Presented by

  • Jeremy Kerr

    Jeremy Kerr

    Jeremy Kerr is a Linux and open source systems developer, working on the kernel, drivers, firmware and related plumbing, plus a little hardware development too. Jeremy is the technical lead of Code Construct, a small consultancy developing in the open source and embedded-systems area. Previously, he has worked for IBM's Linux technology center on their POWER server platforms, and Canonical's hardware enablement team. Jeremy's first contribution to the Linux kernel was accepted on the 23rd of Feburary, 2004. His second was a fix, for that same piece of code, on the 24th of February, 2004.


In late 2022, we developed a LibreBMC platform - an entirely open source Baseboard Management Controller (BMC). Everything — including the hardware design, CPU implementation, system-on-chip peripherals, FPGA gateware, and Linux-based firmware — is available under an open source license to verify and/or reimplement. We used this platform to boot and manage an IBM POWER9 AC922 ("witherspoon") server. The AC922 is the compute component of the Summit and Sierra supercomputers, the two fastest worldwide until mid-2020. While booting the AC922 was our near-term goal, this work demonstrates the possibility and potential of a fully-open sideband management stack for server applications - an area under increasing scrutiny for platform verifiability, security and trust. The LibreBMC platform itself is a great example of an application of a software-defined system implementation: we use the Microwatt POWER ISA softcore, plus a few other peripheral blocks - also open source, of course. Running on a standard FPGA device, we can boot a vanilla Linux system, which forms the base of our OpenBMC port to manage the AC922 server. This presentation covers the adventures we had in bringing-up the LibreBMC platform, from intricate hardware reworks to the changes needed in the platform control systems, in order to boot the AC922 server. We'll show where the platform worked well, as well as challenges in our implementation. Of course, there's plenty of future possibilities for the LibreBMC platform, which we'll present with some introductory material should you want to participate. The work was a collaboration between the OpenPOWER Foundation, IBM and Code Construct. YouTube: LA Archive: