Signed-off-by: Aaron Wu <aaron.wu@xxxxxxxxxx> Remove Blackfin CPU frequency support --- drivers/cpufreq/Makefile | 1 - drivers/cpufreq/blackfin-cpufreq.c | 217 --- drivers/cpufreq/cpufreq.c | 2612 ------------------------------------ 3 files changed, 2830 deletions(-) delete mode 100644 drivers/cpufreq/blackfin-cpufreq.c delete mode 100644 drivers/cpufreq/cpufreq.c diff --git a/drivers/cpufreq/Makefile b/drivers/cpufreq/Makefile index c60c1e1..43e4254 100644 --- a/drivers/cpufreq/Makefile +++ b/drivers/cpufreq/Makefile @@ -100,7 +100,6 @@ obj-$(CONFIG_POWERNV_CPUFREQ) += powernv-cpufreq.o ################################################################################## # Other platform drivers -obj-$(CONFIG_BFIN_CPU_FREQ) += blackfin-cpufreq.o obj-$(CONFIG_BMIPS_CPUFREQ) += bmips-cpufreq.o obj-$(CONFIG_CRIS_MACH_ARTPEC3) += cris-artpec3-cpufreq.o obj-$(CONFIG_ETRAXFS) += cris-etraxfs-cpufreq.o diff --git a/drivers/cpufreq/blackfin-cpufreq.c b/drivers/cpufreq/blackfin-cpufreq.c deleted file mode 100644 index 12e97d8..0000000 --- a/drivers/cpufreq/blackfin-cpufreq.c +++ /dev/null @@ -1,217 +0,0 @@ -/* - * Blackfin core clock scaling - * - * Copyright 2008-2011 Analog Devices Inc. - * - * Licensed under the GPL-2 or later. - */ - -#include <linux/kernel.h> -#include <linux/module.h> -#include <linux/types.h> -#include <linux/init.h> -#include <linux/clk.h> -#include <linux/cpufreq.h> -#include <linux/fs.h> -#include <linux/delay.h> -#include <asm/blackfin.h> -#include <asm/time.h> -#include <asm/dpmc.h> - - -/* this is the table of CCLK frequencies, in Hz */ -/* .driver_data is the entry in the auxiliary dpm_state_table[] */ -static struct cpufreq_frequency_table bfin_freq_table[] = { - { - .frequency = CPUFREQ_TABLE_END, - .driver_data = 0, - }, - { - .frequency = CPUFREQ_TABLE_END, - .driver_data = 1, - }, - { - .frequency = CPUFREQ_TABLE_END, - .driver_data = 2, - }, - { - .frequency = CPUFREQ_TABLE_END, - .driver_data = 0, - }, -}; - -static struct bfin_dpm_state { - unsigned int csel; /* system clock divider */ - unsigned int tscale; /* change the divider on the core timer interrupt */ -} dpm_state_table[3]; - -#if defined(CONFIG_CYCLES_CLOCKSOURCE) -/* - * normalized to maximum frequency offset for CYCLES, - * used in time-ts cycles clock source, but could be used - * somewhere also. - */ -unsigned long long __bfin_cycles_off; -unsigned int __bfin_cycles_mod; -#endif - -/**************************************************************************/ -static void __init bfin_init_tables(unsigned long cclk, unsigned long sclk) -{ - - unsigned long csel, min_cclk; - int index; - - /* Anomaly 273 seems to still exist on non-BF54x w/dcache turned on */ -#if ANOMALY_05000273 || ANOMALY_05000274 || \ - (!(defined(CONFIG_BF54x) || defined(CONFIG_BF60x)) \ - && defined(CONFIG_BFIN_EXTMEM_DCACHEABLE)) - min_cclk = sclk * 2; -#else - min_cclk = sclk; -#endif - -#ifndef CONFIG_BF60x - csel = ((bfin_read_PLL_DIV() & CSEL) >> 4); -#else - csel = bfin_read32(CGU0_DIV) & 0x1F; -#endif - - for (index = 0; (cclk >> index) >= min_cclk && csel <= 3 && index < 3; index++, csel++) { - bfin_freq_table[index].frequency = cclk >> index; -#ifndef CONFIG_BF60x - dpm_state_table[index].csel = csel << 4; /* Shift now into PLL_DIV bitpos */ -#else - dpm_state_table[index].csel = csel; -#endif - dpm_state_table[index].tscale = (TIME_SCALE >> index) - 1; - - pr_debug("cpufreq: freq:%d csel:0x%x tscale:%d\n", - bfin_freq_table[index].frequency, - dpm_state_table[index].csel, - dpm_state_table[index].tscale); - } - return; -} - -static void bfin_adjust_core_timer(void *info) -{ - unsigned int tscale; - unsigned int index = *(unsigned int *)info; - - /* we have to adjust the core timer, because it is using cclk */ - tscale = dpm_state_table[index].tscale; - bfin_write_TSCALE(tscale); - return; -} - -static unsigned int bfin_getfreq_khz(unsigned int cpu) -{ - /* Both CoreA/B have the same core clock */ - return get_cclk() / 1000; -} - -#ifdef CONFIG_BF60x -static int cpu_set_cclk(int cpu, unsigned long new) -{ - struct clk *clk; - int ret; - - clk = clk_get(NULL, "CCLK"); - if (IS_ERR(clk)) - return -ENODEV; - - ret = clk_set_rate(clk, new); - clk_put(clk); - return ret; -} -#endif - -static int bfin_target(struct cpufreq_policy *policy, unsigned int index) -{ -#ifndef CONFIG_BF60x - unsigned int plldiv; -#endif - static unsigned long lpj_ref; - static unsigned int lpj_ref_freq; - unsigned int old_freq, new_freq; - int ret = 0; - -#if defined(CONFIG_CYCLES_CLOCKSOURCE) - cycles_t cycles; -#endif - - old_freq = bfin_getfreq_khz(0); - new_freq = bfin_freq_table[index].frequency; - -#ifndef CONFIG_BF60x - plldiv = (bfin_read_PLL_DIV() & SSEL) | dpm_state_table[index].csel; - bfin_write_PLL_DIV(plldiv); -#else - ret = cpu_set_cclk(policy->cpu, new_freq * 1000); - if (ret != 0) { - WARN_ONCE(ret, "cpufreq set freq failed %d\n", ret); - return ret; - } -#endif - on_each_cpu(bfin_adjust_core_timer, &index, 1); -#if defined(CONFIG_CYCLES_CLOCKSOURCE) - cycles = get_cycles(); - SSYNC(); - cycles += 10; /* ~10 cycles we lose after get_cycles() */ - __bfin_cycles_off += (cycles << __bfin_cycles_mod) - (cycles << index); - __bfin_cycles_mod = index; -#endif - if (!lpj_ref_freq) { - lpj_ref = loops_per_jiffy; - lpj_ref_freq = old_freq; - } - if (new_freq != old_freq) { - loops_per_jiffy = cpufreq_scale(lpj_ref, - lpj_ref_freq, new_freq); - } - - return ret; -} - -static int __bfin_cpu_init(struct cpufreq_policy *policy) -{ - - unsigned long cclk, sclk; - - cclk = get_cclk() / 1000; - sclk = get_sclk() / 1000; - - if (policy->cpu == CPUFREQ_CPU) - bfin_init_tables(cclk, sclk); - - policy->cpuinfo.transition_latency = 50000; /* 50us assumed */ - - return cpufreq_table_validate_and_show(policy, bfin_freq_table); -} - -static struct cpufreq_driver bfin_driver = { - .verify = cpufreq_generic_frequency_table_verify, - .target_index = bfin_target, - .get = bfin_getfreq_khz, - .init = __bfin_cpu_init, - .name = "bfin cpufreq", - .attr = cpufreq_generic_attr, -}; - -static int __init bfin_cpu_init(void) -{ - return cpufreq_register_driver(&bfin_driver); -} - -static void __exit bfin_cpu_exit(void) -{ - cpufreq_unregister_driver(&bfin_driver); -} - -MODULE_AUTHOR("Michael Hennerich <hennerich@xxxxxxxxxxxxxxxxxxxx>"); -MODULE_DESCRIPTION("cpufreq driver for Blackfin"); -MODULE_LICENSE("GPL"); - -module_init(bfin_cpu_init); -module_exit(bfin_cpu_exit); diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c deleted file mode 100644 index de33ebf..0000000 --- a/drivers/cpufreq/cpufreq.c +++ /dev/null @@ -1,2612 +0,0 @@ -/* - * linux/drivers/cpufreq/cpufreq.c - * - * Copyright (C) 2001 Russell King - * (C) 2002 - 2003 Dominik Brodowski <linux@xxxxxxxx> - * (C) 2013 Viresh Kumar <viresh.kumar@xxxxxxxxxx> - * - * Oct 2005 - Ashok Raj <ashok.raj@xxxxxxxxx> - * Added handling for CPU hotplug - * Feb 2006 - Jacob Shin <jacob.shin@xxxxxxx> - * 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); -static struct srcu_notifier_head cpufreq_transition_notifier_list; - -static bool init_cpufreq_transition_notifier_list_called; -static int __init init_cpufreq_transition_notifier_list(void) -{ - srcu_init_notifier_head(&cpufreq_transition_notifier_list); - init_cpufreq_transition_notifier_list_called = true; - return 0; -} -pure_initcall(init_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) -{ - int ret; - - ret = cpufreq_table_validate_and_show(policy, table); - if (ret) { - pr_err("%s: invalid frequency table: %d\n", __func__, ret); - return