Re: [2.6.25-rc3] ACPI _PPC limiting processor speed...

Re: [2.6.25-rc3] ACPI _PPC limiting processor speed...

[Andrew Morton]

On Mon, 25 Feb 2008 21:29:24 +0000 "Daniel J Blueman" <daniel.blueman@gmail.com> wrote:

> My 2.2GHz [1] Thinkpad T61 is unable to get past 1.2GHz, seemingly
> because of the _PPC ACPI objects [2].
> 
> Given that the _PPC object is different for both cores, is this more
> of a BIOS bug or an ACPI interpreter problem? The problem was present
> in 2.6.24-rc, 2.6.24 final and since.
> 
> BIOS is 7LETA9WW/2.09, so current - would any further information be
> useful for debugging this problem, and would dumping the ACPI tables
> be useful?
> 
> Thanks,
>   Daniel
> 
> --- [1]
> 
> freq-table: table entry 0: 2201000 kHz, 0 index
> freq-table: table entry 1: 2200000 kHz, 1 index
> freq-table: table entry 2: 1600000 kHz, 2 index
> freq-table: table entry 3: 1200000 kHz, 3 index
> freq-table: table entry 4: 800000 kHz, 4 index
> 
> --- [2]
> 
> cpufreq-core: CPU 0: _PPC is 3 - frequency  limited
> cpufreq-core: CPU 1: _PPC is 0 - frequency not limited

(cc linux-acpi)

If nothing happens, please raise a report at bugzilla.kernel.org, thanks.

Re: [2.6.25-rc3] ACPI _PPC limiting processor speed...

[Daniel J Blueman]

On Mon, Feb 25, 2008 at 11:48 PM, Andrew Morton
<akpm@linux-foundation.org> wrote:
> On Mon, 25 Feb 2008 21:29:24 +0000 "Daniel J Blueman" <daniel.blueman@gmail.com> wrote:
>  > My 2.2GHz [1] Thinkpad T61 is unable to get past 1.2GHz, seemingly
>  > because of the _PPC ACPI objects [2].
>  >
>  > Given that the _PPC object is different for both cores, is this more
>  > of a BIOS bug or an ACPI interpreter problem? The problem was present
>  > in 2.6.24-rc, 2.6.24 final and since.
>  >
>  > BIOS is 7LETA9WW/2.09, so current - would any further information be
>  > useful for debugging this problem, and would dumping the ACPI tables
>  > be useful?
>  >
>  > Thanks,
>  >   Daniel
>  >
>  > --- [1]
>  >
>  > freq-table: table entry 0: 2201000 kHz, 0 index
>  > freq-table: table entry 1: 2200000 kHz, 1 index
>  > freq-table: table entry 2: 1600000 kHz, 2 index
>  > freq-table: table entry 3: 1200000 kHz, 3 index
>  > freq-table: table entry 4: 800000 kHz, 4 index
>  >
>  > --- [2]
>  >
>  > cpufreq-core: CPU 0: _PPC is 3 - frequency  limited
>  > cpufreq-core: CPU 1: _PPC is 0 - frequency not limited
>
>  (cc linux-acpi)
>
>  If nothing happens, please raise a report at bugzilla.kernel.org, thanks.

I've raised this into a Bugzilla entry for tracking and history, and
dumped ACPI tables in binary and hex formats:

http://bugzilla.kernel.org/show_bug.cgi?id=10110

Let me know of anything else useful. If I get time in the next days,
I'll try find a previous working kernel and start bisecting for the
regression.

Thanks,
  Daniel
-- 
Daniel J Blueman