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	*/
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, phandle_name: "operating-points-v2", index);
36	}
37
38	/* Returns opp descriptor node for a device, caller must do of_node_put() */
39	struct device_node *dev_pm_opp_of_get_opp_desc_node(struct device *dev)
40	{
41	return _opp_of_get_opp_desc_node(np: dev->of_node, index: 0);
42	}
43	EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_opp_desc_node);
44
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;
49
50	np = _opp_of_get_opp_desc_node(np: 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	_get_opp_table_kref(opp_table);
65	managed_table = opp_table;
66	}
67
68	break;
69	}
70	}
71
72	of_node_put(node: np);
73
74	return managed_table;
75	}
76
77	/* The caller must call dev_pm_opp_put() after the OPP is used */
78	static struct dev_pm_opp *_find_opp_of_np(struct opp_table *opp_table,
79	struct device_node *opp_np)
80	{
81	struct dev_pm_opp *opp;
82
83	mutex_lock(&opp_table->lock);
84
85	list_for_each_entry(opp, &opp_table->opp_list, node) {
86	if (opp->np == opp_np) {
87	dev_pm_opp_get(opp);
88	mutex_unlock(lock: &opp_table->lock);
89	return opp;
90	}
91	}
92
93	mutex_unlock(lock: &opp_table->lock);
94
95	return NULL;
96	}
97
98	static struct device_node *of_parse_required_opp(struct device_node *np,
99	int index)
100	{
101	return of_parse_phandle(np, phandle_name: "required-opps", index);
102	}
103
104	/* The caller must call dev_pm_opp_put_opp_table() after the table is used */
105	static struct opp_table *_find_table_of_opp_np(struct device_node *opp_np)
106	{
107	struct opp_table *opp_table;
108	struct device_node *opp_table_np;
109
110	opp_table_np = of_get_parent(node: opp_np);
111	if (!opp_table_np)
112	goto err;
113
114	/* It is safe to put the node now as all we need now is its address */
115	of_node_put(node: opp_table_np);
116
117	mutex_lock(&opp_table_lock);
118	list_for_each_entry(opp_table, &opp_tables, node) {
119	if (opp_table_np == opp_table->np) {
120	_get_opp_table_kref(opp_table);
121	mutex_unlock(lock: &opp_table_lock);
122	return opp_table;
123	}
124	}
125	mutex_unlock(lock: &opp_table_lock);
126
127	err:
128	return ERR_PTR(error: -ENODEV);
129	}
130
131	/* Free resources previously acquired by _opp_table_alloc_required_tables() */
132	static void _opp_table_free_required_tables(struct opp_table *opp_table)
133	{
134	struct opp_table **required_opp_tables = opp_table->required_opp_tables;
135	int i;
136
137	if (!required_opp_tables)
138	return;
139
140	for (i = 0; i < opp_table->required_opp_count; i++) {
141	if (IS_ERR_OR_NULL(ptr: required_opp_tables[i]))
142	continue;
143
144	dev_pm_opp_put_opp_table(opp_table: required_opp_tables[i]);
145	}
146
147	kfree(objp: required_opp_tables);
148
149	opp_table->required_opp_count = 0;
150	opp_table->required_opp_tables = NULL;
151
152	mutex_lock(&opp_table_lock);
153	list_del(entry: &opp_table->lazy);
154	mutex_unlock(lock: &opp_table_lock);
155	}
156
157	/*
158	* Populate all devices and opp tables which are part of "required-opps" list.
159	* Checking only the first OPP node should be enough.
160	*/
161	static void _opp_table_alloc_required_tables(struct opp_table *opp_table,
162	struct device *dev,
163	struct device_node *opp_np)
164	{
165	struct opp_table **required_opp_tables;
166	struct device_node *required_np, *np;
167	bool lazy = false;
168	int count, i;
169
170	/* Traversing the first OPP node is all we need */
171	np = of_get_next_available_child(node: opp_np, NULL);
172	if (!np) {
173	dev_warn(dev, "Empty OPP table\n");
174
175	return;
176	}
177
178	count = of_count_phandle_with_args(np, list_name: "required-opps", NULL);
179	if (count <= 0)
180	goto put_np;
181
182	required_opp_tables = kcalloc(n: count, size: sizeof(*required_opp_tables),
183	GFP_KERNEL);
184	if (!required_opp_tables)
185	goto put_np;
186
187	opp_table->required_opp_tables = required_opp_tables;
188	opp_table->required_opp_count = count;
189
190	for (i = 0; i < count; i++) {
191	required_np = of_parse_required_opp(np, index: i);
192	if (!required_np)
193	goto free_required_tables;
194
195	required_opp_tables[i] = _find_table_of_opp_np(opp_np: required_np);
196	of_node_put(node: required_np);
197
198	if (IS_ERR(ptr: required_opp_tables[i]))
199	lazy = true;
200	}
201
202	/* Let's do the linking later on */
203	if (lazy) {
204	/*
205	* The OPP table is not held while allocating the table, take it
206	* now to avoid corruption to the lazy_opp_tables list.
207	*/
208	mutex_lock(&opp_table_lock);
209	list_add(new: &opp_table->lazy, head: &lazy_opp_tables);
210	mutex_unlock(lock: &opp_table_lock);
211	} else {
212	_update_set_required_opps(opp_table);
213	}
214
215	goto put_np;
216
217	free_required_tables:
218	_opp_table_free_required_tables(opp_table);
219	put_np:
220	of_node_put(node: np);
221	}
222
223	void _of_init_opp_table(struct opp_table *opp_table, struct device *dev,
224	int index)
225	{
226	struct device_node *np, *opp_np;
227	u32 val;
228
229	/*
230	* Only required for backward compatibility with v1 bindings, but isn't
231	* harmful for other cases. And so we do it unconditionally.
232	*/
233	np = of_node_get(node: dev->of_node);
234	if (!np)
235	return;
236
237	if (!of_property_read_u32(np, propname: "clock-latency", out_value: &val))
238	opp_table->clock_latency_ns_max = val;
239	of_property_read_u32(np, propname: "voltage-tolerance",
240	out_value: &opp_table->voltage_tolerance_v1);
241
242	if (of_property_present(np, propname: "#power-domain-cells"))
243	opp_table->is_genpd = true;
244
245	/* Get OPP table node */
246	opp_np = _opp_of_get_opp_desc_node(np, index);
247	of_node_put(node: np);
248
249	if (!opp_np)
250	return;
251
252	if (of_property_read_bool(np: opp_np, propname: "opp-shared"))
253	opp_table->shared_opp = OPP_TABLE_ACCESS_SHARED;
254	else
255	opp_table->shared_opp = OPP_TABLE_ACCESS_EXCLUSIVE;
256
257	opp_table->np = opp_np;
258
259	_opp_table_alloc_required_tables(opp_table, dev, opp_np);
260	}
261
262	void _of_clear_opp_table(struct opp_table *opp_table)
263	{
264	_opp_table_free_required_tables(opp_table);
265	of_node_put(node: opp_table->np);
266	}
267
268	/*
269	* Release all resources previously acquired with a call to
270	* _of_opp_alloc_required_opps().
