summaryrefslogtreecommitdiff
path: root/drivers/cpufreq/freq_table.c
blob: 8e54f97899ba6feb7225275b7ddf2473ff8dc35b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
/*
 * linux/drivers/cpufreq/freq_table.c
 *
 * Copyright (C) 2002 - 2003 Dominik Brodowski
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/cpufreq.h>
#include <linux/module.h>

/*********************************************************************
 *                     FREQUENCY TABLE HELPERS                       *
 *********************************************************************/

int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
				    struct cpufreq_frequency_table *table)
{
	unsigned int min_freq = ~0;
	unsigned int max_freq = 0;
	unsigned int i;

	for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
		unsigned int freq = table[i].frequency;
		if (freq == CPUFREQ_ENTRY_INVALID) {
			pr_debug("table entry %u is invalid, skipping\n", i);

			continue;
		}
		if (!cpufreq_boost_enabled()
		    && table[i].driver_data == CPUFREQ_BOOST_FREQ)
			continue;

		pr_debug("table entry %u: %u kHz, %u driver_data\n",
					i, freq, table[i].driver_data);
		if (freq < min_freq)
			min_freq = freq;
		if (freq > max_freq)
			max_freq = freq;
	}

	policy->min = policy->cpuinfo.min_freq = min_freq;
	policy->max = policy->cpuinfo.max_freq = max_freq;

	if (policy->min == ~0)
		return -EINVAL;
	else
		return 0;
}
EXPORT_SYMBOL_GPL(cpufreq_frequency_table_cpuinfo);


int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
				   struct cpufreq_frequency_table *table)
{
	unsigned int next_larger = ~0, freq, i = 0;
	bool found = false;

	pr_debug("request for verification of policy (%u - %u kHz) for cpu %u\n",
					policy->min, policy->max, policy->cpu);

	cpufreq_verify_within_cpu_limits(policy);

	for (; freq = table[i].frequency, freq != CPUFREQ_TABLE_END; i++) {
		if (freq == CPUFREQ_ENTRY_INVALID)
			continue;
		if ((freq >= policy->min) && (freq <= policy->max)) {
			found = true;
			break;
		}

		if ((next_larger > freq) && (freq > policy->max))
			next_larger = freq;
	}

	if (!found) {
		policy->max = next_larger;
		cpufreq_verify_within_cpu_limits(policy);
	}

	pr_debug("verification lead to (%u - %u kHz) for cpu %u\n",
				policy->min, policy->max, policy->cpu);

	return 0;
}
EXPORT_SYMBOL_GPL(cpufreq_frequency_table_verify);

/*
 * Generic routine to verify policy & frequency table, requires driver to call
 * cpufreq_frequency_table_get_attr() prior to it.
 */
int cpufreq_generic_frequency_table_verify(struct cpufreq_policy *policy)
{
	struct cpufreq_frequency_table *table =
		cpufreq_frequency_get_table(policy->cpu);
	if (!table)
		return -ENODEV;

	return cpufreq_frequency_table_verify(policy, table);
}
EXPORT_SYMBOL_GPL(cpufreq_generic_frequency_table_verify);

int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
				   struct cpufreq_frequency_table *table,
				   unsigned int target_freq,
				   unsigned int relation,
				   unsigned int *index)
{
	struct cpufreq_frequency_table optimal = {
		.driver_data = ~0,
		.frequency = 0,
	};
	struct cpufreq_frequency_table suboptimal = {
		.driver_data = ~0,
		.frequency = 0,
	};
	unsigned int i;

	pr_debug("request for target %u kHz (relation: %u) for cpu %u\n",
					target_freq, relation, policy->cpu);

	switch (relation) {
	case CPUFREQ_RELATION_H:
		suboptimal.frequency = ~0;
		break;
	case CPUFREQ_RELATION_L:
		optimal.frequency = ~0;
		break;
	}

	for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
		unsigned int freq = table[i].frequency;
		if (freq == CPUFREQ_ENTRY_INVALID)
			continue;
		if ((freq < policy->min) || (freq > policy->max))
			continue;
		switch (relation) {
		case CPUFREQ_RELATION_H:
			if (freq <= target_freq) {
				if (freq >= optimal.frequency) {
					optimal.frequency = freq;
					optimal.driver_data = i;
				}
			} else {
				if (freq <= suboptimal.frequency) {
					suboptimal.frequency = freq;
					suboptimal.driver_data = i;
				}
			}
			break;
		case CPUFREQ_RELATION_L:
			if (freq >= target_freq) {
				if (freq <= optimal.frequency) {
					optimal.frequency = freq;
					optimal.driver_data = i;
				}
			} else {
				if (freq >= suboptimal.frequency) {
					suboptimal.frequency = freq;
					suboptimal.driver_data = i;
				}
			}
			break;
		}
	}
	if (optimal.driver_data > i) {
		if (suboptimal.driver_data > i)
			return -EINVAL;
		*index = suboptimal.driver_data;
	} else
		*index = optimal.driver_data;

	pr_debug("target is %u (%u kHz, %u)\n", *index, table[*index].frequency,
		table[*index].driver_data);

	return 0;
}
EXPORT_SYMBOL_GPL(cpufreq_frequency_table_target);

int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy,
		unsigned int freq)
{
	struct cpufreq_frequency_table *table;
	int i;

	table = cpufreq_frequency_get_table(policy->cpu);
	if (unlikely(!table)) {
		pr_debug("%s: Unable to find frequency table\n", __func__);
		return -ENOENT;
	}

	for (i = 0; table[i].frequency != CPUFREQ_TABLE_END; i++) {
		if (table[i].frequency == freq)
			return i;
	}

	return -EINVAL;
}
EXPORT_SYMBOL_GPL(cpufreq_frequency_table_get_index);

static DEFINE_PER_CPU(struct cpufreq_frequency_table *, cpufreq_show_table);

/**
 * show_available_freqs - show available frequencies for the specified CPU
 */
static ssize_t show_available_freqs(struct cpufreq_policy *policy, char *buf,
				    bool show_boost)
{
	unsigned int i = 0;
	unsigned int cpu = policy->cpu;
	ssize_t count = 0;
	struct cpufreq_frequency_table *table;

	if (!per_cpu(cpufreq_show_table, cpu))
		return -ENODEV;

	table = per_cpu(cpufreq_show_table, cpu);

	for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
		if (table[i].frequency == CPUFREQ_ENTRY_INVALID)
			continue;
		/*
		 * show_boost = true and driver_data = BOOST freq
		 * display BOOST freqs
		 *
		 * show_boost = false and driver_data = BOOST freq
		 * show_boost = true and driver_data != BOOST freq
		 * continue - do not display anything
		 *
		 * show_boost = false and driver_data != BOOST freq
		 * display NON BOOST freqs
		 */
		if (show_boost ^ (table[i].driver_data == CPUFREQ_BOOST_FREQ))
			continue;

		count += sprintf(&buf[count], "%d ", table[i].frequency);
	}
	count += sprintf(&buf[count], "\n");

	return count;

}

#define cpufreq_attr_available_freq(_name)	  \
struct freq_attr cpufreq_freq_attr_##_name##_freqs =     \
__ATTR_RO(_name##_frequencies)

/**
 * show_scaling_available_frequencies - show available normal frequencies for
 * the specified CPU
 */
static ssize_t scaling_available_frequencies_show(struct cpufreq_policy *policy,
						  char *buf)
{
	return show_available_freqs(policy, buf, false);
}
cpufreq_attr_available_freq(scaling_available);
EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_available_freqs);

/**
 * show_available_boost_freqs - show available boost frequencies for
 * the specified CPU
 */
static ssize_t scaling_boost_frequencies_show(struct cpufreq_policy *policy,
					      char *buf)
{
	return show_available_freqs(policy, buf, true);
}
cpufreq_attr_available_freq(scaling_boost);
EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_boost_freqs);

struct freq_attr *cpufreq_generic_attr[] = {
	&cpufreq_freq_attr_scaling_available_freqs,
#ifdef CONFIG_CPU_FREQ_BOOST_SW
	&cpufreq_freq_attr_scaling_boost_freqs,
#endif
	NULL,
};
EXPORT_SYMBOL_GPL(cpufreq_generic_attr);

/*
 * if you use these, you must assure that the frequency table is valid
 * all the time between get_attr and put_attr!
 */
void cpufreq_frequency_table_get_attr(struct cpufreq_frequency_table *table,
				      unsigned int cpu)
{
	pr_debug("setting show_table for cpu %u to %p\n", cpu, table);
	per_cpu(cpufreq_show_table, cpu) = table;
}
EXPORT_SYMBOL_GPL(cpufreq_frequency_table_get_attr);

void cpufreq_frequency_table_put_attr(unsigned int cpu)
{
	pr_debug("clearing show_table for cpu %u\n", cpu);
	per_cpu(cpufreq_show_table, cpu) = NULL;
}
EXPORT_SYMBOL_GPL(cpufreq_frequency_table_put_attr);

int cpufreq_table_validate_and_show(struct cpufreq_policy *policy,
				      struct cpufreq_frequency_table *table)
{
	int ret = cpufreq_frequency_table_cpuinfo(policy, table);

	if (!ret)
		cpufreq_frequency_table_get_attr(table, policy->cpu);

	return ret;
}
EXPORT_SYMBOL_GPL(cpufreq_table_validate_and_show);

void cpufreq_frequency_table_update_policy_cpu(struct cpufreq_policy *policy)
{
	pr_debug("Updating show_table for new_cpu %u from last_cpu %u\n",
			policy->cpu, policy->last_cpu);
	per_cpu(cpufreq_show_table, policy->cpu) = per_cpu(cpufreq_show_table,
			policy->last_cpu);
	per_cpu(cpufreq_show_table, policy->last_cpu) = NULL;
}

struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu)
{
	return per_cpu(cpufreq_show_table, cpu);
}
EXPORT_SYMBOL_GPL(cpufreq_frequency_get_table);

MODULE_AUTHOR("Dominik Brodowski <linux@brodo.de>");
MODULE_DESCRIPTION("CPUfreq frequency table helpers");
MODULE_LICENSE("GPL");