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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 | // SPDX-License-Identifier: GPL-2.0-or-later /* * processor_perflib.c - ACPI Processor P-States Library ($Revision: 71 $) * * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com> * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> * Copyright (C) 2004 Dominik Brodowski <linux@brodo.de> * Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> * - Added processor hotplug support */ #include <linux/kernel.h> #include <linux/module.h> #include <linux/init.h> #include <linux/cpufreq.h> #include <linux/slab.h> #include <linux/acpi.h> #include <acpi/processor.h> #ifdef CONFIG_X86 #include <asm/cpufeature.h> #endif #define PREFIX "ACPI: " #define ACPI_PROCESSOR_CLASS "processor" #define ACPI_PROCESSOR_FILE_PERFORMANCE "performance" #define _COMPONENT ACPI_PROCESSOR_COMPONENT ACPI_MODULE_NAME("processor_perflib"); static DEFINE_MUTEX(performance_mutex); /* * _PPC support is implemented as a CPUfreq policy notifier: * This means each time a CPUfreq driver registered also with * the ACPI core is asked to change the speed policy, the maximum * value is adjusted so that it is within the platform limit. * * Also, when a new platform limit value is detected, the CPUfreq * policy is adjusted accordingly. */ /* ignore_ppc: * -1 -> cpufreq low level drivers not initialized -> _PSS, etc. not called yet * ignore _PPC * 0 -> cpufreq low level drivers initialized -> consider _PPC values * 1 -> ignore _PPC totally -> forced by user through boot param */ static int ignore_ppc = -1; module_param(ignore_ppc, int, 0644); MODULE_PARM_DESC(ignore_ppc, "If the frequency of your machine gets wrongly" \ "limited by BIOS, this should help"); #define PPC_REGISTERED 1 #define PPC_IN_USE 2 static int acpi_processor_ppc_status; static int acpi_processor_ppc_notifier(struct notifier_block *nb, unsigned long event, void *data) { struct cpufreq_policy *policy = data; struct acpi_processor *pr; unsigned int ppc = 0; if (ignore_ppc < 0) ignore_ppc = 0; if (ignore_ppc) return 0; if (event != CPUFREQ_ADJUST) return 0; mutex_lock(&performance_mutex); pr = per_cpu(processors, policy->cpu); if (!pr || !pr->performance) goto out; ppc = (unsigned int)pr->performance_platform_limit; if (ppc >= pr->performance->state_count) goto out; cpufreq_verify_within_limits(policy, 0, pr->performance->states[ppc]. core_frequency * 1000); out: mutex_unlock(&performance_mutex); return 0; } static struct notifier_block acpi_ppc_notifier_block = { .notifier_call = acpi_processor_ppc_notifier, }; static int acpi_processor_get_platform_limit(struct acpi_processor *pr) { acpi_status status = 0; unsigned long long ppc = 0; if (!pr) return -EINVAL; /* * _PPC indicates the maximum state currently supported by the platform * (e.g. 0 = states 0..n; 1 = states 1..n; etc. */ status = acpi_evaluate_integer(pr->handle, "_PPC", NULL, &ppc); if (status != AE_NOT_FOUND) acpi_processor_ppc_status |= PPC_IN_USE; if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) { ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PPC")); return -ENODEV; } pr_debug("CPU %d: _PPC is %d - frequency %s limited\n", pr->id, (int)ppc, ppc ? "" : "not"); pr->performance_platform_limit = (int)ppc; return 0; } #define ACPI_PROCESSOR_NOTIFY_PERFORMANCE 0x80 /* * acpi_processor_ppc_ost: Notify firmware the _PPC evaluation status * @handle: ACPI processor handle * @status: the status code of _PPC evaluation * 0: success. OSPM is now using the performance state specificed. * 1: failure. OSPM has not changed the number of P-states in use */ static void acpi_processor_ppc_ost(acpi_handle handle, int status) { if (acpi_has_method(handle, "_OST")) acpi_evaluate_ost(handle, ACPI_PROCESSOR_NOTIFY_PERFORMANCE, status, NULL); } void