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/slab.h> 21 #include <linux/export.h> 22 23 #include "opp.h" 24 25 static struct opp_table *_managed_opp(const struct device_node *np) 26 { 27 struct opp_table *opp_table, *managed_table = NULL; 28 29 mutex_lock(&opp_table_lock); 30 31 list_for_each_entry(opp_table, &opp_tables, node) { 32 if (opp_table->np == np) { 33 /* 34 * Multiple devices can point to the same OPP table and 35 * so will have same node-pointer, np. 36 * 37 * But the OPPs will be considered as shared only if the 38 * OPP table contains a "opp-shared" property. 39 */ 40 if (opp_table->shared_opp == OPP_TABLE_ACCESS_SHARED) { 41 _get_opp_table_kref(opp_table); 42 managed_table = opp_table; 43 } 44 45 break; 46 } 47 } 48 49 mutex_unlock(&opp_table_lock); 50 51 return managed_table; 52 } 53 54 void _of_init_opp_table(struct opp_table *opp_table, struct device *dev) 55 { 56 struct device_node *np; 57 58 /* 59 * Only required for backward compatibility with v1 bindings, but isn't 60 * harmful for other cases. And so we do it unconditionally. 61 */ 62 np = of_node_get(dev->of_node); 63 if (np) { 64 u32 val; 65 66 if (!of_property_read_u32(np, "clock-latency", &val)) 67 opp_table->clock_latency_ns_max = val; 68 of_property_read_u32(np, "voltage-tolerance", 69 &opp_table->voltage_tolerance_v1); 70 of_node_put(np); 71 } 72 } 73 74 static bool _opp_is_supported(struct device *dev, struct opp_table *opp_table, 75 struct device_node *np) 76 { 77 unsigned int count = opp_table->supported_hw_count; 78 u32 version; 79 int ret; 80 81 if (!opp_table->supported_hw) { 82 /* 83 * In the case that no supported_hw has been set by the 84 * platform but there is an opp-supported-hw value set for 85 * an OPP then the OPP should not be enabled as there is 86 * no way to see if the hardware supports it. 87 */ 88 if (of_find_property(np, "opp-supported-hw", NULL)) 89 return false; 90 else 91 return true; 92 } 93 94 while (count--) { 95 ret = of_property_read_u32_index(np, "opp-supported-hw", count, 96 &version); 97 if (ret) { 98 dev_warn(dev, "%s: failed to read opp-supported-hw property at index %d: %d\n", 99 __func__, count, ret); 100 return false; 101 } 102 103 /* Both of these are bitwise masks of the versions */ 104 if (!(version & opp_table->supported_hw[count])) 105 return false; 106 } 107 108 return true; 109 } 110 111 static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev, 112 struct opp_table *opp_table) 113 { 114 u32 *microvolt, *microamp = NULL; 115 int supplies, vcount, icount, ret, i, j; 116 struct property *prop = NULL; 117 char name[NAME_MAX]; 118 119 supplies = opp_table->regulator_count ? opp_table->regulator_count : 1; 120 121 /* Search for "opp-microvolt-<name>" */ 122 if (opp_table->prop_name) { 123 snprintf(name, sizeof(name), "opp-microvolt-%s", 124 opp_table->prop_name); 125 prop = of_find_property(opp->np, name, NULL); 126 } 127 128 if (!prop) { 129 /* Search for "opp-microvolt" */ 130 sprintf(name, "opp-microvolt"); 131 prop = of_find_property(opp->np, name, NULL); 132 133 /* Missing property isn't a problem, but an invalid entry is */ 134 if (!prop) { 135 if (!opp_table->regulator_count) 136 return 0; 137 138 dev_err(dev, "%s: opp-microvolt missing although OPP managing regulators\n", 139 __func__); 140 return -EINVAL; 141 } 142 } 143 144 vcount = of_property_count_u32_elems(opp->np, name); 145 if (vcount < 0) { 146 dev_err(dev, "%s: Invalid %s property (%d)\n", 147 __func__, name, vcount); 148 return vcount; 149 } 150 151 /* There can be one or three elements per supply */ 152 if (vcount != supplies && vcount != supplies * 3) { 153 dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n", 154 __func__, name, vcount, supplies); 155 return -EINVAL; 156 } 157 158 microvolt = kmalloc_array(vcount, sizeof(*microvolt), GFP_KERNEL); 159 if (!microvolt) 160 return -ENOMEM; 161 162 ret = of_property_read_u32_array(opp->np, name, microvolt, vcount); 163 if (ret) { 164 dev_err(dev, "%s: error parsing %s: %d\n", __func__, name, ret); 165 ret = -EINVAL; 166 goto free_microvolt; 167 } 168 169 /* Search for "opp-microamp-<name>" */ 170 prop = NULL; 171 if (opp_table->prop_name) { 172 snprintf(name, sizeof(name), "opp-microamp-%s", 173 opp_table->prop_name); 174 prop = of_find_property(opp->np, name, NULL); 175 } 176 177 if (!prop) { 178 /* Search for "opp-microamp" */ 179 sprintf(name, "opp-microamp"); 180 prop = of_find_property(opp->np, name, NULL); 181 } 182 183 if (prop) { 184 icount = of_property_count_u32_elems(opp->np, name); 185 if (icount < 0) { 186 dev_err(dev, "%s: Invalid %s property (%d)\n", __func__, 187 name, icount); 188 ret = icount; 189 goto free_microvolt; 190 } 191 192 if (icount != supplies) { 193 dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n", 194 __func__, name, icount, supplies); 195 ret = -EINVAL; 196 goto free_microvolt; 197 } 198 199 microamp = kmalloc_array(icount, sizeof(*microamp), GFP_KERNEL); 200 if (!microamp) { 201 ret = -EINVAL; 202 goto free_microvolt; 203 } 204 205 ret = of_property_read_u32_array(opp->np, name, microamp, 206 icount); 207 if (ret) { 208 dev_err(dev, "%s: error parsing %s: %d\n", __func__, 209 name, ret); 210 ret = -EINVAL; 211 goto free_microamp; 212 } 213 } 214 215 for (i = 0, j = 0; i < supplies; i++) { 216 opp->supplies[i].u_volt = microvolt[j++]; 217 218 if (vcount == supplies) { 219 opp->supplies[i].u_volt_min = opp->supplies[i].u_volt; 220 opp->supplies[i].u_volt_max = opp->supplies[i].u_volt; 221 } else { 222 opp->supplies[i].u_volt_min = microvolt[j++]; 223 opp->supplies[i].u_volt_max = microvolt[j++]; 224 } 225 226 if (microamp) 227 opp->supplies[i].u_amp = microamp[i]; 228 } 229 230 free_microamp: 231 kfree(microamp); 232 free_microvolt: 233 kfree(microvolt); 234 235 return ret; 236 } 237 238 /** 239 * dev_pm_opp_of_remove_table() - Free OPP table entries created from static DT 240 * entries 241 * @dev: device pointer used to lookup OPP table. 242 * 243 * Free OPPs created using static entries present in DT. 244 */ 245 void dev_pm_opp_of_remove_table(struct device *dev) 246 { 247 _dev_pm_opp_find_and_remove_table(dev, false); 248 } 249 EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table); 250 251 /* Returns opp descriptor node for a device node, caller must 252 * do of_node_put() */ 253 static struct device_node *_opp_of_get_opp_desc_node(struct device_node *np) 254 { 255 /* 256 * There should be only ONE phandle present in "operating-points-v2" 257 * property. 258 */ 259 260 return of_parse_phandle(np, "operating-points-v2", 0); 261 } 262 263 /* Returns opp descriptor node for a device, caller must do of_node_put() */ 264 struct device_node *dev_pm_opp_of_get_opp_desc_node(struct device *dev) 265 { 266 return _opp_of_get_opp_desc_node(dev->of_node); 267 } 268 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_opp_desc_node); 269 270 /** 271 * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings) 272 * @opp_table: OPP table 273 * @dev: device for which we do this operation 274 * @np: device node 275 * 276 * This function adds an opp definition to the opp table and returns status. The 277 * opp can be controlled using dev_pm_opp_enable/disable functions and may be 278 * removed by dev_pm_opp_remove. 