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_ENTRY_AMD         2
  46 #define ACPI_LPS0_EXIT_AMD          3
  47 #define ACPI_LPS0_SCREEN_OFF_AMD    4
  48 #define ACPI_LPS0_SCREEN_ON_AMD     5
  49
  50 static acpi_handle lps0_device_handle;
  51 static guid_t lps0_dsm_guid;
  52 static char lps0_dsm_func_mask;
  53
  54 /* Device constraint entry structure */
  55 struct lpi_device_info {
  56         char *name;
  57         int enabled;
  58         union acpi_object *package;
  59 };
  60
  61 /* Constraint package structure */
  62 struct lpi_device_constraint {
  63         int uid;
  64         int min_dstate;
  65         int function_states;
  66 };
  67
  68 struct lpi_constraints {
  69         acpi_handle handle;
  70         int min_dstate;
  71 };
  72
  73 /* AMD */
  74 /* Device constraint entry structure */
  75 struct lpi_device_info_amd {
  76         int revision;
  77         int count;
  78         union acpi_object *package;
  79 };
  80
  81 /* Constraint package structure */
  82 struct lpi_device_constraint_amd {
  83         char *name;
  84         int enabled;
  85         int function_states;
  86         int min_dstate;
  87 };
  88
  89 static struct lpi_constraints *lpi_constraints_table;
  90 static int lpi_constraints_table_size;
  91 static int rev_id;
  92
  93 static void lpi_device_get_constraints_amd(void)
  94 {
  95         union acpi_object *out_obj;
  96         int i, j, k;
  97
  98         out_obj = acpi_evaluate_dsm_typed(lps0_device_handle, &lps0_dsm_guid,
  99                                           1, ACPI_LPS0_GET_DEVICE_CONSTRAINTS,
 100                                           NULL, ACPI_TYPE_PACKAGE);
 101
 102         if (!out_obj)
 103                 return;
 104
 105         acpi_handle_debug(lps0_device_handle, "_DSM function 1 eval %s\n",
 106                           out_obj ? "successful" : "failed");
 107
 108         for (i = 0; i < out_obj->package.count; i++) {
 109                 union acpi_object *package = &out_obj->package.elements[i];
 110
 111                 if (package->type == ACPI_TYPE_PACKAGE) {
 112                         lpi_constraints_table = kcalloc(package->package.count,
 113                                                         sizeof(*lpi_constraints_table),
 114                                                         GFP_KERNEL);
 115
 116                         if (!lpi_constraints_table)
 117                                 goto free_acpi_buffer;
 118
 119                         acpi_handle_debug(lps0_device_handle,
 120                                           "LPI: constraints list begin:\n");
 121
 122                         for (j = 0; j < package->package.count; ++j) {
 123                                 union acpi_object *info_obj = &package->package.elements[j];
 124                                 struct lpi_device_constraint_amd dev_info = {};
 125                                 struct lpi_constraints *list;
 126                                 acpi_status status;
 127
 128                                 for (k = 0; k < info_obj->package.count; ++k) {
 129                                         union acpi_object *obj = &info_obj->package.elements[k];
 130
 131                                         list = &lpi_constraints_table[lpi_constraints_table_size];
 132                                         list->min_dstate = -1;
 133
 134                                         switch (k) {
 135                                         case 0:
 136                                                 dev_info.enabled = obj->integer.value;
 137                                                 break;
 138                                         case 1:
 139                                                 dev_info.name = obj->string.pointer;
 140                                                 break;
 141                                         case 2:
 142                                                 dev_info.function_states = obj->integer.value;
 143                                                 break;
 144                                         case 3:
 145                                                 dev_info.min_dstate = obj->integer.value;
 146                                                 break;
 147                                         }
 148
 149                                         if (!dev_info.enabled || !dev_info.name ||
 150                                             !dev_info.min_dstate)
 151                                                 continue;
 152
 153                                         status = acpi_get_handle(NULL, dev_info.name,
 154                                                                  &list->handle);
 155                                         if (ACPI_FAILURE(status))
 156                                                 continue;
