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2018-11-30Merge tag 'trace-v4.20-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-traceLinus Torvalds1-12/+2
Pull tracing fixes from Steven Rostedt: "While rewriting the function graph tracer, I discovered a design flaw that was introduced by a patch that tried to fix one bug, but by doing so created another bug. As both bugs corrupt the output (but they do not crash the kernel), I decided to fix the design such that it could have both bugs fixed. The original fix, fixed time reporting of the function graph tracer when doing a max_depth of one. This was code that can test how much the kernel interferes with userspace. But in doing so, it could corrupt the time keeping of the function profiler. The issue is that the curr_ret_stack variable was being used for two different meanings. One was to keep track of the stack pointer on the ret_stack (shadow stack used by the function graph tracer), and the other use case was the graph call depth. Although, the two may be closely related, where they got updated was the issue that lead to the two different bugs that required the two use cases to be updated differently. The big issue with this fix is that it requires changing each architecture. The good news is, I was able to remove a lot of code that was duplicated within the architectures and place it into a single location. Then I could make the fix in one place. I pushed this code into linux-next to let it settle over a week, and before doing so, I cross compiled all the affected architectures to make sure that they built fine. In the mean time, I also pulled in a patch that fixes the sched_switch previous tasks state output, that was not actually correct" * tag 'trace-v4.20-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: sched, trace: Fix prev_state output in sched_switch tracepoint function_graph: Have profiler use curr_ret_stack and not depth function_graph: Reverse the order of pushing the ret_stack and the callback function_graph: Move return callback before update of curr_ret_stack function_graph: Use new curr_ret_depth to manage depth instead of curr_ret_stack function_graph: Make ftrace_push_return_trace() static sparc/function_graph: Simplify with function_graph_enter() sh/function_graph: Simplify with function_graph_enter() s390/function_graph: Simplify with function_graph_enter() riscv/function_graph: Simplify with function_graph_enter() powerpc/function_graph: Simplify with function_graph_enter() parisc: function_graph: Simplify with function_graph_enter() nds32: function_graph: Simplify with function_graph_enter() MIPS: function_graph: Simplify with function_graph_enter() microblaze: function_graph: Simplify with function_graph_enter() arm64: function_graph: Simplify with function_graph_enter() ARM: function_graph: Simplify with function_graph_enter() x86/function_graph: Simplify with function_graph_enter() function_graph: Create function_graph_enter() to consolidate architecture code
2018-11-27riscv/function_graph: Simplify with function_graph_enter()Steven Rostedt (VMware)1-12/+2
The function_graph_enter() function does the work of calling the function graph hook function and the management of the shadow stack, simplifying the work done in the architecture dependent prepare_ftrace_return(). Have riscv use the new code, and remove the shadow stack management as well as having to set up the trace structure. This is needed to prepare for a fix of a design bug on how the curr_ret_stack is used. Cc: Greentime Hu <greentime@andestech.com> Cc: Alan Kao <alankao@andestech.com> Cc: stable@kernel.org Fixes: 03274a3ffb449 ("tracing/fgraph: Adjust fgraph depth before calling trace return callback") Reviewed-by: Palmer Dabbelt <palmer@sifive.com> Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-11-20RISC-V: recognize S/U mode bits in print_isaPatrick Stählin1-3/+6
Removes the warning about an unsupported ISA when reading /proc/cpuinfo on QEMU. The "S" extension is not being returned as it is not accessible from userspace. Signed-off-by: Patrick Stählin <me@packi.ch> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-11-20RISC-V: Build flat and compressed kernel imagesAnup Patel2-1/+11
