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path: root/drivers/clocksource/arm_arch_timer.c
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2019-07-03Merge branch 'timers/vdso' into timers/coreThomas Gleixner
so the hyper-v clocksource update can be applied.
2019-06-25clocksource/drivers/arm_arch_timer: Extract elf_hwcap use to arch-helperAndrew Murray
Different mechanisms are used to test and set elf_hwcaps between ARM and ARM64, this results in the use of ifdeferry in this file when setting/testing for the EVTSTRM hwcap. Let's improve readability by extracting this to an arch helper. Signed-off-by: Andrew Murray <andrew.murray@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2019-06-19treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500Thomas Gleixner
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>
2019-06-12clocksource/drivers/arm_arch_timer: Don't trace count reader functionsJulien Thierry
With v5.2-rc1, The ftrace functions_graph tracer locks up whenever it is enabled on arm64. Since commit 0ea415390cd3 ("clocksource/arm_arch_timer: Use arch_timer_read_counter to access stable counters") a function pointer is consistently used to read the counter instead of potentially referencing an inlinable function. The graph tracers relies on accessing the timer counters to compute the time spent in functions which causes the lockup when attempting to trace these code paths. Annotate the arm arch timer counter accessors as notrace. Fixes: 0ea415390cd3 ("clocksource/arm_arch_timer: Use arch_timer_read_counter to access stable counters") Signed-off-by: Julien Thierry <julien.thierry@arm.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Steven Rostedt <rostedt@goodmis.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2019-05-06Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: "Mostly just incremental improvements here: - Introduce AT_HWCAP2 for advertising CPU features to userspace - Expose SVE2 availability to userspace - Support for "data cache clean to point of deep persistence" (DC PODP) - Honour "mitigations=off" on the cmdline and advertise status via sysfs - CPU timer erratum workaround (Neoverse-N1 #1188873) - Introduce perf PMU driver for the SMMUv3 performance counters - Add config option to disable the kuser helpers page for AArch32 tasks - Futex modifications to ensure liveness under contention - Rework debug exception handling to seperate kernel and user handlers - Non-critical fixes and cleanup" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (92 commits) Documentation: Add ARM64 to kernel-parameters.rst arm64/speculation: Support 'mitigations=' cmdline option arm64: ssbs: Don't treat CPUs with SSBS as unaffected by SSB arm64: enable generic CPU vulnerabilites support arm64: add sysfs vulnerability show for speculative store bypass arm64: Fix size of __early_cpu_boot_status clocksource/arm_arch_timer: Use arch_timer_read_counter to access stable counters clocksource/arm_arch_timer: Remove use of workaround static key clocksource/arm_arch_timer: Drop use of static key in arch_timer_reg_read_stable clocksource/arm_arch_timer: Direcly assign set_next_event workaround arm64: Use arch_timer_read_counter instead of arch_counter_get_cntvct watchdog/sbsa: Use arch_timer_read_counter instead of arch_counter_get_cntvct ARM: vdso: Remove dependency with the arch_timer driver internals arm64: Apply ARM64_ERRATUM_1188873 to Neoverse-N1 arm64: Add part number for Neoverse N1 arm64: Make ARM64_ERRATUM_1188873 depend on COMPAT arm64: Restrict ARM64_ERRATUM_1188873 mitigation to AArch32 arm64: mm: Remove pte_unmap_nested() arm64: Fix compiler warning from pte_unmap() with -Wunused-but-set-variable arm64: compat: Reduce address limit for 64K pages ...
