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