drivers/acpi/acpica/exsystem.c

   1 /******************************************************************************
   2  *
   3  * Module Name: exsystem - Interface to OS services
   4  *
   5  *****************************************************************************/
   6
   7 /*
   8  * Copyright (C) 2000 - 2016, Intel Corp.
   9  * All rights reserved.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions, and the following disclaimer,
  16  *    without modification.
  17  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  18  *    substantially similar to the "NO WARRANTY" disclaimer below
  19  *    ("Disclaimer") and any redistribution must be conditioned upon
  20  *    including a substantially similar Disclaimer requirement for further
  21  *    binary redistribution.
  22  * 3. Neither the names of the above-listed copyright holders nor the names
  23  *    of any contributors may be used to endorse or promote products derived
  24  *    from this software without specific prior written permission.
  25  *
  26  * Alternatively, this software may be distributed under the terms of the
  27  * GNU General Public License ("GPL") version 2 as published by the Free
  28  * Software Foundation.
  29  *
  30  * NO WARRANTY
  31  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  32  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  33  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  34  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  35  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  39  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  40  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  41  * POSSIBILITY OF SUCH DAMAGES.
  42  */
  43
  44 #include <acpi/acpi.h>
  45 #include "accommon.h"
  46 #include "acinterp.h"
  47
  48 #define _COMPONENT          ACPI_EXECUTER
  49 ACPI_MODULE_NAME("exsystem")
  50
  51 /*******************************************************************************
  52  *
  53  * FUNCTION:    acpi_ex_system_wait_semaphore
  54  *
  55  * PARAMETERS:  semaphore       - Semaphore to wait on
  56  *              timeout         - Max time to wait
  57  *
  58  * RETURN:      Status
  59  *
  60  * DESCRIPTION: Implements a semaphore wait with a check to see if the
  61  *              semaphore is available immediately. If it is not, the
  62  *              interpreter is released before waiting.
  63  *
  64  ******************************************************************************/
  65 acpi_status acpi_ex_system_wait_semaphore(acpi_semaphore semaphore, u16 timeout)
  66 {
  67         acpi_status status;
  68
  69         ACPI_FUNCTION_TRACE(ex_system_wait_semaphore);
  70
  71         status = acpi_os_wait_semaphore(semaphore, 1, ACPI_DO_NOT_WAIT);
  72         if (ACPI_SUCCESS(status)) {
  73                 return_ACPI_STATUS(status);
  74         }
  75
  76         if (status == AE_TIME) {
  77
  78                 /* We must wait, so unlock the interpreter */
  79
  80                 acpi_ex_exit_interpreter();
  81                 status = acpi_os_wait_semaphore(semaphore, 1, timeout);
  82
  83                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
  84                                   "*** Thread awake after blocking, %s\n",
  85                                   acpi_format_exception(status)));
  86
  87                 /* Reacquire the interpreter */
  88
  89                 acpi_ex_enter_interpreter();
  90         }
  91
  92         return_ACPI_STATUS(status);
  93 }
  94
  95 /*******************************************************************************
  96  *
  97  * FUNCTION:    acpi_ex_system_wait_mutex
  98  *
  99  * PARAMETERS:  mutex           - Mutex to wait on
 100  *              timeout         - Max time to wait
 101  *
 102  * RETURN:      Status
 103  *
 104  * DESCRIPTION: Implements a mutex wait with a check to see if the
 105  *              mutex is available immediately. If it is not, the
 106  *              interpreter is released before waiting.
 107  *
 108  ******************************************************************************/
 109
 110 acpi_status acpi_ex_system_wait_mutex(acpi_mutex mutex, u16 timeout)
 111 {
 112         acpi_status status;
 113
 114         ACPI_FUNCTION_TRACE(ex_system_wait_mutex);
 115
 116         status = acpi_os_acquire_mutex(mutex, ACPI_DO_NOT_WAIT);
 117         if (ACPI_SUCCESS(status)) {
 118                 return_ACPI_STATUS(status);
 119         }
 120
 121         if (status == AE_TIME) {
 122
 123                 /* We must wait, so unlock the interpreter */
 124
 125                 acpi_ex_exit_interpreter();
 126                 status = acpi_os_acquire_mutex(mutex, timeout);
 127
 128                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
 129                                   "*** Thread awake after blocking, %s\n",
 130                                   acpi_format_exception(status)));
 131
 132                 /* Reacquire the interpreter */
 133
 134                 acpi_ex_enter_interpreter();
 135         }
 136
 137         return_ACPI_STATUS(status);
 138 }
 139
 140 /*******************************************************************************
 141  *
 142  * FUNCTION:    acpi_ex_system_do_stall
 143  *
 144  * PARAMETERS:  how_long        - The amount of time to stall,
 145  *                                in microseconds
 146  *
 147  * RETURN:      Status
 148  *
 149  * DESCRIPTION: Suspend running thread for specified amount of time.
 150  *              Note: ACPI specification requires that Stall() does not
 151  *              relinquish the processor, and delays longer than 100 usec
 152  *              should use Sleep() instead. We allow stalls up to 255 usec
 153  *              for compatibility with other interpreters and existing BIOSs.
