Re: [QUESTION] 3 frequency steps for p3 on windows

[Simon Braunschmidt <brasimon@web.de>]

Hi again

Any ideas about this? 

At least some pointer about where to start investigating would be usefull, so 
i could start a the right place. Maybe you know off some tool to investigate 
the system state state in winxp for comparison with linux?

Greeting
Simon

Am Dienstag, 17. Mai 2005 17:11 schrieb Simon Braunschmidt:
> Am Donnerstag, 12. Mai 2005 22:53 schrieb Simon Braunschmidt:
> > Hi,
> >
> > I have a compaq armada m300 with a speedstep-enabled 600mhz pentium.
> > It is running ubuntu so its essentialy a 2.6.10 kernel.
> > Scaling the frequency dynamically works very good so far, i can choose
> > between ~500mhz and ~600mhz.
> >
> > However, when i boot into windows xp sp2, after installing some enabler
> > programm from the compaq website, the freqency of the cpu is scaled
> > dynamically with the THREE steps  ~413mhz, ~500mhz and ~600mhz, the exact
> > values for 500 and 600 being the same as in linux.
> >
> > So in windows i get an extra frequency option for 413mhz not available in
> > linux.
> >
> > Is there any chance of supporting this in linux? Since i only ever heard
> > of 2 frequency steps for the early p3's, i think this will be a
> > compaq-specific behaviour. Is compaq giving out documentation?
> >
> > please cc me
> >
> > Greetings
> > Simon Braunschmidt
>
> After some (random) experimentation (changing from ac to battery while in
> s3 state, maybe something more, didnt take notes, seems all unrelated), the
> frequency steping in linux was ~415mhz and ~500mhz. The values
> in /sys­­/.../cpufreq stayed the same, and the max. frequency was now
> ~500mhz (the 600mhz diddnt seem to work anymore).
>
> This behaviour was gone after a reboot and i hadnt been able to reproduce
> it, strange.
>
> So in principle it is possible under linux to use the "compaq 3 steps
> behaviour", but the inner workings need to be understood. Any pointers
> where i could start?
>
> Greetings
> Simon Braunschmidt
>
> > simon@heimdal:/sys/devices/system/cpu/cpu0/cpufreq$ uname -a
> > Linux heimdal 2.6.10-5-686 #1 Tue Apr 5 12:27:02 UTC 2005 i686 GNU/Linux
> >
> > simon@heimdal:/sys/devices/system/cpu/cpu0/cpufreq$ cat /proc/cpuinfo
> > processor       : 0
> > vendor_id       : GenuineIntel
> > cpu family      : 6
> > model           : 8
> > model name      : Pentium III (Coppermine)
> > stepping        : 3
> > cpu MHz         : 498.115
> > cache size      : 256 KB
> > fdiv_bug        : no
> > hlt_bug         : no
> > f00f_bug        : no
> > coma_bug        : no
> > fpu             : yes
> > fpu_exception   : yes
> > cpuid level     : 2
> > wp              : yes
> > flags           : fpu vme de pse tsc msr pae mce cx8 sep mtrr pge mca
> > cmov pat pse36 mmx fxsr sse
> > bogomips        : 986.45
> >
> > simon@heimdal:/sys/devices/system/cpu/cpu0/cpufreq$ sudo cat *
> > Password:
> > 0
> > 500000
> > 600000
> > 500000
> > 600000 500000
> > userspace ondemand powersave performance
> > 500000
> > speedstep-smi
> > userspace
> > 600000
> > 500000
> > 500000
> > simon@heimdal:/sys/devices/system/cpu/cpu0/cpufreq$