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f47b72a1 VK |
1 | /* |
2 | * Generic OPP OF helpers | |
3 | * | |
4 | * Copyright (C) 2009-2010 Texas Instruments Incorporated. | |
5 | * Nishanth Menon | |
6 | * Romit Dasgupta | |
7 | * Kevin Hilman | |
8 | * | |
9 | * This program is free software; you can redistribute it and/or modify | |
10 | * it under the terms of the GNU General Public License version 2 as | |
11 | * published by the Free Software Foundation. | |
12 | */ | |
13 | ||
14 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt | |
15 | ||
16 | #include <linux/cpu.h> | |
17 | #include <linux/errno.h> | |
18 | #include <linux/device.h> | |
19 | #include <linux/of.h> | |
dfbe4678 | 20 | #include <linux/slab.h> |
f47b72a1 VK |
21 | #include <linux/export.h> |
22 | ||
23 | #include "opp.h" | |
24 | ||
25 | static struct opp_table *_managed_opp(const struct device_node *np) | |
26 | { | |
b83c1899 VK |
27 | struct opp_table *opp_table, *managed_table = NULL; |
28 | ||
29 | mutex_lock(&opp_table_lock); | |
f47b72a1 VK |
30 | |
31 | list_for_each_entry_rcu(opp_table, &opp_tables, node) { | |
32 | if (opp_table->np == np) { | |
33 | /* | |
34 | * Multiple devices can point to the same OPP table and | |
35 | * so will have same node-pointer, np. | |
36 | * | |
37 | * But the OPPs will be considered as shared only if the | |
38 | * OPP table contains a "opp-shared" property. | |
39 | */ | |
b83c1899 VK |
40 | if (opp_table->shared_opp == OPP_TABLE_ACCESS_SHARED) { |
41 | _get_opp_table_kref(opp_table); | |
42 | managed_table = opp_table; | |
43 | } | |
79ee2e8f | 44 | |
b83c1899 | 45 | break; |
f47b72a1 VK |
46 | } |
47 | } | |
48 | ||
b83c1899 VK |
49 | mutex_unlock(&opp_table_lock); |
50 | ||
51 | return managed_table; | |
f47b72a1 VK |
52 | } |
53 | ||
54 | void _of_init_opp_table(struct opp_table *opp_table, struct device *dev) | |
55 | { | |
56 | struct device_node *np; | |
57 | ||
58 | /* | |
59 | * Only required for backward compatibility with v1 bindings, but isn't | |
60 | * harmful for other cases. And so we do it unconditionally. | |
61 | */ | |
62 | np = of_node_get(dev->of_node); | |
63 | if (np) { | |
64 | u32 val; | |
65 | ||
66 | if (!of_property_read_u32(np, "clock-latency", &val)) | |
67 | opp_table->clock_latency_ns_max = val; | |
68 | of_property_read_u32(np, "voltage-tolerance", | |
69 | &opp_table->voltage_tolerance_v1); | |
70 | of_node_put(np); | |
71 | } | |
72 | } | |
73 | ||
74 | static bool _opp_is_supported(struct device *dev, struct opp_table *opp_table, | |
75 | struct device_node *np) | |
76 | { | |
77 | unsigned int count = opp_table->supported_hw_count; | |
78 | u32 version; | |
79 | int ret; | |
80 | ||
a4ee4545 DG |
81 | if (!opp_table->supported_hw) { |
82 | /* | |
83 | * In the case that no supported_hw has been set by the | |
84 | * platform but there is an opp-supported-hw value set for | |
85 | * an OPP then the OPP should not be enabled as there is | |
86 | * no way to see if the hardware supports it. | |
87 | */ | |
88 | if (of_find_property(np, "opp-supported-hw", NULL)) | |
89 | return false; | |
90 | else | |
91 | return true; | |
92 | } | |
f47b72a1 VK |
93 | |
94 | while (count--) { | |
95 | ret = of_property_read_u32_index(np, "opp-supported-hw", count, | |
96 | &version); | |
97 | if (ret) { | |
98 | dev_warn(dev, "%s: failed to read opp-supported-hw property at index %d: %d\n", | |
99 | __func__, count, ret); | |
