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2017-12-12arm64: Add software workaround for Falkor erratum 1041Shanker Donthineni
The ARM architecture defines the memory locations that are permitted to be accessed as the result of a speculative instruction fetch from an exception level for which all stages of translation are disabled. Specifically, the core is permitted to speculatively fetch from the 4KB region containing the current program counter 4K and next 4K. When translation is changed from enabled to disabled for the running exception level (SCTLR_ELn[M] changed from a value of 1 to 0), the Falkor core may errantly speculatively access memory locations outside of the 4KB region permitted by the architecture. The errant memory access may lead to one of the following unexpected behaviors. 1) A System Error Interrupt (SEI) being raised by the Falkor core due to the errant memory access attempting to access a region of memory that is protected by a slave-side memory protection unit. 2) Unpredictable device behavior due to a speculative read from device memory. This behavior may only occur if the instruction cache is disabled prior to or coincident with translation being changed from enabled to disabled. The conditions leading to this erratum will not occur when either of the following occur: 1) A higher exception level disables translation of a lower exception level (e.g. EL2 changing SCTLR_EL1[M] from a value of 1 to 0). 2) An exception level disabling its stage-1 translation if its stage-2 translation is enabled (e.g. EL1 changing SCTLR_EL1[M] from a value of 1 to 0 when HCR_EL2[VM] has a value of 1). To avoid the errant behavior, software must execute an ISB immediately prior to executing the MSR that will change SCTLR_ELn[M] from 1 to 0. Signed-off-by: Shanker Donthineni <shankerd@codeaurora.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
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 ...
2017-11-03arm64/sve: Add documentationDave Martin
This patch adds basic documentation of the user/kernel interface provided by the for SVE. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Alan Hayward <alan.hayward@arm.com> Cc: Alex Bennée <alex.bennee@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Michael Kerrisk <mtk.manpages@gmail.com> Cc: Szabolcs Nagy <szabolcs.nagy@arm.com> Cc: linux-api@vger.kernel.org Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-11-03arm64/sve: Detect SVE and activate runtime supportDave Martin
This patch enables detection of hardware SVE support via the cpufeatures framework, and reports its presence to the kernel and userspace via the new ARM64_SVE cpucap and HWCAP_SVE hwcap respectively. Userspace can also detect SVE using ID_AA64PFR0_EL1, using the cpufeatures MRS emulation. When running on hardware that supports SVE, this enables runtime kernel support for SVE, and allows user tasks to execute SVE instructions and make of the of the SVE-specific user/kernel interface extensions implemented by this series. Signed-off-by: Dave Martin <Dave.Martin@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-19irqchip/gic-v3-its: Workaround HiSilicon Hip07 redistributor addressingMarc Zyngier
The ITSes on the Hip07 (as present in the Huawei D05) are broken when it comes to addressing the redistributors, and need to be explicitely told to address the VLPI page instead of the redistributor base address. So let's add yet another quirk, fixing up the target address in the command stream. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-10-11arm64: docs: describe ELF hwcapsMark Rutland
We don't document our ELF hwcaps, leaving developers to interpret them according to hearsay, guesswork, or (in exceptional cases) inspection of the current kernel code. This is less than optimal, and it would be far better if we had some definitive description of each of the ELF hwcaps that developers could refer to. This patch adds a document describing the (native) arm64 ELF hwcaps. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Dave Martin <Dave.Martin@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Mark Rutland <mark.rutland@arm.com> [ Updated new hwcap entries in the document ] Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-11arm64: Expose support for optional ARMv8-A featuresSuzuki K Poulose
