From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from vs166246.vserver.de (static-ip-62-75-166-246.inaddr.intergenia.de [62.75.166.246]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTP id B95EBDDE38 for ; Sat, 16 Jun 2007 23:06:42 +1000 (EST) From: Michael Buesch To: Benjamin Herrenschmidt Subject: Re: Powerbook hard shutdown after boot if it's hot Date: Sat, 16 Jun 2007 15:06:33 +0200 References: <200706141739.12754.mb@bu3sch.de> <1181955074.26853.105.camel@localhost.localdomain> <200706161504.41168.mb@bu3sch.de> In-Reply-To: <200706161504.41168.mb@bu3sch.de> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-15" Message-Id: <200706161506.33589.mb@bu3sch.de> Cc: linuxppc-dev@ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Saturday 16 June 2007 15:04:41 Michael Buesch wrote: > On Saturday 16 June 2007 02:51:13 Benjamin Herrenschmidt wrote: > > On Thu, 2007-06-14 at 17:39 +0200, Michael Buesch wrote: > > > Hi, > > > > > > I have a strange problem that my Powerbook shuts down hard > > > right after boot, if the machine is hot. > > > For example, if I compile a kernel and then want to reboot > > > into it, it will shutdown the machine right after userspace > > > is booted. Cooling down the machine will fix the issue. > > > I first thought this might be a problem with the adt746x > > > chip driver (thermostat). But this turns out to not be > > > the case. I disabled the module (put return 0; early into > > > the module_init function), but the problem still exists. > > > I'm not sure how to debug this, as I don't see what's > > > going on. I tried to boot with init=/bin/bash. It will > > > boot into the shell but shutdown hard after 1 or 2 seconds. > > > It seems like there is some timer hitting in right after > > > userspace is up and running (some workqueue?). Strange is > > > that it _only_ shuts down the machine when it's hot > > > and it _only_ does this right after boot. If it survived > > > the first few seconds after boot, it's rock-stable and > > > it won't show any problems when getting hot (will drive > > > the fans correctly, etc etc...) > > > > > > Any idea how to debug this? > > > > Not really, that's weird.. maybe trying to print the values in the adt > > sensor to see how hot it is vs. the various thresholds set by the > > The thresholds are the same as when the machine is cold: > 81 80 87 > > I also tried to spinup the fans at full speed on boot (by setting > the fan_speed variable in the adt driver to 255), but it kills > the machine before the fans have the ability to spin up. > > I also tried to move the 2000ms sleep in the adt monitor task down > to the bottom of the task function, so it immediately runs the task > once on boot. But that didn't help either. > > I think this powerdown is not really related to the adt chip/driver. > I think it's more likely some PMU issue and the PMU forces the machine > down. How's the PMU involved into temperatures? Does it get > the temperature values from the adt chip? > > > firmware ? Maybe the PMU is trying to send us a "high temp" alert via a > > PMU message we don't know how to parse and expcts us to reply in a given > > amount of time (for example by slowing the CPU down). > > Where in the kernel code are the PMU messages handled? > Oh, and I completely forgot to say that this problem does not exist when booting OSX. So if I try to boot linux and it fails because of the issue and I immediately boot OSX it will succeed. -- Greetings Michael.