Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965649AbXAZNFJ (ORCPT ); Fri, 26 Jan 2007 08:05:09 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S965650AbXAZNFJ (ORCPT ); Fri, 26 Jan 2007 08:05:09 -0500 Received: from moutng.kundenserver.de ([212.227.126.171]:57650 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965649AbXAZNFH convert rfc822-to-8bit (ORCPT ); Fri, 26 Jan 2007 08:05:07 -0500 Date: Fri, 26 Jan 2007 13:54:43 +0100 To: "Xavier Bestel" Subject: Re: Bugfixes: PCI devices get assigned redundant IRQs From: "Andreas Block" Cc: linux-kernel@vger.kernel.org Content-Type: text/plain; charset=US-ASCII; format=flowed delsp=yes MIME-Version: 1.0 References: <1169809255.10952.178.camel@frg-rhel40-em64t-03> Content-Transfer-Encoding: 7BIT Message-ID: In-Reply-To: <1169809255.10952.178.camel@frg-rhel40-em64t-03> User-Agent: Opera Mail/9.10 (Win32) X-Provags-ID: kundenserver.de abuse@kundenserver.de login:7ee1d245d6d47e4a96dce2c88f0dd45f X-Provags-ID2: V01U2FsdGVkX1+tg+Uv1Zu/UWJVZc2fGvTqImWVoLnBIGIWQ89GNeUJB3Xp6+ch9J982VtmqKG28G7jF93NNCEeRuPe0X+D5PMab8vWjMbPfdTcY6KqrmVm1w== Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1849 Lines: 51 On Fri, 26 Jan 2007 12:00:55 +0100, Xavier Bestel wrote: > On Fri, 2007-01-26 at 11:50 +0100, Andreas Block wrote: > >> u8 pin, slot; >> - int irq; >> + int irq = 0; > > Aren't there platforms for which irq = 0 is a valid irq ? As far as I understand the PCI spec, the answer to your question seems to be: no (or I'm missing something). Don't get me wrong. I'm not talking about system IRQs, but about the value of the Interrupt Pin Register in PCI configuration space. The PCI Local Bus Specification in Revision 3.0 from 3rd February 2004 says on page 223 about the content of Interrupt Pin register: Value 0x00: _No_ interrupt Values 0x01 to 0x04: Interrupt lines A to D And values 5 to 0xFF are reserved. So I'd say, the "correction" of greater values than four to a value of one seems discussable, too. Because it will break any future changes of the PCI spec. Andreas -- ------------------------------------------------------------------------- _/_/_/_/ Andreas Block _/_/_/_/ Dipl.-Ing. _/_/_/_/ andreas.block@esd-electronics.com _/_/_/ _/_/_/_/_/_/_/ esd electronic system design gmbh _/ _/ _/ _/ Vahrenwalder Str. 207 _/ _/ _/_/_/ _/ _/ D-30165 Hannover _/ _/ _/ _/ Phone: +49-511-37298-0 _/_/_/_/_/_/_/ _/_/_/ Fax: +49-511-37298-68 http://www.esd-electronics.com ------------------------------------------------------------------------- - 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/