tag	line	file	source code
UART_TX	257	kernel/chr_drv/serial.c	serial_outp(info, UART_TX, info->x_char);
UART_TX	262	kernel/chr_drv/serial.c	serial_outp(info, UART_TX, queue->buf[tail++]);
UART_TX	694	kernel/chr_drv/serial.c	serial_outp(info, UART_TX, info->x_char);
UART_TX	704	kernel/chr_drv/serial.c	serial_outp(info, UART_TX, queue->buf[tail++]);