ROSE Build Configuration

Sets up a workspace for building the ROSE reference distribution using the OpenEmbedded build system.

License

These scripts and configuration files are distributed unter the MIT License.

Building an Image

The following steps show, how a ROSE image can be built for the Raspberry Pi 4.

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Dependencies

For information on system reququirements and packages to be installed, please refer to the Yocto Project documentation.

The following packages are needed in addition:

python3-venv

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Fetching the source

mkdir rose
cd rose
python3 -m venv .venv
. .venv/bin/activate
pip install west
west init -m https://github.com/rose-project/rose-config
west update

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Build

cd rose
. config/build-env

This sets up the build environment and switches to the build dir. If the build dir does not yet exist, if also initializes build configuration files in build/conf.

To run a build simply call:

bitbake rose-image

After successful built, there should now be an image file tmp-glibc/deploy/images/raspberrypi4/rose-image-raspberrypi4.rootfs.wic.bz2.

NOTE

In case you are running Ubuntu 24 or later, you might see an permission error. As a workaround you can run this command with root rights: "echo 0 > /proc/sys/kernel/apparmor_restrict_unprivileged_userns". For details see: https://lists.yoctoproject.org/g/yocto/topic/workaround_for_uid_map_error/106192359

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Flashing an SD-Card

The image can be copied to an SD-Card e.g. using bzcat:

WARNING: Make sure to use the right block device e.g. with lsblk. You will overwrite data somewhere else on your computer otherwise.

sudo -s
bzcat tmp-glibc/deploy/images/raspberrypi4/rose-image-raspberrypi4.rootfs.wic.bz2 > /dev/sdX
sync
exit

Now plug the SD card to your Raspberry Pi and power it up. If you connect a monitor via HDMI you should get a console where you can run e.g. the kmscube demo application.

Login user is root.

A serial console is available through the Rapsberry Pi IO header.

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Change ROSE Revision

The west tool will manage the revision of the sources to fetch using its manifest file in the subdirectory config. This subderectory contains the rose-config git repository. To change to a different revision of ROSE, you change configuration by fetching a different revision of rose-config and then calling west update again.

Building the SDK

You can build an SDK package that does includes a toolchain, headers and libraries for cross compiling. To build the SDK, first source the environment and then run the Bitbake task populate_sdk:

bitbake -c populate_sdk rose-image

This will generate a self extracting installer script in the build directory, e.g. tmp-glibc/deploy/sdk/oecore-rose-image-x86_64-cortexa72-raspberrypi4-toolchain-0.1.sh

The SDK works independent of Bitbake and can be installed to any location on the system.

./oecore-rose-image-x86_64-cortexa72-raspberrypi4-toolchain-0.1.sh
ROSE SDK installer version 0.1
==============================
Enter target directory for SDK (default: /usr/local/oecore-x86_64): ~/Projects/ROSE/sdk
You are about to install the SDK to "/home/<USER>/Projects/ROSE/sdk". Proceed [Y/n]? Y
Extracting SDK...................................................................................................done
Setting it up...done
SDK has been successfully set up and is ready to be used.
Each time you wish to use the SDK in a new shell session, you need to source the environment setup script e.g.
 $ . /home/<USER>/Projects/ROSE/sdk/environment-setup-cortexa72-oe-linux

After extracting the SDK, an environment script can be sourced to set up the build environment:

. /home/<USER>/Projects/ROSE/sdk/environment-setup-cortexa72-oe-linux
echo $CC
aarch64-oe-linux-gcc -mcpu=cortex-a72+crc -mbranch-protection=standard --sysroot=/home/<USER>/Projects/ROSE/sdk/sysroots/cortexa72-oe-linux