1 /* 2 * processor_perflib.c - ACPI Processor P-States Library ($Revision: 71 $) 3 * 4 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com> 5 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> 6 * Copyright (C) 2004 Dominik Brodowski <linux@brodo.de> 7 * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> 8 * - Added processor hotplug support 9 * 10 * 11 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 12 * 13 * This program is free software; you can redistribute it and/or modify 14 * it under the terms of the GNU General Public License as published by 15 * the Free Software Foundation; either version 2 of the License, or (at 16 * your option) any later version. 17 * 18 * This program is distributed in the hope that it will be useful, but 19 * WITHOUT ANY WARRANTY; without even the implied warranty of 20 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 21 * General Public License for more details. 22 * 23 * You should have received a copy of the GNU General Public License along 24 * with this program; if not, write to the Free Software Foundation, Inc., 25 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. 26 * 27 */ 28 29 #include <linux/kernel.h> 30 #include <linux/module.h> 31 #include <linux/init.h> 32 #include <linux/cpufreq.h> 33 #include <linux/slab.h> 34 35 #ifdef CONFIG_X86 36 #include <asm/cpufeature.h> 37 #endif 38 39 #include <acpi/acpi_bus.h> 40 #include <acpi/acpi_drivers.h> 41 #include <acpi/processor.h> 42 43 #define PREFIX "ACPI: " 44 45 #define ACPI_PROCESSOR_CLASS "processor" 46 #define ACPI_PROCESSOR_FILE_PERFORMANCE "performance" 47 #define _COMPONENT ACPI_PROCESSOR_COMPONENT 48 ACPI_MODULE_NAME("processor_perflib"); 49 50 static DEFINE_MUTEX(performance_mutex); 51 52 /* 53 * _PPC support is implemented as a CPUfreq policy notifier: 54 * This means each time a CPUfreq driver registered also with 55 * the ACPI core is asked to change the speed policy, the maximum 56 * value is adjusted so that it is within the platform limit. 57 * 58 * Also, when a new platform limit value is detected, the CPUfreq 59 * policy is adjusted accordingly. 60 */ 61 62 /* ignore_ppc: 63 * -1 -> cpufreq low level drivers not initialized -> _PSS, etc. not called yet 64 * ignore _PPC 65 * 0 -> cpufreq low level drivers initialized -> consider _PPC values 66 * 1 -> ignore _PPC totally -> forced by user through boot param 67 */ 68 static int ignore_ppc = -1; 69 module_param(ignore_ppc, int, 0644); 70 MODULE_PARM_DESC(ignore_ppc, "If the frequency of your machine gets wrongly" \ 71 "limited by BIOS, this should help"); 72 73 #define PPC_REGISTERED 1 74 #define PPC_IN_USE 2 75 76 static int acpi_processor_ppc_status; 77 78 static int acpi_processor_ppc_notifier(struct notifier_block *nb, 79 unsigned long event, void *data) 80 { 81 struct cpufreq_policy *policy = data; 82 struct acpi_processor *pr; 83 unsigned int ppc = 0; 84 85 if (event == CPUFREQ_START && ignore_ppc <= 0) { 86 ignore_ppc = 0; 87 return 0; 88 } 89 90 if (ignore_ppc) 91 return 0; 92 93 if (event != CPUFREQ_INCOMPATIBLE) 94 return 0; 95 96 mutex_lock(&performance_mutex); 97 98 pr = per_cpu(processors, policy->cpu); 99 if (!pr || !pr->performance) 100 goto out; 101 102 ppc = (unsigned int)pr->performance_platform_limit; 103 104 if (ppc >= pr->performance->state_count) 105 goto out; 106 107 cpufreq_verify_within_limits(policy, 0, 108 pr->performance->states[ppc]. 