Add conversion script to convert 2GB boards to 32bit.

TEST=Launch incremental buildbots for these overlays and confirm they
     are converted to 32bit successfully.

Change-Id: I5ba9294d8b00204110c304a48c0c5f3c0cae9751
Reviewed-by: Mike Frysinger <>
Reviewed-by: Sonny Rao <>
Tested-by: David James <>
Reviewed-by: Brian Harring <>
diff --git a/chroot_version_hooks.d/32_64bit_convert_2gb_boards b/chroot_version_hooks.d/32_64bit_convert_2gb_boards
new file mode 100644
index 0000000..506231d
--- /dev/null
+++ b/chroot_version_hooks.d/32_64bit_convert_2gb_boards
@@ -0,0 +1,20 @@
+# Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+# This is meant to happen immediately after we update these boards
+# from 64bit to 32bit.  It moves the existing build root out of the
+# way and re-creates the build root.  The user must remove the copy
+# of the old build root manually if it is not needed.
+for board in x86-mario x86-alex x86-zgb x86-alex_he x86-zgb_he kiev; do
+  build="/build/${board}"
+  if [[ -d ${build} ]] ; then
+    info "Moving 64bit ${board} to ${board}.64bit"
+    info "If you don't need it, please run "
+    info "sudo rm -rf ${build}.64bit"
+    sudo mv ${build}{,.64bit}
+    info "Running setup_board --board=${board}"
+    ~/trunk/src/scripts/setup_board --board=${board} --skip_chroot_upgrade
+  fi