ret; - } - - 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 -} - -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) && (policy->cpu == freqs->cpu) && - (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; - } - } - 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: %lu - CPU: %lu\n", - (unsigned long)freqs->new, (unsigned long)freqs->cpu); - trace_cpu_frequency(freqs->new, freqs->cpu); - cpufreq_stats_record_transition(policy, freqs->new); - srcu_notifier_call_chain(&cpufreq_transition_notifier_list, - CPUFREQ_POSTCHANGE, freqs); - if (likely(policy) && likely(policy->cpu == freqs->cpu)) - policy->cur = freqs->new; - break; - } -} - -/** - * cpufreq_notify_transition - call notifier chain and adjust_jiffies - * on frequency transition. - * - * 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) -{ - for_each_cpu(freqs->cpu, policy->cpus) - __cpufreq_notify_transition(policy, freqs, state); -} - -/* Do post notifications when there are chances that transition has failed */ -static void cpufreq_notify_post_transition(struct cpufreq_policy *policy, - struct cpufreq_freqs *freqs, int transition_failed) -{ - cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); - if (!transition_failed) - return; - - swap(freqs->old, freqs->new); - cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); - cpufreq_notify_transition(policy, freqs, CPUFREQ_POSTCHANGE); -} - -void cpufreq_freq_transition_begin(struct cpufreq_policy *policy, - struct cpufreq_freqs *freqs) -{ - - /* - * Catch double invocations of _begin() which lead to self-deadlock. - * ASYNC_NOTIFICATION drivers are left out because the cpufreq core - * doesn't invoke _begin() on their behalf, and hence the chances of - * double invocations are very low. Moreover, there are scenarios - * where these checks can emit false-positive warnings in these - * drivers; so we avoid that by skipping them altogether. - */ - WARN_ON(!(cpufreq_driver->flags & CPUFREQ_ASYNC_NOTIFICATION) - && current == policy->transition_task); - -wait: - wait_event(policy->transition_wait, !policy->transition_ongoing); - - spin_lock(&policy->transition_lock); - - if (unlikely(policy->transition_ongoing)) { - spin_unlock(&policy->transition_lock); - goto wait; - } - - policy->transition_ongoing = true; - policy->transition_task = current; - - spin_unlock(&policy->transition_lock); - - cpufreq_notify_transition(policy, freqs, CPUFREQ_PRECHANGE); -} -EXPORT_SYMBOL_GPL(cpufreq_freq_transition_begin); - -void cpufreq_freq_transition_end(struct cpufreq_policy *policy, - struct cpufreq_freqs *freqs, int transition_failed) -{ - if (unlikely(WARN_ON(!policy->transition_ongoing))) - return; - - cpufreq_notify_post_transition(policy, freqs, transition_failed); - - policy->transition_ongoing = false; - policy->transition_task = NULL; - - wake_up(&policy->transition_wait); -} -EXPORT_SYMBOL_GPL(cpufreq_freq_transition_end); - -/* - * Fast frequency switching status count. Positive means "enabled", negative - * means "disabled" and 0 means "not decided yet". - */ -static int cpufreq_fast_switch_count; -static DEFINE_MUTEX(cpufreq_fast_switch_lock); - -static void cpufreq_list_transition_notifiers(void) -{ - struct notifier_block *nb; - - pr_info("Registered transition notifiers:\n"); - - mutex_lock(&cpufreq_transition_notifier_list.mutex); - - for (nb = cpufreq_transition_notifier_list.head; nb; nb = nb->next) - pr_info("%pF\n", nb->notifier_call); - - mutex_unlock(&cpufreq_transition_notifier_list.mutex); -} - -/** - * cpufreq_enable_fast_switch - Enable fast frequency switching for policy. - * @policy: cpufreq policy to enable fast frequency switching for. - * - * Try to enable fast frequency switching for @policy. - * - * The attempt will fail if there