summaryrefslogtreecommitdiff
path: root/drivers/opp/of.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/opp/of.c')
-rw-r--r--drivers/opp/of.c633
1 files changed, 633 insertions, 0 deletions
diff --git a/drivers/opp/of.c b/drivers/opp/of.c
new file mode 100644
index 000000000000..0b718886479b
--- /dev/null
+++ b/drivers/opp/of.c
@@ -0,0 +1,633 @@
+/*
+ * Generic OPP OF helpers
+ *
+ * Copyright (C) 2009-2010 Texas Instruments Incorporated.
+ * Nishanth Menon
+ * Romit Dasgupta
+ * Kevin Hilman
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/cpu.h>
+#include <linux/errno.h>
+#include <linux/device.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+#include <linux/export.h>
+
+#include "opp.h"
+
+static struct opp_table *_managed_opp(const struct device_node *np)
+{
+ struct opp_table *opp_table, *managed_table = NULL;
+
+ mutex_lock(&opp_table_lock);
+
+ list_for_each_entry(opp_table, &opp_tables, node) {
+ if (opp_table->np == np) {
+ /*
+ * Multiple devices can point to the same OPP table and
+ * so will have same node-pointer, np.
+ *
+ * But the OPPs will be considered as shared only if the
+ * OPP table contains a "opp-shared" property.
+ */
+ if (opp_table->shared_opp == OPP_TABLE_ACCESS_SHARED) {
+ _get_opp_table_kref(opp_table);
+ managed_table = opp_table;
+ }
+
+ break;
+ }
+ }
+
+ mutex_unlock(&opp_table_lock);
+
+ return managed_table;
+}
+
+void _of_init_opp_table(struct opp_table *opp_table, struct device *dev)
+{
+ struct device_node *np;
+
+ /*
+ * Only required for backward compatibility with v1 bindings, but isn't
+ * harmful for other cases. And so we do it unconditionally.
+ */
+ np = of_node_get(dev->of_node);
+ if (np) {
+ u32 val;
+
+ if (!of_property_read_u32(np, "clock-latency", &val))
+ opp_table->clock_latency_ns_max = val;
+ of_property_read_u32(np, "voltage-tolerance",
+ &opp_table->voltage_tolerance_v1);
+ of_node_put(np);
+ }
+}
+
+static bool _opp_is_supported(struct device *dev, struct opp_table *opp_table,
+ struct device_node *np)
+{
+ unsigned int count = opp_table->supported_hw_count;
+ u32 version;
+ int ret;
+
+ if (!opp_table->supported_hw) {
+ /*
+ * In the case that no supported_hw has been set by the
+ * platform but there is an opp-supported-hw value set for
+ * an OPP then the OPP should not be enabled as there is
+ * no way to see if the hardware supports it.
+ */
+ if (of_find_property(np, "opp-supported-hw", NULL))
+ return false;
+ else
+ return true;
+ }
+
+ while (count--) {
+ ret = of_property_read_u32_index(np, "opp-supported-hw", count,
+ &version);
+ if (ret) {
+ dev_warn(dev, "%s: failed to read opp-supported-hw property at index %d: %d\n",
+ __func__, count, ret);
+ return false;
+ }
+
+ /* Both of these are bitwise masks of the versions */
+ if (!(version & opp_table->supported_hw[count]))
+ return false;
+ }
+
+ return true;
+}
+
+static int opp_parse_supplies(struct dev_pm_opp *opp, struct device *dev,
+ struct opp_table *opp_table)
+{
+ u32 *microvolt, *microamp = NULL;
+ int supplies, vcount, icount, ret, i, j;
+ struct property *prop = NULL;
+ char name[NAME_MAX];
+
+ supplies = opp_table->regulator_count ? opp_table->regulator_count : 1;
+
+ /* Search for "opp-microvolt-<name>" */
+ if (opp_table->prop_name) {
+ snprintf(name, sizeof(name), "opp-microvolt-%s",
+ opp_table->prop_name);
+ prop = of_find_property(opp->np, name, NULL);
+ }
+
+ if (!prop) {
+ /* Search for "opp-microvolt" */
+ sprintf(name, "opp-microvolt");
+ prop = of_find_property(opp->np, name, NULL);
+
+ /* Missing property isn't a problem, but an invalid entry is */
+ if (!prop) {
+ if (!opp_table->regulator_count)
+ return 0;
+
+ dev_err(dev, "%s: opp-microvolt missing although OPP managing regulators\n",
+ __func__);
+ return -EINVAL;
+ }
+ }
+
+ vcount = of_property_count_u32_elems(opp->np, name);
+ if (vcount < 0) {
+ dev_err(dev, "%s: Invalid %s property (%d)\n",
+ __func__, name, vcount);
+ return vcount;
+ }
+
+ /* There can be one or three elements per supply */
+ if (vcount != supplies && vcount != supplies * 3) {
+ dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
+ __func__, name, vcount, supplies);
+ return -EINVAL;
+ }
+
+ microvolt = kmalloc_array(vcount, sizeof(*microvolt), GFP_KERNEL);
+ if (!microvolt)
+ return -ENOMEM;
+
+ ret = of_property_read_u32_array(opp->np, name, microvolt, vcount);
+ if (ret) {
+ dev_err(dev, "%s: error parsing %s: %d\n", __func__, name, ret);
+ ret = -EINVAL;
+ goto free_microvolt;
+ }
+
