[PATCH] drm/radeon: fix fence driver for dma ring when wb is disabled

[j.glisse at gmail.com]

From: Jerome Glisse <jglisse at redhat.com>

The dma ring can't write to register thus have to write to memory
its fence value. This ensure that it doesn't try to use scratch
register for dma ring fence driver.

Signed-off-by: Jerome Glisse <jglisse at redhat.com>
---
 drivers/gpu/drm/radeon/r600.c         | 3 ++-
 drivers/gpu/drm/radeon/radeon_fence.c | 2 +-
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/radeon/r600.c b/drivers/gpu/drm/radeon/r600.c
index a76eca1..2aaf147 100644
--- a/drivers/gpu/drm/radeon/r600.c
+++ b/drivers/gpu/drm/radeon/r600.c
@@ -2533,11 +2533,12 @@ void r600_dma_fence_ring_emit(struct radeon_device *rdev,
 {
 	struct radeon_ring *ring = &rdev->ring[fence->ring];
 	u64 addr = rdev->fence_drv[fence->ring].gpu_addr;
+
 	/* write the fence */
 	radeon_ring_write(ring, DMA_PACKET(DMA_PACKET_FENCE, 0, 0, 0));
 	radeon_ring_write(ring, addr & 0xfffffffc);
 	radeon_ring_write(ring, (upper_32_bits(addr) & 0xff));
-	radeon_ring_write(ring, fence->seq);
+	radeon_ring_write(ring, lower_32_bits(fence->seq));
 	/* generate an interrupt */
 	radeon_ring_write(ring, DMA_PACKET(DMA_PACKET_TRAP, 0, 0, 0));
 }
diff --git a/drivers/gpu/drm/radeon/radeon_fence.c b/drivers/gpu/drm/radeon/radeon_fence.c
index 22bd6c2..410a975 100644
--- a/drivers/gpu/drm/radeon/radeon_fence.c
+++ b/drivers/gpu/drm/radeon/radeon_fence.c
@@ -772,7 +772,7 @@ int radeon_fence_driver_start_ring(struct radeon_device *rdev, int ring)
 	int r;
 
 	radeon_scratch_free(rdev, rdev->fence_drv[ring].scratch_reg);
-	if (rdev->wb.use_event) {
+	if (rdev->wb.use_event || !radeon_ring_supports_scratch_reg(rdev, &rdev->ring[ring])) {
 		rdev->fence_drv[ring].scratch_reg = 0;
 		index = R600_WB_EVENT_OFFSET + ring * 4;
 	} else {
-- 
1.8.0