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 #include <linux/energy_model.h>
  24
  25 #include "opp.h"
  26
  27 /*
  28  * Returns opp descriptor node for a device node, caller must
  29  * do of_node_put().
  30  */
  31 static struct device_node *_opp_of_get_opp_desc_node(struct device_node *np,
  32                                                      int index)
  33 {
  34         /* "operating-points-v2" can be an array for power domain providers */
  35         return of_parse_phandle(np, "operating-points-v2", index);
  36 }
  37
  38 /* Returns opp descriptor node for a device, caller must do of_node_put() */
  39 struct device_node *dev_pm_opp_of_get_opp_desc_node(struct device *dev)
  40 {
  41         return _opp_of_get_opp_desc_node(dev->of_node, 0);
  42 }
  43 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_opp_desc_node);
  44
  45 struct opp_table *_managed_opp(struct device *dev, int index)
  46 {
  47         struct opp_table *opp_table, *managed_table = NULL;
  48         struct device_node *np;
  49
  50         np = _opp_of_get_opp_desc_node(dev->of_node, index);
  51         if (!np)
  52                 return NULL;
  53
  54         list_for_each_entry(opp_table, &opp_tables, node) {
  55                 if (opp_table->np == np) {
  56                         /*
  57                          * Multiple devices can point to the same OPP table and
  58                          * so will have same node-pointer, np.
  59                          *
  60                          * But the OPPs will be considered as shared only if the
  61                          * OPP table contains a "opp-shared" property.
  62                          */
  63                         if (opp_table->shared_opp == OPP_TABLE_ACCESS_SHARED) {
  64                                 _get_opp_table_kref(opp_table);
  65                                 managed_table = opp_table;
  66                         }
  67
  68                         break;
  69                 }
  70         }
  71
  72         of_node_put(np);
  73
  74         return managed_table;
  75 }
  76
  77 /* The caller must call dev_pm_opp_put() after the OPP is used */
  78 static struct dev_pm_opp *_find_opp_of_np(struct opp_table *opp_table,
  79                                           struct device_node *opp_np)
  80 {
  81         struct dev_pm_opp *opp;
  82
  83         lockdep_assert_held(&opp_table_lock);
  84
  85         mutex_lock(&opp_table->lock);
  86
  87         list_for_each_entry(opp, &opp_table->opp_list, node) {
  88                 if (opp->np == opp_np) {
  89                         dev_pm_opp_get(opp);
  90                         mutex_unlock(&opp_table->lock);
  91                         return opp;
  92                 }
  93         }
  94
  95         mutex_unlock(&opp_table->lock);
  96
  97         return NULL;
  98 }
  99
 100 static struct device_node *of_parse_required_opp(struct device_node *np,
 101                                                  int index)
 102 {
 103         struct device_node *required_np;
 104
 105         required_np = of_parse_phandle(np, "required-opps", index);
 106         if (unlikely(!required_np)) {
 107                 pr_err("%s: Unable to parse required-opps: %pOF, index: %d\n",
 108                        __func__, np, index);
 109         }
 110
 111         return required_np;
 112 }
 113
 114 /* The caller must call dev_pm_opp_put_opp_table() after the table is used */
 115 static struct opp_table *_find_table_of_opp_np(struct device_node *opp_np)
 116 {
 117         struct opp_table *opp_table;
 118         struct device_node *opp_table_np;
 119
 120         lockdep_assert_held(&opp_table_lock);
 121
 122         opp_table_np = of_get_parent(opp_np);
 123         if (!opp_table_np)
 124                 goto err;
 125
 126         /* It is safe to put the node now as all we need now is its address */
 127         of_node_put(opp_table_np);
 128
 129         list_for_each_entry(opp_table, &opp_tables, node) {
 130                 if (opp_table_np == opp_table->np) {
 131                         _get_opp_table_kref(opp_table);
 132                         return opp_table;
 133                 }
 134         }
 135
 136 err:
 137         return ERR_PTR(-ENODEV);
 138 }
 139
 140 /* Free resources previously acquired by _opp_table_alloc_required_tables() */
 141 static void _opp_table_free_required_tables(struct opp_table *opp_table)
 142 {
 143         struct opp_table **required_opp_tables = opp_table->required_opp_tables;
 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
 158         opp_table->required_opp_count = 0;
 159         opp_table->required_opp_tables = NULL;
 160 }
 161
 162 /*
 163  * Populate all devices and opp tables which are part of "required-opps" list.
 164  * Checking only the first OPP node should be enough.
