1 /*- 2 * Copyright (c) 2000 Michael Smith 3 * Copyright (c) 2000 BSDi 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 * 27 * $FreeBSD$ 28 */ 29 30 /* 31 * 6.1 : Mutual Exclusion and Synchronisation 32 */ 33 34 #include "acpi.h" 35 36 #include "opt_acpi.h" 37 #include <sys/kernel.h> 38 #include <sys/malloc.h> 39 #include <sys/sysctl.h> 40 #if __FreeBSD_version >= 500000 41 #include <sys/lock.h> 42 #include <sys/mutex.h> 43 #endif 44 45 #define _COMPONENT ACPI_OS_SERVICES 46 ACPI_MODULE_NAME("SYNCH") 47 48 static MALLOC_DEFINE(M_ACPISEM, "acpisem", "ACPI semaphore"); 49 50 #if __FreeBSD_version < 500000 51 # define AS_LOCK(as) s = splhigh() 52 # define AS_UNLOCK(as) splx(s) 53 # define AS_LOCK_DECL int s 54 # define msleep(a, b, c, d, e) tsleep(a, c, d, e) 55 #else 56 # define AS_LOCK(as) mtx_lock(&(as)->as_mtx) 57 # define AS_UNLOCK(as) mtx_unlock(&(as)->as_mtx) 58 # define AS_LOCK_DECL 59 #endif 60 61 /* 62 * Simple counting semaphore implemented using a mutex. (Subsequently used 63 * in the OSI code to implement a mutex. Go figure.) 64 */ 65 struct acpi_semaphore { 66 #if __FreeBSD_version >= 500000 67 struct mtx as_mtx; 68 #endif 69 UINT32 as_units; 70 UINT32 as_maxunits; 71 UINT32 as_pendings; 72 UINT32 as_resetting; 73 UINT32 as_timeouts; 74 }; 75 76 #ifndef ACPI_NO_SEMAPHORES 77 #ifndef ACPI_SEMAPHORES_MAX_PENDING 78 #define ACPI_SEMAPHORES_MAX_PENDING 4 79 #endif 80 static int acpi_semaphore_debug = 0; 81 TUNABLE_INT("debug.acpi_semaphore_debug", &acpi_semaphore_debug); 82 SYSCTL_INT(_debug, OID_AUTO, acpi_semaphore_debug, CTLFLAG_RW, 83 &acpi_semaphore_debug, 0, ""); 84 #endif 85 86 ACPI_STATUS 87 AcpiOsCreateSemaphore(UINT32 MaxUnits, UINT32 InitialUnits, ACPI_HANDLE *OutHandle) 88 { 89 #ifndef ACPI_NO_SEMAPHORES 90 struct acpi_semaphore *as; 91 92 ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__); 93 94 if (OutHandle == NULL) 95 return(AE_BAD_PARAMETER); 96 if (InitialUnits > MaxUnits) 97 return_ACPI_STATUS(AE_BAD_PARAMETER); 98 99 if ((as = malloc(sizeof(*as), M_ACPISEM, M_NOWAIT)) == NULL) 100 return_ACPI_STATUS(AE_NO_MEMORY); 101 102 bzero(as, sizeof(*as)); 103 #if __FreeBSD_version >= 500000 104 mtx_init(&as->as_mtx, "ACPI semaphore", NULL, MTX_DEF); 105 #endif 106 as->as_units = InitialUnits; 107 as->as_maxunits = MaxUnits; 108 as->as_pendings = as->as_resetting = as->as_timeouts = 0; 109 110 ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, 111 "created semaphore %p max %d, initial %d\n", 112 as, InitialUnits, MaxUnits)); 113 114 *OutHandle = (ACPI_HANDLE)as; 115 return_ACPI_STATUS(AE_OK); 116 #else 117 *OutHandle = (ACPI_HANDLE)OutHandle; 118 return(AE_OK); 119 #endif 120 } 121 122 ACPI_STATUS 123 AcpiOsDeleteSemaphore (ACPI_HANDLE Handle) 124 { 125 #ifndef ACPI_NO_SEMAPHORES 126 struct acpi_semaphore *as = (struct acpi_semaphore *)Handle; 127 128 ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__); 129 130 ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "destroyed semaphore %p\n", as)); 131 #if __FreeBSD_version >= 500000 132 mtx_destroy(&as->as_mtx); 133 #endif 134 free(Handle, M_ACPISEM); 135 return_ACPI_STATUS(AE_OK); 136 #else 137 return(AE_OK); 138 #endif 139 } 140 141 /* 142 * This implementation has a bug, in that it has to stall for the entire 143 * timeout before it will