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([187.217.227.247]) by smtp.gmail.com with ESMTPSA id i7-20020a056808030700b003b8347de3c2sm73888oie.19.2023.11.22.20.42.30 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 22 Nov 2023 20:42:31 -0800 (PST) From: Richard Henderson To: qemu-devel@nongnu.org Cc: qemu-arm@nongnu.org Subject: [PATCH 10/21] target/arm/kvm: Move kvm_arm_get_host_cpu_features and unexport Date: Wed, 22 Nov 2023 22:42:08 -0600 Message-Id: <20231123044219.896776-11-richard.henderson@linaro.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231123044219.896776-1-richard.henderson@linaro.org> References: <20231123044219.896776-1-richard.henderson@linaro.org> MIME-Version: 1.0 Received-SPF: pass client-ip=2607:f8b0:4864:20::22c; envelope-from=richard.henderson@linaro.org; helo=mail-oi1-x22c.google.com X-Spam_score_int: 12 X-Spam_score: 1.2 X-Spam_bar: + X-Spam_report: (1.2 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_SBL_CSS=3.335, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Signed-off-by: Richard Henderson Reviewed-by: Philippe Mathieu-Daudé Reviewed-by: Gavin Shan --- target/arm/kvm_arm.h | 22 ---- target/arm/kvm.c | 265 +++++++++++++++++++++++++++++++++++++++++++ target/arm/kvm64.c | 254 ----------------------------------------- 3 files changed, 265 insertions(+), 276 deletions(-) diff --git a/target/arm/kvm_arm.h b/target/arm/kvm_arm.h index 58c087207f..e59d713973 100644 --- a/target/arm/kvm_arm.h +++ b/target/arm/kvm_arm.h @@ -214,28 +214,6 @@ bool kvm_arm_create_scratch_host_vcpu(const uint32_t *cpus_to_try, */ void kvm_arm_destroy_scratch_host_vcpu(int *fdarray); -/** - * ARMHostCPUFeatures: information about the host CPU (identified - * by asking the host kernel) - */ -typedef struct ARMHostCPUFeatures { - ARMISARegisters isar; - uint64_t features; - uint32_t target; - const char *dtb_compatible; -} ARMHostCPUFeatures; - -/** - * kvm_arm_get_host_cpu_features: - * @ahcf: ARMHostCPUClass to fill in - * - * Probe the capabilities of the host kernel's preferred CPU and fill - * in the ARMHostCPUClass struct accordingly. - * - * Returns true on success and false otherwise. - */ -bool kvm_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf); - /** * kvm_arm_sve_get_vls: * @cs: CPUState diff --git a/target/arm/kvm.c b/target/arm/kvm.c index 84f300c602..ffe0db4293 100644 --- a/target/arm/kvm.c +++ b/target/arm/kvm.c @@ -41,6 +41,17 @@ static bool cap_has_mp_state; static bool cap_has_inject_serror_esr; static bool cap_has_inject_ext_dabt; +/** + * ARMHostCPUFeatures: information about the host CPU (identified + * by asking the host kernel) + */ +typedef struct ARMHostCPUFeatures { + ARMISARegisters isar; + uint64_t features; + uint32_t target; + const char *dtb_compatible; +} ARMHostCPUFeatures; + static ARMHostCPUFeatures arm_host_cpu_features; int kvm_arm_vcpu_init(CPUState *cs) @@ -167,6 +178,260 @@ void kvm_arm_destroy_scratch_host_vcpu(int *fdarray) } } +static int read_sys_reg32(int fd, uint32_t *pret, uint64_t id) +{ + uint64_t ret; + struct kvm_one_reg idreg = { .id = id, .addr = (uintptr_t)&ret }; + int err; + + assert((id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64); + err = ioctl(fd, KVM_GET_ONE_REG, &idreg); + if (err < 0) { + return -1; + } + *pret = ret; + return 0; +} + +static int read_sys_reg64(int fd, uint64_t *pret, uint64_t id) +{ + struct kvm_one_reg idreg = { .id = id, .addr = (uintptr_t)pret }; + + assert((id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64); + return ioctl(fd, KVM_GET_ONE_REG, &idreg); +} + +static bool kvm_arm_pauth_supported(void) +{ + return (kvm_check_extension(kvm_state, KVM_CAP_ARM_PTRAUTH_ADDRESS) && + kvm_check_extension(kvm_state, KVM_CAP_ARM_PTRAUTH_GENERIC)); +} + +static