How to enable MCUboot serial log with USB DFU setup?

RE: How to enable MCUboot serial log with USB DFU setup?

narangmayank — Wed, 19 Mar 2025 06:33:35 GMT

I have a similar use case with a little twaek, We have only nRF USB interface in our custom hardware. I have managed to do DFU via the same USB. Now as a next step I want to emulate 2 CDC ACM instance of the same in the mcuboot so 1 will be used for DFU and other will be used for mcuboot logs.

I tried below conf but it didn't worked out,

mcuboot conf

CONFIG_MCUBOOT_SERIAL=y
CONFIG_BOOT_SERIAL_UART=n
CONFIG_BOOT_SERIAL_CDC_ACM=y
CONFIG_UART_CONSOLE=y

mcuboot overlay

/ {
	chosen {
		zephyr,console = &cdc_acm_uart0;
		zephyr,uart-mcumgr = &cdc_acm_uart1;
	};
};

&zephyr_udc0 {
	cdc_acm_uart0: cdc_acm_uart0 {
		compatible = "zephyr,cdc-acm-uart";
		label = "CDC_ACM_0";
	};

	cdc_acm_uart1: cdc_acm_uart1 {
		compatible = "zephyr,cdc-acm-uart";
		label = "CDC_ACM_1";
	};
};

Any idea how to do this?

Thanks for any help.

RE: How to enable MCUboot serial log with USB DFU setup?

Saxman58 — Tue, 11 Feb 2025 18:14:57 GMT

Thanks once again, Sigurd. I had tried the chosen settings before to set just the console to the UART, assuming the mcumgr would stay on the USB, but then get compiler errors. I finally got it to work by being explicit about where to connect each of them with this in the mcuboot.overlay file:

/ {
    chosen {
        zephyr,uart-mcumgr = &usbd;
        zephyr,console = &uart0;
    };
};

...and this in the mcuboot.conf file:

# Support DFU over USB serial, but not UART.  UART used for logs (console).
CONFIG_MCUBOOT_SERIAL=y
CONFIG_BOOT_SERIAL_UART=n
CONFIG_BOOT_SERIAL_CDC_ACM=y
CONFIG_UART_CONSOLE=y

Thus both files were more explicit about wanting the logs on the UART and the mcumgr/DFU on the USB port. Now I can see both the bootloader and app logs in the terminal.

RE: How to enable MCUboot serial log with USB DFU setup?

Sigurd Hellesvik — Tue, 11 Feb 2025 14:36:19 GMT

Hi,

See here: https://github.com/nrfconnect/sdk-mcuboot/blob/3c2f2ff12bc20625cd65730b6036d061de4da5f7/boot/zephyr/Kconfig.serial_recovery#L32-L36.

Looks like you should be able to use chosen "zephyr,uart-mcumgr" for SMP and "zephyr,console" for logs as is done for the application also.

Regards,
Sigurd Hellesvik