drivers/opp/of.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Generic OPP OF helpers
   4  *
   5  * Copyright (C) 2009-2010 Texas Instruments Incorporated.
   6  *      Nishanth Menon
   7  *      Romit Dasgupta
   8  *      Kevin Hilman
   9  */
  10
  11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  12
  13 #include <linux/cpu.h>
  14 #include <linux/errno.h>
  15 #include <linux/device.h>
  16 #include <linux/of.h>
  17 #include <linux/pm_domain.h>
  18 #include <linux/slab.h>
  19 #include <linux/export.h>
  20 #include <linux/energy_model.h>
  21
  22 #include "opp.h"
  23
  24 /* OPP tables with uninitialized required OPPs, protected by opp_table_lock */
  25 static LIST_HEAD(lazy_opp_tables);
  26
  27 /*
  28  * Returns opp descriptor node for a device node, caller must
  29  * do of_node_put().
  30  */
  31 static struct device_node *_opp_of_get_opp_desc_node(struct device_node *np,
  32                                                      int index)
  33 {
  34         /* "operating-points-v2" can be an array for power domain providers */
  35         return of_parse_phandle(np, "operating-points-v2", index);
  36 }
  37
  38 /* Returns opp descriptor node for a device, caller must do of_node_put() */
  39 struct device_node *dev_pm_opp_of_get_opp_desc_node(struct device *dev)
  40 {
  41         return _opp_of_get_opp_desc_node(dev->of_node, 0);
  42 }
  43 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_opp_desc_node);
  44
  45 struct opp_table *_managed_opp(struct device *dev, int index)
  46 {
  47         struct opp_table *opp_table, *managed_table = NULL;
  48         struct device_node *np;
  49
  50         np = _opp_of_get_opp_desc_node(dev->of_node, index);
  51         if (!np)
  52                 return NULL;
  53
  54         list_for_each_entry(opp_table, &opp_tables, node) {
  55                 if (opp_table->np == np) {
  56                         /*
  57                          * Multiple devices can point to the same OPP table and
  58                          * so will have same node-pointer, np.
  59                          *
  60                          * But the OPPs will be considered as shared only if the
  61                          * OPP table contains a "opp-shared" property.
  62                          */
  63                         if (opp_table->shared_opp == OPP_TABLE_ACCESS_SHARED) {
  64                                 _get_opp_table_kref(opp_table);
  65                                 managed_table = opp_table;
  66                         }
  67
  68                         break;
  69                 }
  70         }
  71
  72         of_node_put(np);
  73
  74         return managed_table;
  75 }
  76
  77 /* The caller must call dev_pm_opp_put() after the OPP is used */
  78 static struct dev_pm_opp *_find_opp_of_np(struct opp_table *opp_table,
  79                                           struct device_node *opp_np)
  80 {
  81         struct dev_pm_opp *opp;
  82
  83         mutex_lock(&opp_table->lock);
  84
  85         list_for_each_entry(opp, &opp_table->opp_list, node) {
  86                 if (opp->np == opp_np) {
  87                         dev_pm_opp_get(opp);
  88                         mutex_unlock(&opp_table->lock);
  89                         return opp;
  90                 }
  91         }
  92
  93         mutex_unlock(&opp_table->lock);
  94
  95         return NULL;
  96 }
  97
  98 static struct device_node *of_parse_required_opp(struct device_node *np,
  99                                                  int index)
 100 {
 101         return of_parse_phandle(np, "required-opps", index);
 102 }
 103
 104 /* The caller must call dev_pm_opp_put_opp_table() after the table is used */
 105 static struct opp_table *_find_table_of_opp_np(struct device_node *opp_np)
 106 {
 107         struct opp_table *opp_table;
 108         struct device_node *opp_table_np;
 109
 110         opp_table_np = of_get_parent(opp_np);
 111         if (!opp_table_np)
 112                 goto err;
 113
 114         /* It is safe to put the node now as all we need now is its address */
 115         of_node_put(opp_table_np);
 116
 117         mutex_lock(&opp_table_lock);
 118         list_for_each_entry(opp_table, &opp_tables, node) {
 119                 if (opp_table_np == opp_table->np) {
 120                         _get_opp_table_kref(opp_table);
 121                         mutex_unlock(&opp_table_lock);
 122                         return opp_table;
 123                 }
 124         }
 125         mutex_unlock(&opp_table_lock);
 126
 127 err:
 128         return ERR_PTR(-ENODEV);
 129 }
 130
 131 /* Free resources previously acquired by _opp_table_alloc_required_tables() */
 132 static void _opp_table_free_required_tables(struct opp_table *opp_table)
 133 {
 134         struct opp_table **required_opp_tables = opp_table->required_opp_tables;
 135         int i;
 136
 137         if (!required_opp_tables)
 138                 return;
 139
 140         for (i = 0; i < opp_table->required_opp_count; i++) {
 141                 if (IS_ERR_OR_NULL(required_opp_tables[i]))
 142                         continue;
 143
 144                 dev_pm_opp_put_opp_table(required_opp_tables[i]);
 145         }
 146
 147         kfree(required_opp_tables);
 148
 149         opp_table->required_opp_count = 0;
 150         opp_table->required_opp_tables = NULL;
 151
 152         mutex_lock(&opp_table_lock);
 153         list_del(&opp_table->lazy);
 154         mutex_unlock(&opp_table_lock);
 155 }
 156
 157 /*
 158  * Populate all devices and opp tables which are part of "required-opps" list.
 159  * Checking only the first OPP node should be enough.
 160  */
 161 static void _opp_table_alloc_required_tables(struct opp_table *opp_table,
 162                                              struct device *dev,
 163                                              struct device_node *opp_np)
 164 {
 165         struct opp_table **required_opp_tables;
 166         struct device_node *required_np, *np;
 167         bool lazy = false;
 168         int count, i, size;
 169
 170         /* Traversing the first OPP node is all we need */
 171         np = of_get_next_available_child(opp_np, NULL);
 172         if (!np) {
 173                 dev_warn(dev, "Empty OPP table\n");
 174
 175                 return;
 176         }
 177
 178         count = of_count_phandle_with_args(np, "required-opps", NULL);
 179         if (count <= 0)
 180                 goto put_np;
 181
 182         size = sizeof(*required_opp_tables) + sizeof(*opp_table->required_devs);
 183         required_opp_tables = kcalloc(count, size, GFP_KERNEL);
 184         if (!required_opp_tables)
 185                 goto put_np;
 186
 187         opp_table->required_opp_tables = required_opp_tables;
 188         opp_table->required_devs = (void *)(required_opp_tables + count);
 189         opp_table->required_opp_count = count;
 190
 191         for (i = 0; i < count; i++) {
 192                 required_np = of_parse_required_opp(np, i);
 193                 if (!required_np)
 194                         goto free_required_tables;
 195
 196                 required_opp_tables[i] = _find_table_of_opp_np(required_np);
 197                 of_node_put(required_np);
 198
 199                 if (IS_ERR(required_opp_tables[i]))
 200                         lazy = true;
 201         }
 202
 203         /* Let's do the linking later on */
 204         if (lazy) {
 205                 /*
 206                  * The OPP table is not held while allocating the table, take it
 207                  * now to avoid corruption to the lazy_opp_tables list.
