1 // SPDX-License-Identifier: GPL-2.0-only
3 * Generic OPP OF helpers
5 * Copyright (C) 2009-2010 Texas Instruments Incorporated.
11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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>
25 * Returns opp descriptor node for a device node, caller must
28 static struct device_node *_opp_of_get_opp_desc_node(struct device_node *np,
31 /* "operating-points-v2" can be an array for power domain providers */
32 return of_parse_phandle(np, "operating-points-v2", index);
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)
38 return _opp_of_get_opp_desc_node(dev->of_node, 0);
40 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_opp_desc_node);
42 struct opp_table *_managed_opp(struct device *dev, int index)
44 struct opp_table *opp_table, *managed_table = NULL;
45 struct device_node *np;
47 np = _opp_of_get_opp_desc_node(dev->of_node, index);
51 list_for_each_entry(opp_table, &opp_tables, node) {
52 if (opp_table->np == np) {
54 * Multiple devices can point to the same OPP table and
55 * so will have same node-pointer, np.
57 * But the OPPs will be considered as shared only if the
58 * OPP table contains a "opp-shared" property.
60 if (opp_table->shared_opp == OPP_TABLE_ACCESS_SHARED) {
61 _get_opp_table_kref(opp_table);
62 managed_table = opp_table;
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)
78 struct dev_pm_opp *opp;
80 lockdep_assert_held(&opp_table_lock);
82 mutex_lock(&opp_table->lock);
84 list_for_each_entry(opp, &opp_table->opp_list, node) {
85 if (opp->np == opp_np) {
87 mutex_unlock(&opp_table->lock);
92 mutex_unlock(&opp_table->lock);
97 static struct device_node *of_parse_required_opp(struct device_node *np,
100 struct device_node *required_np;
102 required_np = of_parse_phandle(np, "required-opps", index);
103 if (unlikely(!required_np)) {
104 pr_err("%s: Unable to parse required-opps: %pOF, index: %d\n",
105 __func__, np, index);
111 /* The caller must call dev_pm_opp_put_opp_table() after the table is used */
112 static struct opp_table *_find_table_of_opp_np(struct device_node *opp_np)
114 struct opp_table *opp_table;
115 struct device_node *opp_table_np;
117 lockdep_assert_held(&opp_table_lock);
119 opp_table_np = of_get_parent(opp_np);
123 /* It is safe to put the node now as all we need now is its address */
124 of_node_put(opp_table_np);
126 list_for_each_entry(opp_table, &opp_tables, node) {
127 if (opp_table_np == opp_table->np) {
128 _get_opp_table_kref(opp_table);
134 return ERR_PTR(-ENODEV);
137 /* Free resources previously acquired by _opp_table_alloc_required_tables() */
138 static void _opp_table_free_required_tables(struct opp_table *opp_table)
140 struct opp_table **required_opp_tables = opp_table->required_opp_tables;
143 if (!required_opp_tables)
146 for (i = 0; i < opp_table->required_opp_count; i++) {
147 if (IS_ERR_OR_NULL(required_opp_tables[i]))
150 dev_pm_opp_put_opp_table(required_opp_tables[i]);
153 kfree(required_opp_tables);
155 opp_table->required_opp_count = 0;
156 opp_table->required_opp_tables = NULL;
160 * Populate all devices and opp tables which are part of "required-opps" list.
161 * Checking only the first OPP node should be enough.
