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