// 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 <[email protected]>");
MODULE_DESCRIPTION("CPUfreq frequency table helpers");
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