From: Fangzhi Zuo Jerry.Zuo@amd.com
stable inclusion from linux-4.19.155 commit 1c3b4b2d87c15acfcc4ea9861e071d6bca1f51de
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[ Upstream commit 95d620adb48f7728e67d82f56f756e8d451cf8d2 ]
[Why] Currently mode validation is bypassed if remote sink exists. That leads to mode set issue when a BW bottle neck exists in the link path, e.g., a DP-to-HDMI converter that only supports HDMI 1.4.
Any invalid mode passed to Linux user space will cause the modeset failure due to limitation of Linux user space implementation.
[How] Mode validation is skipped only if in edid override. For real remote sink, clock limit check should be done for HDMI remote sink.
Have HDMI related remote sink going through mode validation to elimiate modes which pixel clock exceeds BW limitation.
Signed-off-by: Fangzhi Zuo Jerry.Zuo@amd.com Reviewed-by: Hersen Wu hersenxs.wu@amd.com Acked-by: Eryk Brol eryk.brol@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- drivers/gpu/drm/amd/display/dc/core/dc_link.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c b/drivers/gpu/drm/amd/display/dc/core/dc_link.c index 2fb2c683ad54..fa0e6c8e2447 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c @@ -2009,7 +2009,7 @@ enum dc_status dc_link_validate_mode_timing( /* A hack to avoid failing any modes for EDID override feature on * topology change such as lower quality cable for DP or different dongle */ - if (link->remote_sinks[0]) + if (link->remote_sinks[0] && link->remote_sinks[0]->sink_signal == SIGNAL_TYPE_VIRTUAL) return DC_OK;
/* Passive Dongle */