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 device_node *opp_table_np;
 118
 119         lockdep_assert_held(&opp_table_lock);
 120
 121         opp_table_np = of_get_parent(opp_np);
 122         if (!opp_table_np)
 123                 goto err;
 124
 125         /* It is safe to put the node now as all we need now is its address */
 126         of_node_put(opp_table_np);
 127
 128         list_for_each_entry(opp_table, &opp_tables, node) {
 129                 if (opp_table_np == opp_table->np) {
 130                         _get_opp_table_kref(opp_table);
 131                         return opp_table;
 132                 }
 133         }
 134
 135 err:
 136         return ERR_PTR(-ENODEV);
 137 }
 138
 139 /* Free resources previously acquired by _opp_table_alloc_required_tables() */
 140 static void _opp_table_free_required_tables(struct opp_table *opp_table)
 141 {
 142         struct opp_table **required_opp_tables = opp_table->required_opp_tables;
 143         struct device **genpd_virt_devs = opp_table->genpd_virt_devs;
 144         int i;
 145
 146         if (!required_opp_tables)
 147                 return;
 148
 149         for (i = 0; i < opp_table->required_opp_count; i++) {
 150                 if (IS_ERR_OR_NULL(required_opp_tables[i]))
 151                         break;
 152
 153                 dev_pm_opp_put_opp_table(required_opp_tables[i]);
 154         }
 155
 156         kfree(required_opp_tables);
 157         kfree(genpd_virt_devs);
 158
 159         opp_table->required_opp_count = 0;
 160         opp_table->genpd_virt_devs = NULL;
 161         opp_table->required_opp_tables = NULL;
 162 }
 163
 164 /*
 165  * Populate all devices and opp tables which are part of "required-opps" list.
 166  * Checking only the first OPP node should be enough.
 167  */
 168 static void _opp_table_alloc_required_tables(struct opp_table *opp_table,
 169                                              struct device *dev,
 170                                              struct device_node *opp_np)
 171 {
 172         struct opp_table **required_opp_tables;
 173         struct device **genpd_virt_devs = NULL;
 174         struct device_node *required_np, *np;
 175         int count, i;
 176
 177         /* Traversing the first OPP node is all we need */
 178         np = of_get_next_available_child(opp_np, NULL);
 179         if (!np) {
 180                 dev_err(dev, "Empty OPP table\n");
 181                 return;
 182         }
 183
 184         count = of_count_phandle_with_args(np, "required-opps", NULL);
 185         if (!count)
 186                 goto put_np;
 187
 188         if (count > 1) {
 189                 genpd_virt_devs = kcalloc(count, sizeof(*genpd_virt_devs),
 190                                         GFP_KERNEL);
 191                 if (!genpd_virt_devs)
 192                         goto put_np;
 193         }
 194
 195         required_opp_tables = kcalloc(count, sizeof(*required_opp_tables),
 196                                       GFP_KERNEL);
 197         if (!required_opp_tables) {
 198                 kfree(genpd_virt_devs);
 199                 goto put_np;
 200         }
 201
 202         opp_table->genpd_virt_devs = genpd_virt_devs;
 203         opp_table->required_opp_tables = required_opp_tables;
 204         opp_table->required_opp_count = count;
 205
 206         for (i = 0; i < count; i++) {
 207                 required_np = of_parse_required_opp(np, i);
 208                 if (!required_np)
 209                         goto free_required_tables;
 210
 211                 required_opp_tables[i] = _find_table_of_opp_np(required_np);
 212                 of_node_put(required_np);
 213
 214                 if (IS_ERR(required_opp_tables[i]))
 215                         goto free_required_tables;
 216
 217                 /*
 218                  * We only support genpd's OPPs in the "required-opps" for now,
 219                  * as we don't know how much about other cases. Error out if the
 220                  * required OPP doesn't belong to a genpd.
 221                  */
 222                 if (!required_opp_tables[i]->is_genpd) {
 223                         dev_err(dev, "required-opp doesn't belong to genpd: %pOF\n",
 224                                 required_np);
 225                         goto free_required_tables;
 226                 }
 227         }
 228
 229         goto put_np;
 230
 231 free_required_tables:
 232         _opp_table_free_required_tables(opp_table);
 233 put_np:
 234         of_node_put(np);
 235 }
 236
 237 void _of_init_opp_table(struct opp_table *opp_table, struct device *dev,
 238                         int index)
 239 {
 240         struct device_node *np, *opp_np;
 241         u32 val;
 242
 243         /*
 244          * Only required for backward compatibility with v1 bindings, but isn't
 245          * harmful for other cases. And so we do it unconditionally.
 246          */
 247         np = of_node_get(dev->of_node);
 248         if (!np)
 249                 return;
 250
 251         if (!of_property_read_u32(np, "clock-latency", &val))
 252                 opp_table->clock_latency_ns_max = val;
 253         of_property_read_u32(np, "voltage-tolerance",
 254                              &opp_table->voltage_tolerance_v1);
 255
 256         if (of_find_property(np, "#power-domain-cells", NULL))
 257                 opp_table->is_genpd = true;
 258
 259         /* Get OPP table node */
 260         opp_np = _opp_of_get_opp_desc_node(np, index);
 261         of_node_put(np);
 262
 263         if (!opp_np)
 264                 return;
 265
 266         if (of_property_read_bool(opp_np, "opp-shared"))
 267                 opp_table->shared_opp = OPP_TABLE_ACCESS_SHARED;
 268         else
 269                 opp_table->shared_opp = OPP_TABLE_ACCESS_EXCLUSIVE;
 270
 271         opp_table->np = opp_np;
 272
 273         _opp_table_alloc_required_tables(opp_table, dev, opp_np);
 274         of_node_put(opp_np);
 275 }
 276
 277 void _of_clear_opp_table(struct opp_table *opp_table)
 278 {
 279         _opp_table_free_required_tables(opp_table);
 280 }
 281
 282 /*
 283  * Release all resources previously acquired with a call to
 284  * _of_opp_alloc_required_opps().
 285  */
 286 void _of_opp_free_required_opps(struct opp_table *opp_table,
 287                                 struct dev_pm_opp *opp)
 288 {
 289         struct dev_pm_opp **required_opps = opp->required_opps;
 290         int i;
 291
 292         if (!required_opps)
 293                 return;
 294
 295         for (i = 0; i < opp_table->required_opp_count; i++) {
 296                 if (!required_opps[i])
 297                         break;
 298
 299                 /* Put the reference back */
 300                 dev_pm_opp_put(required_opps[i]);
 301         }
 302
 303         kfree(required_opps);
 304         opp->required_opps = NULL;
 305 }
 306
 307 /* Populate all required OPPs which are part of "required-opps" list */
 308 static int _of_opp_alloc_required_opps(struct opp_table *opp_table,
 309                                        struct dev_pm_opp *opp)
 310 {
 311         struct dev_pm_opp **required_opps;
 312         struct opp_table *required_table;
 313         struct device_node *np;
 314         int i, ret, count = opp_table->required_opp_count;
 315
 316         if (!count)
 317                 return 0;
 318
 319         required_opps = kcalloc(count, sizeof(*required_opps), GFP_KERNEL);
 320         if (!required_opps)
 321                 return -ENOMEM;
 322
 323         opp->required_opps = required_opps;
 324
 325         for (i = 0; i < count; i++) {
 326                 required_table = opp_table->required_opp_tables[i];
 327
 328                 np = of_parse_required_opp(opp->np, i);
 329                 if (unlikely(!np)) {
 330                         ret = -ENODEV;
 331                         goto free_required_opps;
 332                 }
 333
 334                 required_opps[i] = _find_opp_of_np(required_table, np);
 335                 of_node_put(np);
 336
 337                 if (!required_opps[i]) {
 338                         pr_err("%s: Unable to find required OPP node: %pOF (%d)\n",
 339                                __func__, opp->np, i);
 340                         ret = -ENODEV;
 341                         goto free_required_opps;
 342                 }
 343         }
 344
 345         return 0;
 346
 347 free_required_opps:
 348         _of_opp_free_required_opps(opp_table, opp);
 349
 350         return ret;
 351 }
 352
 353 static bool _opp_is_supported(struct device *dev, struct opp_table *opp_table,
 354                               struct device_node *np)
 355 {
 356         unsigned int count = opp_table->supported_hw_count;
 357         u32 version;
 358         int ret;
 359
 360         if (!opp_table->supported_hw) {
 361                 /*
 362                  * In the case that no supported_hw has been set by the
 363                  * platform but there is an opp-supported-hw value set for
 364                  * an OPP then the OPP should not be enabled as there is
 365                  * no way to see if the hardware supports it.
