summaryrefslogtreecommitdiff
path: root/drivers/acpi/acpi_processor.c
blob: 58f335ca2e75f9cc3ca47eb7ef2140fb010ee7e4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
/*
 * acpi_processor.c - ACPI processor enumeration support
 *
 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
 * Copyright (C) 2004       Dominik Brodowski <linux@brodo.de>
 * Copyright (C) 2004  Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
 * Copyright (C) 2013, Intel Corporation
 *                     Rafael J. Wysocki <rafael.j.wysocki@intel.com>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 as published
 * by the Free Software Foundation.
 */

#include <linux/acpi.h>
#include <linux/device.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>

#include <acpi/processor.h>

#include <asm/cpu.h>

#include "internal.h"

#define _COMPONENT	ACPI_PROCESSOR_COMPONENT

ACPI_MODULE_NAME("processor");

DEFINE_PER_CPU(struct acpi_processor *, processors);
EXPORT_PER_CPU_SYMBOL(processors);

/* --------------------------------------------------------------------------
                                Errata Handling
   -------------------------------------------------------------------------- */

struct acpi_processor_errata errata __read_mostly;
EXPORT_SYMBOL_GPL(errata);

static int acpi_processor_errata_piix4(struct pci_dev *dev)
{
	u8 value1 = 0;
	u8 value2 = 0;


	if (!dev)
		return -EINVAL;

	/*
	 * Note that 'dev' references the PIIX4 ACPI Controller.
	 */

	switch (dev->revision) {
	case 0:
		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 A-step\n"));
		break;
	case 1:
		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4 B-step\n"));
		break;
	case 2:
		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4E\n"));
		break;
	case 3:
		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found PIIX4M\n"));
		break;
	default:
		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found unknown PIIX4\n"));
		break;
	}

	switch (dev->revision) {

	case 0:		/* PIIX4 A-step */
	case 1:		/* PIIX4 B-step */
		/*
		 * See specification changes #13 ("Manual Throttle Duty Cycle")
		 * and #14 ("Enabling and Disabling Manual Throttle"), plus
		 * erratum #5 ("STPCLK# Deassertion Time") from the January
		 * 2002 PIIX4 specification update.  Applies to only older
		 * PIIX4 models.
		 */
		errata.piix4.throttle = 1;

	case 2:		/* PIIX4E */
	case 3:		/* PIIX4M */
		/*
		 * See erratum #18 ("C3 Power State/BMIDE and Type-F DMA
		 * Livelock") from the January 2002 PIIX4 specification update.
		 * Applies to all PIIX4 models.
		 */

		/*
		 * BM-IDE
		 * ------
		 * Find the PIIX4 IDE Controller and get the Bus Master IDE
		 * Status register address.  We'll use this later to read
		 * each IDE controller's DMA status to make sure we catch all
		 * DMA activity.
		 */
		dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
				     PCI_DEVICE_ID_INTEL_82371AB,
				     PCI_ANY_ID, PCI_ANY_ID, NULL);
		if (dev) {
			errata.piix4.bmisx = pci_resource_start(dev, 4);
			pci_dev_put(dev);
		}

		/*
		 * Type-F DMA
		 * ----------
		 * Find the PIIX4 ISA Controller and read the Motherboard
		 * DMA controller's status to see if Type-F (Fast) DMA mode
		 * is enabled (bit 7) on either channel.  Note that we'll
		 * disable C3 support if this is enabled, as some legacy
		 * devices won't operate well if fast DMA is disabled.
		 */
		dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
				     PCI_DEVICE_ID_INTEL_82371AB_0,
				     PCI_ANY_ID, PCI_ANY_ID, NULL);
		if (dev) {
			pci_read_config_byte(dev, 0x76, &value1);
			pci_read_config_byte(dev, 0x77, &value2);
			if ((value1 & 0x80) || (value2 & 0x80))
				errata.piix4.fdma = 1;
			pci_dev_put(dev);
		}

		break;
	}

	if (errata.piix4.bmisx)
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "Bus master activity detection (BM-IDE) erratum enabled\n"));
	if (errata.piix4.fdma)
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "Type-F DMA livelock erratum (C3 disabled)\n"));

	return 0;
}

static int acpi_processor_errata(void)
{
	int result = 0;
	struct pci_dev *dev = NULL;

