drivers/opp/of.c

   1 /*
   2  * Generic OPP OF helpers
   3  *
   4  * Copyright (C) 2009-2010 Texas Instruments Incorporated.
   5  *      Nishanth Menon
   6  *      Romit Dasgupta
   7  *      Kevin Hilman
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  */
  13
  14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  15
  16 #include <linux/cpu.h>
  17 #include <linux/errno.h>
  18 #include <linux/device.h>
  19 #include <linux/of_device.h>
  20 #include <linux/pm_domain.h>
  21 #include <linux/slab.h>
  22 #include <linux/export.h>
  23
  24 #include "opp.h"
  25
  26 /*
  27  * Returns opp descriptor node for a device node, caller must
  28  * do of_node_put().
  29  */
  30 static struct device_node *_opp_of_get_opp_desc_node(struct device_node *np,
  31                                                      int index)
  32 {
  33         /* "operating-points-v2" can be an array for power domain providers */
  34         return of_parse_phandle(np, "operating-points-v2", index);
  35 }
  36
  37 /* Returns opp descriptor node for a device, caller must do of_node_put() */
  38 struct device_node *dev_pm_opp_of_get_opp_desc_node(struct device *dev)
  39 {
  40         return _opp_of_get_opp_desc_node(dev->of_node, 0);
  41 }
  42 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_opp_desc_node);
  43
  44 struct opp_table *_managed_opp(struct device *dev, int index)
  45 {
  46         struct opp_table *opp_table, *managed_table = NULL;
  47         struct device_node *np;
  48
  49         np = _opp_of_get_opp_desc_node(dev->of_node, index);
  50         if (!np)
  51                 return NULL;
  52
  53         list_for_each_entry(opp_table, &opp_tables, node) {
  54                 if (opp_table->np == np) {
  55                         /*
  56                          * Multiple devices can point to the same OPP table and
  57                          * so will have same node-pointer, np.
  58                          *
  59                          * But the OPPs will be considered as shared only if the
  60                          * OPP table contains a "opp-shared" property.
  61                          */
  62                         if (opp_table->shared_opp == OPP_TABLE_ACCESS_SHARED) {
  63                                 _get_opp_table_kref(opp_table);
  64                                 managed_table = opp_table;
  65                         }
  66
  67                         break;
  68                 }
  69         }
  70
  71         of_node_put(np);
  72
  73         return managed_table;
  74 }
  75
  76 /* The caller must call dev_pm_opp_put() after the OPP is used */
  77 static struct dev_pm_opp *_find_opp_of_np(struct opp_table *opp_table,
  78                                           struct device_node *opp_np)
  79 {
  80         struct dev_pm_opp *opp;
  81
  82         lockdep_assert_held(&opp_table_lock);
  83
  84         mutex_lock(&opp_table->lock);
  85
  86         list_for_each_entry(opp, &opp_table->opp_list, node) {
  87                 if (opp->np == opp_np) {
  88                         dev_pm_opp_get(opp);
  89                         mutex_unlock(&opp_table->lock);
  90                         return opp;
  91                 }
  92         }
  93
  94         mutex_unlock(&opp_table->lock);
  95
  96         return NULL;
  97 }
  98
  99 static struct device_node *of_parse_required_opp(struct device_node *np,
 100                                                  int index)
 101 {
 102         struct device_node *required_np;
 103
 104         required_np = of_parse_phandle(np, "required-opps", index);
 105         if (unlikely(!required_np)) {
 106                 pr_err("%s: Unable to parse required-opps: %pOF, index: %d\n",
 107                        __func__, np, index);
 108         }
 109
 110         return required_np;
 111 }
 112
 113 /* The caller must call dev_pm_opp_put_opp_table() after the table is used */
 114 static struct opp_table *_find_table_of_opp_np(struct device_node *opp_np)
 115 {
 116         struct opp_table *opp_table;
 117         struct dev_pm_opp *opp;
 118
 119         lockdep_assert_held(&opp_table_lock);
 120
 121         list_for_each_entry(opp_table, &opp_tables, node) {
 122                 opp = _find_opp_of_np(opp_table, opp_np);
 123                 if (opp) {
 124                         dev_pm_opp_put(opp);
 125                         _get_opp_table_kref(opp_table);
 126                         return opp_table;
 127                 }
 128         }
 129
 130         return ERR_PTR(-ENODEV);
 131 }
 132
 133 /* Free resources previously acquired by _opp_table_alloc_required_tables() */
 134 static void _opp_table_free_required_tables(struct opp_table *opp_table)
 135 {
 136         struct opp_table **required_opp_tables = opp_table->required_opp_tables;
 137         struct device **genpd_virt_devs = opp_table->genpd_virt_devs;
 138         int i;
 139
 140         if (!required_opp_tables)
 141                 return;
 142
 143         for (i = 0; i < opp_table->required_opp_count; i++) {
 144                 if (IS_ERR_OR_NULL(required_opp_tables[i]))
 145                         break;
 146
 147                 dev_pm_opp_put_opp_table(required_opp_tables[i]);
 148         }
 149
 150         kfree(required_opp_tables);
 151         kfree(genpd_virt_devs);
 152
 153         opp_table->required_opp_count = 0;
 154         opp_table->genpd_virt_devs = NULL;
 155         opp_table->required_opp_tables = NULL;
 156 }
 157
 158 /*
 159  * Populate all devices and opp tables which are part of "required-opps" list.
