[Mesa-dev] [PATCH 06/11] intel/isl: Add some sanity checks for compressed surfaces

[Jason Ekstrand]

---
 src/intel/isl/isl_surface_state.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/src/intel/isl/isl_surface_state.c b/src/intel/isl/isl_surface_state.c
index 1620c93..e8bdb65 100644
--- a/src/intel/isl/isl_surface_state.c
+++ b/src/intel/isl/isl_surface_state.c
@@ -254,6 +254,24 @@ isl_genX(surf_fill_state_s)(const struct isl_device *dev, void *state,
    if (info->surf->dim == ISL_SURF_DIM_1D)
       assert(!isl_format_is_compressed(info->view->format));
 
+   if (isl_format_is_compressed(info->surf->format)) {
+      /* You're not allowed to make a view of a compressed format with any
+       * format other than the surface format.  None of the userspace APIs
+       * allow for this directly and doing so would mess up a number of
+       * surface parameters such as Width, Height, and alignments.  Ideally,
+       * we'd like to assert that the two formats match.  However, we have an
+       * S3TC workaround that requires us to do reinterpretation.  So assert
+       * that they're at least the same bpb and block size.
+       */
+      MAYBE_UNUSED const struct isl_format_layout *surf_fmtl =
+         isl_format_get_layout(info->surf->format);
+      MAYBE_UNUSED const struct isl_format_layout *view_fmtl =
+         isl_format_get_layout(info->surf->format);
+      assert(surf_fmtl->bpb == view_fmtl->bpb);
+      assert(surf_fmtl->bw == view_fmtl->bw);
+      assert(surf_fmtl->bh == view_fmtl->bh);
+   }
+
    s.SurfaceFormat = info->view->format;
 
 #if GEN_GEN <= 5
-- 
2.5.0.400.gff86faf