Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64...
[platform/kernel/linux-starfive.git] / drivers / opp / of.c
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_device.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 /*
25  * Returns opp descriptor node for a device node, caller must
26  * do of_node_put().
27  */
28 static struct device_node *_opp_of_get_opp_desc_node(struct device_node *np,
29                                                      int index)
30 {
31         /* "operating-points-v2" can be an array for power domain providers */
32         return of_parse_phandle(np, "operating-points-v2", index);
33 }
34
35 /* Returns opp descriptor node for a device, caller must do of_node_put() */
36 struct device_node *dev_pm_opp_of_get_opp_desc_node(struct device *dev)
37 {
38         return _opp_of_get_opp_desc_node(dev->of_node, 0);
39 }
40 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_opp_desc_node);
41
42 struct opp_table *_managed_opp(struct device *dev, int index)
43 {
44         struct opp_table *opp_table, *managed_table = NULL;
45         struct device_node *np;
46
47         np = _opp_of_get_opp_desc_node(dev->of_node, index);
48         if (!np)
49                 return NULL;
50
51         list_for_each_entry(opp_table, &opp_tables, node) {
52                 if (opp_table->np == np) {
53                         /*
54                          * Multiple devices can point to the same OPP table and
55                          * so will have same node-pointer, np.
56                          *
57                          * But the OPPs will be considered as shared only if the
58                          * OPP table contains a "opp-shared" property.
59                          */
60                         if (opp_table->shared_opp == OPP_TABLE_ACCESS_SHARED) {
61                                 _get_opp_table_kref(opp_table);
62                                 managed_table = opp_table;
63                         }
64
65                         break;
66                 }
67         }
68
69         of_node_put(np);
70
71         return managed_table;
72 }
73
74 /* The caller must call dev_pm_opp_put() after the OPP is used */
75 static struct dev_pm_opp *_find_opp_of_np(struct opp_table *opp_table,
76                                           struct device_node *opp_np)
77 {
78         struct dev_pm_opp *opp;
79
80         mutex_lock(&opp_table->lock);
81
82         list_for_each_entry(opp, &opp_table->opp_list, node) {
83                 if (opp->np == opp_np) {
84                         dev_pm_opp_get(opp);
85                         mutex_unlock(&opp_table->lock);
86                         return opp;
87                 }
88         }
89
90         mutex_unlock(&opp_table->lock);
91
92         return NULL;
93 }
94
95 static struct device_node *of_parse_required_opp(struct device_node *np,
96                                                  int index)
97 {
98         struct device_node *required_np;
99
100         required_np = of_parse_phandle(np, "required-opps", index);
101         if (unlikely(!required_np)) {
102                 pr_err("%s: Unable to parse required-opps: %pOF, index: %d\n",
103                        __func__, np, index);
104         }
105
106         return required_np;
107 }
108
109 /* The caller must call dev_pm_opp_put_opp_table() after the table is used */
110 static struct opp_table *_find_table_of_opp_np(struct device_node *opp_np)
111 {
112         struct opp_table *opp_table;
113         struct device_node *opp_table_np;
114
115         lockdep_assert_held(&opp_table_lock);
116
117         opp_table_np = of_get_parent(opp_np);
118         if (!opp_table_np)
119                 goto err;
120
121         /* It is safe to put the node now as all we need now is its address */
122         of_node_put(opp_table_np);
123
124         list_for_each_entry(opp_table, &opp_tables, node) {
125                 if (opp_table_np == opp_table->np) {
126                         _get_opp_table_kref(opp_table);
127                         return opp_table;
128                 }
129         }
130
131 err:
132         return ERR_PTR(-ENODEV);
133 }
134
135 /* Free resources previously acquired by _opp_table_alloc_required_tables() */
136 static void _opp_table_free_required_tables(struct opp_table *opp_table)
137 {
138         struct opp_table **required_opp_tables = opp_table->required_opp_tables;
139         int i;
140
141         if (!required_opp_tables)
142                 return;
143
144         for (i = 0; i < opp_table->required_opp_count; i++) {
145                 if (IS_ERR_OR_NULL(required_opp_tables[i]))
146                         break;
147
148                 dev_pm_opp_put_opp_table(required_opp_tables[i]);
149         }
150
151         kfree(required_opp_tables);
152
153         opp_table->required_opp_count = 0;
154         opp_table->required_opp_tables = NULL;
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         int count, i;
168
169         /* Traversing the first OPP node is all we need */
170         np = of_get_next_available_child(opp_np, NULL);
171         if (!np) {
172                 dev_err(dev, "Empty OPP table\n");
173                 return;
174         }
175
176         count = of_count_phandle_with_args(np, "required-opps", NULL);
177         if (!count)
178                 goto put_np;
179
180         required_opp_tables = kcalloc(count, sizeof(*required_opp_tables),
181                                       GFP_KERNEL);
182         if (!required_opp_tables)
183                 goto put_np;
184
185         opp_table->required_opp_tables = required_opp_tables;
186         opp_table->required_opp_count = count;
187
188         for (i = 0; i < count; i++) {
189                 required_np = of_parse_required_opp(np, i);
190                 if (!required_np)
191                         goto free_required_tables;
192
193                 required_opp_tables[i] = _find_table_of_opp_np(required_np);
194                 of_node_put(required_np);
195
196                 if (IS_ERR(required_opp_tables[i]))
197                         goto free_required_tables;
198
199                 /*
200                  * We only support genpd's OPPs in the "required-opps" for now,
201                  * as we don't know how much about other cases. Error out if the
202                  * required OPP doesn't belong to a genpd.
