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Diffstat (limited to 'meta-amd-bsp/recipes-kernel/linux/linux-yocto-4.19.8/2023-drm-amd-display-do-not-power-on-eDP-power-rail-early.patch')
-rw-r--r--meta-amd-bsp/recipes-kernel/linux/linux-yocto-4.19.8/2023-drm-amd-display-do-not-power-on-eDP-power-rail-early.patch66
1 files changed, 66 insertions, 0 deletions
diff --git a/meta-amd-bsp/recipes-kernel/linux/linux-yocto-4.19.8/2023-drm-amd-display-do-not-power-on-eDP-power-rail-early.patch b/meta-amd-bsp/recipes-kernel/linux/linux-yocto-4.19.8/2023-drm-amd-display-do-not-power-on-eDP-power-rail-early.patch
new file mode 100644
index 00000000..1f54793a
--- /dev/null
+++ b/meta-amd-bsp/recipes-kernel/linux/linux-yocto-4.19.8/2023-drm-amd-display-do-not-power-on-eDP-power-rail-early.patch
@@ -0,0 +1,66 @@
+From c13b2ae34acfe79b770361be5518c8728d22bbc2 Mon Sep 17 00:00:00 2001
+From: Anthony Koo <Anthony.Koo@amd.com>
+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 <Anthony.Koo@amd.com>
+Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
+Acked-by: Leo Li <sunpeng.li@amd.com>
+---
+ 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
+