[PATCH 11/11] lib: sbi_platform: Add callback to populate HART extensions

[Anup Patel]

On Wed, May 4, 2022 at 7:36 AM Atish Patra <atishp at atishpatra.org> wrote:
>
> On Fri, Apr 29, 2022 at 8:52 AM Anup Patel <apatel at ventanamicro.com> wrote:
> >
> > We add platform specific extensions_init() callback which allows
> > platforms to populate HART extensions for each HART. For example,
> > the generic platform can populate HART extensions from HART ISA
> > string described in DeviceTree.
> >
> > Signed-off-by: Anup Patel <apatel at ventanamicro.com>
> > ---
> >  include/sbi/sbi_platform.h | 18 ++++++++++++++++++
> >  lib/sbi/sbi_hart.c         | 18 ++++++++++++++----
> >  2 files changed, 32 insertions(+), 4 deletions(-)
> >
> > diff --git a/include/sbi/sbi_platform.h b/include/sbi/sbi_platform.h
> > index 2c777ac..87024db 100644
> > --- a/include/sbi/sbi_platform.h
> > +++ b/include/sbi/sbi_platform.h
> > @@ -89,6 +89,9 @@ struct sbi_platform_operations {
> >          */
> >         int (*misa_get_xlen)(void);
> >
> > +       /** Initialize (or populate) HART extensions for the platform */
> > +       int (*extensions_init)(void);
> > +
>
>
> >         /** Initialize (or populate) domains for the platform */
> >         int (*domains_init)(void);
> >
> > @@ -453,6 +456,21 @@ static inline int sbi_platform_misa_xlen(const struct sbi_platform *plat)
> >         return -1;
> >  }
> >
> > +/**
> > + * Initialize (or populate) HART extensions for the platform
> > + *
> > + * @param plat pointer to struct sbi_platform
> > + *
> > + * @return 0 on success and negative error code on failure
> > + */
> > +static inline int sbi_platform_extensions_init(
> > +                                       const struct sbi_platform *plat)
> > +{
> > +       if (plat && sbi_platform_ops(plat)->extensions_init)
> > +               return sbi_platform_ops(plat)->extensions_init();
> > +       return 0;
> > +}
> > +
>
>
>
> >  /**
> >   * Initialize (or populate) domains for the platform
> >   *
> > diff --git a/lib/sbi/sbi_hart.c b/lib/sbi/sbi_hart.c
> > index 3fc8899..8284792 100644
> > --- a/lib/sbi/sbi_hart.c
> > +++ b/lib/sbi/sbi_hart.c
> > @@ -536,16 +536,17 @@ static int hart_pmu_get_allowed_bits(void)
> >         return num_bits;
> >  }
> >
> > -static void hart_detect_features(struct sbi_scratch *scratch)
> > +static int hart_detect_features(struct sbi_scratch *scratch)
> >  {
> >         struct sbi_trap_info trap = {0};
> >         struct hart_features *hfeatures =
> >                 sbi_scratch_offset_ptr(scratch, hart_features_offset);
> >         unsigned long val, oldval;
> > +       int rc;
> >
> >         /* If hart features already detected then do nothing */
> >         if (hfeatures->detected)
> > -               return;
> > +               return 0;
> >
> >         /* Clear hart features */
> >         hfeatures->extensions = 0;
> > @@ -680,10 +681,15 @@ __mhpm_skip:
> >                                         SBI_HART_EXT_SMSTATEEN, true);
> >         }
> >
> > +       /* Let platform populate extensions */
> > +       rc = sbi_platform_extensions_init(sbi_platform_thishart_ptr());
> > +       if (rc)
> > +               return rc;
> > +
> >         /* Mark hart feature detection done */
> >         hfeatures->detected = true;
> >
> > -       return;
> > +       return 0;
> >  }
> >
> >  int sbi_hart_reinit(struct sbi_scratch *scratch)
> > @@ -705,6 +711,8 @@ int sbi_hart_reinit(struct sbi_scratch *scratch)
> >
> >  int sbi_hart_init(struct sbi_scratch *scratch, bool cold_boot)
> >  {
> > +       int rc;
> > +
> >         if (cold_boot) {
> >                 if (misa_extension('H'))
> >                         sbi_hart_expected_trap = &__sbi_expected_trap_hext;
> > @@ -715,7 +723,9 @@ int sbi_hart_init(struct sbi_scratch *scratch, bool cold_boot)
> >                         return SBI_ENOMEM;
> >         }
> >
> > -       hart_detect_features(scratch);
> > +       rc = hart_detect_features(scratch);
> > +       if (rc)
> > +               return rc;
> >
> >         return sbi_hart_reinit(scratch);
> >  }
> > --
> > 2.34.1
> >
>
>
> Reviewed-by: Atish Patra <atishp at rivosinc.com>

Applied this patch to the riscv/opensbi repo

Regards,
Anup

> --
> Regards,
> Atish