42 lines
1.3 KiB
Markdown
42 lines
1.3 KiB
Markdown
# A simple RISC-V emulator
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This is a toy emulator for RISC-V, made for educational purposes.
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The goal is to have a base rv32i instruction set (the bare minimum) plus a M-extension for division and multiplication. In theory, it should be enough to execute simple C programs compiled with GCC and sprinkled with a few linker scripts. Of course, no libc because there's no OS.
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## Compiling and running
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You'd need [nix package manager](https://nixos.org/) in order to build the project. This is because installing cross-toolchain to compile an example project is difficult, and I don't know of other ways except nix that make it easy.
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If you don't have it, install it like this:
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```sh
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curl --proto '=https' --tlsv1.2 -sSf -L https://install.determinate.systems/nix | sh -s -- install
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```
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Now, to build the emulator:
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```sh
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nix develop
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eval "$configurePhase"
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ninja
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```
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As a result you should get an executable called `rve`
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## Cross-toolchain and an example program in C
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There is an example program which you can compile. It requires some custom toolchain so currently not built with CMake. To compile it:
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```sh
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cd example
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make
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```
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As a result, you'll get an `example.raw` binary. To execute it:
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```sh
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./rve ../example/example.raw
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```
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The expected output of the example program is `40320`.
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