203                  */
204                 if (!required_opp_tables[i]->is_genpd) {
205                         dev_err(dev, "required-opp doesn't belong to genpd: %pOF\n",
206                                 required_np);
207                         goto free_required_tables;
208                 }
209         }
210
211         goto put_np;
212
213 free_required_tables:
214         _opp_table_free_required_tables(opp_table);
215 put_np:
216         of_node_put(np);
217 }
218
219 void _of_init_opp_table(struct opp_table *opp_table, struct device *dev,
220                         int index)
221 {
222         struct device_node *np, *opp_np;
223         u32 val;
224
225         /*
226          * Only required for backward compatibility with v1 bindings, but isn't
227          * harmful for other cases. And so we do it unconditionally.
228          */
229         np = of_node_get(dev->of_node);
230         if (!np)
231                 return;
232
233         if (!of_property_read_u32(np, "clock-latency", &val))
234                 opp_table->clock_latency_ns_max = val;
235         of_property_read_u32(np, "voltage-tolerance",
236                              &opp_table->voltage_tolerance_v1);
237
238         if (of_find_property(np, "#power-domain-cells", NULL))
239                 opp_table->is_genpd = true;
240
241         /* Get OPP table node */
242         opp_np = _opp_of_get_opp_desc_node(np, index);
243         of_node_put(np);
244
245         if (!opp_np)
246                 return;
247
248         if (of_property_read_bool(opp_np, "opp-shared"))
249                 opp_table->shared_opp = OPP_TABLE_ACCESS_SHARED;
250         else
251                 opp_table->shared_opp = OPP_TABLE_ACCESS_EXCLUSIVE;
252
253         opp_table->np = opp_np;
254
255         _opp_table_alloc_required_tables(opp_table, dev, opp_np);
256         of_node_put(opp_np);
257 }
258
259 void _of_clear_opp_table(struct opp_table *opp_table)
260 {
261         _opp_table_free_required_tables(opp_table);
262 }
263
264 /*
265  * Release all resources previously acquired with a call to
266  * _of_opp_alloc_required_opps().
267  */
268 void _of_opp_free_required_opps(struct opp_table *opp_table,
269                                 struct dev_pm_opp *opp)
270 {
271         struct dev_pm_opp **required_opps = opp->required_opps;
272         int i;
273
274         if (!required_opps)
275                 return;
276
277         for (i = 0; i < opp_table->required_opp_count; i++) {
278                 if (!required_opps[i])
279                         break;
280
281                 /* Put the reference back */
282                 dev_pm_opp_put(required_opps[i]);
283         }
284
285         kfree(required_opps);
286         opp->required_opps = NULL;
287 }
288
289 /* Populate all required OPPs which are part of "required-opps" list */
290 static int _of_opp_alloc_required_opps(struct opp_table *opp_table,
291                                        struct dev_pm_opp *opp)
292 {
293         struct dev_pm_opp **required_opps;
294         struct opp_table *required_table;
295         struct device_node *np;
296         int i, ret, count = opp_table->required_opp_count;
297
298         if (!count)
299                 return 0;
300
301         required_opps = kcalloc(count, sizeof(*required_opps), GFP_KERNEL);
302         if (!required_opps)
303                 return -ENOMEM;
304
305         opp->required_opps = required_opps;
306
307         for (i = 0; i < count; i++) {
308                 required_table = opp_table->required_opp_tables[i];
309
310                 np = of_parse_required_opp(opp->np, i);
311                 if (unlikely(!np)) {
312                         ret = -ENODEV;
313                         goto free_required_opps;
314                 }
315
316                 required_opps[i] = _find_opp_of_np(required_table, np);
317                 of_node_put(np);
318
319                 if (!required_opps[i]) {
320                         pr_err("%s: Unable to find required OPP node: %pOF (%d)\n",
321                                __func__, opp->np, i);
322                         ret = -ENODEV;
323                         goto free_required_opps;
324                 }
325         }
326
327         return 0;
328
329 free_required_opps:
330         _of_opp_free_required_opps(opp_table, opp);
331
332         return ret;
333 }
334
335 static bool _opp_is_supported(struct device *dev, struct opp_table *opp_table,
336                               struct device_node *np)
337 {
338         unsigned int count = opp_table->supported_hw_count;
339         u32 version;
340         int ret;
341
342         if (!opp_table->supported_hw) {
343                 /*
344                  * In the case that no supported_hw has been set by the
345                  * platform but there is an opp-supported-hw value set for
346                  * an OPP then the OPP should not be enabled as there is
347                  * no way to see if the hardware supports it.
