Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758756AbYF1BJk (ORCPT ); Fri, 27 Jun 2008 21:09:40 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753474AbYF1BJb (ORCPT ); Fri, 27 Jun 2008 21:09:31 -0400 Received: from rtsoft3.corbina.net ([85.21.88.6]:8804 "EHLO buildserver.ru.mvista.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1753368AbYF1BJa (ORCPT ); Fri, 27 Jun 2008 21:09:30 -0400 Date: Sat, 28 Jun 2008 05:09:28 +0400 From: Anton Vorontsov To: Ingo Molnar Cc: linux-ide@vger.kernel.org, Bartlomiej Zolnierkiewicz , Alan Cox , Sergei Shtylyov , linux-kernel@vger.kernel.org, Thomas Gleixner , Steven Rostedt , Daniel Walker Subject: Re: [PATCH v2 -rt] ide: workaround buggy hardware issues with preemptable hardirqs Message-ID: <20080628010928.GA4248@polina.dev.rtsoft.ru> Reply-To: avorontsov@ru.mvista.com References: <20080623234037.GA6793@polina.dev.rtsoft.ru> <20080623235141.GB17297@elte.hu> <20080624000016.GA12547@polina.dev.rtsoft.ru> <20080625123431.GA25452@polina.dev.rtsoft.ru> <20080628005436.GA1956@polina.dev.rtsoft.ru> MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Disposition: inline In-Reply-To: <20080628005436.GA1956@polina.dev.rtsoft.ru> User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2014 Lines: 51 On Sat, Jun 28, 2008 at 04:54:36AM +0400, Anton Vorontsov wrote: > IDE interrupt handler relies on the fact that, if necessary, hardirqs > will re-trigger on ISR exit. The assumption is valid for level sensitive > interrupts. > > But some hardware (namely ULi M5228 in the ULi M1575 "Super South Brige") > behaves in a strange way: it asserts interrupts as edge sensitive. And > because preemptable IRQ handler disables PIC's interrupt, PIC will likely > miss it. > > This patch fixes following issue: > > ALI15X3: IDE controller (0x10b9:0x5229 rev 0xc8) at PCI slot 0001:03:1f.0 > ALI15X3: 100% native mode on irq 18 > ide0: BM-DMA at 0x1120-0x1127, BIOS settings: hda:PIO, hdb:PIO > ide1: BM-DMA at 0x1128-0x112f, BIOS settings: hdc:PIO, hdd:PIO > hda: Optiarc DVD RW AD-7190A, ATAPI CD/DVD-ROM drive > hda: UDMA/66 mode selected > ide0 at 0x1100-0x1107,0x110a on irq 18 > ide-cd: cmd 0x5a timed out > hda: lost interrupt > hda: ATAPI 12X DVD-ROM DVD-R-RAM CD-R/RW drive, 2048kB Cache > Uniform CD-ROM driver Revision: 3.20 > ide-cd: cmd 0x3 timed out > hda: lost interrupt > ide-cd: cmd 0x3 timed out > hda: lost interrupt > ... > > It would be great to re-configure the ULi bridge or ULi IDE controller > to behave sanely, but no one knows how or if this is possible at all > (no available specifications). Btw, thanks to Jeff Garzik for mentioning this link: http://gkernel.sourceforge.net/specs/ Though, from a brief glance there is nothing much useful for this ULi chip. The only thing I gathered is that IDE controller does not provide any means of configuring its IRQs behaviour, so it is indeed ULi's bridge problems. It doesn't change anything, just another data point... -- Anton Vorontsov email: cbouatmailru@gmail.com irc://irc.freenode.net/bd2 -- 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/