This patch extends Linux RISC-V build system to build and install: Image - Flat uncompressed kernel image Image.gz - Flat and GZip compressed kernel image Quiet a few bootloaders (such as Uboot, UEFI, etc) are capable of booting flat and compressed kernel images. In case of Uboot, booting Image or Image.gz is achieved using bootm command. The flat and uncompressed kernel image (i.e. Image) is very useful in pre-silicon developent and testing because we can create back-door HEX files for RAM on FPGAs from Image. Signed-off-by: Anup Patel <anup@brainfault.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-11-12RISC-V: Silence some module warnings on 32-bitOlof Johansson1-6/+6
Fixes: arch/riscv/kernel/module.c: In function 'apply_r_riscv_32_rela': ./include/linux/kern_levels.h:5:18: warning: format '%llx' expects argument of type 'long long unsigned int', but argument 3 has type 'Elf32_Addr' {aka 'unsigned int'} [-Wformat=] arch/riscv/kernel/module.c:23:27: note: format string is defined here arch/riscv/kernel/module.c: In function 'apply_r_riscv_pcrel_hi20_rela': ./include/linux/kern_levels.h:5:18: warning: format '%llx' expects argument of type 'long long unsigned int', but argument 3 has type 'Elf32_Addr' {aka 'unsigned int'} [-Wformat=] arch/riscv/kernel/module.c:104:23: note: format string is defined here arch/riscv/kernel/module.c: In function 'apply_r_riscv_hi20_rela': ./include/linux/kern_levels.h:5:18: warning: format '%llx' expects argument of type 'long long unsigned int', but argument 3 has type 'Elf32_Addr' {aka 'unsigned int'} [-Wformat=] arch/riscv/kernel/module.c:146:23: note: format string is defined here arch/riscv/kernel/module.c: In function 'apply_r_riscv_got_hi20_rela': ./include/linux/kern_levels.h:5:18: warning: format '%llx' expects argument of type 'long long unsigned int', but argument 3 has type 'Elf32_Addr' {aka 'unsigned int'} [-Wformat=] arch/riscv/kernel/module.c:190:60: note: format string is defined here arch/riscv/kernel/module.c: In function 'apply_r_riscv_call_plt_rela': ./include/linux/kern_levels.h:5:18: warning: format '%llx' expects argument of type 'long long unsigned int', but argument 3 has type 'Elf32_Addr' {aka 'unsigned int'} [-Wformat=] arch/riscv/kernel/module.c:214:24: note: format string is defined here arch/riscv/kernel/module.c: In function 'apply_r_riscv_call_rela': ./include/linux/kern_levels.h:5:18: warning: format '%llx' expects argument of type 'long long unsigned int', but argument 3 has type 'Elf32_Addr' {aka 'unsigned int'} [-Wformat=] arch/riscv/kernel/module.c:236:23: note: format string is defined here Signed-off-by: Olof Johansson <olof@lixom.net> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-31RISC-V: properly determine hardware capsAndreas Schwab1-3/+5
On the Hifive-U platform, cpu 0 is a masked cpu with less capabilities than the other cpus. Ignore it for the purpose of determining the hardware capabilities of the system. Signed-off-by: Andreas Schwab <schwab@suse.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22RISC-V: SMP cleanup and new featuresPalmer Dabbelt7-47/+195
This patch series now has evolved to contain several related changes. 1. Updated the assorted cleanup series by Palmer. The original cleanup patch series can be found here. http://lists.infradead.org/pipermail/linux-riscv/2018-August/001232.html 2. Implemented decoupling linux logical CPU ids from hart id. Some of the work has been inspired from ARM64. Tested on QEMU & HighFive Unleashed board with/without SMP enabled. 3. Included Anup's cleanup and IPI stat patch. All the patch series have been combined to avoid conflicts as a lot of common code is changed different patch sets. Atish has mostly addressed review comments and fixed checkpatch errors from Palmer's and Anup's series. Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22RISC-V: Fix some RV32 bugs and build failuresPalmer Dabbelt1-0/+3
This patch set fixes up various failures in the RV32I port. The fixes are all nominally independent, but are really only testable together because the RV32I port fails to build without all of them. The patch set includes: * The removal of tishift on RV32I targets, as 128-bit integers are not supported by the toolchain. * The removal of swiotlb from RV32I targets, since all physical addresses can be mapped by all hardware on all existing RV32I targets. * The addition of ummodi3 and udivmoddi4 from an old version of GCC that was licensed under GPLv2 as generic code, along with their use on RV32I targets. * A fix to our page alignment logic within ioremap for RV32I targets. Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22riscv: Add support to no-FPU systemsPalmer Dabbelt6-115/+168