bool kvm_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf) +{ + /* Identify the feature bits corresponding to the host CPU, and + * fill out the ARMHostCPUClass fields accordingly. To do this + * we have to create a scratch VM, create a single CPU inside it, + * and then query that CPU for the relevant ID registers. + */ + int fdarray[3]; + bool sve_supported; + bool pmu_supported = false; + uint64_t features = 0; + int err; + + /* Old kernels may not know about the PREFERRED_TARGET ioctl: however + * we know these will only support creating one kind of guest CPU, + * which is its preferred CPU type. Fortunately these old kernels + * support only a very limited number of CPUs. + */ + static const uint32_t cpus_to_try[] = { + KVM_ARM_TARGET_AEM_V8, + KVM_ARM_TARGET_FOUNDATION_V8, + KVM_ARM_TARGET_CORTEX_A57, + QEMU_KVM_ARM_TARGET_NONE + }; + /* + * target = -1 informs kvm_arm_create_scratch_host_vcpu() + * to use the preferred target + */ + struct kvm_vcpu_init init = { .target = -1, }; + + /* + * Ask for SVE if supported, so that we can query ID_AA64ZFR0, + * which is otherwise RAZ. + */ + sve_supported = kvm_arm_sve_supported(); + if (sve_supported) { + init.features[0] |= 1 << KVM_ARM_VCPU_SVE; + } + + /* + * Ask for Pointer Authentication if supported, so that we get + * the unsanitized field values for AA64ISAR1_EL1. + */ + if (kvm_arm_pauth_supported()) { + init.features[0] |= (1 << KVM_ARM_VCPU_PTRAUTH_ADDRESS | + 1 << KVM_ARM_VCPU_PTRAUTH_GENERIC); + } + + if (kvm_arm_pmu_supported()) { + init.features[0] |= 1 << KVM_ARM_VCPU_PMU_V3; + pmu_supported = true; + } + + if (!kvm_arm_create_scratch_host_vcpu(cpus_to_try, fdarray, &init)) { + return false; + } + + ahcf->target = init.target; + ahcf->dtb_compatible = "arm,arm-v8"; + + err = read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64pfr0, + ARM64_SYS_REG(3, 0, 0, 4, 0)); + if (unlikely(err < 0)) { + /* + * Before v4.15, the kernel only exposed a limited number of system + * registers, not including any of the interesting AArch64 ID regs. + * For the most part we could leave these fields as zero with minimal + * effect, since this does not affect the values seen by the guest. + * + * However, it could cause problems down the line for QEMU, + * so provide a minimal v8.0 default. + * + * ??? Could read MIDR and use knowledge from cpu64.c. + * ??? Could map a page of memory into our temp guest and + * run the tiniest of hand-crafted kernels to extract + * the values seen by the guest. + * ??? Either of these sounds like too much effort just + * to work around running a modern host kernel. + */ + ahcf->isar.id_aa64pfr0 = 0x00000011; /* EL1&0, AArch64 only */ + err = 0; + } else { + err |= read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64pfr1, + ARM64_SYS_REG(3, 0, 0, 4, 1)); + err |= read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64smfr0, + ARM64_SYS_REG(3, 0, 0, 4, 5)); + err |= read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64dfr0, + ARM64_SYS_REG(3, 0, 0, 5, 0)); + err |= read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64dfr1, + ARM64_SYS_REG(3, 0, 0, 5, 1)); + err |= read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64isar0, + ARM64_SYS_REG(3, 0, 0, 6, 0)); + err |= read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64isar1, + ARM64_SYS_REG(3, 0, 0, 6, 1)); + err |= read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64isar2, + ARM64_SYS_REG(3, 0, 0, 6, 2)); + err |= read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64mmfr0, + ARM64_SYS_REG(3, 0, 0, 7, 0)); + err |= read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64mmfr1, + ARM64_SYS_REG(3, 0, 0, 