 366                  */
 367                 if (of_find_property(np, "opp-supported-hw", NULL))
 368                         return false;
 369                 else
 370                         return true;
 371         }
 372
 373         while (count--) {
 374                 ret = of_property_read_u32_index(np, "opp-supported-hw", count,
 375                                                  &version);
 376                 if (ret) {
 377                         dev_warn(dev, "%s: failed to read opp-supported-hw property at index %d: %d\n",
 378                                  __func__, count, ret);
 379                         return false;
 380                 }
 381
 382                 /* Both of these are bitwise masks of the versions */
 383                 if (!(version & opp_table->supported_hw[count]))
 384                         return false;
 385         }
 386
 387         return true;
 388 }
 389
 390 static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,
 391                               struct opp_table *opp_table)
 392 {
 393         u32 *microvolt, *microamp = NULL;
 394         int supplies = opp_table->regulator_count, vcount, icount, ret, i, j;
 395         struct property *prop = NULL;
 396         char name[NAME_MAX];
 397
 398         /* Search for "opp-microvolt-<name>" */
 399         if (opp_table->prop_name) {
 400                 snprintf(name, sizeof(name), "opp-microvolt-%s",
 401                          opp_table->prop_name);
 402                 prop = of_find_property(opp->np, name, NULL);
 403         }
 404
 405         if (!prop) {
 406                 /* Search for "opp-microvolt" */
 407                 sprintf(name, "opp-microvolt");
 408                 prop = of_find_property(opp->np, name, NULL);
 409
 410                 /* Missing property isn't a problem, but an invalid entry is */
 411                 if (!prop) {
 412                         if (unlikely(supplies == -1)) {
 413                                 /* Initialize regulator_count */
 414                                 opp_table->regulator_count = 0;
 415                                 return 0;
 416                         }
 417
 418                         if (!supplies)
 419                                 return 0;
 420
 421                         dev_err(dev, "%s: opp-microvolt missing although OPP managing regulators\n",
 422                                 __func__);
 423                         return -EINVAL;
 424                 }
 425         }
 426
 427         if (unlikely(supplies == -1)) {
 428                 /* Initialize regulator_count */
 429                 supplies = opp_table->regulator_count = 1;
 430         } else if (unlikely(!supplies)) {
 431                 dev_err(dev, "%s: opp-microvolt wasn't expected\n", __func__);
 432                 return -EINVAL;
 433         }
 434
 435         vcount = of_property_count_u32_elems(opp->np, name);
 436         if (vcount < 0) {
 437                 dev_err(dev, "%s: Invalid %s property (%d)\n",
 438                         __func__, name, vcount);
 439                 return vcount;
 440         }
 441
 442         /* There can be one or three elements per supply */
 443         if (vcount != supplies && vcount != supplies * 3) {
 444                 dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
 445                         __func__, name, vcount, supplies);
 446                 return -EINVAL;
 447         }
 448
 449         microvolt = kmalloc_array(vcount, sizeof(*microvolt), GFP_KERNEL);
 450         if (!microvolt)
 451                 return -ENOMEM;
 452
 453         ret = of_property_read_u32_array(opp->np, name, microvolt, vcount);
 454         if (ret) {
 455                 dev_err(dev, "%s: error parsing %s: %d\n", __func__, name, ret);
 456                 ret = -EINVAL;
 457                 goto free_microvolt;
 458         }
 459
 460         /* Search for "opp-microamp-<name>" */
 461         prop = NULL;
 462         if (opp_table->prop_name) {
 463                 snprintf(name, sizeof(name), "opp-microamp-%s",
 464                          opp_table->prop_name);
 465                 prop = of_find_property(opp->np, name, NULL);
 466         }
 467
 468         if (!prop) {
 469                 /* Search for "opp-microamp" */
 470                 sprintf(name, "opp-microamp");
 471                 prop = of_find_property(opp->np, name, NULL);
 472         }
 473
 474         if (prop) {
 475                 icount = of_property_count_u32_elems(opp->np, name);
 476                 if (icount < 0) {
