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,
 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         return 0;
 317 }
 318
 319 /* Populate all required OPPs which are part of "required-opps" list */
 320 static int _of_opp_alloc_required_opps(struct opp_table *opp_table,
 321                                        struct dev_pm_opp *opp)
 322 {
 323         struct opp_table *required_table;
 324         int i, ret, count = opp_table->required_opp_count;
 325
 326         if (!count)
 327                 return 0;
 328
 329         opp->required_opps = kcalloc(count, sizeof(*opp->required_opps), GFP_KERNEL);
 330         if (!opp->required_opps)
 331                 return -ENOMEM;
 332
 333         for (i = 0; i < count; i++) {
 334                 required_table = opp_table->required_opp_tables[i];
 335
 336                 /* Required table not added yet, we will link later */
 337                 if (IS_ERR_OR_NULL(required_table))
 338                         continue;
 339
 340                 ret = _link_required_opps(opp, required_table, i);
 341                 if (ret)
 342                         goto free_required_opps;
 343         }
 344
 345         return 0;
 346
 347 free_required_opps:
 348         _of_opp_free_required_opps(opp_table, opp);
 349
 350         return ret;
 351 }
 352
 353 /* Link required OPPs for an individual OPP */
 354 static int lazy_link_required_opps(struct opp_table *opp_table,
 355                                    struct opp_table *new_table, int index)
 356 {
 357         struct dev_pm_opp *opp;
 358         int ret;
 359
 360         list_for_each_entry(opp, &opp_table->opp_list, node) {
 361                 ret = _link_required_opps(opp, new_table, index);
 362                 if (ret)
 363                         return ret;
 364         }
 365
 366         return 0;
 367 }
 368
 369 /* Link required OPPs for all OPPs of the newly added OPP table */
 370 static void lazy_link_required_opp_table(struct opp_table *new_table)
 371 {
 372         struct opp_table *opp_table, *temp, **required_opp_tables;
 373         struct device_node *required_np, *opp_np, *required_table_np;
 374         struct dev_pm_opp *opp;
 375         int i, ret;
 376
 377         mutex_lock(&opp_table_lock);
 378
 379         list_for_each_entry_safe(opp_table, temp, &lazy_opp_tables, lazy) {
 380                 bool lazy = false;
 381
 382                 /* opp_np can't be invalid here */
 383                 opp_np = of_get_next_available_child(opp_table->np, NULL);
 384
 385                 for (i = 0; i < opp_table->required_opp_count; i++) {
 386                         required_opp_tables = opp_table->required_opp_tables;
 387
 388                         /* Required opp-table is already parsed */
 389                         if (!IS_ERR(required_opp_tables[i]))
 390                                 continue;
 391
 392                         /* required_np can't be invalid here */
 393                         required_np = of_parse_required_opp(opp_np, i);
 394                         required_table_np = of_get_parent(required_np);
 395
 396                         of_node_put(required_table_np);
 397                         of_node_put(required_np);
 398
 399                         /*
 400                          * Newly added table isn't the required opp-table for
 401                          * opp_table.
 402                          */
 403                         if (required_table_np != new_table->np) {
 404                                 lazy = true;
 405                                 continue;
 406                         }
 407
 408                         required_opp_tables[i] = new_table;
 409                         _get_opp_table_kref(new_table);
 410
 411                         /* Link OPPs now */
 412                         ret = lazy_link_required_opps(opp_table, new_table, i);
 413                         if (ret) {
 414                                 /* The OPPs will be marked unusable */
 415                                 lazy = false;
 416                                 break;
 417                         }
 418                 }
 419
 420                 of_node_put(opp_np);
 421
 422                 /* All required opp-tables found, remove from lazy list */
 423                 if (!lazy) {
 424                         list_del_init(&opp_table->lazy);
 425
 426                         list_for_each_entry(opp, &opp_table->opp_list, node)
 427                                 _required_opps_available(opp, opp_table->required_opp_count);
 428                 }
 429         }
 430
 431         mutex_unlock(&opp_table_lock);
 432 }
 433
 434 static int _bandwidth_supported(struct device *dev, struct opp_table *opp_table)
 435 {
 436         struct device_node *np, *opp_np;
 437         struct property *prop;
 438
 439         if (!opp_table) {
 440                 np = of_node_get(dev->of_node);
 441                 if (!np)
 442                         return -ENODEV;
 443
 444                 opp_np = _opp_of_get_opp_desc_node(np, 0);
 445                 of_node_put(np);
 446         } else {
 447                 opp_np = of_node_get(opp_table->np);
 448         }
 449
 450         /* Lets not fail in case we are parsing opp-v1 bindings */
 451         if (!opp_np)
 452                 return 0;
 453
 454         /* Checking only first OPP is sufficient */
 455         np = of_get_next_available_child(opp_np, NULL);
 456         of_node_put(opp_np);
 457         if (!np) {
 458                 dev_err(dev, "OPP table empty\n");
 459                 return -EINVAL;
 460         }
 461
 462         prop = of_find_property(np, "opp-peak-kBps", NULL);
 463         of_node_put(np);
 464
 465         if (!prop || !prop->length)
 466                 return 0;
 467
 468         return 1;
 469 }
 470
 471 int dev_pm_opp_of_find_icc_paths(struct device *dev,
 472                                  struct opp_table *opp_table)
 473 {
 474         struct device_node *np;
 475         int ret, i, count, num_paths;
 476         struct icc_path **paths;
 477
 478         ret = _bandwidth_supported(dev, opp_table);
 479         if (ret == -EINVAL)
 480                 return 0; /* Empty OPP table is a valid corner-case, let's not fail */
 481         else if (ret <= 0)
 482                 return ret;
 483
 484         ret = 0;
 485
 486         np = of_node_get(dev->of_node);
 487         if (!np)
 488                 return 0;
 489
 490         count = of_count_phandle_with_args(np, "interconnects",
 491                                            "#interconnect-cells");
 492         of_node_put(np);
 493         if (count < 0)
 494                 return 0;
 495
 496         /* two phandles when #interconnect-cells = <1> */
 497         if (count % 2) {
 498                 dev_err(dev, "%s: Invalid interconnects values\n", __func__);
 499                 return -EINVAL;
 500         }
 501
 502         num_paths = count / 2;
 503         paths = kcalloc(num_paths, sizeof(*paths), GFP_KERNEL);
 504         if (!paths)
 505                 return -ENOMEM;
 506
 507         for (i = 0; i < num_paths; i++) {
 508                 paths[i] = of_icc_get_by_index(dev, i);
 509                 if (IS_ERR(paths[i])) {
 510                         ret = dev_err_probe(dev, PTR_ERR(paths[i]), "%s: Unable to get path%d\n", __func__, i);
 511                         goto err;
 512                 }
 513         }
 514
 515         if (opp_table) {
 516                 opp_table->paths = paths;
 517                 opp_table->path_count = num_paths;
 518                 return 0;
 519         }
 520
 521 err:
 522         while (i--)
 523                 icc_put(paths[i]);
 524
 525         kfree(paths);
 526
 527         return ret;
 528 }
 529 EXPORT_SYMBOL_GPL(dev_pm_opp_of_find_icc_paths);
 530
 531 static bool _opp_is_supported(struct device *dev, struct opp_table *opp_table,
 532                               struct device_node *np)
 533 {
 534         unsigned int levels = opp_table->supported_hw_count;
 535         int count, versions, ret, i, j;
 536         u32 val;
 537
 538         if (!opp_table->supported_hw) {
 539                 /*
 540                  * In the case that no supported_hw has been set by the
 541                  * platform but there is an opp-supported-hw value set for
 542                  * an OPP then the OPP should not be enabled as there is
 543                  * no way to see if the hardware supports it.
