo_ignore_all - BOOLEAN Default: 0 xfrm6_gc_thresh - INTEGER + (Obsolete since linux-4.14) The threshold at which we will start garbage collecting for IPv6 destination cache entries. At twice this value the system will refuse new allocations. diff --git a/Documentation/networking/netdev-FAQ.rst b/Documentation/networking/netdev-FAQ.rst index 8c7a713cf657..642fa963be3c 100644 --- a/Documentation/networking/netdev-FAQ.rst +++ b/Documentation/networking/netdev-FAQ.rst @@ -132,7 +132,7 @@ version that should be applied. If there is any doubt, the maintainer will reply and ask what should be done. Q: I made changes to only a few patches in a patch series should I resend only those changed? --------------------------------------------------------------------------------------------- +--------------------------------------------------------------------------------------------- A: No, please resend the entire patch series and make sure you do number your patches such that it is clear this is the latest and greatest set of patches that can be applied. diff --git a/Documentation/networking/rxrpc.txt b/Documentation/networking/rxrpc.txt index 2df5894353d6..cd7303d7fa25 100644 --- a/Documentation/networking/rxrpc.txt +++ b/Documentation/networking/rxrpc.txt @@ -1009,16 +1009,18 @@ The kernel interface functions are as follows: (*) Check call still alive. - u32 rxrpc_kernel_check_life(struct socket *sock, - struct rxrpc_call *call); + bool rxrpc_kernel_check_life(struct socket *sock, + struct rxrpc_call *call, + u32 *_life); void rxrpc_kernel_probe_life(struct socket *sock, struct rxrpc_call *call); - The first function returns a number that is updated when ACKs are received - from the peer (notably including PING RESPONSE ACKs which we can elicit by - sending PING ACKs to see if the call still exists on the server). The - caller should compare the numbers of two calls to see if the call is still - alive after waiting for a suitable interval. + The first function passes back in *_life a number that is updated when + ACKs are received from the peer (notably including PING RESPONSE ACKs + which we can elicit by sending PING ACKs to see if the call still exists + on the server). The caller should compare the numbers of two calls to see + if the call is still alive after waiting for a suitable interval. It also + returns true as long as the call hasn't yet reached the completed state. This allows the caller to work out if the server is still contactable and if the call is still alive on the server while waiting for the server to diff --git a/Documentation/robust-futexes.txt b/Documentation/robust-futexes.txt index 6c42c75103eb..6361fb01c9c1 100644 --- a/Documentation/robust-futexes.txt +++ b/Documentation/robust-futexes.txt @@ -218,5 +218,4 @@ All other architectures should build just fine too - but they won't have the new syscalls yet. Architectures need to implement the new futex_atomic_cmpxchg_inatomic() -inline function before writing up the syscalls (that function returns --ENOSYS right now). +inline function before writing up the syscalls. diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt index 6af24cdb25cc..3f13d8599337 100644 --- a/Documentation/sysctl/vm.txt +++ b/Documentation/sysctl/vm.txt @@ -866,14 +866,14 @@ The intent is that compaction has less work to do in the future and to increase the success rate of future high-order