drivers/acpi/executer/exsystem.c

   1
   2 /******************************************************************************
   3  *
   4  * Module Name: exsystem - Interface to OS services
   5  *
   6  *****************************************************************************/
   7
   8 /*
   9  * Copyright (C) 2000 - 2007, 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 before waiting.
  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 mutex wait with a check to see if the
 114  *              mutex is available immediately.  If it is not, the
 115  *              interpreter is released before waiting.
 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_signal_event
 231  *
 232  * PARAMETERS:  obj_desc        - The object descriptor for this op
 233  *
 234  * RETURN:      Status
 235  *
 236  * DESCRIPTION: Provides an access point to perform synchronization operations
 237  *              within the AML.
 238  *
 239  ******************************************************************************/
 240
 241 acpi_status acpi_ex_system_signal_event(union acpi_operand_object * obj_desc)
 242 {
 243         acpi_status status = AE_OK;
 244
 245         ACPI_FUNCTION_TRACE(ex_system_signal_event);
 246
 247         if (obj_desc) {
 248                 status =
 249                     acpi_os_signal_semaphore(obj_desc->event.os_semaphore, 1);
 250         }
 251
 252         return_ACPI_STATUS(status);
 253 }
 254
 255 /*******************************************************************************
 256  *
 257  * FUNCTION:    acpi_ex_system_wait_event
 258  *
 259  * PARAMETERS:  time_desc       - The 'time to delay' object descriptor
 260  *              obj_desc        - The object descriptor for this op
 261  *
 262  * RETURN:      Status
 263  *
 264  * DESCRIPTION: Provides an access point to perform synchronization operations
 265  *              within the AML.  This operation is a request to wait for an
 266  *              event.
 267  *
 268  ******************************************************************************/
 269
 270 acpi_status
 271 acpi_ex_system_wait_event(union acpi_operand_object *time_desc,
 272                           union acpi_operand_object *obj_desc)
 273 {
 274         acpi_status status = AE_OK;
 275
 276         ACPI_FUNCTION_TRACE(ex_system_wait_event);
 277
 278         if (obj_desc) {
 279                 status =
 280                     acpi_ex_system_wait_semaphore(obj_desc->event.os_semaphore,
 281                                                   (u16) time_desc->integer.
 282                                                   value);
 283         }
 284
 285         return_ACPI_STATUS(status);
 286 }
 287
 288 /*******************************************************************************
 289  *
 290  * FUNCTION:    acpi_ex_system_reset_event
 291  *
 292  * PARAMETERS:  obj_desc        - The object descriptor for this op
 293  *
 294  * RETURN:      Status
 295  *
 296  * DESCRIPTION: Reset an event to a known state.
 297  *
 298  ******************************************************************************/
 299
 300 acpi_status acpi_ex_system_reset_event(union acpi_operand_object *obj_desc)
 301 {
 302         acpi_status status = AE_OK;
 303         acpi_semaphore temp_semaphore;
 304
 305         ACPI_FUNCTION_ENTRY();
 306
 307         /*
 308          * We are going to simply delete the existing semaphore and
 309          * create a new one!
 310          */
 311         status =
 312             acpi_os_create_semaphore(ACPI_NO_UNIT_LIMIT, 0, &temp_semaphore);
 313         if (ACPI_SUCCESS(status)) {
 314                 (void)acpi_os_delete_semaphore(obj_desc->event.os_semaphore);
 315                 obj_desc->event.os_semaphore = temp_semaphore;
 316         }
 317
 318         return (status);
 319 }