xref: /linux/drivers/acpi/processor_core.c (revision f7511d5f66f01fc451747b24e79f3ada7a3af9af)
1 /*
2  * acpi_processor.c - ACPI Processor Driver ($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  *  This program is free software; you can redistribute it and/or modify
13  *  it under the terms of the GNU General Public License as published by
14  *  the Free Software Foundation; either version 2 of the License, or (at
15  *  your option) any later version.
16  *
17  *  This program is distributed in the hope that it will be useful, but
18  *  WITHOUT ANY WARRANTY; without even the implied warranty of
19  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
20  *  General Public License for more details.
21  *
22  *  You should have received a copy of the GNU General Public License along
23  *  with this program; if not, write to the Free Software Foundation, Inc.,
24  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
25  *
26  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
27  *  TBD:
28  *	1. Make # power states dynamic.
29  *	2. Support duty_cycle values that span bit 4.
30  *	3. Optimize by having scheduler determine business instead of
31  *	   having us try to calculate it here.
32  *	4. Need C1 timing -- must modify kernel (IRQ handler) to get this.
33  */
34 
35 #include <linux/kernel.h>
36 #include <linux/module.h>
37 #include <linux/init.h>
38 #include <linux/types.h>
39 #include <linux/pci.h>
40 #include <linux/pm.h>
41 #include <linux/cpufreq.h>
42 #include <linux/cpu.h>
43 #include <linux/proc_fs.h>
44 #include <linux/seq_file.h>
45 #include <linux/dmi.h>
46 #include <linux/moduleparam.h>
47 #include <linux/cpuidle.h>
48 
49 #include <asm/io.h>
50 #include <asm/system.h>
51 #include <asm/cpu.h>
52 #include <asm/delay.h>
53 #include <asm/uaccess.h>
54 #include <asm/processor.h>
55 #include <asm/smp.h>
56 #include <asm/acpi.h>
57 
58 #include <acpi/acpi_bus.h>
59 #include <acpi/acpi_drivers.h>
60 #include <acpi/processor.h>
61 
62 #define ACPI_PROCESSOR_COMPONENT	0x01000000
63 #define ACPI_PROCESSOR_CLASS		"processor"
64 #define ACPI_PROCESSOR_DEVICE_NAME	"Processor"
65 #define ACPI_PROCESSOR_FILE_INFO	"info"
66 #define ACPI_PROCESSOR_FILE_THROTTLING	"throttling"
67 #define ACPI_PROCESSOR_FILE_LIMIT	"limit"
68 #define ACPI_PROCESSOR_NOTIFY_PERFORMANCE 0x80
69 #define ACPI_PROCESSOR_NOTIFY_POWER	0x81
70 #define ACPI_PROCESSOR_NOTIFY_THROTTLING	0x82
71 
72 #define ACPI_PROCESSOR_LIMIT_USER	0
73 #define ACPI_PROCESSOR_LIMIT_THERMAL	1
74 
75 #define _COMPONENT		ACPI_PROCESSOR_COMPONENT
76 ACPI_MODULE_NAME("processor_core");
77 
78 MODULE_AUTHOR("Paul Diefenbaugh");
79 MODULE_DESCRIPTION("ACPI Processor Driver");
80 MODULE_LICENSE("GPL");
81 
82 static int acpi_processor_add(struct acpi_device *device);
83 static int acpi_processor_start(struct acpi_device *device);
84 static int acpi_processor_remove(struct acpi_device *device, int type);
85 static int acpi_processor_info_open_fs(struct inode *inode, struct file *file);
86 static void acpi_processor_notify(acpi_handle handle, u32 event, void *data);
87 static acpi_status acpi_processor_hotadd_init(acpi_handle handle, int *p_cpu);
88 static int acpi_processor_handle_eject(struct acpi_processor *pr);
89 extern int acpi_processor_tstate_has_changed(struct acpi_processor *pr);
90 
91 
92 static const struct acpi_device_id processor_device_ids[] = {
93 	{ACPI_PROCESSOR_HID, 0},
94 	{"", 0},
95 };
96 MODULE_DEVICE_TABLE(acpi, processor_device_ids);
97 
98 static struct acpi_driver acpi_processor_driver = {
99 	.name = "processor",
100 	.class = ACPI_PROCESSOR_CLASS,
101 	.ids = processor_device_ids,
102 	.ops = {
103 		.add = acpi_processor_add,
104 		.remove = acpi_processor_remove,
105 		.start = acpi_processor_start,
106 		.suspend = acpi_processor_suspend,
107 		.resume = acpi_processor_resume,
108 		},
109 };
110 
111 #define INSTALL_NOTIFY_HANDLER		1
112 #define UNINSTALL_NOTIFY_HANDLER	2
113 
114 static const struct file_operations acpi_processor_info_fops = {
115 	.owner = THIS_MODULE,
116 	.open = acpi_processor_info_open_fs,
117 	.read = seq_read,
118 	.llseek = seq_lseek,
119 	.release = single_release,
120 };
121 
122 struct acpi_processor *processors[NR_CPUS];
123 struct acpi_processor_errata errata __read_mostly;
124 
125 /* --------------------------------------------------------------------------
126                                 Errata Handling
127    -------------------------------------------------------------------------- */
128 
129 static int acpi_processor_errata_piix4(struct pci_dev *dev)
130 {
131 	u8 value1 = 0;
132 	u8 value2 = 0;
133 
134 
135 	if (!dev)
136 		return -EINVAL;
137 
138 	/*
139 	 * Note that 'dev' references the PIIX4 ACPI Controller.
