drivers/acpi/acpica/exsystem.c

   1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
   2 /******************************************************************************
   3  *
   4  * Module Name: exsystem - Interface to OS services
   5  *
   6  * Copyright (C) 2000 - 2023, Intel Corp.
   7  *
   8  *****************************************************************************/
   9
  10 #include <acpi/acpi.h>
  11 #include "accommon.h"
  12 #include "acinterp.h"
  13
  14 #define _COMPONENT          ACPI_EXECUTER
  15 ACPI_MODULE_NAME("exsystem")
  16
  17 /*******************************************************************************
  18  *
  19  * FUNCTION:    acpi_ex_system_wait_semaphore
  20  *
  21  * PARAMETERS:  semaphore       - Semaphore to wait on
  22  *              timeout         - Max time to wait
  23  *
  24  * RETURN:      Status
  25  *
  26  * DESCRIPTION: Implements a semaphore wait with a check to see if the
  27  *              semaphore is available immediately. If it is not, the
  28  *              interpreter is released before waiting.
  29  *
  30  ******************************************************************************/
  31 acpi_status acpi_ex_system_wait_semaphore(acpi_semaphore semaphore, u16 timeout)
  32 {
  33         acpi_status status;
  34
  35         ACPI_FUNCTION_TRACE(ex_system_wait_semaphore);
  36
  37         status = acpi_os_wait_semaphore(semaphore, 1, ACPI_DO_NOT_WAIT);
  38         if (ACPI_SUCCESS(status)) {
  39                 return_ACPI_STATUS(status);
  40         }
  41
  42         if (status == AE_TIME) {
  43
  44                 /* We must wait, so unlock the interpreter */
  45
  46                 acpi_ex_exit_interpreter();
  47                 status = acpi_os_wait_semaphore(semaphore, 1, timeout);
  48
  49                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
  50                                   "*** Thread awake after blocking, %s\n",
  51                                   acpi_format_exception(status)));
  52
  53                 /* Reacquire the interpreter */
  54
  55                 acpi_ex_enter_interpreter();
  56         }
  57
  58         return_ACPI_STATUS(status);
  59 }
  60
  61 /*******************************************************************************
  62  *
  63  * FUNCTION:    acpi_ex_system_wait_mutex
  64  *
  65  * PARAMETERS:  mutex           - Mutex to wait on
  66  *              timeout         - Max time to wait
  67  *
  68  * RETURN:      Status
  69  *
  70  * DESCRIPTION: Implements a mutex wait with a check to see if the
  71  *              mutex is available immediately. If it is not, the
  72  *              interpreter is released before waiting.
  73  *
  74  ******************************************************************************/
  75
  76 acpi_status acpi_ex_system_wait_mutex(acpi_mutex mutex, u16 timeout)
  77 {
  78         acpi_status status;
  79
  80         ACPI_FUNCTION_TRACE(ex_system_wait_mutex);
  81
  82         status = acpi_os_acquire_mutex(mutex, ACPI_DO_NOT_WAIT);
  83         if (ACPI_SUCCESS(status)) {
  84                 return_ACPI_STATUS(status);
  85         }
  86
  87         if (status == AE_TIME) {
  88
  89                 /* We must wait, so unlock the interpreter */
  90
  91                 acpi_ex_exit_interpreter();
  92                 status = acpi_os_acquire_mutex(mutex, timeout);
  93
  94                 ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
  95                                   "*** Thread awake after blocking, %s\n",
  96                                   acpi_format_exception(status)));
  97
  98                 /* Reacquire the interpreter */
  99
 100                 acpi_ex_enter_interpreter();
 101         }
 102
 103         return_ACPI_STATUS(status);
 104 }
 105
 106 /*******************************************************************************
 107  *
 108  * FUNCTION:    acpi_ex_system_do_stall
 109  *
 110  * PARAMETERS:  how_long_us     - The amount of time to stall,
 111  *                                in microseconds
 112  *
 113  * RETURN:      Status
 114  *
 115  * DESCRIPTION: Suspend running thread for specified amount of time.
 116  *              Note: ACPI specification requires that Stall() does not
 117  *              relinquish the processor, and delays longer than 100 usec
 118  *              should use Sleep() instead. We allow stalls up to 255 usec
 119  *              for compatibility with other interpreters and existing BIOSs.
