v4.19.13 snapshot.
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
new file mode 100644
index 0000000..f53fb41
--- /dev/null
+++ b/drivers/cpufreq/cpufreq.c
@@ -0,0 +1,2608 @@
+/*
+ * linux/drivers/cpufreq/cpufreq.c
+ *
+ * Copyright (C) 2001 Russell King
+ * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de>
+ * (C) 2013 Viresh Kumar <viresh.kumar@linaro.org>
+ *
+ * Oct 2005 - Ashok Raj <ashok.raj@intel.com>
+ * Added handling for CPU hotplug
+ * Feb 2006 - Jacob Shin <jacob.shin@amd.com>
+ * Fix handling for CPU hotplug -- affected CPUs
+ *
+ * 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 <linux/cpu.h>
+#include <linux/cpufreq.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/init.h>
+#include <linux/kernel_stat.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <linux/suspend.h>
+#include <linux/syscore_ops.h>
+#include <linux/tick.h>
+#include <trace/events/power.h>
+
+static LIST_HEAD(cpufreq_policy_list);
+
+static inline bool policy_is_inactive(struct cpufreq_policy *policy)
+{
+ return cpumask_empty(policy->cpus);
+}
+
+/* Macros to iterate over CPU policies */
+#define for_each_suitable_policy(__policy, __active) \
+ list_for_each_entry(__policy, &cpufreq_policy_list, policy_list) \
+ if ((__active) == !policy_is_inactive(__policy))
+
+#define for_each_active_policy(__policy) \
+ for_each_suitable_policy(__policy, true)
+#define for_each_inactive_policy(__policy) \
+ for_each_suitable_policy(__policy, false)
+
+#define for_each_policy(__policy) \
+ list_for_each_entry(__policy, &cpufreq_policy_list, policy_list)
+
+/* Iterate over governors */
+static LIST_HEAD(cpufreq_governor_list);
+#define for_each_governor(__governor) \
+ list_for_each_entry(__governor, &cpufreq_governor_list, governor_list)
+
+/**
+ * The "cpufreq driver" - the arch- or hardware-dependent low
+ * level driver of CPUFreq support, and its spinlock. This lock
+ * also protects the cpufreq_cpu_data array.
+ */
+static struct cpufreq_driver *cpufreq_driver;
+static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data);
+static DEFINE_RWLOCK(cpufreq_driver_lock);
+
+/* Flag to suspend/resume CPUFreq governors */
+static bool cpufreq_suspended;
+
+static inline bool has_target(void)
+{
+ return cpufreq_driver->target_index || cpufreq_driver->target;
+}
+
+/* internal prototypes */
+static unsigned int __cpufreq_get(struct cpufreq_policy *policy);
+static int cpufreq_init_governor(struct cpufreq_policy *policy);
+static void cpufreq_exit_governor(struct cpufreq_policy *policy);
+static int cpufreq_start_governor(struct cpufreq_policy *policy);
+static void cpufreq_stop_governor(struct cpufreq_policy *policy);
+static void cpufreq_governor_limits(struct cpufreq_policy *policy);
+
+/**
+ * Two notifier lists: the "policy" list is involved in the
+ * validation process for a new CPU frequency policy; the
+ * "transition" list for kernel code that needs to handle
+ * changes to devices when the CPU clock speed changes.
+ * The mutex locks both lists.
+ */
+static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list);
+SRCU_NOTIFIER_HEAD_STATIC(cpufreq_transition_notifier_list);
+
+static int off __read_mostly;
+static int cpufreq_disabled(void)
+{
+ return off;
+}
+void disable_cpufreq(void)
+{
+ off = 1;
+}
+static DEFINE_MUTEX(cpufreq_governor_mutex);
+
+bool have_governor_per_policy(void)
+{
+ return !!(cpufreq_driver->flags & CPUFREQ_HAVE_GOVERNOR_PER_POLICY);
+}
+EXPORT_SYMBOL_GPL(have_governor_per_policy);
+
+struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy)
+{
+ if (have_governor_per_policy())
+ return &policy->kobj;
+ else
+ return cpufreq_global_kobject;
+}
+EXPORT_SYMBOL_GPL(get_governor_parent_kobj);
+
+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_nsecs(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 = div_u64(cur_wall_time, NSEC_PER_USEC);
+
+ return div_u64(idle_time, NSEC_PER_USEC);
+}
+
+u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy)
+{
+ u64 idle_time = get_cpu_idle_time_us(cpu, io_busy ? wall : NULL);
+
+ if (idle_time == -1ULL)
+ return get_cpu_idle_time_jiffy(cpu, wall);
+ else if (!io_busy)
+ idle_time += get_cpu_iowait_time_us(cpu, wall);
+
+ return idle_time;
+}
+EXPORT_SYMBOL_GPL(get_cpu_idle_time);
+
+__weak void arch_set_freq_scale(struct cpumask *cpus, unsigned long cur_freq,
+ unsigned long max_freq)
+{
+}
+EXPORT_SYMBOL_GPL(arch_set_freq_scale);
+
+/*
+ * This is a generic cpufreq init() routine which can be used by cpufreq
+ * drivers of SMP systems. It will do following:
+ * - validate & show freq table passed
+ * - set policies transition latency
+ * - policy->cpus with all possible CPUs
+ */
+int cpufreq_generic_init(struct cpufreq_policy *policy,
+ struct cpufreq_frequency_table *table,
+ unsigned int transition_latency)
+{
+ policy->freq_table = table;
+ policy->cpuinfo.transition_latency = transition_latency;
+
+ /*
+ * The driver only supports the SMP configuration where all processors
+ * share the clock and voltage and clock.
+ */
+ cpumask_setall(policy->cpus);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(cpufreq_generic_init);
+
+struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu)
+{
+ struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu);
+
+ return policy && cpumask_test_cpu(cpu, policy->cpus) ? policy : NULL;
+}
+EXPORT_SYMBOL_GPL(cpufreq_cpu_get_raw);
+
+unsigned int cpufreq_generic_get(unsigned int cpu)
+{
+ struct cpufreq_policy *policy = cpufreq_cpu_get_raw(cpu);
+
+ if (!policy || IS_ERR(policy->clk)) {
+ pr_err("%s: No %s associated to cpu: %d\n",
+ __func__, policy ? "clk" : "policy", cpu);
+ return 0;
+ }
+
+ return clk_get_rate(policy->clk) / 1000;
+}
+EXPORT_SYMBOL_GPL(cpufreq_generic_get);
+
+/**
+ * cpufreq_cpu_get: returns policy for a cpu and marks it busy.
+ *
+ * @cpu: cpu to find policy for.
+ *
+ * This returns policy for 'cpu', returns NULL if it doesn't exist.
+ * It also increments the kobject reference count to mark it busy and so would
+ * require a corresponding call to cpufreq_cpu_put() to decrement it back.
+ * If corresponding call cpufreq_cpu_put() isn't made, the policy wouldn't be
+ * freed as that depends on the kobj count.
+ *
+ * Return: A valid policy on success, otherwise NULL on failure.
+ */
+struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu)
+{
+ struct cpufreq_policy *policy = NULL;
+ unsigned long flags;
+
+ if (WARN_ON(cpu >= nr_cpu_ids))
+ return NULL;
+
+ /* get the cpufreq driver */
+ read_lock_irqsave(&cpufreq_driver_lock, flags);
+
+ if (cpufreq_driver) {
+ /* get the CPU */
+ policy = cpufreq_cpu_get_raw(cpu);
+ if (policy)
+ kobject_get(&policy->kobj);
+ }
+
+ read_unlock_irqrestore(&cpufreq_driver_lock, flags);
+
+ return policy;
+}
+EXPORT_SYMBOL_GPL(cpufreq_cpu_get);
+
+/**
+ * cpufreq_cpu_put: Decrements the usage count of a policy
+ *
+ * @policy: policy earlier returned by cpufreq_cpu_get().
+ *
+ * This decrements the kobject reference count incremented earlier by calling
+ * cpufreq_cpu_get().
+ */
+void cpufreq_cpu_put(struct cpufreq_policy *policy)
+{
+ kobject_put(&policy->kobj);
+}
+EXPORT_SYMBOL_GPL(cpufreq_cpu_put);
+
+/*********************************************************************
+ * EXTERNALLY AFFECTING FREQUENCY CHANGES *
+ *********************************************************************/
+
+/**
+ * adjust_jiffies - adjust the system "loops_per_jiffy"
+ *
+ * This function alters the system "loops_per_jiffy" for the clock
+ * speed change. Note that loops_per_jiffy cannot be updated on SMP
+ * systems as each CPU might be scaled differently. So, use the arch
+ * per-CPU loops_per_jiffy value wherever possible.
+ */
+static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci)
+{
+#ifndef CONFIG_SMP
+ static unsigned long l_p_j_ref;
+ static unsigned int l_p_j_ref_freq;
+
+ if (ci->flags & CPUFREQ_CONST_LOOPS)
+ return;
+
+ if (!l_p_j_ref_freq) {
+ l_p_j_ref = loops_per_jiffy;
+ l_p_j_ref_freq = ci->old;
+ pr_debug("saving %lu as reference value for loops_per_jiffy; freq is %u kHz\n",
+ l_p_j_ref, l_p_j_ref_freq);
+ }
+ if (val == CPUFREQ_POSTCHANGE && ci->old != ci->new) {
+ loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq,
+ ci->new);
+ pr_debug("scaling loops_per_jiffy to %lu for frequency %u kHz\n",
+ loops_per_jiffy, ci->new);
+ }
+#endif
+}
+
+/**
+ * cpufreq_notify_transition - Notify frequency transition and adjust_jiffies.
+ * @policy: cpufreq policy to enable fast frequency switching for.
+ * @freqs: contain details of the frequency update.
+ * @state: set to CPUFREQ_PRECHANGE or CPUFREQ_POSTCHANGE.
+ *
+ * This function calls the transition notifiers and the "adjust_jiffies"
+ * function. It is called twice on all CPU frequency changes that have
+ * external effects.
