1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Generic OPP helper interface for CPU device 4 * 5 * Copyright (C) 2009-2014 Texas Instruments Incorporated. 6 * Nishanth Menon 7 * Romit Dasgupta 8 * Kevin Hilman 9 */ 10 11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 12 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_FREQ 23 24 /** 25 * dev_pm_opp_init_cpufreq_table() - create a cpufreq table for a device 26 * @dev: device for which we do this operation 27 * @table: Cpufreq table returned back to caller 28 * 29 * Generate a cpufreq table for a provided device- this assumes that the 30 * opp table is already initialized and ready for usage. 31 * 32 * This function allocates required memory for the cpufreq table. It is 33 * expected that the caller does the required maintenance such as freeing 34 * the table as required. 35 * 36 * Returns -EINVAL for bad pointers, -ENODEV if the device is not found, -ENOMEM 37 * if no memory available for the operation (table is not populated), returns 0 38 * if successful and table is populated. 39 * 40 * WARNING: It is important for the callers to ensure refreshing their copy of 41 * the table if any of the mentioned functions have been invoked in the interim. 42 */ 43 int dev_pm_opp_init_cpufreq_table(struct device *dev, 44 struct cpufreq_frequency_table **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 *table = &freq_table[0]; 80 81 out: 82 if (ret) 83 kfree(freq_table); 84 85 return ret; 86 } 87 EXPORT_SYMBOL_GPL(dev_pm_opp_init_cpufreq_table); 88 89 /** 90 * dev_pm_opp_free_cpufreq_table() - free the cpufreq table 91 * @dev: device for which we do this operation 92 * @table: table to free 93 * 94 * Free up the table allocated by dev_pm_opp_init_cpufreq_table 95 */ 96 void dev_pm_opp_free_cpufreq_table(struct device *dev, 97 struct cpufreq_frequency_table **table) 98 { 99 if (!table) 100 return; 101 102 kfree(*table); 103 *table = NULL; 104 } 105 EXPORT_SYMBOL_GPL(dev_pm_opp_free_cpufreq_table); 106 #endif /* CONFIG_CPU_FREQ */ 107 108 void _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 @cpumask 133 * @cpumask: cpumask for which OPP table needs to be removed 134 * 135 * This removes the OPP tables for CPUs present in the @cpumask. 136 * This should be used to remove all the OPPs entries associated with 137 * the cpus in @cpumask. 138 */ 139 void dev_pm_opp_cpumask_remove_table(const struct cpumask *cpumask) 140 { 141 _dev_pm_opp_cpumask_remove_table(cpumask, -1); 142 } 143 EXPORT_SYMBOL_GPL(dev_pm_opp_cpumask_remove_table); 144 145 /** 146 * dev_pm_opp_set_sharing_cpus() - Mark OPP table as shared by few CPUs 147 * @cpu_dev: CPU device for which we do this operation 148 * @cpumask: cpumask of the CPUs which share the OPP table with @cpu_dev 149 * 150 * This marks OPP table of the @cpu_dev as shared by the CPUs present in 151 * @cpumask. 152 * 153 * Returns -ENODEV if OPP table isn't already present. 154 */ 155 int 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 } 193 EXPORT_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_dev 197 * @cpu_dev: CPU device for which we do this operation 198 * @cpumask: cpumask to update with information of sharing CPUs 199 * 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 OPP 203 * table's status is access-unknown. 204 */ 205 int 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 } 230 231 put_opp_table: 232 dev_pm_opp_put_opp_table(opp_table); 233 234 return ret; 235 } 236 EXPORT_SYMBOL_GPL(dev_pm_opp_get_sharing_cpus); 237