[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.
 *
 */

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

#define dprintk(msg...) \
	cpufreq_debug_printk(CPUFREQ_DEBUG_CORE, "freq-table", msg)

/*********************************************************************
 *                     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) {
			dprintk("table entry %u is invalid, skipping\n", i);

			continue;
		}
		dprintk("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;

	dprintk("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);

	dprintk("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;

	dprintk("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;

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