allocations such as SLUB allocations, THP and hugetlbfs pages. -To make it sensible with respect to the watermark_scale_factor parameter, -the unit is in fractions of 10,000. The default value of 15,000 means -that up to 150% of the high watermark will be reclaimed in the event of -a pageblock being mixed due to fragmentation. The level of reclaim is -determined by the number of fragmentation events that occurred in the -recent past. If this value is smaller than a pageblock then a pageblocks -worth of pages will be reclaimed (e.g. 2MB on 64-bit x86). A boost factor -of 0 will disable the feature. +To make it sensible with respect to the watermark_scale_factor +parameter, the unit is in fractions of 10,000. The default value of +15,000 on !DISCONTIGMEM configurations means that up to 150% of the high +watermark will be reclaimed in the event of a pageblock being mixed due +to fragmentation. The level of reclaim is determined by the number of +fragmentation events that occurred in the recent past. If this value is +smaller than a pageblock then a pageblocks worth of pages will be reclaimed +(e.g. 2MB on 64-bit x86). A boost factor of 0 will disable the feature. ============================================================= diff --git a/Documentation/translations/ko_KR/memory-barriers.txt b/Documentation/translations/ko_KR/memory-barriers.txt index 7f01fb1c1084..db0b9d8619f1 100644 --- a/Documentation/translations/ko_KR/memory-barriers.txt +++ b/Documentation/translations/ko_KR/memory-barriers.txt @@ -493,10 +493,8 @@ CPU 에게 기대할 수 있는 최소한의 보장사항 몇가지가 있습니 이 타입의 오퍼레이션은 단방향의 투과성 배리어처럼 동작합니다. ACQUIRE 오퍼레이션 뒤의 모든 메모리 오퍼레이션들이 ACQUIRE 오퍼레이션 후에 일어난 것으로 시스템의 나머지 컴포넌트들에 보이게 될 것이 보장됩니다. - LOCK 오퍼레이션과 smp_load_acquire(), smp_cond_acquire() 오퍼레이션도 - ACQUIRE 오퍼레이션에 포함됩니다. smp_cond_acquire() 오퍼레이션은 컨트롤 - 의존성과 smp_rmb() 를 사용해서 ACQUIRE 의 의미적 요구사항(semantic)을 - 충족시킵니다. + LOCK 오퍼레이션과 smp_load_acquire(), smp_cond_load_acquire() 오퍼레이션도 + ACQUIRE 오퍼레이션에 포함됩니다. ACQUIRE 오퍼레이션 앞의 메모리 오퍼레이션들은 ACQUIRE 오퍼레이션 완료 후에 수행된 것처럼 보일 수 있습니다. @@ -2146,33 +2144,40 @@ set_current_state() 는 다음의 것들로 감싸질 수도 있습니다: event_indicated = 1; wake_up_process(event_daemon); -wake_up() 류에 의해 쓰기 메모리 배리어가 내포됩니다. 만약 그것들이 뭔가를 -깨운다면요. 이 배리어는 태스크 상태가 지워지기 전에 수행되므로, 이벤트를 -알리기 위한 STORE 와 태스크 상태를 TASK_RUNNING 으로 설정하는 STORE 사이에 -위치하게 됩니다. +wake_up() 이 무언가를 깨우게 되면, 이 함수는 범용 메모리 배리어를 수행합니다. +이 함수가 아무것도 깨우지 않는다면 메모리 배리어는 수행될 수도, 수행되지 않을 +수도 있습니다; 이 경우에 메모리 배리어를 수행할 거라 오해해선 안됩니다. 이 +배리어는 태스크 상태가 접근되기 전에 수행되는데, 자세히 말하면 이 이벤트를 +알리기 위한 STORE 와 TASK_RUNNING 으로 상태를 쓰는 STORE 사이에 수행됩니다: - CPU 1 CPU 2 + CPU 1 (Sleeper) CPU 2 (Waker) =============================== =============================== set_current_state(); STORE event_indicated smp_store_mb(); wake_up(); - STORE current->state <쓰기 배리어> - <범용 배리어> STORE current->state - LOAD event_indicated + STORE current->state ... + <범용 배리어> <범용 배리어> + LOAD event_indicated if ((LOAD task->state) & TASK_NORMAL) + STORE task->state -한번더 말합니다만, 이 쓰기 메모리 배리어는 이 코드가 정말로 뭔가를 깨울 때에만 -실행됩니다. 이걸 설명하기 위해, X 와 Y 는 모두 0 으로 초기화 되어 있다는 가정 -하에 아래의 이벤트 시퀀스를 생각해 봅시다: +여기서 "task" 는 깨어나지는 쓰레드이고 CPU 1 의 "current" 와 같습니다. + +반복하지만, wake_up() 이 무언가를 정말 깨운다면 범용 메모리 배리어가 수행될 +것이 보장되지만, 그렇지 않다면 그런 보장이 없습니다. 