This is with intel driver 2.20.19:
00:02.0 VGA compatible controller: Intel Corporation Atom Processor D4xx/D5xx/N4xx/N5xx Integrated Graphics Controller (prog-if 00 [VGA controller])
[ 43.928] (--) intel(0): Integrated Graphics Chipset: Intel(R) Pineview GM
When X is being started by gdm, we get a black flickering, despite plymouth correctly retaining splash to prevent this flickering.
"Correctly" may turn out to be an overstatement. Have you checked drm.debug=6 dmesg to see why the modeset is required?
Created attachment 75904 [details]
drm.debug=6 dmesg output
here is the logs.
I've noticed similar flicker on other intel platform, I'll give the debug output later.
From the kernel perspective, everything worked fine. plymouth triggered a modeset and installed its fb, then X starts and just triggers a set-base rather than a full modeset. That should be seamless (at no point did we power down the pipe to make the changes).
So, the question then becomes did UXA render a visible black frame before filling it with the copy from fbcon?
(In reply to comment #3)
> So, the question then becomes did UXA render a visible black frame before
> filling it with the copy from fbcon?
Any way to debug this ?
Using SNA, --enable-debug=full. Using UXA, switch to SNA... :|
(In reply to comment #5)
> Using SNA, --enable-debug=full. Using UXA, switch to SNA... :|
switching to SNA fixed the back flickering..
I'll test on the other hardware where I saw the bug before closing this bug.
ok, tested on another system :
00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09) (prog-if 00 [VGA controller])
Switching to SNA fixed the black flicker too..