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_device.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 /*
  25  * Returns opp descriptor node for a device node, caller must
  26  * do of_node_put().
  27  */
  28 static struct device_node *_opp_of_get_opp_desc_node(struct device_node *np,
  29                                                      int index)
  30 {
  31         /* "operating-points-v2" can be an array for power domain providers */
  32         return of_parse_phandle(np, "operating-points-v2", index);
  33 }
  34
  35 /* Returns opp descriptor node for a device, caller must do of_node_put() */
  36 struct device_node *dev_pm_opp_of_get_opp_desc_node(struct device *dev)
  37 {
  38         return _opp_of_get_opp_desc_node(dev->of_node, 0);
  39 }
  40 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_opp_desc_node);
  41
  42 struct opp_table *_managed_opp(struct device *dev, int index)
  43 {
  44         struct opp_table *opp_table, *managed_table = NULL;
  45         struct device_node *np;
  46
  47         np = _opp_of_get_opp_desc_node(dev->of_node, index);
  48         if (!np)
  49                 return NULL;
  50
  51         list_for_each_entry(opp_table, &opp_tables, node) {
  52                 if (opp_table->np == np) {
  53                         /*
  54                          * Multiple devices can point to the same OPP table and
  55                          * so will have same node-pointer, np.
  56                          *
  57                          * But the OPPs will be considered as shared only if the
  58                          * OPP table contains a "opp-shared" property.
  59                          */
  60                         if (opp_table->shared_opp == OPP_TABLE_ACCESS_SHARED) {
  61                                 _get_opp_table_kref(opp_table);
  62                                 managed_table = opp_table;
  63                         }
  64
  65                         break;
  66                 }
  67         }
  68
  69         of_node_put(np);
  70
  71         return managed_table;
  72 }
  73
  74 /* The caller must call dev_pm_opp_put() after the OPP is used */
  75 static struct dev_pm_opp *_find_opp_of_np(struct opp_table *opp_table,
  76                                           struct device_node *opp_np)
  77 {
  78         struct dev_pm_opp *opp;
  79
  80         mutex_lock(&opp_table->lock);
  81
  82         list_for_each_entry(opp, &opp_table->opp_list, node) {
  83                 if (opp->np == opp_np) {
  84                         dev_pm_opp_get(opp);
  85                         mutex_unlock(&opp_table->lock);
  86                         return opp;
  87                 }
  88         }
  89
  90         mutex_unlock(&opp_table->lock);
  91
  92         return NULL;
  93 }
  94
  95 static struct device_node *of_parse_required_opp(struct device_node *np,
  96                                                  int index)
  97 {
  98         return of_parse_phandle(np, "required-opps", index);
  99 }
 100
 101 /* The caller must call dev_pm_opp_put_opp_table() after the table is used */
 102 static struct opp_table *_find_table_of_opp_np(struct device_node *opp_np)
 103 {
 104         struct opp_table *opp_table;
 105         struct device_node *opp_table_np;
 106
 107         opp_table_np = of_get_parent(opp_np);
 108         if (!opp_table_np)
 109                 goto err;
 110
 111         /* It is safe to put the node now as all we need now is its address */
 112         of_node_put(opp_table_np);
 113
 114         mutex_lock(&opp_table_lock);
 115         list_for_each_entry(opp_table, &opp_tables, node) {
 116                 if (opp_table_np == opp_table->np) {
 117                         _get_opp_table_kref(opp_table);
 118                         mutex_unlock(&opp_table_lock);
 119                         return opp_table;
 120                 }
 121         }
 122         mutex_unlock(&opp_table_lock);
 123
 124 err:
 125         return ERR_PTR(-ENODEV);
 126 }
 127
 128 /* Free resources previously acquired by _opp_table_alloc_required_tables() */
 129 static void _opp_table_free_required_tables(struct opp_table *opp_table)
 130 {
 131         struct opp_table **required_opp_tables = opp_table->required_opp_tables;
 132         int i;
 133
 134         if (!required_opp_tables)
 135                 return;
 136
 137         for (i = 0; i < opp_table->required_opp_count; i++) {
 138                 if (IS_ERR_OR_NULL(required_opp_tables[i]))
 139                         continue;
 140
 141                 dev_pm_opp_put_opp_table(required_opp_tables[i]);
 142         }
 143
 144         kfree(required_opp_tables);
 145
 146         opp_table->required_opp_count = 0;
 147         opp_table->required_opp_tables = NULL;
 148         list_del(&opp_table->lazy);
 149 }
 150
 151 /*
 152  * Populate all devices and opp tables which are part of "required-opps" list.
 153  * Checking only the first OPP node should be enough.
 154  */
 155 static void _opp_table_alloc_required_tables(struct opp_table *opp_table,
 156                                              struct device *dev,
 157                                              struct device_node *opp_np)
 158 {
 159         struct opp_table **required_opp_tables;
 160         struct device_node *required_np, *np;
 161         bool lazy = false;
 162         int count, i;
 163
 164         /* Traversing the first OPP node is all we need */
 165         np = of_get_next_available_child(opp_np, NULL);
 166         if (!np) {
 167                 dev_warn(dev, "Empty OPP table\n");
 168
 169                 return;
 170         }
 171
 172         count = of_count_phandle_with_args(np, "required-opps", NULL);
 173         if (count <= 0)
 174                 goto put_np;
 175
 176         required_opp_tables = kcalloc(count, sizeof(*required_opp_tables),
 177                                       GFP_KERNEL);
 178         if (!required_opp_tables)
 179                 goto put_np;
 180
 181         opp_table->required_opp_tables = required_opp_tables;
 182         opp_table->required_opp_count = count;
 183
 184         for (i = 0; i < count; i++) {
 185                 required_np = of_parse_required_opp(np, i);
 186                 if (!required_np)
 187                         goto free_required_tables;
 188
 189                 required_opp_tables[i] = _find_table_of_opp_np(required_np);
 190                 of_node_put(required_np);
 191
 192                 if (IS_ERR(required_opp_tables[i]))
 193                         lazy = true;
 194         }
 195
 196         /* Let's do the linking later on */
 197         if (lazy)
 198                 list_add(&opp_table->lazy, &lazy_opp_tables);
 199
 200         goto put_np;
 201
 202 free_required_tables:
 203         _opp_table_free_required_tables(opp_table);
 204 put_np:
 205         of_node_put(np);
 206 }
 207
 208 void _of_init_opp_table(struct opp_table *opp_table, struct device *dev,
 209                         int index)
 210 {
 211         struct device_node *np, *opp_np;
 212         u32 val;
 213
 214         /*
 215          * Only required for backward compatibility with v1 bindings, but isn't
 216          * harmful for other cases. And so we do it unconditionally.
