drivers/opp/of.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Generic OPP OF helpers
   4  *
   5  * Copyright (C) 2009-2010 Texas Instruments Incorporated.
   6  *      Nishanth Menon
   7  *      Romit Dasgupta
   8  *      Kevin Hilman
   9  */
  10
  11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  12
  13 #include <linux/cpu.h>
  14 #include <linux/errno.h>
  15 #include <linux/device.h>
  16 #include <linux/of.h>
  17 #include <linux/pm_domain.h>
  18 #include <linux/slab.h>
  19 #include <linux/export.h>
  20 #include <linux/energy_model.h>
  21
  22 #include "opp.h"
  23
  24 /* OPP tables with uninitialized required OPPs, protected by opp_table_lock */
  25 static LIST_HEAD(lazy_opp_tables);
  26
  27 /*
  28  * Returns opp descriptor node for a device node, caller must
  29  * do of_node_put().
  30  */
  31 static struct device_node *_opp_of_get_opp_desc_node(struct device_node *np,
  32                                                      int index)
  33 {
  34         /* "operating-points-v2" can be an array for power domain providers */
  35         return of_parse_phandle(np, "operating-points-v2", index);
  36 }
  37
  38 /* Returns opp descriptor node for a device, caller must do of_node_put() */
  39 struct device_node *dev_pm_opp_of_get_opp_desc_node(struct device *dev)
  40 {
  41         return _opp_of_get_opp_desc_node(dev->of_node, 0);
  42 }
  43 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_opp_desc_node);
  44
  45 struct opp_table *_managed_opp(struct device *dev, int index)
  46 {
  47         struct opp_table *opp_table, *managed_table = NULL;
  48         struct device_node *np;
  49
  50         np = _opp_of_get_opp_desc_node(dev->of_node, index);
  51         if (!np)
  52                 return NULL;
  53
  54         list_for_each_entry(opp_table, &opp_tables, node) {
  55                 if (opp_table->np == np) {
  56                         /*
  57                          * Multiple devices can point to the same OPP table and
  58                          * so will have same node-pointer, np.
  59                          *
  60                          * But the OPPs will be considered as shared only if the
  61                          * OPP table contains a "opp-shared" property.
  62                          */
  63                         if (opp_table->shared_opp == OPP_TABLE_ACCESS_SHARED) {
  64                                 _get_opp_table_kref(opp_table);
  65                                 managed_table = opp_table;
  66                         }
  67
  68                         break;
  69                 }
  70         }
  71
  72         of_node_put(np);
  73
  74         return managed_table;
  75 }
  76
  77 /* The caller must call dev_pm_opp_put() after the OPP is used */
  78 static struct dev_pm_opp *_find_opp_of_np(struct opp_table *opp_table,
  79                                           struct device_node *opp_np)
  80 {
  81         struct dev_pm_opp *opp;
  82
  83         mutex_lock(&opp_table->lock);
  84
  85         list_for_each_entry(opp, &opp_table->opp_list, node) {
  86                 if (opp->np == opp_np) {
  87                         dev_pm_opp_get(opp);
  88                         mutex_unlock(&opp_table->lock);
  89                         return opp;
  90                 }
  91         }
  92
  93         mutex_unlock(&opp_table->lock);
  94
  95         return NULL;
  96 }
  97
  98 static struct device_node *of_parse_required_opp(struct device_node *np,
  99                                                  int index)
 100 {
 101         return of_parse_phandle(np, "required-opps", index);
 102 }
 103
 104 /* The caller must call dev_pm_opp_put_opp_table() after the table is used */
 105 static struct opp_table *_find_table_of_opp_np(struct device_node *opp_np)
 106 {
 107         struct opp_table *opp_table;
 108         struct device_node *opp_table_np;
 109
 110         opp_table_np = of_get_parent(opp_np);
 111         if (!opp_table_np)
 112                 goto err;
 113
 114         /* It is safe to put the node now as all we need now is its address */
 115         of_node_put(opp_table_np);
 116
 117         mutex_lock(&opp_table_lock);
 118         list_for_each_entry(opp_table, &opp_tables, node) {
 119                 if (opp_table_np == opp_table->np) {
 120                         _get_opp_table_kref(opp_table);
 121                         mutex_unlock(&opp_table_lock);
 122                         return opp_table;
 123                 }
 124         }
 125         mutex_unlock(&opp_table_lock);
 126
 127 err:
 128         return ERR_PTR(-ENODEV);
 129 }
 130
 131 /* Free resources previously acquired by _opp_table_alloc_required_tables() */
 132 static void _opp_table_free_required_tables(struct opp_table *opp_table)
 133 {
 134         struct opp_table **required_opp_tables = opp_table->required_opp_tables;
 135         int i;
 136
 137         if (!required_opp_tables)
 138                 return;
 139
 140         for (i = 0; i < opp_table->required_opp_count; i++) {
 141                 if (IS_ERR_OR_NULL(required_opp_tables[i]))
 142                         continue;
 143
 144                 dev_pm_opp_put_opp_table(required_opp_tables[i]);
 145         }
 146
 147         kfree(required_opp_tables);
 148
 149         opp_table->required_opp_count = 0;
 150         opp_table->required_opp_tables = NULL;
 151
 152         mutex_lock(&opp_table_lock);
 153         list_del(&opp_table->lazy);
 154         mutex_unlock(&opp_table_lock);
 155 }
 156
 157 /*
 158  * Populate all devices and opp tables which are part of "required-opps" list.
 159  * Checking only the first OPP node should be enough.
 160  */
 161 static void _opp_table_alloc_required_tables(struct opp_table *opp_table,
 162                                              struct device *dev,
 163                                              struct device_node *opp_np)
 164 {
 165         struct opp_table **required_opp_tables;
 166         struct device_node *required_np, *np;
 167         bool lazy = false;
 168         int count, i, size;
 169
 170         /* Traversing the first OPP node is all we need */
 171         np = of_get_next_available_child(opp_np, NULL);
 172         if (!np) {
 173                 dev_warn(dev, "Empty OPP table\n");
 174
 175                 return;
 176         }
 177
 178         count = of_count_phandle_with_args(np, "required-opps", NULL);
 179         if (count <= 0)
 180                 goto put_np;
 181
 182         size = sizeof(*required_opp_tables) + sizeof(*opp_table->required_devs);
 183         required_opp_tables = kcalloc(count, size, GFP_KERNEL);
 184         if (!required_opp_tables)
 185                 goto put_np;
 186
 187         opp_table->required_opp_tables = required_opp_tables;
 188         opp_table->required_devs = (void *)(required_opp_tables + count);
 189         opp_table->required_opp_count = count;
 190
 191         for (i = 0; i < count; i++) {
 192                 required_np = of_parse_required_opp(np, i);
 193                 if (!required_np)
 194                         goto free_required_tables;
 195
 196                 required_opp_tables[i] = _find_table_of_opp_np(required_np);
 197                 of_node_put(required_np);
 198
 199                 if (IS_ERR(required_opp_tables[i]))
 200                         lazy = true;
 201         }
 202
 203         /* Let's do the linking later on */
 204         if (lazy) {
 205                 /*
 206                  * The OPP table is not held while allocating the table, take it
 207                  * now to avoid corruption to the lazy_opp_tables list.