acpi_processor_ppc_has_changed(struct acpi_processor *pr, int event_flag) { int ret; if (ignore_ppc || !pr->performance) { /* * Only when it is notification event, the _OST object * will be evaluated. Otherwise it is skipped. */ if (event_flag) acpi_processor_ppc_ost(pr->handle, 1); return; } ret = acpi_processor_get_platform_limit(pr); /* * Only when it is notification event, the _OST object * will be evaluated. Otherwise it is skipped. */ if (event_flag) { if (ret < 0) acpi_processor_ppc_ost(pr->handle, 1); else acpi_processor_ppc_ost(pr->handle, 0); } if (ret >= 0) cpufreq_update_limits(pr->id); } int acpi_processor_get_bios_limit(int cpu, unsigned int *limit) { struct acpi_processor *pr; pr = per_cpu(processors, cpu); if (!pr || !pr->performance || !pr->performance->state_count) return -ENODEV; *limit = pr->performance->states[pr->performance_platform_limit]. core_frequency * 1000; return 0; } EXPORT_SYMBOL(acpi_processor_get_bios_limit); void acpi_processor_ppc_init(void) { if (!cpufreq_register_notifier (&acpi_ppc_notifier_block, CPUFREQ_POLICY_NOTIFIER)) acpi_processor_ppc_status |= PPC_REGISTERED; else printk(KERN_DEBUG "Warning: Processor Platform Limit not supported.\n"); } void acpi_processor_ppc_exit(void) { if (acpi_processor_ppc_status & PPC_REGISTERED) cpufreq_unregister_notifier(&acpi_ppc_notifier_block, CPUFREQ_POLICY_NOTIFIER); acpi_processor_ppc_status &= ~PPC_REGISTERED; } static int acpi_processor_get_performance_control(struct acpi_processor *pr) { int result = 0; acpi_status status = 0; struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; union acpi_object *pct = NULL; union acpi_object obj = { 0 }; status = acpi_evaluate_object(pr->handle, "_PCT", NULL, &buffer); if (ACPI_FAILURE(status)) { ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PCT")); return -ENODEV; } pct = (union acpi_object *)buffer.pointer; if (!pct || (pct->type != ACPI_TYPE_PACKAGE) || (pct->package.count != 2)) { printk(KERN_ERR PREFIX "Invalid _PCT data\n"); result = -EFAULT; goto end; } /* * control_register */ obj = pct->package.elements[0]; if ((obj.type != ACPI_TYPE_BUFFER) || (obj.buffer.length < sizeof(struct acpi_pct_register)) || (obj.buffer.pointer == NULL)) { printk(KERN_ERR PREFIX "Invalid _PCT data (control_register)\n"); result = -EFAULT; goto end; } memcpy(&pr->performance->control_register, obj.buffer.pointer, sizeof(struct acpi_pct_register)); /* * status_register */ obj = pct->package.elements[1]; if ((obj.type != ACPI_TYPE_BUFFER) || (obj.buffer.length < sizeof(struct acpi_pct_register)) || (obj.buffer.pointer == NULL)) { printk(KERN_ERR PREFIX "Invalid _PCT data (status_register)\n"); result = -EFAULT; goto end; } memcpy(&pr->performance->status_register, obj.buffer.pointer, sizeof(struct acpi_pct_register)); end: kfree(buffer.pointer); return result; } #ifdef CONFIG_X86 /* * Some AMDs have 50MHz frequency multiples, but only provide 100MHz rounding * in their ACPI data. Calculate the real values and fix up the _PSS data. */ static void amd_fixup_frequency(struct acpi_processor_px *px, int i) { u32 hi, lo, fid, did; int index = px->control & 0x00000007; if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD) return; if ((boot_cpu_data.x86 == 0x10 && boot_cpu_data.x86_model < 10) || boot_cpu_data.x86 == 0x11) { rdmsr(MSR_AMD_PSTATE_DEF_BASE + index, lo, hi); /* * MSR C001_0064+: * Bit 63: PstateEn. Read-write. If set, the P-state is valid. */ if (!