xref: /linux/drivers/opp/of.c (revision c89756bcf406af313d191cfe3709e7c175c5b0cd)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Generic OPP OF helpers
4  *
5  * Copyright (C) 2009-2010 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/errno.h>
15 #include <linux/device.h>
16 #include <linux/of.h>
17 #include <linux/pm_domain.h>
18 #include <linux/slab.h>
19 #include <linux/export.h>
20 #include <linux/energy_model.h>
21 
22 #include "opp.h"
23 
24 /* OPP tables with uninitialized required OPPs, protected by opp_table_lock */
25 static LIST_HEAD(lazy_opp_tables);
26 
27 /*
28  * Returns opp descriptor node for a device node, caller must
29  * do of_node_put().
30  */
_opp_of_get_opp_desc_node(struct device_node * np,int index)31 static struct device_node *_opp_of_get_opp_desc_node(struct device_node *np,
32 						     int index)
33 {
34 	/* "operating-points-v2" can be an array for power domain providers */
35 	return of_parse_phandle(np, "operating-points-v2", index);
36 }
37 
38 /* Returns opp descriptor node for a device, caller must do of_node_put() */
dev_pm_opp_of_get_opp_desc_node(struct device * dev)39 struct device_node *dev_pm_opp_of_get_opp_desc_node(struct device *dev)
40 {
41 	return _opp_of_get_opp_desc_node(dev->of_node, 0);
42 }
43 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_opp_desc_node);
44 
_managed_opp(struct device * dev,int index)45 struct opp_table *_managed_opp(struct device *dev, int index)
46 {
47 	struct opp_table *opp_table, *managed_table = NULL;
48 	struct device_node *np __free(device_node);
49 
50 	np = _opp_of_get_opp_desc_node(dev->of_node, index);
51 	if (!np)
52 		return NULL;
53 
54 	list_for_each_entry(opp_table, &opp_tables, node) {
55 		if (opp_table->np == np) {
56 			/*
57 			 * Multiple devices can point to the same OPP table and
58 			 * so will have same node-pointer, np.
59 			 *
60 			 * But the OPPs will be considered as shared only if the
61 			 * OPP table contains a "opp-shared" property.
62 			 */
63 			if (opp_table->shared_opp == OPP_TABLE_ACCESS_SHARED)
64 				managed_table = dev_pm_opp_get_opp_table_ref(opp_table);
65 
66 			break;
67 		}
68 	}
69 
70 	return managed_table;
71 }
72 
73 /* The caller must call dev_pm_opp_put() after the OPP is used */
_find_opp_of_np(struct opp_table * opp_table,struct device_node * opp_np)74 static struct dev_pm_opp *_find_opp_of_np(struct opp_table *opp_table,
75 					  struct device_node *opp_np)
76 {
77 	struct dev_pm_opp *opp;
78 
79 	guard(mutex)(&opp_table->lock);
80 
81 	list_for_each_entry(opp, &opp_table->opp_list, node) {
82 		if (opp->np == opp_np)
83 			return dev_pm_opp_get(opp);
84 	}
85 
86 	return NULL;
87 }
88 
of_parse_required_opp(struct device_node * np,int index)89 static struct device_node *of_parse_required_opp(struct device_node *np,
90 						 int index)
91 {
92 	return of_parse_phandle(np, "required-opps", index);
93 }
94 
95 /* The caller must call dev_pm_opp_put_opp_table() after the table is used */
_find_table_of_opp_np(struct device_node * opp_np)96 static struct opp_table *_find_table_of_opp_np(struct device_node *opp_np)
97 {
98 	struct device_node *opp_table_np __free(device_node);
99 	struct opp_table *opp_table;
100 
101 	opp_table_np = of_get_parent(opp_np);
102 	if (!opp_table_np)
103 		return ERR_PTR(-ENODEV);
104 
105 	guard(mutex)(&opp_table_lock);
106 
107 	list_for_each_entry(opp_table, &opp_tables, node) {
108 		if (opp_table_np == opp_table->np)
109 			return dev_pm_opp_get_opp_table_ref(opp_table);
110 	}
111 
112 	return ERR_PTR(-ENODEV);
113 }
114 
115 /* Free resources previously acquired by _opp_table_alloc_required_tables() */
_opp_table_free_required_tables(struct opp_table * opp_table)116 static void _opp_table_free_required_tables(struct opp_table *opp_table)
117 {
118 	struct opp_table **required_opp_tables = opp_table->required_opp_tables;
119 	int i;
120 
121 	if (!required_opp_tables)
122 		return;
123 
124 	for (i = 0; i < opp_table->required_opp_count; i++) {
125 		if (IS_ERR_OR_NULL(required_opp_tables[i]))
126 			continue;
127 
128 		dev_pm_opp_put_opp_table(required_opp_tables[i]);
129 	}
130 
131 	kfree(required_opp_tables);
132 
133 	opp_table->required_opp_count = 0;
134 	opp_table->required_opp_tables = NULL;
135 
136 	guard(mutex)(&opp_table_lock);
137 	list_del(&opp_table->lazy);
138 }
139 
140 /*
141  * Populate all devices and opp tables which are part of "required-opps" list.
142  * Checking only the first OPP node should be enough.
143  */
_opp_table_alloc_required_tables(struct opp_table * opp_table,struct device * dev,struct device_node * opp_np)144 static void _opp_table_alloc_required_tables(struct opp_table *opp_table,
145 					     struct device *dev,
146 					     struct device_node *opp_np)
147 {
148 	struct opp_table **required_opp_tables;
149 	struct device_node *np __free(device_node);
150 	bool lazy = false;
151 	int count, i, size;
152 
153 	/* Traversing the first OPP node is all we need */
154 	np = of_get_next_available_child(opp_np, NULL);
155 	if (!np) {
156 		dev_warn(dev, "Empty OPP table\n");
157 		return;
158 	}
159 
160 	count = of_count_phandle_with_args(np, "required-opps", NULL);
161 	if (count <= 0)
162 		return;
163 
164 	size = sizeof(*required_opp_tables) + sizeof(*opp_table->required_devs);
165 	required_opp_tables = kcalloc(count, size, GFP_KERNEL);
166 	if (!required_opp_tables)
167 		return;
168 
169 	opp_table->required_opp_tables = required_opp_tables;
170 	opp_table->required_devs = (void *)(required_opp_tables + count);
171 	opp_table->required_opp_count = count;
172 
173 	for (i = 0; i < count; i++) {
174 		struct device_node *required_np __free(device_node);
175 
176 		required_np = of_parse_required_opp(np, i);
177 		if (!required_np) {
178 			_opp_table_free_required_tables(opp_table);
179 			return;
180 		}
181 
182 		required_opp_tables[i] = _find_table_of_opp_np(required_np);
183 
184 		if (IS_ERR(required_opp_tables[i]))
185 			lazy = true;
186 	}
187 
188 	/* Let's do the linking later on */
189 	if (lazy) {
190 		/*
191 		 * The OPP table is not held while allocating the table, take it
192 		 * now to avoid corruption to the lazy_opp_tables list.
193 		 */
194 		guard(mutex)(&opp_table_lock);
195 		list_add(&opp_table->lazy, &lazy_opp_tables);
196 	}
197 }
198 
_of_init_opp_table(struct opp_table * opp_table,struct device * dev,int index)199 void _of_init_opp_table(struct opp_table *opp_table, struct device *dev,
200 			int index)
201 {
202 	struct device_node *np __free(device_node), *opp_np;
203 	u32 val;
204 
205 	/*
206 	 * Only required for backward compatibility with v1 bindings, but isn't
207 	 * harmful for other cases. And so we do it unconditionally.
