From b374f41be4f6d01d508813060c8084cbe2474154 Mon Sep 17 00:00:00 2001 From: Samson Tam Date: Mon, 4 Mar 2019 16:21:06 -0500 Subject: [PATCH] drm/amd/display: Link train only when link is DP and backend is enabled [ Upstream commit 66acd4418d7de131ef3831e52a8af3d2480e5b15 ] [Why] In certain cases we do link training when we don't have a backend. [How] In dc_link_set_preferred_link_settings(), store preferred link settings first and then verify that the link is DP and the link stream's backend is enabled. If either is false, then we will not do any link retraining. Signed-off-by: Samson Tam Reviewed-by: Aric Cyr Acked-by: Anthony Koo Acked-by: Bhawanpreet Lakha Signed-off-by: Alex Deucher Signed-off-by: Sasha Levin --- drivers/gpu/drm/amd/display/dc/core/dc.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/display/dc/core/dc.c b/drivers/gpu/drm/amd/display/dc/core/dc.c index 5af2ea1f201d..68529acba015 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc.c @@ -524,6 +524,14 @@ void dc_link_set_preferred_link_settings(struct dc *dc, struct dc_stream_state *link_stream; struct dc_link_settings store_settings = *link_setting; + link->preferred_link_setting = store_settings; + + /* Retrain with preferred link settings only relevant for + * DP signal type + */ + if (!dc_is_dp_signal(link->connector_signal)) + return; + for (i = 0; i < MAX_PIPES; i++) { pipe = &dc->current_state->res_ctx.pipe_ctx[i]; if (pipe->stream && pipe->stream->sink @@ -539,7 +547,10 @@ void dc_link_set_preferred_link_settings(struct dc *dc, link_stream = link->dc->current_state->res_ctx.pipe_ctx[i].stream; - link->preferred_link_setting = store_settings; + /* Cannot retrain link if backend is off */ + if (link_stream->dpms_off) + return; + if (link_stream) decide_link_settings(link_stream, &store_settings); -- 2.34.1