1 /* 2 * acpi_processor.c - ACPI processor enumeration support 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 * Copyright (C) 2013, Intel Corporation 9 * Rafael J. Wysocki <rafael.j.wysocki@intel.com> 10 * 11 * This program is free software; you can redistribute it and/or modify it 12 * under the terms of the GNU General Public License version 2 as published 13 * by the Free Software Foundation. 14 */ 15 16 #include <linux/acpi.h> 17 #include <linux/device.h> 18 #include <linux/kernel.h> 19 #include <linux/module.h> 20 #include <linux/pci.h> 21 22 #include <acpi/processor.h> 23 24 #include <asm/cpu.h> 25 26 #include "internal.h" 27 28 #define _COMPONENT ACPI_PROCESSOR_COMPONENT 29 30 ACPI_MODULE_NAME("processor"); 31 32 DEFINE_PER_CPU(struct acpi_processor *, processors); 33 EXPORT_PER_CPU_SYMBOL(processors); 34 35 /* -------------------------------------------------------------------------- 36 Errata Handling 37 -------------------------------------------------------------------------- */ 38 39 struct acpi_processor_errata errata __read_mostly; 40 EXPORT_SYMBOL_GPL(errata); 41 42 static int acpi_processor_errata_piix4(struct pci_dev *dev) 43 { 44 u8 value1 = 0; 45 u8 value2 = 0; 46 47 48 if (!dev) 49 return -EINVAL; 50 51 /* 52 * Note that 'dev' references the PIIX4 ACPI Controller. 53 */ 54 55 switch (dev->revision) { 56 case 0: 57 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 A-step\n")); 58 break; 59 case 1: 60 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 B-step\n")); 61 break; 62 case 2: 63 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4E\n")); 64 break; 65 case 3: 66 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4M\n")); 67 break; 68 default: 69 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found unknown PIIX4\n")); 70 break; 71 } 72 73 switch (dev->revision) { 74 75 case 0: /* PIIX4 A-step */ 76 case 1: /* PIIX4 B-step */ 77 /* 78 * See specification changes #13 ("Manual Throttle Duty Cycle") 79 * and #14 ("Enabling and Disabling Manual Throttle"), plus 80 * erratum #5 ("STPCLK# Deassertion Time") from the January 81 * 2002 PIIX4 specification update. Applies to only older 82 * PIIX4 models. 83 */ 84 errata.piix4.throttle = 1; 85 86 case 2: /* PIIX4E */ 87 case 3: /* PIIX4M */ 88 /* 89 * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA 90 * Livelock") from the January 2002 PIIX4 specification update. 91 * Applies to all PIIX4 models. 92 */ 93 94 /* 95 * BM-IDE 96 * ------ 97 * Find the PIIX4 IDE Controller and get the Bus Master IDE 98 * Status register address. We'll use this later to read 99 * each IDE controller's DMA status to make sure we catch all 100 * DMA activity. 101 */ 102 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL, 103 PCI_DEVICE_ID_INTEL_82371AB, 104 PCI_ANY_ID, PCI_ANY_ID, NULL); 105 if (dev) { 106 errata.piix4.bmisx = pci_resource_start(dev, 4); 107 pci_dev_put(dev); 108 } 109 110 /* 111 * Type-F DMA 112 * ---------- 113 * Find the PIIX4 ISA Controller and read the Motherboard 114 * DMA controller's status to see if Type-F (Fast) DMA mode 115 * is enabled (bit 7) on either channel. Note that we'll 116 * disable C3 support if this is enabled, as some legacy 117 * devices won't operate well if fast DMA is disabled. 118 */ 119 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL, 120 PCI_DEVICE_ID_INTEL_82371AB_0, 121 PCI_ANY_ID, PCI_ANY_ID, NULL); 122 if (dev) { 123 pci_read_config_byte(dev, 0x76, &value1); 124 pci_read_config_byte(dev, 0x77, &value2); 125 if ((value1 & 0x80) || (value2 & 0x80)) 126 errata.piix4.fdma = 1; 127 pci_dev_put(dev); 128 } 129 130 break; 131 } 132 133 if (errata.piix4.bmisx) 134 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 135 "Bus master activity detection (BM-IDE) erratum enabled\n")); 136 if (errata.piix4.fdma) 137 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 138 "Type-F DMA livelock erratum (C3 disabled)\n")); 139 140 return 0; 141 } 142 143 static int acpi_processor_errata(void) 144 { 145 int result = 0; 146 struct pci_dev *dev = NULL; 147 148 /* 149 * PIIX4 150 */ 151 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL, 152 PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID, 153 PCI_ANY_ID, NULL); 154 if (dev) { 155 result = acpi_processor_errata_piix4(dev); 156 pci_dev_put(dev); 157 } 158 159 return result; 160 } 161 162 /* -------------------------------------------------------------------------- 163 Initialization 164 -------------------------------------------------------------------------- */ 165 166 #ifdef CONFIG_ACPI_HOTPLUG_CPU 167 int __weak acpi_map_cpu(acpi_handle handle, 168 phys_cpuid_t physid, int *pcpu) 169 { 170 return -ENODEV; 171 } 172 173 int __weak acpi_unmap_cpu(int cpu) 174 { 175 return -ENODEV; 176 } 177 178 int __weak arch_register_cpu(int cpu) 179 { 180 return -ENODEV; 181 } 182 183 void __weak arch_unregister_cpu(int cpu) {} 184 185 static int acpi_processor_hotadd_init(struct acpi_processor *pr) 186 { 187 unsigned long long sta; 188 acpi_status status; 189 int ret; 190 191 if (invalid_phys_cpuid(pr->phys_id)) 192 return -ENODEV; 193 194 status = acpi_evaluate_integer(pr->handle, "_STA", NULL, &sta); 195 if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_PRESENT)) 196 return -ENODEV; 197 198 cpu_maps_update_begin(); 199 cpu_hotplug_begin(); 200 201 ret = acpi_map_cpu(pr->handle, pr->phys_id, &pr->id); 202 if (ret) 203 goto out; 204 205 ret = arch_register_cpu(pr->id); 206 if (ret) { 207 acpi_unmap_cpu(pr->id); 208 goto out; 209 } 210 211 /* 212 * CPU got hot-added, but cpu_data is not initialized yet. Set a flag 213 * to delay cpu_idle/throttling initialization and do it when the CPU 214 * gets online for the first time. 215 */ 216 pr_info("CPU%d has been hot-added\n", pr->id); 217 pr->flags.need_hotplug_init = 1; 218 219 out: 220 cpu_hotplug_done(); 221 cpu_maps_update_done(); 222 return ret; 223 } 224 #else 225 static inline int acpi_processor_hotadd_init(struct acpi_processor *pr) 226 { 227 return -ENODEV; 228 } 229 #endif /* CONFIG_ACPI_HOTPLUG_CPU */ 230 231 static int acpi_processor_get_info(struct acpi_device *device) 232 { 233 union acpi_object object = { 0 }; 234 struct acpi_buffer buffer = { sizeof(union acpi_object), &object }; 235 struct acpi_processor *pr = acpi_driver_data(device); 236 int device_declaration = 0; 237 acpi_status status = AE_OK; 238 static int cpu0_initialized; 239 unsigned long long value; 240 241 acpi_processor_errata(); 242 243 /* 244 * Check to see if we have bus mastering arbitration control. This 245 * is required for proper C3 usage (to maintain cache coherency). 246 */ 247 if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) { 248 pr->flags.bm_control = 1; 249 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 250 "Bus mastering arbitration control present\n")); 251 } else 252 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 253 "No bus mastering arbitration control\n")); 254 255 if (!strcmp(acpi_device_hid(device), ACPI_PROCESSOR_OBJECT_HID)) { 256 /* Declared with "Processor" statement; match ProcessorID */ 257 status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer); 258 if (ACPI_FAILURE(status)) { 259 dev_err(&device->dev, 260 "Failed to evaluate processor object (0x%x)\n", 261 status); 262 return -ENODEV; 263 } 264 265 pr->acpi_id = object.processor.proc_id; 266 } else { 267 /* 268 * Declared with "Device" statement; match _UID. 269 * Note that we don't handle string _UIDs yet. 270 */ 271 status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID, 272 NULL, &value); 273 if (ACPI_FAILURE(status)) { 274 dev_err(&device->dev, 275 "Failed to evaluate processor _UID (0x%x)\n", 276 status); 277 return -ENODEV; 278 } 279 device_declaration = 1; 280 pr->acpi_id = value; 281 } 282 283 pr->phys_id = acpi_get_phys_id(pr->handle, device_declaration, 284 pr->acpi_id); 285 if (invalid_phys_cpuid(pr->phys_id)) 286 acpi_handle_debug(pr->handle, "failed to get CPU physical ID.