tillitis-key/doc/toolchain_setup.md

Toolchain setup

Here are instructions for setting up the tools required to build the project. Tested on Ubuntu 22.10.

Gateware: icestorm toolchain

These steps are used to build and install the icestorm toolchain (in /usr/local). Note that nextpnr replaces Arachne-PNR.

sudo apt install build-essential clang lld llvm bison flex libreadline-dev \
                 gawk tcl-dev libffi-dev git mercurial graphviz \
                 xdot pkg-config python3 libftdi-dev \
                 python3-dev libeigen3-dev \
                 libboost-dev libboost-filesystem-dev \
                 libboost-thread-dev libboost-program-options-dev \
                 libboost-iostreams-dev cmake libhidapi-dev \
                 ninja-build libglib2.0-dev libpixman-1-dev \
                 golang

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

# Custom iceprog for the RPi 2040-based programmer (will be upstreamed).
git clone -b interfaces https://github.com/tillitis/icestorm tillitis--icestorm
cd tillitis--icestorm/iceprog
make
sudo make PROGRAM_PREFIX=tillitis- install
cd ../..

git clone https://github.com/YosysHQ/yosys
cd yosys
# Avoiding current issue with yosys & icebram, filed in:
# https://github.com/YosysHQ/yosys/issues/3478
git checkout 06ef3f264afaa3eaeab45cc0404d8006c15f02b1
make -j$(nproc)
sudo make install
cd ..

git clone https://github.com/YosysHQ/nextpnr
cd nextpnr
# Use nextpnr-0.4. Aa few commits later we got issues, like on f4e6bbd383f6c43.
git checkout nextpnr-0.4
cmake -DARCH=ice40 -DCMAKE_INSTALL_PREFIX=/usr/local .
make -j$(nproc)
sudo make install

References:

• http://bygone.clairexen.net/icestorm/

Firmware: riscv toolchain

The Tillitis Key 1 implements a picorv32 soft core CPU, which is a RISC-V microcontroller with the M and C instructions (RV32IMC). You can read more about it.

The project uses the LLVM/Clang suite, where version 14 is the latest stable (as of writing). Usually the LLVM/Clang packages that are part of your distro will work, if not, there are installations instructions for "Install (stable branch)" at https://apt.llvm.org/ for Debian and Ubuntu.

References:

• https://github.com/YosysHQ/picorv32

Optional

These tools are used for specific sub-components of the project, and are not required for general development

Kicad 6.0: Circuit board designs

The circuit board designs were all created in KiCad 6.0.

mta1-usb-v1-programmer: RPi 2040 toolchain

These tools are needed to build the programmer firmware for the mta1-usb-v1-programmer

FW update of programmer board

The programmer board is running a custom firmware developed by Blinkinlabs. The source code for this firnware is available on Github: https://github.com/Blinkinlabs/ice40_flasher

There is also a pre built firmware binary available for the programmer board: https://github.com/Blinkinlabs/ice40_flasher/tree/main/bin

To update the firmware on the programmer board, either build the file "main.uf2", or download the pre built file to your host computer. Then do the following:

1. Disconnect the programming board from the host computer
2. Press and hold the "BOOTSEL" button on the RPi2040 sub board on the programming board
3. Reconnect the programming board to the host computer
4. Release the "BOOTSEL" button after connecting the programming board to the host. The board should now appear to the host as a USB connected storage device
5. Open the storage device and drop the firmware file ("main.uf2") into the storage device

The programmer will update its firmware with the file and restart itself. After reboot the storage device will automatically be disconnected.

mta1-usb-v1: ch552 USB to Serial firmware

The USB to Serial firmware runs on the CH552 microcontroller, and provides a USB CDC profile which should work with the default drivers on all major operating systems.

TODO

References:

• source code: https://github.com/tillitis/tillitis-key1/tree/main/hw/boards/mta1-usb-v1/ch552_fw
• Compiler: SDCC
• Library: https://github.com/Blinkinlabs/ch554_sdcc
• Flashing tool: https://github.com/ole00/chprog