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         opp_table_np = of_get_parent(opp_np);
 116         if (!opp_table_np)
 117                 goto err;
 118
 119         /* It is safe to put the node now as all we need now is its address */
 120         of_node_put(opp_table_np);
 121
 122         mutex_lock(&opp_table_lock);
 123         list_for_each_entry(opp_table, &opp_tables, node) {
 124                 if (opp_table_np == opp_table->np) {
 125                         _get_opp_table_kref(opp_table);
 126                         mutex_unlock(&opp_table_lock);
 127                         return opp_table;
 128                 }
 129         }
 130         mutex_unlock(&opp_table_lock);
 131
 132 err:
 133         return ERR_PTR(-ENODEV);
 134 }
 135
 136 /* Free resources previously acquired by _opp_table_alloc_required_tables() */
 137 static void _opp_table_free_required_tables(struct opp_table *opp_table)
 138 {
 139         struct opp_table **required_opp_tables = opp_table->required_opp_tables;
 140         int i;
 141
 142         if (!required_opp_tables)
 143                 return;
 144
 145         for (i = 0; i < opp_table->required_opp_count; i++) {
 146                 if (IS_ERR_OR_NULL(required_opp_tables[i]))
 147                         break;
 148
 149                 dev_pm_opp_put_opp_table(required_opp_tables[i]);
 150         }
 151
 152         kfree(required_opp_tables);
 153
 154         opp_table->required_opp_count = 0;
 155         opp_table->required_opp_tables = NULL;
 156 }
 157
 158 /*
 159  * Populate all devices and opp tables which are part of "required-opps" list.
 160  * Checking only the first OPP node should be enough.
 161  */
 162 static void _opp_table_alloc_required_tables(struct opp_table *opp_table,
 163                                              struct device *dev,
 164                                              struct device_node *opp_np)
 165 {
 166         struct opp_table **required_opp_tables;
 167         struct device_node *required_np, *np;
 168         int count, i;
 169
 170         /* Traversing the first OPP node is all we need */
 171         np = of_get_next_available_child(opp_np, NULL);
 172         if (!np) {
 173                 dev_warn(dev, "Empty OPP table\n");
 174
 175                 return;
 176         }
 177
 178         count = of_count_phandle_with_args(np, "required-opps", NULL);
 179         if (!count)
 180                 goto put_np;
 181
 182         required_opp_tables = kcalloc(count, sizeof(*required_opp_tables),
 183                                       GFP_KERNEL);
 184         if (!required_opp_tables)
 185                 goto put_np;
 186
 187         opp_table->required_opp_tables = required_opp_tables;
 188         opp_table->required_opp_count = count;
 189
 190         for (i = 0; i < count; i++) {
 191                 required_np = of_parse_required_opp(np, i);
 192                 if (!required_np)
 193                         goto free_required_tables;
 194
 195                 required_opp_tables[i] = _find_table_of_opp_np(required_np);
 196                 of_node_put(required_np);
 197
 198                 if (IS_ERR(required_opp_tables[i]))
 199                         goto free_required_tables;
 200
 201                 /*
 202                  * We only support genpd's OPPs in the "required-opps" for now,
 203                  * as we don't know how much about other cases. Error out if the
 204                  * required OPP doesn't belong to a genpd.
 205                  */
 206                 if (!required_opp_tables[i]->is_genpd) {
 207                         dev_err(dev, "required-opp doesn't belong to genpd: %pOF\n",
 208                                 required_np);
 209                         goto free_required_tables;
 210                 }
 211         }
 212
 213         goto put_np;
 214
 215 free_required_tables:
 216         _opp_table_free_required_tables(opp_table);
 217 put_np:
 218         of_node_put(np);
 219 }
 220
 221 void _of_init_opp_table(struct opp_table *opp_table, struct device *dev,
 222                         int index)
 223 {
 224         struct device_node *np, *opp_np;
 225         u32 val;
 226
 227         /*
 228          * Only required for backward compatibility with v1 bindings, but isn't
 229          * harmful for other cases. And so we do it unconditionally.
 230          */
 231         np = of_node_get(dev->of_node);
 232         if (!np)
 233                 return;
 234
 235         if (!of_property_read_u32(np, "clock-latency", &val))
 236                 opp_table->clock_latency_ns_max = val;
 237         of_property_read_u32(np, "voltage-tolerance",
 238                              &opp_table->voltage_tolerance_v1);
 239
 240         if (of_find_property(np, "#power-domain-cells", NULL))
 241                 opp_table->is_genpd = true;
 242
 243         /* Get OPP table node */
 244         opp_np = _opp_of_get_opp_desc_node(np, index);
 245         of_node_put(np);
 246
 247         if (!opp_np)
 248                 return;
 249
 250         if (of_property_read_bool(opp_np, "opp-shared"))
 251                 opp_table->shared_opp = OPP_TABLE_ACCESS_SHARED;
 252         else
 253                 opp_table->shared_opp = OPP_TABLE_ACCESS_EXCLUSIVE;
 254
 255         opp_table->np = opp_np;
 256
 257         _opp_table_alloc_required_tables(opp_table, dev, opp_np);
 258         of_node_put(opp_np);
 259 }
 260
 261 void _of_clear_opp_table(struct opp_table *opp_table)
 262 {
 263         _opp_table_free_required_tables(opp_table);
 264 }
 265
 266 /*
 267  * Release all resources previously acquired with a call to
 268  * _of_opp_alloc_required_opps().