 217          */
 218         np = of_node_get(dev->of_node);
 219         if (!np)
 220                 return;
 221
 222         if (!of_property_read_u32(np, "clock-latency", &val))
 223                 opp_table->clock_latency_ns_max = val;
 224         of_property_read_u32(np, "voltage-tolerance",
 225                              &opp_table->voltage_tolerance_v1);
 226
 227         if (of_find_property(np, "#power-domain-cells", NULL))
 228                 opp_table->is_genpd = true;
 229
 230         /* Get OPP table node */
 231         opp_np = _opp_of_get_opp_desc_node(np, index);
 232         of_node_put(np);
 233
 234         if (!opp_np)
 235                 return;
 236
 237         if (of_property_read_bool(opp_np, "opp-shared"))
 238                 opp_table->shared_opp = OPP_TABLE_ACCESS_SHARED;
 239         else
 240                 opp_table->shared_opp = OPP_TABLE_ACCESS_EXCLUSIVE;
 241
 242         opp_table->np = opp_np;
 243
 244         _opp_table_alloc_required_tables(opp_table, dev, opp_np);
 245         of_node_put(opp_np);
 246 }
 247
 248 void _of_clear_opp_table(struct opp_table *opp_table)
 249 {
 250         _opp_table_free_required_tables(opp_table);
 251 }
 252
 253 /*
 254  * Release all resources previously acquired with a call to
 255  * _of_opp_alloc_required_opps().
 256  */
 257 void _of_opp_free_required_opps(struct opp_table *opp_table,
 258                                 struct dev_pm_opp *opp)
 259 {
 260         struct dev_pm_opp **required_opps = opp->required_opps;
 261         int i;
 262
 263         if (!required_opps)
 264                 return;
 265
 266         for (i = 0; i < opp_table->required_opp_count; i++) {
 267                 if (!required_opps[i])
 268                         continue;
 269
 270                 /* Put the reference back */
 271                 dev_pm_opp_put(required_opps[i]);
 272         }
 273
 274         opp->required_opps = NULL;
 275         kfree(required_opps);
 276 }
 277
 278 /* Populate all required OPPs which are part of "required-opps" list */
 279 static int _of_opp_alloc_required_opps(struct opp_table *opp_table,
 280                                        struct dev_pm_opp *opp)
 281 {
 282         struct dev_pm_opp **required_opps;
 283         struct opp_table *required_table;
 284         struct device_node *np;
 285         int i, ret, count = opp_table->required_opp_count;
 286
 287         if (!count)
 288                 return 0;
 289
 290         required_opps = kcalloc(count, sizeof(*required_opps), GFP_KERNEL);
 291         if (!required_opps)
 292                 return -ENOMEM;
 293
 294         opp->required_opps = required_opps;
 295
 296         for (i = 0; i < count; i++) {
 297                 required_table = opp_table->required_opp_tables[i];
 298
 299                 /* Required table not added yet, we will link later */
 300                 if (IS_ERR_OR_NULL(required_table))
 301                         continue;
 302
 303                 np = of_parse_required_opp(opp->np, i);
 304                 if (unlikely(!np)) {
 305                         ret = -ENODEV;
 306                         goto free_required_opps;
 307                 }
 308
 309                 required_opps[i] = _find_opp_of_np(required_table, np);
 310                 of_node_put(np);
 311
 312                 if (!required_opps[i]) {
 313                         pr_err("%s: Unable to find required OPP node: %pOF (%d)\n",
 314                                __func__, opp->np, i);
 315                         ret = -ENODEV;
 316                         goto free_required_opps;
 317                 }
 318         }
 319
 320         return 0;
 321
 322 free_required_opps:
 323         _of_opp_free_required_opps(opp_table, opp);
 324
 325         return ret;
 326 }
 327
 328 /* Link required OPPs for an individual OPP */
 329 static int lazy_link_required_opps(struct opp_table *opp_table,
 330                                    struct opp_table *new_table, int index)
 331 {
 332         struct device_node *required_np;
 333         struct dev_pm_opp *opp;
 334
 335         list_for_each_entry(opp, &opp_table->opp_list, node) {
 336                 required_np = of_parse_required_opp(opp->np, index);
 337                 if (unlikely(!required_np))
 338                         return -ENODEV;
 339
 340                 opp->required_opps[index] = _find_opp_of_np(new_table, required_np);
 341                 of_node_put(required_np);
 342
 343                 if (!opp->required_opps[index]) {
 344                         pr_err("%s: Unable to find required OPP node: %pOF (%d)\n",
 345                                __func__, opp->np, index);
 346                         return -ENODEV;
 347                 }
 348         }
 349
 350         return 0;
 351 }
 352
 353 /* Link required OPPs for all OPPs of the newly added OPP table */
 354 static void lazy_link_required_opp_table(struct opp_table *new_table)
 355 {
 356         struct opp_table *opp_table, *temp, **required_opp_tables;
 357         struct device_node *required_np, *opp_np, *required_table_np;
 358         struct dev_pm_opp *opp;
 359         int i, ret;
 360
 361         mutex_lock(&opp_table_lock);
 362
 363         list_for_each_entry_safe(opp_table, temp, &lazy_opp_tables, lazy) {
 364                 bool lazy = false;
 365
 366                 /* opp_np can't be invalid here */
 367                 opp_np = of_get_next_available_child(opp_table->np, NULL);
 368
 369                 for (i = 0; i < opp_table->required_opp_count; i++) {
 370                         required_opp_tables = opp_table->required_opp_tables;
 371
 372                         /* Required opp-table is already parsed */
 373                         if (!IS_ERR(required_opp_tables[i]))
 374                                 continue;
 375
 376                         /* required_np can't be invalid here */
 377                         required_np = of_parse_required_opp(opp_np, i);
 378                         required_table_np = of_get_parent(required_np);
 379
 380                         of_node_put(required_table_np);
 381                         of_node_put(required_np);
 382
 383                         /*
 384                          * Newly added table isn't the required opp-table for
 385                          * opp_table.
