Re: [PATCH for-9.0 v11 03/18] target/riscv/tcg: update priv_ver on user_set extensions

[Andrew Jones]

On Thu, Nov 23, 2023 at 03:51:07PM -0300, Daniel Henrique Barboza 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 <dbarboza@ventanamicro.com>
> Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
> ---
>  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..d279314624 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_validate_multi_ext_priv_ver(CPURISCVState *env,
> +                                            uint32_t ext_offset)

We should probably name this cpu_bump_multi_ext_priv_ver(). "validate"
implies we're checking something and either returning an error when it's
not what we expect or asserting on unexpected input. We do neither here,
we just bump priv_ver, when necessary.

Thanks,
drew