 208                  */
 209                 mutex_lock(&opp_table_lock);
 210                 list_add(&opp_table->lazy, &lazy_opp_tables);
 211                 mutex_unlock(&opp_table_lock);
 212         }
 213
 214         goto put_np;
 215
 216 free_required_tables:
 217         _opp_table_free_required_tables(opp_table);
 218 put_np:
 219         of_node_put(np);
 220 }
 221
 222 void _of_init_opp_table(struct opp_table *opp_table, struct device *dev,
 223                         int index)
 224 {
 225         struct device_node *np, *opp_np;
 226         u32 val;
 227
 228         /*
 229          * Only required for backward compatibility with v1 bindings, but isn't
 230          * harmful for other cases. And so we do it unconditionally.
 231          */
 232         np = of_node_get(dev->of_node);
 233         if (!np)
 234                 return;
 235
 236         if (!of_property_read_u32(np, "clock-latency", &val))
 237                 opp_table->clock_latency_ns_max = val;
 238         of_property_read_u32(np, "voltage-tolerance",
 239                              &opp_table->voltage_tolerance_v1);
 240
 241         if (of_property_present(np, "#power-domain-cells"))
 242                 opp_table->is_genpd = true;
 243
 244         /* Get OPP table node */
 245         opp_np = _opp_of_get_opp_desc_node(np, index);
 246         of_node_put(np);
 247
 248         if (!opp_np)
 249                 return;
 250
 251         if (of_property_read_bool(opp_np, "opp-shared"))
 252                 opp_table->shared_opp = OPP_TABLE_ACCESS_SHARED;
 253         else
 254                 opp_table->shared_opp = OPP_TABLE_ACCESS_EXCLUSIVE;
 255
 256         opp_table->np = opp_np;
 257
 258         _opp_table_alloc_required_tables(opp_table, dev, opp_np);
 259 }
 260
 261 void _of_clear_opp_table(struct opp_table *opp_table)
 262 {
 263         _opp_table_free_required_tables(opp_table);
 264         of_node_put(opp_table->np);
 265 }
 266
 267 /*
 268  * Release all resources previously acquired with a call to
 269  * _of_opp_alloc_required_opps().
 270  */
 271 static void _of_opp_free_required_opps(struct opp_table *opp_table,
 272                                        struct dev_pm_opp *opp)
 273 {
 274         struct dev_pm_opp **required_opps = opp->required_opps;
 275         int i;
 276
 277         if (!required_opps)
 278                 return;
 279
 280         for (i = 0; i < opp_table->required_opp_count; i++) {
 281                 if (!required_opps[i])
 282                         continue;
 283
 284                 /* Put the reference back */
 285                 dev_pm_opp_put(required_opps[i]);
 286         }
 287
 288         opp->required_opps = NULL;
 289         kfree(required_opps);
 290 }
 291
 292 void _of_clear_opp(struct opp_table *opp_table, struct dev_pm_opp *opp)
 293 {
 294         _of_opp_free_required_opps(opp_table, opp);
 295         of_node_put(opp->np);
 296 }
 297
 298 static int _link_required_opps(struct dev_pm_opp *opp, struct opp_table *opp_table,
 299                                struct opp_table *required_table, int index)
 300 {
 301         struct device_node *np;
 302
 303         np = of_parse_required_opp(opp->np, index);
 304         if (unlikely(!np))
 305                 return -ENODEV;
 306
 307         opp->required_opps[index] = _find_opp_of_np(required_table, np);
 308         of_node_put(np);
 309
 310         if (!opp->required_opps[index]) {
 311                 pr_err("%s: Unable to find required OPP node: %pOF (%d)\n",
 312                        __func__, opp->np, index);
 313                 return -ENODEV;
 314         }
 315
 316         /*
 317          * There are two genpd (as required-opp) cases that we need to handle,
 318          * devices with a single genpd and ones with multiple genpds.
 319          *
 320          * The single genpd case requires special handling as we need to use the
 321          * same `dev` structure (instead of a virtual one provided by genpd
 322          * core) for setting the performance state.
 323          *
 324          * It doesn't make sense for a device's DT entry to have both
 325          * "opp-level" and single "required-opps" entry pointing to a genpd's
 326          * OPP, as that would make the OPP core call
 327          * dev_pm_domain_set_performance_state() for two different values for
 328          * the same device structure. Lets treat single genpd configuration as a
 329          * case where the OPP's level is directly available without required-opp
 330          * link in the DT.
 331          *
 332          * Just update the `level` with the right value, which
 333          * dev_pm_opp_set_opp() will take care of in the normal path itself.
 334          *
 335          * There is another case though, where a genpd's OPP table has
 336          * required-opps set to a parent genpd. The OPP core expects the user to
 337          * set the respective required `struct device` pointer via
 338          * dev_pm_opp_set_config().
 339          */
 340         if (required_table->is_genpd && opp_table->required_opp_count == 1 &&
 341             !opp_table->required_devs[0]) {
 342                 if (!WARN_ON(opp->level != OPP_LEVEL_UNSET))
 343                         opp->level = opp->required_opps[0]->level;
 344         }
 345
 346         return 0;
 347 }
 348
 349 /* Populate all required OPPs which are part of "required-opps" list */
 350 static int _of_opp_alloc_required_opps(struct opp_table *opp_table,
 351                                        struct dev_pm_opp *opp)
 352 {
 353         struct opp_table *required_table;
 354         int i, ret, count = opp_table->required_opp_count;
 355
 356         if (!count)
 357                 return 0;
 358
 359         opp->required_opps = kcalloc(count, sizeof(*opp->required_opps), GFP_KERNEL);
 360         if (!opp->required_opps)
 361                 return -ENOMEM;
 362
 363         for (i = 0; i < count; i++) {
 364                 required_table = opp_table->required_opp_tables[i];
 365
 366                 /* Required table not added yet, we will link later */
 367                 if (IS_ERR_OR_NULL(required_table))
 368                         continue;
 369
 370                 ret = _link_required_opps(opp, opp_table, required_table, i);
 371                 if (ret)
 372                         goto free_required_opps;
 373         }
 374
 375         return 0;
 376
 377 free_required_opps:
 378         _of_opp_free_required_opps(opp_table, opp);
 379
 380         return ret;
 381 }
 382
 383 /* Link required OPPs for an individual OPP */
 384 static int lazy_link_required_opps(struct opp_table *opp_table,
 385                                    struct opp_table *new_table, int index)
 386 {
 387         struct dev_pm_opp *opp;
 388         int ret;
 389
 390         list_for_each_entry(opp, &opp_table->opp_list, node) {
 391                 ret = _link_required_opps(opp, opp_table, new_table, index);
 392                 if (ret)
 393                         return ret;
 394         }
 395
 396         return 0;
 397 }
 398
 399 /* Link required OPPs for all OPPs of the newly added OPP table */
 400 static void lazy_link_required_opp_table(struct opp_table *new_table)
 401 {
 402         struct opp_table *opp_table, *temp, **required_opp_tables;
 403         struct device_node *required_np, *opp_np, *required_table_np;
 404         struct dev_pm_opp *opp;
 405         int i, ret;
 406
 407         mutex_lock(&opp_table_lock);
 408
 409         list_for_each_entry_safe(opp_table, temp, &lazy_opp_tables, lazy) {
 410                 bool lazy = false;
 411
 412                 /* opp_np can't be invalid here */
 413                 opp_np = of_get_next_available_child(opp_table->np, NULL);
 414
 415                 for (i = 0; i < opp_table->required_opp_count; i++) {
 416                         required_opp_tables = opp_table->required_opp_tables;
 417
 418                         /* Required opp-table is already parsed */
 419                         if (!IS_ERR(required_opp_tables[i]))
 420                                 continue;
 421
 422                         /* required_np can't be invalid here */
 423                         required_np = of_parse_required_opp(opp_np, i);
 424                         required_table_np = of_get_parent(required_np);
 425
 426                         of_node_put(required_table_np);
 427                         of_node_put(required_np);
 428
 429                         /*
 430                          * Newly added table isn't the required opp-table for
 431                          * opp_table.