 544                  */
 545                 if (of_property_present(np, "opp-supported-hw"))
 546                         return false;
 547                 else
 548                         return true;
 549         }
 550
 551         count = of_property_count_u32_elems(np, "opp-supported-hw");
 552         if (count <= 0 || count % levels) {
 553                 dev_err(dev, "%s: Invalid opp-supported-hw property (%d)\n",
 554                         __func__, count);
 555                 return false;
 556         }
 557
 558         versions = count / levels;
 559
 560         /* All levels in at least one of the versions should match */
 561         for (i = 0; i < versions; i++) {
 562                 bool supported = true;
 563
 564                 for (j = 0; j < levels; j++) {
 565                         ret = of_property_read_u32_index(np, "opp-supported-hw",
 566                                                          i * levels + j, &val);
 567                         if (ret) {
 568                                 dev_warn(dev, "%s: failed to read opp-supported-hw property at index %d: %d\n",
 569                                          __func__, i * levels + j, ret);
 570                                 return false;
 571                         }
 572
 573                         /* Check if the level is supported */
 574                         if (!(val & opp_table->supported_hw[j])) {
 575                                 supported = false;
 576                                 break;
 577                         }
 578                 }
 579
 580                 if (supported)
 581                         return true;
 582         }
 583
 584         return false;
 585 }
 586
 587 static u32 *_parse_named_prop(struct dev_pm_opp *opp, struct device *dev,
 588                               struct opp_table *opp_table,
 589                               const char *prop_type, bool *triplet)
 590 {
 591         struct property *prop = NULL;
 592         char name[NAME_MAX];
 593         int count, ret;
 594         u32 *out;
 595
 596         /* Search for "opp-<prop_type>-<name>" */
 597         if (opp_table->prop_name) {
 598                 snprintf(name, sizeof(name), "opp-%s-%s", prop_type,
 599                          opp_table->prop_name);
 600                 prop = of_find_property(opp->np, name, NULL);
 601         }
 602
 603         if (!prop) {
 604                 /* Search for "opp-<prop_type>" */
 605                 snprintf(name, sizeof(name), "opp-%s", prop_type);
 606                 prop = of_find_property(opp->np, name, NULL);
 607                 if (!prop)
 608                         return NULL;
 609         }
 610
 611         count = of_property_count_u32_elems(opp->np, name);
 612         if (count < 0) {
 613                 dev_err(dev, "%s: Invalid %s property (%d)\n", __func__, name,
 614                         count);
 615                 return ERR_PTR(count);
 616         }
 617
 618         /*
 619          * Initialize regulator_count, if regulator information isn't provided
 620          * by the platform. Now that one of the properties is available, fix the
 621          * regulator_count to 1.
 622          */
 623         if (unlikely(opp_table->regulator_count == -1))
 624                 opp_table->regulator_count = 1;
 625
 626         if (count != opp_table->regulator_count &&
 627             (!triplet || count != opp_table->regulator_count * 3)) {
 628                 dev_err(dev, "%s: Invalid number of elements in %s property (%u) with supplies (%d)\n",
 629                         __func__, prop_type, count, opp_table->regulator_count);
 630                 return ERR_PTR(-EINVAL);
 631         }
 632
 633         out = kmalloc_array(count, sizeof(*out), GFP_KERNEL);
 634         if (!out)
 635                 return ERR_PTR(-EINVAL);
 636
 637         ret = of_property_read_u32_array(opp->np, name, out, count);
 638         if (ret) {
 639                 dev_err(dev, "%s: error parsing %s: %d\n", __func__, name, ret);
 640                 kfree(out);
 641                 return ERR_PTR(-EINVAL);
 642         }
 643
 644         if (triplet)
 645                 *triplet = count != opp_table->regulator_count;
 646
 647         return out;
 648 }
 649
 650 static u32 *opp_parse_microvolt(struct dev_pm_opp *opp, struct device *dev,
 651                                 struct opp_table *opp_table, bool *triplet)
 652 {
 653         u32 *microvolt;
 654
 655         microvolt = _parse_named_prop(opp, dev, opp_table, "microvolt", triplet);
 656         if (IS_ERR(microvolt))
 657                 return microvolt;
 658
 659         if (!microvolt) {
 660                 /*
 661                  * Missing property isn't a problem, but an invalid
 662                  * entry is. This property isn't optional if regulator
 663                  * information is provided. Check only for the first OPP, as
 664                  * regulator_count may get initialized after that to a valid
 665                  * value.
