RISC-V Emulator and Linux System from Scratch

This repo contains all the source code required to follow the blog post at https://werwolv.net/posts/linux_bringup/

Source Code

• /lib contains the entire rv32ima instruction set emulator code as well as a minimal set of emulated devices
• /main contains the configuration for our machine and functions exposed for WebAssembly use

Configuration

All the config files required to build Linux can be found in /boot. The main executable also expects all the built binaries to be in the boot folder.

• riscv32-unknown-linux-gnu.config is the crosstool-ng toolchain config file
• riscv_emulator_defconfig is the Linux Kernel config file
• device_tree.dts is the minimal device tree
  • Can be compiled to a dtb using dtc -I dts -O dtb device_tree.dts -o device_tree.dtb
• init.c is the init program
  • Can be compiled using riscv32-unknown-linux-gnu-gcc -static init.c -o init
• initramfs.txt is the gen_init_cpio config file to generate the initramfs
  • Can be compiled to a cpio using usr/gen_init_cpio initramfs.txt -o initramfs.cpio