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2021-09-07Merge branch 'cpufreq/arm/linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pmRafael J. Wysocki1-1/+57
Pull more ARM cpufreq changes for v5.15-rc1 from Viresh Kumar: "This adds a new cpufreq driver for Mediatek, which had been going through reviews since last one year." * 'cpufreq/arm/linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm: cpufreq: mediatek-hw: Add support for CPUFREQ HW cpufreq: Add of_perf_domain_get_sharing_cpumask dt-bindings: cpufreq: add bindings for MediaTek cpufreq HW
2021-09-06cpufreq: Add of_perf_domain_get_sharing_cpumaskHector.Yuan1-1/+57
Add of_perf_domain_get_sharing_cpumask function to group cpu to specific performance domain. Signed-off-by: Hector.Yuan <hector.yuan@mediatek.com> [ Viresh: create separate routine parse_perf_domain() and always set the cpumask. ] Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2021-09-02cpufreq: Remove ready() callbackViresh Kumar1-3/+0
This isn't used anymore, get rid of it. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-08-12cpufreq: Add callback to register with energy modelViresh Kumar1-0/+14
Many cpufreq drivers register with the energy model for each policy and do exactly the same thing. Follow the footsteps of thermal-cooling, to get it done from the cpufreq core itself. Provide a new callback, which will be called, if present, by the cpufreq core at the right moment (more on that in the code's comment). Also provide a generic implementation that uses dev_pm_opp_of_register_em(). This also allows us to register with the EM at a later point of time, compared to ->init(), from where the EM core can access cpufreq policy directly using cpufreq_cpu_get() type of helpers and perform other work, like marking few frequencies inefficient, this will be done separately. Reviewed-by: Quentin Perret <qperret@google.com> Reviewed-by: Lukasz Luba <lukasz.luba@arm.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2021-06-30cpufreq: Remove ->resolve_freq()Viresh Kumar1-9/+0
Commit e3c062360870 ("cpufreq: add cpufreq_driver_resolve_freq()") introduced this callback, back in 2016, for drivers that provide the ->target() callback. The kernel hasn't seen a single user of it in the past 5 years and it is not likely to be used any time soon. Remove it for now. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> [ rjw: Changelog edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-06-30cpufreq: Remove the ->stop_cpu() driver callbackViresh Kumar1-1/+0
Now that all users of ->stop_cpu() have been migrated to using other callbacks, drop it from the core. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> [ rjw: Minor edits in the subject and changelog ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-02-04cpufreq: Remove unused flag CPUFREQ_PM_NO_WARNViresh Kumar1-8/+5
This flag is set by one of the drivers but it isn't used in the code otherwise. Remove the unused flag and update the driver. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2021-02-04cpufreq: Remove CPUFREQ_STICKY flagViresh Kumar1-10/+7
During cpufreq driver's registration, if the ->init() callback for all the CPUs fail then there is not much point in keeping the driver around as it will only account for more of unnecessary noise, for example cpufreq core will try to suspend/resume the driver which never got registered properly. The removal of such a driver is avoided if the driver carries the CPUFREQ_STICKY flag. This was added way back [1] in 2004 and perhaps no one should ever need it now. A lot of drivers do set this flag, probably because they just copied it from other drivers. This was added earlier for some platforms [2] because their cpufreq drivers were getting registered before the CPUs were registered with subsys framework. And hence they used to fail. The same isn't true anymore though. The current code flow in the kernel is: start_kernel() -> kernel_init() -> kernel_init_freeable() -> do_basic_setup() -> driver_init() -> cpu_dev_init() -> subsys_system_register() //For CPUs -> do_initcalls() -> cpufreq_register_driver() Clearly, the CPUs will always get registered with subsys framework before any cpufreq driver can get probed. Remove the flag and update the relevant drivers. Link: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git/commit/include/linux/cpufreq.h?id=7cc9f0d9a1ab04cedc60d64fd8dcf7df224a3b4d # [1] Link: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git/commit/arch/arm/mach-sa1100/cpu-sa1100.c?id=f59d3bbe35f6268d729f51be82af8325d62f20f5 # [2] Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-12-15cpufreq: Add special-purpose fast-switching callback for driversRafael J. Wysocki1-0/+14
