drivers/acpi/x86/s2idle.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Architecture-specific ACPI-based support for suspend-to-idle.
   4  *
   5  * Author: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
   6  * Author: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
   7  * Author: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
   8  *
   9  * On platforms supporting the Low Power S0 Idle interface there is an ACPI
  10  * device object with the PNP0D80 compatible device ID (System Power Management
  11  * Controller) and a specific _DSM method under it.  That method, if present,
  12  * can be used to indicate to the platform that the OS is transitioning into a
  13  * low-power state in which certain types of activity are not desirable or that
  14  * it is leaving such a state, which allows the platform to adjust its operation
  15  * mode accordingly.
  16  */
  17
  18 #include <linux/acpi.h>
  19 #include <linux/device.h>
  20 #include <linux/suspend.h>
  21
  22 #include "../sleep.h"
  23
  24 #ifdef CONFIG_SUSPEND
  25
  26 static bool sleep_no_lps0 __read_mostly;
  27 module_param(sleep_no_lps0, bool, 0644);
  28 MODULE_PARM_DESC(sleep_no_lps0, "Do not use the special LPS0 device interface");
  29
  30 static const struct acpi_device_id lps0_device_ids[] = {
  31         {"PNP0D80", },
  32         {"", },
  33 };
  34
  35 #define ACPI_LPS0_DSM_UUID      "c4eb40a0-6cd2-11e2-bcfd-0800200c9a66"
  36
  37 #define ACPI_LPS0_GET_DEVICE_CONSTRAINTS        1
  38 #define ACPI_LPS0_SCREEN_OFF    3
  39 #define ACPI_LPS0_SCREEN_ON     4
  40 #define ACPI_LPS0_ENTRY         5
  41 #define ACPI_LPS0_EXIT          6
  42
  43 /* AMD */
  44 #define ACPI_LPS0_DSM_UUID_AMD      "e3f32452-febc-43ce-9039-932122d37721"
  45 #define ACPI_LPS0_SCREEN_OFF_AMD    4
  46 #define ACPI_LPS0_SCREEN_ON_AMD     5
  47
  48 static acpi_handle lps0_device_handle;
  49 static guid_t lps0_dsm_guid;
  50 static char lps0_dsm_func_mask;
  51
  52 /* Device constraint entry structure */
  53 struct lpi_device_info {
  54         char *name;
  55         int enabled;
  56         union acpi_object *package;
  57 };
  58
  59 /* Constraint package structure */
  60 struct lpi_device_constraint {
  61         int uid;
  62         int min_dstate;
  63         int function_states;
  64 };
  65
  66 struct lpi_constraints {
  67         acpi_handle handle;
  68         int min_dstate;
  69 };
  70
  71 /* AMD */
  72 /* Device constraint entry structure */
  73 struct lpi_device_info_amd {
  74         int revision;
  75         int count;
  76         union acpi_object *package;
  77 };
  78
  79 /* Constraint package structure */
  80 struct lpi_device_constraint_amd {
  81         char *name;
  82         int enabled;
  83         int function_states;
  84         int min_dstate;
  85 };
  86
  87 static struct lpi_constraints *lpi_constraints_table;
  88 static int lpi_constraints_table_size;
  89 static int rev_id;
  90
  91 static void lpi_device_get_constraints_amd(void)
  92 {
  93         union acpi_object *out_obj;
  94         int i, j, k;
  95
  96         out_obj = acpi_evaluate_dsm_typed(lps0_device_handle, &lps0_dsm_guid,
  97                                           1, ACPI_LPS0_GET_DEVICE_CONSTRAINTS,
  98                                           NULL, ACPI_TYPE_PACKAGE);
  99
 100         if (!out_obj)
 101                 return;
 102
 103         acpi_handle_debug(lps0_device_handle, "_DSM function 1 eval %s\n",
 104                           out_obj ? "successful" : "failed");
 105
 106         for (i = 0; i < out_obj->package.count; i++) {
 107                 union acpi_object *package = &out_obj->package.elements[i];
 108
 109                 if (package->type == ACPI_TYPE_PACKAGE) {
 110                         lpi_constraints_table = kcalloc(package->package.count,
 111                                                         sizeof(*lpi_constraints_table),
 112                                                         GFP_KERNEL);
 113
 114                         if (!lpi_constraints_table)
 115                                 goto free_acpi_buffer;
 116
 117                         acpi_handle_debug(lps0_device_handle,
 118                                           "LPI: constraints list begin:\n");
 119
 120                         for (j = 0; j < package->package.count; ++j) {
 121                                 union acpi_object *info_obj = &package->package.elements[j];
 122                                 struct lpi_device_constraint_amd dev_info = {};
 123                                 struct lpi_constraints *list;
