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path: root/arch/arm64/kernel/cpuinfo.c
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2017-08-09arm64: Expose DC CVAP to userspaceRobin Murphy
The ARMv8.2-DCPoP feature introduces persistent memory support to the architecture, by defining a point of persistence in the memory hierarchy, and a corresponding cache maintenance operation, DC CVAP. Expose the support via HWCAP and MRS emulation. Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-06-30arm64: cpuinfo: constify attribute_group structures.Arvind Yadav
attribute_groups are not supposed to change at runtime. All functions working with attribute_groups provided by <linux/sysfs.h> work with const attribute_group. So mark the non-const structs as const. Signed-off-by: Arvind Yadav <arvind.yadav.cs@gmail.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-03-20arm64: v8.3: Support for weaker release consistencySuzuki K Poulose
ARMv8.3 adds new instructions to support Release Consistent processor consistent (RCpc) model, which is weaker than the RCsc model. Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-03-20arm64: v8.3: Support for complex number instructionsSuzuki K Poulose
ARM v8.3 adds support for new instructions to aid floating-point multiplication and addition of complex numbers. Expose the support via HWCAP and MRS emulation Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-03-20arm64: v8.3: Support for Javascript conversion instructionSuzuki K Poulose
ARMv8.3 adds support for a new instruction to perform conversion from double precision floating point to integer to match the architected behaviour of the equivalent Javascript conversion. Expose the availability via HWCAP and MRS emulation. Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-03-20arm64: cache: Identify VPIPT I-cachesWill Deacon
Add support for detecting VPIPT I-caches, as introduced by ARMv8.2. Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-03-20arm64: cache: Merge cachetype.h into cache.hWill Deacon
cachetype.h and cache.h are small and both obviously related to caches. Merge them together to reduce clutter. Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-03-20arm64: cache: Remove support for ASID-tagged VIVT I-cachesWill Deacon
As a recent change to ARMv8, ASID-tagged VIVT I-caches are removed retrospectively from the architecture. Consequently, we don't need to support them in Linux either. Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-03-20arm64: cpuinfo: remove I-cache VIPT aliasing detectionWill Deacon
The CCSIDR_EL1.{NumSets,Associativity,LineSize} fields are only for use in conjunction with set/way cache maintenance and are not guaranteed to represent the actual microarchitectural features of a design. The architecture explicitly states: | You cannot make any inference about the actual sizes of caches based | on these parameters. We currently use these fields to determine whether or the I-cache is aliasing, which is bogus and known to break on some platforms. Instead, assume the I-cache is always aliasing if it advertises a VIPT policy. Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-01-12arm64: Advertise support for Rounding double multiply instructionsSuzuki K Poulose
ARM v8.1 extensions include support for rounding double multiply add/subtract instructions to the A64 SIMD instructions set. Let the userspace know about it via a HWCAP bit. Cc: Mark Rutland <mark.rutland@arm.com> Cc: Will Deacon <will.deacon@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-01-12arm64: cpufeature: Expose CPUID registers by emulationSuzuki K Poulose
This patch adds the hook for emulating MRS instruction to export the 'user visible' value of supported system registers. We emulate only the following id space for system registers: Op0=3, Op1=0, CRn=0, CRm=[0, 4-7] The rest will fall back to SIGILL. This capability is also advertised via a new HWCAP_CPUID. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Will Deacon <will.deacon@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> [will: add missing static keyword to enable_mrs_emulation] Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-12-02arm64/cpuinfo: Convert to hotplug state machineAnna-Maria Gleixner
Install the callbacks via the state machine and let the core invoke the callbacks on the already online CPUs. Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: rt@linutronix.de Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/20161126231350.10321-17-bigeasy@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-12-02arm64/cpuinfo: Make hotplug notifier symmetricAnna-Maria Gleixner
There is no requirement to keep the sysfs files around until the CPU is completely dead. Remove them during the DOWN_PREPARE notification. This is a preparatory patch for converting to the hotplug state machine. Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de> Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: rt@linutronix.de Cc: linux-arm-kernel@lists.infradead.org Link: http://lkml.kernel.org/r/20161126231350.10321-16-bigeasy@linutronix.de Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-09-09arm64: Rearrange CPU errata workaround checksSuzuki K Poulose
