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Linux/drivers/acpi/acpi_processor.c

  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                  * We don't care about error returns - we just try to mark
337                  * these reserved so that nobody else is confused into thinking
338                  * that this region might be unused..
339                  *
340                  * (In particular, allocating the IO range for Cardbus)
341                  */
342                 request_region(pr->throttling.address, 6, "ACPI CPU throttle");
343         }
344 
345         /*
346          * If ACPI describes a slot number for this CPU, we can use it to
347          * ensure we get the right value in the "physical id" field
348          * of /proc/cpuinfo
349          */
350         status = acpi_evaluate_integer(pr->handle, "_SUN", NULL, &value);
351         if (ACPI_SUCCESS(status))
352                 arch_fix_phys_package_id(pr->id, value);
353 
354         return 0;
355 }
356 
357 /*
358  * Do not put anything in here which needs the core to be online.
359  * For example MSR access or setting up things which check for cpuinfo_x86
360  * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.
361  * Such things have to be put in and set up by the processor driver's .probe().
362  */
363 static DEFINE_PER_CPU(void *, processor_device_array);
364 
365 static int acpi_processor_add(struct acpi_device *device,
366                                         const struct acpi_device_id *id)
367 {
368         struct acpi_processor *pr;
369         struct device *dev;
370         int result = 0;
371 
372         pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
373         if (!pr)
374                 return -ENOMEM;
375 
376         if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) {
377                 result = -ENOMEM;
378                 goto err_free_pr;
379         }
380 
381         pr->handle = device->handle;
382         strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
383         strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
384         device->driver_data = pr;
385 
386         result = acpi_processor_get_info(device);
387         if (result) /* Processor is not physically present or unavailable */
388                 return 0;
389 
390 #ifdef CONFIG_SMP
391         if (pr->id >= setup_max_cpus && pr->id != 0)
392                 return 0;
393 #endif
394 
395         BUG_ON(pr->id >= nr_cpu_ids);
396 
397         /*
398          * Buggy BIOS check.
399          * ACPI id of processors can be reported wrongly by the BIOS.
400          * Don't trust it blindly
401          */
402         if (per_cpu(processor_device_array, pr->id) != NULL &&
403             per_cpu(processor_device_array, pr->id) != device) {
404                 dev_warn(&device->dev,
405                         "BIOS reported wrong ACPI id %d for the processor\n",
406                         pr->id);
407                 /* Give up, but do not abort the namespace scan. */
408                 goto err;
409         }
410         /*
411          * processor_device_array is not cleared on errors to allow buggy BIOS
412          * checks.
413          */
414         per_cpu(processor_device_array, pr->id) = device;
415         per_cpu(processors, pr->id) = pr;
416 
417         dev = get_cpu_device(pr->id);
418         if (!dev) {
419                 result = -ENODEV;
420                 goto err;
421         }
422 
423         result = acpi_bind_one(dev, device);
424         if (result)
425                 goto err;
426 
427         pr->dev = dev;
428 
429         /* Trigger the processor driver's .probe() if present. */
430         if (device_attach(dev) >= 0)
431                 return 1;
432 
433         dev_err(dev, "Processor driver could not be attached\n");
434         acpi_unbind_one(dev);
435 
436  err:
437         free_cpumask_var(pr->throttling.shared_cpu_map);
438         device->driver_data = NULL;
439         per_cpu(processors, pr->id) = NULL;
440  err_free_pr:
441         kfree(pr);
442         return result;
443 }
444 
445 #ifdef CONFIG_ACPI_HOTPLUG_CPU
446 /* --------------------------------------------------------------------------
447                                     Removal
448    -------------------------------------------------------------------------- */
449 
450 static void acpi_processor_remove(struct acpi_device *device)
451 {
452         struct acpi_processor *pr;
453 
454         if (!device || !acpi_driver_data(device))
455                 return;
456 
457         pr = acpi_driver_data(device);
458         if (pr->id >= nr_cpu_ids)
459                 goto out;
460 
461         /*
462          * The only reason why we ever get here is CPU hot-removal.  The CPU is
463          * already offline and the ACPI device removal locking prevents it from
464          * being put back online at this point.
465          *
466          * Unbind the driver from the processor device and detach it from the
467          * ACPI companion object.