271	*/
272	static void _of_opp_free_required_opps(struct opp_table *opp_table,
273	struct dev_pm_opp *opp)
274	{
275	struct dev_pm_opp **required_opps = opp->required_opps;
276	int i;
277
278	if (!required_opps)
279	return;
280
281	for (i = 0; i < opp_table->required_opp_count; i++) {
282	if (!required_opps[i])
283	continue;
284
285	/* Put the reference back */
286	dev_pm_opp_put(opp: required_opps[i]);
287	}
288
289	opp->required_opps = NULL;
290	kfree(objp: required_opps);
291	}
292
293	void _of_clear_opp(struct opp_table *opp_table, struct dev_pm_opp *opp)
294	{
295	_of_opp_free_required_opps(opp_table, opp);
296	of_node_put(node: opp->np);
297	}
298
299	static int _link_required_opps(struct dev_pm_opp *opp,
300	struct opp_table *required_table, int index)
301	{
302	struct device_node *np;
303
304	np = of_parse_required_opp(np: opp->np, index);
305	if (unlikely(!np))
306	return -ENODEV;
307
308	opp->required_opps[index] = _find_opp_of_np(opp_table: required_table, opp_np: np);
309	of_node_put(node: np);
310
311	if (!opp->required_opps[index]) {
312	pr_err("%s: Unable to find required OPP node: %pOF (%d)\n",
313	__func__, opp->np, index);
314	return -ENODEV;
315	}
316
317	return 0;
318	}
319
320	/* Populate all required OPPs which are part of "required-opps" list */
321	static int _of_opp_alloc_required_opps(struct opp_table *opp_table,
322	struct dev_pm_opp *opp)
323	{
324	struct opp_table *required_table;
325	int i, ret, count = opp_table->required_opp_count;
326
327	if (!count)
328	return 0;
329
330	opp->required_opps = kcalloc(n: count, size: sizeof(*opp->required_opps), GFP_KERNEL);
331	if (!opp->required_opps)
332	return -ENOMEM;
333
334	for (i = 0; i < count; i++) {
335	required_table = opp_table->required_opp_tables[i];
336
337	/* Required table not added yet, we will link later */
338	if (IS_ERR_OR_NULL(ptr: required_table))
339	continue;
340
341	ret = _link_required_opps(opp, required_table, index: i);
342	if (ret)
343	goto free_required_opps;
344	}
345
346	return 0;
347
348	free_required_opps:
349	_of_opp_free_required_opps(opp_table, opp);
350
351	return ret;
352	}
353
354	/* Link required OPPs for an individual OPP */
355	static int lazy_link_required_opps(struct opp_table *opp_table,
356	struct opp_table *new_table, int index)
357	{
358	struct dev_pm_opp *opp;
359	int ret;
360
361	list_for_each_entry(opp, &opp_table->opp_list, node) {
362	ret = _link_required_opps(opp, required_table: new_table, index);
363	if (ret)
364	return ret;
365	}
366
367	return 0;
368	}
369
370	/* Link required OPPs for all OPPs of the newly added OPP table */
371	static void lazy_link_required_opp_table(struct opp_table *new_table)
372	{
373	struct opp_table *opp_table, *temp, **required_opp_tables;
374	struct device_node *required_np, *opp_np, *required_table_np;
375	struct dev_pm_opp *opp;
376	int i, ret;
377
378	mutex_lock(&opp_table_lock);
379
380	list_for_each_entry_safe(opp_table, temp, &lazy_opp_tables, lazy) {
381	bool lazy = false;
382
383	/* opp_np can't be invalid here */
384	opp_np = of_get_next_available_child(node: opp_table->np, NULL);
385
386	for (i = 0; i < opp_table->required_opp_count; i++) {
387	required_opp_tables = opp_table->required_opp_tables;
388
389	/* Required opp-table is already parsed */
390	if (!IS_ERR(ptr: required_opp_tables[i]))
391	continue;
392
393	/* required_np can't be invalid here */
394	required_np = of_parse_required_opp(np: opp_np, index: i);
395	required_table_np = of_get_parent(node: required_np);
396
397	of_node_put(node: required_table_np);
398	of_node_put(node: required_np);
399
400	/*
401	* Newly added table isn't the required opp-table for
402	* opp_table.
403	*/
404	if (required_table_np != new_table->np) {
405	lazy = true;
406	continue;
407	}
408
409	required_opp_tables[i] = new_table;
410	_get_opp_table_kref(opp_table: new_table);
411
412	/* Link OPPs now */
413	ret = lazy_link_required_opps(opp_table, new_table, index: i);
414	if (ret) {
415	/* The OPPs will be marked unusable */
416	lazy = false;
417	break;
418	}
419	}
420
421	of_node_put(node: opp_np);
422
423	/* All required opp-tables found, remove from lazy list */
424	if (!lazy) {
425	_update_set_required_opps(opp_table);
426	list_del_init(entry: &opp_table->lazy);
427
428	list_for_each_entry(opp, &opp_table->opp_list, node)
429	_required_opps_available(opp, count: opp_table->required_opp_count);
430	}
431	}
432
433	mutex_unlock(lock: &opp_table_lock);
434	}
435
436	static int _bandwidth_supported(struct device *dev, struct opp_table *opp_table)
437	{
438	struct device_node *np, *opp_np;
439	struct property *prop;
440
441	if (!opp_table) {
442	np = of_node_get(node: dev->of_node);
443	if (!np)
444	return -ENODEV;
445
446	opp_np = _opp_of_get_opp_desc_node(np, index: 0);
447	of_node_put(node: np);
448	} else {
449	opp_np = of_node_get(node: opp_table->np);
450	}
451
452	/* Lets not fail in case we are parsing opp-v1 bindings */
453	if (!opp_np)
454	return 0;
455
456	/* Checking only first OPP is sufficient */
457	np = of_get_next_available_child(node: opp_np, NULL);
458	of_node_put(node: opp_np);
459	if (!np) {
460	dev_err(dev, "OPP table empty\n");
461	return -EINVAL;
462	}
463
464	prop = of_find_property(np, name: "opp-peak-kBps", NULL);
465	of_node_put(node: np);
466
467	if (!prop || !prop->length)
468	return 0;
469
470	return 1;
471	}
472
473	int dev_pm_opp_of_find_icc_paths(struct device *dev,
474	struct opp_table *opp_table)
475	{
476	struct device_node *np;
