xref: /linux/drivers/acpi/processor_core.c (revision d8327c784b51b57dac2c26cfad87dce0d68dfd98)
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 
48 #include <asm/io.h>
49 #include <asm/system.h>
50 #include <asm/cpu.h>
51 #include <asm/delay.h>
52 #include <asm/uaccess.h>
53 #include <asm/processor.h>
54 #include <asm/smp.h>
55 #include <asm/acpi.h>
56 
57 #include <acpi/acpi_bus.h>
58 #include <acpi/acpi_drivers.h>
59 #include <acpi/processor.h>
60 
61 #define ACPI_PROCESSOR_COMPONENT	0x01000000
62 #define ACPI_PROCESSOR_CLASS		"processor"
63 #define ACPI_PROCESSOR_DRIVER_NAME	"ACPI Processor Driver"
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 
71 #define ACPI_PROCESSOR_LIMIT_USER	0
72 #define ACPI_PROCESSOR_LIMIT_THERMAL	1
73 
74 #define ACPI_STA_PRESENT 0x00000001
75 
76 #define _COMPONENT		ACPI_PROCESSOR_COMPONENT
77 ACPI_MODULE_NAME("acpi_processor")
78 
79     MODULE_AUTHOR("Paul Diefenbaugh");
80 MODULE_DESCRIPTION(ACPI_PROCESSOR_DRIVER_NAME);
81 MODULE_LICENSE("GPL");
82 
83 static int acpi_processor_add(struct acpi_device *device);
84 static int acpi_processor_start(struct acpi_device *device);
85 static int acpi_processor_remove(struct acpi_device *device, int type);
86 static int acpi_processor_info_open_fs(struct inode *inode, struct file *file);
87 static void acpi_processor_notify(acpi_handle handle, u32 event, void *data);
88 static acpi_status acpi_processor_hotadd_init(acpi_handle handle, int *p_cpu);
89 static int acpi_processor_handle_eject(struct acpi_processor *pr);
90 
91 static struct acpi_driver acpi_processor_driver = {
92 	.name = ACPI_PROCESSOR_DRIVER_NAME,
93 	.class = ACPI_PROCESSOR_CLASS,
94 	.ids = ACPI_PROCESSOR_HID,
95 	.ops = {
96 		.add = acpi_processor_add,
97 		.remove = acpi_processor_remove,
98 		.start = acpi_processor_start,
99 		},
100 };
101 
102 #define INSTALL_NOTIFY_HANDLER		1
103 #define UNINSTALL_NOTIFY_HANDLER	2
104 
105 static struct file_operations acpi_processor_info_fops = {
106 	.open = acpi_processor_info_open_fs,
107 	.read = seq_read,
108 	.llseek = seq_lseek,
109 	.release = single_release,
110 };
111 
112 struct acpi_processor *processors[NR_CPUS];
113 struct acpi_processor_errata errata;
114 
115 /* --------------------------------------------------------------------------
116                                 Errata Handling
117    -------------------------------------------------------------------------- */
118 
119 static int acpi_processor_errata_piix4(struct pci_dev *dev)
120 {
121 	u8 rev = 0;
122 	u8 value1 = 0;
123 	u8 value2 = 0;
124 
125 	ACPI_FUNCTION_TRACE("acpi_processor_errata_piix4");
126 
127 	if (!dev)
128 		return_VALUE(-EINVAL);
129 
130 	/*
131 	 * Note that 'dev' references the PIIX4 ACPI Controller.
132 	 */
133 
134 	pci_read_config_byte(dev, PCI_REVISION_ID, &rev);
135 
136 	switch (rev) {
137 	case 0:
138 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 A-step\n"));
139 		break;
140 	case 1:
141 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 B-step\n"));
142 		break;
143 	case 2:
144 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4E\n"));
145 		break;
146 	case 3:
147 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4M\n"));
148 		break;
149 	default:
150 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found unknown PIIX4\n"));
151 		break;
152 	}
153 
154 	switch (rev) {
155 
156 	case 0:		/* PIIX4 A-step */
157 	case 1:		/* PIIX4 B-step */
158 		/*
159 		 * See specification changes #13 ("Manual Throttle Duty Cycle")
160 		 * and #14 ("Enabling and Disabling Manual Throttle"), plus
161 		 * erratum #5 ("STPCLK# Deassertion Time") from the January
162 		 * 2002 PIIX4 specification update.  Applies to only older
163 		 * PIIX4 models.
