drivers/cpufreq/freq_table.c - linux - Git at Google

 // SPDX-License-Identifier: GPL-2.0-only
 /*
  * linux/drivers/cpufreq/freq_table.c
  *
  * Copyright (C) 2002 - 2003 Dominik Brodowski
  */

 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

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

 /*********************************************************************
  *                     FREQUENCY TABLE HELPERS                       *
  *********************************************************************/

 bool policy_has_boost_freq(struct cpufreq_policy *policy)
 {
 	struct cpufreq_frequency_table *pos, *table = policy->freq_table;

 	if (!table)
 		return false;

 	cpufreq_for_each_valid_entry(pos, table)
 		if (pos->flags & CPUFREQ_BOOST_FREQ)
 			return true;

 	return false;
 }
 EXPORT_SYMBOL_GPL(policy_has_boost_freq);

 int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
 				    struct cpufreq_frequency_table *table)
 {
 	struct cpufreq_frequency_table *pos;
 	unsigned int min_freq = ~0;
 	unsigned int max_freq = 0;
 	unsigned int freq;

 	cpufreq_for_each_valid_entry(pos, table) {
 		freq = pos->frequency;

 		if ((!cpufreq_boost_enabled() || !policy->boost_enabled)
 		    && (pos->flags & CPUFREQ_BOOST_FREQ))
 			continue;

 		pr_debug("table entry %u: %u kHz\n", (int)(pos - table), freq);
 		if (freq < min_freq)
 			min_freq = freq;
 		if (freq > max_freq)
 			max_freq = freq;
 	}

 	policy->min = policy->cpuinfo.min_freq = min_freq;
 	policy->max = max_freq;
 	/*
 	 * If the driver has set its own cpuinfo.max_freq above max_freq, leave
 	 * it as is.
 	 */
 	if (policy->cpuinfo.max_freq < max_freq)
 		policy->max = policy->cpuinfo.max_freq = max_freq;

 	if (policy->min == ~0)
 		return -EINVAL;
 	else
 		return 0;
 }

 int cpufreq_frequency_table_verify(struct cpufreq_policy_data *policy,
 				   struct cpufreq_frequency_table *table)
 {
 	struct cpufreq_frequency_table *pos;
 	unsigned int freq, prev_smaller = 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);

 	cpufreq_for_each_valid_entry(pos, table) {
 		freq = pos->frequency;

 		if ((freq >= policy->min) && (freq <= policy->max)) {
 			found = true;
 			break;
 		}

 		if ((prev_smaller < freq) && (freq <= policy->max))
 			prev_smaller = freq;
 	}

 	if (!found) {
 		policy->max = prev_smaller;
 		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 set
  * policy->freq_table prior to it.
  */
 int cpufreq_generic_frequency_table_verify(struct cpufreq_policy_data *policy)
 {
 	if (!policy->freq_table)
 		return -ENODEV;

 	return cpufreq_frequency_table_verify(policy, policy->freq_table);
 }
 EXPORT_SYMBOL_GPL(cpufreq_generic_frequency_table_verify);

 int cpufreq_table_index_unsorted(struct cpufreq_policy *policy,
 				 unsigned int target_freq,
 				 unsigned int relation)
 {
 	struct cpufreq_frequency_table optimal = {
 		.driver_data = ~0,
 		.frequency = 0,
 	};
 	struct cpufreq_frequency_table suboptimal = {
 		.driver_data = ~0,
 		.frequency = 0,
 	};
 	struct cpufreq_frequency_table *pos;
 	struct cpufreq_frequency_table *table = policy->freq_table;
 	unsigned int freq, diff, i = 0;
 	int index;

 	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:
 	case CPUFREQ_RELATION_C:
 		optimal.frequency = ~0;
 		break;
 	}

 	cpufreq_for_each_valid_entry_idx(pos, table, i) {
 		freq = pos->frequency;

 		if ((freq < policy->min) || (freq > policy->max))
 			continue;
 		if (freq == target_freq) {
 			optimal.driver_data = i;
 			break;
 		}
 		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;
 		case CPUFREQ_RELATION_C:
 			diff = abs(freq - target_freq);
 			if (diff < optimal.frequency ||
 			    (diff == optimal.frequency &&
 			     freq > table[optimal.driver_data].frequency)) {
 				optimal.frequency = diff;
 				optimal.driver_data = i;
 			}
 			break;
 		}
 	}
 	if (optimal.driver_data > i) {
 		if (suboptimal.driver_data > i) {
 			WARN(1, "Invalid frequency table: %u\n", policy->cpu);
 			return 0;
 		}

 		index = suboptimal.driver_data;
 	} else
 		index = optimal.driver_data;

 	pr_debug("target index is %u, freq is:%u kHz\n", index,
 		 table[index].frequency);
 	return index;
 }
 EXPORT_SYMBOL_GPL(cpufreq_table_index_unsorted);

 int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy,
 		unsigned int freq)
 {
 	struct cpufreq_frequency_table *pos, *table = policy->freq_table;
 	int idx;

 	if (unlikely(!table)) {
 		pr_debug("%s: Unable to find frequency table\n", __func__);
 		return -ENOENT;
 	}

 	cpufreq_for_each_valid_entry_idx(pos, table, idx)
 		if (pos->frequency == freq)
 			return idx;

 	return -EINVAL;
 }
 EXPORT_SYMBOL_GPL(cpufreq_frequency_table_get_index);

