[PATCH v4 14/17] arm64: Add a capability for FEAT_ECV

From: Marc Zyngier
Date: Sun Oct 17 2021 - 08:46:54 EST


Add a new capability to detect the Enhanced Counter Virtualization
feature (FEAT_ECV).

Reviewed-by: Oliver Upton <oupton@xxxxxxxxxx>
Acked-by: Will Deacon <will@xxxxxxxxxx>
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
---
arch/arm64/kernel/cpufeature.c | 10 ++++++++++
arch/arm64/tools/cpucaps | 1 +
2 files changed, 11 insertions(+)

diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index f8a3067d10c6..26b11ce8fff6 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -1926,6 +1926,16 @@ static const struct arm64_cpu_capabilities arm64_features[] = {
.sign = FTR_UNSIGNED,
.min_field_value = 1,
},
+ {
+ .desc = "Enhanced Counter Virtualization",
+ .capability = ARM64_HAS_ECV,
+ .type = ARM64_CPUCAP_SYSTEM_FEATURE,
+ .matches = has_cpuid_feature,
+ .sys_reg = SYS_ID_AA64MMFR0_EL1,
+ .field_pos = ID_AA64MMFR0_ECV_SHIFT,
+ .sign = FTR_UNSIGNED,
+ .min_field_value = 1,
+ },
#ifdef CONFIG_ARM64_PAN
{
.desc = "Privileged Access Never",
diff --git a/arch/arm64/tools/cpucaps b/arch/arm64/tools/cpucaps
index 49305c2e6dfd..7a7c58acd8f0 100644
--- a/arch/arm64/tools/cpucaps
+++ b/arch/arm64/tools/cpucaps
@@ -18,6 +18,7 @@ HAS_CRC32
HAS_DCPODP
HAS_DCPOP
HAS_E0PD
+HAS_ECV
HAS_EPAN
HAS_GENERIC_AUTH
HAS_GENERIC_AUTH_ARCH
--
2.30.2