163 static void _opp_table_alloc_required_tables(struct opp_table *opp_table,
165 struct device_node *opp_np)
167 struct opp_table **required_opp_tables;
168 struct device_node *required_np, *np;
171 /* Traversing the first OPP node is all we need */
172 np = of_get_next_available_child(opp_np, NULL);
174 dev_err(dev, "Empty OPP table\n");
178 count = of_count_phandle_with_args(np, "required-opps", NULL);
182 required_opp_tables = kcalloc(count, sizeof(*required_opp_tables),
184 if (!required_opp_tables)
187 opp_table->required_opp_tables = required_opp_tables;
188 opp_table->required_opp_count = count;
190 for (i = 0; i < count; i++) {
191 required_np = of_parse_required_opp(np, i);
193 goto free_required_tables;
195 required_opp_tables[i] = _find_table_of_opp_np(required_np);
196 of_node_put(required_np);
198 if (IS_ERR(required_opp_tables[i]))
199 goto free_required_tables;
202 * We only support genpd's OPPs in the "required-opps" for now,
203 * as we don't know how much about other cases. Error out if the
204 * required OPP doesn't belong to a genpd.
206 if (!required_opp_tables[i]->is_genpd) {
207 dev_err(dev, "required-opp doesn't belong to genpd: %pOF\n",
209 goto free_required_tables;
215 free_required_tables:
216 _opp_table_free_required_tables(opp_table);
221 void _of_init_opp_table(struct opp_table *opp_table, struct device *dev,
224 struct device_node *np, *opp_np;
228 * Only required for backward compatibility with v1 bindings, but isn't
229 * harmful for other cases. And so we do it unconditionally.
231 np = of_node_get(dev->of_node);
235 if (!of_property_read_u32(np, "clock-latency", &val))
236 opp_table->clock_latency_ns_max = val;
237 of_property_read_u32(np, "voltage-tolerance",
238 &opp_table->voltage_tolerance_v1);
240 if (of_find_property(np, "#power-domain-cells", NULL))
241 opp_table->is_genpd = true;
243 /* Get OPP table node */
244 opp_np = _opp_of_get_opp_desc_node(np, index);
250 if (of_property_read_bool(opp_np, "opp-shared"))
251 opp_table->shared_opp = OPP_TABLE_ACCESS_SHARED;
253 opp_table->shared_opp = OPP_TABLE_ACCESS_EXCLUSIVE;
255 opp_table->np = opp_np;
257 _opp_table_alloc_required_tables(opp_table, dev, opp_np);
261 void _of_clear_opp_table(struct opp_table *opp_table)
263 _opp_table_free_required_tables(opp_table);
267 * Release all resources previously acquired with a call to
268 * _of_opp_alloc_required_opps().
270 void _of_opp_free_required_opps(struct opp_table *opp_table,
271 struct dev_pm_opp *opp)
273 struct dev_pm_opp **required_opps = opp->required_opps;
279 for (i = 0; i < opp_table->required_opp_count; i++) {
280 if (!required_opps[i])
283 /* Put the reference back */
284 dev_pm_opp_put(required_opps[i]);
287 kfree(required_opps);
288 opp->required_opps = NULL;
291 /* Populate all required OPPs which are part of "required-opps" list */
292 static int _of_opp_alloc_required_opps(struct opp_table *opp_table,
293 struct dev_pm_opp *opp)
295 struct dev_pm_opp **required_opps;
296 struct opp_table *required_table;
297 struct device_node *np;
298 int i, ret, count = opp_table->required_opp_count;
303 required_opps = kcalloc(count, sizeof(*required_opps), GFP_KERNEL);
307 opp->required_opps = required_opps;
309 for (i = 0; i < count; i++) {
310 required_table = opp_table->required_opp_tables[i];
312 np = of_parse_required_opp(opp->np, i);
315 goto free_required_opps;
318 required_opps[i] = _find_opp_of_np(required_table, np);
321 if (!required_opps[i]) {
322 pr_err("%s: Unable to find required OPP node: %pOF (%d)\n",
323 __func__, opp->np, i);
325 goto free_required_opps;
332 _of_opp_free_required_opps(opp_table, opp);
337 static bool _opp_is_supported(struct device *dev, struct opp_table *opp_table,
338 struct device_node *np)
340 unsigned int count = opp_table->supported_hw_count;
344 if (!opp_table->supported_hw) {
346 * In the case that no supported_hw has been set by the
347 * platform but there is an opp-supported-hw value set for
348 * an OPP then the OPP should not be enabled as there is
349 * no way to see if the hardware supports it.