 666                  */
 667                 if (list_empty(&opp_table->opp_list) &&
 668                     opp_table->regulator_count > 0) {
 669                         dev_err(dev, "%s: opp-microvolt missing although OPP managing regulators\n",
 670                                 __func__);
 671                         return ERR_PTR(-EINVAL);
 672                 }
 673         }
 674
 675         return microvolt;
 676 }
 677
 678 static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,
 679                               struct opp_table *opp_table)
 680 {
 681         u32 *microvolt, *microamp, *microwatt;
 682         int ret = 0, i, j;
 683         bool triplet;
 684
 685         microvolt = opp_parse_microvolt(opp, dev, opp_table, &triplet);
 686         if (IS_ERR(microvolt))
 687                 return PTR_ERR(microvolt);
 688
 689         microamp = _parse_named_prop(opp, dev, opp_table, "microamp", NULL);
 690         if (IS_ERR(microamp)) {
 691                 ret = PTR_ERR(microamp);
 692                 goto free_microvolt;
 693         }
 694
 695         microwatt = _parse_named_prop(opp, dev, opp_table, "microwatt", NULL);
 696         if (IS_ERR(microwatt)) {
 697                 ret = PTR_ERR(microwatt);
 698                 goto free_microamp;
 699         }
 700
 701         /*
 702          * Initialize regulator_count if it is uninitialized and no properties
 703          * are found.
 704          */
 705         if (unlikely(opp_table->regulator_count == -1)) {
 706                 opp_table->regulator_count = 0;
 707                 return 0;
 708         }
 709
 710         for (i = 0, j = 0; i < opp_table->regulator_count; i++) {
 711                 if (microvolt) {
 712                         opp->supplies[i].u_volt = microvolt[j++];
 713
 714                         if (triplet) {
 715                                 opp->supplies[i].u_volt_min = microvolt[j++];
 716                                 opp->supplies[i].u_volt_max = microvolt[j++];
 717                         } else {
 718                                 opp->supplies[i].u_volt_min = opp->supplies[i].u_volt;
 719                                 opp->supplies[i].u_volt_max = opp->supplies[i].u_volt;
 720                         }
 721                 }
 722
 723                 if (microamp)
 724                         opp->supplies[i].u_amp = microamp[i];
 725
 726                 if (microwatt)
 727                         opp->supplies[i].u_watt = microwatt[i];
 728         }
 729
 730         kfree(microwatt);
 731 free_microamp:
 732         kfree(microamp);
 733 free_microvolt:
 734         kfree(microvolt);
 735
 736         return ret;
 737 }
 738
 739 /**
 740  * dev_pm_opp_of_remove_table() - Free OPP table entries created from static DT
 741  *                                entries
 742  * @dev:        device pointer used to lookup OPP table.
 743  *
 744  * Free OPPs created using static entries present in DT.
 745  */
 746 void dev_pm_opp_of_remove_table(struct device *dev)
 747 {
 748         dev_pm_opp_remove_table(dev);
 749 }
 750 EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table);
 751
 752 static int _read_rate(struct dev_pm_opp *new_opp, struct opp_table *opp_table,
 753                       struct device_node *np)
 754 {
 755         struct property *prop;
 756         int i, count, ret;
 757         u64 *rates;
 758
 759         prop = of_find_property(np, "opp-hz", NULL);
 760         if (!prop)
 761                 return -ENODEV;
 762
 763         count = prop->length / sizeof(u64);
 764         if (opp_table->clk_count != count) {
 765                 pr_err("%s: Count mismatch between opp-hz and clk_count (%d %d)\n",
 766                        __func__, count, opp_table->clk_count);
 767                 return -EINVAL;
 768         }
 769
 770         rates = kmalloc_array(count, sizeof(*rates), GFP_KERNEL);
 771         if (!rates)
 772                 return -ENOMEM;
 773
 774         ret = of_property_read_u64_array(np, "opp-hz", rates, count);
 775         if (ret) {
 776                 pr_err("%s: Error parsing opp-hz: %d\n", __func__, ret);
 777         } else {
 778                 /*
 779                  * Rate is defined as an unsigned long in clk API, and so
 780                  * casting explicitly to its type. Must be fixed once rate is 64
 781                  * bit guaranteed in clk API.
