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SubjectRe: [PATCH][RFC] Re: cpufreq: allow user to specify voltage

> Here's my suggestion, (partly) based on something Patrick Mochel suggested
> for the passing of attribute files of cpufreq drivers to the cpufreq core:
> a NULL-terminated list of device_attributes *attr is passed to the core. And
> if attr itself is NULL, no attribute is passed, of course. Using this
> approach, this patch against cpufreq-CVS-HEAD adds a file
> /sys/devices/sys/cpu0/scaling_available_freqs (something Carl Thompson
> asked for)
> for the powernow-k7.c and the p4-clockmod.c drivers (other frequency table
> based drivers can be added at will -- Carl, please don't realy _solely_ on
> this file: some drivers don't use frequency tables but still might want to
> use your great userspace scaling program!)
> And for powernow-k7.c , the file
> /sys/devices/sys/cpu0/scaling_setvoltage
> should show the current voltage for the current speed (scaling_setspeed).
> "echoing" a different value (must be lower than the current voltage) changes
> the voltage for this frequency only. However, this override is "static" so
> that if you switch to a different frequency in the meantime but get back to
> the one you wanted to override the voltage setting for, the new
> user-specified value is remembered.
> This is untested (don't have a powernow-k7-capable notebook), so handle with
> care.

It seems to work. I'll crash my machine now (and go to sleep ;-). So
if you don't get another mail within 30 minutes of this, it worked.

When do you have a heart between your knees?
[Johanka's followup: and *two* hearts?]
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