+ */
+static void cpufreq_notify_transition(struct cpufreq_policy *policy,
+ struct cpufreq_freqs *freqs,
+ unsigned int state)
+{
+ BUG_ON(irqs_disabled());
+
+ if (cpufreq_disabled())
+ return;
+
+ freqs->flags = cpufreq_driver->flags;
+ pr_debug("notification %u of frequency transition to %u kHz\n",
+ state, freqs->new);
+
+ switch (state) {
+ case CPUFREQ_PRECHANGE:
+ /*
+ * Detect if the driver reported a value as "old frequency"
+ * which is not equal to what the cpufreq core thinks is
+ * "old frequency".
+ */
+ if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) {
+ if (policy->cur && (policy->cur != freqs->old)) {
+ pr_debug("Warning: CPU frequency is %u, cpufreq assumed %u kHz\n",
+ freqs->old, policy->cur);
+ freqs->old = policy->cur;
+ }
+ }
+
+ for_each_cpu(freqs->cpu, policy->cpus) {
+ srcu_notifier_call_chain(&cpufreq_transition_notifier_list,
+ CPUFREQ_PRECHANGE, freqs);
+ }
+
+ adjust_jiffies(CPUFREQ_PRECHANGE, freqs);
+ break;
+
+ case CPUFREQ_POSTCHANGE:
+ adjust_jiffies(CPUFREQ_POSTCHANGE, freqs);
+ pr_debug("FREQ: %u - CPUs: %*pbl\n", freqs->new,
+ cpumask_pr_args(policy->cpus));
+
+ for_each_cpu(freqs->cpu, policy->cpus) {
+ trace_cpu_frequency(freqs->new, freqs->cpu);
+ srcu_notifier_call_chain(&cpufreq_transition_notifier_list,
+ CPUFREQ_POSTCHANGE, freqs);
+ }
+
+ cpufreq_stats_record_transition(policy, freqs->new);
+ policy->cur = freqs->new;
+ }
+}
+
+/* Do post notifications when there are chances that transition has failed */
+static void cpufreq_notify_post_transition(struct cpufreq_policy *policy,
+ struct cpufreq_freqs *freqs, int transition_failed)
+{
+ cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE);
+ if (!transition_failed)
+ return;
+
+ swap(freqs->old, freqs->new);
+ cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE);
+ cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE);
+}
+
+void cpufreq_freq_transition_begin(struct cpufreq_policy *policy,
+ struct cpufreq_freqs *freqs)
+{
+
+ /*
+ * Catch double invocations of _begin() which lead to self-deadlock.
+ * ASYNC_NOTIFICATION drivers are left out because the cpufreq core
+ * doesn't invoke _begin() on their behalf, and hence the chances of
+ * double invocations are very low. Moreover, there are scenarios
+ * where these checks can emit false-positive warnings in these
+ * drivers; so we avoid that by skipping them altogether.
+ */
+ WARN_ON(!(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION)
+ && current == policy->transition_task);
+
+wait:
+ wait_event(policy->transition_wait, !policy->transition_ongoing);
+
+ spin_lock(&policy->transition_lock);
+
+ if (unlikely(policy->transition_ongoing)) {
+ spin_unlock(&policy->transition_lock);
+ goto wait;
+ }
+
+ policy->transition_ongoing = true;
+ policy->transition_task = current;
+
+ spin_unlock(&policy->transition_lock);
+
+ cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE);
+}
+EXPORT_SYMBOL_GPL(cpufreq_freq_transition_begin);
+
+void cpufreq_freq_transition_end(struct cpufreq_policy *policy,
+ struct cpufreq_freqs *freqs, int transition_failed)
+{
+ if (unlikely(WARN_ON(!policy->transition_ongoing)))
+ return;
+
+ cpufreq_notify_post_transition(policy, freqs, transition_failed);
+
+ policy->transition_ongoing = false;
+ policy->transition_task = NULL;
+
+ wake_up(&policy->transition_wait);
+}
+EXPORT_SYMBOL_GPL(cpufreq_freq_transition_end);
+
+/*
+ * Fast frequency switching status count. Positive means "enabled", negative
+ * means "disabled" and 0 means "not decided yet".
+ */
+static int cpufreq_fast_switch_count;
+static DEFINE_MUTEX(cpufreq_fast_switch_lock);
+
+static void cpufreq_list_transition_notifiers(void)
+{
+ struct notifier_block *nb;
+
+ pr_info("Registered transition notifiers:\n");
+
+ mutex_lock(&cpufreq_transition_notifier_list.mutex);
+
+ for (nb = cpufreq_transition_notifier_list.head; nb; nb = nb->next)
+ pr_info("%pF\n", nb->notifier_call);
+
+ mutex_unlock(&cpufreq_transition_notifier_list.mutex);
+}
+
+/**
+ * cpufreq_enable_fast_switch - Enable fast frequency switching for policy.
+ * @policy: cpufreq policy to enable fast frequency switching for.
+ *
+ * Try to enable fast frequency switching for @policy.
+ *
+ * The attempt will fail if there is at least one transition notifier registered
+ * at this point, as fast frequency switching is quite fundamentally at odds
+ * with transition notifiers. Thus if successful, it will make registration of
+ * transition notifiers fail going forward.
+ */
+void cpufreq_enable_fast_switch(struct cpufreq_policy *policy)
+{
+ lockdep_assert_held(&policy->rwsem);
+
+ if (!policy->fast_switch_possible)
+ return;
+
+ mutex_lock(&cpufreq_fast_switch_lock);
+ if (cpufreq_fast_switch_count >= 0) {
+ cpufreq_fast_switch_count++;
+ policy->fast_switch_enabled = true;
+ } else {
+ pr_warn("CPU%u: Fast frequency switching not enabled\n",
+ policy->cpu);
+ cpufreq_list_transition_notifiers();
+ }
+ mutex_unlock(&cpufreq_fast_switch_lock);
+}
+EXPORT_SYMBOL_GPL(cpufreq_enable_fast_switch);
+
+/**
+ * cpufreq_disable_fast_switch - Disable fast frequency switching for policy.
+ * @policy: cpufreq policy to disable fast frequency switching for.
+ */
+void cpufreq_disable_fast_switch(struct cpufreq_policy *policy)
+{
+ mutex_lock(&cpufreq_fast_switch_lock);
+ if (policy->fast_switch_enabled) {
+ policy->fast_switch_enabled = false;
+ if (!WARN_ON(cpufreq_fast_switch_count <= 0))
+ cpufreq_fast_switch_count--;
+ }
+ mutex_unlock(&cpufreq_fast_switch_lock);
+}
+EXPORT_SYMBOL_GPL(cpufreq_disable_fast_switch);
+
+/**
+ * cpufreq_driver_resolve_freq - Map a target frequency to a driver-supported
+ * one.
+ * @target_freq: target frequency to resolve.
+ *
+ * The target to driver frequency mapping is cached in the policy.
+ *
+ * Return: Lowest driver-supported frequency greater than or equal to the
+ * given target_freq, subject to policy (min/max) and driver limitations.
+ */
+unsigned int cpufreq_driver_resolve_freq(struct cpufreq_policy *policy,
+ unsigned int target_freq)
+{
+ target_freq = clamp_val(target_freq, policy->min, policy->max);
+ policy->cached_target_freq = target_freq;
+
+ if (cpufreq_driver->target_index) {
+ int idx;
+
+ idx = cpufreq_frequency_table_target(policy, target_freq,
+ CPUFREQ_RELATION_L);
+ policy->cached_resolved_idx = idx;
+ return policy->freq_table[idx].frequency;
+ }
+
+ if (cpufreq_driver->resolve_freq)
+ return cpufreq_driver->resolve_freq(policy, target_freq);
+
+ return target_freq;
+}
+EXPORT_SYMBOL_GPL(cpufreq_driver_resolve_freq);
+
+unsigned int cpufreq_policy_transition_delay_us(struct cpufreq_policy *policy)
+{
+ unsigned int latency;
+
+ if (policy->transition_delay_us)
+ return policy->transition_delay_us;
+
+ latency = policy->cpuinfo.transition_latency / NSEC_PER_USEC;
+ if (latency) {
+ /*
+ * For platforms that can change the frequency very fast (< 10
+ * us), the above formula gives a decent transition delay. But
+ * for platforms where transition_latency is in milliseconds, it
+ * ends up giving unrealistic values.
+ *
+ * Cap the default transition delay to 10 ms, which seems to be
+ * a reasonable amount of time after which we should reevaluate
+ * the frequency.
+ */
+ return min(latency * LATENCY_MULTIPLIER, (unsigned int)10000);
+ }
+
+ return LATENCY_MULTIPLIER;
+}
+EXPORT_SYMBOL_GPL(cpufreq_policy_transition_delay_us);
+
+/*********************************************************************
+ * SYSFS INTERFACE *
+ *********************************************************************/
+static ssize_t show_boost(struct kobject *kobj,
+ struct attribute *attr, char *buf)
+{
+ return sprintf(buf, "%d\n", cpufreq_driver->boost_enabled);
+}
+
+static ssize_t store_boost(struct kobject *kobj, struct attribute *attr,
+ const char *buf, size_t count)
+{
+ int ret, enable;
+
+ ret = sscanf(buf, "%d", &enable);
+ if (ret != 1 || enable < 0 || enable > 1)
+ return -EINVAL;
+
+ if (cpufreq_boost_trigger_state(enable)) {
+ pr_err("%s: Cannot %s BOOST!\n",
+ __func__, enable ? "enable" : "disable");
+ return -EINVAL;
+ }
+
+ pr_debug("%s: cpufreq BOOST %s\n",
+ __func__, enable ? "enabled" : "disabled");
+
+ return count;
+}
+define_one_global_rw(boost);
+
+static struct cpufreq_governor *find_governor(const char *str_governor)
+{
+ struct cpufreq_governor *t;
+
+ for_each_governor(t)
+ if (!strncasecmp(str_governor, t->name, CPUFREQ_NAME_LEN))
+ return t;
+
+ return NULL;
+}
+
+/**
+ * cpufreq_parse_governor - parse a governor string
+ */
+static int cpufreq_parse_governor(char *str_governor,
+ struct cpufreq_policy *policy)
+{
+ if (cpufreq_driver->setpolicy) {
+ if (!strncasecmp(str_governor, "performance", CPUFREQ_NAME_LEN)) {
+ policy->policy = CPUFREQ_POLICY_PERFORMANCE;
+ return 0;
+ }
+
+ if (!strncasecmp(str_governor, "powersave", CPUFREQ_NAME_LEN)) {
+ policy->policy = CPUFREQ_POLICY_POWERSAVE;
+ return 0;
+ }
+ } else {
+ struct cpufreq_governor *t;
+
+ mutex_lock(&cpufreq_governor_mutex);
+
+ t = find_governor(str_governor);
+ if (!t) {
+ int ret;
+
+ mutex_unlock(&cpufreq_governor_mutex);
+
+ ret = request_module("cpufreq_%s", str_governor);
+ if (ret)
+ return -EINVAL;
+
+ mutex_lock(&cpufreq_governor_mutex);
+
+ t = find_governor(str_governor);
+ }
+ if (t && !try_module_get(t->owner))
+ t = NULL;
+
+ mutex_unlock(&cpufreq_governor_mutex);
+
+ if (t) {
+ policy->governor = t;
+ return 0;
+ }
+ }
+
+ return -EINVAL;
+}
+
+/**
+ * cpufreq_per_cpu_attr_read() / show_##file_name() -
+ * print out cpufreq information
+ *
+ * Write out information from cpufreq_driver->policy[cpu]; object must be
+ * "unsigned int".
+ */
+
+#define show_one(file_name, object) \
+static ssize_t show_##file_name \
+(struct cpufreq_policy *policy, char *buf) \
+{ \
+ return sprintf(buf, "%u\n", policy->object); \
+}
+
+show_one(cpuinfo_min_freq, cpuinfo.min_freq);
+show_one(cpuinfo_max_freq, cpuinfo.max_freq);
+show_one(cpuinfo_transition_latency, cpuinfo.transition_latency);
+show_one(scaling_min_freq, min);
+show_one(scaling_max_freq, max);
+
+__weak unsigned int arch_freq_get_on_cpu(int cpu)
+{
+ return 0;
+}
+
+static ssize_t show_scaling_cur_freq(struct cpufreq_policy *policy, char *buf)
+{
+ ssize_t ret;
+ unsigned int freq;
+
+ freq = arch_freq_get_on_cpu(policy->cpu);
+ if (freq)
+ ret = sprintf(buf, "%u\n", freq);
+ else if (cpufreq_driver && cpufreq_driver->setpolicy &&
+ cpufreq_driver->get)
+ ret = sprintf(buf, "%u\n", cpufreq_driver->get(policy->cpu));
+ else
+ ret = sprintf(buf, "%u\n", policy->cur);
+ return ret;
+}
+
+static int cpufreq_set_policy(struct cpufreq_policy *policy,
+ struct cpufreq_policy *new_policy);
+
+/**
+ * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access
+ */
+#define store_one(file_name, object) \
+static ssize_t store_##file_name \
+(struct cpufreq_policy *policy, const char *buf, size_t count) \
+{ \
+ int ret, temp; \
+ struct cpufreq_policy new_policy; \
+ \
+ memcpy(&new_policy, policy, sizeof(*policy)); \
+ new_policy.min = policy->user_policy.min; \
+ new_policy.max = policy->user_policy.max; \
+ \
+ ret = sscanf(buf, "%u", &new_policy.object); \
+ if (ret != 1) \
+ return -EINVAL; \
+ \
+ temp = new_policy.object; \
+ ret = cpufreq_set_policy(policy, &new_policy); \
+ if (!ret) \
+ policy->user_policy.object = temp; \
+ \
+ return ret ? ret : count; \
+}
+
+store_one(scaling_min_freq, min);
+store_one(scaling_max_freq, max);
+
+/**
+ * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware
+ */
+static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy,
+ char *buf)
+{
+ unsigned int cur_freq = __cpufreq_get(policy);
+
+ if (cur_freq)
+ return sprintf(buf, "%u\n", cur_freq);
+
+ return sprintf(buf, "<unknown>\n");
+}
+
+/**
+ * show_scaling_governor - show the current policy for the specified CPU
+ */
+static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf)
+{
+ if (policy->policy == CPUFREQ_POLICY_POWERSAVE)
+ return sprintf(buf, "powersave\n");
+ else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE)
+ return sprintf(buf, "performance\n");
+ else if (policy->governor)
+ return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n",
+ policy->governor->name);
+ return -EINVAL;
+}
+
+/**
+ * store_scaling_governor - store policy for the specified CPU
+ */
+static ssize_t store_scaling_governor(struct cpufreq_policy *policy,
+ const char *buf, size_t count)
+{
+ int ret;
+ char str_governor[16];
+ struct cpufreq_policy new_policy;
+
+ memcpy(&new_policy, policy, sizeof(*policy));
+
+ ret = sscanf(buf, "%15s", str_governor);
+ if (ret != 1)
+ return -EINVAL;
+
+ if (cpufreq_parse_governor(str_governor, &new_policy))
+ return -EINVAL;
+
+ ret = cpufreq_set_policy(policy, &new_policy);
+
+ if (new_policy.governor)
+ module_put(new_policy.governor->owner);
+
+ return ret ? ret : count;
+}
+
+/**
+ * show_scaling_driver - show the cpufreq driver currently loaded
+ */
+static ssize_t show_scaling_driver(struct cpufreq_policy *policy, char *buf)
+{
+ return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", cpufreq_driver->name);
+}
+
+/**
+ * show_scaling_available_governors - show the available CPUfreq governors
+ */
+static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy,
+ char *buf)
+{
+ ssize_t i = 0;
+ struct cpufreq_governor *t;
+
+ if (!has_target()) {
+ i += sprintf(buf, "performance powersave");
+ goto out;
+ }
+
+ for_each_governor(t) {
+ if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char))
+ - (CPUFREQ_NAME_LEN + 2)))
+ goto out;
+ i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name);
+ }
+out:
+ i += sprintf(&buf[i], "\n");
+ return i;
+}
+
+ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf)
+{
+ ssize_t i = 0;
+ unsigned int cpu;
+
+ for_each_cpu(cpu, mask) {
+ if (i)
+ i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), " ");
+ i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u", cpu);
+ if (i >= (PAGE_SIZE - 5))
+ break;
+ }
+ i += sprintf(&buf[i], "\n");
+ return i;
+}
+EXPORT_SYMBOL_GPL(cpufreq_show_cpus);
+
+/**
+ * show_related_cpus - show the CPUs affected by each transition even if
+ * hw coordination is in use
+ */
+static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf)
+{
+ return cpufreq_show_cpus(policy->related_cpus, buf);
+}
+
+/**
+ * show_affected_cpus - show the CPUs affected by each transition
+ */
+static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf)
+{
+ return cpufreq_show_cpus(policy->cpus, buf);
+}
+
+static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy,
+ const char *buf, size_t count)
+{
+ unsigned int freq = 0;
+ unsigned int ret;
+
+ if (!policy->governor || !policy->governor->store_setspeed)
+ return -EINVAL;
+
+ ret = sscanf(buf, "%u", &freq);
+ if (ret != 1)
+ return -EINVAL;
+
+ policy->governor->store_setspeed(policy, freq);
+
+ return count;
+}
+
+static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf)
+{
+ if (!policy->governor || !policy->governor->show_setspeed)
+ return sprintf(buf, "<unsupported>\n");
+
+ return policy->governor->show_setspeed(policy, buf);
+}
+
+/**
+ * show_bios_limit - show the current cpufreq HW/BIOS limitation
+ */
+static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf)
+{
+ unsigned int limit;
+ int ret;
+ if (cpufreq_driver->bios_limit) {
+ ret = cpufreq_driver->bios_limit(policy->cpu, &limit);
+ if (!ret)
+ return sprintf(buf, "%u\n", limit);
+ }
+ return sprintf(buf, "%u\n", policy->cpuinfo.max_freq);
+}
+
+cpufreq_freq_attr_ro_perm(cpuinfo_cur_freq, 0400);
+cpufreq_freq_attr_ro(cpuinfo_min_freq);
+cpufreq_freq_attr_ro(cpuinfo_max_freq);
+cpufreq_freq_attr_ro(cpuinfo_transition_latency);
+cpufreq_freq_attr_ro(scaling_available_governors);
+cpufreq_freq_attr_ro(scaling_driver);
+cpufreq_freq_attr_ro(scaling_cur_freq);
+cpufreq_freq_attr_ro(bios_limit);
+cpufreq_freq_attr_ro(related_cpus);
+cpufreq_freq_attr_ro(affected_cpus);
+cpufreq_freq_attr_rw(scaling_min_freq);
+cpufreq_freq_attr_rw(scaling_max_freq);
+cpufreq_freq_attr_rw(scaling_governor);
+cpufreq_freq_attr_rw(scaling_setspeed);
+
+static struct attribute *default_attrs[] = {
+ &cpuinfo_min_freq.attr,
+ &cpuinfo_max_freq.attr,
+ &cpuinfo_transition_latency.attr,
+ &scaling_min_freq.attr,
+ &scaling_max_freq.attr,
+ &affected_cpus.attr,
+ &related_cpus.attr,
+ &scaling_governor.attr,
+ &scaling_driver.attr,
+ &scaling_available_governors.attr,
+ &scaling_setspeed.attr,
+ NULL
+};
+
+#define to_policy(k) container_of(k, struct cpufreq_policy, kobj)
+#define to_attr(a) container_of(a, struct freq_attr, attr)
+
+static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf)
+{
+ struct cpufreq_policy *policy = to_policy(kobj);
+ struct freq_attr *fattr = to_attr(attr);
+ ssize_t ret;
+
+ down_read(&policy->rwsem);
+ ret = fattr->show(policy, buf);
+ up_read(&policy->rwsem);
+
+ return ret;
+}
+
+static ssize_t store(struct kobject *kobj, struct attribute *attr,
+ const char *buf, size_t count)
+{
+ struct cpufreq_policy *policy = to_policy(kobj);
+ struct freq_attr *fattr = to_attr(attr);
+ ssize_t ret = -EINVAL;
+
+ /*
+ * cpus_read_trylock() is used here to work around a circular lock
+ * dependency problem with respect to the cpufreq_register_driver().