 157
 158                                         acpi_handle_debug(lps0_device_handle,
 159                                                           "Name:%s\n", dev_info.name);
 160
 161                                         list->min_dstate = dev_info.min_dstate;
 162
 163                                         if (list->min_dstate < 0) {
 164                                                 acpi_handle_debug(lps0_device_handle,
 165                                                                   "Incomplete constraint defined\n");
 166                                                 continue;
 167                                         }
 168                                 }
 169                                 lpi_constraints_table_size++;
 170                         }
 171                 }
 172         }
 173
 174         acpi_handle_debug(lps0_device_handle, "LPI: constraints list end\n");
 175
 176 free_acpi_buffer:
 177         ACPI_FREE(out_obj);
 178 }
 179
 180 static void lpi_device_get_constraints(void)
 181 {
 182         union acpi_object *out_obj;
 183         int i;
 184
 185         out_obj = acpi_evaluate_dsm_typed(lps0_device_handle, &lps0_dsm_guid,
 186                                           1, ACPI_LPS0_GET_DEVICE_CONSTRAINTS,
 187                                           NULL, ACPI_TYPE_PACKAGE);
 188
 189         acpi_handle_debug(lps0_device_handle, "_DSM function 1 eval %s\n",
 190                           out_obj ? "successful" : "failed");
 191
 192         if (!out_obj)
 193                 return;
 194
 195         lpi_constraints_table = kcalloc(out_obj->package.count,
 196                                         sizeof(*lpi_constraints_table),
 197                                         GFP_KERNEL);
 198         if (!lpi_constraints_table)
 199                 goto free_acpi_buffer;
 200
 201         acpi_handle_debug(lps0_device_handle, "LPI: constraints list begin:\n");
 202
 203         for (i = 0; i < out_obj->package.count; i++) {
 204                 struct lpi_constraints *constraint;
 205                 acpi_status status;
 206                 union acpi_object *package = &out_obj->package.elements[i];
 207                 struct lpi_device_info info = { };
 208                 int package_count = 0, j;
 209
 210                 if (!package)
 211                         continue;
 212
 213                 for (j = 0; j < package->package.count; ++j) {
 214                         union acpi_object *element =
 215                                         &(package->package.elements[j]);
 216
 217                         switch (element->type) {
 218                         case ACPI_TYPE_INTEGER:
 219                                 info.enabled = element->integer.value;
 220                                 break;
 221                         case ACPI_TYPE_STRING:
 222                                 info.name = element->string.pointer;
 223                                 break;
 224                         case ACPI_TYPE_PACKAGE:
 225                                 package_count = element->package.count;
 226                                 info.package = element->package.elements;
 227                                 break;
 228                         }
 229                 }
 230
 231                 if (!info.enabled || !info.package || !info.name)
 232                         continue;
 233
 234                 constraint = &lpi_constraints_table[lpi_constraints_table_size];
 235
 236                 status = acpi_get_handle(NULL, info.name, &constraint->handle);
 237                 if (ACPI_FAILURE(status))
 238                         continue;
 239
 240                 acpi_handle_debug(lps0_device_handle,
 241                                   "index:%d Name:%s\n", i, info.name);
 242
 243                 constraint->min_dstate = -1;
 244
 245                 for (j = 0; j < package_count; ++j) {
 246                         union acpi_object *info_obj = &info.package[j];
 247                         union acpi_object *cnstr_pkg;
 248                         union acpi_object *obj;
 249                         struct lpi_device_constraint dev_info;
 250
 251                         switch (info_obj->type) {
 252                         case ACPI_TYPE_INTEGER:
 253                                 /* version */
 254                                 break;
 255                         case ACPI_TYPE_PACKAGE:
 256                                 if (info_obj->package.count < 2)
 257                                         break;
 258
 259                                 cnstr_pkg = info_obj->package.elements;
 260                                 obj = &cnstr_pkg[0];
 261                                 dev_info.uid = obj->integer.value;
 262                                 obj = &cnstr_pkg[1];
