sys/kern/subr_autoconf.c

   1 /*
   2  * Copyright (c) 1992, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * This software was developed by the Computer Systems Engineering group
   6  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
   7  * contributed to Berkeley.
   8  *
   9  * All advertising materials mentioning features or use of this software
  10  * must display the following acknowledgement:
  11  *      This product includes software developed by the University of
  12  *      California, Lawrence Berkeley Laboratories.
  13  *
  14  * Redistribution and use in source and binary forms, with or without
  15  * modification, are permitted provided that the following conditions
  16  * are met:
  17  * 1. Redistributions of source code must retain the above copyright
  18  *    notice, this list of conditions and the following disclaimer.
  19  * 2. Redistributions in binary form must reproduce the above copyright
  20  *    notice, this list of conditions and the following disclaimer in the
  21  *    documentation and/or other materials provided with the distribution.
  22  * 3. Neither the name of the University nor the names of its contributors
  23  *    may be used to endorse or promote products derived from this software
  24  *    without specific prior written permission.
  25  *
  26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  36  * SUCH DAMAGE.
  37  *
  38  *      @(#)subr_autoconf.c     8.1 (Berkeley) 6/10/93
  39  *
  40  * $FreeBSD: src/sys/kern/subr_autoconf.c,v 1.14 1999/10/05 21:19:41 n_hibma Exp $
  41  */
  42
  43 #include <sys/param.h>
  44 #include <sys/kernel.h>
  45 #include <sys/systm.h>
  46 #include <sys/thread.h>
  47
  48 /*
  49  * Autoconfiguration subroutines.
  50  */
  51
  52 /*
  53  * "Interrupt driven config" functions.
  54  */
  55 static TAILQ_HEAD(, intr_config_hook) intr_config_hook_list =
  56         TAILQ_HEAD_INITIALIZER(intr_config_hook_list);
  57
  58
  59 /* ARGSUSED */
  60 static void run_interrupt_driven_config_hooks (void *dummy);
  61 static int ran_config_hooks;
  62 static struct lock intr_config_lk = LOCK_INITIALIZER("intrcfg", 0, 0);
  63
  64 static void
  65 run_interrupt_driven_config_hooks(void *dummy)
  66 {
  67         struct intr_config_hook *hook_entry;
  68         int save_ticks = ticks;
  69         int save_count;
  70         int waiting;
  71
  72         lockmgr(&intr_config_lk, LK_EXCLUSIVE);
  73         save_count = ran_config_hooks++;
  74         while (!TAILQ_EMPTY(&intr_config_hook_list)) {
  75                 TAILQ_FOREACH(hook_entry, &intr_config_hook_list, ich_links) {
  76                         if (hook_entry->ich_ran == 0) {
  77                                 hook_entry->ich_ran = 1;
  78                                 lockmgr(&intr_config_lk, LK_RELEASE);
  79                                 (*hook_entry->ich_func)(hook_entry->ich_arg);
  80                                 lockmgr(&intr_config_lk, LK_EXCLUSIVE);
  81                                 break;
  82                         }
  83                 }
  84                 if (hook_entry)
  85                         continue;
  86                 if (TAILQ_EMPTY(&intr_config_hook_list))
  87                         break;
  88
  89                 waiting = (ticks - save_ticks + 1) / hz;
  90
  91                 if (waiting >= 10 && (waiting % 10) == 0) {
  92                         kprintf("**WARNING** waiting for the following device "
  93                                 "to finish configuring:\n");
  94                         TAILQ_FOREACH(hook_entry, &intr_config_hook_list,
  95                                       ich_links) {
  96                             kprintf("  %s:\tfunc=%p arg=%p\n",
  97                                 (hook_entry->ich_desc ?