7, 1)); + err |= read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64mmfr2, + ARM64_SYS_REG(3, 0, 0, 7, 2)); + + /* + * Note that if AArch32 support is not present in the host, + * the AArch32 sysregs are present to be read, but will + * return UNKNOWN values. This is neither better nor worse + * than skipping the reads and leaving 0, as we must avoid + * considering the values in every case. + */ + err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_pfr0, + ARM64_SYS_REG(3, 0, 0, 1, 0)); + err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_pfr1, + ARM64_SYS_REG(3, 0, 0, 1, 1)); + err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_dfr0, + ARM64_SYS_REG(3, 0, 0, 1, 2)); + err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_mmfr0, + ARM64_SYS_REG(3, 0, 0, 1, 4)); + err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_mmfr1, + ARM64_SYS_REG(3, 0, 0, 1, 5)); + err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_mmfr2, + ARM64_SYS_REG(3, 0, 0, 1, 6)); + err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_mmfr3, + ARM64_SYS_REG(3, 0, 0, 1, 7)); + err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_isar0, + ARM64_SYS_REG(3, 0, 0, 2, 0)); + err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_isar1, + ARM64_SYS_REG(3, 0, 0, 2, 1)); + err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_isar2, + ARM64_SYS_REG(3, 0, 0, 2, 2)); + err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_isar3, + ARM64_SYS_REG(3, 0, 0, 2, 3)); + err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_isar4, + ARM64_SYS_REG(3, 0, 0, 2, 4)); + err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_isar5, + ARM64_SYS_REG(3, 0, 0, 2, 5)); + err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_mmfr4, + ARM64_SYS_REG(3, 0, 0, 2, 6)); + err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_isar6, + ARM64_SYS_REG(3, 0, 0, 2, 7)); + + err |= read_sys_reg32(fdarray[2], &ahcf->isar.mvfr0, + ARM64_SYS_REG(3, 0, 0, 3, 0)); + err |= read_sys_reg32(fdarray[2], &ahcf->isar.mvfr1, + ARM64_SYS_REG(3, 0, 0, 3, 1)); + err |= read_sys_reg32(fdarray[2], &ahcf->isar.mvfr2, + ARM64_SYS_REG(3, 0, 0, 3, 2)); + err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_pfr2, + ARM64_SYS_REG(3, 0, 0, 3, 4)); + err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_dfr1, + ARM64_SYS_REG(3, 0, 0, 3, 5)); + err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_mmfr5, + ARM64_SYS_REG(3, 0, 0, 3, 6)); + + /* + * DBGDIDR is a bit complicated because the kernel doesn't + * provide an accessor for it in 64-bit mode, which is what this + * scratch VM is in, and there's no architected "64-bit sysreg + * which reads the same as the 32-bit register" the way there is + * for other ID registers. Instead we synthesize a value from the + * AArch64 ID_AA64DFR0, the same way the kernel code in + * arch/arm64/kvm/sys_regs.c:trap_dbgidr() does. + * We only do this if the CPU supports AArch32 at EL1. + */ + if (FIELD_EX32(ahcf->isar.id_aa64pfr0, ID_AA64PFR0, EL1) >= 2) { + int wrps = FIELD_EX64(ahcf->isar.id_aa64dfr0, ID_AA64DFR0, WRPS); + int brps = FIELD_EX64(ahcf->isar.id_aa64dfr0, ID_AA64DFR0, BRPS); + int ctx_cmps = + FIELD_EX64(ahcf->isar.id_aa64dfr0, ID_AA64DFR0, CTX_CMPS); + int version = 6; /* ARMv8 debug architecture */ + bool has_el3 = + !!FIELD_EX32(ahcf->isar.id_aa64pfr0, ID_AA64PFR0, EL3); + uint32_t dbgdidr = 0; + + dbgdidr = FIELD_DP32(dbgdidr, DBGDIDR, WRPS, wrps); + dbgdidr = FIELD_DP32(dbgdidr, DBGDIDR, BRPS, brps); + dbgdidr = FIELD_DP32(dbgdidr, DBGDIDR, CTX_CMPS, ctx_cmps); + dbgdidr = FIELD_DP32(dbgdidr, DBGDIDR, VERSION, version); + dbgdidr = FIELD_DP32(dbgdidr, DBGDIDR, NSUHD_IMP, has_el3); + dbgdidr = FIELD_DP32(dbgdidr, DBGDIDR, SE_IMP, has_el3); + dbgdidr |= (1 << 15); /* RES1 bit */ + ahcf->isar.dbgdidr = dbgdidr; + } + + if (pmu_supported) { + /* PMCR_EL0 is only accessible if the vCPU has feature PMU_V3 */ + err |= read_sys_reg64(fdarray[2], &ahcf->isar.reset_pmcr_el0, + ARM64_SYS_REG(3, 3, 9, 12, 0)); + } + + if (sve_supported) { + /* + * There is a range of kernels between kernel commit 73433762fcae + * and f81cb2c3ad41 which have a bug where the kernel doesn't + * expose SYS_ID_AA64ZFR0_EL1 via the ONE_REG API unless the VM has + * enabled SVE support, which resulted in an error rather than RAZ. + * So only read the register if we set KVM_ARM_VCPU_SVE above. + */ + err |= read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64zfr0, + ARM64_SYS_REG(3, 0, 0, 4, 4)); + } + } + + kvm_arm_destroy_scratch_host_vcpu(fdarray); + + if (err < 0) { + return false; + } + + /* + * We can assume any KVM supporting CPU is at least a v8 + * with VFPv4+Neon; this in turn implies most of the other + * feature bits. + */ + features |= 1ULL << ARM_FEATURE_V8; + features |= 1ULL << ARM_FEATURE_NEON; + features |= 1ULL << ARM_FEATURE_AARCH64; + features |= 1ULL << ARM_FEATURE_PMU; + features |= 1ULL << ARM_FEATURE_GENERIC_TIMER; + + ahcf->features = features; + + return true; +} + void kvm_arm_set_cpu_features_from_host(ARMCPU *cpu) { CPUARMState *env = &cpu->env; diff --git a/target/arm/kvm64.c b/target/arm/kvm64.c index fca4864b73..504526b24c 100644 --- a/target/arm/kvm64.c +++ b/target/arm/kvm64.c @@ -143,260 +143,6 @@ void kvm_arm_pvtime_init(CPUState *cs, uint64_t ipa) } } -static int read_sys_reg32(int fd, uint32_t *pret, uint64_t id) -{ - uint64_t ret; - struct kvm_one_reg idreg = { .id = id, .addr = (uintptr_t)&ret }; - int err; - - assert((id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64); - err = ioctl(fd, KVM_GET_ONE_REG, &idreg); - if (err < 0) { - return -1; - } - *pret = ret; - return 0; -} - -static int read_sys_reg64(int fd, uint64_t *pret, uint64_t id) -{ - struct kvm_one_reg idreg = { .id = id, .addr = (uintptr_t)pret }; - - assert((id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64); - return ioctl(fd, KVM_GET_ONE_REG, &idreg); -} - -static bool kvm_arm_pauth_supported(void) -{ - return (kvm_check_extension(kvm_state, KVM_CAP_ARM_PTRAUTH_ADDRESS) && - kvm_check_extension(kvm_state, KVM_CAP_ARM_PTRAUTH_GENERIC)); -} - -bool kvm_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf) -{ - /* Identify the feature bits corresponding to the host CPU, and - * fill out the ARMHostCPUClass fields accordingly. To do this - * we have to create a scratch VM, create a single CPU inside it, - * and then query that CPU for the relevant ID registers. - */ - int fdarray[3]; - bool sve_supported; - bool pmu_supported = false; - uint64_t features = 0; - int err; - - /* Old kernels may not know about the PREFERRED_TARGET ioctl: however - * we know these will only support creating one kind of guest CPU, - * which is its preferred CPU type. Fortunately these old kernels - * support only a very limited number of CPUs. - */ - static const uint32_t cpus_to_try[] = { - KVM_ARM_TARGET_AEM_V8, - KVM_ARM_TARGET_FOUNDATION_V8, - KVM_ARM_TARGET_CORTEX_A57, - QEMU_KVM_ARM_TARGET_NONE - }; - /* - * target = -1 informs kvm_arm_create_scratch_host_vcpu() - * to use the preferred target - */ - struct kvm_vcpu_init init = { .target = -1, }; - - /* - * Ask for SVE if supported, so that we can query ID_AA64ZFR0, - * which is otherwise RAZ. - */ - sve_supported = kvm_arm_sve_supported(); - if (sve_supported) { - init.features[0] |= 1 << KVM_ARM_VCPU_SVE; - } - - /* - * Ask for Pointer Authentication if supported, so that we get - * the unsanitized field values for