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/dmi.h>
44 #include <linux/moduleparam.h>
45 #include <linux/cpuidle.h>
46 #include <linux/slab.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 PREFIX "ACPI: "
62
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_driver");
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_remove(struct acpi_device *device, int type);
84 static void acpi_processor_notify(struct acpi_device *device, u32 event);
85 static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr);
86 static int acpi_processor_handle_eject(struct acpi_processor *pr);
87 static int acpi_processor_start(struct acpi_processor *pr);
88
89 static const struct acpi_device_id processor_device_ids[] = {
90 {ACPI_PROCESSOR_OBJECT_HID, 0},
91 {"ACPI0007", 0},
92 {"", 0},
93 };
94 MODULE_DEVICE_TABLE(acpi, processor_device_ids);
95
96 static struct acpi_driver acpi_processor_driver = {
97 .name = "processor",
98 .class = ACPI_PROCESSOR_CLASS,
99 .ids = processor_device_ids,
100 .ops = {
101 .add = acpi_processor_add,
102 .remove = acpi_processor_remove,
103 .suspend = acpi_processor_suspend,
104 .resume = acpi_processor_resume,
105 .notify = acpi_processor_notify,
106 },
107 };
108
109 #define INSTALL_NOTIFY_HANDLER 1
110 #define UNINSTALL_NOTIFY_HANDLER 2
111
112 DEFINE_PER_CPU(struct acpi_processor *, processors);
113 EXPORT_PER_CPU_SYMBOL(processors);
114
115 struct acpi_processor_errata errata __read_mostly;
116
117 /* --------------------------------------------------------------------------
118 Errata Handling
119 -------------------------------------------------------------------------- */
120
acpi_processor_errata_piix4(struct pci_dev * dev)121 static int acpi_processor_errata_piix4(struct pci_dev *dev)
122 {
123 u8 value1 = 0;
124 u8 value2 = 0;
125
126
127 if (!dev)
128 return -EINVAL;
129
130 /*
131 * Note that 'dev' references the PIIX4 ACPI Controller.
132 */
133
134 switch (dev->revision) {
135 case 0:
136 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 A-step\n"));
137 break;
138 case 1:
139 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 B-step\n"));
140 break;
141 case 2:
142 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4E\n"));
143 break;
144 case 3:
145 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4M\n"));
146 break;
147 default:
148 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found unknown PIIX4\n"));
149 break;
150 }
151
152 switch (dev->revision) {
153
154 case 0: /* PIIX4 A-step */
155 case 1: /* PIIX4 B-step */
156 /*
157 * See specification changes #13 ("Manual Throttle Duty Cycle")
158 * and #14 ("Enabling and Disabling Manual Throttle"), plus
159 * erratum #5 ("STPCLK# Deassertion Time") from the January
160 * 2002 PIIX4 specification update. Applies to only older
161 * PIIX4 models.
162 */
163 errata.piix4.throttle = 1;
164
165 case 2: /* PIIX4E */
166 case 3: /* PIIX4M */
167 /*
168 * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA
169 * Livelock") from the January 2002 PIIX4 specification update.
170 * Applies to all PIIX4 models.
171 */
172
173 /*
174 * BM-IDE
175 * ------
176 * Find the PIIX4 IDE Controller and get the Bus Master IDE
177 * Status register address. We'll use this later to read
178 * each IDE controller's DMA status to make sure we catch all
179 * DMA activity.
180 */
181 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
182 PCI_DEVICE_ID_INTEL_82371AB,
183 PCI_ANY_ID, PCI_ANY_ID, NULL);
184 if (dev) {
185 errata.piix4.bmisx = pci_resource_start(dev, 4);
186 pci_dev_put(dev);
187 }
188
189 /*
190 * Type-F DMA
191 * ----------
192 * Find the PIIX4 ISA Controller and read the Motherboard
193 * DMA controller's status to see if Type-F (Fast) DMA mode
194 * is enabled (bit 7) on either channel. Note that we'll
195 * disable C3 support if this is enabled, as some legacy
196 * devices won't operate well if fast DMA is disabled.
197 */
198 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
199 PCI_DEVICE_ID_INTEL_82371AB_0,
200 PCI_ANY_ID, PCI_ANY_ID, NULL);
201 if (dev) {
202 pci_read_config_byte(dev, 0x76, &value1);
203 pci_read_config_byte(dev, 0x77, &value2);
204 if ((value1 & 0x80) || (value2 & 0x80))
205 errata.piix4.fdma = 1;
206 pci_dev_put(dev);
207 }
208
209 break;
210 }
211
212 if (errata.piix4.bmisx)
213 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
214 "Bus master activity detection (BM-IDE) erratum enabled\n"));
215 if (errata.piix4.fdma)
216 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
217 "Type-F DMA livelock erratum (C3 disabled)\n"));
218
219 return 0;
220 }
221
acpi_processor_errata(struct acpi_processor * pr)222 static int acpi_processor_errata(struct acpi_processor *pr)
223 {
224 int result = 0;
225 struct pci_dev *dev = NULL;
226
227
228 if (!pr)
229 return -EINVAL;
230
231 /*
232 * PIIX4
233 */
234 dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
235 PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID,
236 PCI_ANY_ID, NULL);
237 if (dev) {
238 result = acpi_processor_errata_piix4(dev);
239 pci_dev_put(dev);
240 }
241
242 return result;
243 }
244
245 /* --------------------------------------------------------------------------
246 Driver Interface
247 -------------------------------------------------------------------------- */
248
acpi_processor_get_info(struct acpi_device * device)249 static int acpi_processor_get_info(struct acpi_device *device)
250 {
251 acpi_status status = 0;
252 union acpi_object object = { 0 };
253 struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
254 struct acpi_processor *pr;
255 int cpu_index, device_declaration = 0;
256 static int cpu0_initialized;
257
258 pr = acpi_driver_data(device);
259 if (!pr)
260 return -EINVAL;
261
262 if (num_online_cpus() > 1)
263 errata.smp = TRUE;
264
265 acpi_processor_errata(pr);
266
267 /*
268 * Check to see if we have bus mastering arbitration control. This
269 * is required for proper C3 usage (to maintain cache coherency).
270 */
271 if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) {
272 pr->flags.bm_control = 1;
273 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
274 "Bus mastering arbitration control present\n"));
275 } else
276 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
277 "No bus mastering arbitration control\n"));
278
279 if (!strcmp(acpi_device_hid(device), ACPI_PROCESSOR_OBJECT_HID)) {
280 /* Declared with "Processor" statement; match ProcessorID */
281 status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer);
282 if (ACPI_FAILURE(status)) {
283 printk(KERN_ERR PREFIX "Evaluating processor object\n");
284 return -ENODEV;
285 }
286
287 /*
288 * TBD: Synch processor ID (via LAPIC/LSAPIC structures) on SMP.
289 * >>> 'acpi_get_processor_id(acpi_id, &id)' in
290 * arch/xxx/acpi.c
291 */
292 pr->acpi_id = object.processor.proc_id;
293 } else {
294 /*
295 * Declared with "Device" statement; match _UID.
296 * Note that we don't handle string _UIDs yet.
297 */
298 unsigned long long value;
299 status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID,
300 NULL, &value);
301 if (ACPI_FAILURE(status)) {
302 printk(KERN_ERR PREFIX
303 "Evaluating processor _UID [%#x]\n", status);
304 return -ENODEV;
305 }
306 device_declaration = 1;
307 pr->acpi_id = value;
308 }
309 cpu_index = acpi_get_cpuid(pr->handle, device_declaration, pr->acpi_id);
310
311 /* Handle UP system running SMP kernel, with no LAPIC in MADT */
312 if (!cpu0_initialized && (cpu_index == -1) &&
313 (num_online_cpus() == 1)) {
314 cpu_index = 0;
315 }
316
317 cpu0_initialized = 1;
318
319 pr->id = cpu_index;
320
321 /*
322 * Extra Processor objects may be enumerated on MP systems with
323 * less than the max # of CPUs. They should be ignored _iff
324 * they are physically not present.