 208                  */
 209                 mutex_lock(&opp_table_lock);
 210                 list_add(&opp_table->lazy, &lazy_opp_tables);
 211                 mutex_unlock(&opp_table_lock);
 212         }
 213
 214         goto put_np;
 215
 216 free_required_tables:
 217         _opp_table_free_required_tables(opp_table);
 218 put_np:
 219         of_node_put(np);
 220 }
 221
 222 void _of_init_opp_table(struct opp_table *opp_table, struct device *dev,
 223                         int index)
 224 {
 225         struct device_node *np, *opp_np;
 226         u32 val;
 227
 228         /*
 229          * Only required for backward compatibility with v1 bindings, but isn't
 230          * harmful for other cases. And so we do it unconditionally.
 231          */
 232         np = of_node_get(dev->of_node);
 233         if (!np)
 234                 return;
 235
 236         if (!of_property_read_u32(np, "clock-latency", &val))
 237                 opp_table->clock_latency_ns_max = val;
 238         of_property_read_u32(np, "voltage-tolerance",
 239                              &opp_table->voltage_tolerance_v1);
 240
 241         if (of_property_present(np, "#power-domain-cells"))
 242                 opp_table->is_genpd = true;
 243
 244         /* Get OPP table node */
 245         opp_np = _opp_of_get_opp_desc_node(np, index);
 246         of_node_put(np);
 247
 248         if (!opp_np)
 249                 return;
 250
 251         if (of_property_read_bool(opp_np, "opp-shared"))
 252                 opp_table->shared_opp = OPP_TABLE_ACCESS_SHARED;
 253         else
 254                 opp_table->shared_opp = OPP_TABLE_ACCESS_EXCLUSIVE;
 255
 256         opp_table->np = opp_np;
 257
 258         _opp_table_alloc_required_tables(opp_table, dev, opp_np);
 259 }
 260
 261 void _of_clear_opp_table(struct opp_table *opp_table)
 262 {
 263         _opp_table_free_required_tables(opp_table);
 264         of_node_put(opp_table->np);
 265 }
 266
 267 /*
 268  * Release all resources previously acquired with a call to
 269  * _of_opp_alloc_required_opps().
 270  */
 271 static void _of_opp_free_required_opps(struct opp_table *opp_table,
 272                                        struct dev_pm_opp *opp)
 273 {
 274         struct dev_pm_opp **required_opps = opp->required_opps;
 275         int i;
 276
 277         if (!required_opps)
 278                 return;
 279
 280         for (i = 0; i < opp_table->required_opp_count; i++) {
 281                 if (!required_opps[i])
 282                         continue;
 283
 284                 /* Put the reference back */
 285                 dev_pm_opp_put(required_opps[i]);
 286         }
 287
 288         opp->required_opps = NULL;
 289         kfree(required_opps);
 290 }
 291
 292 void _of_clear_opp(struct opp_table *opp_table, struct dev_pm_opp *opp)
 293 {
 294         _of_opp_free_required_opps(opp_table, opp);
 295         of_node_put(opp->np);
 296 }
 297
 298 static int _link_required_opps(struct dev_pm_opp *opp, struct opp_table *opp_table,
 299                                struct opp_table *required_table, int index)
 300 {
 301         struct device_node *np;
 302
 303         np = of_parse_required_opp(opp->np, index);
 304         if (unlikely(!np))
 305                 return -ENODEV;
 306
 307         opp->required_opps[index] = _find_opp_of_np(required_table, np);
 308         of_node_put(np);
 309
 310         if (!opp->required_opps[index]) {
 311                 pr_err("%s: Unable to find required OPP node: %pOF (%d)\n",
 312                        __func__, opp->np, index);
 313                 return -ENODEV;
 314         }
 315
 316         /*
 317          * There are two genpd (as required-opp) cases that we need to handle,
 318          * devices with a single genpd and ones with multiple genpds.
 319          *
 320          * The single genpd case requires special handling as we need to use the
 321          * same `dev` structure (instead of a virtual one provided by genpd
 322          * core) for setting the performance state.
 323          *
 324          * It doesn't make sense for a device's DT entry to have both
 325          * "opp-level" and single "required-opps" entry pointing to a genpd's
 326          * OPP, as that would make the OPP core call
 327          * dev_pm_domain_set_performance_state() for two different values for
 328          * the same device structure. Lets treat single genpd configuration as a
 329          * case where the OPP's level is directly available without required-opp
 330          * link in the DT.
 331          *
 332          * Just update the `level` with the right value, which
 333          * dev_pm_opp_set_opp() will take care of in the normal path itself.
 334          *
 335          * There is another case though, where a genpd's OPP table has
 336          * required-opps set to a parent genpd. The OPP core expects the user to
 337          * set the respective required `struct device` pointer via
 338          * dev_pm_opp_set_config().
 339          */
 340         if (required_table->is_genpd && opp_table->required_opp_count == 1 &&
 341             !opp_table->required_devs[0]) {
 342                 /* Genpd core takes care of propagation to parent genpd */
 343                 if (!opp_table->is_genpd) {
 344                         if (!WARN_ON(opp->level != OPP_LEVEL_UNSET))
 345                                 opp->level = opp->required_opps[0]->level;
 346                 }
 347         }
 348
 349         return 0;
 350 }
 351
 352 /* Populate all required OPPs which are part of "required-opps" list */
 353 static int _of_opp_alloc_required_opps(struct opp_table *opp_table,
 354                                        struct dev_pm_opp *opp)
 355 {
 356         struct opp_table *required_table;
 357         int i, ret, count = opp_table->required_opp_count;
 358
 359         if (!count)
 360                 return 0;
 361
 362         opp->required_opps = kcalloc(count, sizeof(*opp->required_opps), GFP_KERNEL);
 363         if (!opp->required_opps)
 364                 return -ENOMEM;
 365
 366         for (i = 0; i < count; i++) {
 367                 required_table = opp_table->required_opp_tables[i];
 368
 369                 /* Required table not added yet, we will link later */
 370                 if (IS_ERR_OR_NULL(required_table))
 371                         continue;
 372
 373                 ret = _link_required_opps(opp, opp_table, required_table, i);
 374                 if (ret)
 375                         goto free_required_opps;
 376         }
 377
 378         return 0;
 379
 380 free_required_opps:
 381         _of_opp_free_required_opps(opp_table, opp);
 382
 383         return ret;
 384 }
 385
 386 /* Link required OPPs for an individual OPP */
 387 static int lazy_link_required_opps(struct opp_table *opp_table,
 388                                    struct opp_table *new_table, int index)
 389 {
 390         struct dev_pm_opp *opp;
 391         int ret;
 392
 393         list_for_each_entry(opp, &opp_table->opp_list, node) {
 394                 ret = _link_required_opps(opp, opp_table, new_table, index);
 395                 if (ret)
 396                         return ret;
 397         }
 398
 399         return 0;
 400 }
 401
 402 /* Link required OPPs for all OPPs of the newly added OPP table */
 403 static void lazy_link_required_opp_table(struct opp_table *new_table)
 404 {
 405         struct opp_table *opp_table, *temp, **required_opp_tables;
 406         struct device_node *required_np, *opp_np, *required_table_np;
 407         struct dev_pm_opp *opp;
 408         int i, ret;
 409
 410         mutex_lock(&opp_table_lock);
 411
 412         list_for_each_entry_safe(opp_table, temp, &lazy_opp_tables, lazy) {
 413                 bool lazy = false;
 414
 415                 /* opp_np can't be invalid here */
 416                 opp_np = of_get_next_available_child(opp_table->np, NULL);
 417
 418                 for (i = 0; i < opp_table->required_opp_count; i++) {
 419                         required_opp_tables = opp_table->required_opp_tables;
 420
 421                         /* Required opp-table is already parsed */
 422                         if (!IS_ERR(required_opp_tables[i]))
 423                                 continue;
 424
 425                         /* required_np can't be invalid here */
 426                         required_np = of_parse_required_opp(opp_np, i);
 427                         required_table_np = of_get_parent(required_np);
 428
 429                         of_node_put(required_table_np);
 430                         of_node_put(required_np);
 431
 432                         /*
 433                          * Newly added table isn't the required opp-table for
 434                          * opp_table.
