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         lockdep_assert_held(&opp_table_lock);
  81
  82         mutex_lock(&opp_table->lock);
  83
  84         list_for_each_entry(opp, &opp_table->opp_list, node) {
  85                 if (opp->np == opp_np) {
  86                         dev_pm_opp_get(opp);
  87                         mutex_unlock(&opp_table->lock);
  88                         return opp;
  89                 }
  90         }
  91
  92         mutex_unlock(&opp_table->lock);
  93
  94         return NULL;
  95 }
  96
  97 static struct device_node *of_parse_required_opp(struct device_node *np,
  98                                                  int index)
  99 {
 100         struct device_node *required_np;
 101
 102         required_np = of_parse_phandle(np, "required-opps", index);
 103         if (unlikely(!required_np)) {
 104                 pr_err("%s: Unable to parse required-opps: %pOF, index: %d\n",
 105                        __func__, np, index);
 106         }
 107
 108         return required_np;
 109 }
 110
 111 /* The caller must call dev_pm_opp_put_opp_table() after the table is used */
 112 static struct opp_table *_find_table_of_opp_np(struct device_node *opp_np)
 113 {
 114         struct opp_table *opp_table;
 115         struct device_node *opp_table_np;
 116
 117         lockdep_assert_held(&opp_table_lock);
 118
 119         opp_table_np = of_get_parent(opp_np);
 120         if (!opp_table_np)
 121                 goto err;
 122
 123         /* It is safe to put the node now as all we need now is its address */
 124         of_node_put(opp_table_np);
 125
 126         list_for_each_entry(opp_table, &opp_tables, node) {
 127                 if (opp_table_np == opp_table->np) {
 128                         _get_opp_table_kref(opp_table);
 129                         return opp_table;
 130                 }
 131         }
 132
 133 err:
 134         return ERR_PTR(-ENODEV);
 135 }
 136
 137 /* Free resources previously acquired by _opp_table_alloc_required_tables() */
 138 static void _opp_table_free_required_tables(struct opp_table *opp_table)
 139 {
 140         struct opp_table **required_opp_tables = opp_table->required_opp_tables;
 141         int i;
 142
 143         if (!required_opp_tables)
 144                 return;
 145
 146         for (i = 0; i < opp_table->required_opp_count; i++) {
 147                 if (IS_ERR_OR_NULL(required_opp_tables[i]))
 148                         break;
 149
 150                 dev_pm_opp_put_opp_table(required_opp_tables[i]);
 151         }
 152
 153         kfree(required_opp_tables);
 154
 155         opp_table->required_opp_count = 0;
 156         opp_table->required_opp_tables = NULL;
 157 }
 158
 159 /*
 160  * Populate all devices and opp tables which are part of "required-opps" list.
 161  * Checking only the first OPP node should be enough.
 162  */
 163 static void _opp_table_alloc_required_tables(struct opp_table *opp_table,
 164                                              struct device *dev,
 165                                              struct device_node *opp_np)
 166 {
 167         struct opp_table **required_opp_tables;
 168         struct device_node *required_np, *np;
 169         int count, i;
 170
 171         /* Traversing the first OPP node is all we need */
 172         np = of_get_next_available_child(opp_np, NULL);
 173         if (!np) {
 174                 dev_err(dev, "Empty OPP table\n");
 175                 return;
 176         }
 177
 178         count = of_count_phandle_with_args(np, "required-opps", NULL);
 179         if (!count)
 180                 goto put_np;
 181
 182         required_opp_tables = kcalloc(count, sizeof(*required_opp_tables),
 183                                       GFP_KERNEL);
 184         if (!required_opp_tables)
 185                 goto put_np;
 186
 187         opp_table->required_opp_tables = required_opp_tables;
 188         opp_table->required_opp_count = count;
 189
 190         for (i = 0; i < count; i++) {
 191                 required_np = of_parse_required_opp(np, i);
 192                 if (!required_np)
 193                         goto free_required_tables;
 194
 195                 required_opp_tables[i] = _find_table_of_opp_np(required_np);
 196                 of_node_put(required_np);
 197
 198                 if (IS_ERR(required_opp_tables[i]))
 199                         goto free_required_tables;
 200
 201                 /*
 202                  * We only support genpd's OPPs in the "required-opps" for now,
 203                  * as we don't know how much about other cases. Error out if the
 204                  * required OPP doesn't belong to a genpd.
