Updated acpi_cpu patch

Lukas Ertl l.ertl at univie.ac.at
Wed Nov 26 14:14:13 PST 2003

On Wed, 26 Nov 2003, Nate Lawson wrote:

> It's possible the fan is under BIOS control so make sure you have an
> up-to-date bios.  If not, you should get a console printout when acpi
> switches the fan on.  sysctl hw.acpi.thermal

Nope, no ACPI messages, and I can't find a FAN device in my ASL. (At least
no 'standard' one - anyone knows what hides behind this HKEY device
every ThinkPad seems to have?)

> You are correct.  _PSV is not currently implemented by FreeBSD but I hope
> to do it at some point.  Once we have all methods of processor control
> (cpufreq, Cx, and throttling), we can use them to implement _PSV.  In any
> case, I think the _PSV value is set high because your platform designer
> expects active cooling to be the most effective and passive, since it
> slows down performance, is a last resort.

Ah, sounds reasonable, thanks for the explaination.


Lukas Ertl                             eMail: l.ertl at univie.ac.at
UNIX Systemadministrator               Tel.:  (+43 1) 4277-14073
Vienna University Computer Center      Fax.:  (+43 1) 4277-9140
University of Vienna                   http://mailbox.univie.ac.at/~le/

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