/* * linux/drivers/thermal/cpu_cooling.c * * Copyright (C) 2012 Samsung Electronics Co., Ltd(http://www.samsung.com) * Copyright (C) 2012 Amit Daniel * * Copyright (C) 2014 Viresh Kumar * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; version 2 of the License. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA. * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ #include #include #include #include #include #include #include #include #include /* * Cooling state <-> CPUFreq frequency * * Cooling states are translated to frequencies throughout this driver and this * is the relation between them. * * Highest cooling state corresponds to lowest possible frequency. * * i.e. * level 0 --> 1st Max Freq * level 1 --> 2nd Max Freq * ... */ /** * struct power_table - frequency to power conversion * @frequency: frequency in KHz * @power: power in mW * * This structure is built when the cooling device registers and helps * in translating frequency to power and viceversa. */ struct power_table { u32 frequency; u32 power; }; /** * struct cpufreq_cooling_device - data for cooling device with cpufreq * @id: unique integer value corresponding to each cpufreq_cooling_device * registered. * @cool_dev: thermal_cooling_device pointer to keep track of the * registered cooling device. * @cpufreq_state: integer value representing the current state of cpufreq * cooling devices. * @cpufreq_val: integer value representing the absolute value of the clipped * frequency. * @max_level: maximum cooling level. One less than total number of valid * cpufreq frequencies. * @allowed_cpus: all the cpus involved for this cpufreq_cooling_device. * @node: list_head to link all cpufreq_cooling_device together. * @last_load: load measured by the latest call to cpufreq_get_actual_power() * @time_in_idle: previous reading of the absolute time that this cpu was idle * @time_in_idle_timestamp: wall time of the last invocation of * get_cpu_idle_time_us() * @dyn_power_table: array of struct power_table for frequency to power * conversion, sorted in ascending order. * @dyn_power_table_entries: number of entries in the @dyn_power_table array * @cpu_dev: the first cpu_device from @allowed_cpus that has OPPs registered * @plat_get_static_power: callback to calculate the static power * * This structure is required for keeping information of each registered * cpufreq_cooling_device. */ struct cpufreq_cooling_device { int id; struct thermal_cooling_device *cool_dev; unsigned int cpufreq_state; unsigned int cpufreq_val; unsigned int max_level; unsigned int *freq_table; /* In descending order */ struct cpumask allowed_cpus; struct list_head node; u32 last_load; u64 *time_in_idle; u64 *time_in_idle_timestamp; struct power_table *dyn_power_table; int dyn_power_table_entries; struct device *cpu_dev; get_static_t plat_get_static_power; }; static DEFINE_IDR(cpufreq_idr); static DEFINE_MUTEX(cooling_cpufreq_lock); static LIST_HEAD(cpufreq_dev_list); /** * get_idr - function to get a unique id. * @idr: struct idr * handle used to create a id. * @id: int * value generated by this function. * * This function will populate @id with an unique * id, using the idr API. * * Return: 0 on success, an error code on failure. */ static int get_idr(struct idr *idr, int *id) { int ret; mutex_lock(&cooling_cpufreq_lock); ret = idr_alloc(idr, NULL, 0, 0, GFP_KERNEL); mutex_unlock(&cooling_cpufreq_lock); if (unlikely(ret < 0)) return ret; *id = ret; return 0; } /** * release_idr - function to free the unique id. * @idr: struct idr * handle used for creating the id. * @id: int value representing the unique id. */ static void release_idr(struct idr *idr, int