drivers/opp/of.c

   1 /*
   2  * Generic OPP OF helpers
   3  *
   4  * Copyright (C) 2009-2010 Texas Instruments Incorporated.
   5  *      Nishanth Menon
   6  *      Romit Dasgupta
   7  *      Kevin Hilman
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  */
  13
  14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  15
  16 #include <linux/cpu.h>
  17 #include <linux/errno.h>
  18 #include <linux/device.h>
  19 #include <linux/of_device.h>
  20 #include <linux/pm_domain.h>
  21 #include <linux/slab.h>
  22 #include <linux/export.h>
  23 #include <linux/energy_model.h>
  24
  25 #include "opp.h"
  26
  27 /*
  28  * Returns opp descriptor node for a device node, caller must
  29  * do of_node_put().
  30  */
  31 static struct device_node *_opp_of_get_opp_desc_node(struct device_node *np,
  32                                                      int index)
  33 {
  34         /* "operating-points-v2" can be an array for power domain providers */
  35         return of_parse_phandle(np, "operating-points-v2", index);
  36 }
  37
  38 /* Returns opp descriptor node for a device, caller must do of_node_put() */
  39 struct device_node *dev_pm_opp_of_get_opp_desc_node(struct device *dev)
  40 {
  41         return _opp_of_get_opp_desc_node(dev->of_node, 0);
  42 }
  43 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_opp_desc_node);
  44
  45 struct opp_table *_managed_opp(struct device *dev, int index)
  46 {
  47         struct opp_table *opp_table, *managed_table = NULL;
  48         struct device_node *np;
  49
  50         np = _opp_of_get_opp_desc_node(dev->of_node, index);
  51         if (!np)
  52                 return NULL;
  53
  54         list_for_each_entry(opp_table, &opp_tables, node) {
  55                 if (opp_table->np == np) {
  56                         /*
  57                          * Multiple devices can point to the same OPP table and
  58                          * so will have same node-pointer, np.
  59                          *
  60                          * But the OPPs will be considered as shared only if the
  61                          * OPP table contains a "opp-shared" property.
  62                          */
  63                         if (opp_table->shared_opp == OPP_TABLE_ACCESS_SHARED) {
  64                                 _get_opp_table_kref(opp_table);
  65                                 managed_table = opp_table;
  66                         }
  67
  68                         break;
  69                 }
  70         }
  71
  72         of_node_put(np);
  73
  74         return managed_table;
  75 }
  76
  77 /* The caller must call dev_pm_opp_put() after the OPP is used */
  78 static struct dev_pm_opp *_find_opp_of_np(struct opp_table *opp_table,
  79                                           struct device_node *opp_np)
  80 {
  81         struct dev_pm_opp *opp;
  82
  83         lockdep_assert_held(&opp_table_lock);
  84
  85         mutex_lock(&opp_table->lock);
  86
  87         list_for_each_entry(opp, &opp_table->opp_list, node) {
  88                 if (opp->np == opp_np) {
  89                         dev_pm_opp_get(opp);
  90                         mutex_unlock(&opp_table->lock);
  91                         return opp;
  92                 }
  93         }
  94
  95         mutex_unlock(&opp_table->lock);
  96
  97         return NULL;
  98 }
  99
 100 static struct device_node *of_parse_required_opp(struct device_node *np,
 101                                                  int index)
 102 {
 103         struct device_node *required_np;
 104
 105         required_np = of_parse_phandle(np, "required-opps", index);
 106         if (unlikely(!required_np)) {
 107                 pr_err("%s: Unable to parse required-opps: %pOF, index: %d\n",
 108                        __func__, np, index);
 109         }
 110
 111         return required_np;
 112 }
 113
 114 /* The caller must call dev_pm_opp_put_opp_table() after the table is used */
 115 static struct opp_table *_find_table_of_opp_np(struct device_node *opp_np)
 116 {
 117         struct opp_table *opp_table;
 118         struct device_node *opp_table_np;
 119
 120         lockdep_assert_held(&opp_table_lock);
 121
 122         opp_table_np = of_get_parent(opp_np);
 123         if (!opp_table_np)
 124                 goto err;
 125
 126         /* It is safe to put the node now as all we need now is its address */
 127         of_node_put(opp_table_np);
 128
 129         list_for_each_entry(opp_table, &opp_tables, node) {
 130                 if (opp_table_np == opp_table->np) {
 131                         _get_opp_table_kref(opp_table);
 132                         return opp_table;
 133                 }
 134         }
 135
 136 err:
 137         return ERR_PTR(-ENODEV);
 138 }
 139
 140 /* Free resources previously acquired by _opp_table_alloc_required_tables() */
 141 static void _opp_table_free_required_tables(struct opp_table *opp_table)
 142 {
 143         struct opp_table **required_opp_tables = opp_table->required_opp_tables;
 144         struct device **genpd_virt_devs = opp_table->genpd_virt_devs;
 145         int i;
 146
 147         if (!required_opp_tables)
 148                 return;
 149
 150         for (i = 0; i < opp_table->required_opp_count; i++) {
 151                 if (IS_ERR_OR_NULL(required_opp_tables[i]))
 152                         break;
 153
 154                 dev_pm_opp_put_opp_table(required_opp_tables[i]);
 155         }
 156
 157         kfree(required_opp_tables);
 158         kfree(genpd_virt_devs);
 159
 160         opp_table->required_opp_count = 0;
 161         opp_table->genpd_virt_devs = NULL;
 162         opp_table->required_opp_tables = NULL;
 163 }
 164
 165 /*
 166  * Populate all devices and opp tables which are part of "required-opps" list.