477	int ret, i, count, num_paths;
478	struct icc_path **paths;
479
480	ret = _bandwidth_supported(dev, opp_table);
481	if (ret == -EINVAL)
482	return 0; /* Empty OPP table is a valid corner-case, let's not fail */
483	else if (ret <= 0)
484	return ret;
485
486	ret = 0;
487
488	np = of_node_get(node: dev->of_node);
489	if (!np)
490	return 0;
491
492	count = of_count_phandle_with_args(np, list_name: "interconnects",
493	cells_name: "#interconnect-cells");
494	of_node_put(node: np);
495	if (count < 0)
496	return 0;
497
498	/* two phandles when #interconnect-cells = <1> */
499	if (count % 2) {
500	dev_err(dev, "%s: Invalid interconnects values\n", __func__);
501	return -EINVAL;
502	}
503
504	num_paths = count / 2;
505	paths = kcalloc(n: num_paths, size: sizeof(*paths), GFP_KERNEL);
506	if (!paths)
507	return -ENOMEM;
508
509	for (i = 0; i < num_paths; i++) {
510	paths[i] = of_icc_get_by_index(dev, idx: i);
511	if (IS_ERR(ptr: paths[i])) {
512	ret = dev_err_probe(dev, err: PTR_ERR(ptr: paths[i]), fmt: "%s: Unable to get path%d\n", __func__, i);
513	goto err;
514	}
515	}
516
517	if (opp_table) {
518	opp_table->paths = paths;
519	opp_table->path_count = num_paths;
520	return 0;
521	}
522
523	err:
524	while (i--)
525	icc_put(path: paths[i]);
526
527	kfree(objp: paths);
528
529	return ret;
530	}
531	EXPORT_SYMBOL_GPL(dev_pm_opp_of_find_icc_paths);
532
533	static bool _opp_is_supported(struct device *dev, struct opp_table *opp_table,
534	struct device_node *np)
535	{
536	unsigned int levels = opp_table->supported_hw_count;
537	int count, versions, ret, i, j;
538	u32 val;
539
540	if (!opp_table->supported_hw) {
541	/*
542	* In the case that no supported_hw has been set by the
543	* platform but there is an opp-supported-hw value set for
544	* an OPP then the OPP should not be enabled as there is
545	* no way to see if the hardware supports it.
546	*/
547	if (of_property_present(np, propname: "opp-supported-hw"))
548	return false;
549	else
550	return true;
551	}
552
553	count = of_property_count_u32_elems(np, propname: "opp-supported-hw");
554	if (count <= 0 || count % levels) {
555	dev_err(dev, "%s: Invalid opp-supported-hw property (%d)\n",
556	__func__, count);
557	return false;
558	}
559
560	versions = count / levels;
561
562	/* All levels in at least one of the versions should match */
563	for (i = 0; i < versions; i++) {
564	bool supported = true;
565
566	for (j = 0; j < levels; j++) {
567	ret = of_property_read_u32_index(np, propname: "opp-supported-hw",
568	index: i * levels + j, out_value: &val);
569	if (ret) {
570	dev_warn(dev, "%s: failed to read opp-supported-hw property at index %d: %d\n",
571	__func__, i * levels + j, ret);
572	return false;
573	}
574
575	/* Check if the level is supported */
576	if (!(val & opp_table->supported_hw[j])) {
577	supported = false;
578	break;
579	}
580	}
581
582	if (supported)
583	return true;
584	}
585
586	return false;
587	}
588
589	static u32 *_parse_named_prop(struct dev_pm_opp *opp, struct device *dev,
590	struct opp_table *opp_table,
591	const char *prop_type, bool *triplet)
592	{
593	struct property *prop = NULL;
594	char name[NAME_MAX];
595	int count, ret;
596	u32 *out;
597
598	/* Search for "opp-<prop_type>-<name>" */
599	if (opp_table->prop_name) {
600	snprintf(buf: name, size: sizeof(name), fmt: "opp-%s-%s", prop_type,
601	opp_table->prop_name);
602	prop = of_find_property(np: opp->np, name, NULL);
603	}
604
605	if (!prop) {
606	/* Search for "opp-<prop_type>" */
607	snprintf(buf: name, size: sizeof(name), fmt: "opp-%s", prop_type);
608	prop = of_find_property(np: opp->np, name, NULL);
609	if (!prop)
610	return NULL;
611	}
612
613	count = of_property_count_u32_elems(np: opp->np, propname: name);
614	if (count < 0) {
615	dev_err(dev, "%s: Invalid %s property (%d)\n", __func__, name,
616	count);
617	return ERR_PTR(error: count);
618	}
619
620	/*
621	* Initialize regulator_count, if regulator information isn't provided
622	* by the platform. Now that one of the properties is available, fix the
623	* regulator_count to 1.
624	*/
625	if (unlikely(opp_table->regulator_count == -1))
626	opp_table->regulator_count = 1;
627
628	if (count != opp_table->regulator_count &&
629	(!triplet || count != opp_table->regulator_count * 3)) {
630	dev_err(dev, "%s: Invalid number of elements in %s property (%u) with supplies (%d)\n",
631	__func__, prop_type, count, opp_table->regulator_count);
632	return ERR_PTR(error: -EINVAL);
633	}
634
635	out = kmalloc_array(n: count, size: sizeof(*out), GFP_KERNEL);
636	if (!out)
637	return ERR_PTR(error: -EINVAL);
638
639	ret = of_property_read_u32_array(np: opp->np, propname: name, out_values: out, sz: count);
640	if (ret) {
641	dev_err(dev, "%s: error parsing %s: %d\n", __func__, name, ret);
642	kfree(objp: out);
643	return ERR_PTR(error: -EINVAL);
644	}
645
646	if (triplet)
647	*triplet = count != opp_table->regulator_count;
648
649	return out;
650	}
651
652	static u32 *opp_parse_microvolt(struct dev_pm_opp *opp, struct device *dev,
653	struct opp_table *opp_table, bool *triplet)
654	{
655	u32 *microvolt;
656
657	microvolt = _parse_named_prop(opp, dev, opp_table, prop_type: "microvolt", triplet);
658	if (IS_ERR(ptr: microvolt))
659	return microvolt;
660
661	if (!microvolt) {
662	/*
663	* Missing property isn't a problem, but an invalid
664	* entry is. This property isn't optional if regulator
665	* information is provided. Check only for the first OPP, as
666	* regulator_count may get initialized after that to a valid
667	* value.
