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![Viresh Kumar](/assets/img/avatar_default.png)
This isn't used anymore, get rid of it. Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2908 lines
75 KiB
C
2908 lines
75 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* linux/drivers/cpufreq/cpufreq.c
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*
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* Copyright (C) 2001 Russell King
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* (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de>
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* (C) 2013 Viresh Kumar <viresh.kumar@linaro.org>
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*
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* Oct 2005 - Ashok Raj <ashok.raj@intel.com>
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* Added handling for CPU hotplug
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* Feb 2006 - Jacob Shin <jacob.shin@amd.com>
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* Fix handling for CPU hotplug -- affected CPUs
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/cpu.h>
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#include <linux/cpufreq.h>
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#include <linux/cpu_cooling.h>
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#include <linux/delay.h>
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#include <linux/device.h>
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#include <linux/init.h>
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#include <linux/kernel_stat.h>
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#include <linux/module.h>
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#include <linux/mutex.h>
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#include <linux/pm_qos.h>
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#include <linux/slab.h>
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#include <linux/suspend.h>
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#include <linux/syscore_ops.h>
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#include <linux/tick.h>
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#include <trace/events/power.h>
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static LIST_HEAD(cpufreq_policy_list);
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/* Macros to iterate over CPU policies */
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#define for_each_suitable_policy(__policy, __active) \
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list_for_each_entry(__policy, &cpufreq_policy_list, policy_list) \
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if ((__active) == !policy_is_inactive(__policy))
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#define for_each_active_policy(__policy) \
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for_each_suitable_policy(__policy, true)
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#define for_each_inactive_policy(__policy) \
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for_each_suitable_policy(__policy, false)
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/* Iterate over governors */
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static LIST_HEAD(cpufreq_governor_list);
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#define for_each_governor(__governor) \
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list_for_each_entry(__governor, &cpufreq_governor_list, governor_list)
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static char default_governor[CPUFREQ_NAME_LEN];
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/*
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* The "cpufreq driver" - the arch- or hardware-dependent low
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* level driver of CPUFreq support, and its spinlock. This lock
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* also protects the cpufreq_cpu_data array.
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*/
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static struct cpufreq_driver *cpufreq_driver;
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static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data);
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static DEFINE_RWLOCK(cpufreq_driver_lock);
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static DEFINE_STATIC_KEY_FALSE(cpufreq_freq_invariance);
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bool cpufreq_supports_freq_invariance(void)
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{
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return static_branch_likely(&cpufreq_freq_invariance);
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}
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/* Flag to suspend/resume CPUFreq governors */
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static bool cpufreq_suspended;
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static inline bool has_target(void)
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{
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return cpufreq_driver->target_index || cpufreq_driver->target;
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}
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/* internal prototypes */
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static unsigned int __cpufreq_get(struct cpufreq_policy *policy);
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static int cpufreq_init_governor(struct cpufreq_policy *policy);
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static void cpufreq_exit_governor(struct cpufreq_policy *policy);
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static void cpufreq_governor_limits(struct cpufreq_policy *policy);
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static int cpufreq_set_policy(struct cpufreq_policy *policy,
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struct cpufreq_governor *new_gov,
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unsigned int new_pol);
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/*
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* Two notifier lists: the "policy" list is involved in the
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* validation process for a new CPU frequency policy; the
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* "transition" list for kernel code that needs to handle
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* changes to devices when the CPU clock speed changes.
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* The mutex locks both lists.
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*/
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static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list);
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SRCU_NOTIFIER_HEAD_STATIC(cpufreq_transition_notifier_list);
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static int off __read_mostly;
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static int cpufreq_disabled(void)
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{
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return off;
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}
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void disable_cpufreq(void)
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{
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off = 1;
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}
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static DEFINE_MUTEX(cpufreq_governor_mutex);
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bool have_governor_per_policy(void)
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{
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return !!(cpufreq_driver->flags & CPUFREQ_HAVE_GOVERNOR_PER_POLICY);
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}
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EXPORT_SYMBOL_GPL(have_governor_per_policy);
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static struct kobject *cpufreq_global_kobject;
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struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy)
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{
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if (have_governor_per_policy())
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return &policy->kobj;
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else
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return cpufreq_global_kobject;
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}
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EXPORT_SYMBOL_GPL(get_governor_parent_kobj);
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static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall)
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{
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struct kernel_cpustat kcpustat;
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u64 cur_wall_time;
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u64 idle_time;
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u64 busy_time;
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cur_wall_time = jiffies64_to_nsecs(get_jiffies_64());
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kcpustat_cpu_fetch(&kcpustat, cpu);
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busy_time = kcpustat.cpustat[CPUTIME_USER];
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busy_time += kcpustat.cpustat[CPUTIME_SYSTEM];
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busy_time += kcpustat.cpustat[CPUTIME_IRQ];
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busy_time += kcpustat.cpustat[CPUTIME_SOFTIRQ];
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busy_time += kcpustat.cpustat[CPUTIME_STEAL];
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busy_time += kcpustat.cpustat[CPUTIME_NICE];
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idle_time = cur_wall_time - busy_time;
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if (wall)
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*wall = div_u64(cur_wall_time, NSEC_PER_USEC);
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return div_u64(idle_time, NSEC_PER_USEC);
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}
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u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy)
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{
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u64 idle_time = get_cpu_idle_time_us(cpu, io_busy ? wall : NULL);
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if (idle_time == -1ULL)
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return get_cpu_idle_time_jiffy(cpu, wall);
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else if (!io_busy)
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idle_time += get_cpu_iowait_time_us(cpu, wall);
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return idle_time;
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}
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EXPORT_SYMBOL_GPL(get_cpu_idle_time);
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/*
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* This is a generic cpufreq init() routine which can be used by cpufreq
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* drivers of SMP systems. It will do following:
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* - validate & show freq table passed
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* - set policies transition latency
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* - policy->cpus with all possible CPUs
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*/
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void cpufreq_generic_init(struct cpufreq_policy *policy,
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struct cpufreq_frequency_table *table,
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unsigned int transition_latency)
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{
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policy->freq_table = table;
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policy->cpuinfo.transition_latency = transition_latency;
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/*
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* The driver only supports the SMP configuration where all processors
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* share the clock and voltage and clock.
