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         struct device_node *required_np;
  99
 100         required_np = of_parse_phandle(np, "required-opps", index);
 101         if (unlikely(!required_np)) {
 102                 pr_err("%s: Unable to parse required-opps: %pOF, index: %d\n",
 103                        __func__, np, index);
 104         }
 105
 106         return required_np;
 107 }
 108
 109 /* The caller must call dev_pm_opp_put_opp_table() after the table is used */
 110 static struct opp_table *_find_table_of_opp_np(struct device_node *opp_np)
 111 {
 112         struct opp_table *opp_table;
 113         struct device_node *opp_table_np;
 114
 115         lockdep_assert_held(&opp_table_lock);
 116
 117         opp_table_np = of_get_parent(opp_np);
 118         if (!opp_table_np)
 119                 goto err;
 120
 121         /* It is safe to put the node now as all we need now is its address */
 122         of_node_put(opp_table_np);
 123
 124         list_for_each_entry(opp_table, &opp_tables, node) {
 125                 if (opp_table_np == opp_table->np) {
 126                         _get_opp_table_kref(opp_table);
 127                         return opp_table;
 128                 }
 129         }
 130
 131 err:
 132         return ERR_PTR(-ENODEV);
 133 }
 134
 135 /* Free resources previously acquired by _opp_table_alloc_required_tables() */
 136 static void _opp_table_free_required_tables(struct opp_table *opp_table)
 137 {
 138         struct opp_table **required_opp_tables = opp_table->required_opp_tables;
 139         int i;
 140
 141         if (!required_opp_tables)
 142                 return;
 143
 144         for (i = 0; i < opp_table->required_opp_count; i++) {
 145                 if (IS_ERR_OR_NULL(required_opp_tables[i]))
 146                         break;
 147
 148                 dev_pm_opp_put_opp_table(required_opp_tables[i]);
 149         }
 150
 151         kfree(required_opp_tables);
 152
 153         opp_table->required_opp_count = 0;
 154         opp_table->required_opp_tables = NULL;
 155 }
 156
 157 /*
 158  * Populate all devices and opp tables which are part of "required-opps" list.
 159  * Checking only the first OPP node should be enough.
 160  */
 161 static void _opp_table_alloc_required_tables(struct opp_table *opp_table,
 162                                              struct device *dev,
 163                                              struct device_node *opp_np)
 164 {
 165         struct opp_table **required_opp_tables;
 166         struct device_node *required_np, *np;
 167         int count, i;
 168
 169         /* Traversing the first OPP node is all we need */
 170         np = of_get_next_available_child(opp_np, NULL);
 171         if (!np) {
 172                 dev_err(dev, "Empty OPP table\n");
 173                 return;
 174         }
 175
 176         count = of_count_phandle_with_args(np, "required-opps", NULL);
 177         if (!count)
 178                 goto put_np;
 179
 180         required_opp_tables = kcalloc(count, sizeof(*required_opp_tables),
 181                                       GFP_KERNEL);
 182         if (!required_opp_tables)
 183                 goto put_np;
 184
 185         opp_table->required_opp_tables = required_opp_tables;
 186         opp_table->required_opp_count = count;
 187
 188         for (i = 0; i < count; i++) {
 189                 required_np = of_parse_required_opp(np, i);
 190                 if (!required_np)
 191                         goto free_required_tables;
 192
 193                 required_opp_tables[i] = _find_table_of_opp_np(required_np);
 194                 of_node_put(required_np);
 195
 196                 if (IS_ERR(required_opp_tables[i]))
 197                         goto free_required_tables;
 198
 199                 /*
 200                  * We only support genpd's OPPs in the "required-opps" for now,
 201                  * as we don't know how much about other cases. Error out if the
 202                  * required OPP doesn't belong to a genpd.
 203                  */
 204                 if (!required_opp_tables[i]->is_genpd) {
 205                         dev_err(dev, "required-opp doesn't belong to genpd: %pOF\n",
 206                                 required_np);
 207                         goto free_required_tables;
 208                 }
 209         }
 210
 211         goto put_np;
 212
 213 free_required_tables:
 214         _opp_table_free_required_tables(opp_table);
 215 put_np:
 216         of_node_put(np);
 217 }
 218
 219 void _of_init_opp_table(struct opp_table *opp_table, struct device *dev,
 220                         int index)
 221 {
 222         struct device_node *np, *opp_np;
 223         u32 val;
 224
 225         /*
 226          * Only required for backward compatibility with v1 bindings, but isn't
 227          * harmful for other cases. And so we do it unconditionally.
 228          */
 229         np = of_node_get(dev->of_node);
 230         if (!np)
 231                 return;
 232
 233         if (!of_property_read_u32(np, "clock-latency", &val))
 234                 opp_table->clock_latency_ns_max = val;
 235         of_property_read_u32(np, "voltage-tolerance",
 236                              &opp_table->voltage_tolerance_v1);
 237
 238         if (of_find_property(np, "#power-domain-cells", NULL))
 239                 opp_table->is_genpd = true;
 240
 241         /* Get OPP table node */
 242         opp_np = _opp_of_get_opp_desc_node(np, index);
 243         of_node_put(np);
 244
 245         if (!opp_np)
 246                 return;
 247
 248         if (of_property_read_bool(opp_np, "opp-shared"))
 249                 opp_table->shared_opp = OPP_TABLE_ACCESS_SHARED;
 250         else
 251                 opp_table->shared_opp = OPP_TABLE_ACCESS_EXCLUSIVE;
 252
 253         opp_table->np = opp_np;
 254
 255         _opp_table_alloc_required_tables(opp_table, dev, opp_np);
 256         of_node_put(opp_np);
 257 }
 258
 259 void _of_clear_opp_table(struct opp_table *opp_table)
 260 {
 261         _opp_table_free_required_tables(opp_table);
 262 }
 263
 264 /*
 265  * Release all resources previously acquired with a call to
 266  * _of_opp_alloc_required_opps().
 267  */
 268 void _of_opp_free_required_opps(struct opp_table *opp_table,
 269                                 struct dev_pm_opp *opp)
 270 {
 271         struct dev_pm_opp **required_opps = opp->required_opps;
 272         int i;
 273
 274         if (!required_opps)
 275                 return;
 276
 277         for (i = 0; i < opp_table->required_opp_count; i++) {
 278                 if (!required_opps[i])
 279                         break;
 280
 281                 /* Put the reference back */
 282                 dev_pm_opp_put(required_opps[i]);
 283         }
 284
 285         kfree(required_opps);
 286         opp->required_opps = NULL;
 287 }
 288
 289 /* Populate all required OPPs which are part of "required-opps" list */
 290 static int _of_opp_alloc_required_opps(struct opp_table *opp_table,
 291                                        struct dev_pm_opp *opp)
 292 {
 293         struct dev_pm_opp **required_opps;
 294         struct opp_table *required_table;
 295         struct device_node *np;
 296         int i, ret, count = opp_table->required_opp_count;
 297
 298         if (!count)
 299                 return 0;
 300
 301         required_opps = kcalloc(count, sizeof(*required_opps), GFP_KERNEL);
 302         if (!required_opps)
 303                 return -ENOMEM;
 304
 305         opp->required_opps = required_opps;
 306
 307         for (i = 0; i < count; i++) {
 308                 required_table = opp_table->required_opp_tables[i];
 309
 310                 np = of_parse_required_opp(opp->np, i);
 311                 if (unlikely(!np)) {
 312                         ret = -ENODEV;
 313                         goto free_required_opps;
 314                 }
 315
 316                 required_opps[i] = _find_opp_of_np(required_table, np);
 317                 of_node_put(np);
 318
 319                 if (!required_opps[i]) {
 320                         pr_err("%s: Unable to find required OPP node: %pOF (%d)\n",
 321                                __func__, opp->np, i);
 322                         ret = -ENODEV;
 323                         goto free_required_opps;
 324                 }
 325         }
 326
 327         return 0;
 328
 329 free_required_opps:
 330         _of_opp_free_required_opps(opp_table, opp);
 331
 332         return ret;
 333 }
 334
 335 static int _bandwidth_supported(struct device *dev, struct opp_table *opp_table)
 336 {
 337         struct device_node *np, *opp_np;
 338         struct property *prop;
 339
 340         if (!opp_table) {
 341                 np = of_node_get(dev->of_node);
 342                 if (!np)
 343                         return -ENODEV;
 344
 345                 opp_np = _opp_of_get_opp_desc_node(np, 0);
 346                 of_node_put(np);
 347         } else {
 348                 opp_np = of_node_get(opp_table->np);
 349         }
 350
 351         /* Lets not fail in case we are parsing opp-v1 bindings */
 352         if (!opp_np)
 353                 return 0;
 354
 355         /* Checking only first OPP is sufficient */
 356         np = of_get_next_available_child(opp_np, NULL);
 357         if (!np) {
 358                 dev_err(dev, "OPP table empty\n");
 359                 return -EINVAL;
 360         }
 361         of_node_put(opp_np);
 362
 363         prop = of_find_property(np, "opp-peak-kBps", NULL);
 364         of_node_put(np);
 365
 366         if (!prop || !prop->length)
 367                 return 0;
 368
 369         return 1;
 370 }
 371
 372 int dev_pm_opp_of_find_icc_paths(struct device *dev,
 373                                  struct opp_table *opp_table)
 374 {
 375         struct device_node *np;
 376         int ret, i, count, num_paths;
 377         struct icc_path **paths;
 378
 379         ret = _bandwidth_supported(dev, opp_table);
 380         if (ret <= 0)
 381                 return ret;
 382
 383         ret = 0;
 384
 385         np = of_node_get(dev->of_node);
 386         if (!np)
 387                 return 0;
 388
 389         count = of_count_phandle_with_args(np, "interconnects",
 390                                            "#interconnect-cells");
 391         of_node_put(np);
 392         if (count < 0)
 393                 return 0;
 394
 395         /* two phandles when #interconnect-cells = <1> */
 396         if (count % 2) {
 397                 dev_err(dev, "%s: Invalid interconnects values\n", __func__);
 398                 return -EINVAL;
 399         }
 400
 401         num_paths = count / 2;
 402         paths = kcalloc(num_paths, sizeof(*paths), GFP_KERNEL);
 403         if (!paths)
 404                 return -ENOMEM;
 405
 406         for (i = 0; i < num_paths; i++) {
 407                 paths[i] = of_icc_get_by_index(dev, i);
 408                 if (IS_ERR(paths[i])) {
 409                         ret = PTR_ERR(paths[i]);
 410                         if (ret != -EPROBE_DEFER) {
 411                                 dev_err(dev, "%s: Unable to get path%d: %d\n",
 412                                         __func__, i, ret);
 413                         }
 414                         goto err;
 415                 }
 416         }
 417
 418         if (opp_table) {
 419                 opp_table->paths = paths;
 420                 opp_table->path_count = num_paths;
 421                 return 0;
 422         }
 423
 424 err:
 425         while (i--)
 426                 icc_put(paths[i]);
 427
 428         kfree(paths);
 429
 430         return ret;
 431 }
 432 EXPORT_SYMBOL_GPL(dev_pm_opp_of_find_icc_paths);
 433
 434 static bool _opp_is_supported(struct device *dev, struct opp_table *opp_table,
 435                               struct device_node *np)
 436 {
 437         unsigned int count = opp_table->supported_hw_count;
 438         u32 version;
 439         int ret;
 440
 441         if (!opp_table->supported_hw) {
 442                 /*
 443                  * In the case that no supported_hw has been set by the
 444                  * platform but there is an opp-supported-hw value set for
 445                  * an OPP then the OPP should not be enabled as there is
 446                  * no way to see if the hardware supports it.
 447                  */
 448                 if (of_find_property(np, "opp-supported-hw", NULL))
 449                         return false;
 450                 else
 451                         return true;
 452         }
 453
 454         while (count--) {
 455                 ret = of_property_read_u32_index(np, "opp-supported-hw", count,
 456                                                  &version);
 457                 if (ret) {
 458                         dev_warn(dev, "%s: failed to read opp-supported-hw property at index %d: %d\n",
 459                                  __func__, count, ret);
 460                         return false;
 461                 }
 462
 463                 /* Both of these are bitwise masks of the versions */
 464                 if (!(version & opp_table->supported_hw[count]))
 465                         return false;
 466         }
 467
 468         return true;
 469 }
 470
 471 static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,
 472                               struct opp_table *opp_table)
 473 {
 474         u32 *microvolt, *microamp = NULL;
 475         int supplies = opp_table->regulator_count, vcount, icount, ret, i, j;
 476         struct property *prop = NULL;
 477         char name[NAME_MAX];
 478
 479         /* Search for "opp-microvolt-<name>" */
 480         if (opp_table->prop_name) {
 481                 snprintf(name, sizeof(name), "opp-microvolt-%s",
 482                          opp_table->prop_name);
 483                 prop = of_find_property(opp->np, name, NULL);
 484         }
 485
 486         if (!prop) {
 487                 /* Search for "opp-microvolt" */
 488                 sprintf(name, "opp-microvolt");
 489                 prop = of_find_property(opp->np, name, NULL);
 490
 491                 /* Missing property isn't a problem, but an invalid entry is */
 492                 if (!prop) {
 493                         if (unlikely(supplies == -1)) {
 494                                 /* Initialize regulator_count */
 495                                 opp_table->regulator_count = 0;
 496                                 return 0;
 497                         }
 498
 499                         if (!supplies)
 500                                 return 0;
 501
 502                         dev_err(dev, "%s: opp-microvolt missing although OPP managing regulators\n",
 503                                 __func__);
 504                         return -EINVAL;
 505                 }
 506         }
 507
 508         if (unlikely(supplies == -1)) {
 509                 /* Initialize regulator_count */
 510                 supplies = opp_table->regulator_count = 1;
 511         } else if (unlikely(!supplies)) {
 512                 dev_err(dev, "%s: opp-microvolt wasn't expected\n", __func__);
 513                 return -EINVAL;
 514         }
 515
 516         vcount = of_property_count_u32_elems(opp->np, name);
 517         if (vcount < 0) {
 518                 dev_err(dev, "%s: Invalid %s property (%d)\n",
 519                         __func__, name, vcount);
 520                 return vcount;
 521         }
 522
 523         /* There can be one or three elements per supply */
 524         if (vcount != supplies && vcount != supplies * 3) {
 525                 dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
 526                         __func__, name, vcount, supplies);
 527                 return -EINVAL;
 528         }
 529
 530         microvolt = kmalloc_array(vcount, sizeof(*microvolt), GFP_KERNEL);
 531         if (!microvolt)
 532                 return -ENOMEM;
 533
 534         ret = of_property_read_u32_array(opp->np, name, microvolt, vcount);
 535         if (ret) {
 536                 dev_err(dev, "%s: error parsing %s: %d\n", __func__, name, ret);
 537                 ret = -EINVAL;
 538                 goto free_microvolt;
 539         }
 540
 541         /* Search for "opp-microamp-<name>" */
 542         prop = NULL;
 543         if (opp_table->prop_name) {
 544                 snprintf(name, sizeof(name), "opp-microamp-%s",
 545                          opp_table->prop_name);
 546                 prop = of_find_property(opp->np, name, NULL);
 547         }
 548
 549         if (!prop) {
 550                 /* Search for "opp-microamp" */
 551                 sprintf(name, "opp-microamp");
 552                 prop = of_find_property(opp->np, name, NULL);
 553         }
 554
 555         if (prop) {
 556                 icount = of_property_count_u32_elems(opp->np, name);
 557                 if (icount < 0) {
 558                         dev_err(dev, "%s: Invalid %s property (%d)\n", __func__,
 559                                 name, icount);
 560                         ret = icount;
 561                         goto free_microvolt;
 562                 }
 563
 564                 if (icount != supplies) {
 565                         dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
 566                                 __func__, name, icount, supplies);
 567                         ret = -EINVAL;
 568                         goto free_microvolt;
 569                 }
 570
 571                 microamp = kmalloc_array(icount, sizeof(*microamp), GFP_KERNEL);
 572                 if (!microamp) {
 573                         ret = -EINVAL;
 574                         goto free_microvolt;
 575                 }
 576
 577                 ret = of_property_read_u32_array(opp->np, name, microamp,
 578                                                  icount);
 579                 if (ret) {
 580                         dev_err(dev, "%s: error parsing %s: %d\n", __func__,
 581                                 name, ret);
 582                         ret = -EINVAL;
 583                         goto free_microamp;
 584                 }
 585         }
 586
 587         for (i = 0, j = 0; i < supplies; i++) {
 588                 opp->supplies[i].u_volt = microvolt[j++];
 589
 590                 if (vcount == supplies) {
 591                         opp->supplies[i].u_volt_min = opp->supplies[i].u_volt;
 592                         opp->supplies[i].u_volt_max = opp->supplies[i].u_volt;
 593                 } else {
 594                         opp->supplies[i].u_volt_min = microvolt[j++];
 595                         opp->supplies[i].u_volt_max = microvolt[j++];
 596                 }
 597
 598                 if (microamp)
 599                         opp->supplies[i].u_amp = microamp[i];
 600         }
 601
 602 free_microamp:
 603         kfree(microamp);
 604 free_microvolt:
 605         kfree(microvolt);
 606
 607         return ret;
 608 }
 609
 610 /**
 611  * dev_pm_opp_of_remove_table() - Free OPP table entries created from static DT
 612  *                                entries
 613  * @dev:        device pointer used to lookup OPP table.
 614  *
 615  * Free OPPs created using static entries present in DT.
 616  */
 617 void dev_pm_opp_of_remove_table(struct device *dev)
 618 {
 619         _dev_pm_opp_find_and_remove_table(dev);
 620 }
 621 EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table);
 622
 623 static int _read_bw(struct dev_pm_opp *new_opp, struct opp_table *table,
 624                     struct device_node *np, bool peak)
 625 {
 626         const char *name = peak ? "opp-peak-kBps" : "opp-avg-kBps";
 627         struct property *prop;
 628         int i, count, ret;
 629         u32 *bw;
 630
 631         prop = of_find_property(np, name, NULL);
 632         if (!prop)
 633                 return -ENODEV;
 634
 635         count = prop->length / sizeof(u32);
 636         if (table->path_count != count) {
 637                 pr_err("%s: Mismatch between %s and paths (%d %d)\n",
 638                                 __func__, name, count, table->path_count);
 639                 return -EINVAL;
 640         }
 641
 642         bw = kmalloc_array(count, sizeof(*bw), GFP_KERNEL);
 643         if (!bw)
 644                 return -ENOMEM;
 645
 646         ret = of_property_read_u32_array(np, name, bw, count);
 647         if (ret) {
 648                 pr_err("%s: Error parsing %s: %d\n", __func__, name, ret);
 649                 goto out;
 650         }
 651
 652         for (i = 0; i < count; i++) {
 653                 if (peak)
 654                         new_opp->bandwidth[i].peak = kBps_to_icc(bw[i]);
 655                 else
 656                         new_opp->bandwidth[i].avg = kBps_to_icc(bw[i]);
 657         }
 658
 659 out:
 660         kfree(bw);
 661         return ret;
 662 }
 663
 664 static int _read_opp_key(struct dev_pm_opp *new_opp, struct opp_table *table,
 665                          struct device_node *np, bool *rate_not_available)
 666 {
 667         bool found = false;
 668         u64 rate;
 669         int ret;
 670
 671         ret = of_property_read_u64(np, "opp-hz", &rate);
 672         if (!ret) {
 673                 /*
 674                  * Rate is defined as an unsigned long in clk API, and so
 675                  * casting explicitly to its type. Must be fixed once rate is 64
 676                  * bit guaranteed in clk API.
 677                  */
 678                 new_opp->rate = (unsigned long)rate;
 679                 found = true;
 680         }
 681         *rate_not_available = !!ret;
 682
 683         /*
 684          * Bandwidth consists of peak and average (optional) values:
 685          * opp-peak-kBps = <path1_value path2_value>;
 686          * opp-avg-kBps = <path1_value path2_value>;
 687          */
 688         ret = _read_bw(new_opp, table, np, true);
 689         if (!ret) {
 690                 found = true;
 691                 ret = _read_bw(new_opp, table, np, false);
 692         }
 693
 694         /* The properties were found but we failed to parse them */
 695         if (ret && ret != -ENODEV)
 696                 return ret;
 697
 698         if (!of_property_read_u32(np, "opp-level", &new_opp->level))
 699                 found = true;
 700
 701         if (found)
 702                 return 0;
 703
 704         return ret;
 705 }
 706
 707 /**
 708  * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings)
 709  * @opp_table:  OPP table
 710  * @dev:        device for which we do this operation
 711  * @np:         device node
 712  *
 713  * This function adds an opp definition to the opp table and returns status. The
 714  * opp can be controlled using dev_pm_opp_enable/disable functions and may be
 715  * removed by dev_pm_opp_remove.
 716  *
 717  * Return:
 718  * Valid OPP pointer:
 719  *              On success
 720  * NULL:
 721  *              Duplicate OPPs (both freq and volt are same) and opp->available
 722  *              OR if the OPP is not supported by hardware.
 723  * ERR_PTR(-EEXIST):
 724  *              Freq are same and volt are different OR
 725  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 726  * ERR_PTR(-ENOMEM):
 727  *              Memory allocation failure
 728  * ERR_PTR(-EINVAL):
 729  *              Failed parsing the OPP node
 730  */
 731 static struct dev_pm_opp *_opp_add_static_v2(struct opp_table *opp_table,
 732                 struct device *dev, struct device_node *np)
 733 {
 734         struct dev_pm_opp *new_opp;
 735         u64 rate = 0;
 736         u32 val;
 737         int ret;
 738         bool rate_not_available = false;
 739
 740         new_opp = _opp_allocate(opp_table);
 741         if (!new_opp)
 742                 return ERR_PTR(-ENOMEM);
 743
 744         ret = _read_opp_key(new_opp, opp_table, np, &rate_not_available);
 745         if (ret < 0 && !opp_table->is_genpd) {
 746                 dev_err(dev, "%s: opp key field not found\n", __func__);
 747                 goto free_opp;
 748         }
 749
 750         /* Check if the OPP supports hardware's hierarchy of versions or not */
 751         if (!_opp_is_supported(dev, opp_table, np)) {
 752                 dev_dbg(dev, "OPP not supported by hardware: %llu\n", rate);
 753                 goto free_opp;
 754         }
 755
 756         new_opp->turbo = of_property_read_bool(np, "turbo-mode");
 757
 758         new_opp->np = np;
 759         new_opp->dynamic = false;
 760         new_opp->available = true;
 761
 762         ret = _of_opp_alloc_required_opps(opp_table, new_opp);
 763         if (ret)
 764                 goto free_opp;
 765
 766         if (!of_property_read_u32(np, "clock-latency-ns", &val))
 767                 new_opp->clock_latency_ns = val;
 768
 769         ret = opp_parse_supplies(new_opp, dev, opp_table);
 770         if (ret)
 771                 goto free_required_opps;
 772
 773         if (opp_table->is_genpd)
 774                 new_opp->pstate = pm_genpd_opp_to_performance_state(dev, new_opp);
 775
 776         ret = _opp_add(dev, new_opp, opp_table, rate_not_available);
 777         if (ret) {
 778                 /* Don't return error for duplicate OPPs */
 779                 if (ret == -EBUSY)
 780                         ret = 0;
 781                 goto free_required_opps;
 782         }
 783
 784         /* OPP to select on device suspend */
 785         if (of_property_read_bool(np, "opp-suspend")) {
 786                 if (opp_table->suspend_opp) {
 787                         /* Pick the OPP with higher rate as suspend OPP */
 788                         if (new_opp->rate > opp_table->suspend_opp->rate) {
 789                                 opp_table->suspend_opp->suspend = false;
 790                                 new_opp->suspend = true;
 791                                 opp_table->suspend_opp = new_opp;
 792                         }
 793                 } else {
 794                         new_opp->suspend = true;
 795                         opp_table->suspend_opp = new_opp;
 796                 }
 797         }
 798
 799         if (new_opp->clock_latency_ns > opp_table->clock_latency_ns_max)
 800                 opp_table->clock_latency_ns_max = new_opp->clock_latency_ns;
 801
 802         pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu\n",
 803                  __func__, new_opp->turbo, new_opp->rate,
 804                  new_opp->supplies[0].u_volt, new_opp->supplies[0].u_volt_min,
 805                  new_opp->supplies[0].u_volt_max, new_opp->clock_latency_ns);
 806
 807         /*
 808          * Notify the changes in the availability of the operable
 809          * frequency/voltage list.
 810          */
 811         blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ADD, new_opp);
 812         return new_opp;
 813
 814 free_required_opps:
 815         _of_opp_free_required_opps(opp_table, new_opp);
 816 free_opp:
 817         _opp_free(new_opp);
 818
 819         return ERR_PTR(ret);
 820 }
 821
 822 /* Initializes OPP tables based on new bindings */
 823 static int _of_add_opp_table_v2(struct device *dev, struct opp_table *opp_table)
 824 {
 825         struct device_node *np;
 826         int ret, count = 0, pstate_count = 0;
 827         struct dev_pm_opp *opp;
 828
 829         /* OPP table is already initialized for the device */
 830         mutex_lock(&opp_table->lock);
 831         if (opp_table->parsed_static_opps) {
 832                 opp_table->parsed_static_opps++;
 833                 mutex_unlock(&opp_table->lock);
 834                 return 0;
 835         }
 836
 837         opp_table->parsed_static_opps = 1;
 838         mutex_unlock(&opp_table->lock);
 839
 840         /* We have opp-table node now, iterate over it and add OPPs */
 841         for_each_available_child_of_node(opp_table->np, np) {
 842                 opp = _opp_add_static_v2(opp_table, dev, np);
 843                 if (IS_ERR(opp)) {
 844                         ret = PTR_ERR(opp);
 845                         dev_err(dev, "%s: Failed to add OPP, %d\n", __func__,
 846                                 ret);
 847                         of_node_put(np);
 848                         goto remove_static_opp;
 849                 } else if (opp) {
 850                         count++;
 851                 }
 852         }
 853
 854         /* There should be one of more OPP defined */
 855         if (WARN_ON(!count)) {
 856                 ret = -ENOENT;
 857                 goto remove_static_opp;
 858         }
 859
 860         list_for_each_entry(opp, &opp_table->opp_list, node)
 861                 pstate_count += !!opp->pstate;
 862
 863         /* Either all or none of the nodes shall have performance state set */
 864         if (pstate_count && pstate_count != count) {
 865                 dev_err(dev, "Not all nodes have performance state set (%d: %d)\n",
 866                         count, pstate_count);
 867                 ret = -ENOENT;
 868                 goto remove_static_opp;
 869         }
 870
 871         if (pstate_count)
 872                 opp_table->genpd_performance_state = true;
 873
 874         return 0;
 875
 876 remove_static_opp:
 877         _opp_remove_all_static(opp_table);
 878
 879         return ret;
 880 }
 881
 882 /* Initializes OPP tables based on old-deprecated bindings */
 883 static int _of_add_opp_table_v1(struct device *dev, struct opp_table *opp_table)
 884 {
 885         const struct property *prop;
 886         const __be32 *val;
 887         int nr, ret = 0;
 888
 889         prop = of_find_property(dev->of_node, "operating-points", NULL);
 890         if (!prop)
 891                 return -ENODEV;
 892         if (!prop->value)
 893                 return -ENODATA;
 894
 895         /*
 896          * Each OPP is a set of tuples consisting of frequency and
 897          * voltage like <freq-kHz vol-uV>.
 898          */
 899         nr = prop->length / sizeof(u32);
 900         if (nr % 2) {
 901                 dev_err(dev, "%s: Invalid OPP table\n", __func__);
 902                 return -EINVAL;
 903         }
 904
 905         val = prop->value;
 906         while (nr) {
 907                 unsigned long freq = be32_to_cpup(val++) * 1000;
 908                 unsigned long volt = be32_to_cpup(val++);
 909
 910                 ret = _opp_add_v1(opp_table, dev, freq, volt, false);
 911                 if (ret) {
 912                         dev_err(dev, "%s: Failed to add OPP %ld (%d)\n",
 913                                 __func__, freq, ret);
 914                         _opp_remove_all_static(opp_table);
 915                         return ret;
 916                 }
 917                 nr -= 2;
 918         }
 919
 920         return ret;
 921 }
 922
 923 /**
 924  * dev_pm_opp_of_add_table() - Initialize opp table from device tree
 925  * @dev:        device pointer used to lookup OPP table.
 926  *
 927  * Register the initial OPP table with the OPP library for given device.
 928  *
 929  * Return:
 930  * 0            On success OR
 931  *              Duplicate OPPs (both freq and volt are same) and opp->available
 932  * -EEXIST      Freq are same and volt are different OR
 933  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 934  * -ENOMEM      Memory allocation failure
 935  * -ENODEV      when 'operating-points' property is not found or is invalid data
 936  *              in device node.
 937  * -ENODATA     when empty 'operating-points' property is found
 938  * -EINVAL      when invalid entries are found in opp-v2 table
 939  */
 940 int dev_pm_opp_of_add_table(struct device *dev)
 941 {
 942         struct opp_table *opp_table;
 943         int ret;
 944
 945         opp_table = dev_pm_opp_get_opp_table_indexed(dev, 0);
 946         if (!opp_table)
 947                 return -ENOMEM;
 948
 949         /*
 950          * OPPs have two version of bindings now. Also try the old (v1)
 951          * bindings for backward compatibility with older dtbs.
 952          */
 953         if (opp_table->np)
 954                 ret = _of_add_opp_table_v2(dev, opp_table);
 955         else
 956                 ret = _of_add_opp_table_v1(dev, opp_table);
 957
 958         if (ret)
 959                 dev_pm_opp_put_opp_table(opp_table);
 960
 961         return ret;
 962 }
 963 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table);
 964
 965 /**
 966  * dev_pm_opp_of_add_table_indexed() - Initialize indexed opp table from device tree
 967  * @dev:        device pointer used to lookup OPP table.
 968  * @index:      Index number.
 969  *
 970  * Register the initial OPP table with the OPP library for given device only
 971  * using the "operating-points-v2" property.
 972  *
 973  * Return:
 974  * 0            On success OR
 975  *              Duplicate OPPs (both freq and volt are same) and opp->available
 976  * -EEXIST      Freq are same and volt are different OR
 977  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 978  * -ENOMEM      Memory allocation failure
 979  * -ENODEV      when 'operating-points' property is not found or is invalid data
 980  *              in device node.
 981  * -ENODATA     when empty 'operating-points' property is found
 982  * -EINVAL      when invalid entries are found in opp-v2 table
 983  */
 984 int dev_pm_opp_of_add_table_indexed(struct device *dev, int index)
 985 {
 986         struct opp_table *opp_table;
 987         int ret, count;
 988
 989         if (index) {
 990                 /*
 991                  * If only one phandle is present, then the same OPP table
 992                  * applies for all index requests.
 993                  */
 994                 count = of_count_phandle_with_args(dev->of_node,
 995                                                    "operating-points-v2", NULL);
 996                 if (count == 1)
 997                         index = 0;
 998         }
 999
1000         opp_table = dev_pm_opp_get_opp_table_indexed(dev, index);
1001         if (!opp_table)
1002                 return -ENOMEM;
1003
1004         ret = _of_add_opp_table_v2(dev, opp_table);
1005         if (ret)
1006                 dev_pm_opp_put_opp_table(opp_table);
1007
1008         return ret;
1009 }
1010 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table_indexed);
1011
1012 /* CPU device specific helpers */
1013
1014 /**
1015  * dev_pm_opp_of_cpumask_remove_table() - Removes OPP table for @cpumask
1016  * @cpumask:    cpumask for which OPP table needs to be removed
1017  *
1018  * This removes the OPP tables for CPUs present in the @cpumask.
1019  * This should be used only to remove static entries created from DT.
1020  */
1021 void dev_pm_opp_of_cpumask_remove_table(const struct cpumask *cpumask)
1022 {
1023         _dev_pm_opp_cpumask_remove_table(cpumask, -1);
1024 }
1025 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_remove_table);
1026
1027 /**
1028  * dev_pm_opp_of_cpumask_add_table() - Adds OPP table for @cpumask
1029  * @cpumask:    cpumask for which OPP table needs to be added.
1030  *
1031  * This adds the OPP tables for CPUs present in the @cpumask.
1032  */
1033 int dev_pm_opp_of_cpumask_add_table(const struct cpumask *cpumask)
1034 {
1035         struct device *cpu_dev;
1036         int cpu, ret;
1037
1038         if (WARN_ON(cpumask_empty(cpumask)))
1039                 return -ENODEV;
1040
1041         for_each_cpu(cpu, cpumask) {
1042                 cpu_dev = get_cpu_device(cpu);
1043                 if (!cpu_dev) {
1044                         pr_err("%s: failed to get cpu%d device\n", __func__,
1045                                cpu);
1046                         ret = -ENODEV;
1047                         goto remove_table;
1048                 }
1049
1050                 ret = dev_pm_opp_of_add_table(cpu_dev);
1051                 if (ret) {
1052                         /*
1053                          * OPP may get registered dynamically, don't print error
1054                          * message here.
1055                          */
1056                         pr_debug("%s: couldn't find opp table for cpu:%d, %d\n",
1057                                  __func__, cpu, ret);
1058
1059                         goto remove_table;
1060                 }
1061         }
1062
1063         return 0;
1064
1065 remove_table:
1066         /* Free all other OPPs */
1067         _dev_pm_opp_cpumask_remove_table(cpumask, cpu);
1068
1069         return ret;
1070 }
1071 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_add_table);
1072
1073 /*
1074  * Works only for OPP v2 bindings.
1075  *
1076  * Returns -ENOENT if operating-points-v2 bindings aren't supported.
1077  */
1078 /**
1079  * dev_pm_opp_of_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with
1080  *                                    @cpu_dev using operating-points-v2
1081  *                                    bindings.
1082  *
1083  * @cpu_dev:    CPU device for which we do this operation
1084  * @cpumask:    cpumask to update with information of sharing CPUs
1085  *
1086  * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev.
1087  *
1088  * Returns -ENOENT if operating-points-v2 isn't present for @cpu_dev.
1089  */
1090 int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev,
1091                                    struct cpumask *cpumask)
1092 {
1093         struct device_node *np, *tmp_np, *cpu_np;
1094         int cpu, ret = 0;
1095
1096         /* Get OPP descriptor node */
1097         np = dev_pm_opp_of_get_opp_desc_node(cpu_dev);
1098         if (!np) {
1099                 dev_dbg(cpu_dev, "%s: Couldn't find opp node.\n", __func__);
1100                 return -ENOENT;
1101         }
1102
1103         cpumask_set_cpu(cpu_dev->id, cpumask);
1104
1105         /* OPPs are shared ? */
1106         if (!of_property_read_bool(np, "opp-shared"))
1107                 goto put_cpu_node;
1108
1109         for_each_possible_cpu(cpu) {
1110                 if (cpu == cpu_dev->id)
1111                         continue;
1112
1113                 cpu_np = of_cpu_device_node_get(cpu);
1114                 if (!cpu_np) {
1115                         dev_err(cpu_dev, "%s: failed to get cpu%d node\n",
1116                                 __func__, cpu);
1117                         ret = -ENOENT;
1118                         goto put_cpu_node;
1119                 }
1120
1121                 /* Get OPP descriptor node */
1122                 tmp_np = _opp_of_get_opp_desc_node(cpu_np, 0);
1123                 of_node_put(cpu_np);
1124                 if (!tmp_np) {
1125                         pr_err("%pOF: Couldn't find opp node\n", cpu_np);
1126                         ret = -ENOENT;
1127                         goto put_cpu_node;
1128                 }
1129
1130                 /* CPUs are sharing opp node */
1131                 if (np == tmp_np)
1132                         cpumask_set_cpu(cpu, cpumask);
1133
1134                 of_node_put(tmp_np);
1135         }
1136
1137 put_cpu_node:
1138         of_node_put(np);
1139         return ret;
1140 }
1141 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus);
1142
1143 /**
1144  * of_get_required_opp_performance_state() - Search for required OPP and return its performance state.
1145  * @np: Node that contains the "required-opps" property.
1146  * @index: Index of the phandle to parse.
1147  *
1148  * Returns the performance state of the OPP pointed out by the "required-opps"
1149  * property at @index in @np.
1150  *
1151  * Return: Zero or positive performance state on success, otherwise negative
1152  * value on errors.
1153  */
1154 int of_get_required_opp_performance_state(struct device_node *np, int index)
1155 {
1156         struct dev_pm_opp *opp;
1157         struct device_node *required_np;
1158         struct opp_table *opp_table;
1159         int pstate = -EINVAL;
1160
1161         required_np = of_parse_required_opp(np, index);
1162         if (!required_np)
1163                 return -EINVAL;
1164
1165         opp_table = _find_table_of_opp_np(required_np);
1166         if (IS_ERR(opp_table)) {
1167                 pr_err("%s: Failed to find required OPP table %pOF: %ld\n",
1168                        __func__, np, PTR_ERR(opp_table));
1169                 goto put_required_np;
1170         }
1171
1172         opp = _find_opp_of_np(opp_table, required_np);
1173         if (opp) {
1174                 pstate = opp->pstate;
1175                 dev_pm_opp_put(opp);
1176         }
1177
1178         dev_pm_opp_put_opp_table(opp_table);
1179
1180 put_required_np:
1181         of_node_put(required_np);
1182
1183         return pstate;
1184 }
1185 EXPORT_SYMBOL_GPL(of_get_required_opp_performance_state);
1186
1187 /**
1188  * dev_pm_opp_get_of_node() - Gets the DT node corresponding to an opp
1189  * @opp:        opp for which DT node has to be returned for
1190  *
1191  * Return: DT node corresponding to the opp, else 0 on success.
1192  *
1193  * The caller needs to put the node with of_node_put() after using it.
1194  */
1195 struct device_node *dev_pm_opp_get_of_node(struct dev_pm_opp *opp)
1196 {
1197         if (IS_ERR_OR_NULL(opp)) {
1198                 pr_err("%s: Invalid parameters\n", __func__);
1199                 return NULL;
1200         }
1201
1202         return of_node_get(opp->np);
1203 }
1204 EXPORT_SYMBOL_GPL(dev_pm_opp_get_of_node);
1205
1206 /*
1207  * Callback function provided to the Energy Model framework upon registration.
1208  * This computes the power estimated by @CPU at @kHz if it is the frequency
1209  * of an existing OPP, or at the frequency of the first OPP above @kHz otherwise
1210  * (see dev_pm_opp_find_freq_ceil()). This function updates @kHz to the ceiled
1211  * frequency and @mW to the associated power. The power is estimated as
1212  * P = C * V^2 * f with C being the CPU's capacitance and V and f respectively
1213  * the voltage and frequency of the OPP.
1214  *
1215  * Returns -ENODEV if the CPU device cannot be found, -EINVAL if the power
1216  * calculation failed because of missing parameters, 0 otherwise.
1217  */
1218 static int __maybe_unused _get_cpu_power(unsigned long *mW, unsigned long *kHz,
1219                                          int cpu)
1220 {
1221         struct device *cpu_dev;
1222         struct dev_pm_opp *opp;
1223         struct device_node *np;
1224         unsigned long mV, Hz;
1225         u32 cap;
1226         u64 tmp;
1227         int ret;
1228
1229         cpu_dev = get_cpu_device(cpu);
1230         if (!cpu_dev)
1231                 return -ENODEV;
1232
1233         np = of_node_get(cpu_dev->of_node);
1234         if (!np)
1235                 return -EINVAL;
1236
1237         ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1238         of_node_put(np);
1239         if (ret)
1240                 return -EINVAL;
1241
1242         Hz = *kHz * 1000;
1243         opp = dev_pm_opp_find_freq_ceil(cpu_dev, &Hz);
1244         if (IS_ERR(opp))
1245                 return -EINVAL;
1246
1247         mV = dev_pm_opp_get_voltage(opp) / 1000;
1248         dev_pm_opp_put(opp);
1249         if (!mV)
1250                 return -EINVAL;
1251
1252         tmp = (u64)cap * mV * mV * (Hz / 1000000);
1253         do_div(tmp, 1000000000);
1254
1255         *mW = (unsigned long)tmp;
1256         *kHz = Hz / 1000;
1257
1258         return 0;
1259 }
1260
1261 /**
1262  * dev_pm_opp_of_register_em() - Attempt to register an Energy Model
1263  * @cpus        : CPUs for which an Energy Model has to be registered
1264  *
1265  * This checks whether the "dynamic-power-coefficient" devicetree property has
1266  * been specified, and tries to register an Energy Model with it if it has.
1267  */
1268 void dev_pm_opp_of_register_em(struct cpumask *cpus)
1269 {
1270         struct em_data_callback em_cb = EM_DATA_CB(_get_cpu_power);
1271         int ret, nr_opp, cpu = cpumask_first(cpus);
1272         struct device *cpu_dev;
1273         struct device_node *np;
1274         u32 cap;
1275
1276         cpu_dev = get_cpu_device(cpu);
1277         if (!cpu_dev)
1278                 return;
1279
1280         nr_opp = dev_pm_opp_get_opp_count(cpu_dev);
1281         if (nr_opp <= 0)
1282                 return;
1283
1284         np = of_node_get(cpu_dev->of_node);
1285         if (!np)
1286                 return;
1287
1288         /*
1289          * Register an EM only if the 'dynamic-power-coefficient' property is
1290          * set in devicetree. It is assumed the voltage values are known if that
1291          * property is set since it is useless otherwise. If voltages are not
1292          * known, just let the EM registration fail with an error to alert the
1293          * user about the inconsistent configuration.
1294          */
1295         ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1296         of_node_put(np);
1297         if (ret || !cap)
1298                 return;
1299
1300         em_register_perf_domain(cpus, nr_opp, &em_cb);
1301 }
1302 EXPORT_SYMBOL_GPL(dev_pm_opp_of_register_em);