 165  */
 166 static void _opp_table_alloc_required_tables(struct opp_table *opp_table,
 167                                              struct device *dev,
 168                                              struct device_node *opp_np)
 169 {
 170         struct opp_table **required_opp_tables;
 171         struct device_node *required_np, *np;
 172         int count, i;
 173
 174         /* Traversing the first OPP node is all we need */
 175         np = of_get_next_available_child(opp_np, NULL);
 176         if (!np) {
 177                 dev_err(dev, "Empty OPP table\n");
 178                 return;
 179         }
 180
 181         count = of_count_phandle_with_args(np, "required-opps", NULL);
 182         if (!count)
 183                 goto put_np;
 184
 185         required_opp_tables = kcalloc(count, sizeof(*required_opp_tables),
 186                                       GFP_KERNEL);
 187         if (!required_opp_tables)
 188                 goto put_np;
 189
 190         opp_table->required_opp_tables = required_opp_tables;
 191         opp_table->required_opp_count = count;
 192
 193         for (i = 0; i < count; i++) {
 194                 required_np = of_parse_required_opp(np, i);
 195                 if (!required_np)
 196                         goto free_required_tables;
 197
 198                 required_opp_tables[i] = _find_table_of_opp_np(required_np);
 199                 of_node_put(required_np);
 200
 201                 if (IS_ERR(required_opp_tables[i]))
 202                         goto free_required_tables;
 203
 204                 /*
 205                  * We only support genpd's OPPs in the "required-opps" for now,
 206                  * as we don't know how much about other cases. Error out if the
 207                  * required OPP doesn't belong to a genpd.
 208                  */
 209                 if (!required_opp_tables[i]->is_genpd) {
 210                         dev_err(dev, "required-opp doesn't belong to genpd: %pOF\n",
 211                                 required_np);
 212                         goto free_required_tables;
 213                 }
 214         }
 215
 216         goto put_np;
 217
 218 free_required_tables:
 219         _opp_table_free_required_tables(opp_table);
 220 put_np:
 221         of_node_put(np);
 222 }
 223
 224 void _of_init_opp_table(struct opp_table *opp_table, struct device *dev,
 225                         int index)
 226 {
 227         struct device_node *np, *opp_np;
 228         u32 val;
 229
 230         /*
 231          * Only required for backward compatibility with v1 bindings, but isn't
 232          * harmful for other cases. And so we do it unconditionally.
 233          */
 234         np = of_node_get(dev->of_node);
 235         if (!np)
 236                 return;
 237
 238         if (!of_property_read_u32(np, "clock-latency", &val))
 239                 opp_table->clock_latency_ns_max = val;
 240         of_property_read_u32(np, "voltage-tolerance",
 241                              &opp_table->voltage_tolerance_v1);
 242
 243         if (of_find_property(np, "#power-domain-cells", NULL))
 244                 opp_table->is_genpd = true;
 245
 246         /* Get OPP table node */
 247         opp_np = _opp_of_get_opp_desc_node(np, index);
 248         of_node_put(np);
 249
 250         if (!opp_np)
 251                 return;
 252
 253         if (of_property_read_bool(opp_np, "opp-shared"))
 254                 opp_table->shared_opp = OPP_TABLE_ACCESS_SHARED;
 255         else
 256                 opp_table->shared_opp = OPP_TABLE_ACCESS_EXCLUSIVE;
 257
 258         opp_table->np = opp_np;
 259
 260         _opp_table_alloc_required_tables(opp_table, dev, opp_np);
 261         of_node_put(opp_np);
 262 }
 263
 264 void _of_clear_opp_table(struct opp_table *opp_table)
 265 {
 266         _opp_table_free_required_tables(opp_table);
 267 }
 268
 269 /*
 270  * Release all resources previously acquired with a call to
 271  * _of_opp_alloc_required_opps().
 272  */
 273 void _of_opp_free_required_opps(struct opp_table *opp_table,
 274                                 struct dev_pm_opp *opp)
 275 {
 276         struct dev_pm_opp **required_opps = opp->required_opps;
 277         int i;
 278
 279         if (!required_opps)
 280                 return;
 281
 282         for (i = 0; i < opp_table->required_opp_count; i++) {
 283                 if (!required_opps[i])
 284                         break;
 285
 286                 /* Put the reference back */
 287                 dev_pm_opp_put(required_opps[i]);
 288         }
 289
 290         kfree(required_opps);
 291         opp->required_opps = NULL;
 292 }
 293
 294 /* Populate all required OPPs which are part of "required-opps" list */
 295 static int _of_opp_alloc_required_opps(struct opp_table *opp_table,
 296                                        struct dev_pm_opp *opp)
 297 {
 298         struct dev_pm_opp **required_opps;
 299         struct opp_table *required_table;
 300         struct device_node *np;
 301         int i, ret, count = opp_table->required_opp_count;
 302
 303         if (!count)
 304                 return 0;
 305
 306         required_opps = kcalloc(count, sizeof(*required_opps), GFP_KERNEL);
 307         if (!required_opps)
 308                 return -ENOMEM;
 309
 310         opp->required_opps = required_opps;
 311
 312         for (i = 0; i < count; i++) {
 313                 required_table = opp_table->required_opp_tables[i];
 314
 315                 np = of_parse_required_opp(opp->np, i);
 316                 if (unlikely(!np)) {
 317                         ret = -ENODEV;
 318                         goto free_required_opps;
 319                 }
 320
 321                 required_opps[i] = _find_opp_of_np(required_table, np);
 322                 of_node_put(np);
 323
 324                 if (!required_opps[i]) {
 325                         pr_err("%s: Unable to find required OPP node: %pOF (%d)\n",
 326                                __func__, opp->np, i);
 327                         ret = -ENODEV;
 328                         goto free_required_opps;
 329                 }
 330         }
 331
 332         return 0;
 333
 334 free_required_opps:
 335         _of_opp_free_required_opps(opp_table, opp);
 336
 337         return ret;
 338 }
 339
 340 static bool _opp_is_supported(struct device *dev, struct opp_table *opp_table,
 341                               struct device_node *np)
 342 {
 343         unsigned int count = opp_table->supported_hw_count;
 344         u32 version;
 345         int ret;
 346
 347         if (!opp_table->supported_hw) {
 348                 /*
 349                  * In the case that no supported_hw has been set by the
 350                  * platform but there is an opp-supported-hw value set for
 351                  * an OPP then the OPP should not be enabled as there is
 352                  * no way to see if the hardware supports it.
