[mythtv-users] Epia 3d drm drivers - SOLVED

[Robin Gilks]

> On Sun, 23 Oct 2005 13:58:49 +1300 (NZDT), Robin Gilks wrote:
>
>>Greetings
>>
>>I've been using Ivors Unichrome snapshots for a while and not had any
>>problem with the dri drivers.
>>
>>I thought I'd give 2.6.13 a try as I thought that via drm was now
>>supported. The modules compile & install OK but I don't get the devices
>>created under /dev with the kernel version - what am I missing?
>>
>>Running Gentoo with udev if that makes any difference...
>>
>
> Running Fedora 4 and have the same problem using an Epia xorg rpm from
> http://washington.kelkoo.net with 2.6.13-1.1524FC4.
>
> I think that it is not a problem with the rpm. I found the udev
> development page and I noted that the change log had a line about turning
> *off* creation of /dev/dri entries (dated about March 2005).
>
> And in my case, xorg.0.log shows that there is no /dev/dri/cardx (where x
> is 0-254) and thereupon dri fails and drm is turned off.
> I note that dmesg implies that dri is properly loaded... it does not
> report the failure apparently.
>
> So now the trick is to figure out how to create a udev rule which will
> create the /dri/cardx entries....
>
> Or step back to the unichrome snaps, instead of the kernel versions,
> although that might not actually fix the problem, which appears to be
> udev..
>
> Any takers...because I am waaaaayyyy past my depth already!

Turns out that its due to the kernel DRM not recognising the PCI id of the
SP13000 video adapter. The Ivor Unichrome snapshot is much more up-to-date
and hence doesn't suffer this problem. Compare
usr/src/linux{xx}/drivers/char/drm/drm_pciids.h
and
usr/src/unichrome{xx}/drm/linux-core/drm_pciids.h

Guess we'll have to wait for a kernel update and use the snapshot in the
meantime.

-- 
Robin Gilks