2 * linux/drivers/cpufreq/freq_table.c
4 * Copyright (C) 2002 - 2003 Dominik Brodowski
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.
12 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/init.h>
17 #include <linux/cpufreq.h>
19 /*********************************************************************
20 * FREQUENCY TABLE HELPERS *
21 *********************************************************************/
23 int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
24 struct cpufreq_frequency_table *table)
26 unsigned int min_freq = ~0;
27 unsigned int max_freq = 0;
30 for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
31 unsigned int freq = table[i].frequency;
32 if (freq == CPUFREQ_ENTRY_INVALID) {
33 pr_debug("table entry %u is invalid, skipping\n", i);
37 pr_debug("table entry %u: %u kHz, %u index\n",
38 i, freq, table[i].index);
45 policy->min = policy->cpuinfo.min_freq = min_freq;
46 policy->max = policy->cpuinfo.max_freq = max_freq;
48 if (policy->min == ~0)
53 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_cpuinfo);
56 int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
57 struct cpufreq_frequency_table *table)
59 unsigned int next_larger = ~0;
61 unsigned int count = 0;
63 pr_debug("request for verification of policy (%u - %u kHz) for cpu %u\n",
64 policy->min, policy->max, policy->cpu);
66 if (!cpu_online(policy->cpu))
69 cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
70 policy->cpuinfo.max_freq);
72 for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
73 unsigned int freq = table[i].frequency;
74 if (freq == CPUFREQ_ENTRY_INVALID)
76 if ((freq >= policy->min) && (freq <= policy->max))
78 else if ((next_larger > freq) && (freq > policy->max))
83 policy->max = next_larger;
85 cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
86 policy->cpuinfo.max_freq);
88 pr_debug("verification lead to (%u - %u kHz) for cpu %u\n",
89 policy->min, policy->max, policy->cpu);
93 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_verify);
96 int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
97 struct cpufreq_frequency_table *table,
98 unsigned int target_freq,
99 unsigned int relation,
102 struct cpufreq_frequency_table optimal = {
106 struct cpufreq_frequency_table suboptimal = {
112 pr_debug("request for target %u kHz (relation: %u) for cpu %u\n",
113 target_freq, relation, policy->cpu);
116 case CPUFREQ_RELATION_H:
117 suboptimal.frequency = ~0;
119 case CPUFREQ_RELATION_L:
120 optimal.frequency = ~0;
124 if (!cpu_online(policy->cpu))
127 for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
128 unsigned int freq = table[i].frequency;
129 if (freq == CPUFREQ_ENTRY_INVALID)
131 if ((freq < policy->min) || (freq > policy->max))
134 case CPUFREQ_RELATION_H:
135 if (freq <= target_freq) {
136 if (freq >= optimal.frequency) {
137 optimal.frequency = freq;
141 if (freq <= suboptimal.frequency) {
142 suboptimal.frequency = freq;
143 suboptimal.index = i;
147 case CPUFREQ_RELATION_L:
148 if (freq >= target_freq) {
149 if (freq <= optimal.frequency) {
150 optimal.frequency = freq;
154 if (freq >= suboptimal.frequency) {
155 suboptimal.frequency = freq;
156 suboptimal.index = i;
162 if (optimal.index > i) {
163 if (suboptimal.index > i)
165 *index = suboptimal.index;
167 *index = optimal.index;
169 pr_debug("target is %u (%u kHz, %u)\n", *index, table[*index].frequency,
170 table[*index].index);
174 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_target);
176 static DEFINE_PER_CPU(struct cpufreq_frequency_table *, cpufreq_show_table);
178 * show_available_freqs - show available frequencies for the specified CPU
180 static ssize_t show_available_freqs(struct cpufreq_policy *policy, char *buf)
183 unsigned int cpu = policy->cpu;
185 struct cpufreq_frequency_table *table;
187 if (!per_cpu(cpufreq_show_table, cpu))
190 table = per_cpu(cpufreq_show_table, cpu);
192 for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
193 if (table[i].frequency == CPUFREQ_ENTRY_INVALID)
195 count += sprintf(&buf[count], "%d ", table[i].frequency);
197 count += sprintf(&buf[count], "\n");
203 struct freq_attr cpufreq_freq_attr_scaling_available_freqs = {
204 .attr = { .name = "scaling_available_frequencies",
207 .show = show_available_freqs,
209 EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_available_freqs);
212 * if you use these, you must assure that the frequency table is valid
213 * all the time between get_attr and put_attr!
215 void cpufreq_frequency_table_get_attr(struct cpufreq_frequency_table *table,
218 pr_debug("setting show_table for cpu %u to %p\n", cpu, table);
219 per_cpu(cpufreq_show_table, cpu) = table;
221 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_get_attr);
223 void cpufreq_frequency_table_put_attr(unsigned int cpu)
225 pr_debug("clearing show_table for cpu %u\n", cpu);
226 per_cpu(cpufreq_show_table, cpu) = NULL;
228 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_put_attr);
230 struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu)
232 return per_cpu(cpufreq_show_table, cpu);
234 EXPORT_SYMBOL_GPL(cpufreq_frequency_get_table);
236 MODULE_AUTHOR("Dominik Brodowski <linux@brodo.de>");
237 MODULE_DESCRIPTION("CPUfreq frequency table helpers");
238 MODULE_LICENSE("GPL");