drivers/acpi/executer/exsystem.c

   1
   2 /******************************************************************************
   3  *
   4  * Module Name: exsystem - Interface to OS services
   5  *
   6  *****************************************************************************/
   7
   8 /*
   9  * Copyright (C) 2000 - 2005, 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
  46 #include <acpi/acpi.h>
  47 #include <acpi/acinterp.h>
  48 #include <acpi/acevents.h>
  49
  50 #define _COMPONENT          ACPI_EXECUTER
  51          ACPI_MODULE_NAME    ("exsystem")
  52
  53
  54 /*******************************************************************************
  55  *
  56  * FUNCTION:    acpi_ex_system_wait_semaphore
  57  *
  58  * PARAMETERS:  Semaphore           - OSD semaphore to wait on
  59  *              Timeout             - Max time to wait
  60  *
  61  * RETURN:      Status
  62  *
  63  * DESCRIPTION: Implements a semaphore wait with a check to see if the
  64  *              semaphore is available immediately.  If it is not, the
  65  *              interpreter is released.
  66  *
  67  ******************************************************************************/
  68
  69 acpi_status
  70 acpi_ex_system_wait_semaphore (
  71         acpi_handle                     semaphore,
  72         u16                             timeout)
  73 {
  74         acpi_status                     status;
  75         acpi_status                     status2;
  76
  77
  78         ACPI_FUNCTION_TRACE ("ex_system_wait_semaphore");
  79
  80
  81         status = acpi_os_wait_semaphore (semaphore, 1, 0);
  82         if (ACPI_SUCCESS (status)) {
  83                 return_ACPI_STATUS (status);
  84         }
  85
  86         if (status == AE_TIME) {
  87                 /* We must wait, so unlock the interpreter */
  88
  89                 acpi_ex_exit_interpreter ();
  90
  91                 status = acpi_os_wait_semaphore (semaphore, 1, timeout);
  92
  93                 ACPI_DEBUG_PRINT ((ACPI_DB_EXEC, "*** Thread awake after blocking, %s\n",
  94                         acpi_format_exception (status)));
  95
  96                 /* Reacquire the interpreter */
  97
  98                 status2 = acpi_ex_enter_interpreter ();
  99                 if (ACPI_FAILURE (status2)) {
 100                         /* Report fatal error, could not acquire interpreter */
 101
 102                         return_ACPI_STATUS (status2);
 103                 }
 104         }
 105
 106         return_ACPI_STATUS (status);
 107 }
 108
 109
 110 /*******************************************************************************
 111  *
 112  * FUNCTION:    acpi_ex_system_do_stall
 113  *
 114  * PARAMETERS:  how_long            - The amount of time to stall,
 115  *                                    in microseconds
 116  *
 117  * RETURN:      Status
 118  *
 119  * DESCRIPTION: Suspend running thread for specified amount of time.
 120  *              Note: ACPI specification requires that Stall() does not
 121  *              relinquish the processor, and delays longer than 100 usec
 122  *              should use Sleep() instead.  We allow stalls up to 255 usec
 123  *              for compatibility with other interpreters and existing BIOSs.
 124  *
 125  ******************************************************************************/
 126
 127 acpi_status
 128 acpi_ex_system_do_stall (
 129         u32                             how_long)
 130 {
 131         acpi_status                     status = AE_OK;
 132
 133
 134         ACPI_FUNCTION_ENTRY ();
 135
 136
 137         if (how_long > 255) /* 255 microseconds */ {
 138                 /*
 139                  * Longer than 255 usec, this is an error
 140                  *
 141                  * (ACPI specifies 100 usec as max, but this gives some slack in
 142                  * order to support existing BIOSs)
 143                  */
 144                 ACPI_REPORT_ERROR (("Stall: Time parameter is too large (%d)\n", how_long));
 145                 status = AE_AML_OPERAND_VALUE;
 146         }
 147         else {
 148                 acpi_os_stall (how_long);
 149         }
 150
 151         return (status);
 152 }
 153
 154
 155 /*******************************************************************************
 156  *
 157  * FUNCTION:    acpi_ex_system_do_suspend
 158  *
 159  * PARAMETERS:  how_long            - The amount of time to suspend,
 160  *                                    in milliseconds
 161  *
 162  * RETURN:      None
 163  *
 164  * DESCRIPTION: Suspend running thread for specified amount of time.
 165  *
 166  ******************************************************************************/
 167
 168 acpi_status
 169 acpi_ex_system_do_suspend (
 170         acpi_integer                    how_long)
 171 {
 172         acpi_status                     status;
 173
 174
 175         ACPI_FUNCTION_ENTRY ();
 176
 177
 178         /* Since this thread will sleep, we must release the interpreter */
 179
 180         acpi_ex_exit_interpreter ();
 181
 182         acpi_os_sleep (how_long);
 183
 184         /* And now we must get the interpreter again */
 185
 186         status = acpi_ex_enter_interpreter ();
 187         return (status);
 188 }
 189
 190
 191 /*******************************************************************************
 192  *
 193  * FUNCTION:    acpi_ex_system_acquire_mutex
 194  *
 195  * PARAMETERS:  *time_desc          - The 'time to delay' object descriptor
 196  *              *obj_desc           - The object descriptor for this op
 197  *
 198  * RETURN:      Status
 199  *
 200  * DESCRIPTION: Provides an access point to perform synchronization operations
 201  *              within the AML.  This function will cause a lock to be generated
 202  *              for the Mutex pointed to by obj_desc.