2019-05-01Merge branch 'for-next/timers' of ↵Will Deacon
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux into for-next/core Conflicts: arch/arm64/Kconfig arch/arm64/include/asm/arch_timer.h
2019-04-30clocksource/arm_arch_timer: Use arch_timer_read_counter to access stable ↵Marc Zyngier
counters Instead of always going via arch_counter_get_cntvct_stable to access the counter workaround, let's have arch_timer_read_counter point to the right method. For that, we need to track whether any CPU in the system has a workaround for the counter. This is done by having an atomic variable tracking this. Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-30clocksource/arm_arch_timer: Remove use of workaround static keyMarc Zyngier
The use of a static key in a hotplug path has proved to be a real nightmare, and makes it impossible to have scream-free lockdep kernel. Let's remove the static key altogether, and focus on something saner. Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-30clocksource/arm_arch_timer: Direcly assign set_next_event workaroundMarc Zyngier
When a given timer is affected by an erratum and requires an alternative implementation of set_next_event, we do a rather complicated dance to detect and call the workaround on each set_next_event call. This is clearly idiotic, as we can perfectly detect whether this CPU requires a workaround while setting up the clock event device. This only requires the CPU-specific detection to be done a bit earlier, and we can then safely override the set_next_event pointer if we have a workaround associated to that CPU. Acked-by: Mark Rutland <mark.rutland@arm.com> Acked-by; Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-30arm64: Restrict ARM64_ERRATUM_1188873 mitigation to AArch32Marc Zyngier
We currently deal with ARM64_ERRATUM_1188873 by always trapping EL0 accesses for both instruction sets. Although nothing wrong comes out of that, people trying to squeeze the last drop of performance from buggy HW find this over the top. Oh well. Let's change the mitigation by flipping the counter enable bit on return to userspace. Non-broken HW gets an extra branch on the fast path, which is hopefully not the end of the world. The arch timer workaround is also removed. Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-16arm64: HWCAP: add support for AT_HWCAP2Andrew Murray
As we will exhaust the first 32 bits of AT_HWCAP let's start exposing AT_HWCAP2 to userspace to give us up to 64 caps. Whilst it's possible to use the remaining 32 bits of AT_HWCAP, we prefer to expand into AT_HWCAP2 in order to provide a consistent view to userspace between ILP32 and LP64. However internal to the kernel we prefer to continue to use the full space of elf_hwcap. To reduce complexity and allow for future expansion, we now represent hwcaps in the kernel as ordinals and use a KERNEL_HWCAP_ prefix. This allows us to support automatic feature based module loading for all our hwcaps. We introduce cpu_set_feature to set hwcaps which complements the existing cpu_have_feature helper. These helpers allow us to clean up existing direct uses of elf_hwcap and reduce any future effort required to move beyond 64 caps. For convenience we also introduce cpu_{have,set}_named_feature which makes use of the cpu_feature macro to allow providing a hwcap name without a {KERNEL_}HWCAP_ prefix. Signed-off-by: Andrew Murray <andrew.murray@arm.com> [will: use const_ilog2() and tweak documentation] Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-04-11clocksource/drivers/arm_arch_timer: Remove unneeded pr_fmt macroYangtao Li
After this commit ded24019b6b6f(clocksource: arm_arch_timer: clean up printk usage), the previous macro is redundant, so delete it. And move the new macro to the previous position. Signed-off-by: Yangtao Li <tiny.windzz@gmail.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2019-03-15Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM updates from Paolo Bonzini: "ARM: - some cleanups - direct physical timer assignment - cache sanitization for 32-bit guests s390: - interrupt cleanup - introduction of the Guest Information Block - preparation for processor subfunctions in cpu models PPC: - bug fixes and improvements, especially related to machine checks and protection keys x86: - many, many cleanups, including removing a bunch of MMU code for unnecessary optimizations - AVIC fixes Generic: - memcg accounting" * tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (147 commits) kvm: vmx: fix formatting of a comment KVM: doc: Document the life cycle of a VM and its resources MAINTAINERS: Add KVM selftests to existing KVM entry Revert "KVM/MMU: Flush tlb directly in the kvm_zap_gfn_range()" KVM: PPC: Book3S: Add count cache flush parameters to kvmppc_get_cpu_char() KVM: PPC: Fix compilation when KVM is not enabled KVM: Minor cleanups for kvm_main.c KVM: s390: add debug logging for cpu model subfunctions KVM: s390: implement subfunction processor calls arm64: KVM: Fix architecturally invalid reset value for FPEXC32_EL2 KVM: arm/arm64: Remove unused timer variable KVM: PPC: Book3S: Improve KVM reference counting KVM: PPC: Book3S HV: Fix build failure without IOMMU support Revert "KVM: Eliminate extra function calls in kvm_get_dirty_log_protect()" x86: kvmguest: use TSC clocksource if invariant TSC is exposed KVM: Never start grow vCPU halt_poll_ns from value below halt_poll_ns_grow_start KVM: Expose the initial start value in grow_halt_poll_ns() as a module parameter KVM: grow_halt_poll_ns() should never shrink vCPU halt_poll_ns KVM: x86/mmu: Consolidate kvm_mmu_zap_all() and kvm_mmu_zap_mmio_sptes() KVM: x86/mmu: WARN if zapping a MMIO spte results in zapping children ...
