1/*
2 *  (C) 2004-2009  Dominik Brodowski <linux@dominikbrodowski.de>
3 *
4 *  Licensed under the terms of the GNU GPL License version 2.
5 */
6
7
8#include <unistd.h>
9#include <stdio.h>
10#include <errno.h>
11#include <stdlib.h>
12#include <limits.h>
13#include <string.h>
14#include <ctype.h>
15
16#include <getopt.h>
17
18#include "cpufreq.h"
19#include "helpers/helpers.h"
20
21#define NORM_FREQ_LEN 32
22
23static struct option set_opts[] = {
24	{ .name = "min",	.has_arg = required_argument,	.flag = NULL,	.val = 'd'},
25	{ .name = "max",	.has_arg = required_argument,	.flag = NULL,	.val = 'u'},
26	{ .name = "governor",	.has_arg = required_argument,	.flag = NULL,	.val = 'g'},
27	{ .name = "freq",	.has_arg = required_argument,	.flag = NULL,	.val = 'f'},
28	{ .name = "related",	.has_arg = no_argument,		.flag = NULL,	.val='r'},
29	{ },
30};
31
32static void print_error(void)
33{
34	printf(_("Error setting new values. Common errors:\n"
35			"- Do you have proper administration rights? (super-user?)\n"
36			"- Is the governor you requested available and modprobed?\n"
37			"- Trying to set an invalid policy?\n"
38			"- Trying to set a specific frequency, but userspace governor is not available,\n"
39			"   for example because of hardware which cannot be set to a specific frequency\n"
40			"   or because the userspace governor isn't loaded?\n"));
41};
42
43struct freq_units {
44	char		*str_unit;
45	int		power_of_ten;
46};
47
48const struct freq_units def_units[] = {
49	{"hz", -3},
50	{"khz", 0}, /* default */
51	{"mhz", 3},
52	{"ghz", 6},
53	{"thz", 9},
54	{NULL, 0}
55};
56
57static void print_unknown_arg(void)
58{
59	printf(_("invalid or unknown argument\n"));
60}
61
62static unsigned long string_to_frequency(const char *str)
63{
64	char normalized[NORM_FREQ_LEN];
65	const struct freq_units *unit;
66	const char *scan;
67	char *end;
68	unsigned long freq;
69	int power = 0, match_count = 0, i, cp, pad;
70
71	while (*str == '0')
72		str++;
73
74	for (scan = str; isdigit(*scan) || *scan == '.'; scan++) {
75		if (*scan == '.' && match_count == 0)
76			match_count = 1;
77		else if (*scan == '.' && match_count == 1)
78			return 0;
79	}
80
81	if (*scan) {
82		match_count = 0;
83		for (unit = def_units; unit->str_unit; unit++) {
84			for (i = 0;
85			     scan[i] && tolower(scan[i]) == unit->str_unit[i];
86			     ++i)
87				continue;
88			if (scan[i])
89				continue;
90			match_count++;
91			power = unit->power_of_ten;
92		}
93		if (match_count != 1)
94			return 0;
95	}
96
97	/* count the number of digits to be copied */
98	for (cp = 0; isdigit(str[cp]); cp++)
99		continue;
100
101	if (str[cp] == '.') {
102		while (power > -1 && isdigit(str[cp+1]))
103			cp++, power--;
104	}
105	if (power >= -1)	/* not enough => pad */
106		pad = power + 1;
107	else			/* to much => strip */
108		pad = 0, cp += power + 1;
109	/* check bounds */
110	if (cp <= 0 || cp + pad > NORM_FREQ_LEN - 1)
111		return 0;
112
113	/* copy digits */
114	for (i = 0; i < cp; i++, str++) {
115		if (*str == '.')
116			str++;
117		normalized[i] = *str;
118	}
119	/* and pad */
120	for (; i < cp + pad; i++)
121		normalized[i] = '0';
122
123	/* round up, down ? */
124	match_count = (normalized[i-1] >= '5');
125	/* and drop the decimal part */
126	normalized[i-1] = 0; /* cp > 0 && pad >= 0 ==> i > 0 */
127
128	/* final conversion (and applying rounding) */
129	errno = 0;
130	freq = strtoul(normalized, &end, 10);
131	if (errno)
132		return 0;
133	else {
134		if (match_count && freq != ULONG_MAX)
135			freq++;
136		return freq;
137	}
138}
139
140static int do_new_policy(unsigned int cpu, struct cpufreq_policy *new_pol)
141{
142	struct cpufreq_policy *cur_pol = cpufreq_get_policy(cpu);
143	int ret;
144
145	if (!cur_pol) {
146		printf(_("wrong, unknown or unhandled CPU?\n"));
147		return -EINVAL;
148	}
149
150	if (!new_pol->min)
151		new_pol->min = cur_pol->min;
152
153	if (!new_pol->max)
154		new_pol->max = cur_pol->max;
155
156	if (!new_pol->governor)
157		new_pol->governor = cur_pol->governor;
158
159	ret = cpufreq_set_policy(cpu, new_pol);
160
161	cpufreq_put_policy(cur_pol);
162
163	return ret;
164}
165
166
167static int do_one_cpu(unsigned int cpu, struct cpufreq_policy *new_pol,
168		unsigned long freq, unsigned int pc)
169{
170	switch (pc) {
171	case 0:
172		return cpufreq_set_frequency(cpu, freq);
173
174	case 1:
175		/* if only one value of a policy is to be changed, we can
176		 * use a "fast path".
177		 */
178		if (new_pol->min)
179			return cpufreq_modify_policy_min(cpu, new_pol->min);
180		else if (new_pol->max)
181			return cpufreq_modify_policy_max(cpu, new_pol->max);
182		else if (new_pol->governor)
183			return cpufreq_modify_policy_governor(cpu,
184							new_pol->governor);
185
186	default:
187		/* slow path */
188		return do_new_policy(cpu, new_pol);
189	}
190}
191
192int cmd_freq_set(int argc, char **argv)
193{
194	extern char *optarg;
195	extern int optind, opterr, optopt;
196	int ret = 0, cont = 1;
197	int double_parm = 0, related = 0, policychange = 0;
198	unsigned long freq = 0;
199	char gov[20];
200	unsigned int cpu;
201
202	struct cpufreq_policy new_pol = {
203		.min = 0,
204		.max = 0,
205		.governor = NULL,
206	};
207
208	/* parameter parsing */
209	do {
210		ret = getopt_long(argc, argv, "d:u:g:f:r", set_opts, NULL);
211		switch (ret) {
212		case '?':
213			print_unknown_arg();
214			return -EINVAL;
215		case -1:
216			cont = 0;
217			break;
218		case 'r':
219			if (related)
220				double_parm++;
221			related++;
222			break;
223		case 'd':
224			if (new_pol.min)
225				double_parm++;
226			policychange++;
227			new_pol.min = string_to_frequency(optarg);
228			if (new_pol.min == 0) {
229				print_unknown_arg();
230				return -EINVAL;
231			}
232			break;
233		case 'u':
234			if (new_pol.max)
235				double_parm++;
236			policychange++;
237			new_pol.max = string_to_frequency(optarg);
238			if (new_pol.max == 0) {
239				print_unknown_arg();
240				return -EINVAL;
241			}
242			break;
243		case 'f':
244			if (freq)
245				double_parm++;
246			freq = string_to_frequency(optarg);
247			if (freq == 0) {
248				print_unknown_arg();
249				return -EINVAL;
250			}
251			break;
252		case 'g':
253			if (new_pol.governor)
254				double_parm++;
255			policychange++;
256			if ((strlen(optarg) < 3) || (strlen(optarg) > 18)) {
257				print_unknown_arg();
258				return -EINVAL;
259			}
260			if ((sscanf(optarg, "%19s", gov)) != 1) {
261				print_unknown_arg();
262				return -EINVAL;
263			}
264			new_pol.governor = gov;
265			break;
266		}
267	} while (cont);
268
269	/* parameter checking */
270	if (double_parm) {
271		printf("the same parameter was passed more than once\n");
272		return -EINVAL;
273	}
274
275	if (freq && policychange) {
276		printf(_("the -f/--freq parameter cannot be combined with -d/--min, -u/--max or\n"
277				"-g/--governor parameters\n"));
278		return -EINVAL;
279	}
280
281	if (!freq && !policychange) {
282		printf(_("At least one parameter out of -f/--freq, -d/--min, -u/--max, and\n"
283				"-g/--governor must be passed\n"));
284		return -EINVAL;
285	}
286
287	/* Default is: set all CPUs */
288	if (bitmask_isallclear(cpus_chosen))
289		bitmask_setall(cpus_chosen);
290
291	/* Also set frequency settings for related CPUs if -r is passed */
292	if (related) {
293		for (cpu = bitmask_first(cpus_chosen);
294		     cpu <= bitmask_last(cpus_chosen); cpu++) {
295			struct cpufreq_affected_cpus *cpus;
296
297			if (!bitmask_isbitset(cpus_chosen, cpu) ||
298			    cpufreq_cpu_exists(cpu))
299				continue;
300
301			cpus = cpufreq_get_related_cpus(cpu);
302			if (!cpus)
303				break;
304			while (cpus->next) {
305				bitmask_setbit(cpus_chosen, cpus->cpu);
306				cpus = cpus->next;
307			}
308			cpufreq_put_related_cpus(cpus);
309		}
310	}
311
312
313	/* loop over CPUs */
314	for (cpu = bitmask_first(cpus_chosen);
315	     cpu <= bitmask_last(cpus_chosen); cpu++) {
316
317		if (!bitmask_isbitset(cpus_chosen, cpu) ||
318		    cpufreq_cpu_exists(cpu))
319			continue;
320
321		printf(_("Setting cpu: %d\n"), cpu);
322		ret = do_one_cpu(cpu, &new_pol, freq, policychange);
323		if (ret) {
324			print_error();
325			return ret;
326		}
327	}
328
329	return 0;
330}
331