xref: /netbsd-src/sys/arch/prep/stand/boot/ns16550.c (revision 4b896b232495b7a9b8b94a1cf1e21873296d53b8)
1 /*	$NetBSD: ns16550.c,v 1.1 2000/02/29 15:21:50 nonaka 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(addr, speed)
44 	int addr;
45 	int speed;
46 {
47 	struct NS16550 *com_port;
48 
49 	com_port = (struct NS16550 *)(COMBASE + addr);
50 
51 	com_port->lcr = 0x80;  /* Access baud rate */
52 	speed = comspeed(speed);
53 	com_port->dll = speed;
54 	com_port->dlm = speed >> 8;
55 
56 	com_port->lcr = 0x03;  /* 8 data, 1 stop, no parity */
57 	com_port->mcr = 0x00;
58 	com_port->fcr = 0x07;  /* Clear & enable FIFOs */
59 	com_port->ier = 0x00;
60 
61 	return (com_port);
62 }
63 
64 void
65 NS16550_putc(com_port, c)
66 	volatile struct NS16550 *com_port;
67 	int c;
68 {
69 
70 	while ((com_port->lsr & LSR_THRE) == 0)
71 		;
72 	com_port->thr = c;
73 }
74 
75 int
76 NS16550_getc(com_port)
77 	volatile struct NS16550 *com_port;
78 {
79 
80 	while ((com_port->lsr & LSR_DR) == 0)
81 		;
82 	return (com_port->rbr);
83 }
84 
85 int
86 NS16550_scankbd(com_port)
87 	volatile struct NS16550 *com_port;
88 {
89 
90 	if ((com_port->lsr & LSR_DR) == 0)
91 		return -1;
92 	return (com_port->rbr);
93 }
94 
95 int
96 NS16550_test(com_port)
97 	volatile struct NS16550 *com_port;
98 {
99 
100 	return ((com_port->lsr & LSR_DR) != 0)
101 		;
102 }
103 #endif /* CONS_SERIAL */
104