From 506d2ee72af2ffc4173537eb001d7d4d57781ec7 Mon Sep 17 00:00:00 2001 From: Austin Zheng Date: Wed, 26 Jul 2023 10:40:48 -0400 Subject: drm/amd/display: Use DTBCLK as refclk instead of DPREFCLK [ Upstream commit 4a30cc2bd281fa176a68b5305cd3695d636152ad ] [Why] Flash of corruption observed when UCLK switching after transitioning from DTBCLK to DPREFCLK on subVP(DP) + subVP(HDMI) config Scenario where DPREFCLK is required instead of DTBCLK is not expected [How] Always set the DTBCLK source as DTBCLK0 Reviewed-by: Alvin Lee Acked-by: Tom Chung Signed-off-by: Austin Zheng Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher Signed-off-by: Sasha Levin --- drivers/gpu/drm/amd/display/dc/dcn32/dcn32_dccg.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/display/dc/dcn32/dcn32_dccg.c b/drivers/gpu/drm/amd/display/dc/dcn32/dcn32_dccg.c index ffbb739d85b6..8496ff4a25e3 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn32/dcn32_dccg.c +++ b/drivers/gpu/drm/amd/display/dc/dcn32/dcn32_dccg.c @@ -290,7 +290,8 @@ static void dccg32_set_dpstreamclk( struct dcn_dccg *dccg_dcn = TO_DCN_DCCG(dccg); /* set the dtbclk_p source */ - dccg32_set_dtbclk_p_src(dccg, src, otg_inst); + /* always program refclk as DTBCLK. No use-case expected to require DPREFCLK as refclk */ + dccg32_set_dtbclk_p_src(dccg, DTBCLK0, otg_inst); /* enabled to select one of the DTBCLKs for pipe */ switch (dp_hpo_inst) { -- cgit v1.2.3