 167  * Checking only the first OPP node should be enough.
 168  */
 169 static void _opp_table_alloc_required_tables(struct opp_table *opp_table,
 170                                              struct device *dev,
 171                                              struct device_node *opp_np)
 172 {
 173         struct opp_table **required_opp_tables;
 174         struct device **genpd_virt_devs = NULL;
 175         struct device_node *required_np, *np;
 176         int count, count_pd, i;
 177
 178         /* Traversing the first OPP node is all we need */
 179         np = of_get_next_available_child(opp_np, NULL);
 180         if (!np) {
 181                 dev_err(dev, "Empty OPP table\n");
 182                 return;
 183         }
 184
 185         count = of_count_phandle_with_args(np, "required-opps", NULL);
 186         if (!count)
 187                 goto put_np;
 188
 189         /*
 190          * Check the number of power-domains to know if we need to deal
 191          * with virtual devices. In some cases we have devices with multiple
 192          * power domains but with only one of them being scalable, hence
 193          * 'count' could be 1, but we still have to deal with multiple genpds
 194          * and virtual devices.
 195          */
 196         count_pd = of_count_phandle_with_args(dev->of_node, "power-domains",
 197                                               "#power-domain-cells");
 198         if (!count_pd)
 199                 goto put_np;
 200
 201         if (count_pd > 1) {
 202                 genpd_virt_devs = kcalloc(count, sizeof(*genpd_virt_devs),
 203                                         GFP_KERNEL);
 204                 if (!genpd_virt_devs)
 205                         goto put_np;
 206         }
 207
 208         required_opp_tables = kcalloc(count, sizeof(*required_opp_tables),
 209                                       GFP_KERNEL);
 210         if (!required_opp_tables) {
 211                 kfree(genpd_virt_devs);
 212                 goto put_np;
 213         }
 214
 215         opp_table->genpd_virt_devs = genpd_virt_devs;
 216         opp_table->required_opp_tables = required_opp_tables;
 217         opp_table->required_opp_count = count;
 218
 219         for (i = 0; i < count; i++) {
 220                 required_np = of_parse_required_opp(np, i);
 221                 if (!required_np)
 222                         goto free_required_tables;
 223
 224                 required_opp_tables[i] = _find_table_of_opp_np(required_np);
 225                 of_node_put(required_np);
 226
 227                 if (IS_ERR(required_opp_tables[i]))
 228                         goto free_required_tables;
 229
 230                 /*
 231                  * We only support genpd's OPPs in the "required-opps" for now,
 232                  * as we don't know how much about other cases. Error out if the
 233                  * required OPP doesn't belong to a genpd.
 234                  */
 235                 if (!required_opp_tables[i]->is_genpd) {
 236                         dev_err(dev, "required-opp doesn't belong to genpd: %pOF\n",
 237                                 required_np);
 238                         goto free_required_tables;
 239                 }
 240         }
 241
 242         goto put_np;
 243
 244 free_required_tables:
 245         _opp_table_free_required_tables(opp_table);
 246 put_np:
 247         of_node_put(np);
 248 }
 249
 250 void _of_init_opp_table(struct opp_table *opp_table, struct device *dev,
 251                         int index)
 252 {
 253         struct device_node *np, *opp_np;
 254         u32 val;
 255
 256         /*
 257          * Only required for backward compatibility with v1 bindings, but isn't
 258          * harmful for other cases. And so we do it unconditionally.
 259          */
 260         np = of_node_get(dev->of_node);
 261         if (!np)
 262                 return;
 263
 264         if (!of_property_read_u32(np, "clock-latency", &val))
 265                 opp_table->clock_latency_ns_max = val;
 266         of_property_read_u32(np, "voltage-tolerance",
 267                              &opp_table->voltage_tolerance_v1);
 268
 269         if (of_find_property(np, "#power-domain-cells", NULL))
 270                 opp_table->is_genpd = true;
 271
 272         /* Get OPP table node */
 273         opp_np = _opp_of_get_opp_desc_node(np, index);
 274         of_node_put(np);
 275
 276         if (!opp_np)
 277                 return;
 278
 279         if (of_property_read_bool(opp_np, "opp-shared"))
 280                 opp_table->shared_opp = OPP_TABLE_ACCESS_SHARED;
 281         else
 282                 opp_table->shared_opp = OPP_TABLE_ACCESS_EXCLUSIVE;
 283
 284         opp_table->np = opp_np;
 285
 286         _opp_table_alloc_required_tables(opp_table, dev, opp_np);
 287         of_node_put(opp_np);
 288 }
 289
 290 void _of_clear_opp_table(struct opp_table *opp_table)
 291 {
 292         _opp_table_free_required_tables(opp_table);
 293 }
 294
 295 /*
 296  * Release all resources previously acquired with a call to
 297  * _of_opp_alloc_required_opps().
