Re: [PATCH 1/2] CPUFREQ: Enable acpi-cpufreq driver forVIA/Centaur CPUs

From: Matthew Garrett
Date: Mon Jun 08 2009 - 10:58:33 EST

On Mon, Jun 08, 2009 at 09:25:09AM -0500, Michael S. Zick wrote:
> On Mon June 8 2009, Harald Welte wrote:
> > The VIA/Centaur C7, C7-M and Nano CPU's all support ACPI based cpu p-states
> > using a MSR interface. The Linux driver just never made use of it, since in
> > addition to the check for the EST flag it also checked if the vendor is Intel.
> >
> It looks like we should modify (conditional on ...MVIAC7 at build, model='d' runtime)
> the acpi-cpufreq controls to deal properly with the Model-D adaptive controller.

Can't make it build-time dependent - distribution kernels may not
explicitly support the C7. It's valid to have a vendor=centaur
conditional that turns off any adaptive control if appropriate ACPI
methods are present.

Matthew Garrett | mjg59@xxxxxxxxxxxxx
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