164 		 */
165 		errata.piix4.throttle = 1;
166 
167 	case 2:		/* PIIX4E */
168 	case 3:		/* PIIX4M */
169 		/*
170 		 * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA
171 		 * Livelock") from the January 2002 PIIX4 specification update.
172 		 * Applies to all PIIX4 models.
173 		 */
174 
175 		/*
176 		 * BM-IDE
177 		 * ------
178 		 * Find the PIIX4 IDE Controller and get the Bus Master IDE
179 		 * Status register address.  We'll use this later to read
180 		 * each IDE controller's DMA status to make sure we catch all
181 		 * DMA activity.
182 		 */
183 		dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
184 				     PCI_DEVICE_ID_INTEL_82371AB,
185 				     PCI_ANY_ID, PCI_ANY_ID, NULL);
186 		if (dev) {
187 			errata.piix4.bmisx = pci_resource_start(dev, 4);
188 			pci_dev_put(dev);
189 		}
190 
191 		/*
192 		 * Type-F DMA
193 		 * ----------
194 		 * Find the PIIX4 ISA Controller and read the Motherboard
195 		 * DMA controller's status to see if Type-F (Fast) DMA mode
196 		 * is enabled (bit 7) on either channel.  Note that we'll
197 		 * disable C3 support if this is enabled, as some legacy
198 		 * devices won't operate well if fast DMA is disabled.
199 		 */
200 		dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
201 				     PCI_DEVICE_ID_INTEL_82371AB_0,
202 				     PCI_ANY_ID, PCI_ANY_ID, NULL);
203 		if (dev) {
204 			pci_read_config_byte(dev, 0x76, &value1);
205 			pci_read_config_byte(dev, 0x77, &value2);
206 			if ((value1 & 0x80) || (value2 & 0x80))
207 				errata.piix4.fdma = 1;
208 			pci_dev_put(dev);
209 		}
210 
211 		break;
212 	}
213 
214 	if (errata.piix4.bmisx)
215 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
216 				  "Bus master activity detection (BM-IDE) erratum enabled\n"));
217 	if (errata.piix4.fdma)
218 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
219 				  "Type-F DMA livelock erratum (C3 disabled)\n"));
220 
221 	return_VALUE(0);
222 }
223 
224 static int acpi_processor_errata(struct acpi_processor *pr)
225 {
226 	int result = 0;
227 	struct pci_dev *dev = NULL;
228 
229 	ACPI_FUNCTION_TRACE("acpi_processor_errata");
230 
231 	if (!pr)
232 		return_VALUE(-EINVAL);
233 
234 	/*
235 	 * PIIX4
236 	 */
237 	dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
238 			     PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID,
239 			     PCI_ANY_ID, NULL);
240 	if (dev) {
241 		result = acpi_processor_errata_piix4(dev);
242 		pci_dev_put(dev);
243 	}
244 
245 	return_VALUE(result);
246 }
247 
248 /* --------------------------------------------------------------------------
249                               Common ACPI processor fucntions
250    -------------------------------------------------------------------------- */
251 
252 /*
253  * _PDC is required for a BIOS-OS handshake for most of the newer
254  * ACPI processor features.
