diff options
Diffstat (limited to 'drivers/cpufreq/cpufreq.c')
-rw-r--r-- | drivers/cpufreq/cpufreq.c | 218 |
1 files changed, 199 insertions, 19 deletions
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 8d19f7c06010..08ca8c9f41cd 100644 --- a/drivers/cpufreq/cpufreq.c +++ b/drivers/cpufreq/cpufreq.c @@ -39,7 +39,7 @@ static struct cpufreq_driver *cpufreq_driver; static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data); static DEFINE_PER_CPU(struct cpufreq_policy *, cpufreq_cpu_data_fallback); static DEFINE_RWLOCK(cpufreq_driver_lock); -static DEFINE_MUTEX(cpufreq_governor_lock); +DEFINE_MUTEX(cpufreq_governor_lock); static LIST_HEAD(cpufreq_policy_list); #ifdef CONFIG_HOTPLUG_CPU @@ -176,6 +176,20 @@ int cpufreq_generic_init(struct cpufreq_policy *policy, } EXPORT_SYMBOL_GPL(cpufreq_generic_init); +unsigned int cpufreq_generic_get(unsigned int cpu) +{ + struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, 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); + struct cpufreq_policy *cpufreq_cpu_get(unsigned int cpu) { struct cpufreq_policy *policy = NULL; @@ -320,10 +334,51 @@ void cpufreq_notify_transition(struct cpufreq_policy *policy, } EXPORT_SYMBOL_GPL(cpufreq_notify_transition); +/* Do post notifications when there are chances that transition has failed */ +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); +} +EXPORT_SYMBOL_GPL(cpufreq_notify_post_transition); + /********************************************************************* * SYSFS INTERFACE * *********************************************************************/ +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) { @@ -929,6 +984,9 @@ static void cpufreq_policy_put_kobj(struct cpufreq_policy *policy) struct kobject *kobj; struct completion *cmp; + blocking_notifier_call_chain(&cpufreq_policy_notifier_list, + CPUFREQ_REMOVE_POLICY, policy); + down_read(&policy->rwsem); kobj = &policy->kobj; cmp = &policy->kobj_unregister; @@ -1051,6 +1109,11 @@ static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif, goto err_set_policy_cpu; } + write_lock_irqsave(&cpufreq_driver_lock, flags); + for_each_cpu(j, policy->cpus) + per_cpu(cpufreq_cpu_data, j) = policy; + write_unlock_irqrestore(&cpufreq_driver_lock, flags); + if (cpufreq_driver->get) { policy->cur = cpufreq_driver->get(policy->cpu); if (!policy->cur) { @@ -1059,6 +1122,46 @@ static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif, } } + /* + * 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); + } + } + /* related cpus should atleast have policy->cpus */ cpumask_or(policy->related_cpus, policy->related_cpus, policy->cpus); @@ -1085,15 +1188,12 @@ static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif, } #endif - write_lock_irqsave(&cpufreq_driver_lock, flags); - for_each_cpu(j, policy->cpus) - per_cpu(cpufreq_cpu_data, j) = policy; - write_unlock_irqrestore(&cpufreq_driver_lock, flags); - if (!frozen) { ret = cpufreq_add_dev_interface(policy, dev); if (ret) goto err_out_unregister; + blocking_notifier_call_chain(&cpufreq_policy_notifier_list, + CPUFREQ_CREATE_POLICY, policy); } write_lock_irqsave(&cpufreq_driver_lock, flags); @@ -1115,12 +1215,12 @@ static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif, return 0; err_out_unregister: +err_get_freq: write_lock_irqsave(&cpufreq_driver_lock, flags); for_each_cpu(j, policy->cpus) per_cpu(cpufreq_cpu_data, j) = NULL; write_unlock_irqrestore(&cpufreq_driver_lock, flags); -err_get_freq: if (cpufreq_driver->exit) cpufreq_driver->exit(policy); err_set_policy_cpu: @@ -1725,17 +1825,8 @@ int __cpufreq_driver_target(struct cpufreq_policy *policy, pr_err("%s: Failed to change cpu frequency: %d\n", __func__, retval); - if (notify) { - /* - * Notify with old freq in case we failed to change - * frequency - */ - if (retval) - freqs.new = freqs.old; - - cpufreq_notify_transition(policy, &freqs, - CPUFREQ_POSTCHANGE); - } + if (notify) + cpufreq_notify_post_transition(policy, &freqs, retval); } out: @@ -2120,6 +2211,73 @@ static struct notifier_block __refdata cpufreq_cpu_notifier = { }; /********************************************************************* + * BOOST * + *********************************************************************/ +static int cpufreq_boost_set_sw(int state) +{ + struct cpufreq_frequency_table *freq_table; + struct cpufreq_policy *policy; + int ret = -EINVAL; + + list_for_each_entry(policy, &cpufreq_policy_list, policy_list) { + freq_table = cpufreq_frequency_get_table(policy->cpu); + if (freq_table) { + ret = cpufreq_frequency_table_cpuinfo(policy, + freq_table); + if (ret) { + pr_err("%s: Policy frequency update failed\n", + __func__); + break; + } + policy->user_policy.max = policy->max; + __cpufreq_governor(policy, CPUFREQ_GOV_LIMITS); + } + } + + 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; +} + +int cpufreq_boost_supported(void) +{ + if (likely(cpufreq_driver)) + return cpufreq_driver->boost_supported; + + return 0; +} +EXPORT_SYMBOL_GPL(cpufreq_boost_supported); + +int cpufreq_boost_enabled(void) +{ + return cpufreq_driver->boost_enabled; +} +EXPORT_SYMBOL_GPL(cpufreq_boost_enabled); + +/********************************************************************* * REGISTER / UNREGISTER CPUFREQ DRIVER * *********************************************************************/ @@ -2159,9 +2317,25 @@ int cpufreq_register_driver(struct cpufreq_driver *driver_data) cpufreq_driver = driver_data; write_unlock_irqrestore(&cpufreq_driver_lock, flags); + if (cpufreq_boost_supported()) { + /* + * Check if driver provides function to enable boost - + * if not, use cpufreq_boost_set_sw as default + */ + if (!cpufreq_driver->set_boost) + cpufreq_driver->set_boost = cpufreq_boost_set_sw; + + ret = cpufreq_sysfs_create_file(&boost.attr); + if (ret) { + pr_err("%s: cannot register global BOOST sysfs file\n", + __func__); + goto err_null_driver; + } + } + ret = subsys_interface_register(&cpufreq_interface); if (ret) - goto err_null_driver; + goto err_boost_unreg; if (!(cpufreq_driver->flags & CPUFREQ_STICKY)) { int i; @@ -2188,6 +2362,9 @@ int cpufreq_register_driver(struct cpufreq_driver *driver_data) return 0; err_if_unreg: subsys_interface_unregister(&cpufreq_interface); +err_boost_unreg: + if (cpufreq_boost_supported()) + cpufreq_sysfs_remove_file(&boost.attr); err_null_driver: write_lock_irqsave(&cpufreq_driver_lock, flags); cpufreq_driver = NULL; @@ -2214,6 +2391,9 @@ int cpufreq_unregister_driver(struct cpufreq_driver *driver) pr_debug("unregistering driver %s\n", driver->name); subsys_interface_unregister(&cpufreq_interface); + if (cpufreq_boost_supported()) + cpufreq_sysfs_remove_file(&boost.attr); + unregister_hotcpu_notifier(&cpufreq_cpu_notifier); down_write(&cpufreq_rwsem); |