/* * 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 <linux/cpu.h> #include <linux/cpufreq.h> #include <linux/err.h> #include <linux/errno.h> #include <linux/export.h> #include <linux/slab.h> #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 table 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. */ 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; max_opps = dev_pm_opp_get_opp_count(dev); if (max_opps <= 0) return max_opps ? max_opps : -ENODATA; freq_table = kcalloc((max_opps + 1), sizeof(*freq_table), GFP_KERNEL); if (!freq_table) return -ENOMEM; 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; dev_pm_opp_put(opp); } freq_table[i].driver_data = i; freq_table[i].frequency = CPUFREQ_TABLE_END; *table = &freq_table[0]; out: 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 */ void _dev_pm_opp_cpumask_remove_table(const struct cpumask *cpumask, int last_cpu) { struct device *cpu_dev; int cpu; WARN_ON(cpumask_empty(cpumask)); for_each_cpu(cpu, cpumask) { if (cpu == last_cpu) break; 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_find_and_remove_table(cpu_dev); } } /** * dev_pm_opp_cpumask_remove_table() - Removes OPP table for @cpumask * @cpumask: cpumask for which OPP table needs to be removed * * This removes the OPP tables for CPUs present in the @cpumask. * This should be used to remove all the OPPs entries associated with * the cpus in @cpumask. */ void dev_pm_opp_cpumask_remove_table(const struct cpumask *cpumask) { _dev_pm_opp_cpumask_remove_table(cpumask, -1); } EXPORT_SYMBOL_GPL(dev_pm_opp_cpumask_remove_table); /** * dev_pm_opp_set_sharing_cpus() - Mark OPP table as shared by few CPUs * @cpu_dev: CPU device for which we do this operation * @cpumask: cpumask of the CPUs which share the OPP table with @cpu_dev * * This marks OPP table of the @cpu_dev as shared by the CPUs present in * @cpumask. * * Returns -ENODEV if OPP table isn't already present. */ int dev_pm_opp_set_sharing_cpus(struct device *cpu_dev, const struct cpumask *cpumask) { struct opp_device *opp_dev; struct opp_table *opp_table; struct device *dev; int cpu, ret = 0; opp_table = _find_opp_table(cpu_dev); if (IS_ERR(opp_table)) return PTR_ERR(opp_table); 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; } opp_dev = _add_opp_dev(dev, opp_table); if (!opp_dev) { dev_err(dev, "%s: failed to add opp-dev for cpu%d device\n", __func__, cpu); continue; } /* Mark opp-table as multiple CPUs are sharing it now */ opp_table->shared_opp = OPP_TABLE_ACCESS_SHARED; } dev_pm_opp_put_opp_table(opp_table); return ret; } EXPORT_SYMBOL_GPL(dev_pm_opp_set_sharing_cpus); /** * dev_pm_opp_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with @cpu_dev * @cpu_dev: CPU device for which we do this operation * @cpumask: cpumask to update with information of sharing CPUs * * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev. * * Returns -ENODEV if OPP table isn't already present and -EINVAL if the OPP * table's status is access-unknown. */ int dev_pm_opp_get_sharing_cpus(struct device *cpu_dev, struct cpumask *cpumask) { struct opp_device *opp_dev; struct opp_table *opp_table; int ret = 0; opp_table = _find_opp_table(cpu_dev); if (IS_ERR(opp_table)) return PTR_ERR(opp_table); if (opp_table->shared_opp == OPP_TABLE_ACCESS_UNKNOWN) { ret = -EINVAL; goto put_opp_table; } cpumask_clear(cpumask); if (opp_table->shared_opp == OPP_TABLE_ACCESS_SHARED) { mutex_lock(&opp_table->lock); list_for_each_entry(opp_dev, &opp_table->dev_list, node) cpumask_set_cpu(opp_dev->dev->id, cpumask); mutex_unlock(&opp_table->lock); } else { cpumask_set_cpu(cpu_dev->id, cpumask); } put_opp_table: dev_pm_opp_put_opp_table(opp_table); return ret; } EXPORT_SYMBOL_GPL(dev_pm_opp_get_sharing_cpus);