aboutsummaryrefslogtreecommitdiff
path: root/drivers/acpi/processor_perflib.c
blob: f36db22ce1aeb9b745ee815f6266779f31e98945 (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
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
/*
 * processor_perflib.c - ACPI Processor P-States Library ($Revision: 71 $)
 *
 *  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>
 *  			- Added processor hotplug support
 *
 *
 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or (at
 *  your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful, but
 *  WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
 *
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/cpufreq.h>

#ifdef CONFIG_X86_ACPI_CPUFREQ_PROC_INTF
#include <linux/proc_fs.h>
#include <linux/seq_file.h>

#include <asm/uaccess.h>
#endif

#include <acpi/acpi_bus.h>
#include <acpi/processor.h>

#define ACPI_PROCESSOR_COMPONENT	0x01000000
#define ACPI_PROCESSOR_CLASS		"processor"
#define ACPI_PROCESSOR_DRIVER_NAME	"ACPI Processor Driver"
#define ACPI_PROCESSOR_FILE_PERFORMANCE	"performance"
#define _COMPONENT		ACPI_PROCESSOR_COMPONENT
ACPI_MODULE_NAME("acpi_processor")

static DECLARE_MUTEX(performance_sem);

/*
 * _PPC support is implemented as a CPUfreq policy notifier:
 * This means each time a CPUfreq driver registered also with
 * the ACPI core is asked to change the speed policy, the maximum
 * value is adjusted so that it is within the platform limit.
 *
 * Also, when a new platform limit value is detected, the CPUfreq
 * policy is adjusted accordingly.
 */

#define PPC_REGISTERED   1
#define PPC_IN_USE       2

static int acpi_processor_ppc_status = 0;

static int acpi_processor_ppc_notifier(struct notifier_block *nb,
				       unsigned long event, void *data)
{
	struct cpufreq_policy *policy = data;
	struct acpi_processor *pr;
	unsigned int ppc = 0;

	down(&performance_sem);

	if (event != CPUFREQ_INCOMPATIBLE)
		goto out;

	pr = processors[policy->cpu];
	if (!pr || !pr->performance)
		goto out;

	ppc = (unsigned int)pr->performance_platform_limit;
	if (!ppc)
		goto out;

	if (ppc > pr->performance->state_count)
		goto out;

	cpufreq_verify_within_limits(policy, 0,
				     pr->performance->states[ppc].
				     core_frequency * 1000);

      out:
	up(&performance_sem);

	return 0;
}

static struct notifier_block acpi_ppc_notifier_block = {
	.notifier_call = acpi_processor_ppc_notifier,
};

static int acpi_processor_get_platform_limit(struct acpi_processor *pr)
{
	acpi_status status = 0;
	unsigned long ppc = 0;

	ACPI_FUNCTION_TRACE("acpi_processor_get_platform_limit");

	if (!pr)
		return_VALUE(-EINVAL);

	/*
	 * _PPC indicates the maximum state currently supported by the platform
	 * (e.g. 0 = states 0..n; 1 = states 1..n; etc.
	 */
	status = acpi_evaluate_integer(pr->handle, "_PPC", NULL, &ppc);

	if (status != AE_NOT_FOUND)
		acpi_processor_ppc_status |= PPC_IN_USE;

	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _PPC\n"));
		return_VALUE(-ENODEV);
	}

	pr->performance_platform_limit = (int)ppc;

	return_VALUE(0);
}

int acpi_processor_ppc_has_changed(struct acpi_processor *pr)
{
	int ret = acpi_processor_get_platform_limit(pr);
	if (ret < 0)
		return (ret);
	else
		return cpufreq_update_policy(pr->id);
}

void acpi_processor_ppc_init(void)
{
	if (!cpufreq_register_notifier
	    (&acpi_ppc_notifier_block, CPUFREQ_POLICY_NOTIFIER))
		acpi_processor_ppc_status |= PPC_REGISTERED;
	else
		printk(KERN_DEBUG
		       "Warning: Processor Platform Limit not supported.\n");
}

void acpi_processor_ppc_exit(void)
{
	if (acpi_processor_ppc_status & PPC_REGISTERED)
		cpufreq_unregister_notifier(&acpi_ppc_notifier_block,
					    CPUFREQ_POLICY_NOTIFIER);

	acpi_processor_ppc_status &= ~PPC_REGISTERED;
}

static int acpi_processor_get_performance_control(struct acpi_processor *pr)
{
	int result = 0;
	acpi_status status = 0;
	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
	union acpi_object *pct = NULL;
	union acpi_object obj = { 0 };

