aboutsummaryrefslogtreecommitdiffstats
path: root/tools/power/cpupower/utils/cpufreq-set.c
blob: a416de80c55ea120f83b183b1b0db2aa824e2c22 (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
/*
 *  (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 <limits.h>
#include <string.h>
#include <ctype.h>

#include <getopt.h>

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

#define NORM_FREQ_LEN 32

static struct option set_opts[] = {
	{ .name = "min",	.has_arg = required_argument,	.flag = NULL,	.val = 'd'},
	{ .name = "max",	.has_arg = required_argument,	.flag = NULL,	.val = 'u'},
	{ .name = "governor",	.has_arg = required_argument,	.flag = NULL,	.val = 'g'},
	{ .name = "freq",	.has_arg = required_argument,	.flag = NULL,	.val = 'f'},
	{ .name = "related",	.has_arg = no_argument,		.flag = NULL,	.val='r'},
	{ },
};

static void print_error(void)
{
	printf(_("Error setting new values. Common errors:\n"
			"- Do you have proper administration rights? (super-user?)\n"
			"- Is the governor you requested available and modprobed?\n"
			"- Trying to set an invalid policy?\n"
			"- Trying to set a specific frequency, but userspace governor is not available,\n"
			"   for example because of hardware which cannot be set to a specific frequency\n"
			"   or because the userspace governor isn't loaded?\n"));
};

struct freq_units {
	char		*str_unit;
	int		power_of_ten;
};

const struct freq_units def_units[] = {
	{"hz", -3},
	{"khz", 0}, /* default */
	{"mhz", 3},
	{"ghz", 6},
	{"thz", 9},
	{NULL, 0}
};

static void print_unknown_arg(void)
{
	printf(_("invalid or unknown argument\n"));
}

static unsigned long string_to_frequency(const char *str)
{
	char normalized[NORM_FREQ_LEN];
	const struct freq_units *unit;
	const char *scan;
	char *end;
	unsigned long freq;
	int power = 0, match_count = 0, i, cp, pad;

	while (*str == '0')
		str++;

	for (scan = str; isdigit(*scan) || *scan == '.'; scan++) {
		if (*scan == '.' && match_count == 0)
			match_count = 1;
		else if (*scan == '.' && match_count == 1)
			return 0;
	}

	if (*scan) {
		match_count = 0;
		for (unit = def_units; unit->str_unit; unit++) {
			for (i = 0;
			     scan[i] && tolower(scan[i]) == unit->str_unit[i];
			     ++i)
				continue;
			if (scan[i])
				continue;
			match_count++;
			power = unit->power_of_ten;
		}
		if (match_count != 1)
			return 0;
	}

	/* count the number of digits to be copied */
	for (cp = 0; isdigit(str[cp]); cp++)
		continue;

	if (str[cp] == '.') {
		while (power > -1 && isdigit(str[cp+1]))
			cp++, power--;
	}
	if (power >= -1)	/* not enough => pad */
		pad = power + 1;
	else			/* to much => strip */
		pad = 0, cp += power + 1;
	/* check bounds */
	if (cp <= 0 || cp + pad > NORM_FREQ_LEN - 1)
		return 0;

	/* copy digits */
	for (i = 0; i < cp; i++, str++) {
		if (*str == '.')
			str++;
		normalized[i] = *str;
	}
	/* and pad */
	for (; i < cp + pad; i++)
		normalized[i] = '0';

	/* round up, down ? */
	match_count = (normalized[i-1] >= '5');
	/* and drop the decimal part */
	normalized[i-1] = 0; /* cp > 0 && pad >= 0 ==> i > 0 */

	/* final conversion (and applying rounding) */
	errno = 0;
	freq = strtoul(normalized, &end, 10);
	if (errno)
		return 0;
	else {
		if (match_count && freq != ULONG_MAX)
			freq++;
		return freq;
	}
}

static int do_new_policy(unsigned int cpu, struct cpufreq_policy *new_pol)
{
	struct cpufreq_policy *cur_pol = cpufreq_get_policy(cpu);
	int ret;

	if (!cur_pol) {
		printf(_("wrong, unknown or unhandled CPU?\n"));
		return -EINVAL;
	}

	if (!new_pol->min)
		new_pol->min = cur_pol->min;

	if (!new_pol->max)
		new_pol->max = cur_pol->max;

	if (!new_pol->governor)
		new_pol->governor = cur_pol->governor;

	ret = cpufreq_set_policy(cpu, new_pol);

	cpufreq_put_policy(cur_pol);

	return ret;
}


static int do_one_cpu(unsigned int cpu, struct cpufreq_policy *new_pol,
		unsigned long freq, unsigned int pc)
{
	switch (pc) {
	case 0:
		return cpufreq_set_frequency(cpu, freq);

	case 1:
		/* if only one value of a policy is to be changed, we can
		 * use a "fast path".
		 */
		if (new_pol->min)
			return cpufreq_modify_policy_min(cpu, new_pol->min);
		else if (new_pol->max)
			return cpufreq_modify_policy_max(cpu, new_pol->max);
		else if (new_pol->governor)
			return cpufreq_modify_policy_governor(cpu,
							new_pol->governor);

	default:
		/* slow path */
		return do_new_policy(cpu, new_pol);
	}
}

int cmd_freq_set(int argc, char **argv)
{
	extern char *optarg;
	extern int optind, opterr, optopt;
	int ret = 0, cont = 1;
	int double_parm = 0, related = 0, policychange = 0;
	unsigned long freq = 0;
	char gov[20];
	unsigned int cpu;

	struct cpufreq_policy new_pol = {
		.min = 0,
		.max = 0,
		.governor = NULL,
	};

	/* parameter parsing */
	do {
		ret = getopt_long(argc, argv, "d:u:g:f:r", set_opts, NULL);
		switch (ret) {
		case '?':
			print_unknown_arg();
			return -EINVAL;
		case -1:
			cont = 0;
			break;
		case 'r':
			if (related)
				double_parm++;
			related++;
			break;
		case 'd':
			if (new_pol.min)
				double_parm++;
			policychange++;
			new_pol.min = string_to_frequency(optarg);
			if (new_pol.min == 0) {
				print_unknown_arg();
				return -EINVAL;
			}
			break;
		case 'u':
			if (new_pol.max)
				double_parm++;
			policychange++;
			new_pol.max = string_to_frequency(optarg);
			if (new_pol.max == 0) {
				print_unknown_arg();
				return -EINVAL;
			}
			break;
		case 'f':
			if (freq)
				double_parm++;
			freq = string_to_frequency(optarg);
			if (freq == 0) {
				print_unknown_arg();
				return -EINVAL;
			}
			break;
		case 'g':
			if (new_pol.governor)
				double_parm++;
			policychange++;
			if ((strlen(optarg) < 3) || (strlen(optarg) > 18)) {
				print_unknown_arg();
				return -EINVAL;
			}
			if ((sscanf(optarg, "%19s", gov)) != 1) {
				print_unknown_arg();
				return -EINVAL;
			}
			new_pol.governor = gov;
			break;
		}
	} while (cont);

	/* parameter checking */
	if (double_parm) {
		printf("the same parameter was passed more than once\n");
		return -EINVAL;
	}

	if (freq && policychange) {
		printf(_("the -f/--freq parameter cannot be combined with -d/--min, -u/--max or\n"
				"-g/--governor parameters\n"));
		return -EINVAL;
	}

	if (!freq && !policychange) {
		printf(_("At least one parameter out of -f/--freq, -d/--min, -u/--max, and\n"
				"-g/--governor must be passed\n"));
		return -EINVAL;
	}

	/* Default is: set all CPUs */
	if (bitmask_isallclear(cpus_chosen))
		bitmask_setall(cpus_chosen);

	/* Also set frequency settings for related CPUs if -r is passed */
	if (related) {
		for (cpu = bitmask_first(cpus_chosen);
		     cpu <= bitmask_last(cpus_chosen); cpu++) {
			struct cpufreq_affected_cpus *cpus;

			if (!bitmask_isbitset(cpus_chosen, cpu) ||
			    cpufreq_cpu_exists(cpu))
				continue;

			cpus = cpufreq_get_related_cpus(cpu);
			if (!cpus)
				break;
			while (cpus->next) {
				bitmask_setbit(cpus_chosen, cpus->cpu);
				cpus = cpus->next;
			}
			cpufreq_put_related_cpus(cpus);
		}
	}


	/* loop over CPUs */
	for (cpu = bitmask_first(cpus_chosen);
	     cpu <= bitmask_last(cpus_chosen); cpu++) {

		if (!bitmask_isbitset(cpus_chosen, cpu) ||
		    cpufreq_cpu_exists(cpu))
			continue;

		printf(_("Setting cpu: %d\n"), cpu);
		ret = do_one_cpu(cpu, &new_pol, freq, policychange);
		if (ret)
			break;
	}

	if (ret)
		print_error();

	return ret;
}