u-boot-brain/drivers/video/rockchip
Alper Nebi Yasak 127c8d85cf video: rockchip: Add missing dpcd_write() call to link_train_ce()
Found this by comparing it to the coreboot driver, a form of this call
was introduced there in their commit b9a7877568cf ("rockchip/*: refactor
edp driver"). This is copy-pasted from U-Boot's link_train_cr() slightly
above it.

Without this on a gru-kevin chromebook, I have:

    clock recovery at voltage 0 pre-emphasis 0
    requested signal parameters: lane 0 voltage 0.4V pre_emph 3.5dB
    requested signal parameters: lane 1 voltage 0.4V pre_emph 3.5dB
    requested signal parameters: lane 2 voltage 0.4V pre_emph 3.5dB
    requested signal parameters: lane 3 voltage 0.4V pre_emph 3.5dB
    using signal parameters: voltage 0.4V pre_emph 3.5dB
    requested signal parameters: lane 0 voltage 0.4V pre_emph 3.5dB
    requested signal parameters: lane 1 voltage 0.4V pre_emph 3.5dB
    requested signal parameters: lane 2 voltage 0.4V pre_emph 3.5dB
    requested signal parameters: lane 3 voltage 0.4V pre_emph 3.5dB
    using signal parameters: voltage 0.4V pre_emph 3.5dB
    requested signal parameters: lane 0 voltage 0.4V pre_emph 3.5dB
    requested signal parameters: lane 1 voltage 0.4V pre_emph 3.5dB
    requested signal parameters: lane 2 voltage 0.4V pre_emph 3.5dB
    requested signal parameters: lane 3 voltage 0.4V pre_emph 3.5dB
    using signal parameters: voltage 0.4V pre_emph 3.5dB
    requested signal parameters: lane 0 voltage 0.4V pre_emph 3.5dB
    requested signal parameters: lane 1 voltage 0.4V pre_emph 3.5dB
    requested signal parameters: lane 2 voltage 0.4V pre_emph 3.5dB
    requested signal parameters: lane 3 voltage 0.4V pre_emph 3.5dB
    using signal parameters: voltage 0.4V pre_emph 3.5dB
    requested signal parameters: lane 0 voltage 0.4V pre_emph 3.5dB
    requested signal parameters: lane 1 voltage 0.4V pre_emph 3.5dB
    requested signal parameters: lane 2 voltage 0.4V pre_emph 3.5dB
    requested signal parameters: lane 3 voltage 0.4V pre_emph 3.5dB
    using signal parameters: voltage 0.4V pre_emph 3.5dB
    channel eq failed, ret=-5
    link train failed!
    rk_vop_probe() Device failed: ret=-5

With this, it looks like training succeeds:

    clock recovery at voltage 0 pre-emphasis 0
    requested signal parameters: lane 0 voltage 0.4V pre_emph 3.5dB
    requested signal parameters: lane 1 voltage 0.4V pre_emph 3.5dB
    requested signal parameters: lane 2 voltage 0.4V pre_emph 3.5dB
    requested signal parameters: lane 3 voltage 0.4V pre_emph 3.5dB
    using signal parameters: voltage 0.4V pre_emph 3.5dB
    requested signal parameters: lane 0 voltage 0.4V pre_emph 6dB
    requested signal parameters: lane 1 voltage 0.4V pre_emph 6dB
    requested signal parameters: lane 2 voltage 0.4V pre_emph 6dB
    requested signal parameters: lane 3 voltage 0.4V pre_emph 6dB
    using signal parameters: voltage 0.4V pre_emph 6dB
    requested signal parameters: lane 0 voltage 0.4V pre_emph 0dB
    requested signal parameters: lane 1 voltage 0.4V pre_emph 0dB
    requested signal parameters: lane 2 voltage 0.4V pre_emph 0dB
    requested signal parameters: lane 3 voltage 0.4V pre_emph 0dB
    using signal parameters: voltage 0.4V pre_emph 0dB
    channel eq at voltage 0 pre-emphasis 0
    config video failed
    rk_vop_probe() Device failed: ret=-110

The "config video failed" error also goes away when I disable higher
log levels, and it claims to have successfully probed the device.

Signed-off-by: Alper Nebi Yasak <alpernebiyasak@gmail.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Kever Yang<kever.yang@rock-chips.com>
2020-10-30 18:20:03 +08:00
..
Kconfig video: rockchip: fix HDMI 4K resolution 2020-06-29 17:53:16 +02:00
Makefile SPDX: Convert all of our single license tags to Linux Kernel style 2018-05-07 09:34:12 -04:00
rk3288_hdmi.c common: Drop log.h from common header 2020-05-18 21:19:18 -04:00
rk3288_mipi.c common: Drop log.h from common header 2020-05-18 21:19:18 -04:00
rk3288_vop.c drivers: rename drivers to match compatible string 2020-07-09 18:57:22 -06:00
rk3399_hdmi.c rockchip: use 'arch-rockchip' as header file path 2019-05-01 00:00:05 +02:00
rk3399_mipi.c common: Drop log.h from common header 2020-05-18 21:19:18 -04:00
rk3399_vop.c common: Drop log.h from common header 2020-05-18 21:19:18 -04:00
rk_edp.c video: rockchip: Add missing dpcd_write() call to link_train_ce() 2020-10-30 18:20:03 +08:00
rk_hdmi.c common: Drop log.h from common header 2020-05-18 21:19:18 -04:00
rk_hdmi.h SPDX: Convert all of our single license tags to Linux Kernel style 2018-05-07 09:34:12 -04:00
rk_lvds.c common: Drop log.h from common header 2020-05-18 21:19:18 -04:00
rk_mipi.c common: Drop log.h from common header 2020-05-18 21:19:18 -04:00
rk_mipi.h SPDX: Convert all of our single license tags to Linux Kernel style 2018-05-07 09:34:12 -04:00
rk_vop.c common: Drop linux/bitops.h from common header 2020-05-18 21:19:23 -04:00
rk_vop.h rockchip: use 'arch-rockchip' as header file path 2019-05-01 00:00:05 +02:00