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Diffstat (limited to 'tools/power/cpupower/lib/cpufreq.h')
| -rw-r--r-- | tools/power/cpupower/lib/cpufreq.h | 223 |
1 files changed, 223 insertions, 0 deletions
diff --git a/tools/power/cpupower/lib/cpufreq.h b/tools/power/cpupower/lib/cpufreq.h new file mode 100644 index 00000000..3aae8e7a --- /dev/null +++ b/tools/power/cpupower/lib/cpufreq.h @@ -0,0 +1,223 @@ +/* + * cpufreq.h - definitions for libcpufreq + * + * Copyright (C) 2004-2009 Dominik Brodowski <linux@dominikbrodowski.de> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, version 2 of the License. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ + +#ifndef _CPUFREQ_H +#define _CPUFREQ_H 1 + +struct cpufreq_policy { + unsigned long min; + unsigned long max; + char *governor; +}; + +struct cpufreq_available_governors { + char *governor; + struct cpufreq_available_governors *next; + struct cpufreq_available_governors *first; +}; + +struct cpufreq_available_frequencies { + unsigned long frequency; + struct cpufreq_available_frequencies *next; + struct cpufreq_available_frequencies *first; +}; + + +struct cpufreq_affected_cpus { + unsigned int cpu; + struct cpufreq_affected_cpus *next; + struct cpufreq_affected_cpus *first; +}; + +struct cpufreq_stats { + unsigned long frequency; + unsigned long long time_in_state; + struct cpufreq_stats *next; + struct cpufreq_stats *first; +}; + + + +#ifdef __cplusplus +extern "C" { +#endif + +/* + * returns 0 if the specified CPU is present (it doesn't say + * whether it is online!), and an error value if not. + */ + +extern int cpufreq_cpu_exists(unsigned int cpu); + +/* determine current CPU frequency + * - _kernel variant means kernel's opinion of CPU frequency + * - _hardware variant means actual hardware CPU frequency, + * which is only available to root. + * + * returns 0 on failure, else frequency in kHz. + */ + +extern unsigned long cpufreq_get_freq_kernel(unsigned int cpu); + +extern unsigned long cpufreq_get_freq_hardware(unsigned int cpu); + +#define cpufreq_get(cpu) cpufreq_get_freq_kernel(cpu); + + +/* determine CPU transition latency + * + * returns 0 on failure, else transition latency in 10^(-9) s = nanoseconds + */ +extern unsigned long cpufreq_get_transition_latency(unsigned int cpu); + + +/* determine hardware CPU frequency limits + * + * These may be limited further by thermal, energy or other + * considerations by cpufreq policy notifiers in the kernel. + */ + +extern int cpufreq_get_hardware_limits(unsigned int cpu, + unsigned long *min, + unsigned long *max); + + +/* determine CPUfreq driver used + * + * Remember to call cpufreq_put_driver when no longer needed + * to avoid memory leakage, please. + */ + +extern char *cpufreq_get_driver(unsigned int cpu); + +extern void cpufreq_put_driver(char *ptr); + + +/* determine CPUfreq policy currently used + * + * Remember to call cpufreq_put_policy when no longer needed + * to avoid memory leakage, please. + */ + + +extern struct cpufreq_policy *cpufreq_get_policy(unsigned int cpu); + +extern void cpufreq_put_policy(struct cpufreq_policy *policy); + + +/* determine CPUfreq governors currently available + * + * may be modified by modprobe'ing or rmmod'ing other governors. Please + * free allocated memory by calling cpufreq_put_available_governors + * after use. + */ + + +extern struct cpufreq_available_governors +*cpufreq_get_available_governors(unsigned int cpu); + +extern void cpufreq_put_available_governors( + struct cpufreq_available_governors *first); + + +/* determine CPU frequency states available + * + * Only present on _some_ ->target() cpufreq drivers. For information purposes + * only. Please free allocated memory by calling + * cpufreq_put_available_frequencies after use. + */ + +extern struct cpufreq_available_frequencies +*cpufreq_get_available_frequencies(unsigned int cpu); + +extern void cpufreq_put_available_frequencies( + struct cpufreq_available_frequencies *first); + + +/* determine affected CPUs + * + * Remember to call cpufreq_put_affected_cpus when no longer needed + * to avoid memory leakage, please. + */ + +extern struct cpufreq_affected_cpus *cpufreq_get_affected_cpus(unsigned + int cpu); + +extern void cpufreq_put_affected_cpus(struct cpufreq_affected_cpus *first); + + +/* determine related CPUs + * + * Remember to call cpufreq_put_related_cpus when no longer needed + * to avoid memory leakage, please. + */ + +extern struct cpufreq_affected_cpus *cpufreq_get_related_cpus(unsigned + int cpu); + +extern void cpufreq_put_related_cpus(struct cpufreq_affected_cpus *first); + + +/* determine stats for cpufreq subsystem + * + * This is not available in all kernel versions or configurations. + */ + +extern struct cpufreq_stats *cpufreq_get_stats(unsigned int cpu, + unsigned long long *total_time); + +extern void cpufreq_put_stats(struct cpufreq_stats *stats); + +extern unsigned long cpufreq_get_transitions(unsigned int cpu); + + +/* set new cpufreq policy + * + * Tries to set the passed policy as new policy as close as possible, + * but results may differ depending e.g. on governors being available. + */ + +extern int cpufreq_set_policy(unsigned int cpu, struct cpufreq_policy *policy); + + +/* modify a policy by only changing min/max freq or governor + * + * Does not check whether result is what was intended. + */ + +extern int cpufreq_modify_policy_min(unsigned int cpu, unsigned long min_freq); +extern int cpufreq_modify_policy_max(unsigned int cpu, unsigned long max_freq); +extern int cpufreq_modify_policy_governor(unsigned int cpu, char *governor); + + +/* set a specific frequency + * + * Does only work if userspace governor can be used and no external + * interference (other calls to this function or to set/modify_policy) + * occurs. Also does not work on ->range() cpufreq drivers. + */ + +extern int cpufreq_set_frequency(unsigned int cpu, + unsigned long target_frequency); + +#ifdef __cplusplus +} +#endif + +#endif /* _CPUFREQ_H */ |