2019-02-23clocksource/drivers/arch_timer: Workaround for Allwinner A64 timer instabilitySamuel Holland
The Allwinner A64 SoC is known[1] to have an unstable architectural timer, which manifests itself most obviously in the time jumping forward a multiple of 95 years[2][3]. This coincides with 2^56 cycles at a timer frequency of 24 MHz, implying that the time went slightly backward (and this was interpreted by the kernel as it jumping forward and wrapping around past the epoch). Investigation revealed instability in the low bits of CNTVCT at the point a high bit rolls over. This leads to power-of-two cycle forward and backward jumps. (Testing shows that forward jumps are about twice as likely as backward jumps.) Since the counter value returns to normal after an indeterminate read, each "jump" really consists of both a forward and backward jump from the software perspective. Unless the kernel is trapping CNTVCT reads, a userspace program is able to read the register in a loop faster than it changes. A test program running on all 4 CPU cores that reported jumps larger than 100 ms was run for 13.6 hours and reported the following: Count | Event -------+--------------------------- 9940 | jumped backward 699ms 268 | jumped backward 1398ms 1 | jumped backward 2097ms 16020 | jumped forward 175ms 6443 | jumped forward 699ms 2976 | jumped forward 1398ms 9 | jumped forward 356516ms 9 | jumped forward 357215ms 4 | jumped forward 714430ms 1 | jumped forward 3578440ms This works out to a jump larger than 100 ms about every 5.5 seconds on each CPU core. The largest jump (almost an hour!) was the following sequence of reads: 0x0000007fffffffff → 0x00000093feffffff → 0x0000008000000000 Note that the middle bits don't necessarily all read as all zeroes or all ones during the anomalous behavior; however the low 10 bits checked by the function in this patch have never been observed with any other value. Also note that smaller jumps are much more common, with backward jumps of 2048 (2^11) cycles observed over 400 times per second on each core. (Of course, this is partially explained by lower bits rolling over more frequently.) Any one of these could have caused the 95 year time skip. Similar anomalies were observed while reading CNTPCT (after patching the kernel to allow reads from userspace). However, the CNTPCT jumps are much less frequent, and only small jumps were observed. The same program as before (except now reading CNTPCT) observed after 72 hours: Count | Event -------+--------------------------- 17 | jumped backward 699ms 52 | jumped forward 175ms 2831 | jumped forward 699ms 5 | jumped forward 1398ms Further investigation showed that the instability in CNTPCT/CNTVCT also affected the respective timer's TVAL register. The following values were observed immediately after writing CNVT_TVAL to 0x10000000: CNTVCT | CNTV_TVAL | CNTV_CVAL | CNTV_TVAL Error --------------------+------------+--------------------+----------------- 0x000000d4a2d8bfff | 0x10003fff | 0x000000d4b2d8bfff | +0x00004000 0x000000d4a2d94000 | 0x0fffffff | 0x000000d4b2d97fff | -0x00004000 0x000000d4a2d97fff | 0x10003fff | 0x000000d4b2d97fff | +0x00004000 0x000000d4a2d9c000 | 0x0fffffff | 0x000000d4b2d9ffff | -0x00004000 The pattern of errors in CNTV_TVAL seemed to depend on exactly which value was written to it. For example, after writing 0x10101010: CNTVCT | CNTV_TVAL | CNTV_CVAL | CNTV_TVAL Error --------------------+------------+--------------------+----------------- 0x000001ac3effffff | 0x1110100f | 0x000001ac4f10100f | +0x1000000 0x000001ac40000000 | 0x1010100f | 0x000001ac5110100f | -0x1000000 0x000001ac58ffffff | 0x1110100f | 0x000001ac6910100f | +0x1000000 0x000001ac66000000 | 0x1010100f | 0x000001ac7710100f | -0x1000000 0x000001ac6affffff | 0x1110100f | 0x000001ac7b10100f | +0x1000000 0x000001ac6e000000 | 0x1010100f | 0x000001ac7f10100f | -0x1000000 I was also twice able to reproduce the issue covered by Allwinner's workaround[4], that writing to TVAL sometimes fails, and both CVAL and TVAL are left with entirely bogus values. One was the following values: CNTVCT | CNTV_TVAL | CNTV_CVAL --------------------+------------+-------------------------------------- 0x000000d4a2d6014c | 0x8fbd5721 | 0x000000d132935fff (615s in the past) Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> ======================================================================== Because the CPU can read the CNTPCT/CNTVCT registers faster than they change, performing two reads of the register and comparing the high bits (like other workarounds) is not a workable solution. And because the timer can jump both forward and backward, no pair of reads can distinguish a good value from a bad one. The only way to guarantee a good value from consecutive reads would be to read _three_ times, and take the middle value only if the three values are 1) each unique and 2) increasing. This takes at minimum 3 counter cycles (125 ns), or more if an anomaly is detected. However, since there is a distinct pattern to the bad values, we can optimize the common case (1022/1024 of the time) to a single read by simply ignoring values that match the error pattern. This still takes no more than 3 cycles in the worst case, and requires much less code. As an additional safety check, we still