348                  */
349                 if (of_find_property(np, "opp-supported-hw", NULL))
350                         return false;
351                 else
352                         return true;
353         }
354
355         while (count--) {
356                 ret = of_property_read_u32_index(np, "opp-supported-hw", count,
357                                                  &version);
358                 if (ret) {
359                         dev_warn(dev, "%s: failed to read opp-supported-hw property at index %d: %d\n",
360                                  __func__, count, ret);
361                         return false;
362                 }
363
364                 /* Both of these are bitwise masks of the versions */
365                 if (!(version & opp_table->supported_hw[count]))
366                         return false;
367         }
368
369         return true;
370 }
371
372 static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,
373                               struct opp_table *opp_table)
374 {
375         u32 *microvolt, *microamp = NULL;
376         int supplies = opp_table->regulator_count, vcount, icount, ret, i, j;
377         struct property *prop = NULL;
378         char name[NAME_MAX];
379
380         /* Search for "opp-microvolt-<name>" */
381         if (opp_table->prop_name) {
382                 snprintf(name, sizeof(name), "opp-microvolt-%s",
383                          opp_table->prop_name);
384                 prop = of_find_property(opp->np, name, NULL);
385         }
386
387         if (!prop) {
388                 /* Search for "opp-microvolt" */
389                 sprintf(name, "opp-microvolt");
390                 prop = of_find_property(opp->np, name, NULL);
391
392                 /* Missing property isn't a problem, but an invalid entry is */
393                 if (!prop) {
394                         if (unlikely(supplies == -1)) {
395                                 /* Initialize regulator_count */
396                                 opp_table->regulator_count = 0;
397                                 return 0;
398                         }
399
400                         if (!supplies)
401                                 return 0;
402
403                         dev_err(dev, "%s: opp-microvolt missing although OPP managing regulators\n",
404                                 __func__);
405                         return -EINVAL;
406                 }
407         }
408
409         if (unlikely(supplies == -1)) {
410                 /* Initialize regulator_count */
411                 supplies = opp_table->regulator_count = 1;
412         } else if (unlikely(!supplies)) {
413                 dev_err(dev, "%s: opp-microvolt wasn't expected\n", __func__);
414                 return -EINVAL;
415         }
416
417         vcount = of_property_count_u32_elems(opp->np, name);
418         if (vcount < 0) {
419                 dev_err(dev, "%s: Invalid %s property (%d)\n",
420                         __func__, name, vcount);
421                 return vcount;
422         }
423
424         /* There can be one or three elements per supply */
425         if (vcount != supplies && vcount != supplies * 3) {
426                 dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
427                         __func__, name, vcount, supplies);
428                 return -EINVAL;
429         }
430
431         microvolt = kmalloc_array(vcount, sizeof(*microvolt), GFP_KERNEL);
432         if (!microvolt)
433                 return -ENOMEM;
434
435         ret = of_property_read_u32_array(opp->np, name, microvolt, vcount);
436         if (ret) {
437                 dev_err(dev, "%s: error parsing %s: %d\n", __func__, name, ret);
438                 ret = -EINVAL;
439                 goto free_microvolt;
440         }
441
442         /* Search for "opp-microamp-<name>" */
443         prop = NULL;
444         if (opp_table->prop_name) {
445                 snprintf(name, sizeof(name), "opp-microamp-%s",
446                          opp_table->prop_name);
447                 prop = of_find_property(opp->np, name, NULL);
448         }
449
450         if (!prop) {
451                 /* Search for "opp-microamp" */
452                 sprintf(name, "opp-microamp");
453                 prop = of_find_property(opp->np, name, NULL);
454         }
455
456         if (prop) {
457                 icount = of_property_count_u32_elems(opp->np, name);
458                 if (icount < 0) {
