aboutsummaryrefslogtreecommitdiffstats
path: root/tools/power/cpupower/utils/cpufreq-info.c
blob: 5a1d25f056b3b60c0f547cc43314d03272fcfac7 (plain) (blame)
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
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
/*
 *  (C) 2004-2009  Dominik Brodowski <linux@dominikbrodowski.de>
 *
 *  Licensed under the terms of the GNU GPL License version 2.
 */


#include <unistd.h>
#include <stdio.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>

#include <getopt.h>

#include "cpufreq.h"
#include "helpers/helpers.h"
#include "helpers/bitmask.h"

#define LINE_LEN 10

static unsigned int count_cpus(void)
{
	FILE *fp;
	char value[LINE_LEN];
	unsigned int ret = 0;
	unsigned int cpunr = 0;

	fp = fopen("/proc/stat", "r");
	if (!fp) {
		printf(_("Couldn't count the number of CPUs (%s: %s), assuming 1\n"), "/proc/stat", strerror(errno));
		return 1;
	}

	while (!feof(fp)) {
		if (!fgets(value, LINE_LEN, fp))
			continue;
		value[LINE_LEN - 1] = '\0';
		if (strlen(value) < (LINE_LEN - 2))
			continue;
		if (strstr(value, "cpu "))
			continue;
		if (sscanf(value, "cpu%d ", &cpunr) != 1)
			continue;
		if (cpunr > ret)
			ret = cpunr;
	}
	fclose(fp);

	/* cpu count starts from 0, on error return 1 (UP) */
	return ret + 1;
}


static void proc_cpufreq_output(void)
{
	unsigned int cpu, nr_cpus;
	struct cpufreq_policy *policy;
	unsigned int min_pctg = 0;
	unsigned int max_pctg = 0;
	unsigned long min, max;

	printf(_("          minimum CPU frequency  -  maximum CPU frequency  -  governor\n"));

	nr_cpus = count_cpus();
	for (cpu = 0; cpu < nr_cpus; cpu++) {
		policy = cpufreq_get_policy(cpu);
		if (!policy)
			continue;

		if (cpufreq_get_hardware_limits(cpu, &min, &max)) {
			max = 0;
		} else {
			min_pctg = (policy->min * 100) / max;
			max_pctg = (policy->max * 100) / max;
		}
		printf("CPU%3d    %9lu kHz (%3d %%)  -  %9lu kHz (%3d %%)  -  %s\n",
			cpu , policy->min, max ? min_pctg : 0, policy->max,
			max ? max_pctg : 0, policy->governor);

		cpufreq_put_policy(policy);
	}
}

static void print_speed(unsigned long speed)
{
	unsigned long tmp;

	if (speed > 1000000) {
		tmp = speed % 10000;
		if (tmp >= 5000)
			speed += 10000;
		printf("%u.%02u GHz", ((unsigned int) speed/1000000),
			((unsigned int) (speed%1000000)/10000));
	} else if (speed > 100000) {
		tmp = speed % 1000;
		if (tmp >= 500)
			speed += 1000;
		printf("%u MHz", ((unsigned int) speed / 1000));
	} else if (speed > 1000) {
		tmp = speed % 100;
		if (tmp >= 50)
			speed += 100;
		printf("%u.%01u MHz", ((unsigned int) speed/1000),
			((unsigned int) (speed%1000)/100));
	} else
		printf("%lu kHz", speed);

	return;
}

static void print_duration(unsigned long duration)
{
	unsigned long tmp;

	if (duration > 1000000) {
		tmp = duration % 10000;
		if (tmp >= 5000)
			duration += 10000;
		printf("%u.%02u ms", ((unsigned int) duration/1000000),
			((unsigned int) (duration%1000000)/10000));
	} else if (duration > 100000) {
		tmp = duration % 1000;
		if (tmp >= 500)
			duration += 1000;
		printf("%u us", ((unsigned int) duration / 1000));
	} else if (duration > 1000) {
		tmp = duration % 100;
		if (tmp >= 50)
			duration += 100;
		printf("%u.%01u us", ((unsigned int) duration/1000),
			((unsigned int) (duration%1000)/100));
	} else
		printf("%lu ns", duration);

	return;
}

/* --boost / -b */

static int get_boost_mode(unsigned int cpu)
{
	int support, active, b_states = 0, ret, pstate_no, i;
	/* ToDo: Make this more global */
	unsigned long pstates[MAX_HW_PSTATES] = {0,};

