subr_autoconf.c revision 60833 
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: head/sys/kern/subr_autoconf.c 60833 2000-05-23 20:41:01Z jake $
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 */
58static TAILQ_HEAD(, struct intr_config_hook) intr_config_hook_list =
59	TAILQ_HEAD_INITIALIZER(intr_config_hook_list);
60
61
62/* ARGSUSED */
63static void run_interrupt_driven_config_hooks __P((void *dummy));
64static void
65run_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}
81SYSINIT(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 */
89int
90config_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
112void
113config_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}
131