First off, some cpufreq drivers (eg. intel_pstate) can pass hints beyond the current target frequency to the hardware and there are no provisions for doing that in the cpufreq framework. In particular, today the driver has to assume that it should not allow the frequency to fall below the one requested by the governor (or the required capacity may not be provided) which may not be the case and which may lead to excessive energy usage in some scenarios. Second, the hints passed by these drivers to the hardware need not be in terms of the frequency, so representing the utilization numbers coming from the scheduler as frequency before passing them to those drivers is not really useful. Address the two points above by adding a special-purpose replacement for the ->fast_switch callback, called ->adjust_perf, allowing the governor to pass abstract performance level (rather than frequency) values for the minimum (required) and target (desired) performance along with the CPU capacity to compare them to. Also update the schedutil governor to use the new callback instead of ->fast_switch if present and if the utilization mertics are frequency-invariant (that is requisite for the direct mapping between the utilization and the CPU performance levels to be a reasonable approximation). Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2020-11-16Merge back cpufreq updates for v5.11.Rafael J. Wysocki1-5/+0
2020-11-10cpufreq: Add strict_target to struct cpufreq_policyRafael J. Wysocki1-0/+6
Add a new field to be set when the CPUFREQ_GOV_STRICT_TARGET flag is set for the current governor to struct cpufreq_policy, so that the drivers needing to check CPUFREQ_GOV_STRICT_TARGET do not have to access the governor object during every frequency transition. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2020-11-10cpufreq: Introduce CPUFREQ_GOV_STRICT_TARGETRafael J. Wysocki1-0/+3
Introduce a new governor flag, CPUFREQ_GOV_STRICT_TARGET, for the governors that want the target frequency to be set exactly to the given value without leaving any room for adjustments on the hardware side and set this flag for the powersave and performance governors. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2020-11-10cpufreq: Introduce governor flagsRafael J. Wysocki1-2/+7
A new cpufreq governor flag will be added subsequently, so replace the bool dynamic_switching fleid in struct cpufreq_governor with a flags field and introduce CPUFREQ_GOV_DYNAMIC_SWITCHING to set for the "dynamic switching" governors instead of it. No intentional functional impact. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2020-11-02cpufreq: Drop restore_freq from struct cpufreq_policyRafael J. Wysocki1-5/+0
The restore_freq field in struct cpufreq_policy is only used by __target_index() in one place and a local variable in that function may as well be used instead of it, so drop it and modify __target_index() accordingly. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2020-10-29cpufreq: Introduce cpufreq_driver_test_flags()Rafael J. Wysocki1-0/+1
Add a helper function to test the flags of the cpufreq driver in use againt a given flags mask. In particular, this will be needed to test the CPUFREQ_NEED_UPDATE_LIMITS cpufreq driver flag in the schedutil governor. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-10-27cpufreq: Introduce CPUFREQ_NEED_UPDATE_LIMITS driver flagRafael J. Wysocki1-1/+9
Generally, a cpufreq driver may need to update some internal upper and lower frequency boundaries on policy max and min changes, respectively, but currently this does not work if the target frequency does not change along with the policy limit. Namely, if the target frequency does not change along with the policy min or max, the "target_freq == policy->cur" check in __cpufreq_driver_target() prevents driver callbacks from being invoked and they do not even have a chance to update the corresponding internal boundary. This particularly affects the "powersave" and "performance" governors that always set the target frequency to one of the policy limits and it never changes when the other limit is updated. To allow cpufreq the drivers needing to update internal frequency boundaries on policy limits changes to avoid this issue, introduce a new driver flag, CPUFREQ_NEED_UPDATE_LIMITS, that (when set) will neutralize the check mentioned above. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2020-10-08cpufreq,arm,arm64: restructure definitions of arch_set_freq_scale()Ionela Voinescu1-3/+8
Compared to other arch_* functions, arch_set_freq_scale() has an atypical weak definition that can be replaced by a strong architecture specific implementation. The more typical support for architectural functions involves defining an empty stub in a header file if the symbol is not already defined in architecture code. Some examples involve: - #define arch_scale_freq_capacity topology_get_freq_scale - #define arch_scale_freq_invariant topology_scale_freq_invariant - #define arch_scale_cpu_capacity topology_get_cpu_scale - #define arch_update_cpu_topology topology_update_cpu_topology - #define arch_scale_thermal_pressure topology_get_thermal_pressure - #define arch_set_thermal_pressure topology_set_thermal_pressure Bring arch_set_freq_scale() in line with these functions by renaming it to topology_set_freq_scale() in the arch topology driver, and by defining the arch_set_freq_scale symbol to point to the new function for arm and arm64. While there are other users of the arch_topology driver, this patch defines arch_set_freq_scale for arm and arm64 only, due to their existing definitions of arch_scale_freq_capacity. This is the getter function of the frequency invariance scale factor and without a getter function, the setter function - arch_set_freq_scale() has not purpose. Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Sudeep Holla <sudeep.holla@arm.com> (BL_SWITCHER and topology parts) Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-09-18arch_topology, cpufreq: constify arch_* cpumasksValentin Schneider1-1/+2