limit the loop iteration to the number of max-frequency (1.2 GHz) CPU cycles in three 24 MHz counter periods. For the TVAL registers, the simple solution is to not use them. Instead, read or write the CVAL and calculate the TVAL value in software. Although the manufacturer is aware of at least part of the erratum[4], there is no official name for it. For now, use the kernel-internal name "UNKNOWN1". [1]: https://github.com/armbian/build/commit/a08cd6fe7ae9 [2]: https://forum.armbian.com/topic/3458-a64-datetime-clock-issue/ [3]: https://irclog.whitequark.org/linux-sunxi/2018-01-26 [4]: https://github.com/Allwinner-Homlet/H6-BSP4.9-linux/blob/master/drivers/clocksource/arm_arch_timer.c#L272 Acked-by: Maxime Ripard <maxime.ripard@bootlin.com> Tested-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Samuel Holland <samuel@sholland.org> Cc: stable@vger.kernel.org Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2019-02-19clocksource/arm_arch_timer: Store physical timer IRQ number for KVM on VHEAndre Przywara
A host running in VHE mode gets the EL2 physical timer as its time source (accessed using the EL1 sysreg accessors, which get re-directed to the EL2 sysregs by VHE). The EL1 physical timer remains unused by the host kernel, allowing us to pass that on directly to a KVM guest and saves us from emulating this timer for the guest on VHE systems. Store the EL1 Physical Timer's IRQ number in struct arch_timer_kvm_info on VHE systems to allow KVM to use it. Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@arm.com>
2018-10-01arm64: arch_timer: Add workaround for ARM erratum 1188873Marc Zyngier
When running on Cortex-A76, a timer access from an AArch32 EL0 task may end up with a corrupted value or register. The workaround for this is to trap these accesses at EL1/EL2 and execute them there. This only affects versions r0p0, r1p0 and r2p0 of the CPU. Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-07-10clocksource: arm_arch_timer: Set arch_mem_timer cpumask to cpu_possible_maskSudeep Holla
Currently, arch_mem_timer cpumask is set to cpu_all_mask which should be fine. However, cpu_possible_mask is more accurate and if there are other clockevent source in the system which are set to cpu_possible_mask, then having cpu_all_mask may result in issue. E.g. on a platform with arm,sp804 timer with rating 300 and cpu_possible_mask and this arch_mem_timer timer with rating 400 and cpu_all_mask, tick_check_preferred may choose both preferred as the cpumasks are not equal though they must be. This issue was root caused incorrectly initially and a fix was merged as commit 1332a9055801 ("tick: Prefer a lower rating device only if it's CPU local device"). Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Kevin Hilman <khilman@baylibre.com> Tested-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> Cc: linux-arm-kernel@lists.infradead.org Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Link: https://lkml.kernel.org/r/1531151136-18297-2-git-send-email-sudeep.holla@arm.com
2017-11-16Merge tag 'kvm-4.15-1' of git://git.kernel.org/pub/scm/virt/kvm/kvmLinus Torvalds
Pull KVM updates from Radim Krčmář: "First batch of KVM changes for 4.15 Common: - Python 3 support in kvm_stat - Accounting of slabs to kmemcg ARM: - Optimized arch timer handling for KVM/ARM - Improvements to the VGIC ITS code and introduction of an ITS reset ioctl - Unification of the 32-bit fault injection logic - More exact external abort matching logic PPC: - Support for running hashed page table (HPT) MMU mode on a host that is using the radix MMU mode; single threaded mode on POWER 9 is added as a pre-requisite - Resolution of merge conflicts with the last second 4.14 HPT fixes - Fixes and cleanups s390: - Some initial preparation patches for exitless interrupts and crypto - New capability for AIS migration - Fixes x86: - Improved emulation of LAPIC timer mode changes, MCi_STATUS MSRs, and after-reset state - Refined dependencies for VMX features - Fixes for nested SMI injection - A lot of cleanups" * tag 'kvm-4.15-1' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (89 commits) KVM: s390: provide a capability for AIS state migration KVM: s390: clear_io_irq() requests are not expected for adapter interrupts KVM: s390: abstract conversion between isc and enum irq_types KVM: s390: vsie: use common code functions for pinning KVM: s390: SIE considerations for AP Queue virtualization KVM: s390: document memory ordering for kvm_s390_vcpu_wakeup KVM: PPC: Book3S HV: Cosmetic post-merge cleanups KVM: arm/arm64: fix the incompatible matching for external abort KVM: arm/arm64: Unify 32bit fault injection KVM: arm/arm64: vgic-its: Implement KVM_DEV_ARM_ITS_CTRL_RESET KVM: arm/arm64: Document KVM_DEV_ARM_ITS_CTRL_RESET KVM: arm/arm64: vgic-its: Free caches when GITS_BASER Valid bit is cleared KVM: arm/arm64: vgic-its: New helper functions to free the caches KVM: arm/arm64: vgic-its: Remove kvm_its_unmap_device arm/arm64: KVM: Load the timer state when enabling the timer KVM: arm/arm64: Rework kvm_timer_should_fire KVM: arm/arm64: Get rid of kvm_timer_flush_hwstate KVM: arm/arm64: Avoid phys timer emulation in vcpu entry/exit KVM: arm/arm64: Move phys_timer_emulate function KVM: arm/arm64: Use kvm_arm_timer_set/get_reg for guest register traps ...
