Mesa (master): isl/state: Don't set QPitch for GEN4_3D surfaces

[Jason Ekstrand]

Module: Mesa
Branch: master
Commit: 00e79cec995b8c654783860613bc36b90d3d33dc
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=00e79cec995b8c654783860613bc36b90d3d33dc

Author: Jason Ekstrand <jason.ekstrand at intel.com>
Date:   Thu Sep  8 10:23:47 2016 -0700

isl/state: Don't set QPitch for GEN4_3D surfaces

Signed-off-by: Jason Ekstrand <jason at jlekstrand.net>
Reviewed-by: Chad Versace <chadversary at chromium.org>

---

 src/intel/isl/isl_surface_state.c | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/src/intel/isl/isl_surface_state.c b/src/intel/isl/isl_surface_state.c
index da1544b7..cd7a084 100644
--- a/src/intel/isl/isl_surface_state.c
+++ b/src/intel/isl/isl_surface_state.c
@@ -172,7 +172,6 @@ get_qpitch(const struct isl_surf *surf)
    default:
       unreachable("Bad isl_surf_dim");
    case ISL_DIM_LAYOUT_GEN4_2D:
-   case ISL_DIM_LAYOUT_GEN4_3D:
       if (GEN_GEN >= 9) {
          return isl_surf_get_array_pitch_el_rows(surf);
       } else {
@@ -199,6 +198,22 @@ get_qpitch(const struct isl_surf *surf)
        *    slices.
        */
       return isl_surf_get_array_pitch_el(surf);
+   case ISL_DIM_LAYOUT_GEN4_3D:
+      /* QPitch doesn't make sense for ISL_DIM_LAYOUT_GEN4_3D since it uses a
+       * different pitch at each LOD.  Also, the QPitch field is ignored for
+       * these surfaces.  From the Broadwell PRM documentation for QPitch:
+       *
+       *    This field specifies the distance in rows between array slices. It
+       *    is used only in the following cases:
+       *     - Surface Array is enabled OR
+       *     - Number of Mulitsamples is not NUMSAMPLES_1 and Multisampled
+       *       Surface Storage Format set to MSFMT_MSS OR
+       *     - Surface Type is SURFTYPE_CUBE
+       *
+       * None of the three conditions above can possibly apply to a 3D surface
+       * so it is safe to just set QPitch to 0.
+       */
+      return 0;
    }
 }
 #endif /* GEN_GEN >= 8 */