Help with accessing devices. #1
Description
https://github.com/mschwartz/amos
You are free to copy and paste from the sources. The boot loader is not UEFI, but the repo contains a lot of low level device drivers. Keyboard, screen/text/graphics, hard disk, timers, and so on. You can see the hardware addresses and strategies for their use in the code.
The bootloader does some useful things like setting up the processor in 64 bit mode, setup of the MMU, etc.