140 	 */
141 
142 	switch (dev->revision) {
143 	case 0:
144 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 A-step\n"));
145 		break;
146 	case 1:
147 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 B-step\n"));
148 		break;
149 	case 2:
150 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4E\n"));
151 		break;
152 	case 3:
153 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4M\n"));
154 		break;
155 	default:
156 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found unknown PIIX4\n"));
157 		break;
158 	}
159 
160 	switch (dev->revision) {
161 
162 	case 0:		/* PIIX4 A-step */
163 	case 1:		/* PIIX4 B-step */
164 		/*
165 		 * See specification changes #13 ("Manual Throttle Duty Cycle")
166 		 * and #14 ("Enabling and Disabling Manual Throttle"), plus
167 		 * erratum #5 ("STPCLK# Deassertion Time") from the January
168 		 * 2002 PIIX4 specification update.  Applies to only older
169 		 * PIIX4 models.
170 		 */
171 		errata.piix4.throttle = 1;
172 
173 	case 2:		/* PIIX4E */
174 	case 3:		/* PIIX4M */
175 		/*
176 		 * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA
177 		 * Livelock") from the January 2002 PIIX4 specification update.
178 		 * Applies to all PIIX4 models.
179 		 */
180 
181 		/*
182 		 * BM-IDE
183 		 * ------
184 		 * Find the PIIX4 IDE Controller and get the Bus Master IDE
185 		 * Status register address.  We'll use this later to read
186 		 * each IDE controller's DMA status to make sure we catch all
187 		 * DMA activity.
188 		 */
189 		dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
190 				     PCI_DEVICE_ID_INTEL_82371AB,
191 				     PCI_ANY_ID, PCI_ANY_ID, NULL);
192 		if (dev) {
193 			errata.piix4.bmisx = pci_resource_start(dev, 4);
194 			pci_dev_put(dev);
195 		}
196 
197 		/*
198 		 * Type-F DMA
199 		 * ----------
200 		 * Find the PIIX4 ISA Controller and read the Motherboard
201 		 * DMA controller's status to see if Type-F (Fast) DMA mode
202 		 * is enabled (bit 7) on either channel.  Note that we'll
203 		 * disable C3 support if this is enabled, as some legacy
204 		 * devices won't operate well if fast DMA is disabled.
205 		 */
206 		dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
207 				     PCI_DEVICE_ID_INTEL_82371AB_0,
208 				     PCI_ANY_ID, PCI_ANY_ID, NULL);
209 		if (dev) {
210 			pci_read_config_byte(dev, 0x76, &value1);
211 			pci_read_config_byte(dev, 0x77, &value2);
212 			if ((value1 & 0x80) || (value2 & 0x80))
213 				errata.piix4.fdma = 1;
214 			pci_dev_put(dev);
215 		}
216 
217 		break;
218 	}
219 
220 	if (errata.piix4.bmisx)
221 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
222 				  "Bus master activity detection (BM-IDE) erratum enabled\n"));
223 	if (errata.piix4.fdma)
224 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
225 				  "Type-F DMA livelock erratum (C3 disabled)\n"));
226 
227 	return 0;
228 }
229 
230 static int acpi_processor_errata(struct acpi_processor *pr)
231 {
232 	int result = 0;
233 	struct pci_dev *dev = NULL;
234 
235 
236 	if (!pr)
237 		return -EINVAL;
238 
239 	/*
240 	 * PIIX4
241 	 */
242 	dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
243 			     PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID,
244 			     PCI_ANY_ID, NULL);
245 	if (dev) {
246 		result = acpi_processor_errata_piix4(dev);
247 		pci_dev_put(dev);
248 	}
249 
250 	return result;
251 }
252 
253 /* --------------------------------------------------------------------------
254                               Common ACPI processor functions
255    -------------------------------------------------------------------------- */
256 
257 /*
258  * _PDC is required for a BIOS-OS handshake for most of the newer
259  * ACPI processor features.
