How to set dual UART on Telink Mesh TLSR8258 SDK ?

* Current uart_init() function is below.

How to add additional UART ?

void user_uart_init(void)

{ 

    uart_recbuff_init((unsigned short *)(&T_rxdata_buf), sizeof(T_rxdata_buf), (u8 *)(&T_txdata_buf));

    uart_gpio_set(GPIO_PD3, GPIO_PD7);

    uart_reset(); 

    #if (CLOCK_SYS_CLOCK_HZ == 16000000)

    uart_init(9, 13, PARITY_NONE, STOP_BIT_ONE);

    #elif (CLOCK_SYS_CLOCK_HZ == 24000000)

    uart_init(12, 15, PARITY_NONE, STOP_BIT_ONE);

    #endif

    uart_dma_enable(1, 1);

    irq_set_mask(FLD_IRQ_DMA_EN);

    dma_chn_irq_enable(FLD_DMA_CHN_UART_RX | FLD_DMA_CHN_UART_TX, 1);

   reg_dma_rx_rdy0 = FLD_DMA_CHN_UART_RX | FLD_DMA_CHN_UART_TX;

}