[deliverable/linux.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.
 *
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/cpufreq.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 index\n",
					i, freq, table[i].index);
		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;
	unsigned int i;
	unsigned int count = 0;

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

	if (!cpu_online(policy->cpu))
		return -EINVAL;

	cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
				     policy->cpuinfo.max_freq);

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

	if (!count)
		policy->max = next_larger;

	cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
				     policy->cpuinfo.max_freq);

	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);


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 = {
		.index = ~0,
		.frequency = 0,
	};
	struct cpufreq_frequency_table suboptimal = {
		.index = ~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;
	}

	if (!cpu_online(policy->cpu))
		return -EINVAL;

	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.index = i;
				}
			} else {
				if (freq <= suboptimal.frequency) {
					suboptimal.frequency = freq;
					suboptimal.index = i;
				}
			}
			break;
		case CPUFREQ_RELATION_L:
			if (freq >= target_freq) {
				if (freq <= optimal.frequency) {
					optimal.frequency = freq;
					optimal.index = i;
				}
			} else {
				if (freq >= suboptimal.frequency) {
					suboptimal.frequency = freq;
					suboptimal.index = i;
				}
			}
			break;
		}
	}
	if (optimal.index > i) {
		if (suboptimal.index > i)
			return -EINVAL;
		*index = suboptimal.index;
	} else
		*index = optimal.index;

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

	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);

/*
 * 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);

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	*/
	11
	12	#include <linux/kernel.h>
	13	#include <linux/module.h>
	14	#include <linux/init.h>
	15	#include <linux/cpufreq.h>
	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	}
2d06d8c4	35	pr_debug("table entry %u: %u kHz, %u index\n",
e08f5f5b	36	i, freq, table[i].index);
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	{
	57	unsigned int next_larger = ~0;
5557976c	58	unsigned int i;
1da177e4 LT	59	unsigned int count = 0;
1da177e4 LT	60
2d06d8c4	61	pr_debug("request for verification of policy (%u - %u kHz) for cpu %u\n",
e08f5f5b	62	policy->min, policy->max, policy->cpu);
1da177e4 LT	63
	64	if (!cpu_online(policy->cpu))
	65	return -EINVAL;
	66
e08f5f5b GS	67	cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
e08f5f5b GS	68	policy->cpuinfo.max_freq);
1da177e4	69
97acec55	70	for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
1da177e4 LT	71	unsigned int freq = table[i].frequency;
	72	if (freq == CPUFREQ_ENTRY_INVALID)
	73	continue;
	74	if ((freq >= policy->min) && (freq <= policy->max))
	75	count++;
	76	else if ((next_larger > freq) && (freq > policy->max))
	77	next_larger = freq;
	78	}
	79
	80	if (!count)
	81	policy->max = next_larger;
	82
e08f5f5b GS	83	cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
e08f5f5b GS	84	policy->cpuinfo.max_freq);
1da177e4	85
2d06d8c4	86	pr_debug("verification lead to (%u - %u kHz) for cpu %u\n",
e08f5f5b	87	policy->min, policy->max, policy->cpu);
1da177e4 LT	88
	89	return 0;
	90	}
	91	EXPORT_SYMBOL_GPL(cpufreq_frequency_table_verify);
	92
	93
	94	int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
	95	struct cpufreq_frequency_table *table,
	96	unsigned int target_freq,
	97	unsigned int relation,
	98	unsigned int *index)
	99	{
484944a5 DJ	100	struct cpufreq_frequency_table optimal = {
	101	.index = ~0,
	102	.frequency = 0,
	103	};
	104	struct cpufreq_frequency_table suboptimal = {
	105	.index = ~0,
	106	.frequency = 0,
	107	};
1da177e4 LT	108	unsigned int i;
1da177e4 LT	109
2d06d8c4	110	pr_debug("request for target %u kHz (relation: %u) for cpu %u\n",
e08f5f5b	111	target_freq, relation, policy->cpu);
1da177e4 LT	112
	113	switch (relation) {
	114	case CPUFREQ_RELATION_H:
1da177e4 LT	115	suboptimal.frequency = ~0;
	116	break;
	117	case CPUFREQ_RELATION_L:
	118	optimal.frequency = ~0;
1da177e4 LT	119	break;
	120	}
	121
	122	if (!cpu_online(policy->cpu))
	123	return -EINVAL;
	124
97acec55	125	for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
1da177e4 LT	126	unsigned int freq = table[i].frequency;
	127	if (freq == CPUFREQ_ENTRY_INVALID)
	128	continue;
	129	if ((freq < policy->min) \|\| (freq > policy->max))
	130	continue;
97acec55	131	switch (relation) {
1da177e4 LT	132	case CPUFREQ_RELATION_H:
	133	if (freq <= target_freq) {
	134	if (freq >= optimal.frequency) {
	135	optimal.frequency = freq;
	136	optimal.index = i;
	137	}
	138	} else {
	139	if (freq <= suboptimal.frequency) {
	140	suboptimal.frequency = freq;
	141	suboptimal.index = i;
	142	}
	143	}
	144	break;
	145	case CPUFREQ_RELATION_L:
	146	if (freq >= target_freq) {
	147	if (freq <= optimal.frequency) {
	148	optimal.frequency = freq;
	149	optimal.index = i;
	150	}
	151	} else {
	152	if (freq >= suboptimal.frequency) {
	153	suboptimal.frequency = freq;
	154	suboptimal.index = i;
	155	}
	156	}
	157	break;
	158	}
	159	}
	160	if (optimal.index > i) {
	161	if (suboptimal.index > i)
	162	return -EINVAL;
	163	*index = suboptimal.index;
	164	} else
	165	*index = optimal.index;
	166
2d06d8c4	167	pr_debug("target is %u (%u kHz, %u)\n", index, table[index].frequency,
1da177e4 LT	168	table[*index].index);
	169
	170	return 0;
	171	}
	172	EXPORT_SYMBOL_GPL(cpufreq_frequency_table_target);
	173
f1625066	174	static DEFINE_PER_CPU(struct cpufreq_frequency_table *, cpufreq_show_table);
1da177e4	175	/**
e32d22f7	176	* show_available_freqs - show available frequencies for the specified CPU
1da177e4	177	*/
97acec55	178	static ssize_t show_available_freqs(struct cpufreq_policy policy, char buf)
1da177e4 LT	179	{
	180	unsigned int i = 0;
	181	unsigned int cpu = policy->cpu;
	182	ssize_t count = 0;
	183	struct cpufreq_frequency_table *table;
	184
f1625066	185	if (!per_cpu(cpufreq_show_table, cpu))
1da177e4 LT	186	return -ENODEV;
1da177e4 LT	187
f1625066	188	table = per_cpu(cpufreq_show_table, cpu);
1da177e4	189
97acec55	190	for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
1da177e4 LT	191	if (table[i].frequency == CPUFREQ_ENTRY_INVALID)
	192	continue;
	193	count += sprintf(&buf[count], "%d ", table[i].frequency);
	194	}
	195	count += sprintf(&buf[count], "\n");
	196
	197	return count;
	198
	199	}
	200
	201	struct freq_attr cpufreq_freq_attr_scaling_available_freqs = {
e08f5f5b GS	202	.attr = { .name = "scaling_available_frequencies",
e08f5f5b GS	203	.mode = 0444,
e08f5f5b	204	},
1da177e4 LT	205	.show = show_available_freqs,
	206	};
	207	EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_available_freqs);
	208
	209	/*
	210	* if you use these, you must assure that the frequency table is valid
	211	* all the time between get_attr and put_attr!
	212	*/
32ee8c3e	213	void cpufreq_frequency_table_get_attr(struct cpufreq_frequency_table *table,
1da177e4 LT	214	unsigned int cpu)
1da177e4 LT	215	{
2d06d8c4	216	pr_debug("setting show_table for cpu %u to %p\n", cpu, table);
f1625066	217	per_cpu(cpufreq_show_table, cpu) = table;
1da177e4 LT	218	}
	219	EXPORT_SYMBOL_GPL(cpufreq_frequency_table_get_attr);
	220
	221	void cpufreq_frequency_table_put_attr(unsigned int cpu)
	222	{
2d06d8c4	223	pr_debug("clearing show_table for cpu %u\n", cpu);
f1625066	224	per_cpu(cpufreq_show_table, cpu) = NULL;
1da177e4 LT	225	}
	226	EXPORT_SYMBOL_GPL(cpufreq_frequency_table_put_attr);
	227
	228	struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu)
	229	{
f1625066	230	return per_cpu(cpufreq_show_table, cpu);
1da177e4 LT	231	}
	232	EXPORT_SYMBOL_GPL(cpufreq_frequency_get_table);
	233
97acec55 DJ	234	MODULE_AUTHOR("Dominik Brodowski <linux@brodo.de>");
	235	MODULE_DESCRIPTION("CPUfreq frequency table helpers");
	236	MODULE_LICENSE("GPL");