2 * Generic OPP OF helpers
4 * Copyright (C) 2009-2010 Texas Instruments Incorporated.
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as
11 * published by the Free Software Foundation.
14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
16 #include <linux/cpu.h>
17 #include <linux/errno.h>
18 #include <linux/device.h>
20 #include <linux/slab.h>
21 #include <linux/export.h>
25 static struct opp_table *_managed_opp(const struct device_node *np)
27 struct opp_table *opp_table;
29 list_for_each_entry_rcu(opp_table, &opp_tables, node) {
30 if (opp_table->np == np) {
32 * Multiple devices can point to the same OPP table and
33 * so will have same node-pointer, np.
35 * But the OPPs will be considered as shared only if the
36 * OPP table contains a "opp-shared" property.
38 if (opp_table->shared_opp == OPP_TABLE_ACCESS_SHARED)
48 void _of_init_opp_table(struct opp_table *opp_table, struct device *dev)
50 struct device_node *np;
53 * Only required for backward compatibility with v1 bindings, but isn't
54 * harmful for other cases. And so we do it unconditionally.
56 np = of_node_get(dev->of_node);
60 if (!of_property_read_u32(np, "clock-latency", &val))
61 opp_table->clock_latency_ns_max = val;
62 of_property_read_u32(np, "voltage-tolerance",
63 &opp_table->voltage_tolerance_v1);
68 static bool _opp_is_supported(struct device *dev, struct opp_table *opp_table,
69 struct device_node *np)
71 unsigned int count = opp_table->supported_hw_count;
75 if (!opp_table->supported_hw) {
77 * In the case that no supported_hw has been set by the
78 * platform but there is an opp-supported-hw value set for
79 * an OPP then the OPP should not be enabled as there is
80 * no way to see if the hardware supports it.
82 if (of_find_property(np, "opp-supported-hw", NULL))
89 ret = of_property_read_u32_index(np, "opp-supported-hw", count,
92 dev_warn(dev, "%s: failed to read opp-supported-hw property at index %d: %d\n",
93 __func__, count, ret);
97 /* Both of these are bitwise masks of the versions */
98 if (!(version & opp_table->supported_hw[count]))
105 static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,
106 struct opp_table *opp_table)
108 u32 *microvolt, *microamp = NULL;
109 int supplies, vcount, icount, ret, i, j;
110 struct property *prop = NULL;
113 supplies = opp_table->regulator_count ? opp_table->regulator_count : 1;
115 /* Search for "opp-microvolt-<name>" */
116 if (opp_table->prop_name) {
117 snprintf(name, sizeof(name), "opp-microvolt-%s",
118 opp_table->prop_name);
119 prop = of_find_property(opp->np, name, NULL);
123 /* Search for "opp-microvolt" */
124 sprintf(name, "opp-microvolt");
125 prop = of_find_property(opp->np, name, NULL);
127 /* Missing property isn't a problem, but an invalid entry is */
132 vcount = of_property_count_u32_elems(opp->np, name);
134 dev_err(dev, "%s: Invalid %s property (%d)\n",
135 __func__, name, vcount);
139 /* There can be one or three elements per supply */
140 if (vcount != supplies && vcount != supplies * 3) {
141 dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
142 __func__, name, vcount, supplies);
146 microvolt = kmalloc_array(vcount, sizeof(*microvolt), GFP_KERNEL);
150 ret = of_property_read_u32_array(opp->np, name, microvolt, vcount);
152 dev_err(dev, "%s: error parsing %s: %d\n", __func__, name, ret);
157 /* Search for "opp-microamp-<name>" */
159 if (opp_table->prop_name) {
160 snprintf(name, sizeof(name), "opp-microamp-%s",
161 opp_table->prop_name);
162 prop = of_find_property(opp->np, name, NULL);
166 /* Search for "opp-microamp" */
167 sprintf(name, "opp-microamp");
168 prop = of_find_property(opp->np, name, NULL);
172 icount = of_property_count_u32_elems(opp->np, name);
174 dev_err(dev, "%s: Invalid %s property (%d)\n", __func__,
180 if (icount != supplies) {
181 dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
182 __func__, name, icount, supplies);
187 microamp = kmalloc_array(icount, sizeof(*microamp), GFP_KERNEL);
193 ret = of_property_read_u32_array(opp->np, name, microamp,
196 dev_err(dev, "%s: error parsing %s: %d\n", __func__,
203 for (i = 0, j = 0; i < supplies; i++) {
204 opp->supplies[i].u_volt = microvolt[j++];
206 if (vcount == supplies) {
207 opp->supplies[i].u_volt_min = opp->supplies[i].u_volt;
208 opp->supplies[i].u_volt_max = opp->supplies[i].u_volt;
210 opp->supplies[i].u_volt_min = microvolt[j++];
211 opp->supplies[i].u_volt_max = microvolt[j++];
215 opp->supplies[i].u_amp = microamp[i];
227 * dev_pm_opp_of_remove_table() - Free OPP table entries created from static DT
229 * @dev: device pointer used to lookup OPP table.
