From owner-freebsd-arch Tue Dec 12 23:28:52 2000 From owner-freebsd-arch@FreeBSD.ORG Tue Dec 12 23:28:50 2000 Return-Path: Delivered-To: freebsd-arch@freebsd.org Received: from mass.osd.bsdi.com (adsl-63-202-176-64.dsl.snfc21.pacbell.net [63.202.176.64]) by hub.freebsd.org (Postfix) with ESMTP id 92B2137B400 for ; Tue, 12 Dec 2000 23:28:49 -0800 (PST) Received: from mass.osd.bsdi.com (localhost [127.0.0.1]) by mass.osd.bsdi.com (8.11.1/8.11.1) with ESMTP id eBD7cc307071 for ; Tue, 12 Dec 2000 23:38:38 -0800 (PST) (envelope-from msmith@mass.osd.bsdi.com) Message-Id: <200012130738.eBD7cc307071@mass.osd.bsdi.com> X-Mailer: exmh version 2.1.1 10/15/1999 To: arch@FreeBSD.ORG Subject: Re: Proposed bus address typedef. In-reply-to: Your message of "Tue, 12 Dec 2000 23:24:57 PST." <20001212232457.X16205@fw.wintelcom.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Tue, 12 Dec 2000 23:38:38 -0800 From: Mike Smith Sender: msmith@mass.osd.bsdi.com Sender: owner-freebsd-arch@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > * Mike Smith [001212 23:20] wrote: > > > > I'd like to propose some changes to the way we represent bus addresses, to > > deal with situations where u_long (IMO not a good choice to begin with) > > is too small. > > Sure sounds like a nescessary change. It's only "necessary" really in this one case, although I'd like to step away from "u_long" just because it's so vague. > > Specifically, I'd like to be able to deal with x86 systems in PAE mode, > > where physical addresses are 36 bits in size. > > Er, don't PAE machines use segmentation registers? There's no > 64bit registers are there? There are no 64-bit registers, no. > If that's not true, any chance on it becoming a complile time option > to save cycles on non PAE machines? That would definitely be a worthwhile optimisation, although it would lead to nasty binary compatibility issues between PAE and non-PAE driver modules, for example. -- ... every activity meets with opposition, everyone who acts has his rivals and unfortunately opponents also. But not because people want to be opponents, rather because the tasks and relationships force people to take different points of view. [Dr. Fritz Todt] V I C T O R Y N O T V E N G E A N C E To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message