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*/
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cpumask_setall(policy->cpus);
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}
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EXPORT_SYMBOL_GPL(cpufreq_generic_init);
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struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu)
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{
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struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu);
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return policy && cpumask_test_cpu(cpu, policy->cpus) ? policy : NULL;
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}
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EXPORT_SYMBOL_GPL(cpufreq_cpu_get_raw);
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unsigned int cpufreq_generic_get(unsigned int cpu)
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{
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struct cpufreq_policy *policy = cpufreq_cpu_get_raw(cpu);
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if (!policy || IS_ERR(policy->clk)) {
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pr_err("%s: No %s associated to cpu: %d\n",
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__func__, policy ? "clk" : "policy", cpu);
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return 0;
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}
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return clk_get_rate(policy->clk) / 1000;
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}
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EXPORT_SYMBOL_GPL(cpufreq_generic_get);
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/**
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* cpufreq_cpu_get - Return policy for a CPU and mark it as busy.
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* @cpu: CPU to find the policy for.
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*
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* Call cpufreq_cpu_get_raw() to obtain a cpufreq policy for @cpu and increment
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* the kobject reference counter of that policy. Return a valid policy on
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* success or NULL on failure.
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*
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* The policy returned by this function has to be released with the help of
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* cpufreq_cpu_put() to balance its kobject reference counter properly.
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*/
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struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu)
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{
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struct cpufreq_policy *policy = NULL;
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unsigned long flags;
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if (WARN_ON(cpu >= nr_cpu_ids))
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return NULL;
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/* get the cpufreq driver */
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read_lock_irqsave(&cpufreq_driver_lock, flags);
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if (cpufreq_driver) {
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/* get the CPU */
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policy = cpufreq_cpu_get_raw(cpu);
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if (policy)
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kobject_get(&policy->kobj);
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}
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read_unlock_irqrestore(&cpufreq_driver_lock, flags);
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return policy;
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}
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EXPORT_SYMBOL_GPL(cpufreq_cpu_get);
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/**
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* cpufreq_cpu_put - Decrement kobject usage counter for cpufreq policy.
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* @policy: cpufreq policy returned by cpufreq_cpu_get().
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*/
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void cpufreq_cpu_put(struct cpufreq_policy *policy)
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{
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kobject_put(&policy->kobj);
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}
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EXPORT_SYMBOL_GPL(cpufreq_cpu_put);
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/**
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* cpufreq_cpu_release - Unlock a policy and decrement its usage counter.
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* @policy: cpufreq policy returned by cpufreq_cpu_acquire().
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*/
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void cpufreq_cpu_release(struct cpufreq_policy *policy)
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{
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if (WARN_ON(!policy))
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return;
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lockdep_assert_held(&policy->rwsem);
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up_write(&policy->rwsem);
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cpufreq_cpu_put(policy);
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}
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/**
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* cpufreq_cpu_acquire - Find policy for a CPU, mark it as busy and lock it.
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* @cpu: CPU to find the policy for.
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*
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* Call cpufreq_cpu_get() to get a reference on the cpufreq policy for @cpu and
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* if the policy returned by it is not NULL, acquire its rwsem for writing.
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* Return the policy if it is active or release it and return NULL otherwise.
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*
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* The policy returned by this function has to be released with the help of
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* cpufreq_cpu_release() in order to release its rwsem and balance its usage
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* counter properly.
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*/
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struct cpufreq_policy *cpufreq_cpu_acquire(unsigned int cpu)
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{
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struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
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if (!policy)
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return NULL;
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down_write(&policy->rwsem);
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if (policy_is_inactive(policy)) {
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cpufreq_cpu_release(policy);
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return NULL;
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}
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return policy;
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}
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/*********************************************************************
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* EXTERNALLY AFFECTING FREQUENCY CHANGES *
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*********************************************************************/
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/**
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* adjust_jiffies - Adjust the system "loops_per_jiffy".
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* @val: CPUFREQ_PRECHANGE or CPUFREQ_POSTCHANGE.
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* @ci: Frequency change information.
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*
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* This function alters the system "loops_per_jiffy" for the clock
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* speed change. Note that loops_per_jiffy cannot be updated on SMP
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* systems as each CPU might be scaled differently. So, use the arch
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* per-CPU loops_per_jiffy value wherever possible.
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*/
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static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci)
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{
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#ifndef CONFIG_SMP
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static unsigned long l_p_j_ref;
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static unsigned int l_p_j_ref_freq;
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if (ci->flags & CPUFREQ_CONST_LOOPS)
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return;
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if (!l_p_j_ref_freq) {
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l_p_j_ref = loops_per_jiffy;
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l_p_j_ref_freq = ci->old;
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pr_debug("saving %lu as reference value for loops_per_jiffy; freq is %u kHz\n",
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l_p_j_ref, l_p_j_ref_freq);
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}
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if (val == CPUFREQ_POSTCHANGE && ci->old != ci->new) {
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loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq,
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ci->new);
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pr_debug("scaling loops_per_jiffy to %lu for frequency %u kHz\n",
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loops_per_jiffy, ci->new);
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}
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#endif
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}
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/**
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* cpufreq_notify_transition - Notify frequency transition and adjust jiffies.
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* @policy: cpufreq policy to enable fast frequency switching for.
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* @freqs: contain details of the frequency update.
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* @state: set to CPUFREQ_PRECHANGE or CPUFREQ_POSTCHANGE.
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*
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* This function calls the transition notifiers and adjust_jiffies().
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*
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* It is called twice on all CPU frequency changes that have external effects.
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*/
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static void cpufreq_notify_transition(struct cpufreq_policy *policy,
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struct cpufreq_freqs *freqs,
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unsigned int state)
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{
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int cpu;
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BUG_ON(irqs_disabled());
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if (cpufreq_disabled())
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return;
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freqs->policy = policy;
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freqs->flags = cpufreq_driver->flags;
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pr_debug("notification %u of frequency transition to %u kHz\n",
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state, freqs->new);
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switch (state) {
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case CPUFREQ_PRECHANGE:
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/*
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* Detect if the driver reported a value as "old frequency"
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* which is not equal to what the cpufreq core thinks is
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* "old frequency".
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*/
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if (policy->cur && policy->cur != freqs->old) {
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pr_debug("Warning: CPU frequency is %u, cpufreq assumed %u kHz\n",
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freqs->old, policy->cur);
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freqs->old = policy->cur;
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}
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srcu_notifier_call_chain(&cpufreq_transition_notifier_list,
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CPUFREQ_PRECHANGE, freqs);
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adjust_jiffies(CPUFREQ_PRECHANGE, freqs);
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break;
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case CPUFREQ_POSTCHANGE:
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adjust_jiffies(CPUFREQ_POSTCHANGE, freqs);
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pr_debug("FREQ: %u - CPUs: %*pbl\n", freqs->new,
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cpumask_pr_args(policy->cpus));
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for_each_cpu(cpu, policy->cpus)
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trace_cpu_frequency(freqs->new, cpu);
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srcu_notifier_call_chain(&cpufreq_transition_notifier_list,
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CPUFREQ_POSTCHANGE, freqs);
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cpufreq_stats_record_transition(policy, freqs->new);
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policy->cur = freqs->new;
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}
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}
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/* Do post notifications when there are chances that transition has failed */
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static void cpufreq_notify_post_transition(struct cpufreq_policy *policy,
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struct cpufreq_freqs *freqs, int transition_failed)
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{
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cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE);
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if (!transition_failed)
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return;
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swap(freqs->old, freqs->new);
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cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE);
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cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE);
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}
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void cpufreq_freq_transition_begin(struct cpufreq_policy *policy,
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struct cpufreq_freqs *freqs)
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{
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/*
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* Catch double invocations of _begin() which lead to self-deadlock.
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* ASYNC_NOTIFICATION drivers are left out because the cpufreq core
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* doesn't invoke _begin() on their behalf, and hence the chances of
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* double invocations are very low. Moreover, there are scenarios
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* where these checks can emit false-positive warnings in these
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* drivers; so we avoid that by skipping them altogether.
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*/
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WARN_ON(!(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION)
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&& current == policy->transition_task);
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wait:
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wait_event(policy->transition_wait, !policy->transition_ongoing);
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spin_lock(&policy->transition_lock);
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if (unlikely(policy->transition_ongoing)) {
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spin_unlock(&policy->transition_lock);
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goto wait;
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}
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policy->transition_ongoing = true;
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policy->transition_task = current;
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spin_unlock(&policy->transition_lock);
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cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE);
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}
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EXPORT_SYMBOL_GPL(cpufreq_freq_transition_begin);
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void cpufreq_freq_transition_end(struct cpufreq_policy *policy,
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struct cpufreq_freqs *freqs, int transition_failed)
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{
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if (WARN_ON(!policy->transition_ongoing))
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return;
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cpufreq_notify_post_transition(policy, freqs, transition_failed);
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arch_set_freq_scale(policy->related_cpus,
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policy->cur,
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policy->cpuinfo.max_freq);
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policy->transition_ongoing = false;
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policy->transition_task = NULL;
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wake_up(&policy->transition_wait);
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}
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EXPORT_SYMBOL_GPL(cpufreq_freq_transition_end);
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/*
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* Fast frequency switching status count. Positive means "enabled", negative
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* means "disabled" and 0 means "not decided yet".
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*/
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static int cpufreq_fast_switch_count;
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static DEFINE_MUTEX(cpufreq_fast_switch_lock);
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static void cpufreq_list_transition_notifiers(void)
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{
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struct notifier_block *nb;
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pr_info("Registered transition notifiers:\n");
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mutex_lock(&cpufreq_transition_notifier_list.mutex);
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for (nb = cpufreq_transition_notifier_list.head; nb; nb = nb->next)
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pr_info("%pS\n", nb->notifier_call);
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mutex_unlock(&cpufreq_transition_notifier_list.mutex);
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}
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/**
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* cpufreq_enable_fast_switch - Enable fast frequency switching for policy.
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* @policy: cpufreq policy to enable fast frequency switching for.
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*
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* Try to enable fast frequency switching for @policy.
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*
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* 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);
|
|
|
|
static unsigned int __resolve_freq(struct cpufreq_policy *policy,
|
|
unsigned int target_freq, unsigned int relation)
|
|
{
|
|
unsigned int idx;
|
|
|
|
target_freq = clamp_val(target_freq, policy->min, policy->max);
|
|
|
|
if (!cpufreq_driver->target_index)
|
|
return target_freq;
|
|
|
|
idx = cpufreq_frequency_table_target(policy, target_freq, relation);
|
|
policy->cached_resolved_idx = idx;
|
|
policy->cached_target_freq = target_freq;
|
|
return policy->freq_table[idx].frequency;
|
|
}
|
|
|
|
/**
|
|
* cpufreq_driver_resolve_freq - Map a target frequency to a driver-supported
|
|
* one.
|
|
* @policy: associated policy to interrogate
|
|
* @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)
|
|
{
|
|
return __resolve_freq(policy, target_freq, CPUFREQ_RELATION_L);
|
|
}
|
|
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 kobj_attribute *attr, char *buf)
|
|
{
|
|
return sprintf(buf, "%d\n", cpufreq_driver->boost_enabled);
|
|
}
|
|
|
|
static ssize_t store_boost(struct kobject *kobj, struct kobj_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;
|
|
}
|
|
|
|
static struct cpufreq_governor *get_governor(const char *str_governor)
|
|
{
|
|
struct cpufreq_governor *t;
|
|
|
|
mutex_lock(&cpufreq_governor_mutex);
|
|
t = find_governor(str_governor);
|
|
if (!t)
|
|
goto unlock;
|
|
|
|
if (!try_module_get(t->owner))
|
|
t = NULL;
|
|
|
|
unlock:
|
|
mutex_unlock(&cpufreq_governor_mutex);
|
|
|
|
return t;
|
|
}
|
|
|
|
static unsigned int cpufreq_parse_policy(char *str_governor)
|
|
{
|
|
if (!strncasecmp(str_governor, "performance", CPUFREQ_NAME_LEN))
|
|
return CPUFREQ_POLICY_PERFORMANCE;
|
|
|
|
if (!strncasecmp(str_governor, "powersave", CPUFREQ_NAME_LEN))
|
|
return CPUFREQ_POLICY_POWERSAVE;
|
|
|
|
return CPUFREQ_POLICY_UNKNOWN;
|
|
}
|
|
|
|
/**
|
|
* cpufreq_parse_governor - parse a governor string only for has_target()
|
|
* @str_governor: Governor name.
