diff options
Diffstat (limited to 'drivers/cpufreq/cpufreq.c')
| -rw-r--r-- | drivers/cpufreq/cpufreq.c | 364 |
1 files changed, 276 insertions, 88 deletions
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c index 02d534da22dd..199b52b7c3e1 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) { @@ -828,14 +883,17 @@ static void cpufreq_init_policy(struct cpufreq_policy *policy) int ret = 0; memcpy(&new_policy, policy, sizeof(*policy)); + + /* Use the default policy if its valid. */ + if (cpufreq_driver->setpolicy) + cpufreq_parse_governor(policy->governor->name, + &new_policy.policy, NULL); + /* assure that the starting sequence is run in cpufreq_set_policy */ policy->governor = NULL; /* set default policy */ ret = cpufreq_set_policy(policy, &new_policy); - policy->user_policy.policy = policy->policy; - policy->user_policy.governor = policy->governor; - if (ret) { pr_debug("setting policy failed\n"); if (cpufreq_driver->exit) @@ -845,8 +903,7 @@ static void cpufreq_init_policy(struct cpufreq_policy *policy) #ifdef CONFIG_HOTPLUG_CPU static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, - unsigned int cpu, struct device *dev, - bool frozen) + unsigned int cpu, struct device *dev) { int ret = 0; unsigned long flags; @@ -877,11 +934,7 @@ static int cpufreq_add_policy_cpu(struct cpufreq_policy *policy, } } - /* Don't touch sysfs links during light-weight init */ - if (!frozen) - ret = sysfs_create_link(&dev->kobj, &policy->kobj, "cpufreq"); - - return ret; + return sysfs_create_link(&dev->kobj, &policy->kobj, "cpufreq"); } #endif @@ -926,6 +979,30 @@ err_free_policy: return NULL; } +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; + up_read(&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) { free_cpumask_var(policy->related_cpus); @@ -986,7 +1063,7 @@ static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif, list_for_each_entry(tpolicy, &cpufreq_policy_list, policy_list) { if (cpumask_test_cpu(cpu, tpolicy->related_cpus)) { read_unlock_irqrestore(&cpufreq_driver_lock, flags); - ret = cpufreq_add_policy_cpu(tpolicy, cpu, dev, frozen); + ret = cpufreq_add_policy_cpu(tpolicy, cpu, dev); up_read(&cpufreq_rwsem); return ret; } @@ -994,15 +1071,17 @@ static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif, read_unlock_irqrestore(&cpufreq_driver_lock, flags); #endif - if (frozen) - /* Restore the saved policy when doing light-weight init */ - policy = cpufreq_policy_restore(cpu); - else + /* + * Restore the saved policy when doing light-weight init and fall back + * to the full init if that fails. + */ + policy = frozen ? cpufreq_policy_restore(cpu) : NULL; + if (!policy) { + frozen = false; policy = cpufreq_policy_alloc(); - - if (!policy) - goto nomem_out; - + if (!policy) + goto nomem_out; + } /* * In the resume path, since we restore a saved policy, the assignment @@ -1030,7 +1109,27 @@ static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif, goto err_set_policy_cpu; } - if (cpufreq_driver->get) { + /* related cpus should atleast have policy->cpus */ + cpumask_or(policy->related_cpus, 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 (!frozen) { + policy->user_policy.min = policy->min; + policy->user_policy.max = policy->max; + } + + down_write(&policy->rwsem); + 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 && !cpufreq_driver->setpolicy) { policy->cur = cpufreq_driver->get(policy->cpu); if (!policy->cur) { pr_err("%s: ->get() failed\n", __func__); @@ -1038,17 +1137,45 @@ static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif, } } - /* related cpus should atleast have policy->cpus */ - cpumask_or(policy->related_cpus, policy->related_cpus, policy->cpus); - /* - * affected cpus must always be the one, which are online. We aren't - * managing offline cpus here. + * 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. */ - cpumask_and(policy->cpus, policy->cpus, cpu_online_mask); + 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); - policy->user_policy.min = policy->min; - policy->user_policy.max = policy->max; + /* + * 