109 core_frequency * 1000); 110 111 out: 112 mutex_unlock(&performance_mutex); 113 114 return 0; 115 } 116 117 static struct notifier_block acpi_ppc_notifier_block = { 118 .notifier_call = acpi_processor_ppc_notifier, 119 }; 120 121 static int acpi_processor_get_platform_limit(struct acpi_processor *pr) 122 { 123 acpi_status status = 0; 124 unsigned long long ppc = 0; 125 126 127 if (!pr) 128 return -EINVAL; 129 130 /* 131 * _PPC indicates the maximum state currently supported by the platform 132 * (e.g. 0 = states 0..n; 1 = states 1..n; etc. 133 */ 134 status = acpi_evaluate_integer(pr->handle, "_PPC", NULL, &ppc); 135 136 if (status != AE_NOT_FOUND) 137 acpi_processor_ppc_status |= PPC_IN_USE; 138 139 if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) { 140 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PPC")); 141 return -ENODEV; 142 } 143 144 pr_debug("CPU %d: _PPC is %d - frequency %s limited\n", pr->id, 145 (int)ppc, ppc ? "" : "not"); 146 147 pr->performance_platform_limit = (int)ppc; 148 149 return 0; 150 } 151 152 #define ACPI_PROCESSOR_NOTIFY_PERFORMANCE 0x80 153 /* 154 * acpi_processor_ppc_ost: Notify firmware the _PPC evaluation status 155 * @handle: ACPI processor handle 156 * @status: the status code of _PPC evaluation 157 * 0: success. OSPM is now using the performance state specificed. 158 * 1: failure. OSPM has not changed the number of P-states in use 159 */ 160 static void acpi_processor_ppc_ost(acpi_handle handle, int status) 161 { 162 union acpi_object params[2] = { 163 {.type = ACPI_TYPE_INTEGER,}, 164 {.type = ACPI_TYPE_INTEGER,}, 165 }; 166 struct acpi_object_list arg_list = {2, params}; 167 acpi_handle temp; 168 169 params[0].integer.value = ACPI_PROCESSOR_NOTIFY_PERFORMANCE; 170 params[1].integer.value = status; 171 172 /* when there is no _OST , skip it */ 173 if (ACPI_FAILURE(acpi_get_handle(handle, "_OST", &temp))) 174 return; 175 176 acpi_evaluate_object(handle, "_OST", &arg_list, NULL); 177 return; 178 } 179 180 int acpi_processor_ppc_has_changed(struct acpi_processor *pr, int event_flag) 181 { 182 int ret; 183 184 if (ignore_ppc) { 185 /* 186 * Only when it is notification event, the _OST object 187 * will be evaluated. Otherwise it is skipped. 188 */ 189 if (event_flag) 190 acpi_processor_ppc_ost(pr->handle, 1); 191 return 0; 192 } 193 194 ret = acpi_processor_get_platform_limit(pr); 195 /* 196 * Only when it is notification event, the _OST object 197 * will be evaluated. Otherwise it is skipped. 198 */ 199 if (event_flag) { 200 if (ret < 0) 201 acpi_processor_ppc_ost(pr->handle, 1); 202 else 203 acpi_processor_ppc_ost(pr->handle, 0); 204 } 205 if (ret < 0) 206 return (ret); 207 else 208 return cpufreq_update_policy(pr->id); 209 } 210 211 int acpi_processor_get_bios_limit(int cpu, unsigned int *limit) 212 { 213 struct acpi_processor *pr; 214 215 pr = per_cpu(processors, cpu); 216 if (!pr || !pr->performance || !pr->performance->state_count) 217 return -ENODEV; 218 *limit = pr->performance->states[pr->performance_platform_limit]. 219 core_frequency * 1000; 220 return 0; 221 } 222 EXPORT_SYMBOL(acpi_processor_get_bios_limit); 223 224 void acpi_processor_ppc_init(void) 225 { 226 if (!cpufreq_register_notifier 227 (&acpi_ppc_notifier_block, CPUFREQ_POLICY_NOTIFIER)) 228 acpi_processor_ppc_status |= PPC_REGISTERED; 229 else 230 printk(KERN_DEBUG 231 "Warning: Processor Platform Limit not supported.