325 */
326 if (pr->id == -1) {
327 if (ACPI_FAILURE(acpi_processor_hotadd_init(pr)))
328 return -ENODEV;
329 }
330 /*
331 * On some boxes several processors use the same processor bus id.
332 * But they are located in different scope. For example:
333 * \_SB.SCK0.CPU0
334 * \_SB.SCK1.CPU0
335 * Rename the processor device bus id. And the new bus id will be
336 * generated as the following format:
337 * CPU+CPU ID.
338 */
339 sprintf(acpi_device_bid(device), "CPU%X", pr->id);
340 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id,
341 pr->acpi_id));
342
343 if (!object.processor.pblk_address)
344 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n"));
345 else if (object.processor.pblk_length != 6)
346 printk(KERN_ERR PREFIX "Invalid PBLK length [%d]\n",
347 object.processor.pblk_length);
348 else {
349 pr->throttling.address = object.processor.pblk_address;
350 pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset;
351 pr->throttling.duty_width = acpi_gbl_FADT.duty_width;
352
353 pr->pblk = object.processor.pblk_address;
354
355 /*
356 * We don't care about error returns - we just try to mark
357 * these reserved so that nobody else is confused into thinking
358 * that this region might be unused..
359 *
360 * (In particular, allocating the IO range for Cardbus)
361 */
362 request_region(pr->throttling.address, 6, "ACPI CPU throttle");
363 }
364
365 /*
366 * If ACPI describes a slot number for this CPU, we can use it
367 * ensure we get the right value in the "physical id" field
368 * of /proc/cpuinfo
369 */
370 status = acpi_evaluate_object(pr->handle, "_SUN", NULL, &buffer);
371 if (ACPI_SUCCESS(status))
372 arch_fix_phys_package_id(pr->id, object.integer.value);
373
374 return 0;
375 }
376
377 static DEFINE_PER_CPU(void *, processor_device_array);
378
acpi_processor_notify(struct acpi_device * device,u32 event)379 static void acpi_processor_notify(struct acpi_device *device, u32 event)
380 {
381 struct acpi_processor *pr = acpi_driver_data(device);
382 int saved;
383
384 if (!pr)
385 return;
386
387 switch (event) {
388 case ACPI_PROCESSOR_NOTIFY_PERFORMANCE:
389 saved = pr->performance_platform_limit;
390 acpi_processor_ppc_has_changed(pr, 1);
391 if (saved == pr->performance_platform_limit)
392 break;
393 acpi_bus_generate_proc_event(device, event,
394 pr->performance_platform_limit);
395 acpi_bus_generate_netlink_event(device->pnp.device_class,
396 dev_name(&device->dev), event,
397 pr->performance_platform_limit);
398 break;
399 case ACPI_PROCESSOR_NOTIFY_POWER:
400 acpi_processor_cst_has_changed(pr);
401 acpi_bus_generate_proc_event(device, event, 0);
402 acpi_bus_generate_netlink_event(device->pnp.device_class,
403 dev_name(&device->dev), event, 0);
404 break;
405 case ACPI_PROCESSOR_NOTIFY_THROTTLING:
406 acpi_processor_tstate_has_changed(pr);
407 acpi_bus_generate_proc_event(device, event, 0);
408 acpi_bus_generate_netlink_event(device->pnp.device_class,
409 dev_name(&device->dev), event, 0);
410 default:
411 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
412 "Unsupported event [0x%x]\n", event));
413 break;
414 }
415
416 return;
417 }
418
acpi_cpu_soft_notify(struct notifier_block * nfb,unsigned long action,void * hcpu)419 static int acpi_cpu_soft_notify(struct notifier_block *nfb,
420 unsigned long action, void *hcpu)
421 {
