Patch "drm/radeon: mask out WC from BO on unsupported arches" has been added to the 4.4-stable tree

Patch "drm/radeon: mask out WC from BO on unsupported arches" has been added to the 4.4-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    drm/radeon: mask out WC from BO on unsupported arches

to the 4.4-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     drm-radeon-mask-out-wc-from-bo-on-unsupported-arches.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From c5244987394648913ae1a03879c58058a2fc2cee Mon Sep 17 00:00:00 2001
From: Oded Gabbay <oded.gabbay@gmail.com>
Date: Sat, 30 Jan 2016 07:59:33 +0200
Subject: drm/radeon: mask out WC from BO on unsupported arches
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
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From: Oded Gabbay <oded.gabbay@gmail.com>

commit c5244987394648913ae1a03879c58058a2fc2cee upstream.

Reviewed-by: Christian König <christian.koenig@amd.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Oded Gabbay <oded.gabbay@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/gpu/drm/radeon/radeon_object.c |    7 +++++++
 1 file changed, 7 insertions(+)

--- a/drivers/gpu/drm/radeon/radeon_object.c
+++ b/drivers/gpu/drm/radeon/radeon_object.c
@@ -33,6 +33,7 @@
 #include <linux/slab.h>
 #include <drm/drmP.h>
 #include <drm/radeon_drm.h>
+#include <drm/drm_cache.h>
 #include "radeon.h"
 #include "radeon_trace.h"
 
@@ -245,6 +246,12 @@ int radeon_bo_create(struct radeon_devic
 		DRM_INFO_ONCE("Please enable CONFIG_MTRR and CONFIG_X86_PAT for "
 			      "better performance thanks to write-combining\n");
 	bo->flags &= ~(RADEON_GEM_GTT_WC | RADEON_GEM_GTT_UC);
+#else
+	/* For architectures that don't support WC memory,
+	 * mask out the WC flag from the BO
+	 */
+	if (!drm_arch_can_wc_memory())
+		bo->flags &= ~RADEON_GEM_GTT_WC;
 #endif
 
 	radeon_ttm_placement_from_domain(bo, domain);


Patches currently in stable-queue which might be from oded.gabbay@gmail.com are

queue-4.4/drm-radeon-mask-out-wc-from-bo-on-unsupported-arches.patch
queue-4.4/drm-add-helper-to-check-for-wc-memory-support.patch