 160  * Checking only the first OPP node should be enough.
 161  */
 162 static void _opp_table_alloc_required_tables(struct opp_table *opp_table,
 163                                              struct device *dev,
 164                                              struct device_node *opp_np)
 165 {
 166         struct opp_table **required_opp_tables;
 167         struct device **genpd_virt_devs = NULL;
 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         if (count > 1) {
 183                 genpd_virt_devs = kcalloc(count, sizeof(*genpd_virt_devs),
 184                                         GFP_KERNEL);
 185                 if (!genpd_virt_devs)
 186                         goto put_np;
 187         }
 188
 189         required_opp_tables = kcalloc(count, sizeof(*required_opp_tables),
 190                                       GFP_KERNEL);
 191         if (!required_opp_tables) {
 192                 kfree(genpd_virt_devs);
 193                 goto put_np;
 194         }
 195
 196         opp_table->genpd_virt_devs = genpd_virt_devs;
 197         opp_table->required_opp_tables = required_opp_tables;
 198         opp_table->required_opp_count = count;
 199
 200         for (i = 0; i < count; i++) {
 201                 required_np = of_parse_required_opp(np, i);
 202                 if (!required_np)
 203                         goto free_required_tables;
 204
 205                 required_opp_tables[i] = _find_table_of_opp_np(required_np);
 206                 of_node_put(required_np);
 207
 208                 if (IS_ERR(required_opp_tables[i]))
 209                         goto free_required_tables;
 210
 211                 /*
 212                  * We only support genpd's OPPs in the "required-opps" for now,
 213                  * as we don't know how much about other cases. Error out if the
 214                  * required OPP doesn't belong to a genpd.
 215                  */
 216                 if (!required_opp_tables[i]->is_genpd) {
 217                         dev_err(dev, "required-opp doesn't belong to genpd: %pOF\n",
 218                                 required_np);
 219                         goto free_required_tables;
 220                 }
 221         }
 222
 223         goto put_np;
 224
 225 free_required_tables:
 226         _opp_table_free_required_tables(opp_table);
 227 put_np:
 228         of_node_put(np);
 229 }
 230
 231 void _of_init_opp_table(struct opp_table *opp_table, struct device *dev,
 232                         int index)
 233 {
 234         struct device_node *np, *opp_np;
 235         u32 val;
 236
 237         /*
 238          * Only required for backward compatibility with v1 bindings, but isn't
 239          * harmful for other cases. And so we do it unconditionally.
 240          */
 241         np = of_node_get(dev->of_node);
 242         if (!np)
 243                 return;
 244
 245         if (!of_property_read_u32(np, "clock-latency", &val))
 246                 opp_table->clock_latency_ns_max = val;
 247         of_property_read_u32(np, "voltage-tolerance",
 248                              &opp_table->voltage_tolerance_v1);
 249
 250         if (of_find_property(np, "#power-domain-cells", NULL))
 251                 opp_table->is_genpd = true;
 252
 253         /* Get OPP table node */
 254         opp_np = _opp_of_get_opp_desc_node(np, index);
 255         of_node_put(np);
 256
 257         if (!opp_np)
 258                 return;
 259
 260         if (of_property_read_bool(opp_np, "opp-shared"))
 261                 opp_table->shared_opp = OPP_TABLE_ACCESS_SHARED;
 262         else
 263                 opp_table->shared_opp = OPP_TABLE_ACCESS_EXCLUSIVE;
 264
 265         opp_table->np = opp_np;
 266
 267         _opp_table_alloc_required_tables(opp_table, dev, opp_np);
 268         of_node_put(opp_np);
 269 }
 270
 271 void _of_clear_opp_table(struct opp_table *opp_table)
 272 {
 273         _opp_table_free_required_tables(opp_table);
 274 }
 275
 276 /*
 277  * Release all resources previously acquired with a call to
 278  * _of_opp_alloc_required_opps().
 279  */
 280 void _of_opp_free_required_opps(struct opp_table *opp_table,
 281                                 struct dev_pm_opp *opp)
 282 {
 283         struct dev_pm_opp **required_opps = opp->required_opps;
 284         int i;
 285
 286         if (!required_opps)
 287                 return;
 288
 289         for (i = 0; i < opp_table->required_opp_count; i++) {
 290                 if (!required_opps[i])
 291                         break;
 292
 293                 /* Put the reference back */
 294                 dev_pm_opp_put(required_opps[i]);
 295         }
 296
 297         kfree(required_opps);
 298         opp->required_opps = NULL;
 299 }
 300
 301 /* Populate all required OPPs which are part of "required-opps" list */
 302 static int _of_opp_alloc_required_opps(struct opp_table *opp_table,
 303                                        struct dev_pm_opp *opp)
 304 {
 305         struct dev_pm_opp **required_opps;
 306         struct opp_table *required_table;
 307         struct device_node *np;
 308         int i, ret, count = opp_table->required_opp_count;
 309
 310         if (!count)
 311                 return 0;
 312
 313         required_opps = kcalloc(count, sizeof(*required_opps), GFP_KERNEL);
 314         if (!required_opps)
 315                 return -ENOMEM;
 316
 317         opp->required_opps = required_opps;
 318
 319         for (i = 0; i < count; i++) {
 320                 required_table = opp_table->required_opp_tables[i];
 321
 322                 np = of_parse_required_opp(opp->np, i);
 323                 if (unlikely(!np)) {
 324                         ret = -ENODEV;
 325                         goto free_required_opps;
 326                 }
 327
 328                 required_opps[i] = _find_opp_of_np(required_table, np);
 329                 of_node_put(np);
 330
 331                 if (!required_opps[i]) {
 332                         pr_err("%s: Unable to find required OPP node: %pOF (%d)\n",
 333                                __func__, opp->np, i);
 334                         ret = -ENODEV;
 335                         goto free_required_opps;
 336                 }
 337         }
 338
 339         return 0;
 340
 341 free_required_opps:
 342         _of_opp_free_required_opps(opp_table, opp);
 343
 344         return ret;
 345 }
 346
 347 static bool _opp_is_supported(struct device *dev, struct opp_table *opp_table,
 348                               struct device_node *np)
 349 {
 350         unsigned int count = opp_table->supported_hw_count;
 351         u32 version;
 352         int ret;
 353
 354         if (!opp_table->supported_hw) {
 355                 /*
 356                  * In the case that no supported_hw has been set by the
 357                  * platform but there is an opp-supported-hw value set for
 358                  * an OPP then the OPP should not be enabled as there is
 359                  * no way to see if the hardware supports it.
 360                  */
 361                 if (of_find_property(np, "opp-supported-hw", NULL))
 362                         return false;
 363                 else
 364                         return true;
 365         }
 366
 367         while (count--) {
 368                 ret = of_property_read_u32_index(np, "opp-supported-hw", count,
 369                                                  &version);
 370                 if (ret) {
 371                         dev_warn(dev, "%s: failed to read opp-supported-hw property at index %d: %d\n",
 372                                  __func__, count, ret);
 373                         return false;
 374                 }
 375
 376                 /* Both of these are bitwise masks of the versions */
 377                 if (!(version & opp_table->supported_hw[count]))
 378                         return false;
 379         }
 380
 381         return true;
 382 }
 383
 384 static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,
 385                               struct opp_table *opp_table)
 386 {
 387         u32 *microvolt, *microamp = NULL;
 388         int supplies, vcount, icount, ret, i, j;
 389         struct property *prop = NULL;
 390         char name[NAME_MAX];
 391
 392         supplies = opp_table->regulator_count ? opp_table->regulator_count : 1;
 393
 394         /* Search for "opp-microvolt-<name>" */
 395         if (opp_table->prop_name) {
 396                 snprintf(name, sizeof(name), "opp-microvolt-%s",
 397                          opp_table->prop_name);
 398                 prop = of_find_property(opp->np, name, NULL);
 399         }
 400
 401         if (!prop) {
 402                 /* Search for "opp-microvolt" */
 403                 sprintf(name, "opp-microvolt");
 404                 prop = of_find_property(opp->np, name, NULL);
 405
 406                 /* Missing property isn't a problem, but an invalid entry is */
 407                 if (!prop) {
 408                         if (!opp_table->regulator_count)
 409                                 return 0;
 410
 411                         dev_err(dev, "%s: opp-microvolt missing although OPP managing regulators\n",
 412                                 __func__);
 413                         return -EINVAL;
 414                 }
 415         }
 416
 417         vcount = of_property_count_u32_elems(opp->np, name);
 418         if (vcount < 0) {
 419                 dev_err(dev, "%s: Invalid %s property (%d)\n",
 420                         __func__, name, vcount);
 421                 return vcount;
 422         }
 423
 424         /* There can be one or three elements per supply */
 425         if (vcount != supplies && vcount != supplies * 3) {
 426                 dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
 427                         __func__, name, vcount, supplies);