ARMv8-A adds a few optional features for ARMv8.2 and ARMv8.3. Expose them to the userspace via HWCAPs and mrs emulation. SHA2-512 - Instruction support for SHA512 Hash algorithm (e.g SHA512H, SHA512H2, SHA512U0, SHA512SU1) SHA3 - SHA3 crypto instructions (EOR3, RAX1, XAR, BCAX). SM3 - Instruction support for Chinese cryptography algorithm SM3 SM4 - Instruction support for Chinese cryptography algorithm SM4 DP - Dot Product instructions (UDOT, SDOT). Cc: Will Deacon <will.deacon@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Dave Martin <dave.martin@arm.com> Cc: Marc Zyngier <marc.zyngier@arm.com> Reviewed-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>
2017-10-02arm64: fix documentation on kernel pages mappings to HYP VAYury Norov
The Documentation/arm64/memory.txt says: When using KVM, the hypervisor maps kernel pages in EL2, at a fixed offset from the kernel VA (top 24bits of the kernel VA set to zero): In fact, kernel addresses are transleted to HYP with kern_hyp_va macro, which has more options, and none of them assumes clearing of top 24bits of the kernel VA. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Yury Norov <ynorov@caviumnetworks.com> [will: removed gory details] Signed-off-by: Will Deacon <will.deacon@arm.com>
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>
2017-07-12Merge tag 'iommu-updates-v4.13' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu Pull IOMMU updates from Joerg Roedel: "This update comes with: - Support for lockless operation in the ARM io-pgtable code. This is an important step to solve the scalability problems in the common dma-iommu code for ARM - Some Errata workarounds for ARM SMMU implemenations - Rewrite of the deferred IO/TLB flush code in the AMD IOMMU driver. The code suffered from very high flush rates, with the new implementation the flush rate is down to ~1% of what it was before - Support for amd_iommu=off when booting with kexec. The problem here was that the IOMMU driver bailed out early without disabling the iommu hardware, if it was enabled in the old kernel - The Rockchip IOMMU driver is now available on ARM64 - Align the return value of the iommu_ops->device_group call-backs to not miss error values - Preempt-disable optimizations in the Intel VT-d and common IOVA code to help Linux-RT - Various other small cleanups and fixes" * tag 'iommu-updates-v4.13' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (60 commits) iommu/vt-d: Constify intel_dma_ops iommu: Warn once when device_group callback returns NULL iommu/omap: Return ERR_PTR in device_group call-back iommu: Return ERR_PTR() values from device_group call-backs iommu/s390: Use iommu_group_get_for_dev() in s390_iommu_add_device() iommu/vt-d: Don't disable preemption while accessing deferred_flush() iommu/iova: Don't disable preempt around this_cpu_ptr() iommu/arm-smmu-v3: Add workaround for Cavium ThunderX2 erratum #126 iommu/arm-smmu-v3: Enable ACPI based HiSilicon CMD_PREFETCH quirk(erratum 161010701) iommu/arm-smmu-v3: Add workaround for Cavium ThunderX2 erratum #74 ACPI/IORT: Fixup SMMUv3 resource size for Cavium ThunderX2 SMMUv3 model iommu/arm-smmu-v3, acpi: Add temporary Cavium SMMU-V3 IORT model number definitions iommu/io-pgtable-arm: Use dma_wmb() instead of wmb() when publishing table iommu/io-pgtable: depend on !GENERIC_ATOMIC64 when using COMPILE_TEST with LPAE iommu/arm-smmu-v3: Remove io-pgtable spinlock iommu/arm-smmu: Remove io-pgtable spinlock iommu/io-pgtable-arm-v7s: Support lockless operation iommu/io-pgtable-arm: Support lockless operation iommu/io-pgtable: Introduce explicit coherency iommu/io-pgtable-arm-v7s: Refactor split_blk_unmap ...
