On Tue, 6 Oct 2020 at 14:40, Alper Nebi Yasak <alpernebiya...@gmail.com> wrote: > > 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 <alpernebiya...@gmail.com> > --- > I'm testing this with a lot of other patches to make the board work. The > actual tree I'm using is available here: > > https://github.com/alpernebbi/u-boot/commits/rk3399-gru-kevin/wip > (currently at commit c0dc4b42afe770671ce7bb0dd519d894a3acdea0) > > drivers/video/rockchip/rk_edp.c | 6 ++++++ > 1 file changed, 6 insertions(+) >
Reviewed-by: Simon Glass <s...@chromium.org>