 428                 return -EINVAL;
 429         }
 430
 431         microvolt = kmalloc_array(vcount, sizeof(*microvolt), GFP_KERNEL);
 432         if (!microvolt)
 433                 return -ENOMEM;
 434
 435         ret = of_property_read_u32_array(opp->np, name, microvolt, vcount);
 436         if (ret) {
 437                 dev_err(dev, "%s: error parsing %s: %d\n", __func__, name, ret);
 438                 ret = -EINVAL;
 439                 goto free_microvolt;
 440         }
 441
 442         /* Search for "opp-microamp-<name>" */
 443         prop = NULL;
 444         if (opp_table->prop_name) {
 445                 snprintf(name, sizeof(name), "opp-microamp-%s",
 446                          opp_table->prop_name);
 447                 prop = of_find_property(opp->np, name, NULL);
 448         }
 449
 450         if (!prop) {
 451                 /* Search for "opp-microamp" */
 452                 sprintf(name, "opp-microamp");
 453                 prop = of_find_property(opp->np, name, NULL);
 454         }
 455
 456         if (prop) {
 457                 icount = of_property_count_u32_elems(opp->np, name);
 458                 if (icount < 0) {
 459                         dev_err(dev, "%s: Invalid %s property (%d)\n", __func__,
 460                                 name, icount);
 461                         ret = icount;
 462                         goto free_microvolt;
 463                 }
 464
 465                 if (icount != supplies) {
 466                         dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
 467                                 __func__, name, icount, supplies);
 468                         ret = -EINVAL;
 469                         goto free_microvolt;
 470                 }
 471
 472                 microamp = kmalloc_array(icount, sizeof(*microamp), GFP_KERNEL);
 473                 if (!microamp) {
 474                         ret = -EINVAL;
 475                         goto free_microvolt;
 476                 }
 477
 478                 ret = of_property_read_u32_array(opp->np, name, microamp,
 479                                                  icount);
 480                 if (ret) {
 481                         dev_err(dev, "%s: error parsing %s: %d\n", __func__,
 482                                 name, ret);
 483                         ret = -EINVAL;
 484                         goto free_microamp;
 485                 }
 486         }
 487
 488         for (i = 0, j = 0; i < supplies; i++) {
 489                 opp->supplies[i].u_volt = microvolt[j++];
 490
 491                 if (vcount == supplies) {
 492                         opp->supplies[i].u_volt_min = opp->supplies[i].u_volt;
 493                         opp->supplies[i].u_volt_max = opp->supplies[i].u_volt;
 494                 } else {
 495                         opp->supplies[i].u_volt_min = microvolt[j++];
 496                         opp->supplies[i].u_volt_max = microvolt[j++];
 497                 }
 498
 499                 if (microamp)
 500                         opp->supplies[i].u_amp = microamp[i];
 501         }
 502
 503 free_microamp:
 504         kfree(microamp);
 505 free_microvolt:
 506         kfree(microvolt);
 507
 508         return ret;
 509 }
 510
 511 /**
 512  * dev_pm_opp_of_remove_table() - Free OPP table entries created from static DT
 513  *                                entries
 514  * @dev:        device pointer used to lookup OPP table.
 515  *
 516  * Free OPPs created using static entries present in DT.
 517  */
 518 void dev_pm_opp_of_remove_table(struct device *dev)
 519 {
 520         _dev_pm_opp_find_and_remove_table(dev);
 521 }
 522 EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table);
 523
 524 /**
 525  * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings)
 526  * @opp_table:  OPP table
 527  * @dev:        device for which we do this operation
 528  * @np:         device node
 529  *
 530  * This function adds an opp definition to the opp table and returns status. The
 531  * opp can be controlled using dev_pm_opp_enable/disable functions and may be
 532  * removed by dev_pm_opp_remove.
 533  *
 534  * Return:
 535  * Valid OPP pointer:
 536  *              On success
 537  * NULL:
 538  *              Duplicate OPPs (both freq and volt are same) and opp->available
 539  *              OR if the OPP is not supported by hardware.
 540  * ERR_PTR(-EEXIST):
 541  *              Freq are same and volt are different OR
 542  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 543  * ERR_PTR(-ENOMEM):
 544  *              Memory allocation failure
 545  * ERR_PTR(-EINVAL):
 546  *              Failed parsing the OPP node
 547  */
 548 static struct dev_pm_opp *_opp_add_static_v2(struct opp_table *opp_table,
 549                 struct device *dev, struct device_node *np)
 550 {
 551         struct dev_pm_opp *new_opp;
 552         u64 rate = 0;
 553         u32 val;
 554         int ret;
 555         bool rate_not_available = false;
 556
 557         new_opp = _opp_allocate(opp_table);
 558         if (!new_opp)
 559                 return ERR_PTR(-ENOMEM);
 560
 561         ret = of_property_read_u64(np, "opp-hz", &rate);
 562         if (ret < 0) {
 563                 /* "opp-hz" is optional for devices like power domains. */
 564                 if (!opp_table->is_genpd) {
 565                         dev_err(dev, "%s: opp-hz not found\n", __func__);
 566                         goto free_opp;
 567                 }
 568
 569                 rate_not_available = true;
 570         } else {
 571                 /*
 572                  * Rate is defined as an unsigned long in clk API, and so
 573                  * casting explicitly to its type. Must be fixed once rate is 64
 574                  * bit guaranteed in clk API.
