[PlanetCCRMA] Laptop Power Management - cpufreq

Fernando Pablo Lopez-Lezcano nando@ccrma.Stanford.EDU
Wed Apr 28 02:49:02 2004


> I'm running FC1 and kernel 2.4.24-1.ll.rhfc1.ccrma on a Thinkpad T23 laptop 
> (Pentium III Mobile).  I just recently noticed that cpufreq does not work 
> and that some kernel modules don't exist with this ccrma kernel, 
> specifically speedstep-centrino, speedstep-lib, and speedstep-ich.  The 
> reason I even got so far as to figure this out is that I realized lately 
> that when doing "cat /proc/cpuinfo" that the cpu speed wasn't changing with 
> AC power or not.

Hmmm, maybe that is provided by APM? I have to investigate, don't really
know. For historical reasons the Planet CCRMA kernel starts with acpi
enabled (Fedora's kernel starts with it disabled) so you may want to
turn that off if you need APM instead. Add "acpi=off" in the kernel boot
line. 

> Is there something I'm missing and cpu frequency is controlled by some other 
> means? 

You'll find the acpi stuff in:
  /proc/acpi/*

-- Fernando