[Intel-gfx] [PATCH 3/5] drm/i915/guc: Simplify GuC doorbell logic

[Chris Wilson]

Quoting Michał Winiarski (2017-09-12 18:40:54)
> -static int guc_ring_doorbell(struct i915_guc_client *client)
> +static void guc_ring_doorbell(struct i915_guc_client *client)
>  {
> -       struct guc_process_desc *desc = __get_process_desc(client);
> -       union guc_doorbell_qw db_cmp, db_exc, db_ret;
> -       union guc_doorbell_qw *db;
> -       int attempt = 2, ret = -EAGAIN;
> -
> -       /* Update the tail so it is visible to GuC */
> -       desc->tail = client->wq_tail;

At this point in the series, guc_ring_doorbell() is still responsible
for the desc->tail update.

Hmm. Twice now that kbl has behaved unexpectedly. Do you have one to
hand?
-Chris