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, *managed_table = NULL;
29 mutex_lock(&opp_table_lock);
31 list_for_each_entry_rcu(opp_table, &opp_tables, node) {
32 if (opp_table->np == np) {
34 * Multiple devices can point to the same OPP table and
35 * so will have same node-pointer, np.
37 * But the OPPs will be considered as shared only if the
38 * OPP table contains a "opp-shared" property.
40 if (opp_table->shared_opp == OPP_TABLE_ACCESS_SHARED) {
41 _get_opp_table_kref(opp_table);
42 managed_table = opp_table;
49 mutex_unlock(&opp_table_lock);
54 void _of_init_opp_table(struct opp_table *opp_table, struct device *dev)
56 struct device_node *np;
59 * Only required for backward compatibility with v1 bindings, but isn't
60 * harmful for other cases. And so we do it unconditionally.
62 np = of_node_get(dev->of_node);
66 if (!of_property_read_u32(np, "clock-latency", &val))
67 opp_table->clock_latency_ns_max = val;
68 of_property_read_u32(np, "voltage-tolerance",
69 &opp_table->voltage_tolerance_v1);
74 static bool _opp_is_supported(struct device *dev, struct opp_table *opp_table,
75 struct device_node *np)
77 unsigned int count = opp_table->supported_hw_count;
81 if (!opp_table->supported_hw) {
83 * In the case that no supported_hw has been set by the
84 * platform but there is an opp-supported-hw value set for
85 * an OPP then the OPP should not be enabled as there is
86 * no way to see if the hardware supports it.
88 if (of_find_property(np, "opp-supported-hw", NULL))
95 ret = of_property_read_u32_index(np, "opp-supported-hw", count,
98 dev_warn(dev, "%s: failed to read opp-supported-hw property at index %d: %d\n",
99 __func__, count, ret);
103 /* Both of these are bitwise masks of the versions */
104 if (!(version & opp_table->supported_hw[count]))
111 static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,
112 struct opp_table *opp_table)
114 u32 *microvolt, *microamp = NULL;
115 int supplies, vcount, icount, ret, i, j;
116 struct property *prop = NULL;
119 supplies = opp_table->regulator_count ? opp_table->regulator_count : 1;
121 /* Search for "opp-microvolt-<name>" */
122 if (opp_table->prop_name) {
123 snprintf(name, sizeof(name), "opp-microvolt-%s",
124 opp_table->prop_name);
125 prop = of_find_property(opp->np, name, NULL);
129 /* Search for "opp-microvolt" */
130 sprintf(name, "opp-microvolt");
131 prop = of_find_property(opp->np, name, NULL);
133 /* Missing property isn't a problem, but an invalid entry is */
138 vcount = of_property_count_u32_elems(opp->np, name);
140 dev_err(dev, "%s: Invalid %s property (%d)\n",
141 __func__, name, vcount);
145 /* There can be one or three elements per supply */
146 if (vcount != supplies && vcount != supplies * 3) {
147 dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
148 __func__, name, vcount, supplies);
152 microvolt = kmalloc_array(vcount, sizeof(*microvolt), GFP_KERNEL);
156 ret = of_property_read_u32_array(opp->np, name, microvolt, vcount);
158 dev_err(dev, "%s: error parsing %s: %d\n", __func__, name, ret);
163 /* Search for "opp-microamp-<name>" */
165 if (opp_table->prop_name) {
166 snprintf(name, sizeof(name), "opp-microamp-%s",
167 opp_table->prop_name);
168 prop = of_find_property(opp->np, name, NULL);
172 /* Search for "opp-microamp" */
173 sprintf(name, "opp-microamp");
174 prop = of_find_property(opp->np, name, NULL);
178 icount = of_property_count_u32_elems(opp->np, name);
180 dev_err(dev, "%s: Invalid %s property (%d)\n", __func__,
186 if (icount != supplies) {
187 dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
188 __func__, name, icount, supplies);
193 microamp = kmalloc_array(icount, sizeof(*microamp), GFP_KERNEL);
199 ret = of_property_read_u32_array(opp->np, name, microamp,
202 dev_err(dev, "%s: error parsing %s: %d\n", __func__,
209 for (i = 0, j = 0; i < supplies; i++) {
210 opp->supplies[i].u_volt = microvolt[j++];
212 if (vcount == supplies) {
213 opp->supplies[i].u_volt_min = opp->supplies[i].u_volt;
214 opp->supplies[i].u_volt_max = opp->supplies[i].u_volt;
216 opp->supplies[i].u_volt_min = microvolt[j++];
217 opp->supplies[i].u_volt_max = microvolt[j++];
221 opp->supplies[i].u_amp = microamp[i];
233 * dev_pm_opp_of_remove_table() - Free OPP table entries created from static DT
235 * @dev: device pointer used to lookup OPP table.
237 * Free OPPs created using static entries present in DT.