100 | return false; | |
101 | } | |
102 | ||
103 | /* Both of these are bitwise masks of the versions */ | |
104 | if (!(version & opp_table->supported_hw[count])) | |
105 | return false; | |
106 | } | |
107 | ||
108 | return true; | |
109 | } | |
110 | ||
f47b72a1 VK |
111 | static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev, |
112 | struct opp_table *opp_table) | |
113 | { | |
dfbe4678 VK |
114 | u32 *microvolt, *microamp = NULL; |
115 | int supplies, vcount, icount, ret, i, j; | |
f47b72a1 VK |
116 | struct property *prop = NULL; |
117 | char name[NAME_MAX]; | |
118 | ||
dfbe4678 VK |
119 | supplies = opp_table->regulator_count ? opp_table->regulator_count : 1; |
120 | ||
f47b72a1 VK |
121 | /* Search for "opp-microvolt-<name>" */ |
122 | if (opp_table->prop_name) { | |
123 | snprintf(name, sizeof(name), "opp-microvolt-%s", | |
124 | opp_table->prop_name); | |
125 | prop = of_find_property(opp->np, name, NULL); | |
126 | } | |
127 | ||
128 | if (!prop) { | |
129 | /* Search for "opp-microvolt" */ | |
130 | sprintf(name, "opp-microvolt"); | |
131 | prop = of_find_property(opp->np, name, NULL); | |
132 | ||
133 | /* Missing property isn't a problem, but an invalid entry is */ | |
134 | if (!prop) | |
135 | return 0; | |
136 | } | |
137 | ||
dfbe4678 VK |
138 | vcount = of_property_count_u32_elems(opp->np, name); |
139 | if (vcount < 0) { | |
f47b72a1 | 140 | dev_err(dev, "%s: Invalid %s property (%d)\n", |
dfbe4678 VK |
141 | __func__, name, vcount); |
142 | return vcount; | |
f47b72a1 VK |
143 | } |
144 | ||
dfbe4678 VK |
145 | /* There can be one or three elements per supply */ |
146 | if (vcount != supplies && vcount != supplies * 3) { | |
147 | dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n", | |
148 | __func__, name, vcount, supplies); | |
f47b72a1 VK |
149 | return -EINVAL; |
150 | } | |
151 | ||
dfbe4678 VK |
152 | microvolt = kmalloc_array(vcount, sizeof(*microvolt), GFP_KERNEL); |
153 | if (!microvolt) | |
154 | return -ENOMEM; | |
155 | ||
156 | ret = of_property_read_u32_array(opp->np, name, microvolt, vcount); | |
f47b72a1 VK |
157 | if (ret) { |
158 | dev_err(dev, "%s: error parsing %s: %d\n", __func__, name, ret); | |
dfbe4678 VK |
159 | ret = -EINVAL; |
160 | goto free_microvolt; | |
f47b72a1 VK |
161 | } |
162 | ||
163 | /* Search for "opp-microamp-<name>" */ | |
164 | prop = NULL; | |
165 | if (opp_table->prop_name) { | |
166 | snprintf(name, sizeof(name), "opp-microamp-%s", | |
167 | opp_table->prop_name); | |
168 | prop = of_find_property(opp->np, name, NULL); | |
169 | } | |
170 | ||
171 | if (!prop) { | |
172 | /* Search for "opp-microamp" */ | |
173 | sprintf(name, "opp-microamp"); | |
174 | prop = of_find_property(opp->np, name, NULL); | |
175 | } | |
176 | ||
dfbe4678 VK |
177 | if (prop) { |
178 | icount = of_property_count_u32_elems(opp->np, name); | |
179 | if (icount < 0) { | |
180 | dev_err(dev, "%s: Invalid %s property (%d)\n", __func__, | |
181 | name, icount); | |
182 | ret = icount; | |
183 | goto free_microvolt; | |
184 | } | |
f47b72a1 | 185 | |
dfbe4678 VK |
186 | if (icount != supplies) { |
187 | dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n", | |
188 | __func__, name, icount, supplies); | |
189 | ret = -EINVAL; | |
190 | goto free_microvolt; | |
191 | } | |
192 | ||
193 | microamp = kmalloc_array(icount, sizeof(*microamp), GFP_KERNEL); | |
194 | if (!microamp) { | |
195 | ret = -EINVAL; | |
196 | goto free_microvolt; | |
