BSP Layers and Reference Images for Yocto Project Software
Introduction
You should read our page for the BSP Layers and Reference Images for the Yocto Project on the main Toradex website before reading this article.
Linux, developed as an open source operating system for IBM computers, was ported to Arm in the early days. Today, Linux holds a significant market share in the embedded world, mainly on Arm devices. The advantages over proprietary embedded operating systems include no royalties or licensing fees, a stable kernel, a vast number of tested drivers, a support base that is not restricted to the employees of a single software company, and the ability to modify and redistribute the source code.
Toradex provides embedded Linux BSPs (Board Support Packages) and reference images for all our current computer on modules. Those BSPs are provided by an in-house development team working side-by-side with the hardware team. This enables us to provide a high-quality Linux port. When it comes to solving issues, the customer can rest assured that they will not be the play ball between different hardware and software providers.
The Yocto Project and OpenEmbedded
Toradex provides and supports Embedded Linux BSPs based on the Yocto Project/OpenEmbedded. We maintain our production-quality OpenEmbedded BSPs and reference distribution layers, meant as a great starting point for our customers. Learn more about the relationship between Toradex and the Yocto Project/OpenEmbedded:
Embedded Linux Offerings
Toradex provides three options for embedded Linux development. Our main website presents the offerings, and our developer website has pages used as entry point for related technical articles:
- Torizon OS / Overview on the Torizon website
- Torizon OS Reference Images for Yocto Project / Overview on the main website
- Toradex BSP Layers and Reference Images for Yocto Project / Overview on the main website
While Torizon OS (both the ready-to-use and the Reference Images versions) and the BSP Reference Images are built on top of the BSP layers, they have fundamental differences. Learn more about them in our Embedded Linux page on the main Toradex website.
This page focuses on the Toradex BSP Layers and Reference Images for Yocto Project. For Torizon, please refer to the Torizon software page.
Releases
Toradex defines a release cycle for the BSP Layers, Reference Images for Yocto Project and Torizon OS.
- Nightly
- Monthly
- Quarterly
- LTS (every 12 months)
Which Release Cycle Should I Use?
To learn more about them and which one you should choose, read our support strategy:
Active Releases
The currently active releases are:
- 6: Release currently under development. Aligned with Yocto Project Kirkstone LTS release. Use of Mainline Kernel v6.0 for most supported modules. Learn more on the Release Notes.
- 5: Latest LTS release. Aligned with the Yocto Project Dunfell LTS release. Learn more on our blog Toradex aligns embedded Linux releases with Yocto Project Long Term Support.
- 3: LTS release for SoMs based on the NXP i.MX 6/6ULL/7 SoCs. Learn more on our blog The motivation behind Toradex Embedded Linux BSP 3.x.
- 2.8: LTS release. It is the last supported software release for Apalis T30 and Colibri VF50, VF61, T20 and T30.
Release Notes
The BSP Layers And Reference Images for Yocto Project Release Notes contains a list of new features and bug-fixes that are planed, and also known issues and limitations.
BSP Layers and Reference Images for Yocto Project
Toradex provides BSP Layers and Reference Images for Yocto Project.
They are:
- A fast and reliable starting point for you to create your own distribution.
- Production-grade quality.
They are not:
- Ready to be used in a production environment without further customization.
Toradex provides binary images of the Reference Images for Yocto Project for your convenience and ease-of-use during your first steps with Toradex hardware. Nevertheless, if you want something that is ready to be used in production, learn more about the differences between the Reference Images for Yocto Project and Torizon and consider starting with Torizon.
Distributions
Toradex provides several distribution policy files based on the Poky one. We provide distro variants for different kernel configurations, summarized in the table below. Even though all distributions set the policy for the graphics stack, for example Weston/Wayland + XWayland, not all images include the graphics libraries: for instance, the Reference Minimal Image is a console-only image.
