[PATCH 17/21] drm/amd/display: Determine synchronization edge based on master's vsync

[Qingqing Zhuo]

From: Mikita Lipski <mikita.lipski at amd.com>

[Why&How]
The driver always wants to synchronize streams
to the first edge of master's vsync pulse.
In order to determine that we can read timing
flags that are used to program vsync.

Master stream's vsync polarity - Multi Display Stream Synchronization edge:

        Negative               -              Falling Edge

        Positive               -              Rising Edge

Signed-off-by: Mikita Lipski <mikita.lipski at amd.com>
Reviewed-by: Mikita Lipski <Mikita.Lipski at amd.com>
Reviewed-by: Sun peng Li <Sunpeng.Li at amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo at amd.com>
---
 .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 21 ++++++++++++++++---
 1 file changed, 18 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 92cee957b424..a57cbdb2c7a9 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -5394,9 +5394,14 @@ create_fake_sink(struct amdgpu_dm_connector *aconnector)
 static void set_multisync_trigger_params(
 		struct dc_stream_state *stream)
 {
+	struct dc_stream_state *master = NULL;
+
 	if (stream->triggered_crtc_reset.enabled) {
-		stream->triggered_crtc_reset.event = CRTC_EVENT_VSYNC_RISING;
-		stream->triggered_crtc_reset.delay = TRIGGER_DELAY_NEXT_LINE;
+		master = stream->triggered_crtc_reset.event_source;
+		stream->triggered_crtc_reset.event =
+			master->timing.flags.VSYNC_POSITIVE_POLARITY ?
+			CRTC_EVENT_VSYNC_RISING : CRTC_EVENT_VSYNC_FALLING;
+		stream->triggered_crtc_reset.delay = TRIGGER_DELAY_NEXT_PIXEL;
 	}
 }
 
@@ -5426,6 +5431,7 @@ static void set_master_stream(struct dc_stream_state *stream_set[],
 static void dm_enable_per_frame_crtc_master_sync(struct dc_state *context)
 {
 	int i = 0;
+	struct dc_stream_state *stream;
 
 	if (context->stream_count < 2)
 		return;
@@ -5437,9 +5443,18 @@ static void dm_enable_per_frame_crtc_master_sync(struct dc_state *context)
 		 * crtc_sync_master.multi_sync_enabled flag
 		 * For now it's set to false
 		 */
-		set_multisync_trigger_params(context->streams[i]);
 	}
+
 	set_master_stream(context->streams, context->stream_count);
+
+	for (i = 0; i < context->stream_count ; i++) {
+		stream = context->streams[i];
+
+		if (!stream)
+			continue;
+
+		set_multisync_trigger_params(stream);
+	}
 }
 
 static struct drm_display_mode *
-- 
2.17.1