Flashrom reports an unsupported chipset. See below and the attached file for a lspci report. Motherboard is an ASRock Taichi x370 with a AMD 5900X processor.
# flashrom --programmer internal flashrom v1.2 on Linux 5.17.14-gentoo-x86_64 (x86_64) flashrom is free software, get the source code at https://flashrom.org
Using clock_gettime for delay loops (clk_id: 1, resolution: 1ns). Found chipset "AMD FP4". Enabling flash write... FCH device found but SMBus revision 0x61 does not match known values. Please report this to email@example.com and include this log and the output of lspci -nnvx, thanks!. Could not determine chipset generation.PROBLEMS, continuing anyway No EEPROM/flash device found. Note: flashrom can never write if the flash chip isn't found automatically.
-- Adrien Dessemond