From b2a93490201300a749ad261b5c5d05cb50179c44 Mon Sep 17 00:00:00 2001
From: Fudong Wang <Fudong.Wang@amd.com>
Date: Wed, 27 Jul 2022 12:01:29 +0800
Subject: [PATCH] drm/amd/display: clear optc underflow before turn off odm clock
Git-commit: b2a93490201300a749ad261b5c5d05cb50179c44
Patch-mainline: v6.0-rc2
References: git-fixes
[Why]
After ODM clock off, optc underflow bit will be kept there always and clear not work.
We need to clear that before clock off.
[How]
Clear that if have when clock off.
Reviewed-by: Alvin Lee <alvin.lee2@amd.com>
Acked-by: Tom Chung <chiahsuan.chung@amd.com>
Signed-off-by: Fudong Wang <Fudong.Wang@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/gpu/drm/amd/display/dc/dcn10/dcn10_optc.c | 5 +++++
1 file changed, 5 insertions(+)
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 e1a9a45b03b6..3fc300cd1ce9 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_optc.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_optc.c
@@ -465,6 +465,11 @@ void optc1_enable_optc_clock(struct timing_generator *optc, bool enable)
OTG_CLOCK_ON, 1,
1, 1000);
} else {
+
+ //last chance to clear underflow, otherwise, it will always there due to clock is off.
+ if (optc->funcs->is_optc_underflow_occurred(optc) == true)
+ optc->funcs->clear_optc_underflow(optc);
+
REG_UPDATE_2(OTG_CLOCK_CONTROL,
OTG_CLOCK_GATE_DIS, 0,
OTG_CLOCK_EN, 0);
--
2.35.3