 435                          */
 436                         if (required_table_np != new_table->np) {
 437                                 lazy = true;
 438                                 continue;
 439                         }
 440
 441                         required_opp_tables[i] = new_table;
 442                         _get_opp_table_kref(new_table);
 443
 444                         /* Link OPPs now */
 445                         ret = lazy_link_required_opps(opp_table, new_table, i);
 446                         if (ret) {
 447                                 /* The OPPs will be marked unusable */
 448                                 lazy = false;
 449                                 break;
 450                         }
 451                 }
 452
 453                 of_node_put(opp_np);
 454
 455                 /* All required opp-tables found, remove from lazy list */
 456                 if (!lazy) {
 457                         list_del_init(&opp_table->lazy);
 458
 459                         list_for_each_entry(opp, &opp_table->opp_list, node)
 460                                 _required_opps_available(opp, opp_table->required_opp_count);
 461                 }
 462         }
 463
 464         mutex_unlock(&opp_table_lock);
 465 }
 466
 467 static int _bandwidth_supported(struct device *dev, struct opp_table *opp_table)
 468 {
 469         struct device_node *np, *opp_np;
 470         struct property *prop;
 471
 472         if (!opp_table) {
 473                 np = of_node_get(dev->of_node);
 474                 if (!np)
 475                         return -ENODEV;
 476
 477                 opp_np = _opp_of_get_opp_desc_node(np, 0);
 478                 of_node_put(np);
 479         } else {
 480                 opp_np = of_node_get(opp_table->np);
 481         }
 482
 483         /* Lets not fail in case we are parsing opp-v1 bindings */
 484         if (!opp_np)
 485                 return 0;
 486
 487         /* Checking only first OPP is sufficient */
 488         np = of_get_next_available_child(opp_np, NULL);
 489         of_node_put(opp_np);
 490         if (!np) {
 491                 dev_err(dev, "OPP table empty\n");
 492                 return -EINVAL;
 493         }
 494
 495         prop = of_find_property(np, "opp-peak-kBps", NULL);
 496         of_node_put(np);
 497
 498         if (!prop || !prop->length)
 499                 return 0;
 500
 501         return 1;
 502 }
 503
 504 int dev_pm_opp_of_find_icc_paths(struct device *dev,
 505                                  struct opp_table *opp_table)
 506 {
 507         struct device_node *np;
 508         int ret, i, count, num_paths;
 509         struct icc_path **paths;
 510
 511         ret = _bandwidth_supported(dev, opp_table);
 512         if (ret == -EINVAL)
 513                 return 0; /* Empty OPP table is a valid corner-case, let's not fail */
 514         else if (ret <= 0)
 515                 return ret;
 516
 517         ret = 0;
 518
 519         np = of_node_get(dev->of_node);
 520         if (!np)
 521                 return 0;
 522
 523         count = of_count_phandle_with_args(np, "interconnects",
 524                                            "#interconnect-cells");
 525         of_node_put(np);
 526         if (count < 0)
 527                 return 0;
 528
 529         /* two phandles when #interconnect-cells = <1> */
 530         if (count % 2) {
 531                 dev_err(dev, "%s: Invalid interconnects values\n", __func__);
 532                 return -EINVAL;
 533         }
 534
 535         num_paths = count / 2;
 536         paths = kcalloc(num_paths, sizeof(*paths), GFP_KERNEL);
 537         if (!paths)
 538                 return -ENOMEM;
 539
 540         for (i = 0; i < num_paths; i++) {
 541                 paths[i] = of_icc_get_by_index(dev, i);
 542                 if (IS_ERR(paths[i])) {
 543                         ret = dev_err_probe(dev, PTR_ERR(paths[i]), "%s: Unable to get path%d\n", __func__, i);
 544                         goto err;
 545                 }
 546         }
 547
 548         if (opp_table) {
 549                 opp_table->paths = paths;
 550                 opp_table->path_count = num_paths;
 551                 return 0;
 552         }
 553
 554 err:
 555         while (i--)
 556                 icc_put(paths[i]);
 557
 558         kfree(paths);
 559
 560         return ret;
 561 }
 562 EXPORT_SYMBOL_GPL(dev_pm_opp_of_find_icc_paths);
 563
 564 static bool _opp_is_supported(struct device *dev, struct opp_table *opp_table,
 565                               struct device_node *np)
 566 {
 567         unsigned int levels = opp_table->supported_hw_count;
 568         int count, versions, ret, i, j;
 569         u32 val;
 570
 571         if (!opp_table->supported_hw) {
 572                 /*
 573                  * In the case that no supported_hw has been set by the
 574                  * platform but there is an opp-supported-hw value set for
 575                  * an OPP then the OPP should not be enabled as there is
 576                  * no way to see if the hardware supports it.
 577                  */
 578                 if (of_property_present(np, "opp-supported-hw"))
 579                         return false;
 580                 else
 581                         return true;
 582         }
 583
 584         count = of_property_count_u32_elems(np, "opp-supported-hw");
 585         if (count <= 0 || count % levels) {
 586                 dev_err(dev, "%s: Invalid opp-supported-hw property (%d)\n",
 587                         __func__, count);
 588                 return false;
 589         }
 590
 591         versions = count / levels;
 592
 593         /* All levels in at least one of the versions should match */
 594         for (i = 0; i < versions; i++) {
 595                 bool supported = true;
 596
 597                 for (j = 0; j < levels; j++) {
 598                         ret = of_property_read_u32_index(np, "opp-supported-hw",
 599                                                          i * levels + j, &val);
 600                         if (ret) {
 601                                 dev_warn(dev, "%s: failed to read opp-supported-hw property at index %d: %d\n",
 602                                          __func__, i * levels + j, ret);
 603                                 return false;
 604                         }
 605
 606                         /* Check if the level is supported */
 607                         if (!(val & opp_table->supported_hw[j])) {
 608                                 supported = false;
 609                                 break;
 610                         }
 611                 }
 612
 613                 if (supported)
 614                         return true;
 615         }
 616
 617         return false;
 618 }
 619
 620 static u32 *_parse_named_prop(struct dev_pm_opp *opp, struct device *dev,
 621                               struct opp_table *opp_table,
 622                               const char *prop_type, bool *triplet)
 623 {
 624         struct property *prop = NULL;
 625         char name[NAME_MAX];
 626         int count, ret;
 627         u32 *out;
 628
 629         /* Search for "opp-<prop_type>-<name>" */
 630         if (opp_table->prop_name) {
 631                 snprintf(name, sizeof(name), "opp-%s-%s", prop_type,
 632                          opp_table->prop_name);
 633                 prop = of_find_property(opp->np, name, NULL);
 634         }
 635
 636         if (!prop) {
 637                 /* Search for "opp-<prop_type>" */
 638                 snprintf(name, sizeof(name), "opp-%s", prop_type);
 639                 prop = of_find_property(opp->np, name, NULL);
 640                 if (!prop)
 641                         return NULL;
 642         }
 643
 644         count = of_property_count_u32_elems(opp->np, name);
 645         if (count < 0) {
 646                 dev_err(dev, "%s: Invalid %s property (%d)\n", __func__, name,
 647                         count);
 648                 return ERR_PTR(count);
 649         }
 650
 651         /*
 652          * Initialize regulator_count, if regulator information isn't provided
 653          * by the platform. Now that one of the properties is available, fix the
 654          * regulator_count to 1.
 655          */
 656         if (unlikely(opp_table->regulator_count == -1))
 657                 opp_table->regulator_count = 1;
 658
 659         if (count != opp_table->regulator_count &&
 660             (!triplet || count != opp_table->regulator_count * 3)) {
 661                 dev_err(dev, "%s: Invalid number of elements in %s property (%u) with supplies (%d)\n",
 662                         __func__, prop_type, count, opp_table->regulator_count);
 663                 return ERR_PTR(-EINVAL);
 664         }
 665
 666         out = kmalloc_array(count, sizeof(*out), GFP_KERNEL);
 667         if (!out)
 668                 return ERR_PTR(-EINVAL);
 669
 670         ret = of_property_read_u32_array(opp->np, name, out, count);
 671         if (ret) {
 672                 dev_err(dev, "%s: error parsing %s: %d\n", __func__, name, ret);
 673                 kfree(out);
 674                 return ERR_PTR(-EINVAL);
 675         }
 676
 677         if (triplet)
 678                 *triplet = count != opp_table->regulator_count;
 679
 680         return out;
 681 }
 682
 683 static u32 *opp_parse_microvolt(struct dev_pm_opp *opp, struct device *dev,
 684                                 struct opp_table *opp_table, bool *triplet)
 685 {
 686         u32 *microvolt;
 687
 688         microvolt = _parse_named_prop(opp, dev, opp_table, "microvolt", triplet);
 689         if (IS_ERR(microvolt))
 690                 return microvolt;
 691
 692         if (!microvolt) {
 693                 /*
 694                  * Missing property isn't a problem, but an invalid
 695                  * entry is. This property isn't optional if regulator
 696                  * information is provided. Check only for the first OPP, as
 697                  * regulator_count may get initialized after that to a valid
 698                  * value.
 699                  */
 700                 if (list_empty(&opp_table->opp_list) &&
 701                     opp_table->regulator_count > 0) {
 702                         dev_err(dev, "%s: opp-microvolt missing although OPP managing regulators\n",
 703                                 __func__);
 704                         return ERR_PTR(-EINVAL);
 705                 }
 706         }
 707
 708         return microvolt;
 709 }
 710
 711 static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,
 712                               struct opp_table *opp_table)
 713 {
 714         u32 *microvolt, *microamp, *microwatt;
 715         int ret = 0, i, j;
 716         bool triplet;
 717
 718         microvolt = opp_parse_microvolt(opp, dev, opp_table, &triplet);
 719         if (IS_ERR(microvolt))
 720                 return PTR_ERR(microvolt);
 721
 722         microamp = _parse_named_prop(opp, dev, opp_table, "microamp", NULL);
 723         if (IS_ERR(microamp)) {
 724                 ret = PTR_ERR(microamp);
 725                 goto free_microvolt;
 726         }
 727
 728         microwatt = _parse_named_prop(opp, dev, opp_table, "microwatt", NULL);
 729         if (IS_ERR(microwatt)) {
 730                 ret = PTR_ERR(microwatt);
 731                 goto free_microamp;
 732         }
 733
 734         /*
 735          * Initialize regulator_count if it is uninitialized and no properties
 736          * are found.
 737          */
 738         if (unlikely(opp_table->regulator_count == -1)) {
 739                 opp_table->regulator_count = 0;
 740                 return 0;
 741         }
 742
 743         for (i = 0, j = 0; i < opp_table->regulator_count; i++) {
 744                 if (microvolt) {
 745                         opp->supplies[i].u_volt = microvolt[j++];
 746
 747                         if (triplet) {
 748                                 opp->supplies[i].u_volt_min = microvolt[j++];
 749                                 opp->supplies[i].u_volt_max = microvolt[j++];
 750                         } else {
 751                                 opp->supplies[i].u_volt_min = opp->supplies[i].u_volt;
 752                                 opp->supplies[i].u_volt_max = opp->supplies[i].u_volt;
 753                         }
 754                 }
 755
 756                 if (microamp)
 757                         opp->supplies[i].u_amp = microamp[i];
 758
 759                 if (microwatt)
 760                         opp->supplies[i].u_watt = microwatt[i];
 761         }
 762
 763         kfree(microwatt);
 764 free_microamp:
 765         kfree(microamp);
 766 free_microvolt:
 767         kfree(microvolt);
 768
 769         return ret;
 770 }
 771
 772 /**
 773  * dev_pm_opp_of_remove_table() - Free OPP table entries created from static DT
 774  *                                entries
 775  * @dev:        device pointer used to lookup OPP table.
 776  *
 777  * Free OPPs created using static entries present in DT.
 778  */
 779 void dev_pm_opp_of_remove_table(struct device *dev)
 780 {
 781         dev_pm_opp_remove_table(dev);
 782 }
 783 EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table);
 784
 785 static int _read_rate(struct dev_pm_opp *new_opp, struct opp_table *opp_table,
 786                       struct device_node *np)
 787 {
 788         struct property *prop;
 789         int i, count, ret;
 790         u64 *rates;
 791
 792         prop = of_find_property(np, "opp-hz", NULL);
 793         if (!prop)
 794                 return -ENODEV;
 795
 796         count = prop->length / sizeof(u64);
 797         if (opp_table->clk_count != count) {
 798                 pr_err("%s: Count mismatch between opp-hz and clk_count (%d %d)\n",
 799                        __func__, count, opp_table->clk_count);
 800                 return -EINVAL;
 801         }
 802
 803         rates = kmalloc_array(count, sizeof(*rates), GFP_KERNEL);
 804         if (!rates)
 805                 return -ENOMEM;
 806
 807         ret = of_property_read_u64_array(np, "opp-hz", rates, count);
 808         if (ret) {
 809                 pr_err("%s: Error parsing opp-hz: %d\n", __func__, ret);
 810         } else {
 811                 /*
 812                  * Rate is defined as an unsigned long in clk API, and so
 813                  * casting explicitly to its type. Must be fixed once rate is 64
 814                  * bit guaranteed in clk API.