668	*/
669	if (list_empty(head: &opp_table->opp_list) &&
670	opp_table->regulator_count > 0) {
671	dev_err(dev, "%s: opp-microvolt missing although OPP managing regulators\n",
672	__func__);
673	return ERR_PTR(error: -EINVAL);
674	}
675	}
676
677	return microvolt;
678	}
679
680	static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,
681	struct opp_table *opp_table)
682	{
683	u32 *microvolt, *microamp, *microwatt;
684	int ret = 0, i, j;
685	bool triplet;
686
687	microvolt = opp_parse_microvolt(opp, dev, opp_table, triplet: &triplet);
688	if (IS_ERR(ptr: microvolt))
689	return PTR_ERR(ptr: microvolt);
690
691	microamp = _parse_named_prop(opp, dev, opp_table, prop_type: "microamp", NULL);
692	if (IS_ERR(ptr: microamp)) {
693	ret = PTR_ERR(ptr: microamp);
694	goto free_microvolt;
695	}
696
697	microwatt = _parse_named_prop(opp, dev, opp_table, prop_type: "microwatt", NULL);
698	if (IS_ERR(ptr: microwatt)) {
699	ret = PTR_ERR(ptr: microwatt);
700	goto free_microamp;
701	}
702
703	/*
704	* Initialize regulator_count if it is uninitialized and no properties
705	* are found.
706	*/
707	if (unlikely(opp_table->regulator_count == -1)) {
708	opp_table->regulator_count = 0;
709	return 0;
710	}
711
712	for (i = 0, j = 0; i < opp_table->regulator_count; i++) {
713	if (microvolt) {
714	opp->supplies[i].u_volt = microvolt[j++];
715
716	if (triplet) {
717	opp->supplies[i].u_volt_min = microvolt[j++];
718	opp->supplies[i].u_volt_max = microvolt[j++];
719	} else {
720	opp->supplies[i].u_volt_min = opp->supplies[i].u_volt;
721	opp->supplies[i].u_volt_max = opp->supplies[i].u_volt;
722	}
723	}
724
725	if (microamp)
726	opp->supplies[i].u_amp = microamp[i];
727
728	if (microwatt)
729	opp->supplies[i].u_watt = microwatt[i];
730	}
731
732	kfree(objp: microwatt);
733	free_microamp:
734	kfree(objp: microamp);
735	free_microvolt:
736	kfree(objp: microvolt);
737
738	return ret;
739	}
740
741	/**
742	* dev_pm_opp_of_remove_table() - Free OPP table entries created from static DT
743	* entries
744	* @dev: device pointer used to lookup OPP table.
745	*
746	* Free OPPs created using static entries present in DT.
747	*/
748	void dev_pm_opp_of_remove_table(struct device *dev)
749	{
750	dev_pm_opp_remove_table(dev);
751	}
752	EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table);
753
754	static int _read_rate(struct dev_pm_opp *new_opp, struct opp_table *opp_table,
755	struct device_node *np)
756	{
757	struct property *prop;
758	int i, count, ret;
759	u64 *rates;
760
761	prop = of_find_property(np, name: "opp-hz", NULL);
762	if (!prop)
763	return -ENODEV;
764
765	count = prop->length / sizeof(u64);
766	if (opp_table->clk_count != count) {
767	pr_err("%s: Count mismatch between opp-hz and clk_count (%d %d)\n",
768	__func__, count, opp_table->clk_count);
769	return -EINVAL;
770	}
771
772	rates = kmalloc_array(n: count, size: sizeof(*rates), GFP_KERNEL);
773	if (!rates)
774	return -ENOMEM;
775
776	ret = of_property_read_u64_array(np, propname: "opp-hz", out_values: rates, sz: count);
777	if (ret) {
778	pr_err("%s: Error parsing opp-hz: %d\n", __func__, ret);
779	} else {
780	/*
781	* Rate is defined as an unsigned long in clk API, and so
782	* casting explicitly to its type. Must be fixed once rate is 64
783	* bit guaranteed in clk API.
784	*/
785	for (i = 0; i < count; i++) {
786	new_opp->rates[i] = (unsigned long)rates[i];
787
788	/* This will happen for frequencies > 4.29 GHz */
789	WARN_ON(new_opp->rates[i] != rates[i]);
790	}
791	}
792
793	kfree(objp: rates);
794
795	return ret;
796	}
797
798	static int _read_bw(struct dev_pm_opp *new_opp, struct opp_table *opp_table,
799	struct device_node *np, bool peak)
800	{
801	const char *name = peak ? "opp-peak-kBps" : "opp-avg-kBps";
802	struct property *prop;
803	int i, count, ret;
804	u32 *bw;
805
806	prop = of_find_property(np, name, NULL);
807	if (!prop)
808	return -ENODEV;
809
810	count = prop->length / sizeof(u32);
811	if (opp_table->path_count != count) {
812	pr_err("%s: Mismatch between %s and paths (%d %d)\n",
813	__func__, name, count, opp_table->path_count);
814	return -EINVAL;
815	}
816
817	bw = kmalloc_array(n: count, size: sizeof(*bw), GFP_KERNEL);
818	if (!bw)
819	return -ENOMEM;
820
821	ret = of_property_read_u32_array(np, propname: name, out_values: bw, sz: count);
822	if (ret) {
823	pr_err("%s: Error parsing %s: %d\n", __func__, name, ret);
824	goto out;
825	}
826
827	for (i = 0; i < count; i++) {
828	if (peak)
829	new_opp->bandwidth[i].peak = kBps_to_icc(bw[i]);
830	else
831	new_opp->bandwidth[i].avg = kBps_to_icc(bw[i]);
832	}
833
834	out:
835	kfree(objp: bw);
836	return ret;
837	}
838
839	static int _read_opp_key(struct dev_pm_opp *new_opp,
840	struct opp_table *opp_table, struct device_node *np)
841	{
842	bool found = false;
843	int ret;
844
845	ret = _read_rate(new_opp, opp_table, np);
846	if (!ret)
847	found = true;
848	else if (ret != -ENODEV)
849	return ret;
850
851	/*
852	* Bandwidth consists of peak and average (optional) values:
853	* opp-peak-kBps = <path1_value path2_value>;
854	* opp-avg-kBps = <path1_value path2_value>;
855	*/
856	ret = _read_bw(new_opp, opp_table, np, peak: true);
857	if (!ret) {
858	found = true;
859	ret = _read_bw(new_opp, opp_table, np, peak: false);
860	}
861
862	/* The properties were found but we failed to parse them */
863	if (ret && ret != -ENODEV)
864	return ret;
865
866	if (!of_property_read_u32(np, propname: "opp-level", out_value: &new_opp->level))
867	found = true;
868
869	if (found)
870	return 0;
871
872	return ret;
873	}
874
875	/**
876	* _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings)
877	* @opp_table: OPP table
878	* @dev: device for which we do this operation
879	* @np: device node
880	*
881	* This function adds an opp definition to the opp table and returns status. The
882	* opp can be controlled using dev_pm_opp_enable/disable functions and may be
883	* removed by dev_pm_opp_remove.
