drm: Use register writes instead of BITBLT_MULTI packets for buffer swap blits
This takes up two more ring buffer entries per rectangle blitted but makes sure
the blit is performed top to bottom, reducing the likelyhood of tearing.
Signed-off-by: Dave Airlie <airlied@linux.ie>
diff --git a/drivers/char/drm/radeon_state.c b/drivers/char/drm/radeon_state.c
index bb4b2e1..feac5f0 100644
--- a/drivers/char/drm/radeon_state.c
+++ b/drivers/char/drm/radeon_state.c
@@ -1269,9 +1269,9 @@
DRM_DEBUG("dispatch swap %d,%d-%d,%d\n", x, y, w, h);
- BEGIN_RING(7);
+ BEGIN_RING(9);
- OUT_RING(CP_PACKET3(RADEON_CNTL_BITBLT_MULTI, 5));
+ OUT_RING(CP_PACKET0(RADEON_DP_GUI_MASTER_CNTL, 0));
OUT_RING(RADEON_GMC_SRC_PITCH_OFFSET_CNTL |
RADEON_GMC_DST_PITCH_OFFSET_CNTL |
RADEON_GMC_BRUSH_NONE |
@@ -1283,6 +1283,7 @@
/* Make this work even if front & back are flipped:
*/
+ OUT_RING(CP_PACKET0(RADEON_SRC_PITCH_OFFSET, 1));
if (dev_priv->current_page == 0) {
OUT_RING(dev_priv->back_pitch_offset);
OUT_RING(dev_priv->front_pitch_offset);
@@ -1291,6 +1292,7 @@
OUT_RING(dev_priv->back_pitch_offset);
}
+ OUT_RING(CP_PACKET0(RADEON_SRC_X_Y, 2));
OUT_RING((x << 16) | y);
OUT_RING((x << 16) | y);
OUT_RING((w << 16) | h);