+ /* Write-combined CPU mappings of GTT cause GPU hangs with RV6xx
+ * See https://bugs.freedesktop.org/show_bug.cgi?id=91268
+ */
+ if (rdev->family >= CHIP_RV610 && rdev->family <= CHIP_RV635)
+ bo->flags &= ~(RADEON_GEM_GTT_WC | RADEON_GEM_GTT_UC);
+