From: Aric Cyr <aric.cyr@xxxxxxx> [ Upstream commit 4e5183200d9b66695c754ef214933402056e7b95 ] [Why] If VUPDATE_END is before VUPDATE_START the delay calculated can become very large, causing a soft hang. [How] Take the absolute value of the difference between START and END. Signed-off-by: Aric Cyr <aric.cyr@xxxxxxx> Reviewed-by: Nicholas Kazlauskas <Nicholas.Kazlauskas@xxxxxxx> Acked-by: Qingqing Zhuo <qingqing.zhuo@xxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c index 60cea910759b..0c987b5d68e2 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c +++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c @@ -1651,6 +1651,8 @@ static void delay_cursor_until_vupdate(struct dc *dc, struct pipe_ctx *pipe_ctx) return; /* Stall out until the cursor update completes. */ + if (vupdate_end < vupdate_start) + vupdate_end += stream->timing.v_total; us_vupdate = (vupdate_end - vupdate_start + 1) * us_per_line; udelay(us_to_vupdate + us_vupdate); } -- 2.25.1