2017-11-15Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: "The big highlight is support for the Scalable Vector Extension (SVE) which required extensive ABI work to ensure we don't break existing applications by blowing away their signal stack with the rather large new vector context (<= 2 kbit per vector register). There's further work to be done optimising things like exception return, but the ABI is solid now. Much of the line count comes from some new PMU drivers we have, but they're pretty self-contained and I suspect we'll have more of them in future. Plenty of acronym soup here: - initial support for the Scalable Vector Extension (SVE) - improved handling for SError interrupts (required to handle RAS events) - enable GCC support for 128-bit integer types - remove kernel text addresses from backtraces and register dumps - use of WFE to implement long delay()s - ACPI IORT updates from Lorenzo Pieralisi - perf PMU driver for the Statistical Profiling Extension (SPE) - perf PMU driver for Hisilicon's system PMUs - misc cleanups and non-critical fixes" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (97 commits) arm64: Make ARMV8_DEPRECATED depend on SYSCTL arm64: Implement __lshrti3 library function arm64: support __int128 on gcc 5+ arm64/sve: Add documentation arm64/sve: Detect SVE and activate runtime support arm64/sve: KVM: Hide SVE from CPU features exposed to guests arm64/sve: KVM: Treat guest SVE use as undefined instruction execution arm64/sve: KVM: Prevent guests from using SVE arm64/sve: Add sysctl to set the default vector length for new processes arm64/sve: Add prctl controls for userspace vector length management arm64/sve: ptrace and ELF coredump support arm64/sve: Preserve SVE registers around EFI runtime service calls arm64/sve: Preserve SVE registers around kernel-mode NEON use arm64/sve: Probe SVE capabilities and usable vector lengths arm64: cpufeature: Move sys_caps_initialised declarations arm64/sve: Backend logic for setting the vector length arm64/sve: Signal handling support arm64/sve: Support vector length resetting for new processes arm64/sve: Core task context handling arm64/sve: Low-level CPU setup ...
2017-11-06arm64: Use physical counter for in-kernel reads when booted in EL2Christoffer Dall
Using the physical counter allows KVM to retain the offset between the virtual and physical counter as long as it is actively running a VCPU. As soon as a VCPU is released, another thread is scheduled or we start running userspace applications, we reset the offset to 0, so that userspace accessing the virtual timer can still read the virtual counter and get the same view of time as the kernel. This opens up potential improvements for KVM performance, but we have to make a few adjustments to preserve system consistency. Currently get_cycles() is hardwired to arch_counter_get_cntvct() on arm64, but as we move to using the physical timer for the in-kernel time-keeping on systems that boot in EL2, we should use the same counter for get_cycles() as for other in-kernel timekeeping operations. Similarly, implementations of arch_timer_set_next_event_phys() is modified to use the counter specific to the timer being programmed. VHE kernels or kernels continuing to use the virtual timer are unaffected. Cc: Will Deacon <will.deacon@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-11-06arm64: Implement arch_counter_get_cntpct to read the physical counterChristoffer Dall
As we are about to use the physical counter on arm64 systems that have KVM support, implement arch_counter_get_cntpct() and the associated errata workaround functionality for stable timer reads. Cc: Will Deacon <will.deacon@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-10-19clocksource/drivers/arm_arch_timer: Fix DEFINE_PER_CPU expansionMark Rutland
Our ctags mangling script can't handle newlines inside of a DEFINE_PER_CPU(), leading to an annoying message whenever tags are built: ctags: Warning: drivers/clocksource/arm_arch_timer.c:302: null expansion of name pattern "\1" This was dealt with elsewhere in commit: 25528213fe9f75f4 ("tags: Fix DEFINE_PER_CPU expansions") ... by ensuring each DEFINE_PER_CPU() was contained on a single line, even where this would violate the usual code style (checkpatch warnings and all). Let's do the same for the arch timer driver, and get rid of the distraction. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2017-10-19clocksource/drivers/arm_arch_timer: Validate CNTFRQ after enabling frameArd Biesheuvel
The ACPI GTDT code validates the CNTFRQ field of each MMIO timer frame against the CNTFRQ system register of the current CPU, to ensure that they are equal, which is mandated by the architecture. However, reading the CNTFRQ field of a frame is not possible until the RFRQ bit in the frame's CNTACRn register is set, and doing so before that willl produce the following error: arch_timer: [Firmware Bug]: CNTFRQ mismatch: frame @ 0x00000000e0be0000: (0x00000000), CPU: (0x0ee6b280) arch_timer: Disabling MMIO timers due to CNTFRQ mismatch arch_timer: Failed to initialize memory-mapped timer. The reason is that the CNTFRQ field is RES0 if access is not enabled. So move the validation of CNTFRQ into the loop that iterates over the timers to find the best frame, but defer it until after we have selected the best frame, which should also have enabled the RFRQ bit. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2017-10-13arm_arch_timer: Expose event stream statusJulien Thierry
