At this moment we're not checking if the host has support for any specific CSR before doing get/put regs. This will cause problems if the host KVM doesn't support it (see [1] as an example).
We'll use the same approach done with the CPU extensions: read all known KVM CSRs during init() to check for availability, then read/write them if they are present. This will be made by either using get-reglist or by directly reading the CSRs. For now we'll just convert the CSRs to use a kvm_csr_cfg[] array, reusing the same KVMCPUConfig abstraction we use for extensions, and use the array in (get|put)_csr_regs() instead of manually listing them. A lot of boilerplate will be added but at least we'll automate the get/put procedure for CSRs, i.e. adding a new CSR in the future will be a matter of adding it in kvm_csr_regs[] and everything else will be taken care of. Despite all the code changes no behavioral change is made. [1] https://lore.kernel.org/qemu-riscv/CABJz62OfUDHYkQ0T3rGHStQprf1c7_E0qBLbLKhfv=+jb0s...@mail.gmail.com/ Signed-off-by: Daniel Henrique Barboza <dbarb...@ventanamicro.com> Reviewed-by: Andrew Jones <ajo...@ventanamicro.com> Acked-by: Alistair Francis <alistair.fran...@wdc.com> --- target/riscv/cpu.h | 1 + target/riscv/kvm/kvm-cpu.c | 121 ++++++++++++++++++++++++++----------- 2 files changed, 86 insertions(+), 36 deletions(-) diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h index 679f417336..f5a60d0c52 100644 --- a/target/riscv/cpu.h +++ b/target/riscv/cpu.h @@ -79,6 +79,7 @@ const char *riscv_get_misa_ext_name(uint32_t bit); const char *riscv_get_misa_ext_description(uint32_t bit); #define CPU_CFG_OFFSET(_prop) offsetof(struct RISCVCPUConfig, _prop) +#define ENV_CSR_OFFSET(_csr) offsetof(CPURISCVState, _csr) typedef struct riscv_cpu_profile { struct riscv_cpu_profile *u_parent; diff --git a/target/riscv/kvm/kvm-cpu.c b/target/riscv/kvm/kvm-cpu.c index fd66bc1759..f881e7eb5d 100644 --- a/target/riscv/kvm/kvm-cpu.c +++ b/target/riscv/kvm/kvm-cpu.c @@ -114,22 +114,6 @@ static uint64_t kvm_riscv_vector_reg_id(RISCVCPU *cpu, KVM_RISCV_REG_ID_ULONG(KVM_REG_RISCV_VECTOR, \ KVM_REG_RISCV_VECTOR_CSR_REG(name)) -#define KVM_RISCV_GET_CSR(cs, env, csr, reg) \ - do { \ - int _ret = kvm_get_one_reg(cs, RISCV_CSR_REG(csr), ®); \ - if (_ret) { \ - return _ret; \ - } \ - } while (0) - -#define KVM_RISCV_SET_CSR(cs, env, csr, reg) \ - do { \ - int _ret = kvm_set_one_reg(cs, RISCV_CSR_REG(csr), ®); \ - if (_ret) { \ - return _ret; \ - } \ - } while (0) - #define KVM_RISCV_GET_TIMER(cs, name, reg) \ do { \ int ret = kvm_get_one_reg(cs, RISCV_TIMER_REG(name), ®); \ @@ -251,6 +235,53 @@ static void kvm_riscv_update_cpu_misa_ext(RISCVCPU *cpu, CPUState *cs) } } +#define KVM_CSR_CFG(_name, _env_prop, reg_id) \ + {.name = _name, .offset = ENV_CSR_OFFSET(_env_prop), \ + .kvm_reg_id = reg_id} + +static KVMCPUConfig kvm_csr_cfgs[] = { + KVM_CSR_CFG("sstatus", mstatus, RISCV_CSR_REG(sstatus)), + KVM_CSR_CFG("sie", mie, RISCV_CSR_REG(sie)), + KVM_CSR_CFG("stvec", stvec, RISCV_CSR_REG(stvec)), + KVM_CSR_CFG("sscratch", sscratch, RISCV_CSR_REG(sscratch)), + KVM_CSR_CFG("sepc", sepc, RISCV_CSR_REG(sepc)), + KVM_CSR_CFG("scause", scause, RISCV_CSR_REG(scause)), + KVM_CSR_CFG("stval", stval, RISCV_CSR_REG(stval)), + KVM_CSR_CFG("sip", mip, RISCV_CSR_REG(sip)), + KVM_CSR_CFG("satp", satp, RISCV_CSR_REG(satp)), +}; + +static