1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * linux/drivers/cpufreq/freq_table.c 4 * 5 * Copyright (C) 2002 - 2003 Dominik Brodowski 6 */ 7 8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 9 10 #include <linux/cpufreq.h> 11 #include <linux/module.h> 12 13 /********************************************************************* 14 * FREQUENCY TABLE HELPERS * 15 *********************************************************************/ 16 17 bool policy_has_boost_freq(struct cpufreq_policy *policy) 18 { 19 struct cpufreq_frequency_table *pos, *table = policy->freq_table; 20 21 if (!table) 22 return false; 23 24 cpufreq_for_each_valid_entry(pos, table) 25 if (pos->flags & CPUFREQ_BOOST_FREQ) 26 return true; 27 28 return false; 29 } 30 EXPORT_SYMBOL_GPL(policy_has_boost_freq); 31 32 int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy, 33 struct cpufreq_frequency_table *table) 34 { 35 struct cpufreq_frequency_table *pos; 36 unsigned int min_freq = ~0; 37 unsigned int max_freq = 0; 38 unsigned int freq; 39 40 cpufreq_for_each_valid_entry(pos, table) { 41 freq = pos->frequency; 42 43 if (!cpufreq_boost_enabled() 44 && (pos->flags & CPUFREQ_BOOST_FREQ)) 45 continue; 46 47 pr_debug("table entry %u: %u kHz\n", (int)(pos - table), freq); 48 if (freq < min_freq) 49 min_freq = freq; 50 if (freq > max_freq) 51 max_freq = freq; 52 } 53 54 policy->min = policy->cpuinfo.min_freq = min_freq; 55 policy->max = policy->cpuinfo.max_freq = max_freq; 56 57 if (policy->min == ~0) 58 return -EINVAL; 59 else 60 return 0; 61 } 62 63 int cpufreq_frequency_table_verify(struct cpufreq_policy *policy, 64 struct cpufreq_frequency_table *table) 65 { 66 struct cpufreq_frequency_table *pos; 67 unsigned int freq, next_larger = ~0; 68 bool found = false; 69 70 pr_debug("request for verification of policy (%u - %u kHz) for cpu %u\n", 71 policy->min, policy->max, policy->cpu); 72 73 cpufreq_verify_within_cpu_limits(policy); 74 75 cpufreq_for_each_valid_entry(pos, table) { 76 freq = pos->frequency; 77 78 if ((freq >= policy->min) && (freq <= policy->max)) { 79 found = true; 80 break; 81 } 82 83 if ((next_larger > freq) && (freq > policy->max)) 84 next_larger = freq; 85 } 86 87 if (!found) { 88 policy->max = next_larger; 89 cpufreq_verify_within_cpu_limits(policy); 90 } 91 92 pr_debug("verification lead to (%u - %u kHz) for cpu %u\n", 93 policy->min, policy->max, policy->cpu); 94 95 return 0; 96 } 97 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_verify); 98 99 /* 100 * Generic routine to verify policy & frequency table, requires driver to set 101 * policy->freq_table prior to it. 102 */ 103 int cpufreq_generic_frequency_table_verify(struct cpufreq_policy *policy) 104 { 105 if (!policy->freq_table) 106 return -ENODEV; 107 108 return cpufreq_frequency_table_verify(policy, policy->freq_table); 109 } 110 EXPORT_SYMBOL_GPL(cpufreq_generic_frequency_table_verify); 111 112 int cpufreq_table_index_unsorted(struct cpufreq_policy *policy, 113 unsigned int target_freq, 114 unsigned int relation) 115 { 116 struct cpufreq_frequency_table optimal = { 117 .driver_data = ~0, 118 .frequency = 0, 119 }; 120 struct cpufreq_frequency_table suboptimal = { 121 .driver_data = ~0, 122 .frequency = 0, 123 }; 124 struct cpufreq_frequency_table *pos; 125 struct cpufreq_frequency_table *table = policy->freq_table; 126 unsigned int freq, diff, i = 0; 127 int index; 128 129 pr_debug("request for target %u kHz (relation: %u) for cpu %u\n", 130 target_freq, relation, policy->cpu); 131 132 switch (relation) { 133 case CPUFREQ_RELATION_H: 134 suboptimal.frequency = ~0; 135 break; 136 case CPUFREQ_RELATION_L: 137 case CPUFREQ_RELATION_C: 138 optimal.frequency = ~0; 139 break; 140 } 141 142 cpufreq_for_each_valid_entry_idx(pos, table, i) { 143 freq = pos->frequency; 144 145 if ((freq < policy->min) || (freq > policy->max)) 146 continue; 147 if (freq == target_freq) { 148 optimal.driver_data = i; 149 break; 150 } 151 switch (relation) { 152 case CPUFREQ_RELATION_H: 153 if (freq < target_freq) { 154 if (freq >= optimal.frequency) { 155 optimal.frequency = freq; 156 optimal.driver_data = i; 157 } 158 } else { 159 if (freq <= suboptimal.frequency) { 160 suboptimal.frequency = freq; 161 suboptimal.driver_data = i; 162 } 163 } 164 break; 165 case CPUFREQ_RELATION_L: 166 if (freq > target_freq) { 167 if (freq <= optimal.frequency) { 168 optimal.frequency = freq; 169 optimal.driver_data = i; 170 } 171 } else { 172 if (freq >= suboptimal.frequency) { 173 suboptimal.frequency = freq; 174 suboptimal.driver_data = i; 175 } 176 } 177 break; 178 case CPUFREQ_RELATION_C: 179 diff = abs(freq - target_freq); 180 if (diff < optimal.frequency || 181 (diff == optimal.frequency && 182 freq > table[optimal.driver_data].frequency)) { 183 optimal.frequency = diff; 184 optimal.driver_data = i; 185 } 186 break; 187 } 188 } 189 if (optimal.driver_data > i) { 190 if (suboptimal.driver_data > i) { 191 WARN(1, "Invalid frequency table: %d\n", policy->cpu); 192 return 0; 193 } 194 195 index = suboptimal.driver_data; 196 } else 197 index = optimal.driver_data; 198 199 pr_debug("target index is %u, freq is:%u kHz\n", index, 200 table[index].frequency); 201 return index; 202 } 203 EXPORT_SYMBOL_GPL(cpufreq_table_index_unsorted); 204 205 int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy, 206 unsigned int freq) 207 { 208 struct cpufreq_frequency_table *pos, *table = policy->freq_table; 209 int idx; 210 211 if (unlikely(!table)) { 212 pr_debug("%s: Unable to find frequency table\n", __func__); 213 return -ENOENT; 214 } 215 216 cpufreq_for_each_valid_entry_idx(pos, table, idx) 217 if (pos->frequency == freq) 218 return idx; 219 220 return -EINVAL; 221 } 222 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_get_index); 223 224 /** 225 * show_available_freqs - show available frequencies for the specified CPU 226 */ 227 static ssize_t show_available_freqs(struct cpufreq_policy *policy, char *buf, 228 bool show_boost) 229 { 230 ssize_t count = 0; 231 struct cpufreq_frequency_table *pos, *table = policy->freq_table; 232 233 if (!table) 234 return -ENODEV; 235 236 cpufreq_for_each_valid_entry(pos, table) { 237 /* 238 * show_boost = true and driver_data = BOOST freq 239 * display BOOST freqs 240 * 241 * show_boost = false and driver_data = BOOST freq 242 * show_boost = true and driver_data != BOOST freq 243 * continue - do not display anything 244 * 245 * show_boost = false and driver_data != BOOST freq 246 * display NON BOOST freqs 247 */ 248 if (show_boost ^ (pos->flags & CPUFREQ_BOOST_FREQ)) 249 continue; 250 251 count += sprintf(&buf[count], "%d ", pos->frequency); 252 } 253 count += sprintf(&buf[count], "\n"); 254 255 return count; 256 257 } 258 259 #define cpufreq_attr_available_freq(_name) \ 260 struct freq_attr cpufreq_freq_attr_##_name##_freqs = \ 261 __ATTR_RO(_name##_frequencies) 262 263 /** 264 * show_scaling_available_frequencies - show available normal frequencies for 265 * the specified CPU 266 */ 267 static ssize_t scaling_available_frequencies_show(struct cpufreq_policy *policy, 268 char *buf) 269 { 270 return show_available_freqs(policy, buf, false); 271 } 272 cpufreq_attr_available_freq(scaling_available); 273 EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_available_freqs); 274 275 /** 276 * show_available_boost_freqs - show available boost frequencies for 277 * the specified CPU 278 */ 279 static ssize_t scaling_boost_frequencies_show(struct cpufreq_policy *policy, 280 char *buf) 281 { 282 return show_available_freqs(policy, buf, true); 283 } 284 cpufreq_attr_available_freq(scaling_boost); 285 EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_boost_freqs); 286 287 struct freq_attr *cpufreq_generic_attr[] = { 288 &cpufreq_freq_attr_scaling_available_freqs, 289 NULL, 290 }; 291 EXPORT_SYMBOL_GPL(cpufreq_generic_attr); 292 293 static int set_freq_table_sorted(struct cpufreq_policy *policy) 294 { 295 struct cpufreq_frequency_table *pos, *table = policy->freq_table; 296 struct cpufreq_frequency_table *prev = NULL; 297 int ascending = 0; 298 299 policy->freq_table_sorted = CPUFREQ_TABLE_UNSORTED; 300 301 cpufreq_for_each_valid_entry(pos, table) { 302 if (!prev) { 303 prev = pos; 304 continue; 305 } 306 307 if (pos->frequency == prev->frequency) { 308 pr_warn("Duplicate freq-table entries: %u\n", 309 pos->frequency); 310 return -EINVAL; 311 } 312 313 /* Frequency increased from prev to pos */ 314 if (pos->frequency > prev->frequency) { 315 /* But frequency was decreasing earlier */ 316 if (ascending < 0) { 317 pr_debug("Freq table is unsorted\n"); 318 return 0; 319 } 320 321 ascending++; 322 } else { 323 /* Frequency decreased from prev to pos */ 324 325 /* But frequency was increasing earlier */ 326 if (ascending > 0) { 327 pr_debug("Freq table is unsorted\n"); 328 return 0; 329 } 330 331 ascending--; 332 } 333 334 prev = pos; 335 } 336 337 if (ascending > 0) 338 policy->freq_table_sorted = CPUFREQ_TABLE_SORTED_ASCENDING; 339 else 340 policy->freq_table_sorted = CPUFREQ_TABLE_SORTED_DESCENDING; 341 342 pr_debug("Freq table is sorted in %s order\n", 343 ascending > 0 ? "ascending" : "descending"); 344 345 return 0; 346 } 347 348 int cpufreq_table_validate_and_sort(struct cpufreq_policy *policy) 349 { 350 int ret; 351 352 if (!policy->freq_table) 353 return 0; 354 355 ret = cpufreq_frequency_table_cpuinfo(policy, policy->freq_table); 356 if (ret) 357 return ret; 358 359 return set_freq_table_sorted(policy); 360 } 361 362 MODULE_AUTHOR("Dominik Brodowski <linux@brodo.de>"); 363 MODULE_DESCRIPTION("CPUfreq frequency table helpers"); 364 MODULE_LICENSE("GPL"); 365