The arch timer configuration for a CPU might get reset after suspending said CPU. In order to reliably use the event stream in the kernel (e.g. for delays), we keep track of the state where we can safely consider the event stream as properly configured. After writing to cntkctl, we issue an ISB to ensure that subsequent delay loops can rely on the event stream being enabled. Signed-off-by: Julien Thierry <julien.thierry@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-08-25Merge branch 'linus' into locking/core, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-08-10clocksource/drivers/arm_arch_timer: Fix mem frame loop initializationMatthias Kaehlcke
The loop to find the best memory frame in arch_timer_mem_acpi_init() initializes the loop counter with itself ('i = i'), which is suspicious in the first place and pointed out by clang. The loop condition is 'i < timer_count' and a prior for loop exits when 'i' reaches 'timer_count', therefore the second loop is never executed. Initialize the loop counter with 0 to iterate over all timers, which supposedly was the intention before the typo monster attacked. Fixes: c2743a36765d3 ("clocksource: arm_arch_timer: add GTDT support for memory-mapped timer") Signed-off-by: Matthias Kaehlcke <mka@chromium.org> Reported-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2017-08-10clocksource/arm_arch_timer: Use static_branch_enable_cpuslocked()Marc Zyngier
Use the new static_branch_enable_cpuslocked() function to switch the workaround static key on the CPU hotplug path. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Leo Yan <leo.yan@linaro.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/20170801080257.5056-5-marc.zyngier@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-06-21Merge branch 'timers/urgent' into timers/coreThomas Gleixner
Pick up dependent changes.
2017-06-14clocksource/drivers: Rename CLOCKSOURCE_ACPI_DECLARE to TIMER_ACPI_DECLAREDaniel Lezcano
The macro name is now renamed to 'TIMER_ACPI_DECLARE' for consistency with the CLOCKSOURCE_OF_DECLARE => TIMER_OF_DECLARE change. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2017-06-14clocksource/drivers: Rename CLOCKSOURCE_OF_DECLARE to TIMER_OF_DECLAREDaniel Lezcano
The CLOCKSOURCE_OF_DECLARE macro is used widely for the timers to declare the clocksource at early stage. However, this macro is also used to initialize the clockevent if any, or the clockevent only. It was originally suggested to declare another macro to initialize a clockevent, so in order to separate the two entities even they belong to the same IP. This was not accepted because of the impact on the DT where splitting a clocksource/clockevent definition does not make sense as it is a Linux concept not a hardware description. On the other side, the clocksource has not interrupt declared while the clockevent has, so it is easy from the driver to know if the description is for a clockevent or a clocksource, IOW it could be implemented at the driver level. So instead of dealing with a named clocksource macro, let's use a more generic one: TIMER_OF_DECLARE. The patch has not functional changes. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org> Acked-by: Heiko Stuebner <heiko@sntech.de> Acked-by: Neil Armstrong <narmstrong@baylibre.com> Acked-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Matthias Brugger <matthias.bgg@gmail.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
2017-06-12clocksource/drivers/arm_arch_timer: Fix read and iounmap of incorrect variableFrank Rowand
Fix boot warning 'Trying to vfree() nonexistent vm area' from arch_timer_mem_of_init(). Refactored code attempts to read and iounmap using address frame instead of address ioremap(frame->cntbase). Fixes: c389d701dfb70 ("clocksource: arm_arch_timer: split MMIO timer probing.") Signed-off-by: Frank Rowand <frank.rowand@sony.com> Reviewed-by: Fu Wei <fu.wei@linaro.org> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
2017-05-09clocksource/arm_arch_timer: Fix arch_timer_mem_find_best_frame()Sudeep Holla
arch_timer_mem_find_best_frame() looks through ARCH_TIMER_MEM_MAX_FRAMES frames even after finding matches to ensure the best frame is chosen, which means the variable frame will point to the last valid frame but not necessarily the best frame. On Juno, we get the following error as the wrong frame is returned as the best frame from arch_timer_mem_find_best_frame(): arch_timer: Unable to map frame @ 0x0000000000000000 arch_timer: Frame missing phys irq. Failed to initialize '/timer@2a810000': -22 Fix the issue by correctly returning the best frame from arch_timer_mem_find_best_frame(). Fixes: c389d701dfb7 ("clocksource: arm_arch_timer: split MMIO timer probing.") Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/1494246747-17267-1-git-send-email-sudeep.holla@arm.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-20arm64/arch_timer: Mark errata handlers as __maybe_unusedArnd Bergmann