884	*
885	* Return:
886	* Valid OPP pointer:
887	* On success
888	* NULL:
889	* Duplicate OPPs (both freq and volt are same) and opp->available
890	* OR if the OPP is not supported by hardware.
891	* ERR_PTR(-EEXIST):
892	* Freq are same and volt are different OR
893	* Duplicate OPPs (both freq and volt are same) and !opp->available
894	* ERR_PTR(-ENOMEM):
895	* Memory allocation failure
896	* ERR_PTR(-EINVAL):
897	* Failed parsing the OPP node
898	*/
899	static struct dev_pm_opp *_opp_add_static_v2(struct opp_table *opp_table,
900	struct device *dev, struct device_node *np)
901	{
902	struct dev_pm_opp *new_opp;
903	u32 val;
904	int ret;
905
906	new_opp = _opp_allocate(opp_table);
907	if (!new_opp)
908	return ERR_PTR(error: -ENOMEM);
909
910	ret = _read_opp_key(new_opp, opp_table, np);
911	if (ret < 0) {
912	dev_err(dev, "%s: opp key field not found\n", __func__);
913	goto free_opp;
914	}
915
916	/* Check if the OPP supports hardware's hierarchy of versions or not */
917	if (!_opp_is_supported(dev, opp_table, np)) {
918	dev_dbg(dev, "OPP not supported by hardware: %s\n",
919	of_node_full_name(np));
920	goto free_opp;
921	}
922
923	new_opp->turbo = of_property_read_bool(np, propname: "turbo-mode");
924
925	new_opp->np = of_node_get(node: np);
926	new_opp->dynamic = false;
927	new_opp->available = true;
928
929	ret = _of_opp_alloc_required_opps(opp_table, opp: new_opp);
930	if (ret)
931	goto free_opp;
932
933	if (!of_property_read_u32(np, propname: "clock-latency-ns", out_value: &val))
934	new_opp->clock_latency_ns = val;
935
936	ret = opp_parse_supplies(opp: new_opp, dev, opp_table);
937	if (ret)
938	goto free_required_opps;
939
940	ret = _opp_add(dev, new_opp, opp_table);
941	if (ret) {
942	/* Don't return error for duplicate OPPs */
943	if (ret == -EBUSY)
944	ret = 0;
945	goto free_required_opps;
946	}
947
948	/* OPP to select on device suspend */
949	if (of_property_read_bool(np, propname: "opp-suspend")) {
950	if (opp_table->suspend_opp) {
951	/* Pick the OPP with higher rate/bw/level as suspend OPP */
952	if (_opp_compare_key(opp_table, opp1: new_opp, opp2: opp_table->suspend_opp) == 1) {
953	opp_table->suspend_opp->suspend = false;
954	new_opp->suspend = true;
955	opp_table->suspend_opp = new_opp;
956	}
957	} else {
958	new_opp->suspend = true;
959	opp_table->suspend_opp = new_opp;
960	}
961	}
962
963	if (new_opp->clock_latency_ns > opp_table->clock_latency_ns_max)
964	opp_table->clock_latency_ns_max = new_opp->clock_latency_ns;
965
966	pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu level:%u\n",
967	__func__, new_opp->turbo, new_opp->rates[0],
968	new_opp->supplies[0].u_volt, new_opp->supplies[0].u_volt_min,
969	new_opp->supplies[0].u_volt_max, new_opp->clock_latency_ns,
970	new_opp->level);
971
972	/*
973	* Notify the changes in the availability of the operable
974	* frequency/voltage list.
975	*/
976	blocking_notifier_call_chain(nh: &opp_table->head, val: OPP_EVENT_ADD, v: new_opp);
977	return new_opp;
978
979	free_required_opps:
980	_of_opp_free_required_opps(opp_table, opp: new_opp);
981	free_opp:
982	_opp_free(opp: new_opp);
983
984	return ret ? ERR_PTR(error: ret) : NULL;
985	}
986
987	/* Initializes OPP tables based on new bindings */
988	static int _of_add_opp_table_v2(struct device *dev, struct opp_table *opp_table)
989	{
990	struct device_node *np;
991	int ret, count = 0;
992	struct dev_pm_opp *opp;
993
994	/* OPP table is already initialized for the device */
995	mutex_lock(&opp_table->lock);
996	if (opp_table->parsed_static_opps) {
997	opp_table->parsed_static_opps++;
998	mutex_unlock(lock: &opp_table->lock);
999	return 0;
1000	}
1001
1002	opp_table->parsed_static_opps = 1;
1003	mutex_unlock(lock: &opp_table->lock);
1004
1005	/* We have opp-table node now, iterate over it and add OPPs */
1006	for_each_available_child_of_node(opp_table->np, np) {
1007	opp = _opp_add_static_v2(opp_table, dev, np);
1008	if (IS_ERR(ptr: opp)) {
1009	ret = PTR_ERR(ptr: opp);
1010	dev_err(dev, "%s: Failed to add OPP, %d\n", __func__,
1011	ret);
1012	of_node_put(node: np);
1013	goto remove_static_opp;
1014	} else if (opp) {
1015	count++;
1016	}
1017	}
1018
1019	/* There should be one or more OPPs defined */
1020	if (!count) {
1021	dev_err(dev, "%s: no supported OPPs", __func__);
1022	ret = -ENOENT;
1023	goto remove_static_opp;
1024	}
1025
1026	lazy_link_required_opp_table(new_table: opp_table);
1027
1028	return 0;
1029
1030	remove_static_opp:
1031	_opp_remove_all_static(opp_table);
1032
1033	return ret;
1034	}
1035
1036	/* Initializes OPP tables based on old-deprecated bindings */
1037	static int _of_add_opp_table_v1(struct device *dev, struct opp_table *opp_table)
1038	{
1039	const struct property *prop;
1040	const __be32 *val;
1041	int nr, ret = 0;
1042
1043	mutex_lock(&opp_table->lock);
1044	if (opp_table->parsed_static_opps) {
1045	opp_table->parsed_static_opps++;
1046	mutex_unlock(lock: &opp_table->lock);
1047	return 0;
1048	}
1049
1050	opp_table->parsed_static_opps = 1;
1051	mutex_unlock(lock: &opp_table->lock);
1052
1053	prop = of_find_property(np: dev->of_node, name: "operating-points", NULL);
1054	if (!prop) {
1055	ret = -ENODEV;
1056	goto remove_static_opp;
1057	}
1058	if (!prop->value) {
1059	ret = -ENODATA;
1060	goto remove_static_opp;
1061	}
1062
1063	/*
1064	* Each OPP is a set of tuples consisting of frequency and
1065	* voltage like <freq-kHz vol-uV>.