If you want to know exactly what is defined for each distro, follow the links as they point to the relevant configuration files.
| Distro | kernel base | kernel config |
|---|---|---|
| tdx-xwayland | Downstream kernel from SoC vendor (NXP) | Default (without the PREEMPT_RT patch) |
| tdx-xwayland-rt | Downstream kernel from SoC vendor (NXP) | Fully preemptive (real-time Linux PREEMPT_RT patch) |
| tdx-xwayland-upstream | Mainline kernel | Default (without the PREEMPT_RT patch) |
| tdx-xwayland-upstream-rt | Mainline kernel | Fully preemptive (real-time Linux PREEMPT_RT patch) |
Images
Toradex provides two reference image variants built on top of the distribution variants. Below we list the image variants and their description and some remarkable features. If you want to know exactly all the features, follow the links as they point to the relevant Yocto recipes.
| Image | Description |
|---|---|
| Torizon OS Reference Minimal Image torizon-minimal (Torizon OS BSP) | Torizon OS reference minimal image without a container engine: - Network Manager: NetworkManager - Init system: systemd - OTA Framework: OSTree & Uptane - All other Torizon OS features Refer to Torizon OS Reference Minimal Image Technical Overview and Build Torizon OS from Source With Yocto Project/OpenEmbedded |
| Reference Minimal Image tdx-reference-minimal-image | Minimal image without graphical interface that just boots - Network manager: connman - Init system: systemd - Base command-line packages packagegroup-base-tdx-cli included in packagegroup-tdx-cli.bb |
| Reference Multimedia Image tdx-reference-multimedia-image | Image for BSP verification with Qt and multimedia features - All that is included in the Reference Minimal Image - Graphics stack: Weston / Wayland + XWayland - Graphical User Interface framework: Qt - Camera and Video framework: V4L2 and Gstreamer - All command-line packages included in packagegroup-tdx-cli.bb - All graphical packages included in packagegroup-tdx-graphical.bb - All Qt5 packages included in packagegroup-tdx-qt5.bb |
Source Code
The Linux kernel and U-Boot bootloader source code as well as the Toradex OpenEmbedded layers can be cloned from our GIT server. Sources of our current Linux images are available at git.toradex.com:
- Linux kernel: https://git.toradex.com/cgit/linux-toradex.git/
- U-Boot: https://git.toradex.com/cgit/u-boot-toradex.git/
- OpenEmbedded repo manifest: repo toradex-manifest
Check out the versions of U-Boot, kernel and Yocto/OpenEmbedded in our Embedded Linux Release Matrix.
Artifacts
Artifacts are binaries resulting from Yocto builds, such as pre-built images.
SDKs
We don't maintain or provide SDKs for the reference images. You must build your own Linux SDKs using OpenEmbedded.
Image Binaries
The pre-built binary images are provided by Toradex for your convenience and ease-of-use during your first steps with Toradex hardware.
Choose a Binary
Before installing an image, you must make some choices:
- Choose a release cycle and a release version
- Select a distro and image
- Have at hand the name and version of your Computer on Module
This article goes on about all of those parameters. If you are still in doubt, we suggest that you browse through it again. If you still have questions, we are happy to help through our support channels.
Online Versus Offline Installation
The Toradex Easy Installer allows you to install all of our pre-built images directly from the internet into the Computer on Module internal flash memory. You don't need to download them for offline installation using an SD Card or USB stick, unless you have strong reason to do so, for instance, if your company network blocks our Toradex Easy Installer online feed.
Download Links for Offline Installation
You don't need to download an image, except on special occasions. Read the previous section Online Versus Offline Installation to learn more.
Download pre-built images from the Reference Images for Yocto Project Software Downloads.
Flashing
First, check under which category you fall:
- If your module has come straight from factory and you have never installed anything in it, it will have the Toradex Easy Installer pre-installed. You just need to power it on.
- Otherwise, you must load the Toradex Easy Installer on your module's RAM memory.
Use the Toradex Easy Installer to flash the image into the Computer on Module.
Customization
You will need to customize our Reference Images for Yocto Project. We provide documentation on reproducing our pre-built images with Yocto, and how to build the U-Boot and Linux kernel directly from the source code.
Recreate and Customize BSP with the Yocto Project/OpenEmbedded
For further information on how to recreate and customize our BSPs refer to the article Build a Reference Image with Yocto Project.
Build U-Boot and Linux Kernel
For further information about what Linux kernel and U-Boot branch are valid for which module hardware refers to the Build U-Boot and Linux Kernel from Source Code article.
Toradex Linux Features
Please refer to the BSP Layers and Reference Images Documentation for a full list of resources on how to use the Toradex Linux features.