Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/j.anaszewski...
[linux-2.6-block.git] / drivers / cpufreq / cpufreq-dt.c
CommitLineData
95ceafd4
SG
1/*
2 * Copyright (C) 2012 Freescale Semiconductor, Inc.
3 *
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4 * Copyright (C) 2014 Linaro.
5 * Viresh Kumar <viresh.kumar@linaro.org>
6 *
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7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11
12#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
13
14#include <linux/clk.h>
e1825b25 15#include <linux/cpu.h>
77cff592 16#include <linux/cpu_cooling.h>
95ceafd4 17#include <linux/cpufreq.h>
34e5a527 18#include <linux/cpufreq-dt.h>
77cff592 19#include <linux/cpumask.h>
95ceafd4
SG
20#include <linux/err.h>
21#include <linux/module.h>
22#include <linux/of.h>
e4db1c74 23#include <linux/pm_opp.h>
5553f9e2 24#include <linux/platform_device.h>
95ceafd4
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25#include <linux/regulator/consumer.h>
26#include <linux/slab.h>
77cff592 27#include <linux/thermal.h>
95ceafd4 28
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29struct private_data {
30 struct device *cpu_dev;
d2f31f1d 31 struct thermal_cooling_device *cdev;
050794aa 32 const char *reg_name;
d2f31f1d 33};
95ceafd4 34
21c36d35
BZ
35static struct freq_attr *cpufreq_dt_attr[] = {
36 &cpufreq_freq_attr_scaling_available_freqs,
37 NULL, /* Extra space for boost-attr if required */
38 NULL,
39};
40
bbcf0719 41static int set_target(struct cpufreq_policy *policy, unsigned int index)
95ceafd4 42{
d2f31f1d 43 struct private_data *priv = policy->driver_data;
95ceafd4 44
78c3ba5d
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45 return dev_pm_opp_set_rate(priv->cpu_dev,
46 policy->freq_table[index].frequency * 1000);
95ceafd4
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47}
48
050794aa
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49/*
50 * An earlier version of opp-v1 bindings used to name the regulator
51 * "cpu0-supply", we still need to handle that for backwards compatibility.
52 */
df2c8ec2 53static const char *find_supply_name(struct device *dev)
050794aa 54{
df2c8ec2 55 struct device_node *np;
050794aa
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56 struct property *pp;
57 int cpu = dev->id;
df2c8ec2
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58 const char *name = NULL;
59
60 np = of_node_get(dev->of_node);
61
62 /* This must be valid for sure */
63 if (WARN_ON(!np))
64 return NULL;
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65
66 /* Try "cpu0" for older DTs */
67 if (!cpu) {
68 pp = of_find_property(np, "cpu0-supply", NULL);
df2c8ec2
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69 if (pp) {
70 name = "cpu0";
71 goto node_put;
72 }
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73 }
74
75 pp = of_find_property(np, "cpu-supply", NULL);
df2c8ec2
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76 if (pp) {
77 name = "cpu";
78 goto node_put;
79 }
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80
81 dev_dbg(dev, "no regulator for cpu%d\n", cpu);
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82node_put:
83 of_node_put(np);
84 return name;
050794aa
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85}
86
dd02a3d9 87static int resources_available(void)
95ceafd4 88{
d2f31f1d
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89 struct device *cpu_dev;
90 struct regulator *cpu_reg;
91 struct clk *cpu_clk;
92 int ret = 0;
dd02a3d9 93 const char *name;
95ceafd4 94
dd02a3d9 95 cpu_dev = get_cpu_device(0);
e1825b25 96 if (!cpu_dev) {
dd02a3d9 97 pr_err("failed to get cpu0 device\n");
e1825b25
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98 return -ENODEV;
99 }
6754f556 100
dd02a3d9
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101 cpu_clk = clk_get(cpu_dev, NULL);
102 ret = PTR_ERR_OR_ZERO(cpu_clk);
b331bc20 103 if (ret) {
fc31d6f5 104 /*
dd02a3d9
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105 * If cpu's clk node is present, but clock is not yet
106 * registered, we should try defering probe.
