1 files changed, 271 insertions, 5 deletions

diff --git a/drivers/cpufreq/cpufreq_governor.c b/drivers/cpufreq/cpufreq_governor.c
index 679842a8d34a..5ea2c829a796 100644
--- a/drivers/cpufreq/cpufreq_governor.c
+++ b/drivers/cpufreq/cpufreq_governor.c
@@ -3,19 +3,31 @@
  *
  * 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.
  */
 
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
 #include <asm/cputime.h>
+#include <linux/cpufreq.h>
+#include <linux/cpumask.h>
 #include <linux/export.h>
 #include <linux/kernel_stat.h>
+#include <linux/mutex.h>
 #include <linux/tick.h>
 #include <linux/types.h>
-/*
- * Code picked from earlier governer implementations
- */
+#include <linux/workqueue.h>
+
+#include "cpufreq_governor.h"
+
 static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall)
 {
         u64 idle_time;
@@ -33,9 +45,9 @@ static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall)
 
         idle_time = cur_wall_time - busy_time;
         if (wall)
-                *wall = cputime_to_usecs(cur_wall_time);
+                *wall = jiffies_to_usecs(cur_wall_time);
 
-        return cputime_to_usecs(idle_time);
+        return jiffies_to_usecs(idle_time);
 }
 
 cputime64_t get_cpu_idle_time(unsigned int cpu, cputime64_t *wall)
@@ -50,3 +62,257 @@ cputime64_t get_cpu_idle_time(unsigned int cpu, cputime64_t *wall)
         return idle_time;
 }
 EXPORT_SYMBOL_GPL(get_cpu_idle_time);
+
+void dbs_check_cpu(struct dbs_data *dbs_data, int cpu)
+{
+        struct cpu_dbs_common_info *cdbs = dbs_data->get_cpu_cdbs(cpu);
+        struct od_dbs_tuners *od_tuners = dbs_data->tuners;
+        struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
+        struct cpufreq_policy *policy;
+        unsigned int max_load = 0;
+        unsigned int ignore_nice;
+        unsigned int j;
+
+        if (dbs_data->governor == GOV_ONDEMAND)
+                ignore_nice = od_tuners->ignore_nice;
+        else
+                ignore_nice = cs_tuners->ignore_nice;
+
+        policy = cdbs->cur_policy;
+
+        /* Get Absolute Load (in terms of freq for ondemand gov) */
+        for_each_cpu(j, policy->cpus) {
+                struct cpu_dbs_common_info *j_cdbs;
+                cputime64_t cur_wall_time, cur_idle_time, cur_iowait_time;
+                unsigned int idle_time, wall_time, iowait_time;
+                unsigned int load;
+
+                j_cdbs = dbs_data->get_cpu_cdbs(j);
+
+                cur_idle_time = get_cpu_idle_time(j, &cur_wall_time);
+
+                wall_time = (unsigned int)
+                        (cur_wall_time - j_cdbs->prev_cpu_wall);
+                j_cdbs->prev_cpu_wall = cur_wall_time;
+
+                idle_time = (unsigned int)
+                        (cur_idle_time - j_cdbs->prev_cpu_idle);
+                j_cdbs->prev_cpu_idle = cur_idle_time;
+
+                if (ignore_nice) {
+                        u64 cur_nice;
+                        unsigned long cur_nice_jiffies;
+
+                        cur_nice = kcpustat_cpu(j).cpustat[CPUTIME_NICE] -
+                                         cdbs->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);
+
+                        cdbs->prev_cpu_nice =
+                                kcpustat_cpu(j).cpustat[CPUTIME_NICE];
+                        idle_time += jiffies_to_usecs(cur_nice_jiffies);
+                }
+
+                if (dbs_data->governor == GOV_ONDEMAND) {
+                        struct od_cpu_dbs_info_s *od_j_dbs_info =
+                                dbs_data->get_cpu_dbs_info_s(cpu);
+
+                        cur_iowait_time = get_cpu_iowait_time_us(j,
+                                        &cur_wall_time);
+                        if (cur_iowait_time == -1ULL)
+                                cur_iowait_time = 0;
+
+                        iowait_time = (unsigned int) (cur_iowait_time -
