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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/linux/cpufreq.h
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'include/linux/cpufreq.h')
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diff --git a/include/linux/cpufreq.h b/include/linux/cpufreq.h
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+++ b/include/linux/cpufreq.h
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+/*
+ * linux/include/linux/cpufreq.h
+ *
+ * Copyright (C) 2001 Russell King
+ * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de>
+ *
+ *
+ * $Id: cpufreq.h,v 1.36 2003/01/20 17:31:48 db Exp $
+ *
+ * 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.
+ */
+#ifndef _LINUX_CPUFREQ_H
+#define _LINUX_CPUFREQ_H
+
+#include <linux/config.h>
+#include <linux/notifier.h>
+#include <linux/threads.h>
+#include <linux/device.h>
+#include <linux/kobject.h>
+#include <linux/sysfs.h>
+#include <linux/completion.h>
+#include <linux/workqueue.h>
+#include <linux/cpumask.h>
+
+#define CPUFREQ_NAME_LEN 16
+
+
+/*********************************************************************
+ * CPUFREQ NOTIFIER INTERFACE *
+ *********************************************************************/
+
+int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list);
+int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list);
+
+#define CPUFREQ_TRANSITION_NOTIFIER (0)
+#define CPUFREQ_POLICY_NOTIFIER (1)
+
+
+/* if (cpufreq_driver->target) exists, the ->governor decides what frequency
+ * within the limits is used. If (cpufreq_driver->setpolicy> exists, these
+ * two generic policies are available:
+ */
+
+#define CPUFREQ_POLICY_POWERSAVE (1)
+#define CPUFREQ_POLICY_PERFORMANCE (2)
+
+/* Frequency values here are CPU kHz so that hardware which doesn't run
+ * with some frequencies can complain without having to guess what per
+ * cent / per mille means.
+ * Maximum transition latency is in microseconds - if it's unknown,
+ * CPUFREQ_ETERNAL shall be used.
+ */
+
+struct cpufreq_governor;
+
+#define CPUFREQ_ETERNAL (-1)
+struct cpufreq_cpuinfo {
+ unsigned int max_freq;
+ unsigned int min_freq;
+ unsigned int transition_latency; /* in 10^(-9) s = nanoseconds */
+};
+
+struct cpufreq_real_policy {
+ unsigned int min; /* in kHz */
+ unsigned int max; /* in kHz */
+ unsigned int policy; /* see above */
+ struct cpufreq_governor *governor; /* see below */
+};
+
+struct cpufreq_policy {
+ cpumask_t cpus; /* affected CPUs */
+ unsigned int cpu; /* cpu nr of registered CPU */
+ struct cpufreq_cpuinfo cpuinfo;/* see above */
+
+ unsigned int min; /* in kHz */
+ unsigned int max; /* in kHz */
+ unsigned int cur; /* in kHz, only needed if cpufreq
+ * governors are used */
+ unsigned int policy; /* see above */
+ struct cpufreq_governor *governor; /* see below */
+
+ struct semaphore lock; /* CPU ->setpolicy or ->target may
+ only be called once a time */
+
+ struct work_struct update; /* if update_policy() needs to be
+ * called, but you're in IRQ context */
+
+ struct cpufreq_real_policy user_policy;
+
+ struct kobject kobj;
+ struct completion kobj_unregister;
+};
+
+#define CPUFREQ_ADJUST (0)
+#define CPUFREQ_INCOMPATIBLE (1)
+#define CPUFREQ_NOTIFY (2)
+
+
+/******************** cpufreq transition notifiers *******************/
+
+#define CPUFREQ_PRECHANGE (0)
+#define CPUFREQ_POSTCHANGE (1)
+#define CPUFREQ_RESUMECHANGE (8)
+
+struct cpufreq_freqs {
+ unsigned int cpu; /* cpu nr */
+ unsigned int old;
+ unsigned int new;
+ u8 flags; /* flags of cpufreq_driver, see below. */
+};
+
+
+/**
+ * cpufreq_scale - "old * mult / div" calculation for large values (32-bit-arch safe)
+ * @old: old value
+ * @div: divisor
+ * @mult: multiplier
+ *
+ *
+ * new = old * mult / div
+ */
+static inline unsigned long cpufreq_scale(unsigned long old, u_int div, u_int mult)
+{
+#if BITS_PER_LONG == 32
+
+ u64 result = ((u64) old) * ((u64) mult);
+ do_div(result, div);
+ return (unsigned long) result;
+
+#elif BITS_PER_LONG == 64
+
+ unsigned long result = old * ((u64) mult);
+ result /= div;
+ return result;
+
+#endif
+};
+
+/*********************************************************************
+ * CPUFREQ GOVERNORS *
+ *********************************************************************/
+
+#define CPUFREQ_GOV_START 1
+#define CPUFREQ_GOV_STOP 2
+#define CPUFREQ_GOV_LIMITS 3
+
+struct cpufreq_governor {
+ char name[CPUFREQ_NAME_LEN];
+ int (*governor) (struct cpufreq_policy *policy,
+ unsigned int event);
+ struct list_head governor_list;
+ struct module *owner;
+};
+
+/* pass a target to the cpufreq driver
+ */
+extern int cpufreq_driver_target(struct cpufreq_policy *policy,
+ unsigned int target_freq,
+ unsigned int relation);
+extern int __cpufreq_driver_target(struct cpufreq_policy *policy,
+ unsigned int target_freq,
+ unsigned int relation);
+
+
+/* pass an event to the cpufreq governor */
+int cpufreq_governor(unsigned int cpu, unsigned int event);
+
+int cpufreq_register_governor(struct cpufreq_governor *governor);
+void cpufreq_unregister_governor(struct cpufreq_governor *governor);
+
+
+/*********************************************************************
+ * CPUFREQ DRIVER INTERFACE *
+ *********************************************************************/
+
+#define CPUFREQ_RELATION_L 0 /* lowest frequency at or above target */
+#define CPUFREQ_RELATION_H 1 /* highest frequency below or at target */
+
+struct freq_attr;
+
+struct cpufreq_driver {
+ struct module *owner;
+ char name[CPUFREQ_NAME_LEN];
+ u8 flags;
+
+ /* needed by all drivers */
+ int (*init) (struct cpufreq_policy *policy);
+ int (*verify) (struct cpufreq_policy *policy);
+
+ /* define one out of two */
+ int (*setpolicy) (struct cpufreq_policy *policy);
+ int (*target) (struct cpufreq_policy *policy,
+ unsigned int target_freq,
+ unsigned int relation);
+
+ /* should be defined, if possible */
+ unsigned int (*get) (unsigned int cpu);
+
+ /* optional */
+ int (*exit) (struct cpufreq_policy *policy);
+ int (*resume) (struct cpufreq_policy *policy);
+ struct freq_attr **attr;
+};
+
+/* flags */
+
+#define CPUFREQ_STICKY 0x01 /* the driver isn't removed even if
+ * all ->init() calls failed */
+#define CPUFREQ_CONST_LOOPS 0x02 /* loops_per_jiffy or other kernel
+ * "constants" aren't affected by
+ * frequency transitions */
+
+
+int cpufreq_register_driver(struct cpufreq_driver *driver_data);
+int cpufreq_unregister_driver(struct cpufreq_driver *driver_data);
+
+
+void cpufreq_notify_transition(struct cpufreq_freqs *freqs, unsigned int state);
+
+
+static inline void cpufreq_verify_within_limits(struct cpufreq_policy *policy, unsigned int min, unsigned int max)
+{
+ if (policy->min < min)
+ policy->min = min;
+ if (policy->max < min)
+ policy->max = min;
+ if (policy->min > max)
+ policy->min = max;
+ if (policy->max > max)
+ policy->max = max;
+ if (policy->min > policy->max)
+ policy->min = policy->max;
+ return;
+}
+
+struct freq_attr {
+ struct attribute attr;
+ ssize_t (*show)(struct cpufreq_policy *, char *);
+ ssize_t (*store)(struct cpufreq_policy *, const char *, size_t count);
+};
+
+
+/*********************************************************************
+ * CPUFREQ 2.6. INTERFACE *
+ *********************************************************************/
+int cpufreq_set_policy(struct cpufreq_policy *policy);
+int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu);
+int cpufreq_update_policy(unsigned int cpu);
+
+/* query the current CPU frequency (in kHz). If zero, cpufreq couldn't detect it */
+unsigned int cpufreq_get(unsigned int cpu);
+
+
+/*********************************************************************
+ * CPUFREQ DEFAULT GOVERNOR *
+ *********************************************************************/
+
+
+#ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_PERFORMANCE
+extern struct cpufreq_governor cpufreq_gov_performance;
+#define CPUFREQ_DEFAULT_GOVERNOR &cpufreq_gov_performance
+#elif defined(CONFIG_CPU_FREQ_DEFAULT_GOV_USERSPACE)
+extern struct cpufreq_governor cpufreq_gov_userspace;
+#define CPUFREQ_DEFAULT_GOVERNOR &cpufreq_gov_userspace
+#endif
+
+
+/*********************************************************************
+ * FREQUENCY TABLE HELPERS *
+ *********************************************************************/
+
+#define CPUFREQ_ENTRY_INVALID ~0
+#define CPUFREQ_TABLE_END ~1
+
+struct cpufreq_frequency_table {
+ unsigned int index; /* any */
+ unsigned int frequency; /* kHz - doesn't need to be in ascending
+ * order */
+};
+
+int cpufreq_frequency_table_cpuinfo(struct cpufreq_policy *policy,
+ struct cpufreq_frequency_table *table);
+
+int cpufreq_frequency_table_verify(struct cpufreq_policy *policy,
+ struct cpufreq_frequency_table *table);
+
+int cpufreq_frequency_table_target(struct cpufreq_policy *policy,
+ struct cpufreq_frequency_table *table,
+ unsigned int target_freq,
+ unsigned int relation,
+ unsigned int *index);
+
+/* the following 3 funtions are for cpufreq core use only */
+struct cpufreq_frequency_table *cpufreq_frequency_get_table(unsigned int cpu);
+struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu);
+void cpufreq_cpu_put (struct cpufreq_policy *data);
+
+/* the following are really really optional */
+extern struct freq_attr cpufreq_freq_attr_scaling_available_freqs;
+
+void cpufreq_frequency_table_get_attr(struct cpufreq_frequency_table *table,
+ unsigned int cpu);
+
+void cpufreq_frequency_table_put_attr(unsigned int cpu);
+
+
+/*********************************************************************
+ * UNIFIED DEBUG HELPERS *
+ *********************************************************************/
+
+#define CPUFREQ_DEBUG_CORE 1
+#define CPUFREQ_DEBUG_DRIVER 2
+#define CPUFREQ_DEBUG_GOVERNOR 4
+
+#ifdef CONFIG_CPU_FREQ_DEBUG
+
+extern void cpufreq_debug_printk(unsigned int type, const char *prefix,
+ const char *fmt, ...);
+
+#else
+
+#define cpufreq_debug_printk(msg...) do { } while(0)
+
+#endif /* CONFIG_CPU_FREQ_DEBUG */
+
+#endif /* _LINUX_CPUFREQ_H */