255  */
256 static int acpi_processor_set_pdc(struct acpi_processor *pr)
257 {
258 	struct acpi_object_list *pdc_in = pr->pdc;
259 	acpi_status status = AE_OK;
260 
261 	ACPI_FUNCTION_TRACE("acpi_processor_set_pdc");
262 
263 	if (!pdc_in)
264 		return_VALUE(status);
265 
266 	status = acpi_evaluate_object(pr->handle, "_PDC", pdc_in, NULL);
267 
268 	if (ACPI_FAILURE(status))
269 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
270 		    "Could not evaluate _PDC, using legacy perf. control...\n"));
271 
272 	return_VALUE(status);
273 }
274 
275 /* --------------------------------------------------------------------------
276                               FS Interface (/proc)
277    -------------------------------------------------------------------------- */
278 
279 static struct proc_dir_entry *acpi_processor_dir = NULL;
280 
281 static int acpi_processor_info_seq_show(struct seq_file *seq, void *offset)
282 {
283 	struct acpi_processor *pr = (struct acpi_processor *)seq->private;
284 
285 	ACPI_FUNCTION_TRACE("acpi_processor_info_seq_show");
286 
287 	if (!pr)
288 		goto end;
289 
290 	seq_printf(seq, "processor id:            %d\n"
291 		   "acpi id:                 %d\n"
292 		   "bus mastering control:   %s\n"
293 		   "power management:        %s\n"
294 		   "throttling control:      %s\n"
295 		   "limit interface:         %s\n",
296 		   pr->id,
297 		   pr->acpi_id,
298 		   pr->flags.bm_control ? "yes" : "no",
299 		   pr->flags.power ? "yes" : "no",
300 		   pr->flags.throttling ? "yes" : "no",
301 		   pr->flags.limit ? "yes" : "no");
302 
303       end:
304 	return_VALUE(0);
305 }
306 
307 static int acpi_processor_info_open_fs(struct inode *inode, struct file *file)
308 {
309 	return single_open(file, acpi_processor_info_seq_show,
310 			   PDE(inode)->data);
311 }
312 
313 static int acpi_processor_add_fs(struct acpi_device *device)
314 {
315 	struct proc_dir_entry *entry = NULL;
316 
317 	ACPI_FUNCTION_TRACE("acpi_processor_add_fs");
318 
319 	if (!acpi_device_dir(device)) {
320 		acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
321 						     acpi_processor_dir);
322 		if (!acpi_device_dir(device))
323 			return_VALUE(-ENODEV);
324 	}
325 	acpi_device_dir(device)->owner = THIS_MODULE;
326 
327 	/* 'info' [R] */
328 	entry = create_proc_entry(ACPI_PROCESSOR_FILE_INFO,
329 				  S_IRUGO, acpi_device_dir(device));
330 	if (!entry)
331 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
332 				  "Unable to create '%s' fs entry\n",
333 				  ACPI_PROCESSOR_FILE_INFO));
334 	else {
335 		entry->proc_fops = &acpi_processor_info_fops;
336 		entry->data = acpi_driver_data(device);
337 		entry->owner = THIS_MODULE;
338 	}
339 
340 	/* 'throttling' [R/W] */
341 	entry = create_proc_entry(ACPI_PROCESSOR_FILE_THROTTLING,
342 				  S_IFREG | S_IRUGO | S_IWUSR,
343 				  acpi_device_dir(device));
344 	if (!entry)
345 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
346 				  "Unable to create '%s' fs entry\n",
347 				  ACPI_PROCESSOR_FILE_THROTTLING));
348 	else {
349 		entry->proc_fops = &acpi_processor_throttling_fops;
350 		entry->data = acpi_driver_data(device);
351 		entry->owner = THIS_MODULE;
352 	}
353 
354 	/* 'limit' [R/W] */
355 	entry = create_proc_entry(ACPI_PROCESSOR_FILE_LIMIT,
356 				  S_IFREG | S_IRUGO | S_IWUSR,
357 				  acpi_device_dir(device));
358 	if (!entry)
359 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
360 				  "Unable to create '%s' fs entry\n",
361 				  ACPI_PROCESSOR_FILE_LIMIT));
362 	else {
363 		entry->proc_fops = &acpi_processor_limit_fops;
364 		entry->data = acpi_driver_data(device);
365 		entry->owner = THIS_MODULE;
366 	}
367 
368 	return_VALUE(0);
369 }
370 
