drivers/opp/of.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Generic OPP OF helpers
   4  *
   5  * Copyright (C) 2009-2010 Texas Instruments Incorporated.
   6  *      Nishanth Menon
   7  *      Romit Dasgupta
   8  *      Kevin Hilman
   9  */
  10
  11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  12
  13 #include <linux/cpu.h>
  14 #include <linux/errno.h>
  15 #include <linux/device.h>
  16 #include <linux/of_device.h>
  17 #include <linux/pm_domain.h>
  18 #include <linux/slab.h>
  19 #include <linux/export.h>
  20 #include <linux/energy_model.h>
  21
  22 #include "opp.h"
  23
  24 /*
  25  * Returns opp descriptor node for a device node, caller must
  26  * do of_node_put().
  27  */
  28 static struct device_node *_opp_of_get_opp_desc_node(struct device_node *np,
  29                                                      int index)
  30 {
  31         /* "operating-points-v2" can be an array for power domain providers */
  32         return of_parse_phandle(np, "operating-points-v2", index);
  33 }
  34
  35 /* Returns opp descriptor node for a device, caller must do of_node_put() */
  36 struct device_node *dev_pm_opp_of_get_opp_desc_node(struct device *dev)
  37 {
  38         return _opp_of_get_opp_desc_node(dev->of_node, 0);
  39 }
  40 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_opp_desc_node);
  41
  42 struct opp_table *_managed_opp(struct device *dev, int index)
  43 {
  44         struct opp_table *opp_table, *managed_table = NULL;
  45         struct device_node *np;
  46
  47         np = _opp_of_get_opp_desc_node(dev->of_node, index);
  48         if (!np)
  49                 return NULL;
  50
  51         list_for_each_entry(opp_table, &opp_tables, node) {
  52                 if (opp_table->np == np) {
  53                         /*
  54                          * Multiple devices can point to the same OPP table and
  55                          * so will have same node-pointer, np.
  56                          *
  57                          * But the OPPs will be considered as shared only if the
  58                          * OPP table contains a "opp-shared" property.
  59                          */
  60                         if (opp_table->shared_opp == OPP_TABLE_ACCESS_SHARED) {
  61                                 _get_opp_table_kref(opp_table);
  62                                 managed_table = opp_table;
  63                         }
  64
  65                         break;
  66                 }
  67         }
  68
  69         of_node_put(np);
  70
  71         return managed_table;
  72 }
  73
  74 /* The caller must call dev_pm_opp_put() after the OPP is used */
  75 static struct dev_pm_opp *_find_opp_of_np(struct opp_table *opp_table,
  76                                           struct device_node *opp_np)
  77 {
  78         struct dev_pm_opp *opp;
  79
  80         mutex_lock(&opp_table->lock);
  81
  82         list_for_each_entry(opp, &opp_table->opp_list, node) {
  83                 if (opp->np == opp_np) {
  84                         dev_pm_opp_get(opp);
  85                         mutex_unlock(&opp_table->lock);
  86                         return opp;
  87                 }
  88         }
  89
  90         mutex_unlock(&opp_table->lock);
  91
  92         return NULL;
  93 }
  94
  95 static struct device_node *of_parse_required_opp(struct device_node *np,
  96                                                  int index)
  97 {
  98         return of_parse_phandle(np, "required-opps", index);
  99 }
 100
 101 /* The caller must call dev_pm_opp_put_opp_table() after the table is used */
 102 static struct opp_table *_find_table_of_opp_np(struct device_node *opp_np)
 103 {
 104         struct opp_table *opp_table;
 105         struct device_node *opp_table_np;
 106
 107         lockdep_assert_held(&opp_table_lock);
 108
 109         opp_table_np = of_get_parent(opp_np);
 110         if (!opp_table_np)
 111                 goto err;
 112
 113         /* It is safe to put the node now as all we need now is its address */
 114         of_node_put(opp_table_np);
 115
 116         list_for_each_entry(opp_table, &opp_tables, node) {
 117                 if (opp_table_np == opp_table->np) {
 118                         _get_opp_table_kref(opp_table);
 119                         return opp_table;
 120                 }
 121         }
 122
 123 err:
 124         return ERR_PTR(-ENODEV);
 125 }
 126
 127 /* Free resources previously acquired by _opp_table_alloc_required_tables() */
 128 static void _opp_table_free_required_tables(struct opp_table *opp_table)
 129 {
 130         struct opp_table **required_opp_tables = opp_table->required_opp_tables;
 131         int i;
 132
 133         if (!required_opp_tables)
 134                 return;
 135
 136         for (i = 0; i < opp_table->required_opp_count; i++) {
 137                 if (IS_ERR_OR_NULL(required_opp_tables[i]))
 138                         break;
 139
 140                 dev_pm_opp_put_opp_table(required_opp_tables[i]);
 141         }
 142
 143         kfree(required_opp_tables);
 144
 145         opp_table->required_opp_count = 0;
 146         opp_table->required_opp_tables = NULL;
 147 }
 148
 149 /*
 150  * Populate all devices and opp tables which are part of "required-opps" list.
 151  * Checking only the first OPP node should be enough.
 152  */
 153 static void _opp_table_alloc_required_tables(struct opp_table *opp_table,
 154                                              struct device *dev,
 155                                              struct device_node *opp_np)
 156 {
 157         struct opp_table **required_opp_tables;
 158         struct device_node *required_np, *np;
 159         int count, i;
 160
 161         /* Traversing the first OPP node is all we need */
 162         np = of_get_next_available_child(opp_np, NULL);
 163         if (!np) {
 164                 dev_err(dev, "Empty OPP table\n");
 165                 return;
 166         }
 167
 168         count = of_count_phandle_with_args(np, "required-opps", NULL);
 169         if (!count)
 170                 goto put_np;
 171
 172         required_opp_tables = kcalloc(count, sizeof(*required_opp_tables),
 173                                       GFP_KERNEL);
 174         if (!required_opp_tables)
 175                 goto put_np;
 176
 177         opp_table->required_opp_tables = required_opp_tables;
 178         opp_table->required_opp_count = count;
 179
 180         for (i = 0; i < count; i++) {
 181                 required_np = of_parse_required_opp(np, i);
 182                 if (!required_np)
 183                         goto free_required_tables;
 184
 185                 required_opp_tables[i] = _find_table_of_opp_np(required_np);
 186                 of_node_put(required_np);
 187
 188                 if (IS_ERR(required_opp_tables[i]))
 189                         goto free_required_tables;
 190
 191                 /*
 192                  * We only support genpd's OPPs in the "required-opps" for now,
 193                  * as we don't know how much about other cases. Error out if the
 194                  * required OPP doesn't belong to a genpd.
 195                  */
 196                 if (!required_opp_tables[i]->is_genpd) {
 197                         dev_err(dev, "required-opp doesn't belong to genpd: %pOF\n",
 198                                 required_np);
 199                         goto free_required_tables;
 200                 }
 201         }
 202
 203         goto put_np;
 204
 205 free_required_tables:
 206         _opp_table_free_required_tables(opp_table);
 207 put_np:
 208         of_node_put(np);
 209 }
 210
 211 void _of_init_opp_table(struct opp_table *opp_table, struct device *dev,
 212                         int index)
 213 {
 214         struct device_node *np, *opp_np;
 215         u32 val;
 216
 217         /*
 218          * Only required for backward compatibility with v1 bindings, but isn't
 219          * harmful for other cases. And so we do it unconditionally.
 220          */
 221         np = of_node_get(dev->of_node);
 222         if (!np)
 223                 return;
 224
 225         if (!of_property_read_u32(np, "clock-latency", &val))
 226                 opp_table->clock_latency_ns_max = val;
 227         of_property_read_u32(np, "voltage-tolerance",
 228                              &opp_table->voltage_tolerance_v1);
 229
 230         if (of_find_property(np, "#power-domain-cells", NULL))
 231                 opp_table->is_genpd = true;
 232
 233         /* Get OPP table node */
 234         opp_np = _opp_of_get_opp_desc_node(np, index);
 235         of_node_put(np);
 236
 237         if (!opp_np)
 238                 return;
 239
 240         if (of_property_read_bool(opp_np, "opp-shared"))
 241                 opp_table->shared_opp = OPP_TABLE_ACCESS_SHARED;
 242         else
 243                 opp_table->shared_opp = OPP_TABLE_ACCESS_EXCLUSIVE;
 244
 245         opp_table->np = opp_np;
 246
 247         _opp_table_alloc_required_tables(opp_table, dev, opp_np);
 248         of_node_put(opp_np);
 249 }
 250
 251 void _of_clear_opp_table(struct opp_table *opp_table)
 252 {
 253         _opp_table_free_required_tables(opp_table);
 254 }
 255
 256 /*
 257  * Release all resources previously acquired with a call to
 258  * _of_opp_alloc_required_opps().
 259  */
 260 void _of_opp_free_required_opps(struct opp_table *opp_table,
 261                                 struct dev_pm_opp *opp)
 262 {
 263         struct dev_pm_opp **required_opps = opp->required_opps;
 264         int i;
 265
 266         if (!required_opps)
 267                 return;
 268
 269         for (i = 0; i < opp_table->required_opp_count; i++) {
 270                 if (!required_opps[i])
 271                         break;
 272
 273                 /* Put the reference back */
 274                 dev_pm_opp_put(required_opps[i]);
 275         }
 276
 277         kfree(required_opps);
 278         opp->required_opps = NULL;
 279 }
 280
 281 /* Populate all required OPPs which are part of "required-opps" list */
 282 static int _of_opp_alloc_required_opps(struct opp_table *opp_table,
 283                                        struct dev_pm_opp *opp)
 284 {
 285         struct dev_pm_opp **required_opps;
 286         struct opp_table *required_table;
 287         struct device_node *np;
 288         int i, ret, count = opp_table->required_opp_count;
 289
 290         if (!count)
 291                 return 0;
 292
 293         required_opps = kcalloc(count, sizeof(*required_opps), GFP_KERNEL);
 294         if (!required_opps)
 295                 return -ENOMEM;
 296
 297         opp->required_opps = required_opps;
 298
 299         for (i = 0; i < count; i++) {
 300                 required_table = opp_table->required_opp_tables[i];
 301
 302                 np = of_parse_required_opp(opp->np, i);
 303                 if (unlikely(!np)) {
 304                         ret = -ENODEV;
 305                         goto free_required_opps;
 306                 }
 307
 308                 required_opps[i] = _find_opp_of_np(required_table, np);
 309                 of_node_put(np);
 310
 311                 if (!required_opps[i]) {
 312                         pr_err("%s: Unable to find required OPP node: %pOF (%d)\n",
 313                                __func__, opp->np, i);
 314                         ret = -ENODEV;
 315                         goto free_required_opps;
 316                 }
 317         }
 318
 319         return 0;
 320
 321 free_required_opps:
 322         _of_opp_free_required_opps(opp_table, opp);
 323
 324         return ret;
 325 }
 326
 327 static bool _opp_is_supported(struct device *dev, struct opp_table *opp_table,
 328                               struct device_node *np)
 329 {
 330         unsigned int count = opp_table->supported_hw_count;
 331         u32 version;
 332         int ret;
 333
 334         if (!opp_table->supported_hw) {
 335                 /*
 336                  * In the case that no supported_hw has been set by the
 337                  * platform but there is an opp-supported-hw value set for
 338                  * an OPP then the OPP should not be enabled as there is
 339                  * no way to see if the hardware supports it.
 340                  */
 341                 if (of_find_property(np, "opp-supported-hw", NULL))
 342                         return false;
 343                 else
 344                         return true;
 345         }
 346
 347         while (count--) {
 348                 ret = of_property_read_u32_index(np, "opp-supported-hw", count,
 349                                                  &version);
 350                 if (ret) {
 351                         dev_warn(dev, "%s: failed to read opp-supported-hw property at index %d: %d\n",
 352                                  __func__, count, ret);
 353                         return false;
 354                 }
 355
 356                 /* Both of these are bitwise masks of the versions */
 357                 if (!(version & opp_table->supported_hw[count]))
 358                         return false;
 359         }
 360
 361         return true;
 362 }
 363
 364 static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,
 365                               struct opp_table *opp_table)
 366 {
 367         u32 *microvolt, *microamp = NULL;
 368         int supplies = opp_table->regulator_count, vcount, icount, ret, i, j;
 369         struct property *prop = NULL;
 370         char name[NAME_MAX];
 371
 372         /* Search for "opp-microvolt-<name>" */
 373         if (opp_table->prop_name) {
 374                 snprintf(name, sizeof(name), "opp-microvolt-%s",
 375                          opp_table->prop_name);
 376                 prop = of_find_property(opp->np, name, NULL);
 377         }
 378
 379         if (!prop) {
 380                 /* Search for "opp-microvolt" */
 381                 sprintf(name, "opp-microvolt");
 382                 prop = of_find_property(opp->np, name, NULL);
 383
 384                 /* Missing property isn't a problem, but an invalid entry is */
 385                 if (!prop) {
 386                         if (unlikely(supplies == -1)) {
 387                                 /* Initialize regulator_count */
 388                                 opp_table->regulator_count = 0;
 389                                 return 0;
 390                         }
 391
 392                         if (!supplies)
 393                                 return 0;
 394
 395                         dev_err(dev, "%s: opp-microvolt missing although OPP managing regulators\n",
 396                                 __func__);
 397                         return -EINVAL;
 398                 }
 399         }
 400
 401         if (unlikely(supplies == -1)) {
 402                 /* Initialize regulator_count */
 403                 supplies = opp_table->regulator_count = 1;
 404         } else if (unlikely(!supplies)) {
 405                 dev_err(dev, "%s: opp-microvolt wasn't expected\n", __func__);
 406                 return -EINVAL;
 407         }
 408
 409         vcount = of_property_count_u32_elems(opp->np, name);
 410         if (vcount < 0) {
 411                 dev_err(dev, "%s: Invalid %s property (%d)\n",
 412                         __func__, name, vcount);
 413                 return vcount;
 414         }
 415
 416         /* There can be one or three elements per supply */
 417         if (vcount != supplies && vcount != supplies * 3) {
 418                 dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
 419                         __func__, name, vcount, supplies);
 420                 return -EINVAL;
 421         }
 422
 423         microvolt = kmalloc_array(vcount, sizeof(*microvolt), GFP_KERNEL);
 424         if (!microvolt)
 425                 return -ENOMEM;
 426
 427         ret = of_property_read_u32_array(opp->np, name, microvolt, vcount);
 428         if (ret) {
 429                 dev_err(dev, "%s: error parsing %s: %d\n", __func__, name, ret);
 430                 ret = -EINVAL;
 431                 goto free_microvolt;
 432         }
 433
 434         /* Search for "opp-microamp-<name>" */
 435         prop = NULL;
 436         if (opp_table->prop_name) {
 437                 snprintf(name, sizeof(name), "opp-microamp-%s",
 438                          opp_table->prop_name);
 439                 prop = of_find_property(opp->np, name, NULL);
 440         }
 441
 442         if (!prop) {
 443                 /* Search for "opp-microamp" */
 444                 sprintf(name, "opp-microamp");
 445                 prop = of_find_property(opp->np, name, NULL);
 446         }
 447
 448         if (prop) {
 449                 icount = of_property_count_u32_elems(opp->np, name);
 450                 if (icount < 0) {
 451                         dev_err(dev, "%s: Invalid %s property (%d)\n", __func__,
 452                                 name, icount);
 453                         ret = icount;
 454                         goto free_microvolt;
 455                 }
 456
 457                 if (icount != supplies) {
 458                         dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
 459                                 __func__, name, icount, supplies);
 460                         ret = -EINVAL;
 461                         goto free_microvolt;
 462                 }
 463
 464                 microamp = kmalloc_array(icount, sizeof(*microamp), GFP_KERNEL);
 465                 if (!microamp) {
 466                         ret = -EINVAL;
 467                         goto free_microvolt;
 468                 }
 469
 470                 ret = of_property_read_u32_array(opp->np, name, microamp,
 471                                                  icount);
 472                 if (ret) {
 473                         dev_err(dev, "%s: error parsing %s: %d\n", __func__,
 474                                 name, ret);
 475                         ret = -EINVAL;
 476                         goto free_microamp;
 477                 }
 478         }
 479
 480         for (i = 0, j = 0; i < supplies; i++) {
 481                 opp->supplies[i].u_volt = microvolt[j++];
 482
 483                 if (vcount == supplies) {
 484                         opp->supplies[i].u_volt_min = opp->supplies[i].u_volt;
 485                         opp->supplies[i].u_volt_max = opp->supplies[i].u_volt;
 486                 } else {
 487                         opp->supplies[i].u_volt_min = microvolt[j++];
 488                         opp->supplies[i].u_volt_max = microvolt[j++];
 489                 }
 490
 491                 if (microamp)
 492                         opp->supplies[i].u_amp = microamp[i];
 493         }
 494
 495 free_microamp:
 496         kfree(microamp);
 497 free_microvolt:
 498         kfree(microvolt);
 499
 500         return ret;
 501 }
 502
 503 /**
 504  * dev_pm_opp_of_remove_table() - Free OPP table entries created from static DT
 505  *                                entries
 506  * @dev:        device pointer used to lookup OPP table.
 507  *
 508  * Free OPPs created using static entries present in DT.
 509  */
 510 void dev_pm_opp_of_remove_table(struct device *dev)
 511 {
 512         _dev_pm_opp_find_and_remove_table(dev);
 513 }
 514 EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table);
 515
 516 /**
 517  * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings)
 518  * @opp_table:  OPP table
 519  * @dev:        device for which we do this operation
 520  * @np:         device node
 521  *
 522  * This function adds an opp definition to the opp table and returns status. The
 523  * opp can be controlled using dev_pm_opp_enable/disable functions and may be
 524  * removed by dev_pm_opp_remove.
 525  *
 526  * Return:
 527  * Valid OPP pointer:
 528  *              On success
 529  * NULL:
 530  *              Duplicate OPPs (both freq and volt are same) and opp->available
 531  *              OR if the OPP is not supported by hardware.
 532  * ERR_PTR(-EEXIST):
 533  *              Freq are same and volt are different OR
 534  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 535  * ERR_PTR(-ENOMEM):
 536  *              Memory allocation failure
 537  * ERR_PTR(-EINVAL):
 538  *              Failed parsing the OPP node
 539  */
 540 static struct dev_pm_opp *_opp_add_static_v2(struct opp_table *opp_table,
 541                 struct device *dev, struct device_node *np)
 542 {
 543         struct dev_pm_opp *new_opp;
 544         u64 rate = 0;
 545         u32 val;
 546         int ret;
 547         bool rate_not_available = false;
 548
 549         new_opp = _opp_allocate(opp_table);
 550         if (!new_opp)
 551                 return ERR_PTR(-ENOMEM);
 552
 553         ret = of_property_read_u64(np, "opp-hz", &rate);
 554         if (ret < 0) {
 555                 /* "opp-hz" is optional for devices like power domains. */
 556                 if (!opp_table->is_genpd) {
 557                         dev_err(dev, "%s: opp-hz not found\n", __func__);
 558                         goto free_opp;
 559                 }
 560
 561                 rate_not_available = true;
 562         } else {
 563                 /*
 564                  * Rate is defined as an unsigned long in clk API, and so
 565                  * casting explicitly to its type. Must be fixed once rate is 64
 566                  * bit guaranteed in clk API.
 567                  */
 568                 new_opp->rate = (unsigned long)rate;
 569         }
 570
 571         of_property_read_u32(np, "opp-level", &new_opp->level);
 572
 573         /* Check if the OPP supports hardware's hierarchy of versions or not */
 574         if (!_opp_is_supported(dev, opp_table, np)) {
 575                 dev_dbg(dev, "OPP not supported by hardware: %llu\n", rate);
 576                 goto free_opp;
 577         }
 578
 579         new_opp->turbo = of_property_read_bool(np, "turbo-mode");
 580
 581         new_opp->np = np;
 582         new_opp->dynamic = false;
 583         new_opp->available = true;
 584
 585         ret = _of_opp_alloc_required_opps(opp_table, new_opp);
 586         if (ret)
 587                 goto free_opp;
 588
 589         if (!of_property_read_u32(np, "clock-latency-ns", &val))
 590                 new_opp->clock_latency_ns = val;
 591
 592         ret = opp_parse_supplies(new_opp, dev, opp_table);
 593         if (ret)
 594                 goto free_required_opps;
 595
 596         if (opp_table->is_genpd)
 597                 new_opp->pstate = pm_genpd_opp_to_performance_state(dev, new_opp);
 598
 599         ret = _opp_add(dev, new_opp, opp_table, rate_not_available);
 600         if (ret) {
 601                 /* Don't return error for duplicate OPPs */
 602                 if (ret == -EBUSY)
 603                         ret = 0;
 604                 goto free_required_opps;
 605         }
 606
 607         /* OPP to select on device suspend */
 608         if (of_property_read_bool(np, "opp-suspend")) {
 609                 if (opp_table->suspend_opp) {
 610                         /* Pick the OPP with higher rate as suspend OPP */
 611                         if (new_opp->rate > opp_table->suspend_opp->rate) {
 612                                 opp_table->suspend_opp->suspend = false;
 613                                 new_opp->suspend = true;
 614                                 opp_table->suspend_opp = new_opp;
 615                         }
 616                 } else {
 617                         new_opp->suspend = true;
 618                         opp_table->suspend_opp = new_opp;
 619                 }
 620         }
 621
 622         if (new_opp->clock_latency_ns > opp_table->clock_latency_ns_max)
 623                 opp_table->clock_latency_ns_max = new_opp->clock_latency_ns;
 624
 625         pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu\n",
 626                  __func__, new_opp->turbo, new_opp->rate,
 627                  new_opp->supplies[0].u_volt, new_opp->supplies[0].u_volt_min,
 628                  new_opp->supplies[0].u_volt_max, new_opp->clock_latency_ns);
 629
 630         /*
 631          * Notify the changes in the availability of the operable
 632          * frequency/voltage list.
 633          */
 634         blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ADD, new_opp);
 635         return new_opp;
 636
 637 free_required_opps:
 638         _of_opp_free_required_opps(opp_table, new_opp);
 639 free_opp:
 640         _opp_free(new_opp);
 641
 642         return ret ? ERR_PTR(ret) : NULL;
 643 }
 644
 645 /* Initializes OPP tables based on new bindings */
 646 static int _of_add_opp_table_v2(struct device *dev, struct opp_table *opp_table)
 647 {
 648         struct device_node *np;
 649         int ret, count = 0, pstate_count = 0;
 650         struct dev_pm_opp *opp;
 651
 652         /* OPP table is already initialized for the device */
 653         mutex_lock(&opp_table->lock);
 654         if (opp_table->parsed_static_opps) {
 655                 opp_table->parsed_static_opps++;
 656                 mutex_unlock(&opp_table->lock);
 657                 return 0;
 658         }
 659
 660         opp_table->parsed_static_opps = 1;
 661         mutex_unlock(&opp_table->lock);
 662
 663         /* We have opp-table node now, iterate over it and add OPPs */
 664         for_each_available_child_of_node(opp_table->np, np) {
 665                 opp = _opp_add_static_v2(opp_table, dev, np);
 666                 if (IS_ERR(opp)) {
 667                         ret = PTR_ERR(opp);
 668                         dev_err(dev, "%s: Failed to add OPP, %d\n", __func__,
 669                                 ret);
 670                         of_node_put(np);
 671                         goto remove_static_opp;
 672                 } else if (opp) {
 673                         count++;
 674                 }
 675         }
 676
 677         /* There should be one or more OPPs defined */
 678         if (!count) {
 679                 dev_err(dev, "%s: no supported OPPs", __func__);
 680                 ret = -ENOENT;
 681                 goto remove_static_opp;
 682         }
 683
 684         list_for_each_entry(opp, &opp_table->opp_list, node)
 685                 pstate_count += !!opp->pstate;
 686
 687         /* Either all or none of the nodes shall have performance state set */
 688         if (pstate_count && pstate_count != count) {
 689                 dev_err(dev, "Not all nodes have performance state set (%d: %d)\n",
 690                         count, pstate_count);
 691                 ret = -ENOENT;
 692                 goto remove_static_opp;
 693         }
 694
 695         if (pstate_count)
 696                 opp_table->genpd_performance_state = true;
 697
 698         return 0;
 699
 700 remove_static_opp:
 701         _opp_remove_all_static(opp_table);
 702
 703         return ret;
 704 }
 705
 706 /* Initializes OPP tables based on old-deprecated bindings */
 707 static int _of_add_opp_table_v1(struct device *dev, struct opp_table *opp_table)
 708 {
 709         const struct property *prop;
 710         const __be32 *val;
 711         int nr, ret = 0;
 712
 713         prop = of_find_property(dev->of_node, "operating-points", NULL);
 714         if (!prop)
 715                 return -ENODEV;
 716         if (!prop->value)
 717                 return -ENODATA;
 718
 719         /*
 720          * Each OPP is a set of tuples consisting of frequency and
 721          * voltage like <freq-kHz vol-uV>.
 722          */
 723         nr = prop->length / sizeof(u32);
 724         if (nr % 2) {
 725                 dev_err(dev, "%s: Invalid OPP table\n", __func__);
 726                 return -EINVAL;
 727         }
 728
 729         mutex_lock(&opp_table->lock);
 730         opp_table->parsed_static_opps = 1;
 731         mutex_unlock(&opp_table->lock);
 732
 733         val = prop->value;
 734         while (nr) {
 735                 unsigned long freq = be32_to_cpup(val++) * 1000;
 736                 unsigned long volt = be32_to_cpup(val++);
 737
 738                 ret = _opp_add_v1(opp_table, dev, freq, volt, false);
 739                 if (ret) {
 740                         dev_err(dev, "%s: Failed to add OPP %ld (%d)\n",
 741                                 __func__, freq, ret);
 742                         _opp_remove_all_static(opp_table);
 743                         return ret;
 744                 }
 745                 nr -= 2;
 746         }
 747
 748         return ret;
 749 }
 750
 751 /**
 752  * dev_pm_opp_of_add_table() - Initialize opp table from device tree
 753  * @dev:        device pointer used to lookup OPP table.
 754  *
 755  * Register the initial OPP table with the OPP library for given device.
 756  *
 757  * Return:
 758  * 0            On success OR
 759  *              Duplicate OPPs (both freq and volt are same) and opp->available
 760  * -EEXIST      Freq are same and volt are different OR
 761  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 762  * -ENOMEM      Memory allocation failure
 763  * -ENODEV      when 'operating-points' property is not found or is invalid data
 764  *              in device node.
 765  * -ENODATA     when empty 'operating-points' property is found
 766  * -EINVAL      when invalid entries are found in opp-v2 table
 767  */
 768 int dev_pm_opp_of_add_table(struct device *dev)
 769 {
 770         struct opp_table *opp_table;
 771         int ret;
 772
 773         opp_table = dev_pm_opp_get_opp_table_indexed(dev, 0);
 774         if (!opp_table)
 775                 return -ENOMEM;
 776
 777         /*
 778          * OPPs have two version of bindings now. Also try the old (v1)
 779          * bindings for backward compatibility with older dtbs.
 780          */
 781         if (opp_table->np)
 782                 ret = _of_add_opp_table_v2(dev, opp_table);
 783         else
 784                 ret = _of_add_opp_table_v1(dev, opp_table);
 785
 786         if (ret)
 787                 dev_pm_opp_put_opp_table(opp_table);
 788
 789         return ret;
 790 }
 791 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table);
 792
 793 /**
 794  * dev_pm_opp_of_add_table_indexed() - Initialize indexed opp table from device tree
 795  * @dev:        device pointer used to lookup OPP table.
 796  * @index:      Index number.
 797  *
 798  * Register the initial OPP table with the OPP library for given device only
 799  * using the "operating-points-v2" property.
 800  *
 801  * Return:
 802  * 0            On success OR
 803  *              Duplicate OPPs (both freq and volt are same) and opp->available
 804  * -EEXIST      Freq are same and volt are different OR
 805  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 806  * -ENOMEM      Memory allocation failure
 807  * -ENODEV      when 'operating-points' property is not found or is invalid data
 808  *              in device node.
 809  * -ENODATA     when empty 'operating-points' property is found
 810  * -EINVAL      when invalid entries are found in opp-v2 table
 811  */
 812 int dev_pm_opp_of_add_table_indexed(struct device *dev, int index)
 813 {
 814         struct opp_table *opp_table;
 815         int ret, count;
 816
 817         if (index) {
 818                 /*
 819                  * If only one phandle is present, then the same OPP table
 820                  * applies for all index requests.
 821                  */
 822                 count = of_count_phandle_with_args(dev->of_node,
 823                                                    "operating-points-v2", NULL);
 824                 if (count == 1)
 825                         index = 0;
 826         }
 827
 828         opp_table = dev_pm_opp_get_opp_table_indexed(dev, index);
 829         if (!opp_table)
 830                 return -ENOMEM;
 831
 832         ret = _of_add_opp_table_v2(dev, opp_table);
 833         if (ret)
 834                 dev_pm_opp_put_opp_table(opp_table);
 835
 836         return ret;
 837 }
 838 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table_indexed);
 839
 840 /* CPU device specific helpers */
 841
 842 /**
 843  * dev_pm_opp_of_cpumask_remove_table() - Removes OPP table for @cpumask
 844  * @cpumask:    cpumask for which OPP table needs to be removed
 845  *
 846  * This removes the OPP tables for CPUs present in the @cpumask.
 847  * This should be used only to remove static entries created from DT.
 848  */
 849 void dev_pm_opp_of_cpumask_remove_table(const struct cpumask *cpumask)
 850 {
 851         _dev_pm_opp_cpumask_remove_table(cpumask, -1);
 852 }
 853 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_remove_table);
 854
 855 /**
 856  * dev_pm_opp_of_cpumask_add_table() - Adds OPP table for @cpumask
 857  * @cpumask:    cpumask for which OPP table needs to be added.
 858  *
 859  * This adds the OPP tables for CPUs present in the @cpumask.
 860  */
 861 int dev_pm_opp_of_cpumask_add_table(const struct cpumask *cpumask)
 862 {
 863         struct device *cpu_dev;
 864         int cpu, ret;
 865
 866         if (WARN_ON(cpumask_empty(cpumask)))
 867                 return -ENODEV;
 868
 869         for_each_cpu(cpu, cpumask) {
 870                 cpu_dev = get_cpu_device(cpu);
 871                 if (!cpu_dev) {
 872                         pr_err("%s: failed to get cpu%d device\n", __func__,
 873                                cpu);
 874                         ret = -ENODEV;
 875                         goto remove_table;
 876                 }
 877
 878                 ret = dev_pm_opp_of_add_table(cpu_dev);
 879                 if (ret) {
 880                         /*
 881                          * OPP may get registered dynamically, don't print error
 882                          * message here.
 883                          */
 884                         pr_debug("%s: couldn't find opp table for cpu:%d, %d\n",
 885                                  __func__, cpu, ret);
 886
 887                         goto remove_table;
 888                 }
 889         }
 890
 891         return 0;
 892
 893 remove_table:
 894         /* Free all other OPPs */
 895         _dev_pm_opp_cpumask_remove_table(cpumask, cpu);
 896
 897         return ret;
 898 }
 899 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_add_table);
 900
 901 /*
 902  * Works only for OPP v2 bindings.
 903  *
 904  * Returns -ENOENT if operating-points-v2 bindings aren't supported.
 905  */
 906 /**
 907  * dev_pm_opp_of_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with
 908  *                                    @cpu_dev using operating-points-v2
 909  *                                    bindings.
 910  *
 911  * @cpu_dev:    CPU device for which we do this operation
 912  * @cpumask:    cpumask to update with information of sharing CPUs
 913  *
 914  * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev.
 915  *
 916  * Returns -ENOENT if operating-points-v2 isn't present for @cpu_dev.
 917  */
 918 int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev,
 919                                    struct cpumask *cpumask)
 920 {
 921         struct device_node *np, *tmp_np, *cpu_np;
 922         int cpu, ret = 0;
 923
 924         /* Get OPP descriptor node */
 925         np = dev_pm_opp_of_get_opp_desc_node(cpu_dev);
 926         if (!np) {
 927                 dev_dbg(cpu_dev, "%s: Couldn't find opp node.\n", __func__);
 928                 return -ENOENT;
 929         }
 930
 931         cpumask_set_cpu(cpu_dev->id, cpumask);
 932
 933         /* OPPs are shared ? */
 934         if (!of_property_read_bool(np, "opp-shared"))
 935                 goto put_cpu_node;
 936
 937         for_each_possible_cpu(cpu) {
 938                 if (cpu == cpu_dev->id)
 939                         continue;
 940
 941                 cpu_np = of_cpu_device_node_get(cpu);
 942                 if (!cpu_np) {
 943                         dev_err(cpu_dev, "%s: failed to get cpu%d node\n",
 944                                 __func__, cpu);
 945                         ret = -ENOENT;
 946                         goto put_cpu_node;
 947                 }
 948
 949                 /* Get OPP descriptor node */
 950                 tmp_np = _opp_of_get_opp_desc_node(cpu_np, 0);
 951                 of_node_put(cpu_np);
 952                 if (!tmp_np) {
 953                         pr_err("%pOF: Couldn't find opp node\n", cpu_np);
 954                         ret = -ENOENT;
 955                         goto put_cpu_node;
 956                 }
 957
 958                 /* CPUs are sharing opp node */
 959                 if (np == tmp_np)
 960                         cpumask_set_cpu(cpu, cpumask);
 961
 962                 of_node_put(tmp_np);
 963         }
 964
 965 put_cpu_node:
 966         of_node_put(np);
 967         return ret;
 968 }
 969 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus);
 970
 971 /**
 972  * of_get_required_opp_performance_state() - Search for required OPP and return its performance state.
 973  * @np: Node that contains the "required-opps" property.
 974  * @index: Index of the phandle to parse.
 975  *
 976  * Returns the performance state of the OPP pointed out by the "required-opps"
 977  * property at @index in @np.
 978  *
 979  * Return: Zero or positive performance state on success, otherwise negative
 980  * value on errors.
 981  */
 982 int of_get_required_opp_performance_state(struct device_node *np, int index)
 983 {
 984         struct dev_pm_opp *opp;
 985         struct device_node *required_np;
 986         struct opp_table *opp_table;
 987         int pstate = -EINVAL;
 988
 989         required_np = of_parse_required_opp(np, index);
 990         if (!required_np)
 991                 return -ENODEV;
 992
 993         opp_table = _find_table_of_opp_np(required_np);
 994         if (IS_ERR(opp_table)) {
 995                 pr_err("%s: Failed to find required OPP table %pOF: %ld\n",
 996                        __func__, np, PTR_ERR(opp_table));
 997                 goto put_required_np;
 998         }
 999
1000         opp = _find_opp_of_np(opp_table, required_np);
1001         if (opp) {
1002                 pstate = opp->pstate;
1003                 dev_pm_opp_put(opp);
1004         }
1005
1006         dev_pm_opp_put_opp_table(opp_table);
1007
1008 put_required_np:
1009         of_node_put(required_np);
1010
1011         return pstate;
1012 }
1013 EXPORT_SYMBOL_GPL(of_get_required_opp_performance_state);
1014
1015 /**
1016  * dev_pm_opp_get_of_node() - Gets the DT node corresponding to an opp
1017  * @opp:        opp for which DT node has to be returned for
1018  *
1019  * Return: DT node corresponding to the opp, else 0 on success.
1020  *
1021  * The caller needs to put the node with of_node_put() after using it.
1022  */
1023 struct device_node *dev_pm_opp_get_of_node(struct dev_pm_opp *opp)
1024 {
1025         if (IS_ERR_OR_NULL(opp)) {
1026                 pr_err("%s: Invalid parameters\n", __func__);
1027                 return NULL;
1028         }
1029
1030         return of_node_get(opp->np);
1031 }
1032 EXPORT_SYMBOL_GPL(dev_pm_opp_get_of_node);
1033
1034 /*
1035  * Callback function provided to the Energy Model framework upon registration.
1036  * This computes the power estimated by @CPU at @kHz if it is the frequency
1037  * of an existing OPP, or at the frequency of the first OPP above @kHz otherwise
1038  * (see dev_pm_opp_find_freq_ceil()). This function updates @kHz to the ceiled
1039  * frequency and @mW to the associated power. The power is estimated as
1040  * P = C * V^2 * f with C being the CPU's capacitance and V and f respectively
1041  * the voltage and frequency of the OPP.
1042  *
1043  * Returns -ENODEV if the CPU device cannot be found, -EINVAL if the power
1044  * calculation failed because of missing parameters, 0 otherwise.
1045  */
1046 static int __maybe_unused _get_cpu_power(unsigned long *mW, unsigned long *kHz,
1047                                          int cpu)
1048 {
1049         struct device *cpu_dev;
1050         struct dev_pm_opp *opp;
1051         struct device_node *np;
1052         unsigned long mV, Hz;
1053         u32 cap;
1054         u64 tmp;
1055         int ret;
1056
1057         cpu_dev = get_cpu_device(cpu);
1058         if (!cpu_dev)
1059                 return -ENODEV;
1060
1061         np = of_node_get(cpu_dev->of_node);
1062         if (!np)
1063                 return -EINVAL;
1064
1065         ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1066         of_node_put(np);
1067         if (ret)
1068                 return -EINVAL;
1069
1070         Hz = *kHz * 1000;
1071         opp = dev_pm_opp_find_freq_ceil(cpu_dev, &Hz);
1072         if (IS_ERR(opp))
1073                 return -EINVAL;
1074
1075         mV = dev_pm_opp_get_voltage(opp) / 1000;
1076         dev_pm_opp_put(opp);
1077         if (!mV)
1078                 return -EINVAL;
1079
1080         tmp = (u64)cap * mV * mV * (Hz / 1000000);
1081         do_div(tmp, 1000000000);
1082
1083         *mW = (unsigned long)tmp;
1084         *kHz = Hz / 1000;
1085
1086         return 0;
1087 }
1088
1089 /**
1090  * dev_pm_opp_of_register_em() - Attempt to register an Energy Model
1091  * @cpus        : CPUs for which an Energy Model has to be registered
1092  *
1093  * This checks whether the "dynamic-power-coefficient" devicetree property has
1094  * been specified, and tries to register an Energy Model with it if it has.
1095  */
1096 void dev_pm_opp_of_register_em(struct cpumask *cpus)
1097 {
1098         struct em_data_callback em_cb = EM_DATA_CB(_get_cpu_power);
1099         int ret, nr_opp, cpu = cpumask_first(cpus);
1100         struct device *cpu_dev;
1101         struct device_node *np;
1102         u32 cap;
1103
1104         cpu_dev = get_cpu_device(cpu);
1105         if (!cpu_dev)
1106                 return;
1107
1108         nr_opp = dev_pm_opp_get_opp_count(cpu_dev);
1109         if (nr_opp <= 0)
1110                 return;
1111
1112         np = of_node_get(cpu_dev->of_node);
1113         if (!np)
1114                 return;
1115
1116         /*
1117          * Register an EM only if the 'dynamic-power-coefficient' property is
1118          * set in devicetree. It is assumed the voltage values are known if that
1119          * property is set since it is useless otherwise. If voltages are not
1120          * known, just let the EM registration fail with an error to alert the
1121          * user about the inconsistent configuration.
1122          */
1123         ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1124         of_node_put(np);
1125         if (ret || !cap)
1126                 return;
1127
1128         em_register_perf_domain(cpus, nr_opp, &em_cb);
1129 }
1130 EXPORT_SYMBOL_GPL(dev_pm_opp_of_register_em);