/* * Generic OPP helper interface for CPU device * * Copyright (C) 2009-2014 Texas Instruments Incorporated. * Nishanth Menon * Romit Dasgupta * Kevin Hilman * * 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 #include #include #include #include #include #include #include "opp.h" #ifdef CONFIG_CPU_FREQ /** * dev_pm_opp_init_cpufreq_table() - create a cpufreq table for a device * @dev: device for which we do this operation * @table: Cpufreq table returned back to caller * * Generate a cpufreq table for a provided device- this assumes that the * opp list is already initialized and ready for usage. * * This function allocates required memory for the cpufreq table. It is * expected that the caller does the required maintenance such as freeing * the table as required. * * Returns -EINVAL for bad pointers, -ENODEV if the device is not found, -ENOMEM * if no memory available for the operation (table is not populated), returns 0 * if successful and table is populated. * * WARNING: It is important for the callers to ensure refreshing their copy of * the table if any of the mentioned functions have been invoked in the interim. * * Locking: The internal device_opp and opp structures are RCU protected. * Since we just use the regular accessor functions to access the internal data * structures, we use RCU read lock inside this function. As a result, users of * this function DONOT need to use explicit locks for invoking. */ int dev_pm_opp_init_cpufreq_table(struct device *dev, struct cpufreq_frequency_table **table) { struct dev_pm_opp *opp; struct cpufreq_frequency_table *freq_table = NULL; int i, max_opps, ret = 0; unsigned long rate; rcu_read_lock(); max_opps = dev_pm_opp_get_opp_count(dev); if (max_opps <= 0) { ret = max_opps ? max_opps : -ENODATA; goto out; } freq_table = kcalloc((max_opps + 1), sizeof(*freq_table), GFP_ATOMIC); if (!freq_table) { ret = -ENOMEM; goto out; } for (i = 0, rate = 0; i < max_opps; i++, rate++) { /* find next rate */ opp = dev_pm_opp_find_freq_ceil(dev, &rate); if (IS_ERR(opp)) { ret = PTR_ERR(opp); goto out; } freq_table[i].driver_data = i; freq_table[i].frequency = rate / 1000; /* Is Boost/turbo opp ? */ if (dev_pm_opp_is_turbo(opp)) freq_table[i].flags = CPUFREQ_BOOST_FREQ; } freq_table[i].driver_data = i; freq_table[i].frequency = CPUFREQ_TABLE_END; *table = &freq_table[0]; out: rcu_read_unlock(); if (ret) kfree(freq_table); return ret; } EXPORT_SYMBOL_GPL(dev_pm_opp_init_cpufreq_table); /** * dev_pm_opp_free_cpufreq_table() - free the cpufreq table * @dev: device for which we do this operation * @table: table to free * * Free up the table allocated by dev_pm_opp_init_cpufreq_table */ void dev_pm_opp_free_cpufreq_table(struct device *dev, struct cpufreq_frequency_table **table) { if (!table) return; kfree(*table); *table = NULL; } EXPORT_SYMBOL_GPL(dev_pm_opp_free_cpufreq_table); #endif /* CONFIG_CPU_FREQ */ /* Required only for V1 bindings, as v2 can manage it from DT itself */ int dev_pm_opp_set_sharing_cpus(struct device *cpu_dev, cpumask_var_t cpumask) { struct device_list_opp *list_dev; struct device_opp *dev_opp; struct device *dev; int cpu, ret = 0; mutex_lock(&dev_opp_list_lock); dev_opp = _find_device_opp(cpu_dev); if (IS_ERR(dev_opp)) { ret = -EINVAL; goto unlock; } for_each_cpu(cpu, cpumask) { if (cpu == cpu_dev->id) continue; dev = get_cpu_device(cpu); if (!dev) { dev_err(cpu_dev, "%s: failed to get cpu%d device\n", __func__, cpu); continue; } list_dev = _add_list_dev(dev, dev_opp); if (!list_dev) { dev_err(dev, "%s: failed to add list-dev for cpu%d device\n", __func__, cpu); continue; } } unlock: mutex_unlock(&dev_opp_list_lock); return ret; } EXPORT_SYMBOL_GPL(dev_pm_opp_set_sharing_cpus); #ifdef CONFIG_OF void dev_pm_opp_of_cpumask_remove_table(cpumask_var_t cpumask) { struct device *cpu_dev; int cpu; WARN_ON(cpumask_empty(cpumask)); for_each_cpu(cpu, cpumask) { cpu_dev = get_cpu_device(cpu); if (!cpu_dev) { pr_err("%s: failed to get cpu%d device\n", __func__, cpu); continue; } dev_pm_opp_of_remove_table(cpu_dev); } } EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_remove_table); int dev_pm_opp_of_cpumask_add_table(cpumask_var_t cpumask) { struct device *cpu_dev; int cpu, ret = 0; WARN_ON(cpumask_empty(cpumask)); for_each_cpu(cpu, cpumask) { cpu_dev = get_cpu_device(cpu); if (!cpu_dev) { pr_err("%s: failed to get cpu%d device\n", __func__, cpu); continue; } ret = dev_pm_opp_of_add_table(cpu_dev); if (ret) { pr_err("%s: couldn't find opp table for cpu:%d, %d\n", __func__, cpu, ret); /* Free all other OPPs */ dev_pm_opp_of_cpumask_remove_table(cpumask); break; } } return ret; } EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_add_table); /* * Works only for OPP v2 bindings. * * cpumask should be already set to mask of cpu_dev->id. * Returns -ENOENT if operating-points-v2 bindings aren't supported. */ int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev, cpumask_var_t cpumask) { struct device_node *np, *tmp_np; struct device *tcpu_dev; int cpu, ret = 0; /* Get OPP descriptor node */ np = _of_get_opp_desc_node(cpu_dev); if (!np) { dev_dbg(cpu_dev, "%s: Couldn't find cpu_dev node.\n", __func__); return -ENOENT; } /* OPPs are shared ? */ if (!of_property_read_bool(np, "opp-shared")) goto put_cpu_node; for_each_possible_cpu(cpu) { if (cpu == cpu_dev->id) continue; tcpu_dev = get_cpu_device(cpu); if (!tcpu_dev) { dev_err(cpu_dev, "%s: failed to get cpu%d device\n", __func__, cpu); ret = -ENODEV; goto put_cpu_node; } /* Get OPP descriptor node */ tmp_np = _of_get_opp_desc_node(tcpu_dev); if (!tmp_np) { dev_err(tcpu_dev, "%s: Couldn't find tcpu_dev node.\n", __func__); ret = -ENOENT; goto put_cpu_node; } /* CPUs are sharing opp node */ if (np == tmp_np) cpumask_set_cpu(cpu, cpumask); of_node_put(tmp_np); } put_cpu_node: of_node_put(np); return ret; } EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus); #endif