 205                  */
 206                 if (!required_opp_tables[i]->is_genpd) {
 207                         dev_err(dev, "required-opp doesn't belong to genpd: %pOF\n",
 208                                 required_np);
 209                         goto free_required_tables;
 210                 }
 211         }
 212
 213         goto put_np;
 214
 215 free_required_tables:
 216         _opp_table_free_required_tables(opp_table);
 217 put_np:
 218         of_node_put(np);
 219 }
 220
 221 void _of_init_opp_table(struct opp_table *opp_table, struct device *dev,
 222                         int index)
 223 {
 224         struct device_node *np, *opp_np;
 225         u32 val;
 226
 227         /*
 228          * Only required for backward compatibility with v1 bindings, but isn't
 229          * harmful for other cases. And so we do it unconditionally.
 230          */
 231         np = of_node_get(dev->of_node);
 232         if (!np)
 233                 return;
 234
 235         if (!of_property_read_u32(np, "clock-latency", &val))
 236                 opp_table->clock_latency_ns_max = val;
 237         of_property_read_u32(np, "voltage-tolerance",
 238                              &opp_table->voltage_tolerance_v1);
 239
 240         if (of_find_property(np, "#power-domain-cells", NULL))
 241                 opp_table->is_genpd = true;
 242
 243         /* Get OPP table node */
 244         opp_np = _opp_of_get_opp_desc_node(np, index);
 245         of_node_put(np);
 246
 247         if (!opp_np)
 248                 return;
 249
 250         if (of_property_read_bool(opp_np, "opp-shared"))
 251                 opp_table->shared_opp = OPP_TABLE_ACCESS_SHARED;
 252         else
 253                 opp_table->shared_opp = OPP_TABLE_ACCESS_EXCLUSIVE;
 254
 255         opp_table->np = opp_np;
 256
 257         _opp_table_alloc_required_tables(opp_table, dev, opp_np);
 258         of_node_put(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 }
 265
 266 /*
 267  * Release all resources previously acquired with a call to
 268  * _of_opp_alloc_required_opps().
 269  */
 270 void _of_opp_free_required_opps(struct opp_table *opp_table,
 271                                 struct dev_pm_opp *opp)
 272 {
 273         struct dev_pm_opp **required_opps = opp->required_opps;
 274         int i;
 275
 276         if (!required_opps)
 277                 return;
 278
 279         for (i = 0; i < opp_table->required_opp_count; i++) {
 280                 if (!required_opps[i])
 281                         break;
 282
 283                 /* Put the reference back */
 284                 dev_pm_opp_put(required_opps[i]);
 285         }
 286
 287         kfree(required_opps);
 288         opp->required_opps = NULL;
 289 }
 290
 291 /* Populate all required OPPs which are part of "required-opps" list */
 292 static int _of_opp_alloc_required_opps(struct opp_table *opp_table,
 293                                        struct dev_pm_opp *opp)
 294 {
 295         struct dev_pm_opp **required_opps;
 296         struct opp_table *required_table;
 297         struct device_node *np;
 298         int i, ret, count = opp_table->required_opp_count;
 299
 300         if (!count)
 301                 return 0;
 302
 303         required_opps = kcalloc(count, sizeof(*required_opps), GFP_KERNEL);
 304         if (!required_opps)
 305                 return -ENOMEM;
 306
 307         opp->required_opps = required_opps;
 308
 309         for (i = 0; i < count; i++) {
 310                 required_table = opp_table->required_opp_tables[i];
 311
 312                 np = of_parse_required_opp(opp->np, i);
 313                 if (unlikely(!np)) {
 314                         ret = -ENODEV;
 315                         goto free_required_opps;
 316                 }
 317
 318                 required_opps[i] = _find_opp_of_np(required_table, np);
 319                 of_node_put(np);
 320
 321                 if (!required_opps[i]) {
 322                         pr_err("%s: Unable to find required OPP node: %pOF (%d)\n",
 323                                __func__, opp->np, i);
 324                         ret = -ENODEV;
 325                         goto free_required_opps;
 326                 }
 327         }
 328
 329         return 0;
 330
 331 free_required_opps:
 332         _of_opp_free_required_opps(opp_table, opp);
 333
 334         return ret;
 335 }
 336
 337 static bool _opp_is_supported(struct device *dev, struct opp_table *opp_table,
 338                               struct device_node *np)
 339 {
 340         unsigned int count = opp_table->supported_hw_count;
 341         u32 version;
 342         int ret;
 343
 344         if (!opp_table->supported_hw) {
 345                 /*
 346                  * In the case that no supported_hw has been set by the
 347                  * platform but there is an opp-supported-hw value set for
 348                  * an OPP then the OPP should not be enabled as there is
 349                  * no way to see if the hardware supports it.