422 unsigned int cpu = (unsigned long)hcpu;
423 struct acpi_processor *pr = per_cpu(processors, cpu);
424
425 if (action == CPU_ONLINE && pr) {
426 /* CPU got physically hotplugged and onlined the first time:
427 * Initialize missing things
428 */
429 if (pr->flags.need_hotplug_init) {
430 struct cpuidle_driver *idle_driver =
431 cpuidle_get_driver();
432
433 printk(KERN_INFO "Will online and init hotplugged "
434 "CPU: %d\n", pr->id);
435 WARN(acpi_processor_start(pr), "Failed to start CPU:"
436 " %d\n", pr->id);
437 pr->flags.need_hotplug_init = 0;
438 if (idle_driver && !strcmp(idle_driver->name,
439 "intel_idle")) {
440 intel_idle_cpu_init(pr->id);
441 }
442 /* Normal CPU soft online event */
443 } else {
444 acpi_processor_ppc_has_changed(pr, 0);
445 acpi_processor_cst_has_changed(pr);
446 acpi_processor_reevaluate_tstate(pr, action);
447 acpi_processor_tstate_has_changed(pr);
448 }
449 }
450 if (action == CPU_DEAD && pr) {
451 /* invalidate the flag.throttling after one CPU is offline */
452 acpi_processor_reevaluate_tstate(pr, action);
453 }
454 return NOTIFY_OK;
455 }
456
457 static struct notifier_block acpi_cpu_notifier =
458 {
459 .notifier_call = acpi_cpu_soft_notify,
460 };
461
462 /*
463 * acpi_processor_start() is called by the cpu_hotplug_notifier func:
464 * acpi_cpu_soft_notify(). Getting it __cpuinit{data} is difficult, the
465 * root cause seem to be that acpi_processor_uninstall_hotplug_notify()
466 * is in the module_exit (__exit) func. Allowing acpi_processor_start()
467 * to not be in __cpuinit section, but being called from __cpuinit funcs
468 * via __ref looks like the right thing to do here.
469 */
acpi_processor_start(struct acpi_processor * pr)470 static __ref int acpi_processor_start(struct acpi_processor *pr)
471 {
472 struct acpi_device *device = per_cpu(processor_device_array, pr->id);
473 int result = 0;
474
475 #ifdef CONFIG_CPU_FREQ
476 acpi_processor_ppc_has_changed(pr, 0);
477 #endif
478 acpi_processor_get_throttling_info(pr);
479 acpi_processor_get_limit_info(pr);
480
481 if (!cpuidle_get_driver() || cpuidle_get_driver() == &acpi_idle_driver)
482 acpi_processor_power_init(pr, device);
483
484 pr->cdev = thermal_cooling_device_register("Processor", device,
485 &processor_cooling_ops);
486 if (IS_ERR(pr->cdev)) {
487 result = PTR_ERR(pr->cdev);
488 goto err_power_exit;
489 }
490
491 dev_dbg(&device->dev, "registered as cooling_device%d\n",
492 pr->cdev->id);
493
494 result = sysfs_create_link(&device->dev.kobj,
495 &pr->cdev->device.kobj,
496 "thermal_cooling");
497 if (result) {
498 printk(KERN_ERR PREFIX "Create sysfs link\n");
499 goto err_thermal_unregister;
500 }
501 result = sysfs_create_link(&pr->cdev->device.kobj,
502 &device->dev.kobj,
503 "device");
504 if (result) {
505 printk(KERN_ERR PREFIX "Create sysfs link\n");
506 goto err_remove_sysfs_thermal;
507 }
508
509 return 0;
510
511 err_remove_sysfs_thermal:
512 sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
513 err_thermal_unregister:
514 thermal_cooling_device_unregister(pr->cdev);
515 err_power_exit:
516 acpi_processor_power_exit(pr, device);
517
518 return result;
519 }
520
521 /*
522 * Do not put anything in here which needs the core to be online.
523 * For example MSR access or setting up things which check for cpuinfo_x86
524 * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.
