/* * linux/drivers/thermal/gpu_cooling.c * * Copyright (C) 2012 Samsung Electronics Co., Ltd(http://www.samsung.com) * Copyright (C) 2012 Amit Daniel * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * 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 "exynos_tmu_data.h" /** * struct gpufreq_cooling_device - data for cooling device with gpufreq * @id: unique integer value corresponding to each gpufreq_cooling_device * registered. * @cool_dev: thermal_cooling_device pointer to keep track of the * registered cooling device. * @gpufreq_state: integer value representing the current state of gpufreq * cooling devices. * @gpufreq_val: integer value representing the absolute value of the clipped * frequency. * @allowed_gpus: all the gpus involved for this gpufreq_cooling_device. * * This structure is required for keeping information of each * gpufreq_cooling_device registered. In order to prevent corruption of this a * mutex lock cooling_gpu_lock is used. */ struct gpufreq_cooling_device { int id; struct thermal_cooling_device *cool_dev; unsigned int gpufreq_state; unsigned int gpufreq_val; }; static DEFINE_IDR(gpufreq_idr); static DEFINE_MUTEX(cooling_gpu_lock); static BLOCKING_NOTIFIER_HEAD(gpu_notifier); static unsigned int gpufreq_dev_count; extern struct cpufreq_frequency_table gpu_freq_table[]; /** * 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_gpu_lock); ret = idr_alloc(idr, NULL, 0, 0, GFP_KERNEL); mutex_unlock(&cooling_gpu_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_gpu_lock); idr_remove(idr, id); mutex_unlock(&cooling_gpu_lock); } /* Below code defines functions to be used for gpufreq as cooling device */ enum gpufreq_cooling_property { GET_LEVEL, GET_FREQ, GET_MAXL, }; /** * get_property - fetch a property of interest for a give gpu. * @gpu: gpu for which the property is required * @input: query parameter * @output: query return * @property: type of query (frequency, level, max level) * * This is the common function to * 1. get maximum gpu cooling states * 2. translate frequency to cooling state * 3. translate cooling state to frequency * Note that the code may be not in good shape * but it is written in this way in order to: * a) reduce duplicate code as most of the code can be shared. * b) make sure the logic is consistent when translating between * cooling states and frequencies. * * Return: 0 on success, -EINVAL when invalid parameters are passed. */ static int get_property(unsigned int gpu, unsigned long input, unsigned int *output, enum gpufreq_cooling_property property) { int i; unsigned long max_level = 0, level = 0; unsigned int freq = CPUFREQ_ENTRY_INVALID; int descend = -1; struct cpufreq_frequency_table *pos, *table = gpu_freq_table; if (!output) return -EINVAL; cpufreq_for_each_valid_entry(pos, table) { /* ignore duplicate entry */ if (freq == pos->frequency) continue; /* get the frequency order */ if (freq != CPUFREQ_ENTRY_INVALID && descend == -1) descend = freq > pos->frequency; freq = pos->frequency; max_level++; } /* No valid cpu frequency entry */ if (max_level == 0) return -EINVAL; /* max_level is an index, not a counter */ max_level--; /* get max level */ if (property == GET_MAXL) { *output = (unsigned int)max_level; return 0; } if (property == GET_FREQ) level = descend ? input : (max_level - input); i = 0; cpufreq_for_each_valid_entry(pos, table) { /* ignore duplicate entry */ if (freq == pos->frequency) continue; /* now we have a valid frequency entry */ freq = pos->frequency; if (property == GET_LEVEL && (unsigned int)input == freq) { /* get level by frequency */ *output = descend ? i : (max_level - i); return 0; } if (property == GET_FREQ && level == i) { /* get frequency by level */ *output = freq; return 0; } i++; } return -EINVAL; } /** * gpufreq_cooling_get_level - for a give gpu, return the cooling level. * @gpu: gpu 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 gpufreq_cooling_get_level(unsigned int gpu, unsigned int freq) { unsigned int val; if (get_property(gpu, (unsigned long)freq, &val, GET_LEVEL)) return THERMAL_CSTATE_INVALID; return (unsigned long)val; } EXPORT_SYMBOL_GPL(gpufreq_cooling_get_level); /** * gpufreq_apply_cooling - function to apply frequency clipping. * @gpufreq_device: gpufreq_cooling_device pointer containing frequency * clipping data. * @cooling_state: value of the cooling state. * * Function used to make sure the gpufreq layer is aware of current thermal * limits. The limits are applied by updating the gpufreq policy. * * Return: 0 on success, an error code otherwise (-EINVAL in case wrong * cooling state). */ static int gpufreq_apply_cooling(struct gpufreq_cooling_device *gpufreq_device, unsigned long cooling_state) { /* Check if the old cooling action is same as new cooling action */ if (gpufreq_device->gpufreq_state == cooling_state) return 0; gpufreq_device->gpufreq_state = cooling_state; blocking_notifier_call_chain(&gpu_notifier, GPU_THROTTLING, &cooling_state); return 0; } /* gpufreq cooling device callback functions are defined below */ /** * gpufreq_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 