2017-06-23iommu/arm-smmu-v3: Add workaround for Cavium ThunderX2 erratum #126Geetha Sowjanya
Cavium ThunderX2 SMMU doesn't support MSI and also doesn't have unique irq lines for gerror, eventq and cmdq-sync. New named irq "combined" is set as a errata workaround, which allows to share the irq line by register single irq handler for all the interrupts. Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Signed-off-by: Geetha sowjanya <gakula@caviumnetworks.com> [will: reworked irq equality checking and added SPI check] Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-06-23iommu/arm-smmu-v3: Enable ACPI based HiSilicon CMD_PREFETCH quirk(erratum ↵shameer
161010701) HiSilicon SMMUv3 on Hip06/Hip07 platforms doesn't support CMD_PREFETCH command. The dt based support for this quirk is already present in the driver(hisilicon,broken-prefetch-cmd). This adds ACPI support for the quirk using the IORT smmu model number. Signed-off-by: shameer <shameerali.kolothum.thodi@huawei.com> Signed-off-by: hanjun <guohanjun@huawei.com> [will: rewrote patch] Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-06-23iommu/arm-smmu-v3: Add workaround for Cavium ThunderX2 erratum #74Linu Cherian
Cavium ThunderX2 SMMU implementation doesn't support page 1 register space and PAGE0_REGS_ONLY option is enabled as an errata workaround. This option when turned on, replaces all page 1 offsets used for EVTQ_PROD/CONS, PRIQ_PROD/CONS register access with page 0 offsets. SMMU resource size checks are now based on SMMU option PAGE0_REGS_ONLY, since resource size can be either 64k/128k. For this, arm_smmu_device_dt_probe/acpi_probe has been moved before platform_get_resource call, so that SMMU options are set beforehand. Signed-off-by: Linu Cherian <linu.cherian@cavium.com> Signed-off-by: Geetha Sowjanya <geethasowjanya.akula@cavium.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-06-15arm64: Add workaround for Cavium Thunder erratum 30115David Daney
Some Cavium Thunder CPUs suffer a problem where a KVM guest may inadvertently cause the host kernel to quit receiving interrupts. Use the Group-0/1 trapping in order to deal with it. [maz]: Adapted patch to the Group-0/1 trapping, reworked commit log Tested-by: Alexander Graf <agraf@suse.de> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Signed-off-by: David Daney <david.daney@cavium.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <cdall@linaro.org>
2017-05-09arm64: documentation: document tagged pointer stack constraintsKristina Martsenko
Some kernel features don't currently work if a task puts a non-zero address tag in its stack pointer, frame pointer, or frame record entries (FP, LR). For example, with a tagged stack pointer, the kernel can't deliver signals to the process, and the task is killed instead. As another example, with a tagged frame pointer or frame records, perf fails to generate call graphs or resolve symbols. For now, just document these limitations, instead of finding and fixing everything that doesn't work, as it's not known if anyone needs to use tags in these places anyway. In addition, as requested by Dave Martin, generalize the limitations into a general kernel address tag policy, and refactor tagged-pointers.txt to include it. Fixes: d50240a5f6ce ("arm64: mm: permit use of tagged pointers at EL0") Cc: <stable@vger.kernel.org> # 3.12.x- Reviewed-by: Dave Martin <Dave.Martin@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-04-07Merge tag 'arch-timer-errata-prereq' of ↵Catalin Marinas
git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into for-next/core Pre-requisites for the arch timer errata workarounds: - Allow checking of a CPU-local erratum - Add CNTVCT_EL0 trap handler - Define Cortex-A73 MIDR - Allow an erratum to be match for all revisions of a core - Add capability to advertise Cortex-A73 erratum 858921 * tag 'arch-timer-errata-prereq' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms: arm64: cpu_errata: Add capability to advertise Cortex-A73 erratum 858921 arm64: cpu_errata: Allow an erratum to be match for all revisions of a core arm64: Define Cortex-A73 MIDR arm64: Add CNTVCT_EL0 trap handler arm64: Allow checking of a CPU-local erratum
2017-04-07arm64: cpu_errata: Add capability to advertise Cortex-A73 erratum 858921Marc Zyngier
In order to work around Cortex-A73 erratum 858921 in a subsequent patch, add the required capability that advertise the erratum. As the configuration option it depends on is not present yet, this has no immediate effect. Acked-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@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>
2017-03-07irqchip/gicv3-its: Add workaround for QDF2400 ITS erratum 0065Shanker Donthineni
On Qualcomm Datacenter Technologies QDF2400 SoCs, the ITS hardware implementation uses 16Bytes for Interrupt Translation Entry (ITE), but reports an incorrect value of 8Bytes in GITS_TYPER.ITTE_size. It might cause kernel memory corruption depending on the number of MSI(x) that are configured and the amount of memory that has been allocated for ITEs in its_create_device(). This patch fixes the potential memory corruption by setting the correct ITE size to 16Bytes. Cc: stable@vger.kernel.org Signed-off-by: Shanker Donthineni <shankerd@codeaurora.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-02-10arm64: Work around Falkor erratum 1003Christopher Covington
