xref: /linux/drivers/acpi/processor_core.c (revision 9ce7677cfd7cd871adb457c80bea3b581b839641)
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 
257 int acpi_processor_set_pdc(struct acpi_processor *pr,
258 			   struct acpi_object_list *pdc_in)
259 {
260 	acpi_status status = AE_OK;
261 	u32 arg0_buf[3];
262 	union acpi_object arg0 = { ACPI_TYPE_BUFFER };
263 	struct acpi_object_list no_object = { 1, &arg0 };
264 	struct acpi_object_list *pdc;
265 
266 	ACPI_FUNCTION_TRACE("acpi_processor_set_pdc");
267 
268 	arg0.buffer.length = 12;
269 	arg0.buffer.pointer = (u8 *) arg0_buf;
270 	arg0_buf[0] = ACPI_PDC_REVISION_ID;
271 	arg0_buf[1] = 0;
272 	arg0_buf[2] = 0;
273 
274 	pdc = (pdc_in) ? pdc_in : &no_object;
275 
276 	status = acpi_evaluate_object(pr->handle, "_PDC", pdc, NULL);
277 
278 	if ((ACPI_FAILURE(status)) && (pdc_in))
279 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
280 				  "Error evaluating _PDC, using legacy perf. control...\n"));
281 
282 	return_VALUE(status);
283 }
284 
285 /* --------------------------------------------------------------------------
286                               FS Interface (/proc)
287    -------------------------------------------------------------------------- */
288 
289 static struct proc_dir_entry *acpi_processor_dir = NULL;
290 
291 static int acpi_processor_info_seq_show(struct seq_file *seq, void *offset)
292 {
293 	struct acpi_processor *pr = (struct acpi_processor *)seq->private;
294 
295 	ACPI_FUNCTION_TRACE("acpi_processor_info_seq_show");
296 
297 	if (!pr)
298 		goto end;
299 
300 	seq_printf(seq, "processor id:            %d\n"
301 		   "acpi id:                 %d\n"
302 		   "bus mastering control:   %s\n"
303 		   "power management:        %s\n"
304 		   "throttling control:      %s\n"
305 		   "limit interface:         %s\n",
306 		   pr->id,
307 		   pr->acpi_id,
308 		   pr->flags.bm_control ? "yes" : "no",
309 		   pr->flags.power ? "yes" : "no",
310 		   pr->flags.throttling ? "yes" : "no",
311 		   pr->flags.limit ? "yes" : "no");
312 
313       end:
314 	return_VALUE(0);
315 }
316 
317 static int acpi_processor_info_open_fs(struct inode *inode, struct file *file)
318 {
319 	return single_open(file, acpi_processor_info_seq_show,
320 			   PDE(inode)->data);
321 }
322 
323 static int acpi_processor_add_fs(struct acpi_device *device)
324 {
325 	struct proc_dir_entry *entry = NULL;
326 
327 	ACPI_FUNCTION_TRACE("acpi_processor_add_fs");
328 
329 	if (!acpi_device_dir(device)) {
330 		acpi_device_dir(device) = proc_mkdir(acpi_device_bid(device),
331 						     acpi_processor_dir);
332 		if (!acpi_device_dir(device))
333 			return_VALUE(-ENODEV);
334 	}
335 	acpi_device_dir(device)->owner = THIS_MODULE;
336 
337 	/* 'info' [R] */
338 	entry = create_proc_entry(ACPI_PROCESSOR_FILE_INFO,
339 				  S_IRUGO, acpi_device_dir(device));
340 	if (!entry)
341 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
342 				  "Unable to create '%s' fs entry\n",
343 				  ACPI_PROCESSOR_FILE_INFO));
344 	else {
345 		entry->proc_fops = &acpi_processor_info_fops;
346 		entry->data = acpi_driver_data(device);
347 		entry->owner = THIS_MODULE;
348 	}
349 
350 	/* 'throttling' [R/W] */
351 	entry = create_proc_entry(ACPI_PROCESSOR_FILE_THROTTLING,
352 				  S_IFREG | S_IRUGO | S_IWUSR,
353 				  acpi_device_dir(device));
354 	if (!entry)
355 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
356 				  "Unable to create '%s' fs entry\n",
357 				  ACPI_PROCESSOR_FILE_THROTTLING));
358 	else {
359 		entry->proc_fops = &acpi_processor_throttling_fops;
