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                 struct lpi_device_info_amd info = { };
 109
 110                 if (package->type == ACPI_TYPE_INTEGER) {
 111                         switch (i) {
 112                         case 0:
 113                                 info.revision = package->integer.value;
 114                                 break;
 115                         case 1:
 116                                 info.count = package->integer.value;
 117                                 break;
 118                         }
 119                 } else if (package->type == ACPI_TYPE_PACKAGE) {
 120                         lpi_constraints_table = kcalloc(package->package.count,
 121                                                         sizeof(*lpi_constraints_table),
 122                                                         GFP_KERNEL);
 123
 124                         if (!lpi_constraints_table)
 125                                 goto free_acpi_buffer;
 126
 127                         acpi_handle_debug(lps0_device_handle,
 128                                           "LPI: constraints list begin:\n");
 129
 130                         for (j = 0; j < package->package.count; ++j) {
 131                                 union acpi_object *info_obj = &package->package.elements[j];
 132                                 struct lpi_device_constraint_amd dev_info = {};
 133                                 struct lpi_constraints *list;
 134                                 acpi_status status;
 135
 136                                 for (k = 0; k < info_obj->package.count; ++k) {
 137                                         union acpi_object *obj = &info_obj->package.elements[k];
 138                                         union acpi_object *obj_new;
 139
 140                                         list = &lpi_constraints_table[lpi_constraints_table_size];
 141                                         list->min_dstate = -1;
 142
 143                                         obj_new = &obj[k];
 144                                         switch (k) {
 145                                         case 0:
 146                                                 dev_info.enabled = obj->integer.value;
 147                                                 break;
 148                                         case 1:
 149                                                 dev_info.name = obj->string.pointer;
 150                                                 break;
 151                                         case 2:
 152                                                 dev_info.function_states = obj->integer.value;
 153                                                 break;
 154                                         case 3:
 155                                                 dev_info.min_dstate = obj->integer.value;
 156                                                 break;
 157                                         }
 158
 159                                         if (!dev_info.enabled || !dev_info.name ||
 160                                             !dev_info.min_dstate)
 161                                                 continue;
 162
 163                                         status = acpi_get_handle(NULL, dev_info.name,
 164                                                                  &list->handle);
 165                                         if (ACPI_FAILURE(status))
 166                                                 continue;
 167
 168                                         acpi_handle_debug(lps0_device_handle,
 169                                                           "Name:%s\n", dev_info.name);
 170
 171                                         list->min_dstate = dev_info.min_dstate;
 172
 173                                         if (list->min_dstate < 0) {
 174                                                 acpi_handle_debug(lps0_device_handle,
 175                                                                   "Incomplete constraint defined\n");
 176                                                 continue;
 177                                         }
 178                                 }
 179                                 lpi_constraints_table_size++;
 180                         }
 181                 }
 182         }
 183
 184         acpi_handle_debug(lps0_device_handle, "LPI: constraints list end\n");
 185
 186 free_acpi_buffer:
 187         ACPI_FREE(out_obj);
 188 }
 189
 190 static void lpi_device_get_constraints(void)
 191 {
 192         union acpi_object *out_obj;
 193         int i;
 194
 195         out_obj = acpi_evaluate_dsm_typed(lps0_device_handle, &lps0_dsm_guid,
 196                                           1, ACPI_LPS0_GET_DEVICE_CONSTRAINTS,
 197                                           NULL, ACPI_TYPE_PACKAGE);
 198
 199         acpi_handle_debug(lps0_device_handle, "_DSM function 1 eval %s\n",
 200                           out_obj ? "successful" : "failed");
 201
 202         if (!out_obj)
 203                 return;
 204
