intel: Fix rendering from textures after RenderTexture().

There's a serious trap for drivers: RenderTexture() does not indicate
that the texture is currently bound to the draw buffer, despite
FinishRenderTexture() signaling that the texture is just now being
unbound from the draw buffer.

We were acting as if RenderTexture() *was* the start of rendering and
that we could make texturing incoherent with the current contents of
the renderbuffer.  This caused intel oglconform sRGB
Mipmap.1D_textures to fail, because we got a call to TexImage() and
thus RenderTexture() on a texture bound to a framebuffer that wasn't
the draw buffer, so we skipped validating the new image into the
texture object used for rendering.

We can't (easily) make RenderTexture() indicate the start of drawing,
because both our driver and gallium are using it as the moment to set
up the renderbuffer wrapper used for things like MapRenderbuffer().
Instead, postpone the setup of the workaround render target miptree
until update_renderbuffer time, so that we no longer need to skip
validation of miptrees used as render targets.  As a bonus, this
should make GL_NV_texture_barrier possible.

(This also fixes a regression in the gen4 small-mipmap rendering since
3b38b33c1648b07e75dc4d8340758171e109c598, which switched
set_draw_offset from image->mt to irb->mt but didn't move the irb->mt
replacement up before set_draw_offset).

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=44961
NOTE: This is a candidate for the 8.0 branch.

5 files changed, 47 insertions, 61 deletions

diff --git a/src/mesa/drivers/dri/i965/brw_wm_surface_state.c b/src/mesa/drivers/dri/i965/brw_wm_surface_state.c
index 51d3a46245f..97ae489ea96 100644
--- a/src/mesa/drivers/dri/i965/brw_wm_surface_state.c
+++ b/src/mesa/drivers/dri/i965/brw_wm_surface_state.c
@@ -916,12 +916,48 @@ brw_update_renderbuffer_surface(struct brw_context *brw,
    struct gl_context *ctx = &intel->ctx;
    struct intel_renderbuffer *irb = intel_renderbuffer(rb);
    struct intel_mipmap_tree *mt = irb->mt;
-   struct intel_region *region = irb->mt->region;
+   struct intel_region *region;
    uint32_t *surf;
    uint32_t tile_x, tile_y;
    uint32_t format = 0;
    gl_format rb_format = intel_rb_format(irb);
 
+   if (irb->tex_image && !brw->has_surface_tile_offset) {
+      intel_renderbuffer_tile_offsets(irb, &tile_x, &tile_y);
+
+      if (tile_x != 0 || tile_y != 0) {
+	 /* Original gen4 hardware couldn't draw to a non-tile-aligned
+	  * destination in a miptree unless you actually setup your renderbuffer
+	  * as a miptree and used the fragile lod/array_index/etc. controls to
+	  * select the image.  So, instead, we just make a new single-level
+	  * miptree and render into that.
+	  */
+	 struct intel_context *intel = intel_context(ctx);
+	 struct intel_texture_image *intel_image =
+	    intel_texture_image(irb->tex_image);
+	 struct intel_mipmap_tree *new_mt;
+	 int width, height, depth;
+
+	 intel_miptree_get_dimensions_for_image(irb->tex_image, &width, &height, &depth);
+
+	 new_mt = intel_miptree_create(intel, irb->tex_image->TexObject->Target,
+				       intel_image->base.Base.TexFormat,
+				       intel_image->base.Base.Level,
+				       intel_image->base.Base.Level,
+				       width, height, depth,
+				       true);
+
+	 intel_miptree_copy_teximage(intel, intel_image, new_mt);
+	 intel_miptree_reference(&irb->mt, intel_image->mt);
+	 intel_renderbuffer_set_draw_offset(irb);
+	 intel_miptree_release(&new_mt);
+
+	 mt = irb->mt;
+      }
+   }
+
+   region = irb->mt->region;
+
    surf = brw_state_batch(brw, AUB_TRACE_SURFACE_STATE,
 			  6 * 4, 32, &brw->bind.surf_offset[unit]);
 
diff --git a/src/mesa/drivers/dri/intel/intel_fbo.c b/src/mesa/drivers/dri/intel/intel_fbo.c
index 203d512ee8e..2d1a7985602 100644
--- a/src/mesa/drivers/dri/intel/intel_fbo.c
+++ b/src/mesa/drivers/dri/intel/intel_fbo.c
@@ -553,22 +553,6 @@ intel_renderbuffer_tile_offsets(struct intel_renderbuffer *irb,
    }
 }
 
-#ifndef I915
-static bool
-need_tile_offset_workaround(struct brw_context *brw,
-			    struct intel_renderbuffer *irb)
-{
-   uint32_t tile_x, tile_y;
-
-   if (brw->has_surface_tile_offset)
-      return false;
-
-   intel_renderbuffer_tile_offsets(irb, &tile_x, &tile_y);
-
-   return tile_x != 0 || tile_y != 0;
-}
-#endif
-
 /**
  * Called by glFramebufferTexture[123]DEXT() (and other places) to
  * prepare for rendering into texture memory.  This might be called
@@ -626,42 +610,13 @@ intel_render_texture(struct gl_context * ctx,
        return;
    }
 