void *kvmconfig_get_env_addr(RISCVCPU *cpu, KVMCPUConfig *csr_cfg) +{ + return (void *)&cpu->env + csr_cfg->offset; +} + +static uint32_t kvm_cpu_csr_get_u32(RISCVCPU *cpu, KVMCPUConfig *csr_cfg) +{ + uint32_t *val32 = kvmconfig_get_env_addr(cpu, csr_cfg); + return *val32; +} + +static uint64_t kvm_cpu_csr_get_u64(RISCVCPU *cpu, KVMCPUConfig *csr_cfg) +{ + uint64_t *val64 = kvmconfig_get_env_addr(cpu, csr_cfg); + return *val64; +} + +static void kvm_cpu_csr_set_u32(RISCVCPU *cpu, KVMCPUConfig *csr_cfg, + uint32_t val) +{ + uint32_t *val32 = kvmconfig_get_env_addr(cpu, csr_cfg); + *val32 = val; +} + +static void kvm_cpu_csr_set_u64(RISCVCPU *cpu, KVMCPUConfig *csr_cfg, + uint64_t val) +{ + uint64_t *val64 = kvmconfig_get_env_addr(cpu, csr_cfg); + *val64 = val; +} + #define KVM_EXT_CFG(_name, _prop, _reg_id) \ {.name = _name, .offset = CPU_CFG_OFFSET(_prop), \ .kvm_reg_id = _reg_id} @@ -598,34 +629,52 @@ static int kvm_riscv_put_regs_core(CPUState *cs) static int kvm_riscv_get_regs_csr(CPUState *cs) { - CPURISCVState *env = &RISCV_CPU(cs)->env; + RISCVCPU *cpu = RISCV_CPU(cs); + uint64_t reg; + int i, ret; + + for (i = 0; i < ARRAY_SIZE(kvm_csr_cfgs); i++) { + KVMCPUConfig *csr_cfg = &kvm_csr_cfgs[i]; - KVM_RISCV_GET_CSR(cs, env, sstatus, env->mstatus); - KVM_RISCV_GET_CSR(cs, env, sie, env->mie); - KVM_RISCV_GET_CSR(cs, env, stvec, env->stvec); - KVM_RISCV_GET_CSR(cs, env, sscratch, env->sscratch); - KVM_RISCV_GET_CSR(cs, env, sepc, env->sepc); - KVM_RISCV_GET_CSR(cs, env, scause, env->scause); - KVM_RISCV_GET_CSR(cs, env, stval, env->stval); - KVM_RISCV_GET_CSR(cs, env, sip, env->mip); - KVM_RISCV_GET_CSR(cs, env, satp, env->satp); + ret = kvm_get_one_reg(cs, csr_cfg->kvm_reg_id, ®); + if (ret) { + return ret; + } + + if (KVM_REG_SIZE(csr_cfg->kvm_reg_id) == sizeof(uint32_t)) { + kvm_cpu_csr_set_u32(cpu, csr_cfg, reg); + } else if (KVM_REG_SIZE(csr_cfg->kvm_reg_id) == sizeof(uint64_t)) { + kvm_cpu_csr_set_u64(cpu, csr_cfg, reg); + } else { + g_assert_not_reached(); + } + } return 0; } static int kvm_riscv_put_regs_csr(CPUState *cs) { - CPURISCVState *env = &RISCV_CPU(cs)->env; + RISCVCPU *cpu = RISCV_CPU(cs); + uint64_t reg; + int i, ret; + + for (i = 0; i < ARRAY_SIZE(kvm_csr_cfgs); i++) { + KVMCPUConfig *csr_cfg = &kvm_csr_cfgs[i]; + + if (KVM_REG_SIZE(csr_cfg->kvm_reg_id) == sizeof(uint32_t)) { + reg = kvm_cpu_csr_get_u32(cpu, csr_cfg); + } else if (KVM_REG_SIZE(csr_cfg->kvm_reg_id) == sizeof(uint64_t)) { + reg = kvm_cpu_csr_get_u64(cpu, csr_cfg); + } else { + g_assert_not_reached(); + } - KVM_RISCV_SET_CSR(cs, env, sstatus, env->mstatus); - KVM_RISCV_SET_CSR(cs, env, sie, env->mie); - KVM_RISCV_SET_CSR(cs, env, stvec, env->stvec); - KVM_RISCV_SET_CSR(cs, env, sscratch, env->sscratch); - KVM_RISCV_SET_CSR(cs, env, sepc, env->sepc); - KVM_RISCV_SET_CSR(cs, env, scause, env->scause); - KVM_RISCV_SET_CSR(cs, env, stval, env->stval); - KVM_RISCV_SET_CSR(cs, env, sip, env->mip); - KVM_RISCV_SET_CSR(cs, env, satp, env->satp); + ret = kvm_set_one_reg(cs, csr_cfg->kvm_reg_id, ®); + if (ret) { + return ret; + } + } return 0; } -- 2.49.0
