grub-dumpdevtree

#!/bin/sh
#
# Copyright (C) 2009  Free Software Foundation, Inc.
#
# GRUB 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.
#
# GRUB 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 GRUB.  If not, see <http://www.gnu.org/licenses/>.

if [ "x$1" = "x" ]; then
   echo "Filename required".
fi

ioreg -lw0 -p IODeviceTree -n efi -r -x |grep device-properties | sed 's/.*<//;s/>.*//;' | xxd -r -p > $1