 353                  */
 354                 if (of_find_property(np, "opp-supported-hw", NULL))
 355                         return false;
 356                 else
 357                         return true;
 358         }
 359
 360         while (count--) {
 361                 ret = of_property_read_u32_index(np, "opp-supported-hw", count,
 362                                                  &version);
 363                 if (ret) {
 364                         dev_warn(dev, "%s: failed to read opp-supported-hw property at index %d: %d\n",
 365                                  __func__, count, ret);
 366                         return false;
 367                 }
 368
 369                 /* Both of these are bitwise masks of the versions */
 370                 if (!(version & opp_table->supported_hw[count]))
 371                         return false;
 372         }
 373
 374         return true;
 375 }
 376
 377 static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,
 378                               struct opp_table *opp_table)
 379 {
 380         u32 *microvolt, *microamp = NULL;
 381         int supplies = opp_table->regulator_count, vcount, icount, ret, i, j;
 382         struct property *prop = NULL;
 383         char name[NAME_MAX];
 384
 385         /* Search for "opp-microvolt-<name>" */
 386         if (opp_table->prop_name) {
 387                 snprintf(name, sizeof(name), "opp-microvolt-%s",
 388                          opp_table->prop_name);
 389                 prop = of_find_property(opp->np, name, NULL);
 390         }
 391
 392         if (!prop) {
 393                 /* Search for "opp-microvolt" */
 394                 sprintf(name, "opp-microvolt");
 395                 prop = of_find_property(opp->np, name, NULL);
 396
 397                 /* Missing property isn't a problem, but an invalid entry is */
 398                 if (!prop) {
 399                         if (unlikely(supplies == -1)) {
 400                                 /* Initialize regulator_count */
 401                                 opp_table->regulator_count = 0;
 402                                 return 0;
 403                         }
 404
 405                         if (!supplies)
 406                                 return 0;
 407
 408                         dev_err(dev, "%s: opp-microvolt missing although OPP managing regulators\n",
 409                                 __func__);
 410                         return -EINVAL;
 411                 }
 412         }
 413
 414         if (unlikely(supplies == -1)) {
 415                 /* Initialize regulator_count */
 416                 supplies = opp_table->regulator_count = 1;
 417         } else if (unlikely(!supplies)) {
 418                 dev_err(dev, "%s: opp-microvolt wasn't expected\n", __func__);
 419                 return -EINVAL;
 420         }
 421
 422         vcount = of_property_count_u32_elems(opp->np, name);
 423         if (vcount < 0) {
 424                 dev_err(dev, "%s: Invalid %s property (%d)\n",
 425                         __func__, name, vcount);
 426                 return vcount;
 427         }
 428
 429         /* There can be one or three elements per supply */
 430         if (vcount != supplies && vcount != supplies * 3) {
 431                 dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
 432                         __func__, name, vcount, supplies);
 433                 return -EINVAL;
 434         }
 435
 436         microvolt = kmalloc_array(vcount, sizeof(*microvolt), GFP_KERNEL);
 437         if (!microvolt)
 438                 return -ENOMEM;
 439
 440         ret = of_property_read_u32_array(opp->np, name, microvolt, vcount);
 441         if (ret) {
 442                 dev_err(dev, "%s: error parsing %s: %d\n", __func__, name, ret);
 443                 ret = -EINVAL;
 444                 goto free_microvolt;
 445         }
 446
 447         /* Search for "opp-microamp-<name>" */
 448         prop = NULL;
 449         if (opp_table->prop_name) {
 450                 snprintf(name, sizeof(name), "opp-microamp-%s",
 451                          opp_table->prop_name);
 452                 prop = of_find_property(opp->np, name, NULL);
 453         }
 454
 455         if (!prop) {
 456                 /* Search for "opp-microamp" */
 457                 sprintf(name, "opp-microamp");
 458                 prop = of_find_property(opp->np, name, NULL);
 459         }
 460
 461         if (prop) {
 462                 icount = of_property_count_u32_elems(opp->np, name);
 463                 if (icount < 0) {