351 if (of_find_property(np, "opp-supported-hw", NULL))
358 ret = of_property_read_u32_index(np, "opp-supported-hw", count,
361 dev_warn(dev, "%s: failed to read opp-supported-hw property at index %d: %d\n",
362 __func__, count, ret);
366 /* Both of these are bitwise masks of the versions */
367 if (!(version & opp_table->supported_hw[count]))
374 static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,
375 struct opp_table *opp_table)
377 u32 *microvolt, *microamp = NULL;
378 int supplies = opp_table->regulator_count, vcount, icount, ret, i, j;
379 struct property *prop = NULL;
382 /* Search for "opp-microvolt-<name>" */
383 if (opp_table->prop_name) {
384 snprintf(name, sizeof(name), "opp-microvolt-%s",
385 opp_table->prop_name);
386 prop = of_find_property(opp->np, name, NULL);
390 /* Search for "opp-microvolt" */
391 sprintf(name, "opp-microvolt");
392 prop = of_find_property(opp->np, name, NULL);
394 /* Missing property isn't a problem, but an invalid entry is */
396 if (unlikely(supplies == -1)) {
397 /* Initialize regulator_count */
398 opp_table->regulator_count = 0;
405 dev_err(dev, "%s: opp-microvolt missing although OPP managing regulators\n",
411 if (unlikely(supplies == -1)) {
412 /* Initialize regulator_count */
413 supplies = opp_table->regulator_count = 1;
414 } else if (unlikely(!supplies)) {
415 dev_err(dev, "%s: opp-microvolt wasn't expected\n", __func__);
419 vcount = of_property_count_u32_elems(opp->np, name);
421 dev_err(dev, "%s: Invalid %s property (%d)\n",
422 __func__, name, vcount);
426 /* There can be one or three elements per supply */
427 if (vcount != supplies && vcount != supplies * 3) {
428 dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
429 __func__, name, vcount, supplies);
433 microvolt = kmalloc_array(vcount, sizeof(*microvolt), GFP_KERNEL);
437 ret = of_property_read_u32_array(opp->np, name, microvolt, vcount);
439 dev_err(dev, "%s: error parsing %s: %d\n", __func__, name, ret);
444 /* Search for "opp-microamp-<name>" */
446 if (opp_table->prop_name) {
447 snprintf(name, sizeof(name), "opp-microamp-%s",
448 opp_table->prop_name);
449 prop = of_find_property(opp->np, name, NULL);
453 /* Search for "opp-microamp" */
454 sprintf(name, "opp-microamp");
455 prop = of_find_property(opp->np, name, NULL);
459 icount = of_property_count_u32_elems(opp->np, name);
461 dev_err(dev, "%s: Invalid %s property (%d)\n", __func__,
467 if (icount != supplies) {
468 dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
469 __func__, name, icount, supplies);
474 microamp = kmalloc_array(icount, sizeof(*microamp), GFP_KERNEL);
480 ret = of_property_read_u32_array(opp->np, name, microamp,
483 dev_err(dev, "%s: error parsing %s: %d\n", __func__,
490 for (i = 0, j = 0; i < supplies; i++) {
491 opp->supplies[i].u_volt = microvolt[j++];
493 if (vcount == supplies) {
494 opp->supplies[i].u_volt_min = opp->supplies[i].u_volt;
495 opp->supplies[i].u_volt_max = opp->supplies[i].u_volt;
497 opp->supplies[i].u_volt_min = microvolt[j++];
498 opp->supplies[i].u_volt_max = microvolt[j++];
502 opp->supplies[i].u_amp = microamp[i];
514 * dev_pm_opp_of_remove_table() - Free OPP table entries created from static DT
516 * @dev: device pointer used to lookup OPP table.
518 * Free OPPs created using static entries present in DT.
