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         struct device **genpd_virt_devs = opp_table->genpd_virt_devs;
 145         int i;
 146
 147         if (!required_opp_tables)
 148                 return;
 149
 150         for (i = 0; i < opp_table->required_opp_count; i++) {
 151                 if (IS_ERR_OR_NULL(required_opp_tables[i]))
 152                         break;
 153
 154                 dev_pm_opp_put_opp_table(required_opp_tables[i]);
 155         }
 156
 157         kfree(required_opp_tables);
 158         kfree(genpd_virt_devs);
 159
 160         opp_table->required_opp_count = 0;
 161         opp_table->genpd_virt_devs = NULL;
 162         opp_table->required_opp_tables = NULL;
 163 }
 164
 165 /*
 166  * Populate all devices and opp tables which are part of "required-opps" list.
 167  * Checking only the first OPP node should be enough.
 168  */
 169 static void _opp_table_alloc_required_tables(struct opp_table *opp_table,
 170                                              struct device *dev,
 171                                              struct device_node *opp_np)
 172 {
 173         struct opp_table **required_opp_tables;
 174         struct device **genpd_virt_devs = NULL;
 175         struct device_node *required_np, *np;
 176         int count, i;
 177
 178         /* Traversing the first OPP node is all we need */
 179         np = of_get_next_available_child(opp_np, NULL);
 180         if (!np) {
 181                 dev_err(dev, "Empty OPP table\n");
 182                 return;
 183         }
 184
 185         count = of_count_phandle_with_args(np, "required-opps", NULL);
 186         if (!count)
 187                 goto put_np;
 188
 189         if (count > 1) {
 190                 genpd_virt_devs = kcalloc(count, sizeof(*genpd_virt_devs),
 191                                         GFP_KERNEL);
 192                 if (!genpd_virt_devs)
 193                         goto put_np;
 194         }
 195
 196         required_opp_tables = kcalloc(count, sizeof(*required_opp_tables),
 197                                       GFP_KERNEL);
 198         if (!required_opp_tables) {
 199                 kfree(genpd_virt_devs);
 200                 goto put_np;
 201         }
 202
 203         opp_table->genpd_virt_devs = genpd_virt_devs;
 204         opp_table->required_opp_tables = required_opp_tables;
 205         opp_table->required_opp_count = count;
 206
 207         for (i = 0; i < count; i++) {
 208                 required_np = of_parse_required_opp(np, i);
 209                 if (!required_np)
 210                         goto free_required_tables;
 211
 212                 required_opp_tables[i] = _find_table_of_opp_np(required_np);
 213                 of_node_put(required_np);
 214
 215                 if (IS_ERR(required_opp_tables[i]))
 216                         goto free_required_tables;
 217
 218                 /*
 219                  * We only support genpd's OPPs in the "required-opps" for now,
 220                  * as we don't know how much about other cases. Error out if the
 221                  * required OPP doesn't belong to a genpd.
 222                  */
 223                 if (!required_opp_tables[i]->is_genpd) {
 224                         dev_err(dev, "required-opp doesn't belong to genpd: %pOF\n",
 225                                 required_np);
 226                         goto free_required_tables;
 227                 }
 228         }
 229
 230         goto put_np;
 231
 232 free_required_tables:
 233         _opp_table_free_required_tables(opp_table);
 234 put_np:
 235         of_node_put(np);
 236 }
 237
 238 void _of_init_opp_table(struct opp_table *opp_table, struct device *dev,
 239                         int index)
 240 {
 241         struct device_node *np, *opp_np;
 242         u32 val;
 243
 244         /*
 245          * Only required for backward compatibility with v1 bindings, but isn't
 246          * harmful for other cases. And so we do it unconditionally.
 247          */
 248         np = of_node_get(dev->of_node);
 249         if (!np)
 250                 return;
 251
 252         if (!of_property_read_u32(np, "clock-latency", &val))
 253                 opp_table->clock_latency_ns_max = val;
 254         of_property_read_u32(np, "voltage-tolerance",
 255                              &opp_table->voltage_tolerance_v1);
 256
 257         if (of_find_property(np, "#power-domain-cells", NULL))
 258                 opp_table->is_genpd = true;
 259
 260         /* Get OPP table node */
 261         opp_np = _opp_of_get_opp_desc_node(np, index);
 262         of_node_put(np);
 263
 264         if (!opp_np)
 265                 return;
 266
 267         if (of_property_read_bool(opp_np, "opp-shared"))
 268                 opp_table->shared_opp = OPP_TABLE_ACCESS_SHARED;
 269         else
 270                 opp_table->shared_opp = OPP_TABLE_ACCESS_EXCLUSIVE;
 271
 272         opp_table->np = opp_np;
 273
 274         _opp_table_alloc_required_tables(opp_table, dev, opp_np);
 275         of_node_put(opp_np);
 276 }
 277
 278 void _of_clear_opp_table(struct opp_table *opp_table)
 279 {
 280         _opp_table_free_required_tables(opp_table);
 281 }
 282
 283 /*
 284  * Release all resources previously acquired with a call to
 285  * _of_opp_alloc_required_opps().
 286  */
 287 void _of_opp_free_required_opps(struct opp_table *opp_table,
 288                                 struct dev_pm_opp *opp)
 289 {
 290         struct dev_pm_opp **required_opps = opp->required_opps;
 291         int i;
 292
 293         if (!required_opps)
 294                 return;
 295
 296         for (i = 0; i < opp_table->required_opp_count; i++) {
 297                 if (!required_opps[i])
 298                         break;
 299
 300                 /* Put the reference back */
 301                 dev_pm_opp_put(required_opps[i]);
 302         }
 303
 304         kfree(required_opps);
 305         opp->required_opps = NULL;
 306 }
 307
 308 /* Populate all required OPPs which are part of "required-opps" list */
 309 static int _of_opp_alloc_required_opps(struct opp_table *opp_table,
 310                                        struct dev_pm_opp *opp)
 311 {
 312         struct dev_pm_opp **required_opps;
 313         struct opp_table *required_table;
 314         struct device_node *np;
 315         int i, ret, count = opp_table->required_opp_count;
 316
 317         if (!count)
 318                 return 0;
 319
 320         required_opps = kcalloc(count, sizeof(*required_opps), GFP_KERNEL);
 321         if (!required_opps)
 322                 return -ENOMEM;
 323
 324         opp->required_opps = required_opps;
 325
 326         for (i = 0; i < count; i++) {
 327                 required_table = opp_table->required_opp_tables[i];
 328
 329                 np = of_parse_required_opp(opp->np, i);
 330                 if (unlikely(!np)) {
 331                         ret = -ENODEV;
 332                         goto free_required_opps;
 333                 }
 334
 335                 required_opps[i] = _find_opp_of_np(required_table, np);
 336                 of_node_put(np);
 337
 338                 if (!required_opps[i]) {
 339                         pr_err("%s: Unable to find required OPP node: %pOF (%d)\n",
 340                                __func__, opp->np, i);
 341                         ret = -ENODEV;
 342                         goto free_required_opps;
 343                 }
 344         }
 345
 346         return 0;
 347
 348 free_required_opps:
 349         _of_opp_free_required_opps(opp_table, opp);
 350
 351         return ret;
 352 }
 353
 354 static bool _opp_is_supported(struct device *dev, struct opp_table *opp_table,
 355                               struct device_node *np)
 356 {
 357         unsigned int count = opp_table->supported_hw_count;
 358         u32 version;
 359         int ret;
 360
 361         if (!opp_table->supported_hw) {
 362                 /*
 363                  * In the case that no supported_hw has been set by the
 364                  * platform but there is an opp-supported-hw value set for
 365                  * an OPP then the OPP should not be enabled as there is
 366                  * no way to see if the hardware supports it.
 367                  */
 368                 if (of_find_property(np, "opp-supported-hw", NULL))
 369                         return false;
 370                 else
 371                         return true;
 372         }
 373
 374         while (count--) {
 375                 ret = of_property_read_u32_index(np, "opp-supported-hw", count,
 376                                                  &version);
 377                 if (ret) {
 378                         dev_warn(dev, "%s: failed to read opp-supported-hw property at index %d: %d\n",
 379                                  __func__, count, ret);
 380                         return false;
 381                 }
 382
 383                 /* Both of these are bitwise masks of the versions */
 384                 if (!(version & opp_table->supported_hw[count]))
 385                         return false;
 386         }
 387
 388         return true;
 389 }
 390
 391 static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,
 392                               struct opp_table *opp_table)
 393 {
 394         u32 *microvolt, *microamp = NULL;
 395         int supplies = opp_table->regulator_count, vcount, icount, ret, i, j;
 396         struct property *prop = NULL;
 397         char name[NAME_MAX];
 398
 399         /* Search for "opp-microvolt-<name>" */
 400         if (opp_table->prop_name) {
 401                 snprintf(name, sizeof(name), "opp-microvolt-%s",
 402                          opp_table->prop_name);
 403                 prop = of_find_property(opp->np, name, NULL);
 404         }
 405
 406         if (!prop) {
 407                 /* Search for "opp-microvolt" */
 408                 sprintf(name, "opp-microvolt");
 409                 prop = of_find_property(opp->np, name, NULL);
 410
 411                 /* Missing property isn't a problem, but an invalid entry is */
 412                 if (!prop) {
 413                         if (unlikely(supplies == -1)) {
 414                                 /* Initialize regulator_count */
 415                                 opp_table->regulator_count = 0;
 416                                 return 0;
 417                         }
 418
 419                         if (!supplies)
 420                                 return 0;
 421
 422                         dev_err(dev, "%s: opp-microvolt missing although OPP managing regulators\n",
 423                                 __func__);
 424                         return -EINVAL;
 425                 }
 426         }
 427
 428         if (unlikely(supplies == -1)) {
 429                 /* Initialize regulator_count */
 430                 supplies = opp_table->regulator_count = 1;
 431         } else if (unlikely(!supplies)) {
 432                 dev_err(dev, "%s: opp-microvolt wasn't expected\n", __func__);
 433                 return -EINVAL;
 434         }
 435
 436         vcount = of_property_count_u32_elems(opp->np, name);
 437         if (vcount < 0) {
 438                 dev_err(dev, "%s: Invalid %s property (%d)\n",
 439                         __func__, name, vcount);
 440                 return vcount;
 441         }
 442
 443         /* There can be one or three elements per supply */
 444         if (vcount != supplies && vcount != supplies * 3) {
 445                 dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
 446                         __func__, name, vcount, supplies);
 447                 return -EINVAL;
 448         }
 449
 450         microvolt = kmalloc_array(vcount, sizeof(*microvolt), GFP_KERNEL);
 451         if (!microvolt)
 452                 return -ENOMEM;
 453
 454         ret = of_property_read_u32_array(opp->np, name, microvolt, vcount);
 455         if (ret) {
 456                 dev_err(dev, "%s: error parsing %s: %d\n", __func__, name, ret);
 457                 ret = -EINVAL;
 458                 goto free_microvolt;
 459         }
 460
 461         /* Search for "opp-microamp-<name>" */
 462         prop = NULL;
 463         if (opp_table->prop_name) {
 464                 snprintf(name, sizeof(name), "opp-microamp-%s",
 465                          opp_table->prop_name);
 466                 prop = of_find_property(opp->np, name, NULL);
 467         }
 468
 469         if (!prop) {
 470                 /* Search for "opp-microamp" */
 471                 sprintf(name, "opp-microamp");
 472                 prop = of_find_property(opp->np, name, NULL);
 473         }
 474
 475         if (prop) {
 476                 icount = of_property_count_u32_elems(opp->np, name);
 477                 if (icount < 0) {
 478                         dev_err(dev, "%s: Invalid %s property (%d)\n", __func__,
 479                                 name, icount);
 480                         ret = icount;
 481                         goto free_microvolt;
 482                 }
 483
 484                 if (icount != supplies) {
 485                         dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
 486                                 __func__, name, icount, supplies);
 487                         ret = -EINVAL;
 488                         goto free_microvolt;
 489                 }
 490
 491                 microamp = kmalloc_array(icount, sizeof(*microamp), GFP_KERNEL);
 492                 if (!microamp) {
 493                         ret = -EINVAL;
 494                         goto free_microvolt;
 495                 }
 496
 497                 ret = of_property_read_u32_array(opp->np, name, microamp,
 498                                                  icount);
 499                 if (ret) {
 500                         dev_err(dev, "%s: error parsing %s: %d\n", __func__,
 501                                 name, ret);
 502                         ret = -EINVAL;
 503                         goto free_microamp;
 504                 }
 505         }
 506
 507         for (i = 0, j = 0; i < supplies; i++) {
 508                 opp->supplies[i].u_volt = microvolt[j++];
 509
 510                 if (vcount == supplies) {
 511                         opp->supplies[i].u_volt_min = opp->supplies[i].u_volt;
 512                         opp->supplies[i].u_volt_max = opp->supplies[i].u_volt;
 513                 } else {
 514                         opp->supplies[i].u_volt_min = microvolt[j++];
 515                         opp->supplies[i].u_volt_max = microvolt[j++];
 516                 }
 517
 518                 if (microamp)
 519                         opp->supplies[i].u_amp = microamp[i];
 520         }
 521
 522 free_microamp:
 523         kfree(microamp);
 524 free_microvolt:
 525         kfree(microvolt);
 526
 527         return ret;
 528 }
 529
 530 /**
 531  * dev_pm_opp_of_remove_table() - Free OPP table entries created from static DT
 532  *                                entries
 533  * @dev:        device pointer used to lookup OPP table.
 534  *
 535  * Free OPPs created using static entries present in DT.
 536  */
 537 void dev_pm_opp_of_remove_table(struct device *dev)
 538 {
 539         _dev_pm_opp_find_and_remove_table(dev);
 540 }
 541 EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table);
 542
 543 /**
 544  * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings)
 545  * @opp_table:  OPP table
 546  * @dev:        device for which we do this operation
 547  * @np:         device node
 548  *
 549  * This function adds an opp definition to the opp table and returns status. The
 550  * opp can be controlled using dev_pm_opp_enable/disable functions and may be
 551  * removed by dev_pm_opp_remove.
 552  *
 553  * Return:
 554  * Valid OPP pointer:
 555  *              On success
 556  * NULL:
 557  *              Duplicate OPPs (both freq and volt are same) and opp->available
 558  *              OR if the OPP is not supported by hardware.
 559  * ERR_PTR(-EEXIST):
 560  *              Freq are same and volt are different OR
 561  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 562  * ERR_PTR(-ENOMEM):
 563  *              Memory allocation failure
 564  * ERR_PTR(-EINVAL):
 565  *              Failed parsing the OPP node
 566  */
 567 static struct dev_pm_opp *_opp_add_static_v2(struct opp_table *opp_table,
 568                 struct device *dev, struct device_node *np)
 569 {
 570         struct dev_pm_opp *new_opp;
 571         u64 rate = 0;
 572         u32 val;
 573         int ret;
 574         bool rate_not_available = false;
 575
 576         new_opp = _opp_allocate(opp_table);
 577         if (!new_opp)
 578                 return ERR_PTR(-ENOMEM);
 579
 580         ret = of_property_read_u64(np, "opp-hz", &rate);
 581         if (ret < 0) {
 582                 /* "opp-hz" is optional for devices like power domains. */
 583                 if (!opp_table->is_genpd) {
 584                         dev_err(dev, "%s: opp-hz not found\n", __func__);
 585                         goto free_opp;
 586                 }
 587
 588                 rate_not_available = true;
 589         } else {
 590                 /*
 591                  * Rate is defined as an unsigned long in clk API, and so
 592                  * casting explicitly to its type. Must be fixed once rate is 64
 593                  * bit guaranteed in clk API.
 594                  */
 595                 new_opp->rate = (unsigned long)rate;
 596         }
 597
 598         of_property_read_u32(np, "opp-level", &new_opp->level);
 599
 600         /* Check if the OPP supports hardware's hierarchy of versions or not */
 601         if (!_opp_is_supported(dev, opp_table, np)) {
 602                 dev_dbg(dev, "OPP not supported by hardware: %llu\n", rate);
 603                 goto free_opp;
 604         }
 605
 606         new_opp->turbo = of_property_read_bool(np, "turbo-mode");
 607
 608         new_opp->np = np;
 609         new_opp->dynamic = false;
 610         new_opp->available = true;
 611
 612         ret = _of_opp_alloc_required_opps(opp_table, new_opp);
 613         if (ret)
 614                 goto free_opp;
 615
 616         if (!of_property_read_u32(np, "clock-latency-ns", &val))
 617                 new_opp->clock_latency_ns = val;
 618
 619         ret = opp_parse_supplies(new_opp, dev, opp_table);
 620         if (ret)
 621                 goto free_required_opps;
 622
 623         if (opp_table->is_genpd)
 624                 new_opp->pstate = pm_genpd_opp_to_performance_state(dev, new_opp);
 625
 626         ret = _opp_add(dev, new_opp, opp_table, rate_not_available);
 627         if (ret) {
 628                 /* Don't return error for duplicate OPPs */
 629                 if (ret == -EBUSY)
 630                         ret = 0;
 631                 goto free_required_opps;
 632         }
 633
 634         /* OPP to select on device suspend */
 635         if (of_property_read_bool(np, "opp-suspend")) {
 636                 if (opp_table->suspend_opp) {
 637                         dev_warn(dev, "%s: Multiple suspend OPPs found (%lu %lu)\n",
 638                                  __func__, opp_table->suspend_opp->rate,
 639                                  new_opp->rate);
 640                 } else {
 641                         new_opp->suspend = true;
 642                         opp_table->suspend_opp = new_opp;
 643                 }
 644         }
 645
 646         if (new_opp->clock_latency_ns > opp_table->clock_latency_ns_max)
 647                 opp_table->clock_latency_ns_max = new_opp->clock_latency_ns;
 648
 649         pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu\n",
 650                  __func__, new_opp->turbo, new_opp->rate,
 651                  new_opp->supplies[0].u_volt, new_opp->supplies[0].u_volt_min,
 652                  new_opp->supplies[0].u_volt_max, new_opp->clock_latency_ns);
 653
 654         /*
 655          * Notify the changes in the availability of the operable
 656          * frequency/voltage list.
 657          */
 658         blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ADD, new_opp);
 659         return new_opp;
 660
 661 free_required_opps:
 662         _of_opp_free_required_opps(opp_table, new_opp);
 663 free_opp:
 664         _opp_free(new_opp);
 665
 666         return ERR_PTR(ret);
 667 }
 668
 669 /* Initializes OPP tables based on new bindings */
 670 static int _of_add_opp_table_v2(struct device *dev, struct opp_table *opp_table)
 671 {
 672         struct device_node *np;
 673         int ret, count = 0, pstate_count = 0;
 674         struct dev_pm_opp *opp;
 675
 676         /* OPP table is already initialized for the device */
 677         if (opp_table->parsed_static_opps) {
 678                 kref_get(&opp_table->list_kref);
 679                 return 0;
 680         }
 681
 682         kref_init(&opp_table->list_kref);
 683
 684         /* We have opp-table node now, iterate over it and add OPPs */
 685         for_each_available_child_of_node(opp_table->np, np) {
 686                 opp = _opp_add_static_v2(opp_table, dev, np);
 687                 if (IS_ERR(opp)) {
 688                         ret = PTR_ERR(opp);
 689                         dev_err(dev, "%s: Failed to add OPP, %d\n", __func__,
 690                                 ret);
 691                         of_node_put(np);
 692                         goto put_list_kref;
 693                 } else if (opp) {
 694                         count++;
 695                 }
 696         }
 697
 698         /* There should be one of more OPP defined */
 699         if (WARN_ON(!count)) {
 700                 ret = -ENOENT;
 701                 goto put_list_kref;
 702         }
 703
 704         list_for_each_entry(opp, &opp_table->opp_list, node)
 705                 pstate_count += !!opp->pstate;
 706
 707         /* Either all or none of the nodes shall have performance state set */
 708         if (pstate_count && pstate_count != count) {
 709                 dev_err(dev, "Not all nodes have performance state set (%d: %d)\n",
 710                         count, pstate_count);
 711                 ret = -ENOENT;
 712                 goto put_list_kref;
 713         }
 714
 715         if (pstate_count)
 716                 opp_table->genpd_performance_state = true;
 717
 718         opp_table->parsed_static_opps = true;
 719
 720         return 0;
 721
 722 put_list_kref:
 723         _put_opp_list_kref(opp_table);
 724
 725         return ret;
 726 }
 727
 728 /* Initializes OPP tables based on old-deprecated bindings */
 729 static int _of_add_opp_table_v1(struct device *dev, struct opp_table *opp_table)
 730 {
 731         const struct property *prop;
 732         const __be32 *val;
 733         int nr, ret = 0;
 734
 735         prop = of_find_property(dev->of_node, "operating-points", NULL);
 736         if (!prop)
 737                 return -ENODEV;
 738         if (!prop->value)
 739                 return -ENODATA;
 740
 741         /*
 742          * Each OPP is a set of tuples consisting of frequency and
 743          * voltage like <freq-kHz vol-uV>.
 744          */
 745         nr = prop->length / sizeof(u32);
 746         if (nr % 2) {
 747                 dev_err(dev, "%s: Invalid OPP table\n", __func__);
 748                 return -EINVAL;
 749         }
 750
 751         kref_init(&opp_table->list_kref);
 752
 753         val = prop->value;
 754         while (nr) {
 755                 unsigned long freq = be32_to_cpup(val++) * 1000;
 756                 unsigned long volt = be32_to_cpup(val++);
 757
 758                 ret = _opp_add_v1(opp_table, dev, freq, volt, false);
 759                 if (ret) {
 760                         dev_err(dev, "%s: Failed to add OPP %ld (%d)\n",
 761                                 __func__, freq, ret);
 762                         _put_opp_list_kref(opp_table);
 763                         return ret;
 764                 }
 765                 nr -= 2;
 766         }
 767
 768         return ret;
 769 }
 770
 771 /**
 772  * dev_pm_opp_of_add_table() - Initialize opp table from device tree
 773  * @dev:        device pointer used to lookup OPP table.
 774  *
 775  * Register the initial OPP table with the OPP library for given device.
 776  *
 777  * Return:
 778  * 0            On success OR
 779  *              Duplicate OPPs (both freq and volt are same) and opp->available
 780  * -EEXIST      Freq are same and volt are different OR
 781  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 782  * -ENOMEM      Memory allocation failure
 783  * -ENODEV      when 'operating-points' property is not found or is invalid data
 784  *              in device node.
 785  * -ENODATA     when empty 'operating-points' property is found
 786  * -EINVAL      when invalid entries are found in opp-v2 table
 787  */
 788 int dev_pm_opp_of_add_table(struct device *dev)
 789 {
 790         struct opp_table *opp_table;
 791         int ret;
 792
 793         opp_table = dev_pm_opp_get_opp_table_indexed(dev, 0);
 794         if (!opp_table)
 795                 return -ENOMEM;
 796
 797         /*
 798          * OPPs have two version of bindings now. Also try the old (v1)
 799          * bindings for backward compatibility with older dtbs.
 800          */
 801         if (opp_table->np)
 802                 ret = _of_add_opp_table_v2(dev, opp_table);
 803         else
 804                 ret = _of_add_opp_table_v1(dev, opp_table);
 805
 806         if (ret)
 807                 dev_pm_opp_put_opp_table(opp_table);
 808
 809         return ret;
 810 }
 811 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table);
 812
 813 /**
 814  * dev_pm_opp_of_add_table_indexed() - Initialize indexed opp table from device tree
 815  * @dev:        device pointer used to lookup OPP table.
 816  * @index:      Index number.
 817  *
 818  * Register the initial OPP table with the OPP library for given device only
 819  * using the "operating-points-v2" property.
 820  *
 821  * Return:
 822  * 0            On success OR
 823  *              Duplicate OPPs (both freq and volt are same) and opp->available
 824  * -EEXIST      Freq are same and volt are different OR
 825  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 826  * -ENOMEM      Memory allocation failure
 827  * -ENODEV      when 'operating-points' property is not found or is invalid data
 828  *              in device node.
 829  * -ENODATA     when empty 'operating-points' property is found
 830  * -EINVAL      when invalid entries are found in opp-v2 table
 831  */
 832 int dev_pm_opp_of_add_table_indexed(struct device *dev, int index)
 833 {
 834         struct opp_table *opp_table;
 835         int ret, count;
 836
 837         if (index) {
 838                 /*
 839                  * If only one phandle is present, then the same OPP table
 840                  * applies for all index requests.
 841                  */
 842                 count = of_count_phandle_with_args(dev->of_node,
 843                                                    "operating-points-v2", NULL);
 844                 if (count == 1)
 845                         index = 0;
 846         }
 847
 848         opp_table = dev_pm_opp_get_opp_table_indexed(dev, index);
 849         if (!opp_table)
 850                 return -ENOMEM;
 851
 852         ret = _of_add_opp_table_v2(dev, opp_table);
 853         if (ret)
 854                 dev_pm_opp_put_opp_table(opp_table);
 855
 856         return ret;
 857 }
 858 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table_indexed);
 859
 860 /* CPU device specific helpers */
 861
 862 /**
 863  * dev_pm_opp_of_cpumask_remove_table() - Removes OPP table for @cpumask
 864  * @cpumask:    cpumask for which OPP table needs to be removed
 865  *
 866  * This removes the OPP tables for CPUs present in the @cpumask.
 867  * This should be used only to remove static entries created from DT.
 868  */
 869 void dev_pm_opp_of_cpumask_remove_table(const struct cpumask *cpumask)
 870 {
 871         _dev_pm_opp_cpumask_remove_table(cpumask, -1);
 872 }
 873 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_remove_table);
 874
 875 /**
 876  * dev_pm_opp_of_cpumask_add_table() - Adds OPP table for @cpumask
 877  * @cpumask:    cpumask for which OPP table needs to be added.
 878  *
 879  * This adds the OPP tables for CPUs present in the @cpumask.
 880  */
 881 int dev_pm_opp_of_cpumask_add_table(const struct cpumask *cpumask)
 882 {
 883         struct device *cpu_dev;
 884         int cpu, ret;
 885
 886         if (WARN_ON(cpumask_empty(cpumask)))
 887                 return -ENODEV;
 888
 889         for_each_cpu(cpu, cpumask) {
 890                 cpu_dev = get_cpu_device(cpu);
 891                 if (!cpu_dev) {
 892                         pr_err("%s: failed to get cpu%d device\n", __func__,
 893                                cpu);
 894                         ret = -ENODEV;
 895                         goto remove_table;
 896                 }
 897
 898                 ret = dev_pm_opp_of_add_table(cpu_dev);
 899                 if (ret) {
 900                         /*
 901                          * OPP may get registered dynamically, don't print error
 902                          * message here.
 903                          */
 904                         pr_debug("%s: couldn't find opp table for cpu:%d, %d\n",
 905                                  __func__, cpu, ret);
 906
 907                         goto remove_table;
 908                 }
 909         }
 910
 911         return 0;
 912
 913 remove_table:
 914         /* Free all other OPPs */
 915         _dev_pm_opp_cpumask_remove_table(cpumask, cpu);
 916
 917         return ret;
 918 }
 919 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_add_table);
 920
 921 /*
 922  * Works only for OPP v2 bindings.
 923  *
 924  * Returns -ENOENT if operating-points-v2 bindings aren't supported.
 925  */
 926 /**
 927  * dev_pm_opp_of_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with
 928  *                                    @cpu_dev using operating-points-v2
 929  *                                    bindings.
 930  *
 931  * @cpu_dev:    CPU device for which we do this operation
 932  * @cpumask:    cpumask to update with information of sharing CPUs
 933  *
 934  * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev.
 935  *
 936  * Returns -ENOENT if operating-points-v2 isn't present for @cpu_dev.
 937  */
 938 int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev,
 939                                    struct cpumask *cpumask)
 940 {
 941         struct device_node *np, *tmp_np, *cpu_np;
 942         int cpu, ret = 0;
 943
 944         /* Get OPP descriptor node */
 945         np = dev_pm_opp_of_get_opp_desc_node(cpu_dev);
 946         if (!np) {
 947                 dev_dbg(cpu_dev, "%s: Couldn't find opp node.\n", __func__);
 948                 return -ENOENT;
 949         }
 950
 951         cpumask_set_cpu(cpu_dev->id, cpumask);
 952
 953         /* OPPs are shared ? */
 954         if (!of_property_read_bool(np, "opp-shared"))
 955                 goto put_cpu_node;
 956
 957         for_each_possible_cpu(cpu) {
 958                 if (cpu == cpu_dev->id)
 959                         continue;
 960
 961                 cpu_np = of_cpu_device_node_get(cpu);
 962                 if (!cpu_np) {
 963                         dev_err(cpu_dev, "%s: failed to get cpu%d node\n",
 964                                 __func__, cpu);
 965                         ret = -ENOENT;
 966                         goto put_cpu_node;
 967                 }
 968
 969                 /* Get OPP descriptor node */
 970                 tmp_np = _opp_of_get_opp_desc_node(cpu_np, 0);
 971                 of_node_put(cpu_np);
 972                 if (!tmp_np) {
 973                         pr_err("%pOF: Couldn't find opp node\n", cpu_np);
 974                         ret = -ENOENT;
 975                         goto put_cpu_node;
 976                 }
 977
 978                 /* CPUs are sharing opp node */
 979                 if (np == tmp_np)
 980                         cpumask_set_cpu(cpu, cpumask);
 981
 982                 of_node_put(tmp_np);
 983         }
 984
 985 put_cpu_node:
 986         of_node_put(np);
 987         return ret;
 988 }
 989 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus);
 990
 991 /**
 992  * of_get_required_opp_performance_state() - Search for required OPP and return its performance state.
 993  * @np: Node that contains the "required-opps" property.
 994  * @index: Index of the phandle to parse.
 995  *
 996  * Returns the performance state of the OPP pointed out by the "required-opps"
 997  * property at @index in @np.
 998  *
 999  * Return: Zero or positive performance state on success, otherwise negative
1000  * value on errors.
1001  */
1002 int of_get_required_opp_performance_state(struct device_node *np, int index)
1003 {
1004         struct dev_pm_opp *opp;
1005         struct device_node *required_np;
1006         struct opp_table *opp_table;
1007         int pstate = -EINVAL;
1008
1009         required_np = of_parse_required_opp(np, index);
1010         if (!required_np)
1011                 return -EINVAL;
1012
1013         opp_table = _find_table_of_opp_np(required_np);
1014         if (IS_ERR(opp_table)) {
1015                 pr_err("%s: Failed to find required OPP table %pOF: %ld\n",
1016                        __func__, np, PTR_ERR(opp_table));
1017                 goto put_required_np;
1018         }
1019
1020         opp = _find_opp_of_np(opp_table, required_np);
1021         if (opp) {
1022                 pstate = opp->pstate;
1023                 dev_pm_opp_put(opp);
1024         }
1025
1026         dev_pm_opp_put_opp_table(opp_table);
1027
1028 put_required_np:
1029         of_node_put(required_np);
1030
1031         return pstate;
1032 }
1033 EXPORT_SYMBOL_GPL(of_get_required_opp_performance_state);
1034
1035 /**
1036  * dev_pm_opp_get_of_node() - Gets the DT node corresponding to an opp
1037  * @opp:        opp for which DT node has to be returned for
1038  *
1039  * Return: DT node corresponding to the opp, else 0 on success.
1040  *
1041  * The caller needs to put the node with of_node_put() after using it.
1042  */
1043 struct device_node *dev_pm_opp_get_of_node(struct dev_pm_opp *opp)
1044 {
1045         if (IS_ERR_OR_NULL(opp)) {
1046                 pr_err("%s: Invalid parameters\n", __func__);
1047                 return NULL;
1048         }
1049
1050         return of_node_get(opp->np);
1051 }
1052 EXPORT_SYMBOL_GPL(dev_pm_opp_get_of_node);
1053
1054 /*
1055  * Callback function provided to the Energy Model framework upon registration.
1056  * This computes the power estimated by @CPU at @kHz if it is the frequency
1057  * of an existing OPP, or at the frequency of the first OPP above @kHz otherwise
1058  * (see dev_pm_opp_find_freq_ceil()). This function updates @kHz to the ceiled
1059  * frequency and @mW to the associated power. The power is estimated as
1060  * P = C * V^2 * f with C being the CPU's capacitance and V and f respectively
1061  * the voltage and frequency of the OPP.
1062  *
1063  * Returns -ENODEV if the CPU device cannot be found, -EINVAL if the power
1064  * calculation failed because of missing parameters, 0 otherwise.
1065  */
1066 static int __maybe_unused _get_cpu_power(unsigned long *mW, unsigned long *kHz,
1067                                          int cpu)
1068 {
1069         struct device *cpu_dev;
1070         struct dev_pm_opp *opp;
1071         struct device_node *np;
1072         unsigned long mV, Hz;
1073         u32 cap;
1074         u64 tmp;
1075         int ret;
1076
1077         cpu_dev = get_cpu_device(cpu);
1078         if (!cpu_dev)
1079                 return -ENODEV;
1080
1081         np = of_node_get(cpu_dev->of_node);
1082         if (!np)
1083                 return -EINVAL;
1084
1085         ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1086         of_node_put(np);
1087         if (ret)
1088                 return -EINVAL;
1089
1090         Hz = *kHz * 1000;
1091         opp = dev_pm_opp_find_freq_ceil(cpu_dev, &Hz);
1092         if (IS_ERR(opp))
1093                 return -EINVAL;
1094
1095         mV = dev_pm_opp_get_voltage(opp) / 1000;
1096         dev_pm_opp_put(opp);
1097         if (!mV)
1098                 return -EINVAL;
1099
1100         tmp = (u64)cap * mV * mV * (Hz / 1000000);
1101         do_div(tmp, 1000000000);
1102
1103         *mW = (unsigned long)tmp;
1104         *kHz = Hz / 1000;
1105
1106         return 0;
1107 }
1108
1109 /**
1110  * dev_pm_opp_of_register_em() - Attempt to register an Energy Model
1111  * @cpus        : CPUs for which an Energy Model has to be registered
1112  *
1113  * This checks whether the "dynamic-power-coefficient" devicetree property has
1114  * been specified, and tries to register an Energy Model with it if it has.
1115  */
1116 void dev_pm_opp_of_register_em(struct cpumask *cpus)
1117 {
1118         struct em_data_callback em_cb = EM_DATA_CB(_get_cpu_power);
1119         int ret, nr_opp, cpu = cpumask_first(cpus);
1120         struct device *cpu_dev;
1121         struct device_node *np;
1122         u32 cap;
1123
1124         cpu_dev = get_cpu_device(cpu);
1125         if (!cpu_dev)
1126                 return;
1127
1128         nr_opp = dev_pm_opp_get_opp_count(cpu_dev);
1129         if (nr_opp <= 0)
1130                 return;
1131
1132         np = of_node_get(cpu_dev->of_node);
1133         if (!np)
1134                 return;
1135
1136         /*
1137          * Register an EM only if the 'dynamic-power-coefficient' property is
1138          * set in devicetree. It is assumed the voltage values are known if that
1139          * property is set since it is useless otherwise. If voltages are not
1140          * known, just let the EM registration fail with an error to alert the
1141          * user about the inconsistent configuration.
1142          */
1143         ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1144         of_node_put(np);
1145         if (ret || !cap)
1146                 return;
1147
1148         em_register_perf_domain(cpus, nr_opp, &em_cb);
1149 }
1150 EXPORT_SYMBOL_GPL(dev_pm_opp_of_register_em);