dutlink-board firmware

This repository contains the firmware for the dutlink-board project, a project within jumpstarter that enables easy testing and development of SOC/SOM and other systems with Hardware in the Loop.

Jumpstarter is a project designed to enable generic Hardware in the Loop testability for Edge / embedded designs.

Dutlink is based on the STM32F411 microcontroller and the Rust programming language.

The firmware is written in Rust, and it is made of two parts:

• The bootloader, which enables seamless firmware updates via the fwupd project.
• The application, which provides the functionality described in the following sections.

you can find out more about jumpstarter in https://jumpstarter.dev

Flashing Firmware

Quick Start - Using the Flash Script

The easiest way to flash firmware to your DUTLink device is using the provided flash-dutlink.sh script, which automatically downloads the latest release and flashes it to your device.

Prerequisites

• Linux system (the script is designed for Linux)
• Root access (required for dfu-util to access USB devices)
• dfu-util installed on your system
• curl for downloading firmware

Flashing Process

1. Download the flash script:

   wget https://raw.githubusercontent.com/jumpstarter-dev/dutlink-firmware/main/flash-dutlink.sh
   chmod +x flash-dutlink.sh

2. Run the script as root:

   sudo ./flash-dutlink.sh

3. Follow the on-screen instructions:

   • Connect your DUTLink device via USB
   • Put the device in DFU mode:
     • Hold the FACTORY_DFU button
     • Press and release the RESET button
     • Release the FACTORY_DFU button
   • Press Enter when ready

4. Wait for completion:

   • The script will automatically download the latest firmware
   • Flash the bootloader first
   • Then flash the application firmware
   • The device will reset automatically when complete

The script handles the entire flashing process, including downloading the latest release binaries and managing the two-stage flashing process (bootloader + application).

Devel environment

Environment setup

For development environment in this case, we recommend a Fedora machine with the following packages installed:

$ dnf install -y stlink openocd arm-none-eabi-binutils-cs gcab libappstream-glib rpm-build copr-cli dfu-util

# install the community version of rust, and the ARM thumbv7m-none-eaby target
$ curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh
$ source "$HOME/.cargo/env"
$ rustup target add thumbv7m-none-eabi
$ rustup target add thumbv7em-none-eabihf

One hack to install gcab in RHEL9 is:

sudo subscription-manager repos --enable=codeready-builder-for-rhel-9-x86_64-rpms
cd /tmp
dnf download --source libgcab1
sudo dnf builddep libgcab1
sudo dnf install rpm-build
sudo rpmbuild --rebuild libgcab*.src.rpm
sudo dnf install ~/rpmbuild/RPMS/$(uname -m)/gcab* ~/rpmbuild/RPMS/$(uname -m)/libgcab*

Bootloader and Update protocol

The bootloader implements the DFU / DFUse protocols, as fwupd supports these protocols.

DFU defines two interfaces: a bootloader interface that can write, erase, or read (if enabled) the application space, and a runtime interface that allows the host to request the application to jump back to the bootloader.

The DFU protocol is implemented using the usbd-dfu Rust library, which is based on the usb-device stack. We build the bootloaders using the usbd-dfu-example provided by the author.

When the application firmware is running, the applications implement the DFU runtime interface, declaring the device as DFU-enabled and accepting the DFU_DETACH and GET_STATUS commands.

We implement the DFU runtime using the usbd-dfu-rt Rust library, which is based on the usb-device stack.

Description

The DUTLink board communicates with a host via USB, enabling the switching of a USB3 storage device between the DUT and the Test host. This enables very fast storage injection on the DUT, and very fast lifecycles for testing.

In addition DUTLink can control power, provide console access via TX/RX UART, and measure power consumption. See features for a more detailed insight.

Features

• USB Storage sharing

  • A storage device can be connected to the Testing host, and then passed down to the DUT
  • USB3.1 (up to 5Gbps, Do not use 10Gbps devices, we exceed the USB3 spec trace lengths, and the signal is degraded) capable
  • USB3.0 and 2.0 capable for backwards compatibility
  • Storage device power cycling

• DUT Power management:

  • ON/OFF, Reset, Reboot
  • Power consumption measurement and logging in watts
  • 5-25V power supply support
  • USB-PD power supply support 5-20V with DUT power negotiation

• DUT Control (3.3v I/O)

  • UART Serial port TX/RX (for logging and tracing)
  • 4 customizable control signals
  • RESET signal