231 * Free OPPs created using static entries present in DT.
233 * Locking: The internal opp_table and opp structures are RCU protected.
234 * Hence this function indirectly uses RCU updater strategy with mutex locks
235 * to keep the integrity of the internal data structures. Callers should ensure
236 * that this function is *NOT* called under RCU protection or in contexts where
237 * mutex cannot be locked.
239 void dev_pm_opp_of_remove_table(struct device *dev)
241 _dev_pm_opp_remove_table(dev, false);
243 EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table);
245 /* Returns opp descriptor node for a device, caller must do of_node_put() */
246 static struct device_node *_of_get_opp_desc_node(struct device *dev)
249 * TODO: Support for multiple OPP tables.
251 * There should be only ONE phandle present in "operating-points-v2"
255 return of_parse_phandle(dev->of_node, "operating-points-v2", 0);
259 * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings)
260 * @dev: device for which we do this operation
263 * This function adds an opp definition to the opp table and returns status. The
264 * opp can be controlled using dev_pm_opp_enable/disable functions and may be
265 * removed by dev_pm_opp_remove.
267 * Locking: The internal opp_table and opp structures are RCU protected.
268 * Hence this function internally uses RCU updater strategy with mutex locks
269 * to keep the integrity of the internal data structures. Callers should ensure
270 * that this function is *NOT* called under RCU protection or in contexts where
271 * mutex cannot be locked.
275 * Duplicate OPPs (both freq and volt are same) and opp->available
276 * -EEXIST Freq are same and volt are different OR
277 * Duplicate OPPs (both freq and volt are same) and !opp->available
278 * -ENOMEM Memory allocation failure
279 * -EINVAL Failed parsing the OPP node
281 static int _opp_add_static_v2(struct device *dev, struct device_node *np)
283 struct opp_table *opp_table;
284 struct dev_pm_opp *new_opp;
289 /* Hold our table modification lock here */
290 mutex_lock(&opp_table_lock);
292 new_opp = _allocate_opp(dev, &opp_table);
298 ret = of_property_read_u64(np, "opp-hz", &rate);
300 dev_err(dev, "%s: opp-hz not found\n", __func__);
304 /* Check if the OPP supports hardware's hierarchy of versions or not */
305 if (!_opp_is_supported(dev, opp_table, np)) {
306 dev_dbg(dev, "OPP not supported by hardware: %llu\n", rate);
311 * Rate is defined as an unsigned long in clk API, and so casting
312 * explicitly to its type. Must be fixed once rate is 64 bit
313 * guaranteed in clk API.
315 new_opp->rate = (unsigned long)rate;
316 new_opp->turbo = of_property_read_bool(np, "turbo-mode");
319 new_opp->dynamic = false;
320 new_opp->available = true;
322 if (!of_property_read_u32(np, "clock-latency-ns", &val))
323 new_opp->clock_latency_ns = val;
325 ret = opp_parse_supplies(new_opp, dev, opp_table);
329 ret = _opp_add(dev, new_opp, opp_table);
331 /* Don't return error for duplicate OPPs */
337 /* OPP to select on device suspend */
338 if (of_property_read_bool(np, "opp-suspend")) {
339 if (opp_table->suspend_opp) {
340 dev_warn(dev, "%s: Multiple suspend OPPs found (%lu %lu)\n",
341 __func__, opp_table->suspend_opp->rate,
344 new_opp->suspend = true;
345 opp_table->suspend_opp = new_opp;
349 if (new_opp->clock_latency_ns > opp_table->clock_latency_ns_max)
350 opp_table->clock_latency_ns_max = new_opp->clock_latency_ns;
352 mutex_unlock(&opp_table_lock);
354 pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu\n",
355 __func__, new_opp->turbo, new_opp->rate,
356 new_opp->supplies[0].u_volt, new_opp->supplies[0].u_volt_min,
357 new_opp->supplies[0].u_volt_max, new_opp->clock_latency_ns);
360 * Notify the changes in the availability of the operable
361 * frequency/voltage list.
