[v1, 4/6] riscv: cpufeature: add zve32[xf] and zve64[xfd] isa detection

[Andy Chiu]

On Tue, Mar 12, 2024 at 8:51 PM Clément Léger <cleger at rivosinc.com> wrote:
>
>
>
> On 12/03/2024 13:36, Andy Chiu wrote:
> > Multiple Vector subextensions are added. Also, the patch takes care of
> > the dependencies of Vector subextensions by macro expansions. So, if
> > some "embedded" platform only reports "zve64f" on the ISA string, the
> > parser is able to expand it to zve32x zve32f zve64x and zve64f.
> >
> > Signed-off-by: Andy Chiu <andy.chiu at sifive.com>
> > ---
> >  arch/riscv/include/asm/hwcap.h |  5 +++++
> >  arch/riscv/kernel/cpufeature.c | 41 +++++++++++++++++++++++++++++++++-
> >  2 files changed, 45 insertions(+), 1 deletion(-)
> >
> > diff --git a/arch/riscv/include/asm/hwcap.h b/arch/riscv/include/asm/hwcap.h
> > index 5340f818746b..24efea44f1ab 100644
> > --- a/arch/riscv/include/asm/hwcap.h
> > +++ b/arch/riscv/include/asm/hwcap.h
> > @@ -80,6 +80,11 @@
> >  #define RISCV_ISA_EXT_ZFA            71
> >  #define RISCV_ISA_EXT_ZTSO           72
> >  #define RISCV_ISA_EXT_ZACAS          73
> > +#define RISCV_ISA_EXT_ZVE32X         74
> > +#define RISCV_ISA_EXT_ZVE32F         75
> > +#define RISCV_ISA_EXT_ZVE64X         76
> > +#define RISCV_ISA_EXT_ZVE64F         77
> > +#define RISCV_ISA_EXT_ZVE64D         78
> >
> >  #define RISCV_ISA_EXT_MAX            128
> >  #define RISCV_ISA_EXT_INVALID                U32_MAX
> > diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
> > index 8986ceb58188..3aa0df3f3b41 100644
> > --- a/arch/riscv/kernel/cpufeature.c
> > +++ b/arch/riscv/kernel/cpufeature.c
> > @@ -201,6 +201,40 @@ static const unsigned int riscv_zvbb_exts[] = {
> >       RISCV_ISA_EXT_ZVKB
> >  };
> >
> > +#define RISCV_ISA_EXT_ZVE32F_IMPLY_LIST      \
> > +     RISCV_ISA_EXT_ZVE32F,           \
> > +     RISCV_ISA_EXT_ZVE32X,
> > +
> > +#define RISCV_ISA_EXT_ZVE64F_IMPLY_LIST      \
> > +     RISCV_ISA_EXT_ZVE64F,           \
> > +     RISCV_ISA_EXT_ZVE64X,           \
> > +     RISCV_ISA_EXT_ZVE32F_IMPLY_LIST
> > +
> > +#define RISCV_ISA_EXT_ZVE64D_IMPLY_LIST      \
> > +     RISCV_ISA_EXT_ZVE64D,           \
> > +     RISCV_ISA_EXT_ZVE64F_IMPLY_LIST
> > +
> > +static const unsigned int riscv_zve32f_exts[] = {
> > +     RISCV_ISA_EXT_ZVE32F_IMPLY_LIST
> > +};
> > +
> > +static const unsigned int riscv_zve64f_exts[] = {
> > +     RISCV_ISA_EXT_ZVE64F_IMPLY_LIST
> > +};
> > +
> > +static const unsigned int riscv_zve64d_exts[] = {
> > +     RISCV_ISA_EXT_ZVE64D_IMPLY_LIST
> > +};
> > +
> > +static const unsigned int riscv_zve64x_exts[] = {
> > +     RISCV_ISA_EXT_ZVE32X,
> > +     RISCV_ISA_EXT_ZVE64X
> > +};
> > +
> > +static const unsigned int riscv_v_exts[] = {
> > +     RISCV_ISA_EXT_ZVE64D_IMPLY_LIST
> > +};
> > +
> >  /*
> >   * The canonical order of ISA extension names in the ISA string is defined in
> >   * chapter 27 of the unprivileged specification.
> > @@ -248,7 +282,7 @@ const struct riscv_isa_ext_data riscv_isa_ext[] = {
> >       __RISCV_ISA_EXT_DATA(d, RISCV_ISA_EXT_d),
> >       __RISCV_ISA_EXT_DATA(q, RISCV_ISA_EXT_q),
> >       __RISCV_ISA_EXT_DATA(c, RISCV_ISA_EXT_c),
> > -     __RISCV_ISA_EXT_DATA(v, RISCV_ISA_EXT_v),
> > +     __RISCV_ISA_EXT_SUPERSET(v, RISCV_ISA_EXT_v, riscv_v_exts),
> >       __RISCV_ISA_EXT_DATA(h, RISCV_ISA_EXT_h),
> >       __RISCV_ISA_EXT_DATA(zicbom, RISCV_ISA_EXT_ZICBOM),
> >       __RISCV_ISA_EXT_DATA(zicboz, RISCV_ISA_EXT_ZICBOZ),
> > @@ -283,6 +317,11 @@ const struct riscv_isa_ext_data riscv_isa_ext[] = {
> >       __RISCV_ISA_EXT_DATA(ztso, RISCV_ISA_EXT_ZTSO),
> >       __RISCV_ISA_EXT_SUPERSET(zvbb, RISCV_ISA_EXT_ZVBB, riscv_zvbb_exts),
> >       __RISCV_ISA_EXT_DATA(zvbc, RISCV_ISA_EXT_ZVBC),
> > +     __RISCV_ISA_EXT_SUPERSET(zve32f, RISCV_ISA_EXT_ZVE32F, riscv_zve32f_exts),
>
> Hi Andy,
>
> Nit: Since RISCV_ISA_EXT_ZVE32F is already used here as .id, you don't
> need to insert it in the riscv_zve32f_exts array. It won't hurt but the
> existing extensions that uses the __RISCV_ISA_EXT_SUPERSET() macro don't
> do that.
>

Noted, I will update it in the next revision.

Thanks,
Andy

> > +     __RISCV_ISA_EXT_DATA(zve32x, RISCV_ISA_EXT_ZVE32X),
> > +     __RISCV_ISA_EXT_SUPERSET(zve64f, RISCV_ISA_EXT_ZVE64F, riscv_zve64f_exts),
> > +     __RISCV_ISA_EXT_SUPERSET(zve64d, RISCV_ISA_EXT_ZVE64D, riscv_zve64d_exts),
> > +     __RISCV_ISA_EXT_SUPERSET(zve64x, RISCV_ISA_EXT_ZVE64X, riscv_zve64x_exts),
>
> Ditto for the last 3 __RISCV_ISA_EXT_SUPERSET().
>
> Apart from that, it looks good !
>
> Thanks,
>
> Clément
>
> >       __RISCV_ISA_EXT_DATA(zvfh, RISCV_ISA_EXT_ZVFH),
> >       __RISCV_ISA_EXT_DATA(zvfhmin, RISCV_ISA_EXT_ZVFHMIN),
> >       __RISCV_ISA_EXT_DATA(zvkb, RISCV_ISA_EXT_ZVKB),