 386                          */
 387                         if (required_table_np != new_table->np) {
 388                                 lazy = true;
 389                                 continue;
 390                         }
 391
 392                         required_opp_tables[i] = new_table;
 393                         _get_opp_table_kref(new_table);
 394
 395                         /* Link OPPs now */
 396                         ret = lazy_link_required_opps(opp_table, new_table, i);
 397                         if (ret) {
 398                                 /* The OPPs will be marked unusable */
 399                                 lazy = false;
 400                                 break;
 401                         }
 402                 }
 403
 404                 of_node_put(opp_np);
 405
 406                 /* All required opp-tables found, remove from lazy list */
 407                 if (!lazy) {
 408                         list_del_init(&opp_table->lazy);
 409
 410                         list_for_each_entry(opp, &opp_table->opp_list, node)
 411                                 _required_opps_available(opp, opp_table->required_opp_count);
 412                 }
 413         }
 414
 415         mutex_unlock(&opp_table_lock);
 416 }
 417
 418 static int _bandwidth_supported(struct device *dev, struct opp_table *opp_table)
 419 {
 420         struct device_node *np, *opp_np;
 421         struct property *prop;
 422
 423         if (!opp_table) {
 424                 np = of_node_get(dev->of_node);
 425                 if (!np)
 426                         return -ENODEV;
 427
 428                 opp_np = _opp_of_get_opp_desc_node(np, 0);
 429                 of_node_put(np);
 430         } else {
 431                 opp_np = of_node_get(opp_table->np);
 432         }
 433
 434         /* Lets not fail in case we are parsing opp-v1 bindings */
 435         if (!opp_np)
 436                 return 0;
 437
 438         /* Checking only first OPP is sufficient */
 439         np = of_get_next_available_child(opp_np, NULL);
 440         of_node_put(opp_np);
 441         if (!np) {
 442                 dev_err(dev, "OPP table empty\n");
 443                 return -EINVAL;
 444         }
 445
 446         prop = of_find_property(np, "opp-peak-kBps", NULL);
 447         of_node_put(np);
 448
 449         if (!prop || !prop->length)
 450                 return 0;
 451
 452         return 1;
 453 }
 454
 455 int dev_pm_opp_of_find_icc_paths(struct device *dev,
 456                                  struct opp_table *opp_table)
 457 {
 458         struct device_node *np;
 459         int ret, i, count, num_paths;
 460         struct icc_path **paths;
 461
 462         ret = _bandwidth_supported(dev, opp_table);
 463         if (ret == -EINVAL)
 464                 return 0; /* Empty OPP table is a valid corner-case, let's not fail */
 465         else if (ret <= 0)
 466                 return ret;
 467
 468         ret = 0;
 469
 470         np = of_node_get(dev->of_node);
 471         if (!np)
 472                 return 0;
 473
 474         count = of_count_phandle_with_args(np, "interconnects",
 475                                            "#interconnect-cells");
 476         of_node_put(np);
 477         if (count < 0)
 478                 return 0;
 479
 480         /* two phandles when #interconnect-cells = <1> */
 481         if (count % 2) {
 482                 dev_err(dev, "%s: Invalid interconnects values\n", __func__);
 483                 return -EINVAL;
 484         }
 485
 486         num_paths = count / 2;
 487         paths = kcalloc(num_paths, sizeof(*paths), GFP_KERNEL);
 488         if (!paths)
 489                 return -ENOMEM;
 490
 491         for (i = 0; i < num_paths; i++) {
 492                 paths[i] = of_icc_get_by_index(dev, i);
 493                 if (IS_ERR(paths[i])) {
 494                         ret = PTR_ERR(paths[i]);
 495                         if (ret != -EPROBE_DEFER) {
 496                                 dev_err(dev, "%s: Unable to get path%d: %d\n",
 497                                         __func__, i, ret);
 498                         }
 499                         goto err;
 500                 }
 501         }
 502
 503         if (opp_table) {
 504                 opp_table->paths = paths;
 505                 opp_table->path_count = num_paths;
 506                 return 0;
 507         }
 508
 509 err:
 510         while (i--)
 511                 icc_put(paths[i]);
 512
 513         kfree(paths);
 514
 515         return ret;
 516 }
 517 EXPORT_SYMBOL_GPL(dev_pm_opp_of_find_icc_paths);
 518
 519 static bool _opp_is_supported(struct device *dev, struct opp_table *opp_table,
 520                               struct device_node *np)
 521 {
 522         unsigned int levels = opp_table->supported_hw_count;
 523         int count, versions, ret, i, j;
 524         u32 val;
 525
 526         if (!opp_table->supported_hw) {
 527                 /*
 528                  * In the case that no supported_hw has been set by the
 529                  * platform but there is an opp-supported-hw value set for
 530                  * an OPP then the OPP should not be enabled as there is
 531                  * no way to see if the hardware supports it.
 532                  */
 533                 if (of_find_property(np, "opp-supported-hw", NULL))
 534                         return false;
 535                 else
 536                         return true;
 537         }
 538
 539         count = of_property_count_u32_elems(np, "opp-supported-hw");
 540         if (count <= 0 || count % levels) {
 541                 dev_err(dev, "%s: Invalid opp-supported-hw property (%d)\n",
 542                         __func__, count);
 543                 return false;
 544         }
 545
 546         versions = count / levels;
 547
 548         /* All levels in at least one of the versions should match */
 549         for (i = 0; i < versions; i++) {
 550                 bool supported = true;
 551
 552                 for (j = 0; j < levels; j++) {
 553                         ret = of_property_read_u32_index(np, "opp-supported-hw",
 554                                                          i * levels + j, &val);
 555                         if (ret) {
 556                                 dev_warn(dev, "%s: failed to read opp-supported-hw property at index %d: %d\n",
 557                                          __func__, i * levels + j, ret);
 558                                 return false;
 559                         }
 560
 561                         /* Check if the level is supported */
 562                         if (!(val & opp_table->supported_hw[j])) {
 563                                 supported = false;
 564                                 break;
 565                         }
 566                 }
 567
 568                 if (supported)
 569                         return true;
 570         }
 571
 572         return false;
 573 }
 574
 575 static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,
 576                               struct opp_table *opp_table)
 577 {
 578         u32 *microvolt, *microamp = NULL, *microwatt = NULL;
 579         int supplies = opp_table->regulator_count;
 580         int vcount, icount, pcount, ret, i, j;
 581         struct property *prop = NULL;
 582         char name[NAME_MAX];
 583
 584         /* Search for "opp-microvolt-<name>" */
 585         if (opp_table->prop_name) {
 586                 snprintf(name, sizeof(name), "opp-microvolt-%s",
 587                          opp_table->prop_name);
 588                 prop = of_find_property(opp->np, name, NULL);
 589         }
 590
 591         if (!prop) {
 592                 /* Search for "opp-microvolt" */
 593                 sprintf(name, "opp-microvolt");
 594                 prop = of_find_property(opp->np, name, NULL);
 595
 596                 /* Missing property isn't a problem, but an invalid entry is */
 597                 if (!prop) {
 598                         if (unlikely(supplies == -1)) {
 599                                 /* Initialize regulator_count */
 600                                 opp_table->regulator_count = 0;
 601                                 return 0;
 602                         }
 603
 604                         if (!supplies)
 605                                 return 0;
 606
 607                         dev_err(dev, "%s: opp-microvolt missing although OPP managing regulators\n",
 608                                 __func__);
 609                         return -EINVAL;
 610                 }
 611         }
 612
 613         if (unlikely(supplies == -1)) {
 614                 /* Initialize regulator_count */
 615                 supplies = opp_table->regulator_count = 1;
 616         } else if (unlikely(!supplies)) {
 617                 dev_err(dev, "%s: opp-microvolt wasn't expected\n", __func__);
 618                 return -EINVAL;
 619         }
 620
 621         vcount = of_property_count_u32_elems(opp->np, name);
 622         if (vcount < 0) {
 623                 dev_err(dev, "%s: Invalid %s property (%d)\n",
 624                         __func__, name, vcount);