(hi & BIT(31))) return; fid = lo & 0x3f; did = (lo >> 6) & 7; if (boot_cpu_data.x86 == 0x10) px->core_frequency = (100 * (fid + 0x10)) >> did; else px->core_frequency = (100 * (fid + 8)) >> did; } } #else static void amd_fixup_frequency(struct acpi_processor_px *px, int i) {}; #endif static int acpi_processor_get_performance_states(struct acpi_processor *pr) { int result = 0; acpi_status status = AE_OK; struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL }; struct acpi_buffer format = { sizeof("NNNNNN"), "NNNNNN" }; struct acpi_buffer state = { 0, NULL }; union acpi_object *pss = NULL; int i; int last_invalid = -1; status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer); if (ACPI_FAILURE(status)) { ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PSS")); return -ENODEV; } pss = buffer.pointer; if (!pss || (pss->type != ACPI_TYPE_PACKAGE)) { printk(KERN_ERR PREFIX "Invalid _PSS data\n"); result = -EFAULT; goto end; } ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d performance states\n", pss->package.count)); pr->performance->state_count = pss->package.count; pr->performance->states = kmalloc_array(pss->package.count, sizeof(struct acpi_processor_px), GFP_KERNEL); if (!pr->performance->states) { result = -ENOMEM; goto end; } for (i = 0; i < pr->performance->state_count; i++) { struct acpi_processor_px *px = &(pr->performance->states[i]); state.length = sizeof(struct acpi_processor_px); state.pointer = px; ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i)); status = acpi_extract_package(&(pss->package.elements[i]), &format, &state); if (ACPI_FAILURE(status)) { ACPI_EXCEPTION((AE_INFO, status, "Invalid _PSS data")); result = -EFAULT; kfree(pr->performance->states); goto end; } amd_fixup_frequency(px, i); ACPI_DEBUG_PRINT((ACPI_DB_INFO, "State [%d]: core_frequency[%d] power[%d] transition_latency[%d] bus_master_latency[%d] control[0x%x] status[0x%x]\n", i, (u32) px->core_frequency, (u32) px->power, (u32) px->transition_latency, (u32) px->bus_master_latency, (u32) px->control, (u32) px->status)); /* * Check that ACPI's u64 MHz will be valid as u32 KHz in cpufreq */ if (!px->core_frequency || ((u32)(px->core_frequency * 1000) != (px->core_frequency * 1000))) { printk(KERN_ERR FW_BUG PREFIX "Invalid BIOS _PSS frequency found for processor %d: 0x%llx MHz\n", pr->id, px->core_frequency); if (last_invalid == -1) last_invalid = i; } else { if (last_invalid != -1) { /* * Copy this valid entry over last_invalid entry */ memcpy(&(pr->performance->states[last_invalid]), px, sizeof(struct acpi_processor_px)); ++last_invalid; } } } if (last_invalid == 0) { printk(KERN_ERR FW_BUG PREFIX "No valid BIOS _PSS frequency found for processor %d\n", pr->id); result = -EFAULT; kfree(pr->performance->states); pr->performance->states = NULL; } if (last_invalid > 0) pr->performance->state_count = last_invalid; end: kfree(buffer.pointer); return result; } int acpi_processor_get_performance_info(struct acpi_processor *pr) { int result = 0; if (!pr || !pr->performance || !pr->handle) return -EINVAL; if (!acpi_has_method(pr->handle, "_PCT")) { ACPI_DEBUG_PRINT((ACPI_DB_INFO, "ACPI-based processor performance control unavailable\n")); return -ENODEV; } result = acpi_processor_get_performance_control(pr); if (result) goto update_bios; result = acpi_processor_get_performance_states(pr); if (result) goto update_bios; /* We need to call _PPC once when cpufreq starts */ if (ignore_ppc != 1) result = acpi_processor_get_platform_limit(pr); return result; /* * Having _PPC but missing frequencies (_PSS, _PCT) is a very good hint that * the BIOS is older than the CPU and does not know its frequencies */ update_bios: #ifdef CONFIG_X86 if (acpi_has_method(pr->handle, "_PPC")) { if(boot_cpu_has(X86_FEATURE_EST)) printk(KERN_WARNING FW_BUG "BIOS needs update for CPU " "frequency support\n"); } #endif return result; } EXPORT_SYMBOL_GPL(acpi_processor_get_performance_info); int acpi_processor_pstate_control(void) { acpi_status status; if (!acpi_gbl_FADT.smi_command || !acpi_gbl_FADT.pstate_control) return 0; ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Writing pstate_control [0x%x] to smi_command [0x%x]\n", acpi_gbl_FADT.pstate_control, acpi_gbl_FADT.smi_command)); status = acpi_os_write_port(acpi_gbl_FADT.smi_command, (u32)acpi_gbl_FADT.pstate_control, 8); if (ACPI_SUCCESS(status)) return 1; ACPI_EXCEPTION((AE_INFO, status, "Failed to write pstate_control [0x%x] to smi_command [0x%x]", acpi_gbl_FADT.pstate_control, acpi_gbl_FADT.smi_command)); return -EIO; } int acpi_processor_notify_smm(struct module *calling_module) { static int is_done = 0; int result; if (!