xref: /netbsd-src/sys/arch/cobalt/stand/boot/ns16550.c (revision a93ea220fcb3e34cdfdcd4d7a5d391e0b2b4f2ba)
1 /*	$NetBSD: ns16550.c,v 1.1 2003/06/25 17:24:22 cdi 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 int calculated_speed;
43 
44 volatile struct NS16550 *
45 NS16550_init(addr, speed)
46 	int addr;
47 	int speed;
48 {
49 	struct NS16550 *com_port;
50 
51 	com_port = (struct NS16550 *)(COMBASE + addr);
52 
53 	com_port->lcr = 0x80;  /* Access baud rate */
54 	speed = comspeed(speed);
55 	com_port->dll = speed;
56 	com_port->dlm = speed >> 8;
57 
58 	com_port->lcr = 0x03;  /* 8 data, 1 stop, no parity */
59 	com_port->mcr = 0x03;  /* 8 bits */
60 	com_port->fcr = 0x07;  /* Clear & enable FIFOs */
61 	com_port->ier = 0x00;
62 
63 	return (com_port);
64 }
65 
66 void
67 NS16550_putc(com_port, c)
68 	volatile struct NS16550 *com_port;
69 	int c;
70 {
71 
72 	while ((com_port->lsr & LSR_THRE) == 0)
73 		;
74 	com_port->thr = c;
75 }
76 
77 int
78 NS16550_getc(com_port)
79 	volatile struct NS16550 *com_port;
80 {
81 
82 	while ((com_port->lsr & LSR_DR) == 0)
83 		;
84 	return (com_port->rbr);
85 }
86 
87 int
88 NS16550_scankbd(com_port)
89 	volatile struct NS16550 *com_port;
90 {
91 
92 	if ((com_port->lsr & LSR_DR) == 0)
93 		return -1;
94 	return (com_port->rbr);
95 }
96 
97 int
98 NS16550_test(com_port)
99 	volatile struct NS16550 *com_port;
100 {
101 
102 	return ((com_port->lsr & LSR_DR) != 0)
103 		;
104 }
105 #endif /* CONS_SERIAL */
106