 298  */
 299 void _of_opp_free_required_opps(struct opp_table *opp_table,
 300                                 struct dev_pm_opp *opp)
 301 {
 302         struct dev_pm_opp **required_opps = opp->required_opps;
 303         int i;
 304
 305         if (!required_opps)
 306                 return;
 307
 308         for (i = 0; i < opp_table->required_opp_count; i++) {
 309                 if (!required_opps[i])
 310                         break;
 311
 312                 /* Put the reference back */
 313                 dev_pm_opp_put(required_opps[i]);
 314         }
 315
 316         kfree(required_opps);
 317         opp->required_opps = NULL;
 318 }
 319
 320 /* Populate all required OPPs which are part of "required-opps" list */
 321 static int _of_opp_alloc_required_opps(struct opp_table *opp_table,
 322                                        struct dev_pm_opp *opp)
 323 {
 324         struct dev_pm_opp **required_opps;
 325         struct opp_table *required_table;
 326         struct device_node *np;
 327         int i, ret, count = opp_table->required_opp_count;
 328
 329         if (!count)
 330                 return 0;
 331
 332         required_opps = kcalloc(count, sizeof(*required_opps), GFP_KERNEL);
 333         if (!required_opps)
 334                 return -ENOMEM;
 335
 336         opp->required_opps = required_opps;
 337
 338         for (i = 0; i < count; i++) {
 339                 required_table = opp_table->required_opp_tables[i];
 340
 341                 np = of_parse_required_opp(opp->np, i);
 342                 if (unlikely(!np)) {
 343                         ret = -ENODEV;
 344                         goto free_required_opps;
 345                 }
 346
 347                 required_opps[i] = _find_opp_of_np(required_table, np);
 348                 of_node_put(np);
 349
 350                 if (!required_opps[i]) {
 351                         pr_err("%s: Unable to find required OPP node: %pOF (%d)\n",
 352                                __func__, opp->np, i);
 353                         ret = -ENODEV;
 354                         goto free_required_opps;
 355                 }
 356         }
 357
 358         return 0;
 359
 360 free_required_opps:
 361         _of_opp_free_required_opps(opp_table, opp);
 362
 363         return ret;
 364 }
 365
 366 static bool _opp_is_supported(struct device *dev, struct opp_table *opp_table,
 367                               struct device_node *np)
 368 {
 369         unsigned int count = opp_table->supported_hw_count;
 370         u32 version;
 371         int ret;
 372
 373         if (!opp_table->supported_hw) {
 374                 /*
 375                  * In the case that no supported_hw has been set by the
 376                  * platform but there is an opp-supported-hw value set for
 377                  * an OPP then the OPP should not be enabled as there is
 378                  * no way to see if the hardware supports it.
 379                  */
 380                 if (of_find_property(np, "opp-supported-hw", NULL))
 381                         return false;
 382                 else
 383                         return true;
 384         }
 385
 386         while (count--) {
 387                 ret = of_property_read_u32_index(np, "opp-supported-hw", count,
 388                                                  &version);
 389                 if (ret) {
 390                         dev_warn(dev, "%s: failed to read opp-supported-hw property at index %d: %d\n",
 391                                  __func__, count, ret);
 392                         return false;
 393                 }
 394
 395                 /* Both of these are bitwise masks of the versions */
 396                 if (!(version & opp_table->supported_hw[count]))
 397                         return false;
 398         }
 399
 400         return true;
 401 }
 402
 403 static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,
 404                               struct opp_table *opp_table)
 405 {
 406         u32 *microvolt, *microamp = NULL;
 407         int supplies = opp_table->regulator_count, vcount, icount, ret, i, j;
 408         struct property *prop = NULL;
 409         char name[NAME_MAX];
 410
 411         /* Search for "opp-microvolt-<name>" */
 412         if (opp_table->prop_name) {
 413                 snprintf(name, sizeof(name), "opp-microvolt-%s",
 414                          opp_table->prop_name);
 415                 prop = of_find_property(opp->np, name, NULL);
 416         }
 417
 418         if (!prop) {
 419                 /* Search for "opp-microvolt" */
 420                 sprintf(name, "opp-microvolt");
 421                 prop = of_find_property(opp->np, name, NULL);
 422
 423                 /* Missing property isn't a problem, but an invalid entry is */
 424                 if (!prop) {
 425                         if (unlikely(supplies == -1)) {
 426                                 /* Initialize regulator_count */
 427                                 opp_table->regulator_count = 0;
 428                                 return 0;
 429                         }
 430
 431                         if (!supplies)
 432                                 return 0;
 433
 434                         dev_err(dev, "%s: opp-microvolt missing although OPP managing regulators\n",
 435                                 __func__);
 436                         return -EINVAL;
 437                 }
 438         }
 439
 440         if (unlikely(supplies == -1)) {
 441                 /* Initialize regulator_count */
 442                 supplies = opp_table->regulator_count = 1;
 443         } else if (unlikely(!supplies)) {
 444                 dev_err(dev, "%s: opp-microvolt wasn't expected\n", __func__);
 445                 return -EINVAL;
 446         }
 447
 448         vcount = of_property_count_u32_elems(opp->np, name);
 449         if (vcount < 0) {
 450                 dev_err(dev, "%s: Invalid %s property (%d)\n",
 451                         __func__, name, vcount);
 452                 return vcount;
 453         }