In some rare randconfig builds, we end up with two functions being entirely unused: drivers/clocksource/arm_arch_timer.c:342:12: error: 'erratum_set_next_event_tval_phys' defined but not used [-Werror=unused-function] static int erratum_set_next_event_tval_phys(unsigned long evt, drivers/clocksource/arm_arch_timer.c:335:12: error: 'erratum_set_next_event_tval_virt' defined but not used [-Werror=unused-function] static int erratum_set_next_event_tval_virt(unsigned long evt, We could add an #ifdef around them, but we would already have to check for several symbols there and there is a chance this would get more complicated over time, so marking them as __maybe_unused is the simplest way to avoid the harmless warnings. Fixes: 01d3e3ff2608 ("arm64: arch_timer: Rework the set_next_event workarounds") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: Christoffer Dall <christoffer.dall@linaro.org> Link: http://lkml.kernel.org/r/20170419173737.3846098-1-arnd@arndb.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2017-04-19clocksource: arm_arch_timer: add GTDT support for memory-mapped timerFu Wei
The patch add memory-mapped timer register support by using the information provided by the new GTDT driver of ACPI. Signed-off-by: Fu Wei <fu.wei@linaro.org> Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> [Mark: verify CNTFRQ, only register the first frame] Signed-off-by: Mark Rutland <mark.rutland@arm.com>
2017-04-19clocksource: arm_arch_timer: simplify ACPI support code.Fu Wei
The patch update arm_arch_timer driver to use the function provided by the new GTDT driver of ACPI. By this way, arm_arch_timer.c can be simplified, and separate all the ACPI GTDT knowledge from this timer driver. Signed-off-by: Fu Wei <fu.wei@linaro.org> Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org> Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com> Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Signed-off-by: Mark Rutland <mark.rutland@arm.com>
2017-04-19clocksource: arm_arch_timer: split MMIO timer probing.Fu Wei
Currently the code to probe MMIO architected timers mixes DT parsing with actual poking of hardware. This makes the code harder than necessary to understand, and makes it difficult to add support for probing via ACPI. This patch splits the DT parsing from HW probing. The DT parsing now lives in arch_timer_mem_of_init(), which fills in an arch_timer_mem structure that it hands to probing functions that can be reused for ACPI support. Since the rate detection logic will be slight different when using ACPI, the probing is performed as a number of steps. This results in more code for the moment, and some arguably redundant work, but simplifies matters considerably when ACPI support is added. Signed-off-by: Fu Wei <fu.wei@linaro.org> [Mark: refactor the probing split] Signed-off-by: Mark Rutland <mark.rutland@arm.com>
2017-04-19clocksource: arm_arch_timer: move arch_timer_needs_of_probing into DT init callFu Wei
To cleanly split code paths specific to ACPI or DT at a higher level, this patch removes arch_timer_init(), folding the relevant parts of its logic into existing callers. This pathes the way for further rework, and saves a few lines. Signed-off-by: Fu Wei <fu.wei@linaro.org> Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> [Mark: reword commit message] Signed-off-by: Mark Rutland <mark.rutland@arm.com>
2017-04-19clocksource: arm_arch_timer: refactor arch_timer_needs_probingFu Wei
When booting with DT, it's possible for timer nodes to be probed in any order. Some common initialisation needs to occur after all nodes have been probed, and arch_timer_common_init() has code to detect when this has happened. This logic is DT-specific, and it would be best to factor it out of the common code that will be shared with ACPI. This patch folds this into the existing arch_timer_needs_probing(), which is renamed to arch_timer_needs_of_probing(), and no longer takes any arguments. This is only called when using DT, and not when using ACPI, which will have a deterministic probe order. Signed-off-by: Fu Wei <fu.wei@linaro.org> Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> [Mark: reword commit message] Signed-off-by: Mark Rutland <mark.rutland@arm.com>
2017-04-19clocksource: arm_arch_timer: split dt-only rate handlingFu Wei
For historical reasons, rate detection when probing via DT is somewhat convoluted. We tried to package this up in arch_timer_detect_rate(), but with the addition of ACPI worse, and gets in the way of stringent rate checking when ACPI is used. This patch makes arch_timer_detect_rate() specific to DT, ripping out ACPI logic. In preparation for rework of the MMIO timer probing, the reading of the relevant CNTFRQ register is factored out to callers. The function is then renamed to arch_timer_of_configure_rate(), which better represents its new place in the world. Comments are added in the DT and ACPI probe paths to explain this. Signed-off-by: Fu Wei <fu.wei@linaro.org> [Mark: reword commit message] Signed-off-by: Mark Rutland <mark.rutland@arm.com>
2017-04-10clocksource: arm_arch_timer: rework PPI selectionFu Wei
