Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6

[uclinux-h8/linux.git] / drivers / gpu / drm / i915 / i915_gem_tiling.c

diff --git a/drivers/gpu/drm/i915/i915_gem_tiling.c b/drivers/gpu/drm/i915/i915_gem_tiling.c
index 633bd1f..d61e74a 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem_tiling.c
+++ b/drivers/gpu/drm/i915/i915_gem_tiling.c
@@ -183,8 +183,18 @@ i915_gem_detect_bit_6_swizzle(struct drm_device *dev)
                if (IS_GEN4(dev)) {
                        uint32_t ddc2 = I915_READ(DCC2);
 
-                       if (!(ddc2 & DCC2_MODIFIED_ENHANCED_DISABLE))
+                       if (!(ddc2 & DCC2_MODIFIED_ENHANCED_DISABLE)) {
+                               /* Since the swizzling may vary within an
+                                * object, we have no idea what the swizzling
+                                * is for any page in particular. Thus we
+                                * cannot migrate tiled pages using the GPU,
+                                * nor can we tell userspace what the exact
+                                * swizzling is for any object.
+                                */
                                dev_priv->quirks |= QUIRK_PIN_SWIZZLED_PAGES;
+                               swizzle_x = I915_BIT_6_SWIZZLE_UNKNOWN;
+                               swizzle_y = I915_BIT_6_SWIZZLE_UNKNOWN;
+                       }
                }
 
                if (dcc == 0xffffffff) {