From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTP id D3B8B679F8 for ; Wed, 17 May 2006 08:07:35 +1000 (EST) Subject: Re: ppc32 kernel boot problem (pmu related?) From: Benjamin Herrenschmidt To: Nathan Pilatzke In-Reply-To: <98889dd30605160804i78fc6a31w5147aba1dc5562b@mail.gmail.com> References: <98889dd30605111207g6afe6158je681717ccacb9e40@mail.gmail.com> <1147403525.7343.19.camel@localhost.localdomain> <98889dd30605120540n214800fbk8899fe9e39e972cf@mail.gmail.com> <1147658309.21291.73.camel@localhost.localdomain> <98889dd30605152106m9090ba3ga1a4c7706aace3ef@mail.gmail.com> <1147754594.13588.17.camel@localhost.localdomain> <98889dd30605160804i78fc6a31w5147aba1dc5562b@mail.gmail.com> Content-Type: text/plain Date: Wed, 17 May 2006 08:07:27 +1000 Message-Id: <1147817247.6753.10.camel@localhost.localdomain> Mime-Version: 1.0 Cc: linuxppc-dev@ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Tue, 2006-05-16 at 11:04 -0400, Nathan Pilatzke wrote: > On 5/16/06, Benjamin Herrenschmidt wrote: > > > > Can you try editing arch/powerpc/platforms/powermac/low_i2c.c, in > > function pmac_i2c_init(), comment out the call to pmac_i2c_devscan() and > > tell me if that makes a difference. > > > > Thanks, > > Ben. > > > > > Commenting out the call to pmac_i2c_devscan() in function > pmac_i2c_init() allowed the kernel to boot. I am typing this email > booted under it. The kernel messages were printed a bit strangely > though. There was no scrolling or clearing of the screen. The kernel > messages would start at the top and overwrite old messages, with the > cursor jumping back to the top of the screen every so often. That's because of the change you did to udbg.c for debugging :) > The /proc/device-tree is attached for the booting 2.6.17-rc3 kernel with > pmu enabled, as is the new dmesg output. If you need the > /proc/device-tree from a 2.6.15 working kernel with pmu enabled > instead, let me know. No, it should be the same regardless of the kernel > Is this kernel fairly safe/stable to use? What can be done next? Well, I need to figure out what's going on with the i2c stuff... there is a chip that hangs off the PMU and that says something like "do that at boot"... but when I do it, it causes the crash you are seeing. So either I'm not doing what it tells me to do properly or I should just blacklist this machine (Apple doesn't execute the platform functions from the device-tree on older machines I think). I'm investigating, will come back to you. Ben.