+ */
+ if (!cpus_read_trylock())
+ return -EBUSY;
+
+ if (cpu_online(policy->cpu)) {
+ down_write(&policy->rwsem);
+ ret = fattr->store(policy, buf, count);
+ up_write(&policy->rwsem);
+ }
+
+ cpus_read_unlock();
+
+ return ret;
+}
+
+static void cpufreq_sysfs_release(struct kobject *kobj)
+{
+ struct cpufreq_policy *policy = to_policy(kobj);
+ pr_debug("last reference is dropped\n");
+ complete(&policy->kobj_unregister);
+}
+
+static const struct sysfs_ops sysfs_ops = {
+ .show = show,
+ .store = store,
+};
+
+static struct kobj_type ktype_cpufreq = {
+ .sysfs_ops = &sysfs_ops,
+ .default_attrs = default_attrs,
+ .release = cpufreq_sysfs_release,
+};
+
+static void add_cpu_dev_symlink(struct cpufreq_policy *policy, unsigned int cpu)
+{
+ struct device *dev = get_cpu_device(cpu);
+
+ if (!dev)
+ return;
+
+ if (cpumask_test_and_set_cpu(cpu, policy->real_cpus))
+ return;
+
+ dev_dbg(dev, "%s: Adding symlink\n", __func__);
+ if (sysfs_create_link(&dev->kobj, &policy->kobj, "cpufreq"))
+ dev_err(dev, "cpufreq symlink creation failed\n");
+}
+
+static void remove_cpu_dev_symlink(struct cpufreq_policy *policy,
+ struct device *dev)
+{
+ dev_dbg(dev, "%s: Removing symlink\n", __func__);
+ sysfs_remove_link(&dev->kobj, "cpufreq");
+}
+
+static int cpufreq_add_dev_interface(struct cpufreq_policy *policy)
+{
+ struct freq_attr **drv_attr;
+ int ret = 0;
+
+ /* set up files for this cpu device */
+ drv_attr = cpufreq_driver->attr;
+ while (drv_attr && *drv_attr) {
+ ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr));
+ if (ret)
+ return ret;
+ drv_attr++;
+ }
+ if (cpufreq_driver->get) {
+ ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr);
+ if (ret)
+ return ret;
+ }
+
+ ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr);
+ if (ret)
+ return ret;
+
+ if (cpufreq_driver->bios_limit) {
+ ret = sysfs_create_file(&policy->kobj, &bios_limit.attr);
+ if (ret)
+ return ret;
+ }
+
+ return 0;
+}
+
+__weak struct cpufreq_governor *cpufreq_default_governor(void)
+{
+ return NULL;
+}
+
+static int cpufreq_init_policy(struct cpufreq_policy *policy)
+{
+ struct cpufreq_governor *gov = NULL;
+ struct cpufreq_policy new_policy;
+
+ memcpy(&new_policy, policy, sizeof(*policy));
+
+ /* Update governor of new_policy to the governor used before hotplug */
+ gov = find_governor(policy->last_governor);
+ if (gov) {
+ pr_debug("Restoring governor %s for cpu %d\n",
+ policy->governor->name, policy->cpu);
+ } else {
+ gov = cpufreq_default_governor();
+ if (!gov)
+ return -ENODATA;
+ }
+
+ new_policy.governor = gov;
+
+ /* Use the default policy if there is no last_policy. */
+ if (cpufreq_driver->setpolicy) {
+ if (policy->last_policy)
+ new_policy.policy = policy->last_policy;
+ else
+ cpufreq_parse_governor(gov->name, &new_policy);
+ }
+ /* set default policy */
+ return cpufreq_set_policy(policy, &new_policy);
+}
+
+static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu)
+{
+ int ret = 0;
+
+ /* Has this CPU been taken care of already? */
+ if (cpumask_test_cpu(cpu, policy->cpus))
+ return 0;
+
+ down_write(&policy->rwsem);
+ if (has_target())
+ cpufreq_stop_governor(policy);
+
+ cpumask_set_cpu(cpu, policy->cpus);
+
+ if (has_target()) {
+ ret = cpufreq_start_governor(policy);
+ if (ret)
+ pr_err("%s: Failed to start governor\n", __func__);
+ }
+ up_write(&policy->rwsem);
+ return ret;
+}
+
+static void handle_update(struct work_struct *work)
+{
+ struct cpufreq_policy *policy =
+ container_of(work, struct cpufreq_policy, update);
+ unsigned int cpu = policy->cpu;
+ pr_debug("handle_update for cpu %u called\n", cpu);
+ cpufreq_update_policy(cpu);
+}
+
+static struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu)
+{
+ struct cpufreq_policy *policy;
+ int ret;
+
+ policy = kzalloc(sizeof(*policy), GFP_KERNEL);
+ if (!policy)
+ return NULL;
+
+ if (!alloc_cpumask_var(&policy->cpus, GFP_KERNEL))
+ goto err_free_policy;
+
+ if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL))
+ goto err_free_cpumask;
+
+ if (!zalloc_cpumask_var(&policy->real_cpus, GFP_KERNEL))
+ goto err_free_rcpumask;
+
+ ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq,
+ cpufreq_global_kobject, "policy%u", cpu);
+ if (ret) {
+ pr_err("%s: failed to init policy->kobj: %d\n", __func__, ret);
+ goto err_free_real_cpus;
+ }
+
+ INIT_LIST_HEAD(&policy->policy_list);
+ init_rwsem(&policy->rwsem);
+ spin_lock_init(&policy->transition_lock);
+ init_waitqueue_head(&policy->transition_wait);
+ init_completion(&policy->kobj_unregister);
+ INIT_WORK(&policy->update, handle_update);
+
+ policy->cpu = cpu;
+ return policy;
+
+err_free_real_cpus:
+ free_cpumask_var(policy->real_cpus);
+err_free_rcpumask:
+ free_cpumask_var(policy->related_cpus);
+err_free_cpumask:
+ free_cpumask_var(policy->cpus);
+err_free_policy:
+ kfree(policy);
+
+ return NULL;
+}
+
+static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy)
+{
+ struct kobject *kobj;
+ struct completion *cmp;
+
+ down_write(&policy->rwsem);
+ cpufreq_stats_free_table(policy);
+ kobj = &policy->kobj;
+ cmp = &policy->kobj_unregister;
+ up_write(&policy->rwsem);
+ kobject_put(kobj);
+
+ /*
+ * We need to make sure that the underlying kobj is
+ * actually not referenced anymore by anybody before we
+ * proceed with unloading.
+ */
+ pr_debug("waiting for dropping of refcount\n");
+ wait_for_completion(cmp);
+ pr_debug("wait complete\n");
+}
+
+static void cpufreq_policy_free(struct cpufreq_policy *policy)
+{
+ unsigned long flags;
+ int cpu;
+
+ /* Remove policy from list */
+ write_lock_irqsave(&cpufreq_driver_lock, flags);
+ list_del(&policy->policy_list);
+
+ for_each_cpu(cpu, policy->related_cpus)
+ per_cpu(cpufreq_cpu_data, cpu) = NULL;
+ write_unlock_irqrestore(&cpufreq_driver_lock, flags);
+
+ cpufreq_policy_put_kobj(policy);
+ free_cpumask_var(policy->real_cpus);
+ free_cpumask_var(policy->related_cpus);
+ free_cpumask_var(policy->cpus);
+ kfree(policy);
+}
+
+static int cpufreq_online(unsigned int cpu)
+{
+ struct cpufreq_policy *policy;
+ bool new_policy;
+ unsigned long flags;
+ unsigned int j;
+ int ret;
+
+ pr_debug("%s: bringing CPU%u online\n", __func__, cpu);
+
+ /* Check if this CPU already has a policy to manage it */
+ policy = per_cpu(cpufreq_cpu_data, cpu);
+ if (policy) {
+ WARN_ON(!cpumask_test_cpu(cpu, policy->related_cpus));
+ if (!policy_is_inactive(policy))
+ return cpufreq_add_policy_cpu(policy, cpu);
+
+ /* This is the only online CPU for the policy. Start over. */
+ new_policy = false;
+ down_write(&policy->rwsem);
+ policy->cpu = cpu;
+ policy->governor = NULL;
+ up_write(&policy->rwsem);
+ } else {
+ new_policy = true;
+ policy = cpufreq_policy_alloc(cpu);
+ if (!policy)
+ return -ENOMEM;
+ }
+
+ cpumask_copy(policy->cpus, cpumask_of(cpu));
+
+ /* call driver. From then on the cpufreq must be able
+ * to accept all calls to ->verify and ->setpolicy for this CPU
+ */
+ ret = cpufreq_driver->init(policy);
+ if (ret) {
+ pr_debug("initialization failed\n");
+ goto out_free_policy;
+ }
+
+ ret = cpufreq_table_validate_and_sort(policy);
+ if (ret)
+ goto out_exit_policy;
+
+ down_write(&policy->rwsem);
+
+ if (new_policy) {
+ /* related_cpus should at least include policy->cpus. */
+ cpumask_copy(policy->related_cpus, policy->cpus);
+ }
+
+ /*
+ * affected cpus must always be the one, which are online. We aren't
+ * managing offline cpus here.
+ */
+ cpumask_and(policy->cpus, policy->cpus, cpu_online_mask);
+
+ if (new_policy) {
+ policy->user_policy.min = policy->min;
+ policy->user_policy.max = policy->max;
+
+ for_each_cpu(j, policy->related_cpus) {
+ per_cpu(cpufreq_cpu_data, j) = policy;
+ add_cpu_dev_symlink(policy, j);
+ }
+ } else {
+ policy->min = policy->user_policy.min;
+ policy->max = policy->user_policy.max;
+ }
+
+ if (cpufreq_driver->get && !cpufreq_driver->setpolicy) {
+ policy->cur = cpufreq_driver->get(policy->cpu);
+ if (!policy->cur) {
+ pr_err("%s: ->get() failed\n", __func__);
+ goto out_destroy_policy;
+ }
+ }
+
+ /*
+ * Sometimes boot loaders set CPU frequency to a value outside of
+ * frequency table present with cpufreq core. In such cases CPU might be
+ * unstable if it has to run on that frequency for long duration of time
+ * and so its better to set it to a frequency which is specified in
+ * freq-table. This also makes cpufreq stats inconsistent as
+ * cpufreq-stats would fail to register because current frequency of CPU
+ * isn't found in freq-table.
+ *
+ * Because we don't want this change to effect boot process badly, we go
+ * for the next freq which is >= policy->cur ('cur' must be set by now,
+ * otherwise we will end up setting freq to lowest of the table as 'cur'
+ * is initialized to zero).
