rt-thread/bsp/allwinner_tina/drivers/Kconfig

config TINA_USING_UART0
    bool "Using UART0"
    select RT_USING_SERIAL
    default n

config TINA_USING_UART1
    bool "Using UART1"
    select RT_USING_SERIAL
    default y

config TINA_USING_UART2
    bool "Using UART2"
    select RT_USING_SERIAL
    default y