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1 | // SPDX-License-Identifier: GPL-2.0 | |
2 | /* | |
3 | * linux/drivers/thermal/cpu_cooling.c | |
4 | * | |
5 | * Copyright (C) 2012 Samsung Electronics Co., Ltd(http://www.samsung.com) | |
6 | * | |
7 | * Copyright (C) 2012-2018 Linaro Limited. | |
8 | * | |
9 | * Authors: Amit Daniel <amit.kachhap@linaro.org> | |
10 | * Viresh Kumar <viresh.kumar@linaro.org> | |
11 | * | |
12 | */ | |
13 | #include <linux/module.h> | |
14 | #include <linux/thermal.h> | |
15 | #include <linux/cpufreq.h> | |
16 | #include <linux/err.h> | |
17 | #include <linux/idr.h> | |
18 | #include <linux/pm_opp.h> | |
19 | #include <linux/pm_qos.h> | |
20 | #include <linux/slab.h> | |
21 | #include <linux/cpu.h> | |
22 | #include <linux/cpu_cooling.h> | |
23 | ||
24 | #include <trace/events/thermal.h> | |
25 | ||
26 | /* | |
27 | * Cooling state <-> CPUFreq frequency | |
28 | * | |
29 | * Cooling states are translated to frequencies throughout this driver and this | |
30 | * is the relation between them. | |
31 | * | |
32 | * Highest cooling state corresponds to lowest possible frequency. | |
33 | * | |
34 | * i.e. | |
35 | * level 0 --> 1st Max Freq | |
36 | * level 1 --> 2nd Max Freq | |
37 | * ... | |
38 | */ | |
39 | ||
40 | /** | |
41 | * struct freq_table - frequency table along with power entries | |
42 | * @frequency: frequency in KHz | |
43 | * @power: power in mW | |
44 | * | |
45 | * This structure is built when the cooling device registers and helps | |
46 | * in translating frequency to power and vice versa. | |
47 | */ | |
48 | struct freq_table { | |
49 | u32 frequency; | |
50 | u32 power; | |
51 | }; | |
52 | ||
53 | /** | |
54 | * struct time_in_idle - Idle time stats | |
55 | * @time: previous reading of the absolute time that this cpu was idle | |
56 | * @timestamp: wall time of the last invocation of get_cpu_idle_time_us() | |
57 | */ | |
58 | struct time_in_idle { | |
59 | u64 time; | |
60 | u64 timestamp; | |
61 | }; | |
62 | ||
63 | /** | |
64 | * struct cpufreq_cooling_device - data for cooling device with cpufreq | |
65 | * @id: unique integer value corresponding to each cpufreq_cooling_device | |
66 | * registered. | |
67 | * @last_load: load measured by the latest call to cpufreq_get_requested_power() | |
68 | * @cpufreq_state: integer value representing the current state of cpufreq | |
69 | * cooling devices. | |
70 | * @max_level: maximum cooling level. One less than total number of valid | |
71 | * cpufreq frequencies. | |
72 | * @freq_table: Freq table in descending order of frequencies | |
73 | * @cdev: thermal_cooling_device pointer to keep track of the | |
74 | * registered cooling device. | |
75 | * @policy: cpufreq policy. | |
76 | * @node: list_head to link all cpufreq_cooling_device together. | |
77 | * @idle_time: idle time stats | |
78 | * | |
79 | * This structure is required for keeping information of each registered | |
80 | * cpufreq_cooling_device. | |
81 | */ | |
82 | struct cpufreq_cooling_device { | |
83 | int id; | |
84 | u32 last_load; | |
85 | unsigned int cpufreq_state; | |
86 | unsigned int max_level; | |
87 | struct freq_table *freq_table; /* In descending order */ | |
88 | struct cpufreq_policy *policy; | |
89 | struct list_head node; | |
90 | struct time_in_idle *idle_time; | |
91 | struct dev_pm_qos_request qos_req; | |
92 | }; | |
93 | ||
94 | static DEFINE_IDA(cpufreq_ida); | |
95 | static DEFINE_MUTEX(cooling_list_lock); | |
96 | static LIST_HEAD(cpufreq_cdev_list); | |
