iCE40 Open Source Toolchain

This is a compilation of various sources to create a "how to" build a toolchain environment based on open source using Linux/Ubuntu 20.04 LTS distro.

This step-by-step guideline aims to build an open source toolchain for iCE40 series FPGA including:

• IceStorm Tools
  • Arachne-PNR
  • NextPNR
  • Yosys
• icesprog
• RISC-V toolchain

This is fully based on Clifford's Project IceStorm, and inspired on James Devine's Blog.

FTDI drivers

Get the FTDI driver from FTDI chip website, or just follow the next command line block:

mkdir ftdi
cd ftdi
wget https://www.ftdichip.com/Drivers/D2XX/Linux/libftd2xx-x86_64-1.4.8.gz
tar xfvz libftd2xx-x86_64-1.4.8.gz
cd release/build/
sudo -s 
cp libftd2xx.* /usr/local/lib
chmod 0755 /usr/local/lib/libftd2xx.so.1.4.8
ln -sf /usr/local/lib/libftd2xx.so.1.4.8 /usr/local/lib/libftd2xx.so
exit
cd ../../..

Preps

Other packages needed to get things done in Ubuntu:

sudo apt install build-essential clang bison flex libreadline-dev \
                 gawk tcl-dev libffi-dev git mercurial graphviz \
                 xdot pkg-config python python3 libftdi-dev \
                 qt5-default python3-dev libboost-all-dev cmake libeigen3-dev

If you are running Ubuntu 22.04, maybe you have to install g++-12:

sudo apt install g++-12

IceStorm toolchain

This is get from Clifford, go the that page or follow the commands described next.

IceStorm tools

Install the IceStorm Tools (icepack, icebox, iceprog, icetime, chip databases):

git clone https://github.com/YosysHQ/icestorm.git icestorm
cd icestorm
git checkout 83b8ef9
make -j$(nproc)
sudo make install
cd ..

Arachne-PNR

Install Arachne-PNR (place & route tool, predecessor to NextPNR):

git clone https://github.com/cseed/arachne-pnr.git arachne-pnr
cd arachne-pnr
git checkout c40fb22
make -j$(nproc)
sudo make install
cd ..

NextPNR

Install NextPNR (place & route tool, Arachne-PNR replacement):

git clone https://github.com/YosysHQ/nextpnr nextpnr
cd nextpnr
git checkout bd137a8b
cmake -DARCH=ice40 -DCMAKE_INSTALL_PREFIX=/usr/local .
make -j$(nproc)
sudo make install
cd ..

The GUI is not built by default in nextpnr. Add -DBUILD_GUI=ON to the cmake command line, and make sure qt5-default is installed.

Yosys

Install Yosys (Verilog synthesis):

git clone https://github.com/YosysHQ/yosys.git yosys
cd yosys
git checkout 62739f7b
make -j$(nproc)
sudo make install
cd ..

Verify whether the IceStorm toolchain works

To double check everything is fine so far, let's test the setup.
Here, I used the hardware kit iCESugar-nano v1.2 (featuring the iCE40LP1K-CM36 chip).

Connect the hardware board to the computer's USB and try the blink demo from wuxx.

The folder is the https://github.com/wuxx/icesugar-nano/tree/main/src/basic/blink.

git clone https://github.com/wuxx/icesugar-nano
cd icesugar-nano/src/basic/blink
git checkout c45b20b
make build
make prog_flash
cd ../../../..

Hopefully, the orange LED in the iCESugar-nano should blink.
The prog_flash option copies the .bin file to the iCELink folder in the the USB-based mass storage device created once the iCESugar-nano is pluged in the computer.

icesprog

This program is used to flash or do more configs (see the help icesprog -h).
Make sure your iCESugar-nano is connected to the USB.
Do the following:

sudo apt install libhidapi-dev
sudo apt install libusb-1.0-0-dev
git clone https://github.com/wuxx/icesugar.git icesugar
cd icesugar/tools/src/
git checkout c45b20b
make
sudo cp icesprog /usr/local/bin/.
icesprog -p 
cd ../../..

with the last command, you should see:

probe chip
board: [iCESugar-Nano]
flash: [w25q16] (2MB)
done

RISC-V toolchain

Install the Clifford Wolf's Picorv32.

git clone https://github.com/cliffordwolf/picorv32 picorv32

sudo apt install autoconf automake autotools-dev curl libmpc-dev \
         libmpfr-dev libgmp-dev gawk build-essential bison flex texinfo \
         gperf libtool patchutils bc zlib1g-dev git libexpat1-dev

sudo mkdir /opt/riscv32i
sudo chown $USER /opt/riscv32i

git clone https://github.com/riscv/riscv-gnu-toolchain riscv-gnu-toolchain-rv32i
cd riscv-gnu-toolchain-rv32i
git checkout 411d134
git submodule update --init --recursive

mkdir build
cd build
../configure --with-arch=rv32i --prefix=/opt/riscv32i
make -j$(nproc)
cd ../..

Femto SoC RV32 (work in progress)

Follow the next command line to have your Femto SoC RV32 synthesis, PnR, and bitstream femtosoc.bin for iCESugar-nano v1.2. This step is originally from Bruno Levy, but we use the modifications as in here.

sudo apt install python3-serial
git clone https://github.com/dloubach/femtorv32.git femtorv32
cd femtorv32/FemtoRV/
make icesugar_nano

iCESugar-nano hw board	nextpnr running
Featuring FPGA iCE40LP1K-CM36	Logic Cells (LUT + FF) utilization: 1,248/1,280 (97%)

iCESugar-nano Block Diagram