208 	 */
209 	np = of_node_get(dev->of_node);
210 	if (!np)
211 		return;
212 
213 	if (!of_property_read_u32(np, "clock-latency", &val))
214 		opp_table->clock_latency_ns_max = val;
215 	of_property_read_u32(np, "voltage-tolerance",
216 			     &opp_table->voltage_tolerance_v1);
217 
218 	if (of_property_present(np, "#power-domain-cells"))
219 		opp_table->is_genpd = true;
220 
221 	/* Get OPP table node */
222 	opp_np = _opp_of_get_opp_desc_node(np, index);
223 	if (!opp_np)
224 		return;
225 
226 	if (of_property_read_bool(opp_np, "opp-shared"))
227 		opp_table->shared_opp = OPP_TABLE_ACCESS_SHARED;
228 	else
229 		opp_table->shared_opp = OPP_TABLE_ACCESS_EXCLUSIVE;
230 
231 	opp_table->np = opp_np;
232 
233 	_opp_table_alloc_required_tables(opp_table, dev, opp_np);
234 }
235 
_of_clear_opp_table(struct opp_table * opp_table)236 void _of_clear_opp_table(struct opp_table *opp_table)
237 {
238 	_opp_table_free_required_tables(opp_table);
239 	of_node_put(opp_table->np);
240 }
241 
242 /*
243  * Release all resources previously acquired with a call to
244  * _of_opp_alloc_required_opps().
245  */
_of_opp_free_required_opps(struct opp_table * opp_table,struct dev_pm_opp * opp)246 static void _of_opp_free_required_opps(struct opp_table *opp_table,
247 				       struct dev_pm_opp *opp)
248 {
249 	struct dev_pm_opp **required_opps = opp->required_opps;
250 	int i;
251 
252 	if (!required_opps)
253 		return;
254 
255 	for (i = 0; i < opp_table->required_opp_count; i++) {
256 		if (!required_opps[i])
257 			continue;
258 
259 		/* Put the reference back */
260 		dev_pm_opp_put(required_opps[i]);
261 	}
262 
263 	opp->required_opps = NULL;
264 	kfree(required_opps);
265 }
266 
_of_clear_opp(struct opp_table * opp_table,struct dev_pm_opp * opp)267 void _of_clear_opp(struct opp_table *opp_table, struct dev_pm_opp *opp)
268 {
269 	_of_opp_free_required_opps(opp_table, opp);
270 	of_node_put(opp->np);
271 }
272 
_link_required_opps(struct dev_pm_opp * opp,struct opp_table * required_table,int index)273 static int _link_required_opps(struct dev_pm_opp *opp,
274 			       struct opp_table *required_table, int index)
275 {
276 	struct device_node *np __free(device_node);
277 
278 	np = of_parse_required_opp(opp->np, index);
279 	if (unlikely(!np))
280 		return -ENODEV;
281 
282 	opp->required_opps[index] = _find_opp_of_np(required_table, np);
283 	if (!opp->required_opps[index]) {
284 		pr_err("%s: Unable to find required OPP node: %pOF (%d)\n",
285 		       __func__, opp->np, index);
286 		return -ENODEV;
287 	}
288 
289 	return 0;
290 }
291 
292 /* Populate all required OPPs which are part of "required-opps" list */
_of_opp_alloc_required_opps(struct opp_table * opp_table,struct dev_pm_opp * opp)293 static int _of_opp_alloc_required_opps(struct opp_table *opp_table,
294 				       struct dev_pm_opp *opp)
295 {
296 	struct opp_table *required_table;
297 	int i, ret, count = opp_table->required_opp_count;
298 
299 	if (!count)
300 		return 0;
301 
302 	opp->required_opps = kcalloc(count, sizeof(*opp->required_opps), GFP_KERNEL);
303 	if (!opp->required_opps)
304 		return -ENOMEM;
305 
306 	for (i = 0; i < count; i++) {
307 		required_table = opp_table->required_opp_tables[i];
308 
309 		/* Required table not added yet, we will link later */
310 		if (IS_ERR_OR_NULL(required_table))
311 			continue;
312 
313 		ret = _link_required_opps(opp, required_table, i);
314 		if (ret)
315 			goto free_required_opps;
316 	}
317 
318 	return 0;
319 
320 free_required_opps:
321 	_of_opp_free_required_opps(opp_table, opp);
322 
323 	return ret;
324 }
325 
326 /* Link required OPPs for an individual OPP */
lazy_link_required_opps(struct opp_table * opp_table,struct opp_table * new_table,int index)327 static int lazy_link_required_opps(struct opp_table *opp_table,
328 				   struct opp_table *new_table, int index)
329 {
330 	struct dev_pm_opp *opp;
331 	int ret;
332 
333 	list_for_each_entry(opp, &opp_table->opp_list, node) {
334 		ret = _link_required_opps(opp, new_table, index);
335 		if (ret)
336 			return ret;
337 	}
338 
339 	return 0;
340 }
341 
342 /* Link required OPPs for all OPPs of the newly added OPP table */
lazy_link_required_opp_table(struct opp_table * new_table)343 static void lazy_link_required_opp_table(struct opp_table *new_table)
344 {
345 	struct opp_table *opp_table, *temp, **required_opp_tables;
346 	struct dev_pm_opp *opp;
347 	int i, ret;
348 
349 	guard(mutex)(&opp_table_lock);
350 
351 	list_for_each_entry_safe(opp_table, temp, &lazy_opp_tables, lazy) {
352 		struct device_node *opp_np __free(device_node);
353 		bool lazy = false;
354 
355 		/* opp_np can't be invalid here */
356 		opp_np = of_get_next_available_child(opp_table->np, NULL);
357 
358 		for (i = 0; i < opp_table->required_opp_count; i++) {
359 			struct device_node *required_np __free(device_node) = NULL;
360 			struct device_node *required_table_np __free(device_node) = NULL;
361 
362 			required_opp_tables = opp_table->required_opp_tables;
363 
364 			/* Required opp-table is already parsed */
365 			if (!IS_ERR(required_opp_tables[i]))
366 				continue;
367 
368 			/* required_np can't be invalid here */
369 			required_np = of_parse_required_opp(opp_np, i);
370 			required_table_np = of_get_parent(required_np);
371 
372 			/*
373 			 * Newly added table isn't the required opp-table for
374 			 * opp_table.
