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 | * @opp_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 **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(n: (max_opps + 1), size: 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, freq: &rate); |
62 | if (IS_ERR(ptr: opp)) { |
63 | ret = PTR_ERR(ptr: 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 | |
81 | out: |
82 | if (ret) |
83 | kfree(objp: 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 | * @opp_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 **opp_table) |
98 | { |
99 | if (!opp_table) |
100 | return; |
101 | |
102 | kfree(objp: *opp_table); |
103 | *opp_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(dev: 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, last_cpu: -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(dev: cpu_dev); |
164 | if (IS_ERR(ptr: opp_table)) |
165 | return PTR_ERR(ptr: 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(dev: cpu_dev); |
212 | if (IS_ERR(ptr: opp_table)) |
213 | return PTR_ERR(ptr: 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(dstp: 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(cpu: opp_dev->dev->id, dstp: cpumask); |
226 | mutex_unlock(lock: &opp_table->lock); |
227 | } else { |
228 | cpumask_set_cpu(cpu: cpu_dev->id, dstp: 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 | |