Right now we run through the work around checks on a CPU from __cpuinfo_store_cpu. There are some problems with that: 1) We initialise the system wide CPU feature registers only after the Boot CPU updates its cpuinfo. Now, if a work around depends on the variance of a CPU ID feature (e.g, check for Cache Line size mismatch), we have no way of performing it cleanly for the boot CPU. 2) It is out of place, invoked from __cpuinfo_store_cpu() in cpuinfo.c. It is not an obvious place for that. This patch rearranges the CPU specific capability(aka work around) checks. 1) At the moment we use verify_local_cpu_capabilities() to check if a new CPU has all the system advertised features. Use this for the secondary CPUs to perform the work around check. For that we rename verify_local_cpu_capabilities() => check_local_cpu_capabilities() which: If the system wide capabilities haven't been initialised (i.e, the CPU is activated at the boot), update the system wide detected work arounds. Otherwise (i.e a CPU hotplugged in later) verify that this CPU conforms to the system wide capabilities. 2) Boot CPU updates the work arounds from smp_prepare_boot_cpu() after we have initialised the system wide CPU feature values. Cc: Mark Rutland <mark.rutland@arm.com> Cc: Andre Przywara <andre.przywara@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-09-09arm64: Use consistent naming for errata handlingSuzuki K Poulose
This is a cosmetic change to rename the functions dealing with the errata work arounds to be more consistent with their naming. 1) check_local_cpu_errata() => update_cpu_errata_workarounds() check_local_cpu_errata() actually updates the system's errata work arounds. So rename it to reflect the same. 2) verify_local_cpu_errata() => verify_local_cpu_errata_workarounds() Use errata_workarounds instead of _errata. Cc: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-07-12arm64: cpuinfo: Expose MIDR_EL1 and REVIDR_EL1 to sysfsSteve Capper
It can be useful for JIT software to be aware of MIDR_EL1 and REVIDR_EL1 to ascertain the presence of any core errata that could affect code generation. This patch exposes these registers through sysfs: /sys/devices/system/cpu/cpu$ID/regs/identification/midr_el1 /sys/devices/system/cpu/cpu$ID/regs/identification/revidr_el1 where $ID is the cpu number. For big.LITTLE systems, one can have a mixture of cores (e.g. Cortex A53 and Cortex A57), thus all CPUs need to be enumerated. If the kernel does not have valid information to populate these entries with, an empty string is returned to userspace. Cc: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Steve Capper <steve.capper@linaro.org> [suzuki.poulose@arm.com: ABI documentation updates, hotplug notifiers, kobject changes] Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-05-31arm64: Provide "model name" in /proc/cpuinfo for PER_LINUX32 tasksCatalin Marinas
This patch brings the PER_LINUX32 /proc/cpuinfo format more in line with the 32-bit ARM one by providing an additional line: model name : ARMv8 Processor rev X (v8l) Cc: <stable@vger.kernel.org> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-05-11arm64: cpuinfo: Missing NULL terminator in compat_hwcap_strJulien Grall
The loop that browses the array compat_hwcap_str will stop when a NULL is encountered, however NULL is missing at the end of array. This will lead to overrun until a NULL is found somewhere in the following memory. In reality, this works out because the compat_hwcap2_str array tends to follow immediately in memory, and that *is* terminated correctly. Furthermore, the unsigned int compat_elf_hwcap is checked before printing each capability, so we end up doing the right thing because the size of the two arrays is less than 32. Still, this is an obvious mistake and should be fixed. Note for backporting: commit 12d11817eaafa414 ("arm64: Move /proc/cpuinfo handling code") moved this code in v4.4. Prior to that commit, the same change should be made in arch/arm64/kernel/setup.c. Fixes: 44b82b7700d0 "arm64: Fix up /proc/cpuinfo" Cc: <stable@vger.kernel.org> # v3.19+ (but see note above prior to v4.4) Signed-off-by: Julien Grall <julien.grall@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-04-20arm64: cpufeature: Check availability of AArch32Suzuki K Poulose
On ARMv8 support for AArch32 state is optional. Hence it is not safe to check the AArch32 ID registers for sanity, which could lead to false warnings. This patch makes sure that the AArch32 state is implemented before we keep track of the 32bit ID registers. As per ARM ARM (D.1.21.2 - Support for Exception Levels and Execution States, DDI0487A.h), checking the support for AArch32 at EL0 is good enough to check the support for AArch32 (i.e, AArch32 at EL1 => AArch32 at EL0, but not vice versa). Tested-by: Yury Norov <ynorov@caviumnetworks.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-03-04arm64: make mrs_s prefixing implicit in read_cpuidMark Rutland