197 | } | |
198 | ||
199 | ret = of_property_read_u32_array(opp->np, name, microamp, | |
200 | icount); | |
201 | if (ret) { | |
202 | dev_err(dev, "%s: error parsing %s: %d\n", __func__, | |
203 | name, ret); | |
204 | ret = -EINVAL; | |
205 | goto free_microamp; | |
206 | } | |
207 | } | |
208 | ||
209 | for (i = 0, j = 0; i < supplies; i++) { | |
210 | opp->supplies[i].u_volt = microvolt[j++]; | |
211 | ||
212 | if (vcount == supplies) { | |
213 | opp->supplies[i].u_volt_min = opp->supplies[i].u_volt; | |
214 | opp->supplies[i].u_volt_max = opp->supplies[i].u_volt; | |
215 | } else { | |
216 | opp->supplies[i].u_volt_min = microvolt[j++]; | |
217 | opp->supplies[i].u_volt_max = microvolt[j++]; | |
218 | } | |
219 | ||
220 | if (microamp) | |
221 | opp->supplies[i].u_amp = microamp[i]; | |
222 | } | |
223 | ||
224 | free_microamp: | |
225 | kfree(microamp); | |
226 | free_microvolt: | |
227 | kfree(microvolt); | |
228 | ||
229 | return ret; | |
f47b72a1 VK |
230 | } |
231 | ||
232 | /** | |
233 | * dev_pm_opp_of_remove_table() - Free OPP table entries created from static DT | |
234 | * entries | |
235 | * @dev: device pointer used to lookup OPP table. | |
236 | * | |
237 | * Free OPPs created using static entries present in DT. | |
238 | * | |
239 | * Locking: The internal opp_table and opp structures are RCU protected. | |
240 | * Hence this function indirectly uses RCU updater strategy with mutex locks | |
241 | * to keep the integrity of the internal data structures. Callers should ensure | |
242 | * that this function is *NOT* called under RCU protection or in contexts where | |
243 | * mutex cannot be locked. | |
244 | */ | |
245 | void dev_pm_opp_of_remove_table(struct device *dev) | |
246 | { | |
9274c892 | 247 | _dev_pm_opp_find_and_remove_table(dev, false); |
f47b72a1 VK |
248 | } |
249 | EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table); | |
250 | ||
251 | /* Returns opp descriptor node for a device, caller must do of_node_put() */ | |
4bee77dc | 252 | static struct device_node *_of_get_opp_desc_node(struct device *dev) |
f47b72a1 VK |
253 | { |
254 | /* | |
f47b72a1 VK |
255 | * There should be only ONE phandle present in "operating-points-v2" |
256 | * property. | |
257 | */ | |
258 | ||
259 | return of_parse_phandle(dev->of_node, "operating-points-v2", 0); | |
260 | } | |
261 | ||
262 | /** | |
263 | * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings) | |
8cd2f6e8 | 264 | * @opp_table: OPP table |
f47b72a1 VK |
265 | * @dev: device for which we do this operation |
266 | * @np: device node | |
267 | * | |
268 | * This function adds an opp definition to the opp table and returns status. The | |
269 | * opp can be controlled using dev_pm_opp_enable/disable functions and may be | |
270 | * removed by dev_pm_opp_remove. | |
271 | * | |
272 | * Locking: The internal opp_table and opp structures are RCU protected. | |
273 | * Hence this function internally uses RCU updater strategy with mutex locks | |
274 | * to keep the integrity of the internal data structures. Callers should ensure | |
275 | * that this function is *NOT* called under RCU protection or in contexts where | |
276 | * mutex cannot be locked. | |
277 | * | |
278 | * Return: | |
279 | * 0 On success OR | |
280 | * Duplicate OPPs (both freq and volt are same) and opp->available | |
281 | * -EEXIST Freq are same and volt are different OR | |
282 | * Duplicate OPPs (both freq and volt are same) and !opp->available | |