 350                  */
 351                 if (of_find_property(np, "opp-supported-hw", NULL))
 352                         return false;
 353                 else
 354                         return true;
 355         }
 356
 357         while (count--) {
 358                 ret = of_property_read_u32_index(np, "opp-supported-hw", count,
 359                                                  &version);
 360                 if (ret) {
 361                         dev_warn(dev, "%s: failed to read opp-supported-hw property at index %d: %d\n",
 362                                  __func__, count, ret);
 363                         return false;
 364                 }
 365
 366                 /* Both of these are bitwise masks of the versions */
 367                 if (!(version & opp_table->supported_hw[count]))
 368                         return false;
 369         }
 370
 371         return true;
 372 }
 373
 374 static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,
 375                               struct opp_table *opp_table)
 376 {
 377         u32 *microvolt, *microamp = NULL;
 378         int supplies = opp_table->regulator_count, vcount, icount, ret, i, j;
 379         struct property *prop = NULL;
 380         char name[NAME_MAX];
 381
 382         /* Search for "opp-microvolt-<name>" */
 383         if (opp_table->prop_name) {
 384                 snprintf(name, sizeof(name), "opp-microvolt-%s",
 385                          opp_table->prop_name);
 386                 prop = of_find_property(opp->np, name, NULL);
 387         }
 388
 389         if (!prop) {
 390                 /* Search for "opp-microvolt" */
 391                 sprintf(name, "opp-microvolt");
 392                 prop = of_find_property(opp->np, name, NULL);
 393
 394                 /* Missing property isn't a problem, but an invalid entry is */
 395                 if (!prop) {
 396                         if (unlikely(supplies == -1)) {
 397                                 /* Initialize regulator_count */
 398                                 opp_table->regulator_count = 0;
 399                                 return 0;
 400                         }
 401
 402                         if (!supplies)
 403                                 return 0;
 404
 405                         dev_err(dev, "%s: opp-microvolt missing although OPP managing regulators\n",
 406                                 __func__);
 407                         return -EINVAL;
 408                 }
 409         }
 410
 411         if (unlikely(supplies == -1)) {
 412                 /* Initialize regulator_count */
 413                 supplies = opp_table->regulator_count = 1;
 414         } else if (unlikely(!supplies)) {
 415                 dev_err(dev, "%s: opp-microvolt wasn't expected\n", __func__);
 416                 return -EINVAL;
 417         }
 418
 419         vcount = of_property_count_u32_elems(opp->np, name);
 420         if (vcount < 0) {
 421                 dev_err(dev, "%s: Invalid %s property (%d)\n",
 422                         __func__, name, vcount);
 423                 return vcount;
 424         }
 425
 426         /* There can be one or three elements per supply */
 427         if (vcount != supplies && vcount != supplies * 3) {
 428                 dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
 429                         __func__, name, vcount, supplies);
 430                 return -EINVAL;
 431         }
 432
 433         microvolt = kmalloc_array(vcount, sizeof(*microvolt), GFP_KERNEL);
 434         if (!microvolt)
 435                 return -ENOMEM;
 436
 437         ret = of_property_read_u32_array(opp->np, name, microvolt, vcount);
 438         if (ret) {
 439                 dev_err(dev, "%s: error parsing %s: %d\n", __func__, name, ret);
 440                 ret = -EINVAL;
 441                 goto free_microvolt;
 442         }
 443
 444         /* Search for "opp-microamp-<name>" */
 445         prop = NULL;
 446         if (opp_table->prop_name) {
 447                 snprintf(name, sizeof(name), "opp-microamp-%s",
 448                          opp_table->prop_name);
 449                 prop = of_find_property(opp->np, name, NULL);
 450         }
 451
 452         if (!prop) {
 453                 /* Search for "opp-microamp" */
 454                 sprintf(name, "opp-microamp");
 455                 prop = of_find_property(opp->np, name, NULL);
 456         }
 457
 458         if (prop) {
 459                 icount = of_property_count_u32_elems(opp->np, name);
 460                 if (icount < 0) {
 461                         dev_err(dev, "%s: Invalid %s property (%d)\n", __func__,
 462                                 name, icount);
 463                         ret = icount;
 464                         goto free_microvolt;
 465                 }
 466
 467                 if (icount != supplies) {
 468                         dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
 469                                 __func__, name, icount, supplies);
 470                         ret = -EINVAL;
 471                         goto free_microvolt;
 472                 }
 473
 474                 microamp = kmalloc_array(icount, sizeof(*microamp), GFP_KERNEL);
 475                 if (!microamp) {
 476                         ret = -EINVAL;
 477                         goto free_microvolt;
 478                 }
 479
 480                 ret = of_property_read_u32_array(opp->np, name, microamp,
 481                                                  icount);
 482                 if (ret) {
 483                         dev_err(dev, "%s: error parsing %s: %d\n", __func__,
 484                                 name, ret);
 485                         ret = -EINVAL;
 486                         goto free_microamp;
 487                 }
 488         }
 489
 490         for (i = 0, j = 0; i < supplies; i++) {
 491                 opp->supplies[i].u_volt = microvolt[j++];
 492
 493                 if (vcount == supplies) {
 494                         opp->supplies[i].u_volt_min = opp->supplies[i].u_volt;
 495                         opp->supplies[i].u_volt_max = opp->supplies[i].u_volt;
 496                 } else {
 497                         opp->supplies[i].u_volt_min = microvolt[j++];
 498                         opp->supplies[i].u_volt_max = microvolt[j++];
 499                 }
 500
 501                 if (microamp)
 502                         opp->supplies[i].u_amp = microamp[i];
 503         }
 504
 505 free_microamp:
 506         kfree(microamp);
 507 free_microvolt:
 508         kfree(microvolt);
 509
 510         return ret;
 511 }
 512
 513 /**
 514  * dev_pm_opp_of_remove_table() - Free OPP table entries created from static DT
 515  *                                entries
 516  * @dev:        device pointer used to lookup OPP table.
