#!/bin/sh

#
# Copyright (c) 2021 Martin Decky
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
#
# - Redistributions of source code must retain the above copyright
#   notice, this list of conditions and the following disclaimer.
# - Redistributions in binary form must reproduce the above copyright
#   notice, this list of conditions and the following disclaimer in the
#   documentation and/or other materials provided with the distribution.
# - The name of the author may not be used to endorse or promote products
#   derived from this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
# OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
# IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
# NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
# THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#

# This script allows to deploy HelenOS conveniently to the HiKey 960 board
# using the fastboot protocol. The fastboot mechanism is provided as a part
# of the default UEFI firmware on HiKey 960.
#
# The implementation of the fastboot mechanism on HiKey 960 has several
# quirks and this script tries to accommodate for them:
#
# * The boot image must be compressed by GZip. Uncompressed boot images are
#   rejected.
#
# * The compressed boot image must end with a device tree blob (even if
#   the device tree is not actually processed). A missing device tree blob
#   crashes the fastboot mechanism.
#
# * A RAM disk must be included in the final fastboot image. A missing RAM
#   disk crashes the fastboot mechanism. We use a fake blob for that purpose.

check_error() {
	if [ "$1" -ne "0" ] ; then
		echo
		echo "Error: $2"

		exit 1
	fi
}

SCRIPT_DIR="$(readlink -f $(dirname "$0"))"

if [ "$#" -lt "1" ] ; then
	echo "Usage: $0 <image.boot>"
	exit 2
fi

IMAGE="$1"
IMAGE_GZ="${IMAGE}.gz"
IMAGE_GZ_DTB="${IMAGE_GZ}+dtb"
IMAGE_FASTBOOT="${IMAGE}.fastboot"

if [ ! -f "${IMAGE}" ] ; then
	echo "Error: ${IMAGE} is not a file"
	exit 3
fi

# Compress the image
gzip -c "${IMAGE}" > "${IMAGE_GZ}"
check_error $? "Compressing ${IMAGE}"

# Append the DTB
cat "${IMAGE_GZ}" "${SCRIPT_DIR}/hi3660-hikey960.dtb" > "${IMAGE_GZ_DTB}"
check_error $? "Appending DTB to ${IMAGE_GZ}"

# Create the fastboot image with a fake "RAM disk"
"${SCRIPT_DIR}/mkfastboot" --kernel ${IMAGE_GZ_DTB} --ramdisk "${SCRIPT_DIR}/hikey960.rd" --base 0x0 --tags-addr 0x07a00000 --kernel_offset 0x00080000 --ramdisk_offset 0x07c00000 --output "${IMAGE_FASTBOOT}"
check_error $? "Converting ${IMAGE_GZ_DTB} to a fastboot image"

# Deploy the fastboot image on a HiKey 960 board connected to the host machine
fastboot boot "${IMAGE_FASTBOOT}"
check_error $? "Deploying ${IMAGE_FASTBOOT}"