 269  */
 270 void _of_opp_free_required_opps(struct opp_table *opp_table,
 271                                 struct dev_pm_opp *opp)
 272 {
 273         struct dev_pm_opp **required_opps = opp->required_opps;
 274         int i;
 275
 276         if (!required_opps)
 277                 return;
 278
 279         for (i = 0; i < opp_table->required_opp_count; i++) {
 280                 if (!required_opps[i])
 281                         break;
 282
 283                 /* Put the reference back */
 284                 dev_pm_opp_put(required_opps[i]);
 285         }
 286
 287         kfree(required_opps);
 288         opp->required_opps = NULL;
 289 }
 290
 291 /* Populate all required OPPs which are part of "required-opps" list */
 292 static int _of_opp_alloc_required_opps(struct opp_table *opp_table,
 293                                        struct dev_pm_opp *opp)
 294 {
 295         struct dev_pm_opp **required_opps;
 296         struct opp_table *required_table;
 297         struct device_node *np;
 298         int i, ret, count = opp_table->required_opp_count;
 299
 300         if (!count)
 301                 return 0;
 302
 303         required_opps = kcalloc(count, sizeof(*required_opps), GFP_KERNEL);
 304         if (!required_opps)
 305                 return -ENOMEM;
 306
 307         opp->required_opps = required_opps;
 308
 309         for (i = 0; i < count; i++) {
 310                 required_table = opp_table->required_opp_tables[i];
 311
 312                 np = of_parse_required_opp(opp->np, i);
 313                 if (unlikely(!np)) {
 314                         ret = -ENODEV;
 315                         goto free_required_opps;
 316                 }
 317
 318                 required_opps[i] = _find_opp_of_np(required_table, np);
 319                 of_node_put(np);
 320
 321                 if (!required_opps[i]) {
 322                         pr_err("%s: Unable to find required OPP node: %pOF (%d)\n",
 323                                __func__, opp->np, i);
 324                         ret = -ENODEV;
 325                         goto free_required_opps;
 326                 }
 327         }
 328
 329         return 0;
 330
 331 free_required_opps:
 332         _of_opp_free_required_opps(opp_table, opp);
 333
 334         return ret;
 335 }
 336
 337 static int _bandwidth_supported(struct device *dev, struct opp_table *opp_table)
 338 {
 339         struct device_node *np, *opp_np;
 340         struct property *prop;
 341
 342         if (!opp_table) {
 343                 np = of_node_get(dev->of_node);
 344                 if (!np)
 345                         return -ENODEV;
 346
 347                 opp_np = _opp_of_get_opp_desc_node(np, 0);
 348                 of_node_put(np);
 349         } else {
 350                 opp_np = of_node_get(opp_table->np);
 351         }
 352
 353         /* Lets not fail in case we are parsing opp-v1 bindings */
 354         if (!opp_np)
 355                 return 0;
 356
 357         /* Checking only first OPP is sufficient */
 358         np = of_get_next_available_child(opp_np, NULL);
 359         if (!np) {
 360                 dev_err(dev, "OPP table empty\n");
 361                 return -EINVAL;
 362         }
 363         of_node_put(opp_np);
 364
 365         prop = of_find_property(np, "opp-peak-kBps", NULL);
 366         of_node_put(np);
 367
 368         if (!prop || !prop->length)
 369                 return 0;
 370
 371         return 1;
 372 }
 373
 374 int dev_pm_opp_of_find_icc_paths(struct device *dev,
 375                                  struct opp_table *opp_table)
 376 {
 377         struct device_node *np;
 378         int ret, i, count, num_paths;
 379         struct icc_path **paths;
 380
 381         ret = _bandwidth_supported(dev, opp_table);
 382         if (ret == -EINVAL)
 383                 return 0; /* Empty OPP table is a valid corner-case, let's not fail */
 384         else if (ret <= 0)
 385                 return ret;
 386
 387         ret = 0;
 388
 389         np = of_node_get(dev->of_node);
 390         if (!np)
 391                 return 0;
 392
 393         count = of_count_phandle_with_args(np, "interconnects",
 394                                            "#interconnect-cells");
 395         of_node_put(np);
 396         if (count < 0)
 397                 return 0;
 398
 399         /* two phandles when #interconnect-cells = <1> */
 400         if (count % 2) {
 401                 dev_err(dev, "%s: Invalid interconnects values\n", __func__);
 402                 return -EINVAL;
 403         }
 404
 405         num_paths = count / 2;
 406         paths = kcalloc(num_paths, sizeof(*paths), GFP_KERNEL);
 407         if (!paths)
 408                 return -ENOMEM;
 409
 410         for (i = 0; i < num_paths; i++) {
 411                 paths[i] = of_icc_get_by_index(dev, i);
 412                 if (IS_ERR(paths[i])) {
 413                         ret = PTR_ERR(paths[i]);
 414                         if (ret != -EPROBE_DEFER) {
 415                                 dev_err(dev, "%s: Unable to get path%d: %d\n",
 416                                         __func__, i, ret);
 417                         }
 418                         goto err;
 419                 }
 420         }
 421
 422         if (opp_table) {
 423                 opp_table->paths = paths;
 424                 opp_table->path_count = num_paths;
 425                 return 0;
 426         }
 427
 428 err:
 429         while (i--)
 430                 icc_put(paths[i]);
 431
 432         kfree(paths);
 433
 434         return ret;
 435 }
 436 EXPORT_SYMBOL_GPL(dev_pm_opp_of_find_icc_paths);
 437
 438 static bool _opp_is_supported(struct device *dev, struct opp_table *opp_table,
 439                               struct device_node *np)
 440 {
 441         unsigned int levels = opp_table->supported_hw_count;
 442         int count, versions, ret, i, j;
 443         u32 val;
 444
 445         if (!opp_table->supported_hw) {
 446                 /*
 447                  * In the case that no supported_hw has been set by the
 448                  * platform but there is an opp-supported-hw value set for
 449                  * an OPP then the OPP should not be enabled as there is
 450                  * no way to see if the hardware supports it.
