From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from omta01sl.mx.bigpond.com (omta01sl.mx.bigpond.com [144.140.92.153]) by ozlabs.org (Postfix) with ESMTP id F2608DDE31 for ; Wed, 14 Feb 2007 13:38:47 +1100 (EST) Date: Wed, 14 Feb 2007 13:08:46 +1030 From: Alan Modra To: Josh Boyer , linuxppc-dev@ozlabs.org Subject: Re: [PATCH 7/16] Early serial debug support for PPC44x Message-ID: <20070214023846.GC8541@bubble.grove.modra.org> References: <20070213061024.DA1ABDDD0C@ozlabs.org> <1171379087.4003.40.camel@zod.rchland.ibm.com> <20070214001622.GB11491@localhost.localdomain> <20070214010235.GB19430@crusty.rchland.ibm.com> <20070214010044.GG11491@localhost.localdomain> <20070214020012.GB8541@bubble.grove.modra.org> <20070214020251.GI11491@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20070214020251.GI11491@localhost.localdomain> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Wed, Feb 14, 2007 at 01:02:51PM +1100, David Gibson wrote: > On Wed, Feb 14, 2007 at 12:30:12PM +1030, Alan Modra wrote: > > On Wed, Feb 14, 2007 at 12:00:44PM +1100, David Gibson wrote: > > > On Tue, Feb 13, 2007 at 07:02:36PM -0600, Josh Boyer wrote: > > > > On Wed, Feb 14, 2007 at 11:16:22AM +1100, David Gibson wrote: > > > > > I'm using a 64-bit constant there, but for me at least the assembler > > > > > is able to handle manipulating it in constant expressions. > > > > > > > > [jwboyer@zod ~]$ powerpc-440-linux-gnu-as --version > > > > GNU assembler 2.15 > > > > > > > > This is a crosstool built toolchain with binutils 2.15 and gcc 3.4.1. > > > > Which versions are you using? > > > > > > Hmm.. I appear to have binutils-2.17. That could be it. > > > > > > It would be nice to support the older binutils too, but I'm not sure > > > how to get around this without considerable inconvenience. > > > > I would guess that this isn't a matter of how old the assembler is, > > but how the assembler was built. If built on a 32-bit host with no > > 64-bit targets supported, then most internal assembler variables > > are 32-bit and 64-bit constants are not handled very well. > > > > You probably should avoid 64-bit expressions on a 32-bit target. > > Well, yes, but how. No idea, but I haven't even looked at the code in question. I'm just pointing out the toolchain limitation. It sounds like what you've done requires that people build their binutils with --enable-64-bit-bfd or choose support for an extra 64-bit target, eg. --enable-targets=powerpc64-linux > This 32-bit target has 36-bit physical > addresses. All those expressions do is pull the high and low 32-bit > words from literals. -- Alan Modra IBM OzLabs - Linux Technology Centre