Flashing firmware internally
WARNING: If you flash a broken firmware and have no recovery mechanism, you must use the external method to flash a working firmware again.
Using flashrom
This method does only work on Linux, if it isn’t locked down.
You may also need to boot with iomem=relaxed
in the kernel command
line if CONFIG_IO_STRICT_DEVMEM is set.
For more details please also check flashrom’s wiki. Use the programmer internal to flash coreboot.rom internally:
flashrom -p internal -w coreboot.rom