 451                  */
 452                 if (of_find_property(np, "opp-supported-hw", NULL))
 453                         return false;
 454                 else
 455                         return true;
 456         }
 457
 458         count = of_property_count_u32_elems(np, "opp-supported-hw");
 459         if (count <= 0 || count % levels) {
 460                 dev_err(dev, "%s: Invalid opp-supported-hw property (%d)\n",
 461                         __func__, count);
 462                 return false;
 463         }
 464
 465         versions = count / levels;
 466
 467         /* All levels in at least one of the versions should match */
 468         for (i = 0; i < versions; i++) {
 469                 bool supported = true;
 470
 471                 for (j = 0; j < levels; j++) {
 472                         ret = of_property_read_u32_index(np, "opp-supported-hw",
 473                                                          i * levels + j, &val);
 474                         if (ret) {
 475                                 dev_warn(dev, "%s: failed to read opp-supported-hw property at index %d: %d\n",
 476                                          __func__, i * levels + j, ret);
 477                                 return false;
 478                         }
 479
 480                         /* Check if the level is supported */
 481                         if (!(val & opp_table->supported_hw[j])) {
 482                                 supported = false;
 483                                 break;
 484                         }
 485                 }
 486
 487                 if (supported)
 488                         return true;
 489         }
 490
 491         return false;
 492 }
 493
 494 static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,
 495                               struct opp_table *opp_table)
 496 {
 497         u32 *microvolt, *microamp = NULL;
 498         int supplies = opp_table->regulator_count, vcount, icount, ret, i, j;
 499         struct property *prop = NULL;
 500         char name[NAME_MAX];
 501
 502         /* Search for "opp-microvolt-<name>" */
 503         if (opp_table->prop_name) {
 504                 snprintf(name, sizeof(name), "opp-microvolt-%s",
 505                          opp_table->prop_name);
 506                 prop = of_find_property(opp->np, name, NULL);
 507         }
 508
 509         if (!prop) {
 510                 /* Search for "opp-microvolt" */
 511                 sprintf(name, "opp-microvolt");
 512                 prop = of_find_property(opp->np, name, NULL);
 513
 514                 /* Missing property isn't a problem, but an invalid entry is */
 515                 if (!prop) {
 516                         if (unlikely(supplies == -1)) {
 517                                 /* Initialize regulator_count */
 518                                 opp_table->regulator_count = 0;
 519                                 return 0;
 520                         }
 521
 522                         if (!supplies)
 523                                 return 0;
 524
 525                         dev_err(dev, "%s: opp-microvolt missing although OPP managing regulators\n",
 526                                 __func__);
 527                         return -EINVAL;
 528                 }
 529         }
 530
 531         if (unlikely(supplies == -1)) {
 532                 /* Initialize regulator_count */
 533                 supplies = opp_table->regulator_count = 1;
 534         } else if (unlikely(!supplies)) {
 535                 dev_err(dev, "%s: opp-microvolt wasn't expected\n", __func__);
 536                 return -EINVAL;
 537         }
 538
 539         vcount = of_property_count_u32_elems(opp->np, name);
 540         if (vcount < 0) {
 541                 dev_err(dev, "%s: Invalid %s property (%d)\n",
 542                         __func__, name, vcount);
 543                 return vcount;
 544         }
 545
 546         /* There can be one or three elements per supply */
 547         if (vcount != supplies && vcount != supplies * 3) {
 548                 dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
 549                         __func__, name, vcount, supplies);
 550                 return -EINVAL;
 551         }
 552
 553         microvolt = kmalloc_array(vcount, sizeof(*microvolt), GFP_KERNEL);
 554         if (!microvolt)
 555                 return -ENOMEM;
 556
 557         ret = of_property_read_u32_array(opp->np, name, microvolt, vcount);
 558         if (ret) {
 559                 dev_err(dev, "%s: error parsing %s: %d\n", __func__, name, ret);
 560                 ret = -EINVAL;
 561                 goto free_microvolt;
 562         }
 563
 564         /* Search for "opp-microamp-<name>" */
 565         prop = NULL;
 566         if (opp_table->prop_name) {
 567                 snprintf(name, sizeof(name), "opp-microamp-%s",
 568                          opp_table->prop_name);
 569                 prop = of_find_property(opp->np, name, NULL);
 570         }
 571
 572         if (!prop) {
 573                 /* Search for "opp-microamp" */
 574                 sprintf(name, "opp-microamp");
 575                 prop = of_find_property(opp->np, name, NULL);
 576         }
 577
 578         if (prop) {
 579                 icount = of_property_count_u32_elems(opp->np, name);
 580                 if (icount < 0) {
 581                         dev_err(dev, "%s: Invalid %s property (%d)\n", __func__,
 582                                 name, icount);
 583                         ret = icount;
 584                         goto free_microvolt;
 585                 }
 586
 587                 if (icount != supplies) {
 588                         dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
 589                                 __func__, name, icount, supplies);
 590                         ret = -EINVAL;
 591                         goto free_microvolt;
 592                 }
 593
 594                 microamp = kmalloc_array(icount, sizeof(*microamp), GFP_KERNEL);
 595                 if (!microamp) {
 596                         ret = -EINVAL;
 597                         goto free_microvolt;
 598                 }
 599
 600                 ret = of_property_read_u32_array(opp->np, name, microamp,
 601                                                  icount);
 602                 if (ret) {
 603                         dev_err(dev, "%s: error parsing %s: %d\n", __func__,
 604                                 name, ret);
 605                         ret = -EINVAL;
 606                         goto free_microamp;
 607                 }
 608         }
 609
 610         for (i = 0, j = 0; i < supplies; i++) {
 611                 opp->supplies[i].u_volt = microvolt[j++];
 612
 613                 if (vcount == supplies) {
 614                         opp->supplies[i].u_volt_min = opp->supplies[i].u_volt;
 615                         opp->supplies[i].u_volt_max = opp->supplies[i].u_volt;
 616                 } else {
 617                         opp->supplies[i].u_volt_min = microvolt[j++];
 618                         opp->supplies[i].u_volt_max = microvolt[j++];
 619                 }
 620
 621                 if (microamp)
 622                         opp->supplies[i].u_amp = microamp[i];
 623         }
 624
 625 free_microamp:
 626         kfree(microamp);
 627 free_microvolt:
 628         kfree(microvolt);
 629
 630         return ret;
 631 }
 632
 633 /**
 634  * dev_pm_opp_of_remove_table() - Free OPP table entries created from static DT
 635  *                                entries
 636  * @dev:        device pointer used to lookup OPP table.
