ACPI throttling changes

[John Baldwin]

On 10-Dec-2003 Nate Lawson wrote:
> I'm working on a shared CPU frequency control driver.  One step is to
> remove some of the autonomy of the throttling portion of acpi_cpu.
> Please test this patch if you have a machine which supports throttling.
> With this patch, throttling can be changed by doing:
> 
>    sysctl hw.acpi.cpu.current_speed=X
> 
> where X is some number between 1 and hw.acpi.cpu.max_speed.  It is no
> longer driven by AC line transitions.  Run a CPU benchmark like this one
> to make sure the throttling transition still works with this patch.
> 
>     dd if=/dev/zero bs=1m count=500 | md5
> 
> This is part of a larger work.  Don't worry, it won't be committed until
> general CPU frequency control is done so no loss of functionality will be
> committed.

We need to support using throttling for passive cooling btw.  My new laptop
I just got has no active cooling support, but does have _TC1 and _TC2 objects
in its thermal zone.  Are you going to add that?

-- 

John Baldwin <jhb at FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve!"  -  http://www.FreeBSD.org/