 205         lpi_constraints_table = kcalloc(out_obj->package.count,
 206                                         sizeof(*lpi_constraints_table),
 207                                         GFP_KERNEL);
 208         if (!lpi_constraints_table)
 209                 goto free_acpi_buffer;
 210
 211         acpi_handle_debug(lps0_device_handle, "LPI: constraints list begin:\n");
 212
 213         for (i = 0; i < out_obj->package.count; i++) {
 214                 struct lpi_constraints *constraint;
 215                 acpi_status status;
 216                 union acpi_object *package = &out_obj->package.elements[i];
 217                 struct lpi_device_info info = { };
 218                 int package_count = 0, j;
 219
 220                 if (!package)
 221                         continue;
 222
 223                 for (j = 0; j < package->package.count; ++j) {
 224                         union acpi_object *element =
 225                                         &(package->package.elements[j]);
 226
 227                         switch (element->type) {
 228                         case ACPI_TYPE_INTEGER:
 229                                 info.enabled = element->integer.value;
 230                                 break;
 231                         case ACPI_TYPE_STRING:
 232                                 info.name = element->string.pointer;
 233                                 break;
 234                         case ACPI_TYPE_PACKAGE:
 235                                 package_count = element->package.count;
 236                                 info.package = element->package.elements;
 237                                 break;
 238                         }
 239                 }
 240
 241                 if (!info.enabled || !info.package || !info.name)
 242                         continue;
 243
 244                 constraint = &lpi_constraints_table[lpi_constraints_table_size];
 245
 246                 status = acpi_get_handle(NULL, info.name, &constraint->handle);
 247                 if (ACPI_FAILURE(status))
 248                         continue;
 249
 250                 acpi_handle_debug(lps0_device_handle,
 251                                   "index:%d Name:%s\n", i, info.name);
 252
 253                 constraint->min_dstate = -1;
 254
 255                 for (j = 0; j < package_count; ++j) {
 256                         union acpi_object *info_obj = &info.package[j];
 257                         union acpi_object *cnstr_pkg;
 258                         union acpi_object *obj;
 259                         struct lpi_device_constraint dev_info;
 260
 261                         switch (info_obj->type) {
 262                         case ACPI_TYPE_INTEGER:
 263                                 /* version */
 264                                 break;
 265                         case ACPI_TYPE_PACKAGE:
 266                                 if (info_obj->package.count < 2)
 267                                         break;
 268
 269                                 cnstr_pkg = info_obj->package.elements;
 270                                 obj = &cnstr_pkg[0];
 271                                 dev_info.uid = obj->integer.value;
 272                                 obj = &cnstr_pkg[1];
 273                                 dev_info.min_dstate = obj->integer.value;
 274
 275                                 acpi_handle_debug(lps0_device_handle,
 276                                         "uid:%d min_dstate:%s\n",
 277                                         dev_info.uid,
 278                                         acpi_power_state_string(dev_info.min_dstate));
 279
 280                                 constraint->min_dstate = dev_info.min_dstate;
 281                                 break;
 282                         }
 283                 }
 284
 285                 if (constraint->min_dstate < 0) {
 286                         acpi_handle_debug(lps0_device_handle,
 287                                           "Incomplete constraint defined\n");
 288                         continue;
 289                 }
 290
 291                 lpi_constraints_table_size++;
 292         }
 293
 294         acpi_handle_debug(lps0_device_handle, "LPI: constraints list end\n");
 295
 296 free_acpi_buffer:
 297         ACPI_FREE(out_obj);
 298 }
 299
 300 static void lpi_check_constraints(void)
 301 {
 302         int i;
 303
 304         for (i = 0; i < lpi_constraints_table_size; ++i) {
 305                 acpi_handle handle = lpi_constraints_table[i].handle;
 306                 struct acpi_device *adev;
 307
 308                 if (!handle || acpi_bus_get_device(handle, &adev))
 309                         continue;
 310
 311                 acpi_handle_debug(handle,
 312                         "LPI: required 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                 if (!adev->flags.power_manageable) {
 317                         acpi_handle_info(handle, "LPI: Device not power manageable\n");
 318                         lpi_constraints_table[i].handle = NULL;
 319                         continue;
 320                 }
 321