id) { mutex_lock(&cooling_cpufreq_lock); idr_remove(idr, id); mutex_unlock(&cooling_cpufreq_lock); } /* Below code defines functions to be used for cpufreq as cooling device */ /** * get_level: Find the level for a particular frequency * @cpufreq_dev: cpufreq_dev for which the property is required * @freq: Frequency * * Return: level on success, THERMAL_CSTATE_INVALID on error. */ static unsigned long get_level(struct cpufreq_cooling_device *cpufreq_dev, unsigned int freq) { unsigned long level; for (level = 0; level <= cpufreq_dev->max_level; level++) { if (freq == cpufreq_dev->freq_table[level]) return level; if (freq > cpufreq_dev->freq_table[level]) break; } return THERMAL_CSTATE_INVALID; } /** * cpufreq_cooling_get_level - for a given cpu, return the cooling level. * @cpu: cpu for which the level is required * @freq: the frequency of interest * * This function will match the cooling level corresponding to the * requested @freq and return it. * * Return: The matched cooling level on success or THERMAL_CSTATE_INVALID * otherwise. */ unsigned long cpufreq_cooling_get_level(unsigned int cpu, unsigned int freq) { struct cpufreq_cooling_device *cpufreq_dev; mutex_lock(&cooling_cpufreq_lock); list_for_each_entry(cpufreq_dev, &cpufreq_dev_list, node) { if (cpumask_test_cpu(cpu, &cpufreq_dev->allowed_cpus)) { mutex_unlock(&cooling_cpufreq_lock); return get_level(cpufreq_dev, freq); } } mutex_unlock(&cooling_cpufreq_lock); pr_err("%s: cpu:%d not part of any cooling device\n", __func__, cpu); return THERMAL_CSTATE_INVALID; } EXPORT_SYMBOL_GPL(cpufreq_cooling_get_level); /** * cpufreq_thermal_notifier - notifier callback for cpufreq policy change. * @nb: struct notifier_block * with callback info. * @event: value showing cpufreq event for which this function invoked. * @data: callback-specific data * * Callback to hijack the notification on cpufreq policy transition. * Every time there is a change in policy, we will intercept and * update the cpufreq policy with thermal constraints. * * Return: 0 (success) */ static int cpufreq_thermal_notifier(struct notifier_block *nb, unsigned long event, void *data) { struct cpufreq_policy *policy = data; unsigned long max_freq = 0; struct cpufreq_cooling_device *cpufreq_dev; switch (event) { case CPUFREQ_ADJUST: mutex_lock(&cooling_cpufreq_lock); list_for_each_entry(cpufreq_dev, &cpufreq_dev_list, node) { if (!cpumask_test_cpu(policy->cpu, &cpufreq_dev->allowed_cpus)) continue; max_freq = cpufreq_dev->cpufreq_val; if (policy->max != max_freq) cpufreq_verify_within_limits(policy, 0, max_freq); } mutex_unlock(&cooling_cpufreq_lock); break; default: return NOTIFY_DONE; } return NOTIFY_OK; } /** * build_dyn_power_table() - create a dynamic power to frequency table * @cpufreq_device: the cpufreq cooling device in which to store the table * @capacitance: dynamic power coefficient for these cpus * * Build a dynamic power to frequency table for this cpu and store it * in @cpufreq_device. This table will be used in cpu_power_to_freq() and * cpu_freq_to_power() to convert between power and frequency * efficiently. Power is stored in mW, frequency in KHz. The * resulting table is in ascending order. * * Return: 0 on success, -E* on error. */ static int build_dyn_power_table(struct cpufreq_cooling_device *cpufreq_device, u32 capacitance) { struct power_table *power_table; struct dev_pm_opp *opp; struct device *dev = NULL; int num_opps = 0, cpu, i, ret = 0; unsigned long freq; rcu_read_lock(); for_each_cpu(cpu, &cpufreq_device->allowed_cpus) { dev = get_cpu_device(cpu); if (!dev) { dev_warn(&cpufreq_device->cool_dev->device, "No cpu device for cpu %d\n", cpu); continue; } num_opps = dev_pm_opp_get_opp_count(dev); if (num_opps > 