AA64ISAR1_EL1. - */ - if (kvm_arm_pauth_supported()) { - init.features[0] |= (1 << KVM_ARM_VCPU_PTRAUTH_ADDRESS | - 1 << KVM_ARM_VCPU_PTRAUTH_GENERIC); - } - - if (kvm_arm_pmu_supported()) { - init.features[0] |= 1 << KVM_ARM_VCPU_PMU_V3; - pmu_supported = true; - } - - if (!kvm_arm_create_scratch_host_vcpu(cpus_to_try, fdarray, &init)) { - return false; - } - - ahcf->target = init.target; - ahcf->dtb_compatible = "arm,arm-v8"; - - err = read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64pfr0, - ARM64_SYS_REG(3, 0, 0, 4, 0)); - if (unlikely(err < 0)) { - /* - * Before v4.15, the kernel only exposed a limited number of system - * registers, not including any of the interesting AArch64 ID regs. - * For the most part we could leave these fields as zero with minimal - * effect, since this does not affect the values seen by the guest. - * - * However, it could cause problems down the line for QEMU, - * so provide a minimal v8.0 default. - * - * ??? Could read MIDR and use knowledge from cpu64.c. - * ??? Could map a page of memory into our temp guest and - * run the tiniest of hand-crafted kernels to extract - * the values seen by the guest. - * ??? Either of these sounds like too much effort just - * to work around running a modern host kernel. - */ - ahcf->isar.id_aa64pfr0 = 0x00000011; /* EL1&0, AArch64 only */ - err = 0; - } else { - err |= read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64pfr1, - ARM64_SYS_REG(3, 0, 0, 4, 1)); - err |= read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64smfr0, - ARM64_SYS_REG(3, 0, 0, 4, 5)); - err |= read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64dfr0, - ARM64_SYS_REG(3, 0, 0, 5, 0)); - err |= read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64dfr1, - ARM64_SYS_REG(3, 0, 0, 5, 1)); - err |= read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64isar0, - ARM64_SYS_REG(3, 0, 0, 6, 0)); - err |= read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64isar1, - ARM64_SYS_REG(3, 0, 0, 6, 1)); - err |= read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64isar2, - ARM64_SYS_REG(3, 0, 0, 6, 2)); - err |= read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64mmfr0, - ARM64_SYS_REG(3, 0, 0, 7, 0)); - err |= read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64mmfr1, - ARM64_SYS_REG(3, 0, 0, 7, 1)); - err |= read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64mmfr2, - ARM64_SYS_REG(3, 0, 0, 7, 2)); - - /* - * Note that if AArch32 support is not present in the host, - * the AArch32 sysregs are present to be read, but will - * return UNKNOWN values. This is neither better nor worse - * than skipping the reads and leaving 0, as we must avoid - * considering the values in every case. - */ - err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_pfr0, - ARM64_SYS_REG(3, 0, 0, 1, 0)); - err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_pfr1, - ARM64_SYS_REG(3, 0, 0, 1, 1)); - err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_dfr0, - ARM64_SYS_REG(3, 0, 0, 1, 2)); - err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_mmfr0, - ARM64_SYS_REG(3, 0, 0, 1, 4)); - err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_mmfr1, - ARM64_SYS_REG(3, 0, 0, 1, 5)); - err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_mmfr2, - ARM64_SYS_REG(3, 0, 0, 1, 6)); - err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_mmfr3, - ARM64_SYS_REG(3, 0, 0, 1, 7)); - err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_isar0, - ARM64_SYS_REG(3, 0, 0, 2, 0)); - err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_isar1, - ARM64_SYS_REG(3, 0, 0, 2, 1)); - err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_isar2, - ARM64_SYS_REG(3, 0, 0, 