	if (cpupower_cpu_info.vendor != X86_VENDOR_AMD &&
	    cpupower_cpu_info.vendor != X86_VENDOR_INTEL)
		return 0;

	ret = cpufreq_has_boost_support(cpu, &support, &active, &b_states);
	if (ret) {
		printf(_("Error while evaluating Boost Capabilities"
				" on CPU %d -- are you root?\n"), cpu);
		return ret;
	}
	/* P state changes via MSR are identified via cpuid 80000007
	   on Intel and AMD, but we assume boost capable machines can do that
	   if (cpuid_eax(0x80000000) >= 0x80000007
	   && (cpuid_edx(0x80000007) & (1 << 7)))
	*/

	printf(_("  boost state support:\n"));

	printf(_("    Supported: %s\n"), support ? _("yes") : _("no"));
	printf(_("    Active: %s\n"), active ? _("yes") : _("no"));

	if (cpupower_cpu_info.vendor == X86_VENDOR_AMD &&
	    cpupower_cpu_info.family >= 0x10) {
		ret = decode_pstates(cpu, cpupower_cpu_info.family, b_states,
				     pstates, &pstate_no);
		if (ret)
			return ret;

		printf(_("    Boost States: %d\n"), b_states);
		printf(_("    Total States: %d\n"), pstate_no);
		for (i = 0; i < pstate_no; i++) {
			if (i < b_states)
				printf(_("    Pstate-Pb%d: %luMHz (boost state)"
					 "\n"), i, pstates[i]);
			else
				printf(_("    Pstate-P%d:  %luMHz\n"),
				       i - b_states, pstates[i]);
		}
	} else if (cpupower_cpu_info.caps & CPUPOWER_CAP_HAS_TURBO_RATIO) {
		double bclk;
		unsigned long long intel_turbo_ratio = 0;
		unsigned int ratio;

		/* Any way to autodetect this ? */
		if (cpupower_cpu_info.caps & CPUPOWER_CAP_IS_SNB)
			bclk = 100.00;
		else
			bclk = 133.33;
		intel_turbo_ratio = msr_intel_get_turbo_ratio(cpu);
		dprint ("    Ratio: 0x%llx - bclk: %f\n",
			intel_turbo_ratio, bclk);

		ratio = (intel_turbo_ratio >> 24) & 0xFF;
		if (ratio)
			printf(_("    %.0f MHz max turbo 4 active cores\n"),
			       ratio * bclk);

		ratio = (intel_turbo_ratio >> 16) & 0xFF;
		if (ratio)
			printf(_("    %.0f MHz max turbo 3 active cores\n"),
			       ratio * bclk);

		ratio = (intel_turbo_ratio >> 8) & 0xFF;
		if (ratio)
			printf(_("    %.0f MHz max turbo 2 active cores\n"),
			       ratio * bclk);

		ratio = (intel_turbo_ratio >> 0) & 0xFF;
		if (ratio)
			printf(_("    %.0f MHz max turbo 1 active cores\n"),
			       ratio * bclk);
	}
	return 0;
}

static void debug_output_one(unsigned int cpu)
{
	char *driver;
	struct cpufreq_affected_cpus *cpus;
	struct cpufreq_available_frequencies *freqs;
	unsigned long min, max, freq_kernel, freq_hardware;
	unsigned long total_trans, latency;
	unsigned long long total_time;
	struct cpufreq_policy *policy;
	struct cpufreq_available_governors *governors;
	struct cpufreq_stats *stats;

	if (cpufreq_cpu_exists(cpu))
		return;

	freq_kernel = cpufreq_get_freq_kernel(cpu);
	freq_hardware = cpufreq_get_freq_hardware(cpu);

	driver = cpufreq_get_driver(cpu);
	if (!driver) {
		printf(_("  no or unknown cpufreq driver is active on this CPU\n"));
	} else {
		printf(_("  driver: %s\n"), driver);
		cpufreq_put_driver(driver);
	}

	cpus = cpufreq_get_related_cpus(cpu);
	if (cpus) {
		printf(_("  CPUs which run at the same hardware frequency: "));
		while (cpus->next) {
			printf("%d ", cpus->cpu);
			cpus = cpus->next;
		}
		printf("%d\n", cpus->cpu);
		cpufreq_put_related_cpus(cpus);
	}

	cpus = cpufreq_get_affected_cpus(cpu);
	if (cpus) {
		printf(_("  CPUs which need to have their frequency coordinated by software: "));
		while (cpus->next) {
			printf("%d ", cpus->cpu);
			cpus = cpus->next;
		}
		printf("%d\n", cpus->cpu);
		cpufreq_put_affected_cpus(cpus);
	}