 124                                 acpi_status status;
 125
 126                                 for (k = 0; k < info_obj->package.count; ++k) {
 127                                         union acpi_object *obj = &info_obj->package.elements[k];
 128
 129                                         list = &lpi_constraints_table[lpi_constraints_table_size];
 130                                         list->min_dstate = -1;
 131
 132                                         switch (k) {
 133                                         case 0:
 134                                                 dev_info.enabled = obj->integer.value;
 135                                                 break;
 136                                         case 1:
 137                                                 dev_info.name = obj->string.pointer;
 138                                                 break;
 139                                         case 2:
 140                                                 dev_info.function_states = obj->integer.value;
 141                                                 break;
 142                                         case 3:
 143                                                 dev_info.min_dstate = obj->integer.value;
 144                                                 break;
 145                                         }
 146
 147                                         if (!dev_info.enabled || !dev_info.name ||
 148                                             !dev_info.min_dstate)
 149                                                 continue;
 150
 151                                         status = acpi_get_handle(NULL, dev_info.name,
 152                                                                  &list->handle);
 153                                         if (ACPI_FAILURE(status))
 154                                                 continue;
 155
 156                                         acpi_handle_debug(lps0_device_handle,
 157                                                           "Name:%s\n", dev_info.name);
 158
 159                                         list->min_dstate = dev_info.min_dstate;
 160
 161                                         if (list->min_dstate < 0) {
 162                                                 acpi_handle_debug(lps0_device_handle,
 163                                                                   "Incomplete constraint defined\n");
 164                                                 continue;
 165                                         }
 166                                 }
 167                                 lpi_constraints_table_size++;
 168                         }
 169                 }
 170         }
 171
 172         acpi_handle_debug(lps0_device_handle, "LPI: constraints list end\n");
 173
 174 free_acpi_buffer:
 175         ACPI_FREE(out_obj);
 176 }
 177
 178 static void lpi_device_get_constraints(void)
 179 {
 180         union acpi_object *out_obj;
 181         int i;
 182
 183         out_obj = acpi_evaluate_dsm_typed(lps0_device_handle, &lps0_dsm_guid,
 184                                           1, ACPI_LPS0_GET_DEVICE_CONSTRAINTS,
 185                                           NULL, ACPI_TYPE_PACKAGE);
 186
 187         acpi_handle_debug(lps0_device_handle, "_DSM function 1 eval %s\n",
 188                           out_obj ? "successful" : "failed");
 189
 190         if (!out_obj)
 191                 return;
 192
 193         lpi_constraints_table = kcalloc(out_obj->package.count,
 194                                         sizeof(*lpi_constraints_table),
 195                                         GFP_KERNEL);
 196         if (!lpi_constraints_table)
 197                 goto free_acpi_buffer;
 198
 199         acpi_handle_debug(lps0_device_handle, "LPI: constraints list begin:\n");
 200
 201         for (i = 0; i < out_obj->package.count; i++) {
 202                 struct lpi_constraints *constraint;
 203                 acpi_status status;
 204                 union acpi_object *package = &out_obj->package.elements[i];
 205                 struct lpi_device_info info = { };
 206                 int package_count = 0, j;
 207
 208                 if (!package)
 209                         continue;
 210
 211                 for (j = 0; j < package->package.count; ++j) {
 212                         union acpi_object *element =
 213                                         &(package->package.elements[j]);
 214
 215                         switch (element->type) {
 216                         case ACPI_TYPE_INTEGER:
 217                                 info.enabled = element->integer.value;
