From: Jean-Philippe Brucker <[email protected]> Add a "num-pmu-counters" CPU parameter to configure the number of counters that KVM presents to the guest. This is needed for Realm VMs, whose parameters include the number of PMU counters and influence the Realm Initial Measurement.
Signed-off-by: Jean-Philippe Brucker <[email protected]> Signed-off-by: Mathieu Poirier <[email protected]> --- target/arm/arm-qmp-cmds.c | 2 +- target/arm/cpu.h | 3 +++ target/arm/cpu64.c | 41 +++++++++++++++++++++++++++++++++++++++ target/arm/kvm.c | 34 ++++++++++++++++++++++++++++++++ 4 files changed, 79 insertions(+), 1 deletion(-) diff --git a/target/arm/arm-qmp-cmds.c b/target/arm/arm-qmp-cmds.c index 9ed65eb090d7..9350dc30d12f 100644 --- a/target/arm/arm-qmp-cmds.c +++ b/target/arm/arm-qmp-cmds.c @@ -76,7 +76,7 @@ static const char *cpu_model_advertised_features[] = { "sve1408", "sve1536", "sve1664", "sve1792", "sve1920", "sve2048", "kvm-no-adjvtime", "kvm-steal-time", "pauth", "pauth-impdef", "pauth-qarma3", "pauth-qarma5", - "num-breakpoints", "num-watchpoints", + "num-breakpoints", "num-watchpoints", "num-pmu-counters", NULL }; diff --git a/target/arm/cpu.h b/target/arm/cpu.h index 2e41c2be3b71..a5b8b7ccc70b 100644 --- a/target/arm/cpu.h +++ b/target/arm/cpu.h @@ -1201,6 +1201,7 @@ struct ArchCPU { /* Allows to override the default configuration */ uint8_t num_bps; uint8_t num_wps; + int8_t num_pmu_ctrs; }; typedef struct ARMCPUInfo { @@ -2158,6 +2159,8 @@ FIELD(MFAR, FPA, 12, 40) FIELD(MFAR, NSE, 62, 1) FIELD(MFAR, NS, 63, 1) +FIELD(PMCR, N, 11, 5) + /* If adding a feature bit which corresponds to a Linux ELF * HWCAP bit, remember to update the feature-bit-to-hwcap * mapping in linux-user/elfload.c:get_elf_hwcap(). diff --git a/target/arm/cpu64.c b/target/arm/cpu64.c index 483441dfabe3..22a8394a9f4e 100644 --- a/target/arm/cpu64.c +++ b/target/arm/cpu64.c @@ -745,12 +745,53 @@ static void arm_cpu_set_num_bps(Object *obj, Visitor *v, const char *name, cpu->num_bps = val; } +static void arm_cpu_get_num_pmu_ctrs(Object *obj, Visitor *v, const char *name, + void *opaque, Error **errp) +{ + uint8_t val; + ARMCPU *cpu = ARM_CPU(obj); + + if (cpu->num_pmu_ctrs == -1) { + val = FIELD_EX64(cpu->isar.reset_pmcr_el0, PMCR, N); + } else { + val = cpu->num_pmu_ctrs; + } + + visit_type_uint8(v, name, &val, errp); +} + +static void arm_cpu_set_num_pmu_ctrs(Object *obj, Visitor *v, const char *name, + void *opaque, Error **errp) +{ + uint8_t val; + ARMCPU *cpu = ARM_CPU(obj); + uint8_t max_ctrs = FIELD_EX64(cpu->isar.reset_pmcr_el0, PMCR, N); + + if (!visit_type_uint8(v, name, &val, errp)) { + return; + } + + if (val > max_ctrs) { + error_setg(errp, "invalid number of PMU counters"); + return; + } + + cpu->num_pmu_ctrs = val; +} + static void aarch64_add_kvm_writable_properties(Object *obj) { + ARMCPU *cpu = ARM_CPU(obj); + object_property_add(obj, "num-breakpoints", "uint8", arm_cpu_get_num_bps, arm_cpu_set_num_bps, NULL, NULL); object_property_add(obj, "num-watchpoints", "uint8", arm_cpu_get_num_wps, arm_cpu_set_num_wps, NULL, NULL); + + cpu->num_pmu_ctrs = -1; + object_property_add(obj, "num-pmu-counters", "uint8", + arm_cpu_get_num_pmu_ctrs, arm_cpu_set_num_pmu_ctrs, + NULL, NULL); } #endif /* CONFIG_KVM */ diff --git a/target/arm/kvm.c b/target/arm/kvm.c index 1acf62545e7a..28d00f520e9f 100644 --- a/target/arm/kvm.c +++ b/target/arm/kvm.c @@ -1000,9 +1000,43 @@ static void kvm_arm_configure_aa64dfr0(ARMCPU *cpu) } } +#define KVM_REG_ARM_PMCR_EL0 ARM64_SYS_REG(3, 3, 9, 12, 0) + +static void kvm_arm_configure_pmcr(ARMCPU *cpu) +{ + int ret; + uint64_t val, newval; + CPUState *cs = CPU(cpu); + + if (cpu->num_pmu_ctrs == -1) { + return; + } + + newval = FIELD_DP64(cpu->isar.reset_pmcr_el0, PMCR, N, cpu->num_pmu_ctrs); + ret = kvm_set_one_reg(cs, KVM_REG_ARM_PMCR_EL0, &newval); + if (ret) { + error_report("Failed to set KVM_REG_ARM_PMCR_EL0"); + return; + } + + /* + * Check if the write succeeded, since older versions of KVM ignore it. + */ + ret = kvm_get_one_reg(cs, KVM_REG_ARM_PMCR_EL0, &val); + if (ret) { + error_report("Failed to get KVM_REG_ARM_PMCR_EL0"); + return; + } + + if (val != newval) { + error_report("Failed to update KVM_REG_ARM_PMCR_EL0"); + } +} + static void kvm_arm_configure_vcpu_regs(ARMCPU *cpu) { kvm_arm_configure_aa64dfr0(cpu); + kvm_arm_configure_pmcr(cpu); } /** -- 2.43.0