 454
 455         /* There can be one or three elements per supply */
 456         if (vcount != supplies && vcount != supplies * 3) {
 457                 dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
 458                         __func__, name, vcount, supplies);
 459                 return -EINVAL;
 460         }
 461
 462         microvolt = kmalloc_array(vcount, sizeof(*microvolt), GFP_KERNEL);
 463         if (!microvolt)
 464                 return -ENOMEM;
 465
 466         ret = of_property_read_u32_array(opp->np, name, microvolt, vcount);
 467         if (ret) {
 468                 dev_err(dev, "%s: error parsing %s: %d\n", __func__, name, ret);
 469                 ret = -EINVAL;
 470                 goto free_microvolt;
 471         }
 472
 473         /* Search for "opp-microamp-<name>" */
 474         prop = NULL;
 475         if (opp_table->prop_name) {
 476                 snprintf(name, sizeof(name), "opp-microamp-%s",
 477                          opp_table->prop_name);
 478                 prop = of_find_property(opp->np, name, NULL);
 479         }
 480
 481         if (!prop) {
 482                 /* Search for "opp-microamp" */
 483                 sprintf(name, "opp-microamp");
 484                 prop = of_find_property(opp->np, name, NULL);
 485         }
 486
 487         if (prop) {
 488                 icount = of_property_count_u32_elems(opp->np, name);
 489                 if (icount < 0) {
 490                         dev_err(dev, "%s: Invalid %s property (%d)\n", __func__,
 491                                 name, icount);
 492                         ret = icount;
 493                         goto free_microvolt;
 494                 }
 495
 496                 if (icount != supplies) {
 497                         dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
 498                                 __func__, name, icount, supplies);
 499                         ret = -EINVAL;
 500                         goto free_microvolt;
 501                 }
 502
 503                 microamp = kmalloc_array(icount, sizeof(*microamp), GFP_KERNEL);
 504                 if (!microamp) {
 505                         ret = -EINVAL;
 506                         goto free_microvolt;
 507                 }
 508
 509                 ret = of_property_read_u32_array(opp->np, name, microamp,
 510                                                  icount);
 511                 if (ret) {
 512                         dev_err(dev, "%s: error parsing %s: %d\n", __func__,
 513                                 name, ret);
 514                         ret = -EINVAL;
 515                         goto free_microamp;
 516                 }
 517         }
 518
 519         for (i = 0, j = 0; i < supplies; i++) {
 520                 opp->supplies[i].u_volt = microvolt[j++];
 521
 522                 if (vcount == supplies) {
 523                         opp->supplies[i].u_volt_min = opp->supplies[i].u_volt;
 524                         opp->supplies[i].u_volt_max = opp->supplies[i].u_volt;
 525                 } else {
 526                         opp->supplies[i].u_volt_min = microvolt[j++];
 527                         opp->supplies[i].u_volt_max = microvolt[j++];
 528                 }
 529
 530                 if (microamp)
 531                         opp->supplies[i].u_amp = microamp[i];
 532         }
 533
 534 free_microamp:
 535         kfree(microamp);
 536 free_microvolt:
 537         kfree(microvolt);
 538
 539         return ret;
 540 }
 541
 542 /**
 543  * dev_pm_opp_of_remove_table() - Free OPP table entries created from static DT
 544  *                                entries
 545  * @dev:        device pointer used to lookup OPP table.
 546  *
 547  * Free OPPs created using static entries present in DT.
 548  */
 549 void dev_pm_opp_of_remove_table(struct device *dev)
 550 {
 551         _dev_pm_opp_find_and_remove_table(dev);
 552 }
 553 EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table);
 554
 555 /**
 556  * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings)
 557  * @opp_table:  OPP table
 558  * @dev:        device for which we do this operation
 559  * @np:         device node
 560  *
 561  * This function adds an opp definition to the opp table and returns status. The
 562  * opp can be controlled using dev_pm_opp_enable/disable functions and may be
 563  * removed by dev_pm_opp_remove.
 564  *
 565  * Return:
 566  * Valid OPP pointer:
 567  *              On success
 568  * NULL:
 569  *              Duplicate OPPs (both freq and volt are same) and opp->available
 570  *              OR if the OPP is not supported by hardware.
 571  * ERR_PTR(-EEXIST):
 572  *              Freq are same and volt are different OR
 573  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 574  * ERR_PTR(-ENOMEM):
 575  *              Memory allocation failure
 576  * ERR_PTR(-EINVAL):
 577  *              Failed parsing the OPP node
 578  */
 579 static struct dev_pm_opp *_opp_add_static_v2(struct opp_table *opp_table,
 580                 struct device *dev, struct device_node *np)
 581 {
 582         struct dev_pm_opp *new_opp;
 583         u64 rate = 0;
 584         u32 val;
 585         int ret;
 586         bool rate_not_available = false;
 587
 588         new_opp = _opp_allocate(opp_table);
 589         if (!new_opp)
 590                 return ERR_PTR(-ENOMEM);
 591
 592         ret = of_property_read_u64(np, "opp-hz", &rate);
 593         if (ret < 0) {
 594                 /* "opp-hz" is optional for devices like power domains. */
 595                 if (!opp_table->is_genpd) {
 596                         dev_err(dev, "%s: opp-hz not found\n", __func__);
 597                         goto free_opp;
 598                 }
 599
 600                 rate_not_available = true;
 601         } else {
 602                 /*
 603                  * Rate is defined as an unsigned long in clk API, and so
 604                  * casting explicitly to its type. Must be fixed once rate is 64
 605                  * bit guaranteed in clk API.