 575                  */
 576                 new_opp->rate = (unsigned long)rate;
 577         }
 578
 579         /* Check if the OPP supports hardware's hierarchy of versions or not */
 580         if (!_opp_is_supported(dev, opp_table, np)) {
 581                 dev_dbg(dev, "OPP not supported by hardware: %llu\n", rate);
 582                 goto free_opp;
 583         }
 584
 585         new_opp->turbo = of_property_read_bool(np, "turbo-mode");
 586
 587         new_opp->np = np;
 588         new_opp->dynamic = false;
 589         new_opp->available = true;
 590
 591         ret = _of_opp_alloc_required_opps(opp_table, new_opp);
 592         if (ret)
 593                 goto free_opp;
 594
 595         if (!of_property_read_u32(np, "clock-latency-ns", &val))
 596                 new_opp->clock_latency_ns = val;
 597
 598         ret = opp_parse_supplies(new_opp, dev, opp_table);
 599         if (ret)
 600                 goto free_required_opps;
 601
 602         if (opp_table->is_genpd)
 603                 new_opp->pstate = pm_genpd_opp_to_performance_state(dev, new_opp);
 604
 605         ret = _opp_add(dev, new_opp, opp_table, rate_not_available);
 606         if (ret) {
 607                 /* Don't return error for duplicate OPPs */
 608                 if (ret == -EBUSY)
 609                         ret = 0;
 610                 goto free_required_opps;
 611         }
 612
 613         /* OPP to select on device suspend */
 614         if (of_property_read_bool(np, "opp-suspend")) {
 615                 if (opp_table->suspend_opp) {
 616                         dev_warn(dev, "%s: Multiple suspend OPPs found (%lu %lu)\n",
 617                                  __func__, opp_table->suspend_opp->rate,
 618                                  new_opp->rate);
 619                 } else {
 620                         new_opp->suspend = true;
 621                         opp_table->suspend_opp = new_opp;
 622                 }
 623         }
 624
 625         if (new_opp->clock_latency_ns > opp_table->clock_latency_ns_max)
 626                 opp_table->clock_latency_ns_max = new_opp->clock_latency_ns;
 627
 628         pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu\n",
 629                  __func__, new_opp->turbo, new_opp->rate,
 630                  new_opp->supplies[0].u_volt, new_opp->supplies[0].u_volt_min,
 631                  new_opp->supplies[0].u_volt_max, new_opp->clock_latency_ns);
 632
 633         /*
 634          * Notify the changes in the availability of the operable
 635          * frequency/voltage list.
 636          */
 637         blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ADD, new_opp);
 638         return new_opp;
 639
 640 free_required_opps:
 641         _of_opp_free_required_opps(opp_table, new_opp);
 642 free_opp:
 643         _opp_free(new_opp);
 644
 645         return ERR_PTR(ret);
 646 }
 647
 648 /* Initializes OPP tables based on new bindings */
 649 static int _of_add_opp_table_v2(struct device *dev, struct opp_table *opp_table)
 650 {
 651         struct device_node *np;
 652         int ret, count = 0, pstate_count = 0;
 653         struct dev_pm_opp *opp;
 654
 655         /* OPP table is already initialized for the device */
 656         if (opp_table->parsed_static_opps) {
 657                 kref_get(&opp_table->list_kref);
 658                 return 0;
 659         }
 660
 661         kref_init(&opp_table->list_kref);
 662
 663         /* We have opp-table node now, iterate over it and add OPPs */
 664         for_each_available_child_of_node(opp_table->np, np) {
 665                 opp = _opp_add_static_v2(opp_table, dev, np);
 666                 if (IS_ERR(opp)) {
 667                         ret = PTR_ERR(opp);
 668                         dev_err(dev, "%s: Failed to add OPP, %d\n", __func__,
 669                                 ret);
 670                         of_node_put(np);
 671                         goto put_list_kref;
 672                 } else if (opp) {
 673                         count++;
 674                 }
 675         }
 676
 677         /* There should be one of more OPP defined */
 678         if (WARN_ON(!count)) {
 679                 ret = -ENOENT;
 680                 goto put_list_kref;
 681         }
 682
 683         list_for_each_entry(opp, &opp_table->opp_list, node)
 684                 pstate_count += !!opp->pstate;
 685
 686         /* Either all or none of the nodes shall have performance state set */
 687         if (pstate_count && pstate_count != count) {
 688                 dev_err(dev, "Not all nodes have performance state set (%d: %d)\n",
 689                         count, pstate_count);
 690                 ret = -ENOENT;
 691                 goto put_list_kref;
 692         }
 693
 694         if (pstate_count)
 695                 opp_table->genpd_performance_state = true;
 696
 697         opp_table->parsed_static_opps = true;
 698
 699         return 0;
 700
 701 put_list_kref:
 702         _put_opp_list_kref(opp_table);
 703
 704         return ret;
 705 }
 706
 707 /* Initializes OPP tables based on old-deprecated bindings */
 708 static int _of_add_opp_table_v1(struct device *dev, struct opp_table *opp_table)
 709 {
 710         const struct property *prop;
 711         const __be32 *val;
 712         int nr, ret = 0;
 713
 714         prop = of_find_property(dev->of_node, "operating-points", NULL);
 715         if (!prop)
 716                 return -ENODEV;
 717         if (!prop->value)
 718                 return -ENODATA;
 719
 720         /*
 721          * Each OPP is a set of tuples consisting of frequency and
 722          * voltage like <freq-kHz vol-uV>.