 432                          */
 433                         if (required_table_np != new_table->np) {
 434                                 lazy = true;
 435                                 continue;
 436                         }
 437
 438                         required_opp_tables[i] = new_table;
 439                         _get_opp_table_kref(new_table);
 440
 441                         /* Link OPPs now */
 442                         ret = lazy_link_required_opps(opp_table, new_table, i);
 443                         if (ret) {
 444                                 /* The OPPs will be marked unusable */
 445                                 lazy = false;
 446                                 break;
 447                         }
 448                 }
 449
 450                 of_node_put(opp_np);
 451
 452                 /* All required opp-tables found, remove from lazy list */
 453                 if (!lazy) {
 454                         list_del_init(&opp_table->lazy);
 455
 456                         list_for_each_entry(opp, &opp_table->opp_list, node)
 457                                 _required_opps_available(opp, opp_table->required_opp_count);
 458                 }
 459         }
 460
 461         mutex_unlock(&opp_table_lock);
 462 }
 463
 464 static int _bandwidth_supported(struct device *dev, struct opp_table *opp_table)
 465 {
 466         struct device_node *np, *opp_np;
 467         struct property *prop;
 468
 469         if (!opp_table) {
 470                 np = of_node_get(dev->of_node);
 471                 if (!np)
 472                         return -ENODEV;
 473
 474                 opp_np = _opp_of_get_opp_desc_node(np, 0);
 475                 of_node_put(np);
 476         } else {
 477                 opp_np = of_node_get(opp_table->np);
 478         }
 479
 480         /* Lets not fail in case we are parsing opp-v1 bindings */
 481         if (!opp_np)
 482                 return 0;
 483
 484         /* Checking only first OPP is sufficient */
 485         np = of_get_next_available_child(opp_np, NULL);
 486         of_node_put(opp_np);
 487         if (!np) {
 488                 dev_err(dev, "OPP table empty\n");
 489                 return -EINVAL;
 490         }
 491
 492         prop = of_find_property(np, "opp-peak-kBps", NULL);
 493         of_node_put(np);
 494
 495         if (!prop || !prop->length)
 496                 return 0;
 497
 498         return 1;
 499 }
 500
 501 int dev_pm_opp_of_find_icc_paths(struct device *dev,
 502                                  struct opp_table *opp_table)
 503 {
 504         struct device_node *np;
 505         int ret, i, count, num_paths;
 506         struct icc_path **paths;
 507
 508         ret = _bandwidth_supported(dev, opp_table);
 509         if (ret == -EINVAL)
 510                 return 0; /* Empty OPP table is a valid corner-case, let's not fail */
 511         else if (ret <= 0)
 512                 return ret;
 513
 514         ret = 0;
 515
 516         np = of_node_get(dev->of_node);
 517         if (!np)
 518                 return 0;
 519
 520         count = of_count_phandle_with_args(np, "interconnects",
 521                                            "#interconnect-cells");
 522         of_node_put(np);
 523         if (count < 0)
 524                 return 0;
 525
 526         /* two phandles when #interconnect-cells = <1> */
 527         if (count % 2) {
 528                 dev_err(dev, "%s: Invalid interconnects values\n", __func__);
 529                 return -EINVAL;
 530         }
 531
 532         num_paths = count / 2;
 533         paths = kcalloc(num_paths, sizeof(*paths), GFP_KERNEL);
 534         if (!paths)
 535                 return -ENOMEM;
 536
 537         for (i = 0; i < num_paths; i++) {
 538                 paths[i] = of_icc_get_by_index(dev, i);
 539                 if (IS_ERR(paths[i])) {
 540                         ret = dev_err_probe(dev, PTR_ERR(paths[i]), "%s: Unable to get path%d\n", __func__, i);
 541                         goto err;
 542                 }
 543         }
 544
 545         if (opp_table) {
 546                 opp_table->paths = paths;
 547                 opp_table->path_count = num_paths;
 548                 return 0;
 549         }
 550
 551 err:
 552         while (i--)
 553                 icc_put(paths[i]);
 554
 555         kfree(paths);
 556
 557         return ret;
 558 }
 559 EXPORT_SYMBOL_GPL(dev_pm_opp_of_find_icc_paths);
 560
 561 static bool _opp_is_supported(struct device *dev, struct opp_table *opp_table,
 562                               struct device_node *np)
 563 {
 564         unsigned int levels = opp_table->supported_hw_count;
 565         int count, versions, ret, i, j;
 566         u32 val;
 567
 568         if (!opp_table->supported_hw) {
 569                 /*
 570                  * In the case that no supported_hw has been set by the
 571                  * platform but there is an opp-supported-hw value set for
 572                  * an OPP then the OPP should not be enabled as there is
 573                  * no way to see if the hardware supports it.
 574                  */
 575                 if (of_property_present(np, "opp-supported-hw"))
 576                         return false;
 577                 else
 578                         return true;
 579         }
 580
 581         count = of_property_count_u32_elems(np, "opp-supported-hw");
 582         if (count <= 0 || count % levels) {
 583                 dev_err(dev, "%s: Invalid opp-supported-hw property (%d)\n",
 584                         __func__, count);
 585                 return false;
 586         }
 587
 588         versions = count / levels;
 589
 590         /* All levels in at least one of the versions should match */
 591         for (i = 0; i < versions; i++) {
 592                 bool supported = true;
 593
 594                 for (j = 0; j < levels; j++) {
 595                         ret = of_property_read_u32_index(np, "opp-supported-hw",
 596                                                          i * levels + j, &val);
 597                         if (ret) {
 598                                 dev_warn(dev, "%s: failed to read opp-supported-hw property at index %d: %d\n",
 599                                          __func__, i * levels + j, ret);
 600                                 return false;
 601                         }
 602
 603                         /* Check if the level is supported */
 604                         if (!(val & opp_table->supported_hw[j])) {
 605                                 supported = false;
 606                                 break;
 607                         }
 608                 }
 609
 610                 if (supported)
 611                         return true;
 612         }
 613
 614         return false;
 615 }
 616
 617 static u32 *_parse_named_prop(struct dev_pm_opp *opp, struct device *dev,
 618                               struct opp_table *opp_table,
 619                               const char *prop_type, bool *triplet)
 620 {
 621         struct property *prop = NULL;
 622         char name[NAME_MAX];
 623         int count, ret;
 624         u32 *out;
 625
 626         /* Search for "opp-<prop_type>-<name>" */
 627         if (opp_table->prop_name) {
 628                 snprintf(name, sizeof(name), "opp-%s-%s", prop_type,
 629                          opp_table->prop_name);
 630                 prop = of_find_property(opp->np, name, NULL);
 631         }
 632
 633         if (!prop) {
 634                 /* Search for "opp-<prop_type>" */
 635                 snprintf(name, sizeof(name), "opp-%s", prop_type);
 636                 prop = of_find_property(opp->np, name, NULL);
 637                 if (!prop)
 638                         return NULL;
 639         }
 640
 641         count = of_property_count_u32_elems(opp->np, name);
 642         if (count < 0) {
 643                 dev_err(dev, "%s: Invalid %s property (%d)\n", __func__, name,
 644                         count);
 645                 return ERR_PTR(count);
 646         }
 647
 648         /*
 649          * Initialize regulator_count, if regulator information isn't provided
 650          * by the platform. Now that one of the properties is available, fix the
 651          * regulator_count to 1.
