From owner-cvs-all@FreeBSD.ORG Mon May 24 07:09:00 2004 Return-Path: Delivered-To: cvs-all@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 9A62D16A4CE; Mon, 24 May 2004 07:09:00 -0700 (PDT) Received: from mail-gw1.york.ac.uk (mail-gw1.york.ac.uk [144.32.128.246]) by mx1.FreeBSD.org (Postfix) with ESMTP id C2B5A43D2F; Mon, 24 May 2004 07:08:59 -0700 (PDT) (envelope-from gavin.atkinson@ury.york.ac.uk) Received: from buffy.york.ac.uk (buffy.york.ac.uk [144.32.226.160]) by mail-gw1.york.ac.uk (8.12.10/8.12.10) with ESMTP id i4OE8B9A001320; Mon, 24 May 2004 15:08:12 +0100 (BST) Received: from buffy.york.ac.uk (localhost.york.ac.uk [127.0.0.1]) by buffy.york.ac.uk (8.12.11/8.12.11) with ESMTP id i4O9WkQ8007170; Mon, 24 May 2004 10:32:46 +0100 (BST) (envelope-from gavin.atkinson@ury.york.ac.uk) Received: (from ga9@localhost) by buffy.york.ac.uk (8.12.11/8.12.11/Submit) id i4O9WiRr007169; Mon, 24 May 2004 10:32:44 +0100 (BST) (envelope-from gavin.atkinson@ury.york.ac.uk) X-Authentication-Warning: buffy.york.ac.uk: ga9 set sender to gavin.atkinson@ury.york.ac.uk using -f From: Gavin Atkinson To: "M. Warner Losh" In-Reply-To: <20040523.215736.44518029.imp@bsdimp.com> References: <20040522103658.P58631@root.org> <20040523204728.U66525@root.org> <20040523.215736.44518029.imp@bsdimp.com> Content-Type: text/plain Content-Transfer-Encoding: 7bit Message-Id: <1085391163.6814.6.camel@buffy.york.ac.uk> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.6 Date: Mon, 24 May 2004 10:32:44 +0100 X-York-MailScanner: Found to be clean cc: cvs-src@freebsd.org cc: src-committers@freebsd.org cc: scottl@freebsd.org cc: cvs-all@freebsd.org cc: nate@root.org Subject: Re: cvs commit: src/sys/dev/pci pci.c X-BeenThere: cvs-all@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: CVS commit messages for the entire tree List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 24 May 2004 14:09:00 -0000 On Mon, 2004-05-24 at 04:57, M. Warner Losh wrote: > In message: <20040523204728.U66525@root.org> > Nate Lawson writes: > : On Sat, 22 May 2004, M. Warner Losh wrote: > : > Well, we're talking exclusively about the vendor, device, subvendor, > : > subdevice, class, subclass and progif fields, which are obstensively > : > read-only. However, the pci standards are self-contradictory. The > : > main 2.2 one says they are read-only (without defining what that means > : > that I could find), yet the pciide spec says that progif had writable > : > bits... > : > : I think the progif is the only one of that list that you need to restore, > : as per your reading of the specs. Since the others are identifiers, they > : probably don't need to be restored. > > Things are vague enough in the spec that this is totally > unsatisfying. We're just guessing based on hunches, which I really > don't like, which is why I saved/restored everything. Could we perhaps read them on restore and only write to them if necessary? That way we reduce the possibility of tickling bugs in the silicon by writing to read-only registers for chips that don't actually need it? Gavin