On Fri, Aug 25, 2023 at 10:08:52AM -0300, Daniel Henrique Barboza wrote:
> This property indicates if a CPU supports TCG acceleration. All CPUs but
> the 'host' CPU supports it.
>
> The error in tcg_cpu_realizefn() can now be made generic in case more
> non-TCG CPUs are added in the future.
>
> Signed-off-by: Daniel Henrique Barboza
> ---
> target/riscv/cpu-qom.h | 1 +
> target/riscv/cpu.c | 10 ++
> target/riscv/cpu.h | 1 +
> target/riscv/tcg/tcg-cpu.c | 7 +--
> 4 files changed, 17 insertions(+), 2 deletions(-)
>
> diff --git a/target/riscv/cpu-qom.h b/target/riscv/cpu-qom.h
> index 7c76dc0dcc..e86b76f9fe 100644
> --- a/target/riscv/cpu-qom.h
> +++ b/target/riscv/cpu-qom.h
> @@ -71,5 +71,6 @@ struct RISCVCPUClass {
> ResettablePhases parent_phases;
>
> bool user_extension_properties;
> +bool tcg_supported;
> };
> #endif /* RISCV_CPU_QOM_H */
> diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
> index 6817f94c2c..f749ea2a2e 100644
> --- a/target/riscv/cpu.c
> +++ b/target/riscv/cpu.c
> @@ -625,6 +625,14 @@ static void rv32_imafcu_nommu_cpu_init(Object *obj)
> }
> #endif
>
> +char *riscv_cpu_get_name(RISCVCPUClass *rcc)
> +{
> +const char *typename = object_class_get_name(OBJECT_CLASS(rcc));
> +
> +return g_strndup(typename,
> + strlen(typename) - strlen("-" TYPE_RISCV_CPU));
RISCV_CPU_TYPE_SUFFIX
Could also add the assert like x86 has in x86_cpu_class_get_model_name()
> +}
> +
> static ObjectClass *riscv_cpu_class_by_name(const char *cpu_model)
> {
> ObjectClass *oc;
> @@ -1637,6 +1645,7 @@ static void riscv_dynamic_cpu_class_init(ObjectClass
> *c, void *data)
> RISCVCPUClass *rcc = RISCV_CPU_CLASS(c);
>
> rcc->user_extension_properties = true;
> +rcc->tcg_supported = true;
Rather than add this tcg_supported to most (all but 'host'?) cpus, what
about doing what x86 does and create an 'accel_uses_host_cpuid()' function
which is checked in realize?
> }
>
> static void riscv_vendor_cpu_class_init(ObjectClass *c, void *data)
> @@ -1644,6 +1653,7 @@ static void riscv_vendor_cpu_class_init(ObjectClass *c,
> void *data)
> RISCVCPUClass *rcc = RISCV_CPU_CLASS(c);
>
> rcc->user_extension_properties = false;
> +rcc->tcg_supported = true;
> }
>
> #define DEFINE_DYNAMIC_CPU(type_name, initfn) \
> diff --git a/target/riscv/cpu.h b/target/riscv/cpu.h
> index 4254f04684..1e6ecf52ee 100644
> --- a/target/riscv/cpu.h
> +++ b/target/riscv/cpu.h
> @@ -732,6 +732,7 @@ typedef struct isa_ext_data {
> extern const RISCVIsaExtData isa_edata_arr[];
>
> void riscv_add_satp_mode_properties(Object *obj);
> +char *riscv_cpu_get_name(RISCVCPUClass *rcc);
>
> /* CSR function table */
> extern riscv_csr_operations csr_ops[CSR_TABLE_SIZE];
> diff --git a/target/riscv/tcg/tcg-cpu.c b/target/riscv/tcg/tcg-cpu.c
> index 6c91978920..a13796c597 100644
> --- a/target/riscv/tcg/tcg-cpu.c
> +++ b/target/riscv/tcg/tcg-cpu.c
> @@ -554,11 +554,14 @@ void riscv_cpu_validate_set_extensions(RISCVCPU *cpu,
> Error **errp)
> static bool tcg_cpu_realizefn(CPUState *cs, Error **errp)
> {
> RISCVCPU *cpu = RISCV_CPU(cs);
> +RISCVCPUClass *rcc = RISCV_CPU_GET_CLASS(cpu);
> CPURISCVState *env = >env;
> Error *local_err = NULL;
>
> -if (object_dynamic_cast(OBJECT(cpu), TYPE_RISCV_CPU_HOST)) {
> -error_setg(errp, "'host' CPU is not compatible with TCG
> acceleration");
> +if (!rcc->tcg_supported) {
> +g_autofree char *name = riscv_cpu_get_name(rcc);
> +error_setg(errp, "'%s' CPU is not compatible with TCG acceleration",
> + name);
> return false;
> }
>
> --
> 2.41.0
>
>
Thanks,
drew