 782                  */
 783                 for (i = 0; i < count; i++) {
 784                         new_opp->rates[i] = (unsigned long)rates[i];
 785
 786                         /* This will happen for frequencies > 4.29 GHz */
 787                         WARN_ON(new_opp->rates[i] != rates[i]);
 788                 }
 789         }
 790
 791         kfree(rates);
 792
 793         return ret;
 794 }
 795
 796 static int _read_bw(struct dev_pm_opp *new_opp, struct opp_table *opp_table,
 797                     struct device_node *np, bool peak)
 798 {
 799         const char *name = peak ? "opp-peak-kBps" : "opp-avg-kBps";
 800         struct property *prop;
 801         int i, count, ret;
 802         u32 *bw;
 803
 804         prop = of_find_property(np, name, NULL);
 805         if (!prop)
 806                 return -ENODEV;
 807
 808         count = prop->length / sizeof(u32);
 809         if (opp_table->path_count != count) {
 810                 pr_err("%s: Mismatch between %s and paths (%d %d)\n",
 811                                 __func__, name, count, opp_table->path_count);
 812                 return -EINVAL;
 813         }
 814
 815         bw = kmalloc_array(count, sizeof(*bw), GFP_KERNEL);
 816         if (!bw)
 817                 return -ENOMEM;
 818
 819         ret = of_property_read_u32_array(np, name, bw, count);
 820         if (ret) {
 821                 pr_err("%s: Error parsing %s: %d\n", __func__, name, ret);
 822                 goto out;
 823         }
 824
 825         for (i = 0; i < count; i++) {
 826                 if (peak)
 827                         new_opp->bandwidth[i].peak = kBps_to_icc(bw[i]);
 828                 else
 829                         new_opp->bandwidth[i].avg = kBps_to_icc(bw[i]);
 830         }
 831
 832 out:
 833         kfree(bw);
 834         return ret;
 835 }
 836
 837 static int _read_opp_key(struct dev_pm_opp *new_opp,
 838                          struct opp_table *opp_table, struct device_node *np)
 839 {
 840         bool found = false;
 841         int ret;
 842
 843         ret = _read_rate(new_opp, opp_table, np);
 844         if (!ret)
 845                 found = true;
 846         else if (ret != -ENODEV)
 847                 return ret;
 848
 849         /*
 850          * Bandwidth consists of peak and average (optional) values:
 851          * opp-peak-kBps = <path1_value path2_value>;
 852          * opp-avg-kBps = <path1_value path2_value>;
 853          */
 854         ret = _read_bw(new_opp, opp_table, np, true);
 855         if (!ret) {
 856                 found = true;
 857                 ret = _read_bw(new_opp, opp_table, np, false);
 858         }
 859
 860         /* The properties were found but we failed to parse them */
 861         if (ret && ret != -ENODEV)
 862                 return ret;
 863
 864         if (!of_property_read_u32(np, "opp-level", &new_opp->level))
 865                 found = true;
 866
 867         if (found)
 868                 return 0;
 869
 870         return ret;
 871 }
 872
 873 /**
 874  * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings)
 875  * @opp_table:  OPP table
 876  * @dev:        device for which we do this operation
 877  * @np:         device node
 878  *
 879  * This function adds an opp definition to the opp table and returns status. The
 880  * opp can be controlled using dev_pm_opp_enable/disable functions and may be
 881  * removed by dev_pm_opp_remove.
 882  *
 883  * Return:
 884  * Valid OPP pointer:
 885  *              On success
 886  * NULL:
 887  *              Duplicate OPPs (both freq and volt are same) and opp->available
 888  *              OR if the OPP is not supported by hardware.
 889  * ERR_PTR(-EEXIST):
 890  *              Freq are same and volt are different OR
 891  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 892  * ERR_PTR(-ENOMEM):
 893  *              Memory allocation failure
 894  * ERR_PTR(-EINVAL):
 895  *              Failed parsing the OPP node
 896  */
 897 static struct dev_pm_opp *_opp_add_static_v2(struct opp_table *opp_table,
 898                 struct device *dev, struct device_node *np)
 899 {
 900         struct dev_pm_opp *new_opp;
 901         u32 val;
 902         int ret;
 903
 904         new_opp = _opp_allocate(opp_table);
 905         if (!new_opp)
 906                 return ERR_PTR(-ENOMEM);
 907
 908         ret = _read_opp_key(new_opp, opp_table, np);
 909         if (ret < 0) {
 910                 dev_err(dev, "%s: opp key field not found\n", __func__);
 911                 goto free_opp;
 912         }
 913
 914         /* Check if the OPP supports hardware's hierarchy of versions or not */
 915         if (!_opp_is_supported(dev, opp_table, np)) {
 916                 dev_dbg(dev, "OPP not supported by hardware: %s\n",
 917                         of_node_full_name(np));
 918                 goto free_opp;
 919         }
 920
 921         new_opp->turbo = of_property_read_bool(np, "turbo-mode");
 922
 923         new_opp->np = of_node_get(np);
 924         new_opp->dynamic = false;
 925         new_opp->available = true;
 926
 927         ret = _of_opp_alloc_required_opps(opp_table, new_opp);
 928         if (ret)
 929                 goto free_opp;
 930
 931         if (!of_property_read_u32(np, "clock-latency-ns", &val))
 932                 new_opp->clock_latency_ns = val;
 933
 934         ret = opp_parse_supplies(new_opp, dev, opp_table);
 935         if (ret)
 936                 goto free_required_opps;
 937
 938         ret = _opp_add(dev, new_opp, opp_table);
 939         if (ret) {
 940                 /* Don't return error for duplicate OPPs */
 941                 if (ret == -EBUSY)
 942                         ret = 0;
 943                 goto free_required_opps;
 944         }
 945
 946         /* OPP to select on device suspend */
 947         if (of_property_read_bool(np, "opp-suspend")) {
 948                 if (opp_table->suspend_opp) {
 949                         /* Pick the OPP with higher rate/bw/level as suspend OPP */
 950                         if (_opp_compare_key(opp_table, new_opp, opp_table->suspend_opp) == 1) {
 951                                 opp_table->suspend_opp->suspend = false;
 952                                 new_opp->suspend = true;
 953                                 opp_table->suspend_opp = new_opp;
 954                         }
 955                 } else {
 956                         new_opp->suspend = true;
 957                         opp_table->suspend_opp = new_opp;
 958                 }
 959         }
 960
 961         if (new_opp->clock_latency_ns > opp_table->clock_latency_ns_max)
 962                 opp_table->clock_latency_ns_max = new_opp->clock_latency_ns;
 963
 964         pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu level:%u\n",
 965                  __func__, new_opp->turbo, new_opp->rates[0],
 966                  new_opp->supplies[0].u_volt, new_opp->supplies[0].u_volt_min,
 967                  new_opp->supplies[0].u_volt_max, new_opp->clock_latency_ns,
 968                  new_opp->level);
 969
 970         /*
 971          * Notify the changes in the availability of the operable
 972          * frequency/voltage list.
