| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * KVM PMU support for AMD |
| * |
| * Copyright 2015, Red Hat, Inc. and/or its affiliates. |
| * |
| * Author: |
| * Wei Huang <wei@redhat.com> |
| * |
| * Implementation is based on pmu_intel.c file |
| */ |
| #include <linux/types.h> |
| #include <linux/kvm_host.h> |
| #include <linux/perf_event.h> |
| #include "x86.h" |
| #include "cpuid.h" |
| #include "lapic.h" |
| #include "pmu.h" |
| |
| enum pmu_type { |
| PMU_TYPE_COUNTER = 0, |
| PMU_TYPE_EVNTSEL, |
| }; |
| |
| enum index { |
| INDEX_ZERO = 0, |
| INDEX_ONE, |
| INDEX_TWO, |
| INDEX_THREE, |
| INDEX_FOUR, |
| INDEX_FIVE, |
| INDEX_ERROR, |
| }; |
| |
| /* duplicated from amd_perfmon_event_map, K7 and above should work. */ |
| static struct kvm_event_hw_type_mapping amd_event_mapping[] = { |
| [0] = { 0x76, 0x00, PERF_COUNT_HW_CPU_CYCLES }, |
| [1] = { 0xc0, 0x00, PERF_COUNT_HW_INSTRUCTIONS }, |
| [2] = { 0x7d, 0x07, PERF_COUNT_HW_CACHE_REFERENCES }, |
| [3] = { 0x7e, 0x07, PERF_COUNT_HW_CACHE_MISSES }, |
| [4] = { 0xc2, 0x00, PERF_COUNT_HW_BRANCH_INSTRUCTIONS }, |
| [5] = { 0xc3, 0x00, PERF_COUNT_HW_BRANCH_MISSES }, |
| [6] = { 0xd0, 0x00, PERF_COUNT_HW_STALLED_CYCLES_FRONTEND }, |
| [7] = { 0xd1, 0x00, PERF_COUNT_HW_STALLED_CYCLES_BACKEND }, |
| }; |
| |
| static unsigned int get_msr_base(struct kvm_pmu *pmu, enum pmu_type type) |
| { |
| struct kvm_vcpu *vcpu = pmu_to_vcpu(pmu); |
| |
| if (guest_cpuid_has(vcpu, X86_FEATURE_PERFCTR_CORE)) { |
| if (type == PMU_TYPE_COUNTER) |
| return MSR_F15H_PERF_CTR; |
| else |
| return MSR_F15H_PERF_CTL; |
| } else { |
| if (type == PMU_TYPE_COUNTER) |
| return MSR_K7_PERFCTR0; |
| else |
| return MSR_K7_EVNTSEL0; |
| } |
| } |
| |
| static enum index msr_to_index(u32 msr) |
| { |
| switch (msr) { |
| case MSR_F15H_PERF_CTL0: |
| case MSR_F15H_PERF_CTR0: |
| case MSR_K7_EVNTSEL0: |
| case MSR_K7_PERFCTR0: |
| return INDEX_ZERO; |
| case MSR_F15H_PERF_CTL1: |
| case MSR_F15H_PERF_CTR1: |
| case MSR_K7_EVNTSEL1: |
| case MSR_K7_PERFCTR1: |
| return INDEX_ONE; |
| case MSR_F15H_PERF_CTL2: |
| case MSR_F15H_PERF_CTR2: |
| case MSR_K7_EVNTSEL2: |
| case MSR_K7_PERFCTR2: |
| return INDEX_TWO; |
| case MSR_F15H_PERF_CTL3: |
| case MSR_F15H_PERF_CTR3: |
| case MSR_K7_EVNTSEL3: |
| case MSR_K7_PERFCTR3: |
| return INDEX_THREE; |
| case MSR_F15H_PERF_CTL4: |
| case MSR_F15H_PERF_CTR4: |
| return INDEX_FOUR; |
| case MSR_F15H_PERF_CTL5: |
| case MSR_F15H_PERF_CTR5: |
| return INDEX_FIVE; |
| default: |
| return INDEX_ERROR; |
| } |
| } |
| |
| static inline struct kvm_pmc *get_gp_pmc_amd(struct kvm_pmu *pmu, u32 msr, |
| enum pmu_type type) |
| { |
| switch (msr) { |
| case MSR_F15H_PERF_CTL0: |
| case MSR_F15H_PERF_CTL1: |
| case MSR_F15H_PERF_CTL2: |
| case MSR_F15H_PERF_CTL3: |
| case MSR_F15H_PERF_CTL4: |
| case MSR_F15H_PERF_CTL5: |
| case MSR_K7_EVNTSEL0 ... MSR_K7_EVNTSEL3: |
