| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Viresh Kumar | 2924 | 31.71% | 113 | 34.98% |
| Dave Jones | 1925 | 20.87% | 42 | 13.00% |
| Rafael J. Wysocki | 1336 | 14.49% | 43 | 13.31% |
| Lukasz Majewski | 395 | 4.28% | 2 | 0.62% |
| Dominik Brodowski | 386 | 4.19% | 10 | 3.10% |
| Srivatsa S. Bhat | 346 | 3.75% | 8 | 2.48% |
| Venkatesh Pallipadi | 274 | 2.97% | 3 | 0.93% |
| Patrick Mochel | 231 | 2.50% | 5 | 1.55% |
| Thomas Renninger | 205 | 2.22% | 10 | 3.10% |
| Dirk Brandewie | 117 | 1.27% | 4 | 1.24% |
| Jeremy Fitzhardinge | 88 | 0.95% | 2 | 0.62% |
| Steve Muckle | 72 | 0.78% | 2 | 0.62% |
| Konrad Rzeszutek Wilk | 68 | 0.74% | 1 | 0.31% |
| Darrick J. Wong | 61 | 0.66% | 1 | 0.31% |
| Jesse Barnes | 52 | 0.56% | 1 | 0.31% |
| Sebastian Andrzej Siewior | 52 | 0.56% | 5 | 1.55% |
| Len Brown | 51 | 0.55% | 2 | 0.62% |
| Chen Yu | 38 | 0.41% | 1 | 0.31% |
| Benjamin Herrenschmidt | 36 | 0.39% | 1 | 0.31% |
| Richard Cochran | 35 | 0.38% | 1 | 0.31% |
| Srinivas Pandruvada | 35 | 0.38% | 2 | 0.62% |
| Prarit Bhargava | 33 | 0.36% | 2 | 0.62% |
| Kay Sievers | 31 | 0.34% | 1 | 0.31% |
| Borislav Petkov | 30 | 0.33% | 2 | 0.62% |
| Nathan Zimmer | 28 | 0.30% | 2 | 0.62% |
| Thomas Petazzoni | 26 | 0.28% | 1 | 0.31% |
| Dietmar Eggemann | 23 | 0.25% | 1 | 0.31% |
| Doug Anderson | 22 | 0.24% | 1 | 0.31% |
| Jiri Slaby | 22 | 0.24% | 1 | 0.31% |
| Tomeu Vizoso | 19 | 0.21% | 1 | 0.31% |
| Gautham R. Shenoy | 17 | 0.18% | 1 | 0.31% |
| Alan Stern | 16 | 0.17% | 2 | 0.62% |
| Mike Travis | 16 | 0.17% | 1 | 0.31% |
| Andrew Morton | 15 | 0.16% | 2 | 0.62% |
| Jason Baron | 15 | 0.16% | 1 | 0.31% |
| Lan Tianyu | 12 | 0.13% | 2 | 0.62% |
| Ethan Zhao | 12 | 0.13% | 1 | 0.31% |
| CHIKAMA masaki | 10 | 0.11% | 1 | 0.31% |
| Waiman Long | 10 | 0.11% | 1 | 0.31% |
| Greg Kroah-Hartman | 10 | 0.11% | 1 | 0.31% |
| Mattia Dongili | 10 | 0.11% | 1 | 0.31% |
| Bo Yan | 9 | 0.10% | 1 | 0.31% |
| Aaron Plattner | 8 | 0.09% | 2 | 0.62% |
| Stratos Karafotis | 8 | 0.09% | 1 | 0.31% |
| Rusty Russell | 8 | 0.09% | 1 | 0.31% |
| Pankaj Gupta | 8 | 0.09% | 1 | 0.31% |
| Frédéric Weisbecker | 7 | 0.08% | 1 | 0.31% |
| Joe Perches | 5 | 0.05% | 1 | 0.31% |
| David Arcari | 5 | 0.05% | 1 | 0.31% |
| Andres Salomon | 5 | 0.05% | 1 | 0.31% |
| Ruchi Kandoi | 5 | 0.05% | 1 | 0.31% |
| Ahmed S. Darwish | 4 | 0.04% | 1 | 0.31% |
| Geert Uytterhoeven | 4 | 0.04% | 1 | 0.31% |
| Julia Lawall | 4 | 0.04% | 1 | 0.31% |
| Bartlomiej Zolnierkiewicz | 3 | 0.03% | 1 | 0.31% |
| Ashok Raj | 3 | 0.03% | 1 | 0.31% |
| Rasmus Villemoes | 3 | 0.03% | 1 | 0.31% |
| Stephen Boyd | 3 | 0.03% | 1 | 0.31% |
| Shailendra Verma | 2 | 0.02% | 1 | 0.31% |
| Kees Cook | 2 | 0.02% | 1 | 0.31% |
| Jacob Shin | 2 | 0.02% | 1 | 0.31% |
| Mathieu Desnoyers | 2 | 0.02% | 1 | 0.31% |
| Jonathan Corbet | 2 | 0.02% | 1 | 0.31% |
| Eric Biggers | 2 | 0.02% | 2 | 0.62% |
| Américo Wang | 2 | 0.02% | 1 | 0.31% |
| Emese Revfy | 1 | 0.01% | 1 | 0.31% |
| Tao Wang | 1 | 0.01% | 1 | 0.31% |
| Chris Wright | 1 | 0.01% | 1 | 0.31% |
| David Howells | 1 | 0.01% | 1 | 0.31% |
| Michael Hayes | 1 | 0.01% | 1 | 0.31% |
| Alexander Chiang | 1 | 0.01% | 1 | 0.31% |
| Lucas De Marchi | 1 | 0.01% | 1 | 0.31% |
| Pan Xinhui | 1 | 0.01% | 1 | 0.31% |
| Afzal Mohammed | 1 | 0.01% | 1 | 0.31% |
| Dhaval Giani | 1 | 0.01% | 1 | 0.31% |
| Rashika Kheria | 1 | 0.01% | 1 | 0.31% |
| Yinghai Lu | 1 | 0.01% | 1 | 0.31% |
| Total | 9222 | 323 |
/* * linux/drivers/cpufreq/cpufreq.c * * Copyright (C) 2001 Russell King * (C) 2002 - 2003 Dominik Brodowski <linux@brodo.de> * (C) 2013 Viresh Kumar <viresh.kumar@linaro.org> * * Oct 2005 - Ashok Raj <ashok.raj@intel.com> * Added handling for CPU hotplug * Feb 2006 - Jacob Shin <jacob.shin@amd.com> * Fix handling for CPU hotplug -- affected CPUs * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/cpu.h> #include <linux/cpufreq.h> #include <linux/delay.h> #include <linux/device.h> #include <linux/init.h> #include <linux/kernel_stat.h> #include <linux/module.h> #include <linux/mutex.h> #include <linux/slab.h> #include <linux/suspend.h> #include <linux/syscore_ops.h> #include <linux/tick.h> #include <trace/events/power.h> static LIST_HEAD(cpufreq_policy_list); static inline bool policy_is_inactive(struct cpufreq_policy *policy) { return cpumask_empty(policy->cpus); } /* Macros to iterate over CPU policies */ #define for_each_suitable_policy(__policy, __active) \ list_for_each_entry(__policy, &cpufreq_policy_list, policy_list) \ if ((__active) == !policy_is_inactive(__policy)) #define for_each_active_policy(__policy) \ for_each_suitable_policy(__policy, true) #define for_each_inactive_policy(__policy) \ for_each_suitable_policy(__policy, false) #define for_each_policy(__policy) \ list_for_each_entry(__policy, &cpufreq_policy_list, policy_list) /* Iterate over governors */ static LIST_HEAD(cpufreq_governor_list); #define for_each_governor(__governor) \ list_for_each_entry(__governor, &cpufreq_governor_list, governor_list) /** * The "cpufreq driver" - the arch- or hardware-dependent low * level driver of CPUFreq support, and its spinlock. This lock * also protects the cpufreq_cpu_data array. */ static struct cpufreq_driver *cpufreq_driver; static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data); static DEFINE_RWLOCK(cpufreq_driver_lock); /* Flag to suspend/resume CPUFreq governors */ static bool cpufreq_suspended; static inline bool has_target(void) { return cpufreq_driver->target_index || cpufreq_driver->target; } /* internal prototypes */ static unsigned int __cpufreq_get(struct cpufreq_policy *policy); static int cpufreq_init_governor(struct cpufreq_policy *policy); static void cpufreq_exit_governor(struct cpufreq_policy *policy); static int cpufreq_start_governor(struct cpufreq_policy *policy); static void cpufreq_stop_governor(struct cpufreq_policy *policy); static void cpufreq_governor_limits(struct cpufreq_policy *policy); /** * Two notifier lists: the "policy" list is involved in the * validation process for a new CPU frequency policy; the * "transition" list for kernel code that needs to handle * changes to devices when the CPU clock speed changes. * The mutex locks both lists. */ static BLOCKING_NOTIFIER_HEAD(cpufreq_policy_notifier_list); SRCU_NOTIFIER_HEAD_STATIC(cpufreq_transition_notifier_list); static int off __read_mostly; static int cpufreq_disabled(void) { return off; } void disable_cpufreq(void) { off = 1; } static DEFINE_MUTEX(cpufreq_governor_mutex); bool have_governor_per_policy(void) { return !!(cpufreq_driver->flags & CPUFREQ_HAVE_GOVERNOR_PER_POLICY); } EXPORT_SYMBOL_GPL(have_governor_per_policy); struct kobject *get_governor_parent_kobj(struct cpufreq_policy *policy) { if (have_governor_per_policy()) return &policy->kobj; else return cpufreq_global_kobject; } EXPORT_SYMBOL_GPL(get_governor_parent_kobj); static inline u64 get_cpu_idle_time_jiffy(unsigned int cpu, u64 *wall) { u64 idle_time; u64 cur_wall_time; u64 busy_time; cur_wall_time = jiffies64_to_nsecs(get_jiffies_64()); busy_time = kcpustat_cpu(cpu).cpustat[CPUTIME_USER]; busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SYSTEM]; busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_IRQ]; busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_SOFTIRQ]; busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_STEAL]; busy_time += kcpustat_cpu(cpu).cpustat[CPUTIME_NICE]; idle_time = cur_wall_time - busy_time; if (wall) *wall = div_u64(cur_wall_time, NSEC_PER_USEC); return div_u64(idle_time, NSEC_PER_USEC); } u64 get_cpu_idle_time(unsigned int cpu, u64 *wall, int io_busy) { u64 idle_time = get_cpu_idle_time_us(cpu, io_busy ? wall : NULL); if (idle_time == -1ULL) return get_cpu_idle_time_jiffy(cpu, wall); else if (!io_busy) idle_time += get_cpu_iowait_time_us(cpu, wall); return idle_time; } EXPORT_SYMBOL_GPL(get_cpu_idle_time); __weak void arch_set_freq_scale(struct cpumask *cpus, unsigned long cur_freq, unsigned long max_freq) { } EXPORT_SYMBOL_GPL(arch_set_freq_scale); /* * This is a generic cpufreq init() routine which can be used by cpufreq * drivers of SMP systems. It will do following: * - validate & show freq table passed * - set policies transition latency * - policy->cpus with all possible CPUs */ int cpufreq_generic_init(struct cpufreq_policy *policy, struct cpufreq_frequency_table *table, unsigned int transition_latency) { policy->freq_table = table; policy->cpuinfo.transition_latency = transition_latency; /* * The driver only supports the SMP configuration