 464                         dev_err(dev, "%s: Invalid %s property (%d)\n", __func__,
 465                                 name, icount);
 466                         ret = icount;
 467                         goto free_microvolt;
 468                 }
 469
 470                 if (icount != supplies) {
 471                         dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
 472                                 __func__, name, icount, supplies);
 473                         ret = -EINVAL;
 474                         goto free_microvolt;
 475                 }
 476
 477                 microamp = kmalloc_array(icount, sizeof(*microamp), GFP_KERNEL);
 478                 if (!microamp) {
 479                         ret = -EINVAL;
 480                         goto free_microvolt;
 481                 }
 482
 483                 ret = of_property_read_u32_array(opp->np, name, microamp,
 484                                                  icount);
 485                 if (ret) {
 486                         dev_err(dev, "%s: error parsing %s: %d\n", __func__,
 487                                 name, ret);
 488                         ret = -EINVAL;
 489                         goto free_microamp;
 490                 }
 491         }
 492
 493         for (i = 0, j = 0; i < supplies; i++) {
 494                 opp->supplies[i].u_volt = microvolt[j++];
 495
 496                 if (vcount == supplies) {
 497                         opp->supplies[i].u_volt_min = opp->supplies[i].u_volt;
 498                         opp->supplies[i].u_volt_max = opp->supplies[i].u_volt;
 499                 } else {
 500                         opp->supplies[i].u_volt_min = microvolt[j++];
 501                         opp->supplies[i].u_volt_max = microvolt[j++];
 502                 }
 503
 504                 if (microamp)
 505                         opp->supplies[i].u_amp = microamp[i];
 506         }
 507
 508 free_microamp:
 509         kfree(microamp);
 510 free_microvolt:
 511         kfree(microvolt);
 512
 513         return ret;
 514 }
 515
 516 /**
 517  * dev_pm_opp_of_remove_table() - Free OPP table entries created from static DT
 518  *                                entries
 519  * @dev:        device pointer used to lookup OPP table.
 520  *
 521  * Free OPPs created using static entries present in DT.
 522  */
 523 void dev_pm_opp_of_remove_table(struct device *dev)
 524 {
 525         _dev_pm_opp_find_and_remove_table(dev);
 526 }
 527 EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table);
 528
 529 /**
 530  * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings)
 531  * @opp_table:  OPP table
 532  * @dev:        device for which we do this operation
 533  * @np:         device node
 534  *
 535  * This function adds an opp definition to the opp table and returns status. The
 536  * opp can be controlled using dev_pm_opp_enable/disable functions and may be
 537  * removed by dev_pm_opp_remove.
 538  *
 539  * Return:
 540  * Valid OPP pointer:
 541  *              On success
 542  * NULL:
 543  *              Duplicate OPPs (both freq and volt are same) and opp->available
 544  *              OR if the OPP is not supported by hardware.
 545  * ERR_PTR(-EEXIST):
 546  *              Freq are same and volt are different OR
 547  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 548  * ERR_PTR(-ENOMEM):
 549  *              Memory allocation failure
 550  * ERR_PTR(-EINVAL):
 551  *              Failed parsing the OPP node
 552  */
 553 static struct dev_pm_opp *_opp_add_static_v2(struct opp_table *opp_table,
 554                 struct device *dev, struct device_node *np)
 555 {
 556         struct dev_pm_opp *new_opp;
 557         u64 rate = 0;
 558         u32 val;
 559         int ret;
 560         bool rate_not_available = false;
 561
 562         new_opp = _opp_allocate(opp_table);
 563         if (!new_opp)
 564                 return ERR_PTR(-ENOMEM);
 565
 566         ret = of_property_read_u64(np, "opp-hz", &rate);
 567         if (ret < 0) {
 568                 /* "opp-hz" is optional for devices like power domains. */
 569                 if (!opp_table->is_genpd) {
 570                         dev_err(dev, "%s: opp-hz not found\n", __func__);
 571                         goto free_opp;
 572                 }
 573
 574                 rate_not_available = true;
 575         } else {
 576                 /*
 577                  * Rate is defined as an unsigned long in clk API, and so
 578                  * casting explicitly to its type. Must be fixed once rate is 64
 579                  * bit guaranteed in clk API.
