[M] Change in coreboot[main]: soc/mediatek: Introduce mtk_edp_enable() to fix eDP init flow

[Yu-Ping Wu (Code Review)]

Attention is currently required from: Hung-Te Lin, Yu-Ping Wu.

Hello Hung-Te Lin, Yidi Lin, build bot (Jenkins),

I'd like you to reexamine a change. Please visit

https://review.coreboot.org/c/coreboot/+/86028?usp=email

to look at the new patch set (#5).

The following approvals got outdated and were removed:
Verified-1 by build bot (Jenkins)

Change subject: soc/mediatek: Introduce mtk_edp_enable() to fix eDP init flow
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soc/mediatek: Introduce mtk_edp_enable() to fix eDP init flow

In the current eDP initialization flow, eDP is configured and enabled
before display data pipe (DDP) initialization. The init flow is wrong,
because eDP should be enabled only after DDP is correctly set up. The
wrong flow may lead to garbage display between enabling eDP and
configuring DDP.

To fix the problem, the dptx_video_enable(true) call needs to be moved
after mtk_ddp_mode_set(). Introduce a new API mtk_edp_enable() for eDP
enablement, to be separated from the existing mtk_edp_init(). The fixed
eDP init flow is: mtk_edp_init -> mtk_ddp_mode_set -> mtk_edp_enable.

Change-Id: Ief847320caca1af1c6deb242dc224e7698a6603c
Signed-off-by: Yu-Ping Wu 
---
M src/soc/mediatek/common/display.c
M src/soc/mediatek/common/dp/dptx.c
M src/soc/mediatek/common/dp/include/soc/dptx_common.h
3 files changed, 35 insertions(+), 15 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/28/86028/5