The Qualcomm Datacenter Technologies Falkor v1 CPU may allocate TLB entries using an incorrect ASID when TTBRx_EL1 is being updated. When the erratum is triggered, page table entries using the new translation table base address (BADDR) will be allocated into the TLB using the old ASID. All circumstances leading to the incorrect ASID being cached in the TLB arise when software writes TTBRx_EL1[ASID] and TTBRx_EL1[BADDR], a memory operation is in the process of performing a translation using the specific TTBRx_EL1 being written, and the memory operation uses a translation table descriptor designated as non-global. EL2 and EL3 code changing the EL1&0 ASID is not subject to this erratum because hardware is prohibited from performing translations from an out-of-context translation regime. Consider the following pseudo code. write new BADDR and ASID values to TTBRx_EL1 Replacing the above sequence with the one below will ensure that no TLB entries with an incorrect ASID are used by software. write reserved value to TTBRx_EL1[ASID] ISB write new value to TTBRx_EL1[BADDR] ISB write new value to TTBRx_EL1[ASID] ISB When the above sequence is used, page table entries using the new BADDR value may still be incorrectly allocated into the TLB using the reserved ASID. Yet this will not reduce functionality, since TLB entries incorrectly tagged with the reserved ASID will never be hit by a later instruction. Based on work by Shanker Donthineni <shankerd@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Christopher Covington <cov@codeaurora.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-02-09arm64: arch_timer: document Hisilicon erratum 161010101Ding Tianhong
Now that we have a workaround for Hisilicon erratum 161010101, notes this in the arm64 silicon-errata document. The new config option is too long to fit in the existing kconfig column, so this is widened to accomodate it. At the same time, an existing whitespace error is corrected, and the existing pattern of a line space between vendors is enforced for recent additions. Signed-off-by: Ding Tianhong <dingtianhong@huawei.com> [Mark: split patch, reword commit message, rework table] Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-02-01arm64: Work around Falkor erratum 1009Christopher Covington
During a TLB invalidate sequence targeting the inner shareable domain, Falkor may prematurely complete the DSB before all loads and stores using the old translation are observed. Instruction fetches are not subject to the conditions of this erratum. If the original code sequence includes multiple TLB invalidate instructions followed by a single DSB, onle one of the TLB instructions needs to be repeated to work around this erratum. While the erratum only applies to cases in which the TLBI specifies the inner-shareable domain (*IS form of TLBI) and the DSB is ISH form or stronger (OSH, SYS), this changes applies the workaround overabundantly-- to local TLBI, DSB NSH sequences as well--for simplicity. Based on work by Shanker Donthineni <shankerd@codeaurora.org> Signed-off-by: Christopher Covington <cov@codeaurora.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-01-12arm64: Documentation - Expose CPU feature registersSuzuki K Poulose
Documentation for the infrastructure to expose CPU feature register by emulating MRS. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Dave Martin <dave.martin@arm.com> Reviewed-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>
2016-10-03Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Will Deacon: "It's a bit all over the place this time with no "killer feature" to speak of. Support for mismatched cache line sizes should help people seeing whacky JIT failures on some SoCs, and the big.LITTLE perf updates have been a long time coming, but a lot of the changes here are cleanups. We stray outside arch/arm64 in a few areas: the arch/arm/ arch_timer workaround is acked by Russell, the DT/OF bits are acked by Rob, the arch_timer clocksource changes acked by Marc, CPU hotplug by tglx and jump_label by Peter (all CC'd). Summary: - Support for execute-only page permissions - Support for hibernate and DEBUG_PAGEALLOC - Support for heterogeneous systems with mismatches cache line sizes - Errata workarounds (A53 843419 update and QorIQ A-008585 timer bug) - arm64 PMU perf updates, including cpumasks for heterogeneous systems - Set UTS_MACHINE for building rpm packages - Yet another head.S tidy-up - Some cleanups and refactoring, particularly in the NUMA code - Lots of random, non-critical fixes across the board" * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (100 commits) arm64: tlbflush.h: add __tlbi() macro arm64: Kconfig: remove SMP dependence for NUMA arm64: Kconfig: select OF/ACPI_NUMA under NUMA config arm64: fix dump_backtrace/unwind_frame with NULL tsk arm/arm64: arch_timer: Use archdata to indicate vdso suitability arm64: arch_timer: Work around QorIQ Erratum A-008585 arm64: arch_timer: Add device tree binding for A-008585 erratum arm64: Correctly bounds check virt_addr_valid arm64: migrate exception table users off module.h and onto extable.h arm64: pmu: Hoist pmu platform device name arm64: pmu: Probe default hw/cache counters arm64: pmu: add fallback probe table MAINTAINERS: Update ARM PMU PROFILING AND DEBUGGING entry arm64: Improve kprobes test for atomic sequence arm64/kvm: use alternative auto-nop arm64: use alternative auto-nop arm64: alternative: add auto-nop infrastructure arm64: lse: convert lse alternatives NOP padding to use __nops arm64: barriers: introduce nops and __nops macros for NOP sequences arm64: sysreg: replace open-coded mrs_s/msr_s with {read,write}_sysreg_s ...
