drivers/acpi/executer/exsystem.c

   1
   2 /******************************************************************************
   3  *
   4  * Module Name: exsystem - Interface to OS services
   5  *
   6  *****************************************************************************/
   7
   8 /*
   9  * Copyright (C) 2000 - 2006, R. Byron Moore
  10  * All rights reserved.
  11  *
  12  * Redistribution and use in source and binary forms, with or without
  13  * modification, are permitted provided that the following conditions
  14  * are met:
  15  * 1. Redistributions of source code must retain the above copyright
  16  *    notice, this list of conditions, and the following disclaimer,
  17  *    without modification.
  18  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  19  *    substantially similar to the "NO WARRANTY" disclaimer below
  20  *    ("Disclaimer") and any redistribution must be conditioned upon
  21  *    including a substantially similar Disclaimer requirement for further
  22  *    binary redistribution.
  23  * 3. Neither the names of the above-listed copyright holders nor the names
  24  *    of any contributors may be used to endorse or promote products derived
  25  *    from this software without specific prior written permission.
  26  *
  27  * Alternatively, this software may be distributed under the terms of the
  28  * GNU General Public License ("GPL") version 2 as published by the Free
  29  * Software Foundation.
  30  *
  31  * NO WARRANTY
  32  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  33  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  34  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  35  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  36  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  37  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  38  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  39  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  40  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  41  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  42  * POSSIBILITY OF SUCH DAMAGES.
  43  */
  44
  45 #include <acpi/acpi.h>
  46 #include <acpi/acinterp.h>
  47 #include <acpi/acevents.h>
  48
  49 #define _COMPONENT          ACPI_EXECUTER
  50 ACPI_MODULE_NAME("exsystem")
  51
  52 /*******************************************************************************
  53  *
  54  * FUNCTION:    acpi_ex_system_wait_semaphore
  55  *
  56  * PARAMETERS:  Semaphore       - Semaphore to wait on
  57  *              Timeout         - Max time to wait
  58  *
  59  * RETURN:      Status
  60  *
  61  * DESCRIPTION: Implements a semaphore wait with a check to see if the
  62  *              semaphore is available immediately.  If it is not, the
  63  *              interpreter is released.
  64  *
  65  ******************************************************************************/
  66 acpi_status acpi_ex_system_wait_semaphore(acpi_semaphore semaphore, u16 timeout)
  67 {
  68         acpi_status status;
  69         acpi_status status2;
  70
  71         ACPI_FUNCTION_TRACE(ex_system_wait_semaphore);
  72
  73         status = acpi_os_wait_semaphore(semaphore, 1, ACPI_DO_NOT_WAIT);
  74         if (ACPI_SUCCESS(status)) {
  75                 return_ACPI_STATUS(status);
  76         }
  77
  78         if (status == AE_TIME) {
  79
  80                 /* We must wait, so unlock the interpreter */
  81
  82                 acpi_ex_exit_interpreter();
  83
  84                 status = acpi_os_wait_semaphore(semaphore, 1, timeout);
  85
  86                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
  87                                   "*** Thread awake after blocking, %s\n",
  88                                   acpi_format_exception(status)));
  89
  90                 /* Reacquire the interpreter */
  91
  92                 status2 = acpi_ex_enter_interpreter();
  93                 if (ACPI_FAILURE(status2)) {
  94
  95                         /* Report fatal error, could not acquire interpreter */
  96
  97                         return_ACPI_STATUS(status2);
  98                 }
  99         }
 100
 101         return_ACPI_STATUS(status);
 102 }
 103
 104 /*******************************************************************************
 105  *
 106  * FUNCTION:    acpi_ex_system_wait_mutex
 107  *
 108  * PARAMETERS:  Mutex           - Mutex to wait on
 109  *              Timeout         - Max time to wait
 110  *
 111  * RETURN:      Status
 112  *
 113  * DESCRIPTION: Implements a semaphore wait with a check to see if the
 114  *              semaphore is available immediately.  If it is not, the
 115  *              interpreter is released.
