/dev/verdin-uart1 does not exist

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It looks like you are trying to enable UART1 on the Verdin AM62 module, but the device node /dev/verdin-uart1 is not appearing. Here are a few steps to troubleshoot and ensure that your device tree overlay is correctly enabling UART1:

  1. Check the UART Alias:
    Ensure that the alias for UART1 is correctly defined in the base device tree. Typically, UART aliases are defined in the aliases node. For example:

    / {
    aliases {
        serial0 = &main_uart1;
    };
};

  2. Verify the UART Node:
    Make sure that the main_uart1 node is correctly defined in the base device tree and that it has the correct properties. For example:

    &main_uart1 {
    compatible = "ns16550a";
    reg = <0x0 0x0>;
    interrupts = <0x0 0x0>;
    status = "okay";
};

  3. Check the Overlay Application:
    Ensure that your overlay is correctly applied. You can check the boot log to see if the overlay is being applied without errors. Look for messages related to device tree overlays in the boot log.

  4. Verify the Device Node Creation:
    After booting, check the kernel log (dmesg) for any messages related to UART. This can provide clues if there are issues with the UART driver or device tree.

  5. Check the Device Tree Compilation:
    Ensure that your device tree overlay is correctly compiled into a .dtbo file. You can manually compile it using the dtc command:

    dtc -I dts -O dtb -o verdin-am62_best_bsample.dtbo verdin-am62_best_bsample.dts

  6. Update the overlays.txt:
    Ensure that the overlays.txt file in the boot partition includes your overlay:

    fdt_overlays=verdin-am62_best_bsample.dtbo

  7. Check the U-Boot Environment:
    Ensure that U-Boot is correctly loading the overlays. You can check the U-Boot environment variables related to device tree overlays:

    printenv fdt_overlays

  8. Verify the Device Node in /dev:
    After booting, check the /dev directory for the UART device node. It might not be named /dev/verdin-uart1. It could be named something like /dev/ttyS0 or /dev/ttyS1.

If you have verified all the above steps and the issue persists, there might be a problem with the specific device tree bindings or the UART driver. In that case, you might need to refer to the specific documentation for the Verdin AM62 module or reach out to Toradex support for further assistance.

Please, also check if these links can help you solve your problem:

Adding custom overlays to Yocto image.