1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1992, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This software was developed by the Computer Systems Engineering group 8 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 9 * contributed to Berkeley. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. Neither the name of the University nor the names of its contributors 20 * may be used to endorse or promote products derived from this software 21 * without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33 * SUCH DAMAGE. 34 * 35 * @(#)subr_autoconf.c 8.1 (Berkeley) 6/10/93 36 * 37 */ 38 39 #include <sys/cdefs.h> 40 __FBSDID("$FreeBSD$"); 41 42 #include "opt_ddb.h" 43 44 #include <sys/param.h> 45 #include <sys/kernel.h> 46 #include <sys/linker.h> 47 #include <sys/lock.h> 48 #include <sys/malloc.h> 49 #include <sys/mutex.h> 50 #include <sys/systm.h> 51 52 /* 53 * Autoconfiguration subroutines. 54 */ 55 56 /* 57 * "Interrupt driven config" functions. 58 */ 59 static TAILQ_HEAD(, intr_config_hook) intr_config_hook_list = 60 TAILQ_HEAD_INITIALIZER(intr_config_hook_list); 61 static struct intr_config_hook *next_to_notify; 62 static struct mtx intr_config_hook_lock; 63 MTX_SYSINIT(intr_config_hook, &intr_config_hook_lock, "intr config", MTX_DEF); 64 65 /* ARGSUSED */ 66 static void run_interrupt_driven_config_hooks(void); 67 68 /* 69 * Private data and a shim function for implementing config_interhook_oneshot(). 70 */ 71 struct oneshot_config_hook { 72 struct intr_config_hook 73 och_hook; /* Must be first */ 74 ich_func_t och_func; 75 void *och_arg; 76 }; 77 78 static void 79 config_intrhook_oneshot_func(void *arg) 80 { 81 struct oneshot_config_hook *ohook; 82 83 ohook = arg; 84 ohook->och_func(ohook->och_arg); 85 config_intrhook_disestablish(&ohook->och_hook); 86 free(ohook, M_DEVBUF); 87 } 88 89 /* 90 * If we wait too long for an interrupt-driven config hook to return, print 91 * a diagnostic. 92 */ 93 #define WARNING_INTERVAL_SECS 60 94 static void 95 run_interrupt_driven_config_hooks_warning(int warned) 96 { 97 struct intr_config_hook *hook_entry; 98 char namebuf[64]; 99 long offset; 100 101 if (warned < 6) { 102 printf("run_interrupt_driven_hooks: still waiting after %d " 103 "seconds for", warned * WARNING_INTERVAL_SECS); 104 TAILQ_FOREACH(hook_entry, &intr_config_hook_list, ich_links) { 105 if (linker_search_symbol_name( 106 (caddr_t)hook_entry->ich_func, namebuf, 107 sizeof(namebuf), &offset) == 0) 108 printf(" %s", namebuf); 109 else 110 printf(" %p", hook_entry->ich_func); 111 } 112 printf("\n"); 113 } 114 KASSERT(warned < 6, 115 ("run_interrupt_driven_config_hooks: waited too long")); 116 } 117 118 static void 119 run_interrupt_driven_config_hooks() 120 { 121 static int running; 122 struct intr_config_hook *hook_entry; 123 124 mtx_lock(&intr_config_hook_lock); 125 126 /* 127 * If hook processing is already active, any newly 128 * registered hooks will eventually be notified. 129 * Let the currently running session issue these 130 * notifications. 