525 * Such things have to be put in and set up above in acpi_processor_start()
526 */
acpi_processor_add(struct acpi_device * device)527 static int __cpuinit acpi_processor_add(struct acpi_device *device)
528 {
529 struct acpi_processor *pr = NULL;
530 int result = 0;
531 struct device *dev;
532
533 pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
534 if (!pr)
535 return -ENOMEM;
536
537 if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) {
538 kfree(pr);
539 return -ENOMEM;
540 }
541
542 pr->handle = device->handle;
543 strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
544 strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
545 device->driver_data = pr;
546
547 result = acpi_processor_get_info(device);
548 if (result) {
549 /* Processor is physically not present */
550 return 0;
551 }
552
553 #ifdef CONFIG_SMP
554 if (pr->id >= setup_max_cpus && pr->id != 0)
555 return 0;
556 #endif
557
558 BUG_ON((pr->id >= nr_cpu_ids) || (pr->id < 0));
559
560 /*
561 * Buggy BIOS check
562 * ACPI id of processors can be reported wrongly by the BIOS.
563 * Don't trust it blindly
564 */
565 if (per_cpu(processor_device_array, pr->id) != NULL &&
566 per_cpu(processor_device_array, pr->id) != device) {
567 printk(KERN_WARNING "BIOS reported wrong ACPI id "
568 "for the processor\n");
569 result = -ENODEV;
570 goto err_free_cpumask;
571 }
572 per_cpu(processor_device_array, pr->id) = device;
573
574 per_cpu(processors, pr->id) = pr;
575
576 dev = get_cpu_device(pr->id);
577 if (sysfs_create_link(&device->dev.kobj, &dev->kobj, "sysdev")) {
578 result = -EFAULT;
579 goto err_free_cpumask;
580 }
581
582 /*
583 * Do not start hotplugged CPUs now, but when they
584 * are onlined the first time
585 */
586 if (pr->flags.need_hotplug_init)
587 return 0;
588
589 result = acpi_processor_start(pr);
590 if (result)
591 goto err_remove_sysfs;
592
593 return 0;
594
595 err_remove_sysfs:
596 sysfs_remove_link(&device->dev.kobj, "sysdev");
597 err_free_cpumask:
598 free_cpumask_var(pr->throttling.shared_cpu_map);
599
600 return result;
601 }
602
acpi_processor_remove(struct acpi_device * device,int type)603 static int acpi_processor_remove(struct acpi_device *device, int type)
604 {
605 struct acpi_processor *pr = NULL;
606
607
608 if (!device || !acpi_driver_data(device))
609 return -EINVAL;
610
611 pr = acpi_driver_data(device);
612
613 if (pr->id >= nr_cpu_ids)
614 goto free;
615
616 if (type == ACPI_BUS_REMOVAL_EJECT) {
617 if (acpi_processor_handle_eject(pr))
618 return -EINVAL;
619 }
620
621 acpi_processor_power_exit(pr, device);
622
623 sysfs_remove_link(&device->dev.kobj, "sysdev");
624
625 if (pr->cdev) {
626 sysfs_remove_link(&device->dev.kobj, "thermal_cooling");
627 sysfs_remove_link(&pr->cdev->device.kobj, "device");
628 thermal_cooling_device_unregister(pr->cdev);
629 pr->cdev = NULL;
630 }
631
632 per_cpu(processors, pr->id) = NULL;
633 per_cpu(processor_device_array, pr->id) = NULL;
634
635 free:
636 free_cpumask_var(pr->throttling.shared_cpu_map);
637 kfree(pr);
638
639 return 0;
640 }
641
642 #ifdef CONFIG_ACPI_HOTPLUG_CPU
643 /****************************************************************************
644 * Acpi processor hotplug support *
645 ****************************************************************************/
646
is_processor_present(acpi_handle handle)647 static int is_processor_present(acpi_handle handle)
648 {
649 acpi_status status;
650 unsigned long long sta = 0;
651
652
653 status = acpi_evaluate_integer(handle, "_STA", NULL, &sta);
654
655 if (ACPI_SUCCESS(status) && (sta & ACPI_STA_DEVICE_PRESENT))
656 return 1;
657
658 /*
659 * _STA is mandatory for a processor that supports hot plug
660 */
661 if (status == AE_NOT_FOUND)
