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