#!/usr/bin/bash
# set -x
if [[ "$(uname -m)" == arm* || "$(uname -m)" == aarch64 ]]
then
COMMAND="$1"
KERNEL_VERSION="$2"
#BOOT_DIR_ABS="$3"
#KERNEL_IMAGE="$4"
[ -f /etc/u-boot.conf ] && source /etc/u-boot.conf || true
[ -z "$FIRMWAREDT" ] || FirmwareDT=$FIRMWAREDT
if [[ $FirmwareDT == "True" ]]
then
# if we want to use firmware DT we remove symlink to current kernel DT
if [ -h /boot/dtb ]; then
rm -f /boot/dtb
fi
exit 0
fi
# Setup a /boot/dtb -> /boot/dtb-$newest_kernel_version symlink so that
# u-boot can find the correct dtb to load.
#
# If invoked to 'add' a new kernel, find the newest based on `sort`ing
# the kernel versions dtb. If 'remove', then follow basically the same
# procedure but exclude the version currently being removed.
#
# The theory of operation here is that, while newer kernels may add new
# dtb nodes and fields, as upstreaming hw support for some particular
# device progresses, it should never make backward incompatible changes.
# So it should always be safe to use a newer dtb with an older kernel.
list_dtb_versions() {
excluded_version="$1"
for dtbdir in /boot/dtb-*; do
dtbver=${dtbdir#*-}
if [ "$dtbver" != "$excluded_version" ]; then
echo $dtbver
fi
done
}
setup_dtb_link() {
ver=`list_dtb_versions $1 | sort -r --sort=version | head -1`
if [ -h /boot/dtb ]; then
rm -f /boot/dtb
fi
ln -s dtb-$ver /boot/dtb
}
ret=0
case "$COMMAND" in
add)
# If we're adding a kernel we want that version
if [ -h /boot/dtb ]; then
rm -f /boot/dtb
fi
ln -s dtb-$KERNEL_VERSION /boot/dtb
ret=$?
;;
remove)
setup_dtb_link $KERNEL_VERSION
ret=$?
;;
esac
exit $ret
else
# Just exit on non ARM
exit 0
fi
