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-rw-r--r--drivers/cpufreq/cpufreq_governor.h176
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diff --git a/drivers/cpufreq/cpufreq_governor.h b/drivers/cpufreq/cpufreq_governor.h
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+/*
+ * drivers/cpufreq/cpufreq_governor.h
+ *
+ * Header file for CPUFreq governors common code
+ *
+ * Copyright (C) 2001 Russell King
+ * (C) 2003 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>.
+ * (C) 2003 Jun Nakajima <jun.nakajima@intel.com>
+ * (C) 2009 Alexander Clouter <alex@digriz.org.uk>
+ * (c) 2012 Viresh Kumar <viresh.kumar@linaro.org>
+ *
+ * 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 _CPUFREQ_GOVERNER_H
+#define _CPUFREQ_GOVERNER_H
+
+#include <linux/cpufreq.h>
+#include <linux/kobject.h>
+#include <linux/mutex.h>
+#include <linux/workqueue.h>
+#include <linux/sysfs.h>
+
+/*
+ * The polling frequency depends on the capability of the processor. Default
+ * polling frequency is 1000 times the transition latency of the processor. The
+ * governor will work on any processor with transition latency <= 10mS, using
+ * appropriate sampling rate.
+ *
+ * For CPUs with transition latency > 10mS (mostly drivers with CPUFREQ_ETERNAL)
+ * this governor will not work. All times here are in uS.
+ */
+#define MIN_SAMPLING_RATE_RATIO (2)
+#define LATENCY_MULTIPLIER (1000)
+#define MIN_LATENCY_MULTIPLIER (100)
+#define TRANSITION_LATENCY_LIMIT (10 * 1000 * 1000)
+
+/* Ondemand Sampling types */
+enum {OD_NORMAL_SAMPLE, OD_SUB_SAMPLE};
+
+/* Macro creating sysfs show routines */
+#define show_one(_gov, file_name, object) \
+static ssize_t show_##file_name \
+(struct kobject *kobj, struct attribute *attr, char *buf) \
+{ \
+ return sprintf(buf, "%u\n", _gov##_tuners.object); \
+}
+
+#define define_get_cpu_dbs_routines(_dbs_info) \
+static struct cpu_dbs_common_info *get_cpu_cdbs(int cpu) \
+{ \
+ return &per_cpu(_dbs_info, cpu).cdbs; \
+} \
+ \
+static void *get_cpu_dbs_info_s(int cpu) \
+{ \
+ return &per_cpu(_dbs_info, cpu); \
+}
+
+/*
+ * Abbreviations:
+ * dbs: used as a shortform for demand based switching It helps to keep variable
+ * names smaller, simpler
+ * cdbs: common dbs
+ * on_*: On-demand governor
+ * cs_*: Conservative governor
+ */
+
+/* Per cpu structures */
+struct cpu_dbs_common_info {
+ int cpu;
+ u64 prev_cpu_idle;
+ u64 prev_cpu_wall;
+ u64 prev_cpu_nice;
+ struct cpufreq_policy *cur_policy;
+ struct delayed_work work;
+ /*
+ * percpu mutex that serializes governor limit change with gov_dbs_timer
+ * invocation. We do not want gov_dbs_timer to run when user is changing
+ * the governor or limits.
+ */
+ struct mutex timer_mutex;
+};
+
+struct od_cpu_dbs_info_s {
+ struct cpu_dbs_common_info cdbs;
+ u64 prev_cpu_iowait;
+ struct cpufreq_frequency_table *freq_table;
+ unsigned int freq_lo;
+ unsigned int freq_lo_jiffies;
+ unsigned int freq_hi_jiffies;
+ unsigned int rate_mult;
+ unsigned int sample_type:1;
+};
+
+struct cs_cpu_dbs_info_s {
+ struct cpu_dbs_common_info cdbs;
+ unsigned int down_skip;
+ unsigned int requested_freq;
+ unsigned int enable:1;
+};
+
+/* Governers sysfs tunables */
+struct od_dbs_tuners {
+ unsigned int ignore_nice;
+ unsigned int sampling_rate;
+ unsigned int sampling_down_factor;
+ unsigned int up_threshold;
+ unsigned int down_differential;
+ unsigned int powersave_bias;
+ unsigned int io_is_busy;
+};
+
+struct cs_dbs_tuners {
+ unsigned int ignore_nice;
+ unsigned int sampling_rate;
+ unsigned int sampling_down_factor;
+ unsigned int up_threshold;
+ unsigned int down_threshold;
+ unsigned int freq_step;
+};
+
+/* Per Governer data */
+struct dbs_data {
+ /* Common across governors */
+ #define GOV_ONDEMAND 0
+ #define GOV_CONSERVATIVE 1
+ int governor;
+ unsigned int min_sampling_rate;
+ unsigned int enable; /* number of CPUs using this policy */
+ struct attribute_group *attr_group;
+ void *tuners;
+
+ /* dbs_mutex protects dbs_enable in governor start/stop */
+ struct mutex mutex;
+
+ struct cpu_dbs_common_info *(*get_cpu_cdbs)(int cpu);
+ void *(*get_cpu_dbs_info_s)(int cpu);
+ void (*gov_dbs_timer)(struct work_struct *work);
+ void (*gov_check_cpu)(int cpu, unsigned int load);
+
+ /* Governor specific ops, see below */
+ void *gov_ops;
+};
+
+/* Governor specific ops, will be passed to dbs_data->gov_ops */
+struct od_ops {
+ int (*io_busy)(void);
+ void (*powersave_bias_init_cpu)(int cpu);
+ unsigned int (*powersave_bias_target)(struct cpufreq_policy *policy,
+ unsigned int freq_next, unsigned int relation);
+ void (*freq_increase)(struct cpufreq_policy *p, unsigned int freq);
+};
+
+struct cs_ops {
+ struct notifier_block *notifier_block;
+};
+
+static inline int delay_for_sampling_rate(unsigned int sampling_rate)
+{
+ int delay = usecs_to_jiffies(sampling_rate);
+
+ /* We want all CPUs to do sampling nearly on same jiffy */
+ if (num_online_cpus() > 1)
+ delay -= jiffies % delay;
+
+ return delay;
+}
+
+u64 get_cpu_idle_time(unsigned int cpu, u64 *wall);
+void dbs_check_cpu(struct dbs_data *dbs_data, int cpu);
+int cpufreq_governor_dbs(struct dbs_data *dbs_data,
+ struct cpufreq_policy *policy, unsigned int event);
+#endif /* _CPUFREQ_GOVERNER_H */