This patchset adds an option, CONFIG_FPU, to enable/disable floating- point support within the kernel. The kernel's new behavior will be as follows: * with CONFIG_FPU=y All FPU codes are reserved. If no FPU is found during booting, a global flag will be set, and those functions will be bypassed with condition check to that flag. * with CONFIG_FPU=n No floating-point instructions in kernel and all related settings are excluded. Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22RISC-V: remove the unused return_to_handler exportChristoph Hellwig1-1/+0
This export is not only not needed, but also breaks symbol versioning due to being an undeclared assembly export. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22RISC-V: Add FP register ptrace support for gdb.Jim Wilson1-0/+52
Add a variable and a macro to describe FP registers, assuming only D is supported. FP code is conditional on CONFIG_FPU. The FP regs and FCSR are copied separately to avoid copying struct padding. Tested by hand and with the gdb testsuite. Signed-off-by: Jim Wilson <jimw@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22RISC-V: Mask out the F extension on systems without DPalmer Dabbelt1-0/+7
The RISC-V Linux port doesn't support systems that have the F extension but don't have the D extension -- we actually don't support systems without D either, but Alan's patch set is rectifying that soon. For now I think we can leave this in a semi-broken state and just wait for Alan's patch set to get merged for proper non-FPU support -- the patch set is starting to look good, so doing something in-between doesn't seem like it's worth the work. I don't think it's worth fretting about support for systems with F but not D for now: our glibc ABIs are IMAC and IMAFDC so they probably won't end up being popular. We can always extend this in the future. CC: Alan Kao <alankao@andestech.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22RISC-V: Don't set cacheinfo.{physical_line_partition,attributes}Palmer Dabbelt1-7/+0
These are just hard coded in the RISC-V port, which doesn't make any sense. We should probably be setting these from device tree entries when they exist, but for now I think it's saner to just leave them all as their default values. Reviewed-by: Jeremy Linton <jeremy.linton@arm.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22RISC-V: Show IPI statsAnup Patel2-7/+40
This patch provides arch_show_interrupts() implementation to show IPI stats via /proc/interrupts. Now the contents of /proc/interrupts" will look like below: CPU0 CPU1 CPU2 CPU3 8: 17 7 6 14 SiFive PLIC 8 virtio0 10: 10 10 9 11 SiFive PLIC 10 ttyS0 IPI0: 170 673 251 79 Rescheduling interrupts IPI1: 1 12 27 1 Function call interrupts Signed-off-by: Anup Patel <anup@brainfault.org> [Atish - Fixed checkpatch errors] Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Palmer Dabbelt <palmer@sifive.com> Changes since v2: - Remove use of IPI_CALL_WAKEUP because it's being removed Changes since v1: - Add stub inline show_ipi_stats() function for !CONFIG_SMP - Make ipi_names[] dynamically sized at compile time - Minor beautification of ipi_names[] using tabs Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22RISC-V: Show CPU ID and Hart ID separately in /proc/cpuinfoAnup Patel1-4/+6
Currently, /proc/cpuinfo show logical CPU ID as Hart ID which is in-correct. This patch shows CPU ID and Hart ID separately in /proc/cpuinfo using cpuid_to_hardid_map(). With this patch, contents of /proc/cpuinfo looks as follows: processor : 0 hart : 1 isa : rv64imafdc mmu : sv48 processor : 1 hart : 0 isa : rv64imafdc mmu : sv48 processor : 2 hart : 2 isa : rv64imafdc mmu : sv48 processor : 3 hart : 3 isa : rv64imafdc mmu : sv48 Signed-off-by: Anup Patel <anup@brainfault.org> Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22RISC-V: Use Linux logical CPU number instead of hartidAtish Patra5-22/+45
Setup the cpu_logical_map during boot. Moreover, every SBI call and PLIC context are based on the physical hartid. Use the logical CPU to hartid mapping to pass correct hartid to respective functions. Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Anup Patel <anup@brainfault.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22RISC-V: Add logical CPU indexing for RISC-VAtish Patra2-0/+23
