extlinux_warning() { echo "==> WARNING: U-Boot uses Extlinux support to boot up. For setting it up, edit /boot/extlinux/extlinux.conf" } flash_uboot() { echo "A new U-Boot version needs to be flashed onto /dev/mmcblk0." echo "Do you want to do this now? [y|N]" read -r shouldwe if [[ $shouldwe =~ ^([yY][eE][sS]|[yY])$ ]]; then dd if=/boot/u-boot.imx of=/dev/mmcblk0 bs=512 seek=2 sync else echo "You can do this later by running:" echo "# dd if=/boot/u-boot.imx of=/dev/mmcblk0 bs=512 seek=2" fi extlinux_warning } ## arg 1: the new package version post_install() { flash_uboot } ## arg 1: the new package version ## arg 2: the old package version post_upgrade() { flash_uboot }