drivers/acpi/acpica/hwsleep.c

   1 /******************************************************************************
   2  *
   3  * Name: hwsleep.c - ACPI Hardware Sleep/Wake Support functions for the
   4  *                   original/legacy sleep/PM registers.
   5  *
   6  *****************************************************************************/
   7
   8 /*
   9  * Copyright (C) 2000 - 2012, Intel Corp.
  10  * All rights reserved.
  11  *
  12  * Redistribution and use in source and binary forms, with or without
  13  * modification, are permitted provided that the following conditions
  14  * are met:
  15  * 1. Redistributions of source code must retain the above copyright
  16  *    notice, this list of conditions, and the following disclaimer,
  17  *    without modification.
  18  * 2. Redistributions in binary form must reproduce at minimum a disclaimer
  19  *    substantially similar to the "NO WARRANTY" disclaimer below
  20  *    ("Disclaimer") and any redistribution must be conditioned upon
  21  *    including a substantially similar Disclaimer requirement for further
  22  *    binary redistribution.
  23  * 3. Neither the names of the above-listed copyright holders nor the names
  24  *    of any contributors may be used to endorse or promote products derived
  25  *    from this software without specific prior written permission.
  26  *
  27  * Alternatively, this software may be distributed under the terms of the
  28  * GNU General Public License ("GPL") version 2 as published by the Free
  29  * Software Foundation.
  30  *
  31  * NO WARRANTY
  32  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  33  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  34  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
  35  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  36  * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  37  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  38  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  39  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  40  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  41  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  42  * POSSIBILITY OF SUCH DAMAGES.
  43  */
  44
  45 #include <acpi/acpi.h>
  46 #include <linux/acpi.h>
  47 #include "accommon.h"
  48 #include <linux/module.h>
  49
  50 #define _COMPONENT          ACPI_HARDWARE
  51 ACPI_MODULE_NAME("hwsleep")
  52
  53 #if (!ACPI_REDUCED_HARDWARE)    /* Entire module */
  54 /*******************************************************************************
  55  *
  56  * FUNCTION:    acpi_hw_legacy_sleep
  57  *
  58  * PARAMETERS:  sleep_state         - Which sleep state to enter
  59  *
  60  * RETURN:      Status
  61  *
  62  * DESCRIPTION: Enter a system sleep state via the legacy FADT PM registers
  63  *              THIS FUNCTION MUST BE CALLED WITH INTERRUPTS DISABLED
  64  *
  65  ******************************************************************************/
  66 acpi_status acpi_hw_legacy_sleep(u8 sleep_state)
  67 {
  68         struct acpi_bit_register_info *sleep_type_reg_info;
  69         struct acpi_bit_register_info *sleep_enable_reg_info;
  70         u32 pm1a_control;
  71         u32 pm1b_control;
  72         u32 in_value;
  73         acpi_status status;
  74
  75         ACPI_FUNCTION_TRACE(hw_legacy_sleep);
  76
  77         sleep_type_reg_info =
  78             acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE);
  79         sleep_enable_reg_info =
  80             acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);
  81
  82         /* Clear wake status */
  83
  84         status =
  85             acpi_write_bit_register(ACPI_BITREG_WAKE_STATUS, ACPI_CLEAR_STATUS);
  86         if (ACPI_FAILURE(status)) {
  87                 return_ACPI_STATUS(status);
  88         }
  89
  90         /* Clear all fixed and general purpose status bits */
  91
  92         status = acpi_hw_clear_acpi_status();
  93         if (ACPI_FAILURE(status)) {
  94                 return_ACPI_STATUS(status);
  95         }
  96
  97         /*
  98          * 1) Disable/Clear all GPEs
  99          * 2) Enable all wakeup GPEs
 100          */
 101         status = acpi_hw_disable_all_gpes();
 102         if (ACPI_FAILURE(status)) {
 103                 return_ACPI_STATUS(status);
 104         }
 105         acpi_gbl_system_awake_and_running = FALSE;
 106
 107         status = acpi_hw_enable_all_wakeup_gpes();
 108         if (ACPI_FAILURE(status)) {
 109                 return_ACPI_STATUS(status);
 110         }
 111
 112         /* Get current value of PM1A control */
 113
 114         status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL,
 115                                        &pm1a_control);
 116         if (ACPI_FAILURE(status)) {
 117                 return_ACPI_STATUS(status);
 118         }
 119         ACPI_DEBUG_PRINT((ACPI_DB_INIT,
 120                           "Entering sleep state [S%u]\n", sleep_state));
 121
 122         /* Clear the SLP_EN and SLP_TYP fields */
 123
 124         pm1a_control &= ~(sleep_type_reg_info->access_bit_mask |
 125                           sleep_enable_reg_info->access_bit_mask);
 126         pm1b_control = pm1a_control;
 127
 128         /* Insert the SLP_TYP bits */
 129
 130         pm1a_control |=
 131             (acpi_gbl_sleep_type_a << sleep_type_reg_info->bit_position);
 132         pm1b_control |=
 133             (acpi_gbl_sleep_type_b << sleep_type_reg_info->bit_position);
 134
 135         /*
 136          * We split the writes of SLP_TYP and SLP_EN to workaround
 137          * poorly implemented hardware.
