[Mesa-dev] [PATCH v2 28/32] intel/isl: Support miptails in isl_surf_get_uncompressed_surf

[Jason Ekstrand]

---
 src/intel/isl/isl.c | 45 +++++++++++++++++++++++++++++++++++----------
 1 file changed, 35 insertions(+), 10 deletions(-)

diff --git a/src/intel/isl/isl.c b/src/intel/isl/isl.c
index 88de1407375..df4fb94a6fe 100644
--- a/src/intel/isl/isl.c
+++ b/src/intel/isl/isl.c
@@ -2657,11 +2657,22 @@ isl_surf_get_uncompressed_surf(const struct isl_device *dev,
    const uint32_t view_height_el = isl_align_div_npot(view_height_px, fmtl->bh);
 
    if (isl_tiling_is_std_y(surf->tiling)) {
-      /* Offset to the given miplevel.  Because we're using standard tilings
-       * with no miptail, arrays and 3D textures should just work so long as
-       * we have the right array stride in the end.
+      /* If the requested level is not part of the miptail, we just ofset to
+       * the requested level.  Because we're using standard tilings and aren't
+       * in the miptail, arrays and 3D textures should just work so long as we
+       * have the right array stride in the end.
+       *
+       * If the requested level is in the miptail, we instead offset to the
+       * base of the miptail.  Because offsets into the miptail are fixed by
+       * the tiling and don't depend on the actual size of the image, we can
+       * set the level in the view to offset into the miptail regardless of
+       * the fact minification yields different results for the compressed and
+       * uncompressed surface.
        */
-      isl_surf_get_image_offset_B_tile_el(surf, view->base_level, 0, 0,
+      const uint32_t base_level =
+         MIN(view->base_level, surf->miptail_start_level);
+
+      isl_surf_get_image_offset_B_tile_el(surf, base_level, 0, 0,
                                           offset_B, x_offset_el, y_offset_el);
       /* Ys and Yf should have no intratile X or Y offset */
       assert(*x_offset_el == 0 && *y_offset_el == 0);
@@ -2674,16 +2685,31 @@ isl_surf_get_uncompressed_surf(const struct isl_device *dev,
       const uint32_t view_depth_el =
          isl_align_div_npot(view_depth_px, fmtl->bd);
 
+      /* We need to compute the size of the uncompressed surface we will
+       * create.  If we're not in the miptail, it is just the view size in
+       * surface elements.  If we are in a miptail, we need a size that will
+       * minify to the view size in surface elements.  This may not be the
+       * same as the size of base_level.
+       */
+      const uint32_t ucompr_level = view->base_level - base_level;
+      struct isl_extent3d ucompr_surf_extent_el = {
+         .w = (view_width_el > 1) ? view_width_el << ucompr_level : 1,
+         .h = (view_height_el > 1) ? view_height_el << ucompr_level : 1,
+         .d = (view_depth_el > 1) ? view_depth_el << ucompr_level : 1,
+      };
+
       bool ok UNUSED;
       ok = isl_surf_init(dev, ucompr_surf,
                          .dim = surf->dim,
                          .format = view->format,
-                         .width = view_width_el,
-                         .height = view_height_el,
-                         .depth = view_depth_el,
-                         .levels = 1,
+                         .width = ucompr_surf_extent_el.width,
+                         .height = ucompr_surf_extent_el.height,
+                         .depth = ucompr_surf_extent_el.depth,
+                         .levels = view->base_level - base_level + 1,
                          .array_len = surf->logical_level0_px.array_len,
                          .samples = surf->samples,
+                         .min_miptail_start_level =
+                             surf->miptail_start_level - base_level,
                          .row_pitch_B = surf->row_pitch_B,
                          .usage = surf->usage,
                          .tiling_flags = (1u << surf->tiling));
@@ -2692,7 +2718,6 @@ isl_surf_get_uncompressed_surf(const struct isl_device *dev,
       /* Use the array pitch from the original surface.  This way 2D arrays
        * and 3D textures should work properly, just with one LOD.
        */
-      assert(ucompr_surf->array_pitch_el_rows <= array_pitch_el_rows);
       ucompr_surf->array_pitch_el_rows = array_pitch_el_rows;
 
       /* The newly created image represents only the one miplevel so we
@@ -2701,7 +2726,7 @@ isl_surf_get_uncompressed_surf(const struct isl_device *dev,
        * left alone.
        */
       *ucompr_view = *view;
-      ucompr_view->base_level = 0;
+      ucompr_view->base_level -= base_level;
    } else {
       /* For legacy tilings, we just make a new 2D surface which represents
        * the single slice of the main surface.  Due to hardware restrictions
-- 
2.19.1