You can change the serial output port of the Bootloader. The standard port is the FFUART, which is the lower RS232 connector on our Colibri Evaluation Board.
To change the port to the BT UART (higher RS232 connector on the evaluation board) type in the bootloader menu:
x set set ser.port = 0x40200000 save ser
Select one of the ports by assigning 1, 2 or 3 to ser.port . 1=UART A 2=UART B 3=UART C as defined in the SO-DIMM/MXM3 pinout.
x set set ser.port = 2 save ser
It is not possible to use an other pin mux setting than the default one in the bootloader.