 517  *
 518  * Free OPPs created using static entries present in DT.
 519  */
 520 void dev_pm_opp_of_remove_table(struct device *dev)
 521 {
 522         _dev_pm_opp_find_and_remove_table(dev);
 523 }
 524 EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table);
 525
 526 /**
 527  * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings)
 528  * @opp_table:  OPP table
 529  * @dev:        device for which we do this operation
 530  * @np:         device node
 531  *
 532  * This function adds an opp definition to the opp table and returns status. The
 533  * opp can be controlled using dev_pm_opp_enable/disable functions and may be
 534  * removed by dev_pm_opp_remove.
 535  *
 536  * Return:
 537  * Valid OPP pointer:
 538  *              On success
 539  * NULL:
 540  *              Duplicate OPPs (both freq and volt are same) and opp->available
 541  *              OR if the OPP is not supported by hardware.
 542  * ERR_PTR(-EEXIST):
 543  *              Freq are same and volt are different OR
 544  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 545  * ERR_PTR(-ENOMEM):
 546  *              Memory allocation failure
 547  * ERR_PTR(-EINVAL):
 548  *              Failed parsing the OPP node
 549  */
 550 static struct dev_pm_opp *_opp_add_static_v2(struct opp_table *opp_table,
 551                 struct device *dev, struct device_node *np)
 552 {
 553         struct dev_pm_opp *new_opp;
 554         u64 rate = 0;
 555         u32 val;
 556         int ret;
 557         bool rate_not_available = false;
 558
 559         new_opp = _opp_allocate(opp_table);
 560         if (!new_opp)
 561                 return ERR_PTR(-ENOMEM);
 562
 563         ret = of_property_read_u64(np, "opp-hz", &rate);
 564         if (ret < 0) {
 565                 /* "opp-hz" is optional for devices like power domains. */
 566                 if (!opp_table->is_genpd) {
 567                         dev_err(dev, "%s: opp-hz not found\n", __func__);
 568                         goto free_opp;
 569                 }
 570
 571                 rate_not_available = true;
 572         } else {
 573                 /*
 574                  * Rate is defined as an unsigned long in clk API, and so
 575                  * casting explicitly to its type. Must be fixed once rate is 64
 576                  * bit guaranteed in clk API.
 577                  */
 578                 new_opp->rate = (unsigned long)rate;
 579         }
 580
 581         of_property_read_u32(np, "opp-level", &new_opp->level);
 582
 583         /* Check if the OPP supports hardware's hierarchy of versions or not */
 584         if (!_opp_is_supported(dev, opp_table, np)) {
 585                 dev_dbg(dev, "OPP not supported by hardware: %llu\n", rate);
 586                 goto free_opp;
 587         }
 588
 589         new_opp->turbo = of_property_read_bool(np, "turbo-mode");
 590
 591         new_opp->np = np;
 592         new_opp->dynamic = false;
 593         new_opp->available = true;
 594
 595         ret = _of_opp_alloc_required_opps(opp_table, new_opp);
 596         if (ret)
 597                 goto free_opp;
 598
 599         if (!of_property_read_u32(np, "clock-latency-ns", &val))
 600                 new_opp->clock_latency_ns = val;
 601
 602         ret = opp_parse_supplies(new_opp, dev, opp_table);
 603         if (ret)
 604                 goto free_required_opps;
 605
 606         if (opp_table->is_genpd)
 607                 new_opp->pstate = pm_genpd_opp_to_performance_state(dev, new_opp);
 608
 609         ret = _opp_add(dev, new_opp, opp_table, rate_not_available);
 610         if (ret) {
 611                 /* Don't return error for duplicate OPPs */
 612                 if (ret == -EBUSY)
 613                         ret = 0;
 614                 goto free_required_opps;
 615         }
 616
 617         /* OPP to select on device suspend */
 618         if (of_property_read_bool(np, "opp-suspend")) {
 619                 if (opp_table->suspend_opp) {
 620                         dev_warn(dev, "%s: Multiple suspend OPPs found (%lu %lu)\n",
 621                                  __func__, opp_table->suspend_opp->rate,
 622                                  new_opp->rate);
 623                 } else {
 624                         new_opp->suspend = true;
 625                         opp_table->suspend_opp = new_opp;
 626                 }
 627         }
 628
 629         if (new_opp->clock_latency_ns > opp_table->clock_latency_ns_max)
 630                 opp_table->clock_latency_ns_max = new_opp->clock_latency_ns;
 631
 632         pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu\n",
 633                  __func__, new_opp->turbo, new_opp->rate,
 634                  new_opp->supplies[0].u_volt, new_opp->supplies[0].u_volt_min,
 635                  new_opp->supplies[0].u_volt_max, new_opp->clock_latency_ns);
 636
 637         /*
 638          * Notify the changes in the availability of the operable
 639          * frequency/voltage list.