279 * 280 * Return: 281 * 0 On success OR 282 * Duplicate OPPs (both freq and volt are same) and opp->available 283 * -EEXIST Freq are same and volt are different OR 284 * Duplicate OPPs (both freq and volt are same) and !opp->available 285 * -ENOMEM Memory allocation failure 286 * -EINVAL Failed parsing the OPP node 287 */ 288 static int _opp_add_static_v2(struct opp_table *opp_table, struct device *dev, 289 struct device_node *np) 290 { 291 struct dev_pm_opp *new_opp; 292 u64 rate; 293 u32 val; 294 int ret; 295 296 new_opp = _opp_allocate(opp_table); 297 if (!new_opp) 298 return -ENOMEM; 299 300 ret = of_property_read_u64(np, "opp-hz", &rate); 301 if (ret < 0) { 302 dev_err(dev, "%s: opp-hz not found\n", __func__); 303 goto free_opp; 304 } 305 306 /* Check if the OPP supports hardware's hierarchy of versions or not */ 307 if (!_opp_is_supported(dev, opp_table, np)) { 308 dev_dbg(dev, "OPP not supported by hardware: %llu\n", rate); 309 goto free_opp; 310 } 311 312 /* 313 * Rate is defined as an unsigned long in clk API, and so casting 314 * explicitly to its type. Must be fixed once rate is 64 bit 315 * guaranteed in clk API. 316 */ 317 new_opp->rate = (unsigned long)rate; 318 new_opp->turbo = of_property_read_bool(np, "turbo-mode"); 319 320 new_opp->np = np; 321 new_opp->dynamic = false; 322 new_opp->available = true; 323 324 if (!of_property_read_u32(np, "clock-latency-ns", &val)) 325 new_opp->clock_latency_ns = val; 326 327 ret = opp_parse_supplies(new_opp, dev, opp_table); 328 if (ret) 329 goto free_opp; 330 331 ret = _opp_add(dev, new_opp, opp_table); 332 if (ret) { 333 /* Don't return error for duplicate OPPs */ 334 if (ret == -EBUSY) 335 ret = 0; 336 goto free_opp; 337 } 338 339 /* OPP to select on device suspend */ 340 if (of_property_read_bool(np, "opp-suspend")) { 341 if (opp_table->suspend_opp) { 342 dev_warn(dev, "%s: Multiple suspend OPPs found (%lu %lu)\n", 343 __func__, opp_table->suspend_opp->rate, 344 new_opp->rate); 345 } else { 346 new_opp->suspend = true; 347 opp_table->suspend_opp = new_opp; 348 } 349 } 350 351 if (new_opp->clock_latency_ns > opp_table->clock_latency_ns_max) 352 opp_table->clock_latency_ns_max = new_opp->clock_latency_ns; 353 354 pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu\n", 355 __func__, new_opp->turbo, new_opp->rate, 356 new_opp->supplies[0].u_volt, new_opp->supplies[0].u_volt_min, 357 new_opp->supplies[0].u_volt_max, new_opp->clock_latency_ns); 358 359 /* 360 * Notify the changes in the availability of the operable 361 * frequency/voltage list. 362 */ 363 blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ADD, new_opp); 364 return 0; 365 366 free_opp: 367 _opp_free(new_opp); 368 369 return ret; 370 } 371 372 /* Initializes OPP tables based on new bindings */ 373 static int _of_add_opp_table_v2(struct device *dev, struct device_node *opp_np) 374 { 375 struct device_node *np; 376 struct opp_table *opp_table; 377 int ret = 0, count = 0; 378 379 opp_table = _managed_opp(opp_np); 380 if (opp_table) { 381 /* OPPs are already managed */ 382 if (!