2016-09-23arm64: arch_timer: Work around QorIQ Erratum A-008585Scott Wood
Erratum A-008585 says that the ARM generic timer counter "has the potential to contain an erroneous value for a small number of core clock cycles every time the timer value changes". Accesses to TVAL (both read and write) are also affected due to the implicit counter read. Accesses to CVAL are not affected. The workaround is to reread TVAL and count registers until successive reads return the same value. Writes to TVAL are replaced with an equivalent write to CVAL. The workaround is to reread TVAL and count registers until successive reads return the same value, and when writing TVAL to retry until counter reads before and after the write return the same value. The workaround is enabled if the fsl,erratum-a008585 property is found in the timer node in the device tree. This can be overridden with the clocksource.arm_arch_timer.fsl-a008585 boot parameter, which allows KVM users to enable the workaround until a mechanism is implemented to automatically communicate this information. This erratum can be found on LS1043A and LS2080A. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Scott Wood <oss@buserror.net> [will: renamed read macro to reflect that it's not usually unstable] Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-08-17arm64: Document workaround for Cortex-A72 erratum #853709Marc Zyngier
We already have a workaround for Cortex-A57 erratum #852523, but Cortex-A72 r0p0 to r0p2 do suffer from the same issue (known as erratum #853709). Let's document the fact that we already handle this. Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-06-21ARM64: ACPI: Update documentation for latest specification versionAl Stone
The ACPI 6.1 specification was recently released at the end of January 2016, but the arm64 kernel documentation for the use of ACPI was written for the 5.1 version of the spec. There were significant additions to the spec that had not yet been mentioned -- for example, the 6.0 mechanisms added to make it easier to define processors and low power idle states, as well as the 6.1 addition allowing regular interrupts (not just from GPIO) be used to signal ACPI general purpose events. This patch reflects going back through and examining the specs in detail and updating content appropriately. Whilst there, a few odds and ends of typos were caught as well. This brings the documentation up to date with ACPI 6.1 for arm64. Signed-off-by: Al Stone <al.stone@linaro.org> Acked-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org> Reviewed-by: Roy Franz <roy.franz@hpe.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-06-02irqchip/gicv3-its: numa: Enable workaround for Cavium thunderx erratum 23144Ganapatrao Kulkarni
The erratum fixes the hang of ITS SYNC command by avoiding inter node io and collections/cpu mapping on thunderx dual-socket platform. This fix is only applicable for Cavium's ThunderX dual-socket platform. Reviewed-by: Robert Richter <rrichter@cavium.com> Signed-off-by: Ganapatrao Kulkarni <gkulkarni@caviumnetworks.com> Signed-off-by: Robert Richter <rrichter@cavium.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-05-19Merge tag 'iommu-updates-v4.7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu Pull IOMMU updates from Joerg Roedel: "The updates include: - rate limiting for the VT-d fault handler - remove statistics code from the AMD IOMMU driver. It is unused and should be replaced by something more generic if needed - per-domain pagesize-bitmaps in IOMMU core code to support systems with different types of IOMMUs - support for ACPI devices in the AMD IOMMU driver - 4GB mode support for Mediatek IOMMU driver - ARM-SMMU updates from Will Deacon: - support for 64k pages with SMMUv1 implementations (e.g MMU-401) - remove open-coded 64-bit MMIO accessors - initial support for 16-bit VMIDs, as supported by some ThunderX SMMU implementations - a couple of errata workarounds for silicon in the field - various fixes here and there" * tag 'iommu-updates-v4.7' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (44 commits) iommu/arm-smmu: Use per-domain page sizes. iommu/amd: Remove statistics code iommu/dma: Finish optimising higher-order allocations iommu: Allow selecting page sizes per domain iommu: of: enforce const-ness of struct iommu_ops iommu: remove unused priv field from struct iommu_ops iommu/dma: Implement scatterlist segment merging iommu/arm-smmu: Clear cache lock bit of ACR iommu/arm-smmu: Support SMMUv1 64KB supplement iommu/arm-smmu: Decouple context format from kernel config iommu/arm-smmu: Tidy up 64-bit/atomic I/O accesses io-64-nonatomic: Add relaxed accessor variants iommu/arm-smmu: Work around MMU-500 prefetch errata iommu/arm-smmu: Convert ThunderX workaround to new method iommu/arm-smmu: Differentiate specific implementations iommu/arm-smmu: Workaround for ThunderX erratum #27704 iommu/arm-smmu: Add support for 16 bit VMID iommu/amd: Move get_device_id() and friends to beginning of file iommu/amd: Don't use IS_ERR_VALUE to check integer values iommu/amd: Signedness bug in acpihid_device_group() ...
