From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Fri, 30 Sep 2005 14:49:24 +0100 (BST) Received: from extgw-uk.mips.com ([62.254.210.129]:63763 "EHLO bacchus.net.dhis.org") by ftp.linux-mips.org with ESMTP id S3465576AbVI3NtI (ORCPT ); Fri, 30 Sep 2005 14:49:08 +0100 Received: from dea.linux-mips.net (localhost.localdomain [127.0.0.1]) by bacchus.net.dhis.org (8.13.4/8.13.1) with ESMTP id j8UDn0Fk008867; Fri, 30 Sep 2005 14:49:00 +0100 Received: (from ralf@localhost) by dea.linux-mips.net (8.13.4/8.13.4/Submit) id j8UDn0hV008866; Fri, 30 Sep 2005 14:49:00 +0100 Date: Fri, 30 Sep 2005 14:49:00 +0100 From: Ralf Baechle To: Franck Cc: linux-mips@linux-mips.org Subject: Re: DISCONTIGMEM suuport on 32 bits MIPS Message-ID: <20050930134900.GB3083@linux-mips.org> References: <20050926122114.GC3175@linux-mips.org> <20050929235025.GC3983@linux-mips.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.4.2.1i 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: 9098 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: ralf@linux-mips.org Precedence: bulk X-list: linux-mips On Fri, Sep 30, 2005 at 02:40:31PM +0200, Franck wrote: > > > > IP27 currently the only system that absolutely needs discontiguous > > > > memory in order to work at all. A few other systems could make use of > > > > discontiguous memory to reduce the waste of memory - the family of > > > > Broadcom SB1 based systems comes to mind. > > > > > > Isn't discontiguous memory common for embedded system as well ? I > > > thought so...Anyways can we make discontiguous memory thing move into > > > generic MIPS code so every future needs for that will profit ? I > > > looked at other arch, and they seem to implement it that way (in > > > arch/xxx/mm/discontig.c). > > > > Yes, that would be a good thing. There are several platforms that could > > make good use of discontiguous memory support such as Broadcom's Sibyte > > SoCs with their insanely large hole in the memory map but also others. > > > > Ok I'll try to do that soon (maybe in 1 or 2 weeks). I looked at the > ARM's code and I should be able to do the same on MIPS. Should I keep > IP27 data structure and code although ARM's ones seem to be easier to > understand ? The IP27 code is a little obscure which partly is explained by it's age; it's been the first NUMA system to be supported in Linux. After a quick look the ARM code seems a little to simple to deal with such a system, so I suggest you take a look at arch/ia64/mm/discontig.c instead. Ralf