 815                  */
 816                 for (i = 0; i < count; i++) {
 817                         new_opp->rates[i] = (unsigned long)rates[i];
 818
 819                         /* This will happen for frequencies > 4.29 GHz */
 820                         WARN_ON(new_opp->rates[i] != rates[i]);
 821                 }
 822         }
 823
 824         kfree(rates);
 825
 826         return ret;
 827 }
 828
 829 static int _read_bw(struct dev_pm_opp *new_opp, struct opp_table *opp_table,
 830                     struct device_node *np, bool peak)
 831 {
 832         const char *name = peak ? "opp-peak-kBps" : "opp-avg-kBps";
 833         struct property *prop;
 834         int i, count, ret;
 835         u32 *bw;
 836
 837         prop = of_find_property(np, name, NULL);
 838         if (!prop)
 839                 return -ENODEV;
 840
 841         count = prop->length / sizeof(u32);
 842         if (opp_table->path_count != count) {
 843                 pr_err("%s: Mismatch between %s and paths (%d %d)\n",
 844                                 __func__, name, count, opp_table->path_count);
 845                 return -EINVAL;
 846         }
 847
 848         bw = kmalloc_array(count, sizeof(*bw), GFP_KERNEL);
 849         if (!bw)
 850                 return -ENOMEM;
 851
 852         ret = of_property_read_u32_array(np, name, bw, count);
 853         if (ret) {
 854                 pr_err("%s: Error parsing %s: %d\n", __func__, name, ret);
 855                 goto out;
 856         }
 857
 858         for (i = 0; i < count; i++) {
 859                 if (peak)
 860                         new_opp->bandwidth[i].peak = kBps_to_icc(bw[i]);
 861                 else
 862                         new_opp->bandwidth[i].avg = kBps_to_icc(bw[i]);
 863         }
 864
 865 out:
 866         kfree(bw);
 867         return ret;
 868 }
 869
 870 static int _read_opp_key(struct dev_pm_opp *new_opp,
 871                          struct opp_table *opp_table, struct device_node *np)
 872 {
 873         bool found = false;
 874         int ret;
 875
 876         ret = _read_rate(new_opp, opp_table, np);
 877         if (!ret)
 878                 found = true;
 879         else if (ret != -ENODEV)
 880                 return ret;
 881
 882         /*
 883          * Bandwidth consists of peak and average (optional) values:
 884          * opp-peak-kBps = <path1_value path2_value>;
 885          * opp-avg-kBps = <path1_value path2_value>;
 886          */
 887         ret = _read_bw(new_opp, opp_table, np, true);
 888         if (!ret) {
 889                 found = true;
 890                 ret = _read_bw(new_opp, opp_table, np, false);
 891         }
 892
 893         /* The properties were found but we failed to parse them */
 894         if (ret && ret != -ENODEV)
 895                 return ret;
 896
 897         if (!of_property_read_u32(np, "opp-level", &new_opp->level))
 898                 found = true;
 899
 900         if (found)
 901                 return 0;
 902
 903         return ret;
 904 }
 905
 906 /**
 907  * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings)
 908  * @opp_table:  OPP table
 909  * @dev:        device for which we do this operation
 910  * @np:         device node
 911  *
 912  * This function adds an opp definition to the opp table and returns status. The
 913  * opp can be controlled using dev_pm_opp_enable/disable functions and may be
 914  * removed by dev_pm_opp_remove.
 915  *
 916  * Return:
 917  * Valid OPP pointer:
 918  *              On success
 919  * NULL:
 920  *              Duplicate OPPs (both freq and volt are same) and opp->available
 921  *              OR if the OPP is not supported by hardware.
 922  * ERR_PTR(-EEXIST):
 923  *              Freq are same and volt are different OR
 924  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 925  * ERR_PTR(-ENOMEM):
 926  *              Memory allocation failure
 927  * ERR_PTR(-EINVAL):
 928  *              Failed parsing the OPP node
 929  */
 930 static struct dev_pm_opp *_opp_add_static_v2(struct opp_table *opp_table,
 931                 struct device *dev, struct device_node *np)
 932 {
 933         struct dev_pm_opp *new_opp;
 934         u32 val;
 935         int ret;
 936
 937         new_opp = _opp_allocate(opp_table);
 938         if (!new_opp)
 939                 return ERR_PTR(-ENOMEM);
 940
 941         ret = _read_opp_key(new_opp, opp_table, np);
 942         if (ret < 0) {
 943                 dev_err(dev, "%s: opp key field not found\n", __func__);
 944                 goto free_opp;
 945         }
 946
 947         /* Check if the OPP supports hardware's hierarchy of versions or not */
 948         if (!_opp_is_supported(dev, opp_table, np)) {
 949                 dev_dbg(dev, "OPP not supported by hardware: %s\n",
 950                         of_node_full_name(np));
 951                 goto free_opp;
 952         }
 953
 954         new_opp->turbo = of_property_read_bool(np, "turbo-mode");
 955
 956         new_opp->np = of_node_get(np);
 957         new_opp->dynamic = false;
 958         new_opp->available = true;
 959
 960         ret = _of_opp_alloc_required_opps(opp_table, new_opp);
 961         if (ret)
 962                 goto free_opp;
 963
 964         if (!of_property_read_u32(np, "clock-latency-ns", &val))
 965                 new_opp->clock_latency_ns = val;
 966
 967         ret = opp_parse_supplies(new_opp, dev, opp_table);
 968         if (ret)
 969                 goto free_required_opps;
 970
 971         ret = _opp_add(dev, new_opp, opp_table);
 972         if (ret) {
 973                 /* Don't return error for duplicate OPPs */
 974                 if (ret == -EBUSY)
 975                         ret = 0;
 976                 goto free_required_opps;
 977         }
 978
 979         /* OPP to select on device suspend */
 980         if (of_property_read_bool(np, "opp-suspend")) {
 981                 if (opp_table->suspend_opp) {
 982                         /* Pick the OPP with higher rate/bw/level as suspend OPP */
 983                         if (_opp_compare_key(opp_table, new_opp, opp_table->suspend_opp) == 1) {
 984                                 opp_table->suspend_opp->suspend = false;
 985                                 new_opp->suspend = true;
 986                                 opp_table->suspend_opp = new_opp;
 987                         }
 988                 } else {
 989                         new_opp->suspend = true;
 990                         opp_table->suspend_opp = new_opp;
 991                 }
 992         }
 993
 994         if (new_opp->clock_latency_ns > opp_table->clock_latency_ns_max)
 995                 opp_table->clock_latency_ns_max = new_opp->clock_latency_ns;
 996
 997         pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu level:%u\n",
 998                  __func__, new_opp->turbo, new_opp->rates[0],
 999                  new_opp->supplies[0].u_volt, new_opp->supplies[0].u_volt_min,
1000                  new_opp->supplies[0].u_volt_max, new_opp->clock_latency_ns,
1001                  new_opp->level);
1002
1003         /*
1004          * Notify the changes in the availability of the operable
1005          * frequency/voltage list.