\n"); 232 } 233 234 void acpi_processor_ppc_exit(void) 235 { 236 if (acpi_processor_ppc_status & PPC_REGISTERED) 237 cpufreq_unregister_notifier(&acpi_ppc_notifier_block, 238 CPUFREQ_POLICY_NOTIFIER); 239 240 acpi_processor_ppc_status &= ~PPC_REGISTERED; 241 } 242 243 static int acpi_processor_get_performance_control(struct acpi_processor *pr) 244 { 245 int result = 0; 246 acpi_status status = 0; 247 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 248 union acpi_object *pct = NULL; 249 union acpi_object obj = { 0 }; 250 251 252 status = acpi_evaluate_object(pr->handle, "_PCT", NULL, &buffer); 253 if (ACPI_FAILURE(status)) { 254 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PCT")); 255 return -ENODEV; 256 } 257 258 pct = (union acpi_object *)buffer.pointer; 259 if (!pct || (pct->type != ACPI_TYPE_PACKAGE) 260 || (pct->package.count != 2)) { 261 printk(KERN_ERR PREFIX "Invalid _PCT data\n"); 262 result = -EFAULT; 263 goto end; 264 } 265 266 /* 267 * control_register 268 */ 269 270 obj = pct->package.elements[0]; 271 272 if ((obj.type != ACPI_TYPE_BUFFER) 273 || (obj.buffer.length < sizeof(struct acpi_pct_register)) 274 || (obj.buffer.pointer == NULL)) { 275 printk(KERN_ERR PREFIX "Invalid _PCT data (control_register)\n"); 276 result = -EFAULT; 277 goto end; 278 } 279 memcpy(&pr->performance->control_register, obj.buffer.pointer, 280 sizeof(struct acpi_pct_register)); 281 282 /* 283 * status_register 284 */ 285 286 obj = pct->package.elements[1]; 287 288 if ((obj.type != ACPI_TYPE_BUFFER) 289 || (obj.buffer.length < sizeof(struct acpi_pct_register)) 290 || (obj.buffer.pointer == NULL)) { 291 printk(KERN_ERR PREFIX "Invalid _PCT data (status_register)\n"); 292 result = -EFAULT; 293 goto end; 294 } 295 296 memcpy(&pr->performance->status_register, obj.buffer.pointer, 297 sizeof(struct acpi_pct_register)); 298 299 end: 300 kfree(buffer.pointer); 301 302 return result; 303 } 304 305 static int acpi_processor_get_performance_states(struct acpi_processor *pr) 306 { 307 int result = 0; 308 acpi_status status = AE_OK; 309 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; 310 struct acpi_buffer format = { sizeof("NNNNNN"), "NNNNNN" }; 311 struct acpi_buffer state = { 0, NULL }; 312 union acpi_object *pss = NULL; 313 int i; 314 315 316 status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer); 317 if (ACPI_FAILURE(status)) { 318 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PSS")); 319 return -ENODEV; 320 } 321 322 pss = buffer.pointer; 323 if (!pss || (pss->type != ACPI_TYPE_PACKAGE)) { 324 printk(KERN_ERR PREFIX "Invalid _PSS data\n"); 325 result = -EFAULT; 326 goto end; 327 } 328 329 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d performance states\n", 330 pss->package.count)); 331 332 pr->performance->state_count = pss->package.count; 333 pr->performance->states = 334 kmalloc(sizeof(struct acpi_processor_px) * pss->package.count, 335 GFP_KERNEL); 336 if (!pr->performance->states) { 337 result = -ENOMEM; 338 goto end; 339 } 340 341 for (i = 0; i < pr->performance->state_count; i++) { 342 343 struct acpi_processor_px *px = &(pr->performance->states[i]); 344 345 state.length = sizeof(struct acpi_processor_px); 346 state.pointer = px; 347 348 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i)); 349 350 status = acpi_extract_package(&(pss->package.elements[i]), 351 &format, &state); 352 if (ACPI_FAILURE(status)) { 353 ACPI_EXCEPTION((AE_INFO, status, "Invalid _PSS data")); 354 result = -EFAULT; 355 kfree(pr->performance->states); 356 goto end; 357 } 358 359 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 360 "State [%d]: core_frequency[%d] power[%d] transition_latency[%d] bus_master_latency[%d] control[0x%x] status[0x%x]\n", 361 i, 362 (u32) px->core_frequency, 363 (u32) px->power, 364 (u32) px->transition_latency, 365 (u32) px->bus_master_latency, 366 (u32) px->control, (u32) px->status)); 367 368 /* 369 * Check that ACPI's u64 MHz will be valid