i965: Implement SetTextureStorageForBufferObject

Reviewed-by: Neil Roberts <neil@linux.intel.com>

src/mesa/drivers/dri/i965/intel_tex.c

@@ -5,6 +5,7 @@
 #include "main/mipmap.h"
 #include "drivers/common/meta.h"
 #include "brw_context.h"
+#include "intel_buffer_objects.h"
 #include "intel_mipmap_tree.h"
 #include "intel_tex.h"
 #include "intel_fbo.h"
@@ -298,6 +299,60 @@ intel_texture_view(struct gl_context *ctx,
    return GL_TRUE;
 }
 
+static bool
+intel_set_texture_storage_for_buffer_object(struct gl_context *ctx,
+                                            struct gl_texture_object *tex_obj,
+                                            struct gl_buffer_object *buffer_obj,
+                                            uint32_t buffer_offset,
+                                            uint32_t row_stride,
+                                            bool read_only)
+{
+   struct brw_context *brw = brw_context(ctx);
+   struct intel_texture_object *intel_texobj = intel_texture_object(tex_obj);
+   struct gl_texture_image *image = tex_obj->Image[0][0];
+   struct intel_texture_image *intel_image = intel_texture_image(image);
+   struct intel_buffer_object *intel_buffer_obj = intel_buffer_object(buffer_obj);
+
+   if (!read_only) {
+      /* Renderbuffers have the restriction that the buffer offset and
+       * surface pitch must be a multiple of the element size.  If it's
+       * not, we have to fail and fall back to software.
+       */
+      int cpp = _mesa_get_format_bytes(image->TexFormat);
+      if (buffer_offset % cpp || row_stride % cpp) {
+         perf_debug("Bad PBO alignment; fallback to CPU mapping\n");
+         return false;
+      }
+   }
+
+   assert(intel_texobj->mt == NULL);
+
+   drm_intel_bo *bo = intel_bufferobj_buffer(brw, intel_buffer_obj,
+                                             buffer_offset,
+                                             row_stride * image->Height);
+   intel_texobj->mt =
+      intel_miptree_create_for_bo(brw, bo,
+                                  image->TexFormat,
+                                  buffer_offset,
+                                  image->Width, image->Height, image->Depth,
+                                  row_stride);
+   if (!intel_texobj->mt)
+      return false;
+
+   if (!_swrast_init_texture_image(image))
+      return false;
+
+   intel_miptree_reference(&intel_image->mt, intel_texobj->mt);
+
+   /* The miptree is in a validated state, so no need to check later. */
+   intel_texobj->needs_validate = false;
+   intel_texobj->validated_first_level = 0;
+   intel_texobj->validated_last_level = 0;
+   intel_texobj->_Format = intel_texobj->mt->format;
+
+   return true;
+}
+
 void
 intelInitTextureFuncs(struct dd_function_table *functions)
 {
@@ -311,4 +366,6 @@ intelInitTextureFuncs(struct dd_function_table *functions)
    functions->MapTextureImage = intel_map_texture_image;
    functions->UnmapTextureImage = intel_unmap_texture_image;
    functions->TextureView = intel_texture_view;
+   functions->SetTextureStorageForBufferObject =
+      intel_set_texture_storage_for_buffer_object;
 }