Commit bf49e73d authored by Oliver Upton's avatar Oliver Upton
Browse files

arm64: Detect FEAT_SCTLR2 



KVM is about to pick up support for SCTLR2. Add cpucap for later use in
the guest/host context switch hot path.

Reviewed-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20250708172532.1699409-2-oliver.upton@linux.dev


Signed-off-by: default avatarOliver Upton <oliver.upton@linux.dev>
parent 86731a2a

arch/arm64/kernel/cpufeature.c

+8 −0
Original line number Diff line number Diff line
@@ -500,6 +500,7 @@ static const struct arm64_ftr_bits ftr_id_aa64mmfr3[] = { 
	ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_POE),

		       FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR3_EL1_S1POE_SHIFT, 4, 0),

	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR3_EL1_S1PIE_SHIFT, 4, 0),

	ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_AA64MMFR3_EL1_SCTLRX_SHIFT, 4, 0),

	ARM64_FTR_BITS(FTR_HIDDEN, FTR_NONSTRICT, FTR_LOWER_SAFE, ID_AA64MMFR3_EL1_TCRX_SHIFT, 4, 0),

	ARM64_FTR_END,

};
@@ -3061,6 +3062,13 @@ static const struct arm64_cpu_capabilities arm64_features[] = { 
		.matches = has_pmuv3,

	},

#endif

	{

		.desc = "SCTLR2",

		.capability = ARM64_HAS_SCTLR2,

		.type = ARM64_CPUCAP_SYSTEM_FEATURE,

		.matches = has_cpuid_feature,

		ARM64_CPUID_FIELDS(ID_AA64MMFR3_EL1, SCTLRX, IMP)

	},

	{},

};

arch/arm64/tools/cpucaps

+1 −0
Original line number Diff line number Diff line
@@ -49,6 +49,7 @@ HAS_PAN 
HAS_PMUV3

HAS_S1PIE

HAS_S1POE

HAS_SCTLR2

HAS_RAS_EXTN

HAS_RNG

HAS_SB