RISC-V Extensions

A portfolio of RISC-V extensions, custom instruction sets for domain specific acceleration and applications. The extensions are first built in the riscv toolchain and simulator then reverse engineered as patch files for portability between systems.

Tools

• RISCV GNU Toolchain
• RISCV ISA Simulator - Spike
• RISCV PK

Installation

Because of the custom nature of RISC-V extensions, installation may look different between different systems. Below is an example of the directory structure I use for my RISC-V extension development.

1. Create a parent directory called 'RISCV'
2. Create a sub directory called 'riscv-dev' (this holds tools cross compilation files from make)
3. Clone the tools listed above into the RISCV directory
   • For the toolchain, spike, and pk use riscv-dev as the '--prefix' path
4. Clone this extension repository into RISCV
5. Traverse into the extension to be added and run the apply_patches.sh script in its patches directory