283 | * -ENOMEM Memory allocation failure | |
284 | * -EINVAL Failed parsing the OPP node | |
285 | */ | |
8cd2f6e8 VK |
286 | static int _opp_add_static_v2(struct opp_table *opp_table, struct device *dev, |
287 | struct device_node *np) | |
f47b72a1 | 288 | { |
f47b72a1 VK |
289 | struct dev_pm_opp *new_opp; |
290 | u64 rate; | |
291 | u32 val; | |
292 | int ret; | |
293 | ||
8cd2f6e8 VK |
294 | new_opp = _opp_allocate(opp_table); |
295 | if (!new_opp) | |
296 | return -ENOMEM; | |
f47b72a1 VK |
297 | |
298 | ret = of_property_read_u64(np, "opp-hz", &rate); | |
299 | if (ret < 0) { | |
300 | dev_err(dev, "%s: opp-hz not found\n", __func__); | |
301 | goto free_opp; | |
302 | } | |
303 | ||
304 | /* Check if the OPP supports hardware's hierarchy of versions or not */ | |
305 | if (!_opp_is_supported(dev, opp_table, np)) { | |
306 | dev_dbg(dev, "OPP not supported by hardware: %llu\n", rate); | |
307 | goto free_opp; | |
308 | } | |
309 | ||
310 | /* | |
311 | * Rate is defined as an unsigned long in clk API, and so casting | |
312 | * explicitly to its type. Must be fixed once rate is 64 bit | |
313 | * guaranteed in clk API. | |
314 | */ | |
315 | new_opp->rate = (unsigned long)rate; | |
316 | new_opp->turbo = of_property_read_bool(np, "turbo-mode"); | |
317 | ||
318 | new_opp->np = np; | |
319 | new_opp->dynamic = false; | |
320 | new_opp->available = true; | |
321 | ||
322 | if (!of_property_read_u32(np, "clock-latency-ns", &val)) | |
323 | new_opp->clock_latency_ns = val; | |
324 | ||
325 | ret = opp_parse_supplies(new_opp, dev, opp_table); | |
326 | if (ret) | |
327 | goto free_opp; | |
328 | ||
329 | ret = _opp_add(dev, new_opp, opp_table); | |
7f8538eb VK |
330 | if (ret) { |
331 | /* Don't return error for duplicate OPPs */ | |
332 | if (ret == -EBUSY) | |
333 | ret = 0; | |
f47b72a1 | 334 | goto free_opp; |
7f8538eb | 335 | } |
f47b72a1 VK |
336 | |
337 | /* OPP to select on device suspend */ | |
338 | if (of_property_read_bool(np, "opp-suspend")) { | |
339 | if (opp_table->suspend_opp) { | |
340 | dev_warn(dev, "%s: Multiple suspend OPPs found (%lu %lu)\n", | |
341 | __func__, opp_table->suspend_opp->rate, | |
342 | new_opp->rate); | |
343 | } else { | |
344 | new_opp->suspend = true; | |
345 | opp_table->suspend_opp = new_opp; | |
346 | } | |
347 | } | |
348 | ||
349 | if (new_opp->clock_latency_ns > opp_table->clock_latency_ns_max) | |
350 | opp_table->clock_latency_ns_max = new_opp->clock_latency_ns; | |
351 | ||
f47b72a1 | 352 | pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu\n", |
0f0fe7e0 | 353 | __func__, new_opp->turbo, new_opp->rate, |
dfbe4678 VK |
354 | new_opp->supplies[0].u_volt, new_opp->supplies[0].u_volt_min, |
355 | new_opp->supplies[0].u_volt_max, new_opp->clock_latency_ns); | |
f47b72a1 VK |
356 | |
357 | /* | |
358 | * Notify the changes in the availability of the operable | |
359 | * frequency/voltage list. | |
360 | */ | |
361 | srcu_notifier_call_chain(&opp_table->srcu_head, OPP_EVENT_ADD, new_opp); | |
362 | return 0; | |
363 | ||
364 | free_opp: | |
8cd2f6e8 VK |
365 | _opp_free(new_opp); |
366 | ||
f47b72a1 VK |
367 | return ret; |
368 | } | |
369 | ||
370 | /* Initializes OPP tables based on new bindings */ | |
371 | static int _of_add_opp_table_v2(struct device *dev, struct device_node *opp_np) | |
372 | { | |
373 | struct device_node *np; | |
374 | struct opp_table *opp_table; | |
375 | int ret = 0, count = 0; | |
