Debos recipe for Raspberry Pi 4B

This repository contains a debos recipe for the Raspberry Pi 4 Model B.

How to build

Follow these instructions to build the image.

First build

In order to save build time, the base-pack.yaml recipe is prebuilt and stored in a compressed archive. By default, the standard build is configured to extract and use build results from this archive. This is controlled using the variable unpack.

You also might want to overrid the firmware-version variable, since it's likely that a new firmware was released since the last time this repository was updated.

To build the image the first time, using the recipe base-pack.yaml instead of the prebuilt archive, and to fetch the latest firmware version, run the following command:

FIRMWARE_VERSION=$(curl -s https://api.github.com/repos/raspberrypi/firmware/tags | grep name | head -n 1 | cut -d '"' -f 4)
debos -m 8192MB -b kvm -t unpack:false -t firmware_version:$FIRMWARE_VERSION debian-rpi4.yaml

This will also store the results from the recipe base-pack.yaml and replace any previously generated archive. If the base-pack.yaml recipe has been changed, you also want build the image using this command.

Normal build

If you already have generated the base-pack archive and the base-pack.yaml recipe hasn't been changed, you can build the image using:

debos -m 8192MB -b kvm debian-rpi4.yaml

Test with Qemu

The following instructions show, how to test the image in a Qemu environment.

Prerequisite

The instruction are valid for a recent Debian system (it was tested on Bullseye).

A series of package is required to be installed, using the following command:

sudo apt install libguestfs-tools qemu-system-arm qemu-utils

Instructions

To test the image in a Qemu environment, it is recommended to use the following bash script image_run:

#!/bin/bash
# Find boot artifacts
for basename in "vmlinuz" "initrd.img"; do
    if [ -f "$basename" ]; then continue; fi
    fpath=$(virt-ls -a "$1" /boot | grep -E "^$basename-[[:digit:]]" | sort -r | head -n 1)
    echo "Found $fpath!"
    virt-copy-out -a $1 "/boot/$fpath" .
    mv $fpath $basename
done
# Launch Qemu
qemu-system-aarch64 \
    -m 2048 \
    -cpu cortex-a57 \
    -smp 2 \
    -M virt \
    -kernel vmlinuz \
    -initrd initrd.img \
    -append 'root=/dev/vda2' \
    -drive if=none,file=$1,format=qcow2,id=hd \
    -device virtio-blk-pci,drive=hd \
    -device virtio-net-pci,netdev=net0 \
    -netdev user,id=net0,hostfwd=tcp::2222-:22 \
    -nographic

Make the script executable (chmod +x image_run) and use it with the following command

./image_run debian-rpi4.qcow2

You can terminate the Qemu environment by pressing Ctrl + a followed by x.

Please refer to this website for more background information.

Deploy to Raspberry Pi

First, the image needs to be flashed to sd-card.

Flash to sd-card

By default, the recipe outputs a compressed image along with a *.bmap file. Using the command bmaptool the image can be flashed efficiently to an sd-card. This command is provided by the package bmap-tools, which is installed using

sudo apt install bmap-tools 

Finally, the image can be flashed to the sd-card, using the following command:

sudo bmaptool copy debian-rpi4.img.gz <device>

where <device> is to be replaced with the device path the represents the sd-card (e.g. /dev/sdc). This can be identified using the command ls -l /dev/disks/by-id.

Insert the sd-card into the Raspberry Pi after it has been flashed successfully.

Serial Console

The image is configured to allow a serial console connection. This is useful to interact with the Raspberry Pi in headless mode. It is recommended to use a 3.3V FTDI cable for this. With this cable, connect Black to pin 6 (Ground), Yellow to pin 8 (GPIO 14 TXD) and Orange to pin 10 (GPIO 15 RXD) on the 40-Pin GPIO Header as indicated in the Raspberry Pi Documentation. After the FTDI cable has been plugged into the host computer, start the serial console e.g. using screen with:

screen /dev/serial/by-id/<id> 115200

where <id> is to replaced with the correct id of the FTDI cable, which can be identified using the command ls -l /dev/serial/by-id. Note that you can detach from the screen session by pressing Ctrl+a followed by d.

Finally, connect the Raspberry Pi's power source and enjoy!

Notice

This debos recipe is based on the rpi64 recipe of debos-recipes. It contains a modified, updated recipe file and adopts some of the overlays and scripts from the original.

License

To remain inline with the original recipe on which this recipe is based, the same Apache style license applies to this recipe. See the LICENSE file for more details.