520 void dev_pm_opp_of_remove_table(struct device *dev)
522 _dev_pm_opp_find_and_remove_table(dev);
524 EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table);
527 * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings)
528 * @opp_table: OPP table
529 * @dev: device for which we do this operation
532 * This function adds an opp definition to the opp table and returns status. The
533 * opp can be controlled using dev_pm_opp_enable/disable functions and may be
534 * removed by dev_pm_opp_remove.
540 * Duplicate OPPs (both freq and volt are same) and opp->available
541 * OR if the OPP is not supported by hardware.
543 * Freq are same and volt are different OR
544 * Duplicate OPPs (both freq and volt are same) and !opp->available
546 * Memory allocation failure
548 * Failed parsing the OPP node
550 static struct dev_pm_opp *_opp_add_static_v2(struct opp_table *opp_table,
551 struct device *dev, struct device_node *np)
553 struct dev_pm_opp *new_opp;
557 bool rate_not_available = false;
559 new_opp = _opp_allocate(opp_table);
561 return ERR_PTR(-ENOMEM);
563 ret = of_property_read_u64(np, "opp-hz", &rate);
565 /* "opp-hz" is optional for devices like power domains. */
566 if (!opp_table->is_genpd) {
567 dev_err(dev, "%s: opp-hz not found\n", __func__);
571 rate_not_available = true;
574 * Rate is defined as an unsigned long in clk API, and so
575 * casting explicitly to its type. Must be fixed once rate is 64
576 * bit guaranteed in clk API.
578 new_opp->rate = (unsigned long)rate;
581 of_property_read_u32(np, "opp-level", &new_opp->level);
583 /* Check if the OPP supports hardware's hierarchy of versions or not */
584 if (!_opp_is_supported(dev, opp_table, np)) {
585 dev_dbg(dev, "OPP not supported by hardware: %llu\n", rate);
589 new_opp->turbo = of_property_read_bool(np, "turbo-mode");
592 new_opp->dynamic = false;
593 new_opp->available = true;
595 ret = _of_opp_alloc_required_opps(opp_table, new_opp);
599 if (!of_property_read_u32(np, "clock-latency-ns", &val))
600 new_opp->clock_latency_ns = val;
602 ret = opp_parse_supplies(new_opp, dev, opp_table);
604 goto free_required_opps;
606 if (opp_table->is_genpd)
607 new_opp->pstate = pm_genpd_opp_to_performance_state(dev, new_opp);
609 ret = _opp_add(dev, new_opp, opp_table, rate_not_available);
611 /* Don't return error for duplicate OPPs */
614 goto free_required_opps;
617 /* OPP to select on device suspend */
618 if (of_property_read_bool(np, "opp-suspend")) {
619 if (opp_table->suspend_opp) {
620 /* Pick the OPP with higher rate as suspend OPP */
621 if (new_opp->rate > opp_table->suspend_opp->rate) {
622 opp_table->suspend_opp->suspend = false;
623 new_opp->suspend = true;
624 opp_table->suspend_opp = new_opp;
627 new_opp->suspend = true;
628 opp_table->suspend_opp = new_opp;
632 if (new_opp->clock_latency_ns > opp_table->clock_latency_ns_max)
633 opp_table->clock_latency_ns_max = new_opp->clock_latency_ns;
635 pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu\n",
636 __func__, new_opp->turbo, new_opp->rate,
637 new_opp->supplies[0].u_volt, new_opp->supplies[0].u_volt_min,
638 new_opp->supplies[0].u_volt_max, new_opp->clock_latency_ns);
641 * Notify the changes in the availability of the operable
642 * frequency/voltage list.
