Commit 86d0dd34 authored by Ard Biesheuvel's avatar Ard Biesheuvel Committed by Catalin Marinas
Browse files

arm64: cpufeature: add feature for CRC32 instructions 



Add a CRC32 feature bit and wire it up to the CPU id register so we
will be able to use alternatives patching for CRC32 operations.

Acked-by: default avatarWill Deacon <will.deacon@arm.com>
Signed-off-by: default avatarArd Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: default avatarCatalin Marinas <catalin.marinas@arm.com>
parent 9784d82d

arch/arm64/include/asm/cpucaps.h

+2 −1
Original line number Diff line number Diff line
@@ -51,7 +51,8 @@ 
#define ARM64_SSBD				30

#define ARM64_MISMATCHED_CACHE_TYPE		31

#define ARM64_HAS_STAGE2_FWB			32

#define ARM64_HAS_CRC32				33



#define ARM64_NCAPS				33

#define ARM64_NCAPS				34



#endif /* __ASM_CPUCAPS_H */

arch/arm64/kernel/cpufeature.c

+9 −0
Original line number Diff line number Diff line
@@ -1222,6 +1222,15 @@ static const struct arm64_cpu_capabilities arm64_features[] = { 
		.cpu_enable = cpu_enable_hw_dbm,

	},

#endif

	{

		.desc = "CRC32 instructions",

		.capability = ARM64_HAS_CRC32,

		.type = ARM64_CPUCAP_SYSTEM_FEATURE,

		.matches = has_cpuid_feature,

		.sys_reg = SYS_ID_AA64ISAR0_EL1,

		.field_pos = ID_AA64ISAR0_CRC32_SHIFT,

		.min_field_value = 1,

	},

	{},

};

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