drm/i915: split out dma mapping from global gtt bind/unbind functions

Note that there's a functional change buried in this patch wrt the ilk
dmar workaround: We now only idle the gpu while tearing down the dmar
mappings, not while clearing the gtt. Keeping the current semantics
would have made for some really ugly code and afaik the issue is only
with the dmar unmapping that needs a fully idle gpu.

Reviewed-and-tested-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_drv.h

@@ -1291,10 +1291,11 @@ void i915_ppgtt_unbind_object(struct i915_hw_ppgtt *ppgtt,
 			      struct drm_i915_gem_object *obj);
 
 void i915_gem_restore_gtt_mappings(struct drm_device *dev);
-int __must_check i915_gem_gtt_bind_object(struct drm_i915_gem_object *obj);
-void i915_gem_gtt_rebind_object(struct drm_i915_gem_object *obj,
+int __must_check i915_gem_gtt_prepare_object(struct drm_i915_gem_object *obj);
+void i915_gem_gtt_bind_object(struct drm_i915_gem_object *obj,
 				enum i915_cache_level cache_level);
 void i915_gem_gtt_unbind_object(struct drm_i915_gem_object *obj);
+void i915_gem_gtt_finish_object(struct drm_i915_gem_object *obj);
 
 /* i915_gem_evict.c */
 int __must_check i915_gem_evict_something(struct drm_device *dev, int min_size,

drivers/gpu/drm/i915/i915_gem.c

@@ -2102,6 +2102,7 @@ i915_gem_object_unbind(struct drm_i915_gem_object *obj)
 		i915_ppgtt_unbind_object(dev_priv->mm.aliasing_ppgtt, obj);
 		obj->has_aliasing_ppgtt_mapping = 0;
 	}
+	i915_gem_gtt_finish_object(obj);
 
 	i915_gem_object_put_pages_gtt(obj);
 
@@ -2746,7 +2747,7 @@ i915_gem_object_bind_to_gtt(struct drm_i915_gem_object *obj,
 		return ret;
 	}
 
-	ret = i915_gem_gtt_bind_object(obj);
+	ret = i915_gem_gtt_prepare_object(obj);
 	if (ret) {
 		i915_gem_object_put_pages_gtt(obj);
 		drm_mm_put_block(obj->gtt_space);
@@ -2757,6 +2758,7 @@ i915_gem_object_bind_to_gtt(struct drm_i915_gem_object *obj,
 
 		goto search_free;
 	}
+	i915_gem_gtt_bind_object(obj, obj->cache_level);
 
 	list_add_tail(&obj->gtt_list, &dev_priv->mm.gtt_list);
 	list_add_tail(&obj->mm_list, &dev_priv->mm.inactive_list);
@@ -2950,7 +2952,7 @@ int i915_gem_object_set_cache_level(struct drm_i915_gem_object *obj,
 				return ret;
 		}
 
-		i915_gem_gtt_rebind_object(obj, cache_level);
+		i915_gem_gtt_bind_object(obj, cache_level);
 		if (obj->has_aliasing_ppgtt_mapping)
 			i915_ppgtt_bind_object(dev_priv->mm.aliasing_ppgtt,
 					       obj, cache_level);

drivers/gpu/drm/i915/i915_gem_gtt.c

@@ -355,42 +355,28 @@ void i915_gem_restore_gtt_mappings(struct drm_device *dev)
 
 	list_for_each_entry(obj, &dev_priv->mm.gtt_list, gtt_list) {
 		i915_gem_clflush_object(obj);
-		i915_gem_gtt_rebind_object(obj, obj->cache_level);
+		i915_gem_gtt_bind_object(obj, obj->cache_level);
 	}
 
 	intel_gtt_chipset_flush();
 }
 
-int i915_gem_gtt_bind_object(struct drm_i915_gem_object *obj)
+int i915_gem_gtt_prepare_object(struct drm_i915_gem_object *obj)
 {
 	struct drm_device *dev = obj->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
-	unsigned int agp_type = cache_level_to_agp_type(dev, obj->cache_level);
-	int ret;
 
-	if (dev_priv->mm.gtt->needs_dmar) {
-		ret = intel_gtt_map_memory(obj->pages,
-					   obj->base.size >> PAGE_SHIFT,
-					   &obj->sg_list,
-					   &obj->num_sg);
-		if (ret != 0)
-			return ret;
-
-		intel_gtt_insert_sg_entries(obj->sg_list,
-					    obj->num_sg,
-					    obj->gtt_space->start >> PAGE_SHIFT,
-					    agp_type);
-	} else
-		intel_gtt_insert_pages(obj->gtt_space->start >> PAGE_SHIFT,
-				       obj->base.size >> PAGE_SHIFT,
-				       obj->pages,
-				       agp_type);
-
-	return 0;
+	if (dev_priv->mm.gtt->needs_dmar)
+		return intel_gtt_map_memory(obj->pages,
+					    obj->base.size >> PAGE_SHIFT,
+					    &obj->sg_list,
+					    &obj->num_sg);
+	else
+		return 0;
 }
 
-void i915_gem_gtt_rebind_object(struct drm_i915_gem_object *obj,
-				enum i915_cache_level cache_level)
+void i915_gem_gtt_bind_object(struct drm_i915_gem_object *obj,
+			      enum i915_cache_level cache_level)
 {
 	struct drm_device *dev = obj->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
@@ -411,6 +397,12 @@ void i915_gem_gtt_rebind_object(struct drm_i915_gem_object *obj,
 }
 
 void i915_gem_gtt_unbind_object(struct drm_i915_gem_object *obj)
+{
+	intel_gtt_clear_range(obj->gtt_space->start >> PAGE_SHIFT,
+			      obj->base.size >> PAGE_SHIFT);
+}
+
+void i915_gem_gtt_finish_object(struct drm_i915_gem_object *obj)
 {
 	struct drm_device *dev = obj->base.dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
@@ -418,9 +410,6 @@ void i915_gem_gtt_unbind_object(struct drm_i915_gem_object *obj)
 
 	interruptible = do_idling(dev_priv);
 
-	intel_gtt_clear_range(obj->gtt_space->start >> PAGE_SHIFT,
-			      obj->base.size >> PAGE_SHIFT);
-
 	if (obj->sg_list) {
 		intel_gtt_unmap_memory(obj->sg_list, obj->num_sg);
 		obj->sg_list = NULL;