644 blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ADD, new_opp);
648 _of_opp_free_required_opps(opp_table, new_opp);
655 /* Initializes OPP tables based on new bindings */
656 static int _of_add_opp_table_v2(struct device *dev, struct opp_table *opp_table)
658 struct device_node *np;
659 int ret, count = 0, pstate_count = 0;
660 struct dev_pm_opp *opp;
662 /* OPP table is already initialized for the device */
663 if (opp_table->parsed_static_opps) {
664 kref_get(&opp_table->list_kref);
668 /* We have opp-table node now, iterate over it and add OPPs */
669 for_each_available_child_of_node(opp_table->np, np) {
670 opp = _opp_add_static_v2(opp_table, dev, np);
673 dev_err(dev, "%s: Failed to add OPP, %d\n", __func__,
682 /* There should be one of more OPP defined */
686 list_for_each_entry(opp, &opp_table->opp_list, node)
687 pstate_count += !!opp->pstate;
689 /* Either all or none of the nodes shall have performance state set */
690 if (pstate_count && pstate_count != count) {
691 dev_err(dev, "Not all nodes have performance state set (%d: %d)\n",
692 count, pstate_count);
697 opp_table->genpd_performance_state = true;
699 opp_table->parsed_static_opps = true;
704 /* Initializes OPP tables based on old-deprecated bindings */
705 static int _of_add_opp_table_v1(struct device *dev, struct opp_table *opp_table)
707 const struct property *prop;
711 prop = of_find_property(dev->of_node, "operating-points", NULL);
718 * Each OPP is a set of tuples consisting of frequency and
719 * voltage like <freq-kHz vol-uV>.
721 nr = prop->length / sizeof(u32);
723 dev_err(dev, "%s: Invalid OPP table\n", __func__);
729 unsigned long freq = be32_to_cpup(val++) * 1000;
730 unsigned long volt = be32_to_cpup(val++);
732 ret = _opp_add_v1(opp_table, dev, freq, volt, false);
734 dev_err(dev, "%s: Failed to add OPP %ld (%d)\n",
735 __func__, freq, ret);
745 * dev_pm_opp_of_add_table() - Initialize opp table from device tree
746 * @dev: device pointer used to lookup OPP table.
748 * Register the initial OPP table with the OPP library for given device.
752 * Duplicate OPPs (both freq and volt are same) and opp->available
753 * -EEXIST Freq are same and volt are different OR
754 * Duplicate OPPs (both freq and volt are same) and !opp->available
755 * -ENOMEM Memory allocation failure
756 * -ENODEV when 'operating-points' property is not found or is invalid data
758 * -ENODATA when empty 'operating-points' property is found
759 * -EINVAL when invalid entries are found in opp-v2 table
761 int dev_pm_opp_of_add_table(struct device *dev)
763 struct opp_table *opp_table;
766 opp_table = dev_pm_opp_get_opp_table_indexed(dev, 0);
771 * OPPs have two version of bindings now. Also try the old (v1)
772 * bindings for backward compatibility with older dtbs.
775 ret = _of_add_opp_table_v2(dev, opp_table);
777 ret = _of_add_opp_table_v1(dev, opp_table);
780 dev_pm_opp_put_opp_table(opp_table);
784 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table);
787 * dev_pm_opp_of_add_table_indexed() - Initialize indexed opp table from device tree
788 * @dev: device pointer used to lookup OPP table.
789 * @index: Index number.
791 * Register the initial OPP table with the OPP library for given device only
792 * using the "operating-points-v2" property.
796 * Duplicate OPPs (both freq and volt are same) and opp->available
797 * -EEXIST Freq are same and volt are different OR
798 * Duplicate OPPs (both freq and volt are same) and !opp->available
799 * -ENOMEM Memory allocation failure
800 * -ENODEV when 'operating-points' property is not found or is invalid data
802 * -ENODATA when empty 'operating-points' property is found
803 * -EINVAL when invalid entries are found in opp-v2 table
805 int dev_pm_opp_of_add_table_indexed(struct device *dev, int index)
807 struct opp_table *opp_table;
812 * If only one phandle is present, then the same OPP table
813 * applies for all index requests.
