Serial debug port?

I’m trying to debug linux booting issues, and I’m seeing that the default image has a console=ttyS2,1500000 parameter in /proc/cmdline, indicating that it has a serial console somewhere.

Does the uConsole have a serial port that I can access to get a uboot boot prompt and/or early linux kernel logs?

I’m using the rockchip-a06, by the way.

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Same looking the serial port on uConsole…
Looks like it’s GPIO32/GPIO33 on expansion port, but I’m using 4G module, and GPIO33 is used by it.

Need to find the difference from devterm and uconsole about pinmux and serial…
maybe some can give a hint?

Edit:
I’m checking device tree when I found that serial2 (serial@ff1a0000) seems not enabled at all.
Where are the changes/patches about 4G module support? @guu

The UART port on the 4G module is intended for use with the 4G module itself only.

I mean this one, not that “debug UART” on 4G module:

Unfortunately, there isn’t enough space to have an external breakout, so you’ll have to do the wires yourself, or use a DT expansion board. The DT has the UART.