Currently, both Linux CPU id and hart id are same. This is not recommended as it will lead to discontinuous CPU indexing in Linux. Moreover, kdump kernel will run from CPU0 which would be absent if we follow existing scheme. Implement a logical mapping between Linux CPU id and hart id to decouple these two. Always mark the boot processor as CPU0 and all other CPUs get the logical CPU id based on their booting order. Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Anup Patel <anup@brainfault.org> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22RISC-V: Use WRITE_ONCE instead of direct accessAtish Patra1-2/+3
The secondary harts spin on couple of per cpu variables until both of these are non-zero so it's not necessary to have any ordering here. However, WRITE_ONCE should be used to avoid tearing. Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22RISC-V: Use mmgrab()Palmer Dabbelt1-1/+2
commit f1f1007644ff ("mm: add new mmgrab() helper") added a helper that we missed out on. Signed-off-by: Palmer Dabbelt <palmer@sifive.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22RISC-V: Rename im_okay_therefore_i_am to found_boot_cpuPalmer Dabbelt1-4/+5
The old name was a bit odd. Signed-off-by: Palmer Dabbelt <palmer@sifive.com> Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22RISC-V: Rename riscv_of_processor_hart to riscv_of_processor_hartidPalmer Dabbelt2-3/+6
It's a bit confusing exactly what this function does: it actually returns the hartid of an OF processor node, failing with -1 on invalid nodes. I've changed the name to _hartid() in order to make that a bit more clear, as well as adding a comment. Signed-off-by: Palmer Dabbelt <palmer@sifive.com> [Atish: code comment formatting update] Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22RISC-V: Disable preemption before enabling interruptsAtish Patra1-1/+5
Currently, irq is enabled before preemption disabling happens. If the scheduler fired right here and cpu is scheduled then it may blow up. Signed-off-by: Palmer Dabbelt <palmer@sifive.com> [Atish: Commit text and code comment formatting update] Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22RISC-V: Comment on the TLB flush in smp_callin()Palmer Dabbelt1-0/+4
This isn't readily apparent from reading the code. Signed-off-by: Palmer Dabbelt <palmer@sifive.com> [Atish: code comment formatting update] Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22RISC-V: Filter ISA and MMU values in cpuinfoPalmer Dabbelt1-7/+61
We shouldn't be directly passing device tree values to userspace, both because there could be mistakes in device trees and because the kernel doesn't support arbitrary ISAs. Signed-off-by: Palmer Dabbelt <palmer@sifive.com> [Atish: checkpatch fix and code comment formatting update] Signed-off-by: Atish Patra <atish.patra@wdc.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22RISC-V: Don't set cacheinfo.{physical_line_partition,attributes}Palmer Dabbelt1-7/+0
These are just hard coded in the RISC-V port, which doesn't make any sense. We should probably be setting these from device tree entries when they exist, but for now I think it's saner to just leave them all as their default values. Signed-off-by: Palmer Dabbelt <palmer@sifive.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Reviewed-by: Jeremy Linton <jeremy.linton@arm.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22RISC-V: No need to pass scause as arg to do_IRQ()Anup Patel2-3/+2
The scause is already part of pt_regs so no need to pass scause as separate arg to do_IRQ(). Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Anup Patel <anup@brainfault.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22RISC-V: Use swiotlb on RV64 onlyZong Li1-0/+3
Only RV64 supports swiotlb. On RV32, it don't select the SWIOTLB. Signed-off-by: Zong Li <zong@andestech.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22Auto-detect whether a FPU existsAlan Kao3-3/+15
We expect that a kernel with CONFIG_FPU=y can still support no-FPU machines. To do so, the kernel should first examine the existence of a FPU, then do nothing if a FPU does exist; otherwise, it should disable/bypass all FPU-related functions. In this patch, a new global variable, has_fpu, is created and determined when parsing the hardware capability from device tree during booting. This variable is used in those FPU-related functions. Signed-off-by: Alan Kao <alankao@andestech.com> Cc: Greentime Hu <greentime@andestech.com> Cc: Vincent Chen <vincentc@andestech.com> Cc: Zong Li <zong@andestech.com> Cc: Nick Hu <nickhu@andestech.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22Allow to disable FPU supportAlan Kao3-2/+9