131 */ 132 if (running != 0) { 133 mtx_unlock(&intr_config_hook_lock); 134 return; 135 } 136 running = 1; 137 138 while (next_to_notify != NULL) { 139 hook_entry = next_to_notify; 140 next_to_notify = TAILQ_NEXT(hook_entry, ich_links); 141 mtx_unlock(&intr_config_hook_lock); 142 (*hook_entry->ich_func)(hook_entry->ich_arg); 143 mtx_lock(&intr_config_hook_lock); 144 } 145 146 running = 0; 147 mtx_unlock(&intr_config_hook_lock); 148 } 149 150 static void 151 boot_run_interrupt_driven_config_hooks(void *dummy) 152 { 153 int warned; 154 155 run_interrupt_driven_config_hooks(); 156 157 /* Block boot processing until all hooks are disestablished. */ 158 mtx_lock(&intr_config_hook_lock); 159 warned = 0; 160 while (!TAILQ_EMPTY(&intr_config_hook_list)) { 161 if (msleep(&intr_config_hook_list, &intr_config_hook_lock, 162 0, "conifhk", WARNING_INTERVAL_SECS * hz) == 163 EWOULDBLOCK) { 164 mtx_unlock(&intr_config_hook_lock); 165 warned++; 166 run_interrupt_driven_config_hooks_warning(warned); 167 mtx_lock(&intr_config_hook_lock); 168 } 169 } 170 mtx_unlock(&intr_config_hook_lock); 171 } 172 173 SYSINIT(intr_config_hooks, SI_SUB_INT_CONFIG_HOOKS, SI_ORDER_FIRST, 174 boot_run_interrupt_driven_config_hooks, NULL); 175 176 /* 177 * Register a hook that will be called after "cold" 178 * autoconfiguration is complete and interrupts can 179 * be used to complete initialization. 180 */ 181 int 182 config_intrhook_establish(struct intr_config_hook *hook) 183 { 184 struct intr_config_hook *hook_entry; 185 186 mtx_lock(&intr_config_hook_lock); 187 TAILQ_FOREACH(hook_entry, &intr_config_hook_list, ich_links) 188 if (hook_entry == hook) 189 break; 190 if (hook_entry != NULL) { 191 mtx_unlock(&intr_config_hook_lock); 192 printf("config_intrhook_establish: establishing an " 193 "already established hook.\n"); 194 return (1); 195 } 196 TAILQ_INSERT_TAIL(&intr_config_hook_list, hook, ich_links); 197 if (next_to_notify == NULL) 198 next_to_notify = hook; 199 mtx_unlock(&intr_config_hook_lock); 200 if (cold == 0) 201 /* 202 * XXX Call from a task since not all drivers expect 203 * to be re-entered at the time a hook is established. 204 */ 205 /* XXX Sufficient for modules loaded after initial config??? */ 206 run_interrupt_driven_config_hooks(); 207 return (0); 208 } 209 210 /* 211 * Register a hook function that is automatically unregistered after it runs. 212 */ 213 void 214 config_intrhook_oneshot(ich_func_t func, void *arg) 215 { 216 struct oneshot_config_hook *ohook; 217 218 ohook = malloc(sizeof(*ohook), M_DEVBUF, M_WAITOK); 219 ohook->och_func = func; 220 ohook->och_arg = arg; 221 ohook->och_hook.ich_func = config_intrhook_oneshot_func; 222 ohook->och_hook.ich_arg = ohook; 223 config_intrhook_establish(&ohook->och_hook); 224 } 225 226 void 227 config_intrhook_disestablish(struct intr_config_hook *hook) 228 { 229 struct intr_config_hook *hook_entry; 230 231 mtx_lock(&intr_config_hook_lock); 232 TAILQ_FOREACH(hook_entry, &intr_config_hook_list, ich_links) 233 if (hook_entry == hook) 234 break; 235 if (hook_entry == NULL) 236 panic("config_intrhook_disestablish: disestablishing an " 237 "unestablished hook"); 238 239 if (next_to_notify == hook) 240 next_to_notify = TAILQ_NEXT(hook, ich_links); 241 TAILQ_REMOVE(&intr_config_hook_list, hook, ich_links); 242 243 /* Wakeup anyone watching the list */ 244 wakeup(&intr_config_hook_list); 245 mtx_unlock(&intr_config_hook_lock); 246 } 247 248 #ifdef DDB 249 #include <ddb/ddb.h> 250 251 DB_SHOW_COMMAND(conifhk, db_show_conifhk) 252 { 253 struct intr_config_hook *hook_entry; 254 char namebuf[64]; 255 long offset; 256 257 TAILQ_FOREACH(hook_entry, &intr_config_hook_list, ich_links) { 258 if (linker_ddb_search_symbol_name( 259 (caddr_t)hook_entry->ich_func, namebuf, sizeof(namebuf), 260 &offset) == 0) { 261 db_printf("hook: %p at %s+%#lx arg: %p\n", 262 hook_entry->ich_func, namebuf, offset, 263 hook_entry->ich_arg); 264 } else { 265 db_printf("hook: %p at ??+?? arg %p\n", 266 hook_entry->ich_func, hook_entry->ich_arg); 267 } 268 } 269 } 270 #endif /* DDB */ 271