 652          */
 653         if (unlikely(opp_table->regulator_count == -1))
 654                 opp_table->regulator_count = 1;
 655
 656         if (count != opp_table->regulator_count &&
 657             (!triplet || count != opp_table->regulator_count * 3)) {
 658                 dev_err(dev, "%s: Invalid number of elements in %s property (%u) with supplies (%d)\n",
 659                         __func__, prop_type, count, opp_table->regulator_count);
 660                 return ERR_PTR(-EINVAL);
 661         }
 662
 663         out = kmalloc_array(count, sizeof(*out), GFP_KERNEL);
 664         if (!out)
 665                 return ERR_PTR(-EINVAL);
 666
 667         ret = of_property_read_u32_array(opp->np, name, out, count);
 668         if (ret) {
 669                 dev_err(dev, "%s: error parsing %s: %d\n", __func__, name, ret);
 670                 kfree(out);
 671                 return ERR_PTR(-EINVAL);
 672         }
 673
 674         if (triplet)
 675                 *triplet = count != opp_table->regulator_count;
 676
 677         return out;
 678 }
 679
 680 static u32 *opp_parse_microvolt(struct dev_pm_opp *opp, struct device *dev,
 681                                 struct opp_table *opp_table, bool *triplet)
 682 {
 683         u32 *microvolt;
 684
 685         microvolt = _parse_named_prop(opp, dev, opp_table, "microvolt", triplet);
 686         if (IS_ERR(microvolt))
 687                 return microvolt;
 688
 689         if (!microvolt) {
 690                 /*
 691                  * Missing property isn't a problem, but an invalid
 692                  * entry is. This property isn't optional if regulator
 693                  * information is provided. Check only for the first OPP, as
 694                  * regulator_count may get initialized after that to a valid
 695                  * value.
 696                  */
 697                 if (list_empty(&opp_table->opp_list) &&
 698                     opp_table->regulator_count > 0) {
 699                         dev_err(dev, "%s: opp-microvolt missing although OPP managing regulators\n",
 700                                 __func__);
 701                         return ERR_PTR(-EINVAL);
 702                 }
 703         }
 704
 705         return microvolt;
 706 }
 707
 708 static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,
 709                               struct opp_table *opp_table)
 710 {
 711         u32 *microvolt, *microamp, *microwatt;
 712         int ret = 0, i, j;
 713         bool triplet;
 714
 715         microvolt = opp_parse_microvolt(opp, dev, opp_table, &triplet);
 716         if (IS_ERR(microvolt))
 717                 return PTR_ERR(microvolt);
 718
 719         microamp = _parse_named_prop(opp, dev, opp_table, "microamp", NULL);
 720         if (IS_ERR(microamp)) {
 721                 ret = PTR_ERR(microamp);
 722                 goto free_microvolt;
 723         }
 724
 725         microwatt = _parse_named_prop(opp, dev, opp_table, "microwatt", NULL);
 726         if (IS_ERR(microwatt)) {
 727                 ret = PTR_ERR(microwatt);
 728                 goto free_microamp;
 729         }
 730
 731         /*
 732          * Initialize regulator_count if it is uninitialized and no properties
 733          * are found.
 734          */
 735         if (unlikely(opp_table->regulator_count == -1)) {
 736                 opp_table->regulator_count = 0;
 737                 return 0;
 738         }
 739
 740         for (i = 0, j = 0; i < opp_table->regulator_count; i++) {
 741                 if (microvolt) {
 742                         opp->supplies[i].u_volt = microvolt[j++];
 743
 744                         if (triplet) {
 745                                 opp->supplies[i].u_volt_min = microvolt[j++];
 746                                 opp->supplies[i].u_volt_max = microvolt[j++];
 747                         } else {
 748                                 opp->supplies[i].u_volt_min = opp->supplies[i].u_volt;
 749                                 opp->supplies[i].u_volt_max = opp->supplies[i].u_volt;
 750                         }
 751                 }
 752
 753                 if (microamp)
 754                         opp->supplies[i].u_amp = microamp[i];
 755
 756                 if (microwatt)
 757                         opp->supplies[i].u_watt = microwatt[i];
 758         }
 759
 760         kfree(microwatt);
 761 free_microamp:
 762         kfree(microamp);
 763 free_microvolt:
 764         kfree(microvolt);
 765
 766         return ret;
 767 }
 768
 769 /**
 770  * dev_pm_opp_of_remove_table() - Free OPP table entries created from static DT
 771  *                                entries
 772  * @dev:        device pointer used to lookup OPP table.
 773  *
 774  * Free OPPs created using static entries present in DT.
 775  */
 776 void dev_pm_opp_of_remove_table(struct device *dev)
 777 {
 778         dev_pm_opp_remove_table(dev);
 779 }
 780 EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table);
 781
 782 static int _read_rate(struct dev_pm_opp *new_opp, struct opp_table *opp_table,
 783                       struct device_node *np)
 784 {
 785         struct property *prop;
 786         int i, count, ret;
 787         u64 *rates;
 788
 789         prop = of_find_property(np, "opp-hz", NULL);
 790         if (!prop)
 791                 return -ENODEV;
 792
 793         count = prop->length / sizeof(u64);
 794         if (opp_table->clk_count != count) {
 795                 pr_err("%s: Count mismatch between opp-hz and clk_count (%d %d)\n",
 796                        __func__, count, opp_table->clk_count);
 797                 return -EINVAL;
 798         }
 799
 800         rates = kmalloc_array(count, sizeof(*rates), GFP_KERNEL);
 801         if (!rates)
 802                 return -ENOMEM;
 803
 804         ret = of_property_read_u64_array(np, "opp-hz", rates, count);
 805         if (ret) {
 806                 pr_err("%s: Error parsing opp-hz: %d\n", __func__, ret);
 807         } else {
 808                 /*
 809                  * Rate is defined as an unsigned long in clk API, and so
 810                  * casting explicitly to its type. Must be fixed once rate is 64
 811                  * bit guaranteed in clk API.