 580                  */
 581                 new_opp->rate = (unsigned long)rate;
 582         }
 583
 584         of_property_read_u32(np, "opp-level", &new_opp->level);
 585
 586         /* Check if the OPP supports hardware's hierarchy of versions or not */
 587         if (!_opp_is_supported(dev, opp_table, np)) {
 588                 dev_dbg(dev, "OPP not supported by hardware: %llu\n", rate);
 589                 goto free_opp;
 590         }
 591
 592         new_opp->turbo = of_property_read_bool(np, "turbo-mode");
 593
 594         new_opp->np = np;
 595         new_opp->dynamic = false;
 596         new_opp->available = true;
 597
 598         ret = _of_opp_alloc_required_opps(opp_table, new_opp);
 599         if (ret)
 600                 goto free_opp;
 601
 602         if (!of_property_read_u32(np, "clock-latency-ns", &val))
 603                 new_opp->clock_latency_ns = val;
 604
 605         ret = opp_parse_supplies(new_opp, dev, opp_table);
 606         if (ret)
 607                 goto free_required_opps;
 608
 609         if (opp_table->is_genpd)
 610                 new_opp->pstate = pm_genpd_opp_to_performance_state(dev, new_opp);
 611
 612         ret = _opp_add(dev, new_opp, opp_table, rate_not_available);
 613         if (ret) {
 614                 /* Don't return error for duplicate OPPs */
 615                 if (ret == -EBUSY)
 616                         ret = 0;
 617                 goto free_required_opps;
 618         }
 619
 620         /* OPP to select on device suspend */
 621         if (of_property_read_bool(np, "opp-suspend")) {
 622                 if (opp_table->suspend_opp) {
 623                         dev_warn(dev, "%s: Multiple suspend OPPs found (%lu %lu)\n",
 624                                  __func__, opp_table->suspend_opp->rate,
 625                                  new_opp->rate);
 626                 } else {
 627                         new_opp->suspend = true;
 628                         opp_table->suspend_opp = new_opp;
 629                 }
 630         }
 631
 632         if (new_opp->clock_latency_ns > opp_table->clock_latency_ns_max)
 633                 opp_table->clock_latency_ns_max = new_opp->clock_latency_ns;
 634
 635         pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu\n",
 636                  __func__, new_opp->turbo, new_opp->rate,
 637                  new_opp->supplies[0].u_volt, new_opp->supplies[0].u_volt_min,
 638                  new_opp->supplies[0].u_volt_max, new_opp->clock_latency_ns);
 639
 640         /*
 641          * Notify the changes in the availability of the operable
 642          * frequency/voltage list.
 643          */
 644         blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ADD, new_opp);
 645         return new_opp;
 646
 647 free_required_opps:
 648         _of_opp_free_required_opps(opp_table, new_opp);
 649 free_opp:
 650         _opp_free(new_opp);
 651
 652         return ERR_PTR(ret);
 653 }
 654
 655 /* Initializes OPP tables based on new bindings */
 656 static int _of_add_opp_table_v2(struct device *dev, struct opp_table *opp_table)
 657 {
 658         struct device_node *np;
 659         int ret, count = 0, pstate_count = 0;
 660         struct dev_pm_opp *opp;
 661
 662         /* OPP table is already initialized for the device */
 663         if (opp_table->parsed_static_opps) {
 664                 kref_get(&opp_table->list_kref);
 665                 return 0;
 666         }
 667
 668         kref_init(&opp_table->list_kref);
 669
 670         /* We have opp-table node now, iterate over it and add OPPs */
 671         for_each_available_child_of_node(opp_table->np, np) {
 672                 opp = _opp_add_static_v2(opp_table, dev, np);
 673                 if (IS_ERR(opp)) {
 674                         ret = PTR_ERR(opp);
 675                         dev_err(dev, "%s: Failed to add OPP, %d\n", __func__,
 676                                 ret);
 677                         of_node_put(np);
 678                         goto put_list_kref;
 679                 } else if (opp) {
 680                         count++;
 681                 }
 682         }
 683
 684         /* There should be one of more OPP defined */
 685         if (WARN_ON(!count)) {
 686                 ret = -ENOENT;
 687                 goto put_list_kref;
 688         }
 689
 690         list_for_each_entry(opp, &opp_table->opp_list, node)
 691                 pstate_count += !!opp->pstate;
 692
 693         /* Either all or none of the nodes shall have performance state set */
 694         if (pstate_count && pstate_count != count) {
 695                 dev_err(dev, "Not all nodes have performance state set (%d: %d)\n",
 696                         count, pstate_count);
 697                 ret = -ENOENT;
 698                 goto put_list_kref;
 699         }
 700
 701         if (pstate_count)
 702                 opp_table->genpd_performance_state = true;
 703
 704         opp_table->parsed_static_opps = true;
 705
 706         return 0;
 707
 708 put_list_kref:
 709         _put_opp_list_kref(opp_table);
 710
 711         return ret;
 712 }
 713
 714 /* Initializes OPP tables based on old-deprecated bindings */
 715 static int _of_add_opp_table_v1(struct device *dev, struct opp_table *opp_table)
 716 {
 717         const struct property *prop;
 718         const __be32 *val;
 719         int nr, ret = 0;
 720
 721         prop = of_find_property(dev->of_node, "operating-points", NULL);
 722         if (!prop)
 723                 return -ENODEV;
 724         if (!prop->value)
 725                 return -ENODATA;
 726
 727         /*
 728          * Each OPP is a set of tuples consisting of frequency and
 729          * voltage like <freq-kHz vol-uV>.
