Re: [arch-general] powernow-k8 fails to load with linux 3.7.2

Tom Gundersen
2013-01-17T10:34:22Z

On Thu, Jan 17, 2013 at 10:46 AM, Borislav Petkov <bp@alien8.de> wrote:
> On Wed, Jan 16, 2013 at 06:16:00PM -0600, Leonid Isaev wrote:
>> > [ fixup Andre's address. ]
>> >
>> > On Wed, Jan 16, 2013 at 11:33:21PM +0100, Rafael J. Wysocki wrote:
>> > > > down the frequancy, but is accompanied by an info-level kernel message
>> > > > "acpi-cpufreq: overriding BIOS provided _PSD data".
>> >
>> > That just says that BIOS has crappy data and we're using our own.
>>
>> OK. Yes, my BIOS is broken, so I thought it was the reason why autoloading does
>> not work.
>
> Hmm, come to think of it, we're issuing this message on SMP on *all*
> AMDs with HW_PSTATE. Andre, remind me again why we're doing this? We're
> basically saying that we're overriding ACPI data but we still read it
> out from acpi_perf_data and use *that* data to prepare the frequencies
> table. What am I missing?
>
>> To be more precise: "modprobe powernow-k8" returns a "no such device" error,
>
> That's correct - we say ENODEV on your CPU which supports hardware
> P-states and hand off to acpi-cpufreq which has that functionality now.
>
>> but in kernel logs I see that acpi-cpufreq is indeed loaded:
>> -------
>> Jan 15 22:42:19 metal-0 kernel: [ 534.003995] acpi-cpufreq: overriding BIOS
>> provided _PSD data
>> Jan 15 22:42:32 metal-0 kernel: [ 547.122695] powernow-k8: this CPU is not
>> supported anymore, using acpi-cpufreq instead.
>> Jan 15 22:42:45 metal-0 kernel: [ 559.623068] powernow-k8: this CPU is not
>> supported anymore, using acpi-cpufreq instead.
>> -------
>> (the CPU in question is phenom II x4 955). However, this is only after I
>> attempt to _manually_ load powernow-k8 (the timestamps in [...] are ~6 mins
>> after boot is completed). So the above-mentioned handoff seems to work, but
>> please find attached my kernel config.
>
> Ok, this is maybe the issue. What used to load powernow-k8 on your
> distro before? Because basically it's enough if some script did
> 'modprobe powernow-k8' for the handoff to just work.
>
> But, we also have the CPU autoprobing deal:
>
> http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=644e9cbbe3fc032cc92d0936057e166a994dc246

Arch relies entirely on the CPU autoprobing, there are no scripts
modprobing things at boot.

> so, *actually*, powernow-k8 should be loaded by default. I dunno, maybe
> upgrade udev on your distro?

Assuming Leonid's system is up-to-date, Arch ships the most recent
udev version (197).

Cheers,

Tom