Am Samstag, den 02.09.2017, 12:36 +0000 schrieb Peter Stuge:
Sure, but a payload can. SeaBIOS aims to provide a complete BIOS with all neccessary interrupt services for legacy compatibility.
Once coreboot jumped into SeaBIOS-code the latter is responsible for providing the right interface for interrupt services.
I guess it doesn't matter very much in the end who switches the CPU to Real Mode. My point is that coreboot's bios calls can't be called because they don't exist ^^
That depends. A *payload* can not assume interrupt services, but a bootloader (e.g. in MBR) can very well assume interrupt services, especially since MBR is a BIOS paradigm.
Every payload built for and with coreboot won't try to call interrupts.
And you can't use the 32-Bit-Instructionset anymore, can you?
That's orthogonal. You can use 32-bit instructions in 16-bit mode and vice versa. The 0x66 and 0x67 opcode prefixes can be used to set an instruction mode for a single instruction.
But in the beginning of this thread on 02 Aug Ron Minnich wrote that coreboot switches to PM, because:
"And we want the 32-bit instruction set."