Commit 0f54b14e76f5302a ("arm64: cpufeature: Change read_cpuid() to use sysreg's mrs_s macro") changed read_cpuid to require a SYS_ prefix on register names, to allow manual assembly of registers unknown by the toolchain, using tables in sysreg.h. This interacts poorly with commit 42b55734030c1f72 ("efi/arm64: Check for h/w support before booting a >4 KB granular kernel"), which is curretly queued via the tip tree, and uses read_cpuid without a SYS_ prefix. Due to this, a build of next-20160304 fails if EFI and 64K pages are selected. To avoid this issue when trees are merged, move the required SYS_ prefixing into read_cpuid, and revert all of the updated callsites to pass plain register names. This effectively reverts the bulk of commit 0f54b14e76f5302a. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: James Morse <james.morse@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-26arm64: Add support for Half precision floating pointSuzuki K Poulose
ARMv8.2 extensions [1] include an optional feature, which supports half precision(16bit) floating point/asimd data processing instructions. This patch adds support for detecting and exposing the same to the userspace via HWCAPs [1] https://community.arm.com/groups/processors/blog/2016/01/05/armv8-a-architecture-evolution Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-18arm64: add ARMv8.2 id_aa64mmfr2 boiler plateJames Morse
ARMv8.2 adds a new feature register id_aa64mmfr2. This patch adds the cpu feature boiler plate used by the actual features in later patches. Signed-off-by: James Morse <james.morse@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-18arm64: cpufeature: Change read_cpuid() to use sysreg's mrs_s macroJames Morse
Older assemblers may not have support for newer feature registers. To get round this, sysreg.h provides a 'mrs_s' macro that takes a register encoding and generates the raw instruction. Change read_cpuid() to use mrs_s in all cases so that new registers don't have to be a special case. Including sysreg.h means we need to move the include and definition of read_cpuid() after the #ifndef __ASSEMBLY__ to avoid syntax errors in vmlinux.lds. Signed-off-by: James Morse <james.morse@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-11-19arm64: restore bogomips information in /proc/cpuinfoYang Shi
As previously reported, some userspace applications depend on bogomips showed by /proc/cpuinfo. Although there is much less legacy impact on aarch64 than arm, it does break libvirt. This patch reverts commit 326b16db9f69 ("arm64: delay: don't bother reporting bogomips in /proc/cpuinfo"), but with some tweak due to context change and without the pr_info(). Fixes: 326b16db9f69 ("arm64: delay: don't bother reporting bogomips in /proc/cpuinfo") Signed-off-by: Yang Shi <yang.shi@linaro.org> Acked-by: Will Deacon <will.deacon@arm.com> Cc: <stable@vger.kernel.org> # 3.12+ Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-21arm64: Constify hwcap name string arraysDave Martin
The hwcap string arrays used for generating the contents of /proc/cpuinfo are currently arrays of non-const pointers. There's no need for these pointers to be mutable, so this patch makes them const so that they can be moved to .rodata. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-21arm64: Delay cpu feature capability checksSuzuki K. Poulose
At the moment we run through the arm64_features capability list for each CPU and set the capability if one of the CPU supports it. This could be problematic in a heterogeneous system with differing capabilities. Delay the CPU feature checks until all the enabled CPUs are up(i.e, smp_cpus_done(), so that we can make better decisions based on the overall system capability. Once we decide and advertise the capabilities the alternatives can be applied. From this state, we cannot roll back a feature to disabled based on the values from a new hotplugged CPU, due to the runtime patching and other reasons. So, for all new CPUs, we need to make sure that they have the established system capabilities. Failing which, we bring the CPU down, preventing it from turning online. Once the capabilities are decided, any new CPU booting up goes through verification to ensure that it has all the enabled capabilities and also invokes the respective enable() method on the CPU. The CPU errata checks are not delayed and is still executed per-CPU to detect the respective capabilities. If we ever come across a non-errata capability that needs to be checked on each-CPU, we could introduce them via a new capability table(or introduce a flag), which can be processed per CPU. The next patch will make the feature checks use the system wide safe value of a feature register. NOTE: The enable() methods associated with the capability is scheduled on all the CPUs (which is the only use case at the moment). If we need a different type of 'enable()' which only needs to be run once on any CPU, we should be able to handle that when needed. Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Tested-by: Dave Martin <Dave.Martin@arm.com> [catalin.marinas@arm.com: static variable and coding style fixes] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-21arm64: Consolidate CPU Sanity check to CPU Feature infrastructureSuzuki K. Poulose
This patch consolidates the CPU Sanity check to the new infrastructure. Cc: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Tested-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-21arm64: Keep track of CPU feature registersSuzuki K. Poulose