 625                 return vcount;
 626         }
 627
 628         /* There can be one or three elements per supply */
 629         if (vcount != supplies && vcount != supplies * 3) {
 630                 dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
 631                         __func__, name, vcount, supplies);
 632                 return -EINVAL;
 633         }
 634
 635         microvolt = kmalloc_array(vcount, sizeof(*microvolt), GFP_KERNEL);
 636         if (!microvolt)
 637                 return -ENOMEM;
 638
 639         ret = of_property_read_u32_array(opp->np, name, microvolt, vcount);
 640         if (ret) {
 641                 dev_err(dev, "%s: error parsing %s: %d\n", __func__, name, ret);
 642                 ret = -EINVAL;
 643                 goto free_microvolt;
 644         }
 645
 646         /* Search for "opp-microamp-<name>" */
 647         prop = NULL;
 648         if (opp_table->prop_name) {
 649                 snprintf(name, sizeof(name), "opp-microamp-%s",
 650                          opp_table->prop_name);
 651                 prop = of_find_property(opp->np, name, NULL);
 652         }
 653
 654         if (!prop) {
 655                 /* Search for "opp-microamp" */
 656                 sprintf(name, "opp-microamp");
 657                 prop = of_find_property(opp->np, name, NULL);
 658         }
 659
 660         if (prop) {
 661                 icount = of_property_count_u32_elems(opp->np, name);
 662                 if (icount < 0) {
 663                         dev_err(dev, "%s: Invalid %s property (%d)\n", __func__,
 664                                 name, icount);
 665                         ret = icount;
 666                         goto free_microvolt;
 667                 }
 668
 669                 if (icount != supplies) {
 670                         dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
 671                                 __func__, name, icount, supplies);
 672                         ret = -EINVAL;
 673                         goto free_microvolt;
 674                 }
 675
 676                 microamp = kmalloc_array(icount, sizeof(*microamp), GFP_KERNEL);
 677                 if (!microamp) {
 678                         ret = -EINVAL;
 679                         goto free_microvolt;
 680                 }
 681
 682                 ret = of_property_read_u32_array(opp->np, name, microamp,
 683                                                  icount);
 684                 if (ret) {
 685                         dev_err(dev, "%s: error parsing %s: %d\n", __func__,
 686                                 name, ret);
 687                         ret = -EINVAL;
 688                         goto free_microamp;
 689                 }
 690         }
 691
 692         /* Search for "opp-microwatt" */
 693         sprintf(name, "opp-microwatt");
 694         prop = of_find_property(opp->np, name, NULL);
 695
 696         if (prop) {
 697                 pcount = of_property_count_u32_elems(opp->np, name);
 698                 if (pcount < 0) {
 699                         dev_err(dev, "%s: Invalid %s property (%d)\n", __func__,
 700                                 name, pcount);
 701                         ret = pcount;
 702                         goto free_microamp;
 703                 }
 704
 705                 if (pcount != supplies) {
 706                         dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
 707                                 __func__, name, pcount, supplies);
 708                         ret = -EINVAL;
 709                         goto free_microamp;
 710                 }
 711
 712                 microwatt = kmalloc_array(pcount, sizeof(*microwatt),
 713                                           GFP_KERNEL);
 714                 if (!microwatt) {
 715                         ret = -EINVAL;
 716                         goto free_microamp;
 717                 }
 718
 719                 ret = of_property_read_u32_array(opp->np, name, microwatt,
 720                                                  pcount);
 721                 if (ret) {
 722                         dev_err(dev, "%s: error parsing %s: %d\n", __func__,
 723                                 name, ret);
 724                         ret = -EINVAL;
 725                         goto free_microwatt;
 726                 }
 727         }
 728
 729         for (i = 0, j = 0; i < supplies; i++) {
 730                 opp->supplies[i].u_volt = microvolt[j++];
 731
 732                 if (vcount == supplies) {
 733                         opp->supplies[i].u_volt_min = opp->supplies[i].u_volt;
 734                         opp->supplies[i].u_volt_max = opp->supplies[i].u_volt;
 735                 } else {
 736                         opp->supplies[i].u_volt_min = microvolt[j++];
 737                         opp->supplies[i].u_volt_max = microvolt[j++];
 738                 }
 739
 740                 if (microamp)
 741                         opp->supplies[i].u_amp = microamp[i];
 742
 743                 if (microwatt)
 744                         opp->supplies[i].u_watt = microwatt[i];
 745         }
 746
 747 free_microwatt:
 748         kfree(microwatt);
 749 free_microamp:
 750         kfree(microamp);
 751 free_microvolt:
 752         kfree(microvolt);
 753
 754         return ret;
 755 }
 756
 757 /**
 758  * dev_pm_opp_of_remove_table() - Free OPP table entries created from static DT
 759  *                                entries
 760  * @dev:        device pointer used to lookup OPP table.
 761  *
 762  * Free OPPs created using static entries present in DT.
 763  */
 764 void dev_pm_opp_of_remove_table(struct device *dev)
 765 {
 766         dev_pm_opp_remove_table(dev);
 767 }
 768 EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table);
 769
 770 static int _read_bw(struct dev_pm_opp *new_opp, struct opp_table *table,
 771                     struct device_node *np, bool peak)
 772 {
 773         const char *name = peak ? "opp-peak-kBps" : "opp-avg-kBps";
 774         struct property *prop;
 775         int i, count, ret;
 776         u32 *bw;
 777
 778         prop = of_find_property(np, name, NULL);
 779         if (!prop)
 780                 return -ENODEV;
 781
 782         count = prop->length / sizeof(u32);
 783         if (table->path_count != count) {
 784                 pr_err("%s: Mismatch between %s and paths (%d %d)\n",
 785                                 __func__, name, count, table->path_count);
 786                 return -EINVAL;
 787         }
 788
 789         bw = kmalloc_array(count, sizeof(*bw), GFP_KERNEL);
 790         if (!bw)
 791                 return -ENOMEM;
 792
 793         ret = of_property_read_u32_array(np, name, bw, count);
 794         if (ret) {
 795                 pr_err("%s: Error parsing %s: %d\n", __func__, name, ret);
 796                 goto out;
 797         }
 798
 799         for (i = 0; i < count; i++) {
 800                 if (peak)
 801                         new_opp->bandwidth[i].peak = kBps_to_icc(bw[i]);
 802                 else
 803                         new_opp->bandwidth[i].avg = kBps_to_icc(bw[i]);
 804         }
 805
 806 out:
 807         kfree(bw);
 808         return ret;
 809 }
 810
 811 static int _read_opp_key(struct dev_pm_opp *new_opp, struct opp_table *table,
 812                          struct device_node *np, bool *rate_not_available)
 813 {
 814         bool found = false;
 815         u64 rate;
 816         int ret;
 817
 818         ret = of_property_read_u64(np, "opp-hz", &rate);
 819         if (!ret) {
 820                 /*
 821                  * Rate is defined as an unsigned long in clk API, and so
 822                  * casting explicitly to its type. Must be fixed once rate is 64
 823                  * bit guaranteed in clk API.
 824                  */
 825                 new_opp->rate = (unsigned long)rate;
 826                 found = true;
 827         }
 828         *rate_not_available = !!ret;
 829
 830         /*
 831          * Bandwidth consists of peak and average (optional) values:
 832          * opp-peak-kBps = <path1_value path2_value>;
 833          * opp-avg-kBps = <path1_value path2_value>;
 834          */
 835         ret = _read_bw(new_opp, table, np, true);
 836         if (!ret) {
 837                 found = true;
 838                 ret = _read_bw(new_opp, table, np, false);
 839         }
 840
 841         /* The properties were found but we failed to parse them */
 842         if (ret && ret != -ENODEV)
 843                 return ret;
 844
 845         if (!of_property_read_u32(np, "opp-level", &new_opp->level))
 846                 found = true;
 847
 848         if (found)
 849                 return 0;
 850
 851         return ret;
 852 }
 853
 854 /**
 855  * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings)
 856  * @opp_table:  OPP table
 857  * @dev:        device for which we do this operation
 858  * @np:         device node
 859  *
 860  * This function adds an opp definition to the opp table and returns status. The
 861  * opp can be controlled using dev_pm_opp_enable/disable functions and may be
 862  * removed by dev_pm_opp_remove.