 723          */
 724         nr = prop->length / sizeof(u32);
 725         if (nr % 2) {
 726                 dev_err(dev, "%s: Invalid OPP table\n", __func__);
 727                 return -EINVAL;
 728         }
 729
 730         kref_init(&opp_table->list_kref);
 731
 732         val = prop->value;
 733         while (nr) {
 734                 unsigned long freq = be32_to_cpup(val++) * 1000;
 735                 unsigned long volt = be32_to_cpup(val++);
 736
 737                 ret = _opp_add_v1(opp_table, dev, freq, volt, false);
 738                 if (ret) {
 739                         dev_err(dev, "%s: Failed to add OPP %ld (%d)\n",
 740                                 __func__, freq, ret);
 741                         _put_opp_list_kref(opp_table);
 742                         return ret;
 743                 }
 744                 nr -= 2;
 745         }
 746
 747         return ret;
 748 }
 749
 750 /**
 751  * dev_pm_opp_of_add_table() - Initialize opp table from device tree
 752  * @dev:        device pointer used to lookup OPP table.
 753  *
 754  * Register the initial OPP table with the OPP library for given device.
 755  *
 756  * Return:
 757  * 0            On success OR
 758  *              Duplicate OPPs (both freq and volt are same) and opp->available
 759  * -EEXIST      Freq are same and volt are different OR
 760  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 761  * -ENOMEM      Memory allocation failure
 762  * -ENODEV      when 'operating-points' property is not found or is invalid data
 763  *              in device node.
 764  * -ENODATA     when empty 'operating-points' property is found
 765  * -EINVAL      when invalid entries are found in opp-v2 table
 766  */
 767 int dev_pm_opp_of_add_table(struct device *dev)
 768 {
 769         struct opp_table *opp_table;
 770         int ret;
 771
 772         opp_table = dev_pm_opp_get_opp_table_indexed(dev, 0);
 773         if (!opp_table)
 774                 return -ENOMEM;
 775
 776         /*
 777          * OPPs have two version of bindings now. Also try the old (v1)
 778          * bindings for backward compatibility with older dtbs.
 779          */
 780         if (opp_table->np)
 781                 ret = _of_add_opp_table_v2(dev, opp_table);
 782         else
 783                 ret = _of_add_opp_table_v1(dev, opp_table);
 784
 785         if (ret)
 786                 dev_pm_opp_put_opp_table(opp_table);
 787
 788         return ret;
 789 }
 790 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table);
 791
 792 /**
 793  * dev_pm_opp_of_add_table_indexed() - Initialize indexed opp table from device tree
 794  * @dev:        device pointer used to lookup OPP table.
 795  * @index:      Index number.
 796  *
 797  * Register the initial OPP table with the OPP library for given device only
 798  * using the "operating-points-v2" property.
 799  *
 800  * Return:
 801  * 0            On success OR
 802  *              Duplicate OPPs (both freq and volt are same) and opp->available
 803  * -EEXIST      Freq are same and volt are different OR
 804  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 805  * -ENOMEM      Memory allocation failure
 806  * -ENODEV      when 'operating-points' property is not found or is invalid data
 807  *              in device node.
 808  * -ENODATA     when empty 'operating-points' property is found
 809  * -EINVAL      when invalid entries are found in opp-v2 table
 810  */
 811 int dev_pm_opp_of_add_table_indexed(struct device *dev, int index)
 812 {
 813         struct opp_table *opp_table;
 814         int ret, count;
 815
 816         if (index) {
 817                 /*
 818                  * If only one phandle is present, then the same OPP table
 819                  * applies for all index requests.