 116  *
 117  ******************************************************************************/
 118
 119 acpi_status acpi_ex_system_wait_mutex(acpi_mutex mutex, u16 timeout)
 120 {
 121         acpi_status status;
 122         acpi_status status2;
 123
 124         ACPI_FUNCTION_TRACE(ex_system_wait_mutex);
 125
 126         status = acpi_os_acquire_mutex(mutex, ACPI_DO_NOT_WAIT);
 127         if (ACPI_SUCCESS(status)) {
 128                 return_ACPI_STATUS(status);
 129         }
 130
 131         if (status == AE_TIME) {
 132
 133                 /* We must wait, so unlock the interpreter */
 134
 135                 acpi_ex_exit_interpreter();
 136
 137                 status = acpi_os_acquire_mutex(mutex, timeout);
 138
 139                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 140                                   "*** Thread awake after blocking, %s\n",
 141                                   acpi_format_exception(status)));
 142
 143                 /* Reacquire the interpreter */
 144
 145                 status2 = acpi_ex_enter_interpreter();
 146                 if (ACPI_FAILURE(status2)) {
 147
 148                         /* Report fatal error, could not acquire interpreter */
 149
 150                         return_ACPI_STATUS(status2);
 151                 }
 152         }
 153
 154         return_ACPI_STATUS(status);
 155 }
 156
 157 /*******************************************************************************
 158  *
 159  * FUNCTION:    acpi_ex_system_do_stall
 160  *
 161  * PARAMETERS:  how_long        - The amount of time to stall,
 162  *                                in microseconds
 163  *
 164  * RETURN:      Status
 165  *
 166  * DESCRIPTION: Suspend running thread for specified amount of time.
 167  *              Note: ACPI specification requires that Stall() does not
 168  *              relinquish the processor, and delays longer than 100 usec
 169  *              should use Sleep() instead.  We allow stalls up to 255 usec
 170  *              for compatibility with other interpreters and existing BIOSs.
 171  *
 172  ******************************************************************************/
 173
 174 acpi_status acpi_ex_system_do_stall(u32 how_long)
 175 {
 176         acpi_status status = AE_OK;
 177
 178         ACPI_FUNCTION_ENTRY();
 179
 180         if (how_long > 255) {   /* 255 microseconds */
 181                 /*
 182                  * Longer than 255 usec, this is an error
 183                  *
 184                  * (ACPI specifies 100 usec as max, but this gives some slack in
 185                  * order to support existing BIOSs)
 186                  */
 187                 ACPI_ERROR((AE_INFO, "Time parameter is too large (%d)",
 188                             how_long));
 189                 status = AE_AML_OPERAND_VALUE;
 190         } else {
 191                 acpi_os_stall(how_long);
 192         }
 193
 194         return (status);
 195 }
 196
 197 /*******************************************************************************
 198  *
 199  * FUNCTION:    acpi_ex_system_do_suspend
 200  *
 201  * PARAMETERS:  how_long        - The amount of time to suspend,
 202  *                                in milliseconds
 203  *
 204  * RETURN:      None
 205  *
 206  * DESCRIPTION: Suspend running thread for specified amount of time.
 207  *
 208  ******************************************************************************/
 209
 210 acpi_status acpi_ex_system_do_suspend(acpi_integer how_long)
 211 {
 212         acpi_status status;
 213
 214         ACPI_FUNCTION_ENTRY();
 215
 216         /* Since this thread will sleep, we must release the interpreter */
 217
 218         acpi_ex_exit_interpreter();
 219
 220         acpi_os_sleep(how_long);
 221
 222         /* And now we must get the interpreter again */
 223
 224         status = acpi_ex_enter_interpreter();
 225         return (status);
 226 }
 227
 228 /*******************************************************************************
 229  *
 230  * FUNCTION:    acpi_ex_system_acquire_mutex
 231  *
 232  * PARAMETERS:  time_desc       - Maximum time to wait for the mutex
 233  *              obj_desc        - The object descriptor for this op
 234  *
 235  * RETURN:      Status
 236  *
 237  * DESCRIPTION: Provides an access point to perform synchronization operations
 238  *              within the AML.  This function will cause a lock to be generated
 239  *              for the Mutex pointed to by obj_desc.
 240  *
 241  ******************************************************************************/
 242
 243 acpi_status
 244 acpi_ex_system_acquire_mutex(union acpi_operand_object * time_desc,
 245                              union acpi_operand_object * obj_desc)
 246 {
 247         acpi_status status = AE_OK;
 248
 249         ACPI_FUNCTION_TRACE_PTR(ex_system_acquire_mutex, obj_desc);
 250
 251         if (!obj_desc) {
 252                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 253         }
 254
 255         /* Support for the _GL_ Mutex object -- go get the global lock */
 256
 257         if (obj_desc->mutex.os_mutex == ACPI_GLOBAL_LOCK) {
 258                 status =
 259                     acpi_ev_acquire_global_lock((u16) time_desc->integer.value);
 260                 return_ACPI_STATUS(status);
 261         }
 262
 263         status = acpi_ex_system_wait_mutex(obj_desc->mutex.os_mutex,
 264                                            (u16) time_desc->integer.value);
 265         return_ACPI_STATUS(status);
 266 }
 267
 268 /*******************************************************************************
 269  *
 270  * FUNCTION:    acpi_ex_system_release_mutex
 271  *
 272  * PARAMETERS:  obj_desc        - The object descriptor for this op
 273  *
 274  * RETURN:      Status
 275  *
 276  * DESCRIPTION: Provides an access point to perform synchronization operations
 277  *              within the AML.  This operation is a request to release a
 278  *              previously acquired Mutex.  If the Mutex variable is set then
 279  *              it will be decremented.