375 			 */
376 			if (required_table_np != new_table->np) {
377 				lazy = true;
378 				continue;
379 			}
380 
381 			required_opp_tables[i] = dev_pm_opp_get_opp_table_ref(new_table);
382 
383 			/* Link OPPs now */
384 			ret = lazy_link_required_opps(opp_table, new_table, i);
385 			if (ret) {
386 				/* The OPPs will be marked unusable */
387 				lazy = false;
388 				break;
389 			}
390 		}
391 
392 		/* All required opp-tables found, remove from lazy list */
393 		if (!lazy) {
394 			list_del_init(&opp_table->lazy);
395 
396 			list_for_each_entry(opp, &opp_table->opp_list, node)
397 				_required_opps_available(opp, opp_table->required_opp_count);
398 		}
399 	}
400 }
401 
_bandwidth_supported(struct device * dev,struct opp_table * opp_table)402 static int _bandwidth_supported(struct device *dev, struct opp_table *opp_table)
403 {
404 	struct device_node *opp_np __free(device_node) = NULL;
405 	struct device_node *np __free(device_node) = NULL;
406 	struct property *prop;
407 
408 	if (!opp_table) {
409 		struct device_node *np __free(device_node);
410 
411 		np = of_node_get(dev->of_node);
412 		if (!np)
413 			return -ENODEV;
414 
415 		opp_np = _opp_of_get_opp_desc_node(np, 0);
416 	} else {
417 		opp_np = of_node_get(opp_table->np);
418 	}
419 
420 	/* Lets not fail in case we are parsing opp-v1 bindings */
421 	if (!opp_np)
422 		return 0;
423 
424 	/* Checking only first OPP is sufficient */
425 	np = of_get_next_available_child(opp_np, NULL);
426 	if (!np) {
427 		dev_err(dev, "OPP table empty\n");
428 		return -EINVAL;
429 	}
430 
431 	prop = of_find_property(np, "opp-peak-kBps", NULL);
432 	if (!prop || !prop->length)
433 		return 0;
434 
435 	return 1;
436 }
437 
dev_pm_opp_of_find_icc_paths(struct device * dev,struct opp_table * opp_table)438 int dev_pm_opp_of_find_icc_paths(struct device *dev,
439 				 struct opp_table *opp_table)
440 {
441 	struct device_node *np __free(device_node) = of_node_get(dev->of_node);
442 	int ret, i, count, num_paths;
443 	struct icc_path **paths;
444 
445 	ret = _bandwidth_supported(dev, opp_table);
446 	if (ret == -EINVAL)
447 		return 0; /* Empty OPP table is a valid corner-case, let's not fail */
448 	else if (ret <= 0)
449 		return ret;
450 
451 	if (!np)
452 		return 0;
453 
454 	ret = 0;
455 
456 	count = of_count_phandle_with_args(np, "interconnects",
457 					   "#interconnect-cells");
458 	if (count < 0)
459 		return 0;
460 
461 	/* two phandles when #interconnect-cells = <1> */
462 	if (count % 2) {
463 		dev_err(dev, "%s: Invalid interconnects values\n", __func__);
464 		return -EINVAL;
465 	}
466 
467 	num_paths = count / 2;
468 	paths = kcalloc(num_paths, sizeof(*paths), GFP_KERNEL);
469 	if (!paths)
470 		return -ENOMEM;
471 
472 	for (i = 0; i < num_paths; i++) {
473 		paths[i] = of_icc_get_by_index(dev, i);
474 		if (IS_ERR(paths[i])) {
475 			ret = dev_err_probe(dev, PTR_ERR(paths[i]), "%s: Unable to get path%d\n", __func__, i);
476 			goto err;
477 		}
478 	}
479 
480 	if (opp_table) {
481 		opp_table->paths = paths;
482 		opp_table->path_count = num_paths;
483 		return 0;
484 	}
485 
486 err:
487 	while (i--)
488 		icc_put(paths[i]);
489 
490 	kfree(paths);
491 
492 	return ret;
493 }
494 EXPORT_SYMBOL_GPL(dev_pm_opp_of_find_icc_paths);
495 
_opp_is_supported(struct device * dev,struct opp_table * opp_table,struct device_node * np)496 static bool _opp_is_supported(struct device *dev, struct opp_table *opp_table,
497 			      struct device_node *np)
498 {
499 	unsigned int levels = opp_table->supported_hw_count;
500 	int count, versions, ret, i, j;
501 	u32 val;
502 
503 	if (!opp_table->supported_hw) {
504 		/*
505 		 * In the case that no supported_hw has been set by the
506 		 * platform but there is an opp-supported-hw value set for
507 		 * an OPP then the OPP should not be enabled as there is
508 		 * no way to see if the hardware supports it.
509 		 */
510 		if (of_property_present(np, "opp-supported-hw"))
511 			return false;
512 		else
513 			return true;
514 	}
515 
516 	count = of_property_count_u32_elems(np, "opp-supported-hw");
517 	if (count <= 0 || count % levels) {
518 		dev_err(dev, "%s: Invalid opp-supported-hw property (%d)\n",
519 			__func__, count);
520 		return false;
521 	}
522 
523 	versions = count / levels;
524 
525 	/* All levels in at least one of the versions should match */
526 	for (i = 0; i < versions; i++) {
527 		bool supported = true;
528 
529 		for (j = 0; j < levels; j++) {
530 			ret = of_property_read_u32_index(np, "opp-supported-hw",
531 							 i * levels + j, &val);
532 			if (ret) {
533 				dev_warn(dev, "%s: failed to read opp-supported-hw property at index %d: %d\n",
534 					 __func__, i * levels + j, ret);
535 				return false;
536 			}
537 
538 			/* Check if the level is supported */
539 			if (!(val & opp_table->supported_hw[j])) {
540 				supported = false;
541 				break;
542 			}
543 		}
544 
545 		if (supported)
546 			return true;
547 	}
548 
549 	return false;
550 }
551 
_parse_named_prop(struct dev_pm_opp * opp,struct device * dev,struct opp_table * opp_table,const char * prop_type,bool * triplet)552 static u32 *_parse_named_prop(struct dev_pm_opp *opp, struct device *dev,
553 			      struct opp_table *opp_table,
554 			      const char *prop_type, bool *triplet)
555 {
556 	struct property *prop = NULL;
557 	char name[NAME_MAX];
558 	int count, ret;
559 	u32 *out;
560 
561 	/* Search for "opp-<prop_type>-<name>" */
562 	if (opp_table->prop_name) {
563 		snprintf(name, sizeof(name), "opp-%s-%s", prop_type,
564 			 opp_table->prop_name);
565 		prop = of_find_property(opp->np, name, NULL);
566 	}
567 
568 	if (!prop) {
569 		/* Search for "opp-<prop_type>" */
570 		snprintf(name, sizeof(name), "opp-%s", prop_type);
571 		prop = of_find_property(opp->np, name, NULL);
572 		if (!prop)
573 			return NULL;
574 	}
575 
576 	count = of_property_count_u32_elems(opp->np, name);
577 	if (count < 0) {
578 		dev_err(dev, "%s: Invalid %s property (%d)\n", __func__, name,
579 			count);
580 		return ERR_PTR(count);
581 	}
582 
583 	/*
584 	 * Initialize regulator_count, if regulator information isn't provided
585 	 * by the platform. Now that one of the properties is available, fix the
586 	 * regulator_count to 1.
587 	 */
588 	if (unlikely(opp_table->regulator_count == -1))
589 		opp_table->regulator_count = 1;
590 
591 	if (count != opp_table->regulator_count &&
592 	    (!triplet || count != opp_table->regulator_count * 3)) {
593 		dev_err(dev, "%s: Invalid number of elements in %s property (%u) with supplies (%d)\n",
594 			__func__, prop_type, count, opp_table->regulator_count);
595 		return ERR_PTR(-EINVAL);
596 	}
597 
598 	out = kmalloc_array(count, sizeof(*out), GFP_KERNEL);
599 	if (!out)
600 		return ERR_PTR(-EINVAL);
601 
602 	ret = of_property_read_u32_array(opp->np, name, out, count);
603 	if (ret) {
604 		dev_err(dev, "%s: error parsing %s: %d\n", __func__, name, ret);
605 		kfree(out);
606 		return ERR_PTR(-EINVAL);
607 	}
608 
609 	if (triplet)
610 		*triplet = count != opp_table->regulator_count;
611 
612 	return out;
613 }
614 
opp_parse_microvolt(struct dev_pm_opp * opp,struct device * dev,struct opp_table * opp_table,bool * triplet)615 static u32 *opp_parse_microvolt(struct dev_pm_opp *opp, struct device *dev,
616 				struct opp_table *opp_table, bool *triplet)
617 {
618 	u32 *microvolt;
619 
620 	microvolt = _parse_named_prop(opp, dev, opp_table, "microvolt", triplet);
621 	if (IS_ERR(microvolt))
622 		return microvolt;
623 
624 	if (!microvolt) {
625 		/*
626 		 * Missing property isn't a problem, but an invalid
627 		 * entry is. This property isn't optional if regulator
628 		 * information is provided. Check only for the first OPP, as
629 		 * regulator_count may get initialized after that to a valid
630 		 * value.