376 | ||
f47b72a1 VK |
377 | opp_table = _managed_opp(opp_np); |
378 | if (opp_table) { | |
379 | /* OPPs are already managed */ | |
380 | if (!_add_opp_dev(dev, opp_table)) | |
381 | ret = -ENOMEM; | |
b83c1899 | 382 | goto put_opp_table; |
8cd2f6e8 VK |
383 | } |
384 | ||
b83c1899 VK |
385 | opp_table = dev_pm_opp_get_opp_table(dev); |
386 | if (!opp_table) | |
387 | return -ENOMEM; | |
f47b72a1 VK |
388 | |
389 | /* We have opp-table node now, iterate over it and add OPPs */ | |
390 | for_each_available_child_of_node(opp_np, np) { | |
391 | count++; | |
392 | ||
8cd2f6e8 | 393 | ret = _opp_add_static_v2(opp_table, dev, np); |
f47b72a1 VK |
394 | if (ret) { |
395 | dev_err(dev, "%s: Failed to add OPP, %d\n", __func__, | |
396 | ret); | |
b83c1899 VK |
397 | _dev_pm_opp_remove_table(opp_table, dev, false); |
398 | goto put_opp_table; | |
f47b72a1 VK |
399 | } |
400 | } | |
401 | ||
402 | /* There should be one of more OPP defined */ | |
8cd2f6e8 VK |
403 | if (WARN_ON(!count)) { |
404 | ret = -ENOENT; | |
b83c1899 | 405 | goto put_opp_table; |
f47b72a1 VK |
406 | } |
407 | ||
408 | opp_table->np = opp_np; | |
79ee2e8f VK |
409 | if (of_property_read_bool(opp_np, "opp-shared")) |
410 | opp_table->shared_opp = OPP_TABLE_ACCESS_SHARED; | |
411 | else | |
412 | opp_table->shared_opp = OPP_TABLE_ACCESS_EXCLUSIVE; | |
f47b72a1 | 413 | |
b83c1899 VK |
414 | put_opp_table: |
415 | dev_pm_opp_put_opp_table(opp_table); | |
f47b72a1 VK |
416 | |
417 | return ret; | |
418 | } | |
419 | ||
420 | /* Initializes OPP tables based on old-deprecated bindings */ | |
421 | static int _of_add_opp_table_v1(struct device *dev) | |
422 | { | |
8cd2f6e8 | 423 | struct opp_table *opp_table; |
f47b72a1 VK |
424 | const struct property *prop; |
425 | const __be32 *val; | |
8cd2f6e8 | 426 | int nr, ret = 0; |
f47b72a1 VK |
427 | |
428 | prop = of_find_property(dev->of_node, "operating-points", NULL); | |
429 | if (!prop) | |
430 | return -ENODEV; | |
431 | if (!prop->value) | |
432 | return -ENODATA; | |
433 | ||
434 | /* | |
435 | * Each OPP is a set of tuples consisting of frequency and | |
436 | * voltage like <freq-kHz vol-uV>. | |
437 | */ | |
438 | nr = prop->length / sizeof(u32); | |
439 | if (nr % 2) { | |
440 | dev_err(dev, "%s: Invalid OPP table\n", __func__); | |
441 | return -EINVAL; | |
442 | } | |
443 | ||
b83c1899 VK |
444 | opp_table = dev_pm_opp_get_opp_table(dev); |
445 | if (!opp_table) | |
446 | return -ENOMEM; | |
8cd2f6e8 | 447 | |
f47b72a1 VK |
448 | val = prop->value; |
449 | while (nr) { | |
450 | unsigned long freq = be32_to_cpup(val++) * 1000; | |
451 | unsigned long volt = be32_to_cpup(val++); | |
452 | ||
8cd2f6e8 | 453 | ret = _opp_add_v1(opp_table, dev, freq, volt, false); |
04a86a84 VK |
454 | if (ret) { |
455 | dev_err(dev, "%s: Failed to add OPP %ld (%d)\n", | |
456 | __func__, freq, ret); | |
8cd2f6e8 VK |
457 | _dev_pm_opp_remove_table(opp_table, dev, false); |
458 | break; | |
04a86a84 | 459 | } |
f47b72a1 VK |
460 | nr -= 2; |
461 | } | |
462 | ||
b83c1899 | 463 | dev_pm_opp_put_opp_table(opp_table); |
8cd2f6e8 | 464 | return ret; |
f47b72a1 VK |
465 | } |
466 | ||
467 | /** | |
468 | * dev_pm_opp_of_add_table() - Initialize opp table from device tree | |
469 | * @dev: device pointer used to lookup OPP table. | |
470 | * | |
471 | * Register the initial OPP table with the OPP library for given device. | |
472 | * | |
473 | * Locking: The internal opp_table and opp structures are RCU protected. | |
