From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Wed, 07 Mar 2007 13:23:23 +0000 (GMT) Received: from elvis.franken.de ([193.175.24.41]:22214 "EHLO elvis.franken.de") by ftp.linux-mips.org with ESMTP id S20021589AbXCGNXV (ORCPT ); Wed, 7 Mar 2007 13:23:21 +0000 Received: from uucp (helo=solo.franken.de) by elvis.franken.de with local-bsmtp (Exim 3.36 #1) id 1HOw3u-0007wL-00; Wed, 07 Mar 2007 14:20:10 +0100 Received: by solo.franken.de (Postfix, from userid 1000) id 04481C2349; Wed, 7 Mar 2007 14:18:42 +0100 (CET) Date: Wed, 7 Mar 2007 14:18:42 +0100 To: Franck Bui-Huu Cc: mbizon@freebox.fr, linux-mips Subject: Re: [PATCH 0/2] FLATMEM: allow memory to start at pfn != 0 [take #2] Message-ID: <20070307131842.GA9361@alpha.franken.de> References: <116841864595-git-send-email-fbuihuu@gmail.com> <1172879147.964.65.camel@sakura.staff.proxad.net> <1173112433.7093.36.camel@sakura.staff.proxad.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.9i From: tsbogend@alpha.franken.de (Thomas Bogendoerfer) Return-Path: X-Envelope-To: <"|/home/ecartis/ecartis -s linux-mips"> (uid 0) X-Orcpt: rfc822;linux-mips@linux-mips.org Original-Recipient: rfc822;linux-mips@linux-mips.org X-archive-position: 14384 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: tsbogend@alpha.franken.de Precedence: bulk X-list: linux-mips On Tue, Mar 06, 2007 at 10:39:59PM +0100, Franck Bui-Huu wrote: > I think you missed PAGE_OFFSET meaning... > > PAGE_OFFSET is the start of the kernel virtual address space and > before this patchset pa(PAGE_OFFSET) was always 0. > > In your case, you said: > > PAGE_OFFSET = 0x80000000 > PHYS_OFFSET = 0x10000000 > > this means that the first kernel virtual address is 0x80000000 and the > corresponding physical address is 0x10000000. If you load your kernel > at 0x9000xxxx, it will be loaded in physical memory located at > 0x2000xxxx which is obviously not what you want. which sound like a very bogus setup for at leat 32bit MIPS. The mapping virtual 0x80000000 to physical 0x00000000 is a CPU thing and can't be changed. Thomas. -- Crap can work. Given enough thrust pigs will fly, but it's not necessary a good idea. [ RFC1925, 2.3 ]