 /*
  * show_available_freqs - show available frequencies for the specified CPU
  */
 static ssize_t show_available_freqs(struct cpufreq_policy *policy, char *buf,
 				    bool show_boost)
 {
 	ssize_t count = 0;
 	struct cpufreq_frequency_table *pos, *table = policy->freq_table;

 	if (!table)
 		return -ENODEV;

 	cpufreq_for_each_valid_entry(pos, table) {
 		/*
 		 * show_boost = true and driver_data = BOOST freq
 		 * display BOOST freqs
 		 *
 		 * show_boost = false and driver_data = BOOST freq
 		 * show_boost = true and driver_data != BOOST freq
 		 * continue - do not display anything
 		 *
 		 * show_boost = false and driver_data != BOOST freq
 		 * display NON BOOST freqs
 		 */
 		if (show_boost ^ (pos->flags & CPUFREQ_BOOST_FREQ))
 			continue;

 		count += sprintf(&buf[count], "%u ", pos->frequency);
 	}
 	count += sprintf(&buf[count], "\n");

 	return count;

 }

 #define cpufreq_attr_available_freq(_name)	  \
 struct freq_attr cpufreq_freq_attr_##_name##_freqs =     \
 __ATTR_RO(_name##_frequencies)

 /*
  * scaling_available_frequencies_show - show available normal frequencies for
  * the specified CPU
  */
 static ssize_t scaling_available_frequencies_show(struct cpufreq_policy *policy,
 						  char *buf)
 {
 	return show_available_freqs(policy, buf, false);
 }
 cpufreq_attr_available_freq(scaling_available);
 EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_available_freqs);

 /*
  * scaling_boost_frequencies_show - show available boost frequencies for
  * the specified CPU
  */
 static ssize_t scaling_boost_frequencies_show(struct cpufreq_policy *policy,
 					      char *buf)
 {
 	return show_available_freqs(policy, buf, true);
 }
 cpufreq_attr_available_freq(scaling_boost);
 EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_boost_freqs);

 struct freq_attr *cpufreq_generic_attr[] = {
 	&cpufreq_freq_attr_scaling_available_freqs,
 	NULL,
 };
 EXPORT_SYMBOL_GPL(cpufreq_generic_attr);

 static int set_freq_table_sorted(struct cpufreq_policy *policy)
 {
 	struct cpufreq_frequency_table *pos, *table = policy->freq_table;
 	struct cpufreq_frequency_table *prev = NULL;
 	int ascending = 0;

 	policy->freq_table_sorted = CPUFREQ_TABLE_UNSORTED;

 	cpufreq_for_each_valid_entry(pos, table) {
 		if (!prev) {
 			prev = pos;
 			continue;
 		}

 		if (pos->frequency == prev->frequency) {
 			pr_warn("Duplicate freq-table entries: %u\n",
 				pos->frequency);
 			return -EINVAL;
 		}

 		/* Frequency increased from prev to pos */
 		if (pos->frequency > prev->frequency) {
 			/* But frequency was decreasing earlier */
 			if (ascending < 0) {
 				pr_debug("Freq table is unsorted\n");
 				return 0;
 			}

 			ascending++;
 		} else {
 			/* Frequency decreased from prev to pos */

 			/* But frequency was increasing earlier */
 			if (ascending > 0) {
 				pr_debug("Freq table is unsorted\n");
 				return 0;
 			}

 			ascending--;
 		}

 		prev = pos;
 	}

 	if (ascending > 0)
 		policy->freq_table_sorted = CPUFREQ_TABLE_SORTED_ASCENDING;
 	else
 		policy->freq_table_sorted = CPUFREQ_TABLE_SORTED_DESCENDING;

 	pr_debug("Freq table is sorted in %s order\n",
 		 ascending > 0 ? "ascending" : "descending");

 	return 0;
 }

 int cpufreq_table_validate_and_sort(struct cpufreq_policy *policy)
 {
 	int ret;

 	if (!policy->freq_table) {
 		/* Freq table must be passed by drivers with target_index() */
 		if (has_target_index())
 			return -EINVAL;

 		return 0;
 	}

 	ret = cpufreq_frequency_table_cpuinfo(policy, policy->freq_table);
 	if (ret)
 		return ret;

 	return set_freq_table_sorted(policy);
 }

 MODULE_AUTHOR("Dominik Brodowski <linux@brodo.de>");
 MODULE_DESCRIPTION("CPUfreq frequency table helpers");
	// SPDX-License-Identifier: GPL-2.0-only
	/*
	* linux/drivers/cpufreq/freq_table.c
	*
	* Copyright (C) 2002 - 2003 Dominik Brodowski
	*/

	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

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

	/*********************************************************************
	* FREQUENCY TABLE HELPERS *
	*********************************************************************/

	bool policy_has_boost_freq(struct cpufreq_policy *policy)
	{
	struct cpufreq_frequency_table pos, table = policy->freq_table;

	if (!table)
	return false;

	cpufreq_for_each_valid_entry(pos, table)
	if (pos->flags & CPUFREQ_BOOST_FREQ)
	return true;

	return false;
	}
	EXPORT_SYMBOL_GPL(policy_has_boost_freq);

	int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
	struct cpufreq_frequency_table *table)
	{
	struct cpufreq_frequency_table *pos;
	unsigned int min_freq = ~0;
	unsigned int max_freq = 0;
	unsigned int freq;

	cpufreq_for_each_valid_entry(pos, table) {
	freq = pos->frequency;

	if ((!cpufreq_boost_enabled() \|\| !policy->boost_enabled)
	&& (pos->flags & CPUFREQ_BOOST_FREQ))
	continue;

	pr_debug("table entry %u: %u kHz\n", (int)(pos - table), freq);
	if (freq < min_freq)
	min_freq = freq;
	if (freq > max_freq)
	max_freq = freq;
	}

	policy->min = policy->cpuinfo.min_freq = min_freq;
	policy->max = max_freq;
	/*
	* If the driver has set its own cpuinfo.max_freq above max_freq, leave
	* it as is.
	*/
	if (policy->cpuinfo.max_freq < max_freq)
	policy->max = policy->cpuinfo.max_freq = max_freq;

	if (policy->min == ~0)
	return -EINVAL;
	else
	return 0;
	}

	int cpufreq_frequency_table_verify(struct cpufreq_policy_data *policy,
	struct cpufreq_frequency_table *table)
	{
	struct cpufreq_frequency_table *pos;
	unsigned int freq, prev_smaller = 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);

	cpufreq_for_each_valid_entry(pos, table) {
	freq = pos->frequency;

	if ((freq >= policy->min) && (freq <= policy->max)) {
	found = true;
	break;
	}

	if ((prev_smaller < freq) && (freq <= policy->max))
	prev_smaller = freq;
	}

	if (!found) {
	policy->max = prev_smaller;
	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 set
	* policy->freq_table prior to it.
	*/
	int cpufreq_generic_frequency_table_verify(struct cpufreq_policy_data *policy)
	{
	if (!policy->freq_table)
	return -ENODEV;

	return cpufreq_frequency_table_verify(policy, policy->freq_table);
	}
	EXPORT_SYMBOL_GPL(cpufreq_generic_frequency_table_verify);

	int cpufreq_table_index_unsorted(struct cpufreq_policy *policy,
	unsigned int target_freq,
	unsigned int relation)
	{
	struct cpufreq_frequency_table optimal = {
	.driver_data = ~0,
	.frequency = 0,
	};
	struct cpufreq_frequency_table suboptimal = {
	.driver_data = ~0,
	.frequency = 0,
	};
	struct cpufreq_frequency_table *pos;
	struct cpufreq_frequency_table *table = policy->freq_table;
	unsigned int freq, diff, i = 0;
	int index;

	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:
	case CPUFREQ_RELATION_C:
	optimal.frequency = ~0;
	break;
	}

	cpufreq_for_each_valid_entry_idx(pos, table, i) {
	freq = pos->frequency;

	if ((freq < policy->min) \|\| (freq > policy->max))
	continue;
	if (freq == target_freq) {
	optimal.driver_data = i;
	break;
	}
	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;
	case CPUFREQ_RELATION_C:
	diff = abs(freq - target_freq);
	if (diff < optimal.frequency \|\|
	(diff == optimal.frequency &&
	freq > table[optimal.driver_data].frequency)) {
	optimal.frequency = diff;
	optimal.driver_data = i;
	}
	break;
	}
	}
	if (optimal.driver_data > i) {
	if (suboptimal.driver_data > i) {
	WARN(1, "Invalid frequency table: %u\n", policy->cpu);
	return 0;
	}

	index = suboptimal.driver_data;
	} else
	index = optimal.driver_data;

	pr_debug("target index is %u, freq is:%u kHz\n", index,
	table[index].frequency);
	return index;
	}
	EXPORT_SYMBOL_GPL(cpufreq_table_index_unsorted);

	int cpufreq_frequency_table_get_index(struct cpufreq_policy *policy,
	unsigned int freq)
	{
	struct cpufreq_frequency_table pos, table = policy->freq_table;
	int idx;

	if (unlikely(!table)) {
	pr_debug("%s: Unable to find frequency table\n", __func__);
	return -ENOENT;
	}

	cpufreq_for_each_valid_entry_idx(pos, table, idx)
	if (pos->frequency == freq)
	return idx;

	return -EINVAL;
	}
	EXPORT_SYMBOL_GPL(cpufreq_frequency_table_get_index);

	/*
	* show_available_freqs - show available frequencies for the specified CPU
	*/
	static ssize_t show_available_freqs(struct cpufreq_policy policy, char buf,
	bool show_boost)
	{
	ssize_t count = 0;
	struct cpufreq_frequency_table pos, table = policy->freq_table;

	if (!table)
	return -ENODEV;

	cpufreq_for_each_valid_entry(pos, table) {
	/*
	* show_boost = true and driver_data = BOOST freq
	* display BOOST freqs
	*
	* show_boost = false and driver_data = BOOST freq
	* show_boost = true and driver_data != BOOST freq
	* continue - do not display anything
	*
	* show_boost = false and driver_data != BOOST freq
	* display NON BOOST freqs
	*/
	if (show_boost ^ (pos->flags & CPUFREQ_BOOST_FREQ))
	continue;

	count += sprintf(&buf[count], "%u ", pos->frequency);
	}
	count += sprintf(&buf[count], "\n");

	return count;

	}

	#define cpufreq_attr_available_freq(_name) \
	struct freq_attr cpufreq_freq_attr_##_name##_freqs = \
	__ATTR_RO(_name##_frequencies)

	/*
	* scaling_available_frequencies_show - show available normal frequencies for
	* the specified CPU
	*/
	static ssize_t scaling_available_frequencies_show(struct cpufreq_policy *policy,
	char *buf)
	{
	return show_available_freqs(policy, buf, false);
	}
	cpufreq_attr_available_freq(scaling_available);
	EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_available_freqs);

	/*
	* scaling_boost_frequencies_show - show available boost frequencies for
	* the specified CPU
	*/
	static ssize_t scaling_boost_frequencies_show(struct cpufreq_policy *policy,
	char *buf)
	{
	return show_available_freqs(policy, buf, true);
	}
	cpufreq_attr_available_freq(scaling_boost);
	EXPORT_SYMBOL_GPL(cpufreq_freq_attr_scaling_boost_freqs);

	struct freq_attr *cpufreq_generic_attr[] = {
	&cpufreq_freq_attr_scaling_available_freqs,
	NULL,
	};
	EXPORT_SYMBOL_GPL(cpufreq_generic_attr);

	static int set_freq_table_sorted(struct cpufreq_policy *policy)
	{
	struct cpufreq_frequency_table pos, table = policy->freq_table;
	struct cpufreq_frequency_table *prev = NULL;
	int ascending = 0;

	policy->freq_table_sorted = CPUFREQ_TABLE_UNSORTED;

	cpufreq_for_each_valid_entry(pos, table) {
	if (!prev) {
	prev = pos;
	continue;
	}

	if (pos->frequency == prev->frequency) {
	pr_warn("Duplicate freq-table entries: %u\n",
	pos->frequency);
	return -EINVAL;
	}

	/* Frequency increased from prev to pos */
	if (pos->frequency > prev->frequency) {
	/* But frequency was decreasing earlier */
	if (ascending < 0) {
	pr_debug("Freq table is unsorted\n");
	return 0;
	}

	ascending++;
	} else {
	/* Frequency decreased from prev to pos */

	/* But frequency was increasing earlier */
	if (ascending > 0) {
	pr_debug("Freq table is unsorted\n");
	return 0;
	}

	ascending--;
	}

	prev = pos;
	}

	if (ascending > 0)
	policy->freq_table_sorted = CPUFREQ_TABLE_SORTED_ASCENDING;
	else
	policy->freq_table_sorted = CPUFREQ_TABLE_SORTED_DESCENDING;

	pr_debug("Freq table is sorted in %s order\n",
	ascending > 0 ? "ascending" : "descending");

	return 0;
	}

	int cpufreq_table_validate_and_sort(struct cpufreq_policy *policy)
	{
	int ret;

	if (!policy->freq_table) {
	/* Freq table must be passed by drivers with target_index() */
	if (has_target_index())
	return -EINVAL;

	return 0;
	}

	ret = cpufreq_frequency_table_cpuinfo(policy, policy->freq_table);
	if (ret)
	return ret;

	return set_freq_table_sorted(policy);
	}

	MODULE_AUTHOR("Dominik Brodowski <linux@brodo.de>");
	MODULE_DESCRIPTION("CPUfreq frequency table helpers");