From c13b2ae34acfe79b770361be5518c8728d22bbc2 Mon Sep 17 00:00:00 2001 From: Anthony Koo Date: Fri, 10 May 2019 14:57:48 -0400 Subject: [PATCH 2023/2940] 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 --- drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c | 3 --- drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c | 3 --- 2 files changed, 6 deletions(-) diff --git a/drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c b/drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c index f3dd117b4831..3042741b165a 100644 --- a/drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c +++ b/drivers/gpu/drm/amd/display/dc/dce110/dce110_hw_sequencer.c @@ -2352,9 +2352,6 @@ static void init_hw(struct dc *dc) * default signal on connector). */ 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); } diff --git a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c index c1623b80e131..409926685cb1 100644 --- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c +++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_hw_sequencer.c @@ -1102,9 +1102,6 @@ static void dcn10_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); /* Check for enabled DIG to identify enabled display */ -- 2.17.1