drm/radeon: fixup issue with radeon and PAT support.

With new userspace libpciaccess we can get a conflicting mapping
on the PCIE GART table in the video RAM. Always try and map it _wc.

Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/drm_memory.c

diff --git a/drivers/gpu/drm/drm_memory.c b/drivers/gpu/drm/drm_memory.c
index 845081b4..0177012 100644
--- a/drivers/gpu/drm/drm_memory.c
+++ b/drivers/gpu/drm/drm_memory.c
@@ -167,6 +167,11 @@
 }
 EXPORT_SYMBOL(drm_core_ioremap);
 
+void drm_core_ioremap_wc(struct drm_map *map, struct drm_device *dev)
+{
+	map->handle = ioremap_wc(map->offset, map->size);
+}
+EXPORT_SYMBOL(drm_core_ioremap_wc);
 void drm_core_ioremapfree(struct drm_map *map, struct drm_device *dev)
 {
 	if (!map->handle || !map->size)

drivers/gpu/drm/radeon/radeon_cp.c

diff --git a/drivers/gpu/drm/radeon/radeon_cp.c b/drivers/gpu/drm/radeon/radeon_cp.c
index e53158f..f0de81a 100644
--- a/drivers/gpu/drm/radeon/radeon_cp.c
+++ b/drivers/gpu/drm/radeon/radeon_cp.c
@@ -1154,7 +1154,7 @@
 			dev_priv->gart_info.mapping.size =
 			    dev_priv->gart_info.table_size;
 
-			drm_core_ioremap(&dev_priv->gart_info.mapping, dev);
+			drm_core_ioremap_wc(&dev_priv->gart_info.mapping, dev);
 			dev_priv->gart_info.addr =
 			    dev_priv->gart_info.mapping.handle;