 477                         dev_err(dev, "%s: Invalid %s property (%d)\n", __func__,
 478                                 name, icount);
 479                         ret = icount;
 480                         goto free_microvolt;
 481                 }
 482
 483                 if (icount != supplies) {
 484                         dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
 485                                 __func__, name, icount, supplies);
 486                         ret = -EINVAL;
 487                         goto free_microvolt;
 488                 }
 489
 490                 microamp = kmalloc_array(icount, sizeof(*microamp), GFP_KERNEL);
 491                 if (!microamp) {
 492                         ret = -EINVAL;
 493                         goto free_microvolt;
 494                 }
 495
 496                 ret = of_property_read_u32_array(opp->np, name, microamp,
 497                                                  icount);
 498                 if (ret) {
 499                         dev_err(dev, "%s: error parsing %s: %d\n", __func__,
 500                                 name, ret);
 501                         ret = -EINVAL;
 502                         goto free_microamp;
 503                 }
 504         }
 505
 506         for (i = 0, j = 0; i < supplies; i++) {
 507                 opp->supplies[i].u_volt = microvolt[j++];
 508
 509                 if (vcount == supplies) {
 510                         opp->supplies[i].u_volt_min = opp->supplies[i].u_volt;
 511                         opp->supplies[i].u_volt_max = opp->supplies[i].u_volt;
 512                 } else {
 513                         opp->supplies[i].u_volt_min = microvolt[j++];
 514                         opp->supplies[i].u_volt_max = microvolt[j++];
 515                 }
 516
 517                 if (microamp)
 518                         opp->supplies[i].u_amp = microamp[i];
 519         }
 520
 521 free_microamp:
 522         kfree(microamp);
 523 free_microvolt:
 524         kfree(microvolt);
 525
 526         return ret;
 527 }
 528
 529 /**
 530  * dev_pm_opp_of_remove_table() - Free OPP table entries created from static DT
 531  *                                entries
 532  * @dev:        device pointer used to lookup OPP table.
 533  *
 534  * Free OPPs created using static entries present in DT.
 535  */
 536 void dev_pm_opp_of_remove_table(struct device *dev)
 537 {
 538         _dev_pm_opp_find_and_remove_table(dev);
 539 }
 540 EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table);
 541
 542 /**
 543  * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings)
 544  * @opp_table:  OPP table
 545  * @dev:        device for which we do this operation
 546  * @np:         device node
 547  *
 548  * This function adds an opp definition to the opp table and returns status. The
 549  * opp can be controlled using dev_pm_opp_enable/disable functions and may be
 550  * removed by dev_pm_opp_remove.
 551  *
 552  * Return:
 553  * Valid OPP pointer:
 554  *              On success
 555  * NULL:
 556  *              Duplicate OPPs (both freq and volt are same) and opp->available
 557  *              OR if the OPP is not supported by hardware.
 558  * ERR_PTR(-EEXIST):
 559  *              Freq are same and volt are different OR
 560  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 561  * ERR_PTR(-ENOMEM):
 562  *              Memory allocation failure
 563  * ERR_PTR(-EINVAL):
 564  *              Failed parsing the OPP node
 565  */
 566 static struct dev_pm_opp *_opp_add_static_v2(struct opp_table *opp_table,
 567                 struct device *dev, struct device_node *np)
 568 {
 569         struct dev_pm_opp *new_opp;
 570         u64 rate = 0;
 571         u32 val;
 572         int ret;
 573         bool rate_not_available = false;
 574
 575         new_opp = _opp_allocate(opp_table);
 576         if (!new_opp)
 577                 return ERR_PTR(-ENOMEM);
 578
 579         ret = of_property_read_u64(np, "opp-hz", &rate);
 580         if (ret < 0) {
 581                 /* "opp-hz" is optional for devices like power domains. */
 582                 if (!opp_table->is_genpd) {
 583                         dev_err(dev, "%s: opp-hz not found\n", __func__);
 584                         goto free_opp;
 585                 }
 586
 587                 rate_not_available = true;
 588         } else {
 589                 /*
 590                  * Rate is defined as an unsigned long in clk API, and so
 591                  * casting explicitly to its type. Must be fixed once rate is 64
 592                  * bit guaranteed in clk API.