|
|
*/
|
|
static struct cpufreq_governor *cpufreq_parse_governor(char *str_governor)
|
|
{
|
|
struct cpufreq_governor *t;
|
|
|
|
t = get_governor(str_governor);
|
|
if (t)
|
|
return t;
|
|
|
|
if (request_module("cpufreq_%s", str_governor))
|
|
return NULL;
|
|
|
|
return get_governor(str_governor);
|
|
}
|
|
|
|
/*
|
|
* 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->setpolicy && cpufreq_driver->get)
|
|
ret = sprintf(buf, "%u\n", cpufreq_driver->get(policy->cpu));
|
|
else
|
|
ret = sprintf(buf, "%u\n", policy->cur);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* 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) \
|
|
{ \
|
|
unsigned long val; \
|
|
int ret; \
|
|
\
|
|
ret = sscanf(buf, "%lu", &val); \
|
|
if (ret != 1) \
|
|
return -EINVAL; \
|
|
\
|
|
ret = freq_qos_update_request(policy->object##_freq_req, val);\
|
|
return ret >= 0 ? count : ret; \
|
|
}
|
|
|
|
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)
|
|
{
|
|
char str_governor[16];
|
|
int ret;
|
|
|
|
ret = sscanf(buf, "%15s", str_governor);
|
|
if (ret != 1)
|
|
return -EINVAL;
|
|
|
|
if (cpufreq_driver->setpolicy) {
|
|
unsigned int new_pol;
|
|
|
|
new_pol = cpufreq_parse_policy(str_governor);
|
|
if (!new_pol)
|
|
return -EINVAL;
|
|
|
|
ret = cpufreq_set_policy(policy, NULL, new_pol);
|
|
} else {
|
|
struct cpufreq_governor *new_gov;
|
|
|
|
new_gov = cpufreq_parse_governor(str_governor);
|
|
if (!new_gov)
|
|
return -EINVAL;
|
|
|
|
ret = cpufreq_set_policy(policy, new_gov,
|
|
CPUFREQ_POLICY_UNKNOWN);
|
|
|
|
module_put(new_gov->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;
|
|
}
|
|
|
|
mutex_lock(&cpufreq_governor_mutex);
|
|
for_each_governor(t) {
|
|
if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char))
|
|
- (CPUFREQ_NAME_LEN + 2)))
|
|
break;
|
|
i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name);
|
|
}
|
|
mutex_unlock(&cpufreq_governor_mutex);
|
|
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;
|
|
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;
|
|
|
|
if (!fattr->show)
|
|
return -EIO;
|
|
|
|
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;
|
|
|
|
if (!fattr->store)
|
|
return -EIO;
|
|
|
|
/*
|
|
* 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 (unlikely(!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;
|
|
}
|
|
|
|
static int cpufreq_init_policy(struct cpufreq_policy *policy)
|
|
{
|
|
struct cpufreq_governor *gov = NULL;
|
|
unsigned int pol = CPUFREQ_POLICY_UNKNOWN;
|
|
int ret;
|
|
|
|
if (has_target()) {
|
|
/* Update policy governor to the one used before hotplug. */
|
|
gov = get_governor(policy->last_governor);
|
|
if (gov) {
|
|
pr_debug("Restoring governor %s for cpu %d\n",
|
|
gov->name, policy->cpu);
|
|
} else {
|
|
gov = get_governor(default_governor);
|
|
}
|
|
|
|
if (!gov) {
|
|
gov = cpufreq_default_governor();
|
|
__module_get(gov->owner);
|
|
}
|
|
|
|
} else {
|
|
|
|
/* Use the default policy if there is no last_policy. */
|
|
if (policy->last_policy) {
|
|
pol = policy->last_policy;
|
|
} else {
|
|
pol = cpufreq_parse_policy(default_governor);
|
|
/*
|
|
* In case the default governor is neither "performance"
|
|
* nor "powersave", fall back to the initial policy
|
|
* value set by the driver.
|
|
*/
|
|
if (pol == CPUFREQ_POLICY_UNKNOWN)
|
|
pol = policy->policy;
|
|
}
|
|
if (pol != CPUFREQ_POLICY_PERFORMANCE &&
|
|
pol != CPUFREQ_POLICY_POWERSAVE)
|
|
return -ENODATA;
|
|
}
|
|
|
|
ret = cpufreq_set_policy(policy, gov, pol);
|
|
if (gov)
|
|
module_put(gov->owner);
|
|
|
|
return ret;
|
|
}
|
|
|
|
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;
|
|
}
|
|
|
|
void refresh_frequency_limits(struct cpufreq_policy *policy)
|
|
{
|
|
if (!policy_is_inactive(policy)) {
|
|
pr_debug("updating policy for CPU %u\n", policy->cpu);
|
|
|
|
cpufreq_set_policy(policy, policy->governor, policy->policy);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(refresh_frequency_limits);
|
|
|
|
static void handle_update(struct work_struct *work)
|
|
{
|
|
struct cpufreq_policy *policy =
|
|
container_of(work, struct cpufreq_policy, update);
|
|
|
|
pr_debug("handle_update for cpu %u called\n", policy->cpu);
|
|
down_write(&policy->rwsem);
|
|
refresh_frequency_limits(policy);
|
|
up_write(&policy->rwsem);
|
|
}
|
|
|
|
static int cpufreq_notifier_min(struct notifier_block *nb, unsigned long freq,
|
|
void *data)
|
|
{
|
|
struct cpufreq_policy *policy = container_of(nb, struct cpufreq_policy, nb_min);
|
|
|
|
schedule_work(&policy->update);
|
|
return 0;
|
|
}
|
|
|
|
static int cpufreq_notifier_max(struct notifier_block *nb, unsigned long freq,
|
|
void *data)
|
|
{
|
|
struct cpufreq_policy *policy = container_of(nb, struct cpufreq_policy, nb_max);
|
|
|
|
schedule_work(&policy->update);
|
|
return 0;
|
|
}
|
|
|
|
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 struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu)
|
|
{
|
|
struct cpufreq_policy *policy;
|
|
struct device *dev = get_cpu_device(cpu);
|
|
int ret;
|
|
|
|
if (!dev)
|
|
return NULL;
|
|
|
|
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) {
|
|
dev_err(dev, "%s: failed to init policy->kobj: %d\n", __func__, ret);
|
|
/*
|
|
* The entire policy object will be freed below, but the extra
|
|
* memory allocated for the kobject name needs to be freed by
|
|
* releasing the kobject.