360 		entry->proc_fops->write = acpi_processor_write_throttling;
361 		entry->data = acpi_driver_data(device);
362 		entry->owner = THIS_MODULE;
363 	}
364 
365 	/* 'limit' [R/W] */
366 	entry = create_proc_entry(ACPI_PROCESSOR_FILE_LIMIT,
367 				  S_IFREG | S_IRUGO | S_IWUSR,
368 				  acpi_device_dir(device));
369 	if (!entry)
370 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
371 				  "Unable to create '%s' fs entry\n",
372 				  ACPI_PROCESSOR_FILE_LIMIT));
373 	else {
374 		entry->proc_fops = &acpi_processor_limit_fops;
375 		entry->proc_fops->write = acpi_processor_write_limit;
376 		entry->data = acpi_driver_data(device);
377 		entry->owner = THIS_MODULE;
378 	}
379 
380 	return_VALUE(0);
381 }
382 
383 static int acpi_processor_remove_fs(struct acpi_device *device)
384 {
385 	ACPI_FUNCTION_TRACE("acpi_processor_remove_fs");
386 
387 	if (acpi_device_dir(device)) {
388 		remove_proc_entry(ACPI_PROCESSOR_FILE_INFO,
389 				  acpi_device_dir(device));
390 		remove_proc_entry(ACPI_PROCESSOR_FILE_THROTTLING,
391 				  acpi_device_dir(device));
392 		remove_proc_entry(ACPI_PROCESSOR_FILE_LIMIT,
393 				  acpi_device_dir(device));
394 		remove_proc_entry(acpi_device_bid(device), acpi_processor_dir);
395 		acpi_device_dir(device) = NULL;
396 	}
397 
398 	return_VALUE(0);
399 }
400 
401 /* Use the acpiid in MADT to map cpus in case of SMP */
402 #ifndef CONFIG_SMP
403 #define convert_acpiid_to_cpu(acpi_id) (0xff)
404 #else
405 
406 #ifdef CONFIG_IA64
407 #define arch_acpiid_to_apicid 	ia64_acpiid_to_sapicid
408 #define arch_cpu_to_apicid 	ia64_cpu_to_sapicid
409 #define ARCH_BAD_APICID		(0xffff)
410 #else
411 #define arch_acpiid_to_apicid 	x86_acpiid_to_apicid
412 #define arch_cpu_to_apicid 	x86_cpu_to_apicid
413 #define ARCH_BAD_APICID		(0xff)
414 #endif
415 
416 static u8 convert_acpiid_to_cpu(u8 acpi_id)
417 {
418 	u16 apic_id;
419 	int i;
420 
421 	apic_id = arch_acpiid_to_apicid[acpi_id];
422 	if (apic_id == ARCH_BAD_APICID)
423 		return -1;
424 
425 	for (i = 0; i < NR_CPUS; i++) {
426 		if (arch_cpu_to_apicid[i] == apic_id)
427 			return i;
428 	}
429 	return -1;
430 }
431 #endif
432 
433 /* --------------------------------------------------------------------------
434                                  Driver Interface
435    -------------------------------------------------------------------------- */
436 
437 static int acpi_processor_get_info(struct acpi_processor *pr)
438 {
439 	acpi_status status = 0;
440 	union acpi_object object = { 0 };
441 	struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
442 	u8 cpu_index;
443 	static int cpu0_initialized;
444 
445 	ACPI_FUNCTION_TRACE("acpi_processor_get_info");
446 
447 	if (!pr)
448 		return_VALUE(-EINVAL);
449 
450 	if (num_online_cpus() > 1)
451 		errata.smp = TRUE;
452 
453 	acpi_processor_errata(pr);
454 
455 	/*
456 	 * Check to see if we have bus mastering arbitration control.  This
457 	 * is required for proper C3 usage (to maintain cache coherency).
458 	 */
459 	if (acpi_fadt.V1_pm2_cnt_blk && acpi_fadt.pm2_cnt_len) {
460 		pr->flags.bm_control = 1;
461 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
462 				  "Bus mastering arbitration control present\n"));
463 	} else
464 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
465 				  "No bus mastering arbitration control\n"));
466 
467 	/*
468 	 * Evalute the processor object.  Note that it is common on SMP to
469 	 * have the first (boot) processor with a valid PBLK address while
470 	 * all others have a NULL address.