459                         dev_err(dev, "%s: Invalid %s property (%d)\n", __func__,
460                                 name, icount);
461                         ret = icount;
462                         goto free_microvolt;
463                 }
464
465                 if (icount != supplies) {
466                         dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
467                                 __func__, name, icount, supplies);
468                         ret = -EINVAL;
469                         goto free_microvolt;
470                 }
471
472                 microamp = kmalloc_array(icount, sizeof(*microamp), GFP_KERNEL);
473                 if (!microamp) {
474                         ret = -EINVAL;
475                         goto free_microvolt;
476                 }
477
478                 ret = of_property_read_u32_array(opp->np, name, microamp,
479                                                  icount);
480                 if (ret) {
481                         dev_err(dev, "%s: error parsing %s: %d\n", __func__,
482                                 name, ret);
483                         ret = -EINVAL;
484                         goto free_microamp;
485                 }
486         }
487
488         for (i = 0, j = 0; i < supplies; i++) {
489                 opp->supplies[i].u_volt = microvolt[j++];
490
491                 if (vcount == supplies) {
492                         opp->supplies[i].u_volt_min = opp->supplies[i].u_volt;
493                         opp->supplies[i].u_volt_max = opp->supplies[i].u_volt;
494                 } else {
495                         opp->supplies[i].u_volt_min = microvolt[j++];
496                         opp->supplies[i].u_volt_max = microvolt[j++];
497                 }
498
499                 if (microamp)
500                         opp->supplies[i].u_amp = microamp[i];
501         }
502
503 free_microamp:
504         kfree(microamp);
505 free_microvolt:
506         kfree(microvolt);
507
508         return ret;
509 }
510
511 /**
512  * dev_pm_opp_of_remove_table() - Free OPP table entries created from static DT
513  *                                entries
514  * @dev:        device pointer used to lookup OPP table.
515  *
516  * Free OPPs created using static entries present in DT.
517  */
518 void dev_pm_opp_of_remove_table(struct device *dev)
519 {
520         _dev_pm_opp_find_and_remove_table(dev);
521 }
522 EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table);
523
524 /**
525  * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings)
526  * @opp_table:  OPP table
527  * @dev:        device for which we do this operation
528  * @np:         device node
529  *
530  * This function adds an opp definition to the opp table and returns status. The
531  * opp can be controlled using dev_pm_opp_enable/disable functions and may be
532  * removed by dev_pm_opp_remove.
533  *
534  * Return:
535  * Valid OPP pointer:
536  *              On success
537  * NULL:
538  *              Duplicate OPPs (both freq and volt are same) and opp->available
539  *              OR if the OPP is not supported by hardware.
540  * ERR_PTR(-EEXIST):
541  *              Freq are same and volt are different OR
542  *              Duplicate OPPs (both freq and volt are same) and !opp->available
543  * ERR_PTR(-ENOMEM):
544  *              Memory allocation failure
545  * ERR_PTR(-EINVAL):
546  *              Failed parsing the OPP node
547  */
548 static struct dev_pm_opp *_opp_add_static_v2(struct opp_table *opp_table,
549                 struct device *dev, struct device_node *np)
550 {
551         struct dev_pm_opp *new_opp;
552         u64 rate = 0;
553         u32 val;
554         int ret;
555         bool rate_not_available = false;
556
557         new_opp = _opp_allocate(opp_table);
558         if (!new_opp)
559                 return ERR_PTR(-ENOMEM);
560
561         ret = of_property_read_u64(np, "opp-hz", &rate);
562         if (ret < 0) {
563                 /* "opp-hz" is optional for devices like power domains. */
564                 if (!opp_table->is_genpd) {
565                         dev_err(dev, "%s: opp-hz not found\n", __func__);
566                         goto free_opp;
567                 }
568
569                 rate_not_available = true;
570         } else {
571                 /*
572                  * Rate is defined as an unsigned long in clk API, and so
573                  * casting explicitly to its type. Must be fixed once rate is 64
574                  * bit guaranteed in clk API.
