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SiFive Freedom E SDK README

This repository, maintained by SiFive Inc, makes it easy to get started developing software for the Freedom E and Freedom S Embedded RISC-V Platforms. This SDK is intended to work on any target supported by SiFive's distributions of the RISC-V GNU Toolchain.

Documentation for Freedom E SDK is available here

Freedom E SDK was recently transitioned to using the Freedom Metal compatibility library. If you're looking for the old Freedom E SDK, software examples, and board support files, you can find those on the v1_0 branch.

What is Freedom Metal?

Freedom Metal (Documentation) is a library developed by SiFive for writing portable software for all of SiFive's RISC-V IP, RISC-V FPGA evaluation images, and development boards. Programs written against the Freedom Metal API are intended to build and run for all SiFive RISC-V targets. This makes Freedom Metal suitable for writing portable tests, bare metal application programming, and as a hardware abstraction layer for porting operating systems to RISC-V.

Contents

Freedom Metal Compatibility Library

Setting up the SDK

Prerequisites

To use this SDK, you will need the following software available on your machine:

Install the RISC-V Toolchain and OpenOCD

The RISC-V GNU Toolchain and OpenOCD are available from the SiFive Website at

https://www.sifive.com/boards

For OpenOCD and/or RISC-V GNU Toolchain, download the .tar.gz for your platform, and unpack it to your desired location. Then, use the RISCV_PATH and RISCV_OPENOCD_PATH variables when using the tools:

cp openocd-<date>-<platform>.tar.gz /my/desired/location/
cp riscv64-unknown-elf-gcc-<date>-<platform>.tar.gz /my/desired/location
cd /my/desired/location
tar -xvf openocd-<date>-<platform>.tar.gz
tar -xvf riscv64-unknown-elf-gcc-<date>-<platform>.tar.gz
export RISCV_OPENOCD_PATH=/my/desired/location/openocd
export RISCV_PATH=/my/desired/location/riscv64-unknown-elf-gcc-<date>-<version>
Install RISC-V QEMU 4.1.0

The RISC-V QEMU Emulator is available from the SiFive Website at

https://www.sifive.com/boards

Download the .tar.gz for your platform and unpack it to your desired location. Then, add QEMU to your path:

cp riscv-qemu-<version>-<date>-<platform>.tar.gz /my/desired/location
tar -xvf riscv-qemu-<version>-<date>-<platform>.tar.gz
export PATH=$PATH:/my/desired/location/riscv-qemu-<version>-<date>-<platform>/bin
Install Segger J-Link Software

Some targets supported by Freedom E SDK (like the SiFive HiFive1 Rev B) use Segger J-Link OB for programming and debugging. If you intend to use these targets, install the Segger J-Link Software and Documentation Pack for your machine:

Segger J-Link Software Downloads

Cloning the Repository

This repository can be cloned by running the following commands:

git clone --recursive https://github.com/sifive/freedom-e-sdk.git
cd freedom-e-sdk

The --recursive option is required to clone the git submodules included in the repository. If at first you omit the --recursive option, you can achieve the same effect by updating submodules using the command:

git submodule update --init --recursive

Updating your SDK

If you'd like to update your SDK to the latest version:

git pull origin master
git submodule update --init --recursive

Using the Tools

Building an Example

To compile a bare-metal RISC-V program:

make [PROGRAM=hello] [TARGET=sifive-hifive1] [CONFIGURATION=debug] software

The square brackets in the above command indicate optional parameters for the Make invocation. As you can see, the default values of these parameters tell the build script to build the hello example for the sifive-hifive1 target with the debug configuration. If, for example, you wished to build the timer-interrupt example for the S51 Arty FPGA Evaluation target, with the release configuration, you would instead run the command

make PROGRAM=timer-interrupt TARGET=coreip-s51-arty CONFIGURATION=release software
Building an Benchmark Program

Building a benchmark program is slightly special in that certain section is required to be loaded in specific memory region. A specialize linker file has been created for its optimal run.

make PROGRAM=dhrystone TARGET=coreip-e31-arty LINK_TARGET=ramrodata software

Uploading to the Target Board

make [PROGRAM=hello] [TARGET=sifive-hifive1] [CONFIGURATION=debug] upload

Debugging a Target Program

make [PROGRAM=hello] [TARGET=sifive-hifive1] [CONFIGURATION=debug] debug

Cleaning a Target Program Build Directory

make [PROGRAM=hello] [TARGET=sifive-hifive1] [CONFIGURATION=debug] clean

Create a Standalone Project

You can export a program to a standalone project directory using the standalone target. The resulting project will be locked to a specific TARGET. Note that this functionality is only supported for Freedom Metal programs, not the Legacy Freedom E SDK.

STANDALONE_DEST is a required argument to provide the desired project location.

make [PROGRAM=hello] [TARGET=sifive-hifive1] [INCLUDE_METAL_SOURCES=1] STANDALONE_DEST=/path/to/desired/location standalone

Run make help for more commands.

For More Information

Documentation, Forums, and much more available at

dev.sifive.com