371 static int acpi_processor_remove_fs(struct acpi_device *device)
372 {
373 	ACPI_FUNCTION_TRACE("acpi_processor_remove_fs");
374 
375 	if (acpi_device_dir(device)) {
376 		remove_proc_entry(ACPI_PROCESSOR_FILE_INFO,
377 				  acpi_device_dir(device));
378 		remove_proc_entry(ACPI_PROCESSOR_FILE_THROTTLING,
379 				  acpi_device_dir(device));
380 		remove_proc_entry(ACPI_PROCESSOR_FILE_LIMIT,
381 				  acpi_device_dir(device));
382 		remove_proc_entry(acpi_device_bid(device), acpi_processor_dir);
383 		acpi_device_dir(device) = NULL;
384 	}
385 
386 	return_VALUE(0);
387 }
388 
389 /* Use the acpiid in MADT to map cpus in case of SMP */
390 #ifndef CONFIG_SMP
391 #define convert_acpiid_to_cpu(acpi_id) (0xff)
392 #else
393 
394 #ifdef CONFIG_IA64
395 #define arch_acpiid_to_apicid 	ia64_acpiid_to_sapicid
396 #define arch_cpu_to_apicid 	ia64_cpu_to_sapicid
397 #define ARCH_BAD_APICID		(0xffff)
398 #else
399 #define arch_acpiid_to_apicid 	x86_acpiid_to_apicid
400 #define arch_cpu_to_apicid 	x86_cpu_to_apicid
401 #define ARCH_BAD_APICID		(0xff)
402 #endif
403 
404 static u8 convert_acpiid_to_cpu(u8 acpi_id)
405 {
406 	u16 apic_id;
407 	int i;
408 
409 	apic_id = arch_acpiid_to_apicid[acpi_id];
410 	if (apic_id == ARCH_BAD_APICID)
411 		return -1;
412 
413 	for (i = 0; i < NR_CPUS; i++) {
414 		if (arch_cpu_to_apicid[i] == apic_id)
415 			return i;
416 	}
417 	return -1;
418 }
419 #endif
420 
421 /* --------------------------------------------------------------------------
422                                  Driver Interface
423    -------------------------------------------------------------------------- */
424 
425 static int acpi_processor_get_info(struct acpi_processor *pr)
426 {
427 	acpi_status status = 0;
428 	union acpi_object object = { 0 };
429 	struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
430 	u8 cpu_index;
431 	static int cpu0_initialized;
432 
433 	ACPI_FUNCTION_TRACE("acpi_processor_get_info");
434 
435 	if (!pr)
436 		return_VALUE(-EINVAL);
437 
438 	if (num_online_cpus() > 1)
439 		errata.smp = TRUE;
440 
441 	acpi_processor_errata(pr);
442 
443 	/*
444 	 * Check to see if we have bus mastering arbitration control.  This
445 	 * is required for proper C3 usage (to maintain cache coherency).
446 	 */
447 	if (acpi_fadt.V1_pm2_cnt_blk && acpi_fadt.pm2_cnt_len) {
448 		pr->flags.bm_control = 1;
449 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
450 				  "Bus mastering arbitration control present\n"));
451 	} else
452 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
453 				  "No bus mastering arbitration control\n"));
454 
455 	/*
456 	 * Evalute the processor object.  Note that it is common on SMP to
457 	 * have the first (boot) processor with a valid PBLK address while
458 	 * all others have a NULL address.
459 	 */
460 	status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer);
461 	if (ACPI_FAILURE(status)) {
462 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
463 				  "Error evaluating processor object\n"));
464 		return_VALUE(-ENODEV);
465 	}
466 
467 	/*
468 	 * TBD: Synch processor ID (via LAPIC/LSAPIC structures) on SMP.
469 	 *      >>> 'acpi_get_processor_id(acpi_id, &id)' in arch/xxx/acpi.c
470 	 */
471 	pr->acpi_id = object.processor.proc_id;
472 
473 	cpu_index = convert_acpiid_to_cpu(pr->acpi_id);
474 
475 	/* Handle UP system running SMP kernel, with no LAPIC in MADT */
476 	if (!cpu0_initialized && (cpu_index == 0xff) &&
477 	    (num_online_cpus() == 1)) {
478 		cpu_index = 0;
479 	}
480 
481 	cpu0_initialized = 1;
482 
483 	pr->id = cpu_index;
484 
485 	/*
486 	 *  Extra Processor objects may be enumerated on MP systems with
487 	 *  less than the max # of CPUs. They should be ignored _iff
488 	 *  they are physically not present.