2, 2)); - err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_isar3, - ARM64_SYS_REG(3, 0, 0, 2, 3)); - err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_isar4, - ARM64_SYS_REG(3, 0, 0, 2, 4)); - err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_isar5, - ARM64_SYS_REG(3, 0, 0, 2, 5)); - err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_mmfr4, - ARM64_SYS_REG(3, 0, 0, 2, 6)); - err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_isar6, - ARM64_SYS_REG(3, 0, 0, 2, 7)); - - err |= read_sys_reg32(fdarray[2], &ahcf->isar.mvfr0, - ARM64_SYS_REG(3, 0, 0, 3, 0)); - err |= read_sys_reg32(fdarray[2], &ahcf->isar.mvfr1, - ARM64_SYS_REG(3, 0, 0, 3, 1)); - err |= read_sys_reg32(fdarray[2], &ahcf->isar.mvfr2, - ARM64_SYS_REG(3, 0, 0, 3, 2)); - err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_pfr2, - ARM64_SYS_REG(3, 0, 0, 3, 4)); - err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_dfr1, - ARM64_SYS_REG(3, 0, 0, 3, 5)); - err |= read_sys_reg32(fdarray[2], &ahcf->isar.id_mmfr5, - ARM64_SYS_REG(3, 0, 0, 3, 6)); - - /* - * DBGDIDR is a bit complicated because the kernel doesn't - * provide an accessor for it in 64-bit mode, which is what this - * scratch VM is in, and there's no architected "64-bit sysreg - * which reads the same as the 32-bit register" the way there is - * for other ID registers. Instead we synthesize a value from the - * AArch64 ID_AA64DFR0, the same way the kernel code in - * arch/arm64/kvm/sys_regs.c:trap_dbgidr() does. - * We only do this if the CPU supports AArch32 at EL1. - */ - if (FIELD_EX32(ahcf->isar.id_aa64pfr0, ID_AA64PFR0, EL1) >= 2) { - int wrps = FIELD_EX64(ahcf->isar.id_aa64dfr0, ID_AA64DFR0, WRPS); - int brps = FIELD_EX64(ahcf->isar.id_aa64dfr0, ID_AA64DFR0, BRPS); - int ctx_cmps = - FIELD_EX64(ahcf->isar.id_aa64dfr0, ID_AA64DFR0, CTX_CMPS); - int version = 6; /* ARMv8 debug architecture */ - bool has_el3 = - !!FIELD_EX32(ahcf->isar.id_aa64pfr0, ID_AA64PFR0, EL3); - uint32_t dbgdidr = 0; - - dbgdidr = FIELD_DP32(dbgdidr, DBGDIDR, WRPS, wrps); - dbgdidr = FIELD_DP32(dbgdidr, DBGDIDR, BRPS, brps); - dbgdidr = FIELD_DP32(dbgdidr, DBGDIDR, CTX_CMPS, ctx_cmps); - dbgdidr = FIELD_DP32(dbgdidr, DBGDIDR, VERSION, version); - dbgdidr = FIELD_DP32(dbgdidr, DBGDIDR, NSUHD_IMP, has_el3); - dbgdidr = FIELD_DP32(dbgdidr, DBGDIDR, SE_IMP, has_el3); - dbgdidr |= (1 << 15); /* RES1 bit */ - ahcf->isar.dbgdidr = dbgdidr; - } - - if (pmu_supported) { - /* PMCR_EL0 is only accessible if the vCPU has feature PMU_V3 */ - err |= read_sys_reg64(fdarray[2], &ahcf->isar.reset_pmcr_el0, - ARM64_SYS_REG(3, 3, 9, 12, 0)); - } - - if (sve_supported) { - /* - * There is a range of kernels between kernel commit 73433762fcae - * and f81cb2c3ad41 which have a bug where the kernel doesn't - * expose SYS_ID_AA64ZFR0_EL1 via the ONE_REG API unless the VM has - * enabled SVE support, which resulted in an error rather than RAZ. - * So only read the register if we set KVM_ARM_VCPU_SVE above. - */ - err |= read_sys_reg64(fdarray[2], &ahcf->isar.id_aa64zfr0, - ARM64_SYS_REG(3, 0, 0, 4, 4)); - } - } - - kvm_arm_destroy_scratch_host_vcpu(fdarray); - - if (err < 0) { - return false; - } - - /* - * We can assume any KVM supporting CPU is at least a v8 - * with VFPv4+Neon; this in turn implies most of the other - * feature bits. - */ - features |= 1ULL << ARM_FEATURE_V8; - features |= 1ULL << ARM_FEATURE_NEON; - features |= 1ULL << ARM_FEATURE_AARCH64; - features |= 1ULL << ARM_FEATURE_PMU; - features |= 1ULL << ARM_FEATURE_GENERIC_TIMER; - - ahcf->features = features; - - return true; -} - void kvm_arm_steal_time_finalize(ARMCPU *cpu, Error **errp) { bool has_steal_time = kvm_check_extension(kvm_state, KVM_CAP_STEAL_TIME);