drm/msm/dp: skip checking LINK_STATUS_UPDATED bit

Browse source

Some dongle will not clear LINK_STATUS_UPDATED bit after
DPCD read which cause link training failed. This patch
just read 6 bytes of DPCD link status from sink and return
without checking LINK_STATUS_UPDATED bit.
Only 8 bits are used to represent link rate at sinker DPCD.
The really link rate is 2.7Mb times the 8 bits value.
For example, 0x0A at DPCD is equal to 2.7Gb (10 * 2.7Mb).
This patch also convert 8 bits value of DPCD to really link
rate to fix worng link rate error during phy compliance test.

Fixes: 6625e2637d ("drm/msm/dp: DisplayPort PHY compliance tests fixup")
Signed-off-by: Kuogee Hsieh <khsieh@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>

...

This commit is contained in:

Kuogee Hsieh 2020-11-03 12:49:01 -08:00 • committed by Rob Clark

parent 231a04fcc6

commit ea530388e6

2 changed files with 20 additions and 29 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

20

drivers/gpu/drm/msm/dp/dp_ctrl.c

View file

29

drivers/gpu/drm/msm/dp/dp_link.c

View file