\n"); 287 288 pr->id = acpi_map_cpuid(pr->phys_id, pr->acpi_id); 289 if (!cpu0_initialized && !acpi_has_cpu_in_madt()) { 290 cpu0_initialized = 1; 291 /* 292 * Handle UP system running SMP kernel, with no CPU 293 * entry in MADT 294 */ 295 if (invalid_logical_cpuid(pr->id) && (num_online_cpus() == 1)) 296 pr->id = 0; 297 } 298 299 /* 300 * Extra Processor objects may be enumerated on MP systems with 301 * less than the max # of CPUs. They should be ignored _iff 302 * they are physically not present. 303 */ 304 if (invalid_logical_cpuid(pr->id)) { 305 int ret = acpi_processor_hotadd_init(pr); 306 if (ret) 307 return ret; 308 } 309 310 /* 311 * On some boxes several processors use the same processor bus id. 312 * But they are located in different scope. For example: 313 * \_SB.SCK0.CPU0 314 * \_SB.SCK1.CPU0 315 * Rename the processor device bus id. And the new bus id will be 316 * generated as the following format: 317 * CPU+CPU ID. 318 */ 319 sprintf(acpi_device_bid(device), "CPU%X", pr->id); 320 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id, 321 pr->acpi_id)); 322 323 if (!object.processor.pblk_address) 324 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n")); 325 else if (object.processor.pblk_length != 6) 326 dev_err(&device->dev, "Invalid PBLK length [%d]\n", 327 object.processor.pblk_length); 328 else { 329 pr->throttling.address = object.processor.pblk_address; 330 pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset; 331 pr->throttling.duty_width = acpi_gbl_FADT.duty_width; 332 333 pr->pblk = object.processor.pblk_address; 334 } 335 336 /* 337 * If ACPI describes a slot number for this CPU, we can use it to 338 * ensure we get the right value in the "physical id" field 339 * of /proc/cpuinfo 340 */ 341 status = acpi_evaluate_integer(pr->handle, "_SUN", NULL, &value); 342 if (ACPI_SUCCESS(status)) 343 arch_fix_phys_package_id(pr->id, value); 344 345 return 0; 346 } 347 348 /* 349 * Do not put anything in here which needs the core to be online. 350 * For example MSR access or setting up things which check for cpuinfo_x86 351 * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc. 352 * Such things have to be put in and set up by the processor driver's .probe(). 353 */ 354 static DEFINE_PER_CPU(void *, processor_device_array); 355 356 static int acpi_processor_add(struct acpi_device *device, 357 const struct acpi_device_id *id) 358 { 359 struct acpi_processor *pr; 360 struct device *dev; 361 int result = 0; 362 363 pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL); 364 if (!pr) 365 return -ENOMEM; 366 367 if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) { 368 result = -ENOMEM; 369 goto err_free_pr; 370 } 371 372 pr->handle = device->handle; 373 strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME); 374 strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS); 375 device->driver_data = pr; 376 377 result = acpi_processor_get_info(device); 378 if (result) /* Processor is not physically present or unavailable */ 379 return 0; 380 381 #ifdef CONFIG_SMP 382 if (pr->id >= setup_max_cpus && pr->id != 0) 383 return 0; 384 #endif 385 386 BUG_ON(pr->id >= nr_cpu_ids); 387 388 /* 389 * Buggy BIOS check. 390 * ACPI id of processors can be reported wrongly by the BIOS. 391 * Don't trust it blindly 392 */ 393 if (per_cpu(processor_device_array, pr->id) != NULL && 394 per_cpu(processor_device_array, pr->id) != device) { 395 dev_warn(&device->dev, 396 "BIOS reported wrong ACPI id %d for the processor\n", 397 pr->id); 398 /* Give up, but do not abort the namespace scan. */ 399 goto err; 400 } 401 /* 402 * processor_device_array is not cleared on errors to allow buggy BIOS 403 * checks. 