[RFC PATCH 07/10] include: sbi: Add hart_suspend() platform callback

[Anup Patel]

On Wed, Feb 24, 2021 at 5:16 AM Atish Patra <atishp at atishpatra.org> wrote:
>
> On Sun, Feb 21, 2021 at 12:54 AM Anup Patel <anup.patel at wdc.com> wrote:
> >
> > We add hart_suspend() callback in platform operations which will
> > be used by HSM implementation to enter retentive or non-retentive
> > suspend state.
> >
> > Signed-off-by: Anup Patel <anup.patel at wdc.com>
> > ---
> >  include/sbi/sbi_platform.h | 30 ++++++++++++++++++++++++++++++
> >  1 file changed, 30 insertions(+)
> >
> > diff --git a/include/sbi/sbi_platform.h b/include/sbi/sbi_platform.h
> > index cc7e3ff..ede3fb3 100644
> > --- a/include/sbi/sbi_platform.h
> > +++ b/include/sbi/sbi_platform.h
> > @@ -139,6 +139,11 @@ struct sbi_platform_operations {
> >          * return if success.
> >          */
> >         int (*hart_stop)(void);
> > +       /**
> > +        * Put the current hart in platform specific suspend (or low-power)
> > +        * state.
> > +        */
> > +       int (*hart_suspend)(u32 suspend_type, ulong raddr);
> >
>
> suspend_type should be u32 or XLEN ? The spec mentioned both at
> different places.
> I noticed that it is defined as unsigned long in the next patch as well.

This applies to the reset_type parameter of sbi_system_reset() call as well.

Both suspend_type and reset_type are actually u32 so better to fix this in
spec.

>
> >         /* Check whether reset type and reason supported by the platform */
> >         int (*system_reset_check)(u32 reset_type, u32 reset_reason);
> > @@ -370,6 +375,31 @@ static inline int sbi_platform_hart_stop(const struct sbi_platform *plat)
> >         return SBI_ENOTSUPP;
> >  }
> >
> > +/**
> > + * Put the current hart in platform specific suspend (or low-power) state.
> > + *
> > + * For successful retentive suspend, the call will return 0 when the hart
> > + * resumes normal execution.
> > + *
> > + * For successful non-retentive suspend, the hart will resume from specified
> > + * resume address
> > + *
> > + * @param plat pointer to struct sbi_platform
> > + * @param suspend_type the type of suspend
> > + * @param raddr physical address where the hart can resume in M-mode after
> > + * non-retantive suspend
> > + *
> > + * @return 0 if sucessful and negative error code on failure
>
> /s/sucessful/successful

Okay, will update.

>
>
> > + */
> > +static inline int sbi_platform_hart_suspend(const struct sbi_platform *plat,
> > +                                           u32 suspend_type, ulong raddr)
> > +{
> > +       if (plat && sbi_platform_ops(plat)->hart_suspend)
> > +               return sbi_platform_ops(plat)->hart_suspend(suspend_type,
> > +                                                           raddr);
> > +       return SBI_ENOTSUPP;
> > +}
> > +
> >  /**
> >   * Early initialization for current HART
> >   *
> > --
> > 2.25.1
> >
> >
> > --
> > opensbi mailing list
> > opensbi at lists.infradead.org
> > http://lists.infradead.org/mailman/listinfo/opensbi
>
> Other than that,
>
> Reviewed-by: Atish Patra <atish.patra at wdc.com>
>
> --
> Regards,
> Atish

Thanks,
Anup