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  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 4. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  *
  33  *      @(#)subr_autoconf.c     8.1 (Berkeley) 6/10/93
  34  *
  35  */
  36
  37 #include <sys/cdefs.h>
  38 __FBSDID("$FreeBSD$");
  39
  40 #include <sys/param.h>
  41 #include <sys/kernel.h>
  42 #include <sys/lock.h>
  43 #include <sys/mutex.h>
  44 #include <sys/systm.h>
  45
  46 /*
  47  * Autoconfiguration subroutines.
  48  */
  49
  50 /*
  51  * "Interrupt driven config" functions.
  52  */
  53 static TAILQ_HEAD(, intr_config_hook) intr_config_hook_list =
  54         TAILQ_HEAD_INITIALIZER(intr_config_hook_list);
  55 static struct mtx intr_config_hook_lock;
  56 MTX_SYSINIT(intr_config_hook, &intr_config_hook_lock, "intr config", MTX_DEF);
  57
  58 /* ARGSUSED */
  59 static void run_interrupt_driven_config_hooks(void *dummy);
  60
  61 static void
  62 run_interrupt_driven_config_hooks(dummy)
  63         void *dummy;
  64 {
  65         struct intr_config_hook *hook_entry, *next_entry;
  66
  67         mtx_lock(&intr_config_hook_lock);
  68         TAILQ_FOREACH_SAFE(hook_entry, &intr_config_hook_list, ich_links,
  69             next_entry) {
  70                 mtx_unlock(&intr_config_hook_lock);
  71                 (*hook_entry->ich_func)(hook_entry->ich_arg);
  72                 mtx_lock(&intr_config_hook_lock);
  73         }
  74
  75         while (!TAILQ_EMPTY(&intr_config_hook_list)) {
  76                 msleep(&intr_config_hook_list, &intr_config_hook_lock, PCONFIG,
  77                     "conifhk", 0);
  78         }
  79         mtx_unlock(&intr_config_hook_lock);
  80 }
  81 SYSINIT(intr_config_hooks, SI_SUB_INT_CONFIG_HOOKS, SI_ORDER_FIRST,
  82         run_interrupt_driven_config_hooks, NULL);
  83
  84 /*
  85  * Register a hook that will be called after "cold"
  86  * autoconfiguration is complete and interrupts can
  87  * be used to complete initialization.
  88  */
  89 int
  90 config_intrhook_establish(hook)
  91         struct intr_config_hook *hook;
  92 {
  93         struct intr_config_hook *hook_entry;
  94
  95         mtx_lock(&intr_config_hook_lock);
  96         TAILQ_FOREACH(hook_entry, &intr_config_hook_list, ich_links)
  97                 if (hook_entry == hook)
  98                         break;
  99         if (hook_entry != NULL) {
 100                 mtx_unlock(&intr_config_hook_lock);
 101                 printf("config_intrhook_establish: establishing an "
 102                        "already established hook.\n");
 103                 return (1);
 104         }
 105         TAILQ_INSERT_TAIL(&intr_config_hook_list, hook, ich_links);
 106         mtx_unlock(&intr_config_hook_lock);
 107         if (cold == 0)
 108                 /* XXX Sufficient for modules loaded after initial config??? */
 109                 run_interrupt_driven_config_hooks(NULL);
 110         return (0);
 111 }
 112
 113 void
 114 config_intrhook_disestablish(hook)
 115         struct intr_config_hook *hook;
 116 {
 117         struct intr_config_hook *hook_entry;
 118
 119         mtx_lock(&intr_config_hook_lock);
 120         TAILQ_FOREACH(hook_entry, &intr_config_hook_list, ich_links)
 121                 if (hook_entry == hook)
 122                         break;
 123         if (hook_entry == NULL)
 124                 panic("config_intrhook_disestablish: disestablishing an "
 125                       "unestablished hook");
 126
 127         TAILQ_REMOVE(&intr_config_hook_list, hook, ich_links);
 128
 129         /* Wakeup anyone watching the list */
 130         wakeup(&intr_config_hook_list);
 131         mtx_unlock(&intr_config_hook_lock);
 132 }