97 | ||
98 | /* Below code defines functions to be used for cpufreq as cooling device */ | |
99 | ||
100 | /** | |
101 | * get_level: Find the level for a particular frequency | |
102 | * @cpufreq_cdev: cpufreq_cdev for which the property is required | |
103 | * @freq: Frequency | |
104 | * | |
105 | * Return: level corresponding to the frequency. | |
106 | */ | |
107 | static unsigned long get_level(struct cpufreq_cooling_device *cpufreq_cdev, | |
108 | unsigned int freq) | |
109 | { | |
110 | struct freq_table *freq_table = cpufreq_cdev->freq_table; | |
111 | unsigned long level; | |
112 | ||
113 | for (level = 1; level <= cpufreq_cdev->max_level; level++) | |
114 | if (freq > freq_table[level].frequency) | |
115 | break; | |
116 | ||
117 | return level - 1; | |
118 | } | |
119 | ||
120 | /** | |
121 | * update_freq_table() - Update the freq table with power numbers | |
122 | * @cpufreq_cdev: the cpufreq cooling device in which to update the table | |
123 | * @capacitance: dynamic power coefficient for these cpus | |
124 | * | |
125 | * Update the freq table with power numbers. This table will be used in | |
126 | * cpu_power_to_freq() and cpu_freq_to_power() to convert between power and | |
127 | * frequency efficiently. Power is stored in mW, frequency in KHz. The | |
128 | * resulting table is in descending order. | |
129 | * | |
130 | * Return: 0 on success, -EINVAL if there are no OPPs for any CPUs, | |
131 | * or -ENOMEM if we run out of memory. | |
132 | */ | |
133 | static int update_freq_table(struct cpufreq_cooling_device *cpufreq_cdev, | |
134 | u32 capacitance) | |
135 | { | |
136 | struct freq_table *freq_table = cpufreq_cdev->freq_table; | |
137 | struct dev_pm_opp *opp; | |
138 | struct device *dev = NULL; | |
139 | int num_opps = 0, cpu = cpufreq_cdev->policy->cpu, i; | |
140 | ||
141 | dev = get_cpu_device(cpu); | |
142 | if (unlikely(!dev)) { | |
143 | pr_warn("No cpu device for cpu %d\n", cpu); | |
144 | return -ENODEV; | |
145 | } | |
146 | ||
147 | num_opps = dev_pm_opp_get_opp_count(dev); | |
148 | if (num_opps < 0) | |
149 | return num_opps; | |
150 | ||
151 | /* | |
152 | * The cpufreq table is also built from the OPP table and so the count | |
153 | * should match. | |
154 | */ | |
155 | if (num_opps != cpufreq_cdev->max_level + 1) { | |
156 | dev_warn(dev, "Number of OPPs not matching with max_levels\n"); | |
157 | return -EINVAL; | |
158 | } | |
159 | ||
160 | for (i = 0; i <= cpufreq_cdev->max_level; i++) { | |
161 | unsigned long freq = freq_table[i].frequency * 1000; | |
162 | u32 freq_mhz = freq_table[i].frequency / 1000; | |
163 | u64 power; | |
164 | u32 voltage_mv; | |
165 | ||
166 | /* | |
167 | * Find ceil frequency as 'freq' may be slightly lower than OPP | |
168 | * freq due to truncation while converting to kHz. | |
169 | */ | |
170 | opp = dev_pm_opp_find_freq_ceil(dev, &freq); | |
171 | if (IS_ERR(opp)) { | |
172 | dev_err(dev, "failed to get opp for %lu frequency\n", | |
173 | freq); | |
174 | return -EINVAL; | |
175 | } | |
176 | ||
177 | voltage_mv = dev_pm_opp_get_voltage(opp) / 1000; | |
178 | dev_pm_opp_put(opp); | |
179 | ||
180 | /* | |
181 | * Do the multiplication with MHz and millivolt so as | |
182 | * to not overflow. | |
183 | */ | |
184 | power = (u64)capacitance * freq_mhz * voltage_mv * voltage_mv; | |
185 | do_div(power, 1000000000); | |
186 | ||
187 | /* power is stored in mW */ | |
188 | freq_table[i].power = power; | |
189 | } | |
190 | ||
191 | return 0; | |
192 | } | |
193 | ||
