[SOLVED] Re: [patch] enhance powerd(8) to handle max temperature

Hajimu UMEMOTO ume at freebsd.org
Tue Jul 31 14:43:20 UTC 2007


>>>>> On Tue, 31 Jul 2007 12:44:06 +0200
>>>>> Pietro Cerutti <gahr at gahr.ch> said:

gahr> Nevermind, I finally got my passive cooling working.


gahr> I don't know if the values of _TC1, _TC2 and TSP are meaningful, but it
gahr> seems to work for me, having a _PSV value of 65C.
gahr> Any suggestions on those values are welcome.

The cpufreq is controlled according to the following formula:

	P [%] = _TC1 * ( Tn - Tn-1 ) + _TC2 * ( Tn - _PSV )
	Pn = Pn-1 + HW[ - P ] where 0% <= Pn <= 100%

And, this evaluation is examined every _TSP / 10 second.
I'm not sure which values are appropriate for your box, but my laptop
has the following values:

	Name (_TC1, Zero)
	Name (_TC2, 0x0C)
	Name (_TSP, 0x28)

The values are same as you chose.
Please refer the following document for detail:



Hajimu UMEMOTO @ Internet Mutual Aid Society Yokohama, Japan
ume at mahoroba.org  ume@{,jp.}FreeBSD.org

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