xref: /freebsd/stand/libofw/ofw_console.c (revision 62a52c15422470f97fc7b311d89c83f910bcc1b1)
1 /* $NetBSD: prom.c,v 1.3 1997/09/06 14:03:58 drochner Exp $ */
2 
3 /*-
4  * Mach Operating System
5  * Copyright (c) 1992 Carnegie Mellon University
6  * All Rights Reserved.
7  *
8  * Permission to use, copy, modify and distribute this software and its
9  * documentation is hereby granted, provided that both the copyright
10  * notice and this permission notice appear in all copies of the
11  * software, derivative works or modified versions, and any portions
12  * thereof, and that both notices appear in supporting documentation.
13  *
14  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
15  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
16  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
17  *
18  * Carnegie Mellon requests users of this software to return to
19  *
20  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
21  *  School of Computer Science
22  *  Carnegie Mellon University
23  *  Pittsburgh PA 15213-3890
24  *
25  * any improvements or extensions that they make and grant Carnegie Mellon
26  * the rights to redistribute these changes.
27  */
28 
29 #include <sys/types.h>
30 
31 #include "bootstrap.h"
32 #include "openfirm.h"
33 
34 static void ofw_cons_probe(struct console *cp);
35 static int ofw_cons_init(int);
36 void ofw_cons_putchar(int);
37 int ofw_cons_getchar(void);
38 int ofw_cons_poll(void);
39 
40 static ihandle_t stdin;
41 static ihandle_t stdout;
42 
43 struct console ofwconsole = {
44 	"ofw",
45 	"Open Firmware console",
46 	0,
47 	ofw_cons_probe,
48 	ofw_cons_init,
49 	ofw_cons_putchar,
50 	ofw_cons_getchar,
51 	ofw_cons_poll,
52 };
53 
54 static void
55 ofw_cons_probe(struct console *cp)
56 {
57 
58 	OF_getprop(chosen, "stdin", &stdin, sizeof(stdin));
59 	OF_getprop(chosen, "stdout", &stdout, sizeof(stdout));
60 	cp->c_flags |= C_PRESENTIN|C_PRESENTOUT;
61 }
62 
63 static int
64 ofw_cons_init(int arg)
65 {
66 	return 0;
67 }
68 
69 void
70 ofw_cons_putchar(int c)
71 {
72 	char cbuf;
73 
74 	if (c == '\n') {
75 		cbuf = '\r';
76 		OF_write(stdout, &cbuf, 1);
77 	}
78 
79 	cbuf = c;
80 	OF_write(stdout, &cbuf, 1);
81 }
82 
83 static int saved_char = -1;
84 
85 int
86 ofw_cons_getchar(void)
87 {
88 	unsigned char ch = '\0';
89 	int l;
90 
91 	if (saved_char != -1) {
92 		l = saved_char;
93 		saved_char = -1;
94 		return l;
95 	}
96 
97 	/* At least since version 4.0.0, QEMU became bug-compatible
98 	 * with PowerVM's vty, by inserting a \0 after every \r.
99 	 * As this confuses loader's interpreter and as a \0 coming
100 	 * from the console doesn't seem reasonable, it's filtered here. */
101 	if (OF_read(stdin, &ch, 1) > 0 && ch != '\0')
102 		return (ch);
103 
104 	return (-1);
105 }
106 
107 int
108 ofw_cons_poll(void)
109 {
110 	unsigned char ch;
111 
112 	if (saved_char != -1)
113 		return 1;
114 
115 	if (OF_read(stdin, &ch, 1) > 0) {
116 		saved_char = ch;
117 		return 1;
118 	}
119 
120 	return 0;
121 }
122