Building a Linux Image with Yocto

Our Linux software stack is based on the Yocto project.

In order to build it, we use kas, which fetches and builds bitbake based project. If you already know about Yocto, you don’t have to use kas. Our layer, meta-scobc, can be used as a regular yocto layer.

Setup the Build Environment

The meta-xilinx-tool layer depends on some packages that are not available in Ubuntu 24.04.

To install them, you need to add Ubuntu 22.04 (Jammy) repositories to your system.

$ sudo tee /etc/apt/sources.list.d/jammy.list << 'EOF'
deb http://archive.ubuntu.com/ubuntu jammy main universe
deb http://archive.ubuntu.com/ubuntu jammy-updates main universe
deb http://security.ubuntu.com/ubuntu jammy-security main universe
EOF
$ sudo tee /etc/apt/preferences.d/jammy-pin << 'EOF'
Package: *
Pin: release a=jammy
Pin-Priority: -1

Package: libncurses5 libtinfo5
Pin: release a=jammy
Pin-Priority: 990
EOF

Then, install the required packages.

$ sudo apt update
$ sudo apt install binutils chrpath cpio diffstat file g++ gawk gcc \
                   git git-lfs libncurses5 libtinfo5 lz4 make python3 \
                   rpcsvc-proto zstd

Next, install uv, which is a tool to manage Python virtual environments.

$ curl -LsSf https://astral.sh/uv/install.sh | sh

Clone the Repository

$ git clone https://github.com/spacecubics/meta-scobc
$ cd meta-scobc

meta-scobc uses Git Large File Storage (Git LFS). Make sure you install it.

Install and Enable the Required Python Packages

$ uv sync
$ source .venv/bin/activate

Build the Minimal Image

With kas, it’s easier than bitbake to build the whole system. Just let it do the work with the following command.

From meta-scobc version scobc-v1-v0.3.0, SDT(System Device Tree)-based builds are the default.

For Space Grade

$ kas build kas/scobc-v1.yml

build/tmp/deploy/images/versal-scobc-v1-ve2302i-sdt-full/ will contain the generated image files.

$ ls -1F build/tmp/deploy/images/versal-scobc-v1-ve2302i-sdt-full/*.wic
build/tmp/deploy/images/versal-scobc-v1-ve2302i-sdt-full/sc-image-minimal-versal-scobc-v1-ve2302i-sdt-full-yyyyMMddHHmmss.wic
build/tmp/deploy/images/versal-scobc-v1-ve2302i-sdt-full/sc-image-minimal-versal-scobc-v1-ve2302i-sdt-full.wic@

sc-image-minimal-versal-scobc-v1-ve2302i-sdt-full.wic is a symlink to the latest build.

For Developer Grade

$ kas build kas/scobc-v1-devgrade.yml

build/tmp/deploy/images/versal-scobc-v1-ve2302e-sdt-full/ will contain the generated image files.

$ ls -1F build/tmp/deploy/images/versal-scobc-v1-ve2302e-sdt-full/*.wic
build/tmp/deploy/images/versal-scobc-v1-ve2302e-sdt-full/sc-image-minimal-versal-scobc-v1-ve2302e-sdt-full-yyyyMMddHHmmss.wic
build/tmp/deploy/images/versal-scobc-v1-ve2302e-sdt-full/sc-image-minimal-versal-scobc-v1-ve2302e-sdt-full.wic@

sc-image-minimal-versal-scobc-v1-ve2302e-sdt-full.wic is a symlink to the latest build.