 640          */
 641         blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ADD, new_opp);
 642         return new_opp;
 643
 644 free_required_opps:
 645         _of_opp_free_required_opps(opp_table, new_opp);
 646 free_opp:
 647         _opp_free(new_opp);
 648
 649         return ERR_PTR(ret);
 650 }
 651
 652 /* Initializes OPP tables based on new bindings */
 653 static int _of_add_opp_table_v2(struct device *dev, struct opp_table *opp_table)
 654 {
 655         struct device_node *np;
 656         int ret, count = 0, pstate_count = 0;
 657         struct dev_pm_opp *opp;
 658
 659         /* OPP table is already initialized for the device */
 660         if (opp_table->parsed_static_opps) {
 661                 kref_get(&opp_table->list_kref);
 662                 return 0;
 663         }
 664
 665         kref_init(&opp_table->list_kref);
 666
 667         /* We have opp-table node now, iterate over it and add OPPs */
 668         for_each_available_child_of_node(opp_table->np, np) {
 669                 opp = _opp_add_static_v2(opp_table, dev, np);
 670                 if (IS_ERR(opp)) {
 671                         ret = PTR_ERR(opp);
 672                         dev_err(dev, "%s: Failed to add OPP, %d\n", __func__,
 673                                 ret);
 674                         of_node_put(np);
 675                         goto put_list_kref;
 676                 } else if (opp) {
 677                         count++;
 678                 }
 679         }
 680
 681         /* There should be one of more OPP defined */
 682         if (WARN_ON(!count)) {
 683                 ret = -ENOENT;
 684                 goto put_list_kref;
 685         }
 686
 687         list_for_each_entry(opp, &opp_table->opp_list, node)
 688                 pstate_count += !!opp->pstate;
 689
 690         /* Either all or none of the nodes shall have performance state set */
 691         if (pstate_count && pstate_count != count) {
 692                 dev_err(dev, "Not all nodes have performance state set (%d: %d)\n",
 693                         count, pstate_count);
 694                 ret = -ENOENT;
 695                 goto put_list_kref;
 696         }
 697
 698         if (pstate_count)
 699                 opp_table->genpd_performance_state = true;
 700
 701         opp_table->parsed_static_opps = true;
 702
 703         return 0;
 704
 705 put_list_kref:
 706         _put_opp_list_kref(opp_table);
 707
 708         return ret;
 709 }
 710
 711 /* Initializes OPP tables based on old-deprecated bindings */
 712 static int _of_add_opp_table_v1(struct device *dev, struct opp_table *opp_table)
 713 {
 714         const struct property *prop;
 715         const __be32 *val;
 716         int nr, ret = 0;
 717
 718         prop = of_find_property(dev->of_node, "operating-points", NULL);
 719         if (!prop)
 720                 return -ENODEV;
 721         if (!prop->value)
 722                 return -ENODATA;
 723
 724         /*
 725          * Each OPP is a set of tuples consisting of frequency and
 726          * voltage like <freq-kHz vol-uV>.
 727          */
 728         nr = prop->length / sizeof(u32);
 729         if (nr % 2) {
 730                 dev_err(dev, "%s: Invalid OPP table\n", __func__);
 731                 return -EINVAL;
 732         }
 733
 734         kref_init(&opp_table->list_kref);
 735
 736         val = prop->value;
 737         while (nr) {
 738                 unsigned long freq = be32_to_cpup(val++) * 1000;
 739                 unsigned long volt = be32_to_cpup(val++);
 740
 741                 ret = _opp_add_v1(opp_table, dev, freq, volt, false);
 742                 if (ret) {
 743                         dev_err(dev, "%s: Failed to add OPP %ld (%d)\n",
 744                                 __func__, freq, ret);
 745                         _put_opp_list_kref(opp_table);
 746                         return ret;
 747                 }
 748                 nr -= 2;
 749         }
 750
 751         return ret;
 752 }
 753
 754 /**
 755  * dev_pm_opp_of_add_table() - Initialize opp table from device tree
 756  * @dev:        device pointer used to lookup OPP table.