 218                                 break;
 219                         case ACPI_TYPE_STRING:
 220                                 info.name = element->string.pointer;
 221                                 break;
 222                         case ACPI_TYPE_PACKAGE:
 223                                 package_count = element->package.count;
 224                                 info.package = element->package.elements;
 225                                 break;
 226                         }
 227                 }
 228
 229                 if (!info.enabled || !info.package || !info.name)
 230                         continue;
 231
 232                 constraint = &lpi_constraints_table[lpi_constraints_table_size];
 233
 234                 status = acpi_get_handle(NULL, info.name, &constraint->handle);
 235                 if (ACPI_FAILURE(status))
 236                         continue;
 237
 238                 acpi_handle_debug(lps0_device_handle,
 239                                   "index:%d Name:%s\n", i, info.name);
 240
 241                 constraint->min_dstate = -1;
 242
 243                 for (j = 0; j < package_count; ++j) {
 244                         union acpi_object *info_obj = &info.package[j];
 245                         union acpi_object *cnstr_pkg;
 246                         union acpi_object *obj;
 247                         struct lpi_device_constraint dev_info;
 248
 249                         switch (info_obj->type) {
 250                         case ACPI_TYPE_INTEGER:
 251                                 /* version */
 252                                 break;
 253                         case ACPI_TYPE_PACKAGE:
 254                                 if (info_obj->package.count < 2)
 255                                         break;
 256
 257                                 cnstr_pkg = info_obj->package.elements;
 258                                 obj = &cnstr_pkg[0];
 259                                 dev_info.uid = obj->integer.value;
 260                                 obj = &cnstr_pkg[1];
 261                                 dev_info.min_dstate = obj->integer.value;
 262
 263                                 acpi_handle_debug(lps0_device_handle,
 264                                         "uid:%d min_dstate:%s\n",
 265                                         dev_info.uid,
 266                                         acpi_power_state_string(dev_info.min_dstate));
 267
 268                                 constraint->min_dstate = dev_info.min_dstate;
 269                                 break;
 270                         }
 271                 }
 272
 273                 if (constraint->min_dstate < 0) {
 274                         acpi_handle_debug(lps0_device_handle,
 275                                           "Incomplete constraint defined\n");
 276                         continue;
 277                 }
 278
 279                 lpi_constraints_table_size++;
 280         }
 281
 282         acpi_handle_debug(lps0_device_handle, "LPI: constraints list end\n");
 283
 284 free_acpi_buffer:
 285         ACPI_FREE(out_obj);
 286 }
 287
 288 static void lpi_check_constraints(void)
 289 {
 290         int i;
 291
 292         for (i = 0; i < lpi_constraints_table_size; ++i) {
 293                 acpi_handle handle = lpi_constraints_table[i].handle;
 294                 struct acpi_device *adev;
 295
 296                 if (!handle || acpi_bus_get_device(handle, &adev))
 297                         continue;
 298
 299                 acpi_handle_debug(handle,
 300                         "LPI: required min power state:%s current power state:%s\n",
 301                         acpi_power_state_string(lpi_constraints_table[i].min_dstate),
 302                         acpi_power_state_string(adev->power.state));
 303
 304                 if (!adev->flags.power_manageable) {
 305                         acpi_handle_info(handle, "LPI: Device not power manageable\n");
 306                         lpi_constraints_table[i].handle = NULL;
 307                         continue;
 308                 }
 309
 310                 if (adev->power.state < lpi_constraints_table[i].min_dstate)
 311                         acpi_handle_info(handle,
 312                                 "LPI: Constraint not met; min power state:%s current power state:%s\n",
 313                                 acpi_power_state_string(lpi_constraints_table[i].min_dstate),
 314                                 acpi_power_state_string(adev->power.state));
 315         }
 316 }
 317
 318 static void acpi_sleep_run_lps0_dsm(unsigned int func)