This patch adds an infrastructure to keep track of the CPU feature registers on the system. For each register, the infrastructure keeps track of the system wide safe value of the feature bits. Also, tracks the which fields of a register should be matched strictly across all the CPUs on the system for the SANITY check infrastructure. The feature bits are classified into following 3 types depending on the implication of the possible values. This information is used to decide the safe value for a feature. LOWER_SAFE - The smaller value is safer HIGHER_SAFE - The bigger value is safer EXACT - We can't decide between the two, so a predefined safe_value is used. This infrastructure will be later used to make better decisions for: - Kernel features (e.g, KVM, Debug) - SANITY Check - CPU capability - ELF HWCAP - Exposing CPU Feature register to userspace. Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Tested-by: Dave Martin <Dave.Martin@arm.com> [catalin.marinas@arm.com: whitespace fix] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-21arm64: Move /proc/cpuinfo handling codeSuzuki K. Poulose
This patch moves the /proc/cpuinfo handling code: arch/arm64/kernel/{setup.c to cpuinfo.c} No functional changes Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Tested-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-21arm64: Move mixed endian support detectionSuzuki K. Poulose
Move the mixed endian support detection code to cpufeature.c from cpuinfo.c. This also moves the update_cpu_features() used by mixed endian detection code, which will get more functionality. Also moves the ID register field shifts to asm/sysreg.h, where all the useful definitions will end up in later patches. Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Tested-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-03-30arm64: Extract feature parsing code from cpu_errata.cMarc Zyngier
As we detect more architectural features at runtime, it makes sense to reuse the existing framework whilst avoiding to call a feature an erratum... This patch extract the core capability parsing, moves it into a new file (cpufeature.c), and let the CPU errata detection code use it. Reviewed-by: Andre Przywara <andre.przywara@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-01-23arm64: Track system support for mixed endian EL0Suzuki K. Poulose
This patch keeps track of the mixed endian EL0 support across the system and provides helper functions to export it. The status is a boolean indicating whether all the CPUs on the system supports mixed endian at EL0. Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-01-15arm64: kernel: add support for cpu cache informationSudeep Holla
This patch adds support for cacheinfo on ARM64. On ARMv8, the cache hierarchy can be identified through Cache Level ID (CLIDR) register while the cache geometry is provided by Cache Size ID (CCSIDR) register. Since the architecture doesn't provide any way of detecting the cpus sharing particular cache, device tree is used for the same purpose. Signed-off-by: Sudeep Holla <sudeep.holla@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-01-07arm64: sanity checks: add missing AArch32 registersMark Rutland
We don't currently check a number of registers exposed to AArch32 guests (MVFR{0,1,2}_EL1 and ID_DFR0_EL1), despite the fact these describe AArch32 feature support exposed to userspace and KVM guests similarly to AArch64 registers which we do check. We do not expect these registers to vary across a set of CPUs. This patch adds said registers to the cpuinfo framework and sanity checks. No sanity check failures have been observed on a current ARMv8 big.LITTLE platform (Juno). Cc: Catalin Marinas <catalin.marinas@arm.com> Reported-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-25arm64: sanity checks: add ID_AA64DFR{0,1}_EL1Mark Rutland
While we currently expect self-hosted debug support to be identical across CPUs, we don't currently sanity check this. This patch adds logging of the ID_AA64DFR{0,1}_EL1 values and associated sanity checking code. It's not clear to me whether we need to check PMUVer, TraceVer, and DebugVer, as we don't currently rely on these fields at all. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-25arm64: sanity checks: add missing newline to printMark Rutland
A missing newline in the WARN_TAINT_ONCE string results in ugly and somewhat difficult to read output in the case of a sanity check failure, as the next print does not appear on a new line: Unsupported CPU feature variation.Modules linked in: This patch adds the missing newline, fixing the output formatting. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-25arm64: sanity checks: ignore ID_MMFR0.AuxRegMark Rutland