 730          */
 731         nr = prop->length / sizeof(u32);
 732         if (nr % 2) {
 733                 dev_err(dev, "%s: Invalid OPP table\n", __func__);
 734                 return -EINVAL;
 735         }
 736
 737         kref_init(&opp_table->list_kref);
 738
 739         val = prop->value;
 740         while (nr) {
 741                 unsigned long freq = be32_to_cpup(val++) * 1000;
 742                 unsigned long volt = be32_to_cpup(val++);
 743
 744                 ret = _opp_add_v1(opp_table, dev, freq, volt, false);
 745                 if (ret) {
 746                         dev_err(dev, "%s: Failed to add OPP %ld (%d)\n",
 747                                 __func__, freq, ret);
 748                         _put_opp_list_kref(opp_table);
 749                         return ret;
 750                 }
 751                 nr -= 2;
 752         }
 753
 754         return ret;
 755 }
 756
 757 /**
 758  * dev_pm_opp_of_add_table() - Initialize opp table from device tree
 759  * @dev:        device pointer used to lookup OPP table.
 760  *
 761  * Register the initial OPP table with the OPP library for given device.
 762  *
 763  * Return:
 764  * 0            On success OR
 765  *              Duplicate OPPs (both freq and volt are same) and opp->available
 766  * -EEXIST      Freq are same and volt are different OR
 767  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 768  * -ENOMEM      Memory allocation failure
 769  * -ENODEV      when 'operating-points' property is not found or is invalid data
 770  *              in device node.
 771  * -ENODATA     when empty 'operating-points' property is found
 772  * -EINVAL      when invalid entries are found in opp-v2 table
 773  */
 774 int dev_pm_opp_of_add_table(struct device *dev)
 775 {
 776         struct opp_table *opp_table;
 777         int ret;
 778
 779         opp_table = dev_pm_opp_get_opp_table_indexed(dev, 0);
 780         if (!opp_table)
 781                 return -ENOMEM;
 782
 783         /*
 784          * OPPs have two version of bindings now. Also try the old (v1)
 785          * bindings for backward compatibility with older dtbs.
 786          */
 787         if (opp_table->np)
 788                 ret = _of_add_opp_table_v2(dev, opp_table);
 789         else
 790                 ret = _of_add_opp_table_v1(dev, opp_table);
 791
 792         if (ret)
 793                 dev_pm_opp_put_opp_table(opp_table);
 794
 795         return ret;
 796 }
 797 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table);
 798
 799 /**
 800  * dev_pm_opp_of_add_table_indexed() - Initialize indexed opp table from device tree
 801  * @dev:        device pointer used to lookup OPP table.
 802  * @index:      Index number.
 803  *
 804  * Register the initial OPP table with the OPP library for given device only
 805  * using the "operating-points-v2" property.
 806  *
 807  * Return:
 808  * 0            On success OR
 809  *              Duplicate OPPs (both freq and volt are same) and opp->available
 810  * -EEXIST      Freq are same and volt are different OR
 811  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 812  * -ENOMEM      Memory allocation failure
 813  * -ENODEV      when 'operating-points' property is not found or is invalid data
 814  *              in device node.
 815  * -ENODATA     when empty 'operating-points' property is found
 816  * -EINVAL      when invalid entries are found in opp-v2 table
 817  */
 818 int dev_pm_opp_of_add_table_indexed(struct device *dev, int index)
 819 {
 820         struct opp_table *opp_table;
 821         int ret, count;
 822
 823         if (index) {
 824                 /*
 825                  * If only one phandle is present, then the same OPP table
 826                  * applies for all index requests.
 827                  */
 828                 count = of_count_phandle_with_args(dev->of_node,
 829                                                    "operating-points-v2", NULL);
 830                 if (count == 1)
 831                         index = 0;
 832         }
 833
 834         opp_table = dev_pm_opp_get_opp_table_indexed(dev, index);
 835         if (!opp_table)
 836                 return -ENOMEM;
 837
 838         ret = _of_add_opp_table_v2(dev, opp_table);
 839         if (ret)
 840                 dev_pm_opp_put_opp_table(opp_table);
 841
 842         return ret;
 843 }
 844 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table_indexed);
 845
 846 /* CPU device specific helpers */
 847
 848 /**
 849  * dev_pm_opp_of_cpumask_remove_table() - Removes OPP table for @cpumask
 850  * @cpumask:    cpumask for which OPP table needs to be removed
 851  *
 852  * This removes the OPP tables for CPUs present in the @cpumask.
 853  * This should be used only to remove static entries created from DT.
 854  */
 855 void dev_pm_opp_of_cpumask_remove_table(const struct cpumask *cpumask)
 856 {
 857         _dev_pm_opp_cpumask_remove_table(cpumask, -1);
 858 }
 859 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_remove_table);
 860
 861 /**
 862  * dev_pm_opp_of_cpumask_add_table() - Adds OPP table for @cpumask
 863  * @cpumask:    cpumask for which OPP table needs to be added.
 864  *
 865  * This adds the OPP tables for CPUs present in the @cpumask.
