915gm/945gm/XAA lockup with gray blocks when switching video mode
pcjc2 at cam.ac.uk
Sat Oct 13 11:51:12 PDT 2007
On Sat, 2007-10-13 at 17:14 +0800, Keith Packard wrote:
> On Fri, 2007-10-12 at 05:58 -0700, Jesse Barnes wrote:
> > The latter might be due to the associated pipe being off,
> > which would disable the registers, possibly causing a GPU crash when
> > you wrote them (the fact that your crashes go away 100% points to this
> > possibility).
> Yeah, the docs say we're not supposed to write the palette when the pipe
> is off.
> I think turning the pipe on to save and restore the palette is a
> reasonable idea; it's not that hard as we don't need any plane connected
> to the pipe, just to have the clock running. That should just be a few
> register writes.
There is a user on the Ubuntu bugzilla who's still seeing a similar
crash, apparently with my patch which helps many other people who see
it. Its _probably_ not the same crash (i've not the HW to test it),
however rebooting without going through power off seems to make a
difference. (It doesn't crash after a reboot, but does if you power on
The logs are attachment:
Shutdown seems to work always, reboot mostly but switching to a console
crashes my system nearly every time (HP compaq nx5000 with 855GM
Don't know if it is a coincidence - but everything seem to work (incl.
console switching) every time I did a successful reboot from within
GNOME (without powering off the machine)!?
The only differences I note in the logs, is that dri fires up right
away, not needing to load the i915 kernel module in the log he's
provided after a reboot (which perhaps means its not the first X server
after the reboot?), and that the RENCLK_GATE_D1 register starts at '1'.
Either it survived the reboot, or again, the log is not from the first X
server after the boot.
Any ideas what parts of the HW restore routine might crash on a 855
aside from the Palette? (Assuming a similar failure mode for now).
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