What's new since dunfell?
The new releases are based on the official yocto kirkstone release ( Yocto Project Version 4.0 ). This step brings a lot of updated package versions but should not introduce any real 'breaking' changes. When coming from rocko, the changes introduced with Yocto dunfell still apply, please see below.
Kernel version
For imx8mm (Tanaro) and imx8mp (Trizeps8plus) based systems the kernel version changed from 5.10 to 5.15, based on the nxp kernel tree.
Manual
A manual is now available as confluence page, see Manual.
Sourcecode / Board support package
The source code can be found in the public git repositories at git.seco.com/seco-ne.
The manifests README can be used as entrypoint to build images from scratch: README.
Release cycle
Releases are created mostly every four weeks and build for all platforms. We do not necessarily test all these combinations.
The release artifacts and documentation can be found at the Download page.
The related source code is found at: git.seco.com/seco-ne/yocto
What's new since rocko?
The SECO Northern Europe releases, formerly known as Garz & Fricke, have some breaking changes, that have been introduced with the switch of the yocto base version from 'rocko' ( Yocto Project Version 2.4 ) to the newer yocto base version 'dunfell' ( Yocto Project Version 3.1 ).
Some of the are directly related to the yocto upgrade, but few are design decisions that are only relevant for G&F Yocto distribution. Most of these decisions follow the base idea to develop closer to the 'mainline' source tree which allows faster upgrade cycles of the yocto version as well as integrated components.
Autojobs
The 'autojobs' feature has not been ported to the new version of the distribution. As it was possible to execute any binary from an external source it is considered as a major security issue and will not be available in this way anymore.
Init system
The init system changed from System V to systemd. This means that all scripts in /etc/init.d are gone and replaced by systemd units. Systemd uses so-called unit-files to configure services to start and stop. The tool systemctl is the main userspace tool to control these if needed.
With systemd comes journald as main system log. These logs are accessed using the tool journalctl.
See Understanding-and-using-systemd for further information.
Kernel version
The kernel version for the i.MX6 platforms changed from 4.1.15 to 5.10 kernel based on the mainline tree.
As common for open source projects, there are different kernel derivates available. The main tree is the so called 'mainline' kernel, hosted at kernel.org with Linus Torvalds as maintainer. This kernel is normally the base for all distribution kernels, where less or more patches are added.
For embedded/arm platforms it is common, that the platform vendor creates a kernel variant containing specific drivers and platform code. The support is then (sometimes) adopted and integrated into the mainline kernel tree over time.
For i.MX6 platform the support in the mainline kernel tree is good enough that we decided to use it as base for this platforms.
For i.MX8 variant the support in the mainline tree is still under construction. The kernel for these platforms is still based on the nxp kernel tree.
Manual
The monolithic manual was removed from the release artifacts and will be replaced by a wiki based version, which is not yet available online.
QT Version
The dunfell version comes with Qt 5.15, which will be the last Qt 5 version. Later Qt versions are based on Qt 6.
Release cycle
With the new distribution's base version, we also switched to a new release cycle. Releases are created mostly every four weeks and build for all platforms. We do not necessarily test all these combinations.
The release artifacts and documentation can be found at the Download page.
The related source code is found at: git.seco.com/seco-ne/yocto
Shared Config
The shared config system based on xml files has been the main 'per device'-configuration and provisioning system on G&F systems since years. It has always been Garz & Fricke only and had drawbacks on some corner cases.
With the new dunfell release the system is still present, but changes the scope from shared-Configuration (using the same configuration instantly on all installed OSes) to initial-Configuration: Most settings are applied to standard linux config files during OS installation from the installed xml files. This allows less changes to installed standard software (more mainline) and less access to the xml files during boot (faster startup).
The relevant change to the user is, that changing the configuration on the fly with sconfig only changes the xml file, but not the active system configuration. Further steps are needed to apply it to the image as well.
We recommend to use standard linux tools for common configuration things, like nmcli to change the network configuration.
Sourcecode / Board support package
We removed the static source tarball from the release artifacts, which have been needed to build images from the scratch with rocko and previous releases.
The source code for this yocto distribution is currently hosted on git.seco.com/seco-ne/yocto from where it can be directly checked out to create a source tree locally.
Window manager
The window manger in the previous yocto releases has been the X11 system. This has been exchanged with Wayland and uses Weston as compositor.
Wayland uses a different protocol to display applications, so a recompilation of existing applications is needed.
There is an X on Wayland project, to continue running native X11 applications, which we don't have tested yet.