/* * 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. * */ #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; 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; 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, .frequency = 0, }; struct cpufreq_frequency_table suboptimal = { .index = ~0, .frequency = 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: suboptimal.frequency = ~0; break; case CPUFREQ_RELATION_L: optimal.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 DEFINE_PER_CPU(struct cpufreq_frequency_table *, 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(show_table, cpu)) return -ENODEV; table = per_cpu(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); /* * 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); per_cpu(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); per_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 per_cpu(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");