575                  */
576                 new_opp->rate = (unsigned long)rate;
577         }
578
579         of_property_read_u32(np, "opp-level", &new_opp->level);
580
581         /* Check if the OPP supports hardware's hierarchy of versions or not */
582         if (!_opp_is_supported(dev, opp_table, np)) {
583                 dev_dbg(dev, "OPP not supported by hardware: %llu\n", rate);
584                 goto free_opp;
585         }
586
587         new_opp->turbo = of_property_read_bool(np, "turbo-mode");
588
589         new_opp->np = np;
590         new_opp->dynamic = false;
591         new_opp->available = true;
592
593         ret = _of_opp_alloc_required_opps(opp_table, new_opp);
594         if (ret)
595                 goto free_opp;
596
597         if (!of_property_read_u32(np, "clock-latency-ns", &val))
598                 new_opp->clock_latency_ns = val;
599
600         ret = opp_parse_supplies(new_opp, dev, opp_table);
601         if (ret)
602                 goto free_required_opps;
603
604         if (opp_table->is_genpd)
605                 new_opp->pstate = pm_genpd_opp_to_performance_state(dev, new_opp);
606
607         ret = _opp_add(dev, new_opp, opp_table, rate_not_available);
608         if (ret) {
609                 /* Don't return error for duplicate OPPs */
610                 if (ret == -EBUSY)
611                         ret = 0;
612                 goto free_required_opps;
613         }
614
615         /* OPP to select on device suspend */
616         if (of_property_read_bool(np, "opp-suspend")) {
617                 if (opp_table->suspend_opp) {
618                         /* Pick the OPP with higher rate as suspend OPP */
619                         if (new_opp->rate > opp_table->suspend_opp->rate) {
620                                 opp_table->suspend_opp->suspend = false;
621                                 new_opp->suspend = true;
622                                 opp_table->suspend_opp = new_opp;
623                         }
624                 } else {
625                         new_opp->suspend = true;
626                         opp_table->suspend_opp = new_opp;
627                 }
628         }
629
630         if (new_opp->clock_latency_ns > opp_table->clock_latency_ns_max)
631                 opp_table->clock_latency_ns_max = new_opp->clock_latency_ns;
632
633         pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu\n",
634                  __func__, new_opp->turbo, new_opp->rate,
635                  new_opp->supplies[0].u_volt, new_opp->supplies[0].u_volt_min,
636                  new_opp->supplies[0].u_volt_max, new_opp->clock_latency_ns);
637
638         /*
639          * Notify the changes in the availability of the operable
640          * frequency/voltage list.
641          */
642         blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ADD, new_opp);
643         return new_opp;
644
645 free_required_opps:
646         _of_opp_free_required_opps(opp_table, new_opp);
647 free_opp:
648         _opp_free(new_opp);
649
650         return ERR_PTR(ret);
651 }
652
653 /* Initializes OPP tables based on new bindings */
654 static int _of_add_opp_table_v2(struct device *dev, struct opp_table *opp_table)
655 {
656         struct device_node *np;
657         int ret, count = 0, pstate_count = 0;
658         struct dev_pm_opp *opp;
659
660         /* OPP table is already initialized for the device */
661         if (opp_table->parsed_static_opps) {
662                 kref_get(&opp_table->list_kref);
663                 return 0;
664         }
665
666         /*
667          * Re-initialize list_kref every time we add static OPPs to the OPP
668          * table as the reference count may be 0 after the last tie static OPPs
669          * were removed.
670          */
671         kref_init(&opp_table->list_kref);
672
673         /* We have opp-table node now, iterate over it and add OPPs */
674         for_each_available_child_of_node(opp_table->np, np) {
675                 opp = _opp_add_static_v2(opp_table, dev, np);
676                 if (IS_ERR(opp)) {
677                         ret = PTR_ERR(opp);
678                         dev_err(dev, "%s: Failed to add OPP, %d\n", __func__,
679                                 ret);
680                         of_node_put(np);
681                         return ret;
682                 } else if (opp) {
683                         count++;
684                 }
685         }
686
687         /* There should be one of more OPP defined */
688         if (WARN_ON(!count))
689                 return -ENOENT;
690
691         list_for_each_entry(opp, &opp_table->opp_list, node)
692                 pstate_count += !!opp->pstate;
693
694         /* Either all or none of the nodes shall have performance state set */
695         if (pstate_count && pstate_count != count) {
696                 dev_err(dev, "Not all nodes have performance state set (%d: %d)\n",
697                         count, pstate_count);
698                 return -ENOENT;
699         }
700
701         if (pstate_count)
702                 opp_table->genpd_performance_state = true;
703
704         opp_table->parsed_static_opps = true;
705
706         return 0;
707 }
708
709 /* Initializes OPP tables based on old-deprecated bindings */
710 static int _of_add_opp_table_v1(struct device *dev, struct opp_table *opp_table)
711 {
712         const struct property *prop;
713         const __be32 *val;
714         int nr, ret = 0;
715
716         prop = of_find_property(dev->of_node, "operating-points", NULL);
717         if (!prop)
718                 return -ENODEV;
719         if (!prop->value)
720                 return -ENODATA;
721
722         /*
723          * Each OPP is a set of tuples consisting of frequency and
724          * voltage like <freq-kHz vol-uV>.
