[linux-2.6-block.git] / drivers / cpufreq / freq_table.c

/*
 * linux/drivers/cpufreq/freq_table.c
 *
 * Copyright (C) 2002 - 2003 Dominik Brodowski
 */

#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 struct cpufreq_frequency_table *show_table[NR_CPUS];
/**
 * show_scaling_governor - show the current policy 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 (!show_table[cpu])
		return -ENODEV;

	table = 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);
	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);
	show_table[cpu] = NULL;
}
EXPORT_SYMBOL_GPL(cpufreq_frequency_table_put_attr);

struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu)
{
	return 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
	5	*/
	6
	7	#include <linux/kernel.h>
	8	#include <linux/module.h>
	9	#include <linux/init.h>
	10	#include <linux/cpufreq.h>
	11
e08f5f5b GS	12	#define dprintk(msg...) \
e08f5f5b GS	13	cpufreq_debug_printk(CPUFREQ_DEBUG_CORE, "freq-table", msg)
1da177e4 LT	14
	15	/*********************************************************************
	16	* FREQUENCY TABLE HELPERS *
	17	*********************************************************************/
	18
	19	int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
	20	struct cpufreq_frequency_table *table)
	21	{
	22	unsigned int min_freq = ~0;
	23	unsigned int max_freq = 0;
355eb318	24	unsigned int i;
1da177e4 LT	25
	26	for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
	27	unsigned int freq = table[i].frequency;
	28	if (freq == CPUFREQ_ENTRY_INVALID) {
	29	dprintk("table entry %u is invalid, skipping\n", i);
	30
	31	continue;
	32	}
e08f5f5b GS	33	dprintk("table entry %u: %u kHz, %u index\n",
e08f5f5b GS	34	i, freq, table[i].index);
1da177e4 LT	35	if (freq < min_freq)
	36	min_freq = freq;
	37	if (freq > max_freq)
	38	max_freq = freq;
	39	}
	40
	41	policy->min = policy->cpuinfo.min_freq = min_freq;
	42	policy->max = policy->cpuinfo.max_freq = max_freq;
	43
	44	if (policy->min == ~0)
	45	return -EINVAL;
	46	else
	47	return 0;
	48	}
	49	EXPORT_SYMBOL_GPL(cpufreq_frequency_table_cpuinfo);
	50
	51
	52	int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
	53	struct cpufreq_frequency_table *table)
	54	{
	55	unsigned int next_larger = ~0;
5557976c	56	unsigned int i;
1da177e4 LT	57	unsigned int count = 0;
1da177e4 LT	58
e08f5f5b GS	59	dprintk("request for verification of policy (%u - %u kHz) for cpu %u\n",
e08f5f5b GS	60	policy->min, policy->max, policy->cpu);
1da177e4 LT	61
	62	if (!cpu_online(policy->cpu))
	63	return -EINVAL;
	64
e08f5f5b GS	65	cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
e08f5f5b GS	66	policy->cpuinfo.max_freq);
1da177e4 LT	67
	68	for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
	69	unsigned int freq = table[i].frequency;
	70	if (freq == CPUFREQ_ENTRY_INVALID)
	71	continue;
	72	if ((freq >= policy->min) && (freq <= policy->max))
	73	count++;
	74	else if ((next_larger > freq) && (freq > policy->max))
	75	next_larger = freq;
	76	}
	77
	78	if (!count)
	79	policy->max = next_larger;
	80
e08f5f5b GS	81	cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
e08f5f5b GS	82	policy->cpuinfo.max_freq);
1da177e4	83
e08f5f5b GS	84	dprintk("verification lead to (%u - %u kHz) for cpu %u\n",
e08f5f5b GS	85	policy->min, policy->max, policy->cpu);
1da177e4 LT	86
	87	return 0;
	88	}
	89	EXPORT_SYMBOL_GPL(cpufreq_frequency_table_verify);
	90
	91
	92	int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
	93	struct cpufreq_frequency_table *table,
	94	unsigned int target_freq,
	95	unsigned int relation,
	96	unsigned int *index)
	97	{
484944a5 DJ	98	struct cpufreq_frequency_table optimal = {
	99	.index = ~0,
	100	.frequency = 0,
	101	};
	102	struct cpufreq_frequency_table suboptimal = {
	103	.index = ~0,
	104	.frequency = 0,
	105	};
1da177e4 LT	106	unsigned int i;
1da177e4 LT	107
e08f5f5b GS	108	dprintk("request for target %u kHz (relation: %u) for cpu %u\n",
e08f5f5b GS	109	target_freq, relation, policy->cpu);
1da177e4 LT	110
	111	switch (relation) {
	112	case CPUFREQ_RELATION_H:
1da177e4 LT	113	suboptimal.frequency = ~0;
	114	break;
	115	case CPUFREQ_RELATION_L:
	116	optimal.frequency = ~0;
1da177e4 LT	117	break;
	118	}
	119
	120	if (!cpu_online(policy->cpu))
	121	return -EINVAL;
	122
	123	for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
	124	unsigned int freq = table[i].frequency;
	125	if (freq == CPUFREQ_ENTRY_INVALID)
	126	continue;
	127	if ((freq < policy->min) \|\| (freq > policy->max))
	128	continue;
	129	switch(relation) {
	130	case CPUFREQ_RELATION_H:
	131	if (freq <= target_freq) {
	132	if (freq >= optimal.frequency) {
	133	optimal.frequency = freq;
	134	optimal.index = i;
	135	}
	136	} else {
	137	if (freq <= suboptimal.frequency) {
	138	suboptimal.frequency = freq;
	139	suboptimal.index = i;
	140	}
	141	}
	142	break;
	143	case CPUFREQ_RELATION_L:
	144	if (freq >= target_freq) {
	145	if (freq <= optimal.frequency) {
	146	optimal.frequency = freq;
	147	optimal.index = i;
	148	}
	149	} else {
	150	if (freq >= suboptimal.frequency) {
	151	suboptimal.frequency = freq;
	152	suboptimal.index = i;
	153	}
	154	}
	155	break;
	156	}
	157	}
	158	if (optimal.index > i) {
	159	if (suboptimal.index > i)
	160	return -EINVAL;
	161	*index = suboptimal.index;
	162	} else
	163	*index = optimal.index;
	164
	165	dprintk("target is %u (%u kHz, %u)\n", index, table[index].frequency,
	166	table[*index].index);
	167
	168	return 0;
	169	}
	170	EXPORT_SYMBOL_GPL(cpufreq_frequency_table_target);
	171
	172	static struct cpufreq_frequency_table *show_table[NR_CPUS];
	173	/**
	174	* show_scaling_governor - show the current policy for the specified CPU
	175	*/
	176	static ssize_t show_available_freqs (struct cpufreq_policy policy, char buf)
	177	{
	178	unsigned int i = 0;
	179	unsigned int cpu = policy->cpu;
	180	ssize_t count = 0;
181	struct cpufreq_frequency_table *table;
182
183	if (!show_table[cpu])
184	return -ENODEV;
185
186	table = show_table[cpu];
187
188	for (i=0; (table[i].frequency != CPUFREQ_TABLE_END); i++) {
189	if (table[i].frequency == CPUFREQ_ENTRY_INVALID)
190	continue;
191	count += sprintf(&buf[count], "%d ", table[i].frequency);
192	}
193	count += sprintf(&buf[count], "\n");
194
195	return count;
196
197	}
198
199	struct freq_attr cpufreq_freq_attr_scaling_available_freqs = {
e08f5f5b GS	200	.attr = { .name = "scaling_available_frequencies",
e08f5f5b GS	201	.mode = 0444,
e08f5f5b	202	},
1da177e4 LT	203	.show = show_available_freqs,
	204	};
	205	EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_available_freqs);
	206
	207	/*
	208	* if you use these, you must assure that the frequency table is valid
	209	* all the time between get_attr and put_attr!
	210	*/
32ee8c3e	211	void cpufreq_frequency_table_get_attr(struct cpufreq_frequency_table *table,
1da177e4 LT	212	unsigned int cpu)
	213	{
	214	dprintk("setting show_table for cpu %u to %p\n", cpu, table);
	215	show_table[cpu] = table;
	216	}
	217	EXPORT_SYMBOL_GPL(cpufreq_frequency_table_get_attr);
	218
	219	void cpufreq_frequency_table_put_attr(unsigned int cpu)
	220	{
	221	dprintk("clearing show_table for cpu %u\n", cpu);
	222	show_table[cpu] = NULL;
	223	}
	224	EXPORT_SYMBOL_GPL(cpufreq_frequency_table_put_attr);
	225
	226	struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu)
	227	{
	228	return show_table[cpu];
	229	}
	230	EXPORT_SYMBOL_GPL(cpufreq_frequency_get_table);
	231
	232	MODULE_AUTHOR ("Dominik Brodowski <linux@brodo.de>");
	233	MODULE_DESCRIPTION ("CPUfreq frequency table helpers");
	234	MODULE_LICENSE ("GPL");