FPU codes have been separated from common part in previous patches. This patch add the CONFIG_FPU option and some stubs, so that a no-FPU configuration is allowed. Signed-off-by: Alan Kao <alankao@andestech.com> Cc: Greentime Hu <greentime@andestech.com> Cc: Vincent Chen <vincentc@andestech.com> Cc: Zong Li <zong@andestech.com> Cc: Nick Hu <nickhu@andestech.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22Refactor FPU code in signal setup/return proceduresAlan Kao1-27/+41
FPU-related logic is separated from normal signal handling path in this patch. Kernel can easily be configured to exclude those procedures for no-FPU systems. Signed-off-by: Alan Kao <alankao@andestech.com> Cc: Greentime Hu <greentime@andestech.com> Cc: Vincent Chen <vincentc@andestech.com> Cc: Zong Li <zong@andestech.com> Cc: Nick Hu <nickhu@andestech.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-22Extract FPU context operations from entry.SAlan Kao3-87/+107
We move __fstate_save and __fstate_restore to a new source file, fpu.S. Signed-off-by: Alan Kao <alankao@andestech.com> Cc: Greentime Hu <greentime@andestech.com> Cc: Vincent Chen <vincentc@andestech.com> Cc: Zong Li <zong@andestech.com> Cc: Nick Hu <nickhu@andestech.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-10-02RISCV: Fix end PFN for low memoryAtish Patra1-1/+1
Use memblock_end_of_DRAM which provides correct last low memory PFN. Without that, DMA32 region becomes empty resulting in zero pages being allocated for DMA32. This patch is based on earlier patch from palmer which never merged into 4.19. I just edited the commit text to make more sense. Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-09-04riscv: Do not overwrite initrd_start and initrd_endGuenter Roeck1-7/+0
setup_initrd() overwrites initrd_start and initrd_end if __initramfs_size is larger than 0, which is always true even if there is no embedded initramfs. This prevents booting qemu with "-initrd" parameter. Overwriting initrd_start and initrd_end is not necessary since __initramfs_start and __initramfs_size are used directly in populate_rootfs() to load the built-in initramfs, so just drop that code. Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-08-28RISC-V: Use a less ugly workaround for unused variable warningsPalmer Dabbelt1-14/+1
Thanks to Christoph Hellwig for pointing out a cleaner way to do this, as my approach was quite ugly. CC: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-08-20RISC-V: Define sys_riscv_flush_icache when SMP=nPalmer Dabbelt1-2/+10
This would be necessary to make non-SMP builds work, but there is another error in the implementation of our syscall linkage that actually just causes sys_riscv_flush_icache to never build. I've build tested this on allnoconfig and allnoconfig+SMP=y, as well as defconfig like normal. CC: Christoph Hellwig <hch@infradead.org> CC: Guenter Roeck <linux@roeck-us.net> In-Reply-To: <20180809055830.GA17533@infradead.org> In-Reply-To: <20180809132612.GA31058@roeck-us.net> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-08-13RISC-V: Fix !CONFIG_SMP compilation errorAtish Patra1-1/+0
Enabling both CONFIG_PERF_EVENTS without !CONFIG_SMP generates following compilation error. arch/riscv/include/asm/perf_event.h:80:2: error: expected specifier-qualifier-list before 'irqreturn_t' irqreturn_t (*handle_irq)(int irq_num, void *dev); ^~~~~~~~~~~ Include interrupt.h in proper place to avoid compilation error. Signed-off-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-08-13RISC-V: Add the directive for alignment of stvec's valueZong Li1-0/+2
The stvec's value must be 4 byte alignment by specification definition. These directives avoid to stvec be set the non-alignment value. Signed-off-by: Zong Li <zong@andestech.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-08-13clocksource: new RISC-V SBI timer driverPalmer Dabbelt3-9/+4
The RISC-V ISA defines a per-hart real-time clock and timer, which is present on all systems. The clock is accessed via the 'rdtime' pseudo-instruction (which reads a CSR), and the timer is set via an SBI call. Contains various improvements from Atish Patra <atish.patra@wdc.com>. Signed-off-by: Dmitriy Cherkasov <dmitriy@oss-tech.org> Signed-off-by: Palmer Dabbelt <palmer@dabbelt.com> [hch: remove dead code, add SPDX tags, used riscv_of_processor_hart(), minor cleanups, merged hotplug cpu support and other improvements from Atish] Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-08-13RISC-V: implement low-level interrupt handlingChristoph Hellwig2-11/+45