(acpi_processor_ppc_status & PPC_REGISTERED)) return -EBUSY; if (!try_module_get(calling_module)) return -EINVAL; /* is_done is set to negative if an error occurred, * and to postitive if _no_ error occurred, but SMM * was already notified. This avoids double notification * which might lead to unexpected results... */ if (is_done > 0) { module_put(calling_module); return 0; } else if (is_done < 0) { module_put(calling_module); return is_done; } is_done = -EIO; result = acpi_processor_pstate_control(); if (!result) { ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No SMI port or pstate_control\n")); module_put(calling_module); return 0; } if (result < 0) { module_put(calling_module); return result; } /* Success. If there's no _PPC, we need to fear nothing, so * we can allow the cpufreq driver to be rmmod'ed. */ is_done = 1; if (!(acpi_processor_ppc_status & PPC_IN_USE)) module_put(calling_module); return 0; } EXPORT_SYMBOL(acpi_processor_notify_smm); int acpi_processor_get_psd(acpi_handle handle, struct acpi_psd_package *pdomain) { int result = 0; acpi_status status = AE_OK; struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL}; struct acpi_buffer format = {sizeof("NNNNN"), "NNNNN"}; struct acpi_buffer state = {0, NULL}; union acpi_object *psd = NULL; status = acpi_evaluate_object(handle, "_PSD", NULL, &buffer); if (ACPI_FAILURE(status)) { return -ENODEV; } psd = buffer.pointer; if (!psd || (psd->type != ACPI_TYPE_PACKAGE)) { printk(KERN_ERR PREFIX "Invalid _PSD data\n"); result = -EFAULT; goto end; } if (psd->package.count != 1) { printk(KERN_ERR PREFIX "Invalid _PSD data\n"); result = -EFAULT; goto end; } state.length = sizeof(struct acpi_psd_package); state.pointer = pdomain; status = acpi_extract_package(&(psd->package.elements[0]), &format, &state); if (ACPI_FAILURE(status)) { printk(KERN_ERR PREFIX "Invalid _PSD data\n"); result = -EFAULT; goto end; } if (pdomain->num_entries != ACPI_PSD_REV0_ENTRIES) { printk(KERN_ERR PREFIX "Unknown _PSD:num_entries\n"); result = -EFAULT; goto end; } if (pdomain->revision != ACPI_PSD_REV0_REVISION) { printk(KERN_ERR PREFIX "Unknown _PSD:revision\n"); result = -EFAULT; goto end; } if (pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ALL && pdomain->coord_type != DOMAIN_COORD_TYPE_SW_ANY && pdomain->coord_type != DOMAIN_COORD_TYPE_HW_ALL) { printk(KERN_ERR PREFIX "Invalid _PSD:coord_type\n"); result = -EFAULT; goto end; } end: kfree(buffer.pointer); return result; } EXPORT_SYMBOL(acpi_processor_get_psd); int acpi_processor_preregister_performance( struct acpi_processor_performance __percpu *performance) { int count_target; int retval = 0; unsigned int i, j; cpumask_var_t covered_cpus; struct acpi_processor *pr; struct acpi_psd_package *pdomain; struct acpi_processor *match_pr; struct acpi_psd_package *match_pdomain; if (!zalloc_cpumask_var(&covered_cpus, GFP_KERNEL)) return -ENOMEM; mutex_lock(&performance_mutex); /* * Check if another driver has already registered, and abort before * changing pr->performance if it has. Check input data as well. */ for_each_possible_cpu(i) { pr = per_cpu(processors, i); if (!pr) { /* Look only at processors in ACPI namespace */ continue; } if (pr->performance) { retval = -EBUSY; goto