Hard freezes of ThinkPad T41p (ATI Mobility FireGL T2)

[Valentin Schwamberger]

Hi,

whatever we have already tried yet, my T41p keeps to hard freeze (no
sysrqs, network, serial connection). So far we have tried an endless
number of xorg.conf options, several linux kernel versions, kernel
options, etc.

As you can see from the subject it's an T41p with an ATI Mobility FireGL
T2 video card. The special setup, however, is the usage of a port
replicator (IBM portreplicator II) and its DVI output. As far as I can
tell, the system seems to run stable when I only use the local flat
panel (not absolutely sure, though). I also don't use it much, but it
also seems to be stable in windows.
Now the funny part is it sometime works stable for hours (once the
desktop was properly started it runs forever). But very often after
system start up, either the display doesn't come up and stays black (I
then have to switch to console and back to X and then it suddenly
works). This problem does more often happen, when the LID is closed.
The worst problems are the hard freezes, X is already started, login to
gdm was successful and the desktop is started, mostly at the end of
gnome initialization the hard freeze occurs.
The hardfreezes also happen on switching outputs with xrandr between
LVDS and DVI or after suspend to ram or on switching to the console
(required due to the other problem above).

Here a list of config-options we have tried already

- usage of fbdev instead of radeon
- disabled mtrr (in X and in kernel)
- reduced video memory
- gartsize set to zero
- disabled dri
- usage of exa
- many versions of current git (some versions (especially those from
December) seem to work more stable then the other)

No the voodoo stuff, sometimes the problem occurs on each and ever
system start up. No way to work with the system. I then figured out that
after loading bios setup defaults, it suddenly works. But how can bios
defaults affect the behaviour of X? Especially when its  actually always
at the very same defaults?

You may find dmesg and xorg logs, xorg.conf at
http://www.pci.uni-heidelberg.de/tc/usr/bernd/downloads/xorg_t41p/

You can see options we have tried from commented lines in the xorg.conf.
Also, once the desktop was properly loaded, dri works stable after
setting to agp-mode 1.

Here's also mtrr output:

valentin at t41p:~$ cat /proc/mtrr
reg00: base=0x00000000 (   0MB), size=1024MB: write-back, count=1
reg01: base=0x3ff80000 (1023MB), size= 512KB: uncachable, count=1
reg02: base=0xd0000000 (3328MB), size= 256MB: write-combining, count=1
reg03: base=0xe0000000 (3584MB), size= 128MB: write-combining, count=1

Since it's hard freezing it's also hard to debug. Running X in gdb IMHO
doesn't make much sense, when the last command would never be seen in gdb.

Any help would be highly appreciated!

Thanks in advance,
Valentin