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 - 2018, 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         if (sleep_state < ACPI_STATE_S4) {
 114                 ACPI_FLUSH_CPU_CACHE();
 115         }
 116
 117         status = acpi_os_enter_sleep(sleep_state, pm1a_control, pm1b_control);
 118         if (status == AE_CTRL_TERMINATE) {
 119                 return_ACPI_STATUS(AE_OK);
 120         }
 121         if (ACPI_FAILURE(status)) {
 122                 return_ACPI_STATUS(status);
 123         }
 124
 125         /* Write #2: Write both SLP_TYP + SLP_EN */
 126
 127         status = acpi_hw_write_pm1_control(pm1a_control, pm1b_control);
 128         if (ACPI_FAILURE(status)) {
 129                 return_ACPI_STATUS(status);
 130         }
 131
 132         if (sleep_state > ACPI_STATE_S3) {
 133                 /*
 134                  * We wanted to sleep > S3, but it didn't happen (by virtue of the
 135                  * fact that we are still executing!)
 136                  *
 137                  * Wait ten seconds, then try again. This is to get S4/S5 to work on
 138                  * all machines.
 139                  *
 140                  * We wait so long to allow chipsets that poll this reg very slowly
 141                  * to still read the right value. Ideally, this block would go
 142                  * away entirely.
 143                  */
 144                 acpi_os_stall(10 * ACPI_USEC_PER_SEC);
 145
 146                 status = acpi_hw_register_write(ACPI_REGISTER_PM1_CONTROL,
 147                                                 sleep_enable_reg_info->
 148                                                 access_bit_mask);
 149                 if (ACPI_FAILURE(status)) {
 150                         return_ACPI_STATUS(status);
 151                 }
 152         }
 153
 154         /* Wait for transition back to Working State */
 155
 156         do {
 157                 status =
 158                     acpi_read_bit_register(ACPI_BITREG_WAKE_STATUS, &in_value);
 159                 if (ACPI_FAILURE(status)) {
 160                         return_ACPI_STATUS(status);
 161                 }
 162
 163         } while (!in_value);
 164
 165         return_ACPI_STATUS(AE_OK);
 166 }
 167
 168 /*******************************************************************************
 169  *
 170  * FUNCTION:    acpi_hw_legacy_wake_prep
 171  *
 172  * PARAMETERS:  sleep_state         - Which sleep state we just exited
 173  *
 174  * RETURN:      Status
 175  *
 176  * DESCRIPTION: Perform the first state of OS-independent ACPI cleanup after a
 177  *              sleep.
 178  *              Called with interrupts ENABLED.
 179  *
 180  ******************************************************************************/
 181
 182 acpi_status acpi_hw_legacy_wake_prep(u8 sleep_state)
 183 {
 184         acpi_status status = AE_OK;
 185         struct acpi_bit_register_info *sleep_type_reg_info;
 186         struct acpi_bit_register_info *sleep_enable_reg_info;
 187         u32 pm1a_control;
 188         u32 pm1b_control;
 189
 190         ACPI_FUNCTION_TRACE(hw_legacy_wake_prep);
 191
 192         /*
 193          * Set SLP_TYPE and SLP_EN to state S0.
 194          * This is unclear from the ACPI Spec, but it is required
 195          * by some machines.
 196          */
 197         if (acpi_gbl_sleep_type_a_s0 != ACPI_SLEEP_TYPE_INVALID) {
 198                 sleep_type_reg_info =
 199                     acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE);
 200                 sleep_enable_reg_info =
 201                     acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);
 202
 203                 /* Get current value of PM1A control */
 204
 205                 status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL,
 206                                                &pm1a_control);
 207                 if (ACPI_SUCCESS(status)) {
 208
 209                         /* Clear the SLP_EN and SLP_TYP fields */
 210
 211                         pm1a_control &= ~(sleep_type_reg_info->access_bit_mask |
 212                                           sleep_enable_reg_info->
 213                                           access_bit_mask);
 214                         pm1b_control = pm1a_control;
 215
 216                         /* Insert the SLP_TYP bits */
 217
 218                         pm1a_control |= (acpi_gbl_sleep_type_a_s0 <<
 219                                          sleep_type_reg_info->bit_position);
 220                         pm1b_control |= (acpi_gbl_sleep_type_b_s0 <<
 221                                          sleep_type_reg_info->bit_position);
 222
 223                         /* Write the control registers and ignore any errors */
 224
 225                         (void)acpi_hw_write_pm1_control(pm1a_control,
 226                                                         pm1b_control);
 227                 }
 228         }
 229
 230         return_ACPI_STATUS(status);
 231 }
 232
 233 /*******************************************************************************
 234  *
 235  * FUNCTION:    acpi_hw_legacy_wake
 236  *
 237  * PARAMETERS:  sleep_state         - Which sleep state we just exited
 238  *
 239  * RETURN:      Status
 240  *
 241  * DESCRIPTION: Perform OS-independent ACPI cleanup after a sleep
 242  *              Called with interrupts ENABLED.
 243  *
 244  ******************************************************************************/
 245
 246 acpi_status acpi_hw_legacy_wake(u8 sleep_state)
 247 {
 248         acpi_status status;
 249
 250         ACPI_FUNCTION_TRACE(hw_legacy_wake);
 251
 252         /* Ensure enter_sleep_state_prep -> enter_sleep_state ordering */
 253
 254         acpi_gbl_sleep_type_a = ACPI_SLEEP_TYPE_INVALID;
 255         acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST, ACPI_SST_WAKING);
 256
 257         /*
 258          * GPEs must be enabled before _WAK is called as GPEs
 259          * might get fired there
 260          *
 261          * Restore the GPEs:
 262          * 1) Disable all GPEs
 263          * 2) Enable all runtime GPEs
 264          */
 265         status = acpi_hw_disable_all_gpes();
 266         if (ACPI_FAILURE(status)) {
 267                 return_ACPI_STATUS(status);
 268         }
 269
 270         status = acpi_hw_enable_all_runtime_gpes();
 271         if (ACPI_FAILURE(status)) {
 272                 return_ACPI_STATUS(status);
 273         }
 274
 275         /*
 276          * Now we can execute _WAK, etc. Some machines require that the GPEs
 277          * are enabled before the wake methods are executed.
 278          */
 279         acpi_hw_execute_sleep_method(METHOD_PATHNAME__WAK, sleep_state);
 280
 281         /*
 282          * Some BIOS code assumes that WAK_STS will be cleared on resume
 283          * and use it to determine whether the system is rebooting or
 284          * resuming. Clear WAK_STS for compatibility.
 285          */
 286         (void)acpi_write_bit_register(ACPI_BITREG_WAKE_STATUS,
 287                                       ACPI_CLEAR_STATUS);
 288         acpi_gbl_system_awake_and_running = TRUE;
 289
 290         /* Enable power button */
 291
 292         (void)
 293             acpi_write_bit_register(acpi_gbl_fixed_event_info
 294                                     [ACPI_EVENT_POWER_BUTTON].
 295                                     enable_register_id, ACPI_ENABLE_EVENT);
 296
 297         (void)
 298             acpi_write_bit_register(acpi_gbl_fixed_event_info
 299                                     [ACPI_EVENT_POWER_BUTTON].
 300                                     status_register_id, ACPI_CLEAR_STATUS);
 301
 302         acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST, ACPI_SST_WORKING);
 303         return_ACPI_STATUS(status);
 304 }
 305
 306 #endif                          /* !ACPI_REDUCED_HARDWARE */