239 * Locking: The internal opp_table and opp structures are RCU protected.
240 * Hence this function indirectly uses RCU updater strategy with mutex locks
241 * to keep the integrity of the internal data structures. Callers should ensure
242 * that this function is *NOT* called under RCU protection or in contexts where
243 * mutex cannot be locked.
245 void dev_pm_opp_of_remove_table(struct device *dev)
247 _dev_pm_opp_find_and_remove_table(dev, false);
249 EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table);
251 /* Returns opp descriptor node for a device, caller must do of_node_put() */
252 static struct device_node *_of_get_opp_desc_node(struct device *dev)
255 * There should be only ONE phandle present in "operating-points-v2"
259 return of_parse_phandle(dev->of_node, "operating-points-v2", 0);
263 * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings)
264 * @opp_table: OPP table
265 * @dev: device for which we do this operation
268 * This function adds an opp definition to the opp table and returns status. The
269 * opp can be controlled using dev_pm_opp_enable/disable functions and may be
270 * removed by dev_pm_opp_remove.
272 * Locking: The internal opp_table and opp structures are RCU protected.
273 * Hence this function internally uses RCU updater strategy with mutex locks
274 * to keep the integrity of the internal data structures. Callers should ensure
275 * that this function is *NOT* called under RCU protection or in contexts where
276 * mutex cannot be locked.
280 * Duplicate OPPs (both freq and volt are same) and opp->available
281 * -EEXIST Freq are same and volt are different OR
282 * Duplicate OPPs (both freq and volt are same) and !opp->available
283 * -ENOMEM Memory allocation failure
284 * -EINVAL Failed parsing the OPP node
286 static int _opp_add_static_v2(struct opp_table *opp_table, struct device *dev,
287 struct device_node *np)
289 struct dev_pm_opp *new_opp;
294 new_opp = _opp_allocate(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 pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu\n",
353 __func__, new_opp->turbo, new_opp->rate,
354 new_opp->supplies[0].u_volt, new_opp->supplies[0].u_volt_min,
355 new_opp->supplies[0].u_volt_max, new_opp->clock_latency_ns);
358 * Notify the changes in the availability of the operable
359 * frequency/voltage list.
361 srcu_notifier_call_chain(&opp_table->srcu_head, OPP_EVENT_ADD, new_opp);
370 /* Initializes OPP tables based on new bindings */
371 static int _of_add_opp_table_v2(struct device *dev, struct device_node *opp_np)
373 struct device_node *np;
374 struct opp_table *opp_table;
375 int ret = 0, count = 0;
377 opp_table = _managed_opp(opp_np);
379 /* OPPs are already managed */
380 if (!_add_opp_dev(dev, opp_table))
385 opp_table = dev_pm_opp_get_opp_table(dev);
389 /* We have opp-table node now, iterate over it and add OPPs */
390 for_each_available_child_of_node(opp_np, np) {
393 ret = _opp_add_static_v2(opp_table, dev, np);
395 dev_err(dev, "%s: Failed to add OPP, %d\n", __func__,
397 _dev_pm_opp_remove_table(opp_table, dev, false);
402 /* There should be one of more OPP defined */
403 if (WARN_ON(!count)) {
408 opp_table->np = opp_np;
409 if (of_property_read_bool(opp_np, "opp-shared"))
410 opp_table->shared_opp = OPP_TABLE_ACCESS_SHARED;
412 opp_table->shared_opp = OPP_TABLE_ACCESS_EXCLUSIVE;
415 dev_pm_opp_put_opp_table(opp_table);
420 /* Initializes OPP tables based on old-deprecated bindings */
421 static int _of_add_opp_table_v1(struct device *dev)
423 struct opp_table *opp_table;
424 const struct property *prop;
428 prop = of_find_property(dev->of_node, "operating-points", NULL);
435 * Each OPP is a set of tuples consisting of frequency and
436 * voltage like <freq-kHz vol-uV>.
438 nr = prop->length / sizeof(u32);
440 dev_err(dev, "%s: Invalid OPP table\n", __func__);
444 opp_table = dev_pm_opp_get_opp_table(dev);
450 unsigned long freq = be32_to_cpup(val++) * 1000;
451 unsigned long volt = be32_to_cpup(val++);
453 ret = _opp_add_v1(opp_table, dev, freq, volt, false);
455 dev_err(dev, "%s: Failed to add OPP %ld (%d)\n",
456 __func__, freq, ret);
457 _dev_pm_opp_remove_table(opp_table, dev, false);
463 dev_pm_opp_put_opp_table(opp_table);
468 * dev_pm_opp_of_add_table() - Initialize opp table from device tree
469 * @dev: device pointer used to lookup OPP table.
471 * Register the initial OPP table with the OPP library for given device.
473 * Locking: The internal opp_table and opp structures are RCU protected.
