On Mon, Dec 18, 2023 at 10:58 PM Daniel Henrique Barboza
<dbarb...@ventanamicro.com> wrote:
>
> We'll add a new bare CPU type that won't have any default priv_ver. This
> means that the CPU will default to priv_ver = 0, i.e. 1.10.0.
>
> At the same we'll allow these CPUs to enable extensions at will, but
> then, if the extension has a priv_ver newer than 1.10, we'll end up
> disabling it. Users will then need to manually set priv_ver to something
> other than 1.10 to enable the extensions they want, which is not ideal.
>
> Change the setter() of extensions to allow user enabled extensions to
> bump the priv_ver of the CPU. This will make it convenient for users to
> enable extensions for CPUs that doesn't set a default priv_ver.
>
> This change does not affect any existing CPU: vendor CPUs does not allow
> extensions to be enabled, and generic CPUs are already set to priv_ver
> LATEST.
>
> Signed-off-by: Daniel Henrique Barboza <dbarb...@ventanamicro.com>
> Reviewed-by: Andrew Jones <ajo...@ventanamicro.com>
Reviewed-by: Alistair Francis <alistair.fran...@wdc.com>
Alistair
> ---
> target/riscv/tcg/tcg-cpu.c | 32 ++++++++++++++++++++++++++++++++
> 1 file changed, 32 insertions(+)
>
> diff --git a/target/riscv/tcg/tcg-cpu.c b/target/riscv/tcg/tcg-cpu.c
> index 7670120673..aee98db6f8 100644
> --- a/target/riscv/tcg/tcg-cpu.c
> +++ b/target/riscv/tcg/tcg-cpu.c
> @@ -114,6 +114,26 @@ static int cpu_cfg_ext_get_min_version(uint32_t
> ext_offset)
> g_assert_not_reached();
> }
>
> +static void cpu_bump_multi_ext_priv_ver(CPURISCVState *env,
> + uint32_t ext_offset)
> +{
> + int ext_priv_ver;
> +
> + if (env->priv_ver == PRIV_VERSION_LATEST) {
> + return;
> + }
> +
> + ext_priv_ver = cpu_cfg_ext_get_min_version(ext_offset);
> +
> + if (env->priv_ver < ext_priv_ver) {
> + /*
> + * Note: the 'priv_spec' command line option, if present,
> + * will take precedence over this priv_ver bump.
> + */
> + env->priv_ver = ext_priv_ver;
> + }
> +}
> +
> static void cpu_cfg_ext_auto_update(RISCVCPU *cpu, uint32_t ext_offset,
> bool value)
> {
> @@ -757,6 +777,14 @@ static void cpu_set_misa_ext_cfg(Object *obj, Visitor
> *v, const char *name,
> return;
> }
>
> + if (misa_bit == RVH && env->priv_ver < PRIV_VERSION_1_12_0) {
> + /*
> + * Note: the 'priv_spec' command line option, if present,
> + * will take precedence over this priv_ver bump.
> + */
> + env->priv_ver = PRIV_VERSION_1_12_0;
> + }
> +
> env->misa_ext |= misa_bit;
> env->misa_ext_mask |= misa_bit;
> } else {
> @@ -886,6 +914,10 @@ static void cpu_set_multi_ext_cfg(Object *obj, Visitor
> *v, const char *name,
> return;
> }
>
> + if (value) {
> + cpu_bump_multi_ext_priv_ver(&cpu->env, multi_ext_cfg->offset);
> + }
> +
> isa_ext_update_enabled(cpu, multi_ext_cfg->offset, value);
> }
>
> --
> 2.43.0
>
>
