1/*
2 * linux/drivers/cpufreq/freq_table.c
3 *
4 * Copyright (C) 2002 - 2003 Dominik Brodowski
5 *
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.
9 *
10 */
11
12#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13
14#include <linux/cpufreq.h>
15#include <linux/module.h>
16
17/*********************************************************************
18 *                     FREQUENCY TABLE HELPERS                       *
19 *********************************************************************/
20
21int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
22				    struct cpufreq_frequency_table *table)
23{
24	struct cpufreq_frequency_table *pos;
25	unsigned int min_freq = ~0;
26	unsigned int max_freq = 0;
27	unsigned int freq;
28
29	cpufreq_for_each_valid_entry(pos, table) {
30		freq = pos->frequency;
31
32		if (!cpufreq_boost_enabled()
33		    && (pos->flags & CPUFREQ_BOOST_FREQ))
34			continue;
35
36		pr_debug("table entry %u: %u kHz\n", (int)(pos - table), freq);
37		if (freq < min_freq)
38			min_freq = freq;
39		if (freq > max_freq)
40			max_freq = freq;
41	}
42
43	policy->min = policy->cpuinfo.min_freq = min_freq;
44	policy->max = policy->cpuinfo.max_freq = max_freq;
45
46	if (policy->min == ~0)
47		return -EINVAL;
48	else
49		return 0;
50}
51EXPORT_SYMBOL_GPL(cpufreq_frequency_table_cpuinfo);
52
53
54int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
55				   struct cpufreq_frequency_table *table)
56{
57	struct cpufreq_frequency_table *pos;
58	unsigned int freq, next_larger = ~0;
59	bool found = false;
60
61	pr_debug("request for verification of policy (%u - %u kHz) for cpu %u\n",
62					policy->min, policy->max, policy->cpu);
63
64	cpufreq_verify_within_cpu_limits(policy);
65
66	cpufreq_for_each_valid_entry(pos, table) {
67		freq = pos->frequency;
68
69		if ((freq >= policy->min) && (freq <= policy->max)) {
70			found = true;
71			break;
72		}
73
74		if ((next_larger > freq) && (freq > policy->max))
75			next_larger = freq;
76	}
77
78	if (!found) {
79		policy->max = next_larger;
80		cpufreq_verify_within_cpu_limits(policy);
81	}
82
83	pr_debug("verification lead to (%u - %u kHz) for cpu %u\n",
84				policy->min, policy->max, policy->cpu);
85
86	return 0;
87}
88EXPORT_SYMBOL_GPL(cpufreq_frequency_table_verify);
89
90/*
91 * Generic routine to verify policy & frequency table, requires driver to set
92 * policy->freq_table prior to it.
93 */
94int cpufreq_generic_frequency_table_verify(struct cpufreq_policy *policy)
95{
96	struct cpufreq_frequency_table *table =
97		cpufreq_frequency_get_table(policy->cpu);
98	if (!table)
99		return -ENODEV;
100
101	return cpufreq_frequency_table_verify(policy, table);
102}
103EXPORT_SYMBOL_GPL(cpufreq_generic_frequency_table_verify);
104
105int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
106				   struct cpufreq_frequency_table *table,
107				   unsigned int target_freq,
108				   unsigned int relation,
109				   unsigned int *index)
110{
111	struct cpufreq_frequency_table optimal = {
112		.driver_data = ~0,
113		.frequency = 0,
114	};
115	struct cpufreq_frequency_table suboptimal = {
116		.driver_data = ~0,
117		.frequency = 0,
118	};
119	struct cpufreq_frequency_table *pos;
120	unsigned int freq, diff, i = 0;
121
122	pr_debug("request for target %u kHz (relation: %u) for cpu %u\n",
123					target_freq, relation, policy->cpu);
124
125	switch (relation) {
126	case CPUFREQ_RELATION_H:
127		suboptimal.frequency = ~0;
128		break;
129	case CPUFREQ_RELATION_L:
130	case CPUFREQ_RELATION_C:
131		optimal.frequency = ~0;
132		break;
133	}
134
135	cpufreq_for_each_valid_entry(pos, table) {
136		freq = pos->frequency;
137
138		i = pos - table;
139		if ((freq < policy->min) || (freq > policy->max))
140			continue;
141		if (freq == target_freq) {
142			optimal.driver_data = i;
143			break;
144		}
145		switch (relation) {
146		case CPUFREQ_RELATION_H:
147			if (freq < target_freq) {
148				if (freq >= optimal.frequency) {
149					optimal.frequency = freq;
150					optimal.driver_data = i;
151				}
152			} else {
153				if (freq <= suboptimal.frequency) {
154					suboptimal.frequency = freq;
155					suboptimal.driver_data = i;
156				}
157			}
158			break;
159		case CPUFREQ_RELATION_L:
160			if (freq > target_freq) {
161				if (freq <= optimal.frequency) {
162					optimal.frequency = freq;
163					optimal.driver_data = i;
164				}
165			} else {
166				if (freq >= suboptimal.frequency) {
167					suboptimal.frequency = freq;
168					suboptimal.driver_data = i;
169				}
170			}
171			break;
172		case CPUFREQ_RELATION_C:
173			diff = abs(freq - target_freq);
174			if (diff < optimal.frequency ||
175			    (diff == optimal.frequency &&
176			     freq > table[optimal.driver_data].frequency)) {
177				optimal.frequency = diff;
178				optimal.driver_data = i;
179			}
180			break;
181		}
182	}
183	if (optimal.driver_data > i) {
184		if (suboptimal.driver_data > i)
185			return -EINVAL;
186		*index = suboptimal.driver_data;
187	} else
188		*index = optimal.driver_data;
189
190	pr_debug("target index is %u, freq is:%u kHz\n", *index,
191		 table[*index].frequency);
192
193	return 0;
194}
195EXPORT_SYMBOL_GPL(cpufreq_frequency_table_target);
196
197int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy,
198		unsigned int freq)
199{
200	struct cpufreq_frequency_table *pos, *table;
201
202	table = cpufreq_frequency_get_table(policy->cpu);
203	if (unlikely(!table)) {
204		pr_debug("%s: Unable to find frequency table\n", __func__);
205		return -ENOENT;
206	}
207
208	cpufreq_for_each_valid_entry(pos, table)
209		if (pos->frequency == freq)
210			return pos - table;
211
212	return -EINVAL;
213}
214EXPORT_SYMBOL_GPL(cpufreq_frequency_table_get_index);
215
216/**
217 * show_available_freqs - show available frequencies for the specified CPU
218 */
219static ssize_t show_available_freqs(struct cpufreq_policy *policy, char *buf,
220				    bool show_boost)
221{
222	ssize_t count = 0;
223	struct cpufreq_frequency_table *pos, *table = policy->freq_table;
224
225	if (!table)
226		return -ENODEV;
227
228	cpufreq_for_each_valid_entry(pos, table) {
229		/*
230		 * show_boost = true and driver_data = BOOST freq
231		 * display BOOST freqs
232		 *
233		 * show_boost = false and driver_data = BOOST freq
234		 * show_boost = true and driver_data != BOOST freq
235		 * continue - do not display anything
236		 *
237		 * show_boost = false and driver_data != BOOST freq
238		 * display NON BOOST freqs
239		 */
240		if (show_boost ^ (pos->flags & CPUFREQ_BOOST_FREQ))
241			continue;
242
243		count += sprintf(&buf[count], "%d ", pos->frequency);
244	}
245	count += sprintf(&buf[count], "\n");
246
247	return count;
248
249}
250
251#define cpufreq_attr_available_freq(_name)	  \
252struct freq_attr cpufreq_freq_attr_##_name##_freqs =     \
253__ATTR_RO(_name##_frequencies)
254
255/**
256 * show_scaling_available_frequencies - show available normal frequencies for
257 * the specified CPU
258 */
259static ssize_t scaling_available_frequencies_show(struct cpufreq_policy *policy,
260						  char *buf)
261{
262	return show_available_freqs(policy, buf, false);
263}
264cpufreq_attr_available_freq(scaling_available);
265EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_available_freqs);
266
267/**
268 * show_available_boost_freqs - show available boost frequencies for
269 * the specified CPU
270 */
271static ssize_t scaling_boost_frequencies_show(struct cpufreq_policy *policy,
272					      char *buf)
273{
274	return show_available_freqs(policy, buf, true);
275}
276cpufreq_attr_available_freq(scaling_boost);
277EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_boost_freqs);
278
279struct freq_attr *cpufreq_generic_attr[] = {
280	&cpufreq_freq_attr_scaling_available_freqs,
281#ifdef CONFIG_CPU_FREQ_BOOST_SW
282	&cpufreq_freq_attr_scaling_boost_freqs,
283#endif
284	NULL,
285};
286EXPORT_SYMBOL_GPL(cpufreq_generic_attr);
287
288int cpufreq_table_validate_and_show(struct cpufreq_policy *policy,
289				      struct cpufreq_frequency_table *table)
290{
291	int ret = cpufreq_frequency_table_cpuinfo(policy, table);
292
293	if (!ret)
294		policy->freq_table = table;
295
296	return ret;
297}
298EXPORT_SYMBOL_GPL(cpufreq_table_validate_and_show);
299
300struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu);
301
302struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu)
303{
304	struct cpufreq_policy *policy = cpufreq_cpu_get_raw(cpu);
305	return policy ? policy->freq_table : NULL;
306}
307EXPORT_SYMBOL_GPL(cpufreq_frequency_get_table);
308
309MODULE_AUTHOR("Dominik Brodowski <linux@brodo.de>");
310MODULE_DESCRIPTION("CPUfreq frequency table helpers");
311MODULE_LICENSE("GPL");
312