|
|
*/
|
|
kobject_put(&policy->kobj);
|
|
goto err_free_real_cpus;
|
|
}
|
|
|
|
freq_constraints_init(&policy->constraints);
|
|
|
|
policy->nb_min.notifier_call = cpufreq_notifier_min;
|
|
policy->nb_max.notifier_call = cpufreq_notifier_max;
|
|
|
|
ret = freq_qos_add_notifier(&policy->constraints, FREQ_QOS_MIN,
|
|
&policy->nb_min);
|
|
if (ret) {
|
|
dev_err(dev, "Failed to register MIN QoS notifier: %d (%*pbl)\n",
|
|
ret, cpumask_pr_args(policy->cpus));
|
|
goto err_kobj_remove;
|
|
}
|
|
|
|
ret = freq_qos_add_notifier(&policy->constraints, FREQ_QOS_MAX,
|
|
&policy->nb_max);
|
|
if (ret) {
|
|
dev_err(dev, "Failed to register MAX QoS notifier: %d (%*pbl)\n",
|
|
ret, cpumask_pr_args(policy->cpus));
|
|
goto err_min_qos_notifier;
|
|
}
|
|
|
|
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_min_qos_notifier:
|
|
freq_qos_remove_notifier(&policy->constraints, FREQ_QOS_MIN,
|
|
&policy->nb_min);
|
|
err_kobj_remove:
|
|
cpufreq_policy_put_kobj(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_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);
|
|
|
|
freq_qos_remove_notifier(&policy->constraints, FREQ_QOS_MAX,
|
|
&policy->nb_max);
|
|
freq_qos_remove_notifier(&policy->constraints, FREQ_QOS_MIN,
|
|
&policy->nb_min);
|
|
|
|
/* Cancel any pending policy->update work before freeing the policy. */
|
|
cancel_work_sync(&policy->update);
|
|
|
|
if (policy->max_freq_req) {
|
|
/*
|
|
* CPUFREQ_CREATE_POLICY notification is sent only after
|
|
* successfully adding max_freq_req request.
|
|
*/
|
|
blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
|
|
CPUFREQ_REMOVE_POLICY, policy);
|
|
freq_qos_remove_request(policy->max_freq_req);
|
|
}
|
|
|
|
freq_qos_remove_request(policy->min_freq_req);
|
|
kfree(policy->min_freq_req);
|
|
|
|
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;
|
|
}
|
|
|
|
if (!new_policy && cpufreq_driver->online) {
|
|
ret = cpufreq_driver->online(policy);
|
|
if (ret) {
|
|
pr_debug("%s: %d: initialization failed\n", __func__,
|
|
__LINE__);
|
|
goto out_exit_policy;
|
|
}
|
|
|
|
/* Recover policy->cpus using related_cpus */
|
|
cpumask_copy(policy->cpus, policy->related_cpus);
|
|
} else {
|
|
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("%s: %d: initialization failed\n", __func__,
|
|
__LINE__);
|
|
goto out_free_policy;
|
|
}
|
|
|
|
/*
|
|
* The initialization has succeeded and the policy is online.
|
|
* If there is a problem with its frequency table, take it
|
|
* offline and drop it.
|
|
*/
|
|
ret = cpufreq_table_validate_and_sort(policy);
|
|
if (ret)
|
|
goto out_offline_policy;
|
|
|
|
/* related_cpus should at least include policy->cpus. */
|
|
cpumask_copy(policy->related_cpus, policy->cpus);
|
|
}
|
|
|
|
down_write(&policy->rwsem);
|
|
/*
|
|
* 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) {
|
|
for_each_cpu(j, policy->related_cpus) {
|
|
per_cpu(cpufreq_cpu_data, j) = policy;
|
|
add_cpu_dev_symlink(policy, j);
|
|
}
|
|
|
|
policy->min_freq_req = kzalloc(2 * sizeof(*policy->min_freq_req),
|
|
GFP_KERNEL);
|
|
if (!policy->min_freq_req) {
|
|
ret = -ENOMEM;
|
|
goto out_destroy_policy;
|
|
}
|
|
|
|
ret = freq_qos_add_request(&policy->constraints,
|
|
policy->min_freq_req, FREQ_QOS_MIN,
|
|
policy->min);
|
|
if (ret < 0) {
|
|
/*
|
|
* So we don't call freq_qos_remove_request() for an
|
|
* uninitialized request.
|
|
*/
|
|
kfree(policy->min_freq_req);
|
|
policy->min_freq_req = NULL;
|
|
goto out_destroy_policy;
|
|
}
|
|
|
|
/*
|
|
* This must be initialized right here to avoid calling
|
|
* freq_qos_remove_request() on uninitialized request in case
|
|
* of errors.
|
|
*/
|
|
policy->max_freq_req = policy->min_freq_req + 1;
|
|
|
|
ret = freq_qos_add_request(&policy->constraints,
|
|
policy->max_freq_req, FREQ_QOS_MAX,
|
|
policy->max);
|
|
if (ret < 0) {
|
|
policy->max_freq_req = NULL;
|
|
goto out_destroy_policy;
|
|
}
|
|
|
|
blocking_notifier_call_chain(&cpufreq_policy_notifier_list,
|
|
CPUFREQ_CREATE_POLICY, policy);
|
|
}
|
|
|
|
if (cpufreq_driver->get && has_target()) {
|
|
policy->cur = cpufreq_driver->get(policy->cpu);
|
|
if (!policy->cur) {
|
|
ret = -EIO;
|
|
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()) {
|
|
unsigned int old_freq = policy->cur;
|
|
|
|
/* Are we running at unknown frequency ? */
|
|
ret = cpufreq_frequency_table_get_index(policy, old_freq);
|
|
if (ret == -EINVAL) {
|
|
ret = __cpufreq_driver_target(policy, old_freq - 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_info("%s: CPU%d: Running at unlisted initial frequency: %u KHz, changing to: %u KHz\n",
|
|
__func__, policy->cpu, old_freq, 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);
|
|
|
|
/*
|
|
* Register with the energy model before
|
|
* sched_cpufreq_governor_change() is called, which will result
|
|
* in rebuilding of the sched domains, which should only be done
|
|
* once the energy model is properly initialized for the policy
|
|
* first.
|
|
*
|
|
* Also, this should be called before the policy is registered
|
|
* with cooling framework.
|
|
*/
|
|
if (cpufreq_driver->register_em)
|
|
cpufreq_driver->register_em(policy);
|
|
}
|
|
|
|
ret = cpufreq_init_policy(policy);
|
|
if (ret) {
|
|
pr_err("%s: Failed to initialize policy for cpu: %d (%d)\n",
|
|
__func__, cpu, ret);
|
|
goto out_destroy_policy;
|
|
}
|
|
|
|
up_write(&policy->rwsem);
|
|
|
|
kobject_uevent(&policy->kobj, KOBJ_ADD);
|
|
|
|
if (cpufreq_thermal_control_enabled(cpufreq_driver))
|
|
policy->cdev = of_cpufreq_cooling_register(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_offline_policy:
|
|
if (cpufreq_driver->offline)
|
|
cpufreq_driver->offline(policy);
|
|
|
|
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_thermal_control_enabled(cpufreq_driver)) {
|
|
cpufreq_cooling_unregister(policy->cdev);
|
|
policy->cdev = NULL;
|
|
}
|
|
|
|
if (has_target())
|
|
cpufreq_exit_governor(policy);
|
|
|
|
/*
|
|
* Perform the ->offline() during light-weight tear-down, as
|
|
* that allows fast recovery when the CPU comes back.
|
|
*/
|
|
if (cpufreq_driver->offline) {
|
|
cpufreq_driver->offline(policy);
|
|
} else 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)) {
|
|
/* We did light-weight exit earlier, do full tear down now */
|
|
if (cpufreq_driver->offline)
|
|
cpufreq_driver->exit(policy);
|
|
|
|
cpufreq_policy_free(policy);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* cpufreq_out_of_sync - Fix up actual and saved CPU frequency difference.
|
|
* @policy: Policy managing CPUs.
|
|
* @new_freq: New CPU frequency.
|
|
*
|
|
* Adjust to the current frequency first and clean up later by either calling
|
|
* cpufreq_update_policy(), or scheduling 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);
|
|
}
|
|
|
|
static unsigned int cpufreq_verify_current_freq(struct cpufreq_policy *policy, bool update)
|
|
{
|
|
unsigned int new_freq;
|
|
|
|
new_freq = cpufreq_driver->get(policy->cpu);
|
|
if (!new_freq)
|
|
return 0;
|
|
|
|
/*
|
|
* If fast frequency switching is used with the given policy, the check
|
|
* against policy->cur is pointless, so skip it in that case.
|
|
*/
|
|
if (policy->fast_switch_enabled || !has_target())
|
|
return new_freq;
|
|
|
|
if (policy->cur != new_freq) {
|
|
cpufreq_out_of_sync(policy, new_freq);
|
|
if (update)
|
|
schedule_work(&policy->update);
|
|
}
|
|
|
|
return new_freq;
|
|
}
|
|
|
|
/**
|
|
* 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);
|
|
|
|
/**
|
|
* cpufreq_get_hw_max_freq - get the max hardware frequency of the CPU
|
|
* @cpu: CPU number
|
|
*
|
|
* The default return value is the max_freq field of cpuinfo.
|
|
*/
|
|
__weak unsigned int cpufreq_get_hw_max_freq(unsigned int cpu)
|
|
{
|
|
struct cpufreq_policy *policy = cpufreq_cpu_get(cpu);
|
|
unsigned int ret_freq = 0;
|
|
|
|
if (policy) {
|
|
ret_freq = policy->cpuinfo.max_freq;
|
|
cpufreq_cpu_put(policy);
|
|
}
|
|
|
|
return ret_freq;
|
|
}
|
|
EXPORT_SYMBOL(cpufreq_get_hw_max_freq);
|
|
|
|
static unsigned int __cpufreq_get(struct cpufreq_policy *policy)
|
|
{
|
|
if (unlikely(policy_is_inactive(policy)))
|
|
return 0;
|
|
|
|
return cpufreq_verify_current_freq(policy, true);
|
|
}
|
|
|
|
/**
|
|
* 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 (cpufreq_driver->get)
|
|
ret_freq = __cpufreq_get(policy);
|
|
up_read(&policy->rwsem);
|
|
|
|
cpufreq_cpu_put(policy);
|
|
}
|
|
|
|
return ret_freq;
|
|
}
|
|
EXPORT_SYMBOL(cpufreq_get);
|
|
|
|
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: %s\n", __func__,
|
|
cpufreq_driver->name);
|
|
}
|
|
|
|
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_driver_test_flags - Test cpufreq driver's flags against given ones.
|
|
* @flags: Flags to test against the current cpufreq driver's flags.
|
|
*
|
|
* Assumes that the driver is there, so callers must ensure that this is the
|
|
* case.
|
|
*/
|
|
bool cpufreq_driver_test_flags(u16 flags)
|
|
{
|
|
return !!(cpufreq_driver->flags & flags);
|
|
}
|
|
|
|
/**
|
|
* cpufreq_get_current_driver - Return the current driver's name.
|
|
*
|
|
* Return the name string of the currently registered 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 registered cpufreq driver, or NULL
|
|
* if no cpufreq driver has been registered.
|
|
*/
|
|
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 notifier with cpufreq.
|
|
* @nb: notifier function to register.
|
|
* @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER.
|
|
*
|
|
* Add a notifier to one of two lists: either a list of notifiers that run on
|
|
* clock rate changes (once before and once after every transition), or a list
|
|
* of notifiers that ron on cpufreq policy changes.
|
|
*
|
|
* This function may sleep and it has the same return values 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 notifier from cpufreq.
|
|
* @nb: notifier block to be unregistered.
|
|
* @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER.
|
|
*
|
|
* Remove a notifier from one of the cpufreq notifier lists.
|
|
*
|
|
* This function may sleep and it has the same return values 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)
|
|
{
|
|
unsigned int freq;
|
|
int cpu;
|
|
|
|
target_freq = clamp_val(target_freq, policy->min, policy->max);
|
|
freq = cpufreq_driver->fast_switch(policy, target_freq);
|
|
|
|
if (!freq)
|
|
return 0;
|
|
|
|
policy->cur = freq;
|
|
arch_set_freq_scale(policy->related_cpus, freq,
|
|
policy->cpuinfo.max_freq);
|
|
cpufreq_stats_record_transition(policy, freq);
|
|
|
|
if (trace_cpu_frequency_enabled()) {
|
|
for_each_cpu(cpu, policy->cpus)
|
|
trace_cpu_frequency(freq, cpu);
|
|
}
|
|
|
|
return freq;
|
|
}
|
|
EXPORT_SYMBOL_GPL(cpufreq_driver_fast_switch);
|
|
|
|
/**
|
|
* cpufreq_driver_adjust_perf - Adjust CPU performance level in one go.
|
|
* @cpu: Target CPU.
|
|
* @min_perf: Minimum (required) performance level (units of @capacity).
|
|
* @target_perf: Target (desired) performance level (units of @capacity).
|
|
* @capacity: Capacity of the target CPU.
|
|
*
|
|
* Carry out a fast performance level switch of @cpu without sleeping.
|
|
*
|
|
* The driver's ->adjust_perf() 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 a suitable performance level equal to or above
|
|
* @min_perf and preferably equal to or below @target_perf.
|
|
*
|
|
* 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 CPU and that it will never be called in
|
|
* parallel with either ->target() or ->target_index() or ->fast_switch() for
|
|
* the same CPU.
|
|
*/
|
|
void cpufreq_driver_adjust_perf(unsigned int cpu,
|
|
unsigned long min_perf,
|
|
unsigned long target_perf,
|
|
unsigned long capacity)
|
|
{
|
|
cpufreq_driver->adjust_perf(cpu, min_perf, target_perf, capacity);
|
|
}
|
|
|
|
/**
|
|
* cpufreq_driver_has_adjust_perf - Check "direct fast switch" callback.
|
|
*
|
|
* Return 'true' if the ->adjust_perf callback is present for the
|
|
* current driver or 'false' otherwise.
|
|
*/
|
|
bool cpufreq_driver_has_adjust_perf(void)
|
|
{
|
|
return !!cpufreq_driver->adjust_perf;
|
|
}
|
|
|
|
/* 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 restore_freq, intermediate_freq = 0;
|
|
unsigned int newfreq = policy->freq_table[index].frequency;
|
|
int retval = -EINVAL;
|
|
bool notify;
|
|
|
|
if (newfreq == policy->cur)
|
|
return 0;
|
|
|
|
/* Save last value to restore later on errors */
|
|
restore_freq = policy->cur;
|
|
|
|
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 = 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;
|
|
|
|
if (cpufreq_disabled())
|
|
return -ENODEV;
|
|
|
|
target_freq = __resolve_freq(policy, target_freq, relation);
|
|
|
|
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 &&
|
|
!(cpufreq_driver->flags & CPUFREQ_NEED_UPDATE_LIMITS))
|
|
return 0;
|
|
|
|
if (cpufreq_driver->target)
|
|
return cpufreq_driver->target(policy, target_freq, relation);
|
|
|
|
if (!cpufreq_driver->target_index)
|
|
return -EINVAL;
|
|
|
|
return __target_index(policy, policy->cached_resolved_idx);
|
|
}
|
|
EXPORT_SYMBOL_GPL(__cpufreq_driver_target);
|
|
|
|
int cpufreq_driver_target(struct cpufreq_policy *policy,
|
|
unsigned int target_freq,
|
|
unsigned int relation)
|
|
{
|
|
int ret;
|
|
|
|
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->flags & CPUFREQ_GOV_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;
|
|
}
|
|
}
|
|
|
|
policy->strict_target = !!(policy->governor->flags & CPUFREQ_GOV_STRICT_TARGET);
|
|
|
|
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);
|
|
}
|
|
|
|
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_verify_current_freq(policy, false);
|
|
|
|
if (policy->governor->start) {
|
|
ret = policy->governor->start(policy);
|
|
if (ret)
|
|
return ret;
|
|
}
|
|
|
|
if (policy->governor->limits)
|
|
policy->governor->limits(policy);
|
|
|
|
return 0;
|
|
}
|
|
|
|
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
|
|
* @cpu: CPU to find the policy for
|
|
*
|
|
* 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);
|
|
|
|
/**
|
|
* cpufreq_set_policy - Modify cpufreq policy parameters.
|
|
* @policy: Policy object to modify.
|
|
* @new_gov: Policy governor pointer.
|
|
* @new_pol: Policy value (for drivers with built-in governors).
|
|
*
|
|
* Invoke the cpufreq driver's ->verify() callback to sanity-check the frequency
|
|
* limits to be set for the policy, update @policy with the verified limits
|
|
* values and either invoke the driver's ->setpolicy() callback (if present) or
|
|
* carry out a governor update for @policy. That is, run the current governor's
|
|
* ->limits() callback (if @new_gov points to the same object as the one in
|
|
* @policy) or replace the governor for @policy with @new_gov.
|
|
*
|
|
* The cpuinfo part of @policy is not updated by this function.
|
|
*/
|
|
static int cpufreq_set_policy(struct cpufreq_policy *policy,
|
|
struct cpufreq_governor *new_gov,
|
|
unsigned int new_pol)
|
|
{
|
|
struct cpufreq_policy_data new_data;
|
|
struct cpufreq_governor *old_gov;
|
|
int ret;
|
|
|
|
memcpy(&new_data.cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo));
|
|
new_data.freq_table = policy->freq_table;
|
|
new_data.cpu = policy->cpu;
|
|
/*
|
|
* PM QoS framework collects all the requests from users and provide us
|
|
* the final aggregated value here.
|
|
*/
|
|
new_data.min = freq_qos_read_value(&policy->constraints, FREQ_QOS_MIN);
|
|
new_data.max = freq_qos_read_value(&policy->constraints, FREQ_QOS_MAX);
|
|
|
|
pr_debug("setting new policy for CPU %u: %u - %u kHz\n",
|
|
new_data.cpu, new_data.min, new_data.max);
|
|
|
|
/*
|
|
* Verify that the CPU speed can be set within these limits and make sure
|
|
* that min <= max.
|
|
*/
|
|
ret = cpufreq_driver->verify(&new_data);
|
|
if (ret)
|
|
return ret;
|
|
|
|
policy->min = new_data.min;
|
|
policy->max = new_data.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_pol;
|
|
pr_debug("setting range\n");
|
|
return cpufreq_driver->setpolicy(policy);
|
|
}
|
|
|
|
if (new_gov == policy->governor) {
|
|
pr_debug("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_gov;
|
|
ret = cpufreq_init_governor(policy);
|
|
if (!ret) {
|
|
ret = cpufreq_start_governor(policy);
|
|
if (!ret) {
|
|
pr_debug("governor change\n");
|
|
sched_cpufreq_governor_change(policy, old_gov);
|
|
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 to re-evaluate the policy for.
|
|
*
|
|
* Update the current frequency for the cpufreq policy of @cpu and use
|
|
* cpufreq_set_policy() to re-apply the min and max limits, which triggers the
|
|
* evaluation of policy notifiers and the cpufreq driver's ->verify() callback
|
|
* for the policy in question, among other things.
|
|
*/
|
|
void cpufreq_update_policy(unsigned int cpu)
|
|
{
|
|
struct cpufreq_policy *policy = cpufreq_cpu_acquire(cpu);
|
|
|
|
if (!policy)
|
|
return;
|
|
|
|
/*
|
|
* BIOS might change freq behind our back
|
|
* -> ask driver for current freq and notify governors about a change
|
|
*/
|
|
if (cpufreq_driver->get && has_target() &&
|
|
(cpufreq_suspended || WARN_ON(!cpufreq_verify_current_freq(policy, false))))
|
|
goto unlock;
|
|
|
|
refresh_frequency_limits(policy);
|
|
|
|
unlock:
|
|
cpufreq_cpu_release(policy);
|
|
}
|
|
EXPORT_SYMBOL(cpufreq_update_policy);
|
|
|
|
/**
|
|
* cpufreq_update_limits - Update policy limits for a given CPU.
|
|
* @cpu: CPU to update the policy limits for.
|
|
*
|
|
* Invoke the driver's ->update_limits callback if present or call
|
|
* cpufreq_update_policy() for @cpu.
|
|
*/
|
|
void cpufreq_update_limits(unsigned int cpu)
|
|
{
|
|
if (cpufreq_driver->update_limits)
|
|
cpufreq_driver->update_limits(cpu);
|
|
else
|
|
cpufreq_update_policy(cpu);
|
|
}
|
|
EXPORT_SYMBOL_GPL(cpufreq_update_limits);
|
|
|
|
/*********************************************************************
|
|
* BOOST *
|
|
*********************************************************************/
|
|
static int cpufreq_boost_set_sw(struct cpufreq_policy *policy, int state)
|
|
{
|
|
int ret;
|
|
|
|
if (!policy->freq_table)
|
|
return -ENXIO;
|
|
|
|
ret = cpufreq_frequency_table_cpuinfo(policy, policy->freq_table);
|
|
if (ret) {
|
|
pr_err("%s: Policy frequency update failed\n", __func__);
|
|
return ret;
|
|
}
|
|
|
|
ret = freq_qos_update_request(policy->max_freq_req, policy->max);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
return 0;
|
|
}
|
|
|
|
int cpufreq_boost_trigger_state(int state)
|
|
{
|
|
struct cpufreq_policy *policy;
|
|
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);
|
|
|
|
cpus_read_lock();
|
|
for_each_active_policy(policy) {
|
|
ret = cpufreq_driver->set_boost(policy, state);
|
|
if (ret)
|
|
goto err_reset_state;
|
|
}
|
|
cpus_read_unlock();
|
|
|
|
return 0;
|
|
|
|
err_reset_state:
|
|
cpus_read_unlock();
|
|
|
|
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 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;
|
|
|
|
/*
|
|
* The cpufreq core depends heavily on the availability of device
|
|
* structure, make sure they are available before proceeding further.
|
|
*/
|
|
if (!get_cpu_device(0))
|
|
return -EPROBE_DEFER;
|
|
|
|
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) ||
|
|
(!driver_data->online != !driver_data->offline))
|
|
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);
|
|
|
|
/*
|
|
* Mark support for the scheduler's frequency invariance engine for
|
|
* drivers that implement target(), target_index() or fast_switch().
|
|
*/
|
|
if (!cpufreq_driver->setpolicy) {
|
|
static_branch_enable_cpuslocked(&cpufreq_freq_invariance);
|
|
pr_debug("supports frequency invariance");
|
|
}
|
|
|
|
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 (unlikely(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();
|
|
static_branch_disable_cpuslocked(&cpufreq_freq_invariance);
|
|
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);
|
|
|
|
static int __init cpufreq_core_init(void)
|
|
{
|
|
struct cpufreq_governor *gov = cpufreq_default_governor();
|
|
|
|
if (cpufreq_disabled())
|
|
return -ENODEV;
|
|
|
|
cpufreq_global_kobject = kobject_create_and_add("cpufreq", &cpu_subsys.dev_root->kobj);
|
|
BUG_ON(!cpufreq_global_kobject);
|
|
|
|
if (!strlen(default_governor))
|
|
strncpy(default_governor, gov->name, CPUFREQ_NAME_LEN);
|
|
|
|
return 0;
|
|
}
|
|
module_param(off, int, 0444);
|
|
module_param_string(default_governor, default_governor, CPUFREQ_NAME_LEN, 0444);
|
|
core_initcall(cpufreq_core_init);
|