How to disable acpi thermal?

[Alexandre "Sunny" Kovalenko]

On Wed, 2008-02-20 at 18:48 -0500, Daniel Eischen wrote:
> On Wed, 20 Feb 2008, Alexandre \Sunny\ Kovalenko wrote:
> 
> >
> > On Wed, 2008-02-20 at 17:15 -0500, Daniel Eischen wrote:
> >> On Fri, 15 Feb 2008, Alexandre "Sunny" Kovalenko wrote:
> >>
> >>>
> >>> On Tue, 2008-01-15 at 15:34 -0500, Daniel Eischen wrote:
> >>>> [ Redirected from -current ]
> >>>>
> >>>> I posted the acpidump here:
> >>>>
> >>>>    http://people.freebsd.org/~deischen/stl2.iasl
> >>>>
> >>>> The problem is that acpi_thermal keeps shutting down the system
> >>>> after 2 minutes into a buildkernel.  The system has no load other
> >>>> than the buildkernel at the time it shuts down.
> >>>>
> >>>> The system is a Intel STL2 Tupelo motherboard with 1 CPU, the
> >>>> other CPU socket being occupied by a CPU terminator thingy.
> >>>> I uncovered the rackmount system and watched it while building
> >>>> a kernel.  With the cover off the acpi monitored temperature
> >>>> went to 107C and stayed there.  It only took a minute or two
> >>>> to get there.  I felt around inside the chassis and nothing
> >>>> was even near being to warm or hot.  With the cover on, the
> >>>> temperature goes to 111/112C before being shutdown by acpi_thermal
> >>>> (the limit being 110C).  There is no way anything in that
> >>>> chassis is anywhere near 100C.  I've disabled acpi_thermal
> >>>> for now, but it'd be nice to get a better fix.
> >>>>
> >>>> Any ideas?
> >>>>
> >>> You can try this patch on your ASL, which might just cause passive
> >>> cooling to kick in. If you decide to try a patch, I would like to see
> >>> the output of
> >>
> >> I guess I'm confused - how can passive cooling "kick in".  Isn't
> >> passive cooling always on if you are using a heatsink?
> > In the ACPI context (and please, bear with me -- I am no expert -- I
> > just read respective pieces of the spec and experimented with few
> > specimens of my own hardware) "passive" cooling is lowering of the CPU
> > frequency when temperature reaches given point, as denoted by
> > hw.acpi.thermal.tzN._PSV value. This will happen (I have tried ;)
> > regardless of the efforts of powerd to raise the frequency due to the
> > load history. This helps in the situations when CPU could not run at
> > maximum load for protracted periods of time.
> 
> Ok, now this makes sense.
> 
> > I assume (possibly incorrectly) that 1) your CPU is capable of the
> > frequency throttling and 2) you are using frequency governor of some
> > sort (see cpufreq(4) for detail). If this is not the case, the change
> > will not help.
> 
> I don't know about 1):
> 
>    CPU: Intel Pentium III (933.08-MHz 686-class CPU)
>    Origin = "GenuineIntel"  Id = 0x686  Stepping = 6
>    Features=0x383fbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,MMX,FXSR,SSE>
> 
> and 2), no, I'm not using a frequency governor from what I can
> tell.
> 
>    $ sysctl -a | grep dev.cpu
>    dev.cpu.0.%desc: ACPI CPU
>    dev.cpu.0.%driver: cpu
>    dev.cpu.0.%location: handle=\_PR_.CPU0
>    dev.cpu.0.%pnpinfo: _HID=none _UID=0
>    dev.cpu.0.%parent: acpi0
>    dev.cpu.0.cx_supported: C1/0
>    dev.cpu.0.cx_lowest: C1
>    dev.cpu.0.cx_usage: 100.00%
> 
>    $ sudo kldload /boot/kernel/cpufreq.ko
> 
>    $ sysctl -a | grep dev.cpu
>    dev.cpu.0.%desc: ACPI CPU
>    dev.cpu.0.%driver: cpu
>    dev.cpu.0.%location: handle=\_PR_.CPU0
>    dev.cpu.0.%pnpinfo: _HID=none _UID=0
>    dev.cpu.0.%parent: acpi0
>    dev.cpu.0.cx_supported: C1/0
>    dev.cpu.0.cx_lowest: C1
>    dev.cpu.0.cx_usage: 100.00%
> 
> 
> > Also, since I have sent you that change, I have learned that setting
> > hw.acpi.thermal.user_override=1 and hw.acpi.thermal.tz0._PSV=85C might
> > accomplish the same thing as the ASL change. I saw it working for the
> > thermal zone which already had sensible _PSV, but I have no hardware to
> > try this approach when _PSV is not present in the ASL.
> 
> Well, this is a server board, not a laptop, so I'm not sure
> it even has CPU throttling.
> 
As far as I can tell from the stuff above -- it does not. I was confused
by presence of some pieces in the ASL, which would normally indicate
that it does. One thing, which surprises me, is that with the lack of
throttling and, what appears to be single speed fan or even a heatsink,
I do not see how its thermal mode could behave differently in the
presence of the load. Could you, please, send me output of the sysctl
machdep.

-- 
Alexandre "Sunny" Kovalenko (Олександр Коваленко)