where all processors * share the clock and voltage and clock. */ cpumask_setall(policy->cpus); return 0; } EXPORT_SYMBOL_GPL(cpufreq_generic_init); struct cpufreq_policy *cpufreq_cpu_get_raw(unsigned int cpu) { struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); return policy && cpumask_test_cpu(cpu, policy->cpus) ? policy : NULL; } EXPORT_SYMBOL_GPL(cpufreq_cpu_get_raw); unsigned int cpufreq_generic_get(unsigned int cpu) { struct cpufreq_policy *policy = cpufreq_cpu_get_raw(cpu); if (!policy || IS_ERR(policy->clk)) { pr_err("%s: No %s associated to cpu: %d\n", __func__, policy ? "clk" : "policy", cpu); return 0; } return clk_get_rate(policy->clk) / 1000; } EXPORT_SYMBOL_GPL(cpufreq_generic_get); /** * cpufreq_cpu_get: returns policy for a cpu and marks it busy. * * @cpu: cpu to find policy for. * * This returns policy for 'cpu', returns NULL if it doesn't exist. * It also increments the kobject reference count to mark it busy and so would * require a corresponding call to cpufreq_cpu_put() to decrement it back. * If corresponding call cpufreq_cpu_put() isn't made, the policy wouldn't be * freed as that depends on the kobj count. * * Return: A valid policy on success, otherwise NULL on failure. */ struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) { struct cpufreq_policy *policy = NULL; unsigned long flags; if (WARN_ON(cpu >= nr_cpu_ids)) return NULL; /* get the cpufreq driver */ read_lock_irqsave(&cpufreq_driver_lock, flags); if (cpufreq_driver) { /* get the CPU */ policy = cpufreq_cpu_get_raw(cpu); if (policy) kobject_get(&policy->kobj); } read_unlock_irqrestore(&cpufreq_driver_lock, flags); return policy; } EXPORT_SYMBOL_GPL(cpufreq_cpu_get); /** * cpufreq_cpu_put: Decrements the usage count of a policy * * @policy: policy earlier returned by cpufreq_cpu_get(). * * This decrements the kobject reference count incremented earlier by calling * cpufreq_cpu_get(). */ void cpufreq_cpu_put(struct cpufreq_policy *policy) { kobject_put(&policy->kobj); } EXPORT_SYMBOL_GPL(cpufreq_cpu_put); /********************************************************************* * EXTERNALLY AFFECTING FREQUENCY CHANGES * *********************************************************************/ /** * adjust_jiffies - adjust the system "loops_per_jiffy" * * This function alters the system "loops_per_jiffy" for the clock * speed change. Note that loops_per_jiffy cannot be updated on SMP * systems as each CPU might be scaled differently. So, use the arch * per-CPU loops_per_jiffy value wherever possible. */ static void adjust_jiffies(unsigned long val, struct cpufreq_freqs *ci) { #ifndef CONFIG_SMP static unsigned long l_p_j_ref; static unsigned int l_p_j_ref_freq; if (ci->flags & CPUFREQ_CONST_LOOPS) return; if (!l_p_j_ref_freq) { l_p_j_ref = loops_per_jiffy; l_p_j_ref_freq = ci->old; pr_debug("saving %lu as reference value for loops_per_jiffy; freq is %u kHz\n", l_p_j_ref, l_p_j_ref_freq); } if (val == CPUFREQ_POSTCHANGE && ci->old != ci->new) { loops_per_jiffy = cpufreq_scale(l_p_j_ref, l_p_j_ref_freq, ci->new); pr_debug("scaling loops_per_jiffy to %lu for frequency %u kHz\n", loops_per_jiffy, ci->new); } #endif } /** * cpufreq_notify_transition - Notify frequency transition and adjust_jiffies. * @policy: cpufreq policy to enable fast frequency switching for. * @freqs: contain details of the frequency update. * @state: set to CPUFREQ_PRECHANGE or CPUFREQ_POSTCHANGE. * * This function calls the transition notifiers and the "adjust_jiffies" * function. It is called twice on all CPU frequency changes that have * external effects. */ static void cpufreq_notify_transition(struct cpufreq_policy *policy, struct cpufreq_freqs *freqs, unsigned int state) { BUG_ON(irqs_disabled()); if (cpufreq_disabled()) return; freqs->flags = cpufreq_driver->flags; pr_debug("notification %u of frequency transition to %u kHz\n", state, freqs->new); switch (state) { case CPUFREQ_PRECHANGE: /* * Detect if the driver reported a value as "old frequency" * which is not equal to what the cpufreq core thinks is * "old frequency". */ if (!(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { if (policy->cur && (policy->cur != freqs->old)) { pr_debug("Warning: CPU frequency is %u, cpufreq assumed %u kHz\n", freqs->old, policy->cur); freqs->old = policy->cur; } } for_each_cpu(freqs->cpu, policy->cpus) { srcu_notifier_call_chain(&cpufreq_transition_notifier_list, CPUFREQ_PRECHANGE, freqs); } adjust_jiffies(CPUFREQ_PRECHANGE, freqs); break; case CPUFREQ_POSTCHANGE: adjust_jiffies(CPUFREQ_POSTCHANGE, freqs); pr_debug("FREQ: %u - CPUs: %*pbl\n", freqs->new, cpumask_pr_args(policy->cpus)); for_each_cpu(freqs->cpu, policy->cpus) { trace_cpu_frequency(freqs->new, freqs->cpu); srcu_notifier_call_chain(&cpufreq_transition_notifier_list, CPUFREQ_POSTCHANGE, freqs); } cpufreq_stats_record_transition(policy, freqs->new); policy->cur = freqs->new; } } /* Do post notifications when there are chances that transition has failed */ static void cpufreq_notify_post_transition(struct cpufreq_policy *policy, struct cpufreq_freqs *freqs, int transition_failed) { cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); if (!transition_failed) return; swap(freqs->old, freqs->new); cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); } void cpufreq_freq_transition_begin(struct cpufreq_policy *policy, struct cpufreq_freqs *freqs) { /* * Catch double invocations of _begin() which lead to self-deadlock. * ASYNC_NOTIFICATION drivers are left out because the cpufreq core * doesn't invoke _begin() on their behalf, and hence the chances of * double invocations are very low. Moreover, there are scenarios * where these checks can emit false-positive warnings in these * drivers; so we avoid that by skipping them altogether. */ WARN_ON(!(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION) && current == policy->transition_task); wait: wait_event(policy->transition_wait, !policy->transition_ongoing); spin_lock(&policy->transition_lock); if (unlikely(policy->transition_ongoing)) { spin_unlock(&policy->transition_lock); goto wait; } policy->transition_ongoing = true; policy->transition_task = current; spin_unlock(&policy->transition_lock); cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); } EXPORT_SYMBOL_GPL(cpufreq_freq_transition_begin); void cpufreq_freq_transition_end(struct cpufreq_policy *policy, struct cpufreq_freqs *freqs, int transition_failed) { if (WARN_ON(!policy->transition_ongoing)) return; cpufreq_notify_post_transition(policy, freqs, transition_failed); policy->transition_ongoing = false; policy->transition_task = NULL; wake_up(&policy->transition_wait); } EXPORT_SYMBOL_GPL(cpufreq_freq_transition_end); /* * Fast frequency switching status count. Positive means "enabled", negative * means "disabled" and 0 means "not decided yet". */ static int cpufreq_fast_switch_count; static DEFINE_MUTEX(cpufreq_fast_switch_lock); static void cpufreq_list_transition_notifiers(void) { struct notifier_block *nb; pr_info("Registered transition notifiers:\n"); mutex_lock(&cpufreq_transition_notifier_list.mutex); for (nb = cpufreq_transition_notifier_list.head; nb; nb = nb->next) pr_info("%pF\n", nb->notifier_call); mutex_unlock(&cpufreq_transition_notifier_list.mutex); } /** * cpufreq_enable_fast_switch - Enable fast frequency switching for policy. * @policy: cpufreq policy to enable fast frequency switching for. * * Try to enable fast frequency switching for @policy. * * The attempt will fail if there is at least one transition notifier registered * at this point, as fast frequency switching is quite fundamentally at odds * with transition notifiers. Thus if successful, it will make registration of * transition notifiers fail going forward. */ void cpufreq_enable_fast_switch(struct cpufreq_policy *policy) { lockdep_assert_held(&policy->rwsem); if (!policy->fast_switch_possible) return; mutex_lock(&cpufreq_fast_switch_lock); if (cpufreq_fast_switch_count >= 0) { cpufreq_fast_switch_count++; policy->fast_switch_enabled = true; } else { pr_warn("CPU%u: Fast frequency switching not enabled\n", policy->cpu); cpufreq_list_transition_notifiers(); } mutex_unlock(&cpufreq_fast_switch_lock); } EXPORT_SYMBOL_GPL(cpufreq_enable_fast_switch); /** * cpufreq_disable_fast_switch - Disable fast frequency switching for policy. * @policy: cpufreq policy to disable fast frequency switching for. */ void cpufreq_disable_fast_switch(struct cpufreq_policy *policy) { mutex_lock(&cpufreq_fast_switch_lock); if (policy->fast_switch_enabled) { policy->fast_switch_enabled = false; if (!WARN_ON(cpufreq_fast_switch_count <= 0)) cpufreq_fast_switch_count--; } mutex_unlock(&cpufreq_fast_switch_lock); } EXPORT_SYMBOL_GPL(cpufreq_disable_fast_switch); /** * cpufreq_driver_resolve_freq - Map a target frequency to a driver-supported * one. * @target_freq: target frequency to resolve. * * The target to driver frequency mapping is cached in the policy. * * Return: Lowest driver-supported frequency greater than or equal to the * given target_freq, subject to policy (min/max) and driver limitations. */ unsigned int cpufreq_driver_resolve_freq(struct cpufreq_policy *policy, unsigned int target_freq) { target_freq = clamp_val(target_freq, policy->min, policy->max); policy->cached_target_freq = target_freq; if (cpufreq_driver->target_index) { int idx; idx = cpufreq_frequency_table_target(policy, target_freq, CPUFREQ_RELATION_L); policy->cached_resolved_idx = idx; return policy->freq_table[idx].frequency; } if (cpufreq_driver->resolve_freq) return cpufreq_driver->resolve_freq(policy, target_freq); return target_freq; } EXPORT_SYMBOL_GPL(cpufreq_driver_resolve_freq); unsigned int cpufreq_policy_transition_delay_us(struct cpufreq_policy *policy) { unsigned int latency; if (policy->transition_delay_us) return policy->transition_delay_us; latency = policy->cpuinfo.transition_latency / NSEC_PER_USEC; if (latency) { /* * For platforms that can change the frequency very fast (< 10 * us), the above formula gives a decent transition delay. But * for platforms where transition_latency is in milliseconds, it * ends up giving unrealistic values. * * Cap the default transition delay to 10 ms, which seems to be * a reasonable amount of time after which we should reevaluate * the frequency. */ return min(latency * LATENCY_MULTIPLIER, (unsigned int)10000); } return LATENCY_MULTIPLIER; } EXPORT_SYMBOL_GPL(cpufreq_policy_transition_delay_us); /********************************************************************* * SYSFS INTERFACE * *********************************************************************/ static ssize_t show_boost(struct kobject *kobj, struct attribute *attr, char *buf) { return sprintf(buf, "%d\n", cpufreq_driver->boost_enabled); } static ssize_t store_boost(struct kobject *kobj, struct attribute *attr, const char *buf, size_t count) { int ret, enable; ret = sscanf(buf, "%d", &enable); if (ret != 1 || enable < 0 || enable > 1) return -EINVAL; if (cpufreq_boost_trigger_state(enable)) { pr_err("%s: Cannot %s BOOST!\n", __func__, enable ? "enable" : "disable"); return -EINVAL; } pr_debug("%s: cpufreq BOOST %s\n", __func__, enable ? "enabled" : "disabled"); return count; } define_one_global_rw(boost); static struct cpufreq_governor *find_governor(const char *str_governor) { struct cpufreq_governor *t; for_each_governor(t) if (!strncasecmp(str_governor, t->name, CPUFREQ_NAME_LEN)) return t; return NULL; } /** * cpufreq_parse_governor - parse a governor string */ static int cpufreq_parse_governor(char *str_governor, struct cpufreq_policy *policy) { if (cpufreq_driver->setpolicy) { if (!strncasecmp(str_governor, "performance", CPUFREQ_NAME_LEN)) { policy->policy = CPUFREQ_POLICY_PERFORMANCE; return 0; } if (!strncasecmp(str_governor, "powersave", CPUFREQ_NAME_LEN)) { policy->policy = CPUFREQ_POLICY_POWERSAVE; return 0; } } else { struct cpufreq_governor *t; mutex_lock(&cpufreq_governor_mutex); t = find_governor(str_governor); if (!t) { int ret; mutex_unlock(&cpufreq_governor_mutex); ret = request_module("cpufreq_%s", str_governor); if (ret) return -EINVAL; mutex_lock(&cpufreq_governor_mutex); t = find_governor(str_governor); } if (t && !try_module_get(t->owner)) t = NULL; mutex_unlock(&cpufreq_governor_mutex); if (t) { policy->governor = t; return 0; } } return -EINVAL; } /** * cpufreq_per_cpu_attr_read() / show_##file_name() - * print out cpufreq information * * Write out information from cpufreq_driver->policy[cpu]; object must be * "unsigned int". */ #define show_one(file_name, object) \ static ssize_t show_##file_name \ (struct cpufreq_policy *policy, char *buf) \ { \ return sprintf(buf, "%u\n", policy->object); \ } show_one(cpuinfo_min_freq, cpuinfo.min_freq); show_one(cpuinfo_max_freq, cpuinfo.max_freq); show_one(cpuinfo_transition_latency, cpuinfo.transition_latency); show_one(scaling_min_freq, min); show_one(scaling_max_freq, max); __weak unsigned int arch_freq_get_on_cpu(int cpu) { return 0; } static ssize_t show_scaling_cur_freq(struct cpufreq_policy *policy, char *buf) { ssize_t ret; unsigned int freq; freq = arch_freq_get_on_cpu(policy->cpu); if (freq) ret = sprintf(buf, "%u\n", freq); else if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) ret = sprintf(buf, "%u\n", cpufreq_driver->get(policy->cpu)); else ret = sprintf(buf, "%u\n", policy->cur); return ret; } static int cpufreq_set_policy(struct cpufreq_policy *policy, struct cpufreq_policy *new_policy); /** * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access */ #define store_one(file_name, object) \ static ssize_t store_##file_name \ (struct cpufreq_policy *policy, const char *buf, size_t count) \ { \ int ret, temp; \ struct cpufreq_policy new_policy; \ \ memcpy(&new_policy, policy, sizeof(*policy)); \ new_policy.min = policy->user_policy.min; \ new_policy.max = policy->user_policy.max; \ \ ret = sscanf(buf, "%u", &new_policy.object); \ if (ret != 1) \ return -EINVAL; \ \ temp = new_policy.object; \ ret = cpufreq_set_policy(policy, &new_policy); \ if (!ret) \ policy->user_policy.object = temp; \ \ return ret ? ret : count; \ } store_one(scaling_min_freq, min); store_one(scaling_max_freq, max); /** * show_cpuinfo_cur_freq - current CPU frequency as detected by hardware */ static ssize_t show_cpuinfo_cur_freq(struct cpufreq_policy *policy, char *buf) { unsigned int cur_freq = __cpufreq_get(policy); if (cur_freq) return sprintf(buf, "%u\n", cur_freq); return sprintf(buf, "<unknown>\n"); } /** * show_scaling_governor - show the current policy for the specified CPU */ static ssize_t show_scaling_governor(struct cpufreq_policy *policy, char *buf) { if (policy->policy == CPUFREQ_POLICY_POWERSAVE) return sprintf(buf, "powersave\n"); else if (policy->policy == CPUFREQ_POLICY_PERFORMANCE) return sprintf(buf, "performance\n"); else if (policy->governor) return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", policy->governor->name); return -EINVAL; } /** * store_scaling_governor - store policy for the specified CPU */ static ssize_t store_scaling_governor(struct cpufreq_policy *policy, const char *buf, size_t count) { int ret; char str_governor[16]; struct cpufreq_policy new_policy; memcpy(&new_policy, policy, sizeof(*policy)); ret = sscanf(buf, "%15s", str_governor); if (ret != 1) return -EINVAL; if (cpufreq_parse_governor(str_governor, &new_policy)) return -EINVAL; ret = cpufreq_set_policy(policy, &new_policy); if (new_policy.governor) module_put(new_policy.governor->owner); return ret ? ret : count; } /** * show_scaling_driver - show the cpufreq driver currently loaded */ static ssize_t show_scaling_driver(struct cpufreq_policy *policy, char *buf) { return scnprintf(buf, CPUFREQ_NAME_PLEN, "%s\n", cpufreq_driver->name); } /** * show_scaling_available_governors - show the available CPUfreq governors */ static ssize_t show_scaling_available_governors(struct cpufreq_policy *policy, char *buf) { ssize_t i = 0; struct cpufreq_governor *t; if (!has_target()) { i += sprintf(buf, "performance powersave"); goto out; } for_each_governor(t) { if (i >= (ssize_t) ((PAGE_SIZE / sizeof(char)) - (CPUFREQ_NAME_LEN + 2))) goto out; i += scnprintf(&buf[i], CPUFREQ_NAME_PLEN, "%s ", t->name); } out: i += sprintf(&buf[i], "\n"); return i; } ssize_t cpufreq_show_cpus(const struct cpumask *mask, char *buf) { ssize_t i = 0; unsigned int cpu; for_each_cpu(cpu, mask) { if (i) i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), " "); i += scnprintf(&buf[i], (PAGE_SIZE - i - 2), "%u", cpu); if (i >= (PAGE_SIZE - 5)) break; } i += sprintf(&buf[i], "\n"); return i; } EXPORT_SYMBOL_GPL(cpufreq_show_cpus); /** * show_related_cpus - show the CPUs affected by each transition even if * hw coordination is in use */ static ssize_t show_related_cpus(struct cpufreq_policy *policy, char *buf) { return cpufreq_show_cpus(policy->related_cpus, buf); } /** * show_affected_cpus - show the CPUs affected by each transition */ static ssize_t show_affected_cpus(struct cpufreq_policy *policy, char *buf) { return cpufreq_show_cpus(policy->cpus, buf); } static