Redirect U-Boot console to UART2 in RPi 4B

Question

This is similar to this question, but for different hardware and with some things already tried. My ultimate goal is to have bluetooth on UART0 and debug on UART2.

I use RPi 4B and need to redirect U-Boot console to UART2. My current setup:

I configured force_eeprom_read=0 and disable_poe_fan=1 in my config.txt as described here.
For now I also have dtoverlay=disable-bt and enable_uart=1 in config.txt.
I configured dtoverlay=uart2 in my config.txt

I prepared (and applied in config.txt) an overlay to pick uart2 in /chosen node:

/dts-v1/;
/plugin/;
/{
        compatible = "brcm,bcm2711";
    fragment@0 {   
            target-path = &quot;/chosen&quot;;
            __overlay__ {
                    /* uart2 */
                    stdout-path = &quot;serial@7e201400:115200n8&quot;;
            };     
    };

};

When I boot the device in this configuration, U-Boot console still points to UART0.

In U-Boot prompt I check serial configuration using coninfo:

U-Boot> coninfo
List of available devices:
serial@7e201000 00000007 IO 
serial   00000003 IO stdin stdout stderr

I can also investigate the /chosen node of device tree:

U-Boot> fdt addr ${fdt_addr}
U-Boot> fdt list /chosen
chosen {
        ranges;
        #size-cells = <0x00000001>;
        #address-cells = <0x00000001>;
        compatible = "simple_bus";
        kaslr-seed = <0xb6f21e2c 0x0dbb17ef>;
        stdout-path = "serial@7e201400:115200n8";
        rpi-boardrev-ext = <0x00000000>;
        bootargs = "...";
        framebuffer@3eaf5000 {
        };
        bootloader {
        };
};

The overlay applied correctly, as I now have stdout-path set to the desired UART.

Further investigating the device tree:

U-Boot> fdt list /soc/serial@7e201400
serial@7e201400 {
        pinctrl-0 = <0x000000a0>;
        pinctrl-names = "default";
        compatible = "arm,pl011", "arm,primecell";
        reg = <0x7e201400 0x00000200>;
        interrupts = <0x00000000 0x00000079 0x00000004>;
        clocks = <0x00000007 0x00000013 0x00000007 0x00000014>;
        clock-names = "uartclk", "apb_pclk";
        arm,primecell-periphid = <0x00241011>;
        status = "okay";
        phandle = <0x000000b2>;
};

This shows that the uart2 overlay was applied correctly. However, this UART is not even shown in the coninfo list.

What do I miss here?

I found the first error: the stdout-path should be defined as full path, like this: /soc/serial@7e201400:115200n8.

However, when I fix this, the device does not boot at all. This is verified by the ACT LED not blinking and ethernet port LEDs not blinking.

When I disable my overlay that updates /chosen by commenting it out in config.txt, the device boots normally.

Redirect U-Boot console to UART2 in RPi 4B

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