Radeon RV516 (X1300) not functioning on Xserve

Dachnaz · Last edited by Dachnaz on Thu Nov 21, 2013 6:49 pm; edited 1 time in total

I've installed Gentoo on an Xserve 3,1. The trouble is, this beast does not play nice with kernel modesetting. In fact, the only way I can get the system to boot is to disable kernel modesetting. I've done quite a bit of searching all across the Internets, but it seems that Linux has changed a lot since I was in high school. Is there some way to run X using the old drivers that modeset in userspace?

eccerr0r · Posted: Mon Nov 18, 2013 10:54 pm Post subject:

Likely the old versions of the driver doesn't understand the "newer" hardware (it's been a while since the userspace kernel drivers were available), so seems you have a catch-22 here... What is wrong with KMS?
_________________
Intel Core i7 2700K/Radeon R7 250/24GB DDR3/256GB SSD
What am I supposed watching?

salahx · Guru Joined: 12 Mar 2005 Posts: 530

You might not need disable KMS but you may need to disable video acceleration. I've had 2 computers that problem with acceleration, both nvidia, one NV40 and the other NV11. I ha to turn of video acceleration with nouveau.noaccel=1 to get the to work (around 3.7 the nouveau refactored the driver significantly, fixing the issue with the NV40 one. NV11 still remains unusable, not due to any fault in the nouveau driver but it only has 32MB of VRAM).

Dachnaz · Posted: Wed Nov 20, 2013 7:53 pm Post subject:

The problem is my kernel will panic if modesetting is allowed and I use a DRM driver. Similarly, as soon as I modprobe radeon, kernel modesetting becomes enabled, fb reports conflicting fb usage between radeondrmfb and EFI VGA driver, and the kernel panics. Hm. Maybe it is a compatibility issue with the Radeon RV516 and the radeon drivers?

EDIT:
I've noticed that the kernel also will panic at boot if EFI framebuffer support is not present.

EDITED EDIT:
Maybe it's just that nothing is getting displayed!

Dachnaz · Posted: Wed Nov 20, 2013 8:38 pm Post subject:

I managed to make something happen beyond just blanking the screen or causing a kernel panic. By including DRM_RADEON as a module and CONFIG_DRM_RADEON_UMS, booting the system, and then passing

VoidMage · Watchman Joined: 14 Oct 2006 Posts: 6196

Just pastebin your kernel config.

Dachnaz · Posted: Thu Nov 21, 2013 4:11 pm Post subject:

Current working kernel config is at http://pastebin.com/vvEM0WQX ; DRM options start around 2105.

Cheers!
EDIT: It occurred to me that the Xserve box in question may be designed for having no 'primary' output for display, and should be outputting to the secondary display. Maybe this affects the stopping of video output when radeon is loaded - I can still access the machine via ssh.