SCARV: processor core implementation

Acting as a component part of the wider SCARV project, the RISC-V compatible SCARV micro-controller (comprising a processor core and SoC) is the eponymous, capstone output, e.g., representing a demonstrator for the research oriented XCrypto ISE and the industry oriented RISC-V Scalar Cryptography ISE. The main repository acts as a general container for associated resources; this specific submodule houses the processor core implementation.

Branches:

• master - Main branch for XCrypto related work.
• riscv/crypto-ise - Main branch for RISC-V Crypto ISE implementation.
• scarv/skywater/main - Main branch for Skywater tapeout project.
• dev/paper/aes-n-ways - Development branch for RISC-V AES ISE Evaluation.
• scarv/xcrypto/masking-ise - Development branch for Software masking ISE.

Contents:

• Overview
• Documentation
• Quickstart
• Acknowledgements

Overview

This is a 5-stage single issue in order CPU core, implementing the RISC-V 32-bit integer base architecture, along with the Compressed and Multiply extensions. It's a micro-controller, with no cache, branch prediction or virtual memory.

Documentation

See the docs/ folder for information on the design requirements and the pipeline structure.

• Design Requirements
• Functional Verification
• Implementation Documentation:
  • Instruction Table
  • Pipeline Structure
  • Leakage Fence Instruction Implementation
  • Random Number Generator Interface

Quickstart

• Install the following tools installed to use all parts of the design flow:

  • Verilator

  • Yosys

  • SymbiYosys

  • A Toolchain which supports the XCrypto instruction set extension.

• Checkout the repository and required submodules.

  $> git clone [email protected]:scarv-cpu/scarv-cpu.git
  $> cd scarv-cpu/
  $> git submodule update --init --remote

• Setup tool environment variables.

  $> export YOSYS_ROOT=<path to yosys installation>
  $> export RISCV=<path to toolchain installation>

• Configure the project environment.

  $> source bin/conf.sh

• Build the verilator simulation model:

  $> make verilator_build

• Run the basic RISC-V compliance tests:

  $> make riscv-compliance-build
  $> make riscv-compliance-run

• Run the standard Yosys Synthesis flow:

  $> make synthesise

Acknowledgements

This work has been supported in part by EPSRC via grant EP/R012288/1, under the RISE programme.