Upgrading the PMU code from ARMv8.1 to ARMv8.4 turns out to be pretty easy. All that is required is support for PMMIR_EL1, which is read-only, and for which returning 0 is a valid option as long as we don't advertise STALL_SLOT as an implemented event. Let's just do that and adjust what we return to the guest. Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx> --- arch/arm64/include/asm/sysreg.h | 3 +++ arch/arm64/kvm/pmu-emul.c | 6 ++++++ arch/arm64/kvm/sys_regs.c | 11 +++++++---- 3 files changed, 16 insertions(+), 4 deletions(-) diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h index 8b5e7e5c3cc8..2fb3f386588c 100644 --- a/arch/arm64/include/asm/sysreg.h +++ b/arch/arm64/include/asm/sysreg.h @@ -846,7 +846,10 @@ #define ID_DFR0_PERFMON_SHIFT 24 +#define ID_DFR0_PERFMON_8_0 0x3 #define ID_DFR0_PERFMON_8_1 0x4 +#define ID_DFR0_PERFMON_8_4 0x5 +#define ID_DFR0_PERFMON_8_5 0x6 #define ID_ISAR4_SWP_FRAC_SHIFT 28 #define ID_ISAR4_PSR_M_SHIFT 24 diff --git a/arch/arm64/kvm/pmu-emul.c b/arch/arm64/kvm/pmu-emul.c index 398f6df1bbe4..72cd704a8368 100644 --- a/arch/arm64/kvm/pmu-emul.c +++ b/arch/arm64/kvm/pmu-emul.c @@ -795,6 +795,12 @@ u64 kvm_pmu_get_pmceid(struct kvm_vcpu *vcpu, bool pmceid1) base = 0; } else { val = read_sysreg(pmceid1_el0); + /* + * Don't advertise STALL_SLOT, as PMMIR_EL0 is handled + * as RAZ + */ + if (vcpu->kvm->arch.pmuver >= ID_AA64DFR0_PMUVER_8_4) + val &= ~BIT_ULL(ARMV8_PMUV3_PERFCTR_STALL_SLOT - 32); base = 32; } diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 8f79ec1fffa7..5da536ab738d 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -1051,16 +1051,16 @@ static u64 read_id_reg(const struct kvm_vcpu *vcpu, /* Limit debug to ARMv8.0 */ val &= ~FEATURE(ID_AA64DFR0_DEBUGVER); val |= FIELD_PREP(FEATURE(ID_AA64DFR0_DEBUGVER), 6); - /* Limit guests to PMUv3 for ARMv8.1 */ + /* Limit guests to PMUv3 for ARMv8.4 */ val = cpuid_feature_cap_perfmon_field(val, ID_AA64DFR0_PMUVER_SHIFT, - kvm_vcpu_has_pmu(vcpu) ? ID_AA64DFR0_PMUVER_8_1 : 0); + kvm_vcpu_has_pmu(vcpu) ? ID_AA64DFR0_PMUVER_8_4 : 0); break; case SYS_ID_DFR0_EL1: - /* Limit guests to PMUv3 for ARMv8.1 */ + /* 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_1 : 0); + kvm_vcpu_has_pmu(vcpu) ? ID_DFR0_PERFMON_8_4 : 0); break; } @@ -1496,6 +1496,7 @@ static const struct sys_reg_desc sys_reg_descs[] = { { SYS_DESC(SYS_PMINTENSET_EL1), access_pminten, reset_unknown, PMINTENSET_EL1 }, { SYS_DESC(SYS_PMINTENCLR_EL1), access_pminten, reset_unknown, PMINTENSET_EL1 }, + { SYS_DESC(SYS_PMMIR_EL1), trap_raz_wi }, { SYS_DESC(SYS_MAIR_EL1), access_vm_reg, reset_unknown, MAIR_EL1 }, { SYS_DESC(SYS_AMAIR_EL1), access_vm_reg, reset_amair_el1, AMAIR_EL1 }, @@ -1918,6 +1919,8 @@ static const struct sys_reg_desc cp15_regs[] = { { Op1( 0), CRn( 9), CRm(14), Op2( 3), access_pmovs }, { AA32(HI), Op1( 0), CRn( 9), CRm(14), Op2( 4), access_pmceid }, { AA32(HI), Op1( 0), CRn( 9), CRm(14), Op2( 5), access_pmceid }, + /* PMMIR */ + { Op1( 0), CRn( 9), CRm(14), Op2( 6), trap_raz_wi }, /* PRRR/MAIR0 */ { AA32(LO), Op1( 0), CRn(10), CRm( 2), Op2( 0), access_vm_reg, NULL, MAIR_EL1 }, -- 2.29.2