이걸 이해하기 위해, X 와 +Y 는 모두 0 으로 초기화 되어 있다는 가정 하에 아래의 이벤트 시퀀스를 생각해 +봅시다: CPU 1 CPU 2 =============================== =============================== - X = 1; STORE event_indicated + X = 1; Y = 1; smp_mb(); wake_up(); - Y = 1; wait_event(wq, Y == 1); - wake_up(); load from Y sees 1, no memory barrier - load from X might see 0 + LOAD Y LOAD X + +정말로 깨우기가 행해졌다면, 두 로드 중 (최소한) 하나는 1 을 보게 됩니다. +반면에, 실제 깨우기가 행해지지 않았다면, 두 로드 모두 0을 볼 수도 있습니다. -위 예제에서의 경우와 달리 깨우기가 정말로 행해졌다면, CPU 2 의 X 로드는 1 을 -본다고 보장될 수 있을 겁니다. +wake_up_process() 는 항상 범용 메모리 배리어를 수행합니다. 이 배리어 역시 +태스크 상태가 접근되기 전에 수행됩니다. 특히, 앞의 예제 코드에서 wake_up() 이 +wake_up_process() 로 대체된다면 두 로드 중 하나는 1을 볼 것이 보장됩니다. 사용 가능한 깨우기류 함수들로 다음과 같은 것들이 있습니다: @@ -2192,6 +2197,8 @@ wake_up() 류에 의해 쓰기 메모리 배리어가 내포됩니다. 만약 wake_up_poll(); wake_up_process(); +메모리 순서규칙 관점에서, 이 함수들은 모두 wake_up() 과 같거나 보다 강한 순서 +보장을 제공합니다. [!] 잠재우는 코드와 깨우는 코드에 내포되는 메모리 배리어들은 깨우기 전에 이루어진 스토어를 잠재우는 코드가 set_current_state() 를 호출한 후에 행하는 diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt index 67068c47c591..64b38dfcc243 100644 --- a/Documentation/virtual/kvm/api.txt +++ b/Documentation/virtual/kvm/api.txt @@ -321,7 +321,7 @@ cpu's hardware control block. 4.8 KVM_GET_DIRTY_LOG (vm ioctl) Capability: basic -Architectures: x86 +Architectures: all Type: vm ioctl Parameters: struct kvm_dirty_log (in/out) Returns: 0 on success, -1 on error @@ -3810,7 +3810,7 @@ to I/O ports. 4.117 KVM_CLEAR_DIRTY_LOG (vm ioctl) Capability: KVM_CAP_MANUAL_DIRTY_LOG_PROTECT -Architectures: x86 +Architectures: x86, arm, arm64, mips Type: vm ioctl Parameters: struct kvm_dirty_log (in) Returns: 0 on success, -1 on error @@ -3830,8 +3830,9 @@ The ioctl clears the dirty status of pages in a memory slot, according to the bitmap that is passed in struct kvm_clear_dirty_log's dirty_bitmap field. Bit 0 of the bitmap corresponds to page "first_page" in the memory slot, and num_pages is the size in bits of the input bitmap. -Both first_page and num_pages must be a multiple of 64. For each bit -that is set in the input bitmap, the corresponding page is marked "clean" +first_page must be a multiple of 64; num_pages must also be a multiple of +64 unless first_page + num_pages is the size of the memory slot. For each +bit that is set in the input bitmap, the corresponding page is marked "clean" in KVM's dirty bitmap, and dirty tracking is re-enabled for that page (for example via write-protection, or by clearing the dirty bit in a page table entry). @@ -4799,7 +4800,7 @@ and injected exceptions. 7.18 KVM_CAP_MANUAL_DIRTY_LOG_PROTECT -Architectures: all +Architectures: x86, arm, arm64, mips Parameters: args[0] whether feature should be enabled or not With this capability enabled, KVM_GET_DIRTY_LOG will not automatically diff --git a/Documentation/x86/kernel-stacks b/Documentation/x86/kernel-stacks index 9a0aa4d3a866..d1bfb0b95ee0 100644 --- a/Documentation/x86/kernel-stacks +++ b/Documentation/x86/kernel-stacks @@ -59,7 +59,7 @@ If that assumption is ever broken then the stacks will become corrupt. The currently assigned IST stacks are :- -* DOUBLEFAULT_STACK. EXCEPTION_STKSZ (PAGE_SIZE). +* ESTACK_DF. EXCEPTION_STKSZ (PAGE_SIZE). Used for interrupt 8 - Double Fault Exception (#DF). @@ -68,7 +68,7 @@ The currently assigned IST stacks are :- Using a separate stack allows the kernel to recover from it well enough in many cases to still output an oops. -* NMI_STACK. EXCEPTION_STKSZ (PAGE_SIZE). +* ESTACK_NMI. EXCEPTION_STKSZ (PAGE_SIZE). Used for non-maskable interrupts (NMI). @@ -76,7 +76,7 @@ The currently assigned IST stacks are :- middle of switching stacks. Using