Got the first part of the packing phase in place.

Generate kernel.S rather than have it as a manually maintained file.

loader/SConscript

@@ -0,0 +1,77 @@
+# -*- mode: python; coding: utf-8; -*-
+
+#  Codezero -- a microkernel for embedded systems.
+#
+#  Copyright © 2009  B Labs Ltd
+#
+#  This program is free software: you can redistribute it and/or modify it under the terms of the GNU
+#  General Public License as published by the Free Software Foundation, either version 3 of the License, or
+#  (at your option) any later version.
+#
+#  This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even
+#  the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
+#  License for more details.
+#
+#  You should have received a copy of the GNU General Public License along with this program.  If not, see
+#  <http://www.gnu.org/licenses/>.
+#
+#  Author: Russel Winder
+
+import os.path
+import subprocess
+
+Import('environment', 'images')
+
+def ksymToLds(target, source, env):
+    symbols = ['break_virtual']
+    with open(target[0].path, 'w') as asmFile:
+        asmFile.write('''
+/*
+ * %s autogenerated from %s
+ *
+ * This file is included by the loader sources so that any
+ * kernel symbol address can be known in advance and stopped
+ * at by debuggers before virtual memory is enabled.
+ */
+''' % (target[0].name, source[0].name))
+        for symbol in symbols:
+            process = subprocess.Popen('arm-none-eabi-objdump -d ' + source[0].path + ' | grep "<' + symbol + '>"', shell=True, stdout=subprocess.PIPE)
+            assert process.wait() == 0
+            address, name = process.stdout.read().split()
+            assert '<' + symbol + '>:' == name
+            asmFile.write( '''
+.section .text
+.align 4
+.global %s;
+.type	%s, function;
+.equ	%s, %s
+''' % (symbol, symbol, symbol, (hex(int(address, 16) - 0xf0000000))))
+
+def createKernelSFile(target, source, env):
+    with open(target[0].path, 'w') as asmFile:
+        asmFile.write('''
+/* This file defines kernel symbols extracted from the kernel image in their physical address */
+.include "start.axf.S"
+
+.section .kernel
+
+.incbin "%s"
+
+''' % (source[0].path))
+        for image in source[1:]:
+            asmFile.write('''
+.align 4
+.section .%s
+.incbin "%s"
+''' % (os.path.splitext(image.name)[0], image.path))
+
+startAxfS = Command('start.axf.S', images[0], ksymToLds)
+
+kernelS = Command('kernel.S', images + [startAxfS], createKernelSFile)
+
+objects = environment.Object(Glob('*.c') + [kernelS])
+Depends(objects, environment['configFiles'])
+Depends(objects, images)
+program = environment.Program('final', objects)
+
+Return('program')