Re: [PATCH v2 2/4] target/riscv: use RVB in RVA22U64

[Andrew Jones]

On Tue, Jan 14, 2025 at 03:59:59PM -0300, Daniel Henrique Barboza wrote:
> From the time we added RVA22U64 until now the spec didn't declare 'RVB'
> as a dependency, using zba/zbb/zbs instead. Since then the RVA22 spec
> [1] added the following in the 'RVA22U64 Mandatory Extensions' section:
> 
> "B Bit-manipulation instructions
> 
> Note: The B extension comprises the Zba, Zbb, and Zbs extensions. At the
> time of RVA22U64's ratification, the B extension had not yet been
> defined, and so RVA22U64 explicitly mandated Zba, Zbb, and Zbs instead.
> Mandating B is equivalent."
> 
> It is also equivalent to QEMU (see riscv_cpu_validate_b() in
> target/riscv/tcg/tcg-cpu.c).
> 
> Finally, RVA23U64 [2] directly mentions RVB as a mandatory extension,
> not citing zba/zbb/zbs.
> 
> To make it clear that RVA23U64 will extend RVA22U64 (i.e. RVA22 is a
> parent of RVA23), use RVB in RVA22U64 as well.
> 
> (bios-tables-test change: RVB added to riscv,isa)
> 
> [1] 
> https://github.com/riscv/riscv-profiles/blob/main/src/profiles.adoc#61-rva22u64-profile
> [2] 
> https://github.com/riscv/riscv-profiles/blob/main/src/rva23-profile.adoc#rva23u64-profile
> 
> Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
> ---
>  target/riscv/cpu.c                |   2 +-
>  tests/data/acpi/riscv64/virt/RHCT | Bin 398 -> 400 bytes
>  2 files changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c
> index b187ef2e4b..6fb4d5f374 100644
> --- a/target/riscv/cpu.c
> +++ b/target/riscv/cpu.c
> @@ -2351,7 +2351,7 @@ static const PropertyInfo prop_marchid = {
>  static RISCVCPUProfile RVA22U64 = {
>      .parent = NULL,
>      .name = "rva22u64",
> -    .misa_ext = RVI | RVM | RVA | RVF | RVD | RVC | RVU,
> +    .misa_ext = RVI | RVM | RVA | RVF | RVD | RVC | RVB | RVU,
>      .priv_spec = RISCV_PROFILE_ATTR_UNUSED,
>      .satp_mode = RISCV_PROFILE_ATTR_UNUSED,
>      .ext_offsets = {
> diff --git a/tests/data/acpi/riscv64/virt/RHCT 
> b/tests/data/acpi/riscv64/virt/RHCT
> index 
> b14ec15e553200760a63aad65586913d31ea2edc..13c8025b868051485be5ba62974a22971a07bc6a
>  100644
> GIT binary patch
> delta 53
> zcmeBUp1{l%<l!7LfsuiM@#{n`13^7TMg~>JqB1j+%-qDZl;ot1UQ&#clNpsc(ij;S
> I3K$s}0ARKZK>z>%
> 
> delta 52
> zcmbQh+{ern<l!9B$H>6Im@tvcKtP9)kwJyAsLaeHGdD3UC3&N_6yxMHMkS6EMh1pF
> HMg|4|IwT82
> 
> -- 
> 2.47.1
>

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