diff options
Diffstat (limited to 'drivers/cpufreq/freq_table.c')
-rw-r--r-- | drivers/cpufreq/freq_table.c | 374 |
1 files changed, 374 insertions, 0 deletions
diff --git a/drivers/cpufreq/freq_table.c b/drivers/cpufreq/freq_table.c new file mode 100644 index 0000000000..c4d4643b6c --- /dev/null +++ b/drivers/cpufreq/freq_table.c @@ -0,0 +1,374 @@ +// 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() + && (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, next_larger = ~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 ((next_larger > freq) && (freq > policy->max)) + next_larger = freq; + } + + if (!found) { + policy->max = next_larger; + 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: %d\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], "%d ", 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"); |