 820                  */
 821                 count = of_count_phandle_with_args(dev->of_node,
 822                                                    "operating-points-v2", NULL);
 823                 if (count != 1)
 824                         return -ENODEV;
 825
 826                 index = 0;
 827         }
 828
 829         opp_table = dev_pm_opp_get_opp_table_indexed(dev, index);
 830         if (!opp_table)
 831                 return -ENOMEM;
 832
 833         ret = _of_add_opp_table_v2(dev, opp_table);
 834         if (ret)
 835                 dev_pm_opp_put_opp_table(opp_table);
 836
 837         return ret;
 838 }
 839 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table_indexed);
 840
 841 /* CPU device specific helpers */
 842
 843 /**
 844  * dev_pm_opp_of_cpumask_remove_table() - Removes OPP table for @cpumask
 845  * @cpumask:    cpumask for which OPP table needs to be removed
 846  *
 847  * This removes the OPP tables for CPUs present in the @cpumask.
 848  * This should be used only to remove static entries created from DT.
 849  */
 850 void dev_pm_opp_of_cpumask_remove_table(const struct cpumask *cpumask)
 851 {
 852         _dev_pm_opp_cpumask_remove_table(cpumask, -1);
 853 }
 854 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_remove_table);
 855
 856 /**
 857  * dev_pm_opp_of_cpumask_add_table() - Adds OPP table for @cpumask
 858  * @cpumask:    cpumask for which OPP table needs to be added.
 859  *
 860  * This adds the OPP tables for CPUs present in the @cpumask.
 861  */
 862 int dev_pm_opp_of_cpumask_add_table(const struct cpumask *cpumask)
 863 {
 864         struct device *cpu_dev;
 865         int cpu, ret;
 866
 867         if (WARN_ON(cpumask_empty(cpumask)))
 868                 return -ENODEV;
 869
 870         for_each_cpu(cpu, cpumask) {
 871                 cpu_dev = get_cpu_device(cpu);
 872                 if (!cpu_dev) {
 873                         pr_err("%s: failed to get cpu%d device\n", __func__,
 874                                cpu);
 875                         ret = -ENODEV;
 876                         goto remove_table;
 877                 }
 878
 879                 ret = dev_pm_opp_of_add_table(cpu_dev);
 880                 if (ret) {
 881                         /*
 882                          * OPP may get registered dynamically, don't print error
 883                          * message here.
 884                          */
 885                         pr_debug("%s: couldn't find opp table for cpu:%d, %d\n",
 886                                  __func__, cpu, ret);
 887
 888                         goto remove_table;
 889                 }
 890         }
 891
 892         return 0;
 893
 894 remove_table:
 895         /* Free all other OPPs */
 896         _dev_pm_opp_cpumask_remove_table(cpumask, cpu);
 897
 898         return ret;
 899 }
 900 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_add_table);
 901
 902 /*
 903  * Works only for OPP v2 bindings.
 904  *
 905  * Returns -ENOENT if operating-points-v2 bindings aren't supported.
 906  */
 907 /**
 908  * dev_pm_opp_of_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with
 909  *                                    @cpu_dev using operating-points-v2
 910  *                                    bindings.
 911  *
 912  * @cpu_dev:    CPU device for which we do this operation
 913  * @cpumask:    cpumask to update with information of sharing CPUs
 914  *
 915  * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev.
 916  *
 917  * Returns -ENOENT if operating-points-v2 isn't present for @cpu_dev.
 918  */
 919 int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev,
 920                                    struct cpumask *cpumask)
 921 {
 922         struct device_node *np, *tmp_np, *cpu_np;
 923         int cpu, ret = 0;
 924
 925         /* Get OPP descriptor node */
 926         np = dev_pm_opp_of_get_opp_desc_node(cpu_dev);
 927         if (!np) {
 928                 dev_dbg(cpu_dev, "%s: Couldn't find opp node.\n", __func__);
 929                 return -ENOENT;
 930         }
 931
 932         cpumask_set_cpu(cpu_dev->id, cpumask);
 933
 934         /* OPPs are shared ? */
 935         if (!of_property_read_bool(np, "opp-shared"))
 936                 goto put_cpu_node;
 937
 938         for_each_possible_cpu(cpu) {
 939                 if (cpu == cpu_dev->id)
 940                         continue;
 941
 942                 cpu_np = of_cpu_device_node_get(cpu);
 943                 if (!cpu_np) {
 944                         dev_err(cpu_dev, "%s: failed to get cpu%d node\n",
 945                                 __func__, cpu);
 946                         ret = -ENOENT;
 947                         goto put_cpu_node;
 948                 }
 949
 950                 /* Get OPP descriptor node */
 951                 tmp_np = _opp_of_get_opp_desc_node(cpu_np, 0);
 952                 of_node_put(cpu_np);
 953                 if (!tmp_np) {
 954                         pr_err("%pOF: Couldn't find opp node\n", cpu_np);
 955                         ret = -ENOENT;
 956                         goto put_cpu_node;
 957                 }
 958
 959                 /* CPUs are sharing opp node */
 960                 if (np == tmp_np)
 961                         cpumask_set_cpu(cpu, cpumask);
 962
 963                 of_node_put(tmp_np);
 964         }
 965
 966 put_cpu_node:
 967         of_node_put(np);
 968         return ret;
 969 }
 970 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus);
 971
 972 /**
 973  * of_get_required_opp_performance_state() - Search for required OPP and return its performance state.