	latency = cpufreq_get_transition_latency(cpu);
	if (latency) {
		printf(_("  maximum transition latency: "));
		print_duration(latency);
		printf(".\n");
	}

	if (!(cpufreq_get_hardware_limits(cpu, &min, &max))) {
		printf(_("  hardware limits: "));
		print_speed(min);
		printf(" - ");
		print_speed(max);
		printf("\n");
	}

	freqs = cpufreq_get_available_frequencies(cpu);
	if (freqs) {
		printf(_("  available frequency steps: "));
		while (freqs->next) {
			print_speed(freqs->frequency);
			printf(", ");
			freqs = freqs->next;
		}
		print_speed(freqs->frequency);
		printf("\n");
		cpufreq_put_available_frequencies(freqs);
	}

	governors = cpufreq_get_available_governors(cpu);
	if (governors) {
		printf(_("  available cpufreq governors: "));
		while (governors->next) {
			printf("%s, ", governors->governor);
			governors = governors->next;
		}
		printf("%s\n", governors->governor);
		cpufreq_put_available_governors(governors);
	}

	policy = cpufreq_get_policy(cpu);
	if (policy) {
		printf(_("  current policy: frequency should be within "));
		print_speed(policy->min);
		printf(_(" and "));
		print_speed(policy->max);

		printf(".\n                  ");
		printf(_("The governor \"%s\" may"
		       " decide which speed to use\n                  within this range.\n"),
		       policy->governor);
		cpufreq_put_policy(policy);
	}

	if (freq_kernel || freq_hardware) {
		printf(_("  current CPU frequency is "));
		if (freq_hardware) {
			print_speed(freq_hardware);
			printf(_(" (asserted by call to hardware)"));
		} else
			print_speed(freq_kernel);
		printf(".\n");
	}
	stats = cpufreq_get_stats(cpu, &total_time);
	if (stats) {
		printf(_("  cpufreq stats: "));
		while (stats) {
			print_speed(stats->frequency);
			printf(":%.2f%%", (100.0 * stats->time_in_state) / total_time);
			stats = stats->next;
			if (stats)
				printf(", ");
		}
		cpufreq_put_stats(stats);
		total_trans = cpufreq_get_transitions(cpu);
		if (total_trans)
			printf("  (%lu)\n", total_trans);
		else
			printf("\n");
	}
	get_boost_mode(cpu);

}

/* --freq / -f */

static int get_freq_kernel(unsigned int cpu, unsigned int human)
{
	unsigned long freq = cpufreq_get_freq_kernel(cpu);
	if (!freq)
		return -EINVAL;
	if (human) {
		print_speed(freq);
		printf("\n");
	} else
		printf("%lu\n", freq);
	return 0;
}


/* --hwfreq / -w */

static int get_freq_hardware(unsigned int cpu, unsigned int human)
{
	unsigned long freq = cpufreq_get_freq_hardware(cpu);
	if (!freq)
		return -EINVAL;
	if (human) {
		print_speed(freq);
		printf("\n");
	} else
		printf("%lu\n", freq);
	return 0;
}

/* --hwlimits / -l */

static int get_hardware_limits(unsigned int cpu)
{
	unsigned long min, max;
	if (cpufreq_get_hardware_limits(cpu, &min, &max))
		return -EINVAL;
	printf("%lu %lu\n", min, max);
	return 0;
}

/* --driver / -d */

static int get_driver(unsigned int cpu)
{
	char *driver = cpufreq_get_driver(cpu);
	if (!driver)
		return -EINVAL;
	printf("%s\n", driver);
	cpufreq_put_driver(driver);
	return 0;
}

/* --policy / -p */

static int get_policy(unsigned int cpu)
{
	struct cpufreq_policy *policy = cpufreq_get_policy(cpu);
	if (!policy)
		return -EINVAL;
	printf("%lu %lu %s\n", policy->min, policy->max, policy->governor);
	cpufreq_put_policy(policy);
	return 0;
}

/* --governors / -g */

static int get_available_governors(unsigned int cpu)
{
	struct cpufreq_available_governors *governors =
		cpufreq_get_available_governors(cpu);
	if (!governors)
		return -EINVAL;

	while (governors->next) {
		printf("%s ", governors->governor);
		governors = governors->next;
	}
	printf("%s\n", governors->governor);
	cpufreq_put_available_governors(governors);
	return 0;
}


