From 042446a31e3803d81c7e618dd80928dc3dce70c5 Mon Sep 17 00:00:00 2001 From: Suzuki K Poulose Date: Mon, 18 Apr 2016 10:28:36 +0100 Subject: [PATCH] arm64: cpufeature: Track 32bit EL0 support Add cpu_hwcap bit for keeping track of the support for 32bit EL0. Tested-by: Yury Norov Signed-off-by: Suzuki K Poulose Signed-off-by: Will Deacon --- arch/arm64/include/asm/cpufeature.h | 8 +++++++- arch/arm64/kernel/cpufeature.c | 9 +++++++++ 2 files changed, 16 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h index 7f64285e4ef7..ca8fb4bcfb1a 100644 --- a/arch/arm64/include/asm/cpufeature.h +++ b/arch/arm64/include/asm/cpufeature.h @@ -35,8 +35,9 @@ #define ARM64_ALT_PAN_NOT_UAO 10 #define ARM64_HAS_VIRT_HOST_EXTN 11 #define ARM64_WORKAROUND_CAVIUM_27456 12 +#define ARM64_HAS_32BIT_EL0 13 -#define ARM64_NCAPS 13 +#define ARM64_NCAPS 14 #ifndef __ASSEMBLY__ @@ -192,6 +193,11 @@ static inline bool cpu_supports_mixed_endian_el0(void) return id_aa64mmfr0_mixed_endian_el0(read_cpuid(ID_AA64MMFR0_EL1)); } +static inline bool system_supports_32bit_el0(void) +{ + return cpus_have_cap(ARM64_HAS_32BIT_EL0); +} + static inline bool system_supports_mixed_endian_el0(void) { return id_aa64mmfr0_mixed_endian_el0(read_system_reg(SYS_ID_AA64MMFR0_EL1)); diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 9097ce9244e3..40a23f24559d 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -737,6 +737,15 @@ static const struct arm64_cpu_capabilities arm64_features[] = { .capability = ARM64_HAS_VIRT_HOST_EXTN, .matches = runs_at_el2, }, + { + .desc = "32-bit EL0 Support", + .capability = ARM64_HAS_32BIT_EL0, + .matches = has_cpuid_feature, + .sys_reg = SYS_ID_AA64PFR0_EL1, + .sign = FTR_UNSIGNED, + .field_pos = ID_AA64PFR0_EL0_SHIFT, + .min_field_value = ID_AA64PFR0_EL0_32BIT_64BIT, + }, {}, }; -- 2.20.1