 263                                 dev_info.min_dstate = obj->integer.value;
 264
 265                                 acpi_handle_debug(lps0_device_handle,
 266                                         "uid:%d min_dstate:%s\n",
 267                                         dev_info.uid,
 268                                         acpi_power_state_string(dev_info.min_dstate));
 269
 270                                 constraint->min_dstate = dev_info.min_dstate;
 271                                 break;
 272                         }
 273                 }
 274
 275                 if (constraint->min_dstate < 0) {
 276                         acpi_handle_debug(lps0_device_handle,
 277                                           "Incomplete constraint defined\n");
 278                         continue;
 279                 }
 280
 281                 lpi_constraints_table_size++;
 282         }
 283
 284         acpi_handle_debug(lps0_device_handle, "LPI: constraints list end\n");
 285
 286 free_acpi_buffer:
 287         ACPI_FREE(out_obj);
 288 }
 289
 290 static void lpi_check_constraints(void)
 291 {
 292         int i;
 293
 294         for (i = 0; i < lpi_constraints_table_size; ++i) {
 295                 acpi_handle handle = lpi_constraints_table[i].handle;
 296                 struct acpi_device *adev;
 297
 298                 if (!handle || acpi_bus_get_device(handle, &adev))
 299                         continue;
 300
 301                 acpi_handle_debug(handle,
 302                         "LPI: required min power state:%s current power state:%s\n",
 303                         acpi_power_state_string(lpi_constraints_table[i].min_dstate),
 304                         acpi_power_state_string(adev->power.state));
 305
 306                 if (!adev->flags.power_manageable) {
 307                         acpi_handle_info(handle, "LPI: Device not power manageable\n");
 308                         lpi_constraints_table[i].handle = NULL;
 309                         continue;
 310                 }
 311
 312                 if (adev->power.state < lpi_constraints_table[i].min_dstate)
 313                         acpi_handle_info(handle,
 314                                 "LPI: Constraint not met; min power state:%s current power state:%s\n",
 315                                 acpi_power_state_string(lpi_constraints_table[i].min_dstate),
 316                                 acpi_power_state_string(adev->power.state));
 317         }
 318 }
 319
 320 static void acpi_sleep_run_lps0_dsm(unsigned int func)
 321 {
 322         union acpi_object *out_obj;
 323
 324         if (!(lps0_dsm_func_mask & (1 << func)))
 325                 return;
 326
 327         out_obj = acpi_evaluate_dsm(lps0_device_handle, &lps0_dsm_guid, rev_id, func, NULL);
 328         ACPI_FREE(out_obj);
 329
 330         acpi_handle_debug(lps0_device_handle, "_DSM function %u evaluation %s\n",
 331                           func, out_obj ? "successful" : "failed");
 332 }
 333
 334 static bool acpi_s2idle_vendor_amd(void)
 335 {
 336         return boot_cpu_data.x86_vendor == X86_VENDOR_AMD;
 337 }
 338
 339 static int lps0_device_attach(struct acpi_device *adev,
 340                               const struct acpi_device_id *not_used)
 341 {
 342         union acpi_object *out_obj;
 343
 344         if (lps0_device_handle)
 345                 return 0;
 346
 347         if (!(acpi_gbl_FADT.flags & ACPI_FADT_LOW_POWER_S0))
 348                 return 0;
 349
 350         if (acpi_s2idle_vendor_amd()) {
 351                 guid_parse(ACPI_LPS0_DSM_UUID_AMD, &lps0_dsm_guid);
 352                 out_obj = acpi_evaluate_dsm(adev->handle, &lps0_dsm_guid, 0, 0, NULL);
 353                 rev_id = 0;
 354         } else {
 355                 guid_parse(ACPI_LPS0_DSM_UUID, &lps0_dsm_guid);
 356                 out_obj = acpi_evaluate_dsm(adev->handle, &lps0_dsm_guid, 1, 0, NULL);
 357                 rev_id = 1;
 358         }
 359
 360         /* Check if the _DSM is present and as expected. */
 361         if (!out_obj || out_obj->type != ACPI_TYPE_BUFFER) {
 362                 acpi_handle_debug(adev->handle,
 363                                   "_DSM function 0 evaluation failed\n");
 364                 return 0;
 365         }
 366
 367         lps0_dsm_func_mask = *(char *)out_obj->buffer.pointer;
 368
 369         ACPI_FREE(out_obj);
 370
 371         acpi_handle_debug(adev->handle, "_DSM function mask: 0x%x\n",
 372                           lps0_dsm_func_mask);
 373
 374         lps0_device_handle = adev->handle;
 375
 376         if (acpi_s2idle_vendor_amd())
 377                 lpi_device_get_constraints_amd();
 378         else
 379                 lpi_device_get_constraints();
 380
 381         /*
 382          * Use suspend-to-idle by default if the default suspend mode was not
 383          * set from the command line.