260  */
261 static int acpi_processor_set_pdc(struct acpi_processor *pr)
262 {
263 	struct acpi_object_list *pdc_in = pr->pdc;
264 	acpi_status status = AE_OK;
265 
266 
267 	if (!pdc_in)
268 		return status;
269 
270 	status = acpi_evaluate_object(pr->handle, "_PDC", pdc_in, NULL);
271 
272 	if (ACPI_FAILURE(status))
273 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
274 		    "Could not evaluate _PDC, using legacy perf. control...\n"));
275 
276 	return status;
277 }
278 
279 /* --------------------------------------------------------------------------
280                               FS Interface (/proc)
281    -------------------------------------------------------------------------- */
282 
283 static struct proc_dir_entry *acpi_processor_dir = NULL;
284 
285 static int acpi_processor_info_seq_show(struct seq_file *seq, void *offset)
286 {
287 	struct acpi_processor *pr = seq->private;
288 
289 
290 	if (!pr)
291 		goto end;
292 
293 	seq_printf(seq, "processor id:            %d\n"
294 		   "acpi id:                 %d\n"
295 		   "bus mastering control:   %s\n"
296 		   "power management:        %s\n"
297 		   "throttling control:      %s\n"
298 		   "limit interface:         %s\n",
299 		   pr->id,
300 		   pr->acpi_id,
301 		   pr->flags.bm_control ? "yes" : "no",
302 		   pr->flags.power ? "yes" : "no",
303 		   pr->flags.throttling ? "yes" : "no",
304 		   pr->flags.limit ? "yes" : "no");
305 
306       end:
307 	return 0;
308 }
309 
310 static int acpi_processor_info_open_fs(struct inode *inode, struct file *file)
311 {
312 	return single_open(file, acpi_processor_info_seq_show,
313 			   PDE(inode)->data);
314 }
315 
316 static int acpi_processor_add_fs(struct acpi_device *device)
317 {
318 	struct proc_dir_entry *entry = NULL;
319 
320 
321 	if (!acpi_device_dir(device)) {
322 		acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
323 						     acpi_processor_dir);
324 		if (!acpi_device_dir(device))
325 			return -ENODEV;
326 	}
327 	acpi_device_dir(device)->owner = THIS_MODULE;
328 
329 	/* 'info' [R] */
330 	entry = proc_create_data(ACPI_PROCESSOR_FILE_INFO,
331 				 S_IRUGO, acpi_device_dir(device),
332 				 &acpi_processor_info_fops,
333 				 acpi_driver_data(device));
334 	if (!entry)
335 		return -EIO;
336 
337 	/* 'throttling' [R/W] */
338 	entry = proc_create_data(ACPI_PROCESSOR_FILE_THROTTLING,
339 				 S_IFREG | S_IRUGO | S_IWUSR,
340 				 acpi_device_dir(device),
341 				 &acpi_processor_throttling_fops,
342 				 acpi_driver_data(device));
343 	if (!entry)
344 		return -EIO;
345 
346 	/* 'limit' [R/W] */
347 	entry = proc_create_data(ACPI_PROCESSOR_FILE_LIMIT,
348 				 S_IFREG | S_IRUGO | S_IWUSR,
349 				 acpi_device_dir(device),
350 				 &acpi_processor_limit_fops,
351 				 acpi_driver_data(device));
352 	if (!entry)
353 		return -EIO;
354 	return 0;
355 }
356 
357 static int acpi_processor_remove_fs(struct acpi_device *device)
358 {
359 
360 	if (acpi_device_dir(device)) {
361 		remove_proc_entry(ACPI_PROCESSOR_FILE_INFO,
362 				  acpi_device_dir(device));
363 		remove_proc_entry(ACPI_PROCESSOR_FILE_THROTTLING,
364 				  acpi_device_dir(device));
365 		remove_proc_entry(ACPI_PROCESSOR_FILE_LIMIT,
366 				  acpi_device_dir(device));
367 		remove_proc_entry(acpi_device_bid(device), acpi_processor_dir);
368 		acpi_device_dir(device) = NULL;
369 	}
370 
371 	return 0;
372 }
373 
374 /* Use the acpiid in MADT to map cpus in case of SMP */
375 
376 #ifndef CONFIG_SMP
377 static int get_cpu_id(acpi_handle handle, u32 acpi_id) {return -1;}
378 #else
379 
380 static struct acpi_table_madt *madt;
381 
382 static int map_lapic_id(struct acpi_subtable_header *entry,
383 		 u32 acpi_id, int *apic_id)
384 {
385 	struct acpi_madt_local_apic *lapic =
386 		(struct acpi_madt_local_apic *)entry;
387 	if ((lapic->lapic_flags & ACPI_MADT_ENABLED) &&
388 	    lapic->processor_id == acpi_id) {
389 		*apic_id = lapic->id;
390 		return 1;
391 	}
392 	return 0;
393 }
394 
395 static int map_lsapic_id(struct acpi_subtable_header *entry,
396 		  u32 acpi_id, int *apic_id)
397 {
398 	struct acpi_madt_local_sapic *lsapic =
399 		(struct acpi_madt_local_sapic *)entry;
400 	/* Only check enabled APICs*/
401 	if (lsapic->lapic_flags & ACPI_MADT_ENABLED) {
402 		/* First check against id */
403 		if (lsapic->processor_id == acpi_id) {
404 			*apic_id = (lsapic->id << 8) | lsapic->eid;
405 			return 1;
406 		/* Check against optional uid */
407 		} else if (entry->length >= 16 &&
408 			lsapic->uid == acpi_id) {
409 			*apic_id = lsapic->uid;
410 			return 1;
411 		}
412 	}
413 	return 0;
414 }
415 
416 static int map_madt_entry(u32 acpi_id)
417 {
418 	unsigned long madt_end, entry;
419 	int apic_id = -1;
