From owner-svn-src-user@FreeBSD.ORG  Wed Feb  3 03:26:01 2010
Return-Path: <owner-svn-src-user@FreeBSD.ORG>
Delivered-To: svn-src-user@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 4ED4A1065692;
	Wed,  3 Feb 2010 03:26:01 +0000 (UTC) (envelope-from imp@FreeBSD.org)
Received: from svn.freebsd.org (svn.freebsd.org [IPv6:2001:4f8:fff6::2c])
	by mx1.freebsd.org (Postfix) with ESMTP id 3F1908FC15;
	Wed,  3 Feb 2010 03:26:01 +0000 (UTC)
Received: from svn.freebsd.org (localhost [127.0.0.1])
	by svn.freebsd.org (8.14.3/8.14.3) with ESMTP id o133Q1EE062693;
	Wed, 3 Feb 2010 03:26:01 GMT (envelope-from imp@svn.freebsd.org)
Received: (from imp@localhost)
	by svn.freebsd.org (8.14.3/8.14.3/Submit) id o133Q1bt062691;
	Wed, 3 Feb 2010 03:26:01 GMT (envelope-from imp@svn.freebsd.org)
Message-Id: <201002030326.o133Q1bt062691@svn.freebsd.org>
From: Warner Losh <imp@FreeBSD.org>
Date: Wed, 3 Feb 2010 03:26:01 +0000 (UTC)
To: src-committers@freebsd.org, svn-src-user@freebsd.org
X-SVN-Group: user
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Cc: 
Subject: svn commit: r203413 - user/imp/tbemd
X-BeenThere: svn-src-user@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: "SVN commit messages for the experimental &quot; user&quot;
	src tree" <svn-src-user.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/svn-src-user>,
	<mailto:svn-src-user-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/svn-src-user>
List-Post: <mailto:svn-src-user@freebsd.org>
List-Help: <mailto:svn-src-user-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/svn-src-user>,
	<mailto:svn-src-user-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Wed, 03 Feb 2010 03:26:01 -0000

Author: imp
Date: Wed Feb  3 03:26:00 2010
New Revision: 203413
URL: http://svn.freebsd.org/changeset/base/203413

Log:
  Describe what I'm going to do to kill TARGET_BIG_ENDIAN

Added:
  user/imp/tbemd/README-BRANCH

Added: user/imp/tbemd/README-BRANCH
==============================================================================
--- /dev/null	00:00:00 1970	(empty, because file is newly added)
+++ user/imp/tbemd/README-BRANCH	Wed Feb  3 03:26:00 2010	(r203413)
@@ -0,0 +1,24 @@
+TARGET_BIG_ENDIAN must die
+
+Changes in MACHINE_ARCH:
+
+mips (big endian)	mipseb
+mips (little endian)	mipsel
+arm (little endian)	arm		For historical reasons
+arm (big endian)	armeb
+
+What we call today MACHINE_ARCH is really MACHINE_CPUARCH.  This is
+called MACHINE_CPU on NetBSD, but FreeBSD already uses MACHINE_CPU for
+other purposes.  In general $MACHINE_ARCH -> $MACHINE_CPUARCH in most
+places in the tree.  MACHINE_CPUARCH is defined in bsd.own.mk, since
+it is dependent on the bsd tree, actually.  All the translation from
+MACHINE_ARCH to MACHINE_CPUARCH assumes that all members of that
+family are supported by one set of files on FreeBSD.  So mips files
+have support for both big and little endian.  But MACHINE_ARCH
+determines the default binaries that are generated.
+
+We'll likely need to have a MACHINE_ABI at some point.  Both MIPS and
+ARM have multiple ABIs, and we'll need something to be the default,
+and different CPUs within a family might have different defaults.
+Etc.  Plus there's t he need for multilib.  However, issues like this
+are beyond the scope of this branch.