zte's code,first commit
Change-Id: I9a04da59e459a9bc0d67f101f700d9d7dc8d681b
diff --git a/ap/os/linux/linux-3.4.x/drivers/cpufreq/cpufreq_conservative.c b/ap/os/linux/linux-3.4.x/drivers/cpufreq/cpufreq_conservative.c
new file mode 100644
index 0000000..1b98434
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/drivers/cpufreq/cpufreq_conservative.c
@@ -0,0 +1,628 @@
+/*
+ * drivers/cpufreq/cpufreq_conservative.c
+ *
+ * Copyright (C) 2001 Russell King
+ * (C) 2003 Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>.
+ * Jun Nakajima <jun.nakajima@intel.com>
+ * (C) 2009 Alexander Clouter <alex@digriz.org.uk>
+ *
+ * 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>
+#include <linux/cpu.h>
+#include <linux/jiffies.h>
+#include <linux/kernel_stat.h>
+#include <linux/mutex.h>
+#include <linux/hrtimer.h>
+#include <linux/tick.h>
+#include <linux/ktime.h>
+#include <linux/sched.h>
+
+/*
+ * dbs is used in this file as a shortform for demandbased switching
+ * It helps to keep variable names smaller, simpler
+ */
+
+#define DEF_FREQUENCY_UP_THRESHOLD (80)
+#define DEF_FREQUENCY_DOWN_THRESHOLD (20)
+
+/*
+ * The polling frequency of this governor 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)
+
+static unsigned int min_sampling_rate;
+
+#define LATENCY_MULTIPLIER (1000)
+#define MIN_LATENCY_MULTIPLIER (100)
+#define DEF_SAMPLING_DOWN_FACTOR (1)
+#define MAX_SAMPLING_DOWN_FACTOR (10)
+#define TRANSITION_LATENCY_LIMIT (10 * 1000 * 1000)
+
+static void do_dbs_timer(struct work_struct *work);
+
+struct cpu_dbs_info_s {
+ cputime64_t prev_cpu_idle;
+ cputime64_t prev_cpu_wall;
+ cputime64_t prev_cpu_nice;
+ struct cpufreq_policy *cur_policy;
+ struct delayed_work work;
+ unsigned int down_skip;
+ unsigned int requested_freq;
+ int cpu;
+ unsigned int enable:1;
+ /*
+ * percpu mutex that serializes governor limit change with
+ * do_dbs_timer invocation. We do not want do_dbs_timer to run
+ * when user is changing the governor or limits.
+ */
+ struct mutex timer_mutex;
+};
+static DEFINE_PER_CPU(struct cpu_dbs_info_s, cs_cpu_dbs_info);
+
+static unsigned int dbs_enable; /* number of CPUs using this policy */
+
+/*
+ * dbs_mutex protects dbs_enable in governor start/stop.
+ */
+static DEFINE_MUTEX(dbs_mutex);
+
+static struct dbs_tuners {
+ unsigned int sampling_rate;
+ unsigned int sampling_down_factor;
+ unsigned int up_threshold;
+ unsigned int down_threshold;
+ unsigned int ignore_nice;
+ unsigned int freq_step;
+} dbs_tuners_ins = {
+ .up_threshold = DEF_FREQUENCY_UP_THRESHOLD,
+ .down_threshold = DEF_FREQUENCY_DOWN_THRESHOLD,
+ .sampling_down_factor = DEF_SAMPLING_DOWN_FACTOR,
+ .ignore_nice = 0,
+ .freq_step = 5,
+};
+
+static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall)
+{
+ u64 idle_time;
+ u64 cur_wall_time;
+ u64 busy_time;
+
+ cur_wall_time = jiffies64_to_cputime64(get_jiffies_64());
+
+ busy_time = kcpustat_cpu(cpu).cpustat[CPUTIME_USER];
+ busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SYSTEM];
+ busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_IRQ];
+ busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SOFTIRQ];
+ busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_STEAL];
+ busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_NICE];
+
+ idle_time = cur_wall_time - busy_time;
+ if (wall)
+ *wall = jiffies_to_usecs(cur_wall_time);
+
+ return jiffies_to_usecs(idle_time);
+}
+
+static inline cputime64_t get_cpu_idle_time(unsigned int cpu, cputime64_t *wall)
+{
+ u64 idle_time = get_cpu_idle_time_us(cpu, NULL);
+
+ if (idle_time == -1ULL)
+ return get_cpu_idle_time_jiffy(cpu, wall);
+ else
+ idle_time += get_cpu_iowait_time_us(cpu, wall);
+
+ return idle_time;
+}
+
+/* keep track of frequency transitions */
+static int
+dbs_cpufreq_notifier(struct notifier_block *nb, unsigned long val,
+ void *data)
+{
+ struct cpufreq_freqs *freq = data;
+ struct cpu_dbs_info_s *this_dbs_info = &per_cpu(cs_cpu_dbs_info,
+ freq->cpu);
+
+ struct cpufreq_policy *policy;
+
+ if (!this_dbs_info->enable)
+ return 0;
+
+ policy = this_dbs_info->cur_policy;
+
+ /*
+ * we only care if our internally tracked freq moves outside
+ * the 'valid' ranges of freqency available to us otherwise
+ * we do not change it
+ */
+ if (this_dbs_info->requested_freq > policy->max
+ || this_dbs_info->requested_freq < policy->min)
+ this_dbs_info->requested_freq = freq->new;
+
+ return 0;
+}
+
+static struct notifier_block dbs_cpufreq_notifier_block = {
+ .notifier_call = dbs_cpufreq_notifier
+};
+
+/************************** sysfs interface ************************/
+static ssize_t show_sampling_rate_min(struct kobject *kobj,
+ struct attribute *attr, char *buf)
+{
+ return sprintf(buf, "%u\n", min_sampling_rate);
+}
+
+define_one_global_ro(sampling_rate_min);
+
+/* cpufreq_conservative Governor Tunables */
+#define show_one(file_name, object) \
+static ssize_t show_##file_name \
+(struct kobject *kobj, struct attribute *attr, char *buf) \
+{ \
+ return sprintf(buf, "%u\n", dbs_tuners_ins.object); \
+}
+show_one(sampling_rate, sampling_rate);
+show_one(sampling_down_factor, sampling_down_factor);
+show_one(up_threshold, up_threshold);
+show_one(down_threshold, down_threshold);
+show_one(ignore_nice_load, ignore_nice);
+show_one(freq_step, freq_step);
+
+static ssize_t store_sampling_down_factor(struct kobject *a,
+ struct attribute *b,
+ const char *buf, size_t count)
+{
+ unsigned int input;
+ int ret;
+ ret = sscanf(buf, "%u", &input);
+
+ if (ret != 1 || input > MAX_SAMPLING_DOWN_FACTOR || input < 1)
+ return -EINVAL;
+
+ dbs_tuners_ins.sampling_down_factor = input;
+ return count;
+}
+
+static ssize_t store_sampling_rate(struct kobject *a, struct attribute *b,
+ const char *buf, size_t count)
+{
+ unsigned int input;
+ int ret;
+ ret = sscanf(buf, "%u", &input);
+
+ if (ret != 1)
+ return -EINVAL;
+
+ dbs_tuners_ins.sampling_rate = max(input, min_sampling_rate);
+ return count;
+}
+
+static ssize_t store_up_threshold(struct kobject *a, struct attribute *b,
+ const char *buf, size_t count)
+{
+ unsigned int input;
+ int ret;
+ ret = sscanf(buf, "%u", &input);
+
+ if (ret != 1 || input > 100 ||
+ input <= dbs_tuners_ins.down_threshold)
+ return -EINVAL;
+
+ dbs_tuners_ins.up_threshold = input;
+ return count;
+}
+
+static ssize_t store_down_threshold(struct kobject *a, struct attribute *b,
+ const char *buf, size_t count)
+{
+ unsigned int input;
+ int ret;
+ ret = sscanf(buf, "%u", &input);
+
+ /* cannot be lower than 11 otherwise freq will not fall */
+ if (ret != 1 || input < 11 || input > 100 ||
+ input >= dbs_tuners_ins.up_threshold)
+ return -EINVAL;
+
+ dbs_tuners_ins.down_threshold = input;
+ return count;
+}
+
+static ssize_t store_ignore_nice_load(struct kobject *a, struct attribute *b,
+ const char *buf, size_t count)
+{
+ unsigned int input;
+ int ret;
+
+ unsigned int j;
+
+ ret = sscanf(buf, "%u", &input);
+ if (ret != 1)
+ return -EINVAL;
+
+ if (input > 1)
+ input = 1;
+
+ if (input == dbs_tuners_ins.ignore_nice) /* nothing to do */
+ return count;
+
+ dbs_tuners_ins.ignore_nice = input;
+
+ /* we need to re-evaluate prev_cpu_idle */
+ for_each_online_cpu(j) {
+ struct cpu_dbs_info_s *dbs_info;
+ dbs_info = &per_cpu(cs_cpu_dbs_info, j);
+ dbs_info->prev_cpu_idle = get_cpu_idle_time(j,
+ &dbs_info->prev_cpu_wall);
+ if (dbs_tuners_ins.ignore_nice)
+ dbs_info->prev_cpu_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE];
+ }
+ return count;
+}
+
+static ssize_t store_freq_step(struct kobject *a, struct attribute *b,
+ const char *buf, size_t count)
+{
+ unsigned int input;
+ int ret;
+ ret = sscanf(buf, "%u", &input);
+
+ if (ret != 1)
+ return -EINVAL;
+
+ if (input > 100)
+ input = 100;
+
+ /* no need to test here if freq_step is zero as the user might actually
+ * want this, they would be crazy though :) */
+ dbs_tuners_ins.freq_step = input;
+ return count;
+}
+
+define_one_global_rw(sampling_rate);
+define_one_global_rw(sampling_down_factor);
+define_one_global_rw(up_threshold);
+define_one_global_rw(down_threshold);
+define_one_global_rw(ignore_nice_load);
+define_one_global_rw(freq_step);
+
+static struct attribute *dbs_attributes[] = {
+ &sampling_rate_min.attr,
+ &sampling_rate.attr,
+ &sampling_down_factor.attr,
+ &up_threshold.attr,
+ &down_threshold.attr,
+ &ignore_nice_load.attr,
+ &freq_step.attr,
+ NULL
+};
+
+static struct attribute_group dbs_attr_group = {
+ .attrs = dbs_attributes,
+ .name = "conservative",
+};
+
+/************************** sysfs end ************************/
+
+static void dbs_check_cpu(struct cpu_dbs_info_s *this_dbs_info)
+{
+ unsigned int load = 0;
+ unsigned int max_load = 0;
+ unsigned int freq_target;
+
+ struct cpufreq_policy *policy;
+ unsigned int j;
+
+ policy = this_dbs_info->cur_policy;
+
+ /*
+ * Every sampling_rate, we check, if current idle time is less
+ * than 20% (default), then we try to increase frequency
+ * Every sampling_rate*sampling_down_factor, we check, if current
+ * idle time is more than 80%, then we try to decrease frequency
+ *
+ * Any frequency increase takes it to the maximum frequency.
+ * Frequency reduction happens at minimum steps of
+ * 5% (default) of maximum frequency
+ */
+
+ /* Get Absolute Load */
+ for_each_cpu(j, policy->cpus) {
+ struct cpu_dbs_info_s *j_dbs_info;
+ cputime64_t cur_wall_time, cur_idle_time;
+ unsigned int idle_time, wall_time;
+ #ifdef CONFIG_KLOCWORK
+ cur_wall_time=0;
+ #endif
+
+ j_dbs_info = &per_cpu(cs_cpu_dbs_info, j);
+
+ cur_idle_time = get_cpu_idle_time(j, &cur_wall_time);
+
+ wall_time = (unsigned int)
+ (cur_wall_time - j_dbs_info->prev_cpu_wall);
+ j_dbs_info->prev_cpu_wall = cur_wall_time;
+
+ idle_time = (unsigned int)
+ (cur_idle_time - j_dbs_info->prev_cpu_idle);
+ j_dbs_info->prev_cpu_idle = cur_idle_time;
+
+ if (dbs_tuners_ins.ignore_nice) {
+ u64 cur_nice;
+ unsigned long cur_nice_jiffies;
+
+ cur_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE] -
+ j_dbs_info->prev_cpu_nice;
+ /*
+ * Assumption: nice time between sampling periods will
+ * be less than 2^32 jiffies for 32 bit sys
+ */
+ cur_nice_jiffies = (unsigned long)
+ cputime64_to_jiffies64(cur_nice);
+
+ j_dbs_info->prev_cpu_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE];
+ idle_time += jiffies_to_usecs(cur_nice_jiffies);
+ }
+
+ if (unlikely(!wall_time || wall_time < idle_time))
+ continue;
+
+ load = 100 * (wall_time - idle_time) / wall_time;
+
+ if (load > max_load)
+ max_load = load;
+ }
+
+ /*
+ * break out if we 'cannot' reduce the speed as the user might
+ * want freq_step to be zero
+ */
+ if (dbs_tuners_ins.freq_step == 0)
+ return;
+
+ /* Check for frequency increase */
+ if (max_load > dbs_tuners_ins.up_threshold) {
+ this_dbs_info->down_skip = 0;
+
+ /* if we are already at full speed then break out early */
+ if (this_dbs_info->requested_freq == policy->max)
+ return;
+
+ freq_target = (dbs_tuners_ins.freq_step * policy->max) / 100;
+
+ /* max freq cannot be less than 100. But who knows.... */
+ if (unlikely(freq_target == 0))
+ freq_target = 5;
+
+ this_dbs_info->requested_freq += freq_target;
+ if (this_dbs_info->requested_freq > policy->max)
+ this_dbs_info->requested_freq = policy->max;
+
+ __cpufreq_driver_target(policy, this_dbs_info->requested_freq,
+ CPUFREQ_RELATION_H);
+ return;
+ }
+
+ /*
+ * The optimal frequency is the frequency that is the lowest that
+ * can support the current CPU usage without triggering the up
+ * policy. To be safe, we focus 10 points under the threshold.
+ */
+ if (max_load < (dbs_tuners_ins.down_threshold - 10)) {
+ freq_target = (dbs_tuners_ins.freq_step * policy->max) / 100;
+
+ this_dbs_info->requested_freq -= freq_target;
+ if (this_dbs_info->requested_freq < policy->min)
+ this_dbs_info->requested_freq = policy->min;
+
+ /*
+ * if we cannot reduce the frequency anymore, break out early
+ */
+ if (policy->cur == policy->min)
+ return;
+
+ __cpufreq_driver_target(policy, this_dbs_info->requested_freq,
+ CPUFREQ_RELATION_H);
+ return;
+ }
+}
+
+static void do_dbs_timer(struct work_struct *work)
+{
+ struct cpu_dbs_info_s *dbs_info =
+ container_of(work, struct cpu_dbs_info_s, work.work);
+ unsigned int cpu = dbs_info->cpu;
+
+ /* We want all CPUs to do sampling nearly on same jiffy */
+ int delay = usecs_to_jiffies(dbs_tuners_ins.sampling_rate);
+
+ delay -= jiffies % delay;
+
+ mutex_lock(&dbs_info->timer_mutex);
+
+ dbs_check_cpu(dbs_info);
+
+ schedule_delayed_work_on(cpu, &dbs_info->work, delay);
+ mutex_unlock(&dbs_info->timer_mutex);
+}
+
+static inline void dbs_timer_init(struct cpu_dbs_info_s *dbs_info)
+{
+ /* We want all CPUs to do sampling nearly on same jiffy */
+ int delay = usecs_to_jiffies(dbs_tuners_ins.sampling_rate);
+ delay -= jiffies % delay;
+
+ dbs_info->enable = 1;
+ INIT_DELAYED_WORK_DEFERRABLE(&dbs_info->work, do_dbs_timer);
+ schedule_delayed_work_on(dbs_info->cpu, &dbs_info->work, delay);
+}
+
+static inline void dbs_timer_exit(struct cpu_dbs_info_s *dbs_info)
+{
+ dbs_info->enable = 0;
+ cancel_delayed_work_sync(&dbs_info->work);
+}
+
+static int cpufreq_governor_dbs(struct cpufreq_policy *policy,
+ unsigned int event)
+{
+ unsigned int cpu = policy->cpu;
+ struct cpu_dbs_info_s *this_dbs_info;
+ unsigned int j;
+ int rc;
+
+ this_dbs_info = &per_cpu(cs_cpu_dbs_info, cpu);
+
+ switch (event) {
+ case CPUFREQ_GOV_START:
+ if ((!cpu_online(cpu)) || (!policy->cur))
+ return -EINVAL;
+
+ mutex_lock(&dbs_mutex);
+
+ for_each_cpu(j, policy->cpus) {
+ struct cpu_dbs_info_s *j_dbs_info;
+ j_dbs_info = &per_cpu(cs_cpu_dbs_info, j);
+ j_dbs_info->cur_policy = policy;
+
+ j_dbs_info->prev_cpu_idle = get_cpu_idle_time(j,
+ &j_dbs_info->prev_cpu_wall);
+ if (dbs_tuners_ins.ignore_nice)
+ j_dbs_info->prev_cpu_nice =
+ kcpustat_cpu(j).cpustat[CPUTIME_NICE];
+ }
+ this_dbs_info->down_skip = 0;
+ this_dbs_info->requested_freq = policy->cur;
+
+ mutex_init(&this_dbs_info->timer_mutex);
+ dbs_enable++;
+ /*
+ * Start the timerschedule work, when this governor
+ * is used for first time
+ */
+ if (dbs_enable == 1) {
+ unsigned int latency;
+ /* policy latency is in nS. Convert it to uS first */
+ latency = policy->cpuinfo.transition_latency / 1000;
+ if (latency == 0)
+ latency = 1;
+
+ rc = sysfs_create_group(cpufreq_global_kobject,
+ &dbs_attr_group);
+ if (rc) {
+ mutex_unlock(&dbs_mutex);
+ return rc;
+ }
+
+ /*
+ * conservative does not implement micro like ondemand
+ * governor, thus we are bound to jiffes/HZ
+ */
+ min_sampling_rate =
+ MIN_SAMPLING_RATE_RATIO * jiffies_to_usecs(10);
+ /* Bring kernel and HW constraints together */
+ min_sampling_rate = max(min_sampling_rate,
+ MIN_LATENCY_MULTIPLIER * latency);
+ dbs_tuners_ins.sampling_rate =
+ max(min_sampling_rate,
+ latency * LATENCY_MULTIPLIER);
+
+ cpufreq_register_notifier(
+ &dbs_cpufreq_notifier_block,
+ CPUFREQ_TRANSITION_NOTIFIER);
+ }
+ mutex_unlock(&dbs_mutex);
+
+ dbs_timer_init(this_dbs_info);
+
+ break;
+
+ case CPUFREQ_GOV_STOP:
+ dbs_timer_exit(this_dbs_info);
+
+ mutex_lock(&dbs_mutex);
+ dbs_enable--;
+ mutex_destroy(&this_dbs_info->timer_mutex);
+
+ /*
+ * Stop the timerschedule work, when this governor
+ * is used for first time
+ */
+ if (dbs_enable == 0)
+ cpufreq_unregister_notifier(
+ &dbs_cpufreq_notifier_block,
+ CPUFREQ_TRANSITION_NOTIFIER);
+
+ mutex_unlock(&dbs_mutex);
+ if (!dbs_enable)
+ sysfs_remove_group(cpufreq_global_kobject,
+ &dbs_attr_group);
+
+ break;
+
+ case CPUFREQ_GOV_LIMITS:
+ mutex_lock(&this_dbs_info->timer_mutex);
+ if (policy->max < this_dbs_info->cur_policy->cur)
+ __cpufreq_driver_target(
+ this_dbs_info->cur_policy,
+ policy->max, CPUFREQ_RELATION_H);
+ else if (policy->min > this_dbs_info->cur_policy->cur)
+ __cpufreq_driver_target(
+ this_dbs_info->cur_policy,
+ policy->min, CPUFREQ_RELATION_L);
+ mutex_unlock(&this_dbs_info->timer_mutex);
+
+ break;
+ }
+ return 0;
+}
+
+#ifndef CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
+static
+#endif
+struct cpufreq_governor cpufreq_gov_conservative = {
+ .name = "conservative",
+ .governor = cpufreq_governor_dbs,
+ .max_transition_latency = TRANSITION_LATENCY_LIMIT,
+ .owner = THIS_MODULE,
+};
+
+static int __init cpufreq_gov_dbs_init(void)
+{
+ return cpufreq_register_governor(&cpufreq_gov_conservative);
+}
+
+static void __exit cpufreq_gov_dbs_exit(void)
+{
+ cpufreq_unregister_governor(&cpufreq_gov_conservative);
+}
+
+
+MODULE_AUTHOR("Alexander Clouter <alex@digriz.org.uk>");
+MODULE_DESCRIPTION("'cpufreq_conservative' - A dynamic cpufreq governor for "
+ "Low Latency Frequency Transition capable processors "
+ "optimised for use in a battery environment");
+MODULE_LICENSE("GPL");
+
+#ifdef CONFIG_CPU_FREQ_DEFAULT_GOV_CONSERVATIVE
+fs_initcall(cpufreq_gov_dbs_init);
+#else
+module_init(cpufreq_gov_dbs_init);
+#endif
+module_exit(cpufreq_gov_dbs_exit);