xref: /freebsd/sys/kern/subr_autoconf.c (revision ba54cdcdda639bebc917b1796ecbc35a83ff8625)
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/systm.h>
43 
44 /*
45  * Autoconfiguration subroutines.
46  */
47 
48 /*
49  * "Interrupt driven config" functions.
50  */
51 static TAILQ_HEAD(, intr_config_hook) intr_config_hook_list =
52 	TAILQ_HEAD_INITIALIZER(intr_config_hook_list);
53 
54 
55 /* ARGSUSED */
56 static void run_interrupt_driven_config_hooks(void *dummy);
57 static void
58 run_interrupt_driven_config_hooks(dummy)
59 	void *dummy;
60 {
61 	struct intr_config_hook *hook_entry, *next_entry;
62 
63 	for (hook_entry = TAILQ_FIRST(&intr_config_hook_list);
64 	     hook_entry != NULL;
65 	     hook_entry = next_entry) {
66 		next_entry = TAILQ_NEXT(hook_entry, ich_links);
67 		(*hook_entry->ich_func)(hook_entry->ich_arg);
68 	}
69 
70 	while (!TAILQ_EMPTY(&intr_config_hook_list)) {
71 		tsleep(&intr_config_hook_list, PCONFIG, "conifhk", 0);
72 	}
73 }
74 SYSINIT(intr_config_hooks, SI_SUB_INT_CONFIG_HOOKS, SI_ORDER_FIRST,
75 	run_interrupt_driven_config_hooks, NULL)
76 
77 /*
78  * Register a hook that will be called after "cold"
79  * autoconfiguration is complete and interrupts can
80  * be used to complete initialization.
81  */
82 int
83 config_intrhook_establish(hook)
84 	struct intr_config_hook *hook;
85 {
86 	struct intr_config_hook *hook_entry;
87 
88 	for (hook_entry = TAILQ_FIRST(&intr_config_hook_list);
89 	     hook_entry != NULL;
90 	     hook_entry = TAILQ_NEXT(hook_entry, ich_links))
91 		if (hook_entry == hook)
92 			break;
93 	if (hook_entry != NULL) {
94 		printf("config_intrhook_establish: establishing an "
95 		       "already established hook.\n");
96 		return (1);
97 	}
98 	TAILQ_INSERT_TAIL(&intr_config_hook_list, hook, ich_links);
99 	if (cold == 0)
100 		/* XXX Sufficient for modules loaded after initial config??? */
101 		run_interrupt_driven_config_hooks(NULL);
102 	return (0);
103 }
104 
105 void
106 config_intrhook_disestablish(hook)
107 	struct intr_config_hook *hook;
108 {
109 	struct intr_config_hook *hook_entry;
110 
111 	for (hook_entry = TAILQ_FIRST(&intr_config_hook_list);
112 	     hook_entry != NULL;
113 	     hook_entry = TAILQ_NEXT(hook_entry, ich_links))
114 		if (hook_entry == hook)
115 			break;
116 	if (hook_entry == NULL)
117 		panic("config_intrhook_disestablish: disestablishing an "
118 		      "unestablished hook");
119 
120 	TAILQ_REMOVE(&intr_config_hook_list, hook, ich_links);
121 	/* Wakeup anyone watching the list */
122 	wakeup(&intr_config_hook_list);
123 }
124