725          */
726         nr = prop->length / sizeof(u32);
727         if (nr % 2) {
728                 dev_err(dev, "%s: Invalid OPP table\n", __func__);
729                 return -EINVAL;
730         }
731
732         val = prop->value;
733         while (nr) {
734                 unsigned long freq = be32_to_cpup(val++) * 1000;
735                 unsigned long volt = be32_to_cpup(val++);
736
737                 ret = _opp_add_v1(opp_table, dev, freq, volt, false);
738                 if (ret) {
739                         dev_err(dev, "%s: Failed to add OPP %ld (%d)\n",
740                                 __func__, freq, ret);
741                         return ret;
742                 }
743                 nr -= 2;
744         }
745
746         return ret;
747 }
748
749 /**
750  * dev_pm_opp_of_add_table() - Initialize opp table from device tree
751  * @dev:        device pointer used to lookup OPP table.
752  *
753  * Register the initial OPP table with the OPP library for given device.
754  *
755  * Return:
756  * 0            On success OR
757  *              Duplicate OPPs (both freq and volt are same) and opp->available
758  * -EEXIST      Freq are same and volt are different OR
759  *              Duplicate OPPs (both freq and volt are same) and !opp->available
760  * -ENOMEM      Memory allocation failure
761  * -ENODEV      when 'operating-points' property is not found or is invalid data
762  *              in device node.
763  * -ENODATA     when empty 'operating-points' property is found
764  * -EINVAL      when invalid entries are found in opp-v2 table
765  */
766 int dev_pm_opp_of_add_table(struct device *dev)
767 {
768         struct opp_table *opp_table;
769         int ret;
770
771         opp_table = dev_pm_opp_get_opp_table_indexed(dev, 0);
772         if (!opp_table)
773                 return -ENOMEM;
774
775         /*
776          * OPPs have two version of bindings now. Also try the old (v1)
777          * bindings for backward compatibility with older dtbs.
778          */
779         if (opp_table->np)
780                 ret = _of_add_opp_table_v2(dev, opp_table);
781         else
782                 ret = _of_add_opp_table_v1(dev, opp_table);
783
784         if (ret)
785                 dev_pm_opp_put_opp_table(opp_table);
786
787         return ret;
788 }
789 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table);
790
791 /**
792  * dev_pm_opp_of_add_table_indexed() - Initialize indexed opp table from device tree
793  * @dev:        device pointer used to lookup OPP table.
794  * @index:      Index number.
795  *
796  * Register the initial OPP table with the OPP library for given device only
797  * using the "operating-points-v2" property.
798  *
799  * Return:
800  * 0            On success OR
801  *              Duplicate OPPs (both freq and volt are same) and opp->available
802  * -EEXIST      Freq are same and volt are different OR
803  *              Duplicate OPPs (both freq and volt are same) and !opp->available
804  * -ENOMEM      Memory allocation failure
805  * -ENODEV      when 'operating-points' property is not found or is invalid data
806  *              in device node.
807  * -ENODATA     when empty 'operating-points' property is found
808  * -EINVAL      when invalid entries are found in opp-v2 table
809  */
810 int dev_pm_opp_of_add_table_indexed(struct device *dev, int index)
811 {
812         struct opp_table *opp_table;
813         int ret, count;
814
815         if (index) {
816                 /*
817                  * If only one phandle is present, then the same OPP table
818                  * applies for all index requests.
819                  */
820                 count = of_count_phandle_with_args(dev->of_node,
821                                                    "operating-points-v2", NULL);
822                 if (count == 1)
823                         index = 0;
824         }
825
826         opp_table = dev_pm_opp_get_opp_table_indexed(dev, index);
827         if (!opp_table)
828                 return -ENOMEM;
829
830         ret = _of_add_opp_table_v2(dev, opp_table);
831         if (ret)
832                 dev_pm_opp_put_opp_table(opp_table);
833
834         return ret;
835 }
836 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table_indexed);
837
838 /* CPU device specific helpers */
839
840 /**
841  * dev_pm_opp_of_cpumask_remove_table() - Removes OPP table for @cpumask
842  * @cpumask:    cpumask for which OPP table needs to be removed
843  *
844  * This removes the OPP tables for CPUs present in the @cpumask.
845  * This should be used only to remove static entries created from DT.
846  */
847 void dev_pm_opp_of_cpumask_remove_table(const struct cpumask *cpumask)
848 {
849         _dev_pm_opp_cpumask_remove_table(cpumask, -1);
850 }
851 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_remove_table);
852
853 /**
854  * dev_pm_opp_of_cpumask_add_table() - Adds OPP table for @cpumask
855  * @cpumask:    cpumask for which OPP table needs to be added.
856  *
857  * This adds the OPP tables for CPUs present in the @cpumask.
