drivers/acpi/acpica/hwsleep.c

   1 // SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
   2 /******************************************************************************
   3  *
   4  * Name: hwsleep.c - ACPI Hardware Sleep/Wake Support functions for the
   5  *                   original/legacy sleep/PM registers.
   6  *
   7  * Copyright (C) 2000 - 2020, Intel Corp.
   8  *
   9  *****************************************************************************/
  10
  11 #include <acpi/acpi.h>
  12 #include "accommon.h"
  13
  14 #define _COMPONENT          ACPI_HARDWARE
  15 ACPI_MODULE_NAME("hwsleep")
  16
  17 #if (!ACPI_REDUCED_HARDWARE)    /* Entire module */
  18 /*******************************************************************************
  19  *
  20  * FUNCTION:    acpi_hw_legacy_sleep
  21  *
  22  * PARAMETERS:  sleep_state         - Which sleep state to enter
  23  *
  24  * RETURN:      Status
  25  *
  26  * DESCRIPTION: Enter a system sleep state via the legacy FADT PM registers
  27  *              THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED
  28  *
  29  ******************************************************************************/
  30 acpi_status acpi_hw_legacy_sleep(u8 sleep_state)
  31 {
  32         struct acpi_bit_register_info *sleep_type_reg_info;
  33         struct acpi_bit_register_info *sleep_enable_reg_info;
  34         u32 pm1a_control;
  35         u32 pm1b_control;
  36         u32 in_value;
  37         acpi_status status;
  38
  39         ACPI_FUNCTION_TRACE(hw_legacy_sleep);
  40
  41         sleep_type_reg_info =
  42             acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE);
  43         sleep_enable_reg_info =
  44             acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);
  45
  46         /* Clear wake status */
  47
  48         status = acpi_write_bit_register(ACPI_BITREG_WAKE_STATUS,
  49                                          ACPI_CLEAR_STATUS);
  50         if (ACPI_FAILURE(status)) {
  51                 return_ACPI_STATUS(status);
  52         }
  53
  54         /* Disable all GPEs */
  55         status = acpi_hw_disable_all_gpes();
  56         if (ACPI_FAILURE(status)) {
  57                 return_ACPI_STATUS(status);
  58         }
  59         status = acpi_hw_clear_acpi_status();
  60         if (ACPI_FAILURE(status)) {
  61                 return_ACPI_STATUS(status);
  62         }
  63         acpi_gbl_system_awake_and_running = FALSE;
  64
  65          /* Enable all wakeup GPEs */
  66         status = acpi_hw_enable_all_wakeup_gpes();
  67         if (ACPI_FAILURE(status)) {
  68                 return_ACPI_STATUS(status);
  69         }
  70
  71         /* Get current value of PM1A control */
  72
  73         status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL,
  74                                        &pm1a_control);
  75         if (ACPI_FAILURE(status)) {
  76                 return_ACPI_STATUS(status);
  77         }
  78         ACPI_DEBUG_PRINT((ACPI_DB_INIT,
  79                           "Entering sleep state [S%u]\n", sleep_state));
  80
  81         /* Clear the SLP_EN and SLP_TYP fields */
  82
  83         pm1a_control &= ~(sleep_type_reg_info->access_bit_mask |
  84                           sleep_enable_reg_info->access_bit_mask);
  85         pm1b_control = pm1a_control;
  86
  87         /* Insert the SLP_TYP bits */
  88
  89         pm1a_control |=
  90             (acpi_gbl_sleep_type_a << sleep_type_reg_info->bit_position);
  91         pm1b_control |=
  92             (acpi_gbl_sleep_type_b << sleep_type_reg_info->bit_position);
  93
  94         /*
  95          * We split the writes of SLP_TYP and SLP_EN to workaround
  96          * poorly implemented hardware.