 203  *
 204  ******************************************************************************/
 205
 206 acpi_status
 207 acpi_ex_system_acquire_mutex (
 208         union acpi_operand_object       *time_desc,
 209         union acpi_operand_object       *obj_desc)
 210 {
 211         acpi_status                     status = AE_OK;
 212
 213
 214         ACPI_FUNCTION_TRACE_PTR ("ex_system_acquire_mutex", obj_desc);
 215
 216
 217         if (!obj_desc) {
 218                 return_ACPI_STATUS (AE_BAD_PARAMETER);
 219         }
 220
 221         /*
 222          * Support for the _GL_ Mutex object -- go get the global lock
 223          */
 224         if (obj_desc->mutex.semaphore == acpi_gbl_global_lock_semaphore) {
 225                 status = acpi_ev_acquire_global_lock ((u16) time_desc->integer.value);
 226                 return_ACPI_STATUS (status);
 227         }
 228
 229         status = acpi_ex_system_wait_semaphore (obj_desc->mutex.semaphore,
 230                           (u16) time_desc->integer.value);
 231         return_ACPI_STATUS (status);
 232 }
 233
 234
 235 /*******************************************************************************
 236  *
 237  * FUNCTION:    acpi_ex_system_release_mutex
 238  *
 239  * PARAMETERS:  *obj_desc           - The object descriptor for this op
 240  *
 241  * RETURN:      Status
 242  *
 243  * DESCRIPTION: Provides an access point to perform synchronization operations
 244  *              within the AML.  This operation is a request to release a
 245  *              previously acquired Mutex.  If the Mutex variable is set then
 246  *              it will be decremented.
 247  *
 248  ******************************************************************************/
 249
 250 acpi_status
 251 acpi_ex_system_release_mutex (
 252         union acpi_operand_object       *obj_desc)
 253 {
 254         acpi_status                     status = AE_OK;
 255
 256
 257         ACPI_FUNCTION_TRACE ("ex_system_release_mutex");
 258
 259
 260         if (!obj_desc) {
 261                 return_ACPI_STATUS (AE_BAD_PARAMETER);
 262         }
 263
 264         /*
 265          * Support for the _GL_ Mutex object -- release the global lock
 266          */
 267         if (obj_desc->mutex.semaphore == acpi_gbl_global_lock_semaphore) {
 268                 status = acpi_ev_release_global_lock ();
 269                 return_ACPI_STATUS (status);
 270         }
 271
 272         status = acpi_os_signal_semaphore (obj_desc->mutex.semaphore, 1);
 273         return_ACPI_STATUS (status);
 274 }
 275
 276
 277 /*******************************************************************************
 278  *
 279  * FUNCTION:    acpi_ex_system_signal_event
 280  *
 281  * PARAMETERS:  *obj_desc           - The object descriptor for this op
 282  *
 283  * RETURN:      AE_OK
 284  *
 285  * DESCRIPTION: Provides an access point to perform synchronization operations
 286  *              within the AML.
 287  *
 288  ******************************************************************************/
 289
 290 acpi_status
 291 acpi_ex_system_signal_event (
 292         union acpi_operand_object       *obj_desc)
 293 {
 294         acpi_status                     status = AE_OK;
 295
 296
 297         ACPI_FUNCTION_TRACE ("ex_system_signal_event");
 298
 299
 300         if (obj_desc) {
 301                 status = acpi_os_signal_semaphore (obj_desc->event.semaphore, 1);
 302         }
 303
 304         return_ACPI_STATUS (status);
 305 }
 306
 307
 308 /*******************************************************************************
 309  *
 310  * FUNCTION:    acpi_ex_system_wait_event
 311  *
 312  * PARAMETERS:  *time_desc          - The 'time to delay' object descriptor
 313  *              *obj_desc           - The object descriptor for this op
 314  *
 315  * RETURN:      Status
 316  *
 317  * DESCRIPTION: Provides an access point to perform synchronization operations
 318  *              within the AML.  This operation is a request to wait for an
 319  *              event.
 320  *
 321  ******************************************************************************/
 322
 323 acpi_status
 324 acpi_ex_system_wait_event (
 325         union acpi_operand_object       *time_desc,
 326         union acpi_operand_object       *obj_desc)
 327 {
 328         acpi_status                     status = AE_OK;
 329
 330
 331         ACPI_FUNCTION_TRACE ("ex_system_wait_event");
 332
 333
 334         if (obj_desc) {
 335                 status = acpi_ex_system_wait_semaphore (obj_desc->event.semaphore,
 336                                   (u16) time_desc->integer.value);
 337         }
 338
 339         return_ACPI_STATUS (status);
 340 }
 341
 342
 343 /*******************************************************************************
 344  *
 345  * FUNCTION:    acpi_ex_system_reset_event
 346  *
 347  * PARAMETERS:  *obj_desc           - The object descriptor for this op
 348  *
 349  * RETURN:      Status
 350  *
 351  * DESCRIPTION: Reset an event to a known state.
 352  *
 353  ******************************************************************************/
 354
 355 acpi_status
 356 acpi_ex_system_reset_event (
 357         union acpi_operand_object       *obj_desc)
 358 {
 359         acpi_status                     status = AE_OK;
 360         void                            *temp_semaphore;
 361
 362
 363         ACPI_FUNCTION_ENTRY ();
 364
 365
 366         /*
 367          * We are going to simply delete the existing semaphore and
 368          * create a new one!
 369          */
 370         status = acpi_os_create_semaphore (ACPI_NO_UNIT_LIMIT, 0, &temp_semaphore);
 371         if (ACPI_SUCCESS (status)) {
 372                 (void) acpi_os_delete_semaphore (obj_desc->event.semaphore);
 373                 obj_desc->event.semaphore = temp_semaphore;
 374         }
 375
 376         return (status);
 377 }
 378