 757  *
 758  * Register the initial OPP table with the OPP library for given device.
 759  *
 760  * Return:
 761  * 0            On success OR
 762  *              Duplicate OPPs (both freq and volt are same) and opp->available
 763  * -EEXIST      Freq are same and volt are different OR
 764  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 765  * -ENOMEM      Memory allocation failure
 766  * -ENODEV      when 'operating-points' property is not found or is invalid data
 767  *              in device node.
 768  * -ENODATA     when empty 'operating-points' property is found
 769  * -EINVAL      when invalid entries are found in opp-v2 table
 770  */
 771 int dev_pm_opp_of_add_table(struct device *dev)
 772 {
 773         struct opp_table *opp_table;
 774         int ret;
 775
 776         opp_table = dev_pm_opp_get_opp_table_indexed(dev, 0);
 777         if (!opp_table)
 778                 return -ENOMEM;
 779
 780         /*
 781          * OPPs have two version of bindings now. Also try the old (v1)
 782          * bindings for backward compatibility with older dtbs.
 783          */
 784         if (opp_table->np)
 785                 ret = _of_add_opp_table_v2(dev, opp_table);
 786         else
 787                 ret = _of_add_opp_table_v1(dev, opp_table);
 788
 789         if (ret)
 790                 dev_pm_opp_put_opp_table(opp_table);
 791
 792         return ret;
 793 }
 794 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table);
 795
 796 /**
 797  * dev_pm_opp_of_add_table_indexed() - Initialize indexed opp table from device tree
 798  * @dev:        device pointer used to lookup OPP table.
 799  * @index:      Index number.
 800  *
 801  * Register the initial OPP table with the OPP library for given device only
 802  * using the "operating-points-v2" property.
 803  *
 804  * Return:
 805  * 0            On success OR
 806  *              Duplicate OPPs (both freq and volt are same) and opp->available
 807  * -EEXIST      Freq are same and volt are different OR
 808  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 809  * -ENOMEM      Memory allocation failure
 810  * -ENODEV      when 'operating-points' property is not found or is invalid data
 811  *              in device node.
 812  * -ENODATA     when empty 'operating-points' property is found
 813  * -EINVAL      when invalid entries are found in opp-v2 table
 814  */
 815 int dev_pm_opp_of_add_table_indexed(struct device *dev, int index)
 816 {
 817         struct opp_table *opp_table;
 818         int ret, count;
 819
 820         if (index) {
 821                 /*
 822                  * If only one phandle is present, then the same OPP table
 823                  * applies for all index requests.
 824                  */
 825                 count = of_count_phandle_with_args(dev->of_node,
 826                                                    "operating-points-v2", NULL);
 827                 if (count == 1)
 828                         index = 0;
 829         }
 830
 831         opp_table = dev_pm_opp_get_opp_table_indexed(dev, index);
 832         if (!opp_table)
 833                 return -ENOMEM;
 834
 835         ret = _of_add_opp_table_v2(dev, opp_table);
 836         if (ret)
 837                 dev_pm_opp_put_opp_table(opp_table);
 838
 839         return ret;
 840 }
 841 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table_indexed);
 842
 843 /* CPU device specific helpers */
 844
 845 /**
 846  * dev_pm_opp_of_cpumask_remove_table() - Removes OPP table for @cpumask
 847  * @cpumask:    cpumask for which OPP table needs to be removed
 848  *
 849  * This removes the OPP tables for CPUs present in the @cpumask.
 850  * This should be used only to remove static entries created from DT.
 851  */
 852 void dev_pm_opp_of_cpumask_remove_table(const struct cpumask *cpumask)
 853 {
 854         _dev_pm_opp_cpumask_remove_table(cpumask, -1);
 855 }
 856 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_remove_table);
 857
 858 /**
 859  * dev_pm_opp_of_cpumask_add_table() - Adds OPP table for @cpumask
 860  * @cpumask:    cpumask for which OPP table needs to be added.
 861  *
 862  * This adds the OPP tables for CPUs present in the @cpumask.
 863  */
 864 int dev_pm_opp_of_cpumask_add_table(const struct cpumask *cpumask)
 865 {
 866         struct device *cpu_dev;
 867         int cpu, ret;
 868
 869         if (WARN_ON(cpumask_empty(cpumask)))
 870                 return -ENODEV;
 871
 872         for_each_cpu(cpu, cpumask) {
 873                 cpu_dev = get_cpu_device(cpu);
 874                 if (!cpu_dev) {
 875                         pr_err("%s: failed to get cpu%d device\n", __func__,
 876                                cpu);
 877                         ret = -ENODEV;
 878                         goto remove_table;
 879                 }
 880
 881                 ret = dev_pm_opp_of_add_table(cpu_dev);
 882                 if (ret) {
 883                         /*
 884                          * OPP may get registered dynamically, don't print error
 885                          * message here.
