kernel/tools/power/cpupower/utils/cpufreq-set.c

   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 #include "helpers/sysfs.h"
  21
  22 #define NORM_FREQ_LEN 32
  23
  24 static struct option set_opts[] = {
  25         {"min",         required_argument,      NULL, 'd'},
  26         {"max",         required_argument,      NULL, 'u'},
  27         {"governor",    required_argument,      NULL, 'g'},
  28         {"freq",        required_argument,      NULL, 'f'},
  29         {"related",     no_argument,            NULL, 'r'},
  30         { },
  31 };
  32
  33 static void print_error(void)
  34 {
  35         printf(_("Error setting new values. Common errors:\n"
  36                         "- Do you have proper administration rights? (super-user?)\n"
  37                         "- Is the governor you requested available and modprobed?\n"
  38                         "- Trying to set an invalid policy?\n"
  39                         "- Trying to set a specific frequency, but userspace governor is not available,\n"
  40                         "   for example because of hardware which cannot be set to a specific frequency\n"
  41                         "   or because the userspace governor isn't loaded?\n"));
  42 };
  43
  44 struct freq_units {
  45         char            *str_unit;
  46         int             power_of_ten;
  47 };
  48
  49 const struct freq_units def_units[] = {
  50         {"hz", -3},
  51         {"khz", 0}, /* default */
  52         {"mhz", 3},
  53         {"ghz", 6},
  54         {"thz", 9},
  55         {NULL, 0}
  56 };
  57
  58 static void print_unknown_arg(void)
  59 {
  60         printf(_("invalid or unknown argument\n"));
  61 }
  62
  63 static unsigned long string_to_frequency(const char *str)
  64 {
  65         char normalized[NORM_FREQ_LEN];
  66         const struct freq_units *unit;
  67         const char *scan;
  68         char *end;
  69         unsigned long freq;
  70         int power = 0, match_count = 0, i, cp, pad;
  71
  72         while (*str == '0')
  73                 str++;
  74
  75         for (scan = str; isdigit(*scan) || *scan == '.'; scan++) {
  76                 if (*scan == '.' && match_count == 0)
  77                         match_count = 1;
  78                 else if (*scan == '.' && match_count == 1)
  79                         return 0;
  80         }
  81
  82         if (*scan) {
  83                 match_count = 0;
  84                 for (unit = def_units; unit->str_unit; unit++) {
  85                         for (i = 0;
  86                              scan[i] && tolower(scan[i]) == unit->str_unit[i];
  87                              ++i)
  88                                 continue;
  89                         if (scan[i])
  90                                 continue;
  91                         match_count++;
  92                         power = unit->power_of_ten;
  93                 }
  94                 if (match_count != 1)
  95                         return 0;
  96         }
  97
  98         /* count the number of digits to be copied */
  99         for (cp = 0; isdigit(str[cp]); cp++)
 100                 continue;
 101
 102         if (str[cp] == '.') {
 103                 while (power > -1 && isdigit(str[cp+1]))
 104                         cp++, power--;
 105         }
 106         if (power >= -1)        /* not enough => pad */
 107                 pad = power + 1;
 108         else                    /* to much => strip */
 109                 pad = 0, cp += power + 1;
 110         /* check bounds */
 111         if (cp <= 0 || cp + pad > NORM_FREQ_LEN - 1)
 112                 return 0;
 113
 114         /* copy digits */
 115         for (i = 0; i < cp; i++, str++) {
 116                 if (*str == '.')
 117                         str++;
 118                 normalized[i] = *str;
 119         }
 120         /* and pad */
 121         for (; i < cp + pad; i++)
 122                 normalized[i] = '0';
 123
 124         /* round up, down ? */
 125         match_count = (normalized[i-1] >= '5');
 126         /* and drop the decimal part */
 127         normalized[i-1] = 0; /* cp > 0 && pad >= 0 ==> i > 0 */
 128
 129         /* final conversion (and applying rounding) */
 130         errno = 0;
 131         freq = strtoul(normalized, &end, 10);
 132         if (errno)
 133                 return 0;
 134         else {
 135                 if (match_count && freq != ULONG_MAX)
 136                         freq++;
 137                 return freq;
 138         }
 139 }
 140
 141 static int do_new_policy(unsigned int cpu, struct cpufreq_policy *new_pol)
 142 {
 143         struct cpufreq_policy *cur_pol = cpufreq_get_policy(cpu);
 144         int ret;
 145
 146         if (!cur_pol) {
 147                 printf(_("wrong, unknown or unhandled CPU?\n"));
 148                 return -EINVAL;
 149         }
 150
 151         if (!new_pol->min)
 152                 new_pol->min = cur_pol->min;
 153
 154         if (!new_pol->max)
 155                 new_pol->max = cur_pol->max;
 156
 157         if (!new_pol->governor)
 158                 new_pol->governor = cur_pol->governor;
 159
 160         ret = cpufreq_set_policy(cpu, new_pol);
 161
 162         cpufreq_put_policy(cur_pol);
 163
 164         return ret;
 165 }
 166
 167
 168 static int do_one_cpu(unsigned int cpu, struct cpufreq_policy *new_pol,
 169                 unsigned long freq, unsigned int pc)
 170 {
 171         switch (pc) {
 172         case 0:
 173                 return cpufreq_set_frequency(cpu, freq);
 174
 175         case 1:
 176                 /* if only one value of a policy is to be changed, we can
 177                  * use a "fast path".
 178                  */
 179                 if (new_pol->min)
 180                         return cpufreq_modify_policy_min(cpu, new_pol->min);
 181                 else if (new_pol->max)
 182                         return cpufreq_modify_policy_max(cpu, new_pol->max);
 183                 else if (new_pol->governor)
 184                         return cpufreq_modify_policy_governor(cpu,
 185                                                         new_pol->governor);
 186
 187         default:
 188                 /* slow path */
 189                 return do_new_policy(cpu, new_pol);
 190         }
 191 }
 192
 193 int cmd_freq_set(int argc, char **argv)
 194 {
 195         extern char *optarg;
 196         extern int optind, opterr, optopt;
 197         int ret = 0, cont = 1;
 198         int double_parm = 0, related = 0, policychange = 0;
 199         unsigned long freq = 0;
 200         char gov[20];
 201         unsigned int cpu;
 202
 203         struct cpufreq_policy new_pol = {
 204                 .min = 0,
 205                 .max = 0,
 206                 .governor = NULL,
 207         };
 208
 209         /* parameter parsing */
 210         do {
 211                 ret = getopt_long(argc, argv, "d:u:g:f:r", set_opts, NULL);
 212                 switch (ret) {
 213                 case '?':
 214                         print_unknown_arg();
 215                         return -EINVAL;
 216                 case -1:
 217                         cont = 0;
 218                         break;
 219                 case 'r':
 220                         if (related)
 221                                 double_parm++;
 222                         related++;
 223                         break;
 224                 case 'd':
 225                         if (new_pol.min)
 226                                 double_parm++;
 227                         policychange++;
 228                         new_pol.min = string_to_frequency(optarg);
 229                         if (new_pol.min == 0) {
 230                                 print_unknown_arg();
 231                                 return -EINVAL;
 232                         }
 233                         break;
 234                 case 'u':
 235                         if (new_pol.max)
 236                                 double_parm++;
 237                         policychange++;
 238                         new_pol.max = string_to_frequency(optarg);
 239                         if (new_pol.max == 0) {
 240                                 print_unknown_arg();
 241                                 return -EINVAL;
 242                         }
 243                         break;
 244                 case 'f':
 245                         if (freq)
 246                                 double_parm++;
 247                         freq = string_to_frequency(optarg);
 248                         if (freq == 0) {
 249                                 print_unknown_arg();
 250                                 return -EINVAL;
 251                         }
 252                         break;
 253                 case 'g':
 254                         if (new_pol.governor)
 255                                 double_parm++;
 256                         policychange++;
 257                         if ((strlen(optarg) < 3) || (strlen(optarg) > 18)) {
 258                                 print_unknown_arg();
 259                                 return -EINVAL;
 260                         }
 261                         if ((sscanf(optarg, "%19s", gov)) != 1) {
 262                                 print_unknown_arg();
 263                                 return -EINVAL;
 264                         }
 265                         new_pol.governor = gov;
 266                         break;
 267                 }
 268         } while (cont);
 269
 270         /* parameter checking */
 271         if (double_parm) {
 272                 printf("the same parameter was passed more than once\n");
 273                 return -EINVAL;
 274         }
 275
 276         if (freq && policychange) {
 277                 printf(_("the -f/--freq parameter cannot be combined with -d/--min, -u/--max or\n"
 278                                 "-g/--governor parameters\n"));
 279                 return -EINVAL;
 280         }
 281
 282         if (!freq && !policychange) {
 283                 printf(_("At least one parameter out of -f/--freq, -d/--min, -u/--max, and\n"
 284                                 "-g/--governor must be passed\n"));
 285                 return -EINVAL;
 286         }
 287
 288         /* Default is: set all CPUs */
 289         if (bitmask_isallclear(cpus_chosen))
 290                 bitmask_setall(cpus_chosen);
 291
 292         /* Also set frequency settings for related CPUs if -r is passed */
 293         if (related) {
 294                 for (cpu = bitmask_first(cpus_chosen);
 295                      cpu <= bitmask_last(cpus_chosen); cpu++) {
 296                         struct cpufreq_affected_cpus *cpus;
 297
 298                         if (!bitmask_isbitset(cpus_chosen, cpu) ||
 299                             cpufreq_cpu_exists(cpu))
 300                                 continue;
 301
 302                         cpus = cpufreq_get_related_cpus(cpu);
 303                         if (!cpus)
 304                                 break;
 305                         while (cpus->next) {
 306                                 bitmask_setbit(cpus_chosen, cpus->cpu);
 307                                 cpus = cpus->next;
 308                         }
 309                         cpufreq_put_related_cpus(cpus);
 310                 }
 311         }
 312
 313
 314         /* loop over CPUs */
 315         for (cpu = bitmask_first(cpus_chosen);
 316              cpu <= bitmask_last(cpus_chosen); cpu++) {
 317
 318                 if (!bitmask_isbitset(cpus_chosen, cpu) ||
 319                     cpufreq_cpu_exists(cpu))
 320                         continue;
 321
 322                 if (sysfs_is_cpu_online(cpu) != 1)
 323                         continue;
 324
 325                 printf(_("Setting cpu: %d\n"), cpu);
 326                 ret = do_one_cpu(cpu, &new_pol, freq, policychange);
 327                 if (ret) {
 328                         print_error();
 329                         return ret;
 330                 }
 331         }
 332
 333         return 0;
 334 }