[PATCH 3.19.y-ckt 026/107] drm/radeon: fix HDP flushing

[Kamal Mostafa]

3.19.8-ckt5 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: Grigori Goronzy <greg at chown.ath.cx>

commit 54e03986133468e02cb01b76215e4d53a9cf6380 upstream.

This was regressed by commit 39e7f6f8, although I don't know of any
actual issues caused by it.

The storage domain is read without TTM locking now, but the lock
never helped to prevent any races.

Reviewed-by: Christian König <christian.koenig at amd.com>
Signed-off-by: Grigori Goronzy <greg at chown.ath.cx>
Signed-off-by: Alex Deucher <alexander.deucher at amd.com>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 drivers/gpu/drm/radeon/radeon_gem.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/gpu/drm/radeon/radeon_gem.c b/drivers/gpu/drm/radeon/radeon_gem.c
index ac3c131..e370cb4 100644
--- a/drivers/gpu/drm/radeon/radeon_gem.c
+++ b/drivers/gpu/drm/radeon/radeon_gem.c
@@ -471,6 +471,7 @@ int radeon_gem_wait_idle_ioctl(struct drm_device *dev, void *data,
 		r = ret;
 
 	/* Flush HDP cache via MMIO if necessary */
+	cur_placement = ACCESS_ONCE(robj->tbo.mem.mem_type);
 	if (rdev->asic->mmio_hdp_flush &&
 	    radeon_mem_type_to_domain(cur_placement) == RADEON_GEM_DOMAIN_VRAM)
 		robj->rdev->asic->mmio_hdp_flush(rdev);
-- 
1.9.1