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
cpufreq_frequency_table_cpuinfo(struct cpufreq_policy * policy,struct cpufreq_frequency_table * table)21 int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
22 struct cpufreq_frequency_table *table)
23 {
24 struct cpufreq_frequency_table *pos;
25 unsigned int min_freq = ~0;
26 unsigned int max_freq = 0;
27 unsigned int freq;
28
29 cpufreq_for_each_valid_entry(pos, table) {
30 freq = pos->frequency;
31
32 if (!cpufreq_boost_enabled()
33 && (pos->flags & CPUFREQ_BOOST_FREQ))
34 continue;
35
36 pr_debug("table entry %u: %u kHz\n", (int)(pos - table), freq);
37 if (freq < min_freq)
38 min_freq = freq;
39 if (freq > max_freq)
40 max_freq = freq;
41 }
42
43 policy->min = policy->cpuinfo.min_freq = min_freq;
44 policy->max = policy->cpuinfo.max_freq = max_freq;
45
46 if (policy->min == ~0)
47 return -EINVAL;
48 else
49 return 0;
50 }
51 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_cpuinfo);
52
53
cpufreq_frequency_table_verify(struct cpufreq_policy * policy,struct cpufreq_frequency_table * table)54 int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
55 struct cpufreq_frequency_table *table)
56 {
57 struct cpufreq_frequency_table *pos;
58 unsigned int freq, next_larger = ~0;
59 bool found = false;
60
61 pr_debug("request for verification of policy (%u - %u kHz) for cpu %u\n",
62 policy->min, policy->max, policy->cpu);
63
64 cpufreq_verify_within_cpu_limits(policy);
65
66 cpufreq_for_each_valid_entry(pos, table) {
67 freq = pos->frequency;
68
69 if ((freq >= policy->min) && (freq <= policy->max)) {
70 found = true;
71 break;
72 }
73
74 if ((next_larger > freq) && (freq > policy->max))
75 next_larger = freq;
76 }
77
78 if (!found) {
79 policy->max = next_larger;
80 cpufreq_verify_within_cpu_limits(policy);
81 }
82
83 pr_debug("verification lead to (%u - %u kHz) for cpu %u\n",
84 policy->min, policy->max, policy->cpu);
85
86 return 0;
87 }
88 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_verify);
89
90 /*
91 * Generic routine to verify policy & frequency table, requires driver to set
92 * policy->freq_table prior to it.
93 */
cpufreq_generic_frequency_table_verify(struct cpufreq_policy * policy)94 int cpufreq_generic_frequency_table_verify(struct cpufreq_policy *policy)
95 {
96 struct cpufreq_frequency_table *table =
97 cpufreq_frequency_get_table(policy->cpu);
98 if (!table)
99 return -ENODEV;
100
101 return cpufreq_frequency_table_verify(policy, table);
102 }
103 EXPORT_SYMBOL_GPL(cpufreq_generic_frequency_table_verify);
104
cpufreq_frequency_table_target(struct cpufreq_policy * policy,struct cpufreq_frequency_table * table,unsigned int target_freq,unsigned int relation,unsigned int * index)105 int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
106 struct cpufreq_frequency_table *table,
107 unsigned int target_freq,
108 unsigned int relation,
109 unsigned int *index)
110 {
111 struct cpufreq_frequency_table optimal = {
112 .driver_data = ~0,
113 .frequency = 0,
114 };
115 struct cpufreq_frequency_table suboptimal = {
116 .driver_data = ~0,
117 .frequency = 0,
118 };
119 struct cpufreq_frequency_table *pos;
120 unsigned int freq, diff, i = 0;
121
122 pr_debug("request for target %u kHz (relation: %u) for cpu %u\n",
123 target_freq, relation, policy->cpu);
124
125 switch (relation) {
126 case CPUFREQ_RELATION_H:
127 suboptimal.frequency = ~0;
128 break;
129 case CPUFREQ_RELATION_L:
130 case CPUFREQ_RELATION_C:
131 optimal.frequency = ~0;
132 break;
133 }
134
135 cpufreq_for_each_valid_entry(pos, table) {
136 freq = pos->frequency;
137
138 i = pos - table;
139 if ((freq < policy->min) || (freq > policy->max))
140 continue;
141 if (freq == target_freq) {
142 optimal.driver_data = i;
143 break;
144 }
145 switch (relation) {
146 case CPUFREQ_RELATION_H:
147 if (freq < target_freq) {
148 if (freq >= optimal.frequency) {
149 optimal.frequency = freq;
150 optimal.driver_data = i;
151 }
152 } else {
153 if (freq <= suboptimal.frequency) {
154 suboptimal.frequency = freq;
155 suboptimal.driver_data = i;
156 }
157 }
158 break;
159 case CPUFREQ_RELATION_L:
160 if (freq > target_freq) {
161 if (freq <= optimal.frequency) {
162 optimal.frequency = freq;
163 optimal.driver_data = i;
164 }
165 } else {
166 if (freq >= suboptimal.frequency) {
167 suboptimal.frequency = freq;
168 suboptimal.driver_data = i;
169 }
170 }
171 break;
172 case CPUFREQ_RELATION_C:
173 diff = abs(freq - target_freq);
174 if (diff < optimal.frequency ||
175 (diff == optimal.frequency &&
176 freq > table[optimal.driver_data].frequency)) {
177 optimal.frequency = diff;
178 optimal.driver_data = i;
179 }
180 break;
181 }
182 }
183 if (optimal.driver_data > i) {
184 if (suboptimal.driver_data > i)
185 return -EINVAL;
186 *index = suboptimal.driver_data;
187 } else
188 *index = optimal.driver_data;
189
190 pr_debug("target index is %u, freq is:%u kHz\n", *index,
191 table[*index].frequency);
192
193 return 0;
194 }
195 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_target);
196
cpufreq_frequency_table_get_index(struct cpufreq_policy * policy,unsigned int freq)197 int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy,
198 unsigned int freq)
199 {
200 struct cpufreq_frequency_table *pos, *table;
201
202 table = cpufreq_frequency_get_table(policy->cpu);
203 if (unlikely(!table)) {
204 pr_debug("%s: Unable to find frequency table\n", __func__);
205 return -ENOENT;
206 }
207
208 cpufreq_for_each_valid_entry(pos, table)
209 if (pos->frequency == freq)
210 return pos - table;
211
212 return -EINVAL;
213 }
214 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_get_index);
215
216 /**
217 * show_available_freqs - show available frequencies for the specified CPU
218 */
show_available_freqs(struct cpufreq_policy * policy,char * buf,bool show_boost)219 static ssize_t show_available_freqs(struct cpufreq_policy *policy, char *buf,
220 bool show_boost)
221 {
222 ssize_t count = 0;
223 struct cpufreq_frequency_table *pos, *table = policy->freq_table;
224
225 if (!table)
226 return -ENODEV;
227
228 cpufreq_for_each_valid_entry(pos, table) {
229 /*
230 * show_boost = true and driver_data = BOOST freq
231 * display BOOST freqs
232 *
233 * show_boost = false and driver_data = BOOST freq
234 * show_boost = true and driver_data != BOOST freq
235 * continue - do not display anything
236 *
237 * show_boost = false and driver_data != BOOST freq
238 * display NON BOOST freqs
239 */
240 if (show_boost ^ (pos->flags & CPUFREQ_BOOST_FREQ))
241 continue;
242
243 count += sprintf(&buf[count], "%d ", pos->frequency);
244 }
245 count += sprintf(&buf[count], "\n");
246
247 return count;
248
249 }
250
251 #define cpufreq_attr_available_freq(_name) \
252 struct freq_attr cpufreq_freq_attr_##_name##_freqs = \
253 __ATTR_RO(_name##_frequencies)
254
255 /**
256 * show_scaling_available_frequencies - show available normal frequencies for
257 * the specified CPU
258 */
scaling_available_frequencies_show(struct cpufreq_policy * policy,char * buf)259 static ssize_t scaling_available_frequencies_show(struct cpufreq_policy *policy,
260 char *buf)
261 {
262 return show_available_freqs(policy, buf, false);
263 }
264 cpufreq_attr_available_freq(scaling_available);
265 EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_available_freqs);
266
267 /**
268 * show_available_boost_freqs - show available boost frequencies for
269 * the specified CPU
270 */
scaling_boost_frequencies_show(struct cpufreq_policy * policy,char * buf)271 static ssize_t scaling_boost_frequencies_show(struct cpufreq_policy *policy,
272 char *buf)
273 {
274 return show_available_freqs(policy, buf, true);
275 }
276 cpufreq_attr_available_freq(scaling_boost);
277 EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_boost_freqs);
278
279 struct freq_attr *cpufreq_generic_attr[] = {
280 &cpufreq_freq_attr_scaling_available_freqs,
281 #ifdef CONFIG_CPU_FREQ_BOOST_SW
282 &cpufreq_freq_attr_scaling_boost_freqs,
283 #endif
284 NULL,
285 };
286 EXPORT_SYMBOL_GPL(cpufreq_generic_attr);
287
cpufreq_table_validate_and_show(struct cpufreq_policy * policy,struct cpufreq_frequency_table * table)288 int cpufreq_table_validate_and_show(struct cpufreq_policy *policy,
289 struct cpufreq_frequency_table *table)
290 {
291 int ret = cpufreq_frequency_table_cpuinfo(policy, table);
292
293 if (!ret)
294 policy->freq_table = table;
295
296 return ret;
297 }
298 EXPORT_SYMBOL_GPL(cpufreq_table_validate_and_show);
299
300 struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu);
301
cpufreq_frequency_get_table(unsigned int cpu)302 struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu)
303 {
304 struct cpufreq_policy *policy = cpufreq_cpu_get_raw(cpu);
305 return policy ? policy->freq_table : NULL;
306 }
307 EXPORT_SYMBOL_GPL(cpufreq_frequency_get_table);
308
309 MODULE_AUTHOR("Dominik Brodowski <linux@brodo.de>");
310 MODULE_DESCRIPTION("CPUfreq frequency table helpers");
311 MODULE_LICENSE("GPL");
312