 812                  */
 813                 for (i = 0; i < count; i++) {
 814                         new_opp->rates[i] = (unsigned long)rates[i];
 815
 816                         /* This will happen for frequencies > 4.29 GHz */
 817                         WARN_ON(new_opp->rates[i] != rates[i]);
 818                 }
 819         }
 820
 821         kfree(rates);
 822
 823         return ret;
 824 }
 825
 826 static int _read_bw(struct dev_pm_opp *new_opp, struct opp_table *opp_table,
 827                     struct device_node *np, bool peak)
 828 {
 829         const char *name = peak ? "opp-peak-kBps" : "opp-avg-kBps";
 830         struct property *prop;
 831         int i, count, ret;
 832         u32 *bw;
 833
 834         prop = of_find_property(np, name, NULL);
 835         if (!prop)
 836                 return -ENODEV;
 837
 838         count = prop->length / sizeof(u32);
 839         if (opp_table->path_count != count) {
 840                 pr_err("%s: Mismatch between %s and paths (%d %d)\n",
 841                                 __func__, name, count, opp_table->path_count);
 842                 return -EINVAL;
 843         }
 844
 845         bw = kmalloc_array(count, sizeof(*bw), GFP_KERNEL);
 846         if (!bw)
 847                 return -ENOMEM;
 848
 849         ret = of_property_read_u32_array(np, name, bw, count);
 850         if (ret) {
 851                 pr_err("%s: Error parsing %s: %d\n", __func__, name, ret);
 852                 goto out;
 853         }
 854
 855         for (i = 0; i < count; i++) {
 856                 if (peak)
 857                         new_opp->bandwidth[i].peak = kBps_to_icc(bw[i]);
 858                 else
 859                         new_opp->bandwidth[i].avg = kBps_to_icc(bw[i]);
 860         }
 861
 862 out:
 863         kfree(bw);
 864         return ret;
 865 }
 866
 867 static int _read_opp_key(struct dev_pm_opp *new_opp,
 868                          struct opp_table *opp_table, struct device_node *np)
 869 {
 870         bool found = false;
 871         int ret;
 872
 873         ret = _read_rate(new_opp, opp_table, np);
 874         if (!ret)
 875                 found = true;
 876         else if (ret != -ENODEV)
 877                 return ret;
 878
 879         /*
 880          * Bandwidth consists of peak and average (optional) values:
 881          * opp-peak-kBps = <path1_value path2_value>;
 882          * opp-avg-kBps = <path1_value path2_value>;
 883          */
 884         ret = _read_bw(new_opp, opp_table, np, true);
 885         if (!ret) {
 886                 found = true;
 887                 ret = _read_bw(new_opp, opp_table, np, false);
 888         }
 889
 890         /* The properties were found but we failed to parse them */
 891         if (ret && ret != -ENODEV)
 892                 return ret;
 893
 894         if (!of_property_read_u32(np, "opp-level", &new_opp->level))
 895                 found = true;
 896
 897         if (found)
 898                 return 0;
 899
 900         return ret;
 901 }
 902
 903 /**
 904  * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings)
 905  * @opp_table:  OPP table
 906  * @dev:        device for which we do this operation
 907  * @np:         device node
 908  *
 909  * This function adds an opp definition to the opp table and returns status. The
 910  * opp can be controlled using dev_pm_opp_enable/disable functions and may be
 911  * removed by dev_pm_opp_remove.
 912  *
 913  * Return:
 914  * Valid OPP pointer:
 915  *              On success
 916  * NULL:
 917  *              Duplicate OPPs (both freq and volt are same) and opp->available
 918  *              OR if the OPP is not supported by hardware.
 919  * ERR_PTR(-EEXIST):
 920  *              Freq are same and volt are different OR
 921  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 922  * ERR_PTR(-ENOMEM):
 923  *              Memory allocation failure
 924  * ERR_PTR(-EINVAL):
 925  *              Failed parsing the OPP node
 926  */
 927 static struct dev_pm_opp *_opp_add_static_v2(struct opp_table *opp_table,
 928                 struct device *dev, struct device_node *np)
 929 {
 930         struct dev_pm_opp *new_opp;
 931         u32 val;
 932         int ret;
 933
 934         new_opp = _opp_allocate(opp_table);
 935         if (!new_opp)
 936                 return ERR_PTR(-ENOMEM);
 937
 938         ret = _read_opp_key(new_opp, opp_table, np);
 939         if (ret < 0) {
 940                 dev_err(dev, "%s: opp key field not found\n", __func__);
 941                 goto free_opp;
 942         }
 943
 944         /* Check if the OPP supports hardware's hierarchy of versions or not */
 945         if (!_opp_is_supported(dev, opp_table, np)) {
 946                 dev_dbg(dev, "OPP not supported by hardware: %s\n",
 947                         of_node_full_name(np));
 948                 goto free_opp;
 949         }
 950
 951         new_opp->turbo = of_property_read_bool(np, "turbo-mode");
 952
 953         new_opp->np = of_node_get(np);
 954         new_opp->dynamic = false;
 955         new_opp->available = true;
 956
 957         ret = _of_opp_alloc_required_opps(opp_table, new_opp);
 958         if (ret)
 959                 goto free_opp;
 960
 961         if (!of_property_read_u32(np, "clock-latency-ns", &val))
 962                 new_opp->clock_latency_ns = val;
 963
 964         ret = opp_parse_supplies(new_opp, dev, opp_table);
 965         if (ret)
 966                 goto free_required_opps;
 967
 968         ret = _opp_add(dev, new_opp, opp_table);
 969         if (ret) {
 970                 /* Don't return error for duplicate OPPs */
 971                 if (ret == -EBUSY)
 972                         ret = 0;
 973                 goto free_required_opps;
 974         }
 975
 976         /* OPP to select on device suspend */
 977         if (of_property_read_bool(np, "opp-suspend")) {
 978                 if (opp_table->suspend_opp) {
 979                         /* Pick the OPP with higher rate/bw/level as suspend OPP */
 980                         if (_opp_compare_key(opp_table, new_opp, opp_table->suspend_opp) == 1) {
 981                                 opp_table->suspend_opp->suspend = false;
 982                                 new_opp->suspend = true;
 983                                 opp_table->suspend_opp = new_opp;
 984                         }
 985                 } else {
 986                         new_opp->suspend = true;
 987                         opp_table->suspend_opp = new_opp;
 988                 }
 989         }
 990
 991         if (new_opp->clock_latency_ns > opp_table->clock_latency_ns_max)
 992                 opp_table->clock_latency_ns_max = new_opp->clock_latency_ns;
 993
 994         pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu level:%u\n",
 995                  __func__, new_opp->turbo, new_opp->rates[0],
 996                  new_opp->supplies[0].u_volt, new_opp->supplies[0].u_volt_min,
 997                  new_opp->supplies[0].u_volt_max, new_opp->clock_latency_ns,
 998                  new_opp->level);
 999
1000         /*
1001          * Notify the changes in the availability of the operable
1002          * frequency/voltage list.