 637  *
 638  * Free OPPs created using static entries present in DT.
 639  */
 640 void dev_pm_opp_of_remove_table(struct device *dev)
 641 {
 642         dev_pm_opp_remove_table(dev);
 643 }
 644 EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table);
 645
 646 static int _read_bw(struct dev_pm_opp *new_opp, struct opp_table *table,
 647                     struct device_node *np, bool peak)
 648 {
 649         const char *name = peak ? "opp-peak-kBps" : "opp-avg-kBps";
 650         struct property *prop;
 651         int i, count, ret;
 652         u32 *bw;
 653
 654         prop = of_find_property(np, name, NULL);
 655         if (!prop)
 656                 return -ENODEV;
 657
 658         count = prop->length / sizeof(u32);
 659         if (table->path_count != count) {
 660                 pr_err("%s: Mismatch between %s and paths (%d %d)\n",
 661                                 __func__, name, count, table->path_count);
 662                 return -EINVAL;
 663         }
 664
 665         bw = kmalloc_array(count, sizeof(*bw), GFP_KERNEL);
 666         if (!bw)
 667                 return -ENOMEM;
 668
 669         ret = of_property_read_u32_array(np, name, bw, count);
 670         if (ret) {
 671                 pr_err("%s: Error parsing %s: %d\n", __func__, name, ret);
 672                 goto out;
 673         }
 674
 675         for (i = 0; i < count; i++) {
 676                 if (peak)
 677                         new_opp->bandwidth[i].peak = kBps_to_icc(bw[i]);
 678                 else
 679                         new_opp->bandwidth[i].avg = kBps_to_icc(bw[i]);
 680         }
 681
 682 out:
 683         kfree(bw);
 684         return ret;
 685 }
 686
 687 static int _read_opp_key(struct dev_pm_opp *new_opp, struct opp_table *table,
 688                          struct device_node *np, bool *rate_not_available)
 689 {
 690         bool found = false;
 691         u64 rate;
 692         int ret;
 693
 694         ret = of_property_read_u64(np, "opp-hz", &rate);
 695         if (!ret) {
 696                 /*
 697                  * Rate is defined as an unsigned long in clk API, and so
 698                  * casting explicitly to its type. Must be fixed once rate is 64
 699                  * bit guaranteed in clk API.
 700                  */
 701                 new_opp->rate = (unsigned long)rate;
 702                 found = true;
 703         }
 704         *rate_not_available = !!ret;
 705
 706         /*
 707          * Bandwidth consists of peak and average (optional) values:
 708          * opp-peak-kBps = <path1_value path2_value>;
 709          * opp-avg-kBps = <path1_value path2_value>;
 710          */
 711         ret = _read_bw(new_opp, table, np, true);
 712         if (!ret) {
 713                 found = true;
 714                 ret = _read_bw(new_opp, table, np, false);
 715         }
 716
 717         /* The properties were found but we failed to parse them */
 718         if (ret && ret != -ENODEV)
 719                 return ret;
 720
 721         if (!of_property_read_u32(np, "opp-level", &new_opp->level))
 722                 found = true;
 723
 724         if (found)
 725                 return 0;
 726
 727         return ret;
 728 }
 729
 730 /**
 731  * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings)
 732  * @opp_table:  OPP table
 733  * @dev:        device for which we do this operation
 734  * @np:         device node
 735  *
 736  * This function adds an opp definition to the opp table and returns status. The
 737  * opp can be controlled using dev_pm_opp_enable/disable functions and may be
 738  * removed by dev_pm_opp_remove.
 739  *
 740  * Return:
 741  * Valid OPP pointer:
 742  *              On success
 743  * NULL:
 744  *              Duplicate OPPs (both freq and volt are same) and opp->available
 745  *              OR if the OPP is not supported by hardware.
