[PATCH 2/2] lib: sbi: add priority for reset handler

[Anup Patel]

On Fri, Oct 1, 2021 at 2:01 PM Nikita Shubin <nikita.shubin at maquefel.me> wrote:
>
> From: Nikita Shubin <n.shubin at yadro.com>
>
> Let's make system_reset_check returning priority instead of only
> true/false. In that case 0 - means not supported, and anything above
> means priority that makes existing reset handlers being used in first
> place, unless it is decided to lower their priority.
>
> The handler with the most priority wins.
>
> Signed-off-by: Nikita Shubin <n.shubin at yadro.com>
> ---
> rfc -> v0:
> - changed priority meaning to classic, the more the more prioritized
> - moved all checks to sbi_system_reset
> ---
>  lib/sbi/sbi_system.c | 23 +++++++++++++++++------
>  1 file changed, 17 insertions(+), 6 deletions(-)
>
> diff --git a/lib/sbi/sbi_system.c b/lib/sbi/sbi_system.c
> index 6e6bb80..177f130 100644
> --- a/lib/sbi/sbi_system.c
> +++ b/lib/sbi/sbi_system.c
> @@ -22,18 +22,29 @@ static SBI_LIST_HEAD(reset_devices_list);
>
>  const struct sbi_system_reset_device *sbi_system_reset_get_device(u32 reset_type, u32 reset_reason)
>  {
> -       struct sbi_system_reset_device *dev = 0;
> +       struct sbi_system_reset_device *reset_dev = 0;

Better assign NULL here since this is a pointer.

>         struct sbi_dlist *pos;
> +       /** lowest priority - any non zero is our candidate */
> +       int priority = 0;
>
>         /* Check each reset device registered for supported reset type */
>         sbi_list_for_each(pos, &(reset_devices_list)) {
> -               dev = to_system_reset_device(pos);
> -               if (dev->system_reset_check &&
> -                       dev->system_reset_check(reset_type, reset_reason))
> -                       break;
> +               struct sbi_system_reset_device *dev =
> +                       to_system_reset_device(pos);
> +               if (dev->system_reset_check) {
> +                       int status = dev->system_reset_check(reset_type, reset_reason);
> +                       /** reset_type not supported */
> +                       if (status == 0)
> +                               continue;
> +
> +                       if (status > priority) {
> +                               reset_dev = dev;
> +                               priority = status;
> +                       }
> +               }
>         }
>
> -       return dev;
> +       return reset_dev;
>  }
>
>  void sbi_system_reset_add_device(struct sbi_system_reset_device *dev)
> --
> 2.31.1
>
>
> --
> opensbi mailing list
> opensbi at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/opensbi

Apart from the minor comment above, it looks good to me.

Reviewed-by: Anup Patel <anup.patel at wdc.com>

Regards,
Anup