194 | static u32 cpu_freq_to_power(struct cpufreq_cooling_device *cpufreq_cdev, | |
195 | u32 freq) | |
196 | { | |
197 | int i; | |
198 | struct freq_table *freq_table = cpufreq_cdev->freq_table; | |
199 | ||
200 | for (i = 1; i <= cpufreq_cdev->max_level; i++) | |
201 | if (freq > freq_table[i].frequency) | |
202 | break; | |
203 | ||
204 | return freq_table[i - 1].power; | |
205 | } | |
206 | ||
207 | static u32 cpu_power_to_freq(struct cpufreq_cooling_device *cpufreq_cdev, | |
208 | u32 power) | |
209 | { | |
210 | int i; | |
211 | struct freq_table *freq_table = cpufreq_cdev->freq_table; | |
212 | ||
213 | for (i = 1; i <= cpufreq_cdev->max_level; i++) | |
214 | if (power > freq_table[i].power) | |
215 | break; | |
216 | ||
217 | return freq_table[i - 1].frequency; | |
218 | } | |
219 | ||
220 | /** | |
221 | * get_load() - get load for a cpu since last updated | |
222 | * @cpufreq_cdev: &struct cpufreq_cooling_device for this cpu | |
223 | * @cpu: cpu number | |
224 | * @cpu_idx: index of the cpu in time_in_idle* | |
225 | * | |
226 | * Return: The average load of cpu @cpu in percentage since this | |
227 | * function was last called. | |
228 | */ | |
229 | static u32 get_load(struct cpufreq_cooling_device *cpufreq_cdev, int cpu, | |
230 | int cpu_idx) | |
231 | { | |
232 | u32 load; | |
233 | u64 now, now_idle, delta_time, delta_idle; | |
234 | struct time_in_idle *idle_time = &cpufreq_cdev->idle_time[cpu_idx]; | |
235 | ||
236 | now_idle = get_cpu_idle_time(cpu, &now, 0); | |
237 | delta_idle = now_idle - idle_time->time; | |
238 | delta_time = now - idle_time->timestamp; | |
239 | ||
240 | if (delta_time <= delta_idle) | |
241 | load = 0; | |
242 | else | |
243 | load = div64_u64(100 * (delta_time - delta_idle), delta_time); | |
244 | ||
245 | idle_time->time = now_idle; | |
246 | idle_time->timestamp = now; | |
247 | ||
248 | return load; | |
249 | } | |
250 | ||
251 | /** | |
252 | * get_dynamic_power() - calculate the dynamic power | |
253 | * @cpufreq_cdev: &cpufreq_cooling_device for this cdev | |
254 | * @freq: current frequency | |
255 | * | |
256 | * Return: the dynamic power consumed by the cpus described by | |
257 | * @cpufreq_cdev. | |
258 | */ | |
259 | static u32 get_dynamic_power(struct cpufreq_cooling_device *cpufreq_cdev, | |
260 | unsigned long freq) | |
261 | { | |
262 | u32 raw_cpu_power; | |
263 | ||
264 | raw_cpu_power = cpu_freq_to_power(cpufreq_cdev, freq); | |
265 | return (raw_cpu_power * cpufreq_cdev->last_load) / 100; | |
266 | } | |
267 | ||
268 | /* cpufreq cooling device callback functions are defined below */ | |
269 | ||
270 | /** | |
271 | * cpufreq_get_max_state - callback function to get the max cooling state. | |
272 | * @cdev: thermal cooling device pointer. | |
273 | * @state: fill this variable with the max cooling state. | |
274 | * | |
275 | * Callback for the thermal cooling device to return the cpufreq | |
276 | * max cooling state. | |
277 | * | |
278 | * Return: 0 on success, an error code otherwise. | |
279 | */ | |
280 | static int cpufreq_get_max_state(struct thermal_cooling_device *cdev, | |
281 | unsigned long *state) | |
282 | { | |
283 | struct cpufreq_cooling_device *cpufreq_cdev = cdev->devdata; | |
284 | ||
285 | *state = cpufreq_cdev->max_level; | |
286 | return 0; | |
287 | } | |
288 | ||
289 | /** | |
290 | * cpufreq_get_cur_state - callback function to get the current cooling state. | |
291 | * @cdev: thermal cooling device pointer. | |
292 | * @state: fill this variable with the current cooling state. | |