 866  */
 867 int dev_pm_opp_of_cpumask_add_table(const struct cpumask *cpumask)
 868 {
 869         struct device *cpu_dev;
 870         int cpu, ret;
 871
 872         if (WARN_ON(cpumask_empty(cpumask)))
 873                 return -ENODEV;
 874
 875         for_each_cpu(cpu, cpumask) {
 876                 cpu_dev = get_cpu_device(cpu);
 877                 if (!cpu_dev) {
 878                         pr_err("%s: failed to get cpu%d device\n", __func__,
 879                                cpu);
 880                         ret = -ENODEV;
 881                         goto remove_table;
 882                 }
 883
 884                 ret = dev_pm_opp_of_add_table(cpu_dev);
 885                 if (ret) {
 886                         /*
 887                          * OPP may get registered dynamically, don't print error
 888                          * message here.
 889                          */
 890                         pr_debug("%s: couldn't find opp table for cpu:%d, %d\n",
 891                                  __func__, cpu, ret);
 892
 893                         goto remove_table;
 894                 }
 895         }
 896
 897         return 0;
 898
 899 remove_table:
 900         /* Free all other OPPs */
 901         _dev_pm_opp_cpumask_remove_table(cpumask, cpu);
 902
 903         return ret;
 904 }
 905 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_add_table);
 906
 907 /*
 908  * Works only for OPP v2 bindings.
 909  *
 910  * Returns -ENOENT if operating-points-v2 bindings aren't supported.
 911  */
 912 /**
 913  * dev_pm_opp_of_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with
 914  *                                    @cpu_dev using operating-points-v2
 915  *                                    bindings.
 916  *
 917  * @cpu_dev:    CPU device for which we do this operation
 918  * @cpumask:    cpumask to update with information of sharing CPUs
 919  *
 920  * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev.
 921  *
 922  * Returns -ENOENT if operating-points-v2 isn't present for @cpu_dev.
 923  */
 924 int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev,
 925                                    struct cpumask *cpumask)
 926 {
 927         struct device_node *np, *tmp_np, *cpu_np;
 928         int cpu, ret = 0;
 929
 930         /* Get OPP descriptor node */
 931         np = dev_pm_opp_of_get_opp_desc_node(cpu_dev);
 932         if (!np) {
 933                 dev_dbg(cpu_dev, "%s: Couldn't find opp node.\n", __func__);
 934                 return -ENOENT;
 935         }
 936
 937         cpumask_set_cpu(cpu_dev->id, cpumask);
 938
 939         /* OPPs are shared ? */
 940         if (!of_property_read_bool(np, "opp-shared"))
 941                 goto put_cpu_node;
 942
 943         for_each_possible_cpu(cpu) {
 944                 if (cpu == cpu_dev->id)
 945                         continue;
 946
 947                 cpu_np = of_cpu_device_node_get(cpu);
 948                 if (!cpu_np) {
 949                         dev_err(cpu_dev, "%s: failed to get cpu%d node\n",
 950                                 __func__, cpu);
 951                         ret = -ENOENT;
 952                         goto put_cpu_node;
 953                 }
 954
 955                 /* Get OPP descriptor node */
 956                 tmp_np = _opp_of_get_opp_desc_node(cpu_np, 0);
 957                 of_node_put(cpu_np);
 958                 if (!tmp_np) {
 959                         pr_err("%pOF: Couldn't find opp node\n", cpu_np);
 960                         ret = -ENOENT;
 961                         goto put_cpu_node;
 962                 }
 963
 964                 /* CPUs are sharing opp node */
 965                 if (np == tmp_np)
 966                         cpumask_set_cpu(cpu, cpumask);
 967
 968                 of_node_put(tmp_np);
 969         }
 970
 971 put_cpu_node:
 972         of_node_put(np);
 973         return ret;
 974 }
 975 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus);
 976
 977 /**
 978  * of_get_required_opp_performance_state() - Search for required OPP and return its performance state.
 979  * @np: Node that contains the "required-opps" property.
 980  * @index: Index of the phandle to parse.
 981  *
 982  * Returns the performance state of the OPP pointed out by the "required-opps"
 983  * property at @index in @np.
 984  *
 985  * Return: Zero or positive performance state on success, otherwise negative
 986  * value on errors.
 987  */
 988 int of_get_required_opp_performance_state(struct device_node *np, int index)
 989 {
 990         struct dev_pm_opp *opp;
 991         struct device_node *required_np;
 992         struct opp_table *opp_table;
 993         int pstate = -EINVAL;
 994
 995         required_np = of_parse_required_opp(np, index);
 996         if (!required_np)
 997                 return -EINVAL;
 998
 999         opp_table = _find_table_of_opp_np(required_np);
1000         if (IS_ERR(opp_table)) {
1001                 pr_err("%s: Failed to find required OPP table %pOF: %ld\n",
1002                        __func__, np, PTR_ERR(opp_table));
1003                 goto put_required_np;
1004         }
1005
1006         opp = _find_opp_of_np(opp_table, required_np);
1007         if (opp) {
1008                 pstate = opp->pstate;
1009                 dev_pm_opp_put(opp);
1010         }
1011
1012         dev_pm_opp_put_opp_table(opp_table);
1013
1014 put_required_np:
1015         of_node_put(required_np);
1016
1017         return pstate;
1018 }
1019 EXPORT_SYMBOL_GPL(of_get_required_opp_performance_state);
1020
1021 /**
1022  * dev_pm_opp_get_of_node() - Gets the DT node corresponding to an opp
1023  * @opp:        opp for which DT node has to be returned for
1024  *
1025  * Return: DT node corresponding to the opp, else 0 on success.
