From 63570e578094b4f0b6b8c6ac4a68195455733e31 Mon Sep 17 00:00:00 2001 From: Dale Zhao Date: Fri, 16 Jul 2021 09:38:17 +0800 Subject: [PATCH] drm/amd/display: ensure dentist display clock update finished in DCN20 commit b53e041d8e4308f7324999398aec092dbcb130f5 upstream. [Why] We don't check DENTIST_DISPCLK_CHG_DONE to ensure dentist display clockis updated to target value. In some scenarios with large display clock margin, it will deliver unfinished display clock and cause issues like display black screen. [How] Checking DENTIST_DISPCLK_CHG_DONE to ensure display clock has been update to target value before driver do other clock related actions. Reviewed-by: Cyr Aric Acked-by: Solomon Chiu Signed-off-by: Dale Zhao Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/amd/display/dc/clk_mgr/dcn20/dcn20_clk_mgr.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn20/dcn20_clk_mgr.c b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn20/dcn20_clk_mgr.c index f2114bc910bf..6b744edcd75f 100644 --- a/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn20/dcn20_clk_mgr.c +++ b/drivers/gpu/drm/amd/display/dc/clk_mgr/dcn20/dcn20_clk_mgr.c @@ -135,7 +135,7 @@ void dcn20_update_clocks_update_dentist(struct clk_mgr_internal *clk_mgr) REG_UPDATE(DENTIST_DISPCLK_CNTL, DENTIST_DISPCLK_WDIVIDER, dispclk_wdivider); -// REG_WAIT(DENTIST_DISPCLK_CNTL, DENTIST_DISPCLK_CHG_DONE, 1, 5, 100); + REG_WAIT(DENTIST_DISPCLK_CNTL, DENTIST_DISPCLK_CHG_DONE, 1, 50, 1000); REG_UPDATE(DENTIST_DISPCLK_CNTL, DENTIST_DPPCLK_WDIVIDER, dppclk_wdivider); REG_WAIT(DENTIST_DISPCLK_CNTL, DENTIST_DPPCLK_CHG_DONE, 1, 5, 100);