Re: [REVIEW ONLY 1/1] UNRATIFIED RISC-V: Add 'Svadu' extension

[Palmer Dabbelt <palmer@dabbelt.com>]

On Mon, 28 Nov 2022 17:18:15 PST (-0800), binutils@sourceware.org wrote:
> From: Tsukasa OI <research_trasio@irq.a4lg.com>
>
> [DO NOT MERGE]
> Until 'Svadu' extension is frozen/ratified and final version number is
> determined, this patch should not be merged upstream.  This commit uses
> unratified version 0.1 as in the documentation (instead of possible 1.0
> after ratification).
>
> This commit implements support for 'Svadu' extension.  Because it does not
> add any instructions or CSRs (but adds bits to existing CSRs), this commit
> adds extension name support and implication to the 'Zicsr' extension.
>
> This is based on "Hardware Updating of PTE A/D Bits (Svadu)" version 0.1,
> stable <https://github.com/riscv/riscv-svadu/releases/tag/vv0.1>.
>
> bfd/ChangeLog:
>
> 	* elfxx-riscv.c (riscv_implicit_subsets): Add implication from
> 	'Svadu' to 'Zicsr'.  (riscv_supported_std_s_ext) Add 'Svadu'.
> ---
>  bfd/elfxx-riscv.c | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/bfd/elfxx-riscv.c b/bfd/elfxx-riscv.c
> index 0bcf2fdcfa34..826f248f88c4 100644
> --- a/bfd/elfxx-riscv.c
> +++ b/bfd/elfxx-riscv.c
> @@ -1108,6 +1108,7 @@ static struct riscv_implicit_subset riscv_implicit_subsets[] =
>    {"sscofpmf", "zicsr",		check_implicit_always},
>    {"ssstateen", "zicsr",	check_implicit_always},
>    {"sstc", "zicsr",		check_implicit_always},
> +  {"svadu", "zicsr",		check_implicit_always},
>    {NULL, NULL, NULL}
>  };
>
> @@ -1230,6 +1231,7 @@ static struct riscv_supported_ext riscv_supported_std_s_ext[] =
>    {"sscofpmf",		ISA_SPEC_CLASS_DRAFT,		1, 0, 0 },
>    {"ssstateen",		ISA_SPEC_CLASS_DRAFT,		1, 0, 0 },
>    {"sstc",		ISA_SPEC_CLASS_DRAFT,		1, 0, 0 },
> +  {"svadu",		ISA_SPEC_CLASS_DRAFT,		0, 1, 0 },
>    {"svinval",		ISA_SPEC_CLASS_DRAFT,		1, 0, 0 },
>    {"svnapot",		ISA_SPEC_CLASS_DRAFT,		1, 0, 0 },
>    {"svpbmt",		ISA_SPEC_CLASS_DRAFT,		1, 0, 0 },

Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com> # pending freeze