 154  *
 155  ******************************************************************************/
 156
 157 acpi_status acpi_ex_system_do_stall(u32 how_long)
 158 {
 159         acpi_status status = AE_OK;
 160
 161         ACPI_FUNCTION_ENTRY();
 162
 163         if (how_long > 255) {   /* 255 microseconds */
 164                 /*
 165                  * Longer than 255 usec, this is an error
 166                  *
 167                  * (ACPI specifies 100 usec as max, but this gives some slack in
 168                  * order to support existing BIOSs)
 169                  */
 170                 ACPI_ERROR((AE_INFO,
 171                             "Time parameter is too large (%u)", how_long));
 172                 status = AE_AML_OPERAND_VALUE;
 173         } else {
 174                 acpi_os_stall(how_long);
 175         }
 176
 177         return (status);
 178 }
 179
 180 /*******************************************************************************
 181  *
 182  * FUNCTION:    acpi_ex_system_do_sleep
 183  *
 184  * PARAMETERS:  how_long        - The amount of time to sleep,
 185  *                                in milliseconds
 186  *
 187  * RETURN:      None
 188  *
 189  * DESCRIPTION: Sleep the running thread for specified amount of time.
 190  *
 191  ******************************************************************************/
 192
 193 acpi_status acpi_ex_system_do_sleep(u64 how_long)
 194 {
 195         ACPI_FUNCTION_ENTRY();
 196
 197         /* Since this thread will sleep, we must release the interpreter */
 198
 199         acpi_ex_exit_interpreter();
 200
 201         /*
 202          * For compatibility with other ACPI implementations and to prevent
 203          * accidental deep sleeps, limit the sleep time to something reasonable.
 204          */
 205         if (how_long > ACPI_MAX_SLEEP) {
 206                 how_long = ACPI_MAX_SLEEP;
 207         }
 208
 209         acpi_os_sleep(how_long);
 210
 211         /* And now we must get the interpreter again */
 212
 213         acpi_ex_enter_interpreter();
 214         return (AE_OK);
 215 }
 216
 217 /*******************************************************************************
 218  *
 219  * FUNCTION:    acpi_ex_system_signal_event
 220  *
 221  * PARAMETERS:  obj_desc        - The object descriptor for this op
 222  *
 223  * RETURN:      Status
 224  *
 225  * DESCRIPTION: Provides an access point to perform synchronization operations
 226  *              within the AML.
 227  *
 228  ******************************************************************************/
 229
 230 acpi_status acpi_ex_system_signal_event(union acpi_operand_object * obj_desc)
 231 {
 232         acpi_status status = AE_OK;
 233
 234         ACPI_FUNCTION_TRACE(ex_system_signal_event);
 235
 236         if (obj_desc) {
 237                 status =
 238                     acpi_os_signal_semaphore(obj_desc->event.os_semaphore, 1);
 239         }
 240
 241         return_ACPI_STATUS(status);
 242 }
 243
 244 /*******************************************************************************
 245  *
 246  * FUNCTION:    acpi_ex_system_wait_event
 247  *
 248  * PARAMETERS:  time_desc       - The 'time to delay' object descriptor
 249  *              obj_desc        - The object descriptor for this op
 250  *
 251  * RETURN:      Status
 252  *
 253  * DESCRIPTION: Provides an access point to perform synchronization operations
 254  *              within the AML. This operation is a request to wait for an
 255  *              event.
 256  *
 257  ******************************************************************************/
 258
 259 acpi_status
 260 acpi_ex_system_wait_event(union acpi_operand_object *time_desc,
 261                           union acpi_operand_object *obj_desc)
 262 {
 263         acpi_status status = AE_OK;
 264
 265         ACPI_FUNCTION_TRACE(ex_system_wait_event);
 266
 267         if (obj_desc) {
 268                 status =
 269                     acpi_ex_system_wait_semaphore(obj_desc->event.os_semaphore,
 270                                                   (u16) time_desc->integer.
 271                                                   value);
 272         }
 273
 274         return_ACPI_STATUS(status);
 275 }
 276
 277 /*******************************************************************************
 278  *
 279  * FUNCTION:    acpi_ex_system_reset_event
 280  *
 281  * PARAMETERS:  obj_desc        - The object descriptor for this op
 282  *
 283  * RETURN:      Status
 284  *
 285  * DESCRIPTION: Reset an event to a known state.
 286  *
 287  ******************************************************************************/
 288
 289 acpi_status acpi_ex_system_reset_event(union acpi_operand_object *obj_desc)
 290 {
 291         acpi_status status = AE_OK;
 292         acpi_semaphore temp_semaphore;
 293
 294         ACPI_FUNCTION_ENTRY();
 295
 296         /*
 297          * We are going to simply delete the existing semaphore and
 298          * create a new one!
 299          */
 300         status =
 301             acpi_os_create_semaphore(ACPI_NO_UNIT_LIMIT, 0, &temp_semaphore);
 302         if (ACPI_SUCCESS(status)) {
 303                 (void)acpi_os_delete_semaphore(obj_desc->event.os_semaphore);
 304                 obj_desc->event.os_semaphore = temp_semaphore;
 305         }
 306
 307         return (status);
 308 }