 606                  */
 607                 new_opp->rate = (unsigned long)rate;
 608         }
 609
 610         of_property_read_u32(np, "opp-level", &new_opp->level);
 611
 612         /* Check if the OPP supports hardware's hierarchy of versions or not */
 613         if (!_opp_is_supported(dev, opp_table, np)) {
 614                 dev_dbg(dev, "OPP not supported by hardware: %llu\n", rate);
 615                 goto free_opp;
 616         }
 617
 618         new_opp->turbo = of_property_read_bool(np, "turbo-mode");
 619
 620         new_opp->np = np;
 621         new_opp->dynamic = false;
 622         new_opp->available = true;
 623
 624         ret = _of_opp_alloc_required_opps(opp_table, new_opp);
 625         if (ret)
 626                 goto free_opp;
 627
 628         if (!of_property_read_u32(np, "clock-latency-ns", &val))
 629                 new_opp->clock_latency_ns = val;
 630
 631         ret = opp_parse_supplies(new_opp, dev, opp_table);
 632         if (ret)
 633                 goto free_required_opps;
 634
 635         if (opp_table->is_genpd)
 636                 new_opp->pstate = pm_genpd_opp_to_performance_state(dev, new_opp);
 637
 638         ret = _opp_add(dev, new_opp, opp_table, rate_not_available);
 639         if (ret) {
 640                 /* Don't return error for duplicate OPPs */
 641                 if (ret == -EBUSY)
 642                         ret = 0;
 643                 goto free_required_opps;
 644         }
 645
 646         /* OPP to select on device suspend */
 647         if (of_property_read_bool(np, "opp-suspend")) {
 648                 if (opp_table->suspend_opp) {
 649                         dev_warn(dev, "%s: Multiple suspend OPPs found (%lu %lu)\n",
 650                                  __func__, opp_table->suspend_opp->rate,
 651                                  new_opp->rate);
 652                 } else {
 653                         new_opp->suspend = true;
 654                         opp_table->suspend_opp = new_opp;
 655                 }
 656         }
 657
 658         if (new_opp->clock_latency_ns > opp_table->clock_latency_ns_max)
 659                 opp_table->clock_latency_ns_max = new_opp->clock_latency_ns;
 660
 661         pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu\n",
 662                  __func__, new_opp->turbo, new_opp->rate,
 663                  new_opp->supplies[0].u_volt, new_opp->supplies[0].u_volt_min,
 664                  new_opp->supplies[0].u_volt_max, new_opp->clock_latency_ns);
 665
 666         /*
 667          * Notify the changes in the availability of the operable
 668          * frequency/voltage list.
 669          */
 670         blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ADD, new_opp);
 671         return new_opp;
 672
 673 free_required_opps:
 674         _of_opp_free_required_opps(opp_table, new_opp);
 675 free_opp:
 676         _opp_free(new_opp);
 677
 678         return ERR_PTR(ret);
 679 }
 680
 681 /* Initializes OPP tables based on new bindings */
 682 static int _of_add_opp_table_v2(struct device *dev, struct opp_table *opp_table)
 683 {
 684         struct device_node *np;
 685         int ret, count = 0, pstate_count = 0;
 686         struct dev_pm_opp *opp;
 687
 688         /* OPP table is already initialized for the device */
 689         if (opp_table->parsed_static_opps) {
 690                 kref_get(&opp_table->list_kref);
 691                 return 0;
 692         }
 693
 694         kref_init(&opp_table->list_kref);
 695
 696         /* We have opp-table node now, iterate over it and add OPPs */
 697         for_each_available_child_of_node(opp_table->np, np) {
 698                 opp = _opp_add_static_v2(opp_table, dev, np);
 699                 if (IS_ERR(opp)) {
 700                         ret = PTR_ERR(opp);
 701                         dev_err(dev, "%s: Failed to add OPP, %d\n", __func__,
 702                                 ret);
 703                         of_node_put(np);
 704                         goto put_list_kref;
 705                 } else if (opp) {
 706                         count++;
 707                 }
 708         }
 709
 710         /* There should be one of more OPP defined */
 711         if (WARN_ON(!count)) {
 712                 ret = -ENOENT;
 713                 goto put_list_kref;
 714         }
 715
 716         list_for_each_entry(opp, &opp_table->opp_list, node)
 717                 pstate_count += !!opp->pstate;
 718
 719         /* Either all or none of the nodes shall have performance state set */
 720         if (pstate_count && pstate_count != count) {
 721                 dev_err(dev, "Not all nodes have performance state set (%d: %d)\n",
 722                         count, pstate_count);
 723                 ret = -ENOENT;
 724                 goto put_list_kref;
 725         }
 726
 727         if (pstate_count)
 728                 opp_table->genpd_performance_state = true;
 729
 730         opp_table->parsed_static_opps = true;
 731
 732         return 0;
 733
 734 put_list_kref:
 735         _put_opp_list_kref(opp_table);
 736
 737         return ret;
 738 }
 739
 740 /* Initializes OPP tables based on old-deprecated bindings */
 741 static int _of_add_opp_table_v1(struct device *dev, struct opp_table *opp_table)
 742 {
 743         const struct property *prop;
 744         const __be32 *val;
 745         int nr, ret = 0;
 746
 747         prop = of_find_property(dev->of_node, "operating-points", NULL);
 748         if (!prop)
 749                 return -ENODEV;
 750         if (!prop->value)
 751                 return -ENODATA;
 752
 753         /*
 754          * Each OPP is a set of tuples consisting of frequency and
 755          * voltage like <freq-kHz vol-uV>.