489 	 */
490 	if (cpu_index >= NR_CPUS) {
491 		if (ACPI_FAILURE
492 		    (acpi_processor_hotadd_init(pr->handle, &pr->id))) {
493 			ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
494 					  "Error getting cpuindex for acpiid 0x%x\n",
495 					  pr->acpi_id));
496 			return_VALUE(-ENODEV);
497 		}
498 	}
499 
500 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id,
501 			  pr->acpi_id));
502 
503 	if (!object.processor.pblk_address)
504 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n"));
505 	else if (object.processor.pblk_length != 6)
506 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid PBLK length [%d]\n",
507 				  object.processor.pblk_length));
508 	else {
509 		pr->throttling.address = object.processor.pblk_address;
510 		pr->throttling.duty_offset = acpi_fadt.duty_offset;
511 		pr->throttling.duty_width = acpi_fadt.duty_width;
512 
513 		pr->pblk = object.processor.pblk_address;
514 
515 		/*
516 		 * We don't care about error returns - we just try to mark
517 		 * these reserved so that nobody else is confused into thinking
518 		 * that this region might be unused..
519 		 *
520 		 * (In particular, allocating the IO range for Cardbus)
521 		 */
522 		request_region(pr->throttling.address, 6, "ACPI CPU throttle");
523 	}
524 
525 #ifdef CONFIG_CPU_FREQ
526 	acpi_processor_ppc_has_changed(pr);
527 #endif
528 	acpi_processor_get_throttling_info(pr);
529 	acpi_processor_get_limit_info(pr);
530 
531 	return_VALUE(0);
532 }
533 
534 static void *processor_device_array[NR_CPUS];
535 
536 static int acpi_processor_start(struct acpi_device *device)
537 {
538 	int result = 0;
539 	acpi_status status = AE_OK;
540 	struct acpi_processor *pr;
541 
542 	ACPI_FUNCTION_TRACE("acpi_processor_start");
543 
544 	pr = acpi_driver_data(device);
545 
546 	result = acpi_processor_get_info(pr);
547 	if (result) {
548 		/* Processor is physically not present */
549 		return_VALUE(0);
550 	}
551 
552 	BUG_ON((pr->id >= NR_CPUS) || (pr->id < 0));
553 
554 	/*
555 	 * Buggy BIOS check
556 	 * ACPI id of processors can be reported wrongly by the BIOS.
557 	 * Don't trust it blindly
558 	 */
559 	if (processor_device_array[pr->id] != NULL &&
560 	    processor_device_array[pr->id] != (void *)device) {
561 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "BIOS reporting wrong ACPI id"
562 			"for the processor\n"));
563 		return_VALUE(-ENODEV);
564 	}
565 	processor_device_array[pr->id] = (void *)device;
566 
567 	processors[pr->id] = pr;
568 
569 	result = acpi_processor_add_fs(device);
570 	if (result)
571 		goto end;
572 
573 	status = acpi_install_notify_handler(pr->handle, ACPI_DEVICE_NOTIFY,
574 					     acpi_processor_notify, pr);
575 	if (ACPI_FAILURE(status)) {
576 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
577 				  "Error installing device notify handler\n"));
578 	}
579 
580 	/* _PDC call should be done before doing anything else (if reqd.). */
581 	arch_acpi_processor_init_pdc(pr);
582 	acpi_processor_set_pdc(pr);
583 
584 	acpi_processor_power_init(pr, device);
585 
586 	if (pr->flags.throttling) {
587 		printk(KERN_INFO PREFIX "%s [%s] (supports",
588 		       acpi_device_name(device), acpi_device_bid(device));
589 		printk(" %d throttling states", pr->throttling.state_count);
590 		printk(")\n");
591 	}
592 
593       end:
594 
595 	return_VALUE(result);
596 }
597 
598 static void acpi_processor_notify(acpi_handle handle, u32 event, void *data)
599 {
600 	struct acpi_processor *pr = (struct acpi_processor *)data;
601 	struct acpi_device *device = NULL;
602 
603 	ACPI_FUNCTION_TRACE("acpi_processor_notify");
604 
605 	if (!pr)
606 		return_VOID;
607 
608 	if (acpi_bus_get_device(pr->handle, &device))
609 		return_VOID;
610 
611 	switch (event) {
612 	case ACPI_PROCESSOR_NOTIFY_PERFORMANCE:
613 		acpi_processor_ppc_has_changed(pr);
614 		acpi_bus_generate_event(device, event,
615 					pr->performance_platform_limit);
616 		break;
617 	case ACPI_PROCESSOR_NOTIFY_POWER:
618 		acpi_processor_cst_has_changed(pr);
619 		acpi_bus_generate_event(device, event, 0);
620 		break;
621 	default:
622 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
623 				  "Unsupported event [0x%x]\n", event));
624 		break;
625 	}
626 
627 	return_VOID;
628 }
629 
630 static int acpi_processor_add(struct acpi_device *device)
631 {
632 	struct acpi_processor *pr = NULL;
633 
634 	ACPI_FUNCTION_TRACE("acpi_processor_add");
635 
636 	if (!device)
637 		return_VALUE(-EINVAL);
638 
639 	pr = kmalloc(sizeof(struct acpi_processor), GFP_KERNEL);
640 	if (!pr)
641 		return_VALUE(-ENOMEM);
642 	memset(pr, 0, sizeof(struct acpi_processor));
643 
644 	pr->handle = device->handle;
645 	strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
646 	strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
647 	acpi_driver_data(device) = pr;
648 
649 	return_VALUE(0);
650 }
651 
652 static int acpi_processor_remove(struct acpi_device *device, int type)
653 {
654 	acpi_status status = AE_OK;
655 	struct acpi_processor *pr = NULL;
656 
657 	ACPI_FUNCTION_TRACE("acpi_processor_remove");
658 
659 	if (!device || !acpi_driver_data(device))
660 		return_VALUE(-EINVAL);
661 
662 	pr = (struct acpi_processor *)acpi_driver_data(device);
663 
664 	if (pr->id >= NR_CPUS) {
665 		kfree(pr);
666 		return_VALUE(0);
667 	}
668 
669 	if (type == ACPI_BUS_REMOVAL_EJECT) {
670 		if (acpi_processor_handle_eject(pr))
671 			return_VALUE(-EINVAL);
672 	}
673 
674 	acpi_processor_power_exit(pr, device);
675 
676 	status = acpi_remove_notify_handler(pr->handle, ACPI_DEVICE_NOTIFY,
677 					    acpi_processor_notify);
678 	if (ACPI_FAILURE(status)) {
679 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
680 				  "Error removing notify handler\n"));
681 	}
682 
683 	acpi_processor_remove_fs(device);
684 
685 	processors[pr->id] = NULL;
686 
687 	kfree(pr);
688 
689 	return_VALUE(0);
690 }
691 
692 #ifdef CONFIG_ACPI_HOTPLUG_CPU
693 /****************************************************************************
694  * 	Acpi processor hotplug support 				       	    *
695  ****************************************************************************/
696 
697 static int is_processor_present(acpi_handle handle);
698 
699 static int is_processor_present(acpi_handle handle)
700 {
701 	acpi_status status;
702 	unsigned long sta = 0;
703 
704 	ACPI_FUNCTION_TRACE("is_processor_present");
705 
706 	status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
707 	if (ACPI_FAILURE(status) || !(sta & ACPI_STA_PRESENT)) {
708 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
709 				  "Processor Device is not present\n"));
710 		return_VALUE(0);
711 	}
712 	return_VALUE(1);
713 }
714 
715 static
716 int acpi_processor_device_add(acpi_handle handle, struct acpi_device **device)
717 {
718 	acpi_handle phandle;
719 	struct acpi_device *pdev;
720 	struct acpi_processor *pr;
721 
722 	ACPI_FUNCTION_TRACE("acpi_processor_device_add");
723 
724 	if (acpi_get_parent(handle, &phandle)) {
725 		return_VALUE(-ENODEV);
726 	}
727 
728 	if (acpi_bus_get_device(phandle, &pdev)) {
729 		return_VALUE(-ENODEV);
730 	}
731 
732 	if (acpi_bus_add(device, pdev, handle, ACPI_BUS_TYPE_PROCESSOR)) {
733 		return_VALUE(-ENODEV);
734 	}
735 
736 	acpi_bus_start(*device);
737 
738 	pr = acpi_driver_data(*device);
739 	if (!pr)
740 		return_VALUE(-ENODEV);
741 
742 	if ((pr->id >= 0) && (pr->id < NR_CPUS)) {
743 		kobject_uevent(&(*device)->kobj, KOBJ_ONLINE);
744 	}
745 	return_VALUE(0);
746 }
747 
748 static void
749 acpi_processor_hotplug_notify(acpi_handle handle, u32 event, void *data)
750 {
751 	struct acpi_processor *pr;
752 	struct acpi_device *device = NULL;
753 	int result;
754 
755 	ACPI_FUNCTION_TRACE("acpi_processor_hotplug_notify");
756 
757 	switch (event) {
758 	case ACPI_NOTIFY_BUS_CHECK:
759 	case ACPI_NOTIFY_DEVICE_CHECK:
760 		printk("Processor driver received %s event\n",
761 		       (event == ACPI_NOTIFY_BUS_CHECK) ?