+ *
+ * We are passing target-freq as "policy->cur - 1" otherwise
+ * __cpufreq_driver_target() would simply fail, as policy->cur will be
+ * equal to target-freq.
+ */
+ if ((cpufreq_driver->flags & CPUFREQ_NEED_INITIAL_FREQ_CHECK)
+ && has_target()) {
+ /* Are we running at unknown frequency ? */
+ ret = cpufreq_frequency_table_get_index(policy, policy->cur);
+ if (ret == -EINVAL) {
+ /* Warn user and fix it */
+ pr_warn("%s: CPU%d: Running at unlisted freq: %u KHz\n",
+ __func__, policy->cpu, policy->cur);
+ ret = __cpufreq_driver_target(policy, policy->cur - 1,
+ CPUFREQ_RELATION_L);
+
+ /*
+ * Reaching here after boot in a few seconds may not
+ * mean that system will remain stable at "unknown"
+ * frequency for longer duration. Hence, a BUG_ON().
+ */
+ BUG_ON(ret);
+ pr_warn("%s: CPU%d: Unlisted initial frequency changed to: %u KHz\n",
+ __func__, policy->cpu, policy->cur);
+ }
+ }
+
+ if (new_policy) {
+ ret = cpufreq_add_dev_interface(policy);
+ if (ret)
+ goto out_destroy_policy;
+
+ cpufreq_stats_create_table(policy);
+
+ write_lock_irqsave(&cpufreq_driver_lock, flags);
+ list_add(&policy->policy_list, &cpufreq_policy_list);
+ write_unlock_irqrestore(&cpufreq_driver_lock, flags);
+ }
+
+ ret = cpufreq_init_policy(policy);
+ if (ret) {
+ pr_err("%s: Failed to initialize policy for cpu: %d (%d)\n",
+ __func__, cpu, ret);
+ /* cpufreq_policy_free() will notify based on this */
+ new_policy = false;
+ goto out_destroy_policy;
+ }
+
+ up_write(&policy->rwsem);
+
+ kobject_uevent(&policy->kobj, KOBJ_ADD);
+
+ /* Callback for handling stuff after policy is ready */
+ if (cpufreq_driver->ready)
+ cpufreq_driver->ready(policy);
+
+ pr_debug("initialization complete\n");
+
+ return 0;
+
+out_destroy_policy:
+ for_each_cpu(j, policy->real_cpus)
+ remove_cpu_dev_symlink(policy, get_cpu_device(j));
+
+ up_write(&policy->rwsem);
+
+out_exit_policy:
+ if (cpufreq_driver->exit)
+ cpufreq_driver->exit(policy);
+
+out_free_policy:
+ cpufreq_policy_free(policy);
+ return ret;
+}
+
+/**
+ * cpufreq_add_dev - the cpufreq interface for a CPU device.
+ * @dev: CPU device.
+ * @sif: Subsystem interface structure pointer (not used)
+ */
+static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif)
+{
+ struct cpufreq_policy *policy;
+ unsigned cpu = dev->id;
+ int ret;
+
+ dev_dbg(dev, "%s: adding CPU%u\n", __func__, cpu);
+
+ if (cpu_online(cpu)) {
+ ret = cpufreq_online(cpu);
+ if (ret)
+ return ret;
+ }
+
+ /* Create sysfs link on CPU registration */
+ policy = per_cpu(cpufreq_cpu_data, cpu);
+ if (policy)
+ add_cpu_dev_symlink(policy, cpu);
+
+ return 0;
+}
+
+static int cpufreq_offline(unsigned int cpu)
+{
+ struct cpufreq_policy *policy;
+ int ret;
+
+ pr_debug("%s: unregistering CPU %u\n", __func__, cpu);
+
+ policy = cpufreq_cpu_get_raw(cpu);
+ if (!policy) {
+ pr_debug("%s: No cpu_data found\n", __func__);
+ return 0;
+ }
+
+ down_write(&policy->rwsem);
+ if (has_target())
+ cpufreq_stop_governor(policy);
+
+ cpumask_clear_cpu(cpu, policy->cpus);
+
+ if (policy_is_inactive(policy)) {
+ if (has_target())
+ strncpy(policy->last_governor, policy->governor->name,
+ CPUFREQ_NAME_LEN);
+ else
+ policy->last_policy = policy->policy;
+ } else if (cpu == policy->cpu) {
+ /* Nominate new CPU */
+ policy->cpu = cpumask_any(policy->cpus);
+ }
+
+ /* Start governor again for active policy */
+ if (!policy_is_inactive(policy)) {
+ if (has_target()) {
+ ret = cpufreq_start_governor(policy);
+ if (ret)
+ pr_err("%s: Failed to start governor\n", __func__);
+ }
+
+ goto unlock;
+ }
+
+ if (cpufreq_driver->stop_cpu)
+ cpufreq_driver->stop_cpu(policy);
+
+ if (has_target())
+ cpufreq_exit_governor(policy);
+
+ /*
+ * Perform the ->exit() even during light-weight tear-down,
+ * since this is a core component, and is essential for the
+ * subsequent light-weight ->init() to succeed.
+ */
+ if (cpufreq_driver->exit) {
+ cpufreq_driver->exit(policy);
+ policy->freq_table = NULL;
+ }
+
+unlock:
+ up_write(&policy->rwsem);
+ return 0;
+}
+
+/**
+ * cpufreq_remove_dev - remove a CPU device
+ *
+ * Removes the cpufreq interface for a CPU device.
+ */
+static void cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif)
+{
+ unsigned int cpu = dev->id;
+ struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu);
+
+ if (!policy)
+ return;
+
+ if (cpu_online(cpu))
+ cpufreq_offline(cpu);
+
+ cpumask_clear_cpu(cpu, policy->real_cpus);
+ remove_cpu_dev_symlink(policy, dev);
+
+ if (cpumask_empty(policy->real_cpus))
+ cpufreq_policy_free(policy);
+}
+
+/**
+ * cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're
+ * in deep trouble.
+ * @policy: policy managing CPUs
+ * @new_freq: CPU frequency the CPU actually runs at
+ *
+ * We adjust to current frequency first, and need to clean up later.
+ * So either call to cpufreq_update_policy() or schedule handle_update()).
+ */
+static void cpufreq_out_of_sync(struct cpufreq_policy *policy,
+ unsigned int new_freq)
+{
+ struct cpufreq_freqs freqs;
+
+ pr_debug("Warning: CPU frequency out of sync: cpufreq and timing core thinks of %u, is %u kHz\n",
+ policy->cur, new_freq);
+
+ freqs.old = policy->cur;
+ freqs.new = new_freq;
+
+ cpufreq_freq_transition_begin(policy, &freqs);
+ cpufreq_freq_transition_end(policy, &freqs, 0);
+}
+
+/**
+ * cpufreq_quick_get - get the CPU frequency (in kHz) from policy->cur
+ * @cpu: CPU number
+ *
+ * This is the last known freq, without actually getting it from the driver.
+ * Return value will be same as what is shown in scaling_cur_freq in sysfs.
+ */
+unsigned int cpufreq_quick_get(unsigned int cpu)
+{
+ struct cpufreq_policy *policy;
+ unsigned int ret_freq = 0;
+ unsigned long flags;
+
+ read_lock_irqsave(&cpufreq_driver_lock, flags);
+
+ if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) {
+ ret_freq = cpufreq_driver->get(cpu);
+ read_unlock_irqrestore(&cpufreq_driver_lock, flags);
+ return ret_freq;
+ }
+
+ read_unlock_irqrestore(&cpufreq_driver_lock, flags);
+
+ policy = cpufreq_cpu_get(cpu);
+ if (policy) {
+ ret_freq = policy->cur;
+ cpufreq_cpu_put(policy);
+ }
+
+ return ret_freq;
+}
+EXPORT_SYMBOL(cpufreq_quick_get);
+
+/**
+ * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU
+ * @cpu: CPU number
+ *
+ * Just return the max possible frequency for a given CPU.
+ */
+unsigned int cpufreq_quick_get_max(unsigned int cpu)
+{
+ struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
+ unsigned int ret_freq = 0;
+
+ if (policy) {
+ ret_freq = policy->max;
+ cpufreq_cpu_put(policy);
+ }
+
+ return ret_freq;
+}
+EXPORT_SYMBOL(cpufreq_quick_get_max);
+
+static unsigned int __cpufreq_get(struct cpufreq_policy *policy)
+{
+ unsigned int ret_freq = 0;
+
+ if (!cpufreq_driver->get)
+ return ret_freq;
+
+ ret_freq = cpufreq_driver->get(policy->cpu);
+
+ /*
+ * Updating inactive policies is invalid, so avoid doing that. Also
+ * if fast frequency switching is used with the given policy, the check
+ * against policy->cur is pointless, so skip it in that case too.
+ */
+ if (unlikely(policy_is_inactive(policy)) || policy->fast_switch_enabled)
+ return ret_freq;
+
+ if (ret_freq && policy->cur &&
+ !(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) {
+ /* verify no discrepancy between actual and
+ saved value exists */
+ if (unlikely(ret_freq != policy->cur)) {
+ cpufreq_out_of_sync(policy, ret_freq);
+ schedule_work(&policy->update);
+ }
+ }
+
+ return ret_freq;
+}
+
+/**
+ * cpufreq_get - get the current CPU frequency (in kHz)
+ * @cpu: CPU number
+ *
+ * Get the CPU current (static) CPU frequency
+ */
+unsigned int cpufreq_get(unsigned int cpu)
+{
+ struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
+ unsigned int ret_freq = 0;
+
+ if (policy) {
+ down_read(&policy->rwsem);
+
+ if (!policy_is_inactive(policy))
+ ret_freq = __cpufreq_get(policy);
+
+ up_read(&policy->rwsem);
+
+ cpufreq_cpu_put(policy);
+ }
+
+ return ret_freq;
+}
+EXPORT_SYMBOL(cpufreq_get);
+
+static unsigned int cpufreq_update_current_freq(struct cpufreq_policy *policy)
+{
+ unsigned int new_freq;
+
+ new_freq = cpufreq_driver->get(policy->cpu);
+ if (!new_freq)
+ return 0;
+
+ if (!policy->cur) {
+ pr_debug("cpufreq: Driver did not initialize current freq\n");
+ policy->cur = new_freq;
+ } else if (policy->cur != new_freq && has_target()) {
+ cpufreq_out_of_sync(policy, new_freq);
+ }
+
+ return new_freq;
+}
+
+static struct subsys_interface cpufreq_interface = {
+ .name = "cpufreq",
+ .subsys = &cpu_subsys,
+ .add_dev = cpufreq_add_dev,
+ .remove_dev = cpufreq_remove_dev,
+};
+
+/*
+ * In case platform wants some specific frequency to be configured
+ * during suspend..
+ */
+int cpufreq_generic_suspend(struct cpufreq_policy *policy)
+{
+ int ret;
+
+ if (!policy->suspend_freq) {
+ pr_debug("%s: suspend_freq not defined\n", __func__);
+ return 0;
+ }
+
+ pr_debug("%s: Setting suspend-freq: %u\n", __func__,
+ policy->suspend_freq);
+
+ ret = __cpufreq_driver_target(policy, policy->suspend_freq,
+ CPUFREQ_RELATION_H);
+ if (ret)
+ pr_err("%s: unable to set suspend-freq: %u. err: %d\n",
+ __func__, policy->suspend_freq, ret);
+
+ return ret;
+}
+EXPORT_SYMBOL(cpufreq_generic_suspend);
+
+/**
+ * cpufreq_suspend() - Suspend CPUFreq governors
+ *
+ * Called during system wide Suspend/Hibernate cycles for suspending governors
+ * as some platforms can't change frequency after this point in suspend cycle.
+ * Because some of the devices (like: i2c, regulators, etc) they use for
+ * changing frequency are suspended quickly after this point.
+ */
+void cpufreq_suspend(void)
+{
+ struct cpufreq_policy *policy;
+
+ if (!cpufreq_driver)
+ return;
+
+ if (!has_target() && !cpufreq_driver->suspend)
+ goto suspend;
+
+ pr_debug("%s: Suspending Governors\n", __func__);
+
+ for_each_active_policy(policy) {
+ if (has_target()) {
+ down_write(&policy->rwsem);
+ cpufreq_stop_governor(policy);
+ up_write(&policy->rwsem);
+ }
+
+ if (cpufreq_driver->suspend && cpufreq_driver->suspend(policy))
+ pr_err("%s: Failed to suspend driver: %p\n", __func__,
+ policy);
+ }
+
+suspend:
+ cpufreq_suspended = true;
+}
+
+/**
+ * cpufreq_resume() - Resume CPUFreq governors
+ *
+ * Called during system wide Suspend/Hibernate cycle for resuming governors that
+ * are suspended with cpufreq_suspend().
+ */
+void cpufreq_resume(void)
+{
+ struct cpufreq_policy *policy;
+ int ret;
+
+ if (!cpufreq_driver)
+ return;
+
+ if (unlikely(!cpufreq_suspended))
+ return;
+
+ cpufreq_suspended = false;
+
+ if (!has_target() && !cpufreq_driver->resume)
+ return;
+
+ pr_debug("%s: Resuming Governors\n", __func__);
+
+ for_each_active_policy(policy) {
+ if (cpufreq_driver->resume && cpufreq_driver->resume(policy)) {
+ pr_err("%s: Failed to resume driver: %p\n", __func__,
+ policy);
+ } else if (has_target()) {
+ down_write(&policy->rwsem);
+ ret = cpufreq_start_governor(policy);
+ up_write(&policy->rwsem);
+
+ if (ret)
+ pr_err("%s: Failed to start governor for policy: %p\n",
+ __func__, policy);
+ }
+ }
+}
+
+/**
+ * cpufreq_get_current_driver - return current driver's name
+ *
+ * Return the name string of the currently loaded cpufreq driver
+ * or NULL, if none.
+ */
+const char *cpufreq_get_current_driver(void)
+{
+ if (cpufreq_driver)
+ return cpufreq_driver->name;
+
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(cpufreq_get_current_driver);
+
+/**
+ * cpufreq_get_driver_data - return current driver data
+ *
+ * Return the private data of the currently loaded cpufreq
+ * driver, or NULL if no cpufreq driver is loaded.
+ */
+void *cpufreq_get_driver_data(void)
+{
+ if (cpufreq_driver)
+ return cpufreq_driver->driver_data;
+
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(cpufreq_get_driver_data);
+
+/*********************************************************************
+ * NOTIFIER LISTS INTERFACE *
+ *********************************************************************/
+
+/**
+ * cpufreq_register_notifier - register a driver with cpufreq
+ * @nb: notifier function to register
+ * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER
+ *
+ * Add a driver to one of two lists: either a list of drivers that
+ * are notified about clock rate changes (once before and once after
+ * the transition), or a list of drivers that are notified about
+ * changes in cpufreq policy.
+ *
+ * This function may sleep, and has the same return conditions as
+ * blocking_notifier_chain_register.
+ */
+int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list)
+{
+ int ret;
+
+ if (cpufreq_disabled())
+ return -EINVAL;
+
+ switch (list) {
+ case CPUFREQ_TRANSITION_NOTIFIER:
+ mutex_lock(&cpufreq_fast_switch_lock);
+
+ if (cpufreq_fast_switch_count > 0) {
+ mutex_unlock(&cpufreq_fast_switch_lock);
+ return -EBUSY;
+ }
+ ret = srcu_notifier_chain_register(
+ &cpufreq_transition_notifier_list, nb);
+ if (!ret)
+ cpufreq_fast_switch_count--;
+
+ mutex_unlock(&cpufreq_fast_switch_lock);
+ break;
+ case CPUFREQ_POLICY_NOTIFIER:
+ ret = blocking_notifier_chain_register(
+ &cpufreq_policy_notifier_list, nb);
+ break;
+ default:
+ ret = -EINVAL;
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL(cpufreq_register_notifier);
+
+/**
+ * cpufreq_unregister_notifier - unregister a driver with cpufreq
+ * @nb: notifier block to be unregistered
+ * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER
+ *
+ * Remove a driver from the CPU frequency notifier list.
+ *
+ * This function may sleep, and has the same return conditions as
+ * blocking_notifier_chain_unregister.
+ */
+int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list)
+{
+ int ret;
+
+ if (cpufreq_disabled())
+ return -EINVAL;
+
+ switch (list) {
+ case CPUFREQ_TRANSITION_NOTIFIER:
+ mutex_lock(&cpufreq_fast_switch_lock);
+
+ ret = srcu_notifier_chain_unregister(
+ &cpufreq_transition_notifier_list, nb);
+ if (!ret && !WARN_ON(cpufreq_fast_switch_count >= 0))
+ cpufreq_fast_switch_count++;
+
+ mutex_unlock(&cpufreq_fast_switch_lock);
+ break;
+ case CPUFREQ_POLICY_NOTIFIER:
+ ret = blocking_notifier_chain_unregister(
+ &cpufreq_policy_notifier_list, nb);
+ break;
+ default:
+ ret = -EINVAL;
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL(cpufreq_unregister_notifier);
+
+
+/*********************************************************************
+ * GOVERNORS *
+ *********************************************************************/
+
+/**
+ * cpufreq_driver_fast_switch - Carry out a fast CPU frequency switch.
+ * @policy: cpufreq policy to switch the frequency for.
+ * @target_freq: New frequency to set (may be approximate).
+ *
+ * Carry out a fast frequency switch without sleeping.
+ *
+ * The driver's ->fast_switch() callback invoked by this function must be
+ * suitable for being called from within RCU-sched read-side critical sections
+ * and it is expected to select the minimum available frequency greater than or
+ * equal to @target_freq (CPUFREQ_RELATION_L).
+ *
+ * This function must not be called if policy->fast_switch_enabled is unset.
+ *
+ * Governors calling this function must guarantee that it will never be invoked
+ * twice in parallel for the same policy and that it will never be called in
+ * parallel with either ->target() or ->target_index() for the same policy.
+ *
+ * Returns the actual frequency set for the CPU.
+ *
+ * If 0 is returned by the driver's ->fast_switch() callback to indicate an
+ * error condition, the hardware configuration must be preserved.
+ */
+unsigned int cpufreq_driver_fast_switch(struct cpufreq_policy *policy,
+ unsigned int target_freq)
+{
+ target_freq = clamp_val(target_freq, policy->min, policy->max);
+
+ return cpufreq_driver->fast_switch(policy, target_freq);
+}
+EXPORT_SYMBOL_GPL(cpufreq_driver_fast_switch);
+
+/* Must set freqs->new to intermediate frequency */
+static int __target_intermediate(struct cpufreq_policy *policy,
+ struct cpufreq_freqs *freqs, int index)
+{
+ int ret;
+
+ freqs->new = cpufreq_driver->get_intermediate(policy, index);
+
+ /* We don't need to switch to intermediate freq */
+ if (!freqs->new)
+ return 0;
+
+ pr_debug("%s: cpu: %d, switching to intermediate freq: oldfreq: %u, intermediate freq: %u\n",
+ __func__, policy->cpu, freqs->old, freqs->new);
+
+ cpufreq_freq_transition_begin(policy, freqs);
+ ret = cpufreq_driver->target_intermediate(policy, index);
+ cpufreq_freq_transition_end(policy, freqs, ret);
+
+ if (ret)
+ pr_err("%s: Failed to change to intermediate frequency: %d\n",
+ __func__, ret);
+
+ return ret;
+}
+
+static int __target_index(struct cpufreq_policy *policy, int index)
+{
+ struct cpufreq_freqs freqs = {.old = policy->cur, .flags = 0};
+ unsigned int intermediate_freq = 0;
+ unsigned int newfreq = policy->freq_table[index].frequency;
+ int retval = -EINVAL;
+ bool notify;
+
+ if (newfreq == policy->cur)
+ return 0;
+
+ notify = !(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION);
+ if (notify) {
+ /* Handle switching to intermediate frequency */
+ if (cpufreq_driver->get_intermediate) {
+ retval = __target_intermediate(policy, &freqs, index);
+ if (retval)
+ return retval;
+
+ intermediate_freq = freqs.new;
+ /* Set old freq to intermediate */
+ if (intermediate_freq)
+ freqs.old = freqs.new;
+ }
+
+ freqs.new = newfreq;
+ pr_debug("%s: cpu: %d, oldfreq: %u, new freq: %u\n",
+ __func__, policy->cpu, freqs.old, freqs.new);
+
+ cpufreq_freq_transition_begin(policy, &freqs);
+ }
+
+ retval = cpufreq_driver->target_index(policy, index);
+ if (retval)
+ pr_err("%s: Failed to change cpu frequency: %d\n", __func__,
+ retval);
+
+ if (notify) {
+ cpufreq_freq_transition_end(policy, &freqs, retval);
+
+ /*
+ * Failed after setting to intermediate freq? Driver should have
+ * reverted back to initial frequency and so should we. Check
+ * here for intermediate_freq instead of get_intermediate, in
+ * case we haven't switched to intermediate freq at all.
+ */
+ if (unlikely(retval && intermediate_freq)) {
+ freqs.old = intermediate_freq;
+ freqs.new = policy->restore_freq;
+ cpufreq_freq_transition_begin(policy, &freqs);
+ cpufreq_freq_transition_end(policy, &freqs, 0);
+ }
+ }
+
+ return retval;
+}
+
+int __cpufreq_driver_target(struct cpufreq_policy *policy,
+ unsigned int target_freq,
+ unsigned int relation)
+{
+ unsigned int old_target_freq = target_freq;
+ int index;
+
+ if (cpufreq_disabled())
+ return -ENODEV;
+
+ /* Make sure that target_freq is within supported range */
+ target_freq = clamp_val(target_freq, policy->min, policy->max);
+
+ pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n",
+ policy->cpu, target_freq, relation, old_target_freq);
+
+ /*
+ * This might look like a redundant call as we are checking it again
+ * after finding index. But it is left intentionally for cases where
+ * exactly same freq is called again and so we can save on few function
+ * calls.
+ */
+ if (target_freq == policy->cur)
+ return 0;
+
+ /* Save last value to restore later on errors */
+ policy->restore_freq = policy->cur;
+
+ if (cpufreq_driver->target)
+ return cpufreq_driver->target(policy, target_freq, relation);
+
+ if (!cpufreq_driver->target_index)
+ return -EINVAL;
+
+ index = cpufreq_frequency_table_target(policy, target_freq, relation);
+
+ return __target_index(policy, index);
+}
+EXPORT_SYMBOL_GPL(__cpufreq_driver_target);
+
+int cpufreq_driver_target(struct cpufreq_policy *policy,
+ unsigned int target_freq,
+ unsigned int relation)
+{
+ int ret = -EINVAL;
+
+ down_write(&policy->rwsem);
+
+ ret = __cpufreq_driver_target(policy, target_freq, relation);
+
+ up_write(&policy->rwsem);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(cpufreq_driver_target);
+
+__weak struct cpufreq_governor *cpufreq_fallback_governor(void)
+{
+ return NULL;
+}
+
+static int cpufreq_init_governor(struct cpufreq_policy *policy)
+{
+ int ret;
+
+ /* Don't start any governor operations if we are entering suspend */
+ if (cpufreq_suspended)
+ return 0;
+ /*
+ * Governor might not be initiated here if ACPI _PPC changed
+ * notification happened, so check it.
+ */
+ if (!policy->governor)
+ return -EINVAL;
+
+ /* Platform doesn't want dynamic frequency switching ? */
+ if (policy->governor->dynamic_switching &&
+ cpufreq_driver->flags & CPUFREQ_NO_AUTO_DYNAMIC_SWITCHING) {
+ struct cpufreq_governor *gov = cpufreq_fallback_governor();
+
+ if (gov) {
+ pr_warn("Can't use %s governor as dynamic switching is disallowed. Fallback to %s governor\n",
+ policy->governor->name, gov->name);
+ policy->governor = gov;
+ } else {
+ return -EINVAL;
+ }
+ }
+
+ if (!try_module_get(policy->governor->owner))
+ return -EINVAL;
+
+ pr_debug("%s: for CPU %u\n", __func__, policy->cpu);
+
+ if (policy->governor->init) {
+ ret = policy->governor->init(policy);
+ if (ret) {
+ module_put(policy->governor->owner);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static void cpufreq_exit_governor(struct cpufreq_policy *policy)
+{
+ if (cpufreq_suspended || !policy->governor)
+ return;
+
+ pr_debug("%s: for CPU %u\n", __func__, policy->cpu);
+
+ if (policy->governor->exit)
+ policy->governor->exit(policy);
+
+ module_put(policy->governor->owner);
+}
+
+static int cpufreq_start_governor(struct cpufreq_policy *policy)
+{
+ int ret;
+
+ if (cpufreq_suspended)
+ return 0;
+
+ if (!policy->governor)
+ return -EINVAL;
+
+ pr_debug("%s: for CPU %u\n", __func__, policy->cpu);
+
+ if (cpufreq_driver->get && !cpufreq_driver->setpolicy)
+ cpufreq_update_current_freq(policy);
+
+ if (policy->governor->start) {
+ ret = policy->governor->start(policy);
+ if (ret)
+ return ret;
+ }
+
+ if (policy->governor->limits)
+ policy->governor->limits(policy);
+
+ return 0;
+}
+
+static void cpufreq_stop_governor(struct cpufreq_policy *policy)
+{
+ if (cpufreq_suspended || !policy->governor)
+ return;
+
+ pr_debug("%s: for CPU %u\n", __func__, policy->cpu);
+
+ if (policy->governor->stop)
+ policy->governor->stop(policy);
+}
+
+static void cpufreq_governor_limits(struct cpufreq_policy *policy)
+{
+ if (cpufreq_suspended || !policy->governor)
+ return;
+
+ pr_debug("%s: for CPU %u\n", __func__, policy->cpu);
+
+ if (policy->governor->limits)
+ policy->governor->limits(policy);
+}
+
+int cpufreq_register_governor(struct cpufreq_governor *governor)
+{
+ int err;
+
+ if (!governor)
+ return -EINVAL;
+
+ if (cpufreq_disabled())
+ return -ENODEV;
+
+ mutex_lock(&cpufreq_governor_mutex);
+
+ err = -EBUSY;
+ if (!find_governor(governor->name)) {
+ err = 0;
+ list_add(&governor->governor_list, &cpufreq_governor_list);
+ }
+
+ mutex_unlock(&cpufreq_governor_mutex);
+ return err;
+}
+EXPORT_SYMBOL_GPL(cpufreq_register_governor);
+
+void cpufreq_unregister_governor(struct cpufreq_governor *governor)
+{
+ struct cpufreq_policy *policy;
+ unsigned long flags;
+
+ if (!governor)
+ return;
+
+ if (cpufreq_disabled())
+ return;
+
+ /* clear last_governor for all inactive policies */
+ read_lock_irqsave(&cpufreq_driver_lock, flags);
+ for_each_inactive_policy(policy) {
+ if (!strcmp(policy->last_governor, governor->name)) {
+ policy->governor = NULL;
+ strcpy(policy->last_governor, "\0");
+ }
+ }
+ read_unlock_irqrestore(&cpufreq_driver_lock, flags);
+
+ mutex_lock(&cpufreq_governor_mutex);
+ list_del(&governor->governor_list);
+ mutex_unlock(&cpufreq_governor_mutex);
+}
+EXPORT_SYMBOL_GPL(cpufreq_unregister_governor);
+
+
+/*********************************************************************
+ * POLICY INTERFACE *
+ *********************************************************************/
+
+/**
+ * cpufreq_get_policy - get the current cpufreq_policy
+ * @policy: struct cpufreq_policy into which the current cpufreq_policy
+ * is written
+ *
+ * Reads the current cpufreq policy.
+ */
+int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu)
+{
+ struct cpufreq_policy *cpu_policy;
+ if (!policy)
+ return -EINVAL;
+
+ cpu_policy = cpufreq_cpu_get(cpu);
+ if (!cpu_policy)
+ return -EINVAL;
+
+ memcpy(policy, cpu_policy, sizeof(*policy));
+
+ cpufreq_cpu_put(cpu_policy);
+ return 0;
+}
+EXPORT_SYMBOL(cpufreq_get_policy);
+
+/*
+ * policy : current policy.
+ * new_policy: policy to be set.
+ */
+static int cpufreq_set_policy(struct cpufreq_policy *policy,
+ struct cpufreq_policy *new_policy)
+{
+ struct cpufreq_governor *old_gov;
+ int ret;
+
+ pr_debug("setting new policy for CPU %u: %u - %u kHz\n",
+ new_policy->cpu, new_policy->min, new_policy->max);
+
+ memcpy(&new_policy->cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo));
+
+ /*
+ * This check works well when we store new min/max freq attributes,
+ * because new_policy is a copy of policy with one field updated.
+ */
+ if (new_policy->min > new_policy->max)
+ return -EINVAL;
+
+ /* verify the cpu speed can be set within this limit */
+ ret = cpufreq_driver->verify(new_policy);
+ if (ret)
+ return ret;
+
+ /* adjust if necessary - all reasons */
+ blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
+ CPUFREQ_ADJUST, new_policy);
+
+ /*
+ * verify the cpu speed can be set within this limit, which might be
+ * different to the first one
+ */
+ ret = cpufreq_driver->verify(new_policy);
+ if (ret)
+ return ret;
+
+ /* notification of the new policy */
+ blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
+ CPUFREQ_NOTIFY, new_policy);
+
+ policy->min = new_policy->min;
+ policy->max = new_policy->max;
+ trace_cpu_frequency_limits(policy);
+
+ policy->cached_target_freq = UINT_MAX;
+
+ pr_debug("new min and max freqs are %u - %u kHz\n",
+ policy->min, policy->max);
+
+ if (cpufreq_driver->setpolicy) {
+ policy->policy = new_policy->policy;
+ pr_debug("setting range\n");
+ return cpufreq_driver->setpolicy(new_policy);
+ }
+
+ if (new_policy->governor == policy->governor) {
+ pr_debug("cpufreq: governor limits update\n");
+ cpufreq_governor_limits(policy);
+ return 0;
+ }
+
+ pr_debug("governor switch\n");
+
+ /* save old, working values */
+ old_gov = policy->governor;
+ /* end old governor */
+ if (old_gov) {
+ cpufreq_stop_governor(policy);
+ cpufreq_exit_governor(policy);
+ }
+
+ /* start new governor */
+ policy->governor = new_policy->governor;
+ ret = cpufreq_init_governor(policy);
+ if (!ret) {
+ ret = cpufreq_start_governor(policy);
+ if (!ret) {
+ pr_debug("cpufreq: governor change\n");
+ return 0;
+ }
+ cpufreq_exit_governor(policy);
+ }
+
+ /* new governor failed, so re-start old one */
+ pr_debug("starting governor %s failed\n", policy->governor->name);
+ if (old_gov) {
+ policy->governor = old_gov;
+ if (cpufreq_init_governor(policy))
+ policy->governor = NULL;
+ else
+ cpufreq_start_governor(policy);
+ }
+
+ return ret;
+}
+
+/**
+ * cpufreq_update_policy - re-evaluate an existing cpufreq policy
+ * @cpu: CPU which shall be re-evaluated
+ *
+ * Useful for policy notifiers which have different necessities
+ * at different times.
+ */
+void cpufreq_update_policy(unsigned int cpu)
+{
+ struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
+ struct cpufreq_policy new_policy;
+
+ if (!policy)
+ return;
+
+ down_write(&policy->rwsem);
+
+ if (policy_is_inactive(policy))
+ goto unlock;
+
+ pr_debug("updating policy for CPU %u\n", cpu);
+ memcpy(&new_policy, policy, sizeof(*policy));
+ new_policy.min = policy->user_policy.min;
+ new_policy.max = policy->user_policy.max;
+
+ /*
+ * BIOS might change freq behind our back
+ * -> ask driver for current freq and notify governors about a change
+ */
+ if (cpufreq_driver->get && !cpufreq_driver->setpolicy) {
+ if (cpufreq_suspended)
+ goto unlock;
+
+ new_policy.cur = cpufreq_update_current_freq(policy);
+ if (WARN_ON(!new_policy.cur))
+ goto unlock;
+ }
+
+ cpufreq_set_policy(policy, &new_policy);
+
+unlock:
+ up_write(&policy->rwsem);
+
+ cpufreq_cpu_put(policy);
+}
+EXPORT_SYMBOL(cpufreq_update_policy);
+
+/*********************************************************************
+ * BOOST *
+ *********************************************************************/
+static int cpufreq_boost_set_sw(int state)
+{
+ struct cpufreq_policy *policy;
+ int ret = -EINVAL;
+
+ for_each_active_policy(policy) {
+ if (!policy->freq_table)
+ continue;
+
+ ret = cpufreq_frequency_table_cpuinfo(policy,
+ policy->freq_table);
+ if (ret) {
+ pr_err("%s: Policy frequency update failed\n",
+ __func__);
+ break;
+ }
+
+ down_write(&policy->rwsem);
+ policy->user_policy.max = policy->max;
+ cpufreq_governor_limits(policy);
+ up_write(&policy->rwsem);
+ }
+
+ return ret;
+}
+
+int cpufreq_boost_trigger_state(int state)
+{
+ unsigned long flags;
+ int ret = 0;
+
+ if (cpufreq_driver->boost_enabled == state)
+ return 0;
+
+ write_lock_irqsave(&cpufreq_driver_lock, flags);
+ cpufreq_driver->boost_enabled = state;
+ write_unlock_irqrestore(&cpufreq_driver_lock, flags);
+
+ ret = cpufreq_driver->set_boost(state);
+ if (ret) {
+ write_lock_irqsave(&cpufreq_driver_lock, flags);
+ cpufreq_driver->boost_enabled = !state;
+ write_unlock_irqrestore(&cpufreq_driver_lock, flags);
+
+ pr_err("%s: Cannot %s BOOST\n",
+ __func__, state ? "enable" : "disable");
+ }
+
+ return ret;
+}
+
+static bool cpufreq_boost_supported(void)
+{
+ return likely(cpufreq_driver) && cpufreq_driver->set_boost;
+}
+
+static int create_boost_sysfs_file(void)
+{
+ int ret;
+
+ ret = sysfs_create_file(cpufreq_global_kobject, &boost.attr);
+ if (ret)
+ pr_err("%s: cannot register global BOOST sysfs file\n",
+ __func__);
+
+ return ret;
+}
+
+static void remove_boost_sysfs_file(void)
+{
+ if (cpufreq_boost_supported())
+ sysfs_remove_file(cpufreq_global_kobject, &boost.attr);
+}
+
+int cpufreq_enable_boost_support(void)
+{
+ if (!cpufreq_driver)
+ return -EINVAL;
+
+ if (cpufreq_boost_supported())
+ return 0;
+
+ cpufreq_driver->set_boost = cpufreq_boost_set_sw;
+
+ /* This will get removed on driver unregister */
+ return create_boost_sysfs_file();
+}
+EXPORT_SYMBOL_GPL(cpufreq_enable_boost_support);
+
+int cpufreq_boost_enabled(void)
+{
+ return cpufreq_driver->boost_enabled;
+}
+EXPORT_SYMBOL_GPL(cpufreq_boost_enabled);
+
+/*********************************************************************
+ * REGISTER / UNREGISTER CPUFREQ DRIVER *
+ *********************************************************************/
+static enum cpuhp_state hp_online;
+
+static int cpuhp_cpufreq_online(unsigned int cpu)
+{
+ cpufreq_online(cpu);
+
+ return 0;
+}
+
+static int cpuhp_cpufreq_offline(unsigned int cpu)
+{
+ cpufreq_offline(cpu);
+
+ return 0;
+}
+
+/**
+ * cpufreq_register_driver - register a CPU Frequency driver
+ * @driver_data: A struct cpufreq_driver containing the values#
+ * submitted by the CPU Frequency driver.
+ *
+ * Registers a CPU Frequency driver to this core code. This code
+ * returns zero on success, -EEXIST when another driver got here first
+ * (and isn't unregistered in the meantime).
+ *
+ */
+int cpufreq_register_driver(struct cpufreq_driver *driver_data)
+{
+ unsigned long flags;
+ int ret;
+
+ if (cpufreq_disabled())
+ return -ENODEV;
+
+ if (!driver_data || !driver_data->verify || !driver_data->init ||
+ !(driver_data->setpolicy || driver_data->target_index ||
+ driver_data->target) ||
+ (driver_data->setpolicy && (driver_data->target_index ||
+ driver_data->target)) ||
+ (!!driver_data->get_intermediate != !!driver_data->target_intermediate))
+ return -EINVAL;
+
+ pr_debug("trying to register driver %s\n", driver_data->name);
+
+ /* Protect against concurrent CPU online/offline. */
+ cpus_read_lock();
+
+ write_lock_irqsave(&cpufreq_driver_lock, flags);
+ if (cpufreq_driver) {
+ write_unlock_irqrestore(&cpufreq_driver_lock, flags);
+ ret = -EEXIST;
+ goto out;
+ }
+ cpufreq_driver = driver_data;
+ write_unlock_irqrestore(&cpufreq_driver_lock, flags);
+
+ if (driver_data->setpolicy)
+ driver_data->flags |= CPUFREQ_CONST_LOOPS;
+
+ if (cpufreq_boost_supported()) {
+ ret = create_boost_sysfs_file();
+ if (ret)
+ goto err_null_driver;
+ }
+
+ ret = subsys_interface_register(&cpufreq_interface);
+ if (ret)
+ goto err_boost_unreg;
+
+ if (!(cpufreq_driver->flags & CPUFREQ_STICKY) &&
+ list_empty(&cpufreq_policy_list)) {
+ /* if all ->init() calls failed, unregister */
+ ret = -ENODEV;
+ pr_debug("%s: No CPU initialized for driver %s\n", __func__,
+ driver_data->name);
+ goto err_if_unreg;
+ }
+
+ ret = cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ONLINE_DYN,
+ "cpufreq:online",
+ cpuhp_cpufreq_online,
+ cpuhp_cpufreq_offline);
+ if (ret < 0)
+ goto err_if_unreg;
+ hp_online = ret;
+ ret = 0;
+
+ pr_debug("driver %s up and running\n", driver_data->name);
+ goto out;
+
+err_if_unreg:
+ subsys_interface_unregister(&cpufreq_interface);
+err_boost_unreg:
+ remove_boost_sysfs_file();
+err_null_driver:
+ write_lock_irqsave(&cpufreq_driver_lock, flags);
+ cpufreq_driver = NULL;
+ write_unlock_irqrestore(&cpufreq_driver_lock, flags);
+out:
+ cpus_read_unlock();
+ return ret;
+}
+EXPORT_SYMBOL_GPL(cpufreq_register_driver);
+
+/**
+ * cpufreq_unregister_driver - unregister the current CPUFreq driver
+ *
+ * Unregister the current CPUFreq driver. Only call this if you have
+ * the right to do so, i.e. if you have succeeded in initialising before!
+ * Returns zero if successful, and -EINVAL if the cpufreq_driver is
+ * currently not initialised.
+ */
+int cpufreq_unregister_driver(struct cpufreq_driver *driver)
+{
+ unsigned long flags;
+
+ if (!cpufreq_driver || (driver != cpufreq_driver))
+ return -EINVAL;
+
+ pr_debug("unregistering driver %s\n", driver->name);
+
+ /* Protect against concurrent cpu hotplug */
+ cpus_read_lock();
+ subsys_interface_unregister(&cpufreq_interface);
+ remove_boost_sysfs_file();
+ cpuhp_remove_state_nocalls_cpuslocked(hp_online);
+
+ write_lock_irqsave(&cpufreq_driver_lock, flags);
+
+ cpufreq_driver = NULL;
+
+ write_unlock_irqrestore(&cpufreq_driver_lock, flags);
+ cpus_read_unlock();
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(cpufreq_unregister_driver);
+
+/*
+ * Stop cpufreq at shutdown to make sure it isn't holding any locks
+ * or mutexes when secondary CPUs are halted.
+ */
+static struct syscore_ops cpufreq_syscore_ops = {
+ .shutdown = cpufreq_suspend,
+};
+
+struct kobject *cpufreq_global_kobject;
+EXPORT_SYMBOL(cpufreq_global_kobject);
+
+static int __init cpufreq_core_init(void)
+{
+ if (cpufreq_disabled())
+ return -ENODEV;
+
+ cpufreq_global_kobject = kobject_create_and_add("cpufreq", &cpu_subsys.dev_root->kobj);
+ BUG_ON(!cpufreq_global_kobject);
+
+ register_syscore_ops(&cpufreq_syscore_ops);
+
+ return 0;
+}
+module_param(off, int, 0444);
+core_initcall(cpufreq_core_init);