 138          */
 139
 140         /* Write #1: write the SLP_TYP data to the PM1 Control registers */
 141
 142         status = acpi_hw_write_pm1_control(pm1a_control, pm1b_control);
 143         if (ACPI_FAILURE(status)) {
 144                 return_ACPI_STATUS(status);
 145         }
 146
 147         /* Insert the sleep enable (SLP_EN) bit */
 148
 149         pm1a_control |= sleep_enable_reg_info->access_bit_mask;
 150         pm1b_control |= sleep_enable_reg_info->access_bit_mask;
 151
 152         /* Flush caches, as per ACPI specification */
 153
 154         ACPI_FLUSH_CPU_CACHE();
 155
 156         status = acpi_os_prepare_sleep(sleep_state, pm1a_control,
 157                                        pm1b_control);
 158         if (ACPI_SKIP(status))
 159                 return_ACPI_STATUS(AE_OK);
 160         if (ACPI_FAILURE(status))
 161                 return_ACPI_STATUS(status);
 162         /* Write #2: Write both SLP_TYP + SLP_EN */
 163
 164         status = acpi_hw_write_pm1_control(pm1a_control, pm1b_control);
 165         if (ACPI_FAILURE(status)) {
 166                 return_ACPI_STATUS(status);
 167         }
 168
 169         if (sleep_state > ACPI_STATE_S3) {
 170                 /*
 171                  * We wanted to sleep > S3, but it didn't happen (by virtue of the
 172                  * fact that we are still executing!)
 173                  *
 174                  * Wait ten seconds, then try again. This is to get S4/S5 to work on
 175                  * all machines.
 176                  *
 177                  * We wait so long to allow chipsets that poll this reg very slowly
 178                  * to still read the right value. Ideally, this block would go
 179                  * away entirely.
 180                  */
 181                 acpi_os_stall(10000000);
 182
 183                 status = acpi_hw_register_write(ACPI_REGISTER_PM1_CONTROL,
 184                                                 sleep_enable_reg_info->
 185                                                 access_bit_mask);
 186                 if (ACPI_FAILURE(status)) {
 187                         return_ACPI_STATUS(status);
 188                 }
 189         }
 190
 191         /* Wait for transition back to Working State */
 192
 193         do {
 194                 status =
 195                     acpi_read_bit_register(ACPI_BITREG_WAKE_STATUS, &in_value);
 196                 if (ACPI_FAILURE(status)) {
 197                         return_ACPI_STATUS(status);
 198                 }
 199
 200         } while (!in_value);
 201
 202         return_ACPI_STATUS(AE_OK);
 203 }
 204
 205 /*******************************************************************************
 206  *
 207  * FUNCTION:    acpi_hw_legacy_wake_prep
 208  *
 209  * PARAMETERS:  sleep_state         - Which sleep state we just exited
 210  *
 211  * RETURN:      Status
 212  *
 213  * DESCRIPTION: Perform the first state of OS-independent ACPI cleanup after a
 214  *              sleep.
 215  *              Called with interrupts ENABLED.
 216  *
 217  ******************************************************************************/
 218
 219 acpi_status acpi_hw_legacy_wake_prep(u8 sleep_state)
 220 {
 221         acpi_status status;
 222         struct acpi_bit_register_info *sleep_type_reg_info;
 223         struct acpi_bit_register_info *sleep_enable_reg_info;
 224         u32 pm1a_control;
 225         u32 pm1b_control;
 226
 227         ACPI_FUNCTION_TRACE(hw_legacy_wake_prep);
 228
 229         /*
 230          * Set SLP_TYPE and SLP_EN to state S0.
 231          * This is unclear from the ACPI Spec, but it is required
 232          * by some machines.