631 		 */
632 		if (list_empty(&opp_table->opp_list) &&
633 		    opp_table->regulator_count > 0) {
634 			dev_err(dev, "%s: opp-microvolt missing although OPP managing regulators\n",
635 				__func__);
636 			return ERR_PTR(-EINVAL);
637 		}
638 	}
639 
640 	return microvolt;
641 }
642 
opp_parse_supplies(struct dev_pm_opp * opp,struct device * dev,struct opp_table * opp_table)643 static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,
644 			      struct opp_table *opp_table)
645 {
646 	u32 *microvolt, *microamp, *microwatt;
647 	int ret = 0, i, j;
648 	bool triplet;
649 
650 	microvolt = opp_parse_microvolt(opp, dev, opp_table, &triplet);
651 	if (IS_ERR(microvolt))
652 		return PTR_ERR(microvolt);
653 
654 	microamp = _parse_named_prop(opp, dev, opp_table, "microamp", NULL);
655 	if (IS_ERR(microamp)) {
656 		ret = PTR_ERR(microamp);
657 		goto free_microvolt;
658 	}
659 
660 	microwatt = _parse_named_prop(opp, dev, opp_table, "microwatt", NULL);
661 	if (IS_ERR(microwatt)) {
662 		ret = PTR_ERR(microwatt);
663 		goto free_microamp;
664 	}
665 
666 	/*
667 	 * Initialize regulator_count if it is uninitialized and no properties
668 	 * are found.
669 	 */
670 	if (unlikely(opp_table->regulator_count == -1)) {
671 		opp_table->regulator_count = 0;
672 		return 0;
673 	}
674 
675 	for (i = 0, j = 0; i < opp_table->regulator_count; i++) {
676 		if (microvolt) {
677 			opp->supplies[i].u_volt = microvolt[j++];
678 
679 			if (triplet) {
680 				opp->supplies[i].u_volt_min = microvolt[j++];
681 				opp->supplies[i].u_volt_max = microvolt[j++];
682 			} else {
683 				opp->supplies[i].u_volt_min = opp->supplies[i].u_volt;
684 				opp->supplies[i].u_volt_max = opp->supplies[i].u_volt;
685 			}
686 		}
687 
688 		if (microamp)
689 			opp->supplies[i].u_amp = microamp[i];
690 
691 		if (microwatt)
692 			opp->supplies[i].u_watt = microwatt[i];
693 	}
694 
695 	kfree(microwatt);
696 free_microamp:
697 	kfree(microamp);
698 free_microvolt:
699 	kfree(microvolt);
700 
701 	return ret;
702 }
703 
704 /**
705  * dev_pm_opp_of_remove_table() - Free OPP table entries created from static DT
706  *				  entries
707  * @dev:	device pointer used to lookup OPP table.
708  *
709  * Free OPPs created using static entries present in DT.
710  */
dev_pm_opp_of_remove_table(struct device * dev)711 void dev_pm_opp_of_remove_table(struct device *dev)
712 {
713 	dev_pm_opp_remove_table(dev);
714 }
715 EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table);
716 
_read_rate(struct dev_pm_opp * new_opp,struct opp_table * opp_table,struct device_node * np)717 static int _read_rate(struct dev_pm_opp *new_opp, struct opp_table *opp_table,
718 		      struct device_node *np)
719 {
720 	struct property *prop;
721 	int i, count, ret;
722 	u64 *rates;
723 
724 	prop = of_find_property(np, "opp-hz", NULL);
725 	if (!prop)
726 		return -ENODEV;
727 
728 	count = prop->length / sizeof(u64);
729 	if (opp_table->clk_count != count) {
730 		pr_err("%s: Count mismatch between opp-hz and clk_count (%d %d)\n",
731 		       __func__, count, opp_table->clk_count);
732 		return -EINVAL;
733 	}
734 
735 	rates = kmalloc_array(count, sizeof(*rates), GFP_KERNEL);
736 	if (!rates)
737 		return -ENOMEM;
738 
739 	ret = of_property_read_u64_array(np, "opp-hz", rates, count);
740 	if (ret) {
741 		pr_err("%s: Error parsing opp-hz: %d\n", __func__, ret);
742 	} else {
743 		/*
744 		 * Rate is defined as an unsigned long in clk API, and so
745 		 * casting explicitly to its type. Must be fixed once rate is 64
746 		 * bit guaranteed in clk API.
747 		 */
748 		for (i = 0; i < count; i++) {
749 			new_opp->rates[i] = (unsigned long)rates[i];
750 
751 			/* This will happen for frequencies > 4.29 GHz */
752 			WARN_ON(new_opp->rates[i] != rates[i]);
753 		}
754 	}
755 
756 	kfree(rates);
757 
758 	return ret;
759 }
760 
_read_bw(struct dev_pm_opp * new_opp,struct opp_table * opp_table,struct device_node * np,bool peak)761 static int _read_bw(struct dev_pm_opp *new_opp, struct opp_table *opp_table,
762 		    struct device_node *np, bool peak)
763 {
764 	const char *name = peak ? "opp-peak-kBps" : "opp-avg-kBps";
765 	struct property *prop;
766 	int i, count, ret;
767 	u32 *bw;
768 
769 	prop = of_find_property(np, name, NULL);
770 	if (!prop)
771 		return -ENODEV;
772 
773 	count = prop->length / sizeof(u32);
774 	if (opp_table->path_count != count) {
775 		pr_err("%s: Mismatch between %s and paths (%d %d)\n",
776 				__func__, name, count, opp_table->path_count);
777 		return -EINVAL;
778 	}
779 
780 	bw = kmalloc_array(count, sizeof(*bw), GFP_KERNEL);
781 	if (!bw)
782 		return -ENOMEM;
783 
784 	ret = of_property_read_u32_array(np, name, bw, count);
785 	if (ret) {
786 		pr_err("%s: Error parsing %s: %d\n", __func__, name, ret);
787 		goto out;
788 	}
789 
790 	for (i = 0; i < count; i++) {
791 		if (peak)
792 			new_opp->bandwidth[i].peak = kBps_to_icc(bw[i]);
793 		else
794 			new_opp->bandwidth[i].avg = kBps_to_icc(bw[i]);
795 	}
796 
797 out:
798 	kfree(bw);
799 	return ret;
800 }
801 
_read_opp_key(struct dev_pm_opp * new_opp,struct opp_table * opp_table,struct device_node * np)802 static int _read_opp_key(struct dev_pm_opp *new_opp,
803 			 struct opp_table *opp_table, struct device_node *np)
804 {
805 	bool found = false;
806 	int ret;
807 
808 	ret = _read_rate(new_opp, opp_table, np);
809 	if (!ret)
810 		found = true;
811 	else if (ret != -ENODEV)
812 		return ret;
813 
814 	/*
815 	 * Bandwidth consists of peak and average (optional) values:
816 	 * opp-peak-kBps = <path1_value path2_value>;
817 	 * opp-avg-kBps = <path1_value path2_value>;
818 	 */
819 	ret = _read_bw(new_opp, opp_table, np, true);
820 	if (!ret) {
821 		found = true;
822 		ret = _read_bw(new_opp, opp_table, np, false);
823 	}
824 
825 	/* The properties were found but we failed to parse them */
826 	if (ret && ret != -ENODEV)
827 		return ret;
828 
829 	if (!of_property_read_u32(np, "opp-level", &new_opp->level))
830 		found = true;
831 
832 	if (found)
833 		return 0;
834 
835 	return ret;
836 }
837 
838 /**
839  * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings)
840  * @opp_table:	OPP table
841  * @dev:	device for which we do this operation
842  * @np:		device node
843  *
844  * This function adds an opp definition to the opp table and returns status. The
845  * opp can be controlled using dev_pm_opp_enable/disable functions and may be
846  * removed by dev_pm_opp_remove.
847  *
848  * Return:
849  * Valid OPP pointer:
850  *		On success
851  * NULL:
852  *		Duplicate OPPs (both freq and volt are same) and opp->available
853  *		OR if the OPP is not supported by hardware.
854  * ERR_PTR(-EEXIST):
855  *		Freq are same and volt are different OR
856  *		Duplicate OPPs (both freq and volt are same) and !opp->available
857  * ERR_PTR(-ENOMEM):
858  *		Memory allocation failure
859  * ERR_PTR(-EINVAL):
860  *		Failed parsing the OPP node
861  */
_opp_add_static_v2(struct opp_table * opp_table,struct device * dev,struct device_node * np)862 static struct dev_pm_opp *_opp_add_static_v2(struct opp_table *opp_table,
863 		struct device *dev, struct device_node *np)
864 {
865 	struct dev_pm_opp *new_opp;
866 	u32 val;
867 	int ret;
868 
869 	new_opp = _opp_allocate(opp_table);
870 	if (!new_opp)
871 		return ERR_PTR(-ENOMEM);
872 
873 	ret = _read_opp_key(new_opp, opp_table, np);
874 	if (ret < 0) {
875 		dev_err(dev, "%s: opp key field not found\n", __func__);
876 		goto free_opp;
877 	}
878 
879 	/* Check if the OPP supports hardware's hierarchy of versions or not */
880 	if (!_opp_is_supported(dev, opp_table, np)) {
881 		dev_dbg(dev, "OPP not supported by hardware: %s\n",
882 			of_node_full_name(np));
883 		goto free_opp;
884 	}
885 
886 	new_opp->turbo = of_property_read_bool(np, "turbo-mode");
887 
888 	new_opp->np = of_node_get(np);
889 	new_opp->dynamic = false;
890 	new_opp->available = true;
891 
892 	ret = _of_opp_alloc_required_opps(opp_table, new_opp);
893 	if (ret)
894 		goto put_node;
895 
896 	if (!of_property_read_u32(np, "clock-latency-ns", &val))
897 		new_opp->clock_latency_ns = val;
898 
899 	ret = opp_parse_supplies(new_opp, dev, opp_table);
900 	if (ret)
901 		goto free_required_opps;
902 
903 	ret = _opp_add(dev, new_opp, opp_table);
904 	if (ret) {
905 		/* Don't return error for duplicate OPPs */
906 		if (ret == -EBUSY)
907 			ret = 0;
908 		goto free_required_opps;
909 	}
910 
911 	/* OPP to select on device suspend */
912 	if (of_property_read_bool(np, "opp-suspend")) {
913 		if (opp_table->suspend_opp) {
914 			/* Pick the OPP with higher rate/bw/level as suspend OPP */
915 			if (_opp_compare_key(opp_table, new_opp, opp_table->suspend_opp) == 1) {
916 				opp_table->suspend_opp->suspend = false;
917 				new_opp->suspend = true;
918 				opp_table->suspend_opp = new_opp;
919 			}
920 		} else {
921 			new_opp->suspend = true;
922 			opp_table->suspend_opp = new_opp;
923 		}
924 	}
925 
926 	if (new_opp->clock_latency_ns > opp_table->clock_latency_ns_max)
927 		opp_table->clock_latency_ns_max = new_opp->clock_latency_ns;
928 
929 	pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu level:%u\n",
930 		 __func__, new_opp->turbo, new_opp->rates[0],
931 		 new_opp->supplies[0].u_volt, new_opp->supplies[0].u_volt_min,
932 		 new_opp->supplies[0].u_volt_max, new_opp->clock_latency_ns,
933 		 new_opp->level);
934 
935 	/*
936 	 * Notify the changes in the availability of the operable
937 	 * frequency/voltage list.
938 	 */
939 	blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ADD, new_opp);
940 	return new_opp;
941 
942 free_required_opps:
943 	_of_opp_free_required_opps(opp_table, new_opp);
944 put_node:
945 	of_node_put(np);
946 free_opp:
947 	_opp_free(new_opp);
948 
949 	return ret ? ERR_PTR(ret) : NULL;
950 }
951 
952 /* Initializes OPP tables based on new bindings */
_of_add_opp_table_v2(struct device * dev,struct opp_table * opp_table)953 static int _of_add_opp_table_v2(struct device *dev, struct opp_table *opp_table)
954 {
955 	struct device_node *np;
956 	int ret, count = 0;
957 	struct dev_pm_opp *opp;
958 
959 	/* OPP table is already initialized for the device */
960 	scoped_guard(mutex, &opp_table->lock) {
961 		if (opp_table->parsed_static_opps) {
962 			opp_table->parsed_static_opps++;
963 			return 0;
964 		}
965 
966 		opp_table->parsed_static_opps = 1;
967 	}
968 
969 	/* We have opp-table node now, iterate over it and add OPPs */
970 	for_each_available_child_of_node(opp_table->np, np) {
971 		opp = _opp_add_static_v2(opp_table, dev, np);
972 		if (IS_ERR(opp)) {
973 			ret = PTR_ERR(opp);
974 			dev_err(dev, "%s: Failed to add OPP, %d\n", __func__,
975 				ret);
976 			of_node_put(np);
977 			goto remove_static_opp;
978 		} else if (opp) {
979 			count++;
980 		}
981 	}
982 
983 	/* There should be one or more OPPs defined */
984 	if (!count) {
985 		dev_err(dev, "%s: no supported OPPs", __func__);
986 		ret = -ENOENT;
987 		goto remove_static_opp;
988 	}
989 
990 	lazy_link_required_opp_table(opp_table);
991 
992 	return 0;
993 
994 remove_static_opp:
995 	_opp_remove_all_static(opp_table);
996 
997 	return ret;
998 }
999 
1000 /* Initializes OPP tables based on old-deprecated bindings */
_of_add_opp_table_v1(struct device * dev,struct opp_table * opp_table)1001 static int _of_add_opp_table_v1(struct device *dev, struct opp_table *opp_table)
1002 {
1003 	const struct property *prop;
1004 	const __be32 *val;
1005 	int nr, ret = 0;
1006 
1007 	scoped_guard(mutex, &opp_table->lock) {
1008 		if (opp_table->parsed_static_opps) {
1009 			opp_table->parsed_static_opps++;
1010 			return 0;
1011 		}
1012 
1013 		opp_table->parsed_static_opps = 1;
1014 	}
1015 
1016 	prop = of_find_property(dev->of_node, "operating-points", NULL);
1017 	if (!prop) {
1018 		ret = -ENODEV;
1019 		goto remove_static_opp;
1020 	}
1021 	if (!prop->value) {
1022 		ret = -ENODATA;
1023 		goto remove_static_opp;
1024 	}
1025 
1026 	/*
1027 	 * Each OPP is a set of tuples consisting of frequency and
1028 	 * voltage like <freq-kHz vol-uV>.
1029 	 */
1030 	nr = prop->length / sizeof(u32);
1031 	if (nr % 2) {
1032 		dev_err(dev, "%s: Invalid OPP table\n", __func__);
1033 		ret = -EINVAL;
1034 		goto remove_static_opp;
1035 	}
1036 
1037 	val = prop->value;
1038 	while (nr) {
1039 		unsigned long freq = be32_to_cpup(val++) * 1000;
1040 		unsigned long volt = be32_to_cpup(val++);
1041 		struct dev_pm_opp_data data = {
1042 			.freq = freq,
1043 			.u_volt = volt,
1044 		};
1045 
1046 		ret = _opp_add_v1(opp_table, dev, &data, false);
1047 		if (ret) {
1048 			dev_err(dev, "%s: Failed to add OPP %ld (%d)\n",
1049 				__func__, data.freq, ret);
1050 			goto remove_static_opp;
1051 		}
1052 		nr -= 2;
1053 	}
1054 
1055 	return 0;
1056 
1057 remove_static_opp:
1058 	_opp_remove_all_static(opp_table);
1059 
1060 	return ret;
1061 }
1062 
_of_add_table_indexed(struct device * dev,int index)1063 static int _of_add_table_indexed(struct device *dev, int index)
1064 {
1065 	struct opp_table *opp_table;
1066 	int ret, count;
1067 
1068 	if (index) {
1069 		/*
1070 		 * If only one phandle is present, then the same OPP table
1071 		 * applies for all index requests.
1072 		 */
1073 		count = of_count_phandle_with_args(dev->of_node,
1074 						   "operating-points-v2", NULL);
1075 		if (count == 1)
1076 			index = 0;
1077 	}
1078 
1079 	opp_table = _add_opp_table_indexed(dev, index, true);
1080 	if (IS_ERR(opp_table))
1081 		return PTR_ERR(opp_table);
1082 
1083 	/*
1084 	 * OPPs have two version of bindings now. Also try the old (v1)
1085 	 * bindings for backward compatibility with older dtbs.
1086 	 */
1087 	if (opp_table->np)
1088 		ret = _of_add_opp_table_v2(dev, opp_table);
1089 	else
1090 		ret = _of_add_opp_table_v1(dev, opp_table);
1091 
1092 	if (ret)
1093 		dev_pm_opp_put_opp_table(opp_table);
1094 
1095 	return ret;
1096 }
1097 
devm_pm_opp_of_table_release(void * data)1098 static void devm_pm_opp_of_table_release(void *data)
1099 {
1100 	dev_pm_opp_of_remove_table(data);
1101 }
1102 
_devm_of_add_table_indexed(struct device * dev,int index)1103 static int _devm_of_add_table_indexed(struct device *dev, int index)
1104 {
1105 	int ret;
1106 
1107 	ret = _of_add_table_indexed(dev, index);
1108 	if (ret)
1109 		return ret;
1110 
1111 	return devm_add_action_or_reset(dev, devm_pm_opp_of_table_release, dev);
1112 }
1113 
1114 /**
1115  * devm_pm_opp_of_add_table() - Initialize opp table from device tree
1116  * @dev:	device pointer used to lookup OPP table.
1117  *
1118  * Register the initial OPP table with the OPP library for given device.
1119  *
1120  * The opp_table structure will be freed after the device is destroyed.
1121  *
1122  * Return:
1123  * 0		On success OR
1124  *		Duplicate OPPs (both freq and volt are same) and opp->available
1125  * -EEXIST	Freq are same and volt are different OR
1126  *		Duplicate OPPs (both freq and volt are same) and !opp->available
1127  * -ENOMEM	Memory allocation failure
1128  * -ENODEV	when 'operating-points' property is not found or is invalid data
1129  *		in device node.
1130  * -ENODATA	when empty 'operating-points' property is found
1131  * -EINVAL	when invalid entries are found in opp-v2 table
1132  */
devm_pm_opp_of_add_table(struct device * dev)1133 int devm_pm_opp_of_add_table(struct device *dev)
1134 {
1135 	return _devm_of_add_table_indexed(dev, 0);
1136 }
1137 EXPORT_SYMBOL_GPL(devm_pm_opp_of_add_table);
1138 
1139 /**
1140  * dev_pm_opp_of_add_table() - Initialize opp table from device tree
1141  * @dev:	device pointer used to lookup OPP table.
1142  *
1143  * Register the initial OPP table with the OPP library for given device.
1144  *
1145  * Return:
1146  * 0		On success OR
1147  *		Duplicate OPPs (both freq and volt are same) and opp->available
1148  * -EEXIST	Freq are same and volt are different OR
1149  *		Duplicate OPPs (both freq and volt are same) and !opp->available
1150  * -ENOMEM	Memory allocation failure
1151  * -ENODEV	when 'operating-points' property is not found or is invalid data
1152  *		in device node.
1153  * -ENODATA	when empty 'operating-points' property is found
1154  * -EINVAL	when invalid entries are found in opp-v2 table
1155  */
dev_pm_opp_of_add_table(struct device * dev)1156 int dev_pm_opp_of_add_table(struct device *dev)
1157 {
1158 	return _of_add_table_indexed(dev, 0);
1159 }
1160 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table);
1161 
1162 /**
1163  * dev_pm_opp_of_add_table_indexed() - Initialize indexed opp table from device tree
1164  * @dev:	device pointer used to lookup OPP table.
1165  * @index:	Index number.
1166  *
1167  * Register the initial OPP table with the OPP library for given device only
1168  * using the "operating-points-v2" property.
1169  *
1170  * Return: Refer to dev_pm_opp_of_add_table() for return values.
1171  */
dev_pm_opp_of_add_table_indexed(struct device * dev,int index)1172 int dev_pm_opp_of_add_table_indexed(struct device *dev, int index)
1173 {
1174 	return _of_add_table_indexed(dev, index);
1175 }
1176 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table_indexed);
1177 
1178 /**
1179  * devm_pm_opp_of_add_table_indexed() - Initialize indexed opp table from device tree
1180  * @dev:	device pointer used to lookup OPP table.
1181  * @index:	Index number.
1182  *
1183  * This is a resource-managed variant of dev_pm_opp_of_add_table_indexed().
1184  */
devm_pm_opp_of_add_table_indexed(struct device * dev,int index)1185 int devm_pm_opp_of_add_table_indexed(struct device *dev, int index)
1186 {
1187 	return _devm_of_add_table_indexed(dev, index);
1188 }
1189 EXPORT_SYMBOL_GPL(devm_pm_opp_of_add_table_indexed);
1190 
1191 /* CPU device specific helpers */
1192 
1193 /**
1194  * dev_pm_opp_of_cpumask_remove_table() - Removes OPP table for @cpumask
1195  * @cpumask:	cpumask for which OPP table needs to be removed
1196  *
1197  * This removes the OPP tables for CPUs present in the @cpumask.
1198  * This should be used only to remove static entries created from DT.
1199  */
dev_pm_opp_of_cpumask_remove_table(const struct cpumask * cpumask)1200 void dev_pm_opp_of_cpumask_remove_table(const struct cpumask *cpumask)
1201 {
1202 	_dev_pm_opp_cpumask_remove_table(cpumask, -1);
1203 }
1204 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_remove_table);
1205 
1206 /**
1207  * dev_pm_opp_of_cpumask_add_table() - Adds OPP table for @cpumask
1208  * @cpumask:	cpumask for which OPP table needs to be added.
1209  *
1210  * This adds the OPP tables for CPUs present in the @cpumask.
1211  */
dev_pm_opp_of_cpumask_add_table(const struct cpumask * cpumask)1212 int dev_pm_opp_of_cpumask_add_table(const struct cpumask *cpumask)
1213 {
1214 	struct device *cpu_dev;
1215 	int cpu, ret;
1216 
1217 	if (WARN_ON(cpumask_empty(cpumask)))
1218 		return -ENODEV;
1219 
1220 	for_each_cpu(cpu, cpumask) {
1221 		cpu_dev = get_cpu_device(cpu);
1222 		if (!cpu_dev) {
1223 			pr_err("%s: failed to get cpu%d device\n", __func__,
1224 			       cpu);
1225 			ret = -ENODEV;
1226 			goto remove_table;
1227 		}
1228 
1229 		ret = dev_pm_opp_of_add_table(cpu_dev);
1230 		if (ret) {
1231 			/*
1232 			 * OPP may get registered dynamically, don't print error
1233 			 * message here.
1234 			 */
1235 			pr_debug("%s: couldn't find opp table for cpu:%d, %d\n",
1236 				 __func__, cpu, ret);
1237 
1238 			goto remove_table;
1239 		}
1240 	}
1241 
1242 	return 0;
1243 
1244 remove_table:
1245 	/* Free all other OPPs */
1246 	_dev_pm_opp_cpumask_remove_table(cpumask, cpu);
1247 
1248 	return ret;
1249 }
1250 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_add_table);
1251 
1252 /*
1253  * Works only for OPP v2 bindings.
1254  *
1255  * Returns -ENOENT if operating-points-v2 bindings aren't supported.
1256  */
1257 /**
1258  * dev_pm_opp_of_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with
1259  *				      @cpu_dev using operating-points-v2
1260  *				      bindings.
1261  *
1262  * @cpu_dev:	CPU device for which we do this operation
1263  * @cpumask:	cpumask to update with information of sharing CPUs
1264  *
1265  * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev.
1266  *
1267  * Returns -ENOENT if operating-points-v2 isn't present for @cpu_dev.
1268  */
dev_pm_opp_of_get_sharing_cpus(struct device * cpu_dev,struct cpumask * cpumask)1269 int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev,
1270 				   struct cpumask *cpumask)
1271 {
1272 	struct device_node *np __free(device_node);
1273 	int cpu;
1274 
1275 	/* Get OPP descriptor node */
1276 	np = dev_pm_opp_of_get_opp_desc_node(cpu_dev);
1277 	if (!np) {
1278 		dev_dbg(cpu_dev, "%s: Couldn't find opp node.\n", __func__);
1279 		return -ENOENT;
1280 	}
1281 
1282 	cpumask_set_cpu(cpu_dev->id, cpumask);
1283 
1284 	/* OPPs are shared ? */
1285 	if (!of_property_read_bool(np, "opp-shared"))
1286 		return 0;
1287 
1288 	for_each_possible_cpu(cpu) {
1289 		struct device_node *cpu_np __free(device_node) = NULL;
1290 		struct device_node *tmp_np __free(device_node) = NULL;
1291 
1292 		if (cpu == cpu_dev->id)
1293 			continue;
1294 
1295 		cpu_np = of_cpu_device_node_get(cpu);
1296 		if (!cpu_np) {
1297 			dev_err(cpu_dev, "%s: failed to get cpu%d node\n",
1298 				__func__, cpu);
1299 			return -ENOENT;
1300 		}
1301 
1302 		/* Get OPP descriptor node */
1303 		tmp_np = _opp_of_get_opp_desc_node(cpu_np, 0);
1304 		if (!tmp_np) {
1305 			pr_err("%pOF: Couldn't find opp node\n", cpu_np);
1306 			return -ENOENT;
1307 		}
1308 
1309 		/* CPUs are sharing opp node */
1310 		if (np == tmp_np)
1311 			cpumask_set_cpu(cpu, cpumask);
1312 	}
1313 
1314 	return 0;
1315 }
1316 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus);
1317 
1318 /**
1319  * of_get_required_opp_performance_state() - Search for required OPP and return its performance state.
1320  * @np: Node that contains the "required-opps" property.
1321  * @index: Index of the phandle to parse.
1322  *
1323  * Returns the performance state of the OPP pointed out by the "required-opps"
1324  * property at @index in @np.
1325  *
1326  * Return: Zero or positive performance state on success, otherwise negative
1327  * value on errors.
1328  */
of_get_required_opp_performance_state(struct device_node * np,int index)1329 int of_get_required_opp_performance_state(struct device_node *np, int index)
1330 {
1331 	struct device_node *required_np __free(device_node);
1332 	struct opp_table *opp_table __free(put_opp_table) = NULL;
1333 	struct dev_pm_opp *opp __free(put_opp) = NULL;
1334 	int pstate = -EINVAL;
1335 
1336 	required_np = of_parse_required_opp(np, index);
1337 	if (!required_np)
1338 		return -ENODEV;
1339 
1340 	opp_table = _find_table_of_opp_np(required_np);
1341 	if (IS_ERR(opp_table)) {
1342 		pr_err("%s: Failed to find required OPP table %pOF: %ld\n",
1343 		       __func__, np, PTR_ERR(opp_table));
1344 		return PTR_ERR(opp_table);
1345 	}
1346 
1347 	/* The OPP tables must belong to a genpd */
1348 	if (unlikely(!opp_table->is_genpd)) {
1349 		pr_err("%s: Performance state is only valid for genpds.\n", __func__);
1350 		return -EINVAL;
1351 	}
1352 
1353 	opp = _find_opp_of_np(opp_table, required_np);
1354 	if (opp) {
1355 		if (opp->level == OPP_LEVEL_UNSET) {
1356 			pr_err("%s: OPP levels aren't available for %pOF\n",
1357 			       __func__, np);
1358 		} else {
1359 			pstate = opp->level;
1360 		}
1361 	}
1362 
1363 	return pstate;
1364 }
1365 EXPORT_SYMBOL_GPL(of_get_required_opp_performance_state);
1366 
1367 /**
1368  * dev_pm_opp_of_has_required_opp - Find out if a required-opps exists.
1369  * @dev: The device to investigate.
1370  *
1371  * Returns true if the device's node has a "operating-points-v2" property and if
1372  * the corresponding node for the opp-table describes opp nodes that uses the
1373  * "required-opps" property.
1374  *
1375  * Return: True if a required-opps is present, else false.
1376  */
dev_pm_opp_of_has_required_opp(struct device * dev)1377 bool dev_pm_opp_of_has_required_opp(struct device *dev)
1378 {
1379 	struct device_node *np __free(device_node) = NULL, *opp_np __free(device_node);
1380 	int count;
1381 
1382 	opp_np = _opp_of_get_opp_desc_node(dev->of_node, 0);
1383 	if (!opp_np)
1384 		return false;
1385 
1386 	np = of_get_next_available_child(opp_np, NULL);
1387 	if (!np) {
1388 		dev_warn(dev, "Empty OPP table\n");
1389 		return false;
1390 	}
1391 
1392 	count = of_count_phandle_with_args(np, "required-opps", NULL);
1393 
1394 	return count > 0;
1395 }
1396 
1397 /**
1398  * dev_pm_opp_get_of_node() - Gets the DT node corresponding to an opp
1399  * @opp:	opp for which DT node has to be returned for
1400  *
1401  * Return: DT node corresponding to the opp, else 0 on success.
1402  *
1403  * The caller needs to put the node with of_node_put() after using it.