	/*
	 * PIIX4
	 */
	dev = pci_get_subsys(PCI_VENDOR_ID_INTEL,
			     PCI_DEVICE_ID_INTEL_82371AB_3, PCI_ANY_ID,
			     PCI_ANY_ID, NULL);
	if (dev) {
		result = acpi_processor_errata_piix4(dev);
		pci_dev_put(dev);
	}

	return result;
}

/* --------------------------------------------------------------------------
                                Initialization
   -------------------------------------------------------------------------- */

#ifdef CONFIG_ACPI_HOTPLUG_CPU
static int acpi_processor_hotadd_init(struct acpi_processor *pr)
{
	unsigned long long sta;
	acpi_status status;
	int ret;

	if (pr->phys_id == PHYS_CPUID_INVALID)
		return -ENODEV;

	status = acpi_evaluate_integer(pr->handle, "_STA", NULL, &sta);
	if (ACPI_FAILURE(status) || !(sta & ACPI_STA_DEVICE_PRESENT))
		return -ENODEV;

	cpu_maps_update_begin();
	cpu_hotplug_begin();

	ret = acpi_map_cpu(pr->handle, pr->phys_id, &pr->id);
	if (ret)
		goto out;

	ret = arch_register_cpu(pr->id);
	if (ret) {
		acpi_unmap_cpu(pr->id);
		goto out;
	}

	/*
	 * CPU got hot-added, but cpu_data is not initialized yet.  Set a flag
	 * to delay cpu_idle/throttling initialization and do it when the CPU
	 * gets online for the first time.
	 */
	pr_info("CPU%d has been hot-added\n", pr->id);
	pr->flags.need_hotplug_init = 1;

out:
	cpu_hotplug_done();
	cpu_maps_update_done();
	return ret;
}
#else
static inline int acpi_processor_hotadd_init(struct acpi_processor *pr)
{
	return -ENODEV;
}
#endif /* CONFIG_ACPI_HOTPLUG_CPU */

static int acpi_processor_get_info(struct acpi_device *device)
{
	union acpi_object object = { 0 };
	struct acpi_buffer buffer = { sizeof(union acpi_object), &object };
	struct acpi_processor *pr = acpi_driver_data(device);
	phys_cpuid_t phys_id;
	int cpu_index, device_declaration = 0;
	acpi_status status = AE_OK;
	static int cpu0_initialized;
	unsigned long long value;

	acpi_processor_errata();

	/*
	 * Check to see if we have bus mastering arbitration control.  This
	 * is required for proper C3 usage (to maintain cache coherency).
	 */
	if (acpi_gbl_FADT.pm2_control_block && acpi_gbl_FADT.pm2_control_length) {
		pr->flags.bm_control = 1;
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "Bus mastering arbitration control present\n"));
	} else
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "No bus mastering arbitration control\n"));

	if (!strcmp(acpi_device_hid(device), ACPI_PROCESSOR_OBJECT_HID)) {
		/* Declared with "Processor" statement; match ProcessorID */
		status = acpi_evaluate_object(pr->handle, NULL, NULL, &buffer);
		if (ACPI_FAILURE(status)) {
			dev_err(&device->dev,
				"Failed to evaluate processor object (0x%x)\n",
				status);
			return -ENODEV;
		}

		pr->acpi_id = object.processor.proc_id;
	} else {
		/*
		 * Declared with "Device" statement; match _UID.
		 * Note that we don't handle string _UIDs yet.
		 */
		status = acpi_evaluate_integer(pr->handle, METHOD_NAME__UID,
						NULL, &value);
		if (ACPI_FAILURE(status)) {
			dev_err(&device->dev,
				"Failed to evaluate processor _UID (0x%x)\n",
				status);
			return -ENODEV;
		}
		device_declaration = 1;
		pr->acpi_id = value;
	}

