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Re: How does one control fans?



Koen Vermeer said...
> On Thu, 2005-10-13 at 18:52 +0100, marc wrote:
> 
> > I have a handle on 'governors', including those in the kernel, now. 
> > However, after I modprobe the kernel governors, nothing appears in 
> > /sys/devices/system/cpu/cpu0/ until I modprobe acpi_cpufreq.
> > Is this correct? Is there another way to activate 
> > /sys/devices/system/cpu/cpu0/cpufreq without loading this module and its 
> > 'performance' governor?
> 
> You need a cpufreq governor, and a cpufreq processor driver.
> acpi_cpufreq is a cpufreq processor driver, but not the optimal one.
> Once you've got this loaded, or any other processor driver, then you
> should be able to load any governor you want.

You mention that acpi_cpufreq is not optimal, what are the alternatives?
 
> > Yes, CONFIG_ACPI_THERMAL is set to m. There are no references to thermal 
> > in the ACPI messages :-( The thermal module is loaded.
> > # acpi -V says, 
> > No support for device type: thermal
> > AC adaper: on-line
> > So, I guess that thermal detection is not possible, unless there is 
> > something else that needs to be done. Clearly, there is thermal 
> > detection in operation, and it seems odd that it is not, apparently, 
> > under the control of ACPI.
> 
> I think it is most likely under ACPI control, but there just a
> miscommunication between the OS ACPI stuff and the BIOS ACPI stuff. I
> don't know how to debug that.

Possibly to do with the above issue. We'll see.

> > CONFIG_X86_SPEEDSTEP_CENTRINO=m
> > CONFIG_X86_SPEEDSTEP_CENTRINO_ACPI=y
> > CONFIG_X86_SPEEDSTEP_CENTRINO_TABLE=y
> 
> The last one isn't required, but I'd say it doesn't hurt either. I'm
> sorry, I think it should work, so I don't know where to look to debug
> it. You could stick to the ACPI cpufreq driver for now, just to get the
> cpufreq governor stuff going. Then, you can try to get the speedstep
> thing to work.

Indeed. Googling as I type.

-- 
Best,
Marc



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