[mirror_ubuntu-bionic-kernel.git] / drivers / cpufreq / freq_table.c

/*
 * 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;
		}
		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);

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

	return count;

}

struct freq_attr cpufreq_freq_attr_scaling_available_freqs = {
	.attr = { .name = "scaling_available_frequencies",
		  .mode = 0444,
		},
	.show = show_available_freqs,
};
EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_available_freqs);

struct freq_attr *cpufreq_generic_attr[] = {
	&cpufreq_freq_attr_scaling_available_freqs,
	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");
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/drivers/cpufreq/freq_table.c
	3	*
	4	* Copyright (C) 2002 - 2003 Dominik Brodowski
4f743694 DB	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	*
1da177e4 LT	10	*/
1da177e4 LT	11
db701151 VK	12	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
db701151 VK	13
1da177e4	14	#include <linux/cpufreq.h>
5ff0a268	15	#include <linux/module.h>
1da177e4	16
1da177e4 LT	17	/*********************************************************************
	18	* FREQUENCY TABLE HELPERS *
	19	*********************************************************************/
	20
	21	int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
	22	struct cpufreq_frequency_table *table)
	23	{
	24	unsigned int min_freq = ~0;
	25	unsigned int max_freq = 0;
355eb318	26	unsigned int i;
1da177e4	27
97acec55	28	for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
1da177e4 LT	29	unsigned int freq = table[i].frequency;
1da177e4 LT	30	if (freq == CPUFREQ_ENTRY_INVALID) {
2d06d8c4	31	pr_debug("table entry %u is invalid, skipping\n", i);
1da177e4 LT	32
	33	continue;
	34	}
50701588 VK	35	pr_debug("table entry %u: %u kHz, %u driver_data\n",
50701588 VK	36	i, freq, table[i].driver_data);
1da177e4 LT	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	}
	51	EXPORT_SYMBOL_GPL(cpufreq_frequency_table_cpuinfo);
	52
	53
	54	int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
	55	struct cpufreq_frequency_table *table)
	56	{
77db50c4 VK	57	unsigned int next_larger = ~0, freq, i = 0;
77db50c4 VK	58	bool found = false;
1da177e4	59
2d06d8c4	60	pr_debug("request for verification of policy (%u - %u kHz) for cpu %u\n",
e08f5f5b	61	policy->min, policy->max, policy->cpu);
1da177e4	62
be49e346	63	cpufreq_verify_within_cpu_limits(policy);
1da177e4	64
77db50c4	65	for (; freq = table[i].frequency, freq != CPUFREQ_TABLE_END; i++) {
1da177e4 LT	66	if (freq == CPUFREQ_ENTRY_INVALID)
1da177e4 LT	67	continue;
77db50c4 VK	68	if ((freq >= policy->min) && (freq <= policy->max)) {
	69	found = true;
	70	break;
	71	}
	72
	73	if ((next_larger > freq) && (freq > policy->max))
1da177e4 LT	74	next_larger = freq;
	75	}
	76
77db50c4	77	if (!found) {
1da177e4	78	policy->max = next_larger;
be49e346	79	cpufreq_verify_within_cpu_limits(policy);
77db50c4	80	}
1da177e4	81
2d06d8c4	82	pr_debug("verification lead to (%u - %u kHz) for cpu %u\n",
e08f5f5b	83	policy->min, policy->max, policy->cpu);
1da177e4 LT	84
	85	return 0;
	86	}
	87	EXPORT_SYMBOL_GPL(cpufreq_frequency_table_verify);
	88
18434512 VK	89	/*
	90	* Generic routine to verify policy & frequency table, requires driver to call
	91	* cpufreq_frequency_table_get_attr() prior to it.
	92	*/
	93	int cpufreq_generic_frequency_table_verify(struct cpufreq_policy *policy)
	94	{
	95	struct cpufreq_frequency_table *table =
	96	cpufreq_frequency_get_table(policy->cpu);
	97	if (!table)
	98	return -ENODEV;
	99
	100	return cpufreq_frequency_table_verify(policy, table);
	101	}
	102	EXPORT_SYMBOL_GPL(cpufreq_generic_frequency_table_verify);
1da177e4 LT	103
	104	int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
	105	struct cpufreq_frequency_table *table,
	106	unsigned int target_freq,
	107	unsigned int relation,
	108	unsigned int *index)
	109	{
484944a5	110	struct cpufreq_frequency_table optimal = {
50701588	111	.driver_data = ~0,
484944a5 DJ	112	.frequency = 0,
	113	};
	114	struct cpufreq_frequency_table suboptimal = {
50701588	115	.driver_data = ~0,
484944a5 DJ	116	.frequency = 0,
484944a5 DJ	117	};
1da177e4 LT	118	unsigned int i;
1da177e4 LT	119
2d06d8c4	120	pr_debug("request for target %u kHz (relation: %u) for cpu %u\n",
e08f5f5b	121	target_freq, relation, policy->cpu);
1da177e4 LT	122
	123	switch (relation) {
	124	case CPUFREQ_RELATION_H:
1da177e4 LT	125	suboptimal.frequency = ~0;
	126	break;
	127	case CPUFREQ_RELATION_L:
	128	optimal.frequency = ~0;
1da177e4 LT	129	break;
	130	}
	131
97acec55	132	for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
1da177e4 LT	133	unsigned int freq = table[i].frequency;
	134	if (freq == CPUFREQ_ENTRY_INVALID)
	135	continue;
	136	if ((freq < policy->min) \|\| (freq > policy->max))
	137	continue;
97acec55	138	switch (relation) {
1da177e4 LT	139	case CPUFREQ_RELATION_H:
	140	if (freq <= target_freq) {
	141	if (freq >= optimal.frequency) {
	142	optimal.frequency = freq;
50701588	143	optimal.driver_data = i;
1da177e4 LT	144	}
	145	} else {
	146	if (freq <= suboptimal.frequency) {
	147	suboptimal.frequency = freq;
50701588	148	suboptimal.driver_data = i;
1da177e4 LT	149	}
	150	}
	151	break;
	152	case CPUFREQ_RELATION_L:
	153	if (freq >= target_freq) {
	154	if (freq <= optimal.frequency) {
	155	optimal.frequency = freq;
50701588	156	optimal.driver_data = i;
1da177e4 LT	157	}
	158	} else {
	159	if (freq >= suboptimal.frequency) {
	160	suboptimal.frequency = freq;
50701588	161	suboptimal.driver_data = i;
1da177e4 LT	162	}
	163	}
	164	break;
	165	}
	166	}
50701588 VK	167	if (optimal.driver_data > i) {
50701588 VK	168	if (suboptimal.driver_data > i)
1da177e4	169	return -EINVAL;
50701588	170	*index = suboptimal.driver_data;
1da177e4	171	} else
50701588	172	*index = optimal.driver_data;
1da177e4	173
2d06d8c4	174	pr_debug("target is %u (%u kHz, %u)\n", index, table[index].frequency,
50701588	175	table[*index].driver_data);
1da177e4 LT	176
	177	return 0;
	178	}
	179	EXPORT_SYMBOL_GPL(cpufreq_frequency_table_target);
	180
f1625066	181	static DEFINE_PER_CPU(struct cpufreq_frequency_table *, cpufreq_show_table);
1da177e4	182	/**
e32d22f7	183	* show_available_freqs - show available frequencies for the specified CPU
1da177e4	184	*/
97acec55	185	static ssize_t show_available_freqs(struct cpufreq_policy policy, char buf)
1da177e4 LT	186	{
	187	unsigned int i = 0;
	188	unsigned int cpu = policy->cpu;
	189	ssize_t count = 0;
	190	struct cpufreq_frequency_table *table;
	191
f1625066	192	if (!per_cpu(cpufreq_show_table, cpu))
1da177e4 LT	193	return -ENODEV;
1da177e4 LT	194
f1625066	195	table = per_cpu(cpufreq_show_table, cpu);
1da177e4	196
97acec55	197	for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
1da177e4 LT	198	if (table[i].frequency == CPUFREQ_ENTRY_INVALID)
	199	continue;
	200	count += sprintf(&buf[count], "%d ", table[i].frequency);
	201	}
	202	count += sprintf(&buf[count], "\n");
	203
	204	return count;
	205
	206	}
	207
	208	struct freq_attr cpufreq_freq_attr_scaling_available_freqs = {
e08f5f5b GS	209	.attr = { .name = "scaling_available_frequencies",
e08f5f5b GS	210	.mode = 0444,
e08f5f5b	211	},
1da177e4 LT	212	.show = show_available_freqs,
	213	};
	214	EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_available_freqs);
	215
18434512 VK	216	struct freq_attr *cpufreq_generic_attr[] = {
	217	&cpufreq_freq_attr_scaling_available_freqs,
	218	NULL,
	219	};
	220	EXPORT_SYMBOL_GPL(cpufreq_generic_attr);
	221
1da177e4 LT	222	/*
	223	* if you use these, you must assure that the frequency table is valid
	224	* all the time between get_attr and put_attr!
	225	*/
32ee8c3e	226	void cpufreq_frequency_table_get_attr(struct cpufreq_frequency_table *table,
1da177e4 LT	227	unsigned int cpu)
1da177e4 LT	228	{
2d06d8c4	229	pr_debug("setting show_table for cpu %u to %p\n", cpu, table);
f1625066	230	per_cpu(cpufreq_show_table, cpu) = table;
1da177e4 LT	231	}
	232	EXPORT_SYMBOL_GPL(cpufreq_frequency_table_get_attr);
	233
	234	void cpufreq_frequency_table_put_attr(unsigned int cpu)
	235	{
2d06d8c4	236	pr_debug("clearing show_table for cpu %u\n", cpu);
f1625066	237	per_cpu(cpufreq_show_table, cpu) = NULL;
1da177e4 LT	238	}
	239	EXPORT_SYMBOL_GPL(cpufreq_frequency_table_put_attr);
	240
27047a60 VK	241	int cpufreq_table_validate_and_show(struct cpufreq_policy *policy,
	242	struct cpufreq_frequency_table *table)
	243	{
	244	int ret = cpufreq_frequency_table_cpuinfo(policy, table);
	245
	246	if (!ret)
	247	cpufreq_frequency_table_get_attr(table, policy->cpu);
	248
	249	return ret;
	250	}
	251	EXPORT_SYMBOL_GPL(cpufreq_table_validate_and_show);
	252
b8eed8af VK	253	void cpufreq_frequency_table_update_policy_cpu(struct cpufreq_policy *policy)
	254	{
	255	pr_debug("Updating show_table for new_cpu %u from last_cpu %u\n",
	256	policy->cpu, policy->last_cpu);
	257	per_cpu(cpufreq_show_table, policy->cpu) = per_cpu(cpufreq_show_table,
	258	policy->last_cpu);
	259	per_cpu(cpufreq_show_table, policy->last_cpu) = NULL;
	260	}
	261
1da177e4 LT	262	struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu)
1da177e4 LT	263	{
f1625066	264	return per_cpu(cpufreq_show_table, cpu);
1da177e4 LT	265	}
	266	EXPORT_SYMBOL_GPL(cpufreq_frequency_get_table);
	267
97acec55 DJ	268	MODULE_AUTHOR("Dominik Brodowski <linux@brodo.de>");
	269	MODULE_DESCRIPTION("CPUfreq frequency table helpers");
	270	MODULE_LICENSE("GPL");