drm/radeon/r6xx: fix DMA engine for ttm bo transfers

count must be a multiple of 2. Fixes crashes on
R6xx chips reported by a number of people.

Cc: Borislav Petkov <bp@alien8.de>
Cc: Markus Trippelsdorf <markus@trippelsdorf.de>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Tested-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --git a/drivers/gpu/drm/radeon/r600.c b/drivers/gpu/drm/radeon/r600.c
index 2aaf147969bd8ef80522af9e38900e5987002d4c..9f4ce5eb9e9cb5f426e6761cfb6ad00a88e40a25 100644 (file)
--- a/drivers/gpu/drm/radeon/r600.c
+++ b/drivers/gpu/drm/radeon/r600.c
@@ -2636,8 +2636,8 @@ int r600_copy_dma(struct radeon_device *rdev,
 
        for (i = 0; i < num_loops; i++) {
                cur_size_in_dw = size_in_dw;
-               if (cur_size_in_dw > 0xFFFF)
-                       cur_size_in_dw = 0xFFFF;
+               if (cur_size_in_dw > 0xFFFE)
+                       cur_size_in_dw = 0xFFFE;
                size_in_dw -= cur_size_in_dw;
                radeon_ring_write(ring, DMA_PACKET(DMA_PACKET_COPY, 0, 0, cur_size_in_dw));
                radeon_ring_write(ring, dst_offset & 0xfffffffc);