  97          */
  98
  99         /* Write #1: write the SLP_TYP data to the PM1 Control registers */
 100
 101         status = acpi_hw_write_pm1_control(pm1a_control, pm1b_control);
 102         if (ACPI_FAILURE(status)) {
 103                 return_ACPI_STATUS(status);
 104         }
 105
 106         /* Insert the sleep enable (SLP_EN) bit */
 107
 108         pm1a_control |= sleep_enable_reg_info->access_bit_mask;
 109         pm1b_control |= sleep_enable_reg_info->access_bit_mask;
 110
 111         /* Flush caches, as per ACPI specification */
 112
 113         ACPI_FLUSH_CPU_CACHE();
 114
 115         status = acpi_os_enter_sleep(sleep_state, pm1a_control, pm1b_control);
 116         if (status == AE_CTRL_TERMINATE) {
 117                 return_ACPI_STATUS(AE_OK);
 118         }
 119         if (ACPI_FAILURE(status)) {
 120                 return_ACPI_STATUS(status);
 121         }
 122
 123         /* Write #2: Write both SLP_TYP + SLP_EN */
 124
 125         status = acpi_hw_write_pm1_control(pm1a_control, pm1b_control);
 126         if (ACPI_FAILURE(status)) {
 127                 return_ACPI_STATUS(status);
 128         }
 129
 130         if (sleep_state > ACPI_STATE_S3) {
 131                 /*
 132                  * We wanted to sleep > S3, but it didn't happen (by virtue of the
 133                  * fact that we are still executing!)
 134                  *
 135                  * Wait ten seconds, then try again. This is to get S4/S5 to work on
 136                  * all machines.
 137                  *
 138                  * We wait so long to allow chipsets that poll this reg very slowly
 139                  * to still read the right value. Ideally, this block would go
 140                  * away entirely.
 141                  */
 142                 acpi_os_stall(10 * ACPI_USEC_PER_SEC);
 143
 144                 status = acpi_hw_register_write(ACPI_REGISTER_PM1_CONTROL,
 145                                                 sleep_enable_reg_info->
 146                                                 access_bit_mask);
 147                 if (ACPI_FAILURE(status)) {
 148                         return_ACPI_STATUS(status);
 149                 }
 150         }
 151
 152         /* Wait for transition back to Working State */
 153
 154         do {
 155                 status =
 156                     acpi_read_bit_register(ACPI_BITREG_WAKE_STATUS, &in_value);
 157                 if (ACPI_FAILURE(status)) {
 158                         return_ACPI_STATUS(status);
 159                 }
 160
 161         } while (!in_value);
 162
 163         return_ACPI_STATUS(AE_OK);
 164 }
 165
 166 /*******************************************************************************
 167  *
 168  * FUNCTION:    acpi_hw_legacy_wake_prep
 169  *
 170  * PARAMETERS:  sleep_state         - Which sleep state we just exited
 171  *
 172  * RETURN:      Status
 173  *
 174  * DESCRIPTION: Perform the first state of OS-independent ACPI cleanup after a
 175  *              sleep.
 176  *              Called with interrupts ENABLED.
 177  *
 178  ******************************************************************************/
 179
 180 acpi_status acpi_hw_legacy_wake_prep(u8 sleep_state)
 181 {
 182         acpi_status status;
 183         struct acpi_bit_register_info *sleep_type_reg_info;
 184         struct acpi_bit_register_info *sleep_enable_reg_info;
 185         u32 pm1a_control;
 186         u32 pm1b_control;
 187
 188         ACPI_FUNCTION_TRACE(hw_legacy_wake_prep);
 189
 190         /*
 191          * Set SLP_TYPE and SLP_EN to state S0.
 192          * This is unclear from the ACPI Spec, but it is required
 193          * by some machines.