474 | * Hence this function indirectly uses RCU updater strategy with mutex locks | |
475 | * to keep the integrity of the internal data structures. Callers should ensure | |
476 | * that this function is *NOT* called under RCU protection or in contexts where | |
477 | * mutex cannot be locked. | |
478 | * | |
479 | * Return: | |
480 | * 0 On success OR | |
481 | * Duplicate OPPs (both freq and volt are same) and opp->available | |
482 | * -EEXIST Freq are same and volt are different OR | |
483 | * Duplicate OPPs (both freq and volt are same) and !opp->available | |
484 | * -ENOMEM Memory allocation failure | |
485 | * -ENODEV when 'operating-points' property is not found or is invalid data | |
486 | * in device node. | |
487 | * -ENODATA when empty 'operating-points' property is found | |
488 | * -EINVAL when invalid entries are found in opp-v2 table | |
489 | */ | |
490 | int dev_pm_opp_of_add_table(struct device *dev) | |
491 | { | |
492 | struct device_node *opp_np; | |
493 | int ret; | |
494 | ||
495 | /* | |
496 | * OPPs have two version of bindings now. The older one is deprecated, | |
497 | * try for the new binding first. | |
498 | */ | |
499 | opp_np = _of_get_opp_desc_node(dev); | |
500 | if (!opp_np) { | |
501 | /* | |
502 | * Try old-deprecated bindings for backward compatibility with | |
503 | * older dtbs. | |
504 | */ | |
505 | return _of_add_opp_table_v1(dev); | |
506 | } | |
507 | ||
508 | ret = _of_add_opp_table_v2(dev, opp_np); | |
509 | of_node_put(opp_np); | |
510 | ||
511 | return ret; | |
512 | } | |
513 | EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table); | |
514 | ||
515 | /* CPU device specific helpers */ | |
516 | ||
517 | /** | |
518 | * dev_pm_opp_of_cpumask_remove_table() - Removes OPP table for @cpumask | |
519 | * @cpumask: cpumask for which OPP table needs to be removed | |
520 | * | |
521 | * This removes the OPP tables for CPUs present in the @cpumask. | |
522 | * This should be used only to remove static entries created from DT. | |
523 | * | |
524 | * Locking: The internal opp_table and opp structures are RCU protected. | |
525 | * Hence this function internally uses RCU updater strategy with mutex locks | |
526 | * to keep the integrity of the internal data structures. Callers should ensure | |
527 | * that this function is *NOT* called under RCU protection or in contexts where | |
528 | * mutex cannot be locked. | |
529 | */ | |
530 | void dev_pm_opp_of_cpumask_remove_table(const struct cpumask *cpumask) | |
531 | { | |
532 | _dev_pm_opp_cpumask_remove_table(cpumask, true); | |
533 | } | |
534 | EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_remove_table); | |
535 | ||
536 | /** | |
537 | * dev_pm_opp_of_cpumask_add_table() - Adds OPP table for @cpumask | |
538 | * @cpumask: cpumask for which OPP table needs to be added. | |
539 | * | |
540 | * This adds the OPP tables for CPUs present in the @cpumask. | |
541 | * | |
542 | * Locking: The internal opp_table and opp structures are RCU protected. | |
543 | * Hence this function internally uses RCU updater strategy with mutex locks | |
544 | * to keep the integrity of the internal data structures. Callers should ensure | |
545 | * that this function is *NOT* called under RCU protection or in contexts where | |
546 | * mutex cannot be locked. | |
547 | */ | |
548 | int dev_pm_opp_of_cpumask_add_table(const struct cpumask *cpumask) | |
549 | { | |