 973          */
 974         blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ADD, new_opp);
 975         return new_opp;
 976
 977 free_required_opps:
 978         _of_opp_free_required_opps(opp_table, new_opp);
 979 free_opp:
 980         _opp_free(new_opp);
 981
 982         return ret ? ERR_PTR(ret) : NULL;
 983 }
 984
 985 /* Initializes OPP tables based on new bindings */
 986 static int _of_add_opp_table_v2(struct device *dev, struct opp_table *opp_table)
 987 {
 988         struct device_node *np;
 989         int ret, count = 0;
 990         struct dev_pm_opp *opp;
 991
 992         /* OPP table is already initialized for the device */
 993         mutex_lock(&opp_table->lock);
 994         if (opp_table->parsed_static_opps) {
 995                 opp_table->parsed_static_opps++;
 996                 mutex_unlock(&opp_table->lock);
 997                 return 0;
 998         }
 999
1000         opp_table->parsed_static_opps = 1;
1001         mutex_unlock(&opp_table->lock);
1002
1003         /* We have opp-table node now, iterate over it and add OPPs */
1004         for_each_available_child_of_node(opp_table->np, np) {
1005                 opp = _opp_add_static_v2(opp_table, dev, np);
1006                 if (IS_ERR(opp)) {
1007                         ret = PTR_ERR(opp);
1008                         dev_err(dev, "%s: Failed to add OPP, %d\n", __func__,
1009                                 ret);
1010                         of_node_put(np);
1011                         goto remove_static_opp;
1012                 } else if (opp) {
1013                         count++;
1014                 }
1015         }
1016
1017         /* There should be one or more OPPs defined */
1018         if (!count) {
1019                 dev_err(dev, "%s: no supported OPPs", __func__);
1020                 ret = -ENOENT;
1021                 goto remove_static_opp;
1022         }
1023
1024         lazy_link_required_opp_table(opp_table);
1025
1026         return 0;
1027
1028 remove_static_opp:
1029         _opp_remove_all_static(opp_table);
1030
1031         return ret;
1032 }
1033
1034 /* Initializes OPP tables based on old-deprecated bindings */
1035 static int _of_add_opp_table_v1(struct device *dev, struct opp_table *opp_table)
1036 {
1037         const struct property *prop;
1038         const __be32 *val;
1039         int nr, ret = 0;
1040
1041         mutex_lock(&opp_table->lock);
1042         if (opp_table->parsed_static_opps) {
1043                 opp_table->parsed_static_opps++;
1044                 mutex_unlock(&opp_table->lock);
1045                 return 0;
1046         }
1047
1048         opp_table->parsed_static_opps = 1;
1049         mutex_unlock(&opp_table->lock);
1050
1051         prop = of_find_property(dev->of_node, "operating-points", NULL);
1052         if (!prop) {
1053                 ret = -ENODEV;
1054                 goto remove_static_opp;
1055         }
1056         if (!prop->value) {
1057                 ret = -ENODATA;
1058                 goto remove_static_opp;
1059         }
1060
1061         /*
1062          * Each OPP is a set of tuples consisting of frequency and
1063          * voltage like <freq-kHz vol-uV>.
1064          */
1065         nr = prop->length / sizeof(u32);
1066         if (nr % 2) {
1067                 dev_err(dev, "%s: Invalid OPP table\n", __func__);
1068                 ret = -EINVAL;
1069                 goto remove_static_opp;
1070         }
1071
1072         val = prop->value;
1073         while (nr) {
1074                 unsigned long freq = be32_to_cpup(val++) * 1000;
1075                 unsigned long volt = be32_to_cpup(val++);
1076                 struct dev_pm_opp_data data = {
1077                         .freq = freq,
1078                         .u_volt = volt,
1079                 };
1080
1081                 ret = _opp_add_v1(opp_table, dev, &data, false);
1082                 if (ret) {
1083                         dev_err(dev, "%s: Failed to add OPP %ld (%d)\n",
1084                                 __func__, data.freq, ret);
1085                         goto remove_static_opp;
1086                 }
1087                 nr -= 2;
1088         }
1089
1090         return 0;
1091
1092 remove_static_opp:
1093         _opp_remove_all_static(opp_table);
1094
1095         return ret;
1096 }
1097
1098 static int _of_add_table_indexed(struct device *dev, int index)
1099 {
1100         struct opp_table *opp_table;
1101         int ret, count;
1102
1103         if (index) {
1104                 /*
1105                  * If only one phandle is present, then the same OPP table
1106                  * applies for all index requests.
1107                  */
1108                 count = of_count_phandle_with_args(dev->of_node,
1109                                                    "operating-points-v2", NULL);
1110                 if (count == 1)
1111                         index = 0;
1112         }
1113
1114         opp_table = _add_opp_table_indexed(dev, index, true);
1115         if (IS_ERR(opp_table))
1116                 return PTR_ERR(opp_table);
1117
1118         /*
1119          * OPPs have two version of bindings now. Also try the old (v1)
1120          * bindings for backward compatibility with older dtbs.
1121          */
1122         if (opp_table->np)
1123                 ret = _of_add_opp_table_v2(dev, opp_table);
1124         else
1125                 ret = _of_add_opp_table_v1(dev, opp_table);
1126
1127         if (ret)
1128                 dev_pm_opp_put_opp_table(opp_table);
1129
1130         return ret;
1131 }
1132
1133 static void devm_pm_opp_of_table_release(void *data)
1134 {
1135         dev_pm_opp_of_remove_table(data);
1136 }
1137
1138 static int _devm_of_add_table_indexed(struct device *dev, int index)
1139 {
1140         int ret;
1141
1142         ret = _of_add_table_indexed(dev, index);
1143         if (ret)
1144                 return ret;
1145
1146         return devm_add_action_or_reset(dev, devm_pm_opp_of_table_release, dev);
1147 }
1148
1149 /**
1150  * devm_pm_opp_of_add_table() - Initialize opp table from device tree
1151  * @dev:        device pointer used to lookup OPP table.
1152  *
1153  * Register the initial OPP table with the OPP library for given device.
1154  *
1155  * The opp_table structure will be freed after the device is destroyed.
1156  *
1157  * Return:
1158  * 0            On success OR
1159  *              Duplicate OPPs (both freq and volt are same) and opp->available
1160  * -EEXIST      Freq are same and volt are different OR
1161  *              Duplicate OPPs (both freq and volt are same) and !opp->available
1162  * -ENOMEM      Memory allocation failure
1163  * -ENODEV      when 'operating-points' property is not found or is invalid data
1164  *              in device node.
