Re: Possible problem with ACPI

[Bruno Ducrot <ducrot@poupinou.org>]

Hi (I was off-line, sorry),

On Mon, Sep 13, 2004 at 05:07:30PM +0200, Frans Pop wrote:
> Hello Bruno,
> 
> I saw your post to d-laptop in response to astryx last week, and I have a 
> similar problem. I hope you don't mind me mailing you this way.
> 
..

> fjp@strider:/sys/devices/system/cpu/cpu0/cpufreq$ cat 
> scaling_available_frequencies
> 349991 699982 1049973 1399965 1749956 2099947 2449938 2799930
> 
> But during boot I also get (from /var/log/kern.log):
> kernel: p4-clockmod: P4/Xeon(TM) CPU On-Demand Clock Modulation available
> kernel: p4-clockmod: Warning: Pentium 4-M detected. The speedstep-ich or 
> acpi cpufreq modules offer voltage scaling in addition of frequency 
> scaling. You should use either one instead of p4-clockmod, if possible.
> 
> However, the 'speedstep-ich' module only gives me:
> $ cat scaling_driver
> speedstep-ich
> $ cat scaling_governor
> userspace
> $ cat scaling_available_frequencies
> 2799930 1599960

a P4M have only 2 frequency/voltage settings via speedstep.
Throttling is another technique to lower the frequency (somehow) but
voltage won't change, so power saving is not actually a win especially
if the ACPI idle loop take place.

> And if I use the 'acpi' module I get:
> $ cat scaling_driver
> acpi-cpufreq
> $ cat scaling_governor
> userspace
> $ cat scaling_available_frequencies
> 2800000 1600000 65535000 65535000 65535000 65535000 65535000 65535000 
> 65535000 65535000 65535000 65535000 65535000 65535000 65535000

Funny bug..  I think it's already fixed, but well, I should check this
though.

> So, the only driver that gives me a nice range of frequencies is 
> p4-clockmod.

But is not so usefull for power saving (though it may be helpfull in
case of passive cooling).

> I'm having another problem, which is that linux ACPI doesn't seem to 
> recognize my fan properly. The state is always off, even if I can clearly 
> hear the fan running. (Not sure if this is related.)
> /proc/acpi/fan/FAN$ cat state
> status:                  off
> 

For that one, I need a dump of the acpi tables.

Cheers,

-- 
Bruno Ducrot

--  Which is worse:  ignorance or apathy?
--  Don't know.  Don't care.