 756          */
 757         nr = prop->length / sizeof(u32);
 758         if (nr % 2) {
 759                 dev_err(dev, "%s: Invalid OPP table\n", __func__);
 760                 return -EINVAL;
 761         }
 762
 763         kref_init(&opp_table->list_kref);
 764
 765         val = prop->value;
 766         while (nr) {
 767                 unsigned long freq = be32_to_cpup(val++) * 1000;
 768                 unsigned long volt = be32_to_cpup(val++);
 769
 770                 ret = _opp_add_v1(opp_table, dev, freq, volt, false);
 771                 if (ret) {
 772                         dev_err(dev, "%s: Failed to add OPP %ld (%d)\n",
 773                                 __func__, freq, ret);
 774                         _put_opp_list_kref(opp_table);
 775                         return ret;
 776                 }
 777                 nr -= 2;
 778         }
 779
 780         return ret;
 781 }
 782
 783 /**
 784  * dev_pm_opp_of_add_table() - Initialize opp table from device tree
 785  * @dev:        device pointer used to lookup OPP table.
 786  *
 787  * Register the initial OPP table with the OPP library for given device.
 788  *
 789  * Return:
 790  * 0            On success OR
 791  *              Duplicate OPPs (both freq and volt are same) and opp->available
 792  * -EEXIST      Freq are same and volt are different OR
 793  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 794  * -ENOMEM      Memory allocation failure
 795  * -ENODEV      when 'operating-points' property is not found or is invalid data
 796  *              in device node.
 797  * -ENODATA     when empty 'operating-points' property is found
 798  * -EINVAL      when invalid entries are found in opp-v2 table
 799  */
 800 int dev_pm_opp_of_add_table(struct device *dev)
 801 {
 802         struct opp_table *opp_table;
 803         int ret;
 804
 805         opp_table = dev_pm_opp_get_opp_table_indexed(dev, 0);
 806         if (!opp_table)
 807                 return -ENOMEM;
 808
 809         /*
 810          * OPPs have two version of bindings now. Also try the old (v1)
 811          * bindings for backward compatibility with older dtbs.
 812          */
 813         if (opp_table->np)
 814                 ret = _of_add_opp_table_v2(dev, opp_table);
 815         else
 816                 ret = _of_add_opp_table_v1(dev, opp_table);
 817
 818         if (ret)
 819                 dev_pm_opp_put_opp_table(opp_table);
 820
 821         return ret;
 822 }
 823 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table);
 824
 825 /**
 826  * dev_pm_opp_of_add_table_indexed() - Initialize indexed opp table from device tree
 827  * @dev:        device pointer used to lookup OPP table.
 828  * @index:      Index number.
 829  *
 830  * Register the initial OPP table with the OPP library for given device only
 831  * using the "operating-points-v2" property.
 832  *
 833  * Return:
 834  * 0            On success OR
 835  *              Duplicate OPPs (both freq and volt are same) and opp->available
 836  * -EEXIST      Freq are same and volt are different OR
 837  *              Duplicate OPPs (both freq and volt are same) and !opp->available
 838  * -ENOMEM      Memory allocation failure
 839  * -ENODEV      when 'operating-points' property is not found or is invalid data
 840  *              in device node.
 841  * -ENODATA     when empty 'operating-points' property is found
 842  * -EINVAL      when invalid entries are found in opp-v2 table
 843  */
 844 int dev_pm_opp_of_add_table_indexed(struct device *dev, int index)
 845 {
 846         struct opp_table *opp_table;
 847         int ret, count;
 848
 849         if (index) {
 850                 /*
 851                  * If only one phandle is present, then the same OPP table
 852                  * applies for all index requests.
 853                  */
 854                 count = of_count_phandle_with_args(dev->of_node,
 855                                                    "operating-points-v2", NULL);
 856                 if (count == 1)
 857                         index = 0;
 858         }
 859
 860         opp_table = dev_pm_opp_get_opp_table_indexed(dev, index);
 861         if (!opp_table)
 862                 return -ENOMEM;
 863
 864         ret = _of_add_opp_table_v2(dev, opp_table);
 865         if (ret)
 866                 dev_pm_opp_put_opp_table(opp_table);
 867
 868         return ret;
 869 }
 870 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table_indexed);
 871
 872 /* CPU device specific helpers */
 873
 874 /**
 875  * dev_pm_opp_of_cpumask_remove_table() - Removes OPP table for @cpumask
 876  * @cpumask:    cpumask for which OPP table needs to be removed
 877  *
 878  * This removes the OPP tables for CPUs present in the @cpumask.