The passed cpumask arguments to arch_set_freq_scale() and arch_freq_counters_available() are only iterated over, so reflect this in the prototype. This also allows to pass system cpumasks like cpu_online_mask without getting a warning. Signed-off-by: Valentin Schneider <valentin.schneider@arm.com> Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-09-18cpufreq: report whether cpufreq supports Frequency Invariance (FI)Ionela Voinescu1-0/+5
Now that the update of the FI scale factor is done in cpufreq core for selected functions - target(), target_index() and fast_switch(), we can provide feedback to the task scheduler and architecture code on whether cpufreq supports FI. For this purpose provide an external function to expose whether the cpufreq drivers support FI, by using a static key. The logic behind the enablement of cpufreq-based invariance is as follows: - cpufreq-based invariance is disabled by default - cpufreq-based invariance is enabled if any of the callbacks above is implemented while the unsupported setpolicy() is not The cpufreq_supports_freq_invariance() function only returns whether cpufreq is instrumented with the arch_set_freq_scale() calls that result in support for frequency invariance. Due to the lack of knowledge on whether the implementation of arch_set_freq_scale() actually results in the setting of a scale factor based on cpufreq information, it is up to the architecture code to ensure the setting and provision of the scale factor to the scheduler. Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-08-27cpufreq: Use WARN_ON_ONCE() for invalid relationViresh Kumar1-2/+2
The relation can't be invalid here, so if it turns out to be invalid, just WARN_ON_ONCE() and return 0. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> [ rjw: Subject and changelog edits ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-08-11cpufreq: intel_pstate: Implement passive mode with HWP enabledRafael J. Wysocki1-0/+2
Allow intel_pstate to work in the passive mode with HWP enabled and make it set the HWP minimum performance limit (HWP floor) to the P-state value given by the target frequency supplied by the cpufreq governor, so as to prevent the HWP algorithm and the CPU scheduler from working against each other, at least when the schedutil governor is in use, and update the intel_pstate documentation accordingly. Among other things, this allows utilization clamps to be taken into account, at least to a certain extent, when intel_pstate is in use and makes it more likely that sufficient capacity for deadline tasks will be provided. After this change, the resulting behavior of an HWP system with intel_pstate in the passive mode should be close to the behavior of the analogous non-HWP system with intel_pstate in the passive mode, except that the HWP algorithm is generally allowed to make the CPU run at a frequency above the floor P-state set by intel_pstate in the entire available range of P-states, while without HWP a CPU can run in a P-state above the requested one if the latter falls into the range of turbo P-states (referred to as the turbo range) or if the P-states of all CPUs in one package are coordinated with each other at the hardware level. [Note that in principle the HWP floor may not be taken into account by the processor if it falls into the turbo range, in which case the processor has a license to choose any P-state, either below or above the HWP floor, just like a non-HWP processor in the case when the target P-state falls into the turbo range.] With this change applied, intel_pstate in the passive mode assumes complete control over the HWP request MSR and concurrent changes of that MSR (eg. via the direct MSR access interface) are overridden by it. Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Reviewed-by: Francisco Jerez <currojerez@riseup.net>
2020-08-04Merge branch 'cpufreq/arm/linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pmRafael J. Wysocki1-1/+1
Pull ARM cpufreq driver changes for v5.9-rc1 from Viresh Kumar: "Here are the details: - Adaptive voltage scaling (AVS) support and minor cleanups for brcmstb driver (Florian Fainelli and Markus Mayer). - A new tegra driver and cleanup for the existing one (Sumit Gupta and Jon Hunter). - Bandwidth level support for Qcom driver along with OPP changes (Sibi Sankar). - Cleanups to sti, cpufreq-dt, ap806, CPPC drivers (Viresh Kumar, Lee Jones, Ivan Kokshaysky, Sven Auhagen, and Xin Hao). - Make schedutil default governor for ARM (Valentin Schneider). - Fix dependency issues for imx (Walter Lozano). - Cleanup around cached_resolved_idx in cpufreq core (Viresh Kumar)." * 'cpufreq/arm/linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/vireshk/pm: cpufreq: make schedutil the default for arm and arm64 cpufreq: cached_resolved_idx can not be negative cpufreq: Add Tegra194 cpufreq driver dt-bindings: arm: Add NVIDIA Tegra194 CPU Complex binding cpufreq: imx: Select NVMEM_IMX_OCOTP cpufreq: sti-cpufreq: Fix some formatting and misspelling issues cpufreq: tegra186: Simplify probe return path cpufreq: CPPC: Reuse caps variable in few routines cpufreq: ap806: fix cpufreq driver needs ap cpu clk cpufreq: cppc: Reorder code and remove apply_hisi_workaround variable cpufreq: dt: fix oops on armada37xx cpufreq: brcmstb-avs-cpufreq: send S2_ENTER / S2_EXIT commands to AVS cpufreq: brcmstb-avs-cpufreq: Support polling AVS firmware cpufreq: brcmstb-avs-cpufreq: more flexible interface for __issue_avs_command() cpufreq: qcom: Disable fast switch when scaling DDR/L3 cpufreq: qcom: Update the bandwidth levels on frequency change OPP: Add and export helper to set bandwidth cpufreq: blacklist SC7180 in cpufreq-dt-platdev cpufreq: blacklist SDM845 in cpufreq-dt-platdev
