From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753675AbYATNWZ (ORCPT ); Sun, 20 Jan 2008 08:22:25 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752672AbYATNWQ (ORCPT ); Sun, 20 Jan 2008 08:22:16 -0500 Received: from slowhand.arndnet.de ([88.198.19.76]:58809 "EHLO mail.unitix.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752458AbYATNWP (ORCPT ); Sun, 20 Jan 2008 08:22:15 -0500 Message-ID: <47934B2E.3020707@i4.informatik.rwth-aachen.de> Date: Sun, 20 Jan 2008 14:22:54 +0100 From: Arnd Hannemann User-Agent: Thunderbird 2.0.0.6 (X11/20071022) MIME-Version: 1.0 To: Jordan Crouse CC: Andres Salomon , marc.jones@amd.com, Linux Kernel Mailing List , wim@iguana.be Subject: Re: [GEODE] Geode GX/LX watchdog timer (was 2.6.24-rc8 hangs at mfgpt-timer) References: <478E4267.7020509@i4.informatik.rwth-aachen.de> <20080116161912.7b449466@ephemeral> <20080116165606.3ebc06a4@ephemeral> <478F25D6.3060503@i4.informatik.rwth-aachen.de> <20080117134032.4cc1a1cf@ephemeral> <478FB255.5040001@i4.informatik.rwth-aachen.de> <20080117211917.GF8244@cosmic.amd.com> <478FCDB6.4010708@i4.informatik.rwth-aachen.de> <20080117223644.GK8244@cosmic.amd.com> <478FDC12.6020505@i4.informatik.rwth-aachen.de> <20080119010624.GA25328@cosmic.amd.com> In-Reply-To: <20080119010624.GA25328@cosmic.amd.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Jordan Crouse wrote: > On 17/01/08 23:52 +0100, Arnd Hannemann wrote: >>>> Watchdog for the new API would be great :-) >>> Coming soon. > > As promised, a watchdog driver for the Geode GX/LX processors is attached. > I basically just ported the previous patch forward to 2.6.24. Great work! > > I also have good news or bad news depending on your perspective. I wanted > to test this against 2.6.24, and OLPC is stuck at an older kernel version, > so I had to test this with coreboot (LinuxBIOS) on another Geode > platform. Like all BIOSen execpt for the OLPC firmware, coreboot uses > VSA (SMM handler) which consumes all the timers. > > So I used the magical MSR and surprise! - the timer tick hung. > I compiled out the timer tick, and tested the watchdog timer instead, > and it worked fine on timer 0. So I don't think the MFGPTs themselves > have anything to do with this problem, but I do think it might be > related to VSA and possibly interrupts too. I'm going to invoke the > strong BIOS fu of our LinuxBIOS / BIOS expert Marc Jones, and see what > he comes up with. > > I don't know how much of a hassle it would be for Andres to get a 2.6.24 > kernel running on the OLPC to make sure that this isn't a regression > in the timer tick code (I suspect it isn't a regression, but you never > know). I also think that it would probably be in our best interest to > default CONFIG_GEODE_MFGPT_TIMER to 'n' until we get this figured > out. Since most BIOSen don't have timers available, that shouldn't affect > too many people. > > So, anyway, enjoy the watchdog timer - I hope it meets everybody's > expectations for the 2.6.25 kernel. Thanks a lot for this, it works great! (with CONFIG_GEODE_MFGPT_TIMER not set). However some minor issues: Could the name of the /dev entry perhaps be changed from "geode-watchdog" to "watchdog" instead? I think all other watchdogs use "watchdog", and using two different watchdogs in the same machine won't work anyway, because of the same minor number, right? As a second point my gcc (4.1.2) issues a warning: drivers/watchdog/geodewdt.c: In function ‘geodewdt_remove’: drivers/watchdog/geodewdt.c:256: warning: control reaches end of non-void function which I think is a valid one. > > Jordan > Best regards, Arnd