471 	 */
472 	status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer);
473 	if (ACPI_FAILURE(status)) {
474 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
475 				  "Error evaluating processor object\n"));
476 		return_VALUE(-ENODEV);
477 	}
478 
479 	/*
480 	 * TBD: Synch processor ID (via LAPIC/LSAPIC structures) on SMP.
481 	 *      >>> 'acpi_get_processor_id(acpi_id, &id)' in arch/xxx/acpi.c
482 	 */
483 	pr->acpi_id = object.processor.proc_id;
484 
485 	cpu_index = convert_acpiid_to_cpu(pr->acpi_id);
486 
487 	/* Handle UP system running SMP kernel, with no LAPIC in MADT */
488 	if (!cpu0_initialized && (cpu_index == 0xff) &&
489 	    (num_online_cpus() == 1)) {
490 		cpu_index = 0;
491 	}
492 
493 	cpu0_initialized = 1;
494 
495 	pr->id = cpu_index;
496 
497 	/*
498 	 *  Extra Processor objects may be enumerated on MP systems with
499 	 *  less than the max # of CPUs. They should be ignored _iff
500 	 *  they are physically not present.
501 	 */
502 	if (cpu_index >= NR_CPUS) {
503 		if (ACPI_FAILURE
504 		    (acpi_processor_hotadd_init(pr->handle, &pr->id))) {
505 			ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
506 					  "Error getting cpuindex for acpiid 0x%x\n",
507 					  pr->acpi_id));
508 			return_VALUE(-ENODEV);
509 		}
510 	}
511 
512 	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id,
513 			  pr->acpi_id));
514 
515 	if (!object.processor.pblk_address)
516 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n"));
517 	else if (object.processor.pblk_length != 6)
518 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid PBLK length [%d]\n",
519 				  object.processor.pblk_length));
520 	else {
521 		pr->throttling.address = object.processor.pblk_address;
522 		pr->throttling.duty_offset = acpi_fadt.duty_offset;
523 		pr->throttling.duty_width = acpi_fadt.duty_width;
524 
525 		pr->pblk = object.processor.pblk_address;
526 
527 		/*
528 		 * We don't care about error returns - we just try to mark
529 		 * these reserved so that nobody else is confused into thinking
530 		 * that this region might be unused..
531 		 *
532 		 * (In particular, allocating the IO range for Cardbus)
533 		 */
534 		request_region(pr->throttling.address, 6, "ACPI CPU throttle");
535 	}
536 
537 #ifdef CONFIG_CPU_FREQ
538 	acpi_processor_ppc_has_changed(pr);
539 #endif
540 	acpi_processor_get_throttling_info(pr);
541 	acpi_processor_get_limit_info(pr);
542 
543 	return_VALUE(0);
544 }
545 
546 static void *processor_device_array[NR_CPUS];
547 
548 static int acpi_processor_start(struct acpi_device *device)
549 {
550 	int result = 0;
551 	acpi_status status = AE_OK;
552 	struct acpi_processor *pr;
553 
554 	ACPI_FUNCTION_TRACE("acpi_processor_start");
555 
556 	pr = acpi_driver_data(device);
557 
558 	result = acpi_processor_get_info(pr);
559 	if (result) {
560 		/* Processor is physically not present */
561 		return_VALUE(0);
562 	}
563 
564 	BUG_ON((pr->id >= NR_CPUS) || (pr->id < 0));
565 
566 	/*
567 	 * Buggy BIOS check
568 	 * ACPI id of processors can be reported wrongly by the BIOS.