293 | * | |
294 | * Callback for the thermal cooling device to return the cpufreq | |
295 | * current cooling state. | |
296 | * | |
297 | * Return: 0 on success, an error code otherwise. | |
298 | */ | |
299 | static int cpufreq_get_cur_state(struct thermal_cooling_device *cdev, | |
300 | unsigned long *state) | |
301 | { | |
302 | struct cpufreq_cooling_device *cpufreq_cdev = cdev->devdata; | |
303 | ||
304 | *state = cpufreq_cdev->cpufreq_state; | |
305 | ||
306 | return 0; | |
307 | } | |
308 | ||
309 | /** | |
310 | * cpufreq_set_cur_state - callback function to set the current cooling state. | |
311 | * @cdev: thermal cooling device pointer. | |
312 | * @state: set this variable to the current cooling state. | |
313 | * | |
314 | * Callback for the thermal cooling device to change the cpufreq | |
315 | * current cooling state. | |
316 | * | |
317 | * Return: 0 on success, an error code otherwise. | |
318 | */ | |
319 | static int cpufreq_set_cur_state(struct thermal_cooling_device *cdev, | |
320 | unsigned long state) | |
321 | { | |
322 | struct cpufreq_cooling_device *cpufreq_cdev = cdev->devdata; | |
323 | ||
324 | /* Request state should be less than max_level */ | |
325 | if (WARN_ON(state > cpufreq_cdev->max_level)) | |
326 | return -EINVAL; | |
327 | ||
328 | /* Check if the old cooling action is same as new cooling action */ | |
329 | if (cpufreq_cdev->cpufreq_state == state) | |
330 | return 0; | |
331 | ||
332 | cpufreq_cdev->cpufreq_state = state; | |
333 | ||
334 | return dev_pm_qos_update_request(&cpufreq_cdev->qos_req, | |
335 | cpufreq_cdev->freq_table[state].frequency); | |
336 | } | |
337 | ||
338 | /** | |
339 | * cpufreq_get_requested_power() - get the current power | |
340 | * @cdev: &thermal_cooling_device pointer | |
341 | * @tz: a valid thermal zone device pointer | |
342 | * @power: pointer in which to store the resulting power | |
343 | * | |
344 | * Calculate the current power consumption of the cpus in milliwatts | |
345 | * and store it in @power. This function should actually calculate | |
346 | * the requested power, but it's hard to get the frequency that | |
347 | * cpufreq would have assigned if there were no thermal limits. | |
348 | * Instead, we calculate the current power on the assumption that the | |
349 | * immediate future will look like the immediate past. | |
350 | * | |
351 | * We use the current frequency and the average load since this | |
352 | * function was last called. In reality, there could have been | |
353 | * multiple opps since this function was last called and that affects | |
354 | * the load calculation. While it's not perfectly accurate, this | |
355 | * simplification is good enough and works. REVISIT this, as more | |
356 | * complex code may be needed if experiments show that it's not | |
357 | * accurate enough. | |
358 | * | |
359 | * Return: 0 on success, -E* if getting the static power failed. | |
360 | */ | |
361 | static int cpufreq_get_requested_power(struct thermal_cooling_device *cdev, | |
362 | struct thermal_zone_device *tz, | |
363 | u32 *power) | |
364 | { | |
365 | unsigned long freq; | |
366 | int i = 0, cpu; | |
367 | u32 total_load = 0; | |
368 | struct cpufreq_cooling_device *cpufreq_cdev = cdev->devdata; | |
369 | struct cpufreq_policy *policy = cpufreq_cdev->policy; | |
370 | u32 *load_cpu = NULL; | |
371 | ||
372 | freq = cpufreq_quick_get(policy->cpu); | |
373 | ||
374 | if (trace_thermal_power_cpu_get_power_enabled()) { | |
375 | u32 ncpus = cpumask_weight(policy->related_cpus); | |
