drm/amd/display: add monitor patch to add T7 delay

[Why]
Specifically to one panel,
TCON is able to accept active video signal quickly, but
the Source Driver requires 2-3 frames of extra time.

It is a Panel issue since TCON needs to take care of
all Sink requirements including Source Driver. But in
this case it does not.

Customer is asking to add fixed T7 delay as panel
workaround.

[How]
Add monitor specific patch to add T7 delay
Signed-off-by: Anthony Koo <anthony.koo@amd.com>
Reviewed-by: Charlene Liu <Charlene.Liu@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/core/dc_link_hwss.c

@@ -162,6 +162,10 @@ bool edp_receiver_ready_T7(struct dc_link *link)
 			break;
 		udelay(25); //MAx T7 is 50ms
 	} while (++tries < 300);
+
+	if (link->local_sink->edid_caps.panel_patch.extra_t7_ms > 0)
+		udelay(link->local_sink->edid_caps.panel_patch.extra_t7_ms * 1000);
+
 	return result;
 }
 

drivers/gpu/drm/amd/display/dc/dc_types.h

@@ -202,6 +202,7 @@ struct dc_panel_patch {
 	unsigned int dppowerup_delay;
 	unsigned int extra_t12_ms;
 	unsigned int extra_delay_backlight_off;
+	unsigned int extra_t7_ms;
 };
 
 struct dc_edid_caps {