468          */
469         device_release_driver(pr->dev);
470         acpi_unbind_one(pr->dev);
471 
472         /* Clean up. */
473         per_cpu(processor_device_array, pr->id) = NULL;
474         per_cpu(processors, pr->id) = NULL;
475 
476         cpu_maps_update_begin();
477         cpu_hotplug_begin();
478 
479         /* Remove the CPU. */
480         arch_unregister_cpu(pr->id);
481         acpi_unmap_cpu(pr->id);
482 
483         cpu_hotplug_done();
484         cpu_maps_update_done();
485 
486         try_offline_node(cpu_to_node(pr->id));
487 
488  out:
489         free_cpumask_var(pr->throttling.shared_cpu_map);
490         kfree(pr);
491 }
492 #endif /* CONFIG_ACPI_HOTPLUG_CPU */
493 
494 #ifdef CONFIG_X86
495 static bool acpi_hwp_native_thermal_lvt_set;
496 static acpi_status __init acpi_hwp_native_thermal_lvt_osc(acpi_handle handle,
497                                                           u32 lvl,
498                                                           void *context,
499                                                           void **rv)
500 {
501         u8 sb_uuid_str[] = "4077A616-290C-47BE-9EBD-D87058713953";
502         u32 capbuf[2];
503         struct acpi_osc_context osc_context = {
504                 .uuid_str = sb_uuid_str,
505                 .rev = 1,
506                 .cap.length = 8,
507                 .cap.pointer = capbuf,
508         };
509 
510         if (acpi_hwp_native_thermal_lvt_set)
511                 return AE_CTRL_TERMINATE;
512 
513         capbuf[0] = 0x0000;
514         capbuf[1] = 0x1000; /* set bit 12 */
515 
516         if (ACPI_SUCCESS(acpi_run_osc(handle, &osc_context))) {
517                 if (osc_context.ret.pointer && osc_context.ret.length > 1) {
518                         u32 *capbuf_ret = osc_context.ret.pointer;
519 
520                         if (capbuf_ret[1] & 0x1000) {
521                                 acpi_handle_info(handle,
522                                         "_OSC native thermal LVT Acked\n");
523                                 acpi_hwp_native_thermal_lvt_set = true;
524                         }
525                 }
526                 kfree(osc_context.ret.pointer);
527         }
528 
529         return AE_OK;
530 }
531 
532 void __init acpi_early_processor_osc(void)
533 {
534         if (boot_cpu_has(X86_FEATURE_HWP)) {
535                 acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT,
536                                     ACPI_UINT32_MAX,
537                                     acpi_hwp_native_thermal_lvt_osc,
538                                     NULL, NULL, NULL);
539                 acpi_get_devices(ACPI_PROCESSOR_DEVICE_HID,
540                                  acpi_hwp_native_thermal_lvt_osc,
541                                  NULL, NULL);
542         }
543 }
544 #endif
545 
546 /*
547  * The following ACPI IDs are known to be suitable for representing as
548  * processor devices.
549  */
550 static const struct acpi_device_id processor_device_ids[] = {
551 
552         { ACPI_PROCESSOR_OBJECT_HID, },
553         { ACPI_PROCESSOR_DEVICE_HID, },
554 
555         { }
556 };
557 
558 static struct acpi_scan_handler processor_handler = {
559         .ids = processor_device_ids,
560         .attach = acpi_processor_add,
561 #ifdef CONFIG_ACPI_HOTPLUG_CPU
562         .detach = acpi_processor_remove,
563 #endif
564         .hotplug = {
565                 .enabled = true,
566         },
567 };
568 
569 static int acpi_processor_container_attach(struct acpi_device *dev,
570                                            const struct acpi_device_id *id)
571 {
572         return 1;
573 }
574 
575 static const struct acpi_device_id processor_container_ids[] = {
576         { ACPI_PROCESSOR_CONTAINER_HID, },
577         { }
578 };
579 
580 static struct acpi_scan_handler processor_container_handler = {
581         .ids = processor_container_ids,
582         .attach = acpi_processor_container_attach,
583 };
584 
585 void __init acpi_processor_init(void)
586 {
587         acpi_scan_add_handler_with_hotplug(&processor_handler, "processor");
588         acpi_scan_add_handler(&processor_container_handler);
589 }
590 

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