as u32 KHz in cpufreq 370 */ 371 if (!px->core_frequency || 372 ((u32)(px->core_frequency * 1000) != 373 (px->core_frequency * 1000))) { 374 printk(KERN_ERR FW_BUG PREFIX 375 "Invalid BIOS _PSS frequency: 0x%llx MHz\n", 376 px->core_frequency); 377 result = -EFAULT; 378 kfree(pr->performance->states); 379 goto end; 380 } 381 } 382 383 end: 384 kfree(buffer.pointer); 385 386 return result; 387 } 388 389 static int acpi_processor_get_performance_info(struct acpi_processor *pr) 390 { 391 int result = 0; 392 acpi_status status = AE_OK; 393 acpi_handle handle = NULL; 394 395 if (!pr || !pr->performance || !pr->handle) 396 return -EINVAL; 397 398 status = acpi_get_handle(pr->handle, "_PCT", &handle); 399 if (ACPI_FAILURE(status)) { 400 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 401 "ACPI-based processor performance control unavailable\n")); 402 return -ENODEV; 403 } 404 405 result = acpi_processor_get_performance_control(pr); 406 if (result) 407 goto update_bios; 408 409 result = acpi_processor_get_performance_states(pr); 410 if (result) 411 goto update_bios; 412 413 /* We need to call _PPC once when cpufreq starts */ 414 if (ignore_ppc != 1) 415 result = acpi_processor_get_platform_limit(pr); 416 417 return result; 418 419 /* 420 * Having _PPC but missing frequencies (_PSS, _PCT) is a very good hint that 421 * the BIOS is older than the CPU and does not know its frequencies 422 */ 423 update_bios: 424 #ifdef CONFIG_X86 425 if (ACPI_SUCCESS(acpi_get_handle(pr->handle, "_PPC", &handle))){ 426 if(boot_cpu_has(X86_FEATURE_EST)) 427 printk(KERN_WARNING FW_BUG "BIOS needs update for CPU " 428 "frequency support\n"); 429 } 430 #endif 431 return result; 432 } 433 434 int acpi_processor_notify_smm(struct module *calling_module) 435 { 436 acpi_status status; 437 static int is_done = 0; 438 439 440 if (!(acpi_processor_ppc_status & PPC_REGISTERED)) 441 return -EBUSY; 442 443 if (!try_module_get(calling_module)) 444 return -EINVAL; 445 446 /* is_done is set to negative if an error occurred, 447 * and to postitive if _no_ error occurred, but SMM 448 * was already notified. This avoids double notification 449 * which might lead to unexpected results... 450 */ 451 if (is_done > 0) { 452 module_put(calling_module); 453 return 0; 454 } else if (is_done < 0) { 455 module_put(calling_module); 456 return is_done; 457 } 458 459 is_done = -EIO; 460 461 /* Can't write pstate_control to smi_command if either value is zero */ 462 if ((!acpi_gbl_FADT.smi_command) || (!acpi_gbl_FADT.pstate_control)) { 463 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No SMI port or pstate_control\n")); 464 module_put(calling_module); 465 return 0; 466 } 467 468 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 469 "Writing pstate_control [0x%x] to smi_command [0x%x]\n", 470 acpi_gbl_FADT.pstate_control, acpi_gbl_FADT.smi_command)); 471 472 status = acpi_os_write_port(acpi_gbl_FADT.smi_command, 473 (u32) acpi_gbl_FADT.pstate_control, 8); 474 if (ACPI_FAILURE(status)) { 475 ACPI_EXCEPTION((AE_INFO, status, 476 "Failed to write pstate_control [0x%x] to " 477 "smi_command [0x%x]", acpi_gbl_FADT.pstate_control, 478 acpi_gbl_FADT.smi_command)); 479 module_put(calling_module); 480 return status; 481 } 482 483 /* Success. If there's no _PPC, we need to fear nothing, so 484 * we can allow the cpufreq driver to be rmmod'ed. */ 485 is_done = 1; 486 487 if (!