Creating an ARM64 boot image for a Raspberry Pi 4B in a Docker container from a either a Ubuntu Bionic or Ubuntu Eoan (current/dev) RPI3 boot image

(Initially adapted from project at https://github.com/tsaarni/docker-deb-builder )

Overview

This creates a docker container to build an Ubuntu Eoan 19.10 or Ubuntu Bionic 18.04 server image for a Raspberry Pi 4B using a Ubuntu Disco 19.04 build container. This is has been run successfully (self-hosting?) with docker on a RPI 4B with 4Gb of ram to generate both kernels and images. This setup will compile a current RPI kernel, current RPI userland, get current RPI firmware, and copy them all to the ubuntu image.

Current capatiblity options on the 4Gb RPI4:

Boot Option	How to Enable	Maximum Accessible RAM
u-boot at /boot/firmware/kernel8.img	sudo cp /boot/firmware/uboot.bin /boot/firmware/kernel8.img ; sudo reboot	4 Gb (Default)
uncompressed linux kernel at /boot/firmware/kernel8.img	sudo cp /boot/firmware/kernel8.img.nouboot /boot/firmware/kernel8.img ; sudo reboot	4Gb

Default is booting with u-boot just like a normal ubuntu image.

Note that the u-boot in the ubuntu package u-boot-rpi doesn't yet support the RPI. The u-boot here has been compiled from @agherzan's WIP u-boot fork here.

Note that this container runs in PRIVILEGED MODE.

Feel free to offer suggestions on how to make this setup safer without making the build an order of magnitude slower. :/

To build an Ubuntu Eoan Raspberry Pi 4B image run following commands:

1. Make sure you have a recent install of Docker. (There is no Docker Host OS version requirement.) Tested using Docker running on Ubuntu Eoan & macos Mojave, but this should also work fine in Ubuntu Disco and maybe also Ubuntu Bionic.

Installation instructions for Ubuntu: https://docs.docker.com/install/linux/docker-ce/ubuntu/

1.5. Some have reported that qemu-user-static needs to be installed on your HOST system before this setup works:

sudo apt install qemu-user-static -y

(Note that this is installed in the container, and I don't know why this helps... but FYI.)

2. Clone Build build environment

Clone the docker-rpi4-imagebuilder (the repository you are reading now):

git clone https://github.com/satmandu/docker-rpi4-imagebuilder
cd docker-rpi4-imagebuilder

3. Build package from inside source directory

git pull ; time ./build-image

A first build takes about 30 min on my Skylake build machine. A second build takes about 10 min due to the use of ccache if I have xz compression disabled and just use lz4 for image compression, or 25 min if I use both.

xz compression be toggled by adding XZ=1 at the command line like this: git pull ; XZ=1 time ./build-image

Just building the kernel debs (and not the image) and putting them into the output folder can be toggled by adding JUSTDEBS=1 at the command line like this: git pull ; JUSTDEBS=1 time ./build-image

After a successful build you will find the eoan-preinstalled-server-arm64+raspi4.img___kernel___timestamp.lz4 file in your specified output directory (defaults to output ). (Failure will lead to a build_fail.log in that folder.)

Currently the images are under 700Mb compressed with xz, or about 1.3Gb compressed with lz4. The xz images are about 50 Mb larger than the base ubuntu images.

4. Installing image to sd card

Use the instructions here: https://ubuntu.com/download/iot/installation-media

Example:

lz4cat ~/Downloads/eoan-preinstalled-server-arm64+raspi4.img.lz4 | sudo dd of=< drive address > bs=32M

or

xzcat ~/Downloads/eoan-preinstalled-server-arm64+raspi4.img.xz | sudo dd of=< drive address > bs=32M

Note that you want to replace instances of "xzcat" with "lzcat" since this setup uses the much faster lz4 to compress the images created in the docker container.

1st Login

The default login for this image is unchanged from the ubuntu server default image: ubuntu/ubuntu. Note also that the RPI4 SHOULD Be connected to ethernet for first login, as the ubuntu startup cloud sequence wants a connection. After the network starts, you should be able to ssh to the IP of the RPI with username ubuntu, where you will be prompted to change the password. As the ubuntu cloud setup is not disabled, you have to wait about five minutes for login to be available.

Do setup the Time Zone using sudo dpkg-reconfigure tzdata when you first login. You can use connmanctl to configure the wireless network.

Note that running this repeatedly will create much container cruft.

Consider running docker container prune on your docker machine to reclaim unused space.

Credit to:

https://jamesachambers.com/raspberry-pi-ubuntu-server-18-04-2-installation-guide/

https://blog.cloudkernels.net/posts/rpi4-64bit-image/

https://andrei.gherzan.ro/linux/raspbian-rpi-64/ https://andrei.gherzan.ro/linux/raspbian-rpi4-64/

https://github.com/sakaki-/bcm2711-kernel-bis