 863  *
 864  * Return:
 865  * Valid OPP pointer:
 866  *              On success
 867  * NULL:
 868  *              Duplicate OPPs (both freq and volt are same) and opp->available
 869  *              OR if the OPP is not supported by hardware.
 870  * ERR_PTR(-EEXIST):
 871  *              Freq are same and volt are different OR
 872  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 873  * ERR_PTR(-ENOMEM):
 874  *              Memory allocation failure
 875  * ERR_PTR(-EINVAL):
 876  *              Failed parsing the OPP node
 877  */
 878 static struct dev_pm_opp *_opp_add_static_v2(struct opp_table *opp_table,
 879                 struct device *dev, struct device_node *np)
 880 {
 881         struct dev_pm_opp *new_opp;
 882         u32 val;
 883         int ret;
 884         bool rate_not_available = false;
 885
 886         new_opp = _opp_allocate(opp_table);
 887         if (!new_opp)
 888                 return ERR_PTR(-ENOMEM);
 889
 890         ret = _read_opp_key(new_opp, opp_table, np, &rate_not_available);
 891         if (ret < 0) {
 892                 dev_err(dev, "%s: opp key field not found\n", __func__);
 893                 goto free_opp;
 894         }
 895
 896         /* Check if the OPP supports hardware's hierarchy of versions or not */
 897         if (!_opp_is_supported(dev, opp_table, np)) {
 898                 dev_dbg(dev, "OPP not supported by hardware: %lu\n",
 899                         new_opp->rate);
 900                 goto free_opp;
 901         }
 902
 903         new_opp->turbo = of_property_read_bool(np, "turbo-mode");
 904
 905         new_opp->np = np;
 906         new_opp->dynamic = false;
 907         new_opp->available = true;
 908
 909         ret = _of_opp_alloc_required_opps(opp_table, new_opp);
 910         if (ret)
 911                 goto free_opp;
 912
 913         if (!of_property_read_u32(np, "clock-latency-ns", &val))
 914                 new_opp->clock_latency_ns = val;
 915
 916         ret = opp_parse_supplies(new_opp, dev, opp_table);
 917         if (ret)
 918                 goto free_required_opps;
 919
 920         if (opp_table->is_genpd)
 921                 new_opp->pstate = pm_genpd_opp_to_performance_state(dev, new_opp);
 922
 923         ret = _opp_add(dev, new_opp, opp_table, rate_not_available);
 924         if (ret) {
 925                 /* Don't return error for duplicate OPPs */
 926                 if (ret == -EBUSY)
 927                         ret = 0;
 928                 goto free_required_opps;
 929         }
 930
 931         /* OPP to select on device suspend */
 932         if (of_property_read_bool(np, "opp-suspend")) {
 933                 if (opp_table->suspend_opp) {
 934                         /* Pick the OPP with higher rate as suspend OPP */
 935                         if (new_opp->rate > opp_table->suspend_opp->rate) {
 936                                 opp_table->suspend_opp->suspend = false;
 937                                 new_opp->suspend = true;
 938                                 opp_table->suspend_opp = new_opp;
 939                         }
 940                 } else {
 941                         new_opp->suspend = true;
 942                         opp_table->suspend_opp = new_opp;
 943                 }
 944         }
 945
 946         if (new_opp->clock_latency_ns > opp_table->clock_latency_ns_max)
 947                 opp_table->clock_latency_ns_max = new_opp->clock_latency_ns;
 948
 949         pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu level:%u\n",
 950                  __func__, new_opp->turbo, new_opp->rate,
 951                  new_opp->supplies[0].u_volt, new_opp->supplies[0].u_volt_min,
 952                  new_opp->supplies[0].u_volt_max, new_opp->clock_latency_ns,
 953                  new_opp->level);
 954
 955         /*
 956          * Notify the changes in the availability of the operable
 957          * frequency/voltage list.
 958          */
 959         blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ADD, new_opp);
 960         return new_opp;
 961
 962 free_required_opps:
 963         _of_opp_free_required_opps(opp_table, new_opp);
 964 free_opp:
 965         _opp_free(new_opp);
 966
 967         return ret ? ERR_PTR(ret) : NULL;
 968 }
 969
 970 /* Initializes OPP tables based on new bindings */
 971 static int _of_add_opp_table_v2(struct device *dev, struct opp_table *opp_table)
 972 {
 973         struct device_node *np;
 974         int ret, count = 0;
 975         struct dev_pm_opp *opp;
 976
 977         /* OPP table is already initialized for the device */
 978         mutex_lock(&opp_table->lock);
 979         if (opp_table->parsed_static_opps) {
 980                 opp_table->parsed_static_opps++;
 981                 mutex_unlock(&opp_table->lock);
 982                 return 0;
 983         }
 984
 985         opp_table->parsed_static_opps = 1;
 986         mutex_unlock(&opp_table->lock);
 987
 988         /* We have opp-table node now, iterate over it and add OPPs */
 989         for_each_available_child_of_node(opp_table->np, np) {
 990                 opp = _opp_add_static_v2(opp_table, dev, np);
 991                 if (IS_ERR(opp)) {
 992                         ret = PTR_ERR(opp);
 993                         dev_err(dev, "%s: Failed to add OPP, %d\n", __func__,
 994                                 ret);
 995                         of_node_put(np);
 996                         goto remove_static_opp;
 997                 } else if (opp) {
 998                         count++;
 999                 }
1000         }
1001
1002         /* There should be one or more OPPs defined */
1003         if (!count) {
1004                 dev_err(dev, "%s: no supported OPPs", __func__);
1005                 ret = -ENOENT;
1006                 goto remove_static_opp;
1007         }
1008
1009         list_for_each_entry(opp, &opp_table->opp_list, node) {
1010                 /* Any non-zero performance state would enable the feature */
1011                 if (opp->pstate) {
1012                         opp_table->genpd_performance_state = true;
1013                         break;
1014                 }
1015         }
1016
1017         lazy_link_required_opp_table(opp_table);
1018
1019         return 0;
1020
1021 remove_static_opp:
1022         _opp_remove_all_static(opp_table);
1023
1024         return ret;
1025 }
1026
1027 /* Initializes OPP tables based on old-deprecated bindings */
1028 static int _of_add_opp_table_v1(struct device *dev, struct opp_table *opp_table)
1029 {
1030         const struct property *prop;
1031         const __be32 *val;
1032         int nr, ret = 0;
1033
1034         mutex_lock(&opp_table->lock);
1035         if (opp_table->parsed_static_opps) {
1036                 opp_table->parsed_static_opps++;
1037                 mutex_unlock(&opp_table->lock);
1038                 return 0;
1039         }
1040
1041         opp_table->parsed_static_opps = 1;
1042         mutex_unlock(&opp_table->lock);
1043
1044         prop = of_find_property(dev->of_node, "operating-points", NULL);
1045         if (!prop) {
1046                 ret = -ENODEV;
1047                 goto remove_static_opp;
1048         }
1049         if (!prop->value) {
1050                 ret = -ENODATA;
1051                 goto remove_static_opp;
1052         }
1053
1054         /*
1055          * Each OPP is a set of tuples consisting of frequency and
1056          * voltage like <freq-kHz vol-uV>.