1066	*/
1067	nr = prop->length / sizeof(u32);
1068	if (nr % 2) {
1069	dev_err(dev, "%s: Invalid OPP table\n", __func__);
1070	ret = -EINVAL;
1071	goto remove_static_opp;
1072	}
1073
1074	val = prop->value;
1075	while (nr) {
1076	unsigned long freq = be32_to_cpup(p: val++) * 1000;
1077	unsigned long volt = be32_to_cpup(p: val++);
1078	struct dev_pm_opp_data data = {
1079	.freq = freq,
1080	.u_volt = volt,
1081	};
1082
1083	ret = _opp_add_v1(opp_table, dev, data: &data, dynamic: false);
1084	if (ret) {
1085	dev_err(dev, "%s: Failed to add OPP %ld (%d)\n",
1086	__func__, data.freq, ret);
1087	goto remove_static_opp;
1088	}
1089	nr -= 2;
1090	}
1091
1092	return 0;
1093
1094	remove_static_opp:
1095	_opp_remove_all_static(opp_table);
1096
1097	return ret;
1098	}
1099
1100	static int _of_add_table_indexed(struct device *dev, int index)
1101	{
1102	struct opp_table *opp_table;
1103	int ret, count;
1104
1105	if (index) {
1106	/*
1107	* If only one phandle is present, then the same OPP table
1108	* applies for all index requests.
1109	*/
1110	count = of_count_phandle_with_args(np: dev->of_node,
1111	list_name: "operating-points-v2", NULL);
1112	if (count == 1)
1113	index = 0;
1114	}
1115
1116	opp_table = _add_opp_table_indexed(dev, index, getclk: true);
1117	if (IS_ERR(ptr: opp_table))
1118	return PTR_ERR(ptr: opp_table);
1119
1120	/*
1121	* OPPs have two version of bindings now. Also try the old (v1)
1122	* bindings for backward compatibility with older dtbs.
1123	*/
1124	if (opp_table->np)
1125	ret = _of_add_opp_table_v2(dev, opp_table);
1126	else
1127	ret = _of_add_opp_table_v1(dev, opp_table);
1128
1129	if (ret)
1130	dev_pm_opp_put_opp_table(opp_table);
1131
1132	return ret;
1133	}
1134
1135	static void devm_pm_opp_of_table_release(void *data)
1136	{
1137	dev_pm_opp_of_remove_table(data);
1138	}
1139
1140	static int _devm_of_add_table_indexed(struct device *dev, int index)
1141	{
1142	int ret;
1143
1144	ret = _of_add_table_indexed(dev, index);
1145	if (ret)
1146	return ret;
1147
1148	return devm_add_action_or_reset(dev, devm_pm_opp_of_table_release, dev);
1149	}
1150
1151	/**
1152	* devm_pm_opp_of_add_table() - Initialize opp table from device tree
1153	* @dev: device pointer used to lookup OPP table.
1154	*
1155	* Register the initial OPP table with the OPP library for given device.
1156	*
1157	* The opp_table structure will be freed after the device is destroyed.
1158	*
1159	* Return:
1160	* 0 On success OR
1161	* Duplicate OPPs (both freq and volt are same) and opp->available
1162	* -EEXIST Freq are same and volt are different OR
1163	* Duplicate OPPs (both freq and volt are same) and !opp->available
1164	* -ENOMEM Memory allocation failure
1165	* -ENODEV when 'operating-points' property is not found or is invalid data
1166	* in device node.
1167	* -ENODATA when empty 'operating-points' property is found
1168	* -EINVAL when invalid entries are found in opp-v2 table
1169	*/
1170	int devm_pm_opp_of_add_table(struct device *dev)
1171	{
1172	return _devm_of_add_table_indexed(dev, index: 0);
1173	}
1174	EXPORT_SYMBOL_GPL(devm_pm_opp_of_add_table);
1175
1176	/**
1177	* dev_pm_opp_of_add_table() - Initialize opp table from device tree
1178	* @dev: device pointer used to lookup OPP table.
1179	*
1180	* Register the initial OPP table with the OPP library for given device.
1181	*
1182	* Return:
1183	* 0 On success OR
1184	* Duplicate OPPs (both freq and volt are same) and opp->available
1185	* -EEXIST Freq are same and volt are different OR
1186	* Duplicate OPPs (both freq and volt are same) and !opp->available
1187	* -ENOMEM Memory allocation failure
1188	* -ENODEV when 'operating-points' property is not found or is invalid data
1189	* in device node.
1190	* -ENODATA when empty 'operating-points' property is found
1191	* -EINVAL when invalid entries are found in opp-v2 table
1192	*/
1193	int dev_pm_opp_of_add_table(struct device *dev)
1194	{
1195	return _of_add_table_indexed(dev, index: 0);
1196	}
1197	EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table);
1198
1199	/**
1200	* dev_pm_opp_of_add_table_indexed() - Initialize indexed opp table from device tree
1201	* @dev: device pointer used to lookup OPP table.
1202	* @index: Index number.
1203	*
1204	* Register the initial OPP table with the OPP library for given device only
1205	* using the "operating-points-v2" property.
1206	*
1207	* Return: Refer to dev_pm_opp_of_add_table() for return values.
1208	*/
1209	int dev_pm_opp_of_add_table_indexed(struct device *dev, int index)
1210	{
1211	return _of_add_table_indexed(dev, index);
1212	}
1213	EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table_indexed);
1214
1215	/**
1216	* devm_pm_opp_of_add_table_indexed() - Initialize indexed opp table from device tree
1217	* @dev: device pointer used to lookup OPP table.
1218	* @index: Index number.
1219	*
1220	* This is a resource-managed variant of dev_pm_opp_of_add_table_indexed().
1221	*/
1222	int devm_pm_opp_of_add_table_indexed(struct device *dev, int index)
1223	{
1224	return _devm_of_add_table_indexed(dev, index);
1225	}
1226	EXPORT_SYMBOL_GPL(devm_pm_opp_of_add_table_indexed);
1227
1228	/* CPU device specific helpers */
1229
1230	/**
1231	* dev_pm_opp_of_cpumask_remove_table() - Removes OPP table for @cpumask
1232	* @cpumask: cpumask for which OPP table needs to be removed
1233	*
1234	* This removes the OPP tables for CPUs present in the @cpumask.
1235	* This should be used only to remove static entries created from DT.