1006          */
1007         blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ADD, new_opp);
1008         return new_opp;
1009
1010 free_required_opps:
1011         _of_opp_free_required_opps(opp_table, new_opp);
1012 free_opp:
1013         _opp_free(new_opp);
1014
1015         return ret ? ERR_PTR(ret) : NULL;
1016 }
1017
1018 /* Initializes OPP tables based on new bindings */
1019 static int _of_add_opp_table_v2(struct device *dev, struct opp_table *opp_table)
1020 {
1021         struct device_node *np;
1022         int ret, count = 0;
1023         struct dev_pm_opp *opp;
1024
1025         /* OPP table is already initialized for the device */
1026         mutex_lock(&opp_table->lock);
1027         if (opp_table->parsed_static_opps) {
1028                 opp_table->parsed_static_opps++;
1029                 mutex_unlock(&opp_table->lock);
1030                 return 0;
1031         }
1032
1033         opp_table->parsed_static_opps = 1;
1034         mutex_unlock(&opp_table->lock);
1035
1036         /* We have opp-table node now, iterate over it and add OPPs */
1037         for_each_available_child_of_node(opp_table->np, np) {
1038                 opp = _opp_add_static_v2(opp_table, dev, np);
1039                 if (IS_ERR(opp)) {
1040                         ret = PTR_ERR(opp);
1041                         dev_err(dev, "%s: Failed to add OPP, %d\n", __func__,
1042                                 ret);
1043                         of_node_put(np);
1044                         goto remove_static_opp;
1045                 } else if (opp) {
1046                         count++;
1047                 }
1048         }
1049
1050         /* There should be one or more OPPs defined */
1051         if (!count) {
1052                 dev_err(dev, "%s: no supported OPPs", __func__);
1053                 ret = -ENOENT;
1054                 goto remove_static_opp;
1055         }
1056
1057         lazy_link_required_opp_table(opp_table);
1058
1059         return 0;
1060
1061 remove_static_opp:
1062         _opp_remove_all_static(opp_table);
1063
1064         return ret;
1065 }
1066
1067 /* Initializes OPP tables based on old-deprecated bindings */
1068 static int _of_add_opp_table_v1(struct device *dev, struct opp_table *opp_table)
1069 {
1070         const struct property *prop;
1071         const __be32 *val;
1072         int nr, ret = 0;
1073
1074         mutex_lock(&opp_table->lock);
1075         if (opp_table->parsed_static_opps) {
1076                 opp_table->parsed_static_opps++;
1077                 mutex_unlock(&opp_table->lock);
1078                 return 0;
1079         }
1080
1081         opp_table->parsed_static_opps = 1;
1082         mutex_unlock(&opp_table->lock);
1083
1084         prop = of_find_property(dev->of_node, "operating-points", NULL);
1085         if (!prop) {
1086                 ret = -ENODEV;
1087                 goto remove_static_opp;
1088         }
1089         if (!prop->value) {
1090                 ret = -ENODATA;
1091                 goto remove_static_opp;
1092         }
1093
1094         /*
1095          * Each OPP is a set of tuples consisting of frequency and
1096          * voltage like <freq-kHz vol-uV>.
1097          */
1098         nr = prop->length / sizeof(u32);
1099         if (nr % 2) {
1100                 dev_err(dev, "%s: Invalid OPP table\n", __func__);
1101                 ret = -EINVAL;
1102                 goto remove_static_opp;
1103         }
1104
1105         val = prop->value;
1106         while (nr) {
1107                 unsigned long freq = be32_to_cpup(val++) * 1000;
1108                 unsigned long volt = be32_to_cpup(val++);
1109                 struct dev_pm_opp_data data = {
1110                         .freq = freq,
1111                         .u_volt = volt,
1112                 };
1113
1114                 ret = _opp_add_v1(opp_table, dev, &data, false);
1115                 if (ret) {
1116                         dev_err(dev, "%s: Failed to add OPP %ld (%d)\n",
1117                                 __func__, data.freq, ret);
1118                         goto remove_static_opp;
1119                 }
1120                 nr -= 2;
1121         }
1122
1123         return 0;
1124
1125 remove_static_opp:
1126         _opp_remove_all_static(opp_table);
1127
1128         return ret;
1129 }
1130
1131 static int _of_add_table_indexed(struct device *dev, int index)
1132 {
1133         struct opp_table *opp_table;
1134         int ret, count;
1135
1136         if (index) {
1137                 /*
1138                  * If only one phandle is present, then the same OPP table
1139                  * applies for all index requests.
1140                  */
1141                 count = of_count_phandle_with_args(dev->of_node,
1142                                                    "operating-points-v2", NULL);
1143                 if (count == 1)
1144                         index = 0;
1145         }
1146
1147         opp_table = _add_opp_table_indexed(dev, index, true);
1148         if (IS_ERR(opp_table))
1149                 return PTR_ERR(opp_table);
1150
1151         /*
1152          * OPPs have two version of bindings now. Also try the old (v1)
1153          * bindings for backward compatibility with older dtbs.
1154          */
1155         if (opp_table->np)
1156                 ret = _of_add_opp_table_v2(dev, opp_table);
1157         else
1158                 ret = _of_add_opp_table_v1(dev, opp_table);
1159
1160         if (ret)
1161                 dev_pm_opp_put_opp_table(opp_table);
1162
1163         return ret;
1164 }
1165
1166 static void devm_pm_opp_of_table_release(void *data)
1167 {
1168         dev_pm_opp_of_remove_table(data);
1169 }
1170
1171 static int _devm_of_add_table_indexed(struct device *dev, int index)
1172 {
1173         int ret;
1174
1175         ret = _of_add_table_indexed(dev, index);
1176         if (ret)
1177                 return ret;
1178
1179         return devm_add_action_or_reset(dev, devm_pm_opp_of_table_release, dev);
1180 }
1181
1182 /**
1183  * devm_pm_opp_of_add_table() - Initialize opp table from device tree
1184  * @dev:        device pointer used to lookup OPP table.
1185  *
1186  * Register the initial OPP table with the OPP library for given device.
1187  *
1188  * The opp_table structure will be freed after the device is destroyed.
1189  *
1190  * Return:
1191  * 0            On success OR
1192  *              Duplicate OPPs (both freq and volt are same) and opp->available
1193  * -EEXIST      Freq are same and volt are different OR
1194  *              Duplicate OPPs (both freq and volt are same) and !opp->available
1195  * -ENOMEM      Memory allocation failure
1196  * -ENODEV      when 'operating-points' property is not found or is invalid data
1197  *              in device node.
1198  * -ENODATA     when empty 'operating-points' property is found
1199  * -EINVAL      when invalid entries are found in opp-v2 table
1200  */
1201 int devm_pm_opp_of_add_table(struct device *dev)
1202 {
1203         return _devm_of_add_table_indexed(dev, 0);
1204 }
1205 EXPORT_SYMBOL_GPL(devm_pm_opp_of_add_table);
1206
1207 /**
1208  * dev_pm_opp_of_add_table() - Initialize opp table from device tree
1209  * @dev:        device pointer used to lookup OPP table.
1210  *
1211  * Register the initial OPP table with the OPP library for given device.
1212  *
1213  * Return:
1214  * 0            On success OR
1215  *              Duplicate OPPs (both freq and volt are same) and opp->available
1216  * -EEXIST      Freq are same and volt are different OR
1217  *              Duplicate OPPs (both freq and volt are same) and !opp->available
1218  * -ENOMEM      Memory allocation failure
1219  * -ENODEV      when 'operating-points' property is not found or is invalid data
1220  *              in device node.
1221  * -ENODATA     when empty 'operating-points' property is found
1222  * -EINVAL      when invalid entries are found in opp-v2 table
1223  */
1224 int dev_pm_opp_of_add_table(struct device *dev)
1225 {
1226         return _of_add_table_indexed(dev, 0);
1227 }
1228 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table);
1229
1230 /**
1231  * dev_pm_opp_of_add_table_indexed() - Initialize indexed opp table from device tree
1232  * @dev:        device pointer used to lookup OPP table.
1233  * @index:      Index number.
1234  *
1235  * Register the initial OPP table with the OPP library for given device only
1236  * using the "operating-points-v2" property.
