Bug 582372

Summary:	gentoo-sources-4.5* : radeon driver doesn't seem to work during boot
Product:	Gentoo Linux	Reporter:	brankob
Component:	[OLD] Core system	Assignee:	Gentoo Linux bug wranglers <bug-wranglers>
Status:	RESOLVED INVALID
Severity:	normal
Priority:	Normal
Version:	unspecified
Hardware:	All
OS:	Linux
Whiteboard:
Package list:		Runtime testing required:	---
Attachments:	kernel .config file

Description brankob 2016-05-07 20:36:55 UTC

Created attachment 433550 [details]
kernel .config file

I have AMD system:

Phenom II 955 x4 with 4x2Gig of DDR3
HD6850 (=Barts) card with 3 monitors on it ( old elcheapo Samsungs Synmaster BM204 that do 1600x1200 at 20")


On this I usually run latest gentoo-sources that are set up with open source radeon driver built in. Up to latest gentoo-sources-4.4*, this worked fine.

With 4.5.0, all monitors would blank moment after kernel is loaded in GRUB adn stay blank during whole boot, which ends at text console login ( I normally do manual "systemctl isolate graphical target" to get into LightDM/XFCE).

After that, i can blindly type my username & pass to login and after "systemctl isolate graphical.target" everything wakes up and I get LightDM screen just fine.

greping through kernel log ring with dmesg and journalctl -b -t kernel doesn't list anything suspicious. It is as if kernel forgets to flip one last bit to turn picture generation on after setting the card...

XFCE works just fine, but I can't switch VT to VT-1..6 after that with CTRL-ALT-<1..6>. When I try that, everything on screen freezes and stays that way until I switch back with CTRL-ALT-7.

Since I have compiled-in radeon support as described in:

https://wiki.gentoo.org/wiki/Radeon

I had doublechecked that I do include right firmware blobs in the kernel.
Everything seems fine there.

Has anyone experienced anything like that ?

Comment 1 Alex Xu (Hello71) 2016-05-08 19:20:50 UTC

CONFIG_DRM_FBDEV_EMULATION:

Choose this option if you have a need for the legacy fbdev
support. Note that this support also provides the linux console
support on top of your modesetting driver.

If in doubt, say "Y".

Comment 2 brankob 2016-05-09 05:00:03 UTC

Aaaargh ! I'm such an idiot!

Thanks. Your kung fu is strong- well, stronger than mine anyway ;o)

Thanks.