_add_opp_dev(dev, opp_table)) 383 ret = -ENOMEM; 384 goto put_opp_table; 385 } 386 387 opp_table = dev_pm_opp_get_opp_table(dev); 388 if (!opp_table) 389 return -ENOMEM; 390 391 /* We have opp-table node now, iterate over it and add OPPs */ 392 for_each_available_child_of_node(opp_np, np) { 393 count++; 394 395 ret = _opp_add_static_v2(opp_table, dev, np); 396 if (ret) { 397 dev_err(dev, "%s: Failed to add OPP, %d\n", __func__, 398 ret); 399 _dev_pm_opp_remove_table(opp_table, dev, false); 400 of_node_put(np); 401 goto put_opp_table; 402 } 403 } 404 405 /* There should be one of more OPP defined */ 406 if (WARN_ON(!count)) { 407 ret = -ENOENT; 408 goto put_opp_table; 409 } 410 411 opp_table->np = opp_np; 412 if (of_property_read_bool(opp_np, "opp-shared")) 413 opp_table->shared_opp = OPP_TABLE_ACCESS_SHARED; 414 else 415 opp_table->shared_opp = OPP_TABLE_ACCESS_EXCLUSIVE; 416 417 put_opp_table: 418 dev_pm_opp_put_opp_table(opp_table); 419 420 return ret; 421 } 422 423 /* Initializes OPP tables based on old-deprecated bindings */ 424 static int _of_add_opp_table_v1(struct device *dev) 425 { 426 struct opp_table *opp_table; 427 const struct property *prop; 428 const __be32 *val; 429 int nr, ret = 0; 430 431 prop = of_find_property(dev->of_node, "operating-points", NULL); 432 if (!prop) 433 return -ENODEV; 434 if (!prop->value) 435 return -ENODATA; 436 437 /* 438 * Each OPP is a set of tuples consisting of frequency and 439 * voltage like <freq-kHz vol-uV>. 440 */ 441 nr = prop->length / sizeof(u32); 442 if (nr % 2) { 443 dev_err(dev, "%s: Invalid OPP table\n", __func__); 444 return -EINVAL; 445 } 446 447 opp_table = dev_pm_opp_get_opp_table(dev); 448 if (!opp_table) 449 return -ENOMEM; 450 451 val = prop->value; 452 while (nr) { 453 unsigned long freq = be32_to_cpup(val++) * 1000; 454 unsigned long volt = be32_to_cpup(val++); 455 456 ret = _opp_add_v1(opp_table, dev, freq, volt, false); 457 if (ret) { 458 dev_err(dev, "%s: Failed to add OPP %ld (%d)\n", 459 __func__, freq, ret); 460 _dev_pm_opp_remove_table(opp_table, dev, false); 461 break; 462 } 463 nr -= 2; 464 } 465 466 dev_pm_opp_put_opp_table(opp_table); 467 return ret; 468 } 469 470 /** 471 * dev_pm_opp_of_add_table() - Initialize opp table from device tree 472 * @dev: device pointer used to lookup OPP table. 473 * 474 * Register the initial OPP table with the OPP library for given device. 475 * 476 * Return: 477 * 0 On success OR 478 * Duplicate OPPs (both freq and volt are same) and opp->available 479 * -EEXIST Freq are same and volt are different OR 480 * Duplicate OPPs (both freq and volt are same) and !opp->available 481 * -ENOMEM Memory allocation failure 482 * -ENODEV when 'operating-points' property is not found or is invalid data 483 * in device node. 484 * -ENODATA when empty 'operating-points' property is found 485 * -EINVAL when invalid entries are found in opp-v2 table 486 */ 487 int dev_pm_opp_of_add_table(struct device *dev) 488 { 489 struct device_node *opp_np; 490 int ret; 491 492 /* 493 * OPPs have two version of bindings now. The older one is deprecated, 494 * try for the new binding first. 495 */ 496 opp_np = dev_pm_opp_of_get_opp_desc_node(dev); 497 if (!opp_np) { 498 /* 499 * Try old-deprecated bindings for backward compatibility with 500 * older dtbs. 501 */ 502 return _of_add_opp_table_v1(dev); 503 } 504 505 ret = _of_add_opp_table_v2(dev, opp_np); 506 of_node_put(opp_np); 507 508 return ret; 509 } 510 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table); 511 512 /* CPU device specific helpers */ 513 514 /** 515 * dev_pm_opp_of_cpumask_remove_table() - Removes OPP table for @cpumask 516 * @cpumask: cpumask for which OPP table needs to be removed 517 * 518 * This removes the OPP tables for CPUs present in the @cpumask. 