420 
421 	if (!madt)
422 		return apic_id;
423 
424 	entry = (unsigned long)madt;
425 	madt_end = entry + madt->header.length;
426 
427 	/* Parse all entries looking for a match. */
428 
429 	entry += sizeof(struct acpi_table_madt);
430 	while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
431 		struct acpi_subtable_header *header =
432 			(struct acpi_subtable_header *)entry;
433 		if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
434 			if (map_lapic_id(header, acpi_id, &apic_id))
435 				break;
436 		} else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
437 			if (map_lsapic_id(header, acpi_id, &apic_id))
438 				break;
439 		}
440 		entry += header->length;
441 	}
442 	return apic_id;
443 }
444 
445 static int map_mat_entry(acpi_handle handle, u32 acpi_id)
446 {
447 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
448 	union acpi_object *obj;
449 	struct acpi_subtable_header *header;
450 	int apic_id = -1;
451 
452 	if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
453 		goto exit;
454 
455 	if (!buffer.length || !buffer.pointer)
456 		goto exit;
457 
458 	obj = buffer.pointer;
459 	if (obj->type != ACPI_TYPE_BUFFER ||
460 	    obj->buffer.length < sizeof(struct acpi_subtable_header)) {
461 		goto exit;
462 	}
463 
464 	header = (struct acpi_subtable_header *)obj->buffer.pointer;
465 	if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
466 		map_lapic_id(header, acpi_id, &apic_id);
467 	} else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
468 		map_lsapic_id(header, acpi_id, &apic_id);
469 	}
470 
471 exit:
472 	if (buffer.pointer)
473 		kfree(buffer.pointer);
474 	return apic_id;
475 }
476 
477 static int get_cpu_id(acpi_handle handle, u32 acpi_id)
478 {
479 	int i;
480 	int apic_id = -1;
481 
482 	apic_id = map_mat_entry(handle, acpi_id);
483 	if (apic_id == -1)
484 		apic_id = map_madt_entry(acpi_id);
485 	if (apic_id == -1)
486 		return apic_id;
487 
488 	for_each_possible_cpu(i) {
489 		if (cpu_physical_id(i) == apic_id)
490 			return i;
491 	}
492 	return -1;
493 }
494 #endif
495 
496 /* --------------------------------------------------------------------------
497                                  Driver Interface
498    -------------------------------------------------------------------------- */
499 
500 static int acpi_processor_get_info(struct acpi_processor *pr, unsigned has_uid)
501 {
502 	acpi_status status = 0;
503 	union acpi_object object = { 0 };
504 	struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
505 	int cpu_index;
506 	static int cpu0_initialized;
507 
508 
509 	if (!pr)
510 		return -EINVAL;
511 
512 	if (num_online_cpus() > 1)
513 		errata.smp = TRUE;
514 
515 	acpi_processor_errata(pr);
516 
517 	/*
518 	 * Check to see if we have bus mastering arbitration control.  This
519 	 * is required for proper C3 usage (to maintain cache coherency).
520 	 */
521 	if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) {
522 		pr->flags.bm_control = 1;
523 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
524 				  "Bus mastering arbitration control present\n"));
525 	} else
526 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
527 				  "No bus mastering arbitration control\n"));
528 
529 	/* Check if it is a Device with HID and UID */
530 	if (has_uid) {
531 		unsigned long value;
532 		status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID,
533 						NULL, &value);
534 		if (ACPI_FAILURE(status)) {
535 			printk(KERN_ERR PREFIX "Evaluating processor _UID\n");
536 			return -ENODEV;
537 		}
538 		pr->acpi_id = value;
539 	} else {
540 		/*
541 		* Evalute the processor object.  Note that it is common on SMP to
542 		* have the first (boot) processor with a valid PBLK address while
543 		* all others have a NULL address.
544 		*/
545 		status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer);
546 		if (ACPI_FAILURE(status)) {
547 			printk(KERN_ERR PREFIX "Evaluating processor object\n");
548 			return -ENODEV;
549 		}
550 
551 		/*
552 		* TBD: Synch processor ID (via LAPIC/LSAPIC structures) on SMP.
553 		*      >>> 'acpi_get_processor_id(acpi_id, &id)' in arch/xxx/acpi.c
554 		*/
555 		pr->acpi_id = object.processor.proc_id;
556 	}
557 	cpu_index = get_cpu_id(pr->handle, pr->acpi_id);
558 
559 	/* Handle UP system running SMP kernel, with no LAPIC in MADT */
560 	if (!cpu0_initialized && (cpu_index == -1) &&
561 	    (num_online_cpus() == 1)) {
562 		cpu_index = 0;
563 	}
564 
565 	cpu0_initialized = 1;
566 
567 	pr->id = cpu_index;
568 
569 	/*
570 	 *  Extra Processor objects may be enumerated on MP systems with
571 	 *  less than the max # of CPUs. They should be ignored _iff
572 	 *  they are physically not present.
