From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jesse Barnes Date: Thu, 16 Dec 2004 17:42:20 +0000 Subject: Re: [PATCH] add legacy I/O port & memory APIs to /proc/bus/pci Message-Id: <200412160942.20678.jbarnes@engr.sgi.com> List-Id: References: <200412160850.20223.jbarnes@engr.sgi.com> <200412161037.55293.bjorn.helgaas@hp.com> In-Reply-To: <200412161037.55293.bjorn.helgaas@hp.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-pci@atrey.karlin.mff.cuni.cz Cc: Bjorn Helgaas , linux-ia64@vger.kernel.org, linux-kernel@vger.kernel.org, willy@debian.org On Thursday, December 16, 2004 9:37 am, Bjorn Helgaas wrote: > On Thursday 16 December 2004 9:50 am, Jesse Barnes wrote: > > This patch documents the /proc/bus/pci interface and adds some optional > > architecture specific APIs for accessing legacy I/O port and memory > > space. This is necessary on platforms where legacy I/O port space doesn't > > 'soft fail' like it does on PCs, and is useful for systems that can route > > legacy space to different PCI busses. > > But we didn't resolve anything with respect to multiple PCI domains, > did we? As far as I can see, /proc/bus/pci currently doesn't support > multiple domains at all. I don't like the idea of adding new stuff > that we already know is insufficient for machines in the very near > future. True, it's just extending an existing interface, but it > seems like if we're going to the trouble of changing X, we might as > well address multiple domains at the same time. The problem with adding domain support is that it'll break existing users, unless it's added on the side somehow. One thought I had was to document that /proc/bus/pci/ contains only busses from domain 0. Machines with more than 1 domain could create /proc/bus/pci/domain/DDDD directories with busses in the DDDD domain underneath. That wouldn't break existing applications, and would let you get at domains other than 0 if you needed to. Jesse