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