[Intel-gfx] [PATCH 12/18] drm/i915: Unify request submission

[Chris Wilson]

On Wed, Jul 27, 2016 at 07:09:15PM +0100, Chris Wilson wrote:
> On Wed, Jul 27, 2016 at 06:51:35PM +0100, Dave Gordon wrote:
> > >>@@ -1006,6 +1005,10 @@ int i915_guc_submission_enable(struct drm_i915_private *dev_priv)
> > >> 	host2guc_sample_forcewake(guc, client);
> > >> 	guc_init_doorbell_hw(guc);
> > >>
> > >>+	/* Take over from manual control of ELSP (execlists) */
> > >>+	for_each_engine(engine, dev_priv)
> > >>+		engine->submit_request = i915_guc_submit;
> > 
> > This doesn't get undone in i915_guc_submission_disable().
> > That will prevent the runtime fallback from working.
> 
> I honestly wasn't sure if that was supported. (runtime enabling would be
> nice...)

I've double checked. The i915_guc_submission_disable() is only called
after failing to enable the guc (in which case we haven't changed
engine->submit_request) or on calling intel_guc_fini() during
module_unload.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre