[PATCH 4.2.y-ckt 018/305] drm/radeon: Disable uncacheable CPU mappings of GTT with RV6xx
From: Kamal Mostafa
Date: Fri Jan 15 2016 - 20:35:44 EST
4.2.8-ckt2 -stable review patch. If anyone has any objections, please let me know.
---8<------------------------------------------------------------
From: =?UTF-8?q?Michel=20D=C3=A4nzer?= <michel.daenzer@xxxxxxx>
commit 96ea47c0ec8c012509116bee8c57414281428fc4 upstream.
They reportedly cause random GPU hangs.
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=91268
Reviewed-by: Christian KÃnig <christian.koenig@xxxxxxx>
Signed-off-by: Michel DÃnzer <michel.daenzer@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
---
drivers/gpu/drm/radeon/radeon_object.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/gpu/drm/radeon/radeon_object.c b/drivers/gpu/drm/radeon/radeon_object.c
index 6763627..6e88c1b0 100644
--- a/drivers/gpu/drm/radeon/radeon_object.c
+++ b/drivers/gpu/drm/radeon/radeon_object.c
@@ -221,6 +221,12 @@ int radeon_bo_create(struct radeon_device *rdev,
if (!(rdev->flags & RADEON_IS_PCIE))
bo->flags &= ~(RADEON_GEM_GTT_WC | RADEON_GEM_GTT_UC);
+ /* 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);
+
#ifdef CONFIG_X86_32
/* XXX: Write-combined CPU mappings of GTT seem broken on 32-bit
* See https://bugs.freedesktop.org/show_bug.cgi?id=84627
--
1.9.1