1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * KVM PMU support for AMD 4 * 5 * Copyright 2015, Red Hat, Inc. and/or its affiliates. 6 * 7 * Author: 8 * Wei Huang <wei@redhat.com> 9 * 10 * Implementation is based on pmu_intel.c file 11 */ 12 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 13 14 #include <linux/types.h> 15 #include <linux/kvm_host.h> 16 #include <linux/perf_event.h> 17 #include "x86.h" 18 #include "cpuid.h" 19 #include "lapic.h" 20 #include "pmu.h" 21 #include "svm.h" 22 23 enum pmu_type { 24 PMU_TYPE_COUNTER = 0, 25 PMU_TYPE_EVNTSEL, 26 }; 27 28 static struct kvm_pmc *amd_pmc_idx_to_pmc(struct kvm_pmu *pmu, int pmc_idx) 29 { 30 unsigned int num_counters = pmu->nr_arch_gp_counters; 31 32 if (pmc_idx >= num_counters) 33 return NULL; 34 35 return &pmu->gp_counters[array_index_nospec(pmc_idx, num_counters)]; 36 } 37 38 static inline struct kvm_pmc *get_gp_pmc_amd(struct kvm_pmu *pmu, u32 msr, 39 enum pmu_type type) 40 { 41 struct kvm_vcpu *vcpu = pmu_to_vcpu(pmu); 42 unsigned int idx; 43 44 if (!vcpu->kvm->arch.enable_pmu) 45 return NULL; 46 47 switch (msr) { 48 case MSR_F15H_PERF_CTL0 ... MSR_F15H_PERF_CTR5: 49 if (!guest_cpuid_has(vcpu, X86_FEATURE_PERFCTR_CORE)) 50 return NULL; 51 /* 52 * Each PMU counter has a pair of CTL and CTR MSRs. CTLn 53 * MSRs (accessed via EVNTSEL) are even, CTRn MSRs are odd. 54 */ 55 idx = (unsigned int)((msr - MSR_F15H_PERF_CTL0) / 2); 56 if (!(msr & 0x1) != (type == PMU_TYPE_EVNTSEL)) 57 return NULL; 58 break; 59 case MSR_K7_EVNTSEL0 ... MSR_K7_EVNTSEL3: 60 if (type != PMU_TYPE_EVNTSEL) 61 return NULL; 62 idx = msr - MSR_K7_EVNTSEL0; 63 break; 64 case MSR_K7_PERFCTR0 ... MSR_K7_PERFCTR3: 65 if (type != PMU_TYPE_COUNTER) 66 return NULL; 67 idx = msr - MSR_K7_PERFCTR0; 68 break; 69 default: 70 return NULL; 71 } 72 73 return amd_pmc_idx_to_pmc(pmu, idx); 74 } 75 76 static bool amd_hw_event_available(struct kvm_pmc *pmc) 77 { 78 return true; 79 } 80 81 static bool amd_is_valid_rdpmc_ecx(struct kvm_vcpu *vcpu, unsigned int idx) 82 { 83 struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); 84 85 idx &= ~(3u << 30); 86 87 return idx < pmu->nr_arch_gp_counters; 88 } 89 90 /* idx is the ECX register of RDPMC instruction */ 91 static struct kvm_pmc *amd_rdpmc_ecx_to_pmc(struct kvm_vcpu *vcpu, 92 unsigned int idx, u64 *mask) 93 { 94 return amd_pmc_idx_to_pmc(vcpu_to_pmu(vcpu), idx & ~(3u << 30)); 95 } 96 97 static struct kvm_pmc *amd_msr_idx_to_pmc(struct kvm_vcpu *vcpu, u32 msr) 98 { 99 struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); 100 struct kvm_pmc *pmc; 101 102 pmc = get_gp_pmc_amd(pmu, msr, PMU_TYPE_COUNTER); 103 pmc = pmc ? pmc : get_gp_pmc_amd(pmu, msr, PMU_TYPE_EVNTSEL); 104 105 return pmc; 106 } 107 108 static bool amd_is_valid_msr(struct kvm_vcpu *vcpu, u32 msr) 109 { 110 struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); 111 112 switch (msr) { 113 case MSR_K7_EVNTSEL0 ... MSR_K7_PERFCTR3: 114 return pmu->version > 0; 115 case MSR_F15H_PERF_CTL0 ... MSR_F15H_PERF_CTR5: 116 return guest_cpuid_has(vcpu, X86_FEATURE_PERFCTR_CORE); 117 case MSR_AMD64_PERF_CNTR_GLOBAL_STATUS: 118 case MSR_AMD64_PERF_CNTR_GLOBAL_CTL: 119 case MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_CLR: 120 return pmu->version > 1; 121 default: 122 if (msr > MSR_F15H_PERF_CTR5 && 123 msr < MSR_F15H_PERF_CTL0 + 2 * pmu->nr_arch_gp_counters) 124 return pmu->version > 1; 125 break; 126 } 127 128 return amd_msr_idx_to_pmc(vcpu, msr); 129 } 130 131 static int amd_pmu_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) 132 { 133 struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); 134 struct kvm_pmc *pmc; 135 u32 