 280  *
 281  ******************************************************************************/
 282
 283 acpi_status acpi_ex_system_release_mutex(union acpi_operand_object *obj_desc)
 284 {
 285         acpi_status status = AE_OK;
 286
 287         ACPI_FUNCTION_TRACE(ex_system_release_mutex);
 288
 289         if (!obj_desc) {
 290                 return_ACPI_STATUS(AE_BAD_PARAMETER);
 291         }
 292
 293         /* Support for the _GL_ Mutex object -- release the global lock */
 294
 295         if (obj_desc->mutex.os_mutex == ACPI_GLOBAL_LOCK) {
 296                 status = acpi_ev_release_global_lock();
 297                 return_ACPI_STATUS(status);
 298         }
 299
 300         acpi_os_release_mutex(obj_desc->mutex.os_mutex);
 301         return_ACPI_STATUS(AE_OK);
 302 }
 303
 304 /*******************************************************************************
 305  *
 306  * FUNCTION:    acpi_ex_system_signal_event
 307  *
 308  * PARAMETERS:  obj_desc        - The object descriptor for this op
 309  *
 310  * RETURN:      Status
 311  *
 312  * DESCRIPTION: Provides an access point to perform synchronization operations
 313  *              within the AML.
 314  *
 315  ******************************************************************************/
 316
 317 acpi_status acpi_ex_system_signal_event(union acpi_operand_object *obj_desc)
 318 {
 319         acpi_status status = AE_OK;
 320
 321         ACPI_FUNCTION_TRACE(ex_system_signal_event);
 322
 323         if (obj_desc) {
 324                 status =
 325                     acpi_os_signal_semaphore(obj_desc->event.os_semaphore, 1);
 326         }
 327
 328         return_ACPI_STATUS(status);
 329 }
 330
 331 /*******************************************************************************
 332  *
 333  * FUNCTION:    acpi_ex_system_wait_event
 334  *
 335  * PARAMETERS:  time_desc       - The 'time to delay' object descriptor
 336  *              obj_desc        - The object descriptor for this op
 337  *
 338  * RETURN:      Status
 339  *
 340  * DESCRIPTION: Provides an access point to perform synchronization operations
 341  *              within the AML.  This operation is a request to wait for an
 342  *              event.
 343  *
 344  ******************************************************************************/
 345
 346 acpi_status
 347 acpi_ex_system_wait_event(union acpi_operand_object *time_desc,
 348                           union acpi_operand_object *obj_desc)
 349 {
 350         acpi_status status = AE_OK;
 351
 352         ACPI_FUNCTION_TRACE(ex_system_wait_event);
 353
 354         if (obj_desc) {
 355                 status =
 356                     acpi_ex_system_wait_semaphore(obj_desc->event.os_semaphore,
 357                                                   (u16) time_desc->integer.
 358                                                   value);
 359         }
 360
 361         return_ACPI_STATUS(status);
 362 }
 363
 364 /*******************************************************************************
 365  *
 366  * FUNCTION:    acpi_ex_system_reset_event
 367  *
 368  * PARAMETERS:  obj_desc        - The object descriptor for this op
 369  *
 370  * RETURN:      Status
 371  *
 372  * DESCRIPTION: Reset an event to a known state.
 373  *
 374  ******************************************************************************/
 375
 376 acpi_status acpi_ex_system_reset_event(union acpi_operand_object *obj_desc)
 377 {
 378         acpi_status status = AE_OK;
 379         acpi_semaphore temp_semaphore;
 380
 381         ACPI_FUNCTION_ENTRY();
 382
 383         /*
 384          * We are going to simply delete the existing semaphore and
 385          * create a new one!
 386          */
 387         status =
 388             acpi_os_create_semaphore(ACPI_NO_UNIT_LIMIT, 0, &temp_semaphore);
 389         if (ACPI_SUCCESS(status)) {
 390                 (void)acpi_os_delete_semaphore(obj_desc->event.os_semaphore);
 391                 obj_desc->event.os_semaphore = temp_semaphore;
 392         }
 393
 394         return (status);
 395 }