/* --affected-cpus  / -a */

static int get_affected_cpus(unsigned int cpu)
{
	struct cpufreq_affected_cpus *cpus = cpufreq_get_affected_cpus(cpu);
	if (!cpus)
		return -EINVAL;

	while (cpus->next) {
		printf("%d ", cpus->cpu);
		cpus = cpus->next;
	}
	printf("%d\n", cpus->cpu);
	cpufreq_put_affected_cpus(cpus);
	return 0;
}

/* --related-cpus  / -r */

static int get_related_cpus(unsigned int cpu)
{
	struct cpufreq_affected_cpus *cpus = cpufreq_get_related_cpus(cpu);
	if (!cpus)
		return -EINVAL;

	while (cpus->next) {
		printf("%d ", cpus->cpu);
		cpus = cpus->next;
	}
	printf("%d\n", cpus->cpu);
	cpufreq_put_related_cpus(cpus);
	return 0;
}

/* --stats / -s */

static int get_freq_stats(unsigned int cpu, unsigned int human)
{
	unsigned long total_trans = cpufreq_get_transitions(cpu);
	unsigned long long total_time;
	struct cpufreq_stats *stats = cpufreq_get_stats(cpu, &total_time);
	while (stats) {
		if (human) {
			print_speed(stats->frequency);
			printf(":%.2f%%",
				(100.0 * stats->time_in_state) / total_time);
		} else
			printf("%lu:%llu",
				stats->frequency, stats->time_in_state);
		stats = stats->next;
		if (stats)
			printf(", ");
	}
	cpufreq_put_stats(stats);
	if (total_trans)
		printf("  (%lu)\n", total_trans);
	return 0;
}

/* --latency / -y */

static int get_latency(unsigned int cpu, unsigned int human)
{
	unsigned long latency = cpufreq_get_transition_latency(cpu);
	if (!latency)
		return -EINVAL;

	if (human) {
		print_duration(latency);
		printf("\n");
	} else
		printf("%lu\n", latency);
	return 0;
}

void freq_info_help(void)
{
	printf(_("Usage: cpupower freqinfo [options]\n"));
	printf(_("Options:\n"));
	printf(_("  -e, --debug          Prints out debug information [default]\n"));
	printf(_("  -f, --freq           Get frequency the CPU currently runs at, according\n"
	       "                       to the cpufreq core *\n"));
	printf(_("  -w, --hwfreq         Get frequency the CPU currently runs at, by reading\n"
	       "                       it from hardware (only available to root) *\n"));
	printf(_("  -l, --hwlimits       Determine the minimum and maximum CPU frequency allowed *\n"));
	printf(_("  -d, --driver         Determines the used cpufreq kernel driver *\n"));
	printf(_("  -p, --policy         Gets the currently used cpufreq policy *\n"));
	printf(_("  -g, --governors      Determines available cpufreq governors *\n"));
	printf(_("  -r, --related-cpus   Determines which CPUs run at the same hardware frequency *\n"));
	printf(_("  -a, --affected-cpus  Determines which CPUs need to have their frequency\n"
			"                       coordinated by software *\n"));
	printf(_("  -s, --stats          Shows cpufreq statistics if available\n"));
	printf(_("  -y, --latency        Determines the maximum latency on CPU frequency changes *\n"));
	printf(_("  -b, --boost          Checks for turbo or boost modes  *\n"));
	printf(_("  -o, --proc           Prints out information like provided by the /proc/cpufreq\n"
	       "                       interface in 2.4. and early 2.6. kernels\n"));
	printf(_("  -m, --human          human-readable output for the -f, -w, -s and -y parameters\n"));
	printf(_("  -h, --help           Prints out this screen\n"));

	printf("\n");
	printf(_("If no argument is given, full output about\n"
	       "cpufreq is printed which is useful e.g. for reporting bugs.\n\n"));
	printf(_("By default info of CPU 0 is shown which can be overridden\n"
		 "with the cpupower --cpu main command option.\n"));
}

static struct option info_opts[] = {
	{ .name = "debug",	.has_arg = no_argument,		.flag = NULL,	.val = 'e'},
	{ .name = "boost",	.has_arg = no_argument,		.flag = NULL,	.val = 'b'},
	{ .name = "freq",	.has_arg = no_argument,		.flag = NULL,	.val = 'f'},
	{ .name = "hwfreq",	.has_arg = no_argument,		.flag = NULL,	.val = 'w'},
	{ .name = "hwlimits",	.has_arg = no_argument,		.flag = NULL,	.val = 'l'},
	{ .name = "driver",	.has_arg = no_argument,		.flag = NULL,	.val = 'd'},
	{ .name = "policy",	.has_arg = no_argument,		.flag = NULL,	.val = 'p'},
	{ .name = "governors",	.has_arg = no_argument,		.flag = NULL,	.val = 'g'},
	{ .name = "related-cpus", .has_arg = no_argument,	.flag = NULL,	.val = 'r'},
	{ .name = "affected-cpus",.has_arg = no_argument,	.flag = NULL,	.val = 'a'},
	{ .name = "stats",	.has_arg = no_argument,		.flag = NULL,	.val = 's'},
	{ .name = "latency",	.has_arg = no_argument,		.flag = NULL,	.val = 'y'},
	{ .name = "proc",	.has_arg = no_argument,		.flag = NULL,	.val = 'o'},
	{ .name = "human",	.has_arg = no_argument,		.flag = NULL,	.val = 'm'},
	{ .name = "help",	.has_arg = no_argument,		.flag = NULL,	.val = 'h'},
	{ },
};

int cmd_freq_info(int argc, char **argv)
{
	extern char *optarg;
	extern int optind, opterr, optopt;
	int ret = 0, cont = 1;
	unsigned int cpu = 0;
	unsigned int human = 0;
	int output_param = 0;

	do {
		ret = getopt_long(argc, argv, "hoefwldpgrasmyb", info_opts, NULL);
		switch (ret) {
		case '?':
			output_param = '?';
			cont = 0;
			break;
		case 'h':
			output_param = 'h';
			cont = 0;
			break;
		case -1:
			cont = 0;
			break;
		case 'b':
		case 'o':
		case 'a':
		case 'r':
		case 'g':
		case 'p':
		case 'd':
		case 'l':
		case 'w':
		case 'f':
		case 'e':
		case 's':
		case 'y':
			if (output_param) {
				output_param = -1;
				cont = 0;
				break;
			}
			output_param = ret;
			break;
		case 'm':
			if (human) {
				output_param = -1;
				cont = 0;
				break;
			}
			human = 1;
			break;
		default:
			fprintf(stderr, "invalid or unknown argument\n");
			return EXIT_FAILURE;
		}
	} while (cont);

	switch (output_param) {
	case 'o':
		if (!bitmask_isallclear(cpus_chosen)) {
			printf(_("The argument passed to this tool can't be "
				 "combined with passing a --cpu argument\n"));
			return -EINVAL;
		}
		break;
	case 0:
		output_param = 'e';
	}

	ret = 0;

	/* Default is: show output of CPU 0 only */
	if (bitmask_isallclear(cpus_chosen))
		bitmask_setbit(cpus_chosen, 0);

	switch (output_param) {
	case -1:
		printf(_("You can't specify more than one --cpu parameter and/or\n"
		       "more than one output-specific argument\n"));
		return -EINVAL;
	case '?':
		printf(_("invalid or unknown argument\n"));
		freq_info_help();
		return -EINVAL;
	case 'h':
		freq_info_help();
		return EXIT_SUCCESS;
	case 'o':
		proc_cpufreq_output();
		return EXIT_SUCCESS;
	}

	for (cpu = bitmask_first(cpus_chosen);
	     cpu <= bitmask_last(cpus_chosen); cpu++) {

		if (!bitmask_isbitset(cpus_chosen, cpu))
			continue;
		if (cpufreq_cpu_exists(cpu)) {
			printf(_("couldn't analyze CPU %d as it doesn't seem to be present\n"), cpu);
			continue;
		}
		printf(_("analyzing CPU %d:\n"), cpu);

		switch (output_param) {
		case 'b':
			get_boost_mode(cpu);
			break;
		case 'e':
			debug_output_one(cpu);
			break;
		case 'a':
			ret = get_affected_cpus(cpu);
			break;
		case 'r':
			ret = get_related_cpus(cpu);
			break;
		case 'g':
			ret = get_available_governors(cpu);
			break;
		case 'p':
			ret = get_policy(cpu);
			break;
		case 'd':
			ret = get_driver(cpu);
			break;
		case 'l':
			ret = get_hardware_limits(cpu);
			break;
		case 'w':
			ret = get_freq_hardware(cpu, human);
			break;
		case 'f':
			ret = get_freq_kernel(cpu, human);
			break;
		case 's':
			ret = get_freq_stats(cpu, human);
			break;
		case 'y':
			ret = get_latency(cpu, human);
			break;
		}
		if (ret)
			return ret;
	}
	return ret;
}