0) { break; } else if (num_opps < 0) { ret = num_opps; goto unlock; } } if (num_opps == 0) { ret = -EINVAL; goto unlock; } power_table = kcalloc(num_opps, sizeof(*power_table), GFP_KERNEL); for (freq = 0, i = 0; opp = dev_pm_opp_find_freq_ceil(dev, &freq), !IS_ERR(opp); freq++, i++) { u32 freq_mhz, voltage_mv; u64 power; freq_mhz = freq / 1000000; voltage_mv = dev_pm_opp_get_voltage(opp) / 1000; /* * Do the multiplication with MHz and millivolt so as * to not overflow. */ power = (u64)capacitance * freq_mhz * voltage_mv * voltage_mv; do_div(power, 1000000000); /* frequency is stored in power_table in KHz */ power_table[i].frequency = freq / 1000; /* power is stored in mW */ power_table[i].power = power; } if (i == 0) { ret = PTR_ERR(opp); goto unlock; } cpufreq_device->cpu_dev = dev; cpufreq_device->dyn_power_table = power_table; cpufreq_device->dyn_power_table_entries = i; unlock: rcu_read_unlock(); return ret; } static u32 cpu_freq_to_power(struct cpufreq_cooling_device *cpufreq_device, u32 freq) { int i; struct power_table *pt = cpufreq_device->dyn_power_table; for (i = 1; i < cpufreq_device->dyn_power_table_entries; i++) if (freq < pt[i].frequency) break; return pt[i - 1].power; } static u32 cpu_power_to_freq(struct cpufreq_cooling_device *cpufreq_device, u32 power) { int i; struct power_table *pt = cpufreq_device->dyn_power_table; for (i = 1; i < cpufreq_device->dyn_power_table_entries; i++) if (power < pt[i].power) break; return pt[i - 1].frequency; } /** * get_load() - get load for a cpu since last updated * @cpufreq_device: &struct cpufreq_cooling_device for this cpu * @cpu: cpu number * * Return: The average load of cpu @cpu in percentage since this * function was last called. */ static u32 get_load(struct cpufreq_cooling_device *cpufreq_device, int cpu) { u32 load; u64 now, now_idle, delta_time, delta_idle; now_idle = get_cpu_idle_time(cpu, &now, 0); delta_idle = now_idle - cpufreq_device->time_in_idle[cpu]; delta_time = now - cpufreq_device->time_in_idle_timestamp[cpu]; if (delta_time <= delta_idle) load = 0; else load = div64_u64(100 * (delta_time - delta_idle), delta_time); cpufreq_device->time_in_idle[cpu] = now_idle; cpufreq_device->time_in_idle_timestamp[cpu] = now; return load; } /** * get_static_power() - calculate the static power consumed by the cpus * @cpufreq_device: struct &cpufreq_cooling_device for this cpu cdev * @tz: thermal zone device in which we're operating * @freq: frequency in KHz * @power: pointer in which to store the calculated static power * * Calculate the static power consumed by the cpus described by * @cpu_actor running at frequency @freq. This function relies on a * platform specific function that should have been provided when the * actor was registered. If it wasn't, the static power is assumed to * be negligible. The calculated static power is stored in @power. * * Return: 0 on success, -E* on failure. */ static int get_static_power(struct cpufreq_cooling_device *cpufreq_device, struct thermal_zone_device *tz, unsigned long freq, u32 *power) { struct dev_pm_opp *opp; unsigned long voltage; struct cpumask *cpumask = &cpufreq_device->allowed_cpus; unsigned long freq_hz = freq * 1000; if (!cpufreq_device->plat_get_static_power || !cpufreq_device->cpu_dev) { *power = 0; return 0; } rcu_read_lock(); opp = dev_pm_opp_find_freq_exact(cpufreq_device->cpu_dev, freq_hz, true); voltage = dev_pm_opp_get_voltage(opp); rcu_read_unlock(); if (voltage == 0) { dev_warn_ratelimited(cpufreq_device->cpu_dev, "Failed to get voltage for frequency %lu: %ld\n", freq_hz, IS_ERR(opp) ? PTR_ERR(opp) : 0); return -EINVAL; } return cpufreq_device->plat_get_static_power(cpumask, tz->passive_delay, voltage, power); } /** * get_dynamic_power() - calculate