On 29. jan 2006, at 2.01, Brian D. Carlstrom wrote:
windfarm* is the newer set of thermal driver that will replace
therm_pm72.c someday according to Benjamin Herrenschmidt.
<snip>
Note he has a PowerMac9,1, which needs the windfarm_pm91.c driver.
I have FC4 on six PowerMacs (one PowerMac7,2 and five PowerMac7,3) and
on two of the 2.7GHz PowerMac7,3 machines I've been having overheating
problem. There is a known bug in the 2.6.14 therm_pm72.c driver, which
is patched in 2.6.15:
commit 6ee7fb7e363aa8828b3920422416707c79f39007
Author: Benjamin Herrenschmidt <benh(a)kernel.crashing.org>
Date: Mon Dec 19 11:24:53 2005 +1100
[PATCH] powerpc: g5 thermal overtemp bug
The g5 thermal control for liquid cooled machines has a small
bug, when
the temperatures gets too high, it boosts all fans to the max, but
incorrectly sets the liquids pump to the min instead of the max
speed,
thus causing the overtemp condition not to clear and the
machine to shut
down after a while. This fixes it to set the pumps to max speed
instead.
This problem might explain some of the reports of random
shutdowns that
some g5 users have been reporting in the past.
Many thanks to Marcus Rothe for spending a lot of time trying
various
patches & sending log logs before I found out that typo. Note that
overtemp handling is still not perfect and the machine might still
shutdown, that patch should reduce if not eliminate such
occcurences in
"normal" conditions with high load. I'll implement a better
handling
with proper slowing down of the CPUs later.
Signed-off-by: Benjamin Herrenschmidt <benh(a)kernel.crashing.org>
Signed-off-by: Linus Torvalds <torvalds(a)osdl.org>
However, when I switched to FC4 the updates-testing kernel to get the
patch, now my fans run full blast as if no driver is talking to the
hardware (as I saw when the PowerMac7,3 first came out and
therm_pm72.c
did not check for it). Unfortunately the machines are in production
so I
can't try FC5 at the moment, so for now I live the the noisy fans.
> What problem are you having with the fans ? are they running at full
> speed ? as root run 'modprobe therm_pm72' does that resolve the
> situation ?
This does not work for me with the recent FC4 updates-testing kernel
because the driver is not built as a module which I found odd. I
posted
on fedora-test-list and got no followups.
I just thought that I would mention that I received an e-mail from
Benjamin Herrenschmidt that contained the following:
From: benh(a)kernel.crashing.org
Oh, ok.. you mean the fans going full speed ? That's a matter of
thermal
control not working on the machine. It's the single CPU G5 names
PowerMac9,1 in /proc/device-tree/model right ?
It should indeed work with recent kernels. I got some code in
2.6.15 but
there might still have been unresolved issues. Make sure you load the
windfarm_pm91 module and let us know... If it doesn't work, try an
up to
date git snapshot. If still doesn't work, let me know and we'll track
the problem down.
This is hopefully of some help. I got this e-mail when I was trying
to get Debian to work from the Etch installer. I believe it was
Debian testing. Anyway, I don't really understand any of this. Sort
of like a Concord going over my head ;-)
Cheers,
Brian