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].flags & CPUFREQ_BOOST_FREQ))
  37                         continue;
  38
  39                 pr_debug("table entry %u: %u kHz\n", i, freq);
  40                 if (freq < min_freq)
  41                         min_freq = freq;
  42                 if (freq > max_freq)
  43                         max_freq = freq;
  44         }
  45
  46         policy->min = policy->cpuinfo.min_freq = min_freq;
  47         policy->max = policy->cpuinfo.max_freq = max_freq;
  48
  49         if (policy->min == ~0)
  50                 return -EINVAL;
  51         else
  52                 return 0;
  53 }
  54 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_cpuinfo);
  55
  56
  57 int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
  58                                    struct cpufreq_frequency_table *table)
  59 {
  60         unsigned int next_larger = ~0, freq, i = 0;
  61         bool found = false;
  62
  63         pr_debug("request for verification of policy (%u - %u kHz) for cpu %u\n",
  64                                         policy->min, policy->max, policy->cpu);
  65
  66         cpufreq_verify_within_cpu_limits(policy);
  67
  68         for (; freq = table[i].frequency, freq != CPUFREQ_TABLE_END; i++) {
  69                 if (freq == CPUFREQ_ENTRY_INVALID)
  70                         continue;
  71                 if ((freq >= policy->min) && (freq <= policy->max)) {
  72                         found = true;
  73                         break;
  74                 }
  75
  76                 if ((next_larger > freq) && (freq > policy->max))
  77                         next_larger = freq;
  78         }
  79
  80         if (!found) {
  81                 policy->max = next_larger;
  82                 cpufreq_verify_within_cpu_limits(policy);
  83         }
  84
  85         pr_debug("verification lead to (%u - %u kHz) for cpu %u\n",
  86                                 policy->min, policy->max, policy->cpu);
  87
  88         return 0;
  89 }
  90 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_verify);
  91
  92 /*
  93  * Generic routine to verify policy & frequency table, requires driver to set
  94  * policy->freq_table prior to it.
  95  */
  96 int cpufreq_generic_frequency_table_verify(struct cpufreq_policy *policy)
  97 {
  98         struct cpufreq_frequency_table *table =
  99                 cpufreq_frequency_get_table(policy->cpu);
 100         if (!table)
 101                 return -ENODEV;
 102
 103         return cpufreq_frequency_table_verify(policy, table);
 104 }
 105 EXPORT_SYMBOL_GPL(cpufreq_generic_frequency_table_verify);
 106
 107 int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
 108                                    struct cpufreq_frequency_table *table,
 109                                    unsigned int target_freq,
 110                                    unsigned int relation,
 111                                    unsigned int *index)
 112 {
 113         struct cpufreq_frequency_table optimal = {
 114                 .driver_data = ~0,
 115                 .frequency = 0,
 116         };
 117         struct cpufreq_frequency_table suboptimal = {
 118                 .driver_data = ~0,
 119                 .frequency = 0,
 120         };
 121         unsigned int i;
 122
 123         pr_debug("request for target %u kHz (relation: %u) for cpu %u\n",
 124                                         target_freq, relation, policy->cpu);
 125
 126         switch (relation) {
 127         case CPUFREQ_RELATION_H:
 128                 suboptimal.frequency = ~0;
 129                 break;
 130         case CPUFREQ_RELATION_L:
 131                 optimal.frequency = ~0;
 132                 break;
 133         }
 134
 135         for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
 136                 unsigned int freq = table[i].frequency;
 137                 if (freq == CPUFREQ_ENTRY_INVALID)
 138                         continue;
 139                 if ((freq < policy->min) || (freq > policy->max))
 140                         continue;
 141                 switch (relation) {
 142                 case CPUFREQ_RELATION_H:
 143                         if (freq <= target_freq) {
 144                                 if (freq >= optimal.frequency) {
 145                                         optimal.frequency = freq;
 146                                         optimal.driver_data = i;
 147                                 }
 148                         } else {
 149                                 if (freq <= suboptimal.frequency) {
 150                                         suboptimal.frequency = freq;
 151                                         suboptimal.driver_data = i;
 152                                 }
 153                         }
 154                         break;
 155                 case CPUFREQ_RELATION_L:
 156                         if (freq >= target_freq) {
 157                                 if (freq <= optimal.frequency) {
 158                                         optimal.frequency = freq;
 159                                         optimal.driver_data = i;
 160                                 }
 161                         } else {
 162                                 if (freq >= suboptimal.frequency) {
 163                                         suboptimal.frequency = freq;
 164                                         suboptimal.driver_data = i;
 165                                 }
 166                         }
 167                         break;
 168                 }
 169         }
 170         if (optimal.driver_data > i) {
 171                 if (suboptimal.driver_data > i)
 172                         return -EINVAL;
 173                 *index = suboptimal.driver_data;
 174         } else
 175                 *index = optimal.driver_data;
 176
 177         pr_debug("target index is %u, freq is:%u kHz\n", *index,
 178                  table[*index].frequency);
 179
 180         return 0;
 181 }
 182 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_target);
 183
 184 int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy,
 185                 unsigned int freq)
 186 {
 187         struct cpufreq_frequency_table *table;
 188         int i;
 189
 190         table = cpufreq_frequency_get_table(policy->cpu);
 191         if (unlikely(!table)) {
 192                 pr_debug("%s: Unable to find frequency table\n", __func__);
 193                 return -ENOENT;
 194         }
 195
 196         for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) {
 197                 if (table[i].frequency == freq)
 198                         return i;
 199         }
 200
 201         return -EINVAL;
 202 }
 203 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_get_index);
 204
 205 /**
 206  * show_available_freqs - show available frequencies for the specified CPU
 207  */
 208 static ssize_t show_available_freqs(struct cpufreq_policy *policy, char *buf,
 209                                     bool show_boost)
 210 {
 211         unsigned int i = 0;
 212         ssize_t count = 0;
 213         struct cpufreq_frequency_table *table = policy->freq_table;
 214
 215         if (!table)
 216                 return -ENODEV;
 217
 218         for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
 219                 if (table[i].frequency == CPUFREQ_ENTRY_INVALID)
 220                         continue;
 221                 /*
 222                  * show_boost = true and driver_data = BOOST freq
 223                  * display BOOST freqs
 224                  *
 225                  * show_boost = false and driver_data = BOOST freq
 226                  * show_boost = true and driver_data != BOOST freq
 227                  * continue - do not display anything
 228                  *
 229                  * show_boost = false and driver_data != BOOST freq
 230                  * display NON BOOST freqs
 231                  */
 232                 if (show_boost ^ (table[i].flags & CPUFREQ_BOOST_FREQ))
 233                         continue;
 234
 235                 count += sprintf(&buf[count], "%d ", table[i].frequency);
 236         }
 237         count += sprintf(&buf[count], "\n");
 238
 239         return count;
 240
 241 }
 242
 243 #define cpufreq_attr_available_freq(_name)        \
 244 struct freq_attr cpufreq_freq_attr_##_name##_freqs =     \
 245 __ATTR_RO(_name##_frequencies)
 246
 247 /**
 248  * show_scaling_available_frequencies - show available normal frequencies for
 249  * the specified CPU
 250  */
 251 static ssize_t scaling_available_frequencies_show(struct cpufreq_policy *policy,
 252                                                   char *buf)
 253 {
 254         return show_available_freqs(policy, buf, false);
 255 }
 256 cpufreq_attr_available_freq(scaling_available);
 257 EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_available_freqs);
 258
 259 /**
 260  * show_available_boost_freqs - show available boost frequencies for
 261  * the specified CPU
 262  */
 263 static ssize_t scaling_boost_frequencies_show(struct cpufreq_policy *policy,
 264                                               char *buf)
 265 {
 266         return show_available_freqs(policy, buf, true);
 267 }
 268 cpufreq_attr_available_freq(scaling_boost);
 269 EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_boost_freqs);
 270
 271 struct freq_attr *cpufreq_generic_attr[] = {
 272         &cpufreq_freq_attr_scaling_available_freqs,
 273 #ifdef CONFIG_CPU_FREQ_BOOST_SW
 274         &cpufreq_freq_attr_scaling_boost_freqs,
 275 #endif
 276         NULL,
 277 };
 278 EXPORT_SYMBOL_GPL(cpufreq_generic_attr);
 279
 280 int cpufreq_table_validate_and_show(struct cpufreq_policy *policy,
 281                                       struct cpufreq_frequency_table *table)
 282 {
 283         int ret = cpufreq_frequency_table_cpuinfo(policy, table);
 284
 285         if (!ret)
 286                 policy->freq_table = table;
 287
 288         return ret;
 289 }
 290 EXPORT_SYMBOL_GPL(cpufreq_table_validate_and_show);
 291
 292 struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu);
 293
 294 struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu)
 295 {
 296         struct cpufreq_policy *policy = cpufreq_cpu_get_raw(cpu);
 297         return policy ? policy->freq_table : NULL;
 298 }
 299 EXPORT_SYMBOL_GPL(cpufreq_frequency_get_table);
 300
 301 MODULE_AUTHOR("Dominik Brodowski <linux@brodo.de>");
 302 MODULE_DESCRIPTION("CPUfreq frequency table helpers");
 303 MODULE_LICENSE("GPL");