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KDE Yocto Demo Setup for FOSDEM 2023

This page provides the basic information about the demo setup that is available at the KDE stall at FOSDEM 2023.

What can I see there?

  • a VisionFive-2 RISC-V development board
  • a small HDMI screen
  • a very basic KDE Plasma Bigscreen Session running with a few applications

What is this demo setup about to present?

  • show the state of the Yocto meta-layers: read mere at https://community.kde.org/Yocto
  • show the extremely-WIP state of the hardware porting to the RISC-V board (Kernel, drivers, graphics system and multimedia libraries are all moving targets with big patch sets)
  • give an example of how such embedded boards can be used


  1. Why is the cool, Plasma Bigscreen adapted Aura Browser not running on the demo setup?
    • QtWebEngine in Qt5 does not work with RISC-V (fails to build)
    • there are recent patches from a few months ago to Chromium, which will make the Qt6 version available on the platform
  2. Why is Plank Player not playing videos?
    • Because binary VPU drivers are a mess ;) There is active work-in-progress work to get a fully HW accelerated GStreamer Pipeline running, but though it is close to working, we are not there yet
    • un-accelerated video looks okay though, but due to bugs in the QtMultimedia/GStreamer integration this does not work with Plank at the moment and priority for fixing this in Qt5 is very low on our side
  3. Why does the board not really come back when I press the power-off button?
    • hibernation support just was integrated in the last Kernel update 2 weeks ago, userland integration is an upcoming topic



  • Processor: StarFive JH7110 64bitSoC, up to 1.5GHz
  • Memory: 8GB RAM
  • Storage: see SD card at side
  • Video output: HDMI 2.0 in use (MIPI-DSI untested)
  • GPU: PowerVR (binary Kernel blob driver, binary GLES driver, EGL via MESA)
  • Multimedia
    • WAVE420l encoder chip for H.265
    • WAVE511 decoder chip for H.264 & H.265
    • CodaJ12 encoder/decoder for JPEG


  • running Yocto Langdale
  • meta-riscv patch set for VisionFive2
  • using meta-kf5 and meta-kde in latest versions (Plasma being 5.26.4)

Demo Troubleshooting

  • next to the USB-C power cable, there is a reset button; press it when being in trouble ;)
  • remote control has TWO modes which can be switched by the mouse-cursor button
    1. first mode: controller is behaving like a keyboard with arrow keys, enter button (OK), escape button (with return symbol)
    2. second mode: by moving the remote control relatively to the USB connector in the board, you can move the mouse cursor, press on (OK) is a mouse click
  • if anybody presses the power-off button, do a hard reset (the GPU driver is not coming back correctly yet)