 593                  */
 594                 new_opp->rate = (unsigned long)rate;
 595         }
 596
 597         /* Check if the OPP supports hardware's hierarchy of versions or not */
 598         if (!_opp_is_supported(dev, opp_table, np)) {
 599                 dev_dbg(dev, "OPP not supported by hardware: %llu\n", rate);
 600                 goto free_opp;
 601         }
 602
 603         new_opp->turbo = of_property_read_bool(np, "turbo-mode");
 604
 605         new_opp->np = np;
 606         new_opp->dynamic = false;
 607         new_opp->available = true;
 608
 609         ret = _of_opp_alloc_required_opps(opp_table, new_opp);
 610         if (ret)
 611                 goto free_opp;
 612
 613         if (!of_property_read_u32(np, "clock-latency-ns", &val))
 614                 new_opp->clock_latency_ns = val;
 615
 616         ret = opp_parse_supplies(new_opp, dev, opp_table);
 617         if (ret)
 618                 goto free_required_opps;
 619
 620         if (opp_table->is_genpd)
 621                 new_opp->pstate = pm_genpd_opp_to_performance_state(dev, new_opp);
 622
 623         ret = _opp_add(dev, new_opp, opp_table, rate_not_available);
 624         if (ret) {
 625                 /* Don't return error for duplicate OPPs */
 626                 if (ret == -EBUSY)
 627                         ret = 0;
 628                 goto free_required_opps;
 629         }
 630
 631         /* OPP to select on device suspend */
 632         if (of_property_read_bool(np, "opp-suspend")) {
 633                 if (opp_table->suspend_opp) {
 634                         dev_warn(dev, "%s: Multiple suspend OPPs found (%lu %lu)\n",
 635                                  __func__, opp_table->suspend_opp->rate,
 636                                  new_opp->rate);
 637                 } else {
 638                         new_opp->suspend = true;
 639                         opp_table->suspend_opp = new_opp;
 640                 }
 641         }
 642
 643         if (new_opp->clock_latency_ns > opp_table->clock_latency_ns_max)
 644                 opp_table->clock_latency_ns_max = new_opp->clock_latency_ns;
 645
 646         pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu\n",
 647                  __func__, new_opp->turbo, new_opp->rate,
 648                  new_opp->supplies[0].u_volt, new_opp->supplies[0].u_volt_min,
 649                  new_opp->supplies[0].u_volt_max, new_opp->clock_latency_ns);
 650
 651         /*
 652          * Notify the changes in the availability of the operable
 653          * frequency/voltage list.
 654          */
 655         blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ADD, new_opp);
 656         return new_opp;
 657
 658 free_required_opps:
 659         _of_opp_free_required_opps(opp_table, new_opp);
 660 free_opp:
 661         _opp_free(new_opp);
 662
 663         return ERR_PTR(ret);
 664 }
 665
 666 /* Initializes OPP tables based on new bindings */
 667 static int _of_add_opp_table_v2(struct device *dev, struct opp_table *opp_table)
 668 {
 669         struct device_node *np;
 670         int ret, count = 0, pstate_count = 0;
 671         struct dev_pm_opp *opp;
 672
 673         /* OPP table is already initialized for the device */
 674         if (opp_table->parsed_static_opps) {
 675                 kref_get(&opp_table->list_kref);
 676                 return 0;
 677         }
 678
 679         kref_init(&opp_table->list_kref);
 680
 681         /* We have opp-table node now, iterate over it and add OPPs */
 682         for_each_available_child_of_node(opp_table->np, np) {
 683                 opp = _opp_add_static_v2(opp_table, dev, np);
 684                 if (IS_ERR(opp)) {
 685                         ret = PTR_ERR(opp);
 686                         dev_err(dev, "%s: Failed to add OPP, %d\n", __func__,
 687                                 ret);
 688                         of_node_put(np);
 689                         goto put_list_kref;
 690                 } else if (opp) {
 691                         count++;
 692                 }
 693         }
 694
 695         /* There should be one of more OPP defined */
 696         if (WARN_ON(!count)) {
 697                 ret = -ENOENT;
 698                 goto put_list_kref;
 699         }
 700