762 		       "ACPI_NOTIFY_BUS_CHECK" : "ACPI_NOTIFY_DEVICE_CHECK");
763 
764 		if (!is_processor_present(handle))
765 			break;
766 
767 		if (acpi_bus_get_device(handle, &device)) {
768 			result = acpi_processor_device_add(handle, &device);
769 			if (result)
770 				ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
771 						  "Unable to add the device\n"));
772 			break;
773 		}
774 
775 		pr = acpi_driver_data(device);
776 		if (!pr) {
777 			ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
778 					  "Driver data is NULL\n"));
779 			break;
780 		}
781 
782 		if (pr->id >= 0 && (pr->id < NR_CPUS)) {
783 			kobject_uevent(&device->kobj, KOBJ_OFFLINE);
784 			break;
785 		}
786 
787 		result = acpi_processor_start(device);
788 		if ((!result) && ((pr->id >= 0) && (pr->id < NR_CPUS))) {
789 			kobject_uevent(&device->kobj, KOBJ_ONLINE);
790 		} else {
791 			ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
792 					  "Device [%s] failed to start\n",
793 					  acpi_device_bid(device)));
794 		}
795 		break;
796 	case ACPI_NOTIFY_EJECT_REQUEST:
797 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
798 				  "received ACPI_NOTIFY_EJECT_REQUEST\n"));
799 
800 		if (acpi_bus_get_device(handle, &device)) {
801 			ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
802 					  "Device don't exist, dropping EJECT\n"));
803 			break;
804 		}
805 		pr = acpi_driver_data(device);
806 		if (!pr) {
807 			ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
808 					  "Driver data is NULL, dropping EJECT\n"));
809 			return_VOID;
810 		}
811 
812 		if ((pr->id < NR_CPUS) && (cpu_present(pr->id)))
813 			kobject_uevent(&device->kobj, KOBJ_OFFLINE);
814 		break;
815 	default:
816 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
817 				  "Unsupported event [0x%x]\n", event));
818 		break;
819 	}
820 
821 	return_VOID;
822 }
823 
824 static acpi_status
825 processor_walk_namespace_cb(acpi_handle handle,
826 			    u32 lvl, void *context, void **rv)
827 {
828 	acpi_status status;
829 	int *action = context;
830 	acpi_object_type type = 0;
831 
832 	status = acpi_get_type(handle, &type);
833 	if (ACPI_FAILURE(status))
834 		return (AE_OK);
835 
836 	if (type != ACPI_TYPE_PROCESSOR)
837 		return (AE_OK);
838 
839 	switch (*action) {
840 	case INSTALL_NOTIFY_HANDLER:
841 		acpi_install_notify_handler(handle,
842 					    ACPI_SYSTEM_NOTIFY,
843 					    acpi_processor_hotplug_notify,
844 					    NULL);
845 		break;
846 	case UNINSTALL_NOTIFY_HANDLER:
847 		acpi_remove_notify_handler(handle,
848 					   ACPI_SYSTEM_NOTIFY,
849 					   acpi_processor_hotplug_notify);
850 		break;
851 	default:
852 		break;
853 	}
854 
855 	return (AE_OK);
856 }
857 
858 static acpi_status acpi_processor_hotadd_init(acpi_handle handle, int *p_cpu)
859 {
860 	ACPI_FUNCTION_TRACE("acpi_processor_hotadd_init");
861 
862 	if (!is_processor_present(handle)) {
863 		return_VALUE(AE_ERROR);