 384          */
 385         if (mem_sleep_default > PM_SUSPEND_MEM && !acpi_sleep_default_s3)
 386                 mem_sleep_current = PM_SUSPEND_TO_IDLE;
 387
 388         /*
 389          * Some LPS0 systems, like ASUS Zenbook UX430UNR/i7-8550U, require the
 390          * EC GPE to be enabled while suspended for certain wakeup devices to
 391          * work, so mark it as wakeup-capable.
 392          */
 393         acpi_ec_mark_gpe_for_wake();
 394
 395         return 0;
 396 }
 397
 398 static struct acpi_scan_handler lps0_handler = {
 399         .ids = lps0_device_ids,
 400         .attach = lps0_device_attach,
 401 };
 402
 403 int acpi_s2idle_prepare_late(void)
 404 {
 405         if (!lps0_device_handle || sleep_no_lps0)
 406                 return 0;
 407
 408         if (pm_debug_messages_on)
 409                 lpi_check_constraints();
 410
 411         if (acpi_s2idle_vendor_amd()) {
 412                 acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_OFF_AMD);
 413                 acpi_sleep_run_lps0_dsm(ACPI_LPS0_ENTRY_AMD);
 414         } else {
 415                 acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_OFF);
 416                 acpi_sleep_run_lps0_dsm(ACPI_LPS0_ENTRY);
 417         }
 418
 419         return 0;
 420 }
 421
 422 void acpi_s2idle_restore_early(void)
 423 {
 424         if (!lps0_device_handle || sleep_no_lps0)
 425                 return;
 426
 427         if (acpi_s2idle_vendor_amd()) {
 428                 acpi_sleep_run_lps0_dsm(ACPI_LPS0_EXIT_AMD);
 429                 acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_ON_AMD);
 430         } else {
 431                 acpi_sleep_run_lps0_dsm(ACPI_LPS0_EXIT);
 432                 acpi_sleep_run_lps0_dsm(ACPI_LPS0_SCREEN_ON);
 433         }
 434 }
 435
 436 static const struct platform_s2idle_ops acpi_s2idle_ops_lps0 = {
 437         .begin = acpi_s2idle_begin,
 438         .prepare = acpi_s2idle_prepare,
 439         .prepare_late = acpi_s2idle_prepare_late,
 440         .wake = acpi_s2idle_wake,
 441         .restore_early = acpi_s2idle_restore_early,
 442         .restore = acpi_s2idle_restore,
 443         .end = acpi_s2idle_end,
 444 };
 445
 446 void acpi_s2idle_setup(void)
 447 {
 448         acpi_scan_add_handler(&lps0_handler);
 449         s2idle_set_ops(&acpi_s2idle_ops_lps0);
 450 }
 451
 452 #endif /* CONFIG_SUSPEND */