Initial import from FreeBSD RELENG_4:
[dragonfly.git] / 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. All advertising materials mentioning features or use of this software
23  *    must display the following acknowledgement:
24  *      This product includes software developed by the University of
25  *      California, Berkeley and its contributors.
26  * 4. Neither the name of the University nor the names of its contributors
27  *    may be used to endorse or promote products derived from this software
28  *    without specific prior written permission.
29  *
30  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
31  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
32  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
33  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
34  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
35  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
36  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
37  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
38  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
39  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
40  * SUCH DAMAGE.
41  *
42  *      @(#)subr_autoconf.c     8.1 (Berkeley) 6/10/93
43  *
44  * $FreeBSD: src/sys/kern/subr_autoconf.c,v 1.14 1999/10/05 21:19:41 n_hibma Exp $
45  */
46
47 #include <sys/param.h>
48 #include <sys/kernel.h>
49 #include <sys/systm.h>
50
51 /*
52  * Autoconfiguration subroutines.
53  */
54
55 /*
56  * "Interrupt driven config" functions.
57  */
58 static TAILQ_HEAD(, intr_config_hook) intr_config_hook_list =
59         TAILQ_HEAD_INITIALIZER(intr_config_hook_list);
60
61
62 /* ARGSUSED */
63 static void run_interrupt_driven_config_hooks __P((void *dummy));
64 static void
65 run_interrupt_driven_config_hooks(dummy)
66         void *dummy;
67 {
68         struct intr_config_hook *hook_entry, *next_entry;
69
70         for (hook_entry = TAILQ_FIRST(&intr_config_hook_list);
71              hook_entry != NULL;
72              hook_entry = next_entry) {
73                 next_entry = TAILQ_NEXT(hook_entry, ich_links);
74                 (*hook_entry->ich_func)(hook_entry->ich_arg);
75         }
76
77         while (!TAILQ_EMPTY(&intr_config_hook_list)) {
78                 tsleep(&intr_config_hook_list, PCONFIG, "conifhk", 0);
79         }
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         for (hook_entry = TAILQ_FIRST(&intr_config_hook_list);
96              hook_entry != NULL;
97              hook_entry = TAILQ_NEXT(hook_entry, ich_links))
98                 if (hook_entry == hook)
99                         break;
100         if (hook_entry != NULL) {
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         if (cold == 0)
107                 /* XXX Sufficient for modules loaded after initial config??? */
108                 run_interrupt_driven_config_hooks(NULL);        
109         return (0);
110 }
111
112 void
113 config_intrhook_disestablish(hook)
114         struct intr_config_hook *hook;
115 {
116         struct intr_config_hook *hook_entry;
117
118         for (hook_entry = TAILQ_FIRST(&intr_config_hook_list);
119              hook_entry != NULL;
120              hook_entry = TAILQ_NEXT(hook_entry, 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         /* Wakeup anyone watching the list */
129         wakeup(&intr_config_hook_list);
130 }