1026  *
1027  * The caller needs to put the node with of_node_put() after using it.
1028  */
1029 struct device_node *dev_pm_opp_get_of_node(struct dev_pm_opp *opp)
1030 {
1031         if (IS_ERR_OR_NULL(opp)) {
1032                 pr_err("%s: Invalid parameters\n", __func__);
1033                 return NULL;
1034         }
1035
1036         return of_node_get(opp->np);
1037 }
1038 EXPORT_SYMBOL_GPL(dev_pm_opp_get_of_node);
1039
1040 /*
1041  * Callback function provided to the Energy Model framework upon registration.
1042  * This computes the power estimated by @CPU at @kHz if it is the frequency
1043  * of an existing OPP, or at the frequency of the first OPP above @kHz otherwise
1044  * (see dev_pm_opp_find_freq_ceil()). This function updates @kHz to the ceiled
1045  * frequency and @mW to the associated power. The power is estimated as
1046  * P = C * V^2 * f with C being the CPU's capacitance and V and f respectively
1047  * the voltage and frequency of the OPP.
1048  *
1049  * Returns -ENODEV if the CPU device cannot be found, -EINVAL if the power
1050  * calculation failed because of missing parameters, 0 otherwise.
1051  */
1052 static int __maybe_unused _get_cpu_power(unsigned long *mW, unsigned long *kHz,
1053                                          int cpu)
1054 {
1055         struct device *cpu_dev;
1056         struct dev_pm_opp *opp;
1057         struct device_node *np;
1058         unsigned long mV, Hz;
1059         u32 cap;
1060         u64 tmp;
1061         int ret;
1062
1063         cpu_dev = get_cpu_device(cpu);
1064         if (!cpu_dev)
1065                 return -ENODEV;
1066
1067         np = of_node_get(cpu_dev->of_node);
1068         if (!np)
1069                 return -EINVAL;
1070
1071         ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1072         of_node_put(np);
1073         if (ret)
1074                 return -EINVAL;
1075
1076         Hz = *kHz * 1000;
1077         opp = dev_pm_opp_find_freq_ceil(cpu_dev, &Hz);
1078         if (IS_ERR(opp))
1079                 return -EINVAL;
1080
1081         mV = dev_pm_opp_get_voltage(opp) / 1000;
1082         dev_pm_opp_put(opp);
1083         if (!mV)
1084                 return -EINVAL;
1085
1086         tmp = (u64)cap * mV * mV * (Hz / 1000000);
1087         do_div(tmp, 1000000000);
1088
1089         *mW = (unsigned long)tmp;
1090         *kHz = Hz / 1000;
1091
1092         return 0;
1093 }
1094
1095 /**
1096  * dev_pm_opp_of_register_em() - Attempt to register an Energy Model
1097  * @cpus        : CPUs for which an Energy Model has to be registered
1098  *
1099  * This checks whether the "dynamic-power-coefficient" devicetree property has
1100  * been specified, and tries to register an Energy Model with it if it has.
1101  */
1102 void dev_pm_opp_of_register_em(struct cpumask *cpus)
1103 {
1104         struct em_data_callback em_cb = EM_DATA_CB(_get_cpu_power);
1105         int ret, nr_opp, cpu = cpumask_first(cpus);
1106         struct device *cpu_dev;
1107         struct device_node *np;
1108         u32 cap;
1109
1110         cpu_dev = get_cpu_device(cpu);
1111         if (!cpu_dev)
1112                 return;
1113
1114         nr_opp = dev_pm_opp_get_opp_count(cpu_dev);
1115         if (nr_opp <= 0)
1116                 return;
1117
1118         np = of_node_get(cpu_dev->of_node);
1119         if (!np)
1120                 return;
1121
1122         /*
1123          * Register an EM only if the 'dynamic-power-coefficient' property is
1124          * set in devicetree. It is assumed the voltage values are known if that
1125          * property is set since it is useless otherwise. If voltages are not
1126          * known, just let the EM registration fail with an error to alert the
1127          * user about the inconsistent configuration.
1128          */
1129         ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1130         of_node_put(np);
1131         if (ret || !cap)
1132                 return;
1133
1134         em_register_perf_domain(cpus, nr_opp, &em_cb);
1135 }
1136 EXPORT_SYMBOL_GPL(dev_pm_opp_of_register_em);