858  */
859 int dev_pm_opp_of_cpumask_add_table(const struct cpumask *cpumask)
860 {
861         struct device *cpu_dev;
862         int cpu, ret;
863
864         if (WARN_ON(cpumask_empty(cpumask)))
865                 return -ENODEV;
866
867         for_each_cpu(cpu, cpumask) {
868                 cpu_dev = get_cpu_device(cpu);
869                 if (!cpu_dev) {
870                         pr_err("%s: failed to get cpu%d device\n", __func__,
871                                cpu);
872                         ret = -ENODEV;
873                         goto remove_table;
874                 }
875
876                 ret = dev_pm_opp_of_add_table(cpu_dev);
877                 if (ret) {
878                         /*
879                          * OPP may get registered dynamically, don't print error
880                          * message here.
881                          */
882                         pr_debug("%s: couldn't find opp table for cpu:%d, %d\n",
883                                  __func__, cpu, ret);
884
885                         goto remove_table;
886                 }
887         }
888
889         return 0;
890
891 remove_table:
892         /* Free all other OPPs */
893         _dev_pm_opp_cpumask_remove_table(cpumask, cpu);
894
895         return ret;
896 }
897 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_add_table);
898
899 /*
900  * Works only for OPP v2 bindings.
901  *
902  * Returns -ENOENT if operating-points-v2 bindings aren't supported.
903  */
904 /**
905  * dev_pm_opp_of_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with
906  *                                    @cpu_dev using operating-points-v2
907  *                                    bindings.
908  *
909  * @cpu_dev:    CPU device for which we do this operation
910  * @cpumask:    cpumask to update with information of sharing CPUs
911  *
912  * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev.
913  *
914  * Returns -ENOENT if operating-points-v2 isn't present for @cpu_dev.
915  */
916 int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev,
917                                    struct cpumask *cpumask)
918 {
919         struct device_node *np, *tmp_np, *cpu_np;
920         int cpu, ret = 0;
921
922         /* Get OPP descriptor node */
923         np = dev_pm_opp_of_get_opp_desc_node(cpu_dev);
924         if (!np) {
925                 dev_dbg(cpu_dev, "%s: Couldn't find opp node.\n", __func__);
926                 return -ENOENT;
927         }
928
929         cpumask_set_cpu(cpu_dev->id, cpumask);
930
931         /* OPPs are shared ? */
932         if (!of_property_read_bool(np, "opp-shared"))
933                 goto put_cpu_node;
934
935         for_each_possible_cpu(cpu) {
936                 if (cpu == cpu_dev->id)
937                         continue;
938
939                 cpu_np = of_cpu_device_node_get(cpu);
940                 if (!cpu_np) {
941                         dev_err(cpu_dev, "%s: failed to get cpu%d node\n",
942                                 __func__, cpu);
943                         ret = -ENOENT;
944                         goto put_cpu_node;
945                 }
946
947                 /* Get OPP descriptor node */
948                 tmp_np = _opp_of_get_opp_desc_node(cpu_np, 0);
949                 of_node_put(cpu_np);
950                 if (!tmp_np) {
951                         pr_err("%pOF: Couldn't find opp node\n", cpu_np);
952                         ret = -ENOENT;
953                         goto put_cpu_node;
954                 }
955
956                 /* CPUs are sharing opp node */
957                 if (np == tmp_np)
958                         cpumask_set_cpu(cpu, cpumask);
959
960                 of_node_put(tmp_np);
961         }
962
963 put_cpu_node:
964         of_node_put(np);
965         return ret;
966 }
967 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus);
968
969 /**
970  * of_get_required_opp_performance_state() - Search for required OPP and return its performance state.
971  * @np: Node that contains the "required-opps" property.
972  * @index: Index of the phandle to parse.
973  *
974  * Returns the performance state of the OPP pointed out by the "required-opps"
975  * property at @index in @np.
976  *
977  * Return: Zero or positive performance state on success, otherwise negative
978  * value on errors.
979  */
980 int of_get_required_opp_performance_state(struct device_node *np, int index)
981 {
982         struct dev_pm_opp *opp;
983         struct device_node *required_np;
984         struct opp_table *opp_table;
985         int pstate = -EINVAL;
986
987         required_np = of_parse_required_opp(np, index);
988         if (!required_np)
989                 return -EINVAL;
990
991         opp_table = _find_table_of_opp_np(required_np);
992         if (IS_ERR(opp_table)) {
993                 pr_err("%s: Failed to find required OPP table %pOF: %ld\n",
994                        __func__, np, PTR_ERR(opp_table));
995                 goto put_required_np;
996         }
997
998         opp = _find_opp_of_np(opp_table, required_np);
999         if (opp) {
1000                 pstate = opp->pstate;
1001                 dev_pm_opp_put(opp);
1002         }
1003
1004         dev_pm_opp_put_opp_table(opp_table);
1005
1006 put_required_np:
1007         of_node_put(required_np);
1008
1009         return pstate;
1010 }
1011 EXPORT_SYMBOL_GPL(of_get_required_opp_performance_state);
1012
1013 /**
1014  * dev_pm_opp_get_of_node() - Gets the DT node corresponding to an opp
1015  * @opp:        opp for which DT node has to be returned for
1016  *
1017  * Return: DT node corresponding to the opp, else 0 on success.
