[Bug 108826] [GLK DSI] Black screen after grub - Ubuntu 18.04 - kernel latest tip 21.11.2018

[bugzilla-daemon at freedesktop.org]

https://bugs.freedesktop.org/show_bug.cgi?id=108826

--- Comment #138 from Stanislav Lisovskiy <stanislav.lisovskiy at intel.com> ---
(In reply to Microtech from comment #134)
> Created attachment 144392 [details]
> DSN
> 
> (In reply to Stanislav Lisovskiy from comment #132)
> > Miroslaw, do you happen to have any other documents for Microtech Etab?
> > Would be nice to see the actual schematics..
> 
> Hi Stanislav, in attached you can find all the docs showing connections
> between PCBA and all the rest. I hope you can find a solution quickly,
> because this is the last issue we have to solve before to make available the
> Linux systems on the e-tab Pro.
> Please let us know.

I checked the schematics -  pins look correct(i.e GPIO 135 is reset, GPIO 144
power and GPIO 145 is backlight). I guess we might be missing something in vbt
and/or during port initilization stage. Do you have any documents containing
more precise panel initialization sequence? I mean exact sequence of command
which is expected by this panel, for example exact DCS commands need to be sent
for example. 
The pdf attached by Miroslaw has power-on, power-off sequence which matches
what we doing already, however there is no dcs command description.
I also checked Windows driver - MIPI DSI initilization looks roughly the same,
however as I'm not familiar with that codebase which is quite big, it might
take a lot of time to figure out some minor differences. I would say the best
way to go would be to get exact example initilization sequence from panel
vendor and then compare everything what we send to that.

-- 
You are receiving this mail because:
You are on the CC list for the bug.
You are the QA Contact for the bug.
You are the assignee for the bug.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.freedesktop.org/archives/intel-gfx-bugs/attachments/20190531/5a7bab95/attachment-0001.html>