err_out; } if (!performance || !per_cpu_ptr(performance, i)) { retval = -EINVAL; goto err_out; } } /* Call _PSD for all CPUs */ for_each_possible_cpu(i) { pr = per_cpu(processors, i); if (!pr) continue; pr->performance = per_cpu_ptr(performance, i); cpumask_set_cpu(i, pr->performance->shared_cpu_map); pdomain = &(pr->performance->domain_info); if (acpi_processor_get_psd(pr->handle, pdomain)) { retval = -EINVAL; continue; } } if (retval) goto err_ret; /* * Now that we have _PSD data from all CPUs, lets setup P-state * domain info. */ for_each_possible_cpu(i) { pr = per_cpu(processors, i); if (!pr) continue; if (cpumask_test_cpu(i, covered_cpus)) continue; pdomain = &(pr->performance->domain_info); cpumask_set_cpu(i, pr->performance->shared_cpu_map); cpumask_set_cpu(i, covered_cpus); if (pdomain->num_processors <= 1) continue; /* Validate the Domain info */ count_target = pdomain->num_processors; if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ALL) pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ALL; else if (pdomain->coord_type == DOMAIN_COORD_TYPE_HW_ALL) pr->performance->shared_type = CPUFREQ_SHARED_TYPE_HW; else if (pdomain->coord_type == DOMAIN_COORD_TYPE_SW_ANY) pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ANY; for_each_possible_cpu(j) { if (i == j) continue; match_pr = per_cpu(processors, j); if (!match_pr) continue; match_pdomain = &(match_pr->performance->domain_info); if (match_pdomain->domain != pdomain->domain) continue; /* Here i and j are in the same domain */ if (match_pdomain->num_processors != count_target) { retval = -EINVAL; goto err_ret; } if (pdomain->coord_type != match_pdomain->coord_type) { retval = -EINVAL; goto err_ret; } cpumask_set_cpu(j, covered_cpus); cpumask_set_cpu(j, pr->performance->shared_cpu_map); } for_each_possible_cpu(j) { if (i == j) continue; match_pr = per_cpu(processors, j); if (!match_pr) continue; match_pdomain = &(match_pr->performance->domain_info); if (match_pdomain->domain != pdomain->domain) continue; match_pr->performance->shared_type = pr->performance->shared_type; cpumask_copy(match_pr->performance->shared_cpu_map, pr->performance->shared_cpu_map); } } err_ret: for_each_possible_cpu(i) { pr = per_cpu(processors, i); if (!pr || !pr->performance) continue; /* Assume no coordination on any error parsing domain info */ if (retval) { cpumask_clear(pr->performance->shared_cpu_map); cpumask_set_cpu(i, pr->performance->shared_cpu_map); pr->performance->shared_type = CPUFREQ_SHARED_TYPE_ALL; } pr->performance = NULL; /* Will be set for real in register */ } err_out: mutex_unlock(&performance_mutex); free_cpumask_var(covered_cpus); return retval; } EXPORT_SYMBOL(acpi_processor_preregister_performance); int acpi_processor_register_performance(struct acpi_processor_performance *performance, unsigned int cpu) { struct acpi_processor *pr; if (!(acpi_processor_ppc_status & PPC_REGISTERED)) return -EINVAL; mutex_lock(&performance_mutex); pr = per_cpu(processors, cpu); if (!pr) { mutex_unlock(&performance_mutex); return -ENODEV; } if (pr->performance) { mutex_unlock(&performance_mutex); return -EBUSY; } WARN_ON(!performance); pr->performance = performance; if (acpi_processor_get_performance_info(pr)) { pr->performance = NULL; mutex_unlock(&performance_mutex); return -EIO; } mutex_unlock(&performance_mutex); return 0; } EXPORT_SYMBOL(acpi_processor_register_performance); void acpi_processor_unregister_performance(unsigned int cpu) { struct acpi_processor *pr; mutex_lock(&performance_mutex); pr = per_cpu(processors, cpu); if (!pr) { mutex_unlock(&performance_mutex); return; } if (pr->performance) kfree(pr->performance->states); pr->performance = NULL; mutex_unlock(&performance_mutex); return; } EXPORT_SYMBOL(acpi_processor_unregister_performance); |