 233          */
 234         status = acpi_get_sleep_type_data(ACPI_STATE_S0,
 235                                           &acpi_gbl_sleep_type_a,
 236                                           &acpi_gbl_sleep_type_b);
 237         if (ACPI_SUCCESS(status)) {
 238                 sleep_type_reg_info =
 239                     acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_TYPE);
 240                 sleep_enable_reg_info =
 241                     acpi_hw_get_bit_register_info(ACPI_BITREG_SLEEP_ENABLE);
 242
 243                 /* Get current value of PM1A control */
 244
 245                 status = acpi_hw_register_read(ACPI_REGISTER_PM1_CONTROL,
 246                                                &pm1a_control);
 247                 if (ACPI_SUCCESS(status)) {
 248
 249                         /* Clear the SLP_EN and SLP_TYP fields */
 250
 251                         pm1a_control &= ~(sleep_type_reg_info->access_bit_mask |
 252                                           sleep_enable_reg_info->
 253                                           access_bit_mask);
 254                         pm1b_control = pm1a_control;
 255
 256                         /* Insert the SLP_TYP bits */
 257
 258                         pm1a_control |= (acpi_gbl_sleep_type_a <<
 259                                          sleep_type_reg_info->bit_position);
 260                         pm1b_control |= (acpi_gbl_sleep_type_b <<
 261                                          sleep_type_reg_info->bit_position);
 262
 263                         /* Write the control registers and ignore any errors */
 264
 265                         (void)acpi_hw_write_pm1_control(pm1a_control,
 266                                                         pm1b_control);
 267                 }
 268         }
 269
 270         return_ACPI_STATUS(status);
 271 }
 272
 273 /*******************************************************************************
 274  *
 275  * FUNCTION:    acpi_hw_legacy_wake
 276  *
 277  * PARAMETERS:  sleep_state         - Which sleep state we just exited
 278  *
 279  * RETURN:      Status
 280  *
 281  * DESCRIPTION: Perform OS-independent ACPI cleanup after a sleep
 282  *              Called with interrupts ENABLED.
 283  *
 284  ******************************************************************************/
 285
 286 acpi_status acpi_hw_legacy_wake(u8 sleep_state)
 287 {
 288         acpi_status status;
 289
 290         ACPI_FUNCTION_TRACE(hw_legacy_wake);
 291
 292         /* Ensure enter_sleep_state_prep -> enter_sleep_state ordering */
 293
 294         acpi_gbl_sleep_type_a = ACPI_SLEEP_TYPE_INVALID;
 295         acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST, ACPI_SST_WAKING);
 296
 297         /*
 298          * GPEs must be enabled before _WAK is called as GPEs
 299          * might get fired there
 300          *
 301          * Restore the GPEs:
 302          * 1) Disable/Clear all GPEs
 303          * 2) Enable all runtime GPEs
 304          */
 305         status = acpi_hw_disable_all_gpes();
 306         if (ACPI_FAILURE(status)) {
 307                 return_ACPI_STATUS(status);
 308         }
 309
 310         status = acpi_hw_enable_all_runtime_gpes();
 311         if (ACPI_FAILURE(status)) {
 312                 return_ACPI_STATUS(status);
 313         }
 314
 315         /*
 316          * Now we can execute _WAK, etc. Some machines require that the GPEs
 317          * are enabled before the wake methods are executed.
 318          */
 319         acpi_hw_execute_sleep_method(METHOD_PATHNAME__WAK, sleep_state);
 320
 321         /*
 322          * Some BIOS code assumes that WAK_STS will be cleared on resume
 323          * and use it to determine whether the system is rebooting or
 324          * resuming. Clear WAK_STS for compatibility.
 325          */
 326         acpi_write_bit_register(ACPI_BITREG_WAKE_STATUS, 1);
 327         acpi_gbl_system_awake_and_running = TRUE;
 328
 329         /* Enable power button */
 330
 331         (void)
 332             acpi_write_bit_register(acpi_gbl_fixed_event_info
 333                                     [ACPI_EVENT_POWER_BUTTON].
 334                                     enable_register_id, ACPI_ENABLE_EVENT);
 335
 336         (void)
 337             acpi_write_bit_register(acpi_gbl_fixed_event_info
 338                                     [ACPI_EVENT_POWER_BUTTON].
 339                                     status_register_id, ACPI_CLEAR_STATUS);
 340
 341         acpi_hw_execute_sleep_method(METHOD_PATHNAME__SST, ACPI_SST_WORKING);
 342         return_ACPI_STATUS(status);
 343 }
 344
 345 #endif                          /* !ACPI_REDUCED_HARDWARE */