(acpi_processor_ppc_status & PPC_IN_USE)) 488 module_put(calling_module); 489 490 return 0; 491 } 492 493 EXPORT_SYMBOL(acpi_processor_notify_smm); 494 495 static int acpi_processor_get_psd(struct acpi_processor *pr) 496 { 497 int result = 0; 498 acpi_status status = AE_OK; 499 struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL}; 500 struct acpi_buffer format = {sizeof("NNNNN"), "NNNNN"}; 501 struct acpi_buffer state = {0, NULL}; 502 union acpi_object *psd = NULL; 503 struct acpi_psd_package *pdomain; 504 505 status = acpi_evaluate_object(pr->handle, "_PSD", NULL, &buffer); 506 if (ACPI_FAILURE(status)) { 507 return -ENODEV; 508 } 509 510 psd = buffer.pointer; 511 if (!psd || (psd->type != ACPI_TYPE_PACKAGE)) { 512 printk(KERN_ERR PREFIX "Invalid _PSD data\n"); 513 result = -EFAULT; 514 goto end; 515 } 516 517 if (psd->package.count != 1) { 518 printk(KERN_ERR PREFIX "Invalid _PSD data\n"); 519 result = -EFAULT; 520 goto end; 521 } 522 523 pdomain = &(pr->performance->domain_info); 524 525 state.length = sizeof(struct acpi_psd_package); 526 state.pointer = pdomain; 527 528 status = acpi_extract_package(&(psd->package.elements[0]), 529 &format, &state); 530 if (ACPI_FAILURE(status)) { 531 printk(KERN_ERR PREFIX "Invalid _PSD data\n"); 532 result = -EFAULT; 533 goto end; 534 } 535 536 if (pdomain->num_entries != ACPI_PSD_REV0_ENTRIES) { 537 printk(KERN_ERR PREFIX "Unknown _PSD:num_entries\n"); 538 result = -EFAULT; 539 goto end; 540 } 541 542 if (pdomain->revision != ACPI_PSD_REV0_REVISION) { 543 printk(KERN_ERR PREFIX "Unknown _PSD:revision\n"); 544 result = -EFAULT; 545 goto end; 546 } 547 548 if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL && 549 pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY && 550 pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) { 551 printk(KERN_ERR PREFIX "Invalid _PSD:coord_type\n"); 552 result = -EFAULT; 553 goto end; 554 } 555 end: 556 kfree(buffer.pointer); 557 return result; 558 } 559 560 int acpi_processor_preregister_performance( 561 struct acpi_processor_performance __percpu *performance) 562 { 563 int count, count_target; 564 int retval = 0; 565 unsigned int i, j; 566 cpumask_var_t covered_cpus; 567 struct acpi_processor *pr; 568 struct acpi_psd_package *pdomain; 569 struct acpi_processor *match_pr; 570 struct acpi_psd_package *match_pdomain; 571 572 if (!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL)) 573 return -ENOMEM; 574 575 mutex_lock(&performance_mutex); 576 577 /* 578 * Check if another driver has already registered, and abort before 579 * changing pr->performance if it has. Check input data as well. 580 */ 581 for_each_possible_cpu(i) { 582 pr = per_cpu(processors, i); 583 if (!pr) { 584 /* Look only at processors in ACPI namespace */ 585 continue; 586 } 587 588 if (pr->performance) { 589 retval = -EBUSY; 590 goto err_out; 591 } 592 593 if (!performance || !per_cpu_ptr(performance, i)) { 594 retval = -EINVAL; 595 goto err_out; 596 } 597 } 598 599 /* Call _PSD for all CPUs */ 600 for_each_possible_cpu(i) { 601 pr = per_cpu(processors, i); 602 if (!pr) 603 continue; 604 605 pr->performance = per_cpu_ptr(performance, i); 606 cpumask_set_cpu(i, pr->performance->shared_cpu_map); 607 if (acpi_processor_get_psd(pr)) { 608 retval = -EINVAL; 609 continue; 610 } 611 } 612 if (retval) 613 goto err_ret; 614 615 /* 616 * Now that we have _PSD data from all CPUs, lets setup P-state 617 * domain info. 618 */ 619 for_each_possible_cpu(i) { 620 pr = per_cpu(processors, i); 621 if (!pr) 622 continue; 623 624 if (cpumask_test_cpu(i, covered_cpus)) 625 continue; 626 627 pdomain = &(pr->performance->domain_info); 628 cpumask_set_cpu(i, pr->performance->shared_cpu_map); 629 cpumask_set_cpu(i, covered_cpus); 630 if (pdomain->num_processors <= 1) 631 continue; 