[ltp] cpu frequency scaling governor "ondemand" on ThinkPad T23

[FeRD]

Robert Svoboda wrote:

>* Martin Steigerwald <Martin@lichtvoll.de> [2005-07-16 12:20]:
>
>>root@deepdance:/sys/devices/system/cpu/cpu0/cpufreq -> 
>>  cat scaling_available_frequencies
>>1130500 731500
>>    
>>
>  ^^^^^^^^^^^^^^
>  these numbers look strange (might be due to your setup),
>  mine look like this:
>
># cat scaling_available_frequencies
>600000 800000 1000000 1200000 1400000 
>
>I have ondemand governor compiled in kernel, not as module,
>that's the only difference I can see.
>
I think you're just seeing a difference in Frequency Scaling support 
between your model of ThinkPad and older units -- my T22 (1.0GHz P3) 
gives "available_frequencies' as 1000000 and 700000, which is equivalent 
to what Martin's seeing. Seems scaling was simply less robust/flexible 
in the T2x series. :(

(If I'm wrong and anyone knows how to convince a T2x ThinkPad to scale 
to anything other than 70% using cpufreq, please tell us how!) *grin*

-FeRD

P.S> Note that ACPI throttling supports the full range from 100% down to 
12%, but throttling isn't meant to be a demand-based, realtime thing. 
Tho I did find it helps keep my machine from turning into a 
thermonuclear device to have an ACPI lid-switch action set the throttle 
down a bit below 100% whenever I close the lid with the system running. :)