From 95aa6860d60881e8f08956e02199f7d65c9cbf7b Mon Sep 17 00:00:00 2001 From: Mark Brown Date: Mon, 17 Oct 2022 16:25:15 +0100 Subject: [PATCH] arm64/hwcap: Add support for FEAT_CSSC FEAT_CSSC adds a number of new instructions usable to optimise common short sequences of instructions, add a hwcap indicating that the feature is available and can be used by userspace. Signed-off-by: Mark Brown Reviewed-by: Catalin Marinas Link: https://lore.kernel.org/r/20221017152520.1039165-2-broonie@kernel.org Signed-off-by: Will Deacon --- Documentation/arm64/elf_hwcaps.rst | 3 +++ arch/arm64/include/asm/hwcap.h | 1 + arch/arm64/include/uapi/asm/hwcap.h | 1 + arch/arm64/kernel/cpufeature.c | 2 ++ arch/arm64/kernel/cpuinfo.c | 1 + arch/arm64/tools/sysreg | 7 ++++++- 6 files changed, 14 insertions(+), 1 deletion(-) diff --git a/Documentation/arm64/elf_hwcaps.rst b/Documentation/arm64/elf_hwcaps.rst index bb34287c8e01..58197e9ccb6d 100644 --- a/Documentation/arm64/elf_hwcaps.rst +++ b/Documentation/arm64/elf_hwcaps.rst @@ -275,6 +275,9 @@ HWCAP2_EBF16 HWCAP2_SVE_EBF16 Functionality implied by ID_AA64ZFR0_EL1.BF16 == 0b0010. +HWCAP2_CSSC + Functionality implied by ID_AA64ISAR2_EL1.CSSC == 0b0001. + 4. Unused AT_HWCAP bits ----------------------- diff --git a/arch/arm64/include/asm/hwcap.h b/arch/arm64/include/asm/hwcap.h index 298b386d3ebe..a0e080df9a62 100644 --- a/arch/arm64/include/asm/hwcap.h +++ b/arch/arm64/include/asm/hwcap.h @@ -120,6 +120,7 @@ #define KERNEL_HWCAP_WFXT __khwcap2_feature(WFXT) #define KERNEL_HWCAP_EBF16 __khwcap2_feature(EBF16) #define KERNEL_HWCAP_SVE_EBF16 __khwcap2_feature(SVE_EBF16) +#define KERNEL_HWCAP_CSSC __khwcap2_feature(CSSC) /* * This yields a mask that user programs can use to figure out what diff --git a/arch/arm64/include/uapi/asm/hwcap.h b/arch/arm64/include/uapi/asm/hwcap.h index 9b245da6f507..a43dddd94b4a 100644 --- a/arch/arm64/include/uapi/asm/hwcap.h +++ b/arch/arm64/include/uapi/asm/hwcap.h @@ -93,5 +93,6 @@ #define HWCAP2_WFXT (1UL << 31) #define HWCAP2_EBF16 (1UL << 32) #define HWCAP2_SVE_EBF16 (1UL << 33) +#define HWCAP2_CSSC (1UL << 34) #endif /* _UAPI__ASM_HWCAP_H */ diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 3086304652fd..23d1d6b01c1f 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -212,6 +212,7 @@ static const struct arm64_ftr_bits ftr_id_aa64isar1[] = { }; static const struct arm64_ftr_bits ftr_id_aa64isar2[] = { + ARM64_FTR_BITS(FTR_VISIBLE, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64ISAR2_EL1_CSSC_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_HIGHER_SAFE, ID_AA64ISAR2_EL1_BC_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_PTR_AUTH), FTR_STRICT, FTR_EXACT, ID_AA64ISAR2_EL1_APA3_SHIFT, 4, 0), @@ -2815,6 +2816,7 @@ static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = { #endif /* CONFIG_ARM64_MTE */ HWCAP_CAP(SYS_ID_AA64MMFR0_EL1, ID_AA64MMFR0_EL1_ECV_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_ECV), HWCAP_CAP(SYS_ID_AA64MMFR1_EL1, ID_AA64MMFR1_EL1_AFP_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_AFP), + HWCAP_CAP(SYS_ID_AA64ISAR2_EL1, ID_AA64ISAR2_EL1_CSSC_SHIFT, 4, FTR_UNSIGNED, ID_AA64ISAR2_EL1_CSSC_IMP, CAP_HWCAP, KERNEL_HWCAP_CSSC), HWCAP_CAP(SYS_ID_AA64ISAR2_EL1, ID_AA64ISAR2_EL1_RPRES_SHIFT, 4, FTR_UNSIGNED, 1, CAP_HWCAP, KERNEL_HWCAP_RPRES), HWCAP_CAP(SYS_ID_AA64ISAR2_EL1, ID_AA64ISAR2_EL1_WFxT_SHIFT, 4, FTR_UNSIGNED, ID_AA64ISAR2_EL1_WFxT_IMP, CAP_HWCAP, KERNEL_HWCAP_WFXT), #ifdef CONFIG_ARM64_SME diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c index 28d4f442b0bc..3160550c0cc9 100644 --- a/arch/arm64/kernel/cpuinfo.c +++ b/arch/arm64/kernel/cpuinfo.c @@ -116,6 +116,7 @@ static const char *const hwcap_str[] = { [KERNEL_HWCAP_WFXT] = "wfxt", [KERNEL_HWCAP_EBF16] = "ebf16", [KERNEL_HWCAP_SVE_EBF16] = "sveebf16", + [KERNEL_HWCAP_CSSC] = "cssc", }; #ifdef CONFIG_COMPAT diff --git a/arch/arm64/tools/sysreg b/arch/arm64/tools/sysreg index 384757a7eda9..629d119151bf 100644 --- a/arch/arm64/tools/sysreg +++ b/arch/arm64/tools/sysreg @@ -484,7 +484,12 @@ EndEnum EndSysreg Sysreg ID_AA64ISAR2_EL1 3 0 0 6 2 -Res0 63:28 +Res0 63:56 +Enum 55:52 CSSC + 0b0000 NI + 0b0001 IMP +EndEnum +Res0 51:28 Enum 27:24 PAC_frac 0b0000 NI 0b0001 IMP