363 srcu_notifier_call_chain(&opp_table->srcu_head, OPP_EVENT_ADD, new_opp);
367 _opp_remove(opp_table, new_opp, false);
369 mutex_unlock(&opp_table_lock);
373 /* Initializes OPP tables based on new bindings */
374 static int _of_add_opp_table_v2(struct device *dev, struct device_node *opp_np)
376 struct device_node *np;
377 struct opp_table *opp_table;
378 int ret = 0, count = 0;
380 mutex_lock(&opp_table_lock);
382 opp_table = _managed_opp(opp_np);
384 /* OPPs are already managed */
385 if (!_add_opp_dev(dev, opp_table))
387 mutex_unlock(&opp_table_lock);
390 mutex_unlock(&opp_table_lock);
392 /* We have opp-table node now, iterate over it and add OPPs */
393 for_each_available_child_of_node(opp_np, np) {
396 ret = _opp_add_static_v2(dev, np);
398 dev_err(dev, "%s: Failed to add OPP, %d\n", __func__,
404 /* There should be one of more OPP defined */
408 mutex_lock(&opp_table_lock);
410 opp_table = _find_opp_table(dev);
411 if (WARN_ON(IS_ERR(opp_table))) {
412 ret = PTR_ERR(opp_table);
413 mutex_unlock(&opp_table_lock);
417 opp_table->np = opp_np;
418 if (of_property_read_bool(opp_np, "opp-shared"))
419 opp_table->shared_opp = OPP_TABLE_ACCESS_SHARED;
421 opp_table->shared_opp = OPP_TABLE_ACCESS_EXCLUSIVE;
423 mutex_unlock(&opp_table_lock);
428 dev_pm_opp_of_remove_table(dev);
433 /* Initializes OPP tables based on old-deprecated bindings */
434 static int _of_add_opp_table_v1(struct device *dev)
436 const struct property *prop;
440 prop = of_find_property(dev->of_node, "operating-points", NULL);
447 * Each OPP is a set of tuples consisting of frequency and
448 * voltage like <freq-kHz vol-uV>.
450 nr = prop->length / sizeof(u32);
452 dev_err(dev, "%s: Invalid OPP table\n", __func__);
458 unsigned long freq = be32_to_cpup(val++) * 1000;
459 unsigned long volt = be32_to_cpup(val++);
461 if (_opp_add_v1(dev, freq, volt, false))
462 dev_warn(dev, "%s: Failed to add OPP %ld\n",
471 * dev_pm_opp_of_add_table() - Initialize opp table from device tree
472 * @dev: device pointer used to lookup OPP table.
474 * Register the initial OPP table with the OPP library for given device.
476 * Locking: The internal opp_table and opp structures are RCU protected.
477 * Hence this function indirectly uses RCU updater strategy with mutex locks
478 * to keep the integrity of the internal data structures. Callers should ensure
479 * that this function is *NOT* called under RCU protection or in contexts where
480 * mutex cannot be locked.
484 * Duplicate OPPs (both freq and volt are same) and opp->available
485 * -EEXIST Freq are same and volt are different OR
486 * Duplicate OPPs (both freq and volt are same) and !opp->available
487 * -ENOMEM Memory allocation failure
488 * -ENODEV when 'operating-points' property is not found or is invalid data
490 * -ENODATA when empty 'operating-points' property is found
491 * -EINVAL when invalid entries are found in opp-v2 table
493 int dev_pm_opp_of_add_table(struct device *dev)
495 struct device_node *opp_np;
499 * OPPs have two version of bindings now. The older one is deprecated,
500 * try for the new binding first.