+ /* Search for "opp-microamp-<name>" */
+ prop = NULL;
+ if (opp_table->prop_name) {
+ snprintf(name, sizeof(name), "opp-microamp-%s",
+ opp_table->prop_name);
+ prop = of_find_property(opp->np, name, NULL);
+ }
+
+ if (!prop) {
+ /* Search for "opp-microamp" */
+ sprintf(name, "opp-microamp");
+ prop = of_find_property(opp->np, name, NULL);
+ }
+
+ if (prop) {
+ icount = of_property_count_u32_elems(opp->np, name);
+ if (icount < 0) {
+ dev_err(dev, "%s: Invalid %s property (%d)\n", __func__,
+ name, icount);
+ ret = icount;
+ goto free_microvolt;
+ }
+
+ if (icount != supplies) {
+ dev_err(dev, "%s: Invalid number of elements in %s property (%d) with supplies (%d)\n",
+ __func__, name, icount, supplies);
+ ret = -EINVAL;
+ goto free_microvolt;
+ }
+
+ microamp = kmalloc_array(icount, sizeof(*microamp), GFP_KERNEL);
+ if (!microamp) {
+ ret = -EINVAL;
+ goto free_microvolt;
+ }
+
+ ret = of_property_read_u32_array(opp->np, name, microamp,
+ icount);
+ if (ret) {
+ dev_err(dev, "%s: error parsing %s: %d\n", __func__,
+ name, ret);
+ ret = -EINVAL;
+ goto free_microamp;
+ }
+ }
+
+ for (i = 0, j = 0; i < supplies; i++) {
+ opp->supplies[i].u_volt = microvolt[j++];
+
+ if (vcount == supplies) {
+ opp->supplies[i].u_volt_min = opp->supplies[i].u_volt;
+ opp->supplies[i].u_volt_max = opp->supplies[i].u_volt;
+ } else {
+ opp->supplies[i].u_volt_min = microvolt[j++];
+ opp->supplies[i].u_volt_max = microvolt[j++];
+ }
+
+ if (microamp)
+ opp->supplies[i].u_amp = microamp[i];
+ }
+
+free_microamp:
+ kfree(microamp);
+free_microvolt:
+ kfree(microvolt);
+
+ return ret;
+}
+
+/**
+ * dev_pm_opp_of_remove_table() - Free OPP table entries created from static DT
+ * entries
+ * @dev: device pointer used to lookup OPP table.
+ *
+ * Free OPPs created using static entries present in DT.
+ */
+void dev_pm_opp_of_remove_table(struct device *dev)
+{
+ _dev_pm_opp_find_and_remove_table(dev, false);
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_of_remove_table);
+
+/* Returns opp descriptor node for a device node, caller must
+ * do of_node_put() */
+static struct device_node *_opp_of_get_opp_desc_node(struct device_node *np)
+{
+ /*
+ * There should be only ONE phandle present in "operating-points-v2"
+ * property.
+ */
+
+ return of_parse_phandle(np, "operating-points-v2", 0);
+}
+
+/* Returns opp descriptor node for a device, caller must do of_node_put() */
+struct device_node *dev_pm_opp_of_get_opp_desc_node(struct device *dev)
+{
+ return _opp_of_get_opp_desc_node(dev->of_node);
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_opp_desc_node);
+
+/**
+ * _opp_add_static_v2() - Allocate static OPPs (As per 'v2' DT bindings)
+ * @opp_table: OPP table
+ * @dev: device for which we do this operation
+ * @np: device node
+ *
+ * This function adds an opp definition to the opp table and returns status. The
+ * opp can be controlled using dev_pm_opp_enable/disable functions and may be
+ * removed by dev_pm_opp_remove.
+ *
+ * Return:
+ * 0 On success OR
+ * Duplicate OPPs (both freq and volt are same) and opp->available
+ * -EEXIST Freq are same and volt are different OR
+ * Duplicate OPPs (both freq and volt are same) and !opp->available
+ * -ENOMEM Memory allocation failure
+ * -EINVAL Failed parsing the OPP node
+ */
+static int _opp_add_static_v2(struct opp_table *opp_table, struct device *dev,
+ struct device_node *np)
+{
+ struct dev_pm_opp *new_opp;
+ u64 rate;
+ u32 val;
+ int ret;
+
+ new_opp = _opp_allocate(opp_table);
+ if (!new_opp)
+ return -ENOMEM;
+
+ ret = of_property_read_u64(np, "opp-hz", &rate);
+ if (ret < 0) {
+ dev_err(dev, "%s: opp-hz not found\n", __func__);
+ goto free_opp;
+ }
+
+ /* Check if the OPP supports hardware's hierarchy of versions or not */
+ if (!_opp_is_supported(dev, opp_table, np)) {
+ dev_dbg(dev, "OPP not supported by hardware: %llu\n", rate);
+ goto free_opp;
+ }
+
+ /*
+ * Rate is defined as an unsigned long in clk API, and so casting
+ * explicitly to its type. Must be fixed once rate is 64 bit
+ * guaranteed in clk API.
+ */
+ new_opp->rate = (unsigned long)rate;
+ new_opp->turbo = of_property_read_bool(np, "turbo-mode");
+
+ new_opp->np = np;
+ new_opp->dynamic = false;
+ new_opp->available = true;
+
+ if (!of_property_read_u32(np, "clock-latency-ns", &val))
+ new_opp->clock_latency_ns = val;
+
+ ret = opp_parse_supplies(new_opp, dev, opp_table);
+ if (ret)
+ goto free_opp;
+
+ ret = _opp_add(dev, new_opp, opp_table);
+ if (ret) {
+ /* Don't