 120  *
 121  ******************************************************************************/
 122
 123 acpi_status acpi_ex_system_do_stall(u32 how_long_us)
 124 {
 125         acpi_status status = AE_OK;
 126
 127         ACPI_FUNCTION_ENTRY();
 128
 129         if (how_long_us > 255) {
 130                 /*
 131                  * Longer than 255 microseconds, this is an error
 132                  *
 133                  * (ACPI specifies 100 usec as max, but this gives some slack in
 134                  * order to support existing BIOSs)
 135                  */
 136                 ACPI_ERROR((AE_INFO,
 137                             "Time parameter is too large (%u)", how_long_us));
 138                 status = AE_AML_OPERAND_VALUE;
 139         } else {
 140                 if (how_long_us > 100) {
 141                         ACPI_WARNING((AE_INFO,
 142                                       "Time parameter %u us > 100 us violating ACPI spec, please fix the firmware.",
 143                                       how_long_us));
 144                 }
 145                 acpi_os_stall(how_long_us);
 146         }
 147
 148         return (status);
 149 }
 150
 151 /*******************************************************************************
 152  *
 153  * FUNCTION:    acpi_ex_system_do_sleep
 154  *
 155  * PARAMETERS:  how_long_ms     - The amount of time to sleep,
 156  *                                in milliseconds
 157  *
 158  * RETURN:      None
 159  *
 160  * DESCRIPTION: Sleep the running thread for specified amount of time.
 161  *
 162  ******************************************************************************/
 163
 164 acpi_status acpi_ex_system_do_sleep(u64 how_long_ms)
 165 {
 166         ACPI_FUNCTION_ENTRY();
 167
 168         /* Since this thread will sleep, we must release the interpreter */
 169
 170         acpi_ex_exit_interpreter();
 171
 172         /*
 173          * For compatibility with other ACPI implementations and to prevent
 174          * accidental deep sleeps, limit the sleep time to something reasonable.
 175          */
 176         if (how_long_ms > ACPI_MAX_SLEEP) {
 177                 how_long_ms = ACPI_MAX_SLEEP;
 178         }
 179
 180         acpi_os_sleep(how_long_ms);
 181
 182         /* And now we must get the interpreter again */
 183
 184         acpi_ex_enter_interpreter();
 185         return (AE_OK);
 186 }
 187
 188 /*******************************************************************************
 189  *
 190  * FUNCTION:    acpi_ex_system_signal_event
 191  *
 192  * PARAMETERS:  obj_desc        - The object descriptor for this op
 193  *
 194  * RETURN:      Status
 195  *
 196  * DESCRIPTION: Provides an access point to perform synchronization operations
 197  *              within the AML.
 198  *
 199  ******************************************************************************/
 200
 201 acpi_status acpi_ex_system_signal_event(union acpi_operand_object * obj_desc)
 202 {
 203         acpi_status status = AE_OK;
 204
 205         ACPI_FUNCTION_TRACE(ex_system_signal_event);
 206
 207         if (obj_desc) {
 208                 status =
 209                     acpi_os_signal_semaphore(obj_desc->event.os_semaphore, 1);
 210         }
 211
 212         return_ACPI_STATUS(status);
 213 }
 214
 215 /*******************************************************************************
 216  *
 217  * FUNCTION:    acpi_ex_system_wait_event
 218  *
 219  * PARAMETERS:  time_desc       - The 'time to delay' object descriptor
 220  *              obj_desc        - The object descriptor for this op
 221  *
 222  * RETURN:      Status
 223  *
 224  * DESCRIPTION: Provides an access point to perform synchronization operations
 225  *              within the AML. This operation is a request to wait for an
 226  *              event.
 227  *
 228  ******************************************************************************/
 229
 230 acpi_status
 231 acpi_ex_system_wait_event(union acpi_operand_object *time_desc,
 232                           union acpi_operand_object *obj_desc)
 233 {
 234         acpi_status status = AE_OK;
 235
 236         ACPI_FUNCTION_TRACE(ex_system_wait_event);
 237
 238         if (obj_desc) {
 239                 status =
 240                     acpi_ex_system_wait_semaphore(obj_desc->event.os_semaphore,
 241                                                   (u16) time_desc->integer.
 242                                                   value);
 243         }
 244
 245         return_ACPI_STATUS(status);
 246 }
 247
 248 /*******************************************************************************
 249  *
 250  * FUNCTION:    acpi_ex_system_reset_event
 251  *
 252  * PARAMETERS:  obj_desc        - The object descriptor for this op
 253  *
 254  * RETURN:      Status
 255  *
 256  * DESCRIPTION: Reset an event to a known state.
 257  *
 258  ******************************************************************************/
 259
 260 acpi_status acpi_ex_system_reset_event(union acpi_operand_object *obj_desc)
 261 {
 262         acpi_status status = AE_OK;
 263         acpi_semaphore temp_semaphore;
 264
 265         ACPI_FUNCTION_ENTRY();
 266
 267         /*
 268          * We are going to simply delete the existing semaphore and
 269          * create a new one!
 270          */
 271         status =
 272             acpi_os_create_semaphore(ACPI_NO_UNIT_LIMIT, 0, &temp_semaphore);
 273         if (ACPI_SUCCESS(status)) {
 274                 (void)acpi_os_delete_semaphore(obj_desc->event.os_semaphore);
 275                 obj_desc->event.os_semaphore = temp_semaphore;
 276         }
 277
 278         return (status);
 279 }