drm/etnaviv: allow to request specific virtual address for gem mapping

Allow the mapping code to request a specific virtual address for the gem
mapping. If the virtual address is zero we fall back to the old mode of
allocating a virtual address for the mapping.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Guido Günther <agx@sigxcpu.org>

drivers/gpu/drm/etnaviv/etnaviv_gem.c

@@ -308,7 +308,8 @@ struct etnaviv_vram_mapping *etnaviv_gem_mapping_get(
 	mapping->use = 1;
 
 	ret = etnaviv_iommu_map_gem(mmu_context, etnaviv_obj,
-				    mmu_context->global->memory_base, mapping);
+				    mmu_context->global->memory_base,
+				    mapping, 0);
 	if (ret < 0) {
 		etnaviv_iommu_context_put(mmu_context);
 		kfree(mapping);

drivers/gpu/drm/etnaviv/etnaviv_gem.h

@@ -120,7 +120,8 @@ struct page **etnaviv_gem_get_pages(struct etnaviv_gem_object *obj);
 void etnaviv_gem_put_pages(struct etnaviv_gem_object *obj);
 
 struct etnaviv_vram_mapping *etnaviv_gem_mapping_get(
-	struct drm_gem_object *obj, struct etnaviv_iommu_context *mmu_context);
+	struct drm_gem_object *obj, struct etnaviv_iommu_context *mmu_context,
+	u64 va);
 void etnaviv_gem_mapping_unreference(struct etnaviv_vram_mapping *mapping);
 
 #endif /* __ETNAVIV_GEM_H__ */

drivers/gpu/drm/etnaviv/etnaviv_mmu.c

@@ -220,9 +220,16 @@ static int etnaviv_iommu_find_iova(struct etnaviv_iommu_context *context,
 	return ret;
 }
 
+static int etnaviv_iommu_insert_exact(struct etnaviv_iommu_context *context,
+		   struct drm_mm_node *node, size_t size, u64 va)
+{
+	return drm_mm_insert_node_in_range(&context->mm, node, size, 0, 0, va,
+					   va + size, DRM_MM_INSERT_LOWEST);
+}
+
 int etnaviv_iommu_map_gem(struct etnaviv_iommu_context *context,
 	struct etnaviv_gem_object *etnaviv_obj, u32 memory_base,
-	struct etnaviv_vram_mapping *mapping)
+	struct etnaviv_vram_mapping *mapping, u64 va)
 {
 	struct sg_table *sgt = etnaviv_obj->sgt;
 	struct drm_mm_node *node;
@@ -248,7 +255,12 @@ int etnaviv_iommu_map_gem(struct etnaviv_iommu_context *context,
 
 	node = &mapping->vram_node;
 
-	ret = etnaviv_iommu_find_iova(context, node, etnaviv_obj->base.size);
+	if (va)
+		ret = etnaviv_iommu_insert_exact(context, node,
+						 etnaviv_obj->base.size, va);
+	else
+		ret = etnaviv_iommu_find_iova(context, node,
+					      etnaviv_obj->base.size);
 	if (ret < 0)
 		goto unlock;
 

drivers/gpu/drm/etnaviv/etnaviv_mmu.h

@@ -88,7 +88,7 @@ struct etnaviv_gem_object;
 
 int etnaviv_iommu_map_gem(struct etnaviv_iommu_context *context,
 	struct etnaviv_gem_object *etnaviv_obj, u32 memory_base,
-	struct etnaviv_vram_mapping *mapping);
+	struct etnaviv_vram_mapping *mapping, u64 va);
 void etnaviv_iommu_unmap_gem(struct etnaviv_iommu_context *context,
 	struct etnaviv_vram_mapping *mapping);