 879  * This should be used only to remove static entries created from DT.
 880  */
 881 void dev_pm_opp_of_cpumask_remove_table(const struct cpumask *cpumask)
 882 {
 883         _dev_pm_opp_cpumask_remove_table(cpumask, -1);
 884 }
 885 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_remove_table);
 886
 887 /**
 888  * dev_pm_opp_of_cpumask_add_table() - Adds OPP table for @cpumask
 889  * @cpumask:    cpumask for which OPP table needs to be added.
 890  *
 891  * This adds the OPP tables for CPUs present in the @cpumask.
 892  */
 893 int dev_pm_opp_of_cpumask_add_table(const struct cpumask *cpumask)
 894 {
 895         struct device *cpu_dev;
 896         int cpu, ret;
 897
 898         if (WARN_ON(cpumask_empty(cpumask)))
 899                 return -ENODEV;
 900
 901         for_each_cpu(cpu, cpumask) {
 902                 cpu_dev = get_cpu_device(cpu);
 903                 if (!cpu_dev) {
 904                         pr_err("%s: failed to get cpu%d device\n", __func__,
 905                                cpu);
 906                         ret = -ENODEV;
 907                         goto remove_table;
 908                 }
 909
 910                 ret = dev_pm_opp_of_add_table(cpu_dev);
 911                 if (ret) {
 912                         /*
 913                          * OPP may get registered dynamically, don't print error
 914                          * message here.
 915                          */
 916                         pr_debug("%s: couldn't find opp table for cpu:%d, %d\n",
 917                                  __func__, cpu, ret);
 918
 919                         goto remove_table;
 920                 }
 921         }
 922
 923         return 0;
 924
 925 remove_table:
 926         /* Free all other OPPs */
 927         _dev_pm_opp_cpumask_remove_table(cpumask, cpu);
 928
 929         return ret;
 930 }
 931 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_add_table);
 932
 933 /*
 934  * Works only for OPP v2 bindings.
 935  *
 936  * Returns -ENOENT if operating-points-v2 bindings aren't supported.
 937  */
 938 /**
 939  * dev_pm_opp_of_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with
 940  *                                    @cpu_dev using operating-points-v2
 941  *                                    bindings.
 942  *
 943  * @cpu_dev:    CPU device for which we do this operation
 944  * @cpumask:    cpumask to update with information of sharing CPUs
 945  *
 946  * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev.
 947  *
 948  * Returns -ENOENT if operating-points-v2 isn't present for @cpu_dev.
 949  */
 950 int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev,
 951                                    struct cpumask *cpumask)
 952 {
 953         struct device_node *np, *tmp_np, *cpu_np;
 954         int cpu, ret = 0;
 955
 956         /* Get OPP descriptor node */
 957         np = dev_pm_opp_of_get_opp_desc_node(cpu_dev);
 958         if (!np) {
 959                 dev_dbg(cpu_dev, "%s: Couldn't find opp node.\n", __func__);
 960                 return -ENOENT;
 961         }
 962
 963         cpumask_set_cpu(cpu_dev->id, cpumask);
 964
 965         /* OPPs are shared ? */
 966         if (!of_property_read_bool(np, "opp-shared"))
 967                 goto put_cpu_node;
 968
 969         for_each_possible_cpu(cpu) {
 970                 if (cpu == cpu_dev->id)
 971                         continue;
 972
 973                 cpu_np = of_cpu_device_node_get(cpu);
 974                 if (!cpu_np) {
 975                         dev_err(cpu_dev, "%s: failed to get cpu%d node\n",
 976                                 __func__, cpu);
 977                         ret = -ENOENT;
 978                         goto put_cpu_node;
 979                 }
 980
 981                 /* Get OPP descriptor node */
 982                 tmp_np = _opp_of_get_opp_desc_node(cpu_np, 0);
 983                 of_node_put(cpu_np);
 984                 if (!tmp_np) {
 985                         pr_err("%pOF: Couldn't find opp node\n", cpu_np);
 986                         ret = -ENOENT;
 987                         goto put_cpu_node;
 988                 }
 989
 990                 /* CPUs are sharing opp node */
 991                 if (np == tmp_np)
 992                         cpumask_set_cpu(cpu, cpumask);
 993
 994                 of_node_put(tmp_np);
 995         }
 996
 997 put_cpu_node:
 998         of_node_put(np);
 999         return ret;
1000 }
1001 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus);
1002
1003 /**
1004  * of_get_required_opp_performance_state() - Search for required OPP and return its performance state.
1005  * @np: Node that contains the "required-opps" property.
1006  * @index: Index of the phandle to parse.
1007  *
1008  * Returns the performance state of the OPP pointed out by the "required-opps"
1009  * property at @index in @np.
1010  *
1011  * Return: Zero or positive performance state on success, otherwise negative
1012  * value on errors.
