Porting.md

To add a new board to the Heads build hopefully you only need to modify the coreboot configuration and add a top-level image configuration.

• Copy one of the existing image configurations, such as config/x230-qubes.config to your new image, config/newarch-qubes.config, and edit the file to change BOARD=x230 to BOARD=newarch.

• Either copy one of the existing config files, such as the config/coreboot-x230.config to config/coreboot-newarch.conf, or use your existing coreboot .config file in its place. You'll want to be sure that it is using a Linux payload named ./bzImage and a Linux initrd named ./initrd.cpio.xz. No command line options are necessary.

• If you want to use menuconfig to reconfigure the coreboot file, it is a little tricky since we have an external config file. From the top level of the Heads directory you can run:

make \
	-C build/coreboot-4.5 \
	DOTCONFIG=../../config/coreboot-newarch.config \
	menuconfig

• The same logic would apply with the linux config file.

make \
        -C build/linux-4.14.62 \
        KCONFIG_CONFIG=../../config/linux-newarch.config \
        menuconfig

• Run make CONFIG=config/newarch-qubes.config to setup the coreboot tree, using the new coreboot config file. This will create the output directory build/coreboot-4.5/newarch/, and after a while, you should have newarch.rom in the top level directory.

• If things don't work, please open an issue on https://github.com/osresearch/heads/issues