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); + } + } blocking_notifier_call_chain(&cpufreq_policy_notifier_list, CPUFREQ_START, policy); @@ -1062,15 +1189,12 @@ 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); @@ -1079,6 +1203,12 @@ static int __cpufreq_add_dev(struct device *dev, struct subsys_interface *sif, cpufreq_init_policy(policy); + if (!frozen) { + policy->user_policy.policy = policy->policy; + policy->user_policy.governor = policy->governor; + } + up_write(&policy->rwsem); + kobject_uevent(&policy->kobj, KOBJ_ADD); up_read(&cpufreq_rwsem); @@ -1087,16 +1217,22 @@ 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: + if (frozen) { + /* Do not leave stale fallback data behind. */ + per_cpu(cpufreq_cpu_data_fallback, cpu) = NULL; + cpufreq_policy_put_kobj(policy); + } cpufreq_policy_free(policy); + nomem_out: up_read(&cpufreq_rwsem); @@ -1118,7 +1254,7 @@ static int cpufreq_add_dev(struct device *dev, struct subsys_interface *sif) } static int cpufreq_nominate_new_policy_cpu(struct cpufreq_policy *policy, - unsigned int old_cpu, bool frozen) + unsigned int old_cpu) { struct device *cpu_dev; int ret; @@ -1126,10 +1262,6 @@ static int cpufreq_nominate_new_policy_cpu(struct cpufreq_policy *policy, /* first sibling now owns the new sysfs dir */ cpu_dev = get_cpu_device(cpumask_any_but(policy->cpus, old_cpu)); - /* Don't touch sysfs files during light-weight tear-down */ - if (frozen) - return cpu_dev->id; - sysfs_remove_link(&cpu_dev->kobj, "cpufreq"); ret = kobject_move(&policy->kobj, &cpu_dev->kobj); if (ret) { @@ -1193,10 +1325,9 @@ static int __cpufreq_remove_dev_prepare(struct device *dev, up_read(&policy->rwsem); if (cpu != policy->cpu) { - if (!frozen) - sysfs_remove_link(&dev->kobj, "cpufreq"); + sysfs_remove_link(&dev->kobj, "cpufreq"); } else if (cpus > 1) { - new_cpu = cpufreq_nominate_new_policy_cpu(policy, cpu, frozen); + new_cpu = cpufreq_nominate_new_policy_cpu(policy, cpu); if (new_cpu >= 0) { update_policy_cpu(policy, new_cpu); @@ -1218,8 +1349,6 @@ static int __cpufreq_remove_dev_finish(struct device *dev, int ret; unsigned long flags; struct cpufreq_policy *policy; - struct kobject *kobj; - struct completion *cmp; read_lock_irqsave(&cpufreq_driver_lock, flags); policy = per_cpu(cpufreq_cpu_data, cpu); @@ -1249,22 +1378,8 @@ static int __cpufreq_remove_dev_finish(struct device *dev, } } - if (!frozen) { - down_read(&policy->rwsem); - kobj = &policy->kobj; - cmp = &policy->kobj_unregister; - up_read(&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"); - } + if (!frozen) + cpufreq_policy_put_kobj(policy); /* * Perform the ->exit() even during light-weight tear-down, @@ -1433,23 +1548,16 @@ static unsigned int __cpufreq_get(unsigned int cpu) */ unsigned int cpufreq_get(unsigned int cpu) { - struct cpufreq_policy *policy = per_cpu(cpufreq_cpu_data, cpu); + struct cpufreq_policy *policy = cpufreq_cpu_get(cpu); unsigned int ret_freq = 0; - if (cpufreq_disabled() || !cpufreq_driver) - return -ENOENT; - - BUG_ON(!policy); - - if (!down_read_trylock(&cpufreq_rwsem)) - return 0; - - down_read(&policy->rwsem); - - ret_freq = __cpufreq_get(cpu); + if (policy) { + down_read(&policy->rwsem); + ret_freq = __cpufreq_get(cpu); + up_read(&policy->rwsem); - up_read(&policy->rwsem); - up_read(&cpufreq_rwsem); + cpufreq_cpu_put(policy); + } return ret_freq; } @@ -1711,17 +1819,8 @@ 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: @@ -2044,7 +2143,7 @@ int cpufreq_update_policy(unsigned int cpu) * BIOS might change freq behind our back * -> ask driver for current freq and notify governors about a change */ - if (cpufreq_driver->get) { + if (cpufreq_driver->get && !cpufreq_driver->setpolicy) { new_policy.cur = cpufreq_driver->get(cpu); if (!policy->cur) { pr_debug("Driver did not initialize current freq"); @@ -2106,6 +2205,73 @@ 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 * *********************************************************************/ @@ -2145,9 +2311,25 @@ 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; @@ -2174,6 +2356,9 @@ 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; @@ -2200,6 +2385,9 @@ 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); |