Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753916AbYAVSQz (ORCPT ); Tue, 22 Jan 2008 13:16:55 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751890AbYAVSQq (ORCPT ); Tue, 22 Jan 2008 13:16:46 -0500 Received: from outbound-dub.frontbridge.com ([213.199.154.16]:29621 "EHLO outbound6-dub-R.bigfish.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751888AbYAVSQp (ORCPT ); Tue, 22 Jan 2008 13:16:45 -0500 X-BigFish: VP X-MS-Exchange-Organization-Antispam-Report: OrigIP: 139.95.251.8;Service: EHS X-Server-Uuid: 9D002D81-0D89-4A8A-BDDE-D174997CF0D6 Date: Tue, 22 Jan 2008 11:15:42 -0700 From: "Jordan Crouse" To: "Arnd Hannemann" cc: "Lars Heete" , "Andres Salomon" , "Linux Kernel Mailing List" Subject: Re: 2.6.24-rc8 hangs at mfgpt-timer Message-ID: <20080122181542.GB5241@cosmic.amd.com> References: <20080116165606.3ebc06a4@ephemeral> <478FCDB6.4010708@i4.informatik.rwth-aachen.de> <4795B14C.7040502@i4.informatik.rwth-aachen.de> <200801221111.21240.hel@admin.de> <4795D120.7070806@i4.informatik.rwth-aachen.de> MIME-Version: 1.0 In-Reply-To: <4795D120.7070806@i4.informatik.rwth-aachen.de> User-Agent: Mutt/1.5.15+20070412 (2007-04-11) X-OriginalArrivalTime: 22 Jan 2008 18:14:29.0388 (UTC) FILETIME=[A124E4C0:01C85D22] X-WSS-ID: 6B88ED610QK8490730-13-01 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3723 Lines: 88 On 22/01/08 12:18 +0100, Arnd Hannemann wrote: > Hi Lars, > > Lars Heete schrieb: > > Hello, > > > > On Tuesday 22 January 2008 10:03:08 am Arnd Hannemann wrote: > >> Jordan Crouse wrote: > >>> Okay - I've been exploring a little bit more. I talked to the TinyBIOS > >>> developer, and he verified that TinyBIOS shouldn't use any MFGPT timers. > >>> He also told me that the mysterious "MFGPT workaround" was in fact the > >>> magic MFGPT erasing MSR that was in the old kernel driver. > >>> > >>> So with the "MFGPT workaround" turned off, TinyBIOS should be acting like > >>> the OLPC firmware with regards to timers, yet it is not. So that is > >>> curious. I think I might have identified a race condition in the code, > >>> but I'm not 100% sure thats the same problem that the ALIX platform is > >>> seeing. > >>> > >>> Anrd and others - will you please try the attached patch on your platform > >>> with the "MFGPT workaround" turned off and mfgpts enabled, and send out > >>> the dmesg? > >> Of course, tinyBios version v0.99, "MFGPT workaround" turned off, > >> CONFIG_GEODE_MFGPT_TIMER=n: > >> > >> [ 67.369697] NET: Registered protocol family 16 > >> [ 67.383059] geode-mfgpt: IRQ MSR=0:0 > >> [ 67.394058] geode-mfgpt: NMI MSR=0:0 > >> [ 67.405049] geode-mfgpt: Unrestricted sources=0 > >> [ 67.418909] geode: 8 MFGPT timers available. > >> [ 67.433211] PCI: PCI BIOS revision 2.10 entry at 0xfcd03, last bus=0 > >> > >> same with CONFIG_GEODE_MFGPT_TIMER=y (sorry, without move printk patch): > >> > >> [ 22.289349] NET: Registered protocol family 16 > >> [ 22.302716] geode-mfgpt: IRQ MSR=0:0 > >> [ 22.313716] geode-mfgpt: NMI MSR=0:0 > >> [ 22.324704] geode-mfgpt: Unrestricted sources=0 > >> [ 22.338566] geode-mfgpt: Registered timer 0 > >> [ 22.351393] mfgpt-timer: registering the MFGT timer as a clock event. > >> ^^^^ Hangs here > > I had the same problem with MFGPT Timers and alix (BIOS v0.99). I found that > > if you use a different interrupt than the default 7 for MFGPT (just append > > mfgpt_irq=8 to the kernel commandline), the timer seems to work. > > Indeed. > Strange, it works at least with mfgpt_irq=8 (rtc) and mfgpt_irq=5 (audio): That is very unfortunate. We must continue to investigate. > [ 21.805129] geode-mfgpt: IRQ MSR=0:0 > [ 21.816129] geode-mfgpt: NMI MSR=0:0 > [ 21.827116] geode-mfgpt: Unrestricted sources=0 > [ 21.840979] geode-mfgpt: Registered timer 0 > [ 21.853806] mfgpt-timer: registering the MFGT timer as a clock event. > [ 21.873576] geode: 8 MFGPT timers available. > [ 21.887962] PCI: PCI BIOS revision 2.10 entry at 0xfcd03, last bus=0 > > I noted that "rtc" disappeared, do I have any drawback of this? > I assume that the mfgpt-timer cannot be shared? No. We figured that was the best way to go. I don't know if there are any technical reasons why it can't be shared, other then latency problems. But I would still prefer to figure out why 7 doesn't work - because there is nothing in the hardware or kernel code that should prevent that. Arnd - if you don't mind doing a little bit more debug work. You've already given us the MSRs for 0x51400020 - 0x51400023. Can you now give us 0x51400024-0x51400027, as well as 5140004E? Our current working theory is that IRQ7 (traditionally used by the LPT port) is still conflicting somewhere. Jordan -- Jordan Crouse Systems Software Development Engineer Advanced Micro Devices, Inc. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/