2020-07-30cpufreq: cached_resolved_idx can not be negativeViresh Kumar1-1/+1
It is not possible for cached_resolved_idx to be invalid here as the cpufreq core always sets index to a positive value. Change its type to unsigned int and fix qcom usage a bit. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
2020-07-02cpufreq: Register governors at core_initcallQuentin Perret1-0/+14
Currently, most CPUFreq governors are registered at the core_initcall time when the given governor is the default one, and the module_init time otherwise. In preparation for letting users specify the default governor on the kernel command line, change all of them to be registered at the core_initcall unconditionally, as it is already the case for the schedutil and performance governors. This will allow us to assume that builtin governors have been registered before the built-in CPUFreq drivers probe. And since all governors have similar init/exit patterns now, introduce two new macros, cpufreq_governor_{init,exit}(), to factorize the code. Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Quentin Perret <qperret@google.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> [ rjw: Changelog ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-06-05cpufreq: change '.set_boost' to act on one policyXiongfeng Wang1-1/+1
Macro 'for_each_active_policy()' is defined internally. To avoid some cpufreq driver needing this macro to iterate over all the policies in '.set_boost' callback, we redefine '.set_boost' to act on only one policy and pass the policy as an argument. 'cpufreq_boost_trigger_state()' iterates over all the policies to set boost for the system. This is preparation for adding SW BOOST support for CPPC. To protect Boost enable/disable by sysfs from CPU online/offline, add 'cpu_hotplug_lock' before calling '.set_boost' for each CPU. Also move the lock from 'set_boost()' to 'store_cpb()' in acpi_cpufreq. Signed-off-by: Xiongfeng Wang <wangxiongfeng2@huawei.com> Suggested-by: Viresh Kumar <viresh.kumar@linaro.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> [ rjw: Subject & changelog ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-05-14cpufreq: fix minor typo in struct cpufreq_driver doc commentWang Wenhu1-1/+1
Delete the duplicate "to", possibly double-typed. Signed-off-by: Wang Wenhu <wenhu.wang@vivo.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-03-06cpufreq: add function to get the hardware max frequencyIonela Voinescu1-0/+5
Add weak function to return the hardware maximum frequency of a CPU, with the default implementation returning cpuinfo.max_freq, which is the best information we can generically get from the cpufreq framework. The default can be overwritten by a strong function in platforms that want to provide an alternative implementation, with more accurate information, obtained either from hardware or firmware. Signed-off-by: Ionela Voinescu <ionela.voinescu@arm.com> Reviewed-by: Valentin Schneider <valentin.schneider@arm.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Cc: Viresh Kumar <viresh.kumar@linaro.org> Cc: Rafael J. Wysocki <rjw@rjwysocki.net> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2020-02-03cpufreq: Make cpufreq_global_kobject staticYangtao Li1-3/+0
The cpufreq_global_kobject is only used internally by cpufreq.c after commit 2361be236662 ("cpufreq: Don't create empty /sys/devices/system/cpu/cpufreq directory"). Make it static. Signed-off-by: Yangtao Li <tiny.windzz@gmail.com> [ rjw: Add empty line after cpufreq_global_kobject definition ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2020-01-27cpufreq: Avoid creating excessively large stack framesRafael J. Wysocki1-9/+23
In the process of modifying a cpufreq policy, the cpufreq core makes a copy of it including all of the internals which is stored on the CPU stack. Because struct cpufreq_policy is relatively large, this may cause the size of the stack frame to exceed the 2 KB limit and so the GCC complains when -Wframe-larger-than= is used. In fact, it is not necessary to copy the entire policy structure in order to modify it, however. First, because cpufreq_set_policy() obtains the min and max policy limits from frequency QoS now, it is not necessary to pass the limits to it from the callers. The only things that need to be passed to it from there are the new governor pointer or (if there is a built-in governor in the driver) the "policy" value representing the governor choice. They both can be passed as individual arguments, though, so make cpufreq_set_policy() take them this way and rework its callers accordingly. This avoids making copies of