1236	*/
1237	void dev_pm_opp_of_cpumask_remove_table(const struct cpumask *cpumask)
1238	{
1239	_dev_pm_opp_cpumask_remove_table(cpumask, last_cpu: -1);
1240	}
1241	EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_remove_table);
1242
1243	/**
1244	* dev_pm_opp_of_cpumask_add_table() - Adds OPP table for @cpumask
1245	* @cpumask: cpumask for which OPP table needs to be added.
1246	*
1247	* This adds the OPP tables for CPUs present in the @cpumask.
1248	*/
1249	int dev_pm_opp_of_cpumask_add_table(const struct cpumask *cpumask)
1250	{
1251	struct device *cpu_dev;
1252	int cpu, ret;
1253
1254	if (WARN_ON(cpumask_empty(cpumask)))
1255	return -ENODEV;
1256
1257	for_each_cpu(cpu, cpumask) {
1258	cpu_dev = get_cpu_device(cpu);
1259	if (!cpu_dev) {
1260	pr_err("%s: failed to get cpu%d device\n", __func__,
1261	cpu);
1262	ret = -ENODEV;
1263	goto remove_table;
1264	}
1265
1266	ret = dev_pm_opp_of_add_table(cpu_dev);
1267	if (ret) {
1268	/*
1269	* OPP may get registered dynamically, don't print error
1270	* message here.
1271	*/
1272	pr_debug("%s: couldn't find opp table for cpu:%d, %d\n",
1273	__func__, cpu, ret);
1274
1275	goto remove_table;
1276	}
1277	}
1278
1279	return 0;
1280
1281	remove_table:
1282	/* Free all other OPPs */
1283	_dev_pm_opp_cpumask_remove_table(cpumask, last_cpu: cpu);
1284
1285	return ret;
1286	}
1287	EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_add_table);
1288
1289	/*
1290	* Works only for OPP v2 bindings.
1291	*
1292	* Returns -ENOENT if operating-points-v2 bindings aren't supported.
1293	*/
1294	/**
1295	* dev_pm_opp_of_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with
1296	* @cpu_dev using operating-points-v2
1297	* bindings.
1298	*
1299	* @cpu_dev: CPU device for which we do this operation
1300	* @cpumask: cpumask to update with information of sharing CPUs
1301	*
1302	* This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev.
1303	*
1304	* Returns -ENOENT if operating-points-v2 isn't present for @cpu_dev.
1305	*/
1306	int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev,
1307	struct cpumask *cpumask)
1308	{
1309	struct device_node *np, *tmp_np, *cpu_np;
1310	int cpu, ret = 0;
1311
1312	/* Get OPP descriptor node */
1313	np = dev_pm_opp_of_get_opp_desc_node(cpu_dev);
1314	if (!np) {
1315	dev_dbg(cpu_dev, "%s: Couldn't find opp node.\n", __func__);
1316	return -ENOENT;
1317	}
1318
1319	cpumask_set_cpu(cpu: cpu_dev->id, dstp: cpumask);
1320
1321	/* OPPs are shared ? */
1322	if (!of_property_read_bool(np, propname: "opp-shared"))
1323	goto put_cpu_node;
1324
1325	for_each_possible_cpu(cpu) {
1326	if (cpu == cpu_dev->id)
1327	continue;
1328
1329	cpu_np = of_cpu_device_node_get(cpu);
1330	if (!cpu_np) {
1331	dev_err(cpu_dev, "%s: failed to get cpu%d node\n",
1332	__func__, cpu);
1333	ret = -ENOENT;
1334	goto put_cpu_node;
1335	}
1336
1337	/* Get OPP descriptor node */
1338	tmp_np = _opp_of_get_opp_desc_node(np: cpu_np, index: 0);
1339	of_node_put(node: cpu_np);
1340	if (!tmp_np) {
1341	pr_err("%pOF: Couldn't find opp node\n", cpu_np);
1342	ret = -ENOENT;
1343	goto put_cpu_node;
1344	}
1345
1346	/* CPUs are sharing opp node */
1347	if (np == tmp_np)
1348	cpumask_set_cpu(cpu, dstp: cpumask);
1349
1350	of_node_put(node: tmp_np);
1351	}
1352
1353	put_cpu_node:
1354	of_node_put(node: np);
1355	return ret;
1356	}
1357	EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus);
1358
1359	/**
1360	* of_get_required_opp_performance_state() - Search for required OPP and return its performance state.
1361	* @np: Node that contains the "required-opps" property.
1362	* @index: Index of the phandle to parse.
1363	*
1364	* Returns the performance state of the OPP pointed out by the "required-opps"
1365	* property at @index in @np.
1366	*
1367	* Return: Zero or positive performance state on success, otherwise negative
1368	* value on errors.
1369	*/
1370	int of_get_required_opp_performance_state(struct device_node *np, int index)
1371	{
1372	struct dev_pm_opp *opp;
1373	struct device_node *required_np;
1374	struct opp_table *opp_table;
1375	int pstate = -EINVAL;
1376
1377	required_np = of_parse_required_opp(np, index);
1378	if (!required_np)
1379	return -ENODEV;
1380
1381	opp_table = _find_table_of_opp_np(opp_np: required_np);
1382	if (IS_ERR(ptr: opp_table)) {
1383	pr_err("%s: Failed to find required OPP table %pOF: %ld\n",
1384	__func__, np, PTR_ERR(opp_table));
1385	goto put_required_np;
1386	}
1387
1388	/* The OPP tables must belong to a genpd */
1389	if (unlikely(!opp_table->is_genpd)) {
1390	pr_err("%s: Performance state is only valid for genpds.\n", __func__);
1391	goto put_required_np;
1392	}
1393
1394	opp = _find_opp_of_np(opp_table, opp_np: required_np);
1395	if (opp) {
1396	pstate = opp->level;
1397	dev_pm_opp_put(opp);
1398	}
1399
1400	dev_pm_opp_put_opp_table(opp_table);
1401
1402	put_required_np:
1403	of_node_put(node: required_np);
1404
1405	return pstate;
1406	}
1407	EXPORT_SYMBOL_GPL(of_get_required_opp_performance_state);
1408
1409	/**
1410	* dev_pm_opp_get_of_node() - Gets the DT node corresponding to an opp
1411	* @opp: opp for which DT node has to be returned for
1412	*
1413	* Return: DT node corresponding to the opp, else 0 on success.
1414	*
1415	* The caller needs to put the node with of_node_put() after using it.
1416	*/
1417	struct device_node *dev_pm_opp_get_of_node(struct dev_pm_opp *opp)
1418	{
1419	if (IS_ERR_OR_NULL(ptr: opp)) {
1420	pr_err("%s: Invalid parameters\n", __func__);
1421	return NULL;
1422	}
1423
1424	return of_node_get(node: opp->np);
1425	}
1426	EXPORT_SYMBOL_GPL(dev_pm_opp_get_of_node);
1427
1428	/*
1429	* Callback function provided to the Energy Model framework upon registration.
1430	* It provides the power used by @dev at @kHz if it is the frequency of an
1431	* existing OPP, or at the frequency of the first OPP above @kHz otherwise
1432	* (see dev_pm_opp_find_freq_ceil()). This function updates @kHz to the ceiled
1433	* frequency and @uW to the associated power.
1434	*
1435	* Returns 0 on success or a proper -EINVAL value in case of error.
1436	*/
1437	static int __maybe_unused
1438	_get_dt_power(struct device *dev, unsigned long *uW, unsigned long *kHz)
1439	{
1440	struct dev_pm_opp *opp;
1441	unsigned long opp_freq, opp_power;
1442
1443	/* Find the right frequency and related OPP */
1444	opp_freq = *kHz * 1000;
1445	opp = dev_pm_opp_find_freq_ceil(dev, freq: &opp_freq);
1446	if (IS_ERR(ptr: opp))
1447	return -EINVAL;
1448
1449	opp_power = dev_pm_opp_get_power(opp);
1450	dev_pm_opp_put(opp);
1451	if (!opp_power)
1452	return -EINVAL;
1453
1454	*kHz = opp_freq / 1000;
1455	*uW = opp_power;
1456
1457	return 0;
1458	}
1459
1460	/*
1461	* Callback function provided to the Energy Model framework upon registration.
1462	* This computes the power estimated by @dev at @kHz if it is the frequency
1463	* of an existing OPP, or at the frequency of the first OPP above @kHz otherwise
1464	* (see dev_pm_opp_find_freq_ceil()). This function updates @kHz to the ceiled
1465	* frequency and @uW to the associated power. The power is estimated as
1466	* P = C * V^2 * f with C being the device's capacitance and V and f
1467	* respectively the voltage and frequency of the OPP.
1468	*
1469	* Returns -EINVAL if the power calculation failed because of missing
1470	* parameters, 0 otherwise.
1471	*/
1472	static int __maybe_unused _get_power(struct device *dev, unsigned long *uW,
1473	unsigned long *kHz)
1474	{
1475	struct dev_pm_opp *opp;
1476	struct device_node *np;
1477	unsigned long mV, Hz;
1478	u32 cap;
1479	u64 tmp;
1480	int ret;
1481
1482	np = of_node_get(node: dev->of_node);
1483	if (!np)
1484	return -EINVAL;
1485
1486	ret = of_property_read_u32(np, propname: "dynamic-power-coefficient", out_value: &cap);
1487	of_node_put(node: np);
1488	if (ret)
1489	return -EINVAL;
1490
1491	Hz = *kHz * 1000;
1492	opp = dev_pm_opp_find_freq_ceil(dev, freq: &Hz);
1493	if (IS_ERR(ptr: opp))
1494	return -EINVAL;
1495
1496	mV = dev_pm_opp_get_voltage(opp) / 1000;
1497	dev_pm_opp_put(opp);
1498	if (!mV)
1499	return -EINVAL;
1500
1501	tmp = (u64)cap * mV * mV * (Hz / 1000000);
1502	/* Provide power in micro-Watts */
1503	do_div(tmp, 1000000);
1504
1505	*uW = (unsigned long)tmp;
1506	*kHz = Hz / 1000;
1507
1508	return 0;
1509	}
1510
1511	static bool _of_has_opp_microwatt_property(struct device *dev)
1512	{
1513	unsigned long power, freq = 0;
1514	struct dev_pm_opp *opp;
1515
1516	/* Check if at least one OPP has needed property */
1517	opp = dev_pm_opp_find_freq_ceil(dev, freq: &freq);
1518	if (IS_ERR(ptr: opp))
1519	return false;
1520
1521	power = dev_pm_opp_get_power(opp);
1522	dev_pm_opp_put(opp);
1523	if (!power)
1524	return false;
1525
1526	return true;
1527	}
1528
1529	/**
1530	* dev_pm_opp_of_register_em() - Attempt to register an Energy Model
1531	* @dev : Device for which an Energy Model has to be registered
1532	* @cpus : CPUs for which an Energy Model has to be registered. For
1533	* other type of devices it should be set to NULL.
1534	*
1535	* This checks whether the "dynamic-power-coefficient" devicetree property has
1536	* been specified, and tries to register an Energy Model with it if it has.
1537	* Having this property means the voltages are known for OPPs and the EM
1538	* might be calculated.
1539	*/
1540	int dev_pm_opp_of_register_em(struct device *dev, struct cpumask *cpus)
1541	{
1542	struct em_data_callback em_cb;
1543	struct device_node *np;
1544	int ret, nr_opp;
1545	u32 cap;
1546
1547	if (IS_ERR_OR_NULL(ptr: dev)) {
1548	ret = -EINVAL;
1549	goto failed;
1550	}
1551
1552	nr_opp = dev_pm_opp_get_opp_count(dev);
1553	if (nr_opp <= 0) {
1554	ret = -EINVAL;
1555	goto failed;
1556	}
1557
1558	/* First, try to find more precised Energy Model in DT */
1559	if (_of_has_opp_microwatt_property(dev)) {
1560	EM_SET_ACTIVE_POWER_CB(em_cb, _get_dt_power);
1561	goto register_em;
1562	}
1563
1564	np = of_node_get(node: dev->of_node);
1565	if (!np) {
1566	ret = -EINVAL;
1567	goto failed;
1568	}
1569
1570	/*
1571	* Register an EM only if the 'dynamic-power-coefficient' property is
1572	* set in devicetree. It is assumed the voltage values are known if that
1573	* property is set since it is useless otherwise. If voltages are not
1574	* known, just let the EM registration fail with an error to alert the
1575	* user about the inconsistent configuration.
1576	*/
1577	ret = of_property_read_u32(np, propname: "dynamic-power-coefficient", out_value: &cap);
1578	of_node_put(node: np);
1579	if (ret || !cap) {
1580	dev_dbg(dev, "Couldn't find proper 'dynamic-power-coefficient' in DT\n");
1581	ret = -EINVAL;
1582	goto failed;
1583	}
1584
1585	EM_SET_ACTIVE_POWER_CB(em_cb, _get_power);
1586
1587	register_em:
1588	ret = em_dev_register_perf_domain(dev, nr_states: nr_opp, cb: &em_cb, span: cpus, microwatts: true);
1589	if (ret)
1590	goto failed;
1591
1592	return 0;
1593
1594	failed:
1595	dev_dbg(dev, "Couldn't register Energy Model %d\n", ret);
1596	return ret;
1597	}
1598	EXPORT_SYMBOL_GPL(dev_pm_opp_of_register_em);
1599