diff options
| author | Sascha Bischoff <Sascha.Bischoff@arm.com> | 2025-08-28 10:59:42 +0000 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2025-09-17 17:41:02 +0100 |
| commit | 7847f51189343b29a24ca7edafb60a9032d5acf8 (patch) | |
| tree | 9e4ed1ba84f4265b021c8d2d0c080f10529a88b2 | |
| parent | d5a012af348d4d84287267547eb8637b937545af (diff) | |
arm64: cpucaps: Add GICv5 Legacy vCPU interface (GCIE_LEGACY) capability
Implement the GCIE_LEGACY capability as a system feature to be able to
check for support from KVM. The type is explicitly
ARM64_CPUCAP_EARLY_LOCAL_CPU_FEATURE, which means that the capability
is enabled early if all boot CPUs support it. Additionally, if this
capability is enabled during boot, it prevents late onlining of CPUs
that lack it, thereby avoiding potential mismatched configurations
which would break KVM.
Signed-off-by: Sascha Bischoff <sascha.bischoff@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Signed-off-by: Marc Zyngier <maz@kernel.org>
| -rw-r--r-- | arch/arm64/kernel/cpufeature.c | 15 | ||||
| -rw-r--r-- | arch/arm64/tools/cpucaps | 1 |
2 files changed, 16 insertions, 0 deletions
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index ef269a5a37e1..770a41fa7214 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -2539,6 +2539,15 @@ test_has_mpam_hcr(const struct arm64_cpu_capabilities *entry, int scope) return idr & MPAMIDR_EL1_HAS_HCR; } +static bool +test_has_gicv5_legacy(const struct arm64_cpu_capabilities *entry, int scope) +{ + if (!this_cpu_has_cap(ARM64_HAS_GICV5_CPUIF)) + return false; + + return !!(read_sysreg_s(SYS_ICC_IDR0_EL1) & ICC_IDR0_EL1_GCIE_LEGACY); +} + static const struct arm64_cpu_capabilities arm64_features[] = { { .capability = ARM64_ALWAYS_BOOT, @@ -3156,6 +3165,12 @@ static const struct arm64_cpu_capabilities arm64_features[] = { .matches = has_cpuid_feature, ARM64_CPUID_FIELDS(ID_AA64PFR2_EL1, GCIE, IMP) }, + { + .desc = "GICv5 Legacy vCPU interface", + .type = ARM64_CPUCAP_EARLY_LOCAL_CPU_FEATURE, + .capability = ARM64_HAS_GICV5_LEGACY, + .matches = test_has_gicv5_legacy, + }, {}, }; diff --git a/arch/arm64/tools/cpucaps b/arch/arm64/tools/cpucaps index 9ff5cdbd2759..1b32c1232d28 100644 --- a/arch/arm64/tools/cpucaps +++ b/arch/arm64/tools/cpucaps @@ -37,6 +37,7 @@ HAS_GENERIC_AUTH_ARCH_QARMA5 HAS_GENERIC_AUTH_IMP_DEF HAS_GICV3_CPUIF HAS_GICV5_CPUIF +HAS_GICV5_LEGACY HAS_GIC_PRIO_MASKING HAS_GIC_PRIO_RELAXED_SYNC HAS_HCR_NV1 |