AMD openSIL & Coreboot Pull Requests For Phoenix AM5 Support

Last week the 3mdeb firmware consulting firm released the first open-source firmware for a modern AMD Ryzen AM5 platform with their work to port AMD openSIL and Coreboot in their downstream Dasharo flavor to an MSI desktop ATX motherboard. Now that it's working out well, 3mdeb is working to upstream their AM5 platform support and Phoenix SoC support into upstream AMD openSIL as well as Coreboot.

3mdeb firmware engineer Michał Żygowski today opened an AMD openSIL pull request in working to upstream the necessary changes for AM5 support and the Phoenix Ryzen 8000 series processors.

THe pull request brings some fixes that were needed in conjunction with their Coreboot bring-up, updates for handling Phoenix desktop CPUs, MMIO handling updates, support for the Promontory21 IP block for chipset initialization, missing SMU / USB / GFX initialization, and other missing elements compared to the current Phoenix proof-of-concept code within AMD openSIL.

Żygowski remarked in the pull request:

"With these changes, I was able to bring up an AM5 Phoenix platform with an AMD B850 chipset and boot Ubuntu 26.04 and Windows 11 using coreboot."

Also today there were pull requests for upstreaming the Coreboot changes. This includes various AMD Phoenix changes for Coreboot, Promontory21 handling, and other changes for AM5 processors. It also includes an initial tree for the MSI PRO B850-P WIFI motherboard that 3mdeb has been focusing their work on with this port.

Nice seeing them get their openSIL and Coreboot changes out for review to upstream these additions. Those wanting to consume it in a nice easy-to-use experience will want to check out 3mdeb's Dasharo firmware release for the MSI PRO B850-P WIFI. I'll have up my tests with that board soon.