fc31d6f5 107 */
dd02a3d9
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108 if (ret == -EPROBE_DEFER)
109 dev_dbg(cpu_dev, "clock not ready, retry\n");
110 else
111 dev_err(cpu_dev, "failed to get clock: %d\n", ret);
2d2c5e0e 112
dd02a3d9 113 return ret;
fc31d6f5
NM
114 }
115
dd02a3d9
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116 clk_put(cpu_clk);
117
118 name = find_supply_name(cpu_dev);
119 /* Platform doesn't require regulator */
120 if (!name)
121 return 0;
d2f31f1d 122
dd02a3d9
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123 cpu_reg = regulator_get_optional(cpu_dev, name);
124 ret = PTR_ERR_OR_ZERO(cpu_reg);
125 if (ret) {
48a8624b 126 /*
dd02a3d9
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127 * If cpu's regulator supply node is present, but regulator is
128 * not yet registered, we should try defering probe.
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129 */
130 if (ret == -EPROBE_DEFER)
dd02a3d9 131 dev_dbg(cpu_dev, "cpu0 regulator not ready, retry\n");
48a8624b 132 else
dd02a3d9
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133 dev_dbg(cpu_dev, "no regulator for cpu0: %d\n", ret);
134
135 return ret;
d2f31f1d
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136 }
137
dd02a3d9
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138 regulator_put(cpu_reg);
139 return 0;
d2f31f1d
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140}
141
bbcf0719 142static int cpufreq_init(struct cpufreq_policy *policy)
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143{
144 struct cpufreq_frequency_table *freq_table;
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145 struct private_data *priv;
146 struct device *cpu_dev;
d2f31f1d 147 struct clk *cpu_clk;
953ba9ff 148 struct dev_pm_opp *suspend_opp;
d2f31f1d 149 unsigned int transition_latency;
457e99e6 150 bool opp_v1 = false;
050794aa 151 const char *name;
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152 int ret;
153
dd02a3d9
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154 cpu_dev = get_cpu_device(policy->cpu);
155 if (!cpu_dev) {
156 pr_err("failed to get cpu%d device\n", policy->cpu);
157 return -ENODEV;
158 }
159
160 cpu_clk = clk_get(cpu_dev, NULL);
161 if (IS_ERR(cpu_clk)) {
162 ret = PTR_ERR(cpu_clk);
163 dev_err(cpu_dev, "%s: failed to get clk: %d\n", __func__, ret);
d2f31f1d
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164 return ret;
165 }
48a8624b 166
2e02d872 167 /* Get OPP-sharing information from "operating-points-v2" bindings */
8f8d37b2 168 ret = dev_pm_opp_of_get_sharing_cpus(cpu_dev, policy->cpus);
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169 if (ret) {
170 /*
171 * operating-points-v2 not supported, fallback to old method of
172 * finding shared-OPPs for backward compatibility.
173 */
174 if (ret == -ENOENT)
457e99e6 175 opp_v1 = true;
2e02d872 176 else
dd02a3d9 177 goto out_put_clk;
2e02d872
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178 }
179
050794aa
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180 /*
181 * OPP layer will be taking care of regulators now, but it needs to know
182 * the name of the regulator first.
183 */
df2c8ec2 184 name = find_supply_name(cpu_dev);
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185 if (name) {
186 ret = dev_pm_opp_set_regulator(cpu_dev, name);
187 if (ret) {
188 dev_err(cpu_dev, "Failed to set regulator for cpu%d: %d\n",
189 policy->cpu, ret);
dd02a3d9 190 goto out_put_clk;
050794aa
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191 }
192 }
193
2e02d872
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194 /*
195 * Initialize OPP tables for all policy->cpus. They will be shared by
196 * all CPUs which have marked their CPUs shared with OPP bindings.
197 *
198 * For platforms not using operating-points-v2 bindings, we do this
199 * before updating policy->cpus. Otherwise, we will end up creating
200 * duplicate OPPs for policy->cpus.
201 *
202 * OPPs might be populated at runtime, don't check for error here
203 */
8f8d37b2 204 dev_pm_opp_of_cpumask_add_table(policy->cpus);
2e02d872 205
7d5d0c8b
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206 /*
207 * But we need OPP table to function so if it is not there let's
208 * give platform code chance to provide it for us.
209 */
210 ret = dev_pm_opp_get_opp_count(cpu_dev);
211 if (ret <= 0) {
896d6a4c 212 dev_dbg(cpu_dev, "OPP table is not ready, deferring probe\n");
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213 ret = -EPROBE_DEFER;
214 goto out_free_opp;
215 }
216
457e99e6 217 if (opp_v1) {
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218 struct cpufreq_dt_platform_data *pd = cpufreq_get_driver_data();
219
220 if (!pd || !pd->independent_clocks)
221 cpumask_setall(policy->cpus);
222
223 /*
224 * OPP tables are initialized only for policy->cpu, do it for
225 * others as well.
226 */
8f8d37b2 227 ret = dev_pm_opp_set_sharing_cpus(cpu_dev, policy->cpus);
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228 if (ret)
229 dev_err(cpu_dev, "%s: failed to mark OPPs as shared: %d\n",
230 __func__, ret);
2e02d872 231 }
95ceafd4 232
d2f31f1d
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233 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
234 if (!priv) {
235 ret = -ENOMEM;
2f0f609f 236 goto out_free_opp;
95ceafd4
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237 }
238
050794aa 239 priv->reg_name = name;
95ceafd4 240
045ee45c
LS
241 ret = dev_pm_opp_init_cpufreq_table(cpu_dev, &freq_table);
242 if (ret) {
896d6a4c 243 dev_err(cpu_dev, "failed to init cpufreq table: %d\n", ret);
045ee45c
LS
244 goto out_free_priv;
245 }
246
d2f31f1d 247 priv->cpu_dev = cpu_dev;
d2f31f1d 248 policy->driver_data = priv;
d2f31f1d 249 policy->clk = cpu_clk;
953ba9ff
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250
251 rcu_read_lock();
252 suspend_opp = dev_pm_opp_get_suspend_opp(cpu_dev);
253 if (suspend_opp)
254 policy->suspend_freq = dev_pm_opp_get_freq(suspend_opp) / 1000;
255 rcu_read_unlock();
256
34e5a527
TP
257 ret = cpufreq_table_validate_and_show(policy, freq_table);
258 if (ret) {
259 dev_err(cpu_dev, "%s: invalid frequency table: %d\n", __func__,
260 ret);
9a004428 261 goto out_free_cpufreq_table;
d15fa862
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262 }
263
264 /* Support turbo/boost mode */
265 if (policy_has_boost_freq(policy)) {
266 /* This gets disabled by core on driver unregister */
267 ret = cpufreq_enable_boost_support();
268 if (ret)
269 goto out_free_cpufreq_table;
21c36d35 270 cpufreq_dt_attr[1] = &cpufreq_freq_attr_scaling_boost_freqs;
34e5a527
TP
271 }
272
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273 transition_latency = dev_pm_opp_get_max_transition_latency(cpu_dev);
274 if (!transition_latency)
275 transition_latency = CPUFREQ_ETERNAL;
276
34e5a527
TP
277 policy->cpuinfo.transition_latency = transition_latency;
278
95ceafd4
SG
279 return 0;
280
9a004428 281out_free_cpufreq_table:
5d4879cd 282 dev_pm_opp_free_cpufreq_table(cpu_dev, &freq_table);
045ee45c
LS
283out_free_priv:
284 kfree(priv);
2f0f609f 285out_free_opp:
8f8d37b2 286 dev_pm_opp_of_cpumask_remove_table(policy->cpus);
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287 if (name)
288 dev_pm_opp_put_regulator(cpu_dev);
dd02a3d9 289out_put_clk:
ed4b053c 290 clk_put(cpu_clk);
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291
292 return ret;
293}
294
bbcf0719 295static int cpufreq_exit(struct cpufreq_policy *policy)
d2f31f1d
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296{
297 struct private_data *priv = policy->driver_data;
298
17ad13ba 299 cpufreq_cooling_unregister(priv->cdev);
d2f31f1d 300 dev_pm_opp_free_cpufreq_table(priv->cpu_dev, &policy->freq_table);
8f8d37b2 301 dev_pm_opp_of_cpumask_remove_table(policy->related_cpus);
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302 if (priv->reg_name)
303 dev_pm_opp_put_regulator(priv->cpu_dev);
304
d2f31f1d 305 clk_put(policy->clk);
d2f31f1d
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306 kfree(priv);
307
308 return 0;
309}
310
9a004428
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311static void cpufreq_ready(struct cpufreq_policy *policy)
312{
313 struct private_data *priv = policy->driver_data;
314 struct device_node *np = of_node_get(priv->cpu_dev->of_node);
315
316 if (WARN_ON(!np))
317 return;
318
319 /*
320 * For now, just loading the cooling device;
321 * thermal DT code takes care of matching them.
