Commit 32634994 authored by Marc Zyngier's avatar Marc Zyngier
Browse files

arm64: Add HAS_ECV_CNTPOFF capability 



Add the probing code for the FEAT_ECV variant that implements CNTPOFF_EL2.
Why it is optional is a mystery, but let's try and detect it.

Reviewed-by: default avatarReiji Watanabe <reijiw@google.com>
Reviewed-by: default avatarColton Lewis <coltonlewis@google.com>
Signed-off-by: default avatarMarc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20230330174800.2677007-4-maz@kernel.org
parent eaacaa4f

arch/arm64/kernel/cpufeature.c

+11 −0
Original line number Diff line number Diff line
@@ -2223,6 +2223,17 @@ static const struct arm64_cpu_capabilities arm64_features[] = { 
		.sign = FTR_UNSIGNED,

		.min_field_value = 1,

	},

	{

		.desc = "Enhanced Counter Virtualization (CNTPOFF)",

		.capability = ARM64_HAS_ECV_CNTPOFF,

		.type = ARM64_CPUCAP_SYSTEM_FEATURE,

		.matches = has_cpuid_feature,

		.sys_reg = SYS_ID_AA64MMFR0_EL1,

		.field_pos = ID_AA64MMFR0_EL1_ECV_SHIFT,

		.field_width = 4,

		.sign = FTR_UNSIGNED,

		.min_field_value = ID_AA64MMFR0_EL1_ECV_CNTPOFF,

	},

#ifdef CONFIG_ARM64_PAN

	{

		.desc = "Privileged Access Never",

arch/arm64/tools/cpucaps

+1 −0
Original line number Diff line number Diff line
@@ -23,6 +23,7 @@ HAS_DCPOP 
HAS_DIT

HAS_E0PD

HAS_ECV

HAS_ECV_CNTPOFF

HAS_EPAN

HAS_GENERIC_AUTH

HAS_GENERIC_AUTH_ARCH_QARMA3