 886                          */
 887                         pr_debug("%s: couldn't find opp table for cpu:%d, %d\n",
 888                                  __func__, cpu, ret);
 889
 890                         goto remove_table;
 891                 }
 892         }
 893
 894         return 0;
 895
 896 remove_table:
 897         /* Free all other OPPs */
 898         _dev_pm_opp_cpumask_remove_table(cpumask, cpu);
 899
 900         return ret;
 901 }
 902 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_add_table);
 903
 904 /*
 905  * Works only for OPP v2 bindings.
 906  *
 907  * Returns -ENOENT if operating-points-v2 bindings aren't supported.
 908  */
 909 /**
 910  * dev_pm_opp_of_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with
 911  *                                    @cpu_dev using operating-points-v2
 912  *                                    bindings.
 913  *
 914  * @cpu_dev:    CPU device for which we do this operation
 915  * @cpumask:    cpumask to update with information of sharing CPUs
 916  *
 917  * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev.
 918  *
 919  * Returns -ENOENT if operating-points-v2 isn't present for @cpu_dev.
 920  */
 921 int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev,
 922                                    struct cpumask *cpumask)
 923 {
 924         struct device_node *np, *tmp_np, *cpu_np;
 925         int cpu, ret = 0;
 926
 927         /* Get OPP descriptor node */
 928         np = dev_pm_opp_of_get_opp_desc_node(cpu_dev);
 929         if (!np) {
 930                 dev_dbg(cpu_dev, "%s: Couldn't find opp node.\n", __func__);
 931                 return -ENOENT;
 932         }
 933
 934         cpumask_set_cpu(cpu_dev->id, cpumask);
 935
 936         /* OPPs are shared ? */
 937         if (!of_property_read_bool(np, "opp-shared"))
 938                 goto put_cpu_node;
 939
 940         for_each_possible_cpu(cpu) {
 941                 if (cpu == cpu_dev->id)
 942                         continue;
 943
 944                 cpu_np = of_cpu_device_node_get(cpu);
 945                 if (!cpu_np) {
 946                         dev_err(cpu_dev, "%s: failed to get cpu%d node\n",
 947                                 __func__, cpu);
 948                         ret = -ENOENT;
 949                         goto put_cpu_node;
 950                 }
 951
 952                 /* Get OPP descriptor node */
 953                 tmp_np = _opp_of_get_opp_desc_node(cpu_np, 0);
 954                 of_node_put(cpu_np);
 955                 if (!tmp_np) {
 956                         pr_err("%pOF: Couldn't find opp node\n", cpu_np);
 957                         ret = -ENOENT;
 958                         goto put_cpu_node;
 959                 }
 960
 961                 /* CPUs are sharing opp node */
 962                 if (np == tmp_np)
 963                         cpumask_set_cpu(cpu, cpumask);
 964
 965                 of_node_put(tmp_np);
 966         }
 967
 968 put_cpu_node:
 969         of_node_put(np);
 970         return ret;
 971 }
 972 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus);
 973
 974 /**
 975  * of_get_required_opp_performance_state() - Search for required OPP and return its performance state.
 976  * @np: Node that contains the "required-opps" property.
 977  * @index: Index of the phandle to parse.
 978  *
 979  * Returns the performance state of the OPP pointed out by the "required-opps"
 980  * property at @index in @np.
 981  *
 982  * Return: Zero or positive performance state on success, otherwise negative
 983  * value on errors.
 984  */
 985 int of_get_required_opp_performance_state(struct device_node *np, int index)
 986 {
 987         struct dev_pm_opp *opp;
 988         struct device_node *required_np;
 989         struct opp_table *opp_table;
 990         int pstate = -EINVAL;
 991
 992         required_np = of_parse_required_opp(np, index);
 993         if (!required_np)
 994                 return -EINVAL;
 995
 996         opp_table = _find_table_of_opp_np(required_np);
 997         if (IS_ERR(opp_table)) {
 998                 pr_err("%s: Failed to find required OPP table %pOF: %ld\n",
 999                        __func__, np, PTR_ERR(opp_table));
1000                 goto put_required_np;
1001         }
1002
1003         opp = _find_opp_of_np(opp_table, required_np);
1004         if (opp) {
1005                 pstate = opp->pstate;
1006                 dev_pm_opp_put(opp);
1007         }
1008
1009         dev_pm_opp_put_opp_table(opp_table);
1010
1011 put_required_np:
1012         of_node_put(required_np);
1013
1014         return pstate;
1015 }
1016 EXPORT_SYMBOL_GPL(of_get_required_opp_performance_state);
1017
1018 /**
1019  * dev_pm_opp_get_of_node() - Gets the DT node corresponding to an opp
1020  * @opp:        opp for which DT node has to be returned for
1021  *
1022  * Return: DT node corresponding to the opp, else 0 on success.