1165  * -ENODATA     when empty 'operating-points' property is found
1166  * -EINVAL      when invalid entries are found in opp-v2 table
1167  */
1168 int devm_pm_opp_of_add_table(struct device *dev)
1169 {
1170         return _devm_of_add_table_indexed(dev, 0);
1171 }
1172 EXPORT_SYMBOL_GPL(devm_pm_opp_of_add_table);
1173
1174 /**
1175  * dev_pm_opp_of_add_table() - Initialize opp table from device tree
1176  * @dev:        device pointer used to lookup OPP table.
1177  *
1178  * Register the initial OPP table with the OPP library for given device.
1179  *
1180  * Return:
1181  * 0            On success OR
1182  *              Duplicate OPPs (both freq and volt are same) and opp->available
1183  * -EEXIST      Freq are same and volt are different OR
1184  *              Duplicate OPPs (both freq and volt are same) and !opp->available
1185  * -ENOMEM      Memory allocation failure
1186  * -ENODEV      when 'operating-points' property is not found or is invalid data
1187  *              in device node.
1188  * -ENODATA     when empty 'operating-points' property is found
1189  * -EINVAL      when invalid entries are found in opp-v2 table
1190  */
1191 int dev_pm_opp_of_add_table(struct device *dev)
1192 {
1193         return _of_add_table_indexed(dev, 0);
1194 }
1195 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table);
1196
1197 /**
1198  * dev_pm_opp_of_add_table_indexed() - Initialize indexed opp table from device tree
1199  * @dev:        device pointer used to lookup OPP table.
1200  * @index:      Index number.
1201  *
1202  * Register the initial OPP table with the OPP library for given device only
1203  * using the "operating-points-v2" property.
1204  *
1205  * Return: Refer to dev_pm_opp_of_add_table() for return values.
1206  */
1207 int dev_pm_opp_of_add_table_indexed(struct device *dev, int index)
1208 {
1209         return _of_add_table_indexed(dev, index);
1210 }
1211 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table_indexed);
1212
1213 /**
1214  * devm_pm_opp_of_add_table_indexed() - Initialize indexed opp table from device tree
1215  * @dev:        device pointer used to lookup OPP table.
1216  * @index:      Index number.
1217  *
1218  * This is a resource-managed variant of dev_pm_opp_of_add_table_indexed().
1219  */
1220 int devm_pm_opp_of_add_table_indexed(struct device *dev, int index)
1221 {
1222         return _devm_of_add_table_indexed(dev, index);
1223 }
1224 EXPORT_SYMBOL_GPL(devm_pm_opp_of_add_table_indexed);
1225
1226 /* CPU device specific helpers */
1227
1228 /**
1229  * dev_pm_opp_of_cpumask_remove_table() - Removes OPP table for @cpumask
1230  * @cpumask:    cpumask for which OPP table needs to be removed
1231  *
1232  * This removes the OPP tables for CPUs present in the @cpumask.
1233  * This should be used only to remove static entries created from DT.
1234  */
1235 void dev_pm_opp_of_cpumask_remove_table(const struct cpumask *cpumask)
1236 {
1237         _dev_pm_opp_cpumask_remove_table(cpumask, -1);
1238 }
1239 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_remove_table);
1240
1241 /**
1242  * dev_pm_opp_of_cpumask_add_table() - Adds OPP table for @cpumask
1243  * @cpumask:    cpumask for which OPP table needs to be added.
1244  *
1245  * This adds the OPP tables for CPUs present in the @cpumask.
1246  */
1247 int dev_pm_opp_of_cpumask_add_table(const struct cpumask *cpumask)
1248 {
1249         struct device *cpu_dev;
1250         int cpu, ret;
1251
1252         if (WARN_ON(cpumask_empty(cpumask)))
1253                 return -ENODEV;
1254
1255         for_each_cpu(cpu, cpumask) {
1256                 cpu_dev = get_cpu_device(cpu);
1257                 if (!cpu_dev) {
1258                         pr_err("%s: failed to get cpu%d device\n", __func__,
1259                                cpu);
1260                         ret = -ENODEV;
1261                         goto remove_table;
1262                 }
1263
1264                 ret = dev_pm_opp_of_add_table(cpu_dev);
1265                 if (ret) {
1266                         /*
1267                          * OPP may get registered dynamically, don't print error
1268                          * message here.
1269                          */
1270                         pr_debug("%s: couldn't find opp table for cpu:%d, %d\n",
1271                                  __func__, cpu, ret);
1272
1273                         goto remove_table;
1274                 }
1275         }
1276
1277         return 0;
1278
1279 remove_table:
1280         /* Free all other OPPs */
1281         _dev_pm_opp_cpumask_remove_table(cpumask, cpu);
1282
1283         return ret;
1284 }
1285 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_add_table);
1286
1287 /*
1288  * Works only for OPP v2 bindings.
1289  *
1290  * Returns -ENOENT if operating-points-v2 bindings aren't supported.
1291  */
1292 /**
1293  * dev_pm_opp_of_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with
1294  *                                    @cpu_dev using operating-points-v2
1295  *                                    bindings.
1296  *
1297  * @cpu_dev:    CPU device for which we do this operation
1298  * @cpumask:    cpumask to update with information of sharing CPUs
1299  *
1300  * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev.
1301  *
1302  * Returns -ENOENT if operating-points-v2 isn't present for @cpu_dev.
