linux_dsm_epyc7002/drivers/cpufreq/freq_table.c
Viresh Kumar 184345129c cpufreq: define generic .attr, .exit() and .verify() routines
Most of the CPUFreq drivers do similar things in .exit() and .verify() routines
and .attr. So its better if we have generic routines for them which can be used
by cpufreq drivers then.

This patch introduces generic .attr, .exit() and .verify() cpufreq drivers.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-10-16 00:50:23 +02:00

271 lines
7.1 KiB
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.
*
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/cpufreq.h>
#include <linux/module.h>
/*********************************************************************
* 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) {
pr_debug("table entry %u is invalid, skipping\n", i);
continue;
}
pr_debug("table entry %u: %u kHz, %u driver_data\n",
i, freq, table[i].driver_data);
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, freq, i = 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);
for (; freq = table[i].frequency, freq != CPUFREQ_TABLE_END; i++) {
if (freq == CPUFREQ_ENTRY_INVALID)
continue;
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 call
* cpufreq_frequency_table_get_attr() prior to it.
*/
int cpufreq_generic_frequency_table_verify(struct cpufreq_policy *policy)
{
struct cpufreq_frequency_table *table =
cpufreq_frequency_get_table(policy->cpu);
if (!table)
return -ENODEV;
return cpufreq_frequency_table_verify(policy, table);
}
EXPORT_SYMBOL_GPL(cpufreq_generic_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 = {
.driver_data = ~0,
.frequency = 0,
};
struct cpufreq_frequency_table suboptimal = {
.driver_data = ~0,
.frequency = 0,
};
unsigned int i;
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:
optimal.frequency = ~0;
break;
}
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.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;
}
}
if (optimal.driver_data > i) {
if (suboptimal.driver_data > i)
return -EINVAL;
*index = suboptimal.driver_data;
} else
*index = optimal.driver_data;
pr_debug("target is %u (%u kHz, %u)\n", *index, table[*index].frequency,
table[*index].driver_data);
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);
struct freq_attr *cpufreq_generic_attr[] = {
&cpufreq_freq_attr_scaling_available_freqs,
NULL,
};
EXPORT_SYMBOL_GPL(cpufreq_generic_attr);
/*
* 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)
{
pr_debug("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)
{
pr_debug("clearing show_table for cpu %u\n", cpu);
per_cpu(cpufreq_show_table, cpu) = NULL;
}
EXPORT_SYMBOL_GPL(cpufreq_frequency_table_put_attr);
int cpufreq_table_validate_and_show(struct cpufreq_policy *policy,
struct cpufreq_frequency_table *table)
{
int ret = cpufreq_frequency_table_cpuinfo(policy, table);
if (!ret)
cpufreq_frequency_table_get_attr(table, policy->cpu);
return ret;
}
EXPORT_SYMBOL_GPL(cpufreq_table_validate_and_show);
void cpufreq_frequency_table_update_policy_cpu(struct cpufreq_policy *policy)
{
pr_debug("Updating show_table for new_cpu %u from last_cpu %u\n",
policy->cpu, policy->last_cpu);
per_cpu(cpufreq_show_table, policy->cpu) = per_cpu(cpufreq_show_table,
policy->last_cpu);
per_cpu(cpufreq_show_table, policy->last_cpu) = NULL;
}
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");