1003          */
1004         blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ADD, new_opp);
1005         return new_opp;
1006
1007 free_required_opps:
1008         _of_opp_free_required_opps(opp_table, new_opp);
1009 free_opp:
1010         _opp_free(new_opp);
1011
1012         return ret ? ERR_PTR(ret) : NULL;
1013 }
1014
1015 /* Initializes OPP tables based on new bindings */
1016 static int _of_add_opp_table_v2(struct device *dev, struct opp_table *opp_table)
1017 {
1018         struct device_node *np;
1019         int ret, count = 0;
1020         struct dev_pm_opp *opp;
1021
1022         /* OPP table is already initialized for the device */
1023         mutex_lock(&opp_table->lock);
1024         if (opp_table->parsed_static_opps) {
1025                 opp_table->parsed_static_opps++;
1026                 mutex_unlock(&opp_table->lock);
1027                 return 0;
1028         }
1029
1030         opp_table->parsed_static_opps = 1;
1031         mutex_unlock(&opp_table->lock);
1032
1033         /* We have opp-table node now, iterate over it and add OPPs */
1034         for_each_available_child_of_node(opp_table->np, np) {
1035                 opp = _opp_add_static_v2(opp_table, dev, np);
1036                 if (IS_ERR(opp)) {
1037                         ret = PTR_ERR(opp);
1038                         dev_err(dev, "%s: Failed to add OPP, %d\n", __func__,
1039                                 ret);
1040                         of_node_put(np);
1041                         goto remove_static_opp;
1042                 } else if (opp) {
1043                         count++;
1044                 }
1045         }
1046
1047         /* There should be one or more OPPs defined */
1048         if (!count) {
1049                 dev_err(dev, "%s: no supported OPPs", __func__);
1050                 ret = -ENOENT;
1051                 goto remove_static_opp;
1052         }
1053
1054         lazy_link_required_opp_table(opp_table);
1055
1056         return 0;
1057
1058 remove_static_opp:
1059         _opp_remove_all_static(opp_table);
1060
1061         return ret;
1062 }
1063
1064 /* Initializes OPP tables based on old-deprecated bindings */
1065 static int _of_add_opp_table_v1(struct device *dev, struct opp_table *opp_table)
1066 {
1067         const struct property *prop;
1068         const __be32 *val;
1069         int nr, ret = 0;
1070
1071         mutex_lock(&opp_table->lock);
1072         if (opp_table->parsed_static_opps) {
1073                 opp_table->parsed_static_opps++;
1074                 mutex_unlock(&opp_table->lock);
1075                 return 0;
1076         }
1077
1078         opp_table->parsed_static_opps = 1;
1079         mutex_unlock(&opp_table->lock);
1080
1081         prop = of_find_property(dev->of_node, "operating-points", NULL);
1082         if (!prop) {
1083                 ret = -ENODEV;
1084                 goto remove_static_opp;
1085         }
1086         if (!prop->value) {
1087                 ret = -ENODATA;
1088                 goto remove_static_opp;
1089         }
1090
1091         /*
1092          * Each OPP is a set of tuples consisting of frequency and
1093          * voltage like <freq-kHz vol-uV>.
1094          */
1095         nr = prop->length / sizeof(u32);
1096         if (nr % 2) {
1097                 dev_err(dev, "%s: Invalid OPP table\n", __func__);
1098                 ret = -EINVAL;
1099                 goto remove_static_opp;
1100         }
1101
1102         val = prop->value;
1103         while (nr) {
1104                 unsigned long freq = be32_to_cpup(val++) * 1000;
1105                 unsigned long volt = be32_to_cpup(val++);
1106                 struct dev_pm_opp_data data = {
1107                         .freq = freq,
1108                         .u_volt = volt,
1109                 };
1110
1111                 ret = _opp_add_v1(opp_table, dev, &data, false);
1112                 if (ret) {
1113                         dev_err(dev, "%s: Failed to add OPP %ld (%d)\n",
1114                                 __func__, data.freq, ret);
1115                         goto remove_static_opp;
1116                 }
1117                 nr -= 2;
1118         }
1119
1120         return 0;
1121
1122 remove_static_opp:
1123         _opp_remove_all_static(opp_table);
1124
1125         return ret;
1126 }
1127
1128 static int _of_add_table_indexed(struct device *dev, int index)
1129 {
1130         struct opp_table *opp_table;
1131         int ret, count;
1132
1133         if (index) {
1134                 /*
1135                  * If only one phandle is present, then the same OPP table
1136                  * applies for all index requests.
1137                  */
1138                 count = of_count_phandle_with_args(dev->of_node,
1139                                                    "operating-points-v2", NULL);
1140                 if (count == 1)
1141                         index = 0;
1142         }
1143
1144         opp_table = _add_opp_table_indexed(dev, index, true);
1145         if (IS_ERR(opp_table))
1146                 return PTR_ERR(opp_table);
1147
1148         /*
1149          * OPPs have two version of bindings now. Also try the old (v1)
1150          * bindings for backward compatibility with older dtbs.
1151          */
1152         if (opp_table->np)
1153                 ret = _of_add_opp_table_v2(dev, opp_table);
1154         else
1155                 ret = _of_add_opp_table_v1(dev, opp_table);
1156
1157         if (ret)
1158                 dev_pm_opp_put_opp_table(opp_table);
1159
1160         return ret;
1161 }
1162
1163 static void devm_pm_opp_of_table_release(void *data)
1164 {
1165         dev_pm_opp_of_remove_table(data);
1166 }
1167
1168 static int _devm_of_add_table_indexed(struct device *dev, int index)
1169 {
1170         int ret;
1171
1172         ret = _of_add_table_indexed(dev, index);
1173         if (ret)
1174                 return ret;
1175
1176         return devm_add_action_or_reset(dev, devm_pm_opp_of_table_release, dev);
1177 }
1178
1179 /**
1180  * devm_pm_opp_of_add_table() - Initialize opp table from device tree
1181  * @dev:        device pointer used to lookup OPP table.
1182  *
1183  * Register the initial OPP table with the OPP library for given device.
1184  *
1185  * The opp_table structure will be freed after the device is destroyed.
1186  *
1187  * Return:
1188  * 0            On success OR
1189  *              Duplicate OPPs (both freq and volt are same) and opp->available
1190  * -EEXIST      Freq are same and volt are different OR
1191  *              Duplicate OPPs (both freq and volt are same) and !opp->available
1192  * -ENOMEM      Memory allocation failure
1193  * -ENODEV      when 'operating-points' property is not found or is invalid data
1194  *              in device node.
1195  * -ENODATA     when empty 'operating-points' property is found
1196  * -EINVAL      when invalid entries are found in opp-v2 table
1197  */
1198 int devm_pm_opp_of_add_table(struct device *dev)
1199 {
1200         return _devm_of_add_table_indexed(dev, 0);
1201 }
1202 EXPORT_SYMBOL_GPL(devm_pm_opp_of_add_table);
1203
1204 /**
1205  * dev_pm_opp_of_add_table() - Initialize opp table from device tree
1206  * @dev:        device pointer used to lookup OPP table.
1207  *
1208  * Register the initial OPP table with the OPP library for given device.
1209  *
1210  * Return:
1211  * 0            On success OR
1212  *              Duplicate OPPs (both freq and volt are same) and opp->available
1213  * -EEXIST      Freq are same and volt are different OR
1214  *              Duplicate OPPs (both freq and volt are same) and !opp->available
1215  * -ENOMEM      Memory allocation failure
1216  * -ENODEV      when 'operating-points' property is not found or is invalid data
1217  *              in device node.
1218  * -ENODATA     when empty 'operating-points' property is found
1219  * -EINVAL      when invalid entries are found in opp-v2 table
1220  */
1221 int dev_pm_opp_of_add_table(struct device *dev)
1222 {
1223         return _of_add_table_indexed(dev, 0);
1224 }
1225 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table);
1226
1227 /**
1228  * dev_pm_opp_of_add_table_indexed() - Initialize indexed opp table from device tree
1229  * @dev:        device pointer used to lookup OPP table.
1230  * @index:      Index number.
1231  *
1232  * Register the initial OPP table with the OPP library for given device only
1233  * using the "operating-points-v2" property.
1234  *
1235  * Return: Refer to dev_pm_opp_of_add_table() for return values.
