[Mesa-dev] [PATCH 2/2] intel: Fall back to X-tiling when larger than estimated aperture size.

[Kenneth Graunke]

If a region is larger than the estimated aperture size, we map/unmap it
by copying with the BLT engine.  Which means we can't use Y-tiling.

Fixes Piglit max-texture-size and tex3d-maxsize, which regressed in my
recent change to use Y-tiling by default on Gen6+.  This was due to a
botched merge conflict resolution.

Cc: Eric Anholt <eric at anholt.net>
Cc: Paul Berry <stereotype441 at gmail.com>
Signed-off-by: Kenneth Graunke <kenneth at whitecape.org>
---
 src/mesa/drivers/dri/intel/intel_mipmap_tree.c | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/src/mesa/drivers/dri/intel/intel_mipmap_tree.c b/src/mesa/drivers/dri/intel/intel_mipmap_tree.c
index df70cca..a985232 100644
--- a/src/mesa/drivers/dri/intel/intel_mipmap_tree.c
+++ b/src/mesa/drivers/dri/intel/intel_mipmap_tree.c
@@ -437,6 +437,25 @@ intel_miptree_create(struct intel_context *intel,
 				   total_width,
 				   total_height,
 				   expect_accelerated_upload);
+
+   /* If the region is too large to fit in the aperture, we need to use the
+    * BLT engine to support it.  The BLT paths can't currently handle Y-tiling,
+    * so we need to fall back to X.
+    */
+   if (tiling == I915_TILING_Y &&
+       mt->region->bo->size >= intel->max_gtt_map_object_size) {
+      perf_debug("%dx%d miptree larger than aperture; falling back to X-tiled\n",
+                 mt->total_width, mt->total_height);
+      intel_region_release(&mt->region);
+
+      mt->region = intel_region_alloc(intel->intelScreen,
+                                      I915_TILING_X,
+                                      mt->cpp,
+                                      total_width,
+                                      total_height,
+                                      expect_accelerated_upload);
+   }
+
    mt->offset = 0;
 
    if (!mt->region) {
-- 
1.8.2.1