ssize_t store_scaling_setspeed(struct cpufreq_policy *policy, const char *buf, size_t count) { unsigned int freq = 0; unsigned int ret; if (!policy->governor || !policy->governor->store_setspeed) return -EINVAL; ret = sscanf(buf, "%u", &freq); if (ret != 1) return -EINVAL; policy->governor->store_setspeed(policy, freq); return count; } static ssize_t show_scaling_setspeed(struct cpufreq_policy *policy, char *buf) { if (!policy->governor || !policy->governor->show_setspeed) return sprintf(buf, "<unsupported>\n"); return policy->governor->show_setspeed(policy, buf); } /** * show_bios_limit - show the current cpufreq HW/BIOS limitation */ static ssize_t show_bios_limit(struct cpufreq_policy *policy, char *buf) { unsigned int limit; int ret; if (cpufreq_driver->bios_limit) { ret = cpufreq_driver->bios_limit(policy->cpu, &limit); if (!ret) return sprintf(buf, "%u\n", limit); } return sprintf(buf, "%u\n", policy->cpuinfo.max_freq); } cpufreq_freq_attr_ro_perm(cpuinfo_cur_freq, 0400); cpufreq_freq_attr_ro(cpuinfo_min_freq); cpufreq_freq_attr_ro(cpuinfo_max_freq); cpufreq_freq_attr_ro(cpuinfo_transition_latency); cpufreq_freq_attr_ro(scaling_available_governors); cpufreq_freq_attr_ro(scaling_driver); cpufreq_freq_attr_ro(scaling_cur_freq); cpufreq_freq_attr_ro(bios_limit); cpufreq_freq_attr_ro(related_cpus); cpufreq_freq_attr_ro(affected_cpus); cpufreq_freq_attr_rw(scaling_min_freq); cpufreq_freq_attr_rw(scaling_max_freq); cpufreq_freq_attr_rw(scaling_governor); cpufreq_freq_attr_rw(scaling_setspeed); static struct attribute *default_attrs[] = { &cpuinfo_min_freq.attr, &cpuinfo_max_freq.attr, &cpuinfo_transition_latency.attr, &scaling_min_freq.attr, &scaling_max_freq.attr, &affected_cpus.attr, &related_cpus.attr, &scaling_governor.attr, &scaling_driver.attr, &scaling_available_governors.attr, &scaling_setspeed.attr, NULL }; #define to_policy(k) container_of(k, struct cpufreq_policy, kobj) #define to_attr(a) container_of(a, struct freq_attr, attr) static ssize_t show(struct kobject *kobj, struct attribute *attr, char *buf) { struct cpufreq_policy *policy = to_policy(kobj); struct freq_attr *fattr = to_attr(attr); ssize_t ret; down_read(&policy->rwsem); ret = fattr->show(policy, buf); up_read(&policy->rwsem); return ret; } static ssize_t store(struct kobject *kobj, struct attribute *attr, const char *buf, size_t count) { struct cpufreq_policy *policy = to_policy(kobj); struct freq_attr *fattr = to_attr(attr); ssize_t ret = -EINVAL; /* * cpus_read_trylock() is used here to work around a circular lock * dependency problem with respect to the cpufreq_register_driver(). */ if (!cpus_read_trylock()) return -EBUSY; if (cpu_online(policy->cpu)) { down_write(&policy->rwsem); ret = fattr->store(policy, buf, count); up_write(&policy->rwsem); } cpus_read_unlock(); return ret; } static void cpufreq_sysfs_release(struct kobject *kobj) { struct cpufreq_policy *policy = to_policy(kobj); pr_debug("last reference is dropped\n"); complete(&policy->kobj_unregister); } static const struct sysfs_ops sysfs_ops = { .show = show, .store = store, }; static struct kobj_type ktype_cpufreq = { .sysfs_ops = &sysfs_ops, .default_attrs = default_attrs, .release = cpufreq_sysfs_release, }; static void add_cpu_dev_symlink(struct cpufreq_policy *policy, unsigned int cpu) { struct device *dev = get_cpu_device(cpu); if (!dev) return; if (cpumask_test_and_set_cpu(cpu, policy->real_cpus)) return; dev_dbg(dev, "%s: Adding symlink\n", __func__); if (sysfs_create_link(&dev->kobj, &policy->kobj, "cpufreq")) dev_err(dev, "cpufreq symlink creation failed\n"); } static void remove_cpu_dev_symlink(struct cpufreq_policy *policy, struct device *dev) { dev_dbg(dev, "%s: Removing symlink\n", __func__); sysfs_remove_link(&dev->kobj, "cpufreq"); } static int cpufreq_add_dev_interface(struct cpufreq_policy *policy) { struct freq_attr **drv_attr; int ret = 0; /* set up files for this cpu device */ drv_attr = cpufreq_driver->attr; while (drv_attr && *drv_attr) { ret = sysfs_create_file(&policy->kobj, &((*drv_attr)->attr)); if (ret) return ret; drv_attr++; } if (cpufreq_driver->get) { ret = sysfs_create_file(&policy->kobj, &cpuinfo_cur_freq.attr); if (ret) return ret; } ret = sysfs_create_file(&policy->kobj, &scaling_cur_freq.attr); if (ret) return ret; if (cpufreq_driver->bios_limit) { ret = sysfs_create_file(&policy->kobj, &bios_limit.attr); if (ret) return ret; } return 0; } __weak struct cpufreq_governor *cpufreq_default_governor(void) { return NULL; } static int cpufreq_init_policy(struct cpufreq_policy *policy) { struct cpufreq_governor *gov = NULL; struct cpufreq_policy new_policy; memcpy(&new_policy, policy, sizeof(*policy)); /* Update governor of new_policy to the governor used before hotplug */ gov = find_governor(policy->last_governor); if (gov) { pr_debug("Restoring governor %s for cpu %d\n", policy->governor->name, policy->cpu); } else { gov = cpufreq_default_governor(); if (!gov) return -ENODATA; } new_policy.governor = gov; /* Use the default policy if there is no last_policy. */ if (cpufreq_driver->setpolicy) { if (policy->last_policy) new_policy.policy = policy->last_policy; else cpufreq_parse_governor(gov->name, &new_policy); } /* set default policy */ return cpufreq_set_policy(policy, &new_policy); } static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, unsigned int cpu) { int ret = 0; /* Has this CPU been taken care of already? */ if (cpumask_test_cpu(cpu, policy->cpus)) return 0; down_write(&policy->rwsem); if (has_target()) cpufreq_stop_governor(policy); cpumask_set_cpu(cpu, policy->cpus); if (has_target()) { ret = cpufreq_start_governor(policy); if (ret) pr_err("%s: Failed to start governor\n", __func__); } up_write(&policy->rwsem); return ret; } static void handle_update(struct work_struct *work) { struct cpufreq_policy *policy = container_of(work, struct cpufreq_policy, update); unsigned int cpu = policy->cpu; pr_debug("handle_update for cpu %u called\n", cpu); cpufreq_update_policy(cpu); } static struct cpufreq_policy *cpufreq_policy_alloc(unsigned int cpu) { struct cpufreq_policy *policy; int ret; policy = kzalloc(sizeof(*policy), GFP_KERNEL); if (!policy) return NULL; if (!alloc_cpumask_var(&policy->cpus, GFP_KERNEL)) goto err_free_policy; if (!zalloc_cpumask_var(&policy->related_cpus, GFP_KERNEL)) goto err_free_cpumask; if (!zalloc_cpumask_var(&policy->real_cpus, GFP_KERNEL)) goto err_free_rcpumask; ret = kobject_init_and_add(&policy->kobj, &ktype_cpufreq, cpufreq_global_kobject, "policy%u", cpu); if (ret) { pr_err("%s: failed to init policy->kobj: %d\n", __func__, ret); goto err_free_real_cpus; } INIT_LIST_HEAD(&policy->policy_list); init_rwsem(&policy->rwsem); spin_lock_init(&policy->transition_lock); init_waitqueue_head(&policy->transition_wait); init_completion(&policy->kobj_unregister); INIT_WORK(&policy->update, handle_update); policy->cpu = cpu; return policy; err_free_real_cpus: free_cpumask_var(policy->real_cpus); err_free_rcpumask: free_cpumask_var(policy->related_cpus); err_free_cpumask: free_cpumask_var(policy->cpus); err_free_policy: kfree(policy); return NULL; } static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy) { struct kobject *kobj; struct completion *cmp; down_write(&policy->rwsem); cpufreq_stats_free_table(policy); kobj = &policy->kobj; cmp = &policy->kobj_unregister; up_write(&policy->rwsem); kobject_put(kobj); /* * We need to make sure that the underlying kobj is * actually not referenced anymore by anybody before we * proceed with unloading. */ pr_debug("waiting for dropping of refcount\n"); wait_for_completion(cmp); pr_debug("wait complete\n"); } static void cpufreq_policy_free(struct cpufreq_policy *policy) { unsigned long flags; int cpu; /* Remove policy from list */ write_lock_irqsave(&cpufreq_driver_lock, flags); list_del(&policy->policy_list); for_each_cpu(cpu, policy->related_cpus) per_cpu(cpufreq_cpu_data, cpu) = NULL; write_unlock_irqrestore(&cpufreq_driver_lock, flags); cpufreq_policy_put_kobj(policy); free_cpumask_var(policy->real_cpus); free_cpumask_var(policy->related_cpus); free_cpumask_var(policy->cpus); kfree(policy); } static int cpufreq_online(unsigned int cpu) { struct cpufreq_policy *policy; bool new_policy; unsigned long flags; unsigned int j; int ret; pr_debug("%s: bringing CPU%u online\n", __func__, cpu); /* Check if this CPU already has a policy to manage it */ policy = per_cpu(cpufreq_cpu_data, cpu); if (policy) { WARN_ON(!cpumask_test_cpu(cpu, policy->related_cpus)); if (!policy_is_inactive(policy)) return cpufreq_add_policy_cpu(policy, cpu); /* This is the only online CPU for the policy. Start over. */ new_policy = false; down_write(&policy->rwsem); policy->cpu = cpu; policy->governor = NULL; up_write(&policy->rwsem); } else { new_policy = true; policy = cpufreq_policy_alloc(cpu); if (!policy) return -ENOMEM; } cpumask_copy(policy->cpus, cpumask_of(cpu)); /* call driver. From then on the cpufreq must be able * to accept all calls to ->verify and ->setpolicy for this CPU */ ret = cpufreq_driver->init(policy); if (ret) { pr_debug("initialization failed\n"); goto out_free_policy; } ret = cpufreq_table_validate_and_sort(policy); if (ret) goto out_exit_policy; down_write(&policy->rwsem); if (new_policy) { /* related_cpus should at least include policy->cpus. */ cpumask_copy(policy->related_cpus, policy->cpus); } /* * affected cpus must always be the one, which are online. We aren't * managing offline cpus here. */ cpumask_and(policy->cpus, policy->cpus, cpu_online_mask); if (new_policy) { policy->user_policy.min = policy->min; policy->user_policy.max = policy->max; for_each_cpu(j, policy->related_cpus) { per_cpu(cpufreq_cpu_data, j) = policy; add_cpu_dev_symlink(policy, j); } } else { policy->min = policy->user_policy.min; policy->max = policy->user_policy.max; } if (cpufreq_driver->get && !cpufreq_driver->setpolicy) { policy->cur = cpufreq_driver->get(policy->cpu); if (!policy->cur) { pr_err("%s: ->get() failed\n", __func__); goto out_destroy_policy; } } /* * Sometimes boot loaders set CPU frequency to a value outside of * frequency table present with cpufreq core. In such cases CPU might be * unstable if it has to run on that frequency for long duration of time * and so its better to set it to a frequency which is specified in * freq-table. This also makes cpufreq stats inconsistent as * cpufreq-stats would fail to register because current frequency of CPU * isn't found in freq-table. * * Because we don't want this change to effect boot process badly, we go * for the next freq which is >= policy->cur ('cur' must be set by now, * otherwise we will end up setting freq to lowest of the table as 'cur' * is initialized to zero). * * We are passing target-freq as "policy->cur - 1" otherwise * __cpufreq_driver_target() would simply fail, as policy->cur will be * equal to target-freq. */ if ((cpufreq_driver->flags & CPUFREQ_NEED_INITIAL_FREQ_CHECK) && has_target()) { /* Are we running at unknown frequency ? */ ret = cpufreq_frequency_table_get_index(policy, policy->cur); if (ret == -EINVAL) { /* Warn user and fix it */ pr_warn("%s: CPU%d: Running at unlisted freq: %u KHz\n", __func__, policy->cpu, policy->cur); ret = __cpufreq_driver_target(policy, policy->cur - 1, CPUFREQ_RELATION_L); /* * Reaching here after boot in a few seconds may not * mean that system will remain stable at "unknown" * frequency for longer duration. Hence, a BUG_ON(). */ BUG_ON(ret); pr_warn("%s: CPU%d: Unlisted initial frequency changed to: %u KHz\n", __func__, policy->cpu, policy->cur); } } if (new_policy) { ret = cpufreq_add_dev_interface(policy); if (ret) goto out_destroy_policy; cpufreq_stats_create_table(policy); write_lock_irqsave(&cpufreq_driver_lock, flags); list_add(&policy->policy_list, &cpufreq_policy_list); write_unlock_irqrestore(&cpufreq_driver_lock, flags); } ret = cpufreq_init_policy(policy); if (ret) { pr_err("%s: Failed to initialize policy for cpu: %d (%d)\n", __func__, cpu, ret); /* cpufreq_policy_free() will notify based on this */ new_policy = false; goto out_destroy_policy; } up_write(&policy->rwsem); kobject_uevent(&policy->kobj, KOBJ_ADD); /* Callback for handling stuff after policy is ready */ if (cpufreq_driver->ready) cpufreq_driver->ready(policy); pr_debug("initialization complete\n"); return 0; out_destroy_policy: for_each_cpu(j, policy->real_cpus) remove_cpu_dev_symlink(policy, get_cpu_device(j)); up_write(&policy->rwsem); out_exit_policy: if (cpufreq_driver->exit) cpufreq_driver->exit(policy); out_free_policy: cpufreq_policy_free(policy); return ret; } /** * cpufreq_add_dev - the cpufreq interface for a CPU device. * @dev: CPU device. * @sif: Subsystem interface structure pointer (not used) */ static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) { struct cpufreq_policy *policy; unsigned cpu = dev->id; int ret; dev_dbg(dev, "%s: adding CPU%u\n", __func__, cpu); if (cpu_online(cpu)) { ret = cpufreq_online(cpu); if (ret) return ret; } /* Create sysfs link on CPU registration */ policy = per_cpu(cpufreq_cpu_data, cpu); if (policy) add_cpu_dev_symlink(policy, cpu); return 0; } static int cpufreq_offline(unsigned int cpu) { struct cpufreq_policy *policy; int ret; pr_debug("%s: unregistering CPU %u\n", __func__, cpu); policy = cpufreq_cpu_get_raw(cpu); if (!policy) { pr_debug("%s: No cpu_data found\n", __func__); return 0; } down_write(&policy->rwsem); if (has_target()) cpufreq_stop_governor(policy); cpumask_clear_cpu(cpu, policy->cpus); if (policy_is_inactive(policy)) { if (has_target()) strncpy(policy->last_governor, policy->governor->name, CPUFREQ_NAME_LEN); else policy->last_policy = policy->policy; } else if (cpu == policy->cpu) { /* Nominate new CPU */ policy->cpu = cpumask_any(policy->cpus); } /* Start governor again for active policy */ if (!policy_is_inactive(policy)) { if (has_target()) { ret = cpufreq_start_governor(policy); if (ret) pr_err("%s: Failed to start governor\n", __func__); } goto unlock; } if (cpufreq_driver->stop_cpu) cpufreq_driver->stop_cpu(policy); if (has_target()) cpufreq_exit_governor(policy); /* * Perform the ->exit() even during light-weight tear-down, * since this is a core component, and is essential for the * subsequent light-weight ->init() to succeed. */ if (cpufreq_driver->exit) { cpufreq_driver->exit(policy); policy->freq_table = NULL; } unlock: up_write(&policy->rwsem); return 0; } /** * cpufreq_remove_dev - remove a CPU device * * Removes the cpufreq interface for a CPU device. */ static void cpufreq_remove_dev(struct device *dev, struct subsys_interface *sif) { unsigned int cpu = dev->id; struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); if (!policy) return; if (cpu_online(cpu)) cpufreq_offline(cpu); cpumask_clear_cpu(cpu, policy->real_cpus); remove_cpu_dev_symlink(policy, dev); if (cpumask_empty(policy->real_cpus)) cpufreq_policy_free(policy); } /** * cpufreq_out_of_sync - If actual and saved CPU frequency differs, we're * in deep trouble. * @policy: policy managing CPUs * @new_freq: CPU frequency the CPU actually runs at * * We adjust to current frequency first, and need to clean up later. * So either call to cpufreq_update_policy() or schedule handle_update()). */ static void cpufreq_out_of_sync(struct cpufreq_policy *policy, unsigned int new_freq) { struct cpufreq_freqs freqs; pr_debug("Warning: CPU frequency out of sync: cpufreq and timing core thinks of %u, is %u kHz\n", policy->cur, new_freq); freqs.old = policy->cur; freqs.new = new_freq; cpufreq_freq_transition_begin(policy, &freqs); cpufreq_freq_transition_end(policy, &freqs, 0); } /** * cpufreq_quick_get - get the CPU frequency (in kHz) from policy->cur * @cpu: CPU number * * This is the last known freq, without actually getting it from the driver. * Return value will be same as what is shown in scaling_cur_freq in sysfs. */ unsigned int cpufreq_quick_get(unsigned int cpu) { struct cpufreq_policy *policy; unsigned int ret_freq = 0; unsigned long flags; read_lock_irqsave(&cpufreq_driver_lock, flags); if (cpufreq_driver && cpufreq_driver->setpolicy && cpufreq_driver->get) { ret_freq = cpufreq_driver->get(cpu); read_unlock_irqrestore(&cpufreq_driver_lock, flags); return ret_freq; } read_unlock_irqrestore(&cpufreq_driver_lock, flags); policy = cpufreq_cpu_get(cpu); if (policy) { ret_freq = policy->cur; cpufreq_cpu_put(policy); } return ret_freq; } EXPORT_SYMBOL(cpufreq_quick_get); /** * cpufreq_quick_get_max - get the max reported CPU frequency for this CPU * @cpu: CPU number * * Just return the max possible frequency for a given CPU. */ unsigned int cpufreq_quick_get_max(unsigned int cpu) { struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); unsigned int ret_freq = 0; if (policy) { ret_freq = policy->max; cpufreq_cpu_put(policy); } return ret_freq; } EXPORT_SYMBOL(cpufreq_quick_get_max); static unsigned int __cpufreq_get(struct cpufreq_policy *policy) { unsigned int ret_freq = 0; if (!cpufreq_driver->get) return ret_freq; ret_freq = cpufreq_driver->get(policy->cpu); /* * Updating inactive policies is invalid, so avoid doing that. Also * if fast frequency switching is used with the given policy, the check * against policy->cur is pointless, so skip it in that case too. */ if (unlikely(policy_is_inactive(policy)) || policy->fast_switch_enabled) return ret_freq; if (ret_freq && policy->cur && !