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
policy_has_boost_freq(struct cpufreq_policy * policy)21 bool policy_has_boost_freq(struct cpufreq_policy *policy)
22 {
23 struct cpufreq_frequency_table *pos, *table = policy->freq_table;
24
25 if (!table)
26 return false;
27
28 cpufreq_for_each_valid_entry(pos, table)
29 if (pos->flags & CPUFREQ_BOOST_FREQ)
30 return true;
31
32 return false;
33 }
34 EXPORT_SYMBOL_GPL(policy_has_boost_freq);
35
cpufreq_frequency_table_cpuinfo(struct cpufreq_policy * policy,struct cpufreq_frequency_table * table)36 int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
37 struct cpufreq_frequency_table *table)
38 {
39 struct cpufreq_frequency_table *pos;
40 unsigned int min_freq = ~0;
41 unsigned int max_freq = 0;
42 unsigned int freq;
43
44 cpufreq_for_each_valid_entry(pos, table) {
45 freq = pos->frequency;
46
47 if (!cpufreq_boost_enabled()
48 && (pos->flags & CPUFREQ_BOOST_FREQ))
49 continue;
50
51 pr_debug("table entry %u: %u kHz\n", (int)(pos - table), freq);
52 if (freq < min_freq)
53 min_freq = freq;
54 if (freq > max_freq)
55 max_freq = freq;
56 }
57
58 policy->min = policy->cpuinfo.min_freq = min_freq;
59 policy->max = policy->cpuinfo.max_freq = max_freq;
60
61 if (policy->min == ~0)
62 return -EINVAL;
63 else
64 return 0;
65 }
66
cpufreq_frequency_table_verify(struct cpufreq_policy * policy,struct cpufreq_frequency_table * table)67 int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
68 struct cpufreq_frequency_table *table)
69 {
70 struct cpufreq_frequency_table *pos;
71 unsigned int freq, next_larger = ~0;
72 bool found = false;
73
74 pr_debug("request for verification of policy (%u - %u kHz) for cpu %u\n",
75 policy->min, policy->max, policy->cpu);
76
77 cpufreq_verify_within_cpu_limits(policy);
78
79 cpufreq_for_each_valid_entry(pos, table) {
80 freq = pos->frequency;
81
82 if ((freq >= policy->min) && (freq <= policy->max)) {
83 found = true;
84 break;
85 }
86
87 if ((next_larger > freq) && (freq > policy->max))
88 next_larger = freq;
89 }
90
91 if (!found) {
92 policy->max = next_larger;
93 cpufreq_verify_within_cpu_limits(policy);
94 }
95
96 pr_debug("verification lead to (%u - %u kHz) for cpu %u\n",
97 policy->min, policy->max, policy->cpu);
98
99 return 0;
100 }
101 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_verify);
102
103 /*
104 * Generic routine to verify policy & frequency table, requires driver to set
105 * policy->freq_table prior to it.
106 */
cpufreq_generic_frequency_table_verify(struct cpufreq_policy * policy)107 int cpufreq_generic_frequency_table_verify(struct cpufreq_policy *policy)
108 {
109 if (!policy->freq_table)
110 return -ENODEV;
111
112 return cpufreq_frequency_table_verify(policy, policy->freq_table);
113 }
114 EXPORT_SYMBOL_GPL(cpufreq_generic_frequency_table_verify);
115
cpufreq_table_index_unsorted(struct cpufreq_policy * policy,unsigned int target_freq,unsigned int relation)116 int cpufreq_table_index_unsorted(struct cpufreq_policy *policy,
117 unsigned int target_freq,
118 unsigned int relation)
119 {
120 struct cpufreq_frequency_table optimal = {
121 .driver_data = ~0,
122 .frequency = 0,
123 };
124 struct cpufreq_frequency_table suboptimal = {
125 .driver_data = ~0,
126 .frequency = 0,
127 };
128 struct cpufreq_frequency_table *pos;
129 struct cpufreq_frequency_table *table = policy->freq_table;
130 unsigned int freq, diff, i = 0;
131 int index;
132
133 pr_debug("request for target %u kHz (relation: %u) for cpu %u\n",
134 target_freq, relation, policy->cpu);
135
136 switch (relation) {
137 case CPUFREQ_RELATION_H:
138 suboptimal.frequency = ~0;
139 break;
140 case CPUFREQ_RELATION_L:
141 case CPUFREQ_RELATION_C:
142 optimal.frequency = ~0;
143 break;
144 }
145
146 cpufreq_for_each_valid_entry_idx(pos, table, i) {
147 freq = pos->frequency;
148
149 if ((freq < policy->min) || (freq > policy->max))
150 continue;
151 if (freq == target_freq) {
152 optimal.driver_data = i;
153 break;
154 }
155 switch (relation) {
156 case CPUFREQ_RELATION_H:
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 case CPUFREQ_RELATION_L:
170 if (freq > target_freq) {
171 if (freq <= optimal.frequency) {
172 optimal.frequency = freq;
173 optimal.driver_data = i;
174 }
175 } else {
176 if (freq >= suboptimal.frequency) {
177 suboptimal.frequency = freq;
178 suboptimal.driver_data = i;
179 }
180 }
181 break;
182 case CPUFREQ_RELATION_C:
183 diff = abs(freq - target_freq);
184 if (diff < optimal.frequency ||
185 (diff == optimal.frequency &&
186 freq > table[optimal.driver_data].frequency)) {
187 optimal.frequency = diff;
188 optimal.driver_data = i;
189 }
190 break;
191 }
192 }
193 if (optimal.driver_data > i) {
194 if (suboptimal.driver_data > i) {
195 WARN(1, "Invalid frequency table: %d\n", policy->cpu);
196 return 0;
197 }
198
199 index = suboptimal.driver_data;
200 } else
201 index = optimal.driver_data;
202
203 pr_debug("target index is %u, freq is:%u kHz\n", index,
204 table[index].frequency);
205 return index;
206 }
207 EXPORT_SYMBOL_GPL(cpufreq_table_index_unsorted);
208
cpufreq_frequency_table_get_index(struct cpufreq_policy * policy,unsigned int freq)209 int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy,
210 unsigned int freq)
211 {
212 struct cpufreq_frequency_table *pos, *table = policy->freq_table;
213 int idx;
214
215 if (unlikely(!table)) {
216 pr_debug("%s: Unable to find frequency table\n", __func__);
217 return -ENOENT;
218 }
219
220 cpufreq_for_each_valid_entry_idx(pos, table, idx)
221 if (pos->frequency == freq)
222 return idx;
223
224 return -EINVAL;
225 }
226 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_get_index);
227
228 /**
229 * show_available_freqs - show available frequencies for the specified CPU
230 */
show_available_freqs(struct cpufreq_policy * policy,char * buf,bool show_boost)231 static ssize_t show_available_freqs(struct cpufreq_policy *policy, char *buf,
232 bool show_boost)
233 {
234 ssize_t count = 0;
235 struct cpufreq_frequency_table *pos, *table = policy->freq_table;
236
237 if (!table)
238 return -ENODEV;
239
240 cpufreq_for_each_valid_entry(pos, table) {
241 /*
242 * show_boost = true and driver_data = BOOST freq
243 * display BOOST freqs
244 *
245 * show_boost = false and driver_data = BOOST freq
246 * show_boost = true and driver_data != BOOST freq
247 * continue - do not display anything
248 *
249 * show_boost = false and driver_data != BOOST freq
250 * display NON BOOST freqs
251 */
252 if (show_boost ^ (pos->flags & CPUFREQ_BOOST_FREQ))
253 continue;
254
255 count += sprintf(&buf[count], "%d ", pos->frequency);
256 }
257 count += sprintf(&buf[count], "\n");
258
259 return count;
260
261 }
262
263 #define cpufreq_attr_available_freq(_name) \
264 struct freq_attr cpufreq_freq_attr_##_name##_freqs = \
265 __ATTR_RO(_name##_frequencies)
266
267 /**
268 * show_scaling_available_frequencies - show available normal frequencies for
269 * the specified CPU
270 */
scaling_available_frequencies_show(struct cpufreq_policy * policy,char * buf)271 static ssize_t scaling_available_frequencies_show(struct cpufreq_policy *policy,
272 char *buf)
273 {
274 return show_available_freqs(policy, buf, false);
275 }
276 cpufreq_attr_available_freq(scaling_available);
277 EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_available_freqs);
278
279 /**
280 * show_available_boost_freqs - show available boost frequencies for
281 * the specified CPU
282 */
scaling_boost_frequencies_show(struct cpufreq_policy * policy,char * buf)283 static ssize_t scaling_boost_frequencies_show(struct cpufreq_policy *policy,
284 char *buf)
285 {
286 return show_available_freqs(policy, buf, true);
287 }
288 cpufreq_attr_available_freq(scaling_boost);
289 EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_boost_freqs);
290
291 struct freq_attr *cpufreq_generic_attr[] = {
292 &cpufreq_freq_attr_scaling_available_freqs,
293 #ifdef CONFIG_CPU_FREQ_BOOST_SW
294 &cpufreq_freq_attr_scaling_boost_freqs,
295 #endif
296 NULL,
297 };
298 EXPORT_SYMBOL_GPL(cpufreq_generic_attr);
299
set_freq_table_sorted(struct cpufreq_policy * policy)300 static int set_freq_table_sorted(struct cpufreq_policy *policy)
301 {
302 struct cpufreq_frequency_table *pos, *table = policy->freq_table;
303 struct cpufreq_frequency_table *prev = NULL;
304 int ascending = 0;
305
306 policy->freq_table_sorted = CPUFREQ_TABLE_UNSORTED;
307
308 cpufreq_for_each_valid_entry(pos, table) {
309 if (!prev) {
310 prev = pos;
311 continue;
312 }
313
314 if (pos->frequency == prev->frequency) {
315 pr_warn("Duplicate freq-table entries: %u\n",
316 pos->frequency);
317 return -EINVAL;
318 }
319
320 /* Frequency increased from prev to pos */
321 if (pos->frequency > prev->frequency) {
322 /* But frequency was decreasing earlier */
323 if (ascending < 0) {
324 pr_debug("Freq table is unsorted\n");
325 return 0;
326 }
327
328 ascending++;
329 } else {
330 /* Frequency decreased from prev to pos */
331
332 /* But frequency was increasing earlier */
333 if (ascending > 0) {
334 pr_debug("Freq table is unsorted\n");
335 return 0;
336 }
337
338 ascending--;
339 }
340
341 prev = pos;
342 }
343
344 if (ascending > 0)
345 policy->freq_table_sorted = CPUFREQ_TABLE_SORTED_ASCENDING;
346 else
347 policy->freq_table_sorted = CPUFREQ_TABLE_SORTED_DESCENDING;
348
349 pr_debug("Freq table is sorted in %s order\n",
350 ascending > 0 ? "ascending" : "descending");
351
352 return 0;
353 }
354
cpufreq_table_validate_and_sort(struct cpufreq_policy * policy)355 int cpufreq_table_validate_and_sort(struct cpufreq_policy *policy)
356 {
357 int ret;
358
359 if (!policy->freq_table)
360 return 0;
361
362 ret = cpufreq_frequency_table_cpuinfo(policy, policy->freq_table);
363 if (ret)
364 return ret;
365
366 return set_freq_table_sorted(policy);
367 }
368
369 MODULE_AUTHOR("Dominik Brodowski <linux@brodo.de>");
370 MODULE_DESCRIPTION("CPUfreq frequency table helpers");
371 MODULE_LICENSE("GPL");
372