1404  */
dev_pm_opp_get_of_node(struct dev_pm_opp * opp)1405 struct device_node *dev_pm_opp_get_of_node(struct dev_pm_opp *opp)
1406 {
1407 	if (IS_ERR_OR_NULL(opp)) {
1408 		pr_err("%s: Invalid parameters\n", __func__);
1409 		return NULL;
1410 	}
1411 
1412 	return of_node_get(opp->np);
1413 }
1414 EXPORT_SYMBOL_GPL(dev_pm_opp_get_of_node);
1415 
1416 /*
1417  * Callback function provided to the Energy Model framework upon registration.
1418  * It provides the power used by @dev at @kHz if it is the frequency of an
1419  * existing OPP, or at the frequency of the first OPP above @kHz otherwise
1420  * (see dev_pm_opp_find_freq_ceil()). This function updates @kHz to the ceiled
1421  * frequency and @uW to the associated power.
1422  *
1423  * Returns 0 on success or a proper -EINVAL value in case of error.
1424  */
1425 static int __maybe_unused
_get_dt_power(struct device * dev,unsigned long * uW,unsigned long * kHz)1426 _get_dt_power(struct device *dev, unsigned long *uW, unsigned long *kHz)
1427 {
1428 	struct dev_pm_opp *opp __free(put_opp);
1429 	unsigned long opp_freq, opp_power;
1430 
1431 	/* Find the right frequency and related OPP */
1432 	opp_freq = *kHz * 1000;
1433 	opp = dev_pm_opp_find_freq_ceil(dev, &opp_freq);
1434 	if (IS_ERR(opp))
1435 		return -EINVAL;
1436 
1437 	opp_power = dev_pm_opp_get_power(opp);
1438 	if (!opp_power)
1439 		return -EINVAL;
1440 
1441 	*kHz = opp_freq / 1000;
1442 	*uW = opp_power;
1443 
1444 	return 0;
1445 }
1446 
1447 /**
1448  * dev_pm_opp_calc_power() - Calculate power value for device with EM
1449  * @dev		: Device for which an Energy Model has to be registered
1450  * @uW		: New power value that is calculated
1451  * @kHz		: Frequency for which the new power is calculated
1452  *
1453  * This computes the power estimated by @dev at @kHz if it is the frequency
1454  * of an existing OPP, or at the frequency of the first OPP above @kHz otherwise
1455  * (see dev_pm_opp_find_freq_ceil()). This function updates @kHz to the ceiled
1456  * frequency and @uW to the associated power. The power is estimated as
1457  * P = C * V^2 * f with C being the device's capacitance and V and f
1458  * respectively the voltage and frequency of the OPP.
1459  * It is also used as a callback function provided to the Energy Model
1460  * framework upon registration.
1461  *
1462  * Returns -EINVAL if the power calculation failed because of missing
1463  * parameters, 0 otherwise.
1464  */
dev_pm_opp_calc_power(struct device * dev,unsigned long * uW,unsigned long * kHz)1465 int dev_pm_opp_calc_power(struct device *dev, unsigned long *uW,
1466 			  unsigned long *kHz)
1467 {
1468 	struct dev_pm_opp *opp __free(put_opp) = NULL;
1469 	struct device_node *np __free(device_node);
1470 	unsigned long mV, Hz;
1471 	u32 cap;
1472 	u64 tmp;
1473 	int ret;
1474 
1475 	np = of_node_get(dev->of_node);
1476 	if (!np)
1477 		return -EINVAL;
1478 
1479 	ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1480 	if (ret)
1481 		return -EINVAL;
1482 
1483 	Hz = *kHz * 1000;
1484 	opp = dev_pm_opp_find_freq_ceil(dev, &Hz);
1485 	if (IS_ERR(opp))
1486 		return -EINVAL;
1487 
1488 	mV = dev_pm_opp_get_voltage(opp) / 1000;
1489 	if (!mV)
1490 		return -EINVAL;
1491 
1492 	tmp = (u64)cap * mV * mV * (Hz / 1000000);
1493 	/* Provide power in micro-Watts */
1494 	do_div(tmp, 1000000);
1495 
1496 	*uW = (unsigned long)tmp;
1497 	*kHz = Hz / 1000;
1498 
1499 	return 0;
1500 }
1501 EXPORT_SYMBOL_GPL(dev_pm_opp_calc_power);
1502 
_of_has_opp_microwatt_property(struct device * dev)1503 static bool _of_has_opp_microwatt_property(struct device *dev)
1504 {
1505 	struct dev_pm_opp *opp __free(put_opp);
1506 	unsigned long freq = 0;
1507 
1508 	/* Check if at least one OPP has needed property */
1509 	opp = dev_pm_opp_find_freq_ceil(dev, &freq);
1510 	if (IS_ERR(opp))
1511 		return false;
1512 
1513 	return !!dev_pm_opp_get_power(opp);
1514 }
1515 
1516 /**
1517  * dev_pm_opp_of_register_em() - Attempt to register an Energy Model
1518  * @dev		: Device for which an Energy Model has to be registered
1519  * @cpus	: CPUs for which an Energy Model has to be registered. For
1520  *		other type of devices it should be set to NULL.
1521  *
1522  * This checks whether the "dynamic-power-coefficient" devicetree property has
1523  * been specified, and tries to register an Energy Model with it if it has.
1524  * Having this property means the voltages are known for OPPs and the EM
1525  * might be calculated.
1526  */
dev_pm_opp_of_register_em(struct device * dev,struct cpumask * cpus)1527 int dev_pm_opp_of_register_em(struct device *dev, struct cpumask *cpus)
1528 {
1529 	struct device_node *np __free(device_node) = NULL;
1530 	struct em_data_callback em_cb;
1531 	int ret, nr_opp;
1532 	u32 cap;
1533 
1534 	if (IS_ERR_OR_NULL(dev)) {
1535 		ret = -EINVAL;
1536 		goto failed;
1537 	}
1538 
1539 	nr_opp = dev_pm_opp_get_opp_count(dev);
1540 	if (nr_opp <= 0) {
1541 		ret = -EINVAL;
1542 		goto failed;
1543 	}
1544 
1545 	/* First, try to find more precised Energy Model in DT */
1546 	if (_of_has_opp_microwatt_property(dev)) {
1547 		EM_SET_ACTIVE_POWER_CB(em_cb, _get_dt_power);
1548 		goto register_em;
1549 	}
1550 
1551 	np = of_node_get(dev->of_node);
1552 	if (!np) {
1553 		ret = -EINVAL;
1554 		goto failed;
1555 	}
1556 
1557 	/*
1558 	 * Register an EM only if the 'dynamic-power-coefficient' property is
1559 	 * set in devicetree. It is assumed the voltage values are known if that
1560 	 * property is set since it is useless otherwise. If voltages are not
1561 	 * known, just let the EM registration fail with an error to alert the
1562 	 * user about the inconsistent configuration.
1563 	 */
1564 	ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1565 	if (ret || !cap) {
1566 		dev_dbg(dev, "Couldn't find proper 'dynamic-power-coefficient' in DT\n");
1567 		ret = -EINVAL;
1568 		goto failed;
1569 	}
1570 
1571 	EM_SET_ACTIVE_POWER_CB(em_cb, dev_pm_opp_calc_power);
1572 
1573 register_em:
1574 	ret = em_dev_register_perf_domain(dev, nr_opp, &em_cb, cpus, true);
1575 	if (ret)
1576 		goto failed;
1577 
1578 	return 0;
1579 
1580 failed:
1581 	dev_dbg(dev, "Couldn't register Energy Model %d\n", ret);
1582 	return ret;
1583 }
1584 EXPORT_SYMBOL_GPL(dev_pm_opp_of_register_em);
1585