sys/arch/prep/stand/boot/ns16550.c

   1 /*      $NetBSD: ns16550.c,v 1.2.26.1 2007/05/22 17:27:23 matt Exp $    */
   2
   3 /*-
   4  * Copyright (C) 1995-1997 Gary Thomas (gdt@linuxppc.org)
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  * 3. All advertising materials mentioning features or use of this software
  16  *    must display the following acknowledgement:
  17  *      This product includes software developed by Gary Thomas.
  18  * 4. The name of the author may not be used to endorse or promote products
  19  *    derived from this software without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  22  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  23  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  24  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  25  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  26  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  27  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  28  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  29  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  30  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  31  */
  32
  33 #ifdef CONS_SERIAL
  34 /*
  35  * NS16550 support
  36  */
  37
  38 #include <lib/libsa/stand.h>
  39 #include "boot.h"
  40 #include "ns16550.h"
  41
  42 volatile struct NS16550 *
  43 NS16550_init(int addr, int speed)
  44 {
  45         struct NS16550 *com_port;
  46
  47         com_port = (struct NS16550 *)(COMBASE + addr);
  48
  49         com_port->lcr = 0x80;  /* Access baud rate */
  50         speed = comspeed(speed);
  51         com_port->dll = speed;
  52         com_port->dlm = speed >> 8;
  53
  54         com_port->lcr = 0x03;  /* 8 data, 1 stop, no parity */
  55         com_port->mcr = 0x03;  /* Set DTR and RTS */
  56         com_port->fcr = 0x07;  /* Clear & enable FIFOs */
  57         com_port->ier = 0x00;
  58
  59         return (com_port);
  60 }
  61
  62 void
  63 NS16550_putc(volatile struct NS16550 *com_port, int c)
  64 {
  65
  66         while ((com_port->lsr & LSR_THRE) == 0)
  67                 ;
  68         com_port->thr = c;
  69 }
  70
  71 int
  72 NS16550_getc(volatile struct NS16550 *com_port)
  73 {
  74
  75         while ((com_port->lsr & LSR_DR) == 0)
  76                 ;
  77         return (com_port->rbr);
  78 }
  79
  80 int
  81 NS16550_scankbd(volatile struct NS16550 *com_port)
  82 {
  83
  84         if ((com_port->lsr & LSR_DR) == 0)
  85                 return -1;
  86         return (com_port->rbr);
  87 }
  88
  89 int
  90 NS16550_test(volatile struct NS16550 *com_port)
  91 {
  92
  93         return ((com_port->lsr & LSR_DR) != 0);
  94 }
  95 #endif /* CONS_SERIAL */