 319 {
 320         union acpi_object *out_obj;
 321
 322         if (!(lps0_dsm_func_mask & (1 << func)))
 323                 return;
 324
 325         out_obj = acpi_evaluate_dsm(lps0_device_handle, &lps0_dsm_guid, rev_id, func, NULL);
 326         ACPI_FREE(out_obj);
 327
 328         acpi_handle_debug(lps0_device_handle, "_DSM function %u evaluation %s\n",
 329                           func, out_obj ? "successful" : "failed");
 330 }
 331
 332 static bool acpi_s2idle_vendor_amd(void)
 333 {
 334         return boot_cpu_data.x86_vendor == X86_VENDOR_AMD;
 335 }
 336
 337 static int lps0_device_attach(struct acpi_device *adev,
 338                               const struct acpi_device_id *not_used)
 339 {
 340         union acpi_object *out_obj;
 341
 342         if (lps0_device_handle)
 343                 return 0;
 344
 345         if (!(acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0))
 346                 return 0;
 347
 348         if (acpi_s2idle_vendor_amd()) {
 349                 guid_parse(ACPI_LPS0_DSM_UUID_AMD, &lps0_dsm_guid);
 350                 out_obj = acpi_evaluate_dsm(adev->handle, &lps0_dsm_guid, 0, 0, NULL);
 351                 rev_id = 0;
 352         } else {
 353                 guid_parse(ACPI_LPS0_DSM_UUID, &lps0_dsm_guid);
 354                 out_obj = acpi_evaluate_dsm(adev->handle, &lps0_dsm_guid, 1, 0, NULL);
 355                 rev_id = 1;
 356         }
 357
 358         /* Check if the _DSM is present and as expected. */
 359         if (!out_obj || out_obj->type != ACPI_TYPE_BUFFER) {
 360                 acpi_handle_debug(adev->handle,
 361                                   "_DSM function 0 evaluation failed\n");
 362                 return 0;
 363         }
 364
 365         lps0_dsm_func_mask = *(char *)out_obj->buffer.pointer;
 366
 367         ACPI_FREE(out_obj);
 368
 369         acpi_handle_debug(adev->handle, "_DSM function mask: 0x%x\n",
 370                           lps0_dsm_func_mask);
 371
 372         lps0_device_handle = adev->handle;
 373
 374         if (acpi_s2idle_vendor_amd())
 375                 lpi_device_get_constraints_amd();
 376         else
 377                 lpi_device_get_constraints();
 378
 379         /*
 380          * Use suspend-to-idle by default if the default suspend mode was not
 381          * set from the command line.
 382          */
 383         if (mem_sleep_default > PM_SUSPEND_MEM && !acpi_sleep_default_s3)
 384                 mem_sleep_current = PM_SUSPEND_TO_IDLE;
 385
 386         /*
 387          * Some LPS0 systems, like ASUS Zenbook UX430UNR/i7-8550U, require the
 388          * EC GPE to be enabled while suspended for certain wakeup devices to
 389          * work, so mark it as wakeup-capable.
 390          */
 391         acpi_ec_mark_gpe_for_wake();
 392
 393         return 0;
 394 }
 395
 396 static struct acpi_scan_handler lps0_handler = {
 397         .ids = lps0_device_ids,
 398         .attach = lps0_device_attach,
 399 };
 400
 401 int acpi_s2idle_prepare_late(void)
 402 {
 403         if (!lps0_device_handle || sleep_no_lps0)
 404                 return 0;
 405
 406         if (pm_debug_messages_on)
 407                 lpi_check_constraints();
 408
 409         if (acpi_s2idle_vendor_amd()) {
 410                 acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_OFF_AMD);
 411         } else {
 412                 acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_OFF);
 413                 acpi_sleep_run_lps0_dsm(ACPI_LPS0_ENTRY);
 414         }
 415
 416         return 0;
 417 }
 418
 419 void acpi_s2idle_restore_early(void)
 420 {
 421         if (!lps0_device_handle || sleep_no_lps0)
 422                 return;
 423
 424         if (acpi_s2idle_vendor_amd()) {
 425                 acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_ON_AMD);
 426         } else {
 427                 acpi_sleep_run_lps0_dsm(ACPI_LPS0_EXIT);
 428                 acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_ON);
 429         }
 430 }
 431
 432 static const struct platform_s2idle_ops acpi_s2idle_ops_lps0 = {
 433         .begin = acpi_s2idle_begin,
 434         .prepare = acpi_s2idle_prepare,
 435         .prepare_late = acpi_s2idle_prepare_late,
 436         .wake = acpi_s2idle_wake,
 437         .restore_early = acpi_s2idle_restore_early,
 438         .restore = acpi_s2idle_restore,
 439         .end = acpi_s2idle_end,
 440 };
 441
 442 void acpi_s2idle_setup(void)
 443 {
 444         acpi_scan_add_handler(&lps0_handler);
 445         s2idle_set_ops(&acpi_s2idle_ops_lps0);
 446 }
 447
 448 #endif /* CONFIG_SUSPEND */