diff options
| author | Marc Zyngier <maz@kernel.org> | 2022-11-13 19:38:26 +0300 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2022-11-19 15:56:39 +0300 |
| commit | 3d0dba5764b94308b8c4257ad64e383f11ce0c92 (patch) | |
| tree | e8222c5ada162482953e8094ff9408008b9e60e7 /arch/arm64/kvm/sys_regs.c | |
| parent | 26d2d0594d7016dbcbce4038aa202c2858d5a944 (diff) | |
| download | linux-3d0dba5764b94308b8c4257ad64e383f11ce0c92.tar.xz | |
KVM: arm64: PMU: Move the ID_AA64DFR0_EL1.PMUver limit to VM creation
As further patches will enable the selection of a PMU revision
from userspace, sample the supported PMU revision at VM creation
time, rather than building each time the ID_AA64DFR0_EL1 register
is accessed.
This shouldn't result in any change in behaviour.
Reviewed-by: Reiji Watanabe <reijiw@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20221113163832.3154370-11-maz@kernel.org
Diffstat (limited to 'arch/arm64/kvm/sys_regs.c')
| -rw-r--r-- | arch/arm64/kvm/sys_regs.c | 36 |
1 files changed, 28 insertions, 8 deletions
diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index f4a7c5abcbca..297b4fcbf969 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -1062,6 +1062,27 @@ static bool access_arch_timer(struct kvm_vcpu *vcpu, return true; } +static u8 vcpu_pmuver(const struct kvm_vcpu *vcpu) +{ + if (kvm_vcpu_has_pmu(vcpu)) + return vcpu->kvm->arch.dfr0_pmuver.imp; + + return vcpu->kvm->arch.dfr0_pmuver.unimp; +} + +static u8 pmuver_to_perfmon(u8 pmuver) +{ + switch (pmuver) { + case ID_AA64DFR0_EL1_PMUVer_IMP: + return ID_DFR0_PERFMON_8_0; + case ID_AA64DFR0_EL1_PMUVer_IMP_DEF: + return ID_DFR0_PERFMON_IMP_DEF; + default: + /* Anything ARMv8.1+ and NI have the same value. For now. */ + return pmuver; + } +} + /* Read a sanitised cpufeature ID register by sys_reg_desc */ static u64 read_id_reg(const struct kvm_vcpu *vcpu, struct sys_reg_desc const *r) { @@ -1111,18 +1132,17 @@ static u64 read_id_reg(const struct kvm_vcpu *vcpu, struct sys_reg_desc const *r /* Limit debug to ARMv8.0 */ val &= ~ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_DebugVer); val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_DebugVer), 6); - /* Limit guests to PMUv3 for ARMv8.4 */ - val = cpuid_feature_cap_perfmon_field(val, - ID_AA64DFR0_EL1_PMUVer_SHIFT, - kvm_vcpu_has_pmu(vcpu) ? ID_AA64DFR0_EL1_PMUVer_V3P4 : 0); + /* Set PMUver to the required version */ + val &= ~ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer); + val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMUVer), + vcpu_pmuver(vcpu)); /* Hide SPE from guests */ val &= ~ARM64_FEATURE_MASK(ID_AA64DFR0_EL1_PMSVer); break; case SYS_ID_DFR0_EL1: - /* Limit guests to PMUv3 for ARMv8.4 */ - val = cpuid_feature_cap_perfmon_field(val, - ID_DFR0_PERFMON_SHIFT, - kvm_vcpu_has_pmu(vcpu) ? ID_DFR0_PERFMON_8_4 : 0); + val &= ~ARM64_FEATURE_MASK(ID_DFR0_PERFMON); + val |= FIELD_PREP(ARM64_FEATURE_MASK(ID_DFR0_PERFMON), + pmuver_to_perfmon(vcpu_pmuver(vcpu))); break; } |