the dynamic power * @cpufreq_device: &cpufreq_cooling_device for this cdev * @freq: current frequency * * Return: the dynamic power consumed by the cpus described by * @cpufreq_device. */ static u32 get_dynamic_power(struct cpufreq_cooling_device *cpufreq_device, unsigned long freq) { u32 raw_cpu_power; raw_cpu_power = cpu_freq_to_power(cpufreq_device, freq); return (raw_cpu_power * cpufreq_device->last_load) / 100; } /* cpufreq cooling device callback functions are defined below */ /** * cpufreq_get_max_state - callback function to get the max cooling state. * @cdev: thermal cooling device pointer. * @state: fill this variable with the max cooling state. * * Callback for the thermal cooling device to return the cpufreq * max cooling state. * * Return: 0 on success, an error code otherwise. */ static int cpufreq_get_max_state(struct thermal_cooling_device *cdev, unsigned long *state) { struct cpufreq_cooling_device *cpufreq_device = cdev->devdata; *state = cpufreq_device->max_level; return 0; } /** * cpufreq_get_cur_state - callback function to get the current cooling state. * @cdev: thermal cooling device pointer. * @state: fill this variable with the current cooling state. * * Callback for the thermal cooling device to return the cpufreq * current cooling state. * * Return: 0 on success, an error code otherwise. */ static int cpufreq_get_cur_state(struct thermal_cooling_device *cdev, unsigned long *state) { struct cpufreq_cooling_device *cpufreq_device = cdev->devdata; *state = cpufreq_device->cpufreq_state; return 0; } /** * cpufreq_set_cur_state - callback function to set the current cooling state. * @cdev: thermal cooling device pointer. * @state: set this variable to the current cooling state. * * Callback for the thermal cooling device to change the cpufreq * current cooling state. * * Return: 0 on success, an error code otherwise. */ static int cpufreq_set_cur_state(struct thermal_cooling_device *cdev, unsigned long state) { struct cpufreq_cooling_device *cpufreq_device = cdev->devdata; unsigned int cpu = cpumask_any(&cpufreq_device->allowed_cpus); unsigned int clip_freq; /* Request state should be less than max_level */ if (WARN_ON(state > cpufreq_device->max_level)) return -EINVAL; /* Check if the old cooling action is same as new cooling action */ if (cpufreq_device->cpufreq_state == state) return 0; clip_freq = cpufreq_device->freq_table[state]; cpufreq_device->cpufreq_state = state; cpufreq_device->cpufreq_val = clip_freq; cpufreq_update_policy(cpu); return 0; } /** * cpufreq_get_requested_power() - get the current power * @cdev: &thermal_cooling_device pointer * @tz: a valid thermal zone device pointer * @power: pointer in which to store the resulting power * * Calculate the current power consumption of the cpus in milliwatts * and store it in @power. This function should actually calculate * the requested power, but it's hard to get the frequency that * cpufreq would have assigned if there were no thermal limits. * Instead, we calculate the current power on the assumption that the * immediate future will look like the immediate past. * * We use the current frequency and the average load since this * function was last called. In reality, there could have been * multiple opps since this function was last called and that affects * the load calculation. While it's not perfectly accurate, this * simplification is good enough and works. REVISIT this, as more * complex code may be needed if experiments show that it's not * accurate enough. * * Return: 0 on success, -E* if getting the static power failed. */ static int cpufreq_get_requested_power(struct thermal_cooling_device *cdev, struct thermal_zone_device *tz, u32 *power) { unsigned long freq; int i = 0, cpu, ret; u32 static_power, dynamic_power, total_load = 0; struct cpufreq_cooling_device *cpufreq_device = cdev->devdata; u32 *load_cpu = NULL; cpu = cpumask_any_and(&cpufreq_device->allowed_cpus, cpu_online_mask); /* * All the CPUs are offline, thus the requested power by * the cdev is 0 */ if (cpu >= nr_cpu_ids) { *power = 0; return 0; } freq = cpufreq_quick_get(cpu); if (trace_thermal_power_cpu_get_power_enabled()) { u32 ncpus = cpumask_weight(&cpufreq_device->allowed_cpus); load_cpu = devm_kcalloc(&cdev->device, ncpus, sizeof(*load_cpu), GFP_KERNEL); } for_each_cpu(cpu, &cpufreq_device->allowed_cpus) { u32 load; if (cpu_online(cpu)) load = get_load(cpufreq_device, cpu); else load = 0; total_load += load; if (trace_thermal_power_cpu_limit_enabled() && load_cpu) load_cpu[i] = load; i++; } cpufreq_device->last_load = total_load; dynamic_power = get_dynamic_power(cpufreq_device, freq); ret = get_static_power(cpufreq_device, tz, freq, &static_power); if (ret) { if (load_cpu) devm_kfree(&cdev->device, load_cpu); return ret; } if (load_cpu) { trace_thermal_power_cpu_get_power( &cpufreq_device->allowed_cpus, freq, load_cpu, i, dynamic_power, static_power); devm_kfree(&cdev->device, load_cpu); } *power = static_power + dynamic_power; return 0; } /** * cpufreq_state2power() - convert a cpu cdev state to power consumed * @cdev: &thermal_cooling_device pointer * @tz: a valid thermal zone device pointer * @state: cooling device state to be converted * @power: pointer in which to store the resulting power * * Convert cooling device state @state into power consumption in * milliwatts assuming 100% load. Store the calculated power in * @power. * * Return: 0 on success, -EINVAL if the cooling device state could not * be converted into a frequency or other -E* if there was an error * when calculating the static power. */ static int cpufreq_state2power(struct thermal_cooling_device *cdev, struct thermal_zone_device *tz, unsigned long state, u32 *power) { unsigned int freq, num_cpus; cpumask_t cpumask; u32 static_power, dynamic_power; int ret; struct cpufreq_cooling_device *cpufreq_device = cdev->devdata; cpumask_and(&cpumask, &cpufreq_device->allowed_cpus, cpu_online_mask); num_cpus = cpumask_weight(&cpumask); /* None of our cpus are online, so no power */ if (num_cpus == 0) { *power = 0; return 0; } freq = cpufreq_device->freq_table[state]; if (!freq) return -EINVAL; dynamic_power = cpu_freq_to_power(cpufreq_device, freq) * num_cpus; ret = get_static_power(cpufreq_device, tz, freq, &static_power); if (ret) return ret; *power = static_power + dynamic_power; return 0; } /** * cpufreq_power2state() - convert power to a cooling device state * @cdev: &thermal_cooling_device pointer * @tz: a valid thermal zone device pointer * @power: power in milliwatts to be converted * @state: pointer in which to store the resulting state * * Calculate a cooling device state for the cpus described by @cdev * that would allow them to consume at most @power mW and store it in * @state. Note that this calculation depends on external factors * such as the cpu load or the current static power. Calling this * function with the same power as input can yield different cooling * device states depending on those external factors. * * Return: 0 on success, -ENODEV if no cpus are online or -EINVAL if * the calculated frequency could not be converted to a valid state. * The latter should not happen unless the frequencies available to * cpufreq have changed since the initialization of the cpu cooling * device. */ static int cpufreq_power2state(struct thermal_cooling_device *cdev, struct