474 * Hence this function indirectly uses RCU updater strategy with mutex locks
475 * to keep the integrity of the internal data structures. Callers should ensure
476 * that this function is *NOT* called under RCU protection or in contexts where
477 * mutex cannot be locked.
481 * Duplicate OPPs (both freq and volt are same) and opp->available
482 * -EEXIST Freq are same and volt are different OR
483 * Duplicate OPPs (both freq and volt are same) and !opp->available
484 * -ENOMEM Memory allocation failure
485 * -ENODEV when 'operating-points' property is not found or is invalid data
487 * -ENODATA when empty 'operating-points' property is found
488 * -EINVAL when invalid entries are found in opp-v2 table
490 int dev_pm_opp_of_add_table(struct device *dev)
492 struct device_node *opp_np;
496 * OPPs have two version of bindings now. The older one is deprecated,
497 * try for the new binding first.
499 opp_np = _of_get_opp_desc_node(dev);
502 * Try old-deprecated bindings for backward compatibility with
505 return _of_add_opp_table_v1(dev);
508 ret = _of_add_opp_table_v2(dev, opp_np);
513 EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table);
515 /* CPU device specific helpers */
518 * dev_pm_opp_of_cpumask_remove_table() - Removes OPP table for @cpumask
519 * @cpumask: cpumask for which OPP table needs to be removed
521 * This removes the OPP tables for CPUs present in the @cpumask.
522 * This should be used only to remove static entries created from DT.
524 * Locking: The internal opp_table and opp structures are RCU protected.
525 * Hence this function internally uses RCU updater strategy with mutex locks
526 * to keep the integrity of the internal data structures. Callers should ensure
527 * that this function is *NOT* called under RCU protection or in contexts where
528 * mutex cannot be locked.
530 void dev_pm_opp_of_cpumask_remove_table(const struct cpumask *cpumask)
532 _dev_pm_opp_cpumask_remove_table(cpumask, true);
534 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_remove_table);
537 * dev_pm_opp_of_cpumask_add_table() - Adds OPP table for @cpumask
538 * @cpumask: cpumask for which OPP table needs to be added.
540 * This adds the OPP tables for CPUs present in the @cpumask.
542 * Locking: The internal opp_table and opp structures are RCU protected.
543 * Hence this function internally uses RCU updater strategy with mutex locks
544 * to keep the integrity of the internal data structures. Callers should ensure
545 * that this function is *NOT* called under RCU protection or in contexts where
546 * mutex cannot be locked.
548 int dev_pm_opp_of_cpumask_add_table(const struct cpumask *cpumask)
550 struct device *cpu_dev;
553 WARN_ON(cpumask_empty(cpumask));
555 for_each_cpu(cpu, cpumask) {
556 cpu_dev = get_cpu_device(cpu);
558 pr_err("%s: failed to get cpu%d device\n", __func__,
563 ret = dev_pm_opp_of_add_table(cpu_dev);
565 pr_err("%s: couldn't find opp table for cpu:%d, %d\n",
568 /* Free all other OPPs */
569 dev_pm_opp_of_cpumask_remove_table(cpumask);
576 EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_add_table);
579 * Works only for OPP v2 bindings.
581 * Returns -ENOENT if operating-points-v2 bindings aren't supported.
584 * dev_pm_opp_of_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with
585 * @cpu_dev using operating-points-v2
588 * @cpu_dev: CPU device for which we do this operation
589 * @cpumask: cpumask to update with information of sharing CPUs
591 * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev.
593 * Returns -ENOENT if operating-points-v2 isn't present for @cpu_dev.
595 * Locking: The internal opp_table and opp structures are RCU protected.
596 * Hence this function internally uses RCU updater strategy with mutex locks
597 * to keep the integrity of the internal data structures. Callers should ensure
598 * that this function is *NOT* called under RCU protection or in contexts where
599 * mutex cannot be locked.
601 int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev,
602 struct cpumask *cpumask)
604 struct device_node *np, *tmp_np;
605 struct device *tcpu_dev;
608 /* Get OPP descriptor node */
609 np = _of_get_opp_desc_node(cpu_dev);
611 dev_dbg(cpu_dev, "%s: Couldn't find opp node.\n", __func__);
615 cpumask_set_cpu(cpu_dev->id, cpumask);
617 /* OPPs are shared ? */
618 if (!of_property_read_bool(np, "opp-shared"))
621 for_each_possible_cpu(cpu) {
622 if (cpu == cpu_dev->id)
625 tcpu_dev = get_cpu_device(cpu);
627 dev_err(cpu_dev, "%s: failed to get cpu%d device\n",
633 /* Get OPP descriptor node */
634 tmp_np = _of_get_opp_desc_node(tcpu_dev);
636 dev_err(tcpu_dev, "%s: Couldn't find opp node.\n",
642 /* CPUs are sharing opp node */
644 cpumask_set_cpu(cpu, cpumask);
653 EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus);