Re: SMU support for PowerMac G5 11,2

[David Brownlee <abs%netbsd.org@localhost>]

On 10 July 2013 13:06, Phileas Fogg <phileas-fogg%mail.ru@localhost> wrote:
>

> Quastion:
> ----------
> I'm not very familiar with envsys but is it possible to
> make it control fan speed automatically depending on the current temperature
> ? Or is it better to control fan speed in the kernel space, like
> Linux or FreeBSD kernels do it. I would appreciate any pointers here.
> Currently i'm doing it with a shell script which runs periodically.
> One odd thing i noticed is that if i set e.g. all fan speeds to 1500
> but then do not read fan rpm back for a while, SMU automatically increases
> all fan speeds. If i read fan rpms periodically then it remains
> at the speed which i configured last. Very odd.

Could this be a watchdog like feature - so if the OS hangs and stops
reading the fan speeds it will automatically fail over to running them
at full speed? Sounds like quite a nice safely feature if it is....