+                                        od_j_dbs_info->prev_cpu_iowait);
+                        od_j_dbs_info->prev_cpu_iowait = cur_iowait_time;
+
+                        /*
+                         * For the purpose of ondemand, waiting for disk IO is
+                         * an indication that you're performance critical, and
+                         * not that the system is actually idle. So subtract the
+                         * iowait time from the cpu idle time.
+                         */
+                        if (od_tuners->io_is_busy && idle_time >= iowait_time)
+                                idle_time -= iowait_time;
+                }
+
+                if (unlikely(!wall_time || wall_time < idle_time))
+                        continue;
+
+                load = 100 * (wall_time - idle_time) / wall_time;
+
+                if (dbs_data->governor == GOV_ONDEMAND) {
+                        int freq_avg = __cpufreq_driver_getavg(policy, j);
+                        if (freq_avg <= 0)
+                                freq_avg = policy->cur;
+
+                        load *= freq_avg;
+                }
+
+                if (load > max_load)
+                        max_load = load;
+        }
+
+        dbs_data->gov_check_cpu(cpu, max_load);
+}
+EXPORT_SYMBOL_GPL(dbs_check_cpu);
+
+static inline void dbs_timer_init(struct dbs_data *dbs_data,
+                struct cpu_dbs_common_info *cdbs, unsigned int sampling_rate)
+{
+        int delay = delay_for_sampling_rate(sampling_rate);
+
+        INIT_DEFERRABLE_WORK(&cdbs->work, dbs_data->gov_dbs_timer);
+        schedule_delayed_work_on(cdbs->cpu, &cdbs->work, delay);
+}
+
+static inline void dbs_timer_exit(struct cpu_dbs_common_info *cdbs)
+{
+        cancel_delayed_work_sync(&cdbs->work);
+}
+
+int cpufreq_governor_dbs(struct dbs_data *dbs_data,
+                struct cpufreq_policy *policy, unsigned int event)
+{
+        struct od_cpu_dbs_info_s *od_dbs_info = NULL;
+        struct cs_cpu_dbs_info_s *cs_dbs_info = NULL;
+        struct od_dbs_tuners *od_tuners = dbs_data->tuners;
+        struct cs_dbs_tuners *cs_tuners = dbs_data->tuners;
+        struct cpu_dbs_common_info *cpu_cdbs;
+        unsigned int *sampling_rate, latency, ignore_nice, j, cpu = policy->cpu;
+        int rc;
+
+        cpu_cdbs = dbs_data->get_cpu_cdbs(cpu);
+
+        if (dbs_data->governor == GOV_CONSERVATIVE) {
+                cs_dbs_info = dbs_data->get_cpu_dbs_info_s(cpu);
+                sampling_rate = &cs_tuners->sampling_rate;
+                ignore_nice = cs_tuners->ignore_nice;
+        } else {
+                od_dbs_info = dbs_data->get_cpu_dbs_info_s(cpu);
+                sampling_rate = &od_tuners->sampling_rate;
+                ignore_nice = od_tuners->ignore_nice;
+        }
+
+        switch (event) {
+        case CPUFREQ_GOV_START:
+                if ((!cpu_online(cpu)) || (!policy->cur))
+                        return -EINVAL;
+
+                mutex_lock(&dbs_data->mutex);
+
+                dbs_data->enable++;
+                cpu_cdbs->cpu = cpu;
+                for_each_cpu(j, policy->cpus) {
+                        struct cpu_dbs_common_info *j_cdbs;
+                        j_cdbs = dbs_data->get_cpu_cdbs(j);
+
+                        j_cdbs->cur_policy = policy;
+                        j_cdbs->prev_cpu_idle = get_cpu_idle_time(j,
+                                        &j_cdbs->prev_cpu_wall);
+                        if (ignore_nice)
+                                j_cdbs->prev_cpu_nice =
+                                        kcpustat_cpu(j).cpustat[CPUTIME_NICE];
+                }
+
+                /*
+                 * Start the timerschedule work, when this governor is used for
+                 * first time
+                 */
+                if (dbs_data->enable != 1)
+                        goto second_time;
+
+                rc = sysfs_create_group(cpufreq_global_kobject,
+                                dbs_data->attr_group);
+                if (rc) {
+                        mutex_unlock(&dbs_data->mutex);
+                        return rc;
+                }
+
+                /* policy latency is in nS. Convert it to uS first */
+                latency = policy->cpuinfo.transition_latency / 1000;
+                if (latency == 0)
+                        latency = 1;
+
+                /*
+                 * conservative does not implement micro like ondemand
+                 * governor, thus we are bound to jiffes/HZ
+                 */
+                if (dbs_data->governor == GOV_CONSERVATIVE) {
+                        struct cs_ops *ops = dbs_data->gov_ops;
+
+                        cpufreq_register_notifier(ops->notifier_block,
+                                        CPUFREQ_TRANSITION_NOTIFIER);
+
+                        dbs_data->min_sampling_rate = MIN_SAMPLING_RATE_RATIO *
+                                jiffies_to_usecs(10);
+                } else {
+                        struct od_ops *ops = dbs_data->gov_ops;
+
+                        od_tuners->io_is_busy = ops->io_busy();
+                }
+
+                /* Bring kernel and HW constraints together */
+                dbs_data->min_sampling_rate = max(dbs_data->min_sampling_rate,
+                                MIN_LATENCY_MULTIPLIER * latency);
+                *sampling_rate = max(dbs_data->min_sampling_rate, latency *
+                                LATENCY_MULTIPLIER);
+
+second_time:
+                if (dbs_data->governor == GOV_CONSERVATIVE) {
+                        cs_dbs_info->down_skip = 0;
+                        cs_dbs_info->enable = 1;
+                        cs_dbs_info->requested_freq = policy->cur;
+                } else {
+                        struct od_ops *ops = dbs_data->gov_ops;
+                        od_dbs_info->rate_mult = 1;
+                        od_dbs_info->sample_type = OD_NORMAL_SAMPLE;
+                        ops->powersave_bias_init_cpu(cpu);
+                }
+                mutex_unlock(&dbs_data->mutex);
+
+                mutex_init(&cpu_cdbs->timer_mutex);
+                dbs_timer_init(dbs_data, cpu_cdbs, *sampling_rate);
+                break;
+
+        case CPUFREQ_GOV_STOP:
+                if (dbs_data->governor == GOV_CONSERVATIVE)
+                        cs_dbs_info->enable = 0;
+
+                dbs_timer_exit(cpu_cdbs);
+
+                mutex_lock(&dbs_data->mutex);
+                mutex_destroy(&cpu_cdbs->timer_mutex);
+                dbs_data->enable--;
+                if (!dbs_data->enable) {
+                        struct cs_ops *ops = dbs_data->gov_ops;
+
+                        sysfs_remove_group(cpufreq_global_kobject,
+                                        dbs_data->attr_group);
+                        if (dbs_data->governor == GOV_CONSERVATIVE)
+                                cpufreq_unregister_notifier(ops->notifier_block,
+                                                CPUFREQ_TRANSITION_NOTIFIER);
+                }
+                mutex_unlock(&dbs_data->mutex);
+
+                break;
+
+        case CPUFREQ_GOV_LIMITS:
+                mutex_lock(&cpu_cdbs->timer_mutex);
+                if (policy->max < cpu_cdbs->cur_policy->cur)
+                        __cpufreq_driver_target(cpu_cdbs->cur_policy,
+                                        policy->max, CPUFREQ_RELATION_H);
+                else if (policy->min > cpu_cdbs->cur_policy->cur)
+                        __cpufreq_driver_target(cpu_cdbs->cur_policy,
+                                        policy->min, CPUFREQ_RELATION_L);
+                dbs_check_cpu(dbs_data, cpu);
+                mutex_unlock(&cpu_cdbs->timer_mutex);
+                break;
+        }
+        return 0;
+}
+EXPORT_SYMBOL_GPL(cpufreq_governor_dbs);