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: src/sys/dev/acpica/Osd/OsdSynch.c,v 1.21 2004/05/05 20:07:52 njl Exp $ 28 */ 29 30 /* 31 * 6.1 : Mutual Exclusion and Synchronisation 32 */ 33 34 #include "acpi.h" 35 #include "accommon.h" 36 37 #include "opt_acpi.h" 38 39 #include <sys/kernel.h> 40 #include <sys/malloc.h> 41 #include <sys/sysctl.h> 42 #include <sys/lock.h> 43 #include <sys/thread.h> 44 #include <sys/thread2.h> 45 #include <sys/spinlock2.h> 46 47 #define _COMPONENT ACPI_OS_SERVICES 48 ACPI_MODULE_NAME("SYNCH") 49 50 MALLOC_DEFINE(M_ACPISEM, "acpisem", "ACPI semaphore"); 51 52 #define AS_LOCK(as) spin_lock(&(as)->as_spin) 53 #define AS_UNLOCK(as) spin_unlock(&(as)->as_spin) 54 #define AS_LOCK_DECL 55 56 /* 57 * Simple counting semaphore implemented using a mutex. (Subsequently used 58 * in the OSI code to implement a mutex. Go figure.) 59 */ 60 struct acpi_semaphore { 61 struct spinlock as_spin; 62 UINT32 as_units; 63 UINT32 as_maxunits; 64 UINT32 as_pendings; 65 UINT32 as_resetting; 66 UINT32 as_timeouts; 67 }; 68 69 #ifndef ACPI_NO_SEMAPHORES 70 #ifndef ACPI_SEMAPHORES_MAX_PENDING 71 #define ACPI_SEMAPHORES_MAX_PENDING 4 72 #endif 73 static int acpi_semaphore_debug = 0; 74 TUNABLE_INT("debug.acpi_semaphore_debug", &acpi_semaphore_debug); 75 SYSCTL_DECL(_debug_acpi); 76 SYSCTL_INT(_debug_acpi, OID_AUTO, semaphore_debug, CTLFLAG_RW, 77 &acpi_semaphore_debug, 0, "Enable ACPI semaphore debug messages"); 78 #endif /* !ACPI_NO_SEMAPHORES */ 79 80 ACPI_STATUS 81 AcpiOsCreateSemaphore(UINT32 MaxUnits, UINT32 InitialUnits, 82 ACPI_HANDLE *OutHandle) 83 { 84 #ifndef ACPI_NO_SEMAPHORES 85 struct acpi_semaphore *as; 86 87 ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__); 88 89 if (OutHandle == NULL) 90 return_ACPI_STATUS (AE_BAD_PARAMETER); 91 if (InitialUnits > MaxUnits) 92 return_ACPI_STATUS (AE_BAD_PARAMETER); 93 94 as = kmalloc(sizeof(*as), M_ACPISEM, M_INTWAIT | M_ZERO); 95 96 spin_init(&as->as_spin); 97 as->as_units = InitialUnits; 98 as->as_maxunits = MaxUnits; 99 as->as_pendings = as->as_resetting = as->as_timeouts = 0; 100 101 ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, 102 "created semaphore %p max %d, initial %d\n", 103 as, InitialUnits, MaxUnits)); 104 105 *OutHandle = (ACPI_HANDLE)as; 106 #else 107 *OutHandle = (ACPI_HANDLE)OutHandle; 108 #endif /* !ACPI_NO_SEMAPHORES */ 109 110 return_ACPI_STATUS (AE_OK); 111 } 112 113 ACPI_STATUS 114 AcpiOsDeleteSemaphore(ACPI_HANDLE Handle) 115 { 116 #ifndef ACPI_NO_SEMAPHORES 117 struct acpi_semaphore *as = (struct acpi_semaphore *)Handle; 118 119 ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__); 120 121 ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "destroyed semaphore %p\n", as)); 122 spin_uninit(&as->as_spin); 123 kfree(as, M_ACPISEM); 124 #endif /* !ACPI_NO_SEMAPHORES */ 125 126 return_ACPI_STATUS (AE_OK); 127 } 128 129 ACPI_STATUS 130 AcpiOsWaitSemaphore(ACPI_HANDLE Handle, UINT32 Units, UINT16 Timeout) 131 { 132 #ifndef ACPI_NO_SEMAPHORES 133 ACPI_STATUS result; 134 struct acpi_semaphore *as = (struct acpi_semaphore *)Handle; 135 int rv, tmo; 136 struct timeval timeouttv, currenttv, timelefttv; 137 AS_LOCK_DECL; 138 139 ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__); 140 141 if (as == NULL) 142 return_ACPI_STATUS (AE_BAD_PARAMETER); 143 144 if (cold) 145 return_ACPI_STATUS (AE_OK); 146 147 #if 0 148 if (as->as_units < Units && as->as_timeouts > 10) { 149 kprintf("%s: semaphore %p too many timeouts, resetting\n", __func__, as); 150 AS_LOCK(as); 151 as->as_units = as->as_maxunits; 152 if (as->as_pendings) 153 as->as_resetting = 1; 154 as->as_timeouts = 0; 155 wakeup(as); 156 AS_UNLOCK(as); 157 return_ACPI_STATUS (AE_TIME); 158 } 159 160 if (as->as_resetting) 161 return_ACPI_STATUS (AE_TIME); 162 #endif 163 164 /* a timeout of ACPI_WAIT_FOREVER means "forever" */ 165 if (Timeout == ACPI_WAIT_FOREVER) { 166 tmo = 0; 167 timeouttv.tv_sec = ((0xffff/1000) + 1); /* cf. ACPI spec */ 168 timeouttv.tv_usec = 0; 169 } else { 170 /* compute timeout using microseconds per tick */ 171 tmo = (Timeout * 1000) / (1000000 / hz); 172 if (tmo <= 0) 173 tmo = 1; 174 timeouttv.tv_sec = Timeout / 1000; 175 timeouttv.tv_usec = (Timeout % 1000) * 1000; 176 } 177 178 /* calculate timeout value in timeval */ 179 getmicrouptime(¤ttv); 180 timevaladd(&timeouttv, ¤ttv); 181 182 AS_LOCK(as); 183 ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, 184 "get %d units from semaphore %p (has %d), timeout %d\n", 185 Units, as, as->as_units, Timeout)); 186 for (;;) { 187 if (as->as_maxunits == ACPI_NO_UNIT_LIMIT) { 188 result = AE_OK; 189 break; 190 } 191 if (as->as_units >= Units) { 192 as->as_units -= Units; 193 result = AE_OK; 194 break; 195 } 196 197 /* limit number of pending treads */ 198 if (as->as_pendings >= ACPI_SEMAPHORES_MAX_PENDING) { 199 result = AE_TIME; 200 break; 201 } 202 203 /* if timeout values of zero is specified, return immediately */ 204 if (Timeout == 0) { 205 result = AE_TIME; 206 break; 207 } 208 209 ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, 210 "semaphore blocked, calling ssleep(%p, %p, %d, \"acsem\", %d)\n", 211 as, &as->as_spin, PCATCH, tmo)); 212 213 as->as_pendings++; 214 215 if (acpi_semaphore_debug) { 216 kprintf("%s: Sleep %jd, pending %jd, semaphore %p, thread %jd\n", 217 __func__, (intmax_t)Timeout, 218 (intmax_t)as->as_pendings, as, 219 (intmax_t)AcpiOsGetThreadId()); 220 } 221 222 rv = ssleep(as, &as->as_spin, PCATCH, "acsem", tmo); 223 224 as->as_pendings--; 225 226 #if 0 227 if (as->as_resetting) { 228 /* semaphore reset, return immediately */ 229 if (as->as_pendings == 0) { 230 as->as_resetting = 0; 231 } 232 result = AE_TIME; 233 break; 234 } 235 #endif 236 237 ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "ssleep(%d) returned %d\n", tmo, rv)); 238 if (rv == EWOULDBLOCK) { 239 result = AE_TIME; 240 break; 241 } 242 243 /* check if we already awaited enough */ 244 timelefttv = timeouttv; 245 getmicrouptime(¤ttv); 246 timevalsub(&timelefttv, ¤ttv); 247 if (timelefttv.tv_sec < 0) { 248 ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "await semaphore %p timeout\n", 249 as)); 250 result = AE_TIME; 251 break; 252 } 253 254 /* adjust timeout for the next sleep */ 255 tmo = (timelefttv.tv_sec * 1000000 + timelefttv.tv_usec) / 256 (1000000 / hz); 257 if (tmo <= 0) 258 tmo = 1; 259 260 if (acpi_semaphore_debug) { 261 kprintf("%s: Wakeup timeleft(%ju, %ju), tmo %ju, sem %p, thread %jd\n", 262 __func__, 263 (intmax_t)timelefttv.tv_sec, (intmax_t)timelefttv.tv_usec, 264 (intmax_t)tmo, as, (intmax_t)AcpiOsGetThreadId()); 265 } 266 } 267 268 if (acpi_semaphore_debug) { 269 if (result == AE_TIME && Timeout > 0) { 270 kprintf("%s: Timeout %d, pending %d, semaphore %p\n", 271 __func__, Timeout, as->as_pendings, as); 272 } 273 if (result == AE_OK && (as->as_timeouts > 0 || as->as_pendings > 0)) { 274 kprintf("%s: Acquire %d, units %d, pending %d, sem %p, thread %jd\n", 275 __func__, Units, as->as_units, as->as_pendings, as, 276 (intmax_t)AcpiOsGetThreadId()); 277 } 278 } 279 280 if (result == AE_TIME) 281 as->as_timeouts++; 282 else 283 as->as_timeouts = 0; 284 285 AS_UNLOCK(as); 286 return_ACPI_STATUS (result); 287 #else 288 return_ACPI_STATUS (AE_OK); 289 #endif /* !ACPI_NO_SEMAPHORES */ 290 } 291 292 ACPI_STATUS 293 AcpiOsSignalSemaphore(ACPI_HANDLE Handle, UINT32 Units) 294 { 295 #ifndef ACPI_NO_SEMAPHORES 296 struct acpi_semaphore *as = (struct acpi_semaphore *)Handle; 297 AS_LOCK_DECL; 298 299 ACPI_FUNCTION_TRACE((char *)(uintptr_t)__func__); 300 301 if (as == NULL) 302 return_ACPI_STATUS(AE_BAD_PARAMETER); 303 304 AS_LOCK(as); 305 ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, 306 "return %d units to semaphore %p (has %d)\n", 307 Units, as, as->as_units)); 308 if (as->as_maxunits != ACPI_NO_UNIT_LIMIT) { 309 as->as_units += Units; 310 if (as->as_units > as->as_maxunits) 311 as->as_units = as->as_maxunits; 312 } 313 314 if (acpi_semaphore_debug && (as->as_timeouts > 0 || as->as_pendings > 0)) { 315 kprintf("%s: Release %d, units %d, pending %d, semaphore %p, thread %jd\n", 316 __func__, Units, as->as_units, as->as_pendings, as, 317 (intmax_t)AcpiOsGetThreadId()); 318 } 319 320 wakeup(as); 321 AS_UNLOCK(as); 322 #endif /* !ACPI_NO_SEMAPHORES */ 323 324 return_ACPI_STATUS (AE_OK); 325 } 326 327 struct acpi_spinlock { 328 struct spinlock lock; 329 #ifdef ACPI_DEBUG_LOCKS 330 thread_t owner; 331 const char *func; 332 int line; 333 #endif 334 }; 335 336 ACPI_STATUS 337 AcpiOsCreateLock(ACPI_SPINLOCK *OutHandle) 338 { 339 ACPI_SPINLOCK spin; 340 341 if (OutHandle == NULL) 342 return (AE_BAD_PARAMETER); 343 spin = kmalloc(sizeof(*spin), M_ACPISEM, M_INTWAIT|M_ZERO); 