From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paul Walmsley Subject: Re: [PATCH 2/2] i2c: i2c-omap: Call request_irq with IRQF_DISABLED Date: Thu, 12 Mar 2009 18:04:11 -0600 (MDT) Message-ID: References: <7d7e7dd1a4c64c732a21bdfcf2bd42556be708c3.1236345858.git.Ext-Ari.Kauppi@nokia.com> <20090310005222.GE19758@fluff.org.uk> <1236839178.6478.40.camel@kauppi-desktop> <1236844467.6478.103.camel@kauppi-desktop> <1236857625.6478.163.camel@kauppi-desktop> Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Return-path: Received: from utopia.booyaka.com ([72.9.107.138]:40220 "EHLO utopia.booyaka.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750878AbZCMAEO (ORCPT ); Thu, 12 Mar 2009 20:04:14 -0400 In-Reply-To: <1236857625.6478.163.camel@kauppi-desktop> Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: "Kauppi Ari (EXT-Ixonos/Oulu)" Cc: "linux-omap@vger.kernel.org" (cc's trimmed to drop Ben, i2c list) Hello Ari, On Thu, 12 Mar 2009, Kauppi Ari (EXT-Ixonos/Oulu) wrote: > On Thu, 2009-03-12 at 10:58 +0100, ext Paul Walmsley wrote: > > Thanks for the details. Can you extract the list of spurious IRQ warnings > > that you're getting, and post them? I suspect that, like I2C, many of the > > driver ISRs are not reading back the device interrupt status registers > > after they clear them. > > Sure, > > Here is "grep -hoa 'write for irq.*' *.log | sort | uniq -c" from the > most problematic case (step 2 in above process). It should be noted that > the messages are always in pairs, ie. there are two consecutive messages > in the logs with only microseconds between them. I have divided the > counts reported by uniq -c by two in the list below. > > Boot count: 6628 > 1 write for irq 12 > 1 write for irq 25 > 1 write for irq 33 > 10 write for irq 37 > 29532 write for irq 56 > 12 write for irq 67 > 1 write for irq 71 > 281 write for irq 73 > 114 write for irq 83 > 407 write for irq 86 > > I have also heard that with other use cases irq 17 and 21 should be in > the list, too. The single ones from 12,25,33,71 are probably just > one-offs and should not be taken too seriously, 37/67 are corner cases > but 73/83/86 are definitely valid measurements. Would you be willing to test some patches that might resolve most of these spurious IRQs? They are here: http://www.pwsan.com/omap/spurious-irq-fix.tar.gz They at least boot okay on a 3430SDP, but since I don't have a test case to reproduce the spurious IRQs, I haven't done any further testing. Thanks for your help with this - - Paul