cpufreq policies in the callers of cpufreq_set_policy(). Second, cpufreq_set_policy() still needs to pass the new policy data to the ->verify() callback of the cpufreq driver whose task is to sanitize the min and max policy limits. It still does not need to make a full copy of struct cpufreq_policy for this purpose, but it needs to pass a few items from it to the driver in case they are needed (different drivers have different needs in that respect and all of them have to be covered). For this reason, introduce struct cpufreq_policy_data to hold copies of the members of struct cpufreq_policy used by the existing ->verify() driver callbacks and pass a pointer to a temporary structure of that type to ->verify() (instead of passing a pointer to full struct cpufreq_policy to it). While at it, notice that intel_pstate and longrun don't really need to verify the "policy" value in struct cpufreq_policy, so drop those check from them to avoid copying "policy" into struct cpufreq_policy_data (which allows it to be slightly smaller). Also while at it fix up white space in a couple of places and make cpufreq_set_policy() static (as it can be so). Fixes: 3000ce3c52f8 ("cpufreq: Use per-policy frequency QoS") Link: https://lore.kernel.org/linux-pm/CAMuHMdX6-jb1W8uC2_237m8ctCpsnGp=JCxqt8pCWVqNXHmkVg@mail.gmail.com Reported-by: kbuild test robot <lkp@intel.com> Reported-by: Geert Uytterhoeven <geert@linux-m68k.org> Cc: 5.4+ <stable@vger.kernel.org> # 5.4+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2019-12-12cpufreq: Avoid leaving stale IRQ work items during CPU offlineRafael J. Wysocki1-11/+0
The scheduler code calling cpufreq_update_util() may run during CPU offline on the target CPU after the IRQ work lists have been flushed for it, so the target CPU should be prevented from running code that may queue up an IRQ work item on it at that point. Unfortunately, that may not be the case if dvfs_possible_from_any_cpu is set for at least one cpufreq policy in the system, because that allows the CPU going offline to run the utilization update callback of the cpufreq governor on behalf of another (online) CPU in some cases. If that happens, the cpufreq governor callback may queue up an IRQ work on the CPU running it, which is going offline, and the IRQ work may not be flushed after that point. Moreover, that IRQ work cannot be flushed until the "offlining" CPU goes back online, so if any other CPU calls irq_work_sync() to wait for the completion of that IRQ work, it will have to wait until the "offlining" CPU is back online and that may not happen forever. In particular, a system-wide deadlock may occur during CPU online as a result of that. The failing scenario is as follows. CPU0 is the boot CPU, so it creates a cpufreq policy and becomes the "leader" of it (policy->cpu). It cannot go offline, because it is the boot CPU. Next, other CPUs join the cpufreq policy as they go online and they leave it when they go offline. The last CPU to go offline, say CPU3, may queue up an IRQ work while running the governor callback on behalf of CPU0 after leaving the cpufreq policy because of the dvfs_possible_from_any_cpu effect described above. Then, CPU0 is the only online CPU in the system and the stale IRQ work is still queued on CPU3. When, say, CPU1 goes back online, it will run irq_work_sync() to wait for that IRQ work to complete and so it will wait for CPU3 to go back online (which may never happen even in principle), but (worse yet) CPU0 is waiting for CPU1 at that point too and a system-wide deadlock occurs. To address this problem notice that CPUs which cannot run cpufreq utilization update code for themselves (for example, because they have left the cpufreq policies that they belonged to), should also be prevented from running that code on behalf of the other CPUs that belong to a cpufreq policy with dvfs_possible_from_any_cpu set and so in that case the cpufreq_update_util_data pointer of the CPU running the code must not be NULL as well as for the CPU which is the target of the cpufreq utilization update in progress. Accordingly, change cpufreq_this_cpu_can_update() into a regular function in kernel/sched/cpufreq.c (instead of a static inline in a header file) and make it check the cpufreq_update_util_data pointer of the local CPU if dvfs_possible_from_any_cpu is set for the target cpufreq policy. Also update the schedutil governor to do the cpufreq_this_cpu_can_update() check in the non-fast-switch case too to avoid the stale IRQ work issues. Fixes: 99d14d0e16fa ("cpufreq: Process remote callbacks from any CPU if the platform permits") Link: https://lore.kernel.org/linux-pm/20191121093557.bycvdo4xyinbc5cb@vireshk-i7/ Reported-by: Anson Huang <anson.huang@nxp.com> Tested-by: Anson Huang <anson.huang@nxp.com> Cc: 4.14+ <stable@vger.kernel.org> # 4.14+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Tested-by: Peng Fan <peng.fan@nxp.com> (i.MX8QXP-MEK) Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-10-21cpufreq: Use per-policy frequency QoSRafael J. Wysocki1-2/+5
