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