From 552ae76face5584085845646c5f57e10c1a4ebdc Mon Sep 17 00:00:00 2001 From: Marc Zyngier Date: Sat, 22 Dec 2018 12:00:10 +0000 Subject: [PATCH] arm64: Detect the ARMv8.4 TTL feature In order to reduce the cost of TLB invalidation, the ARMv8.4 TTL feature allows TLBs to be issued with a level allowing for quicker invalidation. Let's detect the feature for now. Further patches will implement its actual usage. Reviewed-by : Suzuki K Polose Reviewed-by: Catalin Marinas Signed-off-by: Marc Zyngier --- arch/arm64/include/asm/cpucaps.h | 3 ++- arch/arm64/include/asm/sysreg.h | 1 + arch/arm64/kernel/cpufeature.c | 11 +++++++++++ 3 files changed, 14 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/cpucaps.h b/arch/arm64/include/asm/cpucaps.h index d7b3bb0cb180..d44ba903d11d 100644 --- a/arch/arm64/include/asm/cpucaps.h +++ b/arch/arm64/include/asm/cpucaps.h @@ -62,7 +62,8 @@ #define ARM64_HAS_GENERIC_AUTH 52 #define ARM64_HAS_32BIT_EL1 53 #define ARM64_BTI 54 +#define ARM64_HAS_ARMv8_4_TTL 55 -#define ARM64_NCAPS 55 +#define ARM64_NCAPS 56 #endif /* __ASM_CPUCAPS_H */ diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h index 463175f80341..8c209aa17273 100644 --- a/arch/arm64/include/asm/sysreg.h +++ b/arch/arm64/include/asm/sysreg.h @@ -746,6 +746,7 @@ /* id_aa64mmfr2 */ #define ID_AA64MMFR2_E0PD_SHIFT 60 +#define ID_AA64MMFR2_TTL_SHIFT 48 #define ID_AA64MMFR2_FWB_SHIFT 40 #define ID_AA64MMFR2_AT_SHIFT 32 #define ID_AA64MMFR2_LVA_SHIFT 16 diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 9f63053a63a9..e877f56ff1ab 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -323,6 +323,7 @@ static const struct arm64_ftr_bits ftr_id_aa64mmfr1[] = { static const struct arm64_ftr_bits ftr_id_aa64mmfr2[] = { ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_E0PD_SHIFT, 4, 0), + ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_TTL_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_FWB_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_AT_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR2_LVA_SHIFT, 4, 0), @@ -1882,6 +1883,16 @@ static const struct arm64_cpu_capabilities arm64_features[] = { .matches = has_cpuid_feature, .cpu_enable = cpu_has_fwb, }, + { + .desc = "ARMv8.4 Translation Table Level", + .type = ARM64_CPUCAP_SYSTEM_FEATURE, + .capability = ARM64_HAS_ARMv8_4_TTL, + .sys_reg = SYS_ID_AA64MMFR2_EL1, + .sign = FTR_UNSIGNED, + .field_pos = ID_AA64MMFR2_TTL_SHIFT, + .min_field_value = 1, + .matches = has_cpuid_feature, + }, #ifdef CONFIG_ARM64_HW_AFDBM { /* -- GitLab