IST for NMI events avoids making assumptions about the previous state of the kernel stack. -* DEBUG_STACK. DEBUG_STKSZ +* ESTACK_DB. EXCEPTION_STKSZ (PAGE_SIZE). Used for hardware debug interrupts (interrupt 1) and for software debug interrupts (INT3). @@ -86,7 +86,12 @@ The currently assigned IST stacks are :- avoids making assumptions about the previous state of the kernel stack. -* MCE_STACK. EXCEPTION_STKSZ (PAGE_SIZE). + To handle nested #DB correctly there exist two instances of DB stacks. On + #DB entry the IST stackpointer for #DB is switched to the second instance + so a nested #DB starts from a clean stack. The nested #DB switches + the IST stackpointer to a guard hole to catch triple nesting. + +* ESTACK_MCE. EXCEPTION_STKSZ (PAGE_SIZE). Used for interrupt 18 - Machine Check Exception (#MC). diff --git a/Documentation/x86/topology.txt b/Documentation/x86/topology.txt index 2953e3ec9a02..06b3cdbc4048 100644 --- a/Documentation/x86/topology.txt +++ b/Documentation/x86/topology.txt @@ -51,7 +51,7 @@ The topology of a system is described in the units of: The physical ID of the package. This information is retrieved via CPUID and deduced from the APIC IDs of the cores in the package. - - cpuinfo_x86.logical_id: + - cpuinfo_x86.logical_proc_id: The logical ID of the package. As we do not trust BIOSes to enumerate the packages in a consistent way, we introduced the concept of logical package diff --git a/Documentation/x86/x86_64/mm.txt b/Documentation/x86/x86_64/mm.txt index 804f9426ed17..6cbe652d7a49 100644 --- a/Documentation/x86/x86_64/mm.txt +++ b/Documentation/x86/x86_64/mm.txt @@ -72,7 +72,7 @@ Complete virtual memory map with 5-level page tables Notes: - With 56-bit addresses, user-space memory gets expanded by a factor of 512x, - from 0.125 PB to 64 PB. All kernel mappings shift down to the -64 PT starting + from 0.125 PB to 64 PB. All kernel mappings shift down to the -64 PB starting offset and many of the regions expand to support the much larger physical memory supported. @@ -83,7 +83,7 @@ Notes: 0000000000000000 | 0 | 00ffffffffffffff | 64 PB | user-space virtual memory, different per mm __________________|____________|__________________|_________|___________________________________________________________ | | | | - 0000800000000000 | +64 PB | ffff7fffffffffff | ~16K PB | ... huge, still almost 64 bits wide hole of non-canonical + 0100000000000000 | +64 PB | feffffffffffffff | ~16K PB | ... huge, still almost 64 bits wide hole of non-canonical | | | | virtual memory addresses up to the -64 PB | | | | starting offset of kernel mappings. __________________|____________|__________________|_________|___________________________________________________________ @@ -99,7 +99,7 @@ ____________________________________________________________|___________________ ffd2000000000000 | -11.5 PB | ffd3ffffffffffff | 0.5 PB | ... unused hole ffd4000000000000 | -11 PB | ffd5ffffffffffff | 0.5 PB | virtual memory map (vmemmap_base) ffd6000000000000 | -10.5 PB | ffdeffffffffffff | 2.25 PB | ... unused hole - ffdf000000000000 | -8.25 PB | fffffdffffffffff | ~8 PB | KASAN shadow memory + ffdf000000000000 | -8.25 PB | fffffbffffffffff | ~8 PB | KASAN shadow memory __________________|____________|__________________|_________|____________________________________________________________ | | Identical layout to the 47-bit one from here on: |