Replace the CPU device PM QoS used for the management of min and max frequency constraints in cpufreq (and its users) with per-policy frequency QoS to avoid problems with cpufreq policies covering more then one CPU. Namely, a cpufreq driver is registered with the subsys interface which calls cpufreq_add_dev() for each CPU, starting from CPU0, so currently the PM QoS notifiers are added to the first CPU in the policy (i.e. CPU0 in the majority of cases). In turn, when the cpufreq driver is unregistered, the subsys interface doing that calls cpufreq_remove_dev() for each CPU, starting from CPU0, and the PM QoS notifiers are only removed when cpufreq_remove_dev() is called for the last CPU in the policy, say CPUx, which as a rule is not CPU0 if the policy covers more than one CPU. Then, the PM QoS notifiers cannot be removed, because CPUx does not have them, and they are still there in the device PM QoS notifiers list of CPU0, which prevents new PM QoS notifiers from being registered for CPU0 on the next attempt to register the cpufreq driver. The same issue occurs when the first CPU in the policy goes offline before unregistering the driver. After this change it does not matter which CPU is the policy CPU at the driver registration time and whether or not it is online all the time, because the frequency QoS is per policy and not per CPU. Fixes: 67d874c3b2c6 ("cpufreq: Register notifiers with the PM QoS framework") Reported-by: Dmitry Osipenko <digetx@gmail.com> Tested-by: Dmitry Osipenko <digetx@gmail.com> Reported-by: Sudeep Holla <sudeep.holla@arm.com> Tested-by: Sudeep Holla <sudeep.holla@arm.com> Diagnosed-by: Viresh Kumar <viresh.kumar@linaro.org> Link: https://lore.kernel.org/linux-pm/5ad2624194baa2f53acc1f1e627eb7684c577a19.1562210705.git.viresh.kumar@linaro.org/T/#md2d89e95906b8c91c15f582146173dce2e86e99f Link: https://lore.kernel.org/linux-pm/20191017094612.6tbkwoq4harsjcqv@vireshk-i7/T/#m30d48cc23b9a80467fbaa16e30f90b3828a5a29b Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2019-09-02cpufreq: Remove CPUFREQ_ADJUST and CPUFREQ_NOTIFY policy notifier eventsViresh Kumar1-4/+2
No driver makes reference to these events now, remove them and the code related to them. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-08-10cpufreq: Add policy create/remove notifiers backViresh Kumar1-0/+2
This effectively reverts some changes made by commit f9f41e3ef99 ("cpufreq: Remove policy create/remove notifiers"). We have a new use case for policy create/remove notifiers (for allocating/freeing QoS requests per policy), so add them back. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> [ rjw: Subject & changelog ] Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-07-18Merge branch 'pm-cpufreq'Rafael J. Wysocki1-7/+7
* pm-cpufreq: cpufreq: Make cpufreq_generic_init() return void cpufreq: imx-cpufreq-dt: Add i.MX8MN support cpufreq: Add QoS requests for userspace constraints cpufreq: intel_pstate: Reuse refresh_frequency_limits() cpufreq: Register notifiers with the PM QoS framework PM / QoS: Add support for MIN/MAX frequency constraints PM / QOS: Pass request type to dev_pm_qos_read_value() PM / QOS: Rename __dev_pm_qos_read_value() and dev_pm_qos_raw_read_value() PM / QOS: Pass request type to dev_pm_qos_{add|remove}_notifier()
2019-07-16cpufreq: Make cpufreq_generic_init() return voidViresh Kumar1-1/+1
It always returns 0 (success) and its return type should really be void. Over that, many drivers have added error handling code based on its return value, which is not required at all. Change its return type to void and update all the callers. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-07-08cpufreq: Add QoS requests for userspace constraintsViresh Kumar1-6/+2
This implements QoS requests to manage userspace configuration of min and max frequency. Reviewed-by: Matthias Kaehlcke <mka@chromium.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Tested-by: syzbot <syzbot+de771ae9390dffed7266@syzkaller.appspotmail.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-07-08cpufreq: intel_pstate: Reuse refresh_frequency_limits()Viresh Kumar1-0/+1
The implementation of intel_pstate_update_max_freq() is quite similar to refresh_frequency_limits(), lets reuse it. Finding minimum of policy->user_policy.max and policy->cpuinfo.max_freq in intel_pstate_update_max_freq() is redundant as cpufreq_set_policy() will call the ->verify() callback of intel-pstate driver, which will do this comparison anyway and so dropping it from intel_pstate_update_max_freq() doesn't harm. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-07-08cpufreq: Register notifiers with the PM QoS frameworkViresh Kumar1-0/+3
Register notifiers for min/max frequency constraints with the PM QoS framework. The constraints are also taken into consideration in cpufreq_set_policy(). This also relocates cpufreq_policy_put_kobj() as it is required to be called from cpufreq_policy_alloc() now. refresh_frequency_limits() is updated to avoid calling cpufreq_set_policy() for inactive policies and handle_update() is updated to have proper locking in place. No constraints are added until now though. Reviewed-by: Matthias Kaehlcke <mka@chromium.org> Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Tested-by: Pavel Machek <pavel@ucw.cz> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-07-08Merge branch 'pm-cpufreq'Rafael J. Wysocki1-0/+6
