Console on DC21285 serial port

configname: CONFIG_SERIAL_21285_CONSOLE

Linux Kernel Configuration
└─>Device Drivers
└─>Character devices
└─>Serial drivers
└─>Console on DC21285 serial port
In linux kernel since version 2.6.20 (release Date: 2007-02-04)  
If you have enabled the serial port on the 21285 footbridge you can
make it the console by answering Y to this option.

Even if you say Y here, the currently visible virtual console
(/dev/tty0) will still be used as the system console by default, but
you can alter that using a kernel command line option such as
"console=ttyFB". (Try "man bootparam" or see the documentation of
your boot loader (lilo or loadlin) about how to pass options to the
kernel at boot time.)