is at least one transition notifier registered - * at this point, as fast frequency switching is quite fundamentally at odds - * with transition notifiers. Thus if successful, it will make registration of - * transition notifiers fail going forward. - */ -void cpufreq_enable_fast_switch(struct cpufreq_policy *policy) -{ - lockdep_assert_held(&policy->rwsem); - - if (!policy->fast_switch_possible) - return; - - mutex_lock(&cpufreq_fast_switch_lock); - if (cpufreq_fast_switch_count >= 0) { - cpufreq_fast_switch_count++; - policy->fast_switch_enabled = true; - } else { - pr_warn("CPU%u: Fast frequency switching not enabled\n", - policy->cpu); - cpufreq_list_transition_notifiers(); - } - mutex_unlock(&cpufreq_fast_switch_lock); -} -EXPORT_SYMBOL_GPL(cpufreq_enable_fast_switch); - -/** - * cpufreq_disable_fast_switch - Disable fast frequency switching for policy. - * @policy: cpufreq policy to disable fast frequency switching for. - */ -void cpufreq_disable_fast_switch(struct cpufreq_policy *policy) -{ - mutex_lock(&cpufreq_fast_switch_lock); - if (policy->fast_switch_enabled) { - policy->fast_switch_enabled = false; - if (!WARN_ON(cpufreq_fast_switch_count <= 0)) - cpufreq_fast_switch_count--; - } - mutex_unlock(&cpufreq_fast_switch_lock); -} -EXPORT_SYMBOL_GPL(cpufreq_disable_fast_switch); - -/** - * cpufreq_driver_resolve_freq - Map a target frequency to a driver-supported - * one. - * @target_freq: target frequency to resolve. - * - * The target to driver frequency mapping is cached in the policy. - * - * Return: Lowest driver-supported frequency greater than or equal to the - * given target_freq, subject to policy (min/max) and driver limitations. - */ -unsigned int cpufreq_driver_resolve_freq(struct cpufreq_policy *policy, - unsigned int target_freq) -{ - target_freq = clamp_val(target_freq, policy->min, policy->max); - policy->cached_target_freq = target_freq; - - if (cpufreq_driver->target_index) { - int idx; - - idx = cpufreq_frequency_table_target(policy, target_freq, - CPUFREQ_RELATION_L); - policy->cached_resolved_idx = idx; - return policy->freq_table[idx].frequency; - } - - if (cpufreq_driver->resolve_freq) - return cpufreq_driver->resolve_freq(policy, target_freq); - - return target_freq; -} -EXPORT_SYMBOL_GPL(cpufreq_driver_resolve_freq); - -unsigned int cpufreq_policy_transition_delay_us(struct cpufreq_policy *policy) -{ - unsigned int latency; - - if (policy->transition_delay_us) - return policy->transition_delay_us; - - latency = policy->cpuinfo.transition_latency / NSEC_PER_USEC; - if (latency) { - /* - * For platforms that can change the frequency very fast (< 10 - * us), the above formula gives a decent transition delay. But - * for platforms where transition_latency is in milliseconds, it - * ends up giving unrealistic values. - * - * Cap the default transition delay to 10 ms, which seems to be - * a reasonable amount of time after which we should reevaluate - * the frequency. - */ - return min(latency * LATENCY_MULTIPLIER, (unsigned int)10000); - } - - return LATENCY_MULTIPLIER; -} -EXPORT_SYMBOL_GPL(cpufreq_policy_transition_delay_us); - -/********************************************************************* - * SYSFS INTERFACE * - *********************************************************************/ -static ssize_t show_boost(struct kobject *kobj, - struct attribute *attr, char *buf) -{ - return sprintf(buf, "%d\n", cpufreq_driver->boost_enabled); -} - -static ssize_t store_boost(struct kobject *kobj, struct attribute *attr, - const char *buf, size_t count) -{ - int ret, enable; - - ret = sscanf(buf, "%d", &enable); - if (ret != 1 || enable < 0 || enable > 1) - return -EINVAL; - - if (cpufreq_boost_trigger_state(enable)) { - pr_err("%s: Cannot %s BOOST!