From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756901AbYAVUxw (ORCPT ); Tue, 22 Jan 2008 15:53:52 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753112AbYAVUxm (ORCPT ); Tue, 22 Jan 2008 15:53:42 -0500 Received: from slowhand.arndnet.de ([88.198.19.76]:42252 "EHLO mail.unitix.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753026AbYAVUxl (ORCPT ); Tue, 22 Jan 2008 15:53:41 -0500 Message-ID: <47965806.6080903@i4.informatik.rwth-aachen.de> Date: Tue, 22 Jan 2008 21:54:30 +0100 From: Arnd Hannemann User-Agent: Thunderbird 2.0.0.6 (X11/20071022) MIME-Version: 1.0 To: Jordan Crouse CC: Lars Heete , Andres Salomon , Linux Kernel Mailing List Subject: Re: 2.6.24-rc8 hangs at mfgpt-timer 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> <20080122192757.GC5241@cosmic.amd.com> In-Reply-To: <20080122192757.GC5241@cosmic.amd.com> Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, Jordan Crouse schrieb: >> Indeed. >> Strange, it works at least with mfgpt_irq=8 (rtc) and mfgpt_irq=5 (audio): > > I have most excellent news. I was able to get tinyBIOS booting on my > development platform. I looked at the problem with the debugger and > I think I might have found something. It looks like the interrupt is > firing immediately before the clock is enabled. In the handler, we > were returning immediately if the clock wasn't enabled (and not clearing > the event), so we were caught in a classic interrupt storm. > > The attached patch rearranges the code so that the handler is installed > before we setup the interrupt (so we have somebody to listen to the > immediate interrupt), and it makes sure that we clear the event in the IRQ > handler regardless of the state of the timer tick. This patch indeed solves the problem. The board boots fine. Great work! 0: 48 XT-PIC-XT timer 2: 0 XT-PIC-XT cascade 4: 493 XT-PIC-XT serial 7: 25875 XT-PIC-XT mfgpt-timer 8: 3 XT-PIC-XT rtc 10: 56963 XT-PIC-XT eth0 15: 1 XT-PIC-XT ehci_hcd:usb1, ohci_hcd:usb2 NMI: 0 Non-maskable interrupts TRM: 0 Thermal event interrupts SPU: 0 Spurious interrupts ERR: 0 > > I'm not 100% sure why this happens on IRQ7 but not on 5 or 8, but it might > have something to do with the interrupts already being enabled on the other > vectors. Anyway, please try this test patch and let me know what happens. Congratulations for this long but successful remote debugging ;-) Greetings, Arnd