632 633 /* Validate the Domain info */ 634 count_target = pdomain->num_processors; 635 count = 1; 636 if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ALL) 637 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ALL; 638 else if (pdomain->coord_type == DOMAIN_COORD_TYPE_HW_ALL) 639 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_HW; 640 else if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ANY) 641 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ANY; 642 643 for_each_possible_cpu(j) { 644 if (i == j) 645 continue; 646 647 match_pr = per_cpu(processors, j); 648 if (!match_pr) 649 continue; 650 651 match_pdomain = &(match_pr->performance->domain_info); 652 if (match_pdomain->domain != pdomain->domain) 653 continue; 654 655 /* Here i and j are in the same domain */ 656 657 if (match_pdomain->num_processors != count_target) { 658 retval = -EINVAL; 659 goto err_ret; 660 } 661 662 if (pdomain->coord_type != match_pdomain->coord_type) { 663 retval = -EINVAL; 664 goto err_ret; 665 } 666 667 cpumask_set_cpu(j, covered_cpus); 668 cpumask_set_cpu(j, pr->performance->shared_cpu_map); 669 count++; 670 } 671 672 for_each_possible_cpu(j) { 673 if (i == j) 674 continue; 675 676 match_pr = per_cpu(processors, j); 677 if (!match_pr) 678 continue; 679 680 match_pdomain = &(match_pr->performance->domain_info); 681 if (match_pdomain->domain != pdomain->domain) 682 continue; 683 684 match_pr->performance->shared_type = 685 pr->performance->shared_type; 686 cpumask_copy(match_pr->performance->shared_cpu_map, 687 pr->performance->shared_cpu_map); 688 } 689 } 690 691 err_ret: 692 for_each_possible_cpu(i) { 693 pr = per_cpu(processors, i); 694 if (!pr || !pr->performance) 695 continue; 696 697 /* Assume no coordination on any error parsing domain info */ 698 if (retval) { 699 cpumask_clear(pr->performance->shared_cpu_map); 700 cpumask_set_cpu(i, pr->performance->shared_cpu_map); 701 pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ALL; 702 } 703 pr->performance = NULL; /* Will be set for real in register */ 704 } 705 706 err_out: 707 mutex_unlock(&performance_mutex); 708 free_cpumask_var(covered_cpus); 709 return retval; 710 } 711 EXPORT_SYMBOL(acpi_processor_preregister_performance); 712 713 int 714 acpi_processor_register_performance(struct acpi_processor_performance 715 *performance, unsigned int cpu) 716 { 717 struct acpi_processor *pr; 718 719 if (!(acpi_processor_ppc_status & PPC_REGISTERED)) 720 return -EINVAL; 721 722 mutex_lock(&performance_mutex); 723 724 pr = per_cpu(processors, cpu); 725 if (!pr) { 726 mutex_unlock(&performance_mutex); 727 return -ENODEV; 728 } 729 730 if (pr->performance) { 731 mutex_unlock(&performance_mutex); 732 return -EBUSY; 733 } 734 735 WARN_ON(!performance); 736 737 pr->performance = performance; 738 739 if (acpi_processor_get_performance_info(pr)) { 740 pr->performance = NULL; 741 mutex_unlock(&performance_mutex); 742 return -EIO; 743 } 744 745 mutex_unlock(&performance_mutex); 746 return 0; 747 } 748 749 EXPORT_SYMBOL(acpi_processor_register_performance); 750 751 void 752 acpi_processor_unregister_performance(struct acpi_processor_performance 753 *performance, unsigned int cpu) 754 { 755 struct acpi_processor *pr; 756 757 mutex_lock(&performance_mutex); 758 759 pr = per_cpu(processors, cpu); 760 if (!pr) { 761 mutex_unlock(&performance_mutex); 762 return; 763 } 764 765 if (pr->performance) 766 kfree(pr->performance->states); 767 pr->performance = NULL; 768 769 mutex_unlock(&performance_mutex); 770 771 return; 772 } 773 774 EXPORT_SYMBOL(acpi_processor_unregister_performance); 775