HDMI over armStoneA9r3

    Hello,


    I try the F&S SD Yocto 2022.09 & F&S SD Yocto 2024.04


    In both Yoctos the Weston Wayland Compositor starts perfectly but I don't receive any HDMI signal.


    Is it possible that by default the devicetree is not configured for HDMI output? How can I enable HDMI output?


    Thanks.

    By default only a Parallel-RGB display is active. You have to change a few device tree macros to switch to HDMI. In arch/arm/boot/dts/armstonea9r3q.dts (quad core) or armstonea9r3dl.dts (single/dual core) there are some comments with instructions of how to configure the displays. In the easiest way you simply need to change CONFIG_ARMSTONEA9R3_MXCFB0 from DISPLAY_LCD to DISPLAY_HDMI (and of course recompile and reinstall the device tree).


    Most customers only need one display. If we activated several displays in parallel, the framebuffers would also be set up and the display data would be transferred to the (non-existent) displays nonetheless, causing quite a lot of load on the system bus and increasing the power usage. And most users would not even be aware of this.


    Your F&S Support Team

    F&S Elektronik Systeme GmbH
    As this is an international forum, please try to post in English.
    Da dies ein internationales Forum ist, bitten wir darum, Beiträge möglichst in Englisch zu verfassen.