i965: fix cube map lock-up / corruption

If we're using anything but GL_NEAREST sampling of a cube map, we need to
use the BRW_TEXCOORDMODE_CUBE texcoord wrap mode.  Before this, the GPU
would either lock up or subsequent texture filtering would be corrupted.

(cherry picked from master, commit 6f915b10d5963466567ea5445631192fd9c4e802)

1 files changed, 13 insertions, 9 deletions

diff --git a/src/mesa/drivers/dri/i965/brw_wm_sampler_state.c b/src/mesa/drivers/dri/i965/brw_wm_sampler_state.c
index 8c9cb789453..318b1453c4b 100644
--- a/src/mesa/drivers/dri/i965/brw_wm_sampler_state.c
+++ b/src/mesa/drivers/dri/i965/brw_wm_sampler_state.c
@@ -95,6 +95,7 @@ struct wm_sampler_key {
    int sampler_count;
 
    struct wm_sampler_entry {
+      GLenum tex_target;
       GLenum wrap_r, wrap_s, wrap_t;
       float maxlod, minlod;
       float lod_bias;
@@ -168,19 +169,20 @@ static void brw_update_sampler_state(struct wm_sampler_entry *key,
       }  
    }
 
-   sampler->ss1.r_wrap_mode = translate_wrap_mode(key->wrap_r);
-   sampler->ss1.s_wrap_mode = translate_wrap_mode(key->wrap_s);
-   sampler->ss1.t_wrap_mode = translate_wrap_mode(key->wrap_t);
-
-   /* Fulsim complains if I don't do this.  Hardware doesn't mind:
-    */
-#if 0
-   if (texObj->Target == GL_TEXTURE_CUBE_MAP_ARB) {
+   if (key->tex_target == GL_TEXTURE_CUBE_MAP &&
+       (key->minfilter != GL_NEAREST || key->magfilter != GL_NEAREST)) {
+      /* If we're using anything but nearest sampling for a cube map, we
+       * need to set this wrap mode to avoid GPU lock-ups.
+       */
       sampler->ss1.r_wrap_mode = BRW_TEXCOORDMODE_CUBE;
       sampler->ss1.s_wrap_mode = BRW_TEXCOORDMODE_CUBE;
       sampler->ss1.t_wrap_mode = BRW_TEXCOORDMODE_CUBE;
    }
-#endif
+   else {
+      sampler->ss1.r_wrap_mode = translate_wrap_mode(key->wrap_r);
+      sampler->ss1.s_wrap_mode = translate_wrap_mode(key->wrap_s);
+      sampler->ss1.t_wrap_mode = translate_wrap_mode(key->wrap_t);
+   }
 
    /* Set shadow function: 
     */
@@ -233,6 +235,8 @@ brw_wm_sampler_populate_key(struct brw_context *brw,
 	 struct gl_texture_image *firstImage =
 	    texObj->Image[0][intelObj->firstLevel];
 
+         entry->tex_target = texObj->Target;
+
 	 entry->wrap_r = texObj->WrapR;
 	 entry->wrap_s = texObj->WrapS;
 	 entry->wrap_t = texObj->WrapT;