vriscv - a risc-v simulator

Resources used

Juraj's Blog, mostly:

• https://jborza.com/post/2021-04-04-riscv-supervisor-mode/
• https://jborza.com/emulation/2021/04/22/ecalls-and-syscalls.html

Buildroot fork for nommu linux:

• https://github.com/regymm/buildroot