	phys_id = acpi_get_phys_id(pr->handle, device_declaration, pr->acpi_id);
	if (phys_id == PHYS_CPUID_INVALID)
		acpi_handle_debug(pr->handle, "failed to get CPU physical ID.\n");
	pr->phys_id = phys_id;

	cpu_index = acpi_map_cpuid(pr->phys_id, pr->acpi_id);
	if (!cpu0_initialized && !acpi_has_cpu_in_madt()) {
		cpu0_initialized = 1;
		/*
		 * Handle UP system running SMP kernel, with no CPU
		 * entry in MADT
		 */
		if ((cpu_index == -1) && (num_online_cpus() == 1))
			cpu_index = 0;
	}
	pr->id = cpu_index;

	/*
	 *  Extra Processor objects may be enumerated on MP systems with
	 *  less than the max # of CPUs. They should be ignored _iff
	 *  they are physically not present.
	 */
	if (pr->id == -1) {
		int ret = acpi_processor_hotadd_init(pr);
		if (ret)
			return ret;
	}

	/*
	 * On some boxes several processors use the same processor bus id.
	 * But they are located in different scope. For example:
	 * \_SB.SCK0.CPU0
	 * \_SB.SCK1.CPU0
	 * Rename the processor device bus id. And the new bus id will be
	 * generated as the following format:
	 * CPU+CPU ID.
	 */
	sprintf(acpi_device_bid(device), "CPU%X", pr->id);
	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Processor [%d:%d]\n", pr->id,
			  pr->acpi_id));

	if (!object.processor.pblk_address)
		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No PBLK (NULL address)\n"));
	else if (object.processor.pblk_length != 6)
		dev_err(&device->dev, "Invalid PBLK length [%d]\n",
			    object.processor.pblk_length);
	else {
		pr->throttling.address = object.processor.pblk_address;
		pr->throttling.duty_offset = acpi_gbl_FADT.duty_offset;
		pr->throttling.duty_width = acpi_gbl_FADT.duty_width;

		pr->pblk = object.processor.pblk_address;

		/*
		 * We don't care about error returns - we just try to mark
		 * these reserved so that nobody else is confused into thinking
		 * that this region might be unused..
		 *
		 * (In particular, allocating the IO range for Cardbus)
		 */
		request_region(pr->throttling.address, 6, "ACPI CPU throttle");
	}

	/*
	 * If ACPI describes a slot number for this CPU, we can use it to
	 * ensure we get the right value in the "physical id" field
	 * of /proc/cpuinfo
	 */
	status = acpi_evaluate_integer(pr->handle, "_SUN", NULL, &value);
	if (ACPI_SUCCESS(status))
		arch_fix_phys_package_id(pr->id, value);

	return 0;
}

/*
 * Do not put anything in here which needs the core to be online.
 * For example MSR access or setting up things which check for cpuinfo_x86
 * (cpu_data(cpu)) values, like CPU feature flags, family, model, etc.
 * Such things have to be put in and set up by the processor driver's .probe().
 */
static DEFINE_PER_CPU(void *, processor_device_array);

static int acpi_processor_add(struct acpi_device *device,
					const struct acpi_device_id *id)
{
	struct acpi_processor *pr;
	struct device *dev;
	int result = 0;

	pr = kzalloc(sizeof(struct acpi_processor), GFP_KERNEL);
	if (!pr)
		return -ENOMEM;

	if (!zalloc_cpumask_var(&pr->throttling.shared_cpu_map, GFP_KERNEL)) {
		result = -ENOMEM;
		goto err_free_pr;
	}

	pr->handle = device->handle;
	strcpy(acpi_device_name(device), ACPI_PROCESSOR_DEVICE_NAME);
	strcpy(acpi_device_class(device), ACPI_PROCESSOR_CLASS);
	device->driver_data = pr;

	result = acpi_processor_get_info(device);
	if (result) /* Processor is not physically present or unavailable */
		return 0;

#ifdef CONFIG_SMP
	if (pr->id >= setup_max_cpus && pr->id != 0)
		return 0;
#endif

	BUG_ON(pr->id >= nr_cpu_ids);

	/*
	 * Buggy BIOS check.
	 * ACPI id of processors can be reported wrongly by the BIOS.
	 * Don't trust it blindly
	 */
	if (per_cpu(processor_device_array, pr->id) != NULL &&
	    per_cpu(processor_device_array, pr->id) != device) {
		dev_warn(&device->dev,
			"BIOS reported wrong ACPI id %d for the processor\n",
			pr->id);
		/* Give up, but do not abort the namespace scan. */
		goto err;
	}
	/*
	 * processor_device_array is not cleared on errors to allow buggy BIOS
	 * checks.
	 */
	per_cpu(processor_device_array, pr->id) = device;
	per_cpu(processors, pr->id) = pr;

	dev = get_cpu_device(pr->id);
	if (!dev) {
		result = -ENODEV;
		goto err;
	}

	result = acpi_bind_one(dev, device);
	if (result)
		goto err;

	pr->dev = dev;

	/* Trigger the processor driver's .probe() if present. */
	if (device_attach(dev) >= 0)
		return 1;

	dev_err(dev, "Processor driver could not be attached\n");
	acpi_unbind_one(dev);

 err:
	free_cpumask_var(pr->throttling.shared_cpu_map);
	device->driver_data = NULL;
	per_cpu(processors, pr->id) = NULL;
 err_free_pr:
	kfree(pr);
	return result;
}

#ifdef CONFIG_ACPI_HOTPLUG_CPU
/* --------------------------------------------------------------------------
                                    Removal
   -------------------------------------------------------------------------- */

static void acpi_processor_remove(struct acpi_device *device)
{
	struct acpi_processor *pr;

	if (!device || !acpi_driver_data(device))
		return;

	pr = acpi_driver_data(device);
	if (pr->id >= nr_cpu_ids)
		goto out;

	/*
	 * The only reason why we ever get here is CPU hot-removal.  The CPU is
	 * already offline and the ACPI device removal locking prevents it from
	 * being put back online at this point.
	 *
	 * Unbind the driver from the processor device and detach it from the
	 * ACPI companion object.
	 */
	device_release_driver(pr->dev);
	acpi_unbind_one(pr->dev);

	/* Clean up. */
	per_cpu(processor_device_array, pr->id) = NULL;
	per_cpu(processors, pr->id) = NULL;

	cpu_maps_update_begin();
	cpu_hotplug_begin();

	/* Remove the CPU. */
	arch_unregister_cpu(pr->id);
	acpi_unmap_cpu(pr->id);

	cpu_hotplug_done();
	cpu_maps_update_done();

	try_offline_node(cpu_to_node(pr->id));

 out:
	free_cpumask_var(pr->throttling.shared_cpu_map);
	kfree(pr);
}
#endif /* CONFIG_ACPI_HOTPLUG_CPU */

/*
 * The following ACPI IDs are known to be suitable for representing as
 * processor devices.
 */
static const struct acpi_device_id processor_device_ids[] = {

	{ ACPI_PROCESSOR_OBJECT_HID, },
	{ ACPI_PROCESSOR_DEVICE_HID, },

	{ }
};

static struct acpi_scan_handler __refdata processor_handler = {
	.ids = processor_device_ids,
	.attach = acpi_processor_add,
#ifdef CONFIG_ACPI_HOTPLUG_CPU
	.detach = acpi_processor_remove,
#endif
	.hotplug = {
		.enabled = true,
	},
};

void __init acpi_processor_init(void)
{
	acpi_scan_add_handler_with_hotplug(&processor_handler, "processor");
}