1018  *
1019  * The caller needs to put the node with of_node_put() after using it.
1020  */
1021 struct device_node *dev_pm_opp_get_of_node(struct dev_pm_opp *opp)
1022 {
1023         if (IS_ERR_OR_NULL(opp)) {
1024                 pr_err("%s: Invalid parameters\n", __func__);
1025                 return NULL;
1026         }
1027
1028         return of_node_get(opp->np);
1029 }
1030 EXPORT_SYMBOL_GPL(dev_pm_opp_get_of_node);
1031
1032 /*
1033  * Callback function provided to the Energy Model framework upon registration.
1034  * This computes the power estimated by @CPU at @kHz if it is the frequency
1035  * of an existing OPP, or at the frequency of the first OPP above @kHz otherwise
1036  * (see dev_pm_opp_find_freq_ceil()). This function updates @kHz to the ceiled
1037  * frequency and @mW to the associated power. The power is estimated as
1038  * P = C * V^2 * f with C being the CPU's capacitance and V and f respectively
1039  * the voltage and frequency of the OPP.
1040  *
1041  * Returns -ENODEV if the CPU device cannot be found, -EINVAL if the power
1042  * calculation failed because of missing parameters, 0 otherwise.
1043  */
1044 static int __maybe_unused _get_cpu_power(unsigned long *mW, unsigned long *kHz,
1045                                          int cpu)
1046 {
1047         struct device *cpu_dev;
1048         struct dev_pm_opp *opp;
1049         struct device_node *np;
1050         unsigned long mV, Hz;
1051         u32 cap;
1052         u64 tmp;
1053         int ret;
1054
1055         cpu_dev = get_cpu_device(cpu);
1056         if (!cpu_dev)
1057                 return -ENODEV;
1058
1059         np = of_node_get(cpu_dev->of_node);
1060         if (!np)
1061                 return -EINVAL;
1062
1063         ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1064         of_node_put(np);
1065         if (ret)
1066                 return -EINVAL;
1067
1068         Hz = *kHz * 1000;
1069         opp = dev_pm_opp_find_freq_ceil(cpu_dev, &Hz);
1070         if (IS_ERR(opp))
1071                 return -EINVAL;
1072
1073         mV = dev_pm_opp_get_voltage(opp) / 1000;
1074         dev_pm_opp_put(opp);
1075         if (!mV)
1076                 return -EINVAL;
1077
1078         tmp = (u64)cap * mV * mV * (Hz / 1000000);
1079         do_div(tmp, 1000000000);
1080
1081         *mW = (unsigned long)tmp;
1082         *kHz = Hz / 1000;
1083
1084         return 0;
1085 }
1086
1087 /**
1088  * dev_pm_opp_of_register_em() - Attempt to register an Energy Model
1089  * @cpus        : CPUs for which an Energy Model has to be registered
1090  *
1091  * This checks whether the "dynamic-power-coefficient" devicetree property has
1092  * been specified, and tries to register an Energy Model with it if it has.
1093  */
1094 void dev_pm_opp_of_register_em(struct cpumask *cpus)
1095 {
1096         struct em_data_callback em_cb = EM_DATA_CB(_get_cpu_power);
1097         int ret, nr_opp, cpu = cpumask_first(cpus);
1098         struct device *cpu_dev;
1099         struct device_node *np;
1100         u32 cap;
1101
1102         cpu_dev = get_cpu_device(cpu);
1103         if (!cpu_dev)
1104                 return;
1105
1106         nr_opp = dev_pm_opp_get_opp_count(cpu_dev);
1107         if (nr_opp <= 0)
1108                 return;
1109
1110         np = of_node_get(cpu_dev->of_node);
1111         if (!np)
1112                 return;
1113
1114         /*
1115          * Register an EM only if the 'dynamic-power-coefficient' property is
1116          * set in devicetree. It is assumed the voltage values are known if that
1117          * property is set since it is useless otherwise. If voltages are not
1118          * known, just let the EM registration fail with an error to alert the
1119          * user about the inconsistent configuration.
1120          */
1121         ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1122         of_node_put(np);
1123         if (ret || !cap)
1124                 return;
1125
1126         em_register_perf_domain(cpus, nr_opp, &em_cb);
1127 }
1128 EXPORT_SYMBOL_GPL(dev_pm_opp_of_register_em);