Haleigh Novak wrote:
I was wondering if anyone could take a few minutes and explain the proccess of how coreboots SeaBIOS payload (or even how coreboot itself) transitions into a Linux boot sequence to me?
SeaBIOS does nothing coreboot-specific, but uses the de-facto standard BIOS method: Master Boot Record
In the MBR there is code installed by the bootloader in use (LILO/NTLDR/GRUB/SYSLINUX/etc)
See wikipedia.org and osdev.org for all MBR details you may want.
Writing a small assembly program to run out of the MBR is a great exercise.
When coreboot instead starts a Linux kernel directly (with Linux as payload) then the key word is: SELF
SELF is Simple ELF, and when cbfstool adds a kernel payload to coreboot.rom it also adds a small stub code at the entry point, which sets up the data structure in memory which Linux requirs to boot on x86, before jumping to the kernel entry point.
//Peter