662 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
663 "Processor does not support hot plug\n"));
664 else
665 ACPI_EXCEPTION((AE_INFO, status,
666 "Processor Device is not present"));
667 return 0;
668 }
669
670 static
acpi_processor_device_add(acpi_handle handle,struct acpi_device ** device)671 int acpi_processor_device_add(acpi_handle handle, struct acpi_device **device)
672 {
673 acpi_handle phandle;
674 struct acpi_device *pdev;
675
676
677 if (acpi_get_parent(handle, &phandle)) {
678 return -ENODEV;
679 }
680
681 if (acpi_bus_get_device(phandle, &pdev)) {
682 return -ENODEV;
683 }
684
685 if (acpi_bus_add(device, pdev, handle, ACPI_BUS_TYPE_PROCESSOR)) {
686 return -ENODEV;
687 }
688
689 return 0;
690 }
691
acpi_processor_hotplug_notify(acpi_handle handle,u32 event,void * data)692 static void acpi_processor_hotplug_notify(acpi_handle handle,
693 u32 event, void *data)
694 {
695 struct acpi_processor *pr;
696 struct acpi_device *device = NULL;
697 int result;
698
699
700 switch (event) {
701 case ACPI_NOTIFY_BUS_CHECK:
702 case ACPI_NOTIFY_DEVICE_CHECK:
703 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
704 "Processor driver received %s event\n",
705 (event == ACPI_NOTIFY_BUS_CHECK) ?
706 "ACPI_NOTIFY_BUS_CHECK" : "ACPI_NOTIFY_DEVICE_CHECK"));
707
708 if (!is_processor_present(handle))
709 break;
710
711 if (acpi_bus_get_device(handle, &device)) {
712 result = acpi_processor_device_add(handle, &device);
713 if (result)
714 printk(KERN_ERR PREFIX
715 "Unable to add the device\n");
716 break;
717 }
718 break;
719 case ACPI_NOTIFY_EJECT_REQUEST:
720 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
721 "received ACPI_NOTIFY_EJECT_REQUEST\n"));
722
723 if (acpi_bus_get_device(handle, &device)) {
724 printk(KERN_ERR PREFIX
725 "Device don't exist, dropping EJECT\n");
726 break;
727 }
728 pr = acpi_driver_data(device);
729 if (!pr) {
730 printk(KERN_ERR PREFIX
731 "Driver data is NULL, dropping EJECT\n");
732 return;
733 }
734 break;
735 default:
736 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
737 "Unsupported event [0x%x]\n", event));
738 break;
739 }
740
741 return;
742 }
743
744 static acpi_status
processor_walk_namespace_cb(acpi_handle handle,u32 lvl,void * context,void ** rv)745 processor_walk_namespace_cb(acpi_handle handle,
746 u32 lvl, void *context, void **rv)
747 {
748 acpi_status status;
749 int *action = context;
750 acpi_object_type type = 0;
751
752 status = acpi_get_type(handle, &type);
753 if (ACPI_FAILURE(status))
754 return (AE_OK);
755
756 if (type != ACPI_TYPE_PROCESSOR)
757 return (AE_OK);
758
759 switch (*action) {
760 case INSTALL_NOTIFY_HANDLER:
761 acpi_install_notify_handler(handle,
762 ACPI_SYSTEM_NOTIFY,
763 acpi_processor_hotplug_notify,
764 NULL);
765 break;
766 case UNINSTALL_NOTIFY_HANDLER:
767 acpi_remove_notify_handler(handle,
768 ACPI_SYSTEM_NOTIFY,
769 acpi_processor_hotplug_notify);
770 break;
771 default:
772 break;
773 }
774
775 return (AE_OK);
776 }
777
acpi_processor_hotadd_init(struct acpi_processor * pr)778 static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr)
779 {
780 acpi_handle handle = pr->handle;
781
782 if (!is_processor_present(handle)) {
783 return AE_ERROR;
784 }
785
786 if (acpi_map_lsapic(handle, &pr->id))
787 return AE_ERROR;
788
789 if (arch_register_cpu(pr->id)) {
790 acpi_unmap_lsapic(pr->id);
791 return AE_ERROR;
792 }
793
794 /* CPU got hot-plugged, but cpu_data is not initialized yet
795 * Set flag to delay cpu_idle/throttling initialization
796 * in:
797 * acpi_processor_add()
798 * acpi_processor_get_info()
799 * and do it when the CPU gets online the first time
800 * TBD: Cleanup above functions and try to do this more elegant.