1237  *
1238  * Return: Refer to dev_pm_opp_of_add_table() for return values.
1239  */
1240 int dev_pm_opp_of_add_table_indexed(struct device *dev, int index)
1241 {
1242         return _of_add_table_indexed(dev, index);
1243 }
1244 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table_indexed);
1245
1246 /**
1247  * devm_pm_opp_of_add_table_indexed() - Initialize indexed opp table from device tree
1248  * @dev:        device pointer used to lookup OPP table.
1249  * @index:      Index number.
1250  *
1251  * This is a resource-managed variant of dev_pm_opp_of_add_table_indexed().
1252  */
1253 int devm_pm_opp_of_add_table_indexed(struct device *dev, int index)
1254 {
1255         return _devm_of_add_table_indexed(dev, index);
1256 }
1257 EXPORT_SYMBOL_GPL(devm_pm_opp_of_add_table_indexed);
1258
1259 /* CPU device specific helpers */
1260
1261 /**
1262  * dev_pm_opp_of_cpumask_remove_table() - Removes OPP table for @cpumask
1263  * @cpumask:    cpumask for which OPP table needs to be removed
1264  *
1265  * This removes the OPP tables for CPUs present in the @cpumask.
1266  * This should be used only to remove static entries created from DT.
1267  */
1268 void dev_pm_opp_of_cpumask_remove_table(const struct cpumask *cpumask)
1269 {
1270         _dev_pm_opp_cpumask_remove_table(cpumask, -1);
1271 }
1272 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_remove_table);
1273
1274 /**
1275  * dev_pm_opp_of_cpumask_add_table() - Adds OPP table for @cpumask
1276  * @cpumask:    cpumask for which OPP table needs to be added.
1277  *
1278  * This adds the OPP tables for CPUs present in the @cpumask.
1279  */
1280 int dev_pm_opp_of_cpumask_add_table(const struct cpumask *cpumask)
1281 {
1282         struct device *cpu_dev;
1283         int cpu, ret;
1284
1285         if (WARN_ON(cpumask_empty(cpumask)))
1286                 return -ENODEV;
1287
1288         for_each_cpu(cpu, cpumask) {
1289                 cpu_dev = get_cpu_device(cpu);
1290                 if (!cpu_dev) {
1291                         pr_err("%s: failed to get cpu%d device\n", __func__,
1292                                cpu);
1293                         ret = -ENODEV;
1294                         goto remove_table;
1295                 }
1296
1297                 ret = dev_pm_opp_of_add_table(cpu_dev);
1298                 if (ret) {
1299                         /*
1300                          * OPP may get registered dynamically, don't print error
1301                          * message here.
1302                          */
1303                         pr_debug("%s: couldn't find opp table for cpu:%d, %d\n",
1304                                  __func__, cpu, ret);
1305
1306                         goto remove_table;
1307                 }
1308         }
1309
1310         return 0;
1311
1312 remove_table:
1313         /* Free all other OPPs */
1314         _dev_pm_opp_cpumask_remove_table(cpumask, cpu);
1315
1316         return ret;
1317 }
1318 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_add_table);
1319
1320 /*
1321  * Works only for OPP v2 bindings.
1322  *
1323  * Returns -ENOENT if operating-points-v2 bindings aren't supported.
1324  */
1325 /**
1326  * dev_pm_opp_of_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with
1327  *                                    @cpu_dev using operating-points-v2
1328  *                                    bindings.
1329  *
1330  * @cpu_dev:    CPU device for which we do this operation
1331  * @cpumask:    cpumask to update with information of sharing CPUs
1332  *
1333  * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev.
1334  *
1335  * Returns -ENOENT if operating-points-v2 isn't present for @cpu_dev.
1336  */
1337 int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev,
1338                                    struct cpumask *cpumask)
1339 {
1340         struct device_node *np, *tmp_np, *cpu_np;
1341         int cpu, ret = 0;
1342
1343         /* Get OPP descriptor node */
1344         np = dev_pm_opp_of_get_opp_desc_node(cpu_dev);
1345         if (!np) {
1346                 dev_dbg(cpu_dev, "%s: Couldn't find opp node.\n", __func__);
1347                 return -ENOENT;
1348         }
1349
1350         cpumask_set_cpu(cpu_dev->id, cpumask);
1351
1352         /* OPPs are shared ? */
1353         if (!of_property_read_bool(np, "opp-shared"))
1354                 goto put_cpu_node;
1355
1356         for_each_possible_cpu(cpu) {
1357                 if (cpu == cpu_dev->id)
1358                         continue;
1359
1360                 cpu_np = of_cpu_device_node_get(cpu);
1361                 if (!cpu_np) {
1362                         dev_err(cpu_dev, "%s: failed to get cpu%d node\n",
1363                                 __func__, cpu);
1364                         ret = -ENOENT;
1365                         goto put_cpu_node;
1366                 }
1367
1368                 /* Get OPP descriptor node */
1369                 tmp_np = _opp_of_get_opp_desc_node(cpu_np, 0);
1370                 of_node_put(cpu_np);
1371                 if (!tmp_np) {
1372                         pr_err("%pOF: Couldn't find opp node\n", cpu_np);
1373                         ret = -ENOENT;
1374                         goto put_cpu_node;
1375                 }
1376
1377                 /* CPUs are sharing opp node */
1378                 if (np == tmp_np)
1379                         cpumask_set_cpu(cpu, cpumask);
1380
1381                 of_node_put(tmp_np);
1382         }
1383
1384 put_cpu_node:
1385         of_node_put(np);
1386         return ret;
1387 }
1388 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus);
1389
1390 /**
1391  * of_get_required_opp_performance_state() - Search for required OPP and return its performance state.
1392  * @np: Node that contains the "required-opps" property.
1393  * @index: Index of the phandle to parse.
1394  *
1395  * Returns the performance state of the OPP pointed out by the "required-opps"
1396  * property at @index in @np.
1397  *
1398  * Return: Zero or positive performance state on success, otherwise negative
1399  * value on errors.
1400  */
1401 int of_get_required_opp_performance_state(struct device_node *np, int index)
1402 {
1403         struct dev_pm_opp *opp;
1404         struct device_node *required_np;
1405         struct opp_table *opp_table;
1406         int pstate = -EINVAL;
1407
1408         required_np = of_parse_required_opp(np, index);
1409         if (!required_np)
1410                 return -ENODEV;
1411
1412         opp_table = _find_table_of_opp_np(required_np);
1413         if (IS_ERR(opp_table)) {
1414                 pr_err("%s: Failed to find required OPP table %pOF: %ld\n",
1415                        __func__, np, PTR_ERR(opp_table));
1416                 goto put_required_np;
1417         }
1418
1419         /* The OPP tables must belong to a genpd */
1420         if (unlikely(!opp_table->is_genpd)) {
1421                 pr_err("%s: Performance state is only valid for genpds.\n", __func__);
1422                 goto put_required_np;
1423         }
1424
1425         opp = _find_opp_of_np(opp_table, required_np);
1426         if (opp) {
1427                 if (opp->level == OPP_LEVEL_UNSET) {
1428                         pr_err("%s: OPP levels aren't available for %pOF\n",
1429                                __func__, np);
1430                 } else {
1431                         pstate = opp->level;
1432                 }
1433                 dev_pm_opp_put(opp);
1434
1435         }
1436
1437         dev_pm_opp_put_opp_table(opp_table);
1438
1439 put_required_np:
1440         of_node_put(required_np);
1441
1442         return pstate;
1443 }
1444 EXPORT_SYMBOL_GPL(of_get_required_opp_performance_state);
1445
1446 /**
1447  * dev_pm_opp_get_of_node() - Gets the DT node corresponding to an opp
1448  * @opp:        opp for which DT node has to be returned for
1449  *
1450  * Return: DT node corresponding to the opp, else 0 on success.