502 opp_np = _of_get_opp_desc_node(dev);
505 * Try old-deprecated bindings for backward compatibility with
508 return _of_add_opp_table_v1(dev);
511 ret = _of_add_opp_table_v2(dev, opp_np);
516 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table);
518 /* CPU device specific helpers */
521 * dev_pm_opp_of_cpumask_remove_table() - Removes OPP table for @cpumask
522 * @cpumask: cpumask for which OPP table needs to be removed
524 * This removes the OPP tables for CPUs present in the @cpumask.
525 * This should be used only to remove static entries created from DT.
527 * Locking: The internal opp_table and opp structures are RCU protected.
528 * Hence this function internally uses RCU updater strategy with mutex locks
529 * to keep the integrity of the internal data structures. Callers should ensure
530 * that this function is *NOT* called under RCU protection or in contexts where
531 * mutex cannot be locked.
533 void dev_pm_opp_of_cpumask_remove_table(const struct cpumask *cpumask)
535 _dev_pm_opp_cpumask_remove_table(cpumask, true);
537 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_remove_table);
540 * dev_pm_opp_of_cpumask_add_table() - Adds OPP table for @cpumask
541 * @cpumask: cpumask for which OPP table needs to be added.
543 * This adds the OPP tables for CPUs present in the @cpumask.
545 * Locking: The internal opp_table and opp structures are RCU protected.
546 * Hence this function internally uses RCU updater strategy with mutex locks
547 * to keep the integrity of the internal data structures. Callers should ensure
548 * that this function is *NOT* called under RCU protection or in contexts where
549 * mutex cannot be locked.
551 int dev_pm_opp_of_cpumask_add_table(const struct cpumask *cpumask)
553 struct device *cpu_dev;
556 WARN_ON(cpumask_empty(cpumask));
558 for_each_cpu(cpu, cpumask) {
559 cpu_dev = get_cpu_device(cpu);
561 pr_err("%s: failed to get cpu%d device\n", __func__,
566 ret = dev_pm_opp_of_add_table(cpu_dev);
568 pr_err("%s: couldn't find opp table for cpu:%d, %d\n",
571 /* Free all other OPPs */
572 dev_pm_opp_of_cpumask_remove_table(cpumask);
579 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_add_table);
582 * Works only for OPP v2 bindings.
584 * Returns -ENOENT if operating-points-v2 bindings aren't supported.
587 * dev_pm_opp_of_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with
588 * @cpu_dev using operating-points-v2
591 * @cpu_dev: CPU device for which we do this operation
592 * @cpumask: cpumask to update with information of sharing CPUs
594 * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev.
596 * Returns -ENOENT if operating-points-v2 isn't present for @cpu_dev.
598 * Locking: The internal opp_table and opp structures are RCU protected.
599 * Hence this function internally uses RCU updater strategy with mutex locks
600 * to keep the integrity of the internal data structures. Callers should ensure
601 * that this function is *NOT* called under RCU protection or in contexts where
602 * mutex cannot be locked.
604 int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev,
605 struct cpumask *cpumask)
607 struct device_node *np, *tmp_np;
608 struct device *tcpu_dev;
611 /* Get OPP descriptor node */
612 np = _of_get_opp_desc_node(cpu_dev);
614 dev_dbg(cpu_dev, "%s: Couldn't find opp node.\n", __func__);
618 cpumask_set_cpu(cpu_dev->id, cpumask);
620 /* OPPs are shared ? */
621 if (!of_property_read_bool(np, "opp-shared"))
624 for_each_possible_cpu(cpu) {
625 if (cpu == cpu_dev->id)
628 tcpu_dev = get_cpu_device(cpu);
630 dev_err(cpu_dev, "%s: failed to get cpu%d device\n",
636 /* Get OPP descriptor node */
637 tmp_np = _of_get_opp_desc_node(tcpu_dev);
639 dev_err(tcpu_dev, "%s: Couldn't find opp node.\n",
645 /* CPUs are sharing opp node */
647 cpumask_set_cpu(cpu, cpumask);
656 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus);