Coreboot on AMD Turin: A Firmware Showdown

Running Coreboot on the Gigabyte MZ33-AR1 motherboard with AMD's newest Turin server processor presented unexpected challenges. AMD's provided firmware blobs proved insufficient to release the CPU from a PSP reset. A workaround involving injecting Coreboot into the vendor firmware and flashing it back was implemented, but this wasn't ideal. The article delves into the AMD PSP firmware structure, including EFS, PSP, and BIOS directories, detailing how comparing vendor and Coreboot firmware differences, specifically fixing SPI speeds, eSPI configuration, and Multi Gen EFS values, led to successful booting. However, using public PSP blobs failed due to a differing root key. The authors discovered flawed firmware from AMD and have submitted a fix request. Finally, using official firmware from the Turin PI package achieved successful booting.