573 	 */
574 	if (pr->id == -1) {
575 		if (ACPI_FAILURE
576 		    (acpi_processor_hotadd_init(pr->handle, &pr->id))) {
577 			return -ENODEV;
578 		}
579 	}
580 
581 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id,
582 			  pr->acpi_id));
583 
584 	if (!object.processor.pblk_address)
585 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n"));
586 	else if (object.processor.pblk_length != 6)
587 		printk(KERN_ERR PREFIX "Invalid PBLK length [%d]\n",
588 			    object.processor.pblk_length);
589 	else {
590 		pr->throttling.address = object.processor.pblk_address;
591 		pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset;
592 		pr->throttling.duty_width = acpi_gbl_FADT.duty_width;
593 
594 		pr->pblk = object.processor.pblk_address;
595 
596 		/*
597 		 * We don't care about error returns - we just try to mark
598 		 * these reserved so that nobody else is confused into thinking
599 		 * that this region might be unused..
600 		 *
601 		 * (In particular, allocating the IO range for Cardbus)
602 		 */
603 		request_region(pr->throttling.address, 6, "ACPI CPU throttle");
604 	}
605 
606 	/*
607 	 * If ACPI describes a slot number for this CPU, we can use it
608 	 * ensure we get the right value in the "physical id" field
609 	 * of /proc/cpuinfo
610 	 */
611 	status = acpi_evaluate_object(pr->handle, "_SUN", NULL, &buffer);
612 	if (ACPI_SUCCESS(status))
613 		arch_fix_phys_package_id(pr->id, object.integer.value);
614 
615 	return 0;
616 }
617 
618 static void *processor_device_array[NR_CPUS];
619 
620 static int __cpuinit acpi_processor_start(struct acpi_device *device)
621 {
622 	int result = 0;
623 	acpi_status status = AE_OK;
624 	struct acpi_processor *pr;
625 
626 
627 	pr = acpi_driver_data(device);
628 
629 	result = acpi_processor_get_info(pr, device->flags.unique_id);
630 	if (result) {
631 		/* Processor is physically not present */
632 		return 0;
633 	}
634 
635 	BUG_ON((pr->id >= nr_cpu_ids) || (pr->id < 0));
636 
637 	/*
638 	 * Buggy BIOS check
639 	 * ACPI id of processors can be reported wrongly by the BIOS.
640 	 * Don't trust it blindly
641 	 */
642 	if (processor_device_array[pr->id] != NULL &&
643 	    processor_device_array[pr->id] != device) {
644 		printk(KERN_WARNING "BIOS reported wrong ACPI id "
645 			"for the processor\n");
646 		return -ENODEV;
647 	}
648 	processor_device_array[pr->id] = device;
649 
650 	processors[pr->id] = pr;
651 
652 	result = acpi_processor_add_fs(device);
653 	if (result)
654 		goto end;
655 
656 	status = acpi_install_notify_handler(pr->handle, ACPI_DEVICE_NOTIFY,
657 					     acpi_processor_notify, pr);
658 
659 	/* _PDC call should be done before doing anything else (if reqd.). */
660 	arch_acpi_processor_init_pdc(pr);
661 	acpi_processor_set_pdc(pr);
662 #ifdef CONFIG_CPU_FREQ
663 	acpi_processor_ppc_has_changed(pr);
664 #endif
665 	acpi_processor_get_throttling_info(pr);
666 	acpi_processor_get_limit_info(pr);
667 
668 
669 	acpi_processor_power_init(pr, device);
670 
671 	pr->cdev = thermal_cooling_device_register("Processor", device,
672 						&processor_cooling_ops);
673 	if (IS_ERR(pr->cdev)) {
674 		result = PTR_ERR(pr->cdev);
675 		goto end;
676 	}
677 	if (pr->cdev) {
678 		printk(KERN_INFO PREFIX
679 			"%s is registered as cooling_device%d\n",
680 			device->dev.bus_id, pr->cdev->id);
681 
682 		result = sysfs_create_link(&device->dev.kobj,
683 					   &pr->cdev->device.kobj,
684 					   "thermal_cooling");
685 		if (result)
686 			return result;
687 		result = sysfs_create_link(&pr->cdev->device.kobj,
688 					   &device->dev.kobj,
689 					   "device");
690 		if (result)
691 			return result;
692 	}
693 
694 	if (pr->flags.throttling) {
695 		printk(KERN_INFO PREFIX "%s [%s] (supports",
696 		       acpi_device_name(device), acpi_device_bid(device));
697 		printk(" %d throttling states", pr->throttling.state_count);
698 		printk(")\n");
699 	}
700 
701       end:
702 
703 	return result;
704 }
705 
706 static void acpi_processor_notify(acpi_handle handle, u32 event, void *data)
707 {
708 	struct acpi_processor *pr = data;
709 	struct acpi_device *device = NULL;
710 	int saved;
711 
712 	if (!pr)
713 		return;
714 
715 	if (acpi_bus_get_device(pr->handle, &device))
716 		return;
717 
718 	switch (event) {
719 	case ACPI_PROCESSOR_NOTIFY_PERFORMANCE:
720 		saved = pr->performance_platform_limit;
721 		acpi_processor_ppc_has_changed(pr);
722 		if (saved == pr->performance_platform_limit)
723 			break;
724 		acpi_bus_generate_proc_event(device, event,
725 					pr->performance_platform_limit);
726 		acpi_bus_generate_netlink_event(device->pnp.device_class,
727 						  device->dev.bus_id, event,
728 						  pr->performance_platform_limit);
729 		break;
730 	case ACPI_PROCESSOR_NOTIFY_POWER:
731 		acpi_processor_cst_has_changed(pr);
732 		acpi_bus_generate_proc_event(device, event, 0);
733 		acpi_bus_generate_netlink_event(device->pnp.device_class,
734 						  device->dev.bus_id, event, 0);
735 		break;
736 	case ACPI_PROCESSOR_NOTIFY_THROTTLING:
737 		acpi_processor_tstate_has_changed(pr);
738 		acpi_bus_generate_proc_event(device, event, 0);
739 		acpi_bus_generate_netlink_event(device->pnp.device_class,
740 						  device->dev.bus_id, event, 0);
741 	default:
742 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
743 				  "Unsupported event [0x%x]\n", event));
744 		break;
745 	}
746 
747 	return;
748 }
749 
750 static int acpi_cpu_soft_notify(struct notifier_block *nfb,
751 		unsigned long action, void *hcpu)
752 {
753 	unsigned int cpu = (unsigned long)hcpu;
754 	struct acpi_processor *pr = processors[cpu];
755 
756 	if (action == CPU_ONLINE && pr) {
757 		acpi_processor_ppc_has_changed(pr);
758 		acpi_processor_cst_has_changed(pr);
759 		acpi_processor_tstate_has_changed(pr);
760 	}
761 	return NOTIFY_OK;
762 }
763 
764 static struct notifier_block acpi_cpu_notifier =
765 {
766 	    .notifier_call = acpi_cpu_soft_notify,
767 };
768 
769 static int acpi_processor_add(struct acpi_device *device)
770 {
771 	struct acpi_processor *pr = NULL;
772 
773 
774 	if (!device)
775 		return -EINVAL;
776 
777 	pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
778 	if (!pr)
779 		return -ENOMEM;
780 
781 	pr->handle = device->handle;
782 	strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
783 	strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
784 	acpi_driver_data(device) = pr;
785 
786 	return 0;
787 }
788 
789 static int acpi_processor_remove(struct acpi_device *device, int type)
790 {
791 	acpi_status status = AE_OK;
792 	struct acpi_processor *pr = NULL;
793 
794 
795 	if (!device || !acpi_driver_data(device))
796 		return -EINVAL;
797 
798 	pr = acpi_driver_data(device);
799 
800 	if (pr->id >= nr_cpu_ids) {
801 		kfree(pr);
802 		return 0;
803 	}
804 
805 	if (type == ACPI_BUS_REMOVAL_EJECT) {
806 		if (acpi_processor_handle_eject(pr))
807 			return -EINVAL;
808 	}
809 
810 	acpi_processor_power_exit(pr, device);
811 
812 	status = acpi_remove_notify_handler(pr->handle, ACPI_DEVICE_NOTIFY,
813 					    acpi_processor_notify);
814 
815 	acpi_processor_remove_fs(device);
816 
817 	if (pr->cdev) {
818 		sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
819 		sysfs_remove_link(&pr->cdev->device.kobj, "device");
820 		thermal_cooling_device_unregister(pr->cdev);
821 		pr->cdev = NULL;
822 	}
823 
824 	processors[pr->id] = NULL;
825 	processor_device_array[pr->id] = NULL;
826 	kfree(pr);
827 
828 	return 0;
829 }
830 
831 #ifdef CONFIG_ACPI_HOTPLUG_CPU
832 /****************************************************************************
833  * 	Acpi processor hotplug support 				       	    *
834  ****************************************************************************/
835 
836 static int is_processor_present(acpi_handle handle)
837 {
838 	acpi_status status;
839 	unsigned long sta = 0;
840 
841 
