From owner-freebsd-hackers Thu Aug 2 11:57:24 2001 Delivered-To: freebsd-hackers@freebsd.org Received: from po3.wam.umd.edu (po3.wam.umd.edu [128.8.10.165]) by hub.freebsd.org (Postfix) with ESMTP id 4AA3A37B403; Thu, 2 Aug 2001 11:57:17 -0700 (PDT) (envelope-from culverk@wam.umd.edu) Received: from rac2.wam.umd.edu (IDENT:root@rac2.wam.umd.edu [128.8.10.142]) by po3.wam.umd.edu (8.9.3/8.9.3) with ESMTP id OAA17413; Thu, 2 Aug 2001 14:57:13 -0400 (EDT) Received: from rac2.wam.umd.edu (IDENT:sendmail@localhost [127.0.0.1]) by rac2.wam.umd.edu (8.9.3/8.9.3) with SMTP id OAA01385; Thu, 2 Aug 2001 14:55:28 -0400 (EDT) Received: from localhost (culverk@localhost) by rac2.wam.umd.edu (8.9.3/8.9.3) with ESMTP id OAA01381; Thu, 2 Aug 2001 14:55:28 -0400 (EDT) X-Authentication-Warning: rac2.wam.umd.edu: culverk owned process doing -bs Date: Thu, 2 Aug 2001 14:55:28 -0400 (EDT) From: Kenneth Wayne Culver To: Julian Elischer Cc: John Baldwin , freebsd-hackers@FreeBSD.org, craig , Terry Lambert , Rik van Riel Subject: Re: How to visit physical memory above 4G? In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG > No > The space is linear in physical space and if you have PCI/64 > capable devices they can access it all too. > > (In fact 64 bit addresses have been supported even in 32 bit wide PCI > since day 1). OK, then what was that whole paging thing everyone was talking about, I thought that was partially done in hardware on the chipset of the motherboard... or was that completely in the operating system? Ken > > On Thu, 2 Aug 2001, Kenneth Wayne Culver wrote: > > > BUT, don't the motherboards also have to support this? And isn't it only > > supported through some wierd segmentation thing? > > > > KEn > > > > On Thu, 2 Aug 2001, John Baldwin wrote: > > > > > > > > On 02-Aug-01 Kenneth Wayne Culver wrote: > > > > Also, the PIII CAN'T natively support more than 4GB of ram. If a > > > > particular PIII motherboard supports this, then it's using some kind of > > > > wierd chipset that allows this to happen. 4GB is the limit with a 32 bit > > > > chip I believe; and the PIII is a 32-bit chip. > > > > > > > > Ken > > > > > > Go look at some Intel docs. P6 chips since the Pentium Pro (yes, before > > > Pentium II) have supported PAE which allows for a 36-bit physical address. > > > > > > -- > > > > > > John Baldwin -- http://www.FreeBSD.org/~jhb/ > > > PGP Key: http://www.baldwin.cx/~john/pgpkey.asc > > > "Power Users Use the Power to Serve!" - http://www.FreeBSD.org/ > > > > > > > > > To Unsubscribe: send mail to majordomo@FreeBSD.org > > with "unsubscribe freebsd-hackers" in the body of the message > > > > To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message