drivers/cpufreq/freq_table.c

   1 /*
   2  * linux/drivers/cpufreq/freq_table.c
   3  *
   4  * Copyright (C) 2002 - 2003 Dominik Brodowski
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  *
  10  */
  11
  12 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  13
  14 #include <linux/cpufreq.h>
  15 #include <linux/module.h>
  16
  17 /*********************************************************************
  18  *                     FREQUENCY TABLE HELPERS                       *
  19  *********************************************************************/
  20
  21 int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
  22                                     struct cpufreq_frequency_table *table)
  23 {
  24         unsigned int min_freq = ~0;
  25         unsigned int max_freq = 0;
  26         unsigned int i;
  27
  28         for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
  29                 unsigned int freq = table[i].frequency;
  30                 if (freq == CPUFREQ_ENTRY_INVALID) {
  31                         pr_debug("table entry %u is invalid, skipping\n", i);
  32
  33                         continue;
  34                 }
  35                 if (!cpufreq_boost_enabled()
  36                     && table[i].driver_data == CPUFREQ_BOOST_FREQ)
  37                         continue;
  38
  39                 pr_debug("table entry %u: %u kHz, %u driver_data\n",
  40                                         i, freq, table[i].driver_data);
  41                 if (freq < min_freq)
  42                         min_freq = freq;
  43                 if (freq > max_freq)
  44                         max_freq = freq;
  45         }
  46
  47         policy->min = policy->cpuinfo.min_freq = min_freq;
  48         policy->max = policy->cpuinfo.max_freq = max_freq;
  49
  50         if (policy->min == ~0)
  51                 return -EINVAL;
  52         else
  53                 return 0;
  54 }
  55 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_cpuinfo);
  56
  57
  58 int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
  59                                    struct cpufreq_frequency_table *table)
  60 {
  61         unsigned int next_larger = ~0, freq, i = 0;
  62         bool found = false;
  63
  64         pr_debug("request for verification of policy (%u - %u kHz) for cpu %u\n",
  65                                         policy->min, policy->max, policy->cpu);
  66
  67         cpufreq_verify_within_cpu_limits(policy);
  68
  69         for (; freq = table[i].frequency, freq != CPUFREQ_TABLE_END; i++) {
  70                 if (freq == CPUFREQ_ENTRY_INVALID)
  71                         continue;
  72                 if ((freq >= policy->min) && (freq <= policy->max)) {
  73                         found = true;
  74                         break;
  75                 }
  76
  77                 if ((next_larger > freq) && (freq > policy->max))
  78                         next_larger = freq;
  79         }
  80
  81         if (!found) {
  82                 policy->max = next_larger;
  83                 cpufreq_verify_within_cpu_limits(policy);
  84         }
  85
  86         pr_debug("verification lead to (%u - %u kHz) for cpu %u\n",
  87                                 policy->min, policy->max, policy->cpu);
  88
  89         return 0;
  90 }
  91 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_verify);
  92
  93 /*
  94  * Generic routine to verify policy & frequency table, requires driver to call
  95  * cpufreq_frequency_table_get_attr() prior to it.
  96  */
  97 int cpufreq_generic_frequency_table_verify(struct cpufreq_policy *policy)
  98 {
  99         struct cpufreq_frequency_table *table =
 100                 cpufreq_frequency_get_table(policy->cpu);
 101         if (!table)
 102                 return -ENODEV;
 103
 104         return cpufreq_frequency_table_verify(policy, table);
 105 }
 106 EXPORT_SYMBOL_GPL(cpufreq_generic_frequency_table_verify);
 107
 108 int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
 109                                    struct cpufreq_frequency_table *table,
 110                                    unsigned int target_freq,
 111                                    unsigned int relation,
 112                                    unsigned int *index)
 113 {
 114         struct cpufreq_frequency_table optimal = {
 115                 .driver_data = ~0,
 116                 .frequency = 0,
 117         };
 118         struct cpufreq_frequency_table suboptimal = {
 119                 .driver_data = ~0,
 120                 .frequency = 0,
 121         };
 122         unsigned int i;
 123
 124         pr_debug("request for target %u kHz (relation: %u) for cpu %u\n",
 125                                         target_freq, relation, policy->cpu);
 126
 127         switch (relation) {
 128         case CPUFREQ_RELATION_H:
 129                 suboptimal.frequency = ~0;
 130                 break;
 131         case CPUFREQ_RELATION_L:
 132                 optimal.frequency = ~0;
 133                 break;
 134         }
 135
 136         for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
 137                 unsigned int freq = table[i].frequency;
 138                 if (freq == CPUFREQ_ENTRY_INVALID)
 139                         continue;
 140                 if ((freq < policy->min) || (freq > policy->max))
 141                         continue;
 142                 switch (relation) {
 143                 case CPUFREQ_RELATION_H:
 144                         if (freq <= target_freq) {
 145                                 if (freq >= optimal.frequency) {
 146                                         optimal.frequency = freq;
 147                                         optimal.driver_data = i;
 148                                 }
 149                         } else {
 150                                 if (freq <= suboptimal.frequency) {
 151                                         suboptimal.frequency = freq;
 152                                         suboptimal.driver_data = i;
 153                                 }
 154                         }
 155                         break;
 156                 case CPUFREQ_RELATION_L:
 157                         if (freq >= target_freq) {
 158                                 if (freq <= optimal.frequency) {
 159                                         optimal.frequency = freq;
 160                                         optimal.driver_data = i;
 161                                 }
 162                         } else {
 163                                 if (freq >= suboptimal.frequency) {
 164                                         suboptimal.frequency = freq;
 165                                         suboptimal.driver_data = i;
 166                                 }
 167                         }
 168                         break;
 169                 }
 170         }
 171         if (optimal.driver_data > i) {
 172                 if (suboptimal.driver_data > i)
 173                         return -EINVAL;
 174                 *index = suboptimal.driver_data;
 175         } else
 176                 *index = optimal.driver_data;
 177
 178         pr_debug("target is %u (%u kHz, %u)\n", *index, table[*index].frequency,
 179                 table[*index].driver_data);
 180
 181         return 0;
 182 }
 183 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_target);
 184
 185 int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy,
 186                 unsigned int freq)
 187 {
 188         struct cpufreq_frequency_table *table;
 189         int i;
 190
 191         table = cpufreq_frequency_get_table(policy->cpu);
 192         if (unlikely(!table)) {
 193                 pr_debug("%s: Unable to find frequency table\n", __func__);
 194                 return -ENOENT;
 195         }
 196
 197         for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) {
 198                 if (table[i].frequency == freq)
 199                         return i;
 200         }
 201
 202         return -EINVAL;
 203 }
 204 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_get_index);
 205
 206 static DEFINE_PER_CPU(struct cpufreq_frequency_table *, cpufreq_show_table);
 207
 208 /**
 209  * show_available_freqs - show available frequencies for the specified CPU
 210  */
 211 static ssize_t show_available_freqs(struct cpufreq_policy *policy, char *buf,
 212                                     bool show_boost)
 213 {
 214         unsigned int i = 0;
 215         unsigned int cpu = policy->cpu;
 216         ssize_t count = 0;
 217         struct cpufreq_frequency_table *table;
 218
 219         if (!per_cpu(cpufreq_show_table, cpu))
 220                 return -ENODEV;
 221
 222         table = per_cpu(cpufreq_show_table, cpu);
 223
 224         for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
 225                 if (table[i].frequency == CPUFREQ_ENTRY_INVALID)
 226                         continue;
 227                 /*
 228                  * show_boost = true and driver_data = BOOST freq
 229                  * display BOOST freqs
 230                  *
 231                  * show_boost = false and driver_data = BOOST freq
 232                  * show_boost = true and driver_data != BOOST freq
 233                  * continue - do not display anything
 234                  *
 235                  * show_boost = false and driver_data != BOOST freq
 236                  * display NON BOOST freqs
 237                  */
 238                 if (show_boost ^ (table[i].driver_data == CPUFREQ_BOOST_FREQ))
 239                         continue;
 240
 241                 count += sprintf(&buf[count], "%d ", table[i].frequency);
 242         }
 243         count += sprintf(&buf[count], "\n");
 244
 245         return count;
 246
 247 }
 248
 249 #define cpufreq_attr_available_freq(_name)        \
 250 struct freq_attr cpufreq_freq_attr_##_name##_freqs =     \
 251 __ATTR_RO(_name##_frequencies)
 252
 253 /**
 254  * show_scaling_available_frequencies - show available normal frequencies for
 255  * the specified CPU
 256  */
 257 static ssize_t scaling_available_frequencies_show(struct cpufreq_policy *policy,
 258                                                   char *buf)
 259 {
 260         return show_available_freqs(policy, buf, false);
 261 }
 262 cpufreq_attr_available_freq(scaling_available);
 263 EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_available_freqs);
 264
 265 /**
 266  * show_available_boost_freqs - show available boost frequencies for
 267  * the specified CPU
 268  */
 269 static ssize_t scaling_boost_frequencies_show(struct cpufreq_policy *policy,
 270                                               char *buf)
 271 {
 272         return show_available_freqs(policy, buf, true);
 273 }
 274 cpufreq_attr_available_freq(scaling_boost);
 275 EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_boost_freqs);
 276
 277 struct freq_attr *cpufreq_generic_attr[] = {
 278         &cpufreq_freq_attr_scaling_available_freqs,
 279 #ifdef CONFIG_CPU_FREQ_BOOST_SW
 280         &cpufreq_freq_attr_scaling_boost_freqs,
 281 #endif
 282         NULL,
 283 };
 284 EXPORT_SYMBOL_GPL(cpufreq_generic_attr);
 285
 286 /*
 287  * if you use these, you must assure that the frequency table is valid
 288  * all the time between get_attr and put_attr!
 289  */
 290 void cpufreq_frequency_table_get_attr(struct cpufreq_frequency_table *table,
 291                                       unsigned int cpu)
 292 {
 293         pr_debug("setting show_table for cpu %u to %p\n", cpu, table);
 294         per_cpu(cpufreq_show_table, cpu) = table;
 295 }
 296 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_get_attr);
 297
 298 void cpufreq_frequency_table_put_attr(unsigned int cpu)
 299 {
 300         pr_debug("clearing show_table for cpu %u\n", cpu);
 301         per_cpu(cpufreq_show_table, cpu) = NULL;
 302 }
 303 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_put_attr);
 304
 305 int cpufreq_table_validate_and_show(struct cpufreq_policy *policy,
 306                                       struct cpufreq_frequency_table *table)
 307 {
 308         int ret = cpufreq_frequency_table_cpuinfo(policy, table);
 309
 310         if (!ret)
 311                 cpufreq_frequency_table_get_attr(table, policy->cpu);
 312
 313         return ret;
 314 }
 315 EXPORT_SYMBOL_GPL(cpufreq_table_validate_and_show);
 316
 317 void cpufreq_frequency_table_update_policy_cpu(struct cpufreq_policy *policy)
 318 {
 319         pr_debug("Updating show_table for new_cpu %u from last_cpu %u\n",
 320                         policy->cpu, policy->last_cpu);
 321         per_cpu(cpufreq_show_table, policy->cpu) = per_cpu(cpufreq_show_table,
 322                         policy->last_cpu);
 323         per_cpu(cpufreq_show_table, policy->last_cpu) = NULL;
 324 }
 325
 326 struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu)
 327 {
 328         return per_cpu(cpufreq_show_table, cpu);
 329 }
 330 EXPORT_SYMBOL_GPL(cpufreq_frequency_get_table);
 331
 332 MODULE_AUTHOR("Dominik Brodowski <linux@brodo.de>");
 333 MODULE_DESCRIPTION("CPUfreq frequency table helpers");
 334 MODULE_LICENSE("GPL");