815 count = of_count_phandle_with_args(dev->of_node,
816 "operating-points-v2", NULL);
821 opp_table = dev_pm_opp_get_opp_table_indexed(dev, index);
825 ret = _of_add_opp_table_v2(dev, opp_table);
827 dev_pm_opp_put_opp_table(opp_table);
831 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table_indexed);
833 /* CPU device specific helpers */
836 * dev_pm_opp_of_cpumask_remove_table() - Removes OPP table for @cpumask
837 * @cpumask: cpumask for which OPP table needs to be removed
839 * This removes the OPP tables for CPUs present in the @cpumask.
840 * This should be used only to remove static entries created from DT.
842 void dev_pm_opp_of_cpumask_remove_table(const struct cpumask *cpumask)
844 _dev_pm_opp_cpumask_remove_table(cpumask, -1);
846 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_remove_table);
849 * dev_pm_opp_of_cpumask_add_table() - Adds OPP table for @cpumask
850 * @cpumask: cpumask for which OPP table needs to be added.
852 * This adds the OPP tables for CPUs present in the @cpumask.
854 int dev_pm_opp_of_cpumask_add_table(const struct cpumask *cpumask)
856 struct device *cpu_dev;
859 if (WARN_ON(cpumask_empty(cpumask)))
862 for_each_cpu(cpu, cpumask) {
863 cpu_dev = get_cpu_device(cpu);
865 pr_err("%s: failed to get cpu%d device\n", __func__,
871 ret = dev_pm_opp_of_add_table(cpu_dev);
874 * OPP may get registered dynamically, don't print error
877 pr_debug("%s: couldn't find opp table for cpu:%d, %d\n",
887 /* Free all other OPPs */
888 _dev_pm_opp_cpumask_remove_table(cpumask, cpu);
892 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_add_table);
895 * Works only for OPP v2 bindings.
897 * Returns -ENOENT if operating-points-v2 bindings aren't supported.
900 * dev_pm_opp_of_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with
901 * @cpu_dev using operating-points-v2
904 * @cpu_dev: CPU device for which we do this operation
905 * @cpumask: cpumask to update with information of sharing CPUs
907 * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev.
909 * Returns -ENOENT if operating-points-v2 isn't present for @cpu_dev.
911 int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev,
912 struct cpumask *cpumask)
914 struct device_node *np, *tmp_np, *cpu_np;
917 /* Get OPP descriptor node */
918 np = dev_pm_opp_of_get_opp_desc_node(cpu_dev);
920 dev_dbg(cpu_dev, "%s: Couldn't find opp node.\n", __func__);
924 cpumask_set_cpu(cpu_dev->id, cpumask);
926 /* OPPs are shared ? */
927 if (!of_property_read_bool(np, "opp-shared"))
930 for_each_possible_cpu(cpu) {
931 if (cpu == cpu_dev->id)
934 cpu_np = of_cpu_device_node_get(cpu);
936 dev_err(cpu_dev, "%s: failed to get cpu%d node\n",
942 /* Get OPP descriptor node */
943 tmp_np = _opp_of_get_opp_desc_node(cpu_np, 0);
946 pr_err("%pOF: Couldn't find opp node\n", cpu_np);
951 /* CPUs are sharing opp node */
953 cpumask_set_cpu(cpu, cpumask);
962 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus);
965 * of_get_required_opp_performance_state() - Search for required OPP and return its performance state.
966 * @np: Node that contains the "required-opps" property.
967 * @index: Index of the phandle to parse.
969 * Returns the performance state of the OPP pointed out by the "required-opps"
970 * property at @index in @np.
