subr_autoconf.c revision 116182 
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 */
45
46#include <sys/cdefs.h>
47__FBSDID("$FreeBSD: head/sys/kern/subr_autoconf.c 116182 2003-06-11 00:56:59Z obrien $");
48
49#include <sys/param.h>
50#include <sys/kernel.h>
51#include <sys/systm.h>
52
53/*
54 * Autoconfiguration subroutines.
55 */
56
57/*
58 * "Interrupt driven config" functions.
59 */
60static TAILQ_HEAD(, intr_config_hook) intr_config_hook_list =
61	TAILQ_HEAD_INITIALIZER(intr_config_hook_list);
62
63
64/* ARGSUSED */
65static void run_interrupt_driven_config_hooks(void *dummy);
66static void
67run_interrupt_driven_config_hooks(dummy)
68	void *dummy;
69{
70	struct intr_config_hook *hook_entry, *next_entry;
71
72	for (hook_entry = TAILQ_FIRST(&intr_config_hook_list);
73	     hook_entry != NULL;
74	     hook_entry = next_entry) {
75		next_entry = TAILQ_NEXT(hook_entry, ich_links);
76		(*hook_entry->ich_func)(hook_entry->ich_arg);
77	}
78
79	while (!TAILQ_EMPTY(&intr_config_hook_list)) {
80		tsleep(&intr_config_hook_list, PCONFIG, "conifhk", 0);
81	}
82}
83SYSINIT(intr_config_hooks, SI_SUB_INT_CONFIG_HOOKS, SI_ORDER_FIRST,
84	run_interrupt_driven_config_hooks, NULL)
85
86/*
87 * Register a hook that will be called after "cold"
88 * autoconfiguration is complete and interrupts can
89 * be used to complete initialization.
90 */
91int
92config_intrhook_establish(hook)
93	struct intr_config_hook *hook;
94{
95	struct intr_config_hook *hook_entry;
96
97	for (hook_entry = TAILQ_FIRST(&intr_config_hook_list);
98	     hook_entry != NULL;
99	     hook_entry = TAILQ_NEXT(hook_entry, ich_links))
100		if (hook_entry == hook)
101			break;
102	if (hook_entry != NULL) {
103		printf("config_intrhook_establish: establishing an "
104		       "already established hook.\n");
105		return (1);
106	}
107	TAILQ_INSERT_TAIL(&intr_config_hook_list, hook, ich_links);
108	if (cold == 0)
109		/* XXX Sufficient for modules loaded after initial config??? */
110		run_interrupt_driven_config_hooks(NULL);
111	return (0);
112}
113
114void
115config_intrhook_disestablish(hook)
116	struct intr_config_hook *hook;
117{
118	struct intr_config_hook *hook_entry;
119
120	for (hook_entry = TAILQ_FIRST(&intr_config_hook_list);
121	     hook_entry != NULL;
122	     hook_entry = TAILQ_NEXT(hook_entry, ich_links))
123		if (hook_entry == hook)
124			break;
125	if (hook_entry == NULL)
126		panic("config_intrhook_disestablish: disestablishing an "
127		      "unestablished hook");
128
129	TAILQ_REMOVE(&intr_config_hook_list, hook, ich_links);
130	/* Wakeup anyone watching the list */
131	wakeup(&intr_config_hook_list);
132}
133