(cpufreq_driver->flags & CPUFREQ_CONST_LOOPS)) { /* verify no discrepancy between actual and saved value exists */ if (unlikely(ret_freq != policy->cur)) { cpufreq_out_of_sync(policy, ret_freq); schedule_work(&policy->update); } } return ret_freq; } /** * cpufreq_get - get the current CPU frequency (in kHz) * @cpu: CPU number * * Get the CPU current (static) CPU frequency */ unsigned int cpufreq_get(unsigned int cpu) { struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); unsigned int ret_freq = 0; if (policy) { down_read(&policy->rwsem); if (!policy_is_inactive(policy)) ret_freq = __cpufreq_get(policy); up_read(&policy->rwsem); cpufreq_cpu_put(policy); } return ret_freq; } EXPORT_SYMBOL(cpufreq_get); static unsigned int cpufreq_update_current_freq(struct cpufreq_policy *policy) { unsigned int new_freq; new_freq = cpufreq_driver->get(policy->cpu); if (!new_freq) return 0; if (!policy->cur) { pr_debug("cpufreq: Driver did not initialize current freq\n"); policy->cur = new_freq; } else if (policy->cur != new_freq && has_target()) { cpufreq_out_of_sync(policy, new_freq); } return new_freq; } static struct subsys_interface cpufreq_interface = { .name = "cpufreq", .subsys = &cpu_subsys, .add_dev = cpufreq_add_dev, .remove_dev = cpufreq_remove_dev, }; /* * In case platform wants some specific frequency to be configured * during suspend.. */ int cpufreq_generic_suspend(struct cpufreq_policy *policy) { int ret; if (!policy->suspend_freq) { pr_debug("%s: suspend_freq not defined\n", __func__); return 0; } pr_debug("%s: Setting suspend-freq: %u\n", __func__, policy->suspend_freq); ret = __cpufreq_driver_target(policy, policy->suspend_freq, CPUFREQ_RELATION_H); if (ret) pr_err("%s: unable to set suspend-freq: %u. err: %d\n", __func__, policy->suspend_freq, ret); return ret; } EXPORT_SYMBOL(cpufreq_generic_suspend); /** * cpufreq_suspend() - Suspend CPUFreq governors * * Called during system wide Suspend/Hibernate cycles for suspending governors * as some platforms can't change frequency after this point in suspend cycle. * Because some of the devices (like: i2c, regulators, etc) they use for * changing frequency are suspended quickly after this point. */ void cpufreq_suspend(void) { struct cpufreq_policy *policy; if (!cpufreq_driver) return; if (!has_target() && !cpufreq_driver->suspend) goto suspend; pr_debug("%s: Suspending Governors\n", __func__); for_each_active_policy(policy) { if (has_target()) { down_write(&policy->rwsem); cpufreq_stop_governor(policy); up_write(&policy->rwsem); } if (cpufreq_driver->suspend && cpufreq_driver->suspend(policy)) pr_err("%s: Failed to suspend driver: %p\n", __func__, policy); } suspend: cpufreq_suspended = true; } /** * cpufreq_resume() - Resume CPUFreq governors * * Called during system wide Suspend/Hibernate cycle for resuming governors that * are suspended with cpufreq_suspend(). */ void cpufreq_resume(void) { struct cpufreq_policy *policy; int ret; if (!cpufreq_driver) return; if (unlikely(!cpufreq_suspended)) return; cpufreq_suspended = false; if (!has_target() && !cpufreq_driver->resume) return; pr_debug("%s: Resuming Governors\n", __func__); for_each_active_policy(policy) { if (cpufreq_driver->resume && cpufreq_driver->resume(policy)) { pr_err("%s: Failed to resume driver: %p\n", __func__, policy); } else if (has_target()) { down_write(&policy->rwsem); ret = cpufreq_start_governor(policy); up_write(&policy->rwsem); if (ret) pr_err("%s: Failed to start governor for policy: %p\n", __func__, policy); } } } /** * cpufreq_get_current_driver - return current driver's name * * Return the name string of the currently loaded cpufreq driver * or NULL, if none. */ const char *cpufreq_get_current_driver(void) { if (cpufreq_driver) return cpufreq_driver->name; return NULL; } EXPORT_SYMBOL_GPL(cpufreq_get_current_driver); /** * cpufreq_get_driver_data - return current driver data * * Return the private data of the currently loaded cpufreq * driver, or NULL if no cpufreq driver is loaded. */ void *cpufreq_get_driver_data(void) { if (cpufreq_driver) return cpufreq_driver->driver_data; return NULL; } EXPORT_SYMBOL_GPL(cpufreq_get_driver_data); /********************************************************************* * NOTIFIER LISTS INTERFACE * *********************************************************************/ /** * cpufreq_register_notifier - register a driver with cpufreq * @nb: notifier function to register * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER * * Add a driver to one of two lists: either a list of drivers that * are notified about clock rate changes (once before and once after * the transition), or a list of drivers that are notified about * changes in cpufreq policy. * * This function may sleep, and has the same return conditions as * blocking_notifier_chain_register. */ int cpufreq_register_notifier(struct notifier_block *nb, unsigned int list) { int ret; if (cpufreq_disabled()) return -EINVAL; switch (list) { case CPUFREQ_TRANSITION_NOTIFIER: mutex_lock(&cpufreq_fast_switch_lock); if (cpufreq_fast_switch_count > 0) { mutex_unlock(&cpufreq_fast_switch_lock); return -EBUSY; } ret = srcu_notifier_chain_register( &cpufreq_transition_notifier_list, nb); if (!ret) cpufreq_fast_switch_count--; mutex_unlock(&cpufreq_fast_switch_lock); break; case CPUFREQ_POLICY_NOTIFIER: ret = blocking_notifier_chain_register( &cpufreq_policy_notifier_list, nb); break; default: ret = -EINVAL; } return ret; } EXPORT_SYMBOL(cpufreq_register_notifier); /** * cpufreq_unregister_notifier - unregister a driver with cpufreq * @nb: notifier block to be unregistered * @list: CPUFREQ_TRANSITION_NOTIFIER or CPUFREQ_POLICY_NOTIFIER * * Remove a driver from the CPU frequency notifier list. * * This function may sleep, and has the same return conditions as * blocking_notifier_chain_unregister. */ int cpufreq_unregister_notifier(struct notifier_block *nb, unsigned int list) { int ret; if (cpufreq_disabled()) return -EINVAL; switch (list) { case CPUFREQ_TRANSITION_NOTIFIER: mutex_lock(&cpufreq_fast_switch_lock); ret = srcu_notifier_chain_unregister( &cpufreq_transition_notifier_list, nb); if (!ret && !WARN_ON(cpufreq_fast_switch_count >= 0)) cpufreq_fast_switch_count++; mutex_unlock(&cpufreq_fast_switch_lock); break; case CPUFREQ_POLICY_NOTIFIER: ret = blocking_notifier_chain_unregister( &cpufreq_policy_notifier_list, nb); break; default: ret = -EINVAL; } return ret; } EXPORT_SYMBOL(cpufreq_unregister_notifier); /********************************************************************* * GOVERNORS * *********************************************************************/ /** * cpufreq_driver_fast_switch - Carry out a fast CPU frequency switch. * @policy: cpufreq policy to switch the frequency for. * @target_freq: New frequency to set (may be approximate). * * Carry out a fast frequency switch without sleeping. * * The driver's ->fast_switch() callback invoked by this function must be * suitable for being called from within RCU-sched read-side critical sections * and it is expected to select the minimum available frequency greater than or * equal to @target_freq (CPUFREQ_RELATION_L). * * This function must not be called if policy->fast_switch_enabled is unset. * * Governors calling this function must guarantee that it will never be invoked * twice in parallel for the same policy and that it will never be called in * parallel with either ->target() or ->target_index() for the same policy. * * Returns the actual frequency set for the CPU. * * If 0 is returned by the driver's ->fast_switch() callback to indicate an * error condition, the hardware configuration must be preserved. */ unsigned int cpufreq_driver_fast_switch(struct cpufreq_policy *policy, unsigned int target_freq) { target_freq = clamp_val(target_freq, policy->min, policy->max); return cpufreq_driver->fast_switch(policy, target_freq); } EXPORT_SYMBOL_GPL(cpufreq_driver_fast_switch); /* Must set freqs->new to intermediate frequency */ static int __target_intermediate(struct cpufreq_policy *policy, struct cpufreq_freqs *freqs, int index) { int ret; freqs->new = cpufreq_driver->get_intermediate(policy, index); /* We don't need to switch to intermediate freq */ if (!freqs->new) return 0; pr_debug("%s: cpu: %d, switching to intermediate freq: oldfreq: %u, intermediate freq: %u\n", __func__, policy->cpu, freqs->old, freqs->new); cpufreq_freq_transition_begin(policy, freqs); ret = cpufreq_driver->target_intermediate(policy, index); cpufreq_freq_transition_end(policy, freqs, ret); if (ret) pr_err("%s: Failed to change to intermediate frequency: %d\n", __func__, ret); return ret; } static int __target_index(struct cpufreq_policy *policy, int index) { struct cpufreq_freqs freqs = {.old = policy->cur, .flags = 0}; unsigned int intermediate_freq = 0; unsigned int newfreq = policy->freq_table[index].frequency; int retval = -EINVAL; bool notify; if (newfreq == policy->cur) return 0; notify = !