drm/i915: Refactor scratch object allocation for gen2 w/a buffer

The gen2 w/a buffer is stuffed into the same slot as the gen5+ scratch
buffer. If we pass in the size we want to allocate for the scratch
buffer, both callers can use the same routine.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1467390209-3576-11-git-send-email-chris@chris-wilson.co.uk

drivers/gpu/drm/i915/intel_lrc.c

@@ -2056,7 +2056,7 @@ static int logical_render_ring_init(struct intel_engine_cs *engine)
 	engine->emit_flush = gen8_emit_flush_render;
 	engine->emit_request = gen8_emit_request_render;
 
-	ret = intel_init_pipe_control(engine);
+	ret = intel_init_pipe_control(engine, 4096);
 	if (ret)
 		return ret;
 

drivers/gpu/drm/i915/intel_ringbuffer.c

@@ -658,16 +658,16 @@ void intel_fini_pipe_control(struct intel_engine_cs *engine)
 	engine->scratch.obj = NULL;
 }
 
-int intel_init_pipe_control(struct intel_engine_cs *engine)
+int intel_init_pipe_control(struct intel_engine_cs *engine, int size)
 {
 	struct drm_i915_gem_object *obj;
 	int ret;
 
 	WARN_ON(engine->scratch.obj);
 
-	obj = i915_gem_object_create_stolen(engine->i915->dev, 4096);
+	obj = i915_gem_object_create_stolen(engine->i915->dev, size);
 	if (!obj)
-		obj = i915_gem_object_create(engine->i915->dev, 4096);
+		obj = i915_gem_object_create(engine->i915->dev, size);
 	if (IS_ERR(obj)) {
 		DRM_ERROR("Failed to allocate scratch page\n");
 		ret = PTR_ERR(obj);
@@ -3002,7 +3002,6 @@ int intel_init_render_ring_buffer(struct drm_device *dev)
 {
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct intel_engine_cs *engine = &dev_priv->engine[RCS];
-	struct drm_i915_gem_object *obj;
 	int ret;
 
 	engine->name = "render ring";
@@ -3045,31 +3044,16 @@ int intel_init_render_ring_buffer(struct drm_device *dev)
 	engine->init_hw = init_render_ring;
 	engine->cleanup = render_ring_cleanup;
 
-	/* Workaround batchbuffer to combat CS tlb bug. */
-	if (HAS_BROKEN_CS_TLB(dev_priv)) {
-		obj = i915_gem_object_create(dev, I830_WA_SIZE);
-		if (IS_ERR(obj)) {
-			DRM_ERROR("Failed to allocate batch bo\n");
-			return PTR_ERR(obj);
-		}
-
-		ret = i915_gem_obj_ggtt_pin(obj, 0, 0);
-		if (ret != 0) {
-			drm_gem_object_unreference(&obj->base);
-			DRM_ERROR("Failed to ping batch bo\n");
-			return ret;
-		}
-
-		engine->scratch.obj = obj;
-		engine->scratch.gtt_offset = i915_gem_obj_ggtt_offset(obj);
-	}
-
 	ret = intel_init_ring_buffer(dev, engine);
 	if (ret)
 		return ret;
 
 	if (INTEL_GEN(dev_priv) >= 5) {
-		ret = intel_init_pipe_control(engine);
+		ret = intel_init_pipe_control(engine, 4096);
+		if (ret)
+			return ret;
+	} else if (HAS_BROKEN_CS_TLB(dev_priv)) {
+		ret = intel_init_pipe_control(engine, I830_WA_SIZE);
 		if (ret)
 			return ret;
 	}

drivers/gpu/drm/i915/intel_ringbuffer.h

@@ -471,8 +471,8 @@ void intel_ring_init_seqno(struct intel_engine_cs *engine, u32 seqno);
 int intel_ring_flush_all_caches(struct drm_i915_gem_request *req);
 int intel_ring_invalidate_all_caches(struct drm_i915_gem_request *req);
 
+int intel_init_pipe_control(struct intel_engine_cs *engine, int size);
 void intel_fini_pipe_control(struct intel_engine_cs *engine);
-int intel_init_pipe_control(struct intel_engine_cs *engine);
 
 int intel_init_render_ring_buffer(struct drm_device *dev);
 int intel_init_bsd_ring_buffer(struct drm_device *dev);