 701         list_for_each_entry(opp, &opp_table->opp_list, node)
 702                 pstate_count += !!opp->pstate;
 703
 704         /* Either all or none of the nodes shall have performance state set */
 705         if (pstate_count && pstate_count != count) {
 706                 dev_err(dev, "Not all nodes have performance state set (%d: %d)\n",
 707                         count, pstate_count);
 708                 ret = -ENOENT;
 709                 goto put_list_kref;
 710         }
 711
 712         if (pstate_count)
 713                 opp_table->genpd_performance_state = true;
 714
 715         opp_table->parsed_static_opps = true;
 716
 717         return 0;
 718
 719 put_list_kref:
 720         _put_opp_list_kref(opp_table);
 721
 722         return ret;
 723 }
 724
 725 /* Initializes OPP tables based on old-deprecated bindings */
 726 static int _of_add_opp_table_v1(struct device *dev, struct opp_table *opp_table)
 727 {
 728         const struct property *prop;
 729         const __be32 *val;
 730         int nr, ret = 0;
 731
 732         prop = of_find_property(dev->of_node, "operating-points", NULL);
 733         if (!prop)
 734                 return -ENODEV;
 735         if (!prop->value)
 736                 return -ENODATA;
 737
 738         /*
 739          * Each OPP is a set of tuples consisting of frequency and
 740          * voltage like <freq-kHz vol-uV>.
 741          */
 742         nr = prop->length / sizeof(u32);
 743         if (nr % 2) {
 744                 dev_err(dev, "%s: Invalid OPP table\n", __func__);
 745                 return -EINVAL;
 746         }
 747
 748         kref_init(&opp_table->list_kref);
 749
 750         val = prop->value;
 751         while (nr) {
 752                 unsigned long freq = be32_to_cpup(val++) * 1000;
 753                 unsigned long volt = be32_to_cpup(val++);
 754
 755                 ret = _opp_add_v1(opp_table, dev, freq, volt, false);
 756                 if (ret) {
 757                         dev_err(dev, "%s: Failed to add OPP %ld (%d)\n",
 758                                 __func__, freq, ret);
 759                         _put_opp_list_kref(opp_table);
 760                         return ret;
 761                 }
 762                 nr -= 2;
 763         }
 764
 765         return ret;
 766 }
 767
 768 /**
 769  * dev_pm_opp_of_add_table() - Initialize opp table from device tree
 770  * @dev:        device pointer used to lookup OPP table.
 771  *
 772  * Register the initial OPP table with the OPP library for given device.
 773  *
 774  * Return:
 775  * 0            On success OR
 776  *              Duplicate OPPs (both freq and volt are same) and opp->available
 777  * -EEXIST      Freq are same and volt are different OR
 778  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 779  * -ENOMEM      Memory allocation failure
 780  * -ENODEV      when 'operating-points' property is not found or is invalid data
 781  *              in device node.
 782  * -ENODATA     when empty 'operating-points' property is found
 783  * -EINVAL      when invalid entries are found in opp-v2 table
 784  */
 785 int dev_pm_opp_of_add_table(struct device *dev)
 786 {
 787         struct opp_table *opp_table;
 788         int ret;
 789
 790         opp_table = dev_pm_opp_get_opp_table_indexed(dev, 0);
 791         if (!opp_table)
 792                 return -ENOMEM;
 793
 794         /*
 795          * OPPs have two version of bindings now. Also try the old (v1)
 796          * bindings for backward compatibility with older dtbs.
 797          */
 798         if (opp_table->np)
 799                 ret = _of_add_opp_table_v2(dev, opp_table);
 800         else
 801                 ret = _of_add_opp_table_v1(dev, opp_table);
 802
 803         if (ret)
 804                 dev_pm_opp_put_opp_table(opp_table);
 805
 806         return ret;
 807 }
 808 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table);
 809
 810 /**
 811  * dev_pm_opp_of_add_table_indexed() - Initialize indexed opp table from device tree
 812  * @dev:        device pointer used to lookup OPP table.
 813  * @index:      Index number.
 814  *
 815  * Register the initial OPP table with the OPP library for given device only
 816  * using the "operating-points-v2" property.
