blob: 551f4ccf87fd9eba99657b713250dd23c5723ad3 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/drivers/cpufreq/freq_table.c
3 *
4 * Copyright (C) 2002 - 2003 Dominik Brodowski
5 */
6
7#include <linux/kernel.h>
8#include <linux/module.h>
9#include <linux/init.h>
10#include <linux/cpufreq.h>
11
12#define dprintk(msg...) cpufreq_debug_printk(CPUFREQ_DEBUG_CORE, "freq-table", msg)
13
14/*********************************************************************
15 * FREQUENCY TABLE HELPERS *
16 *********************************************************************/
17
18int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
19 struct cpufreq_frequency_table *table)
20{
21 unsigned int min_freq = ~0;
22 unsigned int max_freq = 0;
Dave Jones355eb312006-05-30 17:58:41 -040023 unsigned int i;
Linus Torvalds1da177e2005-04-16 15:20:36 -070024
25 for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
26 unsigned int freq = table[i].frequency;
27 if (freq == CPUFREQ_ENTRY_INVALID) {
28 dprintk("table entry %u is invalid, skipping\n", i);
29
30 continue;
31 }
32 dprintk("table entry %u: %u kHz, %u index\n", i, freq, table[i].index);
33 if (freq < min_freq)
34 min_freq = freq;
35 if (freq > max_freq)
36 max_freq = freq;
37 }
38
39 policy->min = policy->cpuinfo.min_freq = min_freq;
40 policy->max = policy->cpuinfo.max_freq = max_freq;
41
42 if (policy->min == ~0)
43 return -EINVAL;
44 else
45 return 0;
46}
47EXPORT_SYMBOL_GPL(cpufreq_frequency_table_cpuinfo);
48
49
50int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
51 struct cpufreq_frequency_table *table)
52{
53 unsigned int next_larger = ~0;
Dave Jones55579762006-05-30 17:59:48 -040054 unsigned int i;
Linus Torvalds1da177e2005-04-16 15:20:36 -070055 unsigned int count = 0;
56
57 dprintk("request for verification of policy (%u - %u kHz) for cpu %u\n", policy->min, policy->max, policy->cpu);
58
59 if (!cpu_online(policy->cpu))
60 return -EINVAL;
61
Dave Jones32ee8c32006-02-28 00:43:23 -050062 cpufreq_verify_within_limits(policy,
63 policy->cpuinfo.min_freq, policy->cpuinfo.max_freq);
Linus Torvalds1da177e2005-04-16 15:20:36 -070064
65 for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
66 unsigned int freq = table[i].frequency;
67 if (freq == CPUFREQ_ENTRY_INVALID)
68 continue;
69 if ((freq >= policy->min) && (freq <= policy->max))
70 count++;
71 else if ((next_larger > freq) && (freq > policy->max))
72 next_larger = freq;
73 }
74
75 if (!count)
76 policy->max = next_larger;
77
Dave Jones32ee8c32006-02-28 00:43:23 -050078 cpufreq_verify_within_limits(policy,
79 policy->cpuinfo.min_freq, policy->cpuinfo.max_freq);
Linus Torvalds1da177e2005-04-16 15:20:36 -070080
81 dprintk("verification lead to (%u - %u kHz) for cpu %u\n", policy->min, policy->max, policy->cpu);
82
83 return 0;
84}
85EXPORT_SYMBOL_GPL(cpufreq_frequency_table_verify);
86
87
88int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
89 struct cpufreq_frequency_table *table,
90 unsigned int target_freq,
91 unsigned int relation,
92 unsigned int *index)
93{
Dave Jones484944a2006-05-30 18:09:31 -040094 struct cpufreq_frequency_table optimal = {
95 .index = ~0,
96 .frequency = 0,
97 };
98 struct cpufreq_frequency_table suboptimal = {
99 .index = ~0,
100 .frequency = 0,
101 };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102 unsigned int i;
103
104 dprintk("request for target %u kHz (relation: %u) for cpu %u\n", target_freq, relation, policy->cpu);
105
106 switch (relation) {
107 case CPUFREQ_RELATION_H:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108 suboptimal.frequency = ~0;
109 break;
110 case CPUFREQ_RELATION_L:
111 optimal.frequency = ~0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112 break;
113 }
114
115 if (!cpu_online(policy->cpu))
116 return -EINVAL;
117
118 for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
119 unsigned int freq = table[i].frequency;
120 if (freq == CPUFREQ_ENTRY_INVALID)
121 continue;
122 if ((freq < policy->min) || (freq > policy->max))
123 continue;
124 switch(relation) {
125 case CPUFREQ_RELATION_H:
126 if (freq <= target_freq) {
127 if (freq >= optimal.frequency) {
128 optimal.frequency = freq;
129 optimal.index = i;
130 }
131 } else {
132 if (freq <= suboptimal.frequency) {
133 suboptimal.frequency = freq;
134 suboptimal.index = i;
135 }
136 }
137 break;
138 case CPUFREQ_RELATION_L:
139 if (freq >= target_freq) {
140 if (freq <= optimal.frequency) {
141 optimal.frequency = freq;
142 optimal.index = i;
143 }
144 } else {
145 if (freq >= suboptimal.frequency) {
146 suboptimal.frequency = freq;
147 suboptimal.index = i;
148 }
149 }
150 break;
151 }
152 }
153 if (optimal.index > i) {
154 if (suboptimal.index > i)
155 return -EINVAL;
156 *index = suboptimal.index;
157 } else
158 *index = optimal.index;
159
160 dprintk("target is %u (%u kHz, %u)\n", *index, table[*index].frequency,
161 table[*index].index);
162
163 return 0;
164}
165EXPORT_SYMBOL_GPL(cpufreq_frequency_table_target);
166
167static struct cpufreq_frequency_table *show_table[NR_CPUS];
168/**
169 * show_scaling_governor - show the current policy for the specified CPU
170 */
171static ssize_t show_available_freqs (struct cpufreq_policy *policy, char *buf)
172{
173 unsigned int i = 0;
174 unsigned int cpu = policy->cpu;
175 ssize_t count = 0;
176 struct cpufreq_frequency_table *table;
177
178 if (!show_table[cpu])
179 return -ENODEV;
180
181 table = show_table[cpu];
182
183 for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
184 if (table[i].frequency == CPUFREQ_ENTRY_INVALID)
185 continue;
186 count += sprintf(&buf[count], "%d ", table[i].frequency);
187 }
188 count += sprintf(&buf[count], "\n");
189
190 return count;
191
192}
193
194struct freq_attr cpufreq_freq_attr_scaling_available_freqs = {
195 .attr = { .name = "scaling_available_frequencies", .mode = 0444, .owner=THIS_MODULE },
196 .show = show_available_freqs,
197};
198EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_available_freqs);
199
200/*
201 * if you use these, you must assure that the frequency table is valid
202 * all the time between get_attr and put_attr!
203 */
Dave Jones32ee8c32006-02-28 00:43:23 -0500204void cpufreq_frequency_table_get_attr(struct cpufreq_frequency_table *table,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700205 unsigned int cpu)
206{
207 dprintk("setting show_table for cpu %u to %p\n", cpu, table);
208 show_table[cpu] = table;
209}
210EXPORT_SYMBOL_GPL(cpufreq_frequency_table_get_attr);
211
212void cpufreq_frequency_table_put_attr(unsigned int cpu)
213{
214 dprintk("clearing show_table for cpu %u\n", cpu);
215 show_table[cpu] = NULL;
216}
217EXPORT_SYMBOL_GPL(cpufreq_frequency_table_put_attr);
218
219struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu)
220{
221 return show_table[cpu];
222}
223EXPORT_SYMBOL_GPL(cpufreq_frequency_get_table);
224
225MODULE_AUTHOR ("Dominik Brodowski <linux@brodo.de>");
226MODULE_DESCRIPTION ("CPUfreq frequency table helpers");
227MODULE_LICENSE ("GPL");