[PATCH 14/16] drm/amd/display: HLK Periodic Frame Notification test failed

[sunpeng.li at amd.com]

From: Murton Liu <murton.liu at amd.com>

[Why]
Due to a small pre-fetch window, the active vline timing is a couple
of lines off when compared to what it should be.

[How]
Changed the calculation for the start vline to account for this window.

Signed-off-by: Murton Liu <murton.liu at amd.com>
Reviewed-by: Aric Cyr <Aric.Cyr at amd.com>
Acked-by: Leo Li <sunpeng.li at amd.com>
---
 drivers/gpu/drm/amd/display/dc/dcn10/dcn10_optc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_optc.c b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_optc.c
index ad46294..5462668 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_optc.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_optc.c
@@ -150,7 +150,7 @@ void optc1_program_vline_interrupt(
 		req_delta_lines--;
 
 	if (req_delta_lines > vsync_line)
-		start_line = dc_crtc_timing->v_total - (req_delta_lines - vsync_line) - 1;
+		start_line = dc_crtc_timing->v_total - (req_delta_lines - vsync_line) + 2;
 	else
 		start_line = vsync_line - req_delta_lines;
 
-- 
2.7.4