Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030213AbWIESuY (ORCPT ); Tue, 5 Sep 2006 14:50:24 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030214AbWIESuY (ORCPT ); Tue, 5 Sep 2006 14:50:24 -0400 Received: from e35.co.us.ibm.com ([32.97.110.153]:28906 "EHLO e35.co.us.ibm.com") by vger.kernel.org with ESMTP id S1030213AbWIESuW (ORCPT ); Tue, 5 Sep 2006 14:50:22 -0400 Date: Tue, 5 Sep 2006 13:50:20 -0500 To: Benjamin Herrenschmidt Cc: "Zhang, Yanmin" , linuxppc-dev@ozlabs.org, linux-pci maillist , Yanmin Zhang , LKML , Rajesh Shah Subject: Re: pci error recovery procedure Message-ID: <20060905185020.GD7139@austin.ibm.com> References: <1157008212.20092.36.camel@ymzhang-perf.sh.intel.com> <20060831175001.GE8704@austin.ibm.com> <1157081629.20092.167.camel@ymzhang-perf.sh.intel.com> <20060901212548.GS8704@austin.ibm.com> <1157348850.20092.304.camel@ymzhang-perf.sh.intel.com> <1157360592.22705.46.camel@localhost.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1157360592.22705.46.camel@localhost.localdomain> User-Agent: Mutt/1.5.11 From: linas@austin.ibm.com (Linas Vepstas) Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1507 Lines: 35 On Mon, Sep 04, 2006 at 07:03:12PM +1000, Benjamin Herrenschmidt wrote: > > > As you know, all functions of a device share the same bus number and 5 bit dev number. > > They just have different 3 bit function number. We could deduce if functions are in the same > > device (slot). > > Until you have a P2P bridge ... And this is not theoretical: for example, the matrox graphics cards: 0000:c8:01.0 PCI bridge: Hint Corp HB6 Universal PCI-PCI bridge (non-transparent mode) (rev 13) 0000:c9:00.0 VGA compatible controller: Matrox Graphics, Inc. MGA G400 AGP (rev 85) Now, I could have sworn there was another device behind this bridge, some serial or joystick controller or something, although this particular card doesn't seem to have it. ------ It's not clear to me what hardware may show up in the future. For example, someone may build a 32x PCI-E card that will act as a bridge to a drawer with half-a-dozen ordinary PCI-X slots in it. This is perhaps a bit hypothetical, but changing the API will make it harder to implement eror recovery for such a system. FWIW, there is at least one pSeries system in the lab which has several hundred PCI slots attached to it, although I've never done testing on it. Hmm. Maybe its time I did ... --linas - 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/