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 int _bandwidth_supported(struct device *dev, struct opp_table *opp_table)
 328 {
 329         struct device_node *np, *opp_np;
 330         struct property *prop;
 331
 332         if (!opp_table) {
 333                 np = of_node_get(dev->of_node);
 334                 if (!np)
 335                         return -ENODEV;
 336
 337                 opp_np = _opp_of_get_opp_desc_node(np, 0);
 338                 of_node_put(np);
 339         } else {
 340                 opp_np = of_node_get(opp_table->np);
 341         }
 342
 343         /* Lets not fail in case we are parsing opp-v1 bindings */
 344         if (!opp_np)
 345                 return 0;
 346
 347         /* Checking only first OPP is sufficient */
 348         np = of_get_next_available_child(opp_np, NULL);
 349         of_node_put(opp_np);
 350         if (!np) {
 351                 dev_err(dev, "OPP table empty\n");
 352                 return -EINVAL;
 353         }
 354
 355         prop = of_find_property(np, "opp-peak-kBps", NULL);
 356         of_node_put(np);
 357
 358         if (!prop || !prop->length)
 359                 return 0;
 360
 361         return 1;
 362 }
 363
 364 int dev_pm_opp_of_find_icc_paths(struct device *dev,
 365                                  struct opp_table *opp_table)
 366 {
 367         struct device_node *np;
 368         int ret, i, count, num_paths;
 369         struct icc_path **paths;
 370
 371         ret = _bandwidth_supported(dev, opp_table);
 372         if (ret <= 0)
 373                 return ret;
 374
 375         ret = 0;
 376
 377         np = of_node_get(dev->of_node);
 378         if (!np)
 379                 return 0;
 380
 381         count = of_count_phandle_with_args(np, "interconnects",
 382                                            "#interconnect-cells");
 383         of_node_put(np);
 384         if (count < 0)
 385                 return 0;
 386
 387         /* two phandles when #interconnect-cells = <1> */
 388         if (count % 2) {
 389                 dev_err(dev, "%s: Invalid interconnects values\n", __func__);
 390                 return -EINVAL;
 391         }
 392
 393         num_paths = count / 2;
 394         paths = kcalloc(num_paths, sizeof(*paths), GFP_KERNEL);
 395         if (!paths)
 396                 return -ENOMEM;
 397
 398         for (i = 0; i < num_paths; i++) {
 399                 paths[i] = of_icc_get_by_index(dev, i);
 400                 if (IS_ERR(paths[i])) {
 401                         ret = PTR_ERR(paths[i]);
 402                         if (ret != -EPROBE_DEFER) {
 403                                 dev_err(dev, "%s: Unable to get path%d: %d\n",
 404                                         __func__, i, ret);
 405                         }
 406                         goto err;
 407                 }
 408         }
 409
 410         if (opp_table) {
 411                 opp_table->paths = paths;
 412                 opp_table->path_count = num_paths;
 413                 return 0;
 414         }
 415
 416 err:
 417         while (i--)
 418                 icc_put(paths[i]);
 419
 420         kfree(paths);
 421
 422         return ret;
 423 }
 424 EXPORT_SYMBOL_GPL(dev_pm_opp_of_find_icc_paths);
 425
 426 static bool _opp_is_supported(struct device *dev, struct opp_table *opp_table,
 427                               struct device_node *np)
 428 {
 429         unsigned int levels = opp_table->supported_hw_count;
 430         int count, versions, ret, i, j;
 431         u32 val;
 432
 433         if (!opp_table->supported_hw) {
 434                 /*
 435                  * In the case that no supported_hw has been set by the
 436                  * platform but there is an opp-supported-hw value set for
 437                  * an OPP then the OPP should not be enabled as there is
 438                  * no way to see if the hardware supports it.
 439                  */
 440                 if (of_find_property(np, "opp-supported-hw", NULL))
 441                         return false;
 442                 else
 443                         return true;
 444         }
 445
 446         count = of_property_count_u32_elems(np, "opp-supported-hw");
 447         if (count <= 0 || count % levels) {
 448                 dev_err(dev, "%s: Invalid opp-supported-hw property (%d)\n",
 449                         __func__, count);
 450                 return false;
 451         }
 452
 453         versions = count / levels;
 454
 455         /* All levels in at least one of the versions should match */
 456         for (i = 0; i < versions; i++) {
 457                 bool supported = true;
 458
 459                 for (j = 0; j < levels; j++) {
 460                         ret = of_property_read_u32_index(np, "opp-supported-hw",
 461                                                          i * levels + j, &val);
 462                         if (ret) {
 463                                 dev_warn(dev, "%s: failed to read opp-supported-hw property at index %d: %d\n",
 464                                          __func__, i * levels + j, ret);
 465                                 return false;
 466                         }
 467
 468                         /* Check if the level is supported */
 469                         if (!(val & opp_table->supported_hw[j])) {
 470                                 supported = false;
 471                                 break;
 472                         }
 473                 }
 474
 475                 if (supported)
 476                         return true;
 477         }
 478
 479         return false;
 480 }
 481
 482 static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,
 483                               struct opp_table *opp_table)
 484 {
 485         u32 *microvolt, *microamp = NULL;
 486         int supplies = opp_table->regulator_count, vcount, icount, ret, i, j;
 487         struct property *prop = NULL;
 488         char name[NAME_MAX];
 489
 490         /* Search for "opp-microvolt-<name>" */
 491         if (opp_table->prop_name) {
 492                 snprintf(name, sizeof(name), "opp-microvolt-%s",
 493                          opp_table->prop_name);
 494                 prop = of_find_property(opp->np, name, NULL);
 495         }
 496
 497         if (!prop) {
 498                 /* Search for "opp-microvolt" */
 499                 sprintf(name, "opp-microvolt");
 500                 prop = of_find_property(opp->np, name, NULL);
 501
 502                 /* Missing property isn't a problem, but an invalid entry is */
 503                 if (!prop) {
 504                         if (unlikely(supplies == -1)) {
 505                                 /* Initialize regulator_count */
 506                                 opp_table->regulator_count = 0;
 507                                 return 0;
 508                         }
 509
 510                         if (!supplies)
 511                                 return 0;
 512
 513                         dev_err(dev, "%s: opp-microvolt missing although OPP managing regulators\n",
 514                                 __func__);
 515                         return -EINVAL;
 516                 }
 517         }
 518
 519         if (unlikely(supplies == -1)) {
 520                 /* Initialize regulator_count */
 521                 supplies = opp_table->regulator_count = 1;
 522         } else if (unlikely(!supplies)) {
 523                 dev_err(dev, "%s: opp-microvolt wasn't expected\n", __func__);
 524                 return -EINVAL;
 525         }
 526
 527         vcount = of_property_count_u32_elems(opp->np, name);
 528         if (vcount < 0) {
 529                 dev_err(dev, "%s: Invalid %s property (%d)\n",
 530                         __func__, name, vcount);
 531                 return vcount;
 532         }
 533
 534         /* There can be one or three elements per supply */
 535         if (vcount != supplies && vcount != supplies * 3) {
 536                 dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
 537                         __func__, name, vcount, supplies);
 538                 return -EINVAL;
 539         }
 540
 541         microvolt = kmalloc_array(vcount, sizeof(*microvolt), GFP_KERNEL);
 542         if (!microvolt)
 543                 return -ENOMEM;
 544
 545         ret = of_property_read_u32_array(opp->np, name, microvolt, vcount);
 546         if (ret) {
 547                 dev_err(dev, "%s: error parsing %s: %d\n", __func__, name, ret);
 548                 ret = -EINVAL;
 549                 goto free_microvolt;
 550         }
 551
 552         /* Search for "opp-microamp-<name>" */
 553         prop = NULL;
 554         if (opp_table->prop_name) {
 555                 snprintf(name, sizeof(name), "opp-microamp-%s",
 556                          opp_table->prop_name);
 557                 prop = of_find_property(opp->np, name, NULL);
 558         }
 559
 560         if (!prop) {
 561                 /* Search for "opp-microamp" */
 562                 sprintf(name, "opp-microamp");
 563                 prop = of_find_property(opp->np, name, NULL);
 564         }
 565
 566         if (prop) {
 567                 icount = of_property_count_u32_elems(opp->np, name);
 568                 if (icount < 0) {
 569                         dev_err(dev, "%s: Invalid %s property (%d)\n", __func__,
 570                                 name, icount);
 571                         ret = icount;
 572                         goto free_microvolt;
 573                 }
 574
 575                 if (icount != supplies) {
 576                         dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
 577                                 __func__, name, icount, supplies);
 578                         ret = -EINVAL;
 579                         goto free_microvolt;
 580                 }
 581
 582                 microamp = kmalloc_array(icount, sizeof(*microamp), GFP_KERNEL);
 583                 if (!microamp) {
 584                         ret = -EINVAL;
 585                         goto free_microvolt;
 586                 }
 587
 588                 ret = of_property_read_u32_array(opp->np, name, microamp,
 589                                                  icount);
 590                 if (ret) {
 591                         dev_err(dev, "%s: error parsing %s: %d\n", __func__,
 592                                 name, ret);
 593                         ret = -EINVAL;
 594                         goto free_microamp;
 595                 }
 596         }
 597
 598         for (i = 0, j = 0; i < supplies; i++) {
 599                 opp->supplies[i].u_volt = microvolt[j++];
 600
 601                 if (vcount == supplies) {
 602                         opp->supplies[i].u_volt_min = opp->supplies[i].u_volt;
 603                         opp->supplies[i].u_volt_max = opp->supplies[i].u_volt;
 604                 } else {
 605                         opp->supplies[i].u_volt_min = microvolt[j++];
 606                         opp->supplies[i].u_volt_max = microvolt[j++];
 607                 }
 608
 609                 if (microamp)
 610                         opp->supplies[i].u_amp = microamp[i];
 611         }
 612
 613 free_microamp:
 614         kfree(microamp);
 615 free_microvolt:
 616         kfree(microvolt);
 617
 618         return ret;
 619 }
 620
 621 /**
 622  * dev_pm_opp_of_remove_table() - Free OPP table entries created from static DT
 623  *                                entries
 624  * @dev:        device pointer used to lookup OPP table.
 625  *
 626  * Free OPPs created using static entries present in DT.
 627  */
 628 void dev_pm_opp_of_remove_table(struct device *dev)
 629 {
 630         dev_pm_opp_remove_table(dev);
 631 }
 632 EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table);
 633
 634 static int _read_bw(struct dev_pm_opp *new_opp, struct opp_table *table,
 635                     struct device_node *np, bool peak)
 636 {
 637         const char *name = peak ? "opp-peak-kBps" : "opp-avg-kBps";
 638         struct property *prop;
 639         int i, count, ret;
 640         u32 *bw;
 641
 642         prop = of_find_property(np, name, NULL);
 643         if (!prop)
 644                 return -ENODEV;
 645
 646         count = prop->length / sizeof(u32);
 647         if (table->path_count != count) {
 648                 pr_err("%s: Mismatch between %s and paths (%d %d)\n",
 649                                 __func__, name, count, table->path_count);
 650                 return -EINVAL;
 651         }
 652
 653         bw = kmalloc_array(count, sizeof(*bw), GFP_KERNEL);
 654         if (!bw)
 655                 return -ENOMEM;
 656
 657         ret = of_property_read_u32_array(np, name, bw, count);
 658         if (ret) {
 659                 pr_err("%s: Error parsing %s: %d\n", __func__, name, ret);
 660                 goto out;
 661         }
 662
 663         for (i = 0; i < count; i++) {
 664                 if (peak)
 665                         new_opp->bandwidth[i].peak = kBps_to_icc(bw[i]);
 666                 else
 667                         new_opp->bandwidth[i].avg = kBps_to_icc(bw[i]);
 668         }
 669
 670 out:
 671         kfree(bw);
 672         return ret;
 673 }
 674
 675 static int _read_opp_key(struct dev_pm_opp *new_opp, struct opp_table *table,
 676                          struct device_node *np, bool *rate_not_available)
 677 {
 678         bool found = false;
 679         u64 rate;
 680         int ret;
 681
 682         ret = of_property_read_u64(np, "opp-hz", &rate);
 683         if (!ret) {
 684                 /*
 685                  * Rate is defined as an unsigned long in clk API, and so
 686                  * casting explicitly to its type. Must be fixed once rate is 64
 687                  * bit guaranteed in clk API.
 688                  */
 689                 new_opp->rate = (unsigned long)rate;
 690                 found = true;
 691         }
 692         *rate_not_available = !!ret;
 693
 694         /*
 695          * Bandwidth consists of peak and average (optional) values:
 696          * opp-peak-kBps = <path1_value path2_value>;
 697          * opp-avg-kBps = <path1_value path2_value>;
 698          */
 699         ret = _read_bw(new_opp, table, np, true);
 700         if (!ret) {
 701                 found = true;
 702                 ret = _read_bw(new_opp, table, np, false);
 703         }
 704
 705         /* The properties were found but we failed to parse them */
 706         if (ret && ret != -ENODEV)
 707                 return ret;
 708
 709         if (!of_property_read_u32(np, "opp-level", &new_opp->level))
 710                 found = true;
 711
 712         if (found)
 713                 return 0;
 714
 715         return ret;
 716 }
 717
 718 /**
 719  * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings)
 720  * @opp_table:  OPP table
 721  * @dev:        device for which we do this operation
 722  * @np:         device node
 723  *
 724  * This function adds an opp definition to the opp table and returns status. The
 725  * opp can be controlled using dev_pm_opp_enable/disable functions and may be
 726  * removed by dev_pm_opp_remove.
 727  *
 728  * Return:
 729  * Valid OPP pointer:
 730  *              On success
 731  * NULL:
 732  *              Duplicate OPPs (both freq and volt are same) and opp->available
 733  *              OR if the OPP is not supported by hardware.
 734  * ERR_PTR(-EEXIST):
 735  *              Freq are same and volt are different OR
 736  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 737  * ERR_PTR(-ENOMEM):
 738  *              Memory allocation failure
 739  * ERR_PTR(-EINVAL):
 740  *              Failed parsing the OPP node
 741  */
 742 static struct dev_pm_opp *_opp_add_static_v2(struct opp_table *opp_table,
 743                 struct device *dev, struct device_node *np)
 744 {
 745         struct dev_pm_opp *new_opp;
 746         u32 val;
 747         int ret;
 748         bool rate_not_available = false;
 749
 750         new_opp = _opp_allocate(opp_table);
 751         if (!new_opp)
 752                 return ERR_PTR(-ENOMEM);
 753
 754         ret = _read_opp_key(new_opp, opp_table, np, &rate_not_available);
 755         if (ret < 0 && !opp_table->is_genpd) {
 756                 dev_err(dev, "%s: opp key field not found\n", __func__);
 757                 goto free_opp;
 758         }
 759
 760         /* Check if the OPP supports hardware's hierarchy of versions or not */
 761         if (!_opp_is_supported(dev, opp_table, np)) {
 762                 dev_dbg(dev, "OPP not supported by hardware: %lu\n",
 763                         new_opp->rate);
 764                 goto free_opp;
 765         }
 766
 767         new_opp->turbo = of_property_read_bool(np, "turbo-mode");
 768
 769         new_opp->np = np;
 770         new_opp->dynamic = false;
 771         new_opp->available = true;
 772
 773         ret = _of_opp_alloc_required_opps(opp_table, new_opp);
 774         if (ret)
 775                 goto free_opp;
 776
 777         if (!of_property_read_u32(np, "clock-latency-ns", &val))
 778                 new_opp->clock_latency_ns = val;
 779
 780         ret = opp_parse_supplies(new_opp, dev, opp_table);
 781         if (ret)
 782                 goto free_required_opps;
 783
 784         if (opp_table->is_genpd)
 785                 new_opp->pstate = pm_genpd_opp_to_performance_state(dev, new_opp);
 786
 787         ret = _opp_add(dev, new_opp, opp_table, rate_not_available);
 788         if (ret) {
 789                 /* Don't return error for duplicate OPPs */
 790                 if (ret == -EBUSY)
 791                         ret = 0;
 792                 goto free_required_opps;
 793         }
 794
 795         /* OPP to select on device suspend */
 796         if (of_property_read_bool(np, "opp-suspend")) {
 797                 if (opp_table->suspend_opp) {
 798                         /* Pick the OPP with higher rate as suspend OPP */
 799                         if (new_opp->rate > opp_table->suspend_opp->rate) {
 800                                 opp_table->suspend_opp->suspend = false;
 801                                 new_opp->suspend = true;
 802                                 opp_table->suspend_opp = new_opp;
 803                         }
 804                 } else {
 805                         new_opp->suspend = true;
 806                         opp_table->suspend_opp = new_opp;
 807                 }
 808         }
 809
 810         if (new_opp->clock_latency_ns > opp_table->clock_latency_ns_max)
 811                 opp_table->clock_latency_ns_max = new_opp->clock_latency_ns;
 812
 813         pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu\n",
 814                  __func__, new_opp->turbo, new_opp->rate,
 815                  new_opp->supplies[0].u_volt, new_opp->supplies[0].u_volt_min,
 816                  new_opp->supplies[0].u_volt_max, new_opp->clock_latency_ns);
 817
 818         /*
 819          * Notify the changes in the availability of the operable
 820          * frequency/voltage list.
 821          */
 822         blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ADD, new_opp);
 823         return new_opp;
 824
 825 free_required_opps:
 826         _of_opp_free_required_opps(opp_table, new_opp);
 827 free_opp:
 828         _opp_free(new_opp);
 829
 830         return ret ? ERR_PTR(ret) : NULL;
 831 }
 832
 833 /* Initializes OPP tables based on new bindings */
 834 static int _of_add_opp_table_v2(struct device *dev, struct opp_table *opp_table)
 835 {
 836         struct device_node *np;
 837         int ret, count = 0;
 838         struct dev_pm_opp *opp;
 839
 840         /* OPP table is already initialized for the device */
 841         mutex_lock(&opp_table->lock);
 842         if (opp_table->parsed_static_opps) {
 843                 opp_table->parsed_static_opps++;
 844                 mutex_unlock(&opp_table->lock);
 845                 return 0;
 846         }
 847
 848         opp_table->parsed_static_opps = 1;
 849         mutex_unlock(&opp_table->lock);
 850
 851         /* We have opp-table node now, iterate over it and add OPPs */
 852         for_each_available_child_of_node(opp_table->np, np) {
 853                 opp = _opp_add_static_v2(opp_table, dev, np);
 854                 if (IS_ERR(opp)) {
 855                         ret = PTR_ERR(opp);
 856                         dev_err(dev, "%s: Failed to add OPP, %d\n", __func__,
 857                                 ret);
 858                         of_node_put(np);
 859                         goto remove_static_opp;
 860                 } else if (opp) {
 861                         count++;
 862                 }
 863         }
 864
 865         /* There should be one or more OPPs defined */
 866         if (!count) {
 867                 dev_err(dev, "%s: no supported OPPs", __func__);
 868                 ret = -ENOENT;
 869                 goto remove_static_opp;
 870         }
 871
 872         list_for_each_entry(opp, &opp_table->opp_list, node) {
 873                 /* Any non-zero performance state would enable the feature */
 874                 if (opp->pstate) {
 875                         opp_table->genpd_performance_state = true;
 876                         break;
 877                 }
 878         }
 879
 880         return 0;
 881
 882 remove_static_opp:
 883         _opp_remove_all_static(opp_table);
 884
 885         return ret;
 886 }
 887
 888 /* Initializes OPP tables based on old-deprecated bindings */
 889 static int _of_add_opp_table_v1(struct device *dev, struct opp_table *opp_table)
 890 {
 891         const struct property *prop;
 892         const __be32 *val;
 893         int nr, ret = 0;
 894
 895         mutex_lock(&opp_table->lock);
 896         if (opp_table->parsed_static_opps) {
 897                 opp_table->parsed_static_opps++;
 898                 mutex_unlock(&opp_table->lock);
 899                 return 0;
 900         }
 901
 902         opp_table->parsed_static_opps = 1;
 903         mutex_unlock(&opp_table->lock);
 904
 905         prop = of_find_property(dev->of_node, "operating-points", NULL);
 906         if (!prop) {
 907                 ret = -ENODEV;
 908                 goto remove_static_opp;
 909         }
 910         if (!prop->value) {
 911                 ret = -ENODATA;
 912                 goto remove_static_opp;
 913         }
 914
 915         /*
 916          * Each OPP is a set of tuples consisting of frequency and
 917          * voltage like <freq-kHz vol-uV>.
 918          */
 919         nr = prop->length / sizeof(u32);
 920         if (nr % 2) {
 921                 dev_err(dev, "%s: Invalid OPP table\n", __func__);
 922                 ret = -EINVAL;
 923                 goto remove_static_opp;
 924         }
 925
 926         val = prop->value;
 927         while (nr) {
 928                 unsigned long freq = be32_to_cpup(val++) * 1000;
 929                 unsigned long volt = be32_to_cpup(val++);
 930
 931                 ret = _opp_add_v1(opp_table, dev, freq, volt, false);
 932                 if (ret) {
 933                         dev_err(dev, "%s: Failed to add OPP %ld (%d)\n",
 934                                 __func__, freq, ret);
 935                         goto remove_static_opp;
 936                 }
 937                 nr -= 2;
 938         }
 939
 940         return 0;
 941
 942 remove_static_opp:
 943         _opp_remove_all_static(opp_table);
 944
 945         return ret;
 946 }
 947
 948 /**
 949  * dev_pm_opp_of_add_table() - Initialize opp table from device tree
 950  * @dev:        device pointer used to lookup OPP table.
 951  *
 952  * Register the initial OPP table with the OPP library for given device.
 953  *
 954  * Return:
 955  * 0            On success OR
 956  *              Duplicate OPPs (both freq and volt are same) and opp->available
 957  * -EEXIST      Freq are same and volt are different OR
 958  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 959  * -ENOMEM      Memory allocation failure
 960  * -ENODEV      when 'operating-points' property is not found or is invalid data
 961  *              in device node.
 962  * -ENODATA     when empty 'operating-points' property is found
 963  * -EINVAL      when invalid entries are found in opp-v2 table
 964  */
 965 int dev_pm_opp_of_add_table(struct device *dev)
 966 {
 967         struct opp_table *opp_table;
 968         int ret;
 969
 970         opp_table = dev_pm_opp_get_opp_table_indexed(dev, 0);
 971         if (IS_ERR(opp_table))
 972                 return PTR_ERR(opp_table);
 973
 974         /*
 975          * OPPs have two version of bindings now. Also try the old (v1)
 976          * bindings for backward compatibility with older dtbs.
 977          */
 978         if (opp_table->np)
 979                 ret = _of_add_opp_table_v2(dev, opp_table);
 980         else
 981                 ret = _of_add_opp_table_v1(dev, opp_table);
 982
 983         if (ret)
 984                 dev_pm_opp_put_opp_table(opp_table);
 985
 986         return ret;
 987 }
 988 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table);
 989
 990 /**
 991  * dev_pm_opp_of_add_table_indexed() - Initialize indexed opp table from device tree
 992  * @dev:        device pointer used to lookup OPP table.
 993  * @index:      Index number.
 994  *
 995  * Register the initial OPP table with the OPP library for given device only
 996  * using the "operating-points-v2" property.
 997  *
 998  * Return:
 999  * 0            On success OR
1000  *              Duplicate OPPs (both freq and volt are same) and opp->available
1001  * -EEXIST      Freq are same and volt are different OR
1002  *              Duplicate OPPs (both freq and volt are same) and !opp->available
1003  * -ENOMEM      Memory allocation failure
1004  * -ENODEV      when 'operating-points' property is not found or is invalid data
1005  *              in device node.
1006  * -ENODATA     when empty 'operating-points' property is found
1007  * -EINVAL      when invalid entries are found in opp-v2 table
1008  */
1009 int dev_pm_opp_of_add_table_indexed(struct device *dev, int index)
1010 {
1011         struct opp_table *opp_table;
1012         int ret, count;
1013
1014         if (index) {
1015                 /*
1016                  * If only one phandle is present, then the same OPP table
1017                  * applies for all index requests.
1018                  */
1019                 count = of_count_phandle_with_args(dev->of_node,
1020                                                    "operating-points-v2", NULL);
1021                 if (count == 1)
1022                         index = 0;
1023         }
1024
1025         opp_table = dev_pm_opp_get_opp_table_indexed(dev, index);
1026         if (IS_ERR(opp_table))
1027                 return PTR_ERR(opp_table);
1028
1029         ret = _of_add_opp_table_v2(dev, opp_table);
1030         if (ret)
1031                 dev_pm_opp_put_opp_table(opp_table);
1032
1033         return ret;
1034 }
1035 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table_indexed);
1036
1037 /* CPU device specific helpers */
1038
1039 /**
1040  * dev_pm_opp_of_cpumask_remove_table() - Removes OPP table for @cpumask
1041  * @cpumask:    cpumask for which OPP table needs to be removed
1042  *
1043  * This removes the OPP tables for CPUs present in the @cpumask.
1044  * This should be used only to remove static entries created from DT.
1045  */
1046 void dev_pm_opp_of_cpumask_remove_table(const struct cpumask *cpumask)
1047 {
1048         _dev_pm_opp_cpumask_remove_table(cpumask, -1);
1049 }
1050 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_remove_table);
1051
1052 /**
1053  * dev_pm_opp_of_cpumask_add_table() - Adds OPP table for @cpumask
1054  * @cpumask:    cpumask for which OPP table needs to be added.
1055  *
1056  * This adds the OPP tables for CPUs present in the @cpumask.
1057  */
1058 int dev_pm_opp_of_cpumask_add_table(const struct cpumask *cpumask)
1059 {
1060         struct device *cpu_dev;
1061         int cpu, ret;
1062
1063         if (WARN_ON(cpumask_empty(cpumask)))
1064                 return -ENODEV;
1065
1066         for_each_cpu(cpu, cpumask) {
1067                 cpu_dev = get_cpu_device(cpu);
1068                 if (!cpu_dev) {
1069                         pr_err("%s: failed to get cpu%d device\n", __func__,
1070                                cpu);
1071                         ret = -ENODEV;
1072                         goto remove_table;
1073                 }
1074
1075                 ret = dev_pm_opp_of_add_table(cpu_dev);
1076                 if (ret) {
1077                         /*
1078                          * OPP may get registered dynamically, don't print error
1079                          * message here.
1080                          */
1081                         pr_debug("%s: couldn't find opp table for cpu:%d, %d\n",
1082                                  __func__, cpu, ret);
1083
1084                         goto remove_table;
1085                 }
1086         }
1087
1088         return 0;
1089
1090 remove_table:
1091         /* Free all other OPPs */
1092         _dev_pm_opp_cpumask_remove_table(cpumask, cpu);
1093
1094         return ret;
1095 }
1096 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_add_table);
1097
1098 /*
1099  * Works only for OPP v2 bindings.
1100  *
1101  * Returns -ENOENT if operating-points-v2 bindings aren't supported.
1102  */
1103 /**
1104  * dev_pm_opp_of_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with
1105  *                                    @cpu_dev using operating-points-v2
1106  *                                    bindings.
1107  *
1108  * @cpu_dev:    CPU device for which we do this operation
1109  * @cpumask:    cpumask to update with information of sharing CPUs
1110  *
1111  * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev.
1112  *
1113  * Returns -ENOENT if operating-points-v2 isn't present for @cpu_dev.
1114  */
1115 int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev,
1116                                    struct cpumask *cpumask)
1117 {
1118         struct device_node *np, *tmp_np, *cpu_np;
1119         int cpu, ret = 0;
1120
1121         /* Get OPP descriptor node */
1122         np = dev_pm_opp_of_get_opp_desc_node(cpu_dev);
1123         if (!np) {
1124                 dev_dbg(cpu_dev, "%s: Couldn't find opp node.\n", __func__);
1125                 return -ENOENT;
1126         }
1127
1128         cpumask_set_cpu(cpu_dev->id, cpumask);
1129
1130         /* OPPs are shared ? */
1131         if (!of_property_read_bool(np, "opp-shared"))
1132                 goto put_cpu_node;
1133
1134         for_each_possible_cpu(cpu) {
1135                 if (cpu == cpu_dev->id)
1136                         continue;
1137
1138                 cpu_np = of_cpu_device_node_get(cpu);
1139                 if (!cpu_np) {
1140                         dev_err(cpu_dev, "%s: failed to get cpu%d node\n",
1141                                 __func__, cpu);
1142                         ret = -ENOENT;
1143                         goto put_cpu_node;
1144                 }
1145
1146                 /* Get OPP descriptor node */
1147                 tmp_np = _opp_of_get_opp_desc_node(cpu_np, 0);
1148                 of_node_put(cpu_np);
1149                 if (!tmp_np) {
1150                         pr_err("%pOF: Couldn't find opp node\n", cpu_np);
1151                         ret = -ENOENT;
1152                         goto put_cpu_node;
1153                 }
1154
1155                 /* CPUs are sharing opp node */
1156                 if (np == tmp_np)
1157                         cpumask_set_cpu(cpu, cpumask);
1158
1159                 of_node_put(tmp_np);
1160         }
1161
1162 put_cpu_node:
1163         of_node_put(np);
1164         return ret;
1165 }
1166 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus);
1167
1168 /**
1169  * of_get_required_opp_performance_state() - Search for required OPP and return its performance state.
1170  * @np: Node that contains the "required-opps" property.
1171  * @index: Index of the phandle to parse.
1172  *
1173  * Returns the performance state of the OPP pointed out by the "required-opps"
1174  * property at @index in @np.
1175  *
1176  * Return: Zero or positive performance state on success, otherwise negative
1177  * value on errors.
1178  */
1179 int of_get_required_opp_performance_state(struct device_node *np, int index)
1180 {
1181         struct dev_pm_opp *opp;
1182         struct device_node *required_np;
1183         struct opp_table *opp_table;
1184         int pstate = -EINVAL;
1185
1186         required_np = of_parse_required_opp(np, index);
1187         if (!required_np)
1188                 return -ENODEV;
1189
1190         opp_table = _find_table_of_opp_np(required_np);
1191         if (IS_ERR(opp_table)) {
1192                 pr_err("%s: Failed to find required OPP table %pOF: %ld\n",
1193                        __func__, np, PTR_ERR(opp_table));
1194                 goto put_required_np;
1195         }
1196
1197         opp = _find_opp_of_np(opp_table, required_np);
1198         if (opp) {
1199                 pstate = opp->pstate;
1200                 dev_pm_opp_put(opp);
1201         }
1202
1203         dev_pm_opp_put_opp_table(opp_table);
1204
1205 put_required_np:
1206         of_node_put(required_np);
1207
1208         return pstate;
1209 }
1210 EXPORT_SYMBOL_GPL(of_get_required_opp_performance_state);
1211
1212 /**
1213  * dev_pm_opp_get_of_node() - Gets the DT node corresponding to an opp
1214  * @opp:        opp for which DT node has to be returned for
1215  *
1216  * Return: DT node corresponding to the opp, else 0 on success.
1217  *
1218  * The caller needs to put the node with of_node_put() after using it.
1219  */
1220 struct device_node *dev_pm_opp_get_of_node(struct dev_pm_opp *opp)
1221 {
1222         if (IS_ERR_OR_NULL(opp)) {
1223                 pr_err("%s: Invalid parameters\n", __func__);
1224                 return NULL;
1225         }
1226
1227         return of_node_get(opp->np);
1228 }
1229 EXPORT_SYMBOL_GPL(dev_pm_opp_get_of_node);
1230
1231 /*
1232  * Callback function provided to the Energy Model framework upon registration.
1233  * This computes the power estimated by @dev at @kHz if it is the frequency
1234  * of an existing OPP, or at the frequency of the first OPP above @kHz otherwise
1235  * (see dev_pm_opp_find_freq_ceil()). This function updates @kHz to the ceiled
1236  * frequency and @mW to the associated power. The power is estimated as
1237  * P = C * V^2 * f with C being the device's capacitance and V and f
1238  * respectively the voltage and frequency of the OPP.
1239  *
1240  * Returns -EINVAL if the power calculation failed because of missing
1241  * parameters, 0 otherwise.
1242  */
1243 static int __maybe_unused _get_power(unsigned long *mW, unsigned long *kHz,
1244                                      struct device *dev)
1245 {
1246         struct dev_pm_opp *opp;
1247         struct device_node *np;
1248         unsigned long mV, Hz;
1249         u32 cap;
1250         u64 tmp;
1251         int ret;
1252
1253         np = of_node_get(dev->of_node);
1254         if (!np)
1255                 return -EINVAL;
1256
1257         ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1258         of_node_put(np);
1259         if (ret)
1260                 return -EINVAL;
1261
1262         Hz = *kHz * 1000;
1263         opp = dev_pm_opp_find_freq_ceil(dev, &Hz);
1264         if (IS_ERR(opp))
1265                 return -EINVAL;
1266
1267         mV = dev_pm_opp_get_voltage(opp) / 1000;
1268         dev_pm_opp_put(opp);
1269         if (!mV)
1270                 return -EINVAL;
1271
1272         tmp = (u64)cap * mV * mV * (Hz / 1000000);
1273         do_div(tmp, 1000000000);
1274
1275         *mW = (unsigned long)tmp;
1276         *kHz = Hz / 1000;
1277
1278         return 0;
1279 }
1280
1281 /**
1282  * dev_pm_opp_of_register_em() - Attempt to register an Energy Model
1283  * @dev         : Device for which an Energy Model has to be registered
1284  * @cpus        : CPUs for which an Energy Model has to be registered. For
1285  *              other type of devices it should be set to NULL.
1286  *
1287  * This checks whether the "dynamic-power-coefficient" devicetree property has
1288  * been specified, and tries to register an Energy Model with it if it has.
1289  * Having this property means the voltages are known for OPPs and the EM
1290  * might be calculated.
1291  */
1292 int dev_pm_opp_of_register_em(struct device *dev, struct cpumask *cpus)
1293 {
1294         struct em_data_callback em_cb = EM_DATA_CB(_get_power);
1295         struct device_node *np;
1296         int ret, nr_opp;
1297         u32 cap;
1298
1299         if (IS_ERR_OR_NULL(dev)) {
1300                 ret = -EINVAL;
1301                 goto failed;
1302         }
1303
1304         nr_opp = dev_pm_opp_get_opp_count(dev);
1305         if (nr_opp <= 0) {
1306                 ret = -EINVAL;
1307                 goto failed;
1308         }
1309
1310         np = of_node_get(dev->of_node);
1311         if (!np) {
1312                 ret = -EINVAL;
1313                 goto failed;
1314         }
1315
1316         /*
1317          * Register an EM only if the 'dynamic-power-coefficient' property is
1318          * set in devicetree. It is assumed the voltage values are known if that
1319          * property is set since it is useless otherwise. If voltages are not
1320          * known, just let the EM registration fail with an error to alert the
1321          * user about the inconsistent configuration.
1322          */
1323         ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1324         of_node_put(np);
1325         if (ret || !cap) {
1326                 dev_dbg(dev, "Couldn't find proper 'dynamic-power-coefficient' in DT\n");
1327                 ret = -EINVAL;
1328                 goto failed;
1329         }
1330
1331         ret = em_dev_register_perf_domain(dev, nr_opp, &em_cb, cpus);
1332         if (ret)
1333                 goto failed;
1334
1335         return 0;
1336
1337 failed:
1338         dev_dbg(dev, "Couldn't register Energy Model %d\n", ret);
1339         return ret;
1340 }
1341 EXPORT_SYMBOL_GPL(dev_pm_opp_of_register_em);