2016-05-03iommu/arm-smmu: Work around MMU-500 prefetch errataRobin Murphy
MMU-500 erratum #841119 is tickled by a particular set of circumstances interacting with the next-page prefetcher. Since said prefetcher is quite dumb and actually detrimental to performance in some cases (by causing unwanted TLB evictions for non-sequential access patterns), we lose very little by turning it off, and what we gain is a guarantee that the erratum is never hit. As a bonus, the same workaround will also prevent erratum #826419 once v7 short descriptor support is implemented. CC: Catalin Marinas <catalin.marinas@arm.com> CC: Will Deacon <will.deacon@arm.com> Signed-off-by: Robin Murphy <robin.murphy@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-05-03iommu/arm-smmu: Workaround for ThunderX erratum #27704Tirumalesh Chalamarla
Due to erratum #27704, the CN88xx SMMUv2 implementation supports only shared ASID and VMID numberspaces. This patch ensures that ASID and VMIDs are unique across all SMMU instances on affected Cavium systems. Signed-off-by: Tirumalesh Chalamarla <tchalamarla@caviumnetworks.com> Signed-off-by: Akula Geethasowjanya <Geethasowjanya.Akula@caviumnetworks.com> [will: commit message, comments and formatting] Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-04-14arm64: add the initrd region to the linear mapping explicitlyArd Biesheuvel
Instead of going out of our way to relocate the initrd if it turns out to occupy memory that is not covered by the linear mapping, just add the initrd to the linear mapping. This puts the burden on the bootloader to pass initrd= and mem= options that are mutually consistent. Note that, since the placement of the linear region in the PA space is also dependent on the placement of the kernel Image, which may reside anywhere in memory, we may still end up with a situation where the initrd and the kernel Image are simply too far apart to be covered by the linear region. Since we now leave it up to the bootloader to pass the initrd in memory that is guaranteed to be accessible by the kernel, add a mention of this to the arm64 boot protocol specification as well. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2016-02-26arm64: Add workaround for Cavium erratum 27456Andrew Pinski
On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI instructions may cause the icache to become corrupted if it contains data for a non-current ASID. This patch implements the workaround (which invalidates the local icache when switching the mm) by using code patching. Signed-off-by: Andrew Pinski <apinski@cavium.com> Signed-off-by: David Daney <david.daney@cavium.com> Reviewed-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-02-18arm64: allow kernel Image to be loaded anywhere in physical memoryArd Biesheuvel
This relaxes the kernel Image placement requirements, so that it may be placed at any 2 MB aligned offset in physical memory. This is accomplished by ignoring PHYS_OFFSET when installing memblocks, and accounting for the apparent virtual offset of the kernel Image. As a result, virtual address references below PAGE_OFFSET are correctly mapped onto physical references into the kernel Image regardless of where it sits in memory. Special care needs to be taken for dealing with memory limits passed via mem=, since the generic implementation clips memory top down, which may clip the kernel image itself if it is loaded high up in memory. To deal with this case, we simply add back the memory covering the kernel image, which may result in more memory to be retained than was passed as a mem= parameter. Since mem= should not be considered a production feature, a panic notifier handler is installed that dumps the memory limit at panic time if one was set. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-12-11arm64: Documentation: add list of software workarounds for errataWill Deacon
It's not immediately obvious which hardware errata are worked around in the Linux kernel for an arbitrary kernel tree, so add a file to keep track of what we're working around. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-11-04Merge tag 'arm64-upstream' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux Pull arm64 updates from Catalin Marinas: - "genirq: Introduce generic irq migration for cpu hotunplugged" patch merged from tip/irq/for-arm to allow the arm64-specific part to be upstreamed via the arm64 tree - CPU feature detection reworked to cope with heterogeneous systems where CPUs may not have exactly the same features. The features reported by the kernel via internal data structures or ELF_HWCAP are delayed until all the CPUs are up (and before user space starts) - Support for 16KB pages, with the additional bonus of a 36-bit VA space, though the latter only depending on EXPERT - Implement native {relaxed, acquire, release} atomics for arm64 - New ASID allocation algorithm which avoids IPI on roll-over, together with TLB invalidation optimisations (using local vs global where feasible) - KASan support for arm64 - EFI_STUB clean-up and isolation for the kernel proper (required by KASan) - copy_{to,from,in}_user optimisations (sharing the memcpy template) - perf: moving arm64 to the arm32/64 shared PMU framework - L1_CACHE_BYTES increased to 128 to accommodate Cavium hardware - Support for the contiguous PTE hint on kernel mapping (16 consecutive entries may be able to use a single TLB entry) - Generic CONFIG_HZ now used on arm64 - defconfig updates * tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (91 commits) arm64/efi: fix libstub build under CONFIG_MODVERSIONS ARM64: Enable multi-core scheduler support by default arm64/efi: move arm64 specific stub C code to libstub arm64: page-align sections for DEBUG_RODATA arm64: Fix build with CONFIG_ZONE_DMA=n arm64: Fix compat register mappings arm64: Increase the max granular size arm64: remove bogus TASK_SIZE_64 check arm64: make Timer Interrupt Frequency selectable arm64/mm: use PAGE_ALIGNED instead of IS_ALIGNED arm64: cachetype: fix definitions of ICACHEF_* flags arm64: cpufeature: declare enable_cpu_capabilities as static genirq: Make the cpuhotplug migration code less noisy arm64: Constify hwcap name string arrays arm64/kvm: Make use of the system wide safe values arm64/debug: Make use of the system wide safe value arm64: Move FP/ASIMD hwcap handling to common code arm64/HWCAP: Use system wide safe values arm64/capabilities: Make use of system wide safe value arm64: Delay cpu feature capability checks ...
2015-10-19arm64: Add page size to the kernel image headerArd Biesheuvel
This patch adds the page size to the arm64 kernel image header so that one can infer the PAGESIZE used by the kernel. This will be helpful to diagnose failures to boot the kernel with page size not supported by the CPU. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-10-09arm64: Update booting requirements for GICv3 in GICv2 modeMarc Zyngier
The current requirements do not describe the case where a GICv3 system gets booted with system register access disabled, and expect the kernel to drive GICv3 in GICv2 mode. Describe the expected settings for that particular case. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-07-29arm64/Documentation: clarify wording regarding memory below the ImageArd Biesheuvel
Clarify that the memory below the start of the image but inside the region covered by the linear mapping has no special significance to the kernel, and may be used by the firmware provided that it is marked as reserved. Also, fix up some whitespace errors. Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-06-02arm64: use fixmap region for permanent FDT mappingArd Biesheuvel
Currently, the FDT blob needs to be in the same 512 MB region as the kernel, so that it can be mapped into the kernel virtual memory space very early on using a minimal set of statically allocated translation tables. Now that we have early fixmap support, we can relax this restriction, by moving the permanent FDT mapping to the fixmap region instead. This way, the FDT blob may be anywhere in memory. This also moves the vetting of the FDT to mmu.c, since the early init code in head.S does not handle mapping of the FDT anymore. At the same time, fix up some comments in head.S that have gone stale. Reviewed-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2015-03-26ARM64 / ACPI: additions of ACPI documentation for arm64Al Stone
One more documentation file are also being added: A section by section review of the ACPI spec (acpi_object_usage.txt) to note recommendations and prohibitions on the use of the numerous ACPI tables and objects. This sets out the current expectations of the firmware by Linux very explicitly (or as explicitly as I can, for now). CC: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> CC: Yi Li <phoenix.liyi@huawei.com> CC: Mark Langsdorf <mlangsdo@redhat.com> CC: Ashwin Chaugule <ashwinc@codeaurora.org> Acked-by: Robert Richter <rrichter@cavium.com> Signed-off-by: Al Stone <al.stone@linaro.org> Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-03-26Documentation: ACPI for ARM64Graeme Gregory