376 | ||
377 | load_cpu = kcalloc(ncpus, sizeof(*load_cpu), GFP_KERNEL); | |
378 | } | |
379 | ||
380 | for_each_cpu(cpu, policy->related_cpus) { | |
381 | u32 load; | |
382 | ||
383 | if (cpu_online(cpu)) | |
384 | load = get_load(cpufreq_cdev, cpu, i); | |
385 | else | |
386 | load = 0; | |
387 | ||
388 | total_load += load; | |
389 | if (load_cpu) | |
390 | load_cpu[i] = load; | |
391 | ||
392 | i++; | |
393 | } | |
394 | ||
395 | cpufreq_cdev->last_load = total_load; | |
396 | ||
397 | *power = get_dynamic_power(cpufreq_cdev, freq); | |
398 | ||
399 | if (load_cpu) { | |
400 | trace_thermal_power_cpu_get_power(policy->related_cpus, freq, | |
401 | load_cpu, i, *power); | |
402 | ||
403 | kfree(load_cpu); | |
404 | } | |
405 | ||
406 | return 0; | |
407 | } | |
408 | ||
409 | /** | |
410 | * cpufreq_state2power() - convert a cpu cdev state to power consumed | |
411 | * @cdev: &thermal_cooling_device pointer | |
412 | * @tz: a valid thermal zone device pointer | |
413 | * @state: cooling device state to be converted | |
414 | * @power: pointer in which to store the resulting power | |
415 | * | |
416 | * Convert cooling device state @state into power consumption in | |
417 | * milliwatts assuming 100% load. Store the calculated power in | |
418 | * @power. | |
419 | * | |
420 | * Return: 0 on success, -EINVAL if the cooling device state could not | |
421 | * be converted into a frequency or other -E* if there was an error | |
422 | * when calculating the static power. | |
423 | */ | |
424 | static int cpufreq_state2power(struct thermal_cooling_device *cdev, | |
425 | struct thermal_zone_device *tz, | |
426 | unsigned long state, u32 *power) | |
427 | { | |
428 | unsigned int freq, num_cpus; | |
429 | struct cpufreq_cooling_device *cpufreq_cdev = cdev->devdata; | |
430 | ||
431 | /* Request state should be less than max_level */ | |
432 | if (WARN_ON(state > cpufreq_cdev->max_level)) | |
433 | return -EINVAL; | |
434 | ||
435 | num_cpus = cpumask_weight(cpufreq_cdev->policy->cpus); | |
436 | ||
437 | freq = cpufreq_cdev->freq_table[state].frequency; | |
438 | *power = cpu_freq_to_power(cpufreq_cdev, freq) * num_cpus; | |
439 | ||
440 | return 0; | |
441 | } | |
442 | ||
443 | /** | |
444 | * cpufreq_power2state() - convert power to a cooling device state | |
445 | * @cdev: &thermal_cooling_device pointer | |
446 | * @tz: a valid thermal zone device pointer | |
447 | * @power: power in milliwatts to be converted | |
448 | * @state: pointer in which to store the resulting state | |
449 | * | |
450 | * Calculate a cooling device state for the cpus described by @cdev | |
451 | * that would allow them to consume at most @power mW and store it in | |
452 | * @state. Note that this calculation depends on external factors | |
453 | * such as the cpu load or the current static power. Calling this | |
454 | * function with the same power as input can yield different cooling | |
455 | * device states depending on those external factors. | |
456 | * | |
457 | * Return: 0 on success, -ENODEV if no cpus are online or -EINVAL if | |
458 | * the calculated frequency could not be converted to a valid state. | |
459 | * The latter should not happen unless the frequencies available to | |
460 | * cpufreq have changed since the initialization of the cpu cooling | |
461 | * device. | |
462 | */ | |
463 | static int cpufreq_power2state(struct thermal_cooling_device *cdev, | |
464 | struct thermal_zone_device *tz, u32 power, | |
465 | unsigned long *state) | |
466 | { | |
467 | unsigned int target_freq; | |
468 | u32 last_load, normalised_power; | |
469 | struct cpufreq_cooling_device *cpufreq_cdev = cdev->devdata; | |
470 | struct cpufreq_policy *policy = cpufreq_cdev->policy; | |
471 | ||
472 | last_load = cpufreq_cdev->last_load ?: 1; | |
473 | normalised_power = (power * 100) / last_load; | |
474 | target_freq = cpu_power_to_freq(cpufreq_cdev, normalised_power); | |
475 | ||
476 | *state = get_level(cpufreq_cdev, target_freq); | |
477 | trace_thermal_power_cpu_limit(policy->related_cpus, target_freq, *state, | |
478 | power); | |
479 | return 0; | |
480 | } | |
481 | ||
482 | /* Bind cpufreq callbacks to thermal cooling device ops */ | |
483 | ||
484 | static struct thermal_cooling_device_ops cpufreq_cooling_ops = { | |
485 | .get_max_state = cpufreq_get_max_state, | |
486 | .get_cur_state = cpufreq_get_cur_state, | |
487 | .set_cur_state = cpufreq_set_cur_state, | |
488 | }; | |
489 | ||
490 | static struct thermal_cooling_device_ops cpufreq_power_cooling_ops = { | |
491 | .get_max_state = cpufreq_get_max_state, | |
492 | .get_cur_state = cpufreq_get_cur_state, | |
493 | .set_cur_state = cpufreq_set_cur_state, | |
494 | .get_requested_power = cpufreq_get_requested_power, | |
495 | .state2power = cpufreq_state2power, | |
496 | .power2state = cpufreq_power2state, | |
497 | }; | |
498 | ||
499 | static unsigned int find_next_max(struct cpufreq_frequency_table *table, | |
500 | unsigned int prev_max) | |
501 | { | |
502 | struct cpufreq_frequency_table *pos; | |
503 | unsigned int max = 0; | |
504 | ||
505 | cpufreq_for_each_valid_entry(pos, table) { | |
506 | if (pos->frequency > max && pos->frequency < prev_max) | |
507 | max = pos->frequency; | |
508 | } | |
509 | ||
510 | return max; | |
511 | } | |
512 | ||
513 | /** | |
514 | * __cpufreq_cooling_register - helper function to create cpufreq cooling device | |
515 | * @np: a valid struct device_node to the cooling device device tree node | |
516 | * @policy: cpufreq policy | |
517 | * Normally this should be same as cpufreq policy->related_cpus. | |
518 | * @capacitance: dynamic power coefficient for these cpus | |
519 | * | |
520 | * This interface function registers the cpufreq cooling device with the name | |
521 | * "thermal-cpufreq-%x". This api can support multiple instances of cpufreq | |
522 | * cooling devices. It also gives the opportunity to link the cooling device | |
523 | * with a device tree node, in order to bind it via the thermal DT code. | |
524 | * | |
525 | * Return: a valid struct thermal_cooling_device pointer on success, | |
526 | * on failure, it returns a corresponding ERR_PTR(). | |
527 | */ | |
528 | static struct thermal_cooling_device * | |
529 | __cpufreq_cooling_register(struct device_node *np, | |
530 | struct cpufreq_policy *policy, u32 capacitance) | |
531 | { | |
532 | struct thermal_cooling_device *cdev; | |
533 | struct cpufreq_cooling_device *cpufreq_cdev; | |
534 | char dev_name[THERMAL_NAME_LENGTH]; | |
535 | unsigned int freq, i, num_cpus; | |
536 | struct device *dev; | |
537 | int ret; | |
538 | struct thermal_cooling_device_ops *cooling_ops; | |
539 | ||
540 | dev = get_cpu_device(policy->cpu); | |
541 | if (unlikely(!dev)) { | |
542 | pr_warn("No cpu device for cpu %d\n", policy->cpu); | |
543 | return ERR_PTR(-ENODEV); | |
544 | } | |
545 | ||
546 | ||
547 | if (IS_ERR_OR_NULL(policy)) { | |
548 | pr_err("%s: cpufreq policy isn't valid: %p\n", __func__, policy); | |
549 | return ERR_PTR(-EINVAL); | |
550 | } | |