 746  * ERR_PTR(-EEXIST):
 747  *              Freq are same and volt are different OR
 748  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 749  * ERR_PTR(-ENOMEM):
 750  *              Memory allocation failure
 751  * ERR_PTR(-EINVAL):
 752  *              Failed parsing the OPP node
 753  */
 754 static struct dev_pm_opp *_opp_add_static_v2(struct opp_table *opp_table,
 755                 struct device *dev, struct device_node *np)
 756 {
 757         struct dev_pm_opp *new_opp;
 758         u64 rate = 0;
 759         u32 val;
 760         int ret;
 761         bool rate_not_available = false;
 762
 763         new_opp = _opp_allocate(opp_table);
 764         if (!new_opp)
 765                 return ERR_PTR(-ENOMEM);
 766
 767         ret = _read_opp_key(new_opp, opp_table, np, &rate_not_available);
 768         if (ret < 0 && !opp_table->is_genpd) {
 769                 dev_err(dev, "%s: opp key field not found\n", __func__);
 770                 goto free_opp;
 771         }
 772
 773         /* Check if the OPP supports hardware's hierarchy of versions or not */
 774         if (!_opp_is_supported(dev, opp_table, np)) {
 775                 dev_dbg(dev, "OPP not supported by hardware: %llu\n", rate);
 776                 goto free_opp;
 777         }
 778
 779         new_opp->turbo = of_property_read_bool(np, "turbo-mode");
 780
 781         new_opp->np = np;
 782         new_opp->dynamic = false;
 783         new_opp->available = true;
 784
 785         ret = _of_opp_alloc_required_opps(opp_table, new_opp);
 786         if (ret)
 787                 goto free_opp;
 788
 789         if (!of_property_read_u32(np, "clock-latency-ns", &val))
 790                 new_opp->clock_latency_ns = val;
 791
 792         ret = opp_parse_supplies(new_opp, dev, opp_table);
 793         if (ret)
 794                 goto free_required_opps;
 795
 796         if (opp_table->is_genpd)
 797                 new_opp->pstate = pm_genpd_opp_to_performance_state(dev, new_opp);
 798
 799         ret = _opp_add(dev, new_opp, opp_table, rate_not_available);
 800         if (ret) {
 801                 /* Don't return error for duplicate OPPs */
 802                 if (ret == -EBUSY)
 803                         ret = 0;
 804                 goto free_required_opps;
 805         }
 806
 807         /* OPP to select on device suspend */
 808         if (of_property_read_bool(np, "opp-suspend")) {
 809                 if (opp_table->suspend_opp) {
 810                         /* Pick the OPP with higher rate as suspend OPP */
 811                         if (new_opp->rate > opp_table->suspend_opp->rate) {
 812                                 opp_table->suspend_opp->suspend = false;
 813                                 new_opp->suspend = true;
 814                                 opp_table->suspend_opp = new_opp;
 815                         }
 816                 } else {
 817                         new_opp->suspend = true;
 818                         opp_table->suspend_opp = new_opp;
 819                 }
 820         }
 821
 822         if (new_opp->clock_latency_ns > opp_table->clock_latency_ns_max)
 823                 opp_table->clock_latency_ns_max = new_opp->clock_latency_ns;
 824
 825         pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu\n",
 826                  __func__, new_opp->turbo, new_opp->rate,
 827                  new_opp->supplies[0].u_volt, new_opp->supplies[0].u_volt_min,
 828                  new_opp->supplies[0].u_volt_max, new_opp->clock_latency_ns);
 829
 830         /*
 831          * Notify the changes in the availability of the operable
 832          * frequency/voltage list.
 833          */
 834         blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ADD, new_opp);
 835         return new_opp;
 836
 837 free_required_opps:
 838         _of_opp_free_required_opps(opp_table, new_opp);
 839 free_opp:
 840         _opp_free(new_opp);
 841
 842         return ERR_PTR(ret);
 843 }
 844
 845 /* Initializes OPP tables based on new bindings */
 846 static int _of_add_opp_table_v2(struct device *dev, struct opp_table *opp_table)
 847 {
 848         struct device_node *np;
 849         int ret, count = 0;
 850         struct dev_pm_opp *opp;
 851
 852         /* OPP table is already initialized for the device */
 853         mutex_lock(&opp_table->lock);
 854         if (opp_table->parsed_static_opps) {
 855                 opp_table->parsed_static_opps++;
 856                 mutex_unlock(&opp_table->lock);
 857                 return 0;
 858         }
 859
 860         opp_table->parsed_static_opps = 1;
 861         mutex_unlock(&opp_table->lock);
 862
 863         /* We have opp-table node now, iterate over it and add OPPs */
 864         for_each_available_child_of_node(opp_table->np, np) {
 865                 opp = _opp_add_static_v2(opp_table, dev, np);
 866                 if (IS_ERR(opp)) {
 867                         ret = PTR_ERR(opp);
 868                         dev_err(dev, "%s: Failed to add OPP, %d\n", __func__,
 869                                 ret);
 870                         of_node_put(np);
 871                         goto remove_static_opp;
 872                 } else if (opp) {
 873                         count++;
 874                 }
 875         }
 876
 877         /* There should be one of more OPP defined */
 878         if (WARN_ON(!count)) {
 879                 ret = -ENOENT;
 880                 goto remove_static_opp;
 881         }
 882
 883         list_for_each_entry(opp, &opp_table->opp_list, node) {
 884                 /* Any non-zero performance state would enable the feature */
 885                 if (opp->pstate) {
 886                         opp_table->genpd_performance_state = true;
 887                         break;
 888                 }
 889         }
 890
 891         return 0;
 892
 893 remove_static_opp:
 894         _opp_remove_all_static(opp_table);
 895
 896         return ret;
 897 }
 898
 899 /* Initializes OPP tables based on old-deprecated bindings */
 900 static int _of_add_opp_table_v1(struct device *dev, struct opp_table *opp_table)
 901 {
 902         const struct property *prop;
 903         const __be32 *val;
 904         int nr, ret = 0;
 905
 906         mutex_lock(&opp_table->lock);
 907         if (opp_table->parsed_static_opps) {
 908                 opp_table->parsed_static_opps++;
 909                 mutex_unlock(&opp_table->lock);
 910                 return 0;
 911         }
 912
 913         opp_table->parsed_static_opps = 1;
 914         mutex_unlock(&opp_table->lock);
 915
 916         prop = of_find_property(dev->of_node, "operating-points", NULL);
 917         if (!prop) {
 918                 ret = -ENODEV;
 919                 goto remove_static_opp;
 920         }
 921         if (!prop->value) {
 922                 ret = -ENODATA;
 923                 goto remove_static_opp;
 924         }
 925
 926         /*
 927          * Each OPP is a set of tuples consisting of frequency and
 928          * voltage like <freq-kHz vol-uV>.