It seems that Cortex-A53 r0p4 added support for AIFSR and ADFSR, and ID_MMFR0.AuxReg has been updated accordingly to report this fact. As Cortex-A53 could be paired with CPUs which do not implement these registers (e.g. all current revisions of Cortex-A57), this may trigger a sanity check failure at boot. The AuxReg value describes the availability of the ACTLR, AIFSR, and ADFSR registers, which are only of use to 32-bit guest OSs, and have IMPLEMENTATION DEFINED contents. Given the nature of these registers it is likely that KVM will need to trap accesses regardless of whether the CPUs are heterogeneous. This patch masks out the ID_MMFR0.AuxReg value from the sanity checks, preventing spurious warnings at boot time. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reported-by: Andre Przywara <andre.przywara@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Cc: Peter Maydell <peter.maydell@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-25arm64: detect silicon revisions and set cap bits accordinglyAndre Przywara
After each CPU has been started, we iterate through a list of CPU features or bugs to detect CPUs which need (or could benefit from) kernel code patches. For each feature/bug there is a function which checks if that particular CPU is affected. We will later provide some more generic functions for common things like testing for certain MIDR ranges. We do this for every CPU to cover big.LITTLE systems properly as well. If a certain feature/bug has been detected, the capability bit will be set, so that later the call to apply_alternatives() will trigger the actual code patching. Signed-off-by: Andre Przywara <andre.przywara@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-09-08arm64: don't flag non-aliasing VIPT I-caches as aliasingArd Biesheuvel
VIPT caches are non-aliasing if the index is derived from address bits that are always equal between VA and PA. Classifying these as aliasing results in unnecessary flushing which may hurt performance. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-09-08arm64: add helper functions to read I-cache attributesArd Biesheuvel
This adds helper functions and #defines to <asm/cachetype.h> to read the line size and the number of sets from the level 1 instruction cache. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-08-18arm64: fix typo in I-cache policy detectionArd Biesheuvel
This removes an unfortunately placed semi-colon resulting in all instruction caches being classified as AIVIVT. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-08-01arm64: add newline to I-cache policy stringMark Rutland
Due to a missing newline in the I-cache policy detection log output, it's possible to get some ratehr unfortunate output at boot time: CPU1: Booted secondary processor Detected VIPT I-cache on CPU1CPU2: Booted secondary processor Detected VIPT I-cache on CPU2CPU3: Booted secondary processor Detected VIPT I-cache on CPU3CPU4: Booted secondary processor Detected PIPT I-cache on CPU4CPU5: Booted secondary processor Detected PIPT I-cache on CPU5Brought up 6 CPUs SMP: Total of 6 processors activated. This patch adds the missing newline to the format string, cleaning up the output. Fixes: 59ccc0d41b7a ("arm64: cachetype: report weakest cache policy") Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-07-18arm64: add runtime system sanity checksMark Rutland
Unexpected variation in certain system register values across CPUs is an indicator of potential problems with a system. The kernel expects CPUs to be mostly identical in terms of supported features, even in systems with heterogeneous CPUs, with uniform instruction set support being critical for the correct operation of userspace. To help detect issues early where hardware violates the expectations of the kernel, this patch adds simple runtime sanity checks on important ID registers in the bring up path of each CPU. Where CPUs are fundamentally mismatched, set TAINT_CPU_OUT_OF_SPEC. Given that the kernel assumes CPUs are identical feature wise, let's not pretend that we expect such configurations to work. Supporting such configurations would require massive rework, and hopefully they will never exist. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-07-18arm64: cachetype: report weakest cache policyMark Rutland
In big.LITTLE systems, the I-cache policy may differ across CPUs, and thus we must always meet the most stringent maintenance requirements of any I-cache in the system when performing maintenance to ensure correctness. Unfortunately this requirement is not met as we always look at the current CPU's cache type register to determine the maintenance requirements. This patch causes the I-cache policy of all CPUs to be taken into account for icache_is_aliasing and icache_is_aivivt. If any I-cache in the system is aliasing or AIVIVT, the respective function will return true. At boot each CPU may set flags to identify that at least one I-cache in the system is aliasing and/or AIVIVT. The now unused and potentially misleading icache_policy function is removed. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-07-18arm64: cpuinfo: record cpu system register valuesMark Rutland
Several kernel subsystems need to know details about CPU system register values, sometimes for CPUs other than that they are executing on. Rather than hard-coding system register accesses and cross-calls for these cases, this patch adds logic to record various system register values at boot-time. This may be used for feature reporting, firmware bug detection, etc. Separate hooks are added for the boot and hotplug paths to enable one-time intialisation and cold/warm boot value mismatch detection in later patches. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>