	ACPI_FUNCTION_TRACE("acpi_processor_get_performance_control");

	status = acpi_evaluate_object(pr->handle, "_PCT", NULL, &buffer);
	if (ACPI_FAILURE(status)) {
		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _PCT\n"));
		return_VALUE(-ENODEV);
	}

	pct = (union acpi_object *)buffer.pointer;
	if (!pct || (pct->type != ACPI_TYPE_PACKAGE)
	    || (pct->package.count != 2)) {
		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PCT data\n"));
		result = -EFAULT;
		goto end;
	}

	/*
	 * control_register
	 */

	obj = pct->package.elements[0];

	if ((obj.type != ACPI_TYPE_BUFFER)
	    || (obj.buffer.length < sizeof(struct acpi_pct_register))
	    || (obj.buffer.pointer == NULL)) {
		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
				  "Invalid _PCT data (control_register)\n"));
		result = -EFAULT;
		goto end;
	}
	memcpy(&pr->performance->control_register, obj.buffer.pointer,
	       sizeof(struct acpi_pct_register));

	/*
	 * status_register
	 */

	obj = pct->package.elements[1];

	if ((obj.type != ACPI_TYPE_BUFFER)
	    || (obj.buffer.length < sizeof(struct acpi_pct_register))
	    || (obj.buffer.pointer == NULL)) {
		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
				  "Invalid _PCT data (status_register)\n"));
		result = -EFAULT;
		goto end;
	}

	memcpy(&pr->performance->status_register, obj.buffer.pointer,
	       sizeof(struct acpi_pct_register));

      end:
	acpi_os_free(buffer.pointer);

	return_VALUE(result);
}

static int acpi_processor_get_performance_states(struct acpi_processor *pr)
{
	int result = 0;
	acpi_status status = AE_OK;
	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
	struct acpi_buffer format = { sizeof("NNNNNN"), "NNNNNN" };
	struct acpi_buffer state = { 0, NULL };
	union acpi_object *pss = NULL;
	int i;

	ACPI_FUNCTION_TRACE("acpi_processor_get_performance_states");

	status = acpi_evaluate_object(pr->handle, "_PSS", NULL, &buffer);
	if (ACPI_FAILURE(status)) {
		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _PSS\n"));
		return_VALUE(-ENODEV);
	}

	pss = (union acpi_object *)buffer.pointer;
	if (!pss || (pss->type != ACPI_TYPE_PACKAGE)) {
		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid _PSS data\n"));
		result = -EFAULT;
		goto end;
	}

	ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %d performance states\n",
			  pss->package.count));

	pr->performance->state_count = pss->package.count;
	pr->performance->states =
	    kmalloc(sizeof(struct acpi_processor_px) * pss->package.count,
		    GFP_KERNEL);
	if (!pr->performance->states) {
		result = -ENOMEM;
		goto end;
	}

	for (i = 0; i < pr->performance->state_count; i++) {

		struct acpi_processor_px *px = &(pr->performance->states[i]);

		state.length = sizeof(struct acpi_processor_px);
		state.pointer = px;

		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Extracting state %d\n", i));

		status = acpi_extract_package(&(pss->package.elements[i]),
					      &format, &state);
		if (ACPI_FAILURE(status)) {
			ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
					  "Invalid _PSS data\n"));
			result = -EFAULT;
			kfree(pr->performance->states);
			goto end;
		}

		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "State [%d]: core_frequency[%d] power[%d] transition_latency[%d] bus_master_latency[%d] control[0x%x] status[0x%x]\n",
				  i,
				  (u32) px->core_frequency,
				  (u32) px->power,
				  (u32) px->transition_latency,
				  (u32) px->bus_master_latency,
				  (u32) px->control, (u32) px->status));

		if (!px->core_frequency) {
			ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
					  "Invalid _PSS data: freq is zero\n"));
			result = -EFAULT;
			kfree(pr->performance->states);
			goto end;
		}
	}

      end:
	acpi_os_free(buffer.pointer);

	return_VALUE(result);
}

static int acpi_processor_get_performance_info(struct acpi_processor *pr)
{
	int result = 0;
	acpi_status status = AE_OK;
	acpi_handle handle = NULL;