972 * Return: Zero or positive performance state on success, otherwise negative
975 int of_get_required_opp_performance_state(struct device_node *np, int index)
977 struct dev_pm_opp *opp;
978 struct device_node *required_np;
979 struct opp_table *opp_table;
980 int pstate = -EINVAL;
982 required_np = of_parse_required_opp(np, index);
986 opp_table = _find_table_of_opp_np(required_np);
987 if (IS_ERR(opp_table)) {
988 pr_err("%s: Failed to find required OPP table %pOF: %ld\n",
989 __func__, np, PTR_ERR(opp_table));
990 goto put_required_np;
993 opp = _find_opp_of_np(opp_table, required_np);
995 pstate = opp->pstate;
999 dev_pm_opp_put_opp_table(opp_table);
1002 of_node_put(required_np);
1006 EXPORT_SYMBOL_GPL(of_get_required_opp_performance_state);
1009 * dev_pm_opp_get_of_node() - Gets the DT node corresponding to an opp
1010 * @opp: opp for which DT node has to be returned for
1012 * Return: DT node corresponding to the opp, else 0 on success.
1014 * The caller needs to put the node with of_node_put() after using it.
1016 struct device_node *dev_pm_opp_get_of_node(struct dev_pm_opp *opp)
1018 if (IS_ERR_OR_NULL(opp)) {
1019 pr_err("%s: Invalid parameters\n", __func__);
1023 return of_node_get(opp->np);
1025 EXPORT_SYMBOL_GPL(dev_pm_opp_get_of_node);
1028 * Callback function provided to the Energy Model framework upon registration.
1029 * This computes the power estimated by @CPU at @kHz if it is the frequency
1030 * of an existing OPP, or at the frequency of the first OPP above @kHz otherwise
1031 * (see dev_pm_opp_find_freq_ceil()). This function updates @kHz to the ceiled
1032 * frequency and @mW to the associated power. The power is estimated as
1033 * P = C * V^2 * f with C being the CPU's capacitance and V and f respectively
1034 * the voltage and frequency of the OPP.
1036 * Returns -ENODEV if the CPU device cannot be found, -EINVAL if the power
1037 * calculation failed because of missing parameters, 0 otherwise.
1039 static int __maybe_unused _get_cpu_power(unsigned long *mW, unsigned long *kHz,
1042 struct device *cpu_dev;
1043 struct dev_pm_opp *opp;
1044 struct device_node *np;
1045 unsigned long mV, Hz;
1050 cpu_dev = get_cpu_device(cpu);
1054 np = of_node_get(cpu_dev->of_node);
1058 ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1064 opp = dev_pm_opp_find_freq_ceil(cpu_dev, &Hz);
1068 mV = dev_pm_opp_get_voltage(opp) / 1000;
1069 dev_pm_opp_put(opp);
1073 tmp = (u64)cap * mV * mV * (Hz / 1000000);
1074 do_div(tmp, 1000000000);
1076 *mW = (unsigned long)tmp;
1083 * dev_pm_opp_of_register_em() - Attempt to register an Energy Model
1084 * @cpus : CPUs for which an Energy Model has to be registered
1086 * This checks whether the "dynamic-power-coefficient" devicetree property has
1087 * been specified, and tries to register an Energy Model with it if it has.
1089 void dev_pm_opp_of_register_em(struct cpumask *cpus)
1091 struct em_data_callback em_cb = EM_DATA_CB(_get_cpu_power);
1092 int ret, nr_opp, cpu = cpumask_first(cpus);
1093 struct device *cpu_dev;
1094 struct device_node *np;
1097 cpu_dev = get_cpu_device(cpu);
1101 nr_opp = dev_pm_opp_get_opp_count(cpu_dev);
1105 np = of_node_get(cpu_dev->of_node);
1110 * Register an EM only if the 'dynamic-power-coefficient' property is
1111 * set in devicetree. It is assumed the voltage values are known if that
1112 * property is set since it is useless otherwise. If voltages are not
1113 * known, just let the EM registration fail with an error to alert the
1114 * user about the inconsistent configuration.
1116 ret = of_property_read_u32(np, "dynamic-power-coefficient", &cap);
1121 em_register_perf_domain(cpus, nr_opp, &em_cb);
1123 EXPORT_SYMBOL_GPL(dev_pm_opp_of_register_em);