Console on AR933X serial port

configname: CONFIG_SERIAL_AR933X_CONSOLE

Linux Kernel Configuration
└─>Device Drivers
└─>Character devices
└─>Serial drivers
└─>Console on AR933X serial port
In linux kernel since version 3.1 (release Date: 2011-10-24)  
Enable a built-in UART port of the AR933X to be the system console.