diff options
Diffstat (limited to 'drivers/cpufreq/freq_table.c')
| -rw-r--r-- | drivers/cpufreq/freq_table.c | 225 |
1 files changed, 225 insertions, 0 deletions
diff --git a/drivers/cpufreq/freq_table.c b/drivers/cpufreq/freq_table.c new file mode 100644 index 00000000000..ba460bdea60 --- /dev/null +++ b/drivers/cpufreq/freq_table.c @@ -0,0 +1,225 @@ +/* + * 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 = 0; + + 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 = 0; + 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, }; + struct cpufreq_frequency_table suboptimal = { .index = ~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: + optimal.frequency = 0; + suboptimal.frequency = ~0; + break; + case CPUFREQ_RELATION_L: + optimal.frequency = ~0; + suboptimal.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, .owner=THIS_MODULE }, + .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"); |