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