On Fri, 2006-08-18 at 00:39 +0300, ext Pavel Machek wrote:
> Hi!
>
> > > If there are dependancies inherently linking core1 and core2,
> cpufreq
> > > should already be programming both parts. For example, the SA1100
> > > driver programs both CPU and SDRAM controller. If there isn't any
> > > dependancy
> > > between them, I don't see the attraction of creating an artificial
> one
> > > in the way suggested for no real purpose.
> > >
> > > Things like voltage and frequency are closely tied together, so
> > > offering
> > > any means of controlling them independantly makes no sense afaics.
>
> > Yet a certain subsystem (for example an onboard camera, in a phone)
> > might require a higher voltage when it's active, effectively
> loosening
> > the tight coupling between freq and voltage that the porcessor is
> > enforcing.
>
> So... you expect userland to echo high > state before camera can be
> used?
>
> I'd rather have kernel automagically up the voltage when /dev/video0
> is opened...
Not really, I meant that the CPU is not the only customer of power
domains (depend on the HW design), so the relation freq <-> voltage is
not always true.
--
Cheers,
Igor
Igor Stoppa (Nokia M - OSSO / Tampere)
