2 * linux/drivers/cpufreq/freq_table.c
4 * Copyright (C) 2002 - 2003 Dominik Brodowski
7 #include <linux/kernel.h>
8 #include <linux/module.h>
9 #include <linux/init.h>
10 #include <linux/cpufreq.h>
12 /*********************************************************************
13 * FREQUENCY TABLE HELPERS *
14 *********************************************************************/
16 int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
17 struct cpufreq_frequency_table *table)
19 unsigned int min_freq = ~0;
20 unsigned int max_freq = 0;
23 for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
24 unsigned int freq = table[i].frequency;
25 if (freq == CPUFREQ_ENTRY_INVALID)
33 policy->min = policy->cpuinfo.min_freq = min_freq;
34 policy->max = policy->cpuinfo.max_freq = max_freq;
36 if (policy->min == ~0)
41 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_cpuinfo);
44 int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
45 struct cpufreq_frequency_table *table)
47 unsigned int next_larger = ~0;
49 unsigned int count = 0;
51 if (!cpu_online(policy->cpu))
54 cpufreq_verify_within_limits(policy,
55 policy->cpuinfo.min_freq,
56 policy->cpuinfo.max_freq);
58 for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
59 unsigned int freq = table[i].frequency;
60 if (freq == CPUFREQ_ENTRY_INVALID)
62 if ((freq >= policy->min) && (freq <= policy->max))
64 else if ((next_larger > freq) && (freq > policy->max))
69 policy->max = next_larger;
71 cpufreq_verify_within_limits(policy,
72 policy->cpuinfo.min_freq,
73 policy->cpuinfo.max_freq);
77 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_verify);
80 int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
81 struct cpufreq_frequency_table *table,
82 unsigned int target_freq,
83 unsigned int relation,
86 struct cpufreq_frequency_table optimal = { .index = ~0, };
87 struct cpufreq_frequency_table suboptimal = { .index = ~0, };
91 case CPUFREQ_RELATION_H:
92 optimal.frequency = 0;
93 suboptimal.frequency = ~0;
95 case CPUFREQ_RELATION_L:
96 optimal.frequency = ~0;
97 suboptimal.frequency = 0;
101 if (!cpu_online(policy->cpu))
104 for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
105 unsigned int freq = table[i].frequency;
106 if (freq == CPUFREQ_ENTRY_INVALID)
108 if ((freq < policy->min) || (freq > policy->max))
111 case CPUFREQ_RELATION_H:
112 if (freq <= target_freq) {
113 if (freq >= optimal.frequency) {
114 optimal.frequency = freq;
118 if (freq <= suboptimal.frequency) {
119 suboptimal.frequency = freq;
120 suboptimal.index = i;
124 case CPUFREQ_RELATION_L:
125 if (freq >= target_freq) {
126 if (freq <= optimal.frequency) {
127 optimal.frequency = freq;
131 if (freq >= suboptimal.frequency) {
132 suboptimal.frequency = freq;
133 suboptimal.index = i;
139 if (optimal.index > i) {
140 if (suboptimal.index > i)
142 *index = suboptimal.index;
144 *index = optimal.index;
148 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_target);
150 static struct cpufreq_frequency_table *show_table[NR_CPUS];
152 * show_scaling_governor - show the current policy for the specified CPU
154 static ssize_t show_available_freqs (struct cpufreq_policy *policy, char *buf)
157 unsigned int cpu = policy->cpu;
159 struct cpufreq_frequency_table *table;
161 if (!show_table[cpu])
164 table = show_table[cpu];
166 for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
167 if (table[i].frequency == CPUFREQ_ENTRY_INVALID)
169 count += sprintf(&buf[count], "%d ", table[i].frequency);
171 count += sprintf(&buf[count], "\n");
177 struct freq_attr cpufreq_freq_attr_scaling_available_freqs = {
178 .attr = { .name = "scaling_available_frequencies", .mode = 0444 },
179 .show = show_available_freqs,
181 EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_available_freqs);
184 * if you use these, you must assure that the frequency table is valid
185 * all the time between get_attr and put_attr!
187 void cpufreq_frequency_table_get_attr(struct cpufreq_frequency_table *table,
190 show_table[cpu] = table;
192 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_get_attr);
194 void cpufreq_frequency_table_put_attr(unsigned int cpu)
196 show_table[cpu] = NULL;
198 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_put_attr);
201 MODULE_AUTHOR ("Dominik Brodowski <linux@brodo.de>");
202 MODULE_DESCRIPTION ("CPUfreq frequency table helpers");
203 MODULE_LICENSE ("GPL");