diff options
author | Marc Zyngier <marc.zyngier@arm.com> | 2022-04-06 19:45:19 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-04-12 08:52:15 +0300 |
commit | 501d9435c7161ccc693381e4753d4b895665370a (patch) | |
tree | 3ea07643434c6786240f42f09d248c49cc3ada0f | |
parent | ba072295630fece57622f60b73756064bbaee26e (diff) | |
download | linux-501d9435c7161ccc693381e4753d4b895665370a.tar.xz |
arm64: arch_timer: Add workaround for ARM erratum 1188873
commit 95b861a4a6d94f64d5242605569218160ebacdbe upstream.
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>
Signed-off-by: James Morse <james.morse@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | arch/arm64/Kconfig | 12 | ||||
-rw-r--r-- | arch/arm64/include/asm/cpucaps.h | 3 | ||||
-rw-r--r-- | arch/arm64/include/asm/cputype.h | 2 | ||||
-rw-r--r-- | arch/arm64/kernel/cpu_errata.c | 8 | ||||
-rw-r--r-- | drivers/clocksource/arm_arch_timer.c | 15 |
5 files changed, 39 insertions, 1 deletions
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index b12275be0e13..a36595c1557b 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -441,6 +441,18 @@ config ARM64_ERRATUM_1024718 If unsure, say Y. +config ARM64_ERRATUM_1188873 + bool "Cortex-A76: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result" + default y + help + This option adds work arounds for ARM Cortex-A76 erratum 1188873 + + Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could cause + register corruption when accessing the timer registers from + AArch32 userspace. + + If unsure, say Y. + config CAVIUM_ERRATUM_22375 bool "Cavium erratum 22375, 24313" default y diff --git a/arch/arm64/include/asm/cpucaps.h b/arch/arm64/include/asm/cpucaps.h index 8c7c4b23a8b1..d4a46764c1ad 100644 --- a/arch/arm64/include/asm/cpucaps.h +++ b/arch/arm64/include/asm/cpucaps.h @@ -38,7 +38,8 @@ #define ARM64_HARDEN_BRANCH_PREDICTOR 17 #define ARM64_SSBD 18 #define ARM64_MISMATCHED_CACHE_TYPE 19 +#define ARM64_WORKAROUND_1188873 20 -#define ARM64_NCAPS 20 +#define ARM64_NCAPS 21 #endif /* __ASM_CPUCAPS_H */ diff --git a/arch/arm64/include/asm/cputype.h b/arch/arm64/include/asm/cputype.h index 61041e051acb..76b551e83f2d 100644 --- a/arch/arm64/include/asm/cputype.h +++ b/arch/arm64/include/asm/cputype.h @@ -85,6 +85,7 @@ #define ARM_CPU_PART_CORTEX_A75 0xD0A #define ARM_CPU_PART_CORTEX_A35 0xD04 #define ARM_CPU_PART_CORTEX_A55 0xD05 +#define ARM_CPU_PART_CORTEX_A76 0xD0B #define APM_CPU_PART_POTENZA 0x000 @@ -102,6 +103,7 @@ #define MIDR_CORTEX_A75 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A75) #define MIDR_CORTEX_A35 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A35) #define MIDR_CORTEX_A55 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A55) +#define MIDR_CORTEX_A76 MIDR_CPU_MODEL(ARM_CPU_IMP_ARM, ARM_CPU_PART_CORTEX_A76) #define MIDR_THUNDERX MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX) #define MIDR_THUNDERX_81XX MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX_81XX) #define MIDR_CAVIUM_THUNDERX2 MIDR_CPU_MODEL(ARM_CPU_IMP_CAVIUM, CAVIUM_CPU_PART_THUNDERX2) diff --git a/arch/arm64/kernel/cpu_errata.c b/arch/arm64/kernel/cpu_errata.c index 69c3492cb063..37cb8c23ccc6 100644 --- a/arch/arm64/kernel/cpu_errata.c +++ b/arch/arm64/kernel/cpu_errata.c @@ -533,6 +533,14 @@ const struct arm64_cpu_capabilities arm64_errata[] = { .matches = has_ssbd_mitigation, }, #endif +#ifdef CONFIG_ARM64_ERRATUM_1188873 + { + /* Cortex-A76 r0p0 to r2p0 */ + .desc = "ARM erratum 1188873", + .capability = ARM64_WORKAROUND_1188873, + ERRATA_MIDR_RANGE(MIDR_CORTEX_A76, 0, 0, 2, 0), + }, +#endif { } }; diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c index 138dbfdfb413..e70d0974470c 100644 --- a/drivers/clocksource/arm_arch_timer.c +++ b/drivers/clocksource/arm_arch_timer.c @@ -130,6 +130,13 @@ static u64 notrace fsl_a008585_read_cntvct_el0(void) } #endif +#ifdef CONFIG_ARM64_ERRATUM_1188873 +static u64 notrace arm64_1188873_read_cntvct_el0(void) +{ + return read_sysreg(cntvct_el0); +} +#endif + #ifdef CONFIG_ARM_ARCH_TIMER_OOL_WORKAROUND const struct arch_timer_erratum_workaround *timer_unstable_counter_workaround = NULL; EXPORT_SYMBOL_GPL(timer_unstable_counter_workaround); @@ -148,6 +155,14 @@ static const struct arch_timer_erratum_workaround ool_workarounds[] = { .read_cntvct_el0 = fsl_a008585_read_cntvct_el0, }, #endif +#ifdef CONFIG_ARM64_ERRATUM_1188873 + { + .match_type = ate_match_local_cap_id, + .id = (void *)ARM64_WORKAROUND_1188873, + .desc = "ARM erratum 1188873", + .read_cntvct_el0 = arm64_1188873_read_cntvct_el0, + }, +#endif }; typedef bool (*ate_match_fn_t)(const struct arch_timer_erratum_workaround *, |