Coreboot 4.22 Released: Initial AMD OpenSIL Code Added, 17 New Motherboards

A new release of Coreboot is available today as the increasingly popular open-source system firmware solution that's used by Chromebooks, increasing hyperscaler / data center industry interest due to increased code transparency and security, System76 laptops, and more. Coreboot 4.22 is the new release and brings initial AMD OpenSIL code integration, 17 new motherboard ports, and more. Coreboot 4.22 will be succeeded next year by Coreboot 24.02.

Before getting to the Coreboot 4.22 features, this is the last Coreboot 4.xx. Beginning next February with the next planned release, the version scheme will change. Like many other software projects, Coreboot is switching to a YEAR.MONTH date based versioning approach. Coreboot 24.02 as such will be the next version coming out in February.

As for the feature changes to find with Coreboot 4.22, highlights include, x86 support for .data sections for pre-memory stages, support for the CBFS cache for pre-memory stages and ramstage, support for running Microsoft Windows on more Coreboot-based Chromebooks, and ACPI table generation for ARM64. Coreboot also now sets the vBIOS checksum when filling the VFCT table as the AMD Windows driver checks the checksum of the vBIOS data. Without this, the AMD Radeon Windows graphics driver fails to load.

Also significant with Coreboot 4.22 is adding the initial AMD openSIL implementation has made it into Coreboot but still in its very early stages. Coreboot is carrying a mirror of the reference AMD openSIL code and in the future may contain extra additions. For now like with upstream AMD openSIL this is only working on one AMD EPYC Genoa reference board.

AMD OpenSIL will eventually replace AGESA in a few years time and be supported across the entire AMD CPU product portfolio for client, embedded, and servers. The AMD OpenSIL code has been open-source for a few months and continues to be under active development with hopes of being production ready in 2026.

Coreboot 4.22 also has initial AMD EPYC 9004 "Genoa" SoC support along with the Onyx reference board. There are 17 new motherboards supported by Coreboot 4.22:

- AMD Onyx
- Google: Anraggar
- Google: Brox
- Google: Chinchou
- Google: Ciri
- Google: Deku
- Google: Deku4ES
- Google: Dexi
- Google: Dochi
- Google: Nokris
- Google: Quandiso
- Google: Rex4ES EC ISH
- Intel: Meteorlake-P RVP with Chrome EC for non-Prod Silicon
- Purism Librem 11
- Purism Librem L1UM v2
- Siemens FA EHL
- Supermicro X11SSW-F

More details on Coreboot 4.22 (downloaded as Coreboot 4.22.01 due to a brown paper bag issue) can be found via the Coreboot blog.

Somewhat related is our friends at the 3mdeb consulting firm having another Dasharo vPub event next week on 7 December at 5PM UTC. This is a virtual event for talking open-source firmware (Coreboot / Dasharo) on motherboards while enjoying beverages.