[PATCH 1/3] lib: sbi: sse: Return a value from the register callback

[Atish Kumar Patra]

On Fri, Dec 6, 2024 at 1:00 PM Clément Léger <cleger at rivosinc.com> wrote:
>
> Some events might not be available to registration due to missing
> dependencies (ISA extensions for instance). Return an 'int' from the
> register_cb() callback so that this can be handled.
>
> Signed-off-by: Clément Léger <cleger at rivosinc.com>
> ---
>  include/sbi/sbi_sse.h |  2 +-
>  lib/sbi/sbi_sse.c     | 16 ++++++++++++++--
>  2 files changed, 15 insertions(+), 3 deletions(-)
>
> diff --git a/include/sbi/sbi_sse.h b/include/sbi/sbi_sse.h
> index 7419698a..58bd2ae0 100644
> --- a/include/sbi/sbi_sse.h
> +++ b/include/sbi/sbi_sse.h
> @@ -36,7 +36,7 @@ struct sbi_sse_cb_ops {
>         /**
>          * Called when the SBI_EXT_SSE_REGISTER is invoked on the event.
>          */
> -       void (*register_cb)(uint32_t event_id);
> +       int (*register_cb)(uint32_t event_id);
>
>         /**
>          * Called when the SBI_EXT_SSE_UNREGISTER is invoked on the event.
> diff --git a/lib/sbi/sbi_sse.c b/lib/sbi/sbi_sse.c
> index bf5620e8..5679c26f 100644
> --- a/lib/sbi/sbi_sse.c
> +++ b/lib/sbi/sbi_sse.c
> @@ -50,6 +50,15 @@ static const uint32_t supported_events[] = {
>
>  #define EVENT_COUNT array_size(supported_events)
>
> +#define sse_event_invoke_cb_ret(_event, _cb, ...)                             \
> +       ({                                                                    \
> +               int __ret = 0;                                                \
> +               if (_event->cb_ops && _event->cb_ops->_cb)                    \
> +                       __ret = _event->cb_ops->_cb(_event->event_id,         \
> +                                                  ##__VA_ARGS__);            \
> +               __ret;                                                        \
> +       })
> +
>  #define sse_event_invoke_cb(_event, _cb, ...)                                 \
>         {                                                                     \
>                 if (_event->cb_ops && _event->cb_ops->_cb)                    \
> @@ -423,16 +432,19 @@ static int sse_event_register(struct sbi_sse_event *e,
>                               unsigned long handler_entry_pc,
>                               unsigned long handler_entry_arg)
>  {
> +       int ret;
>         if (sse_event_state(e) != SBI_SSE_STATE_UNUSED)
>                 return SBI_EINVALID_STATE;
>
> +       ret = sse_event_invoke_cb_ret(e, register_cb);
> +       if (ret)
> +               return ret;
> +
>         e->attrs.entry.pc = handler_entry_pc;
>         e->attrs.entry.arg = handler_entry_arg;
>
>         sse_event_set_state(e, SBI_SSE_STATE_REGISTERED);
>
> -       sse_event_invoke_cb(e, register_cb);
> -
>         return 0;
>  }
>

Reviewed-by: Atish Patra <atishp at rivosinc.com>

> --
> 2.45.2
>