842 	status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
843 
844 	if (ACPI_SUCCESS(status) && (sta & ACPI_STA_DEVICE_PRESENT))
845 		return 1;
846 
847 	/*
848 	 * _STA is mandatory for a processor that supports hot plug
849 	 */
850 	if (status == AE_NOT_FOUND)
851 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
852 				"Processor does not support hot plug\n"));
853 	else
854 		ACPI_EXCEPTION((AE_INFO, status,
855 				"Processor Device is not present"));
856 	return 0;
857 }
858 
859 static
860 int acpi_processor_device_add(acpi_handle handle, struct acpi_device **device)
861 {
862 	acpi_handle phandle;
863 	struct acpi_device *pdev;
864 	struct acpi_processor *pr;
865 
866 
867 	if (acpi_get_parent(handle, &phandle)) {
868 		return -ENODEV;
869 	}
870 
871 	if (acpi_bus_get_device(phandle, &pdev)) {
872 		return -ENODEV;
873 	}
874 
875 	if (acpi_bus_add(device, pdev, handle, ACPI_BUS_TYPE_PROCESSOR)) {
876 		return -ENODEV;
877 	}
878 
879 	acpi_bus_start(*device);
880 
881 	pr = acpi_driver_data(*device);
882 	if (!pr)
883 		return -ENODEV;
884 
885 	if ((pr->id >= 0) && (pr->id < nr_cpu_ids)) {
886 		kobject_uevent(&(*device)->dev.kobj, KOBJ_ONLINE);
887 	}
888 	return 0;
889 }
890 
891 static void __ref acpi_processor_hotplug_notify(acpi_handle handle,
892 						u32 event, void *data)
893 {
894 	struct acpi_processor *pr;
895 	struct acpi_device *device = NULL;
896 	int result;
897 
898 
899 	switch (event) {
900 	case ACPI_NOTIFY_BUS_CHECK:
901 	case ACPI_NOTIFY_DEVICE_CHECK:
902 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
903 		"Processor driver received %s event\n",
904 		       (event == ACPI_NOTIFY_BUS_CHECK) ?
905 		       "ACPI_NOTIFY_BUS_CHECK" : "ACPI_NOTIFY_DEVICE_CHECK"));
906 
907 		if (!is_processor_present(handle))
908 			break;
909 
910 		if (acpi_bus_get_device(handle, &device)) {
911 			result = acpi_processor_device_add(handle, &device);
912 			if (result)
913 				printk(KERN_ERR PREFIX
914 					    "Unable to add the device\n");
915 			break;
916 		}
917 
918 		pr = acpi_driver_data(device);
919 		if (!pr) {
920 			printk(KERN_ERR PREFIX "Driver data is NULL\n");
921 			break;
922 		}
923 
924 		if (pr->id >= 0 && (pr->id < nr_cpu_ids)) {
925 			kobject_uevent(&device->dev.kobj, KOBJ_OFFLINE);
926 			break;
927 		}
928 
929 		result = acpi_processor_start(device);
930 		if ((!result) && ((pr->id >= 0) && (pr->id < nr_cpu_ids))) {
931 			kobject_uevent(&device->dev.kobj, KOBJ_ONLINE);
932 		} else {
933 			printk(KERN_ERR PREFIX "Device [%s] failed to start\n",
934 				    acpi_device_bid(device));
935 		}
936 		break;
937 	case ACPI_NOTIFY_EJECT_REQUEST:
938 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
939 				  "received ACPI_NOTIFY_EJECT_REQUEST\n"));
940 
941 		if (acpi_bus_get_device(handle, &device)) {
942 			printk(KERN_ERR PREFIX
943 				    "Device don't exist, dropping EJECT\n");
944 			break;
945 		}
946 		pr = acpi_driver_data(device);
947 		if (!pr) {
948 			printk(KERN_ERR PREFIX
949 				    "Driver data is NULL, dropping EJECT\n");
950 			return;
951 		}
952 
953 		if ((pr->id < nr_cpu_ids) && (cpu_present(pr->id)))
954 			kobject_uevent(&device->dev.kobj, KOBJ_OFFLINE);
955 		break;
956 	default:
957 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
958 				  "Unsupported event [0x%x]\n", event));
959 		break;
960 	}
961 
962 	return;
963 }
964 
965 static acpi_status
966 processor_walk_namespace_cb(acpi_handle handle,
967 			    u32 lvl, void *context, void **rv)
968 {
969 	acpi_status status;
970 	int *action = context;
971 	acpi_object_type type = 0;
972 
973 	status = acpi_get_type(handle, &type);
974 	if (ACPI_FAILURE(status))
975 		return (AE_OK);
976 
977 	if (type != ACPI_TYPE_PROCESSOR)
978 		return (AE_OK);
979 
980 	switch (*action) {
981 	case INSTALL_NOTIFY_HANDLER:
982 		acpi_install_notify_handler(handle,
983 					    ACPI_SYSTEM_NOTIFY,
984 					    acpi_processor_hotplug_notify,