1236  */
1237 int dev_pm_opp_of_add_table_indexed(struct device *dev, int index)
1238 {
1239         return _of_add_table_indexed(dev, index);
1240 }
1241 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table_indexed);
1242
1243 /**
1244  * devm_pm_opp_of_add_table_indexed() - Initialize indexed opp table from device tree
1245  * @dev:        device pointer used to lookup OPP table.
1246  * @index:      Index number.
1247  *
1248  * This is a resource-managed variant of dev_pm_opp_of_add_table_indexed().
1249  */
1250 int devm_pm_opp_of_add_table_indexed(struct device *dev, int index)
1251 {
1252         return _devm_of_add_table_indexed(dev, index);
1253 }
1254 EXPORT_SYMBOL_GPL(devm_pm_opp_of_add_table_indexed);
1255
1256 /* CPU device specific helpers */
1257
1258 /**
1259  * dev_pm_opp_of_cpumask_remove_table() - Removes OPP table for @cpumask
1260  * @cpumask:    cpumask for which OPP table needs to be removed
1261  *
1262  * This removes the OPP tables for CPUs present in the @cpumask.
1263  * This should be used only to remove static entries created from DT.
1264  */
1265 void dev_pm_opp_of_cpumask_remove_table(const struct cpumask *cpumask)
1266 {
1267         _dev_pm_opp_cpumask_remove_table(cpumask, -1);
1268 }
1269 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_remove_table);
1270
1271 /**
1272  * dev_pm_opp_of_cpumask_add_table() - Adds OPP table for @cpumask
1273  * @cpumask:    cpumask for which OPP table needs to be added.
1274  *
1275  * This adds the OPP tables for CPUs present in the @cpumask.
1276  */
1277 int dev_pm_opp_of_cpumask_add_table(const struct cpumask *cpumask)
1278 {
1279         struct device *cpu_dev;
1280         int cpu, ret;
1281
1282         if (WARN_ON(cpumask_empty(cpumask)))
1283                 return -ENODEV;
1284
1285         for_each_cpu(cpu, cpumask) {
1286                 cpu_dev = get_cpu_device(cpu);
1287                 if (!cpu_dev) {
1288                         pr_err("%s: failed to get cpu%d device\n", __func__,
1289                                cpu);
1290                         ret = -ENODEV;
1291                         goto remove_table;
1292                 }
1293
1294                 ret = dev_pm_opp_of_add_table(cpu_dev);
1295                 if (ret) {
1296                         /*
1297                          * OPP may get registered dynamically, don't print error
1298                          * message here.
1299                          */
1300                         pr_debug("%s: couldn't find opp table for cpu:%d, %d\n",
1301                                  __func__, cpu, ret);
1302
1303                         goto remove_table;
1304                 }
1305         }
1306
1307         return 0;
1308
1309 remove_table:
1310         /* Free all other OPPs */
1311         _dev_pm_opp_cpumask_remove_table(cpumask, cpu);
1312
1313         return ret;
1314 }
1315 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_add_table);
1316
1317 /*
1318  * Works only for OPP v2 bindings.
1319  *
1320  * Returns -ENOENT if operating-points-v2 bindings aren't supported.
1321  */
1322 /**
1323  * dev_pm_opp_of_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with
1324  *                                    @cpu_dev using operating-points-v2
1325  *                                    bindings.
1326  *
1327  * @cpu_dev:    CPU device for which we do this operation
1328  * @cpumask:    cpumask to update with information of sharing CPUs
1329  *
1330  * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev.
1331  *
1332  * Returns -ENOENT if operating-points-v2 isn't present for @cpu_dev.
1333  */
1334 int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev,
1335                                    struct cpumask *cpumask)
1336 {
1337         struct device_node *np, *tmp_np, *cpu_np;
1338         int cpu, ret = 0;
1339
1340         /* Get OPP descriptor node */
1341         np = dev_pm_opp_of_get_opp_desc_node(cpu_dev);
1342         if (!np) {
1343                 dev_dbg(cpu_dev, "%s: Couldn't find opp node.\n", __func__);
1344                 return -ENOENT;
1345         }
1346
1347         cpumask_set_cpu(cpu_dev->id, cpumask);
1348
1349         /* OPPs are shared ? */
1350         if (!of_property_read_bool(np, "opp-shared"))
1351                 goto put_cpu_node;
1352
1353         for_each_possible_cpu(cpu) {
1354                 if (cpu == cpu_dev->id)
1355                         continue;
1356
1357                 cpu_np = of_cpu_device_node_get(cpu);
1358                 if (!cpu_np) {
1359                         dev_err(cpu_dev, "%s: failed to get cpu%d node\n",
1360                                 __func__, cpu);
1361                         ret = -ENOENT;
1362                         goto put_cpu_node;
1363                 }
1364
1365                 /* Get OPP descriptor node */
1366                 tmp_np = _opp_of_get_opp_desc_node(cpu_np, 0);
1367                 of_node_put(cpu_np);
1368                 if (!tmp_np) {
1369                         pr_err("%pOF: Couldn't find opp node\n", cpu_np);
1370                         ret = -ENOENT;
1371                         goto put_cpu_node;
1372                 }
1373
1374                 /* CPUs are sharing opp node */
1375                 if (np == tmp_np)
1376                         cpumask_set_cpu(cpu, cpumask);
1377
1378                 of_node_put(tmp_np);
1379         }
1380
1381 put_cpu_node:
1382         of_node_put(np);
1383         return ret;
1384 }
1385 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus);
1386
1387 /**
1388  * of_get_required_opp_performance_state() - Search for required OPP and return its performance state.
1389  * @np: Node that contains the "required-opps" property.
1390  * @index: Index of the phandle to parse.
1391  *
1392  * Returns the performance state of the OPP pointed out by the "required-opps"
1393  * property at @index in @np.
1394  *
1395  * Return: Zero or positive performance state on success, otherwise negative
1396  * value on errors.
1397  */
1398 int of_get_required_opp_performance_state(struct device_node *np, int index)
1399 {
1400         struct dev_pm_opp *opp;
1401         struct device_node *required_np;
1402         struct opp_table *opp_table;
1403         int pstate = -EINVAL;
1404
1405         required_np = of_parse_required_opp(np, index);
1406         if (!required_np)
1407                 return -ENODEV;
1408
1409         opp_table = _find_table_of_opp_np(required_np);
1410         if (IS_ERR(opp_table)) {
1411                 pr_err("%s: Failed to find required OPP table %pOF: %ld\n",
1412                        __func__, np, PTR_ERR(opp_table));
1413                 goto put_required_np;
1414         }
1415
1416         /* The OPP tables must belong to a genpd */
1417         if (unlikely(!opp_table->is_genpd)) {
1418                 pr_err("%s: Performance state is only valid for genpds.\n", __func__);
1419                 goto put_required_np;
1420         }
1421
1422         opp = _find_opp_of_np(opp_table, required_np);
1423         if (opp) {
1424                 if (opp->level == OPP_LEVEL_UNSET) {
1425                         pr_err("%s: OPP levels aren't available for %pOF\n",
1426                                __func__, np);
1427                 } else {
1428                         pstate = opp->level;
1429                 }
1430                 dev_pm_opp_put(opp);
1431
1432         }
1433
1434         dev_pm_opp_put_opp_table(opp_table);
1435
1436 put_required_np:
1437         of_node_put(required_np);
1438
1439         return pstate;
1440 }
1441 EXPORT_SYMBOL_GPL(of_get_required_opp_performance_state);
1442
1443 /**
1444  * dev_pm_opp_get_of_node() - Gets the DT node corresponding to an opp
1445  * @opp:        opp for which DT node has to be returned for
1446  *
1447  * Return: DT node corresponding to the opp, else 0 on success.
