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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Generic OPP helper interface for CPU device4 *5 * Copyright (C) 2009-2014 Texas Instruments Incorporated.6 * Nishanth Menon7 * Romit Dasgupta8 * Kevin Hilman9 */10 11#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt12 13#include <linux/cpu.h>14#include <linux/cpufreq.h>15#include <linux/err.h>16#include <linux/errno.h>17#include <linux/export.h>18#include <linux/slab.h>19 20#include "opp.h"21 22#ifdef CONFIG_CPU_FREQ23 24/**25 * dev_pm_opp_init_cpufreq_table() - create a cpufreq table for a device26 * @dev: device for which we do this operation27 * @opp_table: Cpufreq table returned back to caller28 *29 * Generate a cpufreq table for a provided device- this assumes that the30 * opp table is already initialized and ready for usage.31 *32 * This function allocates required memory for the cpufreq table. It is33 * expected that the caller does the required maintenance such as freeing34 * the table as required.35 *36 * Returns -EINVAL for bad pointers, -ENODEV if the device is not found, -ENOMEM37 * if no memory available for the operation (table is not populated), returns 038 * if successful and table is populated.39 *40 * WARNING: It is important for the callers to ensure refreshing their copy of41 * the table if any of the mentioned functions have been invoked in the interim.42 */43int dev_pm_opp_init_cpufreq_table(struct device *dev,44 struct cpufreq_frequency_table **opp_table)45{46 struct dev_pm_opp *opp;47 struct cpufreq_frequency_table *freq_table = NULL;48 int i, max_opps, ret = 0;49 unsigned long rate;50 51 max_opps = dev_pm_opp_get_opp_count(dev);52 if (max_opps <= 0)53 return max_opps ? max_opps : -ENODATA;54 55 freq_table = kcalloc((max_opps + 1), sizeof(*freq_table), GFP_KERNEL);56 if (!freq_table)57 return -ENOMEM;58 59 for (i = 0, rate = 0; i < max_opps; i++, rate++) {60 /* find next rate */61 opp = dev_pm_opp_find_freq_ceil(dev, &rate);62 if (IS_ERR(opp)) {63 ret = PTR_ERR(opp);64 goto out;65 }66 freq_table[i].driver_data = i;67 freq_table[i].frequency = rate / 1000;68 69 /* Is Boost/turbo opp ? */70 if (dev_pm_opp_is_turbo(opp))71 freq_table[i].flags = CPUFREQ_BOOST_FREQ;72 73 dev_pm_opp_put(opp);74 }75 76 freq_table[i].driver_data = i;77 freq_table[i].frequency = CPUFREQ_TABLE_END;78 79 *opp_table = &freq_table[0];80 81out:82 if (ret)83 kfree(freq_table);84 85 return ret;86}87EXPORT_SYMBOL_GPL(dev_pm_opp_init_cpufreq_table);88 89/**90 * dev_pm_opp_free_cpufreq_table() - free the cpufreq table91 * @dev: device for which we do this operation92 * @opp_table: table to free93 *94 * Free up the table allocated by dev_pm_opp_init_cpufreq_table95 */96void dev_pm_opp_free_cpufreq_table(struct device *dev,97 struct cpufreq_frequency_table **opp_table)98{99 if (!opp_table)100 return;101 102 kfree(*opp_table);103 *opp_table = NULL;104}105EXPORT_SYMBOL_GPL(dev_pm_opp_free_cpufreq_table);106#endif /* CONFIG_CPU_FREQ */107 108void _dev_pm_opp_cpumask_remove_table(const struct cpumask *cpumask,109 int last_cpu)110{111 struct device *cpu_dev;112 int cpu;113 114 WARN_ON(cpumask_empty(cpumask));115 116 for_each_cpu(cpu, cpumask) {117 if (cpu == last_cpu)118 break;119 120 cpu_dev = get_cpu_device(cpu);121 if (!cpu_dev) {122 pr_err("%s: failed to get cpu%d device\n", __func__,123 cpu);124 continue;125 }126 127 dev_pm_opp_remove_table(cpu_dev);128 }129}130 131/**132 * dev_pm_opp_cpumask_remove_table() - Removes OPP table for @cpumask133 * @cpumask: cpumask for which OPP table needs to be removed134 *135 * This removes the OPP tables for CPUs present in the @cpumask.136 * This should be used to remove all the OPPs entries associated with137 * the cpus in @cpumask.138 */139void dev_pm_opp_cpumask_remove_table(const struct cpumask *cpumask)140{141 _dev_pm_opp_cpumask_remove_table(cpumask, -1);142}143EXPORT_SYMBOL_GPL(dev_pm_opp_cpumask_remove_table);144 145/**146 * dev_pm_opp_set_sharing_cpus() - Mark OPP table as shared by few CPUs147 * @cpu_dev: CPU device for which we do this operation148 * @cpumask: cpumask of the CPUs which share the OPP table with @cpu_dev149 *150 * This marks OPP table of the @cpu_dev as shared by the CPUs present in151 * @cpumask.152 *153 * Returns -ENODEV if OPP table isn't already present.154 */155int dev_pm_opp_set_sharing_cpus(struct device *cpu_dev,156 const struct cpumask *cpumask)157{158 struct opp_device *opp_dev;159 struct opp_table *opp_table;160 struct device *dev;161 int cpu, ret = 0;162 163 opp_table = _find_opp_table(cpu_dev);164 if (IS_ERR(opp_table))165 return PTR_ERR(opp_table);166 167 for_each_cpu(cpu, cpumask) {168 if (cpu == cpu_dev->id)169 continue;170 171 dev = get_cpu_device(cpu);172 if (!dev) {173 dev_err(cpu_dev, "%s: failed to get cpu%d device\n",174 __func__, cpu);175 continue;176 }177 178 opp_dev = _add_opp_dev(dev, opp_table);179 if (!opp_dev) {180 dev_err(dev, "%s: failed to add opp-dev for cpu%d device\n",181 __func__, cpu);182 continue;183 }184 185 /* Mark opp-table as multiple CPUs are sharing it now */186 opp_table->shared_opp = OPP_TABLE_ACCESS_SHARED;187 }188 189 dev_pm_opp_put_opp_table(opp_table);190 191 return ret;192}193EXPORT_SYMBOL_GPL(dev_pm_opp_set_sharing_cpus);194 195/**196 * dev_pm_opp_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with @cpu_dev197 * @cpu_dev: CPU device for which we do this operation198 * @cpumask: cpumask to update with information of sharing CPUs199 *200 * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev.201 *202 * Returns -ENODEV if OPP table isn't already present and -EINVAL if the OPP203 * table's status is access-unknown.204 */205int dev_pm_opp_get_sharing_cpus(struct device *cpu_dev, struct cpumask *cpumask)206{207 struct opp_device *opp_dev;208 struct opp_table *opp_table;209 int ret = 0;210 211 opp_table = _find_opp_table(cpu_dev);212 if (IS_ERR(opp_table))213 return PTR_ERR(opp_table);214 215 if (opp_table->shared_opp == OPP_TABLE_ACCESS_UNKNOWN) {216 ret = -EINVAL;217 goto put_opp_table;218 }219 220 cpumask_clear(cpumask);221 222 if (opp_table->shared_opp == OPP_TABLE_ACCESS_SHARED) {223 mutex_lock(&opp_table->lock);224 list_for_each_entry(opp_dev, &opp_table->dev_list, node)225 cpumask_set_cpu(opp_dev->dev->id, cpumask);226 mutex_unlock(&opp_table->lock);227 } else {228 cpumask_set_cpu(cpu_dev->id, cpumask);229 }230 231put_opp_table:232 dev_pm_opp_put_opp_table(opp_table);233 234 return ret;235}236EXPORT_SYMBOL_GPL(dev_pm_opp_get_sharing_cpus);237