sys/dev/bvm/bvm_console.c

   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
  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
 100 bvm_wcons(u_char ch)
 101 {
 102
 103         outl(bvm_cons_port, ch);
 104 }
 105
 106 static void
 107 cn_drvinit(void *unused)
 108 {
 109         struct tty *tp;
 110
 111         gone_in(13, "bvmconsole");
 112
 113         if (bvm_consdev.cn_pri != CN_DEAD) {
 114                 tp = tty_alloc(&bvm_ttydevsw, NULL);
 115                 callout_init_mtx(&bvm_timer, tty_getlock(tp), 0);
 116                 tty_makedev(tp, NULL, "bvmcons");
 117         }
 118 }
 119
 120 static int
 121 bvm_tty_open(struct tty *tp)
 122 {
 123         polltime = hz / BVMCONS_POLL_HZ;
 124         if (polltime < 1)
 125                 polltime = 1;
 126         callout_reset(&bvm_timer, polltime, bvm_timeout, tp);
 127
 128         return (0);
 129 }
 130
 131 static void
 132 bvm_tty_close(struct tty *tp)
 133 {
 134
 135         tty_assert_locked(tp);
 136         callout_stop(&bvm_timer);
 137 }
 138
 139 static void
 140 bvm_tty_outwakeup(struct tty *tp)
 141 {
 142         int len, written;
 143         u_char buf[BVMBURSTLEN];
 144
 145         for (;;) {
 146                 len = ttydisc_getc(tp, buf, sizeof(buf));
 147                 if (len == 0)
 148                         break;
 149
 150                 written = 0;
 151                 while (written < len)
 152                         bvm_wcons(buf[written++]);
 153         }
 154 }
 155
 156 static void
 157 bvm_timeout(void *v)
 158 {
 159         struct  tty *tp;
 160         int     c;
 161
 162         tp = (struct tty *)v;
 163
 164         tty_assert_locked(tp);
 165         while ((c = bvm_cngetc(NULL)) != -1)
 166                 ttydisc_rint(tp, c, 0);
 167         ttydisc_rint_done(tp);
 168
 169         callout_reset(&bvm_timer, polltime, bvm_timeout, tp);
 170 }
 171
 172 static void
 173 bvm_cnprobe(struct consdev *cp)
 174 {
 175         int disabled, port;
 176
 177         disabled = 0;
 178         cp->cn_pri = CN_DEAD;
 179         strcpy(cp->cn_name, "bvmcons");
 180
 181         resource_int_value("bvmconsole", 0, "disabled", &disabled);
 182         if (!disabled) {
 183                 if (resource_int_value("bvmconsole", 0, "port", &port) == 0)
 184                         bvm_cons_port = port;
 185
 186                 if (inw(bvm_cons_port) == BVM_CONS_SIG)
 187                         cp->cn_pri = CN_REMOTE;
 188         }
 189 }
 190
 191 static void
 192 bvm_cninit(struct consdev *cp)
 193 {
 194         int i;
 195         const char *bootmsg = "Using bvm console.\n";
 196
 197         if (boothowto & RB_VERBOSE) {
 198                 for (i = 0; i < strlen(bootmsg); i++)
 199                         bvm_cnputc(cp, bootmsg[i]);
 200         }
 201 }
 202
 203 static void
 204 bvm_cnterm(struct consdev *cp)
 205 {
 206
 207 }
 208
 209 static int
 210 bvm_cngetc(struct consdev *cp)
 211 {
 212         unsigned char ch;
 213
 214         if (bvm_rcons(&ch) == 0) {
 215 #if defined(KDB)
 216                 kdb_alt_break(ch, &alt_break_state);
 217 #endif
 218                 return (ch);
 219         }
 220
 221         return (-1);
 222 }
 223
 224 static void
 225 bvm_cnputc(struct consdev *cp, int c)
 226 {
 227
 228         bvm_wcons(c);
 229 }
 230
 231 static void
 232 bvm_cngrab(struct consdev *cp)
 233 {
 234 }
 235
 236 static void
 237 bvm_cnungrab(struct consdev *cp)
 238 {
 239 }
 240
 241 SYSINIT(cndev, SI_SUB_CONFIGURE, SI_ORDER_MIDDLE, cn_drvinit, NULL);