1023  *
1024  * The caller needs to put the node with of_node_put() after using it.
1025  */
1026 struct device_node *dev_pm_opp_get_of_node(struct dev_pm_opp *opp)
1027 {
1028         if (IS_ERR_OR_NULL(opp)) {
1029                 pr_err("%s: Invalid parameters\n", __func__);
1030                 return NULL;
1031         }
1032
1033         return of_node_get(opp->np);
1034 }
1035 EXPORT_SYMBOL_GPL(dev_pm_opp_get_of_node);
1036
1037 /*
1038  * Callback function provided to the Energy Model framework upon registration.
1039  * This computes the power estimated by @CPU at @kHz if it is the frequency
1040  * of an existing OPP, or at the frequency of the first OPP above @kHz otherwise
1041  * (see dev_pm_opp_find_freq_ceil()). This function updates @kHz to the ceiled
1042  * frequency and @mW to the associated power. The power is estimated as
1043  * P = C * V^2 * f with C being the CPU's capacitance and V and f respectively
1044  * the voltage and frequency of the OPP.
1045  *
1046  * Returns -ENODEV if the CPU device cannot be found, -EINVAL if the power
1047  * calculation failed because of missing parameters, 0 otherwise.
1048  */
1049 static int __maybe_unused _get_cpu_power(unsigned long *mW, unsigned long *kHz,
1050                                          int cpu)
1051 {
1052         struct device *cpu_dev;
1053         struct dev_pm_opp *opp;
1054         struct device_node *np;
1055         unsigned long mV, Hz;
1056         u32 cap;
1057         u64 tmp;
1058         int ret;
1059
1060         cpu_dev = get_cpu_device(cpu);
1061         if (!cpu_dev)
1062                 return -ENODEV;
1063
1064         np = of_node_get(cpu_dev->of_node);
1065         if (!np)
1066                 return -EINVAL;
1067
1068         ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1069         of_node_put(np);
1070         if (ret)
1071                 return -EINVAL;
1072
1073         Hz = *kHz * 1000;
1074         opp = dev_pm_opp_find_freq_ceil(cpu_dev, &Hz);
1075         if (IS_ERR(opp))
1076                 return -EINVAL;
1077
1078         mV = dev_pm_opp_get_voltage(opp) / 1000;
1079         dev_pm_opp_put(opp);
1080         if (!mV)
1081                 return -EINVAL;
1082
1083         tmp = (u64)cap * mV * mV * (Hz / 1000000);
1084         do_div(tmp, 1000000000);
1085
1086         *mW = (unsigned long)tmp;
1087         *kHz = Hz / 1000;
1088
1089         return 0;
1090 }
1091
1092 /**
1093  * dev_pm_opp_of_register_em() - Attempt to register an Energy Model
1094  * @cpus        : CPUs for which an Energy Model has to be registered
1095  *
1096  * This checks whether the "dynamic-power-coefficient" devicetree property has
1097  * been specified, and tries to register an Energy Model with it if it has.
1098  */
1099 void dev_pm_opp_of_register_em(struct cpumask *cpus)
1100 {
1101         struct em_data_callback em_cb = EM_DATA_CB(_get_cpu_power);
1102         int ret, nr_opp, cpu = cpumask_first(cpus);
1103         struct device *cpu_dev;
1104         struct device_node *np;
1105         u32 cap;
1106
1107         cpu_dev = get_cpu_device(cpu);
1108         if (!cpu_dev)
1109                 return;
1110
1111         nr_opp = dev_pm_opp_get_opp_count(cpu_dev);
1112         if (nr_opp <= 0)
1113                 return;
1114
1115         np = of_node_get(cpu_dev->of_node);
1116         if (!np)
1117                 return;
1118
1119         /*
1120          * Register an EM only if the 'dynamic-power-coefficient' property is
1121          * set in devicetree. It is assumed the voltage values are known if that
1122          * property is set since it is useless otherwise. If voltages are not
1123          * known, just let the EM registration fail with an error to alert the
1124          * user about the inconsistent configuration.
1125          */
1126         ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1127         of_node_put(np);
1128         if (ret || !cap)
1129                 return;
1130
1131         em_register_perf_domain(cpus, nr_opp, &em_cb);
1132 }
1133 EXPORT_SYMBOL_GPL(dev_pm_opp_of_register_em);