Using Zephyr to Build Smaller Driver Domains for Virtualized Vehicle Systems

In Software-Defined Vehicle (SDV) architectures, virtualization is an important technique for isolating software functions. SoDeV, an SDV platform being developed by Automotive Grade Linux, uses Xen for virtualization. In Xen, a Driver Domain (DomD) owns physical devices and provides para-virtualized interfaces to other domains. Zephyr is a good fit for this role because it combines broad device support with a small footprint, enabling compact and well-isolated driver domains.

In this session, we will present our work on running Zephyr as a Xen driver domain, including current upstream progress. We will explain why smaller Zephyr-based driver domains are attractive, and discuss practical challenges that appear in real systems, such as partitioning hardware cleanly across domains, handling shared resources like clock control, and dealing with the associated challenges on the Xen side. We will also demonstrate Zephyr’s DomD support live—expected to be upstream by the time of the session—on the Renesas/Retronik Sparrow-Hawk V4H Board and Raspberry Pi 5.

Through this demonstration and discussion, attendees will see what is already working today, what benefits this approach can bring, and how the ideas may be applied in their own projects. We also hope to share the remaining open challenges with the community and encourage discussion on how Zephyr-based driver domains can grow into a practical open-source building block for future SDV systems.