Freedom

This repository contains the RTL created by SiFive for its Freedom E300 and U500 platforms. The Freedom E310 Arty FPGA Dev Kit implements the Freedom E300 Platform and is designed to be mapped onto an Arty FPGA Evaluation Kit. The Freedom U500 VC707 FPGA Dev Kit implements the Freedom U500 Platform and is designed to be mapped onto a VC707 FPGA Evaluation Kit. Both systems boot autonomously and can be controlled via an external debugger.

Run the following commands to clone the repository and get started:

$ git clone https://github.com/sifive/freedom.git
$ cd freedom

#Run this command to update subrepositories used by freedom
$ git submodule update --init --recursive

Next, read the section corresponding to the kit you are interested in for instructions on how to use this repo.

Software Requirement

To compile the bootloaders for both Freedom E300 Arty and U500 VC707 FPGA dev kits, the RISC-V software toolchain must be installed locally and set the $(RISCV) environment variable to point to the location of where the RISC-V toolchains are installed. You can build the toolchain from scratch or download the tools here: https://www.sifive.com/products/tools/

After installing toolchain and vivado, you must set the environment variables.

If you have installed toolchain to /home/riscv/riscv64-elf-tc/bin/riscv64-unknown-elf-gcc then run the following command. Do not include /bin at the end of the string.

$ export RISCV=/home/riscv/riscv64-elf-tc

In order to run the mcs target in the next step, you need to have the vivado executable on your PATH.

If vivado is installed to /tools/Xilinx/Vivado/2016.4/bin, you can set the PATH with the following command.

$ export PATH=${PATH}:/tools/Xilinx/Vivado/2016.4/bin

Change the line above if the vivado is installed to /opt/Xilinx/Vivado/2016.4/bin accordingly.

Freedom E300 Arty FPGA Dev Kit

The Freedom E300 Arty FPGA Dev Kit implements a Freedom E300 chip.

How to build

The Makefile corresponding to the Freedom E300 Arty FPGA Dev Kit is Makefile.e300artydevkit and it consists of two main targets:

• verilog: to compile the Chisel source files and generate the Verilog files.
• mcs: to create a Configuration Memory File (.mcs) that can be programmed onto an Arty FPGA board.

To execute these targets, you can run the following commands:

$ make -f Makefile.e300artydevkit verilog
$ make -f Makefile.e300artydevkit mcs

Note: This flow requires Vivado 2017.1. Old versions are known to fail.

These will place the files under builds/e300artydevkit/obj.

Bootrom

The default bootrom consists of a program that immediately jumps to address 0x20400000, which is 0x00400000 bytes into the SPI flash memory on the Arty board.

Using the generated MCS Image

For instructions for getting the generated image onto an FPGA and programming it with software using the Freedom E SDK, please see the Freedom E310 Arty FPGA Dev Kit Getting Started Guide.

Freedom U500 VC707 FPGA Dev Kit

The Freedom U500 VC707 FPGA Dev Kit implements the Freedom U500 platform.

How to build

The Makefile corresponding to the Freedom U500 VC707 FPGA Dev Kit is Makefile.vc707-u500devkit and it consists of two main targets:

• verilog: to compile the Chisel source files and generate the Verilog files.
• mcs: to create a Configuration Memory File (.mcs) that can be programmed onto an VC707 FPGA board.

To execute these targets, you can run the following commands:

$ make -f Makefile.vc707-u500devkit verilog
$ make -f Makefile.vc707-u500devkit mcs

Note: This flow requires Vivado 2016.4. Newer versions are known to fail.

These will place the files under builds/vc707-u500devkit/obj.

Bootrom

The default bootrom consists of a bootloader that loads a program off the SD card slot on the VC707 board.

Linux boot Image

The bootable Linux image for vc707 is able to build from the link SD boot image.