1057          */
1058         nr = prop->length / sizeof(u32);
1059         if (nr % 2) {
1060                 dev_err(dev, "%s: Invalid OPP table\n", __func__);
1061                 ret = -EINVAL;
1062                 goto remove_static_opp;
1063         }
1064
1065         val = prop->value;
1066         while (nr) {
1067                 unsigned long freq = be32_to_cpup(val++) * 1000;
1068                 unsigned long volt = be32_to_cpup(val++);
1069
1070                 ret = _opp_add_v1(opp_table, dev, freq, volt, false);
1071                 if (ret) {
1072                         dev_err(dev, "%s: Failed to add OPP %ld (%d)\n",
1073                                 __func__, freq, ret);
1074                         goto remove_static_opp;
1075                 }
1076                 nr -= 2;
1077         }
1078
1079         return 0;
1080
1081 remove_static_opp:
1082         _opp_remove_all_static(opp_table);
1083
1084         return ret;
1085 }
1086
1087 static int _of_add_table_indexed(struct device *dev, int index, bool getclk)
1088 {
1089         struct opp_table *opp_table;
1090         int ret, count;
1091
1092         if (index) {
1093                 /*
1094                  * If only one phandle is present, then the same OPP table
1095                  * applies for all index requests.
1096                  */
1097                 count = of_count_phandle_with_args(dev->of_node,
1098                                                    "operating-points-v2", NULL);
1099                 if (count == 1)
1100                         index = 0;
1101         }
1102
1103         opp_table = _add_opp_table_indexed(dev, index, getclk);
1104         if (IS_ERR(opp_table))
1105                 return PTR_ERR(opp_table);
1106
1107         /*
1108          * OPPs have two version of bindings now. Also try the old (v1)
1109          * bindings for backward compatibility with older dtbs.
1110          */
1111         if (opp_table->np)
1112                 ret = _of_add_opp_table_v2(dev, opp_table);
1113         else
1114                 ret = _of_add_opp_table_v1(dev, opp_table);
1115
1116         if (ret)
1117                 dev_pm_opp_put_opp_table(opp_table);
1118
1119         return ret;
1120 }
1121
1122 static void devm_pm_opp_of_table_release(void *data)
1123 {
1124         dev_pm_opp_of_remove_table(data);
1125 }
1126
1127 static int _devm_of_add_table_indexed(struct device *dev, int index, bool getclk)
1128 {
1129         int ret;
1130
1131         ret = _of_add_table_indexed(dev, index, getclk);
1132         if (ret)
1133                 return ret;
1134
1135         return devm_add_action_or_reset(dev, devm_pm_opp_of_table_release, dev);
1136 }
1137
1138 /**
1139  * devm_pm_opp_of_add_table() - Initialize opp table from device tree
1140  * @dev:        device pointer used to lookup OPP table.
1141  *
1142  * Register the initial OPP table with the OPP library for given device.
1143  *
1144  * The opp_table structure will be freed after the device is destroyed.
1145  *
1146  * Return:
1147  * 0            On success OR
1148  *              Duplicate OPPs (both freq and volt are same) and opp->available
1149  * -EEXIST      Freq are same and volt are different OR
1150  *              Duplicate OPPs (both freq and volt are same) and !opp->available
1151  * -ENOMEM      Memory allocation failure
1152  * -ENODEV      when 'operating-points' property is not found or is invalid data
1153  *              in device node.
1154  * -ENODATA     when empty 'operating-points' property is found
1155  * -EINVAL      when invalid entries are found in opp-v2 table
1156  */
1157 int devm_pm_opp_of_add_table(struct device *dev)
1158 {
1159         return _devm_of_add_table_indexed(dev, 0, true);
1160 }
1161 EXPORT_SYMBOL_GPL(devm_pm_opp_of_add_table);
1162
1163 /**
1164  * dev_pm_opp_of_add_table() - Initialize opp table from device tree
1165  * @dev:        device pointer used to lookup OPP table.
1166  *
1167  * Register the initial OPP table with the OPP library for given device.
1168  *
1169  * Return:
1170  * 0            On success OR
1171  *              Duplicate OPPs (both freq and volt are same) and opp->available
1172  * -EEXIST      Freq are same and volt are different OR
1173  *              Duplicate OPPs (both freq and volt are same) and !opp->available
1174  * -ENOMEM      Memory allocation failure
1175  * -ENODEV      when 'operating-points' property is not found or is invalid data
1176  *              in device node.
1177  * -ENODATA     when empty 'operating-points' property is found
1178  * -EINVAL      when invalid entries are found in opp-v2 table
1179  */
1180 int dev_pm_opp_of_add_table(struct device *dev)
1181 {
1182         return _of_add_table_indexed(dev, 0, true);
1183 }
1184 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table);
1185
1186 /**
1187  * dev_pm_opp_of_add_table_indexed() - Initialize indexed opp table from device tree
1188  * @dev:        device pointer used to lookup OPP table.
1189  * @index:      Index number.
1190  *
1191  * Register the initial OPP table with the OPP library for given device only
1192  * using the "operating-points-v2" property.
1193  *
1194  * Return: Refer to dev_pm_opp_of_add_table() for return values.
1195  */
1196 int dev_pm_opp_of_add_table_indexed(struct device *dev, int index)
1197 {
1198         return _of_add_table_indexed(dev, index, true);
1199 }
1200 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table_indexed);
1201
1202 /**
1203  * devm_pm_opp_of_add_table_indexed() - Initialize indexed opp table from device tree
1204  * @dev:        device pointer used to lookup OPP table.
1205  * @index:      Index number.
1206  *
1207  * This is a resource-managed variant of dev_pm_opp_of_add_table_indexed().
1208  */
1209 int devm_pm_opp_of_add_table_indexed(struct device *dev, int index)
1210 {
1211         return _devm_of_add_table_indexed(dev, index, true);
1212 }
1213 EXPORT_SYMBOL_GPL(devm_pm_opp_of_add_table_indexed);
1214
1215 /**
1216  * dev_pm_opp_of_add_table_noclk() - Initialize indexed opp table from device
1217  *              tree without getting clk for device.
1218  * @dev:        device pointer used to lookup OPP table.
1219  * @index:      Index number.
1220  *
1221  * Register the initial OPP table with the OPP library for given device only
1222  * using the "operating-points-v2" property. Do not try to get the clk for the
1223  * device.
1224  *
1225  * Return: Refer to dev_pm_opp_of_add_table() for return values.