| if (type != PMU_TYPE_EVNTSEL) |
| return NULL; |
| break; |
| case MSR_F15H_PERF_CTR0: |
| case MSR_F15H_PERF_CTR1: |
| case MSR_F15H_PERF_CTR2: |
| case MSR_F15H_PERF_CTR3: |
| case MSR_F15H_PERF_CTR4: |
| case MSR_F15H_PERF_CTR5: |
| case MSR_K7_PERFCTR0 ... MSR_K7_PERFCTR3: |
| if (type != PMU_TYPE_COUNTER) |
| return NULL; |
| break; |
| default: |
| return NULL; |
| } |
| |
| return &pmu->gp_counters[msr_to_index(msr)]; |
| } |
| |
| static unsigned amd_find_arch_event(struct kvm_pmu *pmu, |
| u8 event_select, |
| u8 unit_mask) |
| { |
| int i; |
| |
| for (i = 0; i < ARRAY_SIZE(amd_event_mapping); i++) |
| if (amd_event_mapping[i].eventsel == event_select |
| && amd_event_mapping[i].unit_mask == unit_mask) |
| break; |
| |
| if (i == ARRAY_SIZE(amd_event_mapping)) |
| return PERF_COUNT_HW_MAX; |
| |
| return amd_event_mapping[i].event_type; |
| } |
| |
| /* return PERF_COUNT_HW_MAX as AMD doesn't have fixed events */ |
| static unsigned amd_find_fixed_event(int idx) |
| { |
| return PERF_COUNT_HW_MAX; |
| } |
| |
| /* check if a PMC is enabled by comparing it against global_ctrl bits. Because |
| * AMD CPU doesn't have global_ctrl MSR, all PMCs are enabled (return TRUE). |
| */ |
| static bool amd_pmc_is_enabled(struct kvm_pmc *pmc) |
| { |
| return true; |
| } |
| |
| static struct kvm_pmc *amd_pmc_idx_to_pmc(struct kvm_pmu *pmu, int pmc_idx) |
| { |
| unsigned int base = get_msr_base(pmu, PMU_TYPE_COUNTER); |
| struct kvm_vcpu *vcpu = pmu_to_vcpu(pmu); |
| |
| if (guest_cpuid_has(vcpu, X86_FEATURE_PERFCTR_CORE)) { |
| /* |
| * The idx is contiguous. The MSRs are not. The counter MSRs |
| * are interleaved with the event select MSRs. |
| */ |
| pmc_idx *= 2; |
| } |
| |
| return get_gp_pmc_amd(pmu, base + pmc_idx, PMU_TYPE_COUNTER); |
| } |
| |
| /* returns 0 if idx's corresponding MSR exists; otherwise returns 1. */ |
| static int amd_is_valid_msr_idx(struct kvm_vcpu *vcpu, unsigned idx) |
| { |
| struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); |
| |
| idx &= ~(3u << 30); |
| |
| return (idx >= pmu->nr_arch_gp_counters); |
| } |
| |
| /* idx is the ECX register of RDPMC instruction */ |
| static struct kvm_pmc *amd_msr_idx_to_pmc(struct kvm_vcpu *vcpu, unsigned idx, u64 *mask) |
| { |
| struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); |
| struct kvm_pmc *counters; |
| |
| idx &= ~(3u << 30); |
| if (idx >= pmu->nr_arch_gp_counters) |
| return NULL; |
| counters = pmu->gp_counters; |
| |
| return &counters[idx]; |
| } |
| |
| static bool amd_is_valid_msr(struct kvm_vcpu *vcpu, u32 msr) |
| { |
| struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); |
| int ret = false; |
| |
| ret = get_gp_pmc_amd(pmu, msr, PMU_TYPE_COUNTER) || |
| get_gp_pmc_amd(pmu, msr, PMU_TYPE_EVNTSEL); |
| |
| return ret; |
| } |
| |
| static int amd_pmu_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *data) |
| { |
| struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); |
| struct kvm_pmc *pmc; |
| |
| /* MSR_PERFCTRn */ |
| pmc = get_gp_pmc_amd(pmu, msr, PMU_TYPE_COUNTER); |
| if (pmc) { |
| *data = pmc_read_counter(pmc); |
| return 0; |
| } |
| /* MSR_EVNTSELn */ |
| pmc = get_gp_pmc_amd(pmu, msr, PMU_TYPE_EVNTSEL); |
| if (pmc) { |
| *data = pmc->eventsel; |
| return 0; |
| } |
| |
| return 1; |
| } |
| |
| static int amd_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) |
| { |
| struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); |
| struct kvm_pmc *pmc; |
| u32 msr = msr_info->index; |
| u64 data = msr_info->data; |
| |
| /* MSR_PERFCTRn */ |
| pmc = get_gp_pmc_amd(pmu, msr, PMU_TYPE_COUNTER); |
| if (pmc) { |
| pmc->counter += data - pmc_read_counter(pmc); |
| return 0; |
| } |
| /* MSR_EVNTSELn */ |
| pmc = get_gp_pmc_amd(pmu, msr, PMU_TYPE_EVNTSEL); |
| if (pmc) { |
| if (data == pmc->eventsel) |
| return 0; |
| if (!(data & pmu->reserved_bits)) { |
| reprogram_gp_counter(pmc, data); |
| return 0; |
| } |
| } |
| |
| return 1; |
| } |
| |
| static void amd_pmu_refresh(struct kvm_vcpu *vcpu) |
| { |
| struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); |
| |
| if (guest_cpuid_has(vcpu, X86_FEATURE_PERFCTR_CORE)) |
| pmu->nr_arch_gp_counters = AMD64_NUM_COUNTERS_CORE; |
| else |
| pmu->nr_arch_gp_counters = AMD64_NUM_COUNTERS; |
| |
| pmu->counter_bitmask[KVM_PMC_GP] = ((u64)1 << 48) - 1; |
| pmu->reserved_bits = 0xffffffff00200000ull; |
| pmu->version = 1; |
| /* not applicable to AMD; but clean them to prevent any fall out */ |
| pmu->counter_bitmask[KVM_PMC_FIXED] = 0; |
| pmu->nr_arch_fixed_counters = 0; |
| pmu->global_status = 0; |
| } |
| |
| static void amd_pmu_init(struct kvm_vcpu *vcpu) |
| { |
| struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); |
| int i; |
| |
| BUILD_BUG_ON(AMD64_NUM_COUNTERS_CORE > INTEL_PMC_MAX_GENERIC); |
| |
| for (i = 0; i < AMD64_NUM_COUNTERS_CORE ; i++) { |
| pmu->gp_counters[i].type = KVM_PMC_GP; |
| pmu->gp_counters[i].vcpu = vcpu; |
| pmu->gp_counters[i].idx = i; |
| } |
| } |
| |
| static void amd_pmu_reset(struct kvm_vcpu *vcpu) |
| { |
| struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); |
| int i; |
| |
| for (i = 0; i < AMD64_NUM_COUNTERS_CORE; i++) { |
| struct kvm_pmc *pmc = &pmu->gp_counters[i]; |
| |
| pmc_stop_counter(pmc); |
| pmc->counter = pmc->eventsel = 0; |
| } |
| } |
| |
| struct kvm_pmu_ops amd_pmu_ops = { |
| .find_arch_event = amd_find_arch_event, |
| .find_fixed_event = amd_find_fixed_event, |
| .pmc_is_enabled = amd_pmc_is_enabled, |
| .pmc_idx_to_pmc = amd_pmc_idx_to_pmc, |
| .msr_idx_to_pmc = amd_msr_idx_to_pmc, |
| .is_valid_msr_idx = amd_is_valid_msr_idx, |
| .is_valid_msr = amd_is_valid_msr, |
| .get_msr = amd_pmu_get_msr, |
| .set_msr = amd_pmu_set_msr, |
| .refresh = amd_pmu_refresh, |
| .init = amd_pmu_init, |
| .reset = amd_pmu_reset, |
| }; |