569 	 * Don't trust it blindly
570 	 */
571 	if (processor_device_array[pr->id] != NULL &&
572 	    processor_device_array[pr->id] != (void *)device) {
573 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "BIOS reporting wrong ACPI id"
574 			"for the processor\n"));
575 		return_VALUE(-ENODEV);
576 	}
577 	processor_device_array[pr->id] = (void *)device;
578 
579 	processors[pr->id] = pr;
580 
581 	result = acpi_processor_add_fs(device);
582 	if (result)
583 		goto end;
584 
585 	status = acpi_install_notify_handler(pr->handle, ACPI_DEVICE_NOTIFY,
586 					     acpi_processor_notify, pr);
587 	if (ACPI_FAILURE(status)) {
588 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
589 				  "Error installing device notify handler\n"));
590 	}
591 
592 	acpi_processor_power_init(pr, device);
593 
594 	if (pr->flags.throttling) {
595 		printk(KERN_INFO PREFIX "%s [%s] (supports",
596 		       acpi_device_name(device), acpi_device_bid(device));
597 		printk(" %d throttling states", pr->throttling.state_count);
598 		printk(")\n");
599 	}
600 
601       end:
602 
603 	return_VALUE(result);
604 }
605 
606 static void acpi_processor_notify(acpi_handle handle, u32 event, void *data)
607 {
608 	struct acpi_processor *pr = (struct acpi_processor *)data;
609 	struct acpi_device *device = NULL;
610 
611 	ACPI_FUNCTION_TRACE("acpi_processor_notify");
612 
613 	if (!pr)
614 		return_VOID;
615 
616 	if (acpi_bus_get_device(pr->handle, &device))
617 		return_VOID;
618 
619 	switch (event) {
620 	case ACPI_PROCESSOR_NOTIFY_PERFORMANCE:
621 		acpi_processor_ppc_has_changed(pr);
622 		acpi_bus_generate_event(device, event,
623 					pr->performance_platform_limit);
624 		break;
625 	case ACPI_PROCESSOR_NOTIFY_POWER:
626 		acpi_processor_cst_has_changed(pr);
627 		acpi_bus_generate_event(device, event, 0);
628 		break;
629 	default:
630 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
631 				  "Unsupported event [0x%x]\n", event));
632 		break;
633 	}
634 
635 	return_VOID;
636 }
637 
638 static int acpi_processor_add(struct acpi_device *device)
639 {
640 	struct acpi_processor *pr = NULL;
641 
642 	ACPI_FUNCTION_TRACE("acpi_processor_add");
643 
644 	if (!device)
645 		return_VALUE(-EINVAL);
646 
647 	pr = kmalloc(sizeof(struct acpi_processor), GFP_KERNEL);
648 	if (!pr)
649 		return_VALUE(-ENOMEM);
650 	memset(pr, 0, sizeof(struct acpi_processor));
651 
652 	pr->handle = device->handle;
653 	strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
654 	strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
655 	acpi_driver_data(device) = pr;
656 
657 	return_VALUE(0);
658 }
659 
660 static int acpi_processor_remove(struct acpi_device *device, int type)
661 {
662 	acpi_status status = AE_OK;
663 	struct acpi_processor *pr = NULL;
664 
665 	ACPI_FUNCTION_TRACE("acpi_processor_remove");
666 
667 	if (!device || !acpi_driver_data(device))
668 		return_VALUE(-EINVAL);
669 
670 	pr = (struct acpi_processor *)acpi_driver_data(device);
671 
672 	if (pr->id >= NR_CPUS) {
673 		kfree(pr);
674 		return_VALUE(0);
675 	}
676 
677 	if (type == ACPI_BUS_REMOVAL_EJECT) {
678 		if (acpi_processor_handle_eject(pr))
679 			return_VALUE(-EINVAL);
680 	}
681 
682 	acpi_processor_power_exit(pr, device);
683 
684 	status = acpi_remove_notify_handler(pr->handle, ACPI_DEVICE_NOTIFY,
685 					    acpi_processor_notify);
686 	if (ACPI_FAILURE(status)) {
687 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
688 				  "Error removing notify handler\n"));
689 	}
690 
691 	acpi_processor_remove_fs(device);
692 
693 	processors[pr->id] = NULL;
694 
695 	kfree(pr);
696 
697 	return_VALUE(0);
698 }
699 
700 #ifdef CONFIG_ACPI_HOTPLUG_CPU
701 /****************************************************************************
702  * 	Acpi processor hotplug support 				       	    *