Add support for a routine that dispatches exceptions with the interrupt flags set to either the IPI or irqdomain code (and the clock source in the future). Loosely based on the irq-riscv-int.c irqchip driver from the RISC-V tree. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-08-13RISC-V: simplify software interrupt / IPI codeChristoph Hellwig1-4/+2
Rename handle_ipi to riscv_software_interrupt, drop the unused return value and move the prototype to irq.h together with riscv_timer_interupt. This allows simplifying the upcoming interrupt handling support. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-08-13RISC-V: remove timer leftoversChristoph Hellwig1-21/+0
This code is currently unused and will be added back later in a different place with the real interrupt and clocksource support. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-08-13RISC-V: Add early printk support via the SBI consolePalmer Dabbelt1-0/+27
This code lives entirely within the RISC-V arch code. I've left it within an "#ifdef CONFIG_EARLY_PRINTK" despite always having EARLY_PRINTK support on RISC-V just in case someone wants to remove it. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-08-13RISC-V: Don't increment sepc after breakpoint.Jim Wilson1-1/+0
Adding 4 to sepc is pointless, and is wrong if we executed a 2-byte compressed breakpoint. This plus a corresponding gdb patch allows compressed breakpoints to work in gdb. Gdb maintainers have already agreed that this is the right approach. Signed-off-by: Jim Wilson <jimw@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-08-13RISC-V: Use KBUILD_CFLAGS instead of KCFLAGS when building the vDSOPalmer Dabbelt1-2/+2
If you use a 64-bit compiler to build a 32-bit kernel then you'll get an error when building the vDSO due to a library mismatch. The happens because the relevant "-march" argument isn't supplied to the GCC run that generates one of the vDSO intermediate files. I'm not actually sure what the right thing to do here is as I'm not particularly familiar with the kernel build system. I poked the documentation and it appears that KCFLAGS is the correct thing to do (it's suggested that should be used when building modules), but we set KBUILD_CFLAGS in arch/riscv/Makefile. This does at least fix the build error. Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-07-04RISC-V: Fix the rv32i kernel buildPalmer Dabbelt1-11/+11
These patches for building 32-bit RISC-V kernel. - Fix the compile errors and warnings on RV32I. - Fix some incompatible problem on RV32I. - Add format.h for compatible of print format. The fixed width integer types format for Elf_Addr will move to generic header by another patch. For now, there are some warning about unexpected argument of type on RV32I. Change in v1: - Fix some error in v1 - Remove implementation of fixed width integer types format for Elf_Addr.
2018-07-04RISC-V: Fix PTRACE_SETREGSET bug.Jim Wilson1-1/+1
In riscv_gpr_set, pass regs instead of &regs to user_regset_copyin to fix gdb segfault. Signed-off-by: Jim Wilson <jimw@sifive.com> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-07-04RISC-V: Don't include irq-riscv-intc.hPalmer Dabbelt1-4/+0
This file has never existed in the upstream kernel, but it's guarded by an #ifdef that's also never existed in the upstream kernel. As a part of our interrupt controller refactoring this header is no longer necessary, but this reference managed to sneak in anyway. Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-07-04riscv: remove unnecessary of_platform_populate callRob Herring1-5/+0
The DT core will call of_platform_default_populate, so it is not necessary for arch specific code to call it unless there are custom match entries, auxdata or parent device. Neither of those apply here, so remove the call. Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: linux-riscv@lists.infradead.org Signed-off-by: Rob Herring <robh@kernel.org> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-07-04RISC-V: fix R_RISCV_ADD32/R_RISCV_SUB32 relocationsAndreas Schwab1-2/+2
The R_RISCV_ADD32/R_RISCV_SUB32 relocations should add/subtract the address of the symbol (without overflow check), not its contents. Signed-off-by: Andreas Schwab <schwab@suse.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>
2018-07-04RISC-V: Change variable type for 32-bit compatibleZong Li1-11/+11
Signed-off-by: Zong Li <zong@andestech.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Palmer Dabbelt <palmer@sifive.com>