864 	}
865 
866 	if (acpi_map_lsapic(handle, p_cpu))
867 		return_VALUE(AE_ERROR);
868 
869 	if (arch_register_cpu(*p_cpu)) {
870 		acpi_unmap_lsapic(*p_cpu);
871 		return_VALUE(AE_ERROR);
872 	}
873 
874 	return_VALUE(AE_OK);
875 }
876 
877 static int acpi_processor_handle_eject(struct acpi_processor *pr)
878 {
879 	if (cpu_online(pr->id)) {
880 		return (-EINVAL);
881 	}
882 	arch_unregister_cpu(pr->id);
883 	acpi_unmap_lsapic(pr->id);
884 	return (0);
885 }
886 #else
887 static acpi_status acpi_processor_hotadd_init(acpi_handle handle, int *p_cpu)
888 {
889 	return AE_ERROR;
890 }
891 static int acpi_processor_handle_eject(struct acpi_processor *pr)
892 {
893 	return (-EINVAL);
894 }
895 #endif
896 
897 static
898 void acpi_processor_install_hotplug_notify(void)
899 {
900 #ifdef CONFIG_ACPI_HOTPLUG_CPU
901 	int action = INSTALL_NOTIFY_HANDLER;
902 	acpi_walk_namespace(ACPI_TYPE_PROCESSOR,
903 			    ACPI_ROOT_OBJECT,
904 			    ACPI_UINT32_MAX,
905 			    processor_walk_namespace_cb, &action, NULL);
906 #endif
907 }
908 
909 static
910 void acpi_processor_uninstall_hotplug_notify(void)
911 {
912 #ifdef CONFIG_ACPI_HOTPLUG_CPU
913 	int action = UNINSTALL_NOTIFY_HANDLER;
914 	acpi_walk_namespace(ACPI_TYPE_PROCESSOR,
915 			    ACPI_ROOT_OBJECT,
916 			    ACPI_UINT32_MAX,
917 			    processor_walk_namespace_cb, &action, NULL);
918 #endif
919 }
920 
921 /*
922  * We keep the driver loaded even when ACPI is not running.
923  * This is needed for the powernow-k8 driver, that works even without
924  * ACPI, but needs symbols from this driver
925  */
926 
927 static int __init acpi_processor_init(void)
928 {
929 	int result = 0;
930 
931 	ACPI_FUNCTION_TRACE("acpi_processor_init");
932 
933 	memset(&processors, 0, sizeof(processors));
934 	memset(&errata, 0, sizeof(errata));
935 
936 	acpi_processor_dir = proc_mkdir(ACPI_PROCESSOR_CLASS, acpi_root_dir);
937 	if (!acpi_processor_dir)
938 		return_VALUE(0);
939 	acpi_processor_dir->owner = THIS_MODULE;
940 
941 	result = acpi_bus_register_driver(&acpi_processor_driver);
942 	if (result < 0) {
943 		remove_proc_entry(ACPI_PROCESSOR_CLASS, acpi_root_dir);
944 		return_VALUE(0);
945 	}
946 
947 	acpi_processor_install_hotplug_notify();
948 
949 	acpi_thermal_cpufreq_init();
950 
951 	acpi_processor_ppc_init();
952 
953 	return_VALUE(0);
954 }
955 
956 static void __exit acpi_processor_exit(void)
957 {
958 	ACPI_FUNCTION_TRACE("acpi_processor_exit");
959 
960 	acpi_processor_ppc_exit();
961 
962 	acpi_thermal_cpufreq_exit();
963 
964 	acpi_processor_uninstall_hotplug_notify();
965 
966 	acpi_bus_unregister_driver(&acpi_processor_driver);
967 
968 	remove_proc_entry(ACPI_PROCESSOR_CLASS, acpi_root_dir);
969 
970 	return_VOID;
971 }
972 
973 module_init(acpi_processor_init);
974 module_exit(acpi_processor_exit);
975 
976 EXPORT_SYMBOL(acpi_processor_set_thermal_limit);
977 
978 MODULE_ALIAS("processor");
979