	ACPI_FUNCTION_TRACE("acpi_processor_get_performance_info");

	if (!pr || !pr->performance || !pr->handle)
		return_VALUE(-EINVAL);

	status = acpi_get_handle(pr->handle, "_PCT", &handle);
	if (ACPI_FAILURE(status)) {
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "ACPI-based processor performance control unavailable\n"));
		return_VALUE(-ENODEV);
	}

	result = acpi_processor_get_performance_control(pr);
	if (result)
		return_VALUE(result);

	result = acpi_processor_get_performance_states(pr);
	if (result)
		return_VALUE(result);

	result = acpi_processor_get_platform_limit(pr);
	if (result)
		return_VALUE(result);

	return_VALUE(0);
}

int acpi_processor_notify_smm(struct module *calling_module)
{
	acpi_status status;
	static int is_done = 0;

	ACPI_FUNCTION_TRACE("acpi_processor_notify_smm");

	if (!(acpi_processor_ppc_status & PPC_REGISTERED))
		return_VALUE(-EBUSY);

	if (!try_module_get(calling_module))
		return_VALUE(-EINVAL);

	/* is_done is set to negative if an error occured,
	 * and to postitive if _no_ error occured, but SMM
	 * was already notified. This avoids double notification
	 * which might lead to unexpected results...
	 */
	if (is_done > 0) {
		module_put(calling_module);
		return_VALUE(0);
	} else if (is_done < 0) {
		module_put(calling_module);
		return_VALUE(is_done);
	}

	is_done = -EIO;

	/* Can't write pstate_cnt to smi_cmd if either value is zero */
	if ((!acpi_fadt.smi_cmd) || (!acpi_fadt.pstate_cnt)) {
		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No SMI port or pstate_cnt\n"));
		module_put(calling_module);
		return_VALUE(0);
	}

	ACPI_DEBUG_PRINT((ACPI_DB_INFO,
			  "Writing pstate_cnt [0x%x] to smi_cmd [0x%x]\n",
			  acpi_fadt.pstate_cnt, acpi_fadt.smi_cmd));

	/* FADT v1 doesn't support pstate_cnt, many BIOS vendors use
	 * it anyway, so we need to support it... */
	if (acpi_fadt_is_v1) {
		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
				  "Using v1.0 FADT reserved value for pstate_cnt\n"));
	}

	status = acpi_os_write_port(acpi_fadt.smi_cmd,
				    (u32) acpi_fadt.pstate_cnt, 8);
	if (ACPI_FAILURE(status)) {
		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
				  "Failed to write pstate_cnt [0x%x] to "
				  "smi_cmd [0x%x]\n", acpi_fadt.pstate_cnt,
				  acpi_fadt.smi_cmd));
		module_put(calling_module);
		return_VALUE(status);
	}

	/* Success. If there's no _PPC, we need to fear nothing, so
	 * we can allow the cpufreq driver to be rmmod'ed. */
	is_done = 1;

	if (!(acpi_processor_ppc_status & PPC_IN_USE))
		module_put(calling_module);

	return_VALUE(0);
}

EXPORT_SYMBOL(acpi_processor_notify_smm);

#ifdef CONFIG_X86_ACPI_CPUFREQ_PROC_INTF
/* /proc/acpi/processor/../performance interface (DEPRECATED) */

static int acpi_processor_perf_open_fs(struct inode *inode, struct file *file);
static struct file_operations acpi_processor_perf_fops = {
	.open = acpi_processor_perf_open_fs,
	.read = seq_read,
	.llseek = seq_lseek,
	.release = single_release,
};

static int acpi_processor_perf_seq_show(struct seq_file *seq, void *offset)
{
	struct acpi_processor *pr = (struct acpi_processor *)seq->private;
	int i;

	ACPI_FUNCTION_TRACE("acpi_processor_perf_seq_show");

	if (!pr)
		goto end;

	if (!pr->performance) {
		seq_puts(seq, "<not supported>\n");
		goto end;
	}

	seq_printf(seq, "state count:             %d\n"
		   "active state:            P%d\n",
		   pr->performance->state_count, pr->performance->state);

	seq_puts(seq, "states:\n");
	for (i = 0; i < pr->performance->state_count; i++)
		seq_printf(seq,
			   "   %cP%d:                  %d MHz, %d mW, %d uS\n",
			   (i == pr->performance->state ? '*' : ' '), i,
			   (u32) pr->performance->states[i].core_frequency,
			   (u32) pr->performance->states[i].power,
			   (u32) pr->performance->states[i].transition_latency);

      end:
	return_VALUE(0);
}

static int acpi_processor_perf_open_fs(struct inode *inode, struct file *file)
{
	return single_open(file, acpi_processor_perf_seq_show,
			   PDE(inode)->data);
}

static ssize_t
acpi_processor_write_performance(struct file *file,
				 const char __user * buffer,
				 size_t count, loff_t * data)
{
	int result = 0;
	struct seq_file *m = (struct seq_file *)file->private_data;
	struct acpi_processor *pr = (struct acpi_processor *)m->private;
	struct acpi_processor_performance *perf;
	char state_string[12] = { '\0' };
	unsigned int new_state = 0;
	struct cpufreq_policy policy;