1226  */
1227 int dev_pm_opp_of_add_table_noclk(struct device *dev, int index)
1228 {
1229         return _of_add_table_indexed(dev, index, false);
1230 }
1231 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table_noclk);
1232
1233 /**
1234  * devm_pm_opp_of_add_table_noclk() - Initialize indexed opp table from device
1235  *              tree without getting clk for device.
1236  * @dev:        device pointer used to lookup OPP table.
1237  * @index:      Index number.
1238  *
1239  * This is a resource-managed variant of dev_pm_opp_of_add_table_noclk().
1240  */
1241 int devm_pm_opp_of_add_table_noclk(struct device *dev, int index)
1242 {
1243         return _devm_of_add_table_indexed(dev, index, false);
1244 }
1245 EXPORT_SYMBOL_GPL(devm_pm_opp_of_add_table_noclk);
1246
1247 /* CPU device specific helpers */
1248
1249 /**
1250  * dev_pm_opp_of_cpumask_remove_table() - Removes OPP table for @cpumask
1251  * @cpumask:    cpumask for which OPP table needs to be removed
1252  *
1253  * This removes the OPP tables for CPUs present in the @cpumask.
1254  * This should be used only to remove static entries created from DT.
1255  */
1256 void dev_pm_opp_of_cpumask_remove_table(const struct cpumask *cpumask)
1257 {
1258         _dev_pm_opp_cpumask_remove_table(cpumask, -1);
1259 }
1260 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_remove_table);
1261
1262 /**
1263  * dev_pm_opp_of_cpumask_add_table() - Adds OPP table for @cpumask
1264  * @cpumask:    cpumask for which OPP table needs to be added.
1265  *
1266  * This adds the OPP tables for CPUs present in the @cpumask.
1267  */
1268 int dev_pm_opp_of_cpumask_add_table(const struct cpumask *cpumask)
1269 {
1270         struct device *cpu_dev;
1271         int cpu, ret;
1272
1273         if (WARN_ON(cpumask_empty(cpumask)))
1274                 return -ENODEV;
1275
1276         for_each_cpu(cpu, cpumask) {
1277                 cpu_dev = get_cpu_device(cpu);
1278                 if (!cpu_dev) {
1279                         pr_err("%s: failed to get cpu%d device\n", __func__,
1280                                cpu);
1281                         ret = -ENODEV;
1282                         goto remove_table;
1283                 }
1284
1285                 ret = dev_pm_opp_of_add_table(cpu_dev);
1286                 if (ret) {
1287                         /*
1288                          * OPP may get registered dynamically, don't print error
1289                          * message here.
1290                          */
1291                         pr_debug("%s: couldn't find opp table for cpu:%d, %d\n",
1292                                  __func__, cpu, ret);
1293
1294                         goto remove_table;
1295                 }
1296         }
1297
1298         return 0;
1299
1300 remove_table:
1301         /* Free all other OPPs */
1302         _dev_pm_opp_cpumask_remove_table(cpumask, cpu);
1303
1304         return ret;
1305 }
1306 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_add_table);
1307
1308 /*
1309  * Works only for OPP v2 bindings.
1310  *
1311  * Returns -ENOENT if operating-points-v2 bindings aren't supported.
1312  */
1313 /**
1314  * dev_pm_opp_of_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with
1315  *                                    @cpu_dev using operating-points-v2
1316  *                                    bindings.
1317  *
1318  * @cpu_dev:    CPU device for which we do this operation
1319  * @cpumask:    cpumask to update with information of sharing CPUs
1320  *
1321  * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev.
1322  *
1323  * Returns -ENOENT if operating-points-v2 isn't present for @cpu_dev.
1324  */
1325 int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev,
1326                                    struct cpumask *cpumask)
1327 {
1328         struct device_node *np, *tmp_np, *cpu_np;
1329         int cpu, ret = 0;
1330
1331         /* Get OPP descriptor node */
1332         np = dev_pm_opp_of_get_opp_desc_node(cpu_dev);
1333         if (!np) {
1334                 dev_dbg(cpu_dev, "%s: Couldn't find opp node.\n", __func__);
1335                 return -ENOENT;
1336         }
1337
1338         cpumask_set_cpu(cpu_dev->id, cpumask);
1339
1340         /* OPPs are shared ? */
1341         if (!of_property_read_bool(np, "opp-shared"))
1342                 goto put_cpu_node;
1343
1344         for_each_possible_cpu(cpu) {
1345                 if (cpu == cpu_dev->id)
1346                         continue;
1347
1348                 cpu_np = of_cpu_device_node_get(cpu);
1349                 if (!cpu_np) {
1350                         dev_err(cpu_dev, "%s: failed to get cpu%d node\n",
1351                                 __func__, cpu);
1352                         ret = -ENOENT;
1353                         goto put_cpu_node;
1354                 }
1355
1356                 /* Get OPP descriptor node */
1357                 tmp_np = _opp_of_get_opp_desc_node(cpu_np, 0);
1358                 of_node_put(cpu_np);
1359                 if (!tmp_np) {
1360                         pr_err("%pOF: Couldn't find opp node\n", cpu_np);
1361                         ret = -ENOENT;
1362                         goto put_cpu_node;
1363                 }
1364
1365                 /* CPUs are sharing opp node */
1366                 if (np == tmp_np)
1367                         cpumask_set_cpu(cpu, cpumask);
1368
1369                 of_node_put(tmp_np);
1370         }
1371
1372 put_cpu_node:
1373         of_node_put(np);
1374         return ret;
1375 }
1376 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus);
1377
1378 /**
1379  * of_get_required_opp_performance_state() - Search for required OPP and return its performance state.
1380  * @np: Node that contains the "required-opps" property.
1381  * @index: Index of the phandle to parse.
1382  *
1383  * Returns the performance state of the OPP pointed out by the "required-opps"
1384  * property at @index in @np.
1385  *
1386  * Return: Zero or positive performance state on success, otherwise negative
1387  * value on errors.
1388  */
1389 int of_get_required_opp_performance_state(struct device_node *np, int index)
1390 {
1391         struct dev_pm_opp *opp;
1392         struct device_node *required_np;
1393         struct opp_table *opp_table;
1394         int pstate = -EINVAL;
1395
1396         required_np = of_parse_required_opp(np, index);
1397         if (!required_np)
1398                 return -ENODEV;
1399
1400         opp_table = _find_table_of_opp_np(required_np);
1401         if (IS_ERR(opp_table)) {
1402                 pr_err("%s: Failed to find required OPP table %pOF: %ld\n",
1403                        __func__, np, PTR_ERR(opp_table));
1404                 goto put_required_np;
1405         }
1406
1407         opp = _find_opp_of_np(opp_table, required_np);
1408         if (opp) {
1409                 pstate = opp->pstate;
1410                 dev_pm_opp_put(opp);
1411         }
1412
1413         dev_pm_opp_put_opp_table(opp_table);
1414
1415 put_required_np:
1416         of_node_put(required_np);
1417
1418         return pstate;
1419 }
1420 EXPORT_SYMBOL_GPL(of_get_required_opp_performance_state);
1421
1422 /**
1423  * dev_pm_opp_get_of_node() - Gets the DT node corresponding to an opp
1424  * @opp:        opp for which DT node has to be returned for
1425  *
1426  * Return: DT node corresponding to the opp, else 0 on success.
