FAILED: patch "[PATCH] drm/amdgpu: mask out WC from BO on unsupported arches" failed to apply to 4.4-stable tree

[<gregkh@linuxfoundation.org>]

The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable@vger.kernel.org>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

>From a187f17f0e15a046aa5d7263b35df55230d92779 Mon Sep 17 00:00:00 2001
From: Oded Gabbay <oded.gabbay@gmail.com>
Date: Sat, 30 Jan 2016 07:59:34 +0200
Subject: [PATCH] drm/amdgpu: mask out WC from BO on unsupported arches
MIME-Version: 1.0
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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>
Cc: stable@vger.kernel.org

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
index a2a16acee34d..b8fbbd7699e4 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c
@@ -33,6 +33,7 @@
 #include <linux/slab.h>
 #include <drm/drmP.h>
 #include <drm/amdgpu_drm.h>
+#include <drm/drm_cache.h>
 #include "amdgpu.h"
 #include "amdgpu_trace.h"
 
@@ -261,6 +262,13 @@ int amdgpu_bo_create_restricted(struct amdgpu_device *adev,
 				       AMDGPU_GEM_DOMAIN_OA);
 
 	bo->flags = flags;
+
+	/* For architectures that don't support WC memory,
+	 * mask out the WC flag from the BO
+	 */
+	if (!drm_arch_can_wc_memory())
+		bo->flags &= ~AMDGPU_GEM_CREATE_CPU_GTT_USWC;
+
 	amdgpu_fill_placement_to_bo(bo, placement);
 	/* Kernel allocation are uninterruptible */
 	r = ttm_bo_init(&adev->mman.bdev, &bo->tbo, size, type,