344 spin_init(&spin->lock); 345 #ifdef ACPI_DEBUG_LOCKS 346 spin->owner = NULL; 347 spin->func = ""; 348 spin->line = 0; 349 #endif 350 *OutHandle = spin; 351 return (AE_OK); 352 } 353 354 void 355 AcpiOsDeleteLock (ACPI_SPINLOCK Spin) 356 { 357 if (Spin == NULL) 358 return; 359 spin_uninit(&Spin->lock); 360 kfree(Spin, M_ACPISEM); 361 } 362 363 /* 364 * OS-dependent locking primitives. These routines should be able to be 365 * called from an interrupt-handler or cpu_idle thread. 366 * 367 * NB: some of ACPI-CA functions with locking flags, say AcpiSetRegister(), 368 * are changed to unconditionally call AcpiOsAcquireLock/AcpiOsReleaseLock. 369 */ 370 ACPI_CPU_FLAGS 371 #ifdef ACPI_DEBUG_LOCKS 372 _AcpiOsAcquireLock (ACPI_SPINLOCK Spin, const char *func, int line) 373 #else 374 AcpiOsAcquireLock (ACPI_SPINLOCK Spin) 375 #endif 376 { 377 spin_lock(&Spin->lock); 378 379 #ifdef ACPI_DEBUG_LOCKS 380 if (Spin->owner) { 381 kprintf("%p(%s:%d): acpi_spinlock %p already held by %p(%s:%d)\n", 382 curthread, func, line, Spin, Spin->owner, Spin->func, 383 Spin->line); 384 print_backtrace(-1); 385 } else { 386 Spin->owner = curthread; 387 Spin->func = func; 388 Spin->line = line; 389 } 390 #endif 391 return(0); 392 } 393 394 void 395 AcpiOsReleaseLock (ACPI_SPINLOCK Spin, ACPI_CPU_FLAGS Flags) 396 { 397 #ifdef ACPI_DEBUG_LOCKS 398 if (Flags) { 399 if (Spin->owner != NULL) { 400 kprintf("%p: acpi_spinlock %p is unexectedly held by %p(%s:%d)\n", 401 curthread, Spin, Spin->owner, Spin->func, Spin->line); 402 print_backtrace(-1); 403 } else 404 return; 405 } 406 Spin->owner = NULL; 407 Spin->func = ""; 408 Spin->line = 0; 409 #endif 410 spin_unlock(&Spin->lock); 411 } 412 413 /* Section 5.2.9.1: global lock acquire/release functions */ 414 #define GL_ACQUIRED (-1) 415 #define GL_BUSY 0 416 #define GL_BIT_PENDING 0x1 417 #define GL_BIT_OWNED 0x2 418 #define GL_BIT_MASK (GL_BIT_PENDING | GL_BIT_OWNED) 419 420 /* 421 * Acquire the global lock. If busy, set the pending bit. The caller 422 * will wait for notification from the BIOS that the lock is available 423 * and then attempt to acquire it again. 424 */ 425 int 426 acpi_acquire_global_lock(uint32_t *lock) 427 { 428 uint32_t new, old; 429 430 do { 431 old = *lock; 432 new = ((old & ~GL_BIT_MASK) | GL_BIT_OWNED) | 433 ((old >> 1) & GL_BIT_PENDING); 434 } while (atomic_cmpset_int(lock, old, new) == 0); 435 436 return ((new < GL_BIT_MASK) ? GL_ACQUIRED : GL_BUSY); 437 } 438 439 /* 440 * Release the global lock, returning whether there is a waiter pending. 441 * If the BIOS set the pending bit, OSPM must notify the BIOS when it 442 * releases the lock. 443 */ 444 int 445 acpi_release_global_lock(uint32_t *lock) 446 { 447 uint32_t new, old; 448 449 do { 450 old = *lock; 451 new = old & ~GL_BIT_MASK; 452 } while (atomic_cmpset_int(lock, old, new) == 0); 453 454 return (old & GL_BIT_PENDING); 455 } 456