arm64: KVM: Add helper to handle PMCR register bits
According to ARMv8 spec, when writing 1 to PMCR.E, all counters are
enabled by PMCNTENSET, while writing 0 to PMCR.E, all counters are
disabled. When writing 1 to PMCR.P, reset all event counters, not
including PMCCNTR, to zero. When writing 1 to PMCR.C, reset PMCCNTR to
zero.
Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
diff --git a/virt/kvm/arm/pmu.c b/virt/kvm/arm/pmu.c
index 9fc775e..cda869c 100644
--- a/virt/kvm/arm/pmu.c
+++ b/virt/kvm/arm/pmu.c
@@ -210,6 +210,40 @@
}
}
+/**
+ * kvm_pmu_handle_pmcr - handle PMCR register
+ * @vcpu: The vcpu pointer
+ * @val: the value guest writes to PMCR register
+ */
+void kvm_pmu_handle_pmcr(struct kvm_vcpu *vcpu, u64 val)
+{
+ struct kvm_pmu *pmu = &vcpu->arch.pmu;
+ struct kvm_pmc *pmc;
+ u64 mask;
+ int i;
+
+ mask = kvm_pmu_valid_counter_mask(vcpu);
+ if (val & ARMV8_PMU_PMCR_E) {
+ kvm_pmu_enable_counter(vcpu,
+ vcpu_sys_reg(vcpu, PMCNTENSET_EL0) & mask);
+ } else {
+ kvm_pmu_disable_counter(vcpu, mask);
+ }
+
+ if (val & ARMV8_PMU_PMCR_C)
+ kvm_pmu_set_counter_value(vcpu, ARMV8_PMU_CYCLE_IDX, 0);
+
+ if (val & ARMV8_PMU_PMCR_P) {
+ for (i = 0; i < ARMV8_PMU_CYCLE_IDX; i++)
+ kvm_pmu_set_counter_value(vcpu, i, 0);
+ }
+
+ if (val & ARMV8_PMU_PMCR_LC) {
+ pmc = &pmu->pmc[ARMV8_PMU_CYCLE_IDX];
+ pmc->bitmask = 0xffffffffffffffffUL;
+ }
+}
+
static bool kvm_pmu_counter_is_enabled(struct kvm_vcpu *vcpu, u64 select_idx)
{
return (vcpu_sys_reg(vcpu, PMCR_EL0) & ARMV8_PMU_PMCR_E) &&