 929          */
 930         nr = prop->length / sizeof(u32);
 931         if (nr % 2) {
 932                 dev_err(dev, "%s: Invalid OPP table\n", __func__);
 933                 ret = -EINVAL;
 934                 goto remove_static_opp;
 935         }
 936
 937         val = prop->value;
 938         while (nr) {
 939                 unsigned long freq = be32_to_cpup(val++) * 1000;
 940                 unsigned long volt = be32_to_cpup(val++);
 941
 942                 ret = _opp_add_v1(opp_table, dev, freq, volt, false);
 943                 if (ret) {
 944                         dev_err(dev, "%s: Failed to add OPP %ld (%d)\n",
 945                                 __func__, freq, ret);
 946                         goto remove_static_opp;
 947                 }
 948                 nr -= 2;
 949         }
 950
 951         return 0;
 952
 953 remove_static_opp:
 954         _opp_remove_all_static(opp_table);
 955
 956         return ret;
 957 }
 958
 959 /**
 960  * dev_pm_opp_of_add_table() - Initialize opp table from device tree
 961  * @dev:        device pointer used to lookup OPP table.
 962  *
 963  * Register the initial OPP table with the OPP library for given device.
 964  *
 965  * Return:
 966  * 0            On success OR
 967  *              Duplicate OPPs (both freq and volt are same) and opp->available
 968  * -EEXIST      Freq are same and volt are different OR
 969  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 970  * -ENOMEM      Memory allocation failure
 971  * -ENODEV      when 'operating-points' property is not found or is invalid data
 972  *              in device node.
 973  * -ENODATA     when empty 'operating-points' property is found
 974  * -EINVAL      when invalid entries are found in opp-v2 table
 975  */
 976 int dev_pm_opp_of_add_table(struct device *dev)
 977 {
 978         struct opp_table *opp_table;
 979         int ret;
 980
 981         opp_table = _add_opp_table_indexed(dev, 0);
 982         if (IS_ERR(opp_table))
 983                 return PTR_ERR(opp_table);
 984
 985         /*
 986          * OPPs have two version of bindings now. Also try the old (v1)
 987          * bindings for backward compatibility with older dtbs.
 988          */
 989         if (opp_table->np)
 990                 ret = _of_add_opp_table_v2(dev, opp_table);
 991         else
 992                 ret = _of_add_opp_table_v1(dev, opp_table);
 993
 994         if (ret)
 995                 dev_pm_opp_put_opp_table(opp_table);
 996
 997         return ret;
 998 }
 999 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table);
1000
1001 /**
1002  * dev_pm_opp_of_add_table_indexed() - Initialize indexed opp table from device tree
1003  * @dev:        device pointer used to lookup OPP table.
1004  * @index:      Index number.
1005  *
1006  * Register the initial OPP table with the OPP library for given device only
1007  * using the "operating-points-v2" property.
1008  *
1009  * Return:
1010  * 0            On success OR
1011  *              Duplicate OPPs (both freq and volt are same) and opp->available
1012  * -EEXIST      Freq are same and volt are different OR
1013  *              Duplicate OPPs (both freq and volt are same) and !opp->available
1014  * -ENOMEM      Memory allocation failure
1015  * -ENODEV      when 'operating-points' property is not found or is invalid data
1016  *              in device node.
1017  * -ENODATA     when empty 'operating-points' property is found
1018  * -EINVAL      when invalid entries are found in opp-v2 table
1019  */
1020 int dev_pm_opp_of_add_table_indexed(struct device *dev, int index)
1021 {
1022         struct opp_table *opp_table;
1023         int ret, count;
1024
1025         if (index) {
1026                 /*
1027                  * If only one phandle is present, then the same OPP table
1028                  * applies for all index requests.
1029                  */
1030                 count = of_count_phandle_with_args(dev->of_node,
1031                                                    "operating-points-v2", NULL);
1032                 if (count == 1)
1033                         index = 0;
1034         }
1035
1036         opp_table = _add_opp_table_indexed(dev, index);
1037         if (IS_ERR(opp_table))
1038                 return PTR_ERR(opp_table);
1039
1040         ret = _of_add_opp_table_v2(dev, opp_table);
1041         if (ret)
1042                 dev_pm_opp_put_opp_table(opp_table);
1043
1044         return ret;
1045 }
1046 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table_indexed);
1047
1048 /* CPU device specific helpers */
1049
1050 /**
1051  * dev_pm_opp_of_cpumask_remove_table() - Removes OPP table for @cpumask
1052  * @cpumask:    cpumask for which OPP table needs to be removed
1053  *
1054  * This removes the OPP tables for CPUs present in the @cpumask.
1055  * This should be used only to remove static entries created from DT.
1056  */
1057 void dev_pm_opp_of_cpumask_remove_table(const struct cpumask *cpumask)
1058 {
1059         _dev_pm_opp_cpumask_remove_table(cpumask, -1);
1060 }
1061 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_remove_table);
1062
1063 /**
1064  * dev_pm_opp_of_cpumask_add_table() - Adds OPP table for @cpumask
1065  * @cpumask:    cpumask for which OPP table needs to be added.
1066  *
1067  * This adds the OPP tables for CPUs present in the @cpumask.
1068  */
1069 int dev_pm_opp_of_cpumask_add_table(const struct cpumask *cpumask)
1070 {
1071         struct device *cpu_dev;
1072         int cpu, ret;
1073
1074         if (WARN_ON(cpumask_empty(cpumask)))
1075                 return -ENODEV;
1076
1077         for_each_cpu(cpu, cpumask) {
1078                 cpu_dev = get_cpu_device(cpu);
1079                 if (!cpu_dev) {
1080                         pr_err("%s: failed to get cpu%d device\n", __func__,
1081                                cpu);
1082                         ret = -ENODEV;
1083                         goto remove_table;
1084                 }
1085
1086                 ret = dev_pm_opp_of_add_table(cpu_dev);
1087                 if (ret) {
1088                         /*
1089                          * OPP may get registered dynamically, don't print error
1090                          * message here.
1091                          */
1092                         pr_debug("%s: couldn't find opp table for cpu:%d, %d\n",
1093                                  __func__, cpu, ret);
1094
1095                         goto remove_table;
1096                 }
1097         }
1098
1099         return 0;
1100
1101 remove_table:
1102         /* Free all other OPPs */
1103         _dev_pm_opp_cpumask_remove_table(cpumask, cpu);
1104
1105         return ret;
1106 }
1107 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_add_table);
1108
1109 /*
1110  * Works only for OPP v2 bindings.
1111  *
1112  * Returns -ENOENT if operating-points-v2 bindings aren't supported.
1113  */
1114 /**
1115  * dev_pm_opp_of_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with
1116  *                                    @cpu_dev using operating-points-v2
1117  *                                    bindings.
1118  *
1119  * @cpu_dev:    CPU device for which we do this operation
1120  * @cpumask:    cpumask to update with information of sharing CPUs
1121  *
1122  * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev.
1123  *
1124  * Returns -ENOENT if operating-points-v2 isn't present for @cpu_dev.
1125  */
1126 int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev,
1127                                    struct cpumask *cpumask)
1128 {
1129         struct device_node *np, *tmp_np, *cpu_np;
1130         int cpu, ret = 0;
1131
1132         /* Get OPP descriptor node */
1133         np = dev_pm_opp_of_get_opp_desc_node(cpu_dev);
1134         if (!np) {
1135                 dev_dbg(cpu_dev, "%s: Couldn't find opp node.\n", __func__);
1136                 return -ENOENT;
1137         }
1138
1139         cpumask_set_cpu(cpu_dev->id, cpumask);
1140
1141         /* OPPs are shared ? */
1142         if (!of_property_read_bool(np, "opp-shared"))
1143                 goto put_cpu_node;
1144
1145         for_each_possible_cpu(cpu) {
1146                 if (cpu == cpu_dev->id)
1147                         continue;
1148
1149                 cpu_np = of_cpu_device_node_get(cpu);
1150                 if (!cpu_np) {
1151                         dev_err(cpu_dev, "%s: failed to get cpu%d node\n",
1152                                 __func__, cpu);
1153                         ret = -ENOENT;
1154                         goto put_cpu_node;
1155                 }
1156
1157                 /* Get OPP descriptor node */
1158                 tmp_np = _opp_of_get_opp_desc_node(cpu_np, 0);
1159                 of_node_put(cpu_np);
1160                 if (!tmp_np) {
1161                         pr_err("%pOF: Couldn't find opp node\n", cpu_np);
1162                         ret = -ENOENT;
1163                         goto put_cpu_node;
1164                 }
1165
1166                 /* CPUs are sharing opp node */
1167                 if (np == tmp_np)
1168                         cpumask_set_cpu(cpu, cpumask);
1169
1170                 of_node_put(tmp_np);
1171         }
1172
1173 put_cpu_node:
1174         of_node_put(np);
1175         return ret;
1176 }
1177 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus);
1178
1179 /**
1180  * of_get_required_opp_performance_state() - Search for required OPP and return its performance state.
1181  * @np: Node that contains the "required-opps" property.
1182  * @index: Index of the phandle to parse.
1183  *
1184  * Returns the performance state of the OPP pointed out by the "required-opps"
1185  * property at @index in @np.
1186  *
1187  * Return: Zero or positive performance state on success, otherwise negative
1188  * value on errors.
1189  */
1190 int of_get_required_opp_performance_state(struct device_node *np, int index)
1191 {
1192         struct dev_pm_opp *opp;
1193         struct device_node *required_np;
1194         struct opp_table *opp_table;
1195         int pstate = -EINVAL;
1196
1197         required_np = of_parse_required_opp(np, index);
1198         if (!required_np)
1199                 return -EINVAL;
1200
1201         opp_table = _find_table_of_opp_np(required_np);
1202         if (IS_ERR(opp_table)) {
1203                 pr_err("%s: Failed to find required OPP table %pOF: %ld\n",
1204                        __func__, np, PTR_ERR(opp_table));
1205                 goto put_required_np;
1206         }
1207
1208         opp = _find_opp_of_np(opp_table, required_np);
1209         if (opp) {
1210                 pstate = opp->pstate;
1211                 dev_pm_opp_put(opp);
1212         }
1213
1214         dev_pm_opp_put_opp_table(opp_table);
1215
1216 put_required_np:
1217         of_node_put(required_np);
1218
1219         return pstate;
1220 }
1221 EXPORT_SYMBOL_GPL(of_get_required_opp_performance_state);
1222
1223 /**
1224  * dev_pm_opp_get_of_node() - Gets the DT node corresponding to an opp
1225  * @opp:        opp for which DT node has to be returned for
1226  *
1227  * Return: DT node corresponding to the opp, else 0 on success.
1228  *
1229  * The caller needs to put the node with of_node_put() after using it.
1230  */
1231 struct device_node *dev_pm_opp_get_of_node(struct dev_pm_opp *opp)
1232 {
1233         if (IS_ERR_OR_NULL(opp)) {
1234                 pr_err("%s: Invalid parameters\n", __func__);
1235                 return NULL;
1236         }
1237
1238         return of_node_get(opp->np);
1239 }
1240 EXPORT_SYMBOL_GPL(dev_pm_opp_get_of_node);
1241
1242 /*
1243  * Callback function provided to the Energy Model framework upon registration.
1244  * This computes the power estimated by @dev at @kHz if it is the frequency
1245  * of an existing OPP, or at the frequency of the first OPP above @kHz otherwise
1246  * (see dev_pm_opp_find_freq_ceil()). This function updates @kHz to the ceiled
1247  * frequency and @mW to the associated power. The power is estimated as
1248  * P = C * V^2 * f with C being the device's capacitance and V and f
1249  * respectively the voltage and frequency of the OPP.
1250  *
1251  * Returns -EINVAL if the power calculation failed because of missing
1252  * parameters, 0 otherwise.
1253  */
1254 static int __maybe_unused _get_power(unsigned long *mW, unsigned long *kHz,
1255                                      struct device *dev)
1256 {
1257         struct dev_pm_opp *opp;
1258         struct device_node *np;
1259         unsigned long mV, Hz;
1260         u32 cap;
1261         u64 tmp;
1262         int ret;
1263
1264         np = of_node_get(dev->of_node);
1265         if (!np)
1266                 return -EINVAL;
1267
1268         ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1269         of_node_put(np);
1270         if (ret)
1271                 return -EINVAL;
1272
1273         Hz = *kHz * 1000;
1274         opp = dev_pm_opp_find_freq_ceil(dev, &Hz);
1275         if (IS_ERR(opp))
1276                 return -EINVAL;
1277
1278         mV = dev_pm_opp_get_voltage(opp) / 1000;
1279         dev_pm_opp_put(opp);
1280         if (!mV)
1281                 return -EINVAL;
1282
1283         tmp = (u64)cap * mV * mV * (Hz / 1000000);
1284         do_div(tmp, 1000000000);
1285
1286         *mW = (unsigned long)tmp;
1287         *kHz = Hz / 1000;
1288
1289         return 0;
1290 }
1291
1292 /**
1293  * dev_pm_opp_of_register_em() - Attempt to register an Energy Model
1294  * @dev         : Device for which an Energy Model has to be registered
1295  * @cpus        : CPUs for which an Energy Model has to be registered. For
1296  *              other type of devices it should be set to NULL.
1297  *
1298  * This checks whether the "dynamic-power-coefficient" devicetree property has
1299  * been specified, and tries to register an Energy Model with it if it has.
1300  * Having this property means the voltages are known for OPPs and the EM
1301  * might be calculated.
1302  */
1303 int dev_pm_opp_of_register_em(struct device *dev, struct cpumask *cpus)
1304 {
1305         struct em_data_callback em_cb = EM_DATA_CB(_get_power);
1306         struct device_node *np;
1307         int ret, nr_opp;
1308         u32 cap;
1309
1310         if (IS_ERR_OR_NULL(dev)) {
1311                 ret = -EINVAL;
1312                 goto failed;
1313         }
1314
1315         nr_opp = dev_pm_opp_get_opp_count(dev);
1316         if (nr_opp <= 0) {
1317                 ret = -EINVAL;
1318                 goto failed;
1319         }
1320
1321         np = of_node_get(dev->of_node);
1322         if (!np) {
1323                 ret = -EINVAL;
1324                 goto failed;
1325         }
1326
1327         /*
1328          * Register an EM only if the 'dynamic-power-coefficient' property is
1329          * set in devicetree. It is assumed the voltage values are known if that
1330          * property is set since it is useless otherwise. If voltages are not
1331          * known, just let the EM registration fail with an error to alert the
1332          * user about the inconsistent configuration.
1333          */
1334         ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1335         of_node_put(np);
1336         if (ret || !cap) {
1337                 dev_dbg(dev, "Couldn't find proper 'dynamic-power-coefficient' in DT\n");
1338                 ret = -EINVAL;
1339                 goto failed;
1340         }
1341
1342         ret = em_dev_register_perf_domain(dev, nr_opp, &em_cb, cpus, true);
1343         if (ret)
1344                 goto failed;
1345
1346         return 0;
1347
1348 failed:
1349         dev_dbg(dev, "Couldn't register Energy Model %d\n", ret);
1350         return ret;
1351 }
1352 EXPORT_SYMBOL_GPL(dev_pm_opp_of_register_em);