703  ****************************************************************************/
704 
705 static int is_processor_present(acpi_handle handle);
706 
707 static int is_processor_present(acpi_handle handle)
708 {
709 	acpi_status status;
710 	unsigned long sta = 0;
711 
712 	ACPI_FUNCTION_TRACE("is_processor_present");
713 
714 	status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
715 	if (ACPI_FAILURE(status) || !(sta & ACPI_STA_PRESENT)) {
716 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
717 				  "Processor Device is not present\n"));
718 		return_VALUE(0);
719 	}
720 	return_VALUE(1);
721 }
722 
723 static
724 int acpi_processor_device_add(acpi_handle handle, struct acpi_device **device)
725 {
726 	acpi_handle phandle;
727 	struct acpi_device *pdev;
728 	struct acpi_processor *pr;
729 
730 	ACPI_FUNCTION_TRACE("acpi_processor_device_add");
731 
732 	if (acpi_get_parent(handle, &phandle)) {
733 		return_VALUE(-ENODEV);
734 	}
735 
736 	if (acpi_bus_get_device(phandle, &pdev)) {
737 		return_VALUE(-ENODEV);
738 	}
739 
740 	if (acpi_bus_add(device, pdev, handle, ACPI_BUS_TYPE_PROCESSOR)) {
741 		return_VALUE(-ENODEV);
742 	}
743 
744 	acpi_bus_start(*device);
745 
746 	pr = acpi_driver_data(*device);
747 	if (!pr)
748 		return_VALUE(-ENODEV);
749 
750 	if ((pr->id >= 0) && (pr->id < NR_CPUS)) {
751 		kobject_hotplug(&(*device)->kobj, KOBJ_ONLINE);
752 	}
753 	return_VALUE(0);
754 }
755 
756 static void
757 acpi_processor_hotplug_notify(acpi_handle handle, u32 event, void *data)
758 {
759 	struct acpi_processor *pr;
760 	struct acpi_device *device = NULL;
761 	int result;
762 
763 	ACPI_FUNCTION_TRACE("acpi_processor_hotplug_notify");
764 
765 	switch (event) {
766 	case ACPI_NOTIFY_BUS_CHECK:
767 	case ACPI_NOTIFY_DEVICE_CHECK:
768 		printk("Processor driver received %s event\n",
769 		       (event == ACPI_NOTIFY_BUS_CHECK) ?
770 		       "ACPI_NOTIFY_BUS_CHECK" : "ACPI_NOTIFY_DEVICE_CHECK");
771 
772 		if (!is_processor_present(handle))
773 			break;
774 
775 		if (acpi_bus_get_device(handle, &device)) {
776 			result = acpi_processor_device_add(handle, &device);
777 			if (result)
778 				ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
779 						  "Unable to add the device\n"));
780 			break;
781 		}
782 
783 		pr = acpi_driver_data(device);
784 		if (!pr) {
785 			ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
786 					  "Driver data is NULL\n"));
787 			break;
788 		}
789 
790 		if (pr->id >= 0 && (pr->id < NR_CPUS)) {
791 			kobject_hotplug(&device->kobj, KOBJ_OFFLINE);
792 			break;
793 		}
794 
795 		result = acpi_processor_start(device);
796 		if ((!result) && ((pr->id >= 0) && (pr->id < NR_CPUS))) {
797 			kobject_hotplug(&device->kobj, KOBJ_ONLINE);
798 		} else {
799 			ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
800 					  "Device [%s] failed to start\n",
801 					  acpi_device_bid(device)));
802 		}
803 		break;
804 	case ACPI_NOTIFY_EJECT_REQUEST:
805 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
806 				  "received ACPI_NOTIFY_EJECT_REQUEST\n"));
807 
808 		if (acpi_bus_get_device(handle, &device)) {
809 			ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
810 					  "Device don't exist, dropping EJECT\n"));
811 			break;
812 		}
813 		pr = acpi_driver_data(device);
814 		if (!pr) {
815 			ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
816 					  "Driver data is NULL, dropping EJECT\n"));
817 			return_VOID;
818 		}
819 
820 		if ((pr->id < NR_CPUS) && (cpu_present(pr->id)))
821 			kobject_hotplug(&device->kobj, KOBJ_OFFLINE);
822 		break;
823 	default:
824 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
825 				  "Unsupported event [0x%x]\n", event));
826 		break;
827 	}
828 
829 	return_VOID;
830 }
831 
832 static acpi_status
833 processor_walk_namespace_cb(acpi_handle handle,
834 			    u32 lvl, void *context, void **rv)