985 					    NULL);
986 		break;
987 	case UNINSTALL_NOTIFY_HANDLER:
988 		acpi_remove_notify_handler(handle,
989 					   ACPI_SYSTEM_NOTIFY,
990 					   acpi_processor_hotplug_notify);
991 		break;
992 	default:
993 		break;
994 	}
995 
996 	return (AE_OK);
997 }
998 
999 static acpi_status acpi_processor_hotadd_init(acpi_handle handle, int *p_cpu)
1000 {
1001 
1002 	if (!is_processor_present(handle)) {
1003 		return AE_ERROR;
1004 	}
1005 
1006 	if (acpi_map_lsapic(handle, p_cpu))
1007 		return AE_ERROR;
1008 
1009 	if (arch_register_cpu(*p_cpu)) {
1010 		acpi_unmap_lsapic(*p_cpu);
1011 		return AE_ERROR;
1012 	}
1013 
1014 	return AE_OK;
1015 }
1016 
1017 static int acpi_processor_handle_eject(struct acpi_processor *pr)
1018 {
1019 	if (cpu_online(pr->id)) {
1020 		return (-EINVAL);
1021 	}
1022 	arch_unregister_cpu(pr->id);
1023 	acpi_unmap_lsapic(pr->id);
1024 	return (0);
1025 }
1026 #else
1027 static acpi_status acpi_processor_hotadd_init(acpi_handle handle, int *p_cpu)
1028 {
1029 	return AE_ERROR;
1030 }
1031 static int acpi_processor_handle_eject(struct acpi_processor *pr)
1032 {
1033 	return (-EINVAL);
1034 }
1035 #endif
1036 
1037 static
1038 void acpi_processor_install_hotplug_notify(void)
1039 {
1040 #ifdef CONFIG_ACPI_HOTPLUG_CPU
1041 	int action = INSTALL_NOTIFY_HANDLER;
1042 	acpi_walk_namespace(ACPI_TYPE_PROCESSOR,
1043 			    ACPI_ROOT_OBJECT,
1044 			    ACPI_UINT32_MAX,
1045 			    processor_walk_namespace_cb, &action, NULL);
1046 #endif
1047 	register_hotcpu_notifier(&acpi_cpu_notifier);
1048 }
1049 
1050 static
1051 void acpi_processor_uninstall_hotplug_notify(void)
1052 {
1053 #ifdef CONFIG_ACPI_HOTPLUG_CPU
1054 	int action = UNINSTALL_NOTIFY_HANDLER;
1055 	acpi_walk_namespace(ACPI_TYPE_PROCESSOR,
1056 			    ACPI_ROOT_OBJECT,
1057 			    ACPI_UINT32_MAX,
1058 			    processor_walk_namespace_cb, &action, NULL);
1059 #endif
1060 	unregister_hotcpu_notifier(&acpi_cpu_notifier);
1061 }
1062 
1063 /*
1064  * We keep the driver loaded even when ACPI is not running.
1065  * This is needed for the powernow-k8 driver, that works even without
1066  * ACPI, but needs symbols from this driver
1067  */
1068 
1069 static int __init acpi_processor_init(void)
1070 {
1071 	int result = 0;
1072 
1073 
1074 	memset(&processors, 0, sizeof(processors));
1075 	memset(&errata, 0, sizeof(errata));
1076 
1077 #ifdef CONFIG_SMP
1078 	if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0,
1079 				(struct acpi_table_header **)&madt)))
1080 		madt = NULL;
1081 #endif
1082 
1083 	acpi_processor_dir = proc_mkdir(ACPI_PROCESSOR_CLASS, acpi_root_dir);
1084 	if (!acpi_processor_dir)
1085 		return -ENOMEM;
1086 	acpi_processor_dir->owner = THIS_MODULE;
1087 
1088 	result = cpuidle_register_driver(&acpi_idle_driver);
1089 	if (result < 0)
1090 		goto out_proc;
1091 
1092 	result = acpi_bus_register_driver(&acpi_processor_driver);
1093 	if (result < 0)
1094 		goto out_cpuidle;
1095 
1096 	acpi_processor_install_hotplug_notify();
1097 
1098 	acpi_thermal_cpufreq_init();
1099 
1100 	acpi_processor_ppc_init();
1101 
1102 	acpi_processor_throttling_init();
1103 
1104 	return 0;
1105 
1106 out_cpuidle:
1107 	cpuidle_unregister_driver(&acpi_idle_driver);
1108 
1109 out_proc:
1110 	remove_proc_entry(ACPI_PROCESSOR_CLASS, acpi_root_dir);
1111 
1112 	return result;
1113 }
1114 
1115 static void __exit acpi_processor_exit(void)
1116 {
1117 	acpi_processor_ppc_exit();
1118 
1119 	acpi_thermal_cpufreq_exit();
1120 
1121 	acpi_processor_uninstall_hotplug_notify();
1122 
1123 	acpi_bus_unregister_driver(&acpi_processor_driver);
1124 
1125 	cpuidle_unregister_driver(&acpi_idle_driver);
1126 
1127 	remove_proc_entry(ACPI_PROCESSOR_CLASS, acpi_root_dir);
1128 
1129 	return;
1130 }
1131 
1132 module_init(acpi_processor_init);
1133 module_exit(acpi_processor_exit);
1134 
1135 EXPORT_SYMBOL(acpi_processor_set_thermal_limit);
1136 
1137 MODULE_ALIAS("processor");
1138