404 */ 405 per_cpu(processor_device_array, pr->id) = device; 406 per_cpu(processors, pr->id) = pr; 407 408 dev = get_cpu_device(pr->id); 409 if (!dev) { 410 result = -ENODEV; 411 goto err; 412 } 413 414 result = acpi_bind_one(dev, device); 415 if (result) 416 goto err; 417 418 pr->dev = dev; 419 420 /* Trigger the processor driver's .probe() if present. */ 421 if (device_attach(dev) >= 0) 422 return 1; 423 424 dev_err(dev, "Processor driver could not be attached\n"); 425 acpi_unbind_one(dev); 426 427 err: 428 free_cpumask_var(pr->throttling.shared_cpu_map); 429 device->driver_data = NULL; 430 per_cpu(processors, pr->id) = NULL; 431 err_free_pr: 432 kfree(pr); 433 return result; 434 } 435 436 #ifdef CONFIG_ACPI_HOTPLUG_CPU 437 /* -------------------------------------------------------------------------- 438 Removal 439 -------------------------------------------------------------------------- */ 440 441 static void acpi_processor_remove(struct acpi_device *device) 442 { 443 struct acpi_processor *pr; 444 445 if (!device || !acpi_driver_data(device)) 446 return; 447 448 pr = acpi_driver_data(device); 449 if (pr->id >= nr_cpu_ids) 450 goto out; 451 452 /* 453 * The only reason why we ever get here is CPU hot-removal. The CPU is 454 * already offline and the ACPI device removal locking prevents it from 455 * being put back online at this point. 456 * 457 * Unbind the driver from the processor device and detach it from the 458 * ACPI companion object. 459 */ 460 device_release_driver(pr->dev); 461 acpi_unbind_one(pr->dev); 462 463 /* Clean up. */ 464 per_cpu(processor_device_array, pr->id) = NULL; 465 per_cpu(processors, pr->id) = NULL; 466 467 cpu_maps_update_begin(); 468 cpu_hotplug_begin(); 469 470 /* Remove the CPU. */ 471 arch_unregister_cpu(pr->id); 472 acpi_unmap_cpu(pr->id); 473 474 cpu_hotplug_done(); 475 cpu_maps_update_done(); 476 477 try_offline_node(cpu_to_node(pr->id)); 478 479 out: 480 free_cpumask_var(pr->throttling.shared_cpu_map); 481 kfree(pr); 482 } 483 #endif /* CONFIG_ACPI_HOTPLUG_CPU */ 484 485 #ifdef CONFIG_X86 486 static bool acpi_hwp_native_thermal_lvt_set; 487 static acpi_status __init acpi_hwp_native_thermal_lvt_osc(acpi_handle handle, 488 u32 lvl, 489 void *context, 490 void **rv) 491 { 492 u8 sb_uuid_str[] = "4077A616-290C-47BE-9EBD-D87058713953"; 493 u32 capbuf[2]; 494 struct acpi_osc_context osc_context = { 495 .uuid_str = sb_uuid_str, 496 .rev = 1, 497 .cap.length = 8, 498 .cap.pointer = capbuf, 499 }; 500 501 if (acpi_hwp_native_thermal_lvt_set) 502 return AE_CTRL_TERMINATE; 503 504 capbuf[0] = 0x0000; 505 capbuf[1] = 0x1000; /* set bit 12 */ 506 507 if (ACPI_SUCCESS(acpi_run_osc(handle, &osc_context))) { 508 if (osc_context.ret.pointer && osc_context.ret.length > 1) { 509 u32 *capbuf_ret = osc_context.ret.pointer; 510 511 if (capbuf_ret[1] & 0x1000) { 512 acpi_handle_info(handle, 513 "_OSC native thermal LVT Acked\n"); 514 acpi_hwp_native_thermal_lvt_set = true; 515 } 516 } 517 kfree(osc_context.ret.pointer); 518 } 519 520 return AE_OK; 521 } 522 523 void __init acpi_early_processor_osc(void) 524 { 525 if (boot_cpu_has(X86_FEATURE_HWP)) { 526 acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT, 527 ACPI_UINT32_MAX, 528 acpi_hwp_native_thermal_lvt_osc, 529 NULL, NULL, NULL); 530 acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID, 531 acpi_hwp_native_thermal_lvt_osc, 532 NULL, NULL); 533 } 534 } 535 #endif 536 537 /* 538 * The following ACPI IDs are known to be suitable for representing as 539 * processor devices. 540 */ 541 static const struct acpi_device_id processor_device_ids[] = { 542 543 { ACPI_PROCESSOR_OBJECT_HID, }, 544 { ACPI_PROCESSOR_DEVICE_HID, }, 545 546 { } 547 }; 548 549 static struct acpi_scan_handler processor_handler = { 550 .ids = processor_device_ids, 551 .attach = acpi_processor_add, 552 #ifdef CONFIG_ACPI_HOTPLUG_CPU 553 .detach = acpi_processor_remove, 554 #endif 555 .hotplug = { 556 .enabled = true, 557 }, 558 }; 559 560 static int acpi_processor_container_attach(struct acpi_device *dev, 561 const struct acpi_device_id *id) 562 { 563 return 1; 564 } 565 566 static const struct acpi_device_id processor_container_ids[] = { 567 { ACPI_PROCESSOR_CONTAINER_HID, }, 568 { } 569 }; 570 571 static struct acpi_scan_handler processor_container_handler = { 572 .ids = processor_container_ids, 573 .attach = acpi_processor_container_attach, 574 }; 575 576 void __init acpi_processor_init(void) 577 { 578 acpi_scan_add_handler_with_hotplug(&processor_handler, "processor"); 579 acpi_scan_add_handler(&processor_container_handler); 580 } 581