Flashing coreboot using SMC IPMI (BMC) firmware¶
In order to flash anything to the “BIOS” IC, it needs to contain a valid BIOSINFO struct.
The BIOSINFO struct contains a
$FID marker at the beginning and is
128 bytes in total. Besides the BoardID it contains the firmware version
and build date. The BMC verifies that the BoardID is correct and refuses to
flash if it’s not.
The struct has no checksum or cryptographic protection.
The smcinfobios tool¶
The smcbiosinfo tool can be found in
It parses the
build/build.h header to get the current coreboot version and
The board ID is passed as command line argument.
It will place a file in CBFS called
smcbiosinfo.bin, which is then found
by the vendor tools. The file contains the struct described above.
Flashing using SMCIPMItool¶
You can use the SMCIPMITool to remotely flash the BIOS:
SMCIPMITool <remote BMC IP> <user> <password> bios update build/coreboot.rom
Make sure that the ME isn’t in recovery mode, otherwise you get an error message on updating the BIOS.