Re: [PATCH for-9.0 6/7] target/riscv: add RVA22S64 profile

[Andrew Jones]

On Thu, Nov 23, 2023 at 04:15:31PM -0300, Daniel Henrique Barboza wrote:
> The RVA22S64 profile consists of the following:
> 
> - all mandatory extensions of RVA22U64;
> - priv spec v1.12.0;
> - satp mode sv39;
> - Ssccptr, a cache related named feature that we're assuming always
>   enable since we don't implement a cache;
> - Other named features already implemented: Sstvecd, Sstvala,
>   Sscounterenw;
> - the new Svade named feature that was recently added.
> 
> Most of the work is already done, so this patch is enough to implement
> the profile.
> 
> After this patch, the 'rva22s64' user flag alone can be used with the
> rva64i CPU to boot Linux:
> 
> -cpu rv64i,rva22s64=true
> 
> This is the /proc/cpuinfo with this profile enabled:
> 
>  # cat /proc/cpuinfo
> processor     : 0
> hart          : 0
> isa           : 
> rv64imafdc_zicbom_zicbop_zicboz_zicntr_zicsr_zifencei_zihintpause_zihpm_zfhmin_zca_zcd_zba_zbb_zbs_zkt_svinval_svpbmt
> mmu           : sv39
> 
> Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
> ---
>  target/riscv/cpu.c | 40 ++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 40 insertions(+)
> 
> diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
> index a77118549b..d00548d164 100644
> --- a/target/riscv/cpu.c
> +++ b/target/riscv/cpu.c
> @@ -1559,8 +1559,48 @@ static RISCVCPUProfile RVA22U64 = {
>      }
>  };
>  
> +/*
> + * As with RVA22U64, RVA22S64 also defines 'named features'.
> + *
> + * Cache related features that we consider enabled since we don't
> + * implement cache: Ssccptr
> + *
> + * Other named features that we already implement: Sstvecd, Sstvala,
> + * Sscounterenw
> + *
> + * Named features that we need to enable: svade
> + *
> + * The remaining features/extensions comes from RVA22U64.
> + */
> +static RISCVCPUProfile RVA22S64 = {
> +    .name = "rva22s64",
> +    .misa_ext = RVI | RVM | RVA | RVF | RVD | RVC | RVU | RVS,
> +    .priv_spec = PRIV_VERSION_1_12_0,
> +    .satp_mode = VM_1_10_SV39,
> +    .ext_offsets = {
> +        /* rva22u64 exts and features */
> +        CPU_CFG_OFFSET(ext_zicsr), CPU_CFG_OFFSET(ext_zihintpause),
> +        CPU_CFG_OFFSET(ext_zba), CPU_CFG_OFFSET(ext_zbb),
> +        CPU_CFG_OFFSET(ext_zbs), CPU_CFG_OFFSET(ext_zfhmin),
> +        CPU_CFG_OFFSET(ext_zkt), CPU_CFG_OFFSET(ext_zicntr),
> +        CPU_CFG_OFFSET(ext_zihpm), CPU_CFG_OFFSET(ext_zicbom),
> +        CPU_CFG_OFFSET(ext_zicbop), CPU_CFG_OFFSET(ext_zicboz),
> +        CPU_CFG_OFFSET(zic64b),
> +
> +        /* rva22s64 exts */
> +        CPU_CFG_OFFSET(ext_zifencei), CPU_CFG_OFFSET(ext_svpbmt),
> +        CPU_CFG_OFFSET(ext_svinval),
> +
> +        /* rva22s64 named features */
> +        CPU_CFG_OFFSET(svade),
> +
> +        RISCV_PROFILE_EXT_LIST_END
> +    }
> +};
> +
>  RISCVCPUProfile *riscv_profiles[] = {
>      &RVA22U64,
> +    &RVA22S64,
>      NULL,
>  };
>  
> -- 
> 2.41.0
>

Since S-mode profiles will all presumably state they support everything a
U-mode profile supports too, then I wonder if we shouldn't be able to
point S-mode profiles at U-mode profiles somehow, rather than redundantly
add their extensions.

Anyway,

Reviewed-by: Andrew Jones <ajones@ventanamicro.com>

Thanks,
drew