 322                 if (adev->power.state < lpi_constraints_table[i].min_dstate)
 323                         acpi_handle_info(handle,
 324                                 "LPI: Constraint not met; min power state:%s current power state:%s\n",
 325                                 acpi_power_state_string(lpi_constraints_table[i].min_dstate),
 326                                 acpi_power_state_string(adev->power.state));
 327         }
 328 }
 329
 330 static void acpi_sleep_run_lps0_dsm(unsigned int func)
 331 {
 332         union acpi_object *out_obj;
 333
 334         if (!(lps0_dsm_func_mask & (1 << func)))
 335                 return;
 336
 337         out_obj = acpi_evaluate_dsm(lps0_device_handle, &lps0_dsm_guid, rev_id, func, NULL);
 338         ACPI_FREE(out_obj);
 339
 340         acpi_handle_debug(lps0_device_handle, "_DSM function %u evaluation %s\n",
 341                           func, out_obj ? "successful" : "failed");
 342 }
 343
 344 static bool acpi_s2idle_vendor_amd(void)
 345 {
 346         return boot_cpu_data.x86_vendor == X86_VENDOR_AMD;
 347 }
 348
 349 static int lps0_device_attach(struct acpi_device *adev,
 350                               const struct acpi_device_id *not_used)
 351 {
 352         union acpi_object *out_obj;
 353
 354         if (lps0_device_handle)
 355                 return 0;
 356
 357         if (!(acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0))
 358                 return 0;
 359
 360         if (acpi_s2idle_vendor_amd()) {
 361                 guid_parse(ACPI_LPS0_DSM_UUID_AMD, &lps0_dsm_guid);
 362                 out_obj = acpi_evaluate_dsm(adev->handle, &lps0_dsm_guid, 0, 0, NULL);
 363                 rev_id = 0;
 364         } else {
 365                 guid_parse(ACPI_LPS0_DSM_UUID, &lps0_dsm_guid);
 366                 out_obj = acpi_evaluate_dsm(adev->handle, &lps0_dsm_guid, 1, 0, NULL);
 367                 rev_id = 1;
 368         }
 369
 370         /* Check if the _DSM is present and as expected. */
 371         if (!out_obj || out_obj->type != ACPI_TYPE_BUFFER) {
 372                 acpi_handle_debug(adev->handle,
 373                                   "_DSM function 0 evaluation failed\n");
 374                 return 0;
 375         }
 376
 377         lps0_dsm_func_mask = *(char *)out_obj->buffer.pointer;
 378
 379         ACPI_FREE(out_obj);
 380
 381         acpi_handle_debug(adev->handle, "_DSM function mask: 0x%x\n",
 382                           lps0_dsm_func_mask);
 383
 384         lps0_device_handle = adev->handle;
 385
 386         if (acpi_s2idle_vendor_amd())
 387                 lpi_device_get_constraints_amd();
 388         else
 389                 lpi_device_get_constraints();
 390
 391         /*
 392          * Use suspend-to-idle by default if the default suspend mode was not
 393          * set from the command line.
 394          */
 395         if (mem_sleep_default > PM_SUSPEND_MEM && !acpi_sleep_default_s3)
 396                 mem_sleep_current = PM_SUSPEND_TO_IDLE;
 397
 398         /*
 399          * Some LPS0 systems, like ASUS Zenbook UX430UNR/i7-8550U, require the
 400          * EC GPE to be enabled while suspended for certain wakeup devices to
 401          * work, so mark it as wakeup-capable.
 402          */
 403         acpi_ec_mark_gpe_for_wake();
 404
 405         return 0;
 406 }
 407
 408 static struct acpi_scan_handler lps0_handler = {
 409         .ids = lps0_device_ids,
 410         .attach = lps0_device_attach,
 411 };
 412
 413 int acpi_s2idle_prepare_late(void)
 414 {
 415         if (!lps0_device_handle || sleep_no_lps0)
 416                 return 0;
 417
 418         if (pm_debug_messages_on)
 419                 lpi_check_constraints();
 420
 421         if (acpi_s2idle_vendor_amd()) {
 422                 acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_OFF_AMD);
 423         } else {
 424                 acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_OFF);
 425                 acpi_sleep_run_lps0_dsm(ACPI_LPS0_ENTRY);
 426         }
 427
 428         return 0;
 429 }
 430
 431 void acpi_s2idle_restore_early(void)
 432 {
 433         if (!lps0_device_handle || sleep_no_lps0)
 434                 return;
 435
 436         if (acpi_s2idle_vendor_amd()) {
 437                 acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_ON_AMD);
 438         } else {
 439                 acpi_sleep_run_lps0_dsm(ACPI_LPS0_EXIT);
 440                 acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_ON);
 441         }
 442 }
 443
 444 static const struct platform_s2idle_ops acpi_s2idle_ops_lps0 = {
 445         .begin = acpi_s2idle_begin,
 446         .prepare = acpi_s2idle_prepare,
 447         .prepare_late = acpi_s2idle_prepare_late,
 448         .wake = acpi_s2idle_wake,
 449         .restore_early = acpi_s2idle_restore_early,
 450         .restore = acpi_s2idle_restore,
 451         .end = acpi_s2idle_end,
 452 };
 453
 454 void acpi_s2idle_setup(void)
 455 {
 456         acpi_scan_add_handler(&lps0_handler);
 457         s2idle_set_ops(&acpi_s2idle_ops_lps0);
 458 }
 459
 460 #endif /* CONFIG_SUSPEND */