Re: Speedstep centrino

Re: Speedstep centrino

[Jeremy Fitzhardinge]

David Tunkrans wrote:
> I found your email adress in the speedstep centrino kernel source. Ive
> put down a lot of time into getting ACPI and speedstep working on my
> Mac Pro Ubuntu amd64 installation, with no success. Seems like the
> cpufreq parameters are "missing" even though the specification says
> that woodcrest Xeons do support speedstep. Also I suspect that there
> has to be specific support for Xeon processors in this driver? I would
> really appreciate if you could point me in the right direction.

In general, the newer CPUs require ACPI support to get the right
operating point parameters for the CPU; only the older Banias Pentium
M's have support built directly into the driver.  I don't know if Mac
Pros have ACPI; perhaps there needs to be some other way of getting that
info out of the BIOS, assuming its there at all.

    J

RE: Speedstep centrino

[Pallipadi, Venkatesh]

 

>-----Original Message-----
>From: cpufreq-bounces@lists.linux.org.uk 
>[mailto:cpufreq-bounces@lists.linux.org.uk] On Behalf Of 
>Jeremy Fitzhardinge
>Sent: Friday, February 02, 2007 1:26 PM
>To: David Tunkrans
>Cc: cpufreq@lists.linux.org.uk
>Subject: Re: Speedstep centrino
>
>David Tunkrans wrote:
>> I found your email adress in the speedstep centrino kernel 
>source. Ive
>> put down a lot of time into getting ACPI and speedstep working on my
>> Mac Pro Ubuntu amd64 installation, with no success. Seems like the
>> cpufreq parameters are "missing" even though the specification says
>> that woodcrest Xeons do support speedstep. Also I suspect that there
>> has to be specific support for Xeon processors in this 
>driver? I would
>> really appreciate if you could point me in the right direction.
>
>In general, the newer CPUs require ACPI support to get the right
>operating point parameters for the CPU; only the older Banias Pentium
>M's have support built directly into the driver.  I don't know if Mac
>Pros have ACPI; perhaps there needs to be some other way of 
>getting that
>info out of the BIOS, assuming its there at all.
>

Can you try acpi-cpufreq driver instead. If that doesn't work, probably
BIOS is not exporting needed ACPI information to support speedstep. We
will have to look at acpidump and see the BIOS ACPI information.

Thanks,
Venki

RE: Speedstep centrino

[Pallipadi, Venkatesh]

 
Most probably BIOS is not exporting frequency information then. I have
opened a bugzilla to make sure that this does not go untracked
(http://bugme.osdl.org/show_bug.cgi?id=7954). We need to have a look at
acpidump disassembly to be sure. Will do that soon.
 
In the mean time, can you make sure you have the latest BIOS. 
 
Thanks,
Venki


________________________________

	From: David Tunkrans [mailto:david.tunkrans@gmail.com] 
	Sent: Monday, February 05, 2007 2:38 AM
	To: Pallipadi, Venkatesh
	Cc: Jeremy Fitzhardinge; cpufreq@lists.linux.org.uk
	Subject: Re: Speedstep centrino
	
	
	Hi,
	 
	I have tried the acpi-cpufreq driver, no difference there. I
have read that some people have gotten the speedstep-centrino driver
working under 32-bit ubunto, however Im using the amd64 ubunto distro
and cant verify that. Also Im on my fourth custom kernel, testing
different config:s ( 2.6.19.1). Attached is the acpidump + dmesg from my
Mac Pro. If there is any more information that I can provide you with,
please let me know.
	 
	Thanks,
	 
	David


	 
	On 2/2/07, Pallipadi, Venkatesh <venkatesh.pallipadi@intel.com>
wrote: 



		>-----Original Message-----
		>From: cpufreq-bounces@lists.linux.org.uk 
		>[mailto:cpufreq-bounces@lists.linux.org.uk] On Behalf
Of
		>Jeremy Fitzhardinge
		>Sent: Friday, February 02, 2007 1:26 PM
		>To: David Tunkrans 
		>Cc: cpufreq@lists.linux.org.uk
		>Subject: Re: Speedstep centrino
		>
		>David Tunkrans wrote:
		>> I found your email adress in the speedstep centrino
kernel 
		>source. Ive
		>> put down a lot of time into getting ACPI and
speedstep working on my
		>> Mac Pro Ubuntu amd64 installation, with no success.
Seems like the
		>> cpufreq parameters are "missing" even though the
specification says 
		>> that woodcrest Xeons do support speedstep. Also I
suspect that there
		>> has to be specific support for Xeon processors in
this
		>driver? I would
		>> really appreciate if you could point me in the right
direction. 
		>
		>In general, the newer CPUs require ACPI support to get
the right
		>operating point parameters for the CPU; only the older
Banias Pentium
		>M's have support built directly into the driver.  I
don't know if Mac 
		>Pros have ACPI; perhaps there needs to be some other
way of
		>getting that
		>info out of the BIOS, assuming its there at all.
		>
		
		Can you try acpi-cpufreq driver instead. If that doesn't
work, probably 
		BIOS is not exporting needed ACPI information to support
speedstep. We
		will have to look at acpidump and see the BIOS ACPI
information.
		
		Thanks,
		Venki