 817  *
 818  * Return:
 819  * 0            On success OR
 820  *              Duplicate OPPs (both freq and volt are same) and opp->available
 821  * -EEXIST      Freq are same and volt are different OR
 822  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 823  * -ENOMEM      Memory allocation failure
 824  * -ENODEV      when 'operating-points' property is not found or is invalid data
 825  *              in device node.
 826  * -ENODATA     when empty 'operating-points' property is found
 827  * -EINVAL      when invalid entries are found in opp-v2 table
 828  */
 829 int dev_pm_opp_of_add_table_indexed(struct device *dev, int index)
 830 {
 831         struct opp_table *opp_table;
 832         int ret, count;
 833
 834         if (index) {
 835                 /*
 836                  * If only one phandle is present, then the same OPP table
 837                  * applies for all index requests.
 838                  */
 839                 count = of_count_phandle_with_args(dev->of_node,
 840                                                    "operating-points-v2", NULL);
 841                 if (count == 1)
 842                         index = 0;
 843         }
 844
 845         opp_table = dev_pm_opp_get_opp_table_indexed(dev, index);
 846         if (!opp_table)
 847                 return -ENOMEM;
 848
 849         ret = _of_add_opp_table_v2(dev, opp_table);
 850         if (ret)
 851                 dev_pm_opp_put_opp_table(opp_table);
 852
 853         return ret;
 854 }
 855 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table_indexed);
 856
 857 /* CPU device specific helpers */
 858
 859 /**
 860  * dev_pm_opp_of_cpumask_remove_table() - Removes OPP table for @cpumask
 861  * @cpumask:    cpumask for which OPP table needs to be removed
 862  *
 863  * This removes the OPP tables for CPUs present in the @cpumask.
 864  * This should be used only to remove static entries created from DT.
 865  */
 866 void dev_pm_opp_of_cpumask_remove_table(const struct cpumask *cpumask)
 867 {
 868         _dev_pm_opp_cpumask_remove_table(cpumask, -1);
 869 }
 870 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_remove_table);
 871
 872 /**
 873  * dev_pm_opp_of_cpumask_add_table() - Adds OPP table for @cpumask
 874  * @cpumask:    cpumask for which OPP table needs to be added.
 875  *
 876  * This adds the OPP tables for CPUs present in the @cpumask.
 877  */
 878 int dev_pm_opp_of_cpumask_add_table(const struct cpumask *cpumask)
 879 {
 880         struct device *cpu_dev;
 881         int cpu, ret;
 882
 883         if (WARN_ON(cpumask_empty(cpumask)))
 884                 return -ENODEV;
 885
 886         for_each_cpu(cpu, cpumask) {
 887                 cpu_dev = get_cpu_device(cpu);
 888                 if (!cpu_dev) {
 889                         pr_err("%s: failed to get cpu%d device\n", __func__,
 890                                cpu);
 891                         ret = -ENODEV;
 892                         goto remove_table;
 893                 }
 894
 895                 ret = dev_pm_opp_of_add_table(cpu_dev);
 896                 if (ret) {
 897                         /*
 898                          * OPP may get registered dynamically, don't print error
 899                          * message here.
 900                          */
 901                         pr_debug("%s: couldn't find opp table for cpu:%d, %d\n",
 902                                  __func__, cpu, ret);
 903
 904                         goto remove_table;
 905                 }
 906         }
 907
 908         return 0;
 909
 910 remove_table:
 911         /* Free all other OPPs */
 912         _dev_pm_opp_cpumask_remove_table(cpumask, cpu);
 913
 914         return ret;
 915 }
 916 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_add_table);
 917
 918 /*
 919  * Works only for OPP v2 bindings.
 920  *
 921  * Returns -ENOENT if operating-points-v2 bindings aren't supported.
 922  */
 923 /**
 924  * dev_pm_opp_of_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with
 925  *                                    @cpu_dev using operating-points-v2
 926  *                                    bindings.
 927  *
 928  * @cpu_dev:    CPU device for which we do this operation
 929  * @cpumask:    cpumask to update with information of sharing CPUs
 930  *
 931  * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev.
 932  *
 933  * Returns -ENOENT if operating-points-v2 isn't present for @cpu_dev.