1013  */
1014 int of_get_required_opp_performance_state(struct device_node *np, int index)
1015 {
1016         struct dev_pm_opp *opp;
1017         struct device_node *required_np;
1018         struct opp_table *opp_table;
1019         int pstate = -EINVAL;
1020
1021         required_np = of_parse_required_opp(np, index);
1022         if (!required_np)
1023                 return -EINVAL;
1024
1025         opp_table = _find_table_of_opp_np(required_np);
1026         if (IS_ERR(opp_table)) {
1027                 pr_err("%s: Failed to find required OPP table %pOF: %ld\n",
1028                        __func__, np, PTR_ERR(opp_table));
1029                 goto put_required_np;
1030         }
1031
1032         opp = _find_opp_of_np(opp_table, required_np);
1033         if (opp) {
1034                 pstate = opp->pstate;
1035                 dev_pm_opp_put(opp);
1036         }
1037
1038         dev_pm_opp_put_opp_table(opp_table);
1039
1040 put_required_np:
1041         of_node_put(required_np);
1042
1043         return pstate;
1044 }
1045 EXPORT_SYMBOL_GPL(of_get_required_opp_performance_state);
1046
1047 /**
1048  * dev_pm_opp_get_of_node() - Gets the DT node corresponding to an opp
1049  * @opp:        opp for which DT node has to be returned for
1050  *
1051  * Return: DT node corresponding to the opp, else 0 on success.
1052  *
1053  * The caller needs to put the node with of_node_put() after using it.
1054  */
1055 struct device_node *dev_pm_opp_get_of_node(struct dev_pm_opp *opp)
1056 {
1057         if (IS_ERR_OR_NULL(opp)) {
1058                 pr_err("%s: Invalid parameters\n", __func__);
1059                 return NULL;
1060         }
1061
1062         return of_node_get(opp->np);
1063 }
1064 EXPORT_SYMBOL_GPL(dev_pm_opp_get_of_node);
1065
1066 /*
1067  * Callback function provided to the Energy Model framework upon registration.
1068  * This computes the power estimated by @CPU at @kHz if it is the frequency
1069  * of an existing OPP, or at the frequency of the first OPP above @kHz otherwise
1070  * (see dev_pm_opp_find_freq_ceil()). This function updates @kHz to the ceiled
1071  * frequency and @mW to the associated power. The power is estimated as
1072  * P = C * V^2 * f with C being the CPU's capacitance and V and f respectively
1073  * the voltage and frequency of the OPP.
1074  *
1075  * Returns -ENODEV if the CPU device cannot be found, -EINVAL if the power
1076  * calculation failed because of missing parameters, 0 otherwise.
1077  */
1078 static int __maybe_unused _get_cpu_power(unsigned long *mW, unsigned long *kHz,
1079                                          int cpu)
1080 {
1081         struct device *cpu_dev;
1082         struct dev_pm_opp *opp;
1083         struct device_node *np;
1084         unsigned long mV, Hz;
1085         u32 cap;
1086         u64 tmp;
1087         int ret;
1088
1089         cpu_dev = get_cpu_device(cpu);
1090         if (!cpu_dev)
1091                 return -ENODEV;
1092
1093         np = of_node_get(cpu_dev->of_node);
1094         if (!np)
1095                 return -EINVAL;
1096
1097         ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1098         of_node_put(np);
1099         if (ret)
1100                 return -EINVAL;
1101
1102         Hz = *kHz * 1000;
1103         opp = dev_pm_opp_find_freq_ceil(cpu_dev, &Hz);
1104         if (IS_ERR(opp))
1105                 return -EINVAL;
1106
1107         mV = dev_pm_opp_get_voltage(opp) / 1000;
1108         dev_pm_opp_put(opp);
1109         if (!mV)
1110                 return -EINVAL;
1111
1112         tmp = (u64)cap * mV * mV * (Hz / 1000000);
1113         do_div(tmp, 1000000000);
1114
1115         *mW = (unsigned long)tmp;
1116         *kHz = Hz / 1000;
1117
1118         return 0;
1119 }
1120
1121 /**
1122  * dev_pm_opp_of_register_em() - Attempt to register an Energy Model
1123  * @cpus        : CPUs for which an Energy Model has to be registered
1124  *
1125  * This checks whether the "dynamic-power-coefficient" devicetree property has
1126  * been specified, and tries to register an Energy Model with it if it has.
1127  */
1128 void dev_pm_opp_of_register_em(struct cpumask *cpus)
1129 {
1130         struct em_data_callback em_cb = EM_DATA_CB(_get_cpu_power);
1131         int ret, nr_opp, cpu = cpumask_first(cpus);
1132         struct device *cpu_dev;
1133         struct device_node *np;
1134         u32 cap;
1135
1136         cpu_dev = get_cpu_device(cpu);
1137         if (!cpu_dev)
1138                 return;
1139
1140         nr_opp = dev_pm_opp_get_opp_count(cpu_dev);
1141         if (nr_opp <= 0)
1142                 return;
1143
1144         np = of_node_get(cpu_dev->of_node);
1145         if (!np)
1146                 return;
1147
1148         /*
1149          * Register an EM only if the 'dynamic-power-coefficient' property is
1150          * set in devicetree. It is assumed the voltage values are known if that
1151          * property is set since it is useless otherwise. If voltages are not
1152          * known, just let the EM registration fail with an error to alert the
1153          * user about the inconsistent configuration.
1154          */
1155         ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1156         of_node_put(np);
1157         if (ret || !cap)
1158                 return;
1159
1160         em_register_perf_domain(cpus, nr_opp, &em_cb);
1161 }
1162 EXPORT_SYMBOL_GPL(dev_pm_opp_of_register_em);