322 */
323 if (of_find_property(np, "#cooling-cells", NULL)) {
f8fa8ae0
PA
324 u32 power_coefficient = 0;
325
326 of_property_read_u32(np, "dynamic-power-coefficient",
327 &power_coefficient);
328
329 priv->cdev = of_cpufreq_power_cooling_register(np,
330 policy->related_cpus, power_coefficient, NULL);
9a004428
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331 if (IS_ERR(priv->cdev)) {
332 dev_err(priv->cpu_dev,
333 "running cpufreq without cooling device: %ld\n",
334 PTR_ERR(priv->cdev));
335
336 priv->cdev = NULL;
337 }
338 }
339
340 of_node_put(np);
341}
342
bbcf0719 343static struct cpufreq_driver dt_cpufreq_driver = {
d2f31f1d
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344 .flags = CPUFREQ_STICKY | CPUFREQ_NEED_INITIAL_FREQ_CHECK,
345 .verify = cpufreq_generic_frequency_table_verify,
bbcf0719 346 .target_index = set_target,
d2f31f1d 347 .get = cpufreq_generic_get,
bbcf0719
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348 .init = cpufreq_init,
349 .exit = cpufreq_exit,
9a004428 350 .ready = cpufreq_ready,
bbcf0719 351 .name = "cpufreq-dt",
21c36d35 352 .attr = cpufreq_dt_attr,
953ba9ff 353 .suspend = cpufreq_generic_suspend,
d2f31f1d
VK
354};
355
bbcf0719 356static int dt_cpufreq_probe(struct platform_device *pdev)
d2f31f1d 357{
d2f31f1d
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358 int ret;
359
360 /*
361 * All per-cluster (CPUs sharing clock/voltages) initialization is done
362 * from ->init(). In probe(), we just need to make sure that clk and
363 * regulators are available. Else defer probe and retry.
364 *
365 * FIXME: Is checking this only for CPU0 sufficient ?
366 */
dd02a3d9 367 ret = resources_available();
d2f31f1d
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368 if (ret)
369 return ret;
370
34e5a527
TP
371 dt_cpufreq_driver.driver_data = dev_get_platdata(&pdev->dev);
372
bbcf0719 373 ret = cpufreq_register_driver(&dt_cpufreq_driver);
d2f31f1d 374 if (ret)
dd02a3d9 375 dev_err(&pdev->dev, "failed register driver: %d\n", ret);
d2f31f1d 376
95ceafd4
SG
377 return ret;
378}
5553f9e2 379
bbcf0719 380static int dt_cpufreq_remove(struct platform_device *pdev)
5553f9e2 381{
bbcf0719 382 cpufreq_unregister_driver(&dt_cpufreq_driver);
5553f9e2
SG
383 return 0;
384}
385
bbcf0719 386static struct platform_driver dt_cpufreq_platdrv = {
5553f9e2 387 .driver = {
bbcf0719 388 .name = "cpufreq-dt",
5553f9e2 389 },
bbcf0719
VK
390 .probe = dt_cpufreq_probe,
391 .remove = dt_cpufreq_remove,
5553f9e2 392};
bbcf0719 393module_platform_driver(dt_cpufreq_platdrv);
95ceafd4 394
07949bf9 395MODULE_ALIAS("platform:cpufreq-dt");
748c8766 396MODULE_AUTHOR("Viresh Kumar <viresh.kumar@linaro.org>");
95ceafd4 397MODULE_AUTHOR("Shawn Guo <shawn.guo@linaro.org>");
bbcf0719 398MODULE_DESCRIPTION("Generic cpufreq driver");
95ceafd4 399MODULE_LICENSE("GPL");