arch/ppc/boot/simple/uartlite_tty.c

   1 /*
   2  * Xilinx UARTLITE bootloader driver
   3  *
   4  * Copyright (c) 2007 Secret Lab Technologies Ltd.
   5  *
   6  * This program is free software; you can redistribute  it and/or modify it
   7  * under  the terms of  the GNU General  Public License as published by the
   8  * Free Software Foundation;  either version 2 of the  License, or (at your
   9  * option) any later version.
  10  */
  11
  12 #include <linux/types.h>
  13 #include <asm/serial.h>
  14 #include <asm/io.h>
  15 #include <platforms/4xx/xparameters/xparameters.h>
  16
  17 #define UARTLITE_BASEADDR ((void*)(XPAR_UARTLITE_0_BASEADDR))
  18
  19 unsigned long
  20 serial_init(int chan, void *ignored)
  21 {
  22         /* Clear the RX FIFO */
  23         out_be32(UARTLITE_BASEADDR + 0x0C, 0x2);
  24         return 0;
  25 }
  26
  27 void
  28 serial_putc(unsigned long com_port, unsigned char c)
  29 {
  30         while ((in_be32(UARTLITE_BASEADDR + 0x8) & 0x08) != 0); /* spin */
  31         out_be32(UARTLITE_BASEADDR + 0x4, c);
  32 }
  33
  34 unsigned char
  35 serial_getc(unsigned long com_port)
  36 {
  37         while ((in_be32(UARTLITE_BASEADDR + 0x8) & 0x01) == 0); /* spin */
  38         return in_be32(UARTLITE_BASEADDR);
  39 }
  40
  41 int
  42 serial_tstc(unsigned long com_port)
  43 {
  44         return ((in_be32(UARTLITE_BASEADDR + 0x8) & 0x01) != 0);
  45 }