drm/i915/gt: Move engine setup out of set_default_submission

Now that we no longer switch back and forth between guc and execlists,
we no longer need to restore the backend's vfunc and can leave them set
after initialisation. The only catch is that we lose the submission on
wedging and still need to reset the submit_request vfunc on unwedging.

Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20210521183215.65451-2-matthew.brost@intel.com

drivers/gpu/drm/i915/gt/intel_execlists_submission.c

@@ -3076,29 +3076,6 @@ static void execlists_set_default_submission(struct intel_engine_cs *engine)
 	engine->submit_request = execlists_submit_request;
 	engine->schedule = i915_schedule;
 	engine->execlists.tasklet.callback = execlists_submission_tasklet;
-
-	engine->reset.prepare = execlists_reset_prepare;
-	engine->reset.rewind = execlists_reset_rewind;
-	engine->reset.cancel = execlists_reset_cancel;
-	engine->reset.finish = execlists_reset_finish;
-
-	engine->park = execlists_park;
-	engine->unpark = NULL;
-
-	engine->flags |= I915_ENGINE_SUPPORTS_STATS;
-	if (!intel_vgpu_active(engine->i915)) {
-		engine->flags |= I915_ENGINE_HAS_SEMAPHORES;
-		if (can_preempt(engine)) {
-			engine->flags |= I915_ENGINE_HAS_PREEMPTION;
-			if (IS_ACTIVE(CONFIG_DRM_I915_TIMESLICE_DURATION))
-				engine->flags |= I915_ENGINE_HAS_TIMESLICES;
-		}
-	}
-
-	if (intel_engine_has_preemption(engine))
-		engine->emit_bb_start = gen8_emit_bb_start;
-	else
-		engine->emit_bb_start = gen8_emit_bb_start_noarb;
 }
 
 static void execlists_shutdown(struct intel_engine_cs *engine)
@@ -3129,6 +3106,14 @@ logical_ring_default_vfuncs(struct intel_engine_cs *engine)
 	engine->cops = &execlists_context_ops;
 	engine->request_alloc = execlists_request_alloc;
 
+	engine->reset.prepare = execlists_reset_prepare;
+	engine->reset.rewind = execlists_reset_rewind;
+	engine->reset.cancel = execlists_reset_cancel;
+	engine->reset.finish = execlists_reset_finish;
+
+	engine->park = execlists_park;
+	engine->unpark = NULL;
+
 	engine->emit_flush = gen8_emit_flush_xcs;
 	engine->emit_init_breadcrumb = gen8_emit_init_breadcrumb;
 	engine->emit_fini_breadcrumb = gen8_emit_fini_breadcrumb_xcs;
@@ -3149,6 +3134,21 @@ logical_ring_default_vfuncs(struct intel_engine_cs *engine)
 		 * until a more refined solution exists.
 		 */
 	}
+
+	engine->flags |= I915_ENGINE_SUPPORTS_STATS;
+	if (!intel_vgpu_active(engine->i915)) {
+		engine->flags |= I915_ENGINE_HAS_SEMAPHORES;
+		if (can_preempt(engine)) {
+			engine->flags |= I915_ENGINE_HAS_PREEMPTION;
+			if (IS_ACTIVE(CONFIG_DRM_I915_TIMESLICE_DURATION))
+				engine->flags |= I915_ENGINE_HAS_TIMESLICES;
+		}
+	}
+
+	if (intel_engine_has_preemption(engine))
+		engine->emit_bb_start = gen8_emit_bb_start;
+	else
+		engine->emit_bb_start = gen8_emit_bb_start_noarb;
 }
 
 static void logical_ring_default_irqs(struct intel_engine_cs *engine)

drivers/gpu/drm/i915/gt/intel_ring_submission.c

@@ -989,14 +989,10 @@ static void gen6_bsd_submit_request(struct i915_request *request)
 static void i9xx_set_default_submission(struct intel_engine_cs *engine)
 {
 	engine->submit_request = i9xx_submit_request;
-
-	engine->park = NULL;
-	engine->unpark = NULL;
 }
 
 static void gen6_bsd_set_default_submission(struct intel_engine_cs *engine)
 {
-	i9xx_set_default_submission(engine);
 	engine->submit_request = gen6_bsd_submit_request;
 }
 

drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c

@@ -608,35 +608,6 @@ static int guc_resume(struct intel_engine_cs *engine)
 static void guc_set_default_submission(struct intel_engine_cs *engine)
 {
 	engine->submit_request = guc_submit_request;
-	engine->schedule = i915_schedule;
-	engine->execlists.tasklet.callback = guc_submission_tasklet;
-
-	engine->reset.prepare = guc_reset_prepare;
-	engine->reset.rewind = guc_reset_rewind;
-	engine->reset.cancel = guc_reset_cancel;
-	engine->reset.finish = guc_reset_finish;
-
-	engine->flags |= I915_ENGINE_NEEDS_BREADCRUMB_TASKLET;
-	engine->flags |= I915_ENGINE_HAS_PREEMPTION;
-
-	/*
-	 * TODO: GuC supports timeslicing and semaphores as well, but they're
-	 * handled by the firmware so some minor tweaks are required before
-	 * enabling.
-	 *
-	 * engine->flags |= I915_ENGINE_HAS_TIMESLICES;
-	 * engine->flags |= I915_ENGINE_HAS_SEMAPHORES;
-	 */
-
-	engine->emit_bb_start = gen8_emit_bb_start;
-
-	/*
-	 * For the breadcrumb irq to work we need the interrupts to stay
-	 * enabled. However, on all platforms on which we'll have support for
-	 * GuC submission we don't allow disabling the interrupts at runtime, so
-	 * we're always safe with the current flow.
-	 */
-	GEM_BUG_ON(engine->irq_enable || engine->irq_disable);
 }
 
 static void guc_release(struct intel_engine_cs *engine)
@@ -658,6 +629,13 @@ static void guc_default_vfuncs(struct intel_engine_cs *engine)
 	engine->cops = &guc_context_ops;
 	engine->request_alloc = guc_request_alloc;
 
+	engine->schedule = i915_schedule;
+
+	engine->reset.prepare = guc_reset_prepare;
+	engine->reset.rewind = guc_reset_rewind;
+	engine->reset.cancel = guc_reset_cancel;
+	engine->reset.finish = guc_reset_finish;
+
 	engine->emit_flush = gen8_emit_flush_xcs;
 	engine->emit_init_breadcrumb = gen8_emit_init_breadcrumb;
 	engine->emit_fini_breadcrumb = gen8_emit_fini_breadcrumb_xcs;
@@ -666,6 +644,20 @@ static void guc_default_vfuncs(struct intel_engine_cs *engine)
 		engine->emit_flush = gen12_emit_flush_xcs;
 	}
 	engine->set_default_submission = guc_set_default_submission;
+
+	engine->flags |= I915_ENGINE_NEEDS_BREADCRUMB_TASKLET;
+	engine->flags |= I915_ENGINE_HAS_PREEMPTION;
+
+	/*
+	 * TODO: GuC supports timeslicing and semaphores as well, but they're
+	 * handled by the firmware so some minor tweaks are required before
+	 * enabling.
+	 *
+	 * engine->flags |= I915_ENGINE_HAS_TIMESLICES;
+	 * engine->flags |= I915_ENGINE_HAS_SEMAPHORES;
+	 */
+
+	engine->emit_bb_start = gen8_emit_bb_start;
 }
 
 static void rcs_submission_override(struct intel_engine_cs *engine)