From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dietmar Hahn Subject: Re: [RFC][PATCH]mini-os: big-endian mini-os on ia64 Date: Wed, 28 Feb 2007 10:05:53 +0100 Message-ID: <200702281005.53895.dietmar.hahn@fujitsu-siemens.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: Content-Disposition: inline List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xensource.com Errors-To: xen-devel-bounces@lists.xensource.com To: Keir Fraser Cc: xen-devel@lists.xensource.com, Grzegorz Milos , Xen-ia64-devel List-Id: xen-devel@lists.xenproject.org Am Mittwoch, 28. Februar 2007 09:37 schrieb Keir Fraser: > On 28/2/07 08:25, "Dietmar Hahn" wrote: > >> I don;t think we'd have a problem with incorportaing support for ia64-be > >> if there's a good reason for it (a better reason than "because it's > >> possible"). > > > > I understand this. > > Doing this for an OS that has pre-existing dependencies on being big-endian > (like your BS2000, presumably) I can understand. But I don't see why adding > contrary-endianness support to minios is part of your roadmap when your end > goal is the porting of a completely different OS? If it's part of a > work-scoping exercise then maybe that's understandable, but I don't see why > we'd necessarily take the resulting minios modifications upstream. I did the mini-os port to ia64 as a starting point to get familiar with the internals of xen. The big-endian stuff in mini-os was a "work-scoping exercise" for me, but after getting big-endianess extensions into ia64-xen this was an offer to all developers interested in testing/developing the big-endian feature in xen-ia64. > >> It would be less ugly and I think less prone to missing some open-coded > >> accesses. Open-coding the SWAP()s is pretty grim. > > > > Yes I see this. It's simply more work and more code is touched but from > > the design view it's a lot better. > > If this is OK for you, I will try this and send a new patch as a > > proposal. > > *If* we decide that this is a worthwhile exercise at all for minios, then I > think this has to be the way to go. I understand this. Thanks. Dietmar.