gpufreq * max cooling state. * * Return: 0 on success, an error code otherwise. */ static int gpufreq_get_max_state(struct thermal_cooling_device *cdev, unsigned long *state) { unsigned int count = 0; int ret; ret = get_property(0, 0, &count, GET_MAXL); if (count > 0) *state = count; return ret; } /** * gpufreq_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 gpufreq * current cooling state. * * Return: 0 on success, an error code otherwise. */ static int gpufreq_get_cur_state(struct thermal_cooling_device *cdev, unsigned long *state) { struct gpufreq_cooling_device *gpufreq_device = cdev->devdata; *state = gpufreq_device->gpufreq_state; return 0; } /** * gpufreq_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 gpufreq * current cooling state. * * Return: 0 on success, an error code otherwise. */ static int gpufreq_set_cur_state(struct thermal_cooling_device *cdev, unsigned long state) { struct gpufreq_cooling_device *gpufreq_device = cdev->devdata; return gpufreq_apply_cooling(gpufreq_device, state); } static enum tmu_noti_state_t gpu_tstate = GPU_COLD; int gpufreq_set_cur_temp(bool suspended, unsigned long temp) { enum tmu_noti_state_t tstate; if (suspended || temp < EXYNOS_COLD_TEMP) tstate = GPU_COLD; else tstate = GPU_NORMAL; if (gpu_tstate == tstate) return 0; gpu_tstate = tstate; blocking_notifier_call_chain(&gpu_notifier, tstate, &tstate); return 0; } /* Bind gpufreq callbacks to thermal cooling device ops */ static struct thermal_cooling_device_ops const gpufreq_cooling_ops = { .get_max_state = gpufreq_get_max_state, .get_cur_state = gpufreq_get_cur_state, .set_cur_state = gpufreq_set_cur_state, }; int exynos_gpu_add_notifier(struct notifier_block *n) { return blocking_notifier_chain_register(&gpu_notifier, n); } /** * __gpufreq_cooling_register - helper function to create gpufreq cooling device * @np: a valid struct device_node to the cooling device device tree node * @clip_gpus: gpumask of gpus where the frequency constraints will happen. * * This interface function registers the gpufreq cooling device with the name * "thermal-gpufreq-%x". This api can support multiple instances of gpufreq * 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 * __gpufreq_cooling_register(struct device_node *np, const struct cpumask *clip_gpus) { struct thermal_cooling_device *cool_dev; struct gpufreq_cooling_device *gpufreq_dev = NULL; char dev_name[THERMAL_NAME_LENGTH]; int ret = 0; gpufreq_dev = kzalloc(sizeof(struct gpufreq_cooling_device), GFP_KERNEL); if (!gpufreq_dev) return ERR_PTR(-ENOMEM); ret = get_idr(&gpufreq_idr, &gpufreq_dev->id); if (ret) { kfree(gpufreq_dev); return ERR_PTR(-EINVAL); } snprintf(dev_name, sizeof(dev_name), "thermal-gpufreq-%d", gpufreq_dev->id); cool_dev = thermal_of_cooling_device_register(np, dev_name, gpufreq_dev, &gpufreq_cooling_ops); if (IS_ERR(cool_dev)) { release_idr(&gpufreq_idr, gpufreq_dev->id); kfree(gpufreq_dev); return cool_dev; } gpufreq_dev->cool_dev = cool_dev; gpufreq_dev->gpufreq_state = 0; mutex_lock(&cooling_gpu_lock); gpufreq_dev_count++; mutex_unlock(&cooling_gpu_lock); return cool_dev; } /** * gpufreq_cooling_register - function to create gpufreq cooling device. * @clip_gpus: cpumask of gpus where the frequency constraints will happen. * * This interface function registers the gpufreq cooling device with the name * "thermal-gpufreq-%x". This api can support multiple instances of gpufreq * cooling devices. * * Return: a valid struct thermal_cooling_device pointer on success, * on failure, it returns a corresponding ERR_PTR(). */ struct thermal_cooling_device * gpufreq_cooling_register(const struct cpumask *clip_gpus) { return __gpufreq_cooling_register(NULL, clip_gpus); } EXPORT_SYMBOL_GPL(gpufreq_cooling_register); /** * of_gpufreq_cooling_register - function to create gpufreq cooling device. * @np: a valid struct device_node to the cooling device device tree node * @clip_gpus: cpumask of gpus where the frequency constraints will happen. * * This interface function registers the gpufreq cooling device with the name * "thermal-gpufreq-%x". This api can support multiple instances of gpufreq * cooling devices. Using this API, the gpufreq 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_gpufreq_cooling_register(struct device_node *np, const struct cpumask *clip_gpus) { if (!np) return ERR_PTR(-EINVAL); return __gpufreq_cooling_register(np, clip_gpus); } EXPORT_SYMBOL_GPL(of_gpufreq_cooling_register); /** * gpufreq_cooling_unregister - function to remove gpufreq cooling device. * @cdev: thermal cooling device pointer. * * This interface function unregisters the "thermal-gpufreq-%x" cooling device. */ void gpufreq_cooling_unregister(struct thermal_cooling_device *cdev) { struct gpufreq_cooling_device *gpufreq_dev; if (!cdev) return; gpufreq_dev = cdev->devdata; mutex_lock(&cooling_gpu_lock); gpufreq_dev_count--; mutex_unlock(&cooling_gpu_lock); thermal_cooling_device_unregister(gpufreq_dev->cool_dev); release_idr(&gpufreq_idr, gpufreq_dev->id); kfree(gpufreq_dev); } EXPORT_SYMBOL_GPL(gpufreq_cooling_unregister);