1427  *
1428  * The caller needs to put the node with of_node_put() after using it.
1429  */
1430 struct device_node *dev_pm_opp_get_of_node(struct dev_pm_opp *opp)
1431 {
1432         if (IS_ERR_OR_NULL(opp)) {
1433                 pr_err("%s: Invalid parameters\n", __func__);
1434                 return NULL;
1435         }
1436
1437         return of_node_get(opp->np);
1438 }
1439 EXPORT_SYMBOL_GPL(dev_pm_opp_get_of_node);
1440
1441 /*
1442  * Callback function provided to the Energy Model framework upon registration.
1443  * It provides the power used by @dev at @kHz if it is the frequency of an
1444  * existing OPP, or at the frequency of the first OPP above @kHz otherwise
1445  * (see dev_pm_opp_find_freq_ceil()). This function updates @kHz to the ceiled
1446  * frequency and @uW to the associated power.
1447  *
1448  * Returns 0 on success or a proper -EINVAL value in case of error.
1449  */
1450 static int __maybe_unused
1451 _get_dt_power(struct device *dev, unsigned long *uW, unsigned long *kHz)
1452 {
1453         struct dev_pm_opp *opp;
1454         unsigned long opp_freq, opp_power;
1455
1456         /* Find the right frequency and related OPP */
1457         opp_freq = *kHz * 1000;
1458         opp = dev_pm_opp_find_freq_ceil(dev, &opp_freq);
1459         if (IS_ERR(opp))
1460                 return -EINVAL;
1461
1462         opp_power = dev_pm_opp_get_power(opp);
1463         dev_pm_opp_put(opp);
1464         if (!opp_power)
1465                 return -EINVAL;
1466
1467         *kHz = opp_freq / 1000;
1468         *uW = opp_power;
1469
1470         return 0;
1471 }
1472
1473 /*
1474  * Callback function provided to the Energy Model framework upon registration.
1475  * This computes the power estimated by @dev at @kHz if it is the frequency
1476  * of an existing OPP, or at the frequency of the first OPP above @kHz otherwise
1477  * (see dev_pm_opp_find_freq_ceil()). This function updates @kHz to the ceiled
1478  * frequency and @uW to the associated power. The power is estimated as
1479  * P = C * V^2 * f with C being the device's capacitance and V and f
1480  * respectively the voltage and frequency of the OPP.
1481  *
1482  * Returns -EINVAL if the power calculation failed because of missing
1483  * parameters, 0 otherwise.
1484  */
1485 static int __maybe_unused _get_power(struct device *dev, unsigned long *uW,
1486                                      unsigned long *kHz)
1487 {
1488         struct dev_pm_opp *opp;
1489         struct device_node *np;
1490         unsigned long mV, Hz;
1491         u32 cap;
1492         u64 tmp;
1493         int ret;
1494
1495         np = of_node_get(dev->of_node);
1496         if (!np)
1497                 return -EINVAL;
1498
1499         ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1500         of_node_put(np);
1501         if (ret)
1502                 return -EINVAL;
1503
1504         Hz = *kHz * 1000;
1505         opp = dev_pm_opp_find_freq_ceil(dev, &Hz);
1506         if (IS_ERR(opp))
1507                 return -EINVAL;
1508
1509         mV = dev_pm_opp_get_voltage(opp) / 1000;
1510         dev_pm_opp_put(opp);
1511         if (!mV)
1512                 return -EINVAL;
1513
1514         tmp = (u64)cap * mV * mV * (Hz / 1000000);
1515         /* Provide power in micro-Watts */
1516         do_div(tmp, 1000000);
1517
1518         *uW = (unsigned long)tmp;
1519         *kHz = Hz / 1000;
1520
1521         return 0;
1522 }
1523
1524 static bool _of_has_opp_microwatt_property(struct device *dev)
1525 {
1526         unsigned long power, freq = 0;
1527         struct dev_pm_opp *opp;
1528
1529         /* Check if at least one OPP has needed property */
1530         opp = dev_pm_opp_find_freq_ceil(dev, &freq);
1531         if (IS_ERR(opp))
1532                 return false;
1533
1534         power = dev_pm_opp_get_power(opp);
1535         dev_pm_opp_put(opp);
1536         if (!power)
1537                 return false;
1538
1539         return true;
1540 }
1541
1542 /**
1543  * dev_pm_opp_of_register_em() - Attempt to register an Energy Model
1544  * @dev         : Device for which an Energy Model has to be registered
1545  * @cpus        : CPUs for which an Energy Model has to be registered. For
1546  *              other type of devices it should be set to NULL.
1547  *
1548  * This checks whether the "dynamic-power-coefficient" devicetree property has
1549  * been specified, and tries to register an Energy Model with it if it has.
1550  * Having this property means the voltages are known for OPPs and the EM
1551  * might be calculated.
1552  */
1553 int dev_pm_opp_of_register_em(struct device *dev, struct cpumask *cpus)
1554 {
1555         struct em_data_callback em_cb;
1556         struct device_node *np;
1557         int ret, nr_opp;
1558         u32 cap;
1559
1560         if (IS_ERR_OR_NULL(dev)) {
1561                 ret = -EINVAL;
1562                 goto failed;
1563         }
1564
1565         nr_opp = dev_pm_opp_get_opp_count(dev);
1566         if (nr_opp <= 0) {
1567                 ret = -EINVAL;
1568                 goto failed;
1569         }
1570
1571         /* First, try to find more precised Energy Model in DT */
1572         if (_of_has_opp_microwatt_property(dev)) {
1573                 EM_SET_ACTIVE_POWER_CB(em_cb, _get_dt_power);
1574                 goto register_em;
1575         }
1576
1577         np = of_node_get(dev->of_node);
1578         if (!np) {
1579                 ret = -EINVAL;
1580                 goto failed;
1581         }
1582
1583         /*
1584          * Register an EM only if the 'dynamic-power-coefficient' property is
1585          * set in devicetree. It is assumed the voltage values are known if that
1586          * property is set since it is useless otherwise. If voltages are not
1587          * known, just let the EM registration fail with an error to alert the
1588          * user about the inconsistent configuration.
1589          */
1590         ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1591         of_node_put(np);
1592         if (ret || !cap) {
1593                 dev_dbg(dev, "Couldn't find proper 'dynamic-power-coefficient' in DT\n");
1594                 ret = -EINVAL;
1595                 goto failed;
1596         }
1597
1598         EM_SET_ACTIVE_POWER_CB(em_cb, _get_power);
1599
1600 register_em:
1601         ret = em_dev_register_perf_domain(dev, nr_opp, &em_cb, cpus, true);
1602         if (ret)
1603                 goto failed;
1604
1605         return 0;
1606
1607 failed:
1608         dev_dbg(dev, "Couldn't register Energy Model %d\n", ret);
1609         return ret;
1610 }
1611 EXPORT_SYMBOL_GPL(dev_pm_opp_of_register_em);