  98                                     hook_entry->ich_desc : "?"),
  99                                 hook_entry->ich_func,
 100                                 hook_entry->ich_arg);
 101                         }
 102                         if (save_count || waiting >= 30) {
 103                                 kprintf("Giving up, interrupt routing is "
 104                                         "probably hosed\n");
 105                                 break;
 106                         }
 107                 }
 108                 lksleep(&intr_config_hook_list, &intr_config_lk,
 109                         0, "conifhk", hz);
 110                 ++waiting;
 111         }
 112         lockmgr(&intr_config_lk, LK_RELEASE);
 113
 114         /*
 115          * Terrible hack to give U4B (usb) a chance to configure, else
 116          * the root mount might not see a valid usb device.  This can happen
 117          * because the AHCI devices might have already finished probing
 118          * before the usb ports are even registered.
 119          */
 120 #ifndef _KERNEL_VIRTUAL
 121         if (save_count == 0) {
 122                 while (ticks - save_ticks < 5*hz)
 123                         tsleep(&intr_config_hook_list, 0, "delay", hz / 10);
 124         }
 125 #endif
 126
 127 }
 128 SYSINIT(intr_config_hooks, SI_SUB_INT_CONFIG_HOOKS, SI_ORDER_FIRST,
 129         run_interrupt_driven_config_hooks, NULL);
 130
 131 /*
 132  * Register a hook that will be called after "cold"
 133  * autoconfiguration is complete and interrupts can
 134  * be used to complete initialization.
 135  */
 136 int
 137 config_intrhook_establish(struct intr_config_hook *hook)
 138 {
 139         struct intr_config_hook *hook_entry;
 140
 141         lockmgr(&intr_config_lk, LK_EXCLUSIVE);
 142         for (hook_entry = TAILQ_FIRST(&intr_config_hook_list);
 143              hook_entry != NULL;
 144              hook_entry = TAILQ_NEXT(hook_entry, ich_links)) {
 145                 if (hook_entry == hook)
 146                         break;
 147                 if (hook_entry->ich_order > hook->ich_order)
 148                         break;
 149         }
 150         if (hook_entry == hook) {
 151                 kprintf("config_intrhook_establish: establishing an "
 152                        "already established hook.\n");
 153                 lockmgr(&intr_config_lk, LK_RELEASE);
 154                 return (1);
 155         }
 156         hook->ich_ran = 0;
 157
 158         /*
 159          * Insert
 160          */
 161         if (hook_entry)
 162                 TAILQ_INSERT_BEFORE(hook_entry, hook, ich_links);
 163         else
 164                 TAILQ_INSERT_TAIL(&intr_config_hook_list, hook, ich_links);
 165
 166         /*
 167          * Late hook, run immediately.
 168          */
 169         if (ran_config_hooks) {
 170                 lockmgr(&intr_config_lk, LK_RELEASE);
 171                 run_interrupt_driven_config_hooks(NULL);
 172                 lockmgr(&intr_config_lk, LK_EXCLUSIVE);
 173         }
 174         lockmgr(&intr_config_lk, LK_RELEASE);
 175
 176         return (0);
 177 }
 178
 179 void
 180 config_intrhook_disestablish(struct intr_config_hook *hook)
 181 {
 182         struct intr_config_hook *hook_entry;
 183
 184         lockmgr(&intr_config_lk, LK_EXCLUSIVE);
 185         for (hook_entry = TAILQ_FIRST(&intr_config_hook_list);
 186              hook_entry != NULL;
 187              hook_entry = TAILQ_NEXT(hook_entry, ich_links)) {
 188                 if (hook_entry == hook)
 189                         break;
 190         }
 191         if (hook_entry == NULL) {
 192                 lockmgr(&intr_config_lk, LK_RELEASE);
 193                 panic("config_intrhook_disestablish: disestablishing an "
 194                       "unestablished hook (%p)", hook);
 195         }
 196
 197         TAILQ_REMOVE(&intr_config_hook_list, hook, ich_links);
 198         /* Wakeup anyone watching the list */
 199         wakeup(&intr_config_hook_list);
 200         lockmgr(&intr_config_lk, LK_RELEASE);
 201 }