Hi Logan,
On the positive, you do not seem to be having any more EDID issues once you have switched to the other LCD screen.
But this line seems a worry:
[ 27.168859] nouveau 0000:f0:10.0: gr: intr 00100000 [ERROR] nsource
00000010 [LIMIT_COLOR] nstatus 04000000 [PROTECTION_FAULT] ch 1
[0008e000 Xorg[853]] subc 4 class 009f mthd 0308 data 04380780
Does this only occur when lightdm attempts to start?
Does the nouveau fb console seem to work fine or does this only occur when xorg starts up?
Can you please confirm that the old "nv" driver is blacklisted and not conflicting with "nouveau"?
Also, do you happen to have an xorg.conf file as this shouldn't be required.
Lastly, what debian repo's are you on, i.e. are you on stable or testing (stretch)? as it could be something with the xorg drm driver not playing nice with the much newer kernel... Not sure, but something to consider.
The reason why the earlier kernel builds (i.e. < 4.4.0-rc7) didn’t work was that they were set up particularly for the PMAC 11.2 machines and not the older PMAC 7.2 Powermac G5's. There were drivers missing specifically for the AGP Powermac G5's.
OTOH, Aiden was the first one i believe who has a PMAC 7.2 machine that actually gave some feedback. So we adjusted the config to also suit those machines.
I build these kernels for my own testing purposes and originally just for my own G5 Quad (PMAC 11.2). But since it it may help others in the community, i can try to adjust the config to suit other G5's as well.
That's why feedback is great as i don't have other G5 models to test on. If it seems to help others in the Debian community to get their Powermac G5's running, then why not change the config to suit more machines i say
It still seems to missing some drivers, but hopefully with feedback we can try to sort them out. With my kernel builds, only try the builds > 4.4.0-rc7 as these have the kernel config changed for the AGP Powermac G5's.
Lastly, i am on Debian testing repos so it might explain why you have the version conflict when installing the headers as it might have newer dependancies.
Keep on sending logs as it helps to diagnose what’s wrong with your particular config.