Riscy-SoC

Riscy-SoC is SoC based on RISC-V CPU core, previously designed in SystemVerilog, but has been adapted to Verilog because current open-source tools dont support SystemVerilog.

This is a re-work of the Icicle CPU, so that it supports 64 bit version and works with open-source tools like APIO.

About the core

The RISC-V core is RV64I compatible CPU with classic RISC 5-stage pipeline.

It has shared instruction and data memory (which is 8KiB in this case).

How to build

Prerequisite: Yosys, IceStorm and NextPnR. You can build it for Lattice iCE 40 family of FPGA's using yosys synthesis in the tool the following way:

git clone https://github.com/AleksandarKostovic/Riscy-SoC.git
cd Riscy-SoC/rtl/cpu

yosys -p 'synth_ice40 -top top -json top.json' top.v               # syntesize into top.json | currently fails but will be fixed
nextpnr-ice40 --hx1k --json top.json --pcf top.pcf --asc top.asc   # run place and route
icepack top.asc top.bin                                            # generate binary bitstream file

After you have created a bitstream for FPGA, ran place and route, you can use whatever bootloader/programmer you have for your FPGA board. If you use TinyFPGA, ICEbreaker or Arty-7, you can use TinyProg to upload the bitstream.

tinyprog -p top.bin