801 */
802 printk(KERN_INFO "CPU %d got hotplugged\n", pr->id);
803 pr->flags.need_hotplug_init = 1;
804
805 return AE_OK;
806 }
807
acpi_processor_handle_eject(struct acpi_processor * pr)808 static int acpi_processor_handle_eject(struct acpi_processor *pr)
809 {
810 if (cpu_online(pr->id))
811 cpu_down(pr->id);
812
813 arch_unregister_cpu(pr->id);
814 acpi_unmap_lsapic(pr->id);
815 return (0);
816 }
817 #else
acpi_processor_hotadd_init(struct acpi_processor * pr)818 static acpi_status acpi_processor_hotadd_init(struct acpi_processor *pr)
819 {
820 return AE_ERROR;
821 }
acpi_processor_handle_eject(struct acpi_processor * pr)822 static int acpi_processor_handle_eject(struct acpi_processor *pr)
823 {
824 return (-EINVAL);
825 }
826 #endif
827
828 static
acpi_processor_install_hotplug_notify(void)829 void acpi_processor_install_hotplug_notify(void)
830 {
831 #ifdef CONFIG_ACPI_HOTPLUG_CPU
832 int action = INSTALL_NOTIFY_HANDLER;
833 acpi_walk_namespace(ACPI_TYPE_PROCESSOR,
834 ACPI_ROOT_OBJECT,
835 ACPI_UINT32_MAX,
836 processor_walk_namespace_cb, NULL, &action, NULL);
837 #endif
838 register_hotcpu_notifier(&acpi_cpu_notifier);
839 }
840
841 static
acpi_processor_uninstall_hotplug_notify(void)842 void acpi_processor_uninstall_hotplug_notify(void)
843 {
844 #ifdef CONFIG_ACPI_HOTPLUG_CPU
845 int action = UNINSTALL_NOTIFY_HANDLER;
846 acpi_walk_namespace(ACPI_TYPE_PROCESSOR,
847 ACPI_ROOT_OBJECT,
848 ACPI_UINT32_MAX,
849 processor_walk_namespace_cb, NULL, &action, NULL);
850 #endif
851 unregister_hotcpu_notifier(&acpi_cpu_notifier);
852 }
853
854 /*
855 * We keep the driver loaded even when ACPI is not running.
856 * This is needed for the powernow-k8 driver, that works even without
857 * ACPI, but needs symbols from this driver
858 */
859
acpi_processor_init(void)860 static int __init acpi_processor_init(void)
861 {
862 int result = 0;
863
864 if (acpi_disabled)
865 return 0;
866
867 memset(&errata, 0, sizeof(errata));
868
869 result = acpi_bus_register_driver(&acpi_processor_driver);
870 if (result < 0)
871 return result;
872
873 acpi_processor_install_hotplug_notify();
874
875 acpi_thermal_cpufreq_init();
876
877 acpi_processor_ppc_init();
878
879 acpi_processor_throttling_init();
880
881 return 0;
882 }
883
acpi_processor_exit(void)884 static void __exit acpi_processor_exit(void)
885 {
886 if (acpi_disabled)
887 return;
888
889 acpi_processor_ppc_exit();
890
891 acpi_thermal_cpufreq_exit();
892
893 acpi_processor_uninstall_hotplug_notify();
894
895 acpi_bus_unregister_driver(&acpi_processor_driver);
896
897 return;
898 }
899
900 module_init(acpi_processor_init);
901 module_exit(acpi_processor_exit);
902
903 MODULE_ALIAS("processor");
904