From owner-freebsd-arm@FreeBSD.ORG Tue Sep 18 22:40:14 2007 Return-Path: Delivered-To: freebsd-arm@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 12DBA16A420 for ; Tue, 18 Sep 2007 22:40:14 +0000 (UTC) (envelope-from nb@synthcom.com) Received: from synthcom.com (static-71-245-103-2.ptldor.fios.verizon.net [71.245.103.2]) by mx1.freebsd.org (Postfix) with ESMTP id DFC8F13C4B6 for ; Tue, 18 Sep 2007 22:40:13 +0000 (UTC) (envelope-from nb@synthcom.com) Received: from static-71-245-103-2.ptldor.fios.verizon.net (static-71-245-103-2.ptldor.fios.verizon.net [71.245.103.2]) by synthcom.com (8.13.8/8.13.8) with ESMTP id l8IMeDx7052101 for ; Tue, 18 Sep 2007 15:40:13 -0700 (PDT) (envelope-from nb@synthcom.com) Date: Tue, 18 Sep 2007 15:40:13 -0700 (PDT) From: Neil Bradley cc: freebsd-arm@freebsd.org In-Reply-To: <62362.2001:6f8:101e:0:20e:cff:fe6d:6adb.1190154987.squirrel@webmail.alpha-tierchen.de> Message-ID: <20070918153651.G51724@synthcom.com> References: <20070918182508.V24397@fw.reifenberger.com> <46F0064C.3080702@uchicago.edu> <20070918220327.V25238@fw.reifenberger.com> <20070918151418.Y51724@synthcom.com> <62362.2001:6f8:101e:0:20e:cff:fe6d:6adb.1190154987.squirrel@webmail.alpha-tierchen.de> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-3.0 (synthcom.com [71.245.103.2]); Tue, 18 Sep 2007 15:40:13 -0700 (PDT) Subject: Re: 64bit integer problem? X-BeenThere: freebsd-arm@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Porting FreeBSD to the StrongARM Processor List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 18 Sep 2007 22:40:14 -0000 >> ARM Isn't a big endian architecture - it's little endian by default. > According to the ARM reference manual there is no default endianess. It > rather says that it is implementation defined whether the machine supports > little endian or big endian, or even both. All ARM architectures come up out of reset in little endian mode. It takes extra instructions to put it in big endian mode. I would call that a default endianness. ;-) For example, the PowerPC is a big endian architecture, but you can put it in little endian, but its default is still big endian. It's actually a bit worse because you can also (in some ARM architectures) set whether or not the I/O is big or little endian independently, but it still defaults to little endian. None of the ARM architectures I've worked with (XScale, ARM9, ARM7, ARM11) have ever come up by default in big endian. -->Neil ---------------------------------------------------------------------------- C. Neil Bradley - KE7IXP - The one eyed man in the land of the blind is not king. He's a prisoner.