Mesa (master): i965: Don't use CUBE wrap modes for integer formats on IVB/ BYT.

[Kenneth Graunke]

Module: Mesa
Branch: master
Commit: d4a5a61d445e683c20de00c1febe847b4c2db910
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=d4a5a61d445e683c20de00c1febe847b4c2db910

Author: Kenneth Graunke <kenneth at whitecape.org>
Date:   Mon Mar 28 20:07:13 2016 -0700

i965: Don't use CUBE wrap modes for integer formats on IVB/BYT.

There is no linear filtering for integer formats, so we should always
be using CLAMP_TO_EDGE mode.

Fixes 46 dEQP cases on Ivybridge (which were likely broken by commit
0faf26e6a0a34c3544644852802484f2404cc83e).

This workaround doesn't appear to be necessary on any other hardware;
I haven't found any documentation mentioning errata in this area.

v2: Only apply on Ivybridge/Baytrail to avoid regressing GLES3.1 tests.

Signed-off-by: Kenneth Graunke <kenneth at whitecape.org>
Reviewed-by: Jason Ekstrand <jason at jlekstrand.net> [v1]

---

 src/mesa/drivers/dri/i965/brw_sampler_state.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/src/mesa/drivers/dri/i965/brw_sampler_state.c b/src/mesa/drivers/dri/i965/brw_sampler_state.c
index 3bd22c7..1dc7d71 100644
--- a/src/mesa/drivers/dri/i965/brw_sampler_state.c
+++ b/src/mesa/drivers/dri/i965/brw_sampler_state.c
@@ -459,8 +459,12 @@ brw_update_sampler_state(struct brw_context *brw,
        target == GL_TEXTURE_CUBE_MAP_ARRAY) {
       /* Cube maps must use the same wrap mode for all three coordinate
        * dimensions.  Prior to Haswell, only CUBE and CLAMP are valid.
+       *
+       * Ivybridge and Baytrail seem to have problems with CUBE mode and
+       * integer formats.  Fall back to CLAMP for now.
        */
-      if (tex_cube_map_seamless || sampler->CubeMapSeamless) {
+      if ((tex_cube_map_seamless || sampler->CubeMapSeamless) &&
+          !(brw->gen == 7 && !brw->is_haswell && is_integer_format)) {
 	 wrap_s = BRW_TEXCOORDMODE_CUBE;
 	 wrap_t = BRW_TEXCOORDMODE_CUBE;
 	 wrap_r = BRW_TEXCOORDMODE_CUBE;