2007-11-13 05:25:10

by Philip Langdale

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Subject: powernow-k8 and non-standard multipliers

Hi Mark,

I've just upgraded to an X2 5000+ black edition. This model
doesn't have a multiple lock and I tried bumping the multiplier
up, which is perfectly stable, but which causes powernow-k8 to
fail to load. I also tried with the updated patch you posted
at the beginning of october (http://lkml.org/lkml/2007/10/9/224)
which didn't make a difference.

Is it possible to make the driver work in this situation or does
a non-standard multipler inherently mean that powernow stops
working?

Thanks,

--phil


2007-11-13 15:17:40

by Langsdorf, Mark

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Subject: RE: powernow-k8 and non-standard multipliers

> I've just upgraded to an X2 5000+ black edition. This model
> doesn't have a multiple lock and I tried bumping the multiplier
> up, which is perfectly stable, but which causes powernow-k8 to
> fail to load. I also tried with the updated patch you posted
> at the beginning of october (http://lkml.org/lkml/2007/10/9/224)
> which didn't make a difference.
>
> Is it possible to make the driver work in this situation or does
> a non-standard multipler inherently mean that powernow stops
> working?

The standard PowerNow! driver, by design, will stop
working in this situation. I'm not going to support
a driver that allows non-standard multipliers because
it could cause a lot of hard to debug maintenance
issues.

-Mark Langsdorf
Operating System Research Center
AMD


2007-11-15 07:54:54

by Philip Langdale

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Subject: Re: powernow-k8 and non-standard multipliers

Langsdorf, Mark wrote:
>
> The standard PowerNow! driver, by design, will stop
> working in this situation. I'm not going to support
> a driver that allows non-standard multipliers because
> it could cause a lot of hard to debug maintenance
> issues.

Just a follow-up to get this into the public record. I
discussed this with Mark privately and then did more
digging and established that in my particular case, the
problem was that the BIOS was hiding the p-state table
when a non-standard multiplier was used. So, I built
a custom DSDT that included the p-state table along
with an extra entry for my higher speed and now I've
happily got powernow support again.

--phil