551 | ||
552 | i = cpufreq_table_count_valid_entries(policy); | |
553 | if (!i) { | |
554 | pr_debug("%s: CPUFreq table not found or has no valid entries\n", | |
555 | __func__); | |
556 | return ERR_PTR(-ENODEV); | |
557 | } | |
558 | ||
559 | cpufreq_cdev = kzalloc(sizeof(*cpufreq_cdev), GFP_KERNEL); | |
560 | if (!cpufreq_cdev) | |
561 | return ERR_PTR(-ENOMEM); | |
562 | ||
563 | cpufreq_cdev->policy = policy; | |
564 | num_cpus = cpumask_weight(policy->related_cpus); | |
565 | cpufreq_cdev->idle_time = kcalloc(num_cpus, | |
566 | sizeof(*cpufreq_cdev->idle_time), | |
567 | GFP_KERNEL); | |
568 | if (!cpufreq_cdev->idle_time) { | |
569 | cdev = ERR_PTR(-ENOMEM); | |
570 | goto free_cdev; | |
571 | } | |
572 | ||
573 | /* max_level is an index, not a counter */ | |
574 | cpufreq_cdev->max_level = i - 1; | |
575 | ||
576 | cpufreq_cdev->freq_table = kmalloc_array(i, | |
577 | sizeof(*cpufreq_cdev->freq_table), | |
578 | GFP_KERNEL); | |
579 | if (!cpufreq_cdev->freq_table) { | |
580 | cdev = ERR_PTR(-ENOMEM); | |
581 | goto free_idle_time; | |
582 | } | |
583 | ||
584 | ret = ida_simple_get(&cpufreq_ida, 0, 0, GFP_KERNEL); | |
585 | if (ret < 0) { | |
586 | cdev = ERR_PTR(ret); | |
587 | goto free_table; | |
588 | } | |
589 | cpufreq_cdev->id = ret; | |
590 | ||
591 | snprintf(dev_name, sizeof(dev_name), "thermal-cpufreq-%d", | |
592 | cpufreq_cdev->id); | |
593 | ||
594 | /* Fill freq-table in descending order of frequencies */ | |
595 | for (i = 0, freq = -1; i <= cpufreq_cdev->max_level; i++) { | |
596 | freq = find_next_max(policy->freq_table, freq); | |
597 | cpufreq_cdev->freq_table[i].frequency = freq; | |
598 | ||
599 | /* Warn for duplicate entries */ | |
600 | if (!freq) | |
601 | pr_warn("%s: table has duplicate entries\n", __func__); | |
602 | else | |
603 | pr_debug("%s: freq:%u KHz\n", __func__, freq); | |
604 | } | |
605 | ||
606 | if (capacitance) { | |
607 | ret = update_freq_table(cpufreq_cdev, capacitance); | |
608 | if (ret) { | |
609 | cdev = ERR_PTR(ret); | |
610 | goto remove_ida; | |
611 | } | |
612 | ||
613 | cooling_ops = &cpufreq_power_cooling_ops; | |
614 | } else { | |
615 | cooling_ops = &cpufreq_cooling_ops; | |
616 | } | |
617 | ||
618 | ret = dev_pm_qos_add_request(dev, &cpufreq_cdev->qos_req, | |
619 | DEV_PM_QOS_MAX_FREQUENCY, | |
620 | cpufreq_cdev->freq_table[0].frequency); | |
621 | if (ret < 0) { | |
622 | pr_err("%s: Failed to add freq constraint (%d)\n", __func__, | |
623 | ret); | |
624 | cdev = ERR_PTR(ret); | |
625 | goto remove_ida; | |
626 | } | |
627 | ||
628 | cdev = thermal_of_cooling_device_register(np, dev_name, cpufreq_cdev, | |
629 | cooling_ops); | |
630 | if (IS_ERR(cdev)) | |
631 | goto remove_qos_req; | |
632 | ||
633 | mutex_lock(&cooling_list_lock); | |
634 | list_add(&cpufreq_cdev->node, &cpufreq_cdev_list); | |
635 | mutex_unlock(&cooling_list_lock); | |
636 | ||
637 | return cdev; | |
638 | ||
639 | remove_qos_req: | |
640 | dev_pm_qos_remove_request(&cpufreq_cdev->qos_req); | |
641 | remove_ida: | |
642 | ida_simple_remove(&cpufreq_ida, cpufreq_cdev->id); | |
643 | free_table: | |
644 | kfree(cpufreq_cdev->freq_table); | |
645 | free_idle_time: | |
646 | kfree(cpufreq_cdev->idle_time); | |
647 | free_cdev: | |
648 | kfree(cpufreq_cdev); | |
649 | return cdev; | |
650 | } | |
651 | ||
652 | /** | |
653 | * cpufreq_cooling_register - function to create cpufreq cooling device. | |
654 | * @policy: cpufreq policy | |
655 | * | |
656 | * This interface function registers the cpufreq cooling device with the name | |