msr = msr_info->index; 136 137 /* MSR_PERFCTRn */ 138 pmc = get_gp_pmc_amd(pmu, msr, PMU_TYPE_COUNTER); 139 if (pmc) { 140 msr_info->data = pmc_read_counter(pmc); 141 return 0; 142 } 143 /* MSR_EVNTSELn */ 144 pmc = get_gp_pmc_amd(pmu, msr, PMU_TYPE_EVNTSEL); 145 if (pmc) { 146 msr_info->data = pmc->eventsel; 147 return 0; 148 } 149 150 return 1; 151 } 152 153 static int amd_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) 154 { 155 struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); 156 struct kvm_pmc *pmc; 157 u32 msr = msr_info->index; 158 u64 data = msr_info->data; 159 160 /* MSR_PERFCTRn */ 161 pmc = get_gp_pmc_amd(pmu, msr, PMU_TYPE_COUNTER); 162 if (pmc) { 163 pmc_write_counter(pmc, data); 164 pmc_update_sample_period(pmc); 165 return 0; 166 } 167 /* MSR_EVNTSELn */ 168 pmc = get_gp_pmc_amd(pmu, msr, PMU_TYPE_EVNTSEL); 169 if (pmc) { 170 data &= ~pmu->reserved_bits; 171 if (data != pmc->eventsel) { 172 pmc->eventsel = data; 173 kvm_pmu_request_counter_reprogram(pmc); 174 } 175 return 0; 176 } 177 178 return 1; 179 } 180 181 static void amd_pmu_refresh(struct kvm_vcpu *vcpu) 182 { 183 struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); 184 union cpuid_0x80000022_ebx ebx; 185 186 pmu->version = 1; 187 if (guest_cpuid_has(vcpu, X86_FEATURE_PERFMON_V2)) { 188 pmu->version = 2; 189 /* 190 * Note, PERFMON_V2 is also in 0x80000022.0x0, i.e. the guest 191 * CPUID entry is guaranteed to be non-NULL. 192 */ 193 BUILD_BUG_ON(x86_feature_cpuid(X86_FEATURE_PERFMON_V2).function != 0x80000022 || 194 x86_feature_cpuid(X86_FEATURE_PERFMON_V2).index); 195 ebx.full = kvm_find_cpuid_entry_index(vcpu, 0x80000022, 0)->ebx; 196 pmu->nr_arch_gp_counters = ebx.split.num_core_pmc; 197 } else if (guest_cpuid_has(vcpu, X86_FEATURE_PERFCTR_CORE)) { 198 pmu->nr_arch_gp_counters = AMD64_NUM_COUNTERS_CORE; 199 } else { 200 pmu->nr_arch_gp_counters = AMD64_NUM_COUNTERS; 201 } 202 203 pmu->nr_arch_gp_counters = min_t(unsigned int, pmu->nr_arch_gp_counters, 204 kvm_pmu_cap.num_counters_gp); 205 206 if (pmu->version > 1) { 207 pmu->global_ctrl_mask = ~((1ull << pmu->nr_arch_gp_counters) - 1); 208 pmu->global_status_mask = pmu->global_ctrl_mask; 209 } 210 211 pmu->counter_bitmask[KVM_PMC_GP] = ((u64)1 << 48) - 1; 212 pmu->reserved_bits = 0xfffffff000280000ull; 213 pmu->raw_event_mask = AMD64_RAW_EVENT_MASK; 214 /* not applicable to AMD; but clean them to prevent any fall out */ 215 pmu->counter_bitmask[KVM_PMC_FIXED] = 0; 216 pmu->nr_arch_fixed_counters = 0; 217 bitmap_set(pmu->all_valid_pmc_idx, 0, pmu->nr_arch_gp_counters); 218 } 219 220 static void amd_pmu_init(struct kvm_vcpu *vcpu) 221 { 222 struct kvm_pmu *pmu = vcpu_to_pmu(vcpu); 223 int i; 224 225 BUILD_BUG_ON(KVM_AMD_PMC_MAX_GENERIC > AMD64_NUM_COUNTERS_CORE); 226 BUILD_BUG_ON(KVM_AMD_PMC_MAX_GENERIC > INTEL_PMC_MAX_GENERIC); 227 228 for (i = 0; i < KVM_AMD_PMC_MAX_GENERIC ; i++) { 229 pmu->gp_counters[i].type = KVM_PMC_GP; 230 pmu->gp_counters[i].vcpu = vcpu; 231 pmu->gp_counters[i].idx = i; 232 pmu->gp_counters[i].current_config = 0; 233 } 234 } 235 236 struct kvm_pmu_ops amd_pmu_ops __initdata = { 237 .hw_event_available = amd_hw_event_available, 238 .pmc_idx_to_pmc = amd_pmc_idx_to_pmc, 239 .rdpmc_ecx_to_pmc = amd_rdpmc_ecx_to_pmc, 240 .msr_idx_to_pmc = amd_msr_idx_to_pmc, 241 .is_valid_rdpmc_ecx = amd_is_valid_rdpmc_ecx, 242 .is_valid_msr = amd_is_valid_msr, 243 .get_msr = amd_pmu_get_msr, 244 .set_msr = amd_pmu_set_msr, 245 .refresh = amd_pmu_refresh, 246 .init = amd_pmu_init, 247 .EVENTSEL_EVENT = AMD64_EVENTSEL_EVENT, 248 .MAX_NR_GP_COUNTERS = KVM_AMD_PMC_MAX_GENERIC, 249 .MIN_NR_GP_COUNTERS = AMD64_NUM_COUNTERS, 250 }; 251