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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...) \
13 cpufreq_debug_printk(CPUFREQ_DEBUG_CORE, "freq-table", msg)
14
15
16
17
18
19int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
20 struct cpufreq_frequency_table *table)
21{
22 unsigned int min_freq = ~0;
23 unsigned int max_freq = 0;
24 unsigned int i;
25
26 for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
27 unsigned int freq = table[i].frequency;
28 if (freq == CPUFREQ_ENTRY_INVALID) {
29 dprintk("table entry %u is invalid, skipping\n", i);
30
31 continue;
32 }
33 dprintk("table entry %u: %u kHz, %u index\n",
34 i, freq, table[i].index);
35 if (freq < min_freq)
36 min_freq = freq;
37 if (freq > max_freq)
38 max_freq = freq;
39 }
40
41 policy->min = policy->cpuinfo.min_freq = min_freq;
42 policy->max = policy->cpuinfo.max_freq = max_freq;
43
44 if (policy->min == ~0)
45 return -EINVAL;
46 else
47 return 0;
48}
49EXPORT_SYMBOL_GPL(cpufreq_frequency_table_cpuinfo);
50
51
52int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
53 struct cpufreq_frequency_table *table)
54{
55 unsigned int next_larger = ~0;
56 unsigned int i;
57 unsigned int count = 0;
58
59 dprintk("request for verification of policy (%u - %u kHz) for cpu %u\n",
60 policy->min, policy->max, policy->cpu);
61
62 if (!cpu_online(policy->cpu))
63 return -EINVAL;
64
65 cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
66 policy->cpuinfo.max_freq);
67
68 for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
69 unsigned int freq = table[i].frequency;
70 if (freq == CPUFREQ_ENTRY_INVALID)
71 continue;
72 if ((freq >= policy->min) && (freq <= policy->max))
73 count++;
74 else if ((next_larger > freq) && (freq > policy->max))
75 next_larger = freq;
76 }
77
78 if (!count)
79 policy->max = next_larger;
80
81 cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
82 policy->cpuinfo.max_freq);
83
84 dprintk("verification lead to (%u - %u kHz) for cpu %u\n",
85 policy->min, policy->max, policy->cpu);
86
87 return 0;
88}
89EXPORT_SYMBOL_GPL(cpufreq_frequency_table_verify);
90
91
92int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
93 struct cpufreq_frequency_table *table,
94 unsigned int target_freq,
95 unsigned int relation,
96 unsigned int *index)
97{
98 struct cpufreq_frequency_table optimal = {
99 .index = ~0,
100 .frequency = 0,
101 };
102 struct cpufreq_frequency_table suboptimal = {
103 .index = ~0,
104 .frequency = 0,
105 };
106 unsigned int i;
107
108 dprintk("request for target %u kHz (relation: %u) for cpu %u\n",
109 target_freq, relation, policy->cpu);
110
111 switch (relation) {
112 case CPUFREQ_RELATION_H:
113 suboptimal.frequency = ~0;
114 break;
115 case CPUFREQ_RELATION_L:
116 optimal.frequency = ~0;
117 break;
118 }
119
120 if (!cpu_online(policy->cpu))
121 return -EINVAL;
122
123 for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
124 unsigned int freq = table[i].frequency;
125 if (freq == CPUFREQ_ENTRY_INVALID)
126 continue;
127 if ((freq < policy->min) || (freq > policy->max))
128 continue;
129 switch(relation) {
130 case CPUFREQ_RELATION_H:
131 if (freq <= target_freq) {
132 if (freq >= optimal.frequency) {
133 optimal.frequency = freq;
134 optimal.index = i;
135 }
136 } else {
137 if (freq <= suboptimal.frequency) {
138 suboptimal.frequency = freq;
139 suboptimal.index = i;
140 }
141 }
142 break;
143 case CPUFREQ_RELATION_L:
144 if (freq >= target_freq) {
145 if (freq <= optimal.frequency) {
146 optimal.frequency = freq;
147 optimal.index = i;
148 }
149 } else {
150 if (freq >= suboptimal.frequency) {
151 suboptimal.frequency = freq;
152 suboptimal.index = i;
153 }
154 }
155 break;
156 }
157 }
158 if (optimal.index > i) {
159 if (suboptimal.index > i)
160 return -EINVAL;
161 *index = suboptimal.index;
162 } else
163 *index = optimal.index;
164
165 dprintk("target is %u (%u kHz, %u)\n", *index, table[*index].frequency,
166 table[*index].index);
167
168 return 0;
169}
170EXPORT_SYMBOL_GPL(cpufreq_frequency_table_target);
171
172static struct cpufreq_frequency_table *show_table[NR_CPUS];
173
174
175
176static ssize_t show_available_freqs (struct cpufreq_policy *policy, char *buf)
177{
178 unsigned int i = 0;
179 unsigned int cpu = policy->cpu;
180 ssize_t count = 0;
181 struct cpufreq_frequency_table *table;
182
183 if (!show_table[cpu])
184 return -ENODEV;
185
186 table = show_table[cpu];
187
188 for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
189 if (table[i].frequency == CPUFREQ_ENTRY_INVALID)
190 continue;
191 count += sprintf(&buf[count], "%d ", table[i].frequency);
192 }
193 count += sprintf(&buf[count], "\n");
194
195 return count;
196
197}
198
199struct freq_attr cpufreq_freq_attr_scaling_available_freqs = {
200 .attr = { .name = "scaling_available_frequencies",
201 .mode = 0444,
202 },
203 .show = show_available_freqs,
204};
205EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_available_freqs);
206
207
208
209
210
211void cpufreq_frequency_table_get_attr(struct cpufreq_frequency_table *table,
212 unsigned int cpu)
213{
214 dprintk("setting show_table for cpu %u to %p\n", cpu, table);
215 show_table[cpu] = table;
216}
217EXPORT_SYMBOL_GPL(cpufreq_frequency_table_get_attr);
218
219void cpufreq_frequency_table_put_attr(unsigned int cpu)
220{
221 dprintk("clearing show_table for cpu %u\n", cpu);
222 show_table[cpu] = NULL;
223}
224EXPORT_SYMBOL_GPL(cpufreq_frequency_table_put_attr);
225
226struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu)
227{
228 return show_table[cpu];
229}
230EXPORT_SYMBOL_GPL(cpufreq_frequency_get_table);
231
232MODULE_AUTHOR ("Dominik Brodowski <linux@brodo.de>");
233MODULE_DESCRIPTION ("CPUfreq frequency table helpers");
234MODULE_LICENSE ("GPL");
235