Add documentation for the guidelines of how to use ACPI on ARM64. Reviewed-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com> Reviewed-by: Yi Li <phoenix.liyi@huawei.com> Reviewed-by: Mark Langsdorf <mlangsdo@redhat.com> Reviewed-by: Ashwin Chaugule <ashwinc@codeaurora.org> Acked-by: Robert Richter <rrichter@cavium.com> Signed-off-by: Graeme Gregory <graeme.gregory@linaro.org> Signed-off-by: Al Stone <al.stone@linaro.org> Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-01-23arm64: Emulate SETEND for AArch32 tasksSuzuki K. Poulose
Emulate deprecated 'setend' instruction for AArch32 bit tasks. setend [le/be] - Sets the endianness of EL0 On systems with CPUs which support mixed endian at EL0, the hardware support for the instruction can be enabled by setting the SCTLR_EL1.SED bit. Like the other emulated instructions it is controlled by an entry in /proc/sys/abi/. For more information see : Documentation/arm64/legacy_instructions.txt The instruction is emulated by setting/clearing the SPSR_EL1.E bit, which will be reflected in the PSTATE.E in AArch32 context. This patch also restores the native endianness for the execution of signal handlers, since the process could have changed the endianness. Note: All CPUs on the system must have mixed endian support at EL0. Once the handler is registered, hotplugging a CPU which doesn't support mixed endian, could lead to unexpected results/behavior in applications. Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Cc: Will Deacon <will.deacon@arm.com> Cc: Punit Agrawal <punit.agrawal@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-11-20arm64: Emulate CP15 Barrier instructionsPunit Agrawal
The CP15 barrier instructions (CP15ISB, CP15DSB and CP15DMB) are deprecated in the ARMv7 architecture, superseded by ISB, DSB and DMB instructions respectively. Some implementations may provide the ability to disable the CP15 barriers by disabling the CP15BEN bit in SCTLR_EL1. If not enabled, the encodings for these instructions become undefined. To support legacy software using these instructions, this patch register hooks to - * emulate CP15 barriers and warn the user about their use * toggle CP15BEN in SCTLR_EL1 Signed-off-by: Punit Agrawal <punit.agrawal@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-20arm64: Port SWP/SWPB emulation support from armPunit Agrawal
The SWP instruction was deprecated in the ARMv6 architecture. The ARMv7 multiprocessing extensions mandate that SWP/SWPB instructions are treated as undefined from reset, with the ability to enable them through the System Control Register SW bit. With ARMv8, the option to enable these instructions through System Control Register was dropped as well. To support legacy applications using these instructions, port the emulation of the SWP and SWPB instructions from the arm port to arm64. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Punit Agrawal <punit.agrawal@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-11-20arm64: Add framework for legacy instruction emulationPunit Agrawal
Typically, providing support for legacy instructions requires emulating the behaviour of instructions whose encodings have become undefined. If the instructions haven't been removed from the architecture, there maybe an option in the implementation to turn on/off the support for these instructions. Create common infrastructure to support legacy instruction emulation. In addition to emulation, also provide an option to support hardware execution when supported. The default execution mode (one of undef, emulate, hw exeuction) is dependent on the state of the instruction (deprecated or obsolete) in the architecture and can specified at the time of registering the instruction handlers. The runtime state of the emulation can be controlled by writing to individual nodes in sysctl. The expected default behaviour is documented as part of this patch. Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Punit Agrawal <punit.agrawal@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2014-10-20Documentation/arm64/memory.txt: fix typoAlex Bennée
There is no swapper_pgd_dir, it meant swapper_pg_dir. Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2014-08-05Merge tag 'kvm-arm-for-3.17' of ↵Paolo Bonzini
git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm KVM/ARM New features for 3.17 include: - Fixes and code refactoring for stage2 kvm MMU unmap_range - Support unmapping IPAs on deleting memslots for arm and arm64 - Support MMIO mappings in stage2 faults - KVM VGIC v2 emulation on GICv3 hardware - Big-Endian support for arm/arm64 (guest and host) - Debug Architecture support for arm64 (arm32 is on Christoffer's todo list) Conflicts: virt/kvm/arm/vgic.c [last minute cherry-pick from 3.17 to 3.16]