(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION); if (notify) { /* Handle switching to intermediate frequency */ if (cpufreq_driver->get_intermediate) { retval = __target_intermediate(policy, &freqs, index); if (retval) return retval; intermediate_freq = freqs.new; /* Set old freq to intermediate */ if (intermediate_freq) freqs.old = freqs.new; } freqs.new = newfreq; pr_debug("%s: cpu: %d, oldfreq: %u, new freq: %u\n", __func__, policy->cpu, freqs.old, freqs.new); cpufreq_freq_transition_begin(policy, &freqs); } retval = cpufreq_driver->target_index(policy, index); if (retval) pr_err("%s: Failed to change cpu frequency: %d\n", __func__, retval); if (notify) { cpufreq_freq_transition_end(policy, &freqs, retval); /* * Failed after setting to intermediate freq? Driver should have * reverted back to initial frequency and so should we. Check * here for intermediate_freq instead of get_intermediate, in * case we haven't switched to intermediate freq at all. */ if (unlikely(retval && intermediate_freq)) { freqs.old = intermediate_freq; freqs.new = policy->restore_freq; cpufreq_freq_transition_begin(policy, &freqs); cpufreq_freq_transition_end(policy, &freqs, 0); } } return retval; } int __cpufreq_driver_target(struct cpufreq_policy *policy, unsigned int target_freq, unsigned int relation) { unsigned int old_target_freq = target_freq; int index; if (cpufreq_disabled()) return -ENODEV; /* Make sure that target_freq is within supported range */ target_freq = clamp_val(target_freq, policy->min, policy->max); pr_debug("target for CPU %u: %u kHz, relation %u, requested %u kHz\n", policy->cpu, target_freq, relation, old_target_freq); /* * This might look like a redundant call as we are checking it again * after finding index. But it is left intentionally for cases where * exactly same freq is called again and so we can save on few function * calls. */ if (target_freq == policy->cur) return 0; /* Save last value to restore later on errors */ policy->restore_freq = policy->cur; if (cpufreq_driver->target) return cpufreq_driver->target(policy, target_freq, relation); if (!cpufreq_driver->target_index) return -EINVAL; index = cpufreq_frequency_table_target(policy, target_freq, relation); return __target_index(policy, index); } EXPORT_SYMBOL_GPL(__cpufreq_driver_target); int cpufreq_driver_target(struct cpufreq_policy *policy, unsigned int target_freq, unsigned int relation) { int ret = -EINVAL; down_write(&policy->rwsem); ret = __cpufreq_driver_target(policy, target_freq, relation); up_write(&policy->rwsem); return ret; } EXPORT_SYMBOL_GPL(cpufreq_driver_target); __weak struct cpufreq_governor *cpufreq_fallback_governor(void) { return NULL; } static int cpufreq_init_governor(struct cpufreq_policy *policy) { int ret; /* Don't start any governor operations if we are entering suspend */ if (cpufreq_suspended) return 0; /* * Governor might not be initiated here if ACPI _PPC changed * notification happened, so check it. */ if (!policy->governor) return -EINVAL; /* Platform doesn't want dynamic frequency switching ? */ if (policy->governor->dynamic_switching && cpufreq_driver->flags & CPUFREQ_NO_AUTO_DYNAMIC_SWITCHING) { struct cpufreq_governor *gov = cpufreq_fallback_governor(); if (gov) { pr_warn("Can't use %s governor as dynamic switching is disallowed. Fallback to %s governor\n", policy->governor->name, gov->name); policy->governor = gov; } else { return -EINVAL; } } if (!try_module_get(policy->governor->owner)) return -EINVAL; pr_debug("%s: for CPU %u\n", __func__, policy->cpu); if (policy->governor->init) { ret = policy->governor->init(policy); if (ret) { module_put(policy->governor->owner); return ret; } } return 0; } static void cpufreq_exit_governor(struct cpufreq_policy *policy) { if (cpufreq_suspended || !policy->governor) return; pr_debug("%s: for CPU %u\n", __func__, policy->cpu); if (policy->governor->exit) policy->governor->exit(policy); module_put(policy->governor->owner); } static int cpufreq_start_governor(struct cpufreq_policy *policy) { int ret; if (cpufreq_suspended) return 0; if (!policy->governor) return -EINVAL; pr_debug("%s: for CPU %u\n", __func__, policy->cpu); if (cpufreq_driver->get && !cpufreq_driver->setpolicy) cpufreq_update_current_freq(policy); if (policy->governor->start) { ret = policy->governor->start(policy); if (ret) return ret; } if (policy->governor->limits) policy->governor->limits(policy); return 0; } static void cpufreq_stop_governor(struct cpufreq_policy *policy) { if (cpufreq_suspended || !policy->governor) return; pr_debug("%s: for CPU %u\n", __func__, policy->cpu); if (policy->governor->stop) policy->governor->stop(policy); } static void cpufreq_governor_limits(struct cpufreq_policy *policy) { if (cpufreq_suspended || !policy->governor) return; pr_debug("%s: for CPU %u\n", __func__, policy->cpu); if (policy->governor->limits) policy->governor->limits(policy); } int cpufreq_register_governor(struct cpufreq_governor *governor) { int err; if (!governor) return -EINVAL; if (cpufreq_disabled()) return -ENODEV; mutex_lock(&cpufreq_governor_mutex); err = -EBUSY; if (!find_governor(governor->name)) { err = 0; list_add(&governor->governor_list, &cpufreq_governor_list); } mutex_unlock(&cpufreq_governor_mutex); return err; } EXPORT_SYMBOL_GPL(cpufreq_register_governor); void cpufreq_unregister_governor(struct cpufreq_governor *governor) { struct cpufreq_policy *policy; unsigned long flags; if (!governor) return; if (cpufreq_disabled()) return; /* clear last_governor for all inactive policies */ read_lock_irqsave(&cpufreq_driver_lock, flags); for_each_inactive_policy(policy) { if (!strcmp(policy->last_governor, governor->name)) { policy->governor = NULL; strcpy(policy->last_governor, "\0"); } } read_unlock_irqrestore(&cpufreq_driver_lock, flags); mutex_lock(&cpufreq_governor_mutex); list_del(&governor->governor_list); mutex_unlock(&cpufreq_governor_mutex); } EXPORT_SYMBOL_GPL(cpufreq_unregister_governor); /********************************************************************* * POLICY INTERFACE * *********************************************************************/ /** * cpufreq_get_policy - get the current cpufreq_policy * @policy: struct cpufreq_policy into which the current cpufreq_policy * is written * * Reads the current cpufreq policy. */ int cpufreq_get_policy(struct cpufreq_policy *policy, unsigned int cpu) { struct cpufreq_policy *cpu_policy; if (!policy) return -EINVAL; cpu_policy = cpufreq_cpu_get(cpu); if (!cpu_policy) return -EINVAL; memcpy(policy, cpu_policy, sizeof(*policy)); cpufreq_cpu_put(cpu_policy); return 0; } EXPORT_SYMBOL(cpufreq_get_policy); /* * policy : current policy. * new_policy: policy to be set. */ static int cpufreq_set_policy(struct cpufreq_policy *policy, struct cpufreq_policy *new_policy) { struct cpufreq_governor *old_gov; int ret; pr_debug("setting new policy for CPU %u: %u - %u kHz\n", new_policy->cpu, new_policy->min, new_policy->max); memcpy(&new_policy->cpuinfo, &policy->cpuinfo, sizeof(policy->cpuinfo)); /* * This check works well when we store new min/max freq attributes, * because new_policy is a copy of policy with one field updated. */ if (new_policy->min > new_policy->max) return -EINVAL; /* verify the cpu speed can be set within this limit */ ret = cpufreq_driver->verify(new_policy); if (ret) return ret; /* adjust if necessary - all reasons */ blocking_notifier_call_chain(&cpufreq_policy_notifier_list, CPUFREQ_ADJUST, new_policy); /* * verify the cpu speed can be set within this limit, which might be * different to the first one */ ret = cpufreq_driver->verify(new_policy); if (ret) return ret; /* notification of the new policy */ blocking_notifier_call_chain(&cpufreq_policy_notifier_list, CPUFREQ_NOTIFY, new_policy); policy->min = new_policy->min; policy->max = new_policy->max; trace_cpu_frequency_limits(policy); policy->cached_target_freq = UINT_MAX; pr_debug("new min and max freqs are %u - %u kHz\n", policy->min, policy->max); if (cpufreq_driver->setpolicy) { policy->policy = new_policy->policy; pr_debug("setting range\n"); return cpufreq_driver->setpolicy(new_policy); } if (new_policy->governor == policy->governor) { pr_debug("cpufreq: governor limits update\n"); cpufreq_governor_limits(policy); return 0; } pr_debug("governor switch\n"); /* save old, working values */ old_gov = policy->governor; /* end old governor */ if (old_gov) { cpufreq_stop_governor(policy); cpufreq_exit_governor(policy); } /* start new governor */ policy->governor = new_policy->governor; ret = cpufreq_init_governor(policy); if (!ret) { ret = cpufreq_start_governor(policy); if (!ret) { pr_debug("cpufreq: governor change\n"); return 0; } cpufreq_exit_governor(policy); } /* new governor failed, so re-start old one */ pr_debug("starting governor %s failed\n", policy->governor->name); if (old_gov) { policy->governor = old_gov; if (cpufreq_init_governor(policy)) policy->governor = NULL; else cpufreq_start_governor(policy); } return ret; } /** * cpufreq_update_policy - re-evaluate an existing cpufreq policy * @cpu: CPU which shall be re-evaluated * * Useful for policy notifiers which have different necessities * at different times. */ void cpufreq_update_policy(unsigned int cpu) { struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); struct cpufreq_policy new_policy; if (!policy) return; down_write(&policy->rwsem); if (policy_is_inactive(policy)) goto unlock; pr_debug("updating policy for CPU %u\n", cpu); memcpy(&new_policy, policy, sizeof(*policy)); new_policy.min = policy->user_policy.min; new_policy.max = policy->user_policy.max; /* * BIOS might change freq behind our back * -> ask driver for current freq and notify governors about a change */ if (cpufreq_driver->get && !cpufreq_driver->setpolicy) { if (cpufreq_suspended) goto unlock; new_policy.cur = cpufreq_update_current_freq(policy); if (WARN_ON(!new_policy.cur)) goto unlock; } cpufreq_set_policy(policy, &new_policy); unlock: up_write(&policy->rwsem); cpufreq_cpu_put(policy); } EXPORT_SYMBOL(cpufreq_update_policy); /********************************************************************* * BOOST * *********************************************************************/ static int cpufreq_boost_set_sw(int state) { struct cpufreq_policy *policy; int ret = -EINVAL; for_each_active_policy(policy) { if (!policy->freq_table) continue; ret = cpufreq_frequency_table_cpuinfo(policy, policy->freq_table); if (ret) { pr_err("%s: Policy frequency update failed\n", __func__); break; } down_write(&policy->rwsem); policy->user_policy.max = policy->max; cpufreq_governor_limits(policy); up_write(&policy->rwsem); } return ret; } int cpufreq_boost_trigger_state(int state) { unsigned long flags; int ret = 0; if (cpufreq_driver->boost_enabled == state) return 0; write_lock_irqsave(&cpufreq_driver_lock, flags); cpufreq_driver->boost_enabled = state; write_unlock_irqrestore(&cpufreq_driver_lock, flags); ret = cpufreq_driver->set_boost(state); if (ret) { write_lock_irqsave(&cpufreq_driver_lock, flags); cpufreq_driver->boost_enabled = !state; write_unlock_irqrestore(&cpufreq_driver_lock, flags); pr_err("%s: Cannot %s BOOST\n", __func__, state ? "enable" : "disable"); } return ret; } static bool cpufreq_boost_supported(void) { return likely(cpufreq_driver) && cpufreq_driver->set_boost; } static int create_boost_sysfs_file(void) { int ret; ret = sysfs_create_file(cpufreq_global_kobject, &boost.attr); if (ret) pr_err("%s: cannot register global BOOST sysfs file\n", __func__); return ret; } static void remove_boost_sysfs_file(void) { if (cpufreq_boost_supported()) sysfs_remove_file(cpufreq_global_kobject, &boost.attr); } int cpufreq_enable_boost_support(void) { if (!cpufreq_driver) return -EINVAL; if (cpufreq_boost_supported()) return 0; cpufreq_driver->set_boost = cpufreq_boost_set_sw; /* This will get removed on driver unregister */ return create_boost_sysfs_file(); } EXPORT_SYMBOL_GPL(cpufreq_enable_boost_support); int cpufreq_boost_enabled(void) { return cpufreq_driver->boost_enabled; } EXPORT_SYMBOL_GPL(cpufreq_boost_enabled); /********************************************************************* * REGISTER / UNREGISTER CPUFREQ DRIVER * *********************************************************************/ static enum cpuhp_state hp_online; static int cpuhp_cpufreq_online(unsigned int cpu) { cpufreq_online(cpu); return 0; } static int cpuhp_cpufreq_offline(unsigned int cpu) { cpufreq_offline(cpu); return 0; } /** * cpufreq_register_driver - register a CPU Frequency driver * @driver_data: A struct cpufreq_driver containing the values# * submitted by the CPU Frequency driver. * * Registers a CPU Frequency driver to this core code. This code * returns zero on success, -EEXIST when another driver got here first * (and isn't unregistered in the meantime). * */ int cpufreq_register_driver(struct cpufreq_driver *driver_data) { unsigned long flags; int ret; if (cpufreq_disabled()) return -ENODEV; if (!driver_data || !driver_data->verify || !driver_data->init || !(driver_data->setpolicy || driver_data->target_index || driver_data->target) || (driver_data->setpolicy && (driver_data->target_index || driver_data->target)) || (!!driver_data->get_intermediate != !!driver_data->target_intermediate)) return -EINVAL; pr_debug("trying to register driver %s\n", driver_data->name); /* Protect against concurrent CPU online/offline. */ cpus_read_lock(); write_lock_irqsave(&cpufreq_driver_lock, flags); if (cpufreq_driver) { write_unlock_irqrestore(&cpufreq_driver_lock, flags); ret = -EEXIST; goto out; } cpufreq_driver = driver_data; write_unlock_irqrestore(&cpufreq_driver_lock, flags); if (driver_data->setpolicy) driver_data->flags |= CPUFREQ_CONST_LOOPS; if (cpufreq_boost_supported()) { ret = create_boost_sysfs_file(); if (ret) goto err_null_driver; } ret = subsys_interface_register(&cpufreq_interface); if (ret) goto err_boost_unreg; if (!(cpufreq_driver->flags & CPUFREQ_STICKY) && list_empty(&cpufreq_policy_list)) { /* if all ->init() calls failed, unregister */ ret = -ENODEV; pr_debug("%s: No CPU initialized for driver %s\n", __func__, driver_data->name); goto err_if_unreg; } ret = cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ONLINE_DYN, "cpufreq:online", cpuhp_cpufreq_online, cpuhp_cpufreq_offline); if (ret < 0) goto err_if_unreg; hp_online = ret; ret = 0; pr_debug("driver %s up and running\n", driver_data->name); goto out; err_if_unreg: subsys_interface_unregister(&cpufreq_interface); err_boost_unreg: remove_boost_sysfs_file(); err_null_driver: write_lock_irqsave(&cpufreq_driver_lock, flags); cpufreq_driver = NULL; write_unlock_irqrestore(&cpufreq_driver_lock, flags); out: cpus_read_unlock(); return ret; } EXPORT_SYMBOL_GPL(cpufreq_register_driver); /** * cpufreq_unregister_driver - unregister the current CPUFreq driver * * Unregister the current CPUFreq driver. Only call this if you have * the right to do so, i.e. if you have succeeded in initialising before! * Returns zero if successful, and -EINVAL if the cpufreq_driver is * currently not initialised. */ int cpufreq_unregister_driver(struct cpufreq_driver *driver) { unsigned long flags; if (!cpufreq_driver || (driver != cpufreq_driver)) return -EINVAL; pr_debug("unregistering driver %s\n", driver->name); /* Protect against concurrent cpu hotplug */ cpus_read_lock(); subsys_interface_unregister(&cpufreq_interface); remove_boost_sysfs_file(); cpuhp_remove_state_nocalls_cpuslocked(hp_online); write_lock_irqsave(&cpufreq_driver_lock, flags); cpufreq_driver = NULL; write_unlock_irqrestore(&cpufreq_driver_lock, flags); cpus_read_unlock(); return 0; } EXPORT_SYMBOL_GPL(cpufreq_unregister_driver); /* * Stop cpufreq at shutdown to make sure it isn't holding any locks * or mutexes when secondary CPUs are halted. */ static struct syscore_ops cpufreq_syscore_ops = { .shutdown = cpufreq_suspend, }; struct kobject *cpufreq_global_kobject; EXPORT_SYMBOL(cpufreq_global_kobject); static int __init cpufreq_core_init(void) { if (cpufreq_disabled()) return -ENODEV; cpufreq_global_kobject = kobject_create_and_add("cpufreq", &cpu_subsys.dev_root->kobj); BUG_ON(!cpufreq_global_kobject); register_syscore_ops(&cpufreq_syscore_ops); return 0; } module_param(off, int, 0444); core_initcall(cpufreq_core_init);
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