I always wondered how we got there. The original ARM chips, as in the Archimedes era, obviously ran in things that broadly resembled the other desktop computin

I always wondered how we got there. The original ARM chips, as in the Archimedes era, obviously ran in things that broadly resembled the other desktop computing platforms of the era. They had to solve the same problems: deciding which device to boot from, how to initialize the attached grab-bag of peripherals. They also had a long series of models with varying capabilities and integration. So they must have something comparable to a BIOS/EFI/Open Firmware-- a standardized hardware enumeration and bringup process. Somehow that disappeared when ARM moved away from RISC OS "desktop computers" and went into the microcontroller world. Why? I figured it probably either had to do with licensing, or an assumption that an embedded ARM core in some random device would only ever be used with a particular bag of peripherals, so there was no need to rely on conventions.