1303  */
1304 int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev,
1305                                    struct cpumask *cpumask)
1306 {
1307         struct device_node *np, *tmp_np, *cpu_np;
1308         int cpu, ret = 0;
1309
1310         /* Get OPP descriptor node */
1311         np = dev_pm_opp_of_get_opp_desc_node(cpu_dev);
1312         if (!np) {
1313                 dev_dbg(cpu_dev, "%s: Couldn't find opp node.\n", __func__);
1314                 return -ENOENT;
1315         }
1316
1317         cpumask_set_cpu(cpu_dev->id, cpumask);
1318
1319         /* OPPs are shared ? */
1320         if (!of_property_read_bool(np, "opp-shared"))
1321                 goto put_cpu_node;
1322
1323         for_each_possible_cpu(cpu) {
1324                 if (cpu == cpu_dev->id)
1325                         continue;
1326
1327                 cpu_np = of_cpu_device_node_get(cpu);
1328                 if (!cpu_np) {
1329                         dev_err(cpu_dev, "%s: failed to get cpu%d node\n",
1330                                 __func__, cpu);
1331                         ret = -ENOENT;
1332                         goto put_cpu_node;
1333                 }
1334
1335                 /* Get OPP descriptor node */
1336                 tmp_np = _opp_of_get_opp_desc_node(cpu_np, 0);
1337                 of_node_put(cpu_np);
1338                 if (!tmp_np) {
1339                         pr_err("%pOF: Couldn't find opp node\n", cpu_np);
1340                         ret = -ENOENT;
1341                         goto put_cpu_node;
1342                 }
1343
1344                 /* CPUs are sharing opp node */
1345                 if (np == tmp_np)
1346                         cpumask_set_cpu(cpu, cpumask);
1347
1348                 of_node_put(tmp_np);
1349         }
1350
1351 put_cpu_node:
1352         of_node_put(np);
1353         return ret;
1354 }
1355 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus);
1356
1357 /**
1358  * of_get_required_opp_performance_state() - Search for required OPP and return its performance state.
1359  * @np: Node that contains the "required-opps" property.
1360  * @index: Index of the phandle to parse.
1361  *
1362  * Returns the performance state of the OPP pointed out by the "required-opps"
1363  * property at @index in @np.
1364  *
1365  * Return: Zero or positive performance state on success, otherwise negative
1366  * value on errors.
1367  */
1368 int of_get_required_opp_performance_state(struct device_node *np, int index)
1369 {
1370         struct dev_pm_opp *opp;
1371         struct device_node *required_np;
1372         struct opp_table *opp_table;
1373         int pstate = -EINVAL;
1374
1375         required_np = of_parse_required_opp(np, index);
1376         if (!required_np)
1377                 return -ENODEV;
1378
1379         opp_table = _find_table_of_opp_np(required_np);
1380         if (IS_ERR(opp_table)) {
1381                 pr_err("%s: Failed to find required OPP table %pOF: %ld\n",
1382                        __func__, np, PTR_ERR(opp_table));
1383                 goto put_required_np;
1384         }
1385
1386         /* The OPP tables must belong to a genpd */
1387         if (unlikely(!opp_table->is_genpd)) {
1388                 pr_err("%s: Performance state is only valid for genpds.\n", __func__);
1389                 goto put_required_np;
1390         }
1391
1392         opp = _find_opp_of_np(opp_table, required_np);
1393         if (opp) {
1394                 if (opp->level == OPP_LEVEL_UNSET) {
1395                         pr_err("%s: OPP levels aren't available for %pOF\n",
1396                                __func__, np);
1397                 } else {
1398                         pstate = opp->level;
1399                 }
1400                 dev_pm_opp_put(opp);
1401
1402         }
1403
1404         dev_pm_opp_put_opp_table(opp_table);
1405
1406 put_required_np:
1407         of_node_put(required_np);
1408
1409         return pstate;
1410 }
1411 EXPORT_SYMBOL_GPL(of_get_required_opp_performance_state);
1412
1413 /**
1414  * dev_pm_opp_of_has_required_opp - Find out if a required-opps exists.
1415  * @dev: The device to investigate.
1416  *
1417  * Returns true if the device's node has a "operating-points-v2" property and if
1418  * the corresponding node for the opp-table describes opp nodes that uses the
1419  * "required-opps" property.
1420  *
1421  * Return: True if a required-opps is present, else false.
1422  */
1423 bool dev_pm_opp_of_has_required_opp(struct device *dev)
1424 {
1425         struct device_node *opp_np, *np;
1426         int count;
1427
1428         opp_np = _opp_of_get_opp_desc_node(dev->of_node, 0);
1429         if (!opp_np)
1430                 return false;
1431
1432         np = of_get_next_available_child(opp_np, NULL);
1433         of_node_put(opp_np);
1434         if (!np) {
1435                 dev_warn(dev, "Empty OPP table\n");
1436                 return false;
1437         }
1438
1439         count = of_count_phandle_with_args(np, "required-opps", NULL);
1440         of_node_put(np);
1441
1442         return count > 0;
1443 }
1444
1445 /**
1446  * dev_pm_opp_get_of_node() - Gets the DT node corresponding to an opp
1447  * @opp:        opp for which DT node has to be returned for
1448  *
1449  * Return: DT node corresponding to the opp, else 0 on success.
1450  *
1451  * The caller needs to put the node with of_node_put() after using it.
1452  */
1453 struct device_node *dev_pm_opp_get_of_node(struct dev_pm_opp *opp)
1454 {
1455         if (IS_ERR_OR_NULL(opp)) {
1456                 pr_err("%s: Invalid parameters\n", __func__);
1457                 return NULL;
1458         }
1459
1460         return of_node_get(opp->np);
1461 }
1462 EXPORT_SYMBOL_GPL(dev_pm_opp_get_of_node);
1463
1464 /*
1465  * Callback function provided to the Energy Model framework upon registration.
1466  * It provides the power used by @dev at @kHz if it is the frequency of an
1467  * existing OPP, or at the frequency of the first OPP above @kHz otherwise
1468  * (see dev_pm_opp_find_freq_ceil()). This function updates @kHz to the ceiled
1469  * frequency and @uW to the associated power.
1470  *
1471  * Returns 0 on success or a proper -EINVAL value in case of error.