\n", - __func__, enable ? "enable" : "disable"); - return -EINVAL; - } - - pr_debug("%s: cpufreq BOOST %s\n", - __func__, enable ? "enabled" : "disabled"); - - return count; -} -define_one_global_rw(boost); - -static struct cpufreq_governor *find_governor(const char *str_governor) -{ - struct cpufreq_governor *t; - - for_each_governor(t) - if (!strncasecmp(str_governor, t->name, CPUFREQ_NAME_LEN)) - return t; - - return NULL; -} - -/** - * cpufreq_parse_governor - parse a governor string - */ -static int cpufreq_parse_governor(char *str_governor, - struct cpufreq_policy *policy) -{ - if (cpufreq_driver->setpolicy) { - if (!strncasecmp(str_governor, "performance", CPUFREQ_NAME_LEN)) { - policy->policy = CPUFREQ_POLICY_PERFORMANCE; - return 0; - } - - if (!strncasecmp(str_governor, "powersave", CPUFREQ_NAME_LEN)) { - policy->policy = CPUFREQ_POLICY_POWERSAVE; - return 0; - } - } else { - struct cpufreq_governor *t; - - mutex_lock(&cpufreq_governor_mutex); - - t = find_governor(str_governor); - if (!t) { - int ret; - - mutex_unlock(&cpufreq_governor_mutex); - - ret = request_module("cpufreq_%s", str_governor); - if (ret) - return -EINVAL; - - mutex_lock(&cpufreq_governor_mutex); - - t = find_governor(str_governor); - } - if (t && !try_module_get(t->owner)) - t = NULL; - - mutex_unlock(&cpufreq_governor_mutex); - - if (t) { - policy->governor = t; - return 0; - } - } - - return -EINVAL; -} - -/** - * cpufreq_per_cpu_attr_read() / show_##file_name() - - * print out cpufreq information - * - * Write out information from cpufreq_driver->policy[cpu]; object must be - * "unsigned int". - */ - -#define show_one(file_name, object) \ -static ssize_t show_##file_name \ -(struct cpufreq_policy *policy, char *buf) \ -{ \ - return sprintf(buf, "%u\n", policy->object); \ -} - -show_one(cpuinfo_min_freq, cpuinfo.min_freq); -show_one(cpuinfo_max_freq, cpuinfo.max_freq); -show_one(cpuinfo_transition_latency, cpuinfo.transition_latency); -show_one(scaling_min_freq, min); -show_one(scaling_max_freq, max); - -__weak unsigned int arch_freq_get_on_cpu(int cpu) -{ - return 0; -} - -static ssize_t show_scaling_cur_freq(struct cpufreq_policy *policy, char *buf) -{ - ssize_t ret; - unsigned int freq; - - freq = arch_freq_get_on_cpu(policy->cpu); - if (freq) - ret = sprintf(buf, "%u\n", freq); - else if (cpufreq_driver && cpufreq_driver->setpolicy && - cpufreq_driver->get) - ret = sprintf(buf, "%u\n", cpufreq_driver->get(policy->cpu)); - else - ret = sprintf(buf, "%u\n", policy->cur); - return ret; -} - -static int cpufreq_set_policy(struct cpufreq_policy *policy, - struct cpufreq_policy *new_policy); - -/** - * cpufreq_per_cpu_attr_write() / store_##file_name() - sysfs write access - */ -#define store_one(file_name, object) \ -static ssize_t store_##file_name \ -(struct cpufreq_policy *policy, const char *buf, size_t count) \ -{ \ - int ret, temp; \ - struct cpufreq_policy new_policy; \ - \ - memcpy(&new_policy, policy, sizeof(*policy)); \ - \ - 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_lock(); - - 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; - } - - 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_exit_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_exit_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_exit_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_exit_policy: - up_write(&policy->rwsem); - - if (cpufreq_driver->exit) - cpufreq_driver->exit(policy); - - for_each_cpu(j, policy->real_cpus) - remove_cpu_dev_symlink(policy, get_cpu_device(j)); - -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; - - WARN_ON(!init_cpufreq_transition_notifier_list_called); - - 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; - - 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); -- 2.7.4