xref: /freebsd-12.1/sys/dev/bvm/bvm_console.c (revision bb487d2b)
1 /*-
2  * Copyright (c) 2011 NetApp, Inc.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL NETAPP, INC OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  *
26  * $FreeBSD$
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <sys/param.h>
33 #include <sys/kernel.h>
34 #include <sys/systm.h>
35 #include <sys/types.h>
36 #include <sys/cons.h>
37 #include <sys/tty.h>
38 #include <sys/reboot.h>
39 #include <sys/bus.h>
40 
41 #include <sys/kdb.h>
42 #include <ddb/ddb.h>
43 
44 #ifndef	BVMCONS_POLL_HZ
45 #define	BVMCONS_POLL_HZ	4
46 #endif
47 #define BVMBURSTLEN	16	/* max number of bytes to write in one chunk */
48 
49 static tsw_open_t bvm_tty_open;
50 static tsw_close_t bvm_tty_close;
51 static tsw_outwakeup_t bvm_tty_outwakeup;
52 
53 static struct ttydevsw bvm_ttydevsw = {
54 	.tsw_flags	= TF_NOPREFIX,
55 	.tsw_open	= bvm_tty_open,
56 	.tsw_close	= bvm_tty_close,
57 	.tsw_outwakeup	= bvm_tty_outwakeup,
58 };
59 
60 static int			polltime;
61 static struct callout		bvm_timer;
62 
63 #if defined(KDB)
64 static int			alt_break_state;
65 #endif
66 
67 #define	BVM_CONS_PORT	0x220
68 static int bvm_cons_port = BVM_CONS_PORT;
69 
70 #define BVM_CONS_SIG	('b' << 8 | 'v')
71 
72 static void	bvm_timeout(void *);
73 
74 static cn_probe_t	bvm_cnprobe;
75 static cn_init_t	bvm_cninit;
76 static cn_term_t	bvm_cnterm;
77 static cn_getc_t	bvm_cngetc;
78 static cn_putc_t	bvm_cnputc;
79 static cn_grab_t 	bvm_cngrab;
80 static cn_ungrab_t 	bvm_cnungrab;
81 
82 CONSOLE_DRIVER(bvm);
83 
84 static int
85 bvm_rcons(u_char *ch)
86 {
87 	int c;
88 
89 	c = inl(bvm_cons_port);
90 	if (c != -1) {
91 		*ch = (u_char)c;
92 		return (0);
93 	} else
94 		return (-1);
95 }
96 
97 static void
98 bvm_wcons(u_char ch)
99 {
100 
101 	outl(bvm_cons_port, ch);
102 }
103 
104 static void
105 cn_drvinit(void *unused)
106 {
107 	struct tty *tp;
108 
109 	if (bvm_consdev.cn_pri != CN_DEAD) {
110 		tp = tty_alloc(&bvm_ttydevsw, NULL);
111 		callout_init_mtx(&bvm_timer, tty_getlock(tp), 0);
112 		tty_makedev(tp, NULL, "bvmcons");
113 	}
114 }
115 
116 static int
117 bvm_tty_open(struct tty *tp)
118 {
119 	polltime = hz / BVMCONS_POLL_HZ;
120 	if (polltime < 1)
121 		polltime = 1;
122 	callout_reset(&bvm_timer, polltime, bvm_timeout, tp);
123 
124 	return (0);
125 }
126 
127 static void
128 bvm_tty_close(struct tty *tp)
129 {
130 
131 	tty_lock_assert(tp, MA_OWNED);
132 	callout_stop(&bvm_timer);
133 }
134 
135 static void
136 bvm_tty_outwakeup(struct tty *tp)
137 {
138 	int len, written;
139 	u_char buf[BVMBURSTLEN];
140 
141 	for (;;) {
142 		len = ttydisc_getc(tp, buf, sizeof(buf));
143 		if (len == 0)
144 			break;
145 
146 		written = 0;
147 		while (written < len)
148 			bvm_wcons(buf[written++]);
149 	}
150 }
151 
152 static void
153 bvm_timeout(void *v)
154 {
155 	struct	tty *tp;
156 	int 	c;
157 
158 	tp = (struct tty *)v;
159 
160 	tty_lock_assert(tp, MA_OWNED);
161 	while ((c = bvm_cngetc(NULL)) != -1)
162 		ttydisc_rint(tp, c, 0);
163 	ttydisc_rint_done(tp);
164 
165 	callout_reset(&bvm_timer, polltime, bvm_timeout, tp);
166 }
167 
168 static void
169 bvm_cnprobe(struct consdev *cp)
170 {
171 	int disabled, port;
172 
173 	disabled = 0;
174 	cp->cn_pri = CN_DEAD;
175 	strcpy(cp->cn_name, "bvmcons");
176 
177 	resource_int_value("bvmconsole", 0, "disabled", &disabled);
178 	if (!disabled) {
179 		if (resource_int_value("bvmconsole", 0, "port", &port) == 0)
180 			bvm_cons_port = port;
181 
182 		if (inw(bvm_cons_port) == BVM_CONS_SIG)
183 			cp->cn_pri = CN_REMOTE;
184 	}
185 }
186 
187 static void
188 bvm_cninit(struct consdev *cp)
189 {
190 	int i;
191 	const char *bootmsg = "Using bvm console.\n";
192 
193 	if (boothowto & RB_VERBOSE) {
194 		for (i = 0; i < strlen(bootmsg); i++)
195 			bvm_cnputc(cp, bootmsg[i]);
196 	}
197 }
198 
199 static void
200 bvm_cnterm(struct consdev *cp)
201 {
202 
203 }
204 
205 static int
206 bvm_cngetc(struct consdev *cp)
207 {
208 	unsigned char ch;
209 
210 	if (bvm_rcons(&ch) == 0) {
211 #if defined(KDB)
212 		kdb_alt_break(ch, &alt_break_state);
213 #endif
214 		return (ch);
215 	}
216 
217 	return (-1);
218 }
219 
220 static void
221 bvm_cnputc(struct consdev *cp, int c)
222 {
223 
224 	bvm_wcons(c);
225 }
226 
227 static void
228 bvm_cngrab(struct consdev *cp)
229 {
230 }
231 
232 static void
233 bvm_cnungrab(struct consdev *cp)
234 {
235 }
236 
237 SYSINIT(cndev, SI_SUB_CONFIGURE, SI_ORDER_MIDDLE, cn_drvinit, NULL);
238