1472  */
1473 static int __maybe_unused
1474 _get_dt_power(struct device *dev, unsigned long *uW, unsigned long *kHz)
1475 {
1476         struct dev_pm_opp *opp;
1477         unsigned long opp_freq, opp_power;
1478
1479         /* Find the right frequency and related OPP */
1480         opp_freq = *kHz * 1000;
1481         opp = dev_pm_opp_find_freq_ceil(dev, &opp_freq);
1482         if (IS_ERR(opp))
1483                 return -EINVAL;
1484
1485         opp_power = dev_pm_opp_get_power(opp);
1486         dev_pm_opp_put(opp);
1487         if (!opp_power)
1488                 return -EINVAL;
1489
1490         *kHz = opp_freq / 1000;
1491         *uW = opp_power;
1492
1493         return 0;
1494 }
1495
1496 /**
1497  * dev_pm_opp_calc_power() - Calculate power value for device with EM
1498  * @dev         : Device for which an Energy Model has to be registered
1499  * @uW          : New power value that is calculated
1500  * @kHz         : Frequency for which the new power is calculated
1501  *
1502  * This computes the power estimated by @dev at @kHz if it is the frequency
1503  * of an existing OPP, or at the frequency of the first OPP above @kHz otherwise
1504  * (see dev_pm_opp_find_freq_ceil()). This function updates @kHz to the ceiled
1505  * frequency and @uW to the associated power. The power is estimated as
1506  * P = C * V^2 * f with C being the device's capacitance and V and f
1507  * respectively the voltage and frequency of the OPP.
1508  * It is also used as a callback function provided to the Energy Model
1509  * framework upon registration.
1510  *
1511  * Returns -EINVAL if the power calculation failed because of missing
1512  * parameters, 0 otherwise.
1513  */
1514 int dev_pm_opp_calc_power(struct device *dev, unsigned long *uW,
1515                           unsigned long *kHz)
1516 {
1517         struct dev_pm_opp *opp;
1518         struct device_node *np;
1519         unsigned long mV, Hz;
1520         u32 cap;
1521         u64 tmp;
1522         int ret;
1523
1524         np = of_node_get(dev->of_node);
1525         if (!np)
1526                 return -EINVAL;
1527
1528         ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1529         of_node_put(np);
1530         if (ret)
1531                 return -EINVAL;
1532
1533         Hz = *kHz * 1000;
1534         opp = dev_pm_opp_find_freq_ceil(dev, &Hz);
1535         if (IS_ERR(opp))
1536                 return -EINVAL;
1537
1538         mV = dev_pm_opp_get_voltage(opp) / 1000;
1539         dev_pm_opp_put(opp);
1540         if (!mV)
1541                 return -EINVAL;
1542
1543         tmp = (u64)cap * mV * mV * (Hz / 1000000);
1544         /* Provide power in micro-Watts */
1545         do_div(tmp, 1000000);
1546
1547         *uW = (unsigned long)tmp;
1548         *kHz = Hz / 1000;
1549
1550         return 0;
1551 }
1552 EXPORT_SYMBOL_GPL(dev_pm_opp_calc_power);
1553
1554 static bool _of_has_opp_microwatt_property(struct device *dev)
1555 {
1556         unsigned long power, freq = 0;
1557         struct dev_pm_opp *opp;
1558
1559         /* Check if at least one OPP has needed property */
1560         opp = dev_pm_opp_find_freq_ceil(dev, &freq);
1561         if (IS_ERR(opp))
1562                 return false;
1563
1564         power = dev_pm_opp_get_power(opp);
1565         dev_pm_opp_put(opp);
1566         if (!power)
1567                 return false;
1568
1569         return true;
1570 }
1571
1572 /**
1573  * dev_pm_opp_of_register_em() - Attempt to register an Energy Model
1574  * @dev         : Device for which an Energy Model has to be registered
1575  * @cpus        : CPUs for which an Energy Model has to be registered. For
1576  *              other type of devices it should be set to NULL.
1577  *
1578  * This checks whether the "dynamic-power-coefficient" devicetree property has
1579  * been specified, and tries to register an Energy Model with it if it has.
1580  * Having this property means the voltages are known for OPPs and the EM
1581  * might be calculated.
1582  */
1583 int dev_pm_opp_of_register_em(struct device *dev, struct cpumask *cpus)
1584 {
1585         struct em_data_callback em_cb;
1586         struct device_node *np;
1587         int ret, nr_opp;
1588         u32 cap;
1589
1590         if (IS_ERR_OR_NULL(dev)) {
1591                 ret = -EINVAL;
1592                 goto failed;
1593         }
1594
1595         nr_opp = dev_pm_opp_get_opp_count(dev);
1596         if (nr_opp <= 0) {
1597                 ret = -EINVAL;
1598                 goto failed;
1599         }
1600
1601         /* First, try to find more precised Energy Model in DT */
1602         if (_of_has_opp_microwatt_property(dev)) {
1603                 EM_SET_ACTIVE_POWER_CB(em_cb, _get_dt_power);
1604                 goto register_em;
1605         }
1606
1607         np = of_node_get(dev->of_node);
1608         if (!np) {
1609                 ret = -EINVAL;
1610                 goto failed;
1611         }
1612
1613         /*
1614          * Register an EM only if the 'dynamic-power-coefficient' property is
1615          * set in devicetree. It is assumed the voltage values are known if that
1616          * property is set since it is useless otherwise. If voltages are not
1617          * known, just let the EM registration fail with an error to alert the
1618          * user about the inconsistent configuration.
1619          */
1620         ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1621         of_node_put(np);
1622         if (ret || !cap) {
1623                 dev_dbg(dev, "Couldn't find proper 'dynamic-power-coefficient' in DT\n");
1624                 ret = -EINVAL;
1625                 goto failed;
1626         }
1627
1628         EM_SET_ACTIVE_POWER_CB(em_cb, dev_pm_opp_calc_power);
1629
1630 register_em:
1631         ret = em_dev_register_perf_domain(dev, nr_opp, &em_cb, cpus, true);
1632         if (ret)
1633                 goto failed;
1634
1635         return 0;
1636
1637 failed:
1638         dev_dbg(dev, "Couldn't register Energy Model %d\n", ret);
1639         return ret;
1640 }
1641 EXPORT_SYMBOL_GPL(dev_pm_opp_of_register_em);