return AE_TIME. A better implementation would 144 * use getmicrotime() to correctly adjust the timeout after being woken up. 145 */ 146 ACPI_STATUS 147 AcpiOsWaitSemaphore(ACPI_HANDLE Handle, UINT32 Units, UINT16 Timeout) 148 { 149 #ifndef ACPI_NO_SEMAPHORES 150 struct acpi_semaphore *as = (struct acpi_semaphore *)Handle; 151 ACPI_STATUS result; 152 int rv, tmo; 153 struct timeval timeouttv, currenttv, timelefttv; 154 AS_LOCK_DECL; 155 156 ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__); 157 158 if (as == NULL) 159 return_ACPI_STATUS(AE_BAD_PARAMETER); 160 161 if (cold) 162 return_ACPI_STATUS(AE_OK); 163 164 #if 0 165 if (as->as_units < Units && as->as_timeouts > 10) { 166 printf("%s: semaphore %p too many timeouts, resetting\n", __func__, as); 167 AS_LOCK(as); 168 as->as_units = as->as_maxunits; 169 if (as->as_pendings) 170 as->as_resetting = 1; 171 as->as_timeouts = 0; 172 wakeup(as); 173 AS_UNLOCK(as); 174 return_ACPI_STATUS(AE_TIME); 175 } 176 177 if (as->as_resetting) { 178 return_ACPI_STATUS(AE_TIME); 179 } 180 #endif 181 182 /* a timeout of ACPI_WAIT_FOREVER means "forever" */ 183 if (Timeout == ACPI_WAIT_FOREVER) { 184 tmo = 0; 185 timeouttv.tv_sec = ((0xffff/1000) + 1); /* cf. ACPI spec */ 186 timeouttv.tv_usec = 0; 187 } else { 188 /* compute timeout using microseconds per tick */ 189 tmo = (Timeout * 1000) / (1000000 / hz); 190 if (tmo <= 0) 191 tmo = 1; 192 timeouttv.tv_sec = Timeout / 1000; 193 timeouttv.tv_usec = (Timeout % 1000) * 1000; 194 } 195 196 /* calculate timeout value in timeval */ 197 getmicrotime(¤ttv); 198 timevaladd(&timeouttv, ¤ttv); 199 200 AS_LOCK(as); 201 ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, 202 "get %d units from semaphore %p (has %d), timeout %d\n", 203 Units, as, as->as_units, Timeout)); 204 for (;;) { 205 if (as->as_maxunits == ACPI_NO_UNIT_LIMIT) { 206 result = AE_OK; 207 break; 208 } 209 if (as->as_units >= Units) { 210 as->as_units -= Units; 211 result = AE_OK; 212 break; 213 } 214 215 /* limit number of pending treads */ 216 if (as->as_pendings >= ACPI_SEMAPHORES_MAX_PENDING) { 217 result = AE_TIME; 218 break; 219 } 220 221 /* if timeout values of zero is specified, return immediately */ 222 if (Timeout == 0) { 223 result = AE_TIME; 224 break; 225 } 226 227 #if __FreeBSD_version >= 500000 228 ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, 229 "semaphore blocked, calling msleep(%p, %p, %d, \"acsem\", %d)\n", 230 as, &as->as_mtx, PCATCH, tmo)); 231 #endif 232 233 as->as_pendings++; 234 235 if (acpi_semaphore_debug) { 236 printf("%s: Sleep %d, pending %d, semaphore %p, thread %d\n", 237 __func__, Timeout, as->as_pendings, as, AcpiOsGetThreadId()); 238 } 239 240 rv = msleep(as, &as->as_mtx, PCATCH, "acsem", tmo); 241 242 as->as_pendings--; 243 244 #if 0 245 if (as->as_resetting) { 246 /* semaphore reset, return immediately */ 247 if (as->as_pendings == 0) { 248 as->as_resetting = 0; 249 } 250 result = AE_TIME; 251 break; 252 } 253 #endif 254 255 ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "msleep(%d) returned %d\n", tmo, rv)); 256 if (rv == EWOULDBLOCK) { 257 result = AE_TIME; 258 break; 259 } 260 261 /* check if we already awaited enough */ 262 timelefttv = timeouttv; 263 getmicrotime(¤ttv); 264 timevalsub(&timelefttv, ¤ttv); 265 if (timelefttv.tv_sec < 0) { 266 ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "await semaphore %p timeout\n", as)); 267 result = AE_TIME; 268 break; 269 } 270 271 /* adjust timeout for the next sleep */ 272 tmo = (timelefttv.tv_sec * 1000000 + timelefttv.tv_usec) / (1000000 / hz); 273 if (tmo <= 0) 274 tmo = 1; 275 276 if (acpi_semaphore_debug) { 277 printf("%s: Wakeup timeleft(%lu, %lu), tmo %u, semaphore %p, thread %d\n", 278 __func__, timelefttv.tv_sec, timelefttv.tv_usec, tmo, as, AcpiOsGetThreadId()); 279 } 280 } 281 282 if (acpi_semaphore_debug) { 283 if (result == AE_TIME && Timeout > 0) { 284 printf("%s: Timeout %d, pending %d, semaphore %p\n", 285 __func__, Timeout, as->as_pendings, as); 286 } 287 if (result == AE_OK && (as->as_timeouts > 0 || as->as_pendings > 0)) { 288 printf("%s: Acquire %d, units %d, pending %d, semaphore %p, thread %d\n", 289 __func__, Units, as->as_units, as->as_pendings, as, AcpiOsGetThreadId()); 290 } 291 } 292 293 if (result == AE_TIME) { 294 as->as_timeouts++; 295 } else { 296 as->as_timeouts = 0; 297 } 298 299 AS_UNLOCK(as); 300 301 return_ACPI_STATUS(result); 302 #else 303 return(AE_OK); 304 #endif 305 } 306 307 ACPI_STATUS 308 AcpiOsSignalSemaphore(ACPI_HANDLE Handle, UINT32 Units) 309 { 310 #ifndef ACPI_NO_SEMAPHORES 311 struct acpi_semaphore *as = (struct acpi_semaphore *)Handle; 312 AS_LOCK_DECL; 313 314 ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__); 315 316 if (as == NULL) 317 return_ACPI_STATUS(AE_BAD_PARAMETER); 318 319 AS_LOCK(as); 320 ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, 321 "return %d units to semaphore %p (has %d)\n", 322 Units, as, as->as_units)); 323 if (as->as_maxunits != ACPI_NO_UNIT_LIMIT) { 324 as->as_units += Units; 325 if (as->as_units > as->as_maxunits) 326 as->as_units = as->as_maxunits; 327 } 328 329 if (acpi_semaphore_debug && (as->as_timeouts > 0 || as->as_pendings > 0)) { 330 printf("%s: Release %d, units %d, pending %d, semaphore %p, thread %d\n", 331 __func__, Units, as->as_units, as->as_pendings, as, AcpiOsGetThreadId()); 332 } 333 334 wakeup(as); 335 AS_UNLOCK(as); 336 return_ACPI_STATUS(AE_OK); 337 #else 338 return(AE_OK); 339 #endif 340 } 341 342 ACPI_STATUS 343 AcpiOsCreateLock (ACPI_HANDLE *OutHandle) 344 { 345 struct mtx *m; 346 347 if (OutHandle == NULL) 348 return (AE_BAD_PARAMETER); 349 MALLOC(m, struct mtx *, sizeof(*m), M_ACPISEM, M_NOWAIT | M_ZERO); 350 if (m == NULL) 351 return (AE_NO_MEMORY); 352 353 mtx_init(m, "acpica subsystem lock", NULL, MTX_DEF); 354 *OutHandle = (ACPI_HANDLE)m; 355 return (AE_OK); 356 } 357 358 void 359 AcpiOsDeleteLock (ACPI_HANDLE Handle) 360 { 361 struct mtx *m = (struct mtx *)Handle; 362 363 if (Handle == NULL) 364 return; 365 mtx_destroy(m); 366 } 367 368 /* 369 * The Flags parameter seems to state whether or not caller is an ISR 370 * (and thus can't block) but since we have ithreads, we don't worry 371 * about potentially blocking. 372 */ 373 void 374 AcpiOsAcquireLock (ACPI_HANDLE Handle, UINT32 Flags) 375 { 376 struct mtx *m = (struct mtx *)Handle; 377 378 if (Handle == NULL) 379 return; 380 mtx_lock(m); 381 } 382 383 void 384 AcpiOsReleaseLock (ACPI_HANDLE Handle, UINT32 Flags) 385 { 386 struct mtx *m = (struct mtx *)Handle; 387 388 if (Handle == NULL) 389 return; 390 mtx_unlock(m); 391 } 392