From 45021f8ea536b5d40decf35af6f91116dd112787 Mon Sep 17 00:00:00 2001 From: Anthony Koo Date: Fri, 10 May 2019 14:57:48 -0400 Subject: [PATCH] drm/amd/display: do not power on eDP power rail early [Why] Modern Standby may toggle display adapter state between D0 and D3 state unpredictably. But events that cause transition to D0 are not always resulting in a display light up scenario. Modern eDP panels should be able to power on panel logic quickly upon VDD going high. Based on spec, the T3 time between VDD on and HPD high can be between 0 and 80 ms. Doing any tricky sorts of optimization by powering on panel VDD early during D0 transition on can negatively impact other features due to unnecessary power drain and toggling when final system state does not intend for the panel to be lit up. We need OEMs to source higher end panels that have T3 time close to 0 if they want quick S3/Modern Standby resume times. [How] Remove panel VDD power on in init_hw Signed-off-by: Anthony Koo Reviewed-by: Tony Cheng Acked-by: Leo Li Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c | 3 --- 1 file changed, 3 deletions(-) diff --git a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c index 2a34447112e9..f6e25f75a0a9 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c +++ b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c @@ -547,9 +547,6 @@ static void dcn20_init_hw(struct dc *dc) */ struct dc_link *link = dc->links[i]; - if (link->link_enc->connector.id == CONNECTOR_ID_EDP) - dc->hwss.edp_power_control(link, true); - link->link_enc->funcs->hw_init(link->link_enc); } } -- 2.45.2