519 * This should be used only to remove static entries created from DT. 520 */ 521 void dev_pm_opp_of_cpumask_remove_table(const struct cpumask *cpumask) 522 { 523 _dev_pm_opp_cpumask_remove_table(cpumask, true); 524 } 525 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_remove_table); 526 527 /** 528 * dev_pm_opp_of_cpumask_add_table() - Adds OPP table for @cpumask 529 * @cpumask: cpumask for which OPP table needs to be added. 530 * 531 * This adds the OPP tables for CPUs present in the @cpumask. 532 */ 533 int dev_pm_opp_of_cpumask_add_table(const struct cpumask *cpumask) 534 { 535 struct device *cpu_dev; 536 int cpu, ret = 0; 537 538 WARN_ON(cpumask_empty(cpumask)); 539 540 for_each_cpu(cpu, cpumask) { 541 cpu_dev = get_cpu_device(cpu); 542 if (!cpu_dev) { 543 pr_err("%s: failed to get cpu%d device\n", __func__, 544 cpu); 545 continue; 546 } 547 548 ret = dev_pm_opp_of_add_table(cpu_dev); 549 if (ret) { 550 /* 551 * OPP may get registered dynamically, don't print error 552 * message here. 553 */ 554 pr_debug("%s: couldn't find opp table for cpu:%d, %d\n", 555 __func__, cpu, ret); 556 557 /* Free all other OPPs */ 558 dev_pm_opp_of_cpumask_remove_table(cpumask); 559 break; 560 } 561 } 562 563 return ret; 564 } 565 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_add_table); 566 567 /* 568 * Works only for OPP v2 bindings. 569 * 570 * Returns -ENOENT if operating-points-v2 bindings aren't supported. 571 */ 572 /** 573 * dev_pm_opp_of_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with 574 * @cpu_dev using operating-points-v2 575 * bindings. 576 * 577 * @cpu_dev: CPU device for which we do this operation 578 * @cpumask: cpumask to update with information of sharing CPUs 579 * 580 * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev. 581 * 582 * Returns -ENOENT if operating-points-v2 isn't present for @cpu_dev. 583 */ 584 int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev, 585 struct cpumask *cpumask) 586 { 587 struct device_node *np, *tmp_np, *cpu_np; 588 int cpu, ret = 0; 589 590 /* Get OPP descriptor node */ 591 np = dev_pm_opp_of_get_opp_desc_node(cpu_dev); 592 if (!np) { 593 dev_dbg(cpu_dev, "%s: Couldn't find opp node.\n", __func__); 594 return -ENOENT; 595 } 596 597 cpumask_set_cpu(cpu_dev->id, cpumask); 598 599 /* OPPs are shared ? */ 600 if (!of_property_read_bool(np, "opp-shared")) 601 goto put_cpu_node; 602 603 for_each_possible_cpu(cpu) { 604 if (cpu == cpu_dev->id) 605 continue; 606 607 cpu_np = of_cpu_device_node_get(cpu); 608 if (!cpu_np) { 609 dev_err(cpu_dev, "%s: failed to get cpu%d node\n", 610 __func__, cpu); 611 ret = -ENOENT; 612 goto put_cpu_node; 613 } 614 615 /* Get OPP descriptor node */ 616 tmp_np = _opp_of_get_opp_desc_node(cpu_np); 617 of_node_put(cpu_np); 618 if (!tmp_np) { 619 pr_err("%pOF: Couldn't find opp node\n", cpu_np); 620 ret = -ENOENT; 621 goto put_cpu_node; 622 } 623 624 /* CPUs are sharing opp node */ 625 if (np == tmp_np) 626 cpumask_set_cpu(cpu, cpumask); 627 628 of_node_put(tmp_np); 629 } 630 631 put_cpu_node: 632 of_node_put(np); 633 return ret; 634 } 635 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus); 636