 974  * @np: Node that contains the "required-opps" property.
 975  * @index: Index of the phandle to parse.
 976  *
 977  * Returns the performance state of the OPP pointed out by the "required-opps"
 978  * property at @index in @np.
 979  *
 980  * Return: Positive performance state on success, otherwise 0 on errors.
 981  */
 982 unsigned int of_get_required_opp_performance_state(struct device_node *np,
 983                                                    int index)
 984 {
 985         struct dev_pm_opp *opp;
 986         struct device_node *required_np;
 987         struct opp_table *opp_table;
 988         unsigned int pstate = 0;
 989
 990         required_np = of_parse_required_opp(np, index);
 991         if (!required_np)
 992                 return 0;
 993
 994         opp_table = _find_table_of_opp_np(required_np);
 995         if (IS_ERR(opp_table)) {
 996                 pr_err("%s: Failed to find required OPP table %pOF: %ld\n",
 997                        __func__, np, PTR_ERR(opp_table));
 998                 goto put_required_np;
 999         }
1000
1001         opp = _find_opp_of_np(opp_table, required_np);
1002         if (opp) {
1003                 pstate = opp->pstate;
1004                 dev_pm_opp_put(opp);
1005         }
1006
1007         dev_pm_opp_put_opp_table(opp_table);
1008
1009 put_required_np:
1010         of_node_put(required_np);
1011
1012         return pstate;
1013 }
1014 EXPORT_SYMBOL_GPL(of_get_required_opp_performance_state);
1015
1016 /**
1017  * of_dev_pm_opp_find_required_opp() - Search for required OPP.
1018  * @dev: The device whose OPP node is referenced by the 'np' DT node.
1019  * @np: Node that contains the "required-opps" property.
1020  *
1021  * Returns the OPP of the device 'dev', whose phandle is present in the "np"
1022  * node. Although the "required-opps" property supports having multiple
1023  * phandles, this helper routine only parses the very first phandle in the list.
1024  *
1025  * Return: Matching opp, else returns ERR_PTR in case of error and should be
1026  * handled using IS_ERR.
1027  *
1028  * The callers are required to call dev_pm_opp_put() for the returned OPP after
1029  * use.
1030  */
1031 struct dev_pm_opp *of_dev_pm_opp_find_required_opp(struct device *dev,
1032                                                    struct device_node *np)
1033 {
1034         struct dev_pm_opp *temp_opp, *opp = ERR_PTR(-ENODEV);
1035         struct device_node *required_np;
1036         struct opp_table *opp_table;
1037
1038         opp_table = _find_opp_table(dev);
1039         if (IS_ERR(opp_table))
1040                 return ERR_CAST(opp_table);
1041
1042         required_np = of_parse_phandle(np, "required-opps", 0);
1043         if (unlikely(!required_np)) {
1044                 dev_err(dev, "Unable to parse required-opps\n");
1045                 goto put_opp_table;
1046         }
1047
1048         mutex_lock(&opp_table->lock);
1049
1050         list_for_each_entry(temp_opp, &opp_table->opp_list, node) {
1051                 if (temp_opp->available && temp_opp->np == required_np) {
1052                         opp = temp_opp;
1053
1054                         /* Increment the reference count of OPP */
1055                         dev_pm_opp_get(opp);
1056                         break;
1057                 }
1058         }
1059
1060         mutex_unlock(&opp_table->lock);
1061
1062         of_node_put(required_np);
1063 put_opp_table:
1064         dev_pm_opp_put_opp_table(opp_table);
1065
1066         return opp;
1067 }
1068 EXPORT_SYMBOL_GPL(of_dev_pm_opp_find_required_opp);
1069
1070 /**
1071  * dev_pm_opp_get_of_node() - Gets the DT node corresponding to an opp
1072  * @opp:        opp for which DT node has to be returned for
1073  *
1074  * Return: DT node corresponding to the opp, else 0 on success.
1075  *
1076  * The caller needs to put the node with of_node_put() after using it.
1077  */
1078 struct device_node *dev_pm_opp_get_of_node(struct dev_pm_opp *opp)
1079 {
1080         if (IS_ERR_OR_NULL(opp)) {
1081                 pr_err("%s: Invalid parameters\n", __func__);
1082                 return NULL;
1083         }
1084
1085         return of_node_get(opp->np);
1086 }
1087 EXPORT_SYMBOL_GPL(dev_pm_opp_get_of_node);