 934  */
 935 int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev,
 936                                    struct cpumask *cpumask)
 937 {
 938         struct device_node *np, *tmp_np, *cpu_np;
 939         int cpu, ret = 0;
 940
 941         /* Get OPP descriptor node */
 942         np = dev_pm_opp_of_get_opp_desc_node(cpu_dev);
 943         if (!np) {
 944                 dev_dbg(cpu_dev, "%s: Couldn't find opp node.\n", __func__);
 945                 return -ENOENT;
 946         }
 947
 948         cpumask_set_cpu(cpu_dev->id, cpumask);
 949
 950         /* OPPs are shared ? */
 951         if (!of_property_read_bool(np, "opp-shared"))
 952                 goto put_cpu_node;
 953
 954         for_each_possible_cpu(cpu) {
 955                 if (cpu == cpu_dev->id)
 956                         continue;
 957
 958                 cpu_np = of_cpu_device_node_get(cpu);
 959                 if (!cpu_np) {
 960                         dev_err(cpu_dev, "%s: failed to get cpu%d node\n",
 961                                 __func__, cpu);
 962                         ret = -ENOENT;
 963                         goto put_cpu_node;
 964                 }
 965
 966                 /* Get OPP descriptor node */
 967                 tmp_np = _opp_of_get_opp_desc_node(cpu_np, 0);
 968                 of_node_put(cpu_np);
 969                 if (!tmp_np) {
 970                         pr_err("%pOF: Couldn't find opp node\n", cpu_np);
 971                         ret = -ENOENT;
 972                         goto put_cpu_node;
 973                 }
 974
 975                 /* CPUs are sharing opp node */
 976                 if (np == tmp_np)
 977                         cpumask_set_cpu(cpu, cpumask);
 978
 979                 of_node_put(tmp_np);
 980         }
 981
 982 put_cpu_node:
 983         of_node_put(np);
 984         return ret;
 985 }
 986 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus);
 987
 988 /**
 989  * of_get_required_opp_performance_state() - Search for required OPP and return its performance state.
 990  * @np: Node that contains the "required-opps" property.
 991  * @index: Index of the phandle to parse.
 992  *
 993  * Returns the performance state of the OPP pointed out by the "required-opps"
 994  * property at @index in @np.
 995  *
 996  * Return: Zero or positive performance state on success, otherwise negative
 997  * value on errors.
 998  */
 999 int of_get_required_opp_performance_state(struct device_node *np, int index)
1000 {
1001         struct dev_pm_opp *opp;
1002         struct device_node *required_np;
1003         struct opp_table *opp_table;
1004         int pstate = -EINVAL;
1005
1006         required_np = of_parse_required_opp(np, index);
1007         if (!required_np)
1008                 return -EINVAL;
1009
1010         opp_table = _find_table_of_opp_np(required_np);
1011         if (IS_ERR(opp_table)) {
1012                 pr_err("%s: Failed to find required OPP table %pOF: %ld\n",
1013                        __func__, np, PTR_ERR(opp_table));
1014                 goto put_required_np;
1015         }
1016
1017         opp = _find_opp_of_np(opp_table, required_np);
1018         if (opp) {
1019                 pstate = opp->pstate;
1020                 dev_pm_opp_put(opp);
1021         }
1022
1023         dev_pm_opp_put_opp_table(opp_table);
1024
1025 put_required_np:
1026         of_node_put(required_np);
1027
1028         return pstate;
1029 }
1030 EXPORT_SYMBOL_GPL(of_get_required_opp_performance_state);
1031
1032 /**
1033  * dev_pm_opp_get_of_node() - Gets the DT node corresponding to an opp
1034  * @opp:        opp for which DT node has to be returned for
1035  *
1036  * Return: DT node corresponding to the opp, else 0 on success.
1037  *
1038  * The caller needs to put the node with of_node_put() after using it.
1039  */
1040 struct device_node *dev_pm_opp_get_of_node(struct dev_pm_opp *opp)
1041 {
1042         if (IS_ERR_OR_NULL(opp)) {
1043                 pr_err("%s: Invalid parameters\n", __func__);
1044                 return NULL;
1045         }
1046
1047         return of_node_get(opp->np);
1048 }
1049 EXPORT_SYMBOL_GPL(dev_pm_opp_get_of_node);