[issue1359] PowerNow! support

[YONETANI Tomokazu]

On Sun, May 10, 2009 at 10:30:39PM +0200, Sascha Wildner wrote:
> Alexander Polakov (via DragonFly issue tracker) schrieb:
>> I made some changes, don't know if it helps, but debugging should be easier.
>> Sorry, I don't have any experience in writing kernel drivers.
>
> But another thing: As you are the only person so far for whom this patch  
> works, can you check out if it works OK with sysutils/estd from pkgsrc,  
> which seems to support the machdep.powernow sysctls.

It seems to work for me, although it's not a laptop PC
(Athlon 64 X2 4400+ and a cheap mainboard from ASRock).

$ sysctl machdep.powernow
machdep.powernow.frequency.current: 1800
machdep.powernow.frequency.available: 2200 2000 1800 1000
$ estd -oa
estd: Not detaching from terminal
1000 MHz

and it prints a new frequency as the load average changes (and of course
machdep.powernow.frequency.current changes to that value).  Apparently
get_cpuusage() in estd returns half the value of actual load average when
run on SMP, so the low-water and high-water values should be tweaked for it
to work correctly.

Thanks.