1451  *
1452  * The caller needs to put the node with of_node_put() after using it.
1453  */
1454 struct device_node *dev_pm_opp_get_of_node(struct dev_pm_opp *opp)
1455 {
1456         if (IS_ERR_OR_NULL(opp)) {
1457                 pr_err("%s: Invalid parameters\n", __func__);
1458                 return NULL;
1459         }
1460
1461         return of_node_get(opp->np);
1462 }
1463 EXPORT_SYMBOL_GPL(dev_pm_opp_get_of_node);
1464
1465 /*
1466  * Callback function provided to the Energy Model framework upon registration.
1467  * It provides the power used by @dev at @kHz if it is the frequency of an
1468  * existing OPP, or at the frequency of the first OPP above @kHz otherwise
1469  * (see dev_pm_opp_find_freq_ceil()). This function updates @kHz to the ceiled
1470  * frequency and @uW to the associated power.
1471  *
1472  * Returns 0 on success or a proper -EINVAL value in case of error.
1473  */
1474 static int __maybe_unused
1475 _get_dt_power(struct device *dev, unsigned long *uW, unsigned long *kHz)
1476 {
1477         struct dev_pm_opp *opp;
1478         unsigned long opp_freq, opp_power;
1479
1480         /* Find the right frequency and related OPP */
1481         opp_freq = *kHz * 1000;
1482         opp = dev_pm_opp_find_freq_ceil(dev, &opp_freq);
1483         if (IS_ERR(opp))
1484                 return -EINVAL;
1485
1486         opp_power = dev_pm_opp_get_power(opp);
1487         dev_pm_opp_put(opp);
1488         if (!opp_power)
1489                 return -EINVAL;
1490
1491         *kHz = opp_freq / 1000;
1492         *uW = opp_power;
1493
1494         return 0;
1495 }
1496
1497 /*
1498  * Callback function provided to the Energy Model framework upon registration.
1499  * This computes the power estimated by @dev at @kHz if it is the frequency
1500  * of an existing OPP, or at the frequency of the first OPP above @kHz otherwise
1501  * (see dev_pm_opp_find_freq_ceil()). This function updates @kHz to the ceiled
1502  * frequency and @uW to the associated power. The power is estimated as
1503  * P = C * V^2 * f with C being the device's capacitance and V and f
1504  * respectively the voltage and frequency of the OPP.
1505  *
1506  * Returns -EINVAL if the power calculation failed because of missing
1507  * parameters, 0 otherwise.
1508  */
1509 static int __maybe_unused _get_power(struct device *dev, unsigned long *uW,
1510                                      unsigned long *kHz)
1511 {
1512         struct dev_pm_opp *opp;
1513         struct device_node *np;
1514         unsigned long mV, Hz;
1515         u32 cap;
1516         u64 tmp;
1517         int ret;
1518
1519         np = of_node_get(dev->of_node);
1520         if (!np)
1521                 return -EINVAL;
1522
1523         ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1524         of_node_put(np);
1525         if (ret)
1526                 return -EINVAL;
1527
1528         Hz = *kHz * 1000;
1529         opp = dev_pm_opp_find_freq_ceil(dev, &Hz);
1530         if (IS_ERR(opp))
1531                 return -EINVAL;
1532
1533         mV = dev_pm_opp_get_voltage(opp) / 1000;
1534         dev_pm_opp_put(opp);
1535         if (!mV)
1536                 return -EINVAL;
1537
1538         tmp = (u64)cap * mV * mV * (Hz / 1000000);
1539         /* Provide power in micro-Watts */
1540         do_div(tmp, 1000000);
1541
1542         *uW = (unsigned long)tmp;
1543         *kHz = Hz / 1000;
1544
1545         return 0;
1546 }
1547
1548 static bool _of_has_opp_microwatt_property(struct device *dev)
1549 {
1550         unsigned long power, freq = 0;
1551         struct dev_pm_opp *opp;
1552
1553         /* Check if at least one OPP has needed property */
1554         opp = dev_pm_opp_find_freq_ceil(dev, &freq);
1555         if (IS_ERR(opp))
1556                 return false;
1557
1558         power = dev_pm_opp_get_power(opp);
1559         dev_pm_opp_put(opp);
1560         if (!power)
1561                 return false;
1562
1563         return true;
1564 }
1565
1566 /**
1567  * dev_pm_opp_of_register_em() - Attempt to register an Energy Model
1568  * @dev         : Device for which an Energy Model has to be registered
1569  * @cpus        : CPUs for which an Energy Model has to be registered. For
1570  *              other type of devices it should be set to NULL.
1571  *
1572  * This checks whether the "dynamic-power-coefficient" devicetree property has
1573  * been specified, and tries to register an Energy Model with it if it has.
1574  * Having this property means the voltages are known for OPPs and the EM
1575  * might be calculated.
1576  */
1577 int dev_pm_opp_of_register_em(struct device *dev, struct cpumask *cpus)
1578 {
1579         struct em_data_callback em_cb;
1580         struct device_node *np;
1581         int ret, nr_opp;
1582         u32 cap;
1583
1584         if (IS_ERR_OR_NULL(dev)) {
1585                 ret = -EINVAL;
1586                 goto failed;
1587         }
1588
1589         nr_opp = dev_pm_opp_get_opp_count(dev);
1590         if (nr_opp <= 0) {
1591                 ret = -EINVAL;
1592                 goto failed;
1593         }
1594
1595         /* First, try to find more precised Energy Model in DT */
1596         if (_of_has_opp_microwatt_property(dev)) {
1597                 EM_SET_ACTIVE_POWER_CB(em_cb, _get_dt_power);
1598                 goto register_em;
1599         }
1600
1601         np = of_node_get(dev->of_node);
1602         if (!np) {
1603                 ret = -EINVAL;
1604                 goto failed;
1605         }
1606
1607         /*
1608          * Register an EM only if the 'dynamic-power-coefficient' property is
1609          * set in devicetree. It is assumed the voltage values are known if that
1610          * property is set since it is useless otherwise. If voltages are not
1611          * known, just let the EM registration fail with an error to alert the
1612          * user about the inconsistent configuration.
1613          */
1614         ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1615         of_node_put(np);
1616         if (ret || !cap) {
1617                 dev_dbg(dev, "Couldn't find proper 'dynamic-power-coefficient' in DT\n");
1618                 ret = -EINVAL;
1619                 goto failed;
1620         }
1621
1622         EM_SET_ACTIVE_POWER_CB(em_cb, _get_power);
1623
1624 register_em:
1625         ret = em_dev_register_perf_domain(dev, nr_opp, &em_cb, cpus, true);
1626         if (ret)
1627                 goto failed;
1628
1629         return 0;
1630
1631 failed:
1632         dev_dbg(dev, "Couldn't register Energy Model %d\n", ret);
1633         return ret;
1634 }
1635 EXPORT_SYMBOL_GPL(dev_pm_opp_of_register_em);