DTB updater for https://github.com/Debian/raspi3-image-spec/issues/37

update_DT_RPi3.sh

#!/bin/bash

# DTB UPDATER 0.2 for Raspberry Pi 3 (aarch64)
# Copyright (C) 2018 Lorenzo Ancora
# DTB UPDATER 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.
# DTB UPDATER 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 <https://www.gnu.org/licenses/>.

#
# EXAMPLE: update_DT_RPi3.sh "https://gist.github.com/chschlue/e0e02ecb1c455a7c8db3a53f9b408d6b/raw/16ec1953f34534a941bb90b2f6f42f30888157fc/bcm2710-rpi-3-b.dtb" "bcm2710-rpi-3-b.dtb"
# RETURN CODES: 0 (SUCCESS), 1 (FAILURE), 2 (FAILURE)
#

DTBURL=$1                    # Full URL of the DTB file.
DTBDST="/boot/firmware/"     # Firmware directory of the Raspberry Pi 3.
DTBFIL=$2                    # Destination filename under DTBDST.
CKNAME="sha256.txt"          # File which contains the OUTPUT of "sha256sum --tag <DTBFILE>", placed in the execution directory of this script.

function exitFailure () {
        echo "FAILURE: $1."
        if [ $2 -eq 1 ]; then
                echo "WARNING: your Wi-Fi interfaces may not be recognized."
                echo "WARNING: make sure that the latest" $DTBFIL "is in" $DTBDST "before rebooting."
        fi
        exit $2
}

if [ ! -f $DTBDST$DTBFIL ]; then
        echo "Installing DTB file for Raspberry Pi 3 from" $DTBURL "..."
        wget --quiet --timeout=7 --random-wait --tries=3 --retry-connrefused $DTBURL --output-document=$DTBDST$DTBFIL
        if [ -f $DTBDST$DTBFIL ]; then
                echo "DTB STATUS: UPDATED."
        else exitFailure "DOWNLOAD FAILED" 1
        fi
        cp $CKNAME $DTBDST$CKNAME
        pushd "$DTBDST" > /dev/null
        sha256sum --status --strict --check $CKNAME
        ckRes=$?
        popd > /dev/null
        if [ $ckRes -eq 0 ]; then
                echo "DTB INTEGRITY: CONFIRMED."
                rm -f $DTBDST$CKNAME
        else exitFailure "NEW DTB FILE IS CORRUPTED" 1
        fi
        exit 0 # SUCCESS
else exitFailure "DTB ALREADY INSTALLED (PLEASE BACKUP AND DELETE $DTBFIL FROM $DTBDST)" 2
fi

### EXAMPLE OUTPUT: ###
# Installing DTB file for Raspberry Pi 3 from https://gist.github.com/chschlue/e0e02ecb1c455a7c8db3a53f9b408d6b/raw/16ec1953f34534a941bb90b2f6f42f30888157fc/bcm2710-rpi-3-b.dtb ...
# DTB STATUS: UPDATED.
# DTB INTEGRITY: CONFIRMED.
###       EOF       ###