657 | * "thermal-cpufreq-%x". This api can support multiple instances of cpufreq | |
658 | * cooling devices. | |
659 | * | |
660 | * Return: a valid struct thermal_cooling_device pointer on success, | |
661 | * on failure, it returns a corresponding ERR_PTR(). | |
662 | */ | |
663 | struct thermal_cooling_device * | |
664 | cpufreq_cooling_register(struct cpufreq_policy *policy) | |
665 | { | |
666 | return __cpufreq_cooling_register(NULL, policy, 0); | |
667 | } | |
668 | EXPORT_SYMBOL_GPL(cpufreq_cooling_register); | |
669 | ||
670 | /** | |
671 | * of_cpufreq_cooling_register - function to create cpufreq cooling device. | |
672 | * @policy: cpufreq policy | |
673 | * | |
674 | * This interface function registers the cpufreq cooling device with the name | |
675 | * "thermal-cpufreq-%x". This api can support multiple instances of cpufreq | |
676 | * cooling devices. Using this API, the cpufreq cooling device will be | |
677 | * linked to the device tree node provided. | |
678 | * | |
679 | * Using this function, the cooling device will implement the power | |
680 | * extensions by using a simple cpu power model. The cpus must have | |
681 | * registered their OPPs using the OPP library. | |
682 | * | |
683 | * It also takes into account, if property present in policy CPU node, the | |
684 | * static power consumed by the cpu. | |
685 | * | |
686 | * Return: a valid struct thermal_cooling_device pointer on success, | |
687 | * and NULL on failure. | |
688 | */ | |
689 | struct thermal_cooling_device * | |
690 | of_cpufreq_cooling_register(struct cpufreq_policy *policy) | |
691 | { | |
692 | struct device_node *np = of_get_cpu_node(policy->cpu, NULL); | |
693 | struct thermal_cooling_device *cdev = NULL; | |
694 | u32 capacitance = 0; | |
695 | ||
696 | if (!np) { | |
697 | pr_err("cpu_cooling: OF node not available for cpu%d\n", | |
698 | policy->cpu); | |
699 | return NULL; | |
700 | } | |
701 | ||
702 | if (of_find_property(np, "#cooling-cells", NULL)) { | |
703 | of_property_read_u32(np, "dynamic-power-coefficient", | |
704 | &capacitance); | |
705 | ||
706 | cdev = __cpufreq_cooling_register(np, policy, capacitance); | |
707 | if (IS_ERR(cdev)) { | |
708 | pr_err("cpu_cooling: cpu%d failed to register as cooling device: %ld\n", | |
709 | policy->cpu, PTR_ERR(cdev)); | |
710 | cdev = NULL; | |
711 | } | |
712 | } | |
713 | ||
714 | of_node_put(np); | |
715 | return cdev; | |
716 | } | |
717 | EXPORT_SYMBOL_GPL(of_cpufreq_cooling_register); | |
718 | ||
719 | /** | |
720 | * cpufreq_cooling_unregister - function to remove cpufreq cooling device. | |
721 | * @cdev: thermal cooling device pointer. | |
722 | * | |
723 | * This interface function unregisters the "thermal-cpufreq-%x" cooling device. | |
724 | */ | |
725 | void cpufreq_cooling_unregister(struct thermal_cooling_device *cdev) | |
726 | { | |
727 | struct cpufreq_cooling_device *cpufreq_cdev; | |
728 | ||
729 | if (!cdev) | |
730 | return; | |
731 | ||
732 | cpufreq_cdev = cdev->devdata; | |
733 | ||
734 | mutex_lock(&cooling_list_lock); | |
735 | list_del(&cpufreq_cdev->node); | |
736 | mutex_unlock(&cooling_list_lock); | |
737 | ||
738 | thermal_cooling_device_unregister(cdev); | |
739 | dev_pm_qos_remove_request(&cpufreq_cdev->qos_req); | |
740 | ida_simple_remove(&cpufreq_ida, cpufreq_cdev->id); | |
741 | kfree(cpufreq_cdev->idle_time); | |
742 | kfree(cpufreq_cdev->freq_table); | |
743 | kfree(cpufreq_cdev); | |
744 | } | |
745 | EXPORT_SYMBOL_GPL(cpufreq_cooling_unregister); |