RE: cpufreq not working on AMD K8 (was Re: 2.6.19-rc1: known regressions)

Langsdorf, Mark
2006-10-10T16:43:24Z

> Am Dienstag, 10. Oktober 2006 16:59 schrieb Langsdorf, Mark:
> > > I have an AMD K8 system and I'm unable to get cpufreq working
> > > with 2.6.19-rc1.
> > > The cpufreq sysfs directory is missing under
> > > /sys/devices/system/cpu/cpu0/.
> > > 2.6.18 works as expected.
> >
> > What error message are you getting from `dmesg | grep power` ?
>
> dmesg | grep power
> [ 17.852383] powernow-k8: Found 2 AMD Athlon(tm) 64 X2 Dual
> Core Processor
> 3800+ processors (version 2.00.00)
> [ 17.852403] powernow-k8: MP systems not supported by PSB
> BIOS structure
> [ 17.852428] powernow-k8: MP systems not supported by PSB
> BIOS structure
>
> Haven't seen this before.

I thought I cleaned that message out in v2.0.

The BIOS failed to supply _PSS objects that Linux could
recognize. The powernow-k8 driver tried to use a PSB
table, but MP/dual-core systems can't use PSB tables.
The driver errored out.

If you can get it to work with 2.6.18 and it doesn't work
with 2.6.19-rc1, the most likely culprit is a change in the
ACPI subsystem.

Can you get decompiled dumps of the DSDT? See the ACPI
pages on sourceforge if you need instructions.

-Mark Langsdorf
AMD, Inc.