 194          */
 195         status = acpi_get_sleep_type_data(ACPI_STATE_S0,
 196                                           &acpi_gbl_sleep_type_a,
 197                                           &acpi_gbl_sleep_type_b);
 198         if (ACPI_SUCCESS(status)) {
 199                 sleep_type_reg_info =
 200                     acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE);
 201                 sleep_enable_reg_info =
 202                     acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);
 203
 204                 /* Get current value of PM1A control */
 205
 206                 status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL,
 207                                                &pm1a_control);
 208                 if (ACPI_SUCCESS(status)) {
 209
 210                         /* Clear the SLP_EN and SLP_TYP fields */
 211
 212                         pm1a_control &= ~(sleep_type_reg_info->access_bit_mask |
 213                                           sleep_enable_reg_info->
 214                                           access_bit_mask);
 215                         pm1b_control = pm1a_control;
 216
 217                         /* Insert the SLP_TYP bits */
 218
 219                         pm1a_control |= (acpi_gbl_sleep_type_a <<
 220                                          sleep_type_reg_info->bit_position);
 221                         pm1b_control |= (acpi_gbl_sleep_type_b <<
 222                                          sleep_type_reg_info->bit_position);
 223
 224                         /* Write the control registers and ignore any errors */
 225
 226                         (void)acpi_hw_write_pm1_control(pm1a_control,
 227                                                         pm1b_control);
 228                 }
 229         }
 230
 231         return_ACPI_STATUS(status);
 232 }
 233
 234 /*******************************************************************************
 235  *
 236  * FUNCTION:    acpi_hw_legacy_wake
 237  *
 238  * PARAMETERS:  sleep_state         - Which sleep state we just exited
 239  *
 240  * RETURN:      Status
 241  *
 242  * DESCRIPTION: Perform OS-independent ACPI cleanup after a sleep
 243  *              Called with interrupts ENABLED.
 244  *
 245  ******************************************************************************/
 246
 247 acpi_status acpi_hw_legacy_wake(u8 sleep_state)
 248 {
 249         acpi_status status;
 250
 251         ACPI_FUNCTION_TRACE(hw_legacy_wake);
 252
 253         /* Ensure enter_sleep_state_prep -> enter_sleep_state ordering */
 254
 255         acpi_gbl_sleep_type_a = ACPI_SLEEP_TYPE_INVALID;
 256         acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST, ACPI_SST_WAKING);
 257
 258         /*
 259          * GPEs must be enabled before _WAK is called as GPEs
 260          * might get fired there
 261          *
 262          * Restore the GPEs:
 263          * 1) Disable all GPEs
 264          * 2) Enable all runtime GPEs
 265          */
 266         status = acpi_hw_disable_all_gpes();
 267         if (ACPI_FAILURE(status)) {
 268                 return_ACPI_STATUS(status);
 269         }
 270
 271         status = acpi_hw_enable_all_runtime_gpes();
 272         if (ACPI_FAILURE(status)) {
 273                 return_ACPI_STATUS(status);
 274         }
 275
 276         /*
 277          * Now we can execute _WAK, etc. Some machines require that the GPEs
 278          * are enabled before the wake methods are executed.
 279          */
 280         acpi_hw_execute_sleep_method(METHOD_PATHNAME__WAK, sleep_state);
 281
 282         /*
 283          * Some BIOS code assumes that WAK_STS will be cleared on resume
 284          * and use it to determine whether the system is rebooting or
 285          * resuming. Clear WAK_STS for compatibility.
 286          */
 287         (void)acpi_write_bit_register(ACPI_BITREG_WAKE_STATUS,
 288                                       ACPI_CLEAR_STATUS);
 289         acpi_gbl_system_awake_and_running = TRUE;
 290
 291         /* Enable power button */
 292
 293         (void)
 294             acpi_write_bit_register(acpi_gbl_fixed_event_info
 295                                     [ACPI_EVENT_POWER_BUTTON].
 296                                     enable_register_id, ACPI_ENABLE_EVENT);
 297
 298         (void)
 299             acpi_write_bit_register(acpi_gbl_fixed_event_info
 300                                     [ACPI_EVENT_POWER_BUTTON].
 301                                     status_register_id, ACPI_CLEAR_STATUS);
 302
 303         acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST, ACPI_SST_WORKING);
 304         return_ACPI_STATUS(status);
 305 }
 306
 307 #endif                          /* !ACPI_REDUCED_HARDWARE */