* pm-cpufreq: cpufreq: Avoid calling cpufreq_verify_current_freq() from handle_update() cpufreq: Consolidate cpufreq_update_current_freq() and __cpufreq_get() cpufreq: Don't skip frequency validation for has_target() drivers cpufreq: Use has_target() instead of !setpolicy cpufreq: Remove redundant !setpolicy check cpufreq: Move the IS_ENABLED(CPU_THERMAL) macro into a stub cpufreq: s5pv210: Don't flood kernel log after cpufreq change cpufreq: pcc-cpufreq: Fail initialization if driver cannot be registered cpufreq: add driver for Raspberry Pi cpufreq: Switch imx7d to imx-cpufreq-dt for speed grading cpufreq: imx-cpufreq-dt: Remove global platform match list cpufreq: brcmstb-avs-cpufreq: Fix types for voltage/frequency cpufreq: brcmstb-avs-cpufreq: Fix initial command check cpufreq: armada-37xx: Remove set but not used variable 'freq' cpufreq: imx-cpufreq-dt: Fix no OPPs available on unfused parts dt-bindings: imx-cpufreq-dt: Document opp-supported-hw usage cpufreq: Add imx-cpufreq-dt driver
2019-06-26cpufreq: Move the IS_ENABLED(CPU_THERMAL) macro into a stubDaniel Lezcano1-0/+6
cpufreq_online() and cpufreq_offline() [un]register the driver as a cooling device. This is done if the driver is flagged as a cooling device in addition with an IS_ENABLED() check to compile out the branching code. Group this test in a stub function added in the cpufreq header instead of having the IS_ENABLED() in the code. Suggested-by: Rafael J. Wysocki <rafael@kernel.org> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner1-4/+1
Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Enrico Weigelt <info@metux.net> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-10cpufreq: Call transition notifier only once for each policyViresh Kumar1-7/+7
Currently, the notifiers are called once for each CPU of the policy->cpus cpumask. It would be more optimal if the notifier can be called only once and all the relevant information be provided to it. Out of the 23 drivers that register for the transition notifiers today, only 4 of them do per-cpu updates and the callback for the rest can be called only once for the policy without any impact. This would also avoid multiple function calls to the notifier callbacks and reduce multiple iterations of notifier core's code (which does locking as well). This patch adds pointer to the cpufreq policy to the struct cpufreq_freqs, so the notifier callback has all the information available to it with a single call. The five drivers which perform per-cpu updates are updated to use the cpufreq policy. The freqs->cpu field is redundant now and is removed. Acked-by: David S. Miller <davem@davemloft.net> (sparc) Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-04-08cpufreq: intel_pstate: Update max frequency on global turbo changesRafael J. Wysocki1-0/+10
While the cpuinfo.max_freq value doesn't really matter for intel_pstate in the active mode, in the passive mode it is used by governors as the maximum physical frequency of the CPU and the results of governor computations generally depend on it. Also it is made available to user space via sysfs and it should match the current HW configuration. For this reason, make intel_pstate update cpuinfo.max_freq for all CPUs if it detects a global change of turbo frequency settings from "disable" to "enable" or the other way associated with a _PPC change notification from the platform firmware. Note that policy_is_inactive(), cpufreq_cpu_acquire(), cpufreq_cpu_release(), and cpufreq_set_policy() need to be made available to it for this purpose. Link: https://bugzilla.kernel.org/show_bug.cgi?id=200759 Reported-by: Gabriele Mazzotta <gabriele.mzt@gmail.com> Tested-by: Gabriele Mazzotta <gabriele.mzt@gmail.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2019-04-01cpufreq: intel_pstate: Driver-specific handling of _PPC updatesRafael J. Wysocki1-0/+4
In some cases, the platform firmware disables or enables turbo frequencies for all CPUs globally before triggering a _PPC change notification for one of them. Obviously, that global change affects all CPUs, not just the notified one, and it needs to be acted upon by cpufreq. The intel_pstate driver is able to detect such global changes of the settings, but it also needs to update policy limits for all CPUs if that happens, in particular if turbo frequencies are enabled globally - to allow them to be used. For this reason, introduce a new cpufreq driver callback to be invoked on _PPC notifications, if present, instead of simply calling cpufreq_update_policy() for the notified CPU and make intel_pstate use it to trigger policy updates for all CPUs in the system if global settings change. Link: https://bugzilla.kernel.org/show_bug.cgi?id=200759 Reported-by: Gabriele Mazzotta <gabriele.mzt@gmail.com> Tested-by: Gabriele Mazzotta <gabriele.mzt@gmail.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
2019-02-12cpufreq: Allow light-weight tear down and bring up of CPUsViresh Kumar1-0/+2
The cpufreq core doesn't remove the cpufreq policy anymore on CPU offline operation, rather that happens when the CPU device gets unregistered from the kernel. This allows faster recovery when the CPU comes back online. This is also very useful during system wide suspend/resume where we offline all non-boot CPUs during suspend and then bring them back on resume. This commit takes the same idea a step ahead to allow drivers to do light weight tear-down and bring-up during CPU offline and online operations. A new set of callbacks is introduced, online/offline(). online() gets called when the first CPU of an inactive policy is brought up and offline() gets called when all the CPUs of a policy are offlined. The existing init/exit() callback get called on policy creation/destruction. They also get called instead of online/offline() callbacks if the online/offline() callbacks aren't provided. This also moves around some code to get executed only for the new-policy case going forward. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-01-30cpufreq: Auto-register the driver as a thermal cooling device if askedAmit Kucheria1-0/+9
All cpufreq drivers do similar things to register as a cooling device. Provide a cpufreq driver flag so drivers can just ask the cpufreq core to register the cooling device on their behalf. This allows us to get rid of duplicated code in the drivers. In order to allow this, we add a struct thermal_cooling_device pointer to struct cpufreq_policy so that drivers don't need to store it in a private data structure. Suggested-by: Stephen Boyd <swboyd@chromium.org> Suggested-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Amit Kucheria <amit.kucheria@linaro.org> Reviewed-by: Matthias Kaehlcke <mka@chromium.org> Tested-by: Matthias Kaehlcke <mka@chromium.org> Acked-by: Viresh Kumar <viresh.kumar@linaro.org> Reviewed-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-01-29cpufreq: Use struct kobj_attribute instead of struct global_attrViresh Kumar1-10/+2
The cpufreq_global_kobject is created using kobject_create_and_add() helper, which assigns the kobj_type as dynamic_kobj_ktype and show/store routines are set to kobj_attr_show() and kobj_attr_store(). These routines pass struct kobj_attribute as an argument to the show/store callbacks. But all the cpufreq files created using the cpufreq_global_kobject expect the argument to be of type struct attribute. Things work fine currently as no one accesses the "attr" argument. We may not see issues even if the argument is used, as struct kobj_attribute has struct attribute as its first element and so they will both get same address. But this is logically incorrect and we should rather use struct kobj_attribute instead of struct global_attr in the cpufreq core and drivers and the show/store callbacks should take struct kobj_attribute as argument instead. This bug is caught using CFI CLANG builds in android kernel which catches mismatch in function prototypes for such callbacks. Reported-by: Donghee Han <dh.han@samsung.com> Reported-by: Sangkyu Kim <skwith.kim@samsung.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2019-01-21cpufreq: Replace open-coded << with BIT()Amit Kucheria1-12/+13
Minor clean-up to use BIT() and keep checkpatch happy. Clean up the comment formatting while we're at it to make it easier to read. Signed-off-by: Amit Kucheria <amit.kucheria@linaro.org> Reviewed-by: Stephen Boyd <swboyd@chromium.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-12-11sched/topology: Make Energy Aware Scheduling depend on schedutilQuentin Perret1-0/+8
Energy Aware Scheduling (EAS) is designed with the assumption that frequencies of CPUs follow their utilization value. When using a CPUFreq governor other than schedutil, the chances of this assumption being true are small, if any. When schedutil is being used, EAS' predictions are at least consistent with the frequency requests. Although those requests have no guarantees to be honored by the hardware, they should at least guide DVFS in the right direction and provide some hope in regards to the EAS model being accurate. To make sure EAS is only used in a sane configuration, create a strong dependency on schedutil being used. Since having sugov compiled-in does not provide that guarantee, make CPUFreq call a scheduler function on governor changes hence letting it rebuild the scheduling domains, check the governors of the online CPUs, and enable/disable EAS accordingly. Signed-off-by: Quentin Perret <quentin.perret@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rafael J. Wysocki <rjw@rjwysocki.net> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: adharmap@codeaurora.org Cc: chris.redpath@arm.com Cc: currojerez@riseup.net Cc: dietmar.eggemann@arm.com Cc: edubezval@gmail.com Cc: gregkh@linuxfoundation.org Cc: javi.merino@kernel.org Cc: joel@joelfernandes.org Cc: juri.lelli@redhat.com Cc: morten.rasmussen@arm.com Cc: patrick.bellasi@arm.com Cc: pkondeti@codeaurora.org Cc: skannan@codeaurora.org Cc: smuckle@google.com Cc: srinivas.pandruvada@linux.intel.com Cc: thara.gopinath@linaro.org Cc: tkjos@google.com Cc: valentin.schneider@arm.com Cc: vincent.guittot@linaro.org Cc: viresh.kumar@linaro.org Link: https://lkml.kernel.org/r/20181203095628.11858-9-quentin.perret@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2018-05-23cpufreq: Rename cpufreq_can_do_remote_dvfs()Viresh Kumar1-1/+1
This routine checks if the CPU running this code belongs to the policy of the target CPU or if not, can it do remote DVFS for it remotely. But the current name of it implies as if it is only about doing remote updates. Rename it to make it more relevant. Suggested-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>