xref: /freebsd-12.1/sys/dev/bvm/bvm_console.c (revision 718cf2cc)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2011 NetApp, Inc.
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  *
16  * THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL NETAPP, INC OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * $FreeBSD$
29  */
30 
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33 
34 #include <sys/param.h>
35 #include <sys/kernel.h>
36 #include <sys/systm.h>
37 #include <sys/types.h>
38 #include <sys/cons.h>
39 #include <sys/tty.h>
40 #include <sys/reboot.h>
41 #include <sys/bus.h>
42 
43 #include <sys/kdb.h>
44 #include <ddb/ddb.h>
45 
46 #ifndef	BVMCONS_POLL_HZ
47 #define	BVMCONS_POLL_HZ	4
48 #endif
49 #define BVMBURSTLEN	16	/* max number of bytes to write in one chunk */
50 
51 static tsw_open_t bvm_tty_open;
52 static tsw_close_t bvm_tty_close;
53 static tsw_outwakeup_t bvm_tty_outwakeup;
54 
55 static struct ttydevsw bvm_ttydevsw = {
56 	.tsw_flags	= TF_NOPREFIX,
57 	.tsw_open	= bvm_tty_open,
58 	.tsw_close	= bvm_tty_close,
59 	.tsw_outwakeup	= bvm_tty_outwakeup,
60 };
61 
62 static int			polltime;
63 static struct callout		bvm_timer;
64 
65 #if defined(KDB)
66 static int			alt_break_state;
67 #endif
68 
69 #define	BVM_CONS_PORT	0x220
70 static int bvm_cons_port = BVM_CONS_PORT;
71 
72 #define BVM_CONS_SIG	('b' << 8 | 'v')
73 
74 static void	bvm_timeout(void *);
75 
76 static cn_probe_t	bvm_cnprobe;
77 static cn_init_t	bvm_cninit;
78 static cn_term_t	bvm_cnterm;
79 static cn_getc_t	bvm_cngetc;
80 static cn_putc_t	bvm_cnputc;
81 static cn_grab_t 	bvm_cngrab;
82 static cn_ungrab_t 	bvm_cnungrab;
83 
84 CONSOLE_DRIVER(bvm);
85 
86 static int
bvm_rcons(u_char * ch)87 bvm_rcons(u_char *ch)
88 {
89 	int c;
90 
91 	c = inl(bvm_cons_port);
92 	if (c != -1) {
93 		*ch = (u_char)c;
94 		return (0);
95 	} else
96 		return (-1);
97 }
98 
99 static void
bvm_wcons(u_char ch)100 bvm_wcons(u_char ch)
101 {
102 
103 	outl(bvm_cons_port, ch);
104 }
105 
106 static void
cn_drvinit(void * unused)107 cn_drvinit(void *unused)
108 {
109 	struct tty *tp;
110 
111 	if (bvm_consdev.cn_pri != CN_DEAD) {
112 		tp = tty_alloc(&bvm_ttydevsw, NULL);
113 		callout_init_mtx(&bvm_timer, tty_getlock(tp), 0);
114 		tty_makedev(tp, NULL, "bvmcons");
115 	}
116 }
117 
118 static int
bvm_tty_open(struct tty * tp)119 bvm_tty_open(struct tty *tp)
120 {
121 	polltime = hz / BVMCONS_POLL_HZ;
122 	if (polltime < 1)
123 		polltime = 1;
124 	callout_reset(&bvm_timer, polltime, bvm_timeout, tp);
125 
126 	return (0);
127 }
128 
129 static void
bvm_tty_close(struct tty * tp)130 bvm_tty_close(struct tty *tp)
131 {
132 
133 	tty_lock_assert(tp, MA_OWNED);
134 	callout_stop(&bvm_timer);
135 }
136 
137 static void
bvm_tty_outwakeup(struct tty * tp)138 bvm_tty_outwakeup(struct tty *tp)
139 {
140 	int len, written;
141 	u_char buf[BVMBURSTLEN];
142 
143 	for (;;) {
144 		len = ttydisc_getc(tp, buf, sizeof(buf));
145 		if (len == 0)
146 			break;
147 
148 		written = 0;
149 		while (written < len)
150 			bvm_wcons(buf[written++]);
151 	}
152 }
153 
154 static void
bvm_timeout(void * v)155 bvm_timeout(void *v)
156 {
157 	struct	tty *tp;
158 	int 	c;
159 
160 	tp = (struct tty *)v;
161 
162 	tty_lock_assert(tp, MA_OWNED);
163 	while ((c = bvm_cngetc(NULL)) != -1)
164 		ttydisc_rint(tp, c, 0);
165 	ttydisc_rint_done(tp);
166 
167 	callout_reset(&bvm_timer, polltime, bvm_timeout, tp);
168 }
169 
170 static void
bvm_cnprobe(struct consdev * cp)171 bvm_cnprobe(struct consdev *cp)
172 {
173 	int disabled, port;
174 
175 	disabled = 0;
176 	cp->cn_pri = CN_DEAD;
177 	strcpy(cp->cn_name, "bvmcons");
178 
179 	resource_int_value("bvmconsole", 0, "disabled", &disabled);
180 	if (!disabled) {
181 		if (resource_int_value("bvmconsole", 0, "port", &port) == 0)
182 			bvm_cons_port = port;
183 
184 		if (inw(bvm_cons_port) == BVM_CONS_SIG)
185 			cp->cn_pri = CN_REMOTE;
186 	}
187 }
188 
189 static void
bvm_cninit(struct consdev * cp)190 bvm_cninit(struct consdev *cp)
191 {
192 	int i;
193 	const char *bootmsg = "Using bvm console.\n";
194 
195 	if (boothowto & RB_VERBOSE) {
196 		for (i = 0; i < strlen(bootmsg); i++)
197 			bvm_cnputc(cp, bootmsg[i]);
198 	}
199 }
200 
201 static void
bvm_cnterm(struct consdev * cp)202 bvm_cnterm(struct consdev *cp)
203 {
204 
205 }
206 
207 static int
bvm_cngetc(struct consdev * cp)208 bvm_cngetc(struct consdev *cp)
209 {
210 	unsigned char ch;
211 
212 	if (bvm_rcons(&ch) == 0) {
213 #if defined(KDB)
214 		kdb_alt_break(ch, &alt_break_state);
215 #endif
216 		return (ch);
217 	}
218 
219 	return (-1);
220 }
221 
222 static void
bvm_cnputc(struct consdev * cp,int c)223 bvm_cnputc(struct consdev *cp, int c)
224 {
225 
226 	bvm_wcons(c);
227 }
228 
229 static void
bvm_cngrab(struct consdev * cp)230 bvm_cngrab(struct consdev *cp)
231 {
232 }
233 
234 static void
bvm_cnungrab(struct consdev * cp)235 bvm_cnungrab(struct consdev *cp)
236 {
237 }
238 
239 SYSINIT(cndev, SI_SUB_CONFIGURE, SI_ORDER_MIDDLE, cn_drvinit, NULL);
240