Comparing the git trees for the current stock coreboot and for your MrChromebox-4.21, I'm wondering about the .config differences generated by nconfig at CONFIG_FSP_HEADER_PATH=.
./src/soc/intel/apollolake/Kconfig has:
config FSP_HEADER_PATH default "src/vendorcode/intel/fsp/fsp2_0/geminilake/2.2.0.0" if VENDOR_GOOGLE && SOC_INTEL_GEMINILAKE default "src/vendorcode/intel/fsp/fsp2_0/geminilake/2.2.3.1" if SOC_INTEL_GEMINILAKE default "3rdparty/fsp/ApolloLakeFspBinPkg/Include/"
But, "make nconfig" in the MrChromebox tree, nonetheless, produces 'CONFIG_FSP_HEADER_PATH="src/vendorcode/intel/fsp/fsp2_0/geminilake/2.2.3.1"' in the .config, somehow, despite the above, while the stock coreboot "make nconfig" instead produces 'CONFIG_FSP_HEADER_PATH="src/vendorcode/intel/fsp/fsp2_0/geminilake/2.2.0.0"', as might be expected.
Can someone explain why there is the "if VENDOR_GOOGLE && SOC_INTEL_GEMINILAKE" consraint for the fsp?
Is fsp 2.2.3.1 actually still the correct configuration when using the fsp.bin files extracted from the stock Google ChromeOS?
Thanks James