	ACPI_FUNCTION_TRACE("acpi_processor_write_performance");

	if (!pr || (count > sizeof(state_string) - 1))
		return_VALUE(-EINVAL);

	perf = pr->performance;
	if (!perf)
		return_VALUE(-EINVAL);

	if (copy_from_user(state_string, buffer, count))
		return_VALUE(-EFAULT);

	state_string[count] = '\0';
	new_state = simple_strtoul(state_string, NULL, 0);

	if (new_state >= perf->state_count)
		return_VALUE(-EINVAL);

	cpufreq_get_policy(&policy, pr->id);

	policy.cpu = pr->id;
	policy.min = perf->states[new_state].core_frequency * 1000;
	policy.max = perf->states[new_state].core_frequency * 1000;

	result = cpufreq_set_policy(&policy);
	if (result)
		return_VALUE(result);

	return_VALUE(count);
}

static void acpi_cpufreq_add_file(struct acpi_processor *pr)
{
	struct proc_dir_entry *entry = NULL;
	struct acpi_device *device = NULL;

	ACPI_FUNCTION_TRACE("acpi_cpufreq_addfile");

	if (acpi_bus_get_device(pr->handle, &device))
		return_VOID;

	/* add file 'performance' [R/W] */
	entry = create_proc_entry(ACPI_PROCESSOR_FILE_PERFORMANCE,
				  S_IFREG | S_IRUGO | S_IWUSR,
				  acpi_device_dir(device));
	if (!entry)
		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
				  "Unable to create '%s' fs entry\n",
				  ACPI_PROCESSOR_FILE_PERFORMANCE));
	else {
		acpi_processor_perf_fops.write = acpi_processor_write_performance;
		entry->proc_fops = &acpi_processor_perf_fops;
		entry->data = acpi_driver_data(device);
		entry->owner = THIS_MODULE;
	}
	return_VOID;
}

static void acpi_cpufreq_remove_file(struct acpi_processor *pr)
{
	struct acpi_device *device = NULL;

	ACPI_FUNCTION_TRACE("acpi_cpufreq_addfile");

	if (acpi_bus_get_device(pr->handle, &device))
		return_VOID;

	/* remove file 'performance' */
	remove_proc_entry(ACPI_PROCESSOR_FILE_PERFORMANCE,
			  acpi_device_dir(device));

	return_VOID;
}

#else
static void acpi_cpufreq_add_file(struct acpi_processor *pr)
{
	return;
}
static void acpi_cpufreq_remove_file(struct acpi_processor *pr)
{
	return;
}
#endif				/* CONFIG_X86_ACPI_CPUFREQ_PROC_INTF */

int
acpi_processor_register_performance(struct acpi_processor_performance
				    *performance, unsigned int cpu)
{
	struct acpi_processor *pr;

	ACPI_FUNCTION_TRACE("acpi_processor_register_performance");

	if (!(acpi_processor_ppc_status & PPC_REGISTERED))
		return_VALUE(-EINVAL);

	down(&performance_sem);

	pr = processors[cpu];
	if (!pr) {
		up(&performance_sem);
		return_VALUE(-ENODEV);
	}

	if (pr->performance) {
		up(&performance_sem);
		return_VALUE(-EBUSY);
	}

	WARN_ON(!performance);

	pr->performance = performance;

	if (acpi_processor_get_performance_info(pr)) {
		pr->performance = NULL;
		up(&performance_sem);
		return_VALUE(-EIO);
	}

	acpi_cpufreq_add_file(pr);

	up(&performance_sem);
	return_VALUE(0);
}

EXPORT_SYMBOL(acpi_processor_register_performance);

void
acpi_processor_unregister_performance(struct acpi_processor_performance
				      *performance, unsigned int cpu)
{
	struct acpi_processor *pr;

	ACPI_FUNCTION_TRACE("acpi_processor_unregister_performance");

	down(&performance_sem);

	pr = processors[cpu];
	if (!pr) {
		up(&performance_sem);
		return_VOID;
	}

	if (pr->performance)
		kfree(pr->performance->states);
	pr->performance = NULL;

	acpi_cpufreq_remove_file(pr);

	up(&performance_sem);

	return_VOID;
}

EXPORT_SYMBOL(acpi_processor_unregister_performance);