Currently, the arch timer driver uses ARCH_TIMER_PHYS_SECURE_PPI to mean the driver will use the secure PPI *and* potentially also use the non-secure PPI. This is somewhat confusing. For arm64 it never makes sense to use the secure PPI, but we do anyway, inheriting this behaviour from 32-bit arm. For ACPI, we may not even have a valid secure PPI, so we need to be able to only request the non-secure PPI. To that end, this patch reworks the timer driver so that we can request the non-secure PPI alone. The PPI selection is split out into a new function, arch_timer_select_ppi(), and verification of the selected PPI is shifted out to callers (as DT may select the PPI by other means and must handle this anyway). We now consistently use arch_timer_has_nonsecure_ppi() to determine whether we must manage a non-secure PPI *in addition* to a secure PPI. When we only have a non-secure PPI, this returns false. Signed-off-by: Fu Wei <fu.wei@linaro.org> Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com> [Mark: reword commit message] Signed-off-by: Mark Rutland <mark.rutland@arm.com>
2017-04-10clocksource: arm_arch_timer: add a new enum for spi typeFu Wei
This patch add a new enum "arch_timer_spi_nr" and use it in the driver. Just for code's readability, no functional change. Signed-off-by: Fu Wei <fu.wei@linaro.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Mark Rutland <mark.rutland@arm.com>
2017-04-10clocksource: arm_arch_timer: move enums and defines to header fileFu Wei
To support the arm_arch_timer via ACPI we need to share defines and enums between the driver and the ACPI parser code. So we split out the relevant defines and enums into arm_arch_timer.h. No functional change. Signed-off-by: Fu Wei <fu.wei@linaro.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com> Signed-off-by: Mark Rutland <mark.rutland@arm.com>
2017-04-10clocksource: arm_arch_timer: rename the PPI enumFu Wei
In preparation for moving the PPI enum out into a header, rename the enum and its constituent values these so they are namespaced w.r.t. the arch timer. This will aid consistency and avoid potential name clashes when this move occurs. No functional change. Signed-off-by: Fu Wei <fu.wei@linaro.org> Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com> [Mark: reword commit message] Signed-off-by: Mark Rutland <mark.rutland@arm.com>
2017-04-10clocksource: arm_arch_timer: rename type macrosFu Wei
In preparation for moving the type macros out into a header, rename these so they are namespaced w.r.t. the arch timer. We'll apply the same prefix to other definitions in subsequent patches. This will aid consistency and avoid potential name clahses when this move occurs. No functional change. Signed-off-by: Fu Wei <fu.wei@linaro.org> Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com> [Mark: reword commit message] Signed-off-by: Mark Rutland <mark.rutland@arm.com>
2017-04-10clocksource: arm_arch_timer: clean up printk usageFu Wei
Almost all string in the arm_arch_timer driver duplicate an common prefix (though a few do not). For consistency, it would be better to use pr_fmt(), and always use this prefix. At the same time, we may as well clean up some whitespace issues in arch_timer_banner and arch_timer_init. No functional change. Signed-off-by: Fu Wei <fu.wei@linaro.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Xiongfeng Wang <wangxiongfeng2@huawei.com> [Mark: reword commit message] Signed-off-by: Mark Rutland <mark.rutland@arm.com>
2017-04-07arm64: arch_timer: Add HISILICON_ERRATUM_161010101 ACPI matching dataMarc Zyngier
In order to deal with ACPI enabled platforms suffering from the HISILICON_ERRATUM_161010101, let's add the required OEM data that allow the workaround to be enabled. Acked-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: dann frazier <dann.frazier@canonical.com> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-04-07arm64: arch_timer: Allow erratum matching with ACPI OEM informationMarc Zyngier
Just as we're able to identify a broken platform using some DT information, let's enable a way to spot the offenders with ACPI. The difference is that we can only match on some OEM info instead of implementation-specific properties. So in order to avoid the insane multiplication of errata structures, we allow an array of OEM descriptions to be attached to an erratum structure. Acked-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: dann frazier <dann.frazier@canonical.com> Tested-by: Hanjun Guo <hanjun.guo@linaro.org> Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-04-07arm64: arch_timer: Workaround for Cortex-A73 erratum 858921Marc Zyngier
Cortex-A73 (all versions) counter read can return a wrong value when the counter crosses a 32bit boundary. The workaround involves performing the read twice, and to return one or the other depending on whether a transition has taken place. Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-04-07arm64: arch_timer: Enable CNTVCT_EL0 trap if workaround is enabledMarc Zyngier
Userspace being allowed to use read CNTVCT_EL0 anytime (and not only in the VDSO), we need to enable trapping whenever a cntvct workaround is enabled on a given CPU. Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-04-07arm64: arch_timer: Save cntkctl_el1 as a per-cpu variableMarc Zyngier
As we're about to allow per CPU cntkctl_el1 configuration, we cannot rely on the register value to be common when performing power management. Let's turn saved_cntkctl into a per-cpu variable. Acked-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>