+   irb->tex_image = image;
+
    DBG("Begin render %s texture tex=%u w=%d h=%d refcount=%d\n",
        _mesa_get_format_name(image->TexFormat),
        att->Texture->Name, image->Width, image->Height,
        irb->Base.Base.RefCount);
 
-   intel_image->used_as_render_target = true;
-
-#ifndef I915
-   if (need_tile_offset_workaround(brw_context(ctx), irb)) {
-      /* Original gen4 hardware couldn't draw to a non-tile-aligned
-       * destination in a miptree unless you actually setup your
-       * renderbuffer as a miptree and used the fragile
-       * lod/array_index/etc. controls to select the image.  So,
-       * instead, we just make a new single-level miptree and render
-       * into that.
-       */
-      struct intel_context *intel = intel_context(ctx);
-      struct intel_mipmap_tree *new_mt;
-      int width, height, depth;
-
-      intel_miptree_get_dimensions_for_image(image, &width, &height, &depth);
-
-      new_mt = intel_miptree_create(intel, image->TexObject->Target,
-				    intel_image->base.Base.TexFormat,
-				    intel_image->base.Base.Level,
-				    intel_image->base.Base.Level,
-                                    width, height, depth,
-				    true);
-
-      intel_miptree_copy_teximage(intel, intel_image, new_mt);
-      intel_renderbuffer_set_draw_offset(irb);
-
-      intel_miptree_reference(&irb->mt, intel_image->mt);
-      intel_miptree_release(&new_mt);
-   }
-#endif
    /* update drawing region, etc */
    intel_draw_buffer(ctx);
 }
@@ -678,14 +633,13 @@ intel_finish_render_texture(struct gl_context * ctx,
    struct gl_texture_object *tex_obj = att->Texture;
    struct gl_texture_image *image =
       tex_obj->Image[att->CubeMapFace][att->TextureLevel];
-   struct intel_texture_image *intel_image = intel_texture_image(image);
+   struct intel_renderbuffer *irb = intel_renderbuffer(att->Renderbuffer);
 
    DBG("Finish render %s texture tex=%u\n",
        _mesa_get_format_name(image->TexFormat), att->Texture->Name);
 
-   /* Flag that this image may now be validated into the object's miptree. */
-   if (intel_image)
-      intel_image->used_as_render_target = false;
+   if (irb)
+      irb->tex_image = NULL;
 
    /* Since we've (probably) rendered to the texture and will (likely) use
     * it in the texture domain later on in this batchbuffer, flush the
diff --git a/src/mesa/drivers/dri/intel/intel_fbo.h b/src/mesa/drivers/dri/intel/intel_fbo.h
index a2c1b1a28dc..724f141535c 100644
--- a/src/mesa/drivers/dri/intel/intel_fbo.h
+++ b/src/mesa/drivers/dri/intel/intel_fbo.h
@@ -47,6 +47,9 @@ struct intel_renderbuffer
    struct intel_mipmap_tree *mt; /**< The renderbuffer storage. */
    drm_intel_bo *map_bo;
 
+   /* Current texture image this renderbuffer is attached to. */
+   struct gl_texture_image *tex_image;
+
    /**
     * \name Miptree view
     * \{
diff --git a/src/mesa/drivers/dri/intel/intel_tex_obj.h b/src/mesa/drivers/dri/intel/intel_tex_obj.h
index 8b278ba9875..d1a5f05f9fc 100644
--- a/src/mesa/drivers/dri/intel/intel_tex_obj.h
+++ b/src/mesa/drivers/dri/intel/intel_tex_obj.h
@@ -65,7 +65,6 @@ struct intel_texture_image
     * Else there is no image data.
     */
    struct intel_mipmap_tree *mt;
-   bool used_as_render_target;
 };
 
 static INLINE struct intel_texture_object *
diff --git a/src/mesa/drivers/dri/intel/intel_tex_validate.c b/src/mesa/drivers/dri/intel/intel_tex_validate.c
index b96f2a45291..a63068b9cff 100644
--- a/src/mesa/drivers/dri/intel/intel_tex_validate.c
+++ b/src/mesa/drivers/dri/intel/intel_tex_validate.c
@@ -97,14 +97,8 @@ intel_finalize_mipmap_tree(struct intel_context *intel, GLuint unit)
 	 /* skip too small size mipmap */
  	 if (intelImage == NULL)
 		 break;
-	 /* Need to import images in main memory or held in other trees.
-	  * If it's a render target, then its data isn't needed to be in
-	  * the object tree (otherwise we'd be FBO incomplete), and we need
-	  * to keep track of the image's MT as needing to be pulled in still,
-	  * or we'll lose the rendering that's done to it.
-          */
-         if (intelObj->mt != intelImage->mt &&
-	     !intelImage->used_as_render_target) {
+
+         if (intelObj->mt != intelImage->mt) {
             intel_miptree_copy_teximage(intel, intelImage, intelObj->mt);
          }
       }