Re: [PATCH] e_powersaver: Underclock checks

From: Dave Jones
Date: Wed Jul 13 2011 - 12:45:42 EST


On Wed, Jul 13, 2011 at 05:40:22PM +0100, RafaÅ Bilski wrote:
>
> >Some systems are using 1.2GHz@844mV processors running at 600MHz@796mV.
> OK. That's strange. It is 1,2GHz system. Can both ACPI p-states and "e_powersaver"
> drivers be running at the same time?

no

> Can BIOS change processor frequencies without
> Linux knowing and without p-states driver loaded?

yes. Usually via SMI. some laptops do this when switching between power/battery,
and/or when overheating.

cpufreq usually detects when this happens and logs messages.

Dave

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