835 {
836 	acpi_status status;
837 	int *action = context;
838 	acpi_object_type type = 0;
839 
840 	status = acpi_get_type(handle, &type);
841 	if (ACPI_FAILURE(status))
842 		return (AE_OK);
843 
844 	if (type != ACPI_TYPE_PROCESSOR)
845 		return (AE_OK);
846 
847 	switch (*action) {
848 	case INSTALL_NOTIFY_HANDLER:
849 		acpi_install_notify_handler(handle,
850 					    ACPI_SYSTEM_NOTIFY,
851 					    acpi_processor_hotplug_notify,
852 					    NULL);
853 		break;
854 	case UNINSTALL_NOTIFY_HANDLER:
855 		acpi_remove_notify_handler(handle,
856 					   ACPI_SYSTEM_NOTIFY,
857 					   acpi_processor_hotplug_notify);
858 		break;
859 	default:
860 		break;
861 	}
862 
863 	return (AE_OK);
864 }
865 
866 static acpi_status acpi_processor_hotadd_init(acpi_handle handle, int *p_cpu)
867 {
868 	ACPI_FUNCTION_TRACE("acpi_processor_hotadd_init");
869 
870 	if (!is_processor_present(handle)) {
871 		return_VALUE(AE_ERROR);
872 	}
873 
874 	if (acpi_map_lsapic(handle, p_cpu))
875 		return_VALUE(AE_ERROR);
876 
877 	if (arch_register_cpu(*p_cpu)) {
878 		acpi_unmap_lsapic(*p_cpu);
879 		return_VALUE(AE_ERROR);
880 	}
881 
882 	return_VALUE(AE_OK);
883 }
884 
885 static int acpi_processor_handle_eject(struct acpi_processor *pr)
886 {
887 	if (cpu_online(pr->id)) {
888 		return (-EINVAL);
889 	}
890 	arch_unregister_cpu(pr->id);
891 	acpi_unmap_lsapic(pr->id);
892 	return (0);
893 }
894 #else
895 static acpi_status acpi_processor_hotadd_init(acpi_handle handle, int *p_cpu)
896 {
897 	return AE_ERROR;
898 }
899 static int acpi_processor_handle_eject(struct acpi_processor *pr)
900 {
901 	return (-EINVAL);
902 }
903 #endif
904 
905 static
906 void acpi_processor_install_hotplug_notify(void)
907 {
908 #ifdef CONFIG_ACPI_HOTPLUG_CPU
909 	int action = INSTALL_NOTIFY_HANDLER;
910 	acpi_walk_namespace(ACPI_TYPE_PROCESSOR,
911 			    ACPI_ROOT_OBJECT,
912 			    ACPI_UINT32_MAX,
913 			    processor_walk_namespace_cb, &action, NULL);
914 #endif
915 }
916 
917 static
918 void acpi_processor_uninstall_hotplug_notify(void)
919 {
920 #ifdef CONFIG_ACPI_HOTPLUG_CPU
921 	int action = UNINSTALL_NOTIFY_HANDLER;
922 	acpi_walk_namespace(ACPI_TYPE_PROCESSOR,
923 			    ACPI_ROOT_OBJECT,
924 			    ACPI_UINT32_MAX,
925 			    processor_walk_namespace_cb, &action, NULL);
926 #endif
927 }
928 
929 /*
930  * We keep the driver loaded even when ACPI is not running.
931  * This is needed for the powernow-k8 driver, that works even without
932  * ACPI, but needs symbols from this driver
933  */
934 
935 static int __init acpi_processor_init(void)
936 {
937 	int result = 0;
938 
939 	ACPI_FUNCTION_TRACE("acpi_processor_init");
940 
941 	memset(&processors, 0, sizeof(processors));
942 	memset(&errata, 0, sizeof(errata));
943 
944 	acpi_processor_dir = proc_mkdir(ACPI_PROCESSOR_CLASS, acpi_root_dir);
945 	if (!acpi_processor_dir)
946 		return_VALUE(0);
947 	acpi_processor_dir->owner = THIS_MODULE;
948 
949 	result = acpi_bus_register_driver(&acpi_processor_driver);
950 	if (result < 0) {
951 		remove_proc_entry(ACPI_PROCESSOR_CLASS, acpi_root_dir);
952 		return_VALUE(0);
953 	}
954 
955 	acpi_processor_install_hotplug_notify();
956 
957 	acpi_thermal_cpufreq_init();
958 
959 	acpi_processor_ppc_init();
960 
961 	return_VALUE(0);
962 }
963 
964 static void __exit acpi_processor_exit(void)
965 {
966 	ACPI_FUNCTION_TRACE("acpi_processor_exit");
967 
968 	acpi_processor_ppc_exit();
969 
970 	acpi_thermal_cpufreq_exit();
971 
972 	acpi_processor_uninstall_hotplug_notify();
973 
974 	acpi_bus_unregister_driver(&acpi_processor_driver);
975 
976 	remove_proc_entry(ACPI_PROCESSOR_CLASS, acpi_root_dir);
977 
978 	return_VOID;
979 }
980 
981 module_init(acpi_processor_init);
982 module_exit(acpi_processor_exit);
983 
984 EXPORT_SYMBOL(acpi_processor_set_thermal_limit);
985 
986 MODULE_ALIAS("processor");
987