1448  *
1449  * The caller needs to put the node with of_node_put() after using it.
1450  */
1451 struct device_node *dev_pm_opp_get_of_node(struct dev_pm_opp *opp)
1452 {
1453         if (IS_ERR_OR_NULL(opp)) {
1454                 pr_err("%s: Invalid parameters\n", __func__);
1455                 return NULL;
1456         }
1457
1458         return of_node_get(opp->np);
1459 }
1460 EXPORT_SYMBOL_GPL(dev_pm_opp_get_of_node);
1461
1462 /*
1463  * Callback function provided to the Energy Model framework upon registration.
1464  * It provides the power used by @dev at @kHz if it is the frequency of an
1465  * existing OPP, or at the frequency of the first OPP above @kHz otherwise
1466  * (see dev_pm_opp_find_freq_ceil()). This function updates @kHz to the ceiled
1467  * frequency and @uW to the associated power.
1468  *
1469  * Returns 0 on success or a proper -EINVAL value in case of error.
1470  */
1471 static int __maybe_unused
1472 _get_dt_power(struct device *dev, unsigned long *uW, unsigned long *kHz)
1473 {
1474         struct dev_pm_opp *opp;
1475         unsigned long opp_freq, opp_power;
1476
1477         /* Find the right frequency and related OPP */
1478         opp_freq = *kHz * 1000;
1479         opp = dev_pm_opp_find_freq_ceil(dev, &opp_freq);
1480         if (IS_ERR(opp))
1481                 return -EINVAL;
1482
1483         opp_power = dev_pm_opp_get_power(opp);
1484         dev_pm_opp_put(opp);
1485         if (!opp_power)
1486                 return -EINVAL;
1487
1488         *kHz = opp_freq / 1000;
1489         *uW = opp_power;
1490
1491         return 0;
1492 }
1493
1494 /*
1495  * Callback function provided to the Energy Model framework upon registration.
1496  * This computes the power estimated by @dev at @kHz if it is the frequency
1497  * of an existing OPP, or at the frequency of the first OPP above @kHz otherwise
1498  * (see dev_pm_opp_find_freq_ceil()). This function updates @kHz to the ceiled
1499  * frequency and @uW to the associated power. The power is estimated as
1500  * P = C * V^2 * f with C being the device's capacitance and V and f
1501  * respectively the voltage and frequency of the OPP.
1502  *
1503  * Returns -EINVAL if the power calculation failed because of missing
1504  * parameters, 0 otherwise.
1505  */
1506 static int __maybe_unused _get_power(struct device *dev, unsigned long *uW,
1507                                      unsigned long *kHz)
1508 {
1509         struct dev_pm_opp *opp;
1510         struct device_node *np;
1511         unsigned long mV, Hz;
1512         u32 cap;
1513         u64 tmp;
1514         int ret;
1515
1516         np = of_node_get(dev->of_node);
1517         if (!np)
1518                 return -EINVAL;
1519
1520         ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1521         of_node_put(np);
1522         if (ret)
1523                 return -EINVAL;
1524
1525         Hz = *kHz * 1000;
1526         opp = dev_pm_opp_find_freq_ceil(dev, &Hz);
1527         if (IS_ERR(opp))
1528                 return -EINVAL;
1529
1530         mV = dev_pm_opp_get_voltage(opp) / 1000;
1531         dev_pm_opp_put(opp);
1532         if (!mV)
1533                 return -EINVAL;
1534
1535         tmp = (u64)cap * mV * mV * (Hz / 1000000);
1536         /* Provide power in micro-Watts */
1537         do_div(tmp, 1000000);
1538
1539         *uW = (unsigned long)tmp;
1540         *kHz = Hz / 1000;
1541
1542         return 0;
1543 }
1544
1545 static bool _of_has_opp_microwatt_property(struct device *dev)
1546 {
1547         unsigned long power, freq = 0;
1548         struct dev_pm_opp *opp;
1549
1550         /* Check if at least one OPP has needed property */
1551         opp = dev_pm_opp_find_freq_ceil(dev, &freq);
1552         if (IS_ERR(opp))
1553                 return false;
1554
1555         power = dev_pm_opp_get_power(opp);
1556         dev_pm_opp_put(opp);
1557         if (!power)
1558                 return false;
1559
1560         return true;
1561 }
1562
1563 /**
1564  * dev_pm_opp_of_register_em() - Attempt to register an Energy Model
1565  * @dev         : Device for which an Energy Model has to be registered
1566  * @cpus        : CPUs for which an Energy Model has to be registered. For
1567  *              other type of devices it should be set to NULL.
1568  *
1569  * This checks whether the "dynamic-power-coefficient" devicetree property has
1570  * been specified, and tries to register an Energy Model with it if it has.
1571  * Having this property means the voltages are known for OPPs and the EM
1572  * might be calculated.
1573  */
1574 int dev_pm_opp_of_register_em(struct device *dev, struct cpumask *cpus)
1575 {
1576         struct em_data_callback em_cb;
1577         struct device_node *np;
1578         int ret, nr_opp;
1579         u32 cap;
1580
1581         if (IS_ERR_OR_NULL(dev)) {
1582                 ret = -EINVAL;
1583                 goto failed;
1584         }
1585
1586         nr_opp = dev_pm_opp_get_opp_count(dev);
1587         if (nr_opp <= 0) {
1588                 ret = -EINVAL;
1589                 goto failed;
1590         }
1591
1592         /* First, try to find more precised Energy Model in DT */
1593         if (_of_has_opp_microwatt_property(dev)) {
1594                 EM_SET_ACTIVE_POWER_CB(em_cb, _get_dt_power);
1595                 goto register_em;
1596         }
1597
1598         np = of_node_get(dev->of_node);
1599         if (!np) {
1600                 ret = -EINVAL;
1601                 goto failed;
1602         }
1603
1604         /*
1605          * Register an EM only if the 'dynamic-power-coefficient' property is
1606          * set in devicetree. It is assumed the voltage values are known if that
1607          * property is set since it is useless otherwise. If voltages are not
1608          * known, just let the EM registration fail with an error to alert the
1609          * user about the inconsistent configuration.
1610          */
1611         ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1612         of_node_put(np);
1613         if (ret || !cap) {
1614                 dev_dbg(dev, "Couldn't find proper 'dynamic-power-coefficient' in DT\n");
1615                 ret = -EINVAL;
1616                 goto failed;
1617         }
1618
1619         EM_SET_ACTIVE_POWER_CB(em_cb, _get_power);
1620
1621 register_em:
1622         ret = em_dev_register_perf_domain(dev, nr_opp, &em_cb, cpus, true);
1623         if (ret)
1624                 goto failed;
1625
1626         return 0;
1627
1628 failed:
1629         dev_dbg(dev, "Couldn't register Energy Model %d\n", ret);
1630         return ret;
1631 }
1632 EXPORT_SYMBOL_GPL(dev_pm_opp_of_register_em);