From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Sun, 4 Nov 2001 21:11:09 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Sun, 4 Nov 2001 21:10:59 -0500 Received: from neon-gw-l3.transmeta.com ([63.209.4.196]:13837 "EHLO neon-gw.transmeta.com") by vger.kernel.org with ESMTP id ; Sun, 4 Nov 2001 21:10:45 -0500 To: linux-kernel@vger.kernel.org From: "H. Peter Anvin" Subject: Re: The PCI ID Repository Date: 4 Nov 2001 18:10:22 -0800 Organization: Transmeta Corporation, Santa Clara CA Message-ID: <9s4see$egc$1@cesium.transmeta.com> In-Reply-To: <20011104170202.A3370@ucw.cz> <200111050044.fA50i8o182130@saturn.cs.uml.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT Disclaimer: Not speaking for Transmeta in any way, shape, or form. Copyright: Copyright 2001 H. Peter Anvin - All Rights Reserved Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Followup to: <200111050044.fA50i8o182130@saturn.cs.uml.edu> By author: "Albert D. Cahalan" In newsgroup: linux.dev.kernel > > Tundra provides an example: Universe, Universe II, Universe IIB > > These chips are the same device in some sense; they are all > PCI-to-VME bridges. (damn popular too) The programming interface > is incompatible, so they get different revisions. Tundra isn't > alone in interpreting the PCI spec this way. > Another interpretation, which seems pretty common (we use this one at Transmeta, for example) is to treat the version ID as the "minor revision" (indicating an upward compatible change) and the device ID as the "major revision" (change this to indicate an incompatible change in the programming interface.) Unfortunately PCI doesn't have the very nice "compatible with" list that ISAPnP has -- that, and the "human readable string" were very useful features of the ISAPnP spec. -hpa -- at work, in private! "Unix gives you enough rope to shoot yourself in the foot." http://www.zytor.com/~hpa/puzzle.txt