[linux-2.6-block.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/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	*/
1da177e4 LT	11
db701151 VK	12	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
db701151 VK	13
1da177e4 LT	14	#include <linux/kernel.h>
	15	#include <linux/module.h>
	16	#include <linux/init.h>
	17	#include <linux/cpufreq.h>
	18
1da177e4 LT	19	/*********************************************************************
	20	* FREQUENCY TABLE HELPERS *
	21	*********************************************************************/
	22
	23	int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
	24	struct cpufreq_frequency_table *table)
	25	{
	26	unsigned int min_freq = ~0;
	27	unsigned int max_freq = 0;
355eb318	28	unsigned int i;
1da177e4	29
97acec55	30	for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
1da177e4 LT	31	unsigned int freq = table[i].frequency;
1da177e4 LT	32	if (freq == CPUFREQ_ENTRY_INVALID) {
2d06d8c4	33	pr_debug("table entry %u is invalid, skipping\n", i);
1da177e4 LT	34
	35	continue;
	36	}
2d06d8c4	37	pr_debug("table entry %u: %u kHz, %u index\n",
e08f5f5b	38	i, freq, table[i].index);
1da177e4 LT	39	if (freq < min_freq)
	40	min_freq = freq;
	41	if (freq > max_freq)
	42	max_freq = freq;
	43	}
	44
	45	policy->min = policy->cpuinfo.min_freq = min_freq;
	46	policy->max = policy->cpuinfo.max_freq = max_freq;
	47
	48	if (policy->min == ~0)
	49	return -EINVAL;
	50	else
	51	return 0;
	52	}
	53	EXPORT_SYMBOL_GPL(cpufreq_frequency_table_cpuinfo);
	54
	55
	56	int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
	57	struct cpufreq_frequency_table *table)
	58	{
	59	unsigned int next_larger = ~0;
5557976c	60	unsigned int i;
1da177e4 LT	61	unsigned int count = 0;
1da177e4 LT	62
2d06d8c4	63	pr_debug("request for verification of policy (%u - %u kHz) for cpu %u\n",
e08f5f5b	64	policy->min, policy->max, policy->cpu);
1da177e4 LT	65
	66	if (!cpu_online(policy->cpu))
	67	return -EINVAL;
	68
e08f5f5b GS	69	cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
e08f5f5b GS	70	policy->cpuinfo.max_freq);
1da177e4	71
97acec55	72	for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
1da177e4 LT	73	unsigned int freq = table[i].frequency;
	74	if (freq == CPUFREQ_ENTRY_INVALID)
	75	continue;
	76	if ((freq >= policy->min) && (freq <= policy->max))
	77	count++;
	78	else if ((next_larger > freq) && (freq > policy->max))
	79	next_larger = freq;
	80	}
	81
	82	if (!count)
	83	policy->max = next_larger;
	84
e08f5f5b GS	85	cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
e08f5f5b GS	86	policy->cpuinfo.max_freq);
1da177e4	87
2d06d8c4	88	pr_debug("verification lead to (%u - %u kHz) for cpu %u\n",
e08f5f5b	89	policy->min, policy->max, policy->cpu);
1da177e4 LT	90
	91	return 0;
	92	}
	93	EXPORT_SYMBOL_GPL(cpufreq_frequency_table_verify);
	94
	95
	96	int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
	97	struct cpufreq_frequency_table *table,
	98	unsigned int target_freq,
	99	unsigned int relation,
	100	unsigned int *index)
	101	{
484944a5 DJ	102	struct cpufreq_frequency_table optimal = {
	103	.index = ~0,
	104	.frequency = 0,
	105	};
	106	struct cpufreq_frequency_table suboptimal = {
	107	.index = ~0,
	108	.frequency = 0,
	109	};
1da177e4 LT	110	unsigned int i;
1da177e4 LT	111
2d06d8c4	112	pr_debug("request for target %u kHz (relation: %u) for cpu %u\n",
e08f5f5b	113	target_freq, relation, policy->cpu);
1da177e4 LT	114
	115	switch (relation) {
	116	case CPUFREQ_RELATION_H:
1da177e4 LT	117	suboptimal.frequency = ~0;
	118	break;
	119	case CPUFREQ_RELATION_L:
	120	optimal.frequency = ~0;
1da177e4 LT	121	break;
	122	}
	123
	124	if (!cpu_online(policy->cpu))
	125	return -EINVAL;
	126
97acec55	127	for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
1da177e4 LT	128	unsigned int freq = table[i].frequency;
	129	if (freq == CPUFREQ_ENTRY_INVALID)
	130	continue;
	131	if ((freq < policy->min) \|\| (freq > policy->max))
	132	continue;
97acec55	133	switch (relation) {
1da177e4 LT	134	case CPUFREQ_RELATION_H:
	135	if (freq <= target_freq) {
	136	if (freq >= optimal.frequency) {
	137	optimal.frequency = freq;
	138	optimal.index = i;
	139	}
	140	} else {
	141	if (freq <= suboptimal.frequency) {
	142	suboptimal.frequency = freq;
	143	suboptimal.index = i;
	144	}
	145	}
	146	break;
	147	case CPUFREQ_RELATION_L:
	148	if (freq >= target_freq) {
	149	if (freq <= optimal.frequency) {
	150	optimal.frequency = freq;
	151	optimal.index = i;
	152	}
	153	} else {
	154	if (freq >= suboptimal.frequency) {
	155	suboptimal.frequency = freq;
	156	suboptimal.index = i;
	157	}
	158	}
	159	break;
	160	}
	161	}
	162	if (optimal.index > i) {
	163	if (suboptimal.index > i)
	164	return -EINVAL;
	165	*index = suboptimal.index;
	166	} else
	167	*index = optimal.index;
	168
2d06d8c4	169	pr_debug("target is %u (%u kHz, %u)\n", index, table[index].frequency,
1da177e4 LT	170	table[*index].index);
	171
	172	return 0;
	173	}
	174	EXPORT_SYMBOL_GPL(cpufreq_frequency_table_target);
	175
f1625066	176	static DEFINE_PER_CPU(struct cpufreq_frequency_table *, cpufreq_show_table);
1da177e4	177	/**
e32d22f7	178	* show_available_freqs - show available frequencies for the specified CPU
1da177e4	179	*/
97acec55	180	static ssize_t show_available_freqs(struct cpufreq_policy policy, char buf)
1da177e4 LT	181	{
	182	unsigned int i = 0;
	183	unsigned int cpu = policy->cpu;
	184	ssize_t count = 0;
	185	struct cpufreq_frequency_table *table;
	186
f1625066	187	if (!per_cpu(cpufreq_show_table, cpu))
1da177e4 LT	188	return -ENODEV;
1da177e4 LT	189
f1625066	190	table = per_cpu(cpufreq_show_table, cpu);
1da177e4	191
97acec55	192	for (i = 0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
1da177e4 LT	193	if (table[i].frequency == CPUFREQ_ENTRY_INVALID)
	194	continue;
	195	count += sprintf(&buf[count], "%d ", table[i].frequency);
	196	}
	197	count += sprintf(&buf[count], "\n");
	198
	199	return count;
	200
	201	}
	202
	203	struct freq_attr cpufreq_freq_attr_scaling_available_freqs = {
e08f5f5b GS	204	.attr = { .name = "scaling_available_frequencies",
e08f5f5b GS	205	.mode = 0444,
e08f5f5b	206	},
1da177e4 LT	207	.show = show_available_freqs,
	208	};
	209	EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_available_freqs);
	210
	211	/*
	212	* if you use these, you must assure that the frequency table is valid
	213	* all the time between get_attr and put_attr!
	214	*/
32ee8c3e	215	void cpufreq_frequency_table_get_attr(struct cpufreq_frequency_table *table,
1da177e4 LT	216	unsigned int cpu)
1da177e4 LT	217	{
2d06d8c4	218	pr_debug("setting show_table for cpu %u to %p\n", cpu, table);
f1625066	219	per_cpu(cpufreq_show_table, cpu) = table;
1da177e4 LT	220	}
	221	EXPORT_SYMBOL_GPL(cpufreq_frequency_table_get_attr);
	222
	223	void cpufreq_frequency_table_put_attr(unsigned int cpu)
	224	{
2d06d8c4	225	pr_debug("clearing show_table for cpu %u\n", cpu);
f1625066	226	per_cpu(cpufreq_show_table, cpu) = NULL;
1da177e4 LT	227	}
	228	EXPORT_SYMBOL_GPL(cpufreq_frequency_table_put_attr);
	229
	230	struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu)
	231	{
f1625066	232	return per_cpu(cpufreq_show_table, cpu);
1da177e4 LT	233	}
	234	EXPORT_SYMBOL_GPL(cpufreq_frequency_get_table);
	235
97acec55 DJ	236	MODULE_AUTHOR("Dominik Brodowski <linux@brodo.de>");
	237	MODULE_DESCRIPTION("CPUfreq frequency table helpers");
	238	MODULE_LICENSE("GPL");