550 | struct device *cpu_dev; | |
551 | int cpu, ret = 0; | |
552 | ||
553 | WARN_ON(cpumask_empty(cpumask)); | |
554 | ||
555 | for_each_cpu(cpu, cpumask) { | |
556 | cpu_dev = get_cpu_device(cpu); | |
557 | if (!cpu_dev) { | |
558 | pr_err("%s: failed to get cpu%d device\n", __func__, | |
559 | cpu); | |
560 | continue; | |
561 | } | |
562 | ||
563 | ret = dev_pm_opp_of_add_table(cpu_dev); | |
564 | if (ret) { | |
565 | pr_err("%s: couldn't find opp table for cpu:%d, %d\n", | |
566 | __func__, cpu, ret); | |
567 | ||
568 | /* Free all other OPPs */ | |
569 | dev_pm_opp_of_cpumask_remove_table(cpumask); | |
570 | break; | |
571 | } | |
572 | } | |
573 | ||
574 | return ret; | |
575 | } | |
576 | EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_add_table); | |
577 | ||
578 | /* | |
579 | * Works only for OPP v2 bindings. | |
580 | * | |
581 | * Returns -ENOENT if operating-points-v2 bindings aren't supported. | |
582 | */ | |
583 | /** | |
584 | * dev_pm_opp_of_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with | |
585 | * @cpu_dev using operating-points-v2 | |
586 | * bindings. | |
587 | * | |
588 | * @cpu_dev: CPU device for which we do this operation | |
589 | * @cpumask: cpumask to update with information of sharing CPUs | |
590 | * | |
591 | * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev. | |
592 | * | |
593 | * Returns -ENOENT if operating-points-v2 isn't present for @cpu_dev. | |
594 | * | |
595 | * Locking: The internal opp_table and opp structures are RCU protected. | |
596 | * Hence this function internally uses RCU updater strategy with mutex locks | |
597 | * to keep the integrity of the internal data structures. Callers should ensure | |
598 | * that this function is *NOT* called under RCU protection or in contexts where | |
599 | * mutex cannot be locked. | |
600 | */ | |
601 | int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev, | |
602 | struct cpumask *cpumask) | |
603 | { | |
604 | struct device_node *np, *tmp_np; | |
605 | struct device *tcpu_dev; | |
606 | int cpu, ret = 0; | |
607 | ||
608 | /* Get OPP descriptor node */ | |
609 | np = _of_get_opp_desc_node(cpu_dev); | |
610 | if (!np) { | |
349aa92e | 611 | dev_dbg(cpu_dev, "%s: Couldn't find opp node.\n", __func__); |
f47b72a1 VK |
612 | return -ENOENT; |
613 | } | |
614 | ||
615 | cpumask_set_cpu(cpu_dev->id, cpumask); | |
616 | ||
617 | /* OPPs are shared ? */ | |
618 | if (!of_property_read_bool(np, "opp-shared")) | |
619 | goto put_cpu_node; | |
620 | ||
621 | for_each_possible_cpu(cpu) { | |
622 | if (cpu == cpu_dev->id) | |
623 | continue; | |
624 | ||
625 | tcpu_dev = get_cpu_device(cpu); | |
626 | if (!tcpu_dev) { | |
627 | dev_err(cpu_dev, "%s: failed to get cpu%d device\n", | |
628 | __func__, cpu); | |
629 | ret = -ENODEV; | |
630 | goto put_cpu_node; | |
631 | } | |
632 | ||
633 | /* Get OPP descriptor node */ | |
634 | tmp_np = _of_get_opp_desc_node(tcpu_dev); | |
635 | if (!tmp_np) { | |
349aa92e | 636 | dev_err(tcpu_dev, "%s: Couldn't find opp node.\n", |
f47b72a1 VK |
637 | __func__); |
638 | ret = -ENOENT; | |
639 | goto put_cpu_node; | |
640 | } | |
641 | ||
642 | /* CPUs are sharing opp node */ | |
643 | if (np == tmp_np) | |
644 | cpumask_set_cpu(cpu, cpumask); | |
645 | ||
646 | of_node_put(tmp_np); | |
647 | } | |
648 | ||
649 | put_cpu_node: | |
650 | of_node_put(np); | |
651 | return ret; | |
652 | } | |
653 | EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus); |