thermal_zone_device *tz, u32 power, unsigned long *state) { unsigned int cpu, cur_freq, target_freq; int ret; s32 dyn_power; u32 last_load, normalised_power, static_power; struct cpufreq_cooling_device *cpufreq_device = cdev->devdata; cpu = cpumask_any_and(&cpufreq_device->allowed_cpus, cpu_online_mask); /* None of our cpus are online */ if (cpu >= nr_cpu_ids) return -ENODEV; cur_freq = cpufreq_quick_get(cpu); ret = get_static_power(cpufreq_device, tz, cur_freq, &static_power); if (ret) return ret; dyn_power = power - static_power; dyn_power = dyn_power > 0 ? dyn_power : 0; last_load = cpufreq_device->last_load ?: 1; normalised_power = (dyn_power * 100) / last_load; target_freq = cpu_power_to_freq(cpufreq_device, normalised_power); *state = cpufreq_cooling_get_level(cpu, target_freq); if (*state == THERMAL_CSTATE_INVALID) { dev_warn_ratelimited(&cdev->device, "Failed to convert %dKHz for cpu %d into a cdev state\n", target_freq, cpu); return -EINVAL; } trace_thermal_power_cpu_limit(&cpufreq_device->allowed_cpus, target_freq, *state, power); return 0; } /* Bind cpufreq callbacks to thermal cooling device ops */ static struct thermal_cooling_device_ops cpufreq_cooling_ops = { .get_max_state = cpufreq_get_max_state, .get_cur_state = cpufreq_get_cur_state, .set_cur_state = cpufreq_set_cur_state, }; /* Notifier for cpufreq policy change */ static struct notifier_block thermal_cpufreq_notifier_block = { .notifier_call = cpufreq_thermal_notifier, }; static unsigned int find_next_max(struct cpufreq_frequency_table *table, unsigned int prev_max) { struct cpufreq_frequency_table *pos; unsigned int max = 0; cpufreq_for_each_valid_entry(pos, table) { if (pos->frequency > max && pos->frequency < prev_max) max = pos->frequency; } return max; } /** * __cpufreq_cooling_register - helper function to create cpufreq cooling device * @np: a valid struct device_node to the cooling device device tree node * @clip_cpus: cpumask of cpus where the frequency constraints will happen. * Normally this should be same as cpufreq policy->related_cpus. * @capacitance: dynamic power coefficient for these cpus * @plat_static_func: function to calculate the static power consumed by these * cpus (optional) * * This interface function registers the cpufreq cooling device with the name * "thermal-cpufreq-%x". This api can support multiple instances of cpufreq * cooling devices. It also gives the opportunity to link the cooling device * with a device tree node, in order to bind it via the thermal DT code. * * Return: a valid struct thermal_cooling_device pointer on success, * on failure, it returns a corresponding ERR_PTR(). */ static struct thermal_cooling_device * __cpufreq_cooling_register(struct device_node *np, const struct cpumask *clip_cpus, u32 capacitance, get_static_t plat_static_func) { struct thermal_cooling_device *cool_dev; struct cpufreq_cooling_device *cpufreq_dev; char dev_name[THERMAL_NAME_LENGTH]; struct cpufreq_frequency_table *pos, *table; unsigned int freq, i, num_cpus; int ret; table = cpufreq_frequency_get_table(cpumask_first(clip_cpus)); if (!table) { pr_debug("%s: CPUFreq table not found\n", __func__); return ERR_PTR(-EPROBE_DEFER); } cpufreq_dev = kzalloc(sizeof(*cpufreq_dev), GFP_KERNEL); if (!cpufreq_dev) return ERR_PTR(-ENOMEM); num_cpus = cpumask_weight(clip_cpus); cpufreq_dev->time_in_idle = kcalloc(num_cpus, sizeof(*cpufreq_dev->time_in_idle), GFP_KERNEL); if (!cpufreq_dev->time_in_idle) { cool_dev = ERR_PTR(-ENOMEM); goto free_cdev; } cpufreq_dev->time_in_idle_timestamp = kcalloc(num_cpus, sizeof(*cpufreq_dev->time_in_idle_timestamp), GFP_KERNEL); if (!cpufreq_dev->time_in_idle_timestamp) { cool_dev = ERR_PTR(-ENOMEM); goto free_time_in_idle; } /* Find max levels */ cpufreq_for_each_valid_entry(pos, table) cpufreq_dev->max_level++; cpufreq_dev->freq_table = kmalloc(sizeof(*cpufreq_dev->freq_table) * cpufreq_dev->max_level, GFP_KERNEL); if (!cpufreq_dev->freq_table) { cool_dev = ERR_PTR(-ENOMEM); goto free_time_in_idle_timestamp; } /* max_level is an index, not a counter */ cpufreq_dev->max_level--; cpumask_copy(&cpufreq_dev->allowed_cpus, clip_cpus); if (capacitance) { cpufreq_cooling_ops.get_requested_power = cpufreq_get_requested_power; cpufreq_cooling_ops.state2power = cpufreq_state2power; cpufreq_cooling_ops.power2state = cpufreq_power2state; cpufreq_dev->plat_get_static_power = plat_static_func; ret = build_dyn_power_table(cpufreq_dev, capacitance); if (ret) { cool_dev = ERR_PTR(ret); goto free_table; } } ret = get_idr(&cpufreq_idr, &cpufreq_dev->id); if (ret) { cool_dev = ERR_PTR(ret); goto free_table; } snprintf(dev_name, sizeof(dev_name), "thermal-cpufreq-%d", cpufreq_dev->id); cool_dev = thermal_of_cooling_device_register(np, dev_name, cpufreq_dev, &cpufreq_cooling_ops); if (IS_ERR(cool_dev)) goto remove_idr; /* Fill freq-table in descending order of frequencies */ for (i = 0, freq = -1; i <= cpufreq_dev->max_level; i++) { freq = find_next_max(table, freq); cpufreq_dev->freq_table[i] = freq; /* Warn for duplicate entries */ if (!freq) pr_warn("%s: table has duplicate entries\n", __func__); else pr_debug("%s: freq:%u KHz\n", __func__, freq); } cpufreq_dev->cpufreq_val = cpufreq_dev->freq_table[0]; cpufreq_dev->cool_dev = cool_dev; mutex_lock(&cooling_cpufreq_lock); /* Register the notifier for first cpufreq cooling device */ if (list_empty(&cpufreq_dev_list)) cpufreq_register_notifier(&thermal_cpufreq_notifier_block, CPUFREQ_POLICY_NOTIFIER); list_add(&cpufreq_dev->node, &cpufreq_dev_list); mutex_unlock(&cooling_cpufreq_lock); return cool_dev; remove_idr: release_idr(&cpufreq_idr, cpufreq_dev->id); free_table: kfree(cpufreq_dev->freq_table); free_time_in_idle_timestamp: kfree(cpufreq_dev->time_in_idle_timestamp); free_time_in_idle: kfree(cpufreq_dev->time_in_idle); free_cdev: kfree(cpufreq_dev); return cool_dev; } /** * cpufreq_cooling_register - function to create cpufreq cooling device. * @clip_cpus: cpumask of cpus where the frequency constraints will happen. * * This interface function registers the cpufreq cooling device with the name * "thermal-cpufreq-%x". This api can support multiple instances of cpufreq * cooling devices. * * Return: a valid struct thermal_cooling_device pointer on success, * on failure, it returns a corresponding ERR_PTR(). */ struct thermal_cooling_device * cpufreq_cooling_register(const struct cpumask *clip_cpus) { return __cpufreq_cooling_register(NULL, clip_cpus, 0, NULL); } EXPORT_SYMBOL_GPL(cpufreq_cooling_register); /** * of_cpufreq_cooling_register - function to create cpufreq cooling device. * @np: a valid struct device_node to the cooling device device tree node * @clip_cpus: cpumask of cpus where the frequency constraints will happen. * * This interface function registers the cpufreq cooling device with the name * "thermal-cpufreq-%x". This api can support multiple instances of cpufreq * cooling devices. Using this API, the cpufreq cooling device will be * linked to the device tree node provided. * * Return: a valid struct thermal_cooling_device pointer on success, * on failure, it returns a corresponding ERR_PTR(). */ struct thermal_cooling_device * of_cpufreq_cooling_register(struct device_node *np, const struct cpumask *clip_cpus) { if (!np) return ERR_PTR(-EINVAL); return __cpufreq_cooling_register(np, clip_cpus, 0, NULL); } EXPORT_SYMBOL_GPL(of_cpufreq_cooling_register); /** * cpufreq_power_cooling_register() - create cpufreq cooling device with power extensions * @clip_cpus: cpumask of cpus where the frequency constraints will happen * @capacitance: dynamic power coefficient for these cpus * @plat_static_func: function to calculate the static power consumed by these * cpus (optional) * * This interface function registers the cpufreq cooling device with * the name "thermal-cpufreq-%x". This api can support multiple * instances of cpufreq cooling devices. Using this function, the * cooling device will implement the power extensions by using a * simple cpu power model. The cpus must have registered their OPPs * using the OPP library. * * An optional @plat_static_func may be provided to calculate the * static power consumed by these cpus. If the platform's static * power consumption is unknown or negligible, make it NULL. * * Return: a valid struct thermal_cooling_device pointer on success, * on failure, it returns a corresponding ERR_PTR(). */ struct thermal_cooling_device * cpufreq_power_cooling_register(const struct cpumask *clip_cpus, u32 capacitance, get_static_t plat_static_func) { return __cpufreq_cooling_register(NULL, clip_cpus, capacitance, plat_static_func); } EXPORT_SYMBOL(cpufreq_power_cooling_register); /** * of_cpufreq_power_cooling_register() - create cpufreq cooling device with power extensions * @np: a valid struct device_node to the cooling device device tree node * @clip_cpus: cpumask of cpus where the frequency constraints will happen * @capacitance: dynamic power coefficient for these cpus * @plat_static_func: function to calculate the static power consumed by these * cpus (optional) * * This interface function registers the cpufreq cooling device with * the name "thermal-cpufreq-%x". This api can support multiple * instances of cpufreq cooling devices. Using this API, the cpufreq * cooling device will be linked to the device tree node provided. * Using this function, the cooling device will implement the power * extensions by using a simple cpu power model. The cpus must have * registered their OPPs using the OPP library. * * An optional @plat_static_func may be provided to calculate the * static power consumed by these cpus. If the platform's static * power consumption is unknown or negligible, make it NULL. * * Return: a valid struct thermal_cooling_device pointer on success, * on failure, it returns a corresponding ERR_PTR(). */ struct thermal_cooling_device * of_cpufreq_power_cooling_register(struct device_node *np, const struct cpumask *clip_cpus, u32 capacitance, get_static_t plat_static_func) { if (!np) return ERR_PTR(-EINVAL); return __cpufreq_cooling_register(np, clip_cpus, capacitance, plat_static_func); } EXPORT_SYMBOL(of_cpufreq_power_cooling_register); /** * cpufreq_cooling_unregister - function to remove cpufreq cooling device. * @cdev: thermal cooling device pointer. * * This interface function unregisters the "thermal-cpufreq-%x" cooling device. */ void cpufreq_cooling_unregister(struct thermal_cooling_device *cdev) { struct cpufreq_cooling_device *cpufreq_dev; if (!cdev) return; cpufreq_dev = cdev->devdata; mutex_lock(&cooling_cpufreq_lock); list_del(&cpufreq_dev->node); /* Unregister the notifier for the last cpufreq cooling device */ if (list_empty(&cpufreq_dev_list)) cpufreq_unregister_notifier(&thermal_cpufreq_notifier_block, CPUFREQ_POLICY_NOTIFIER); mutex_unlock(&cooling_cpufreq_lock); thermal_cooling_device_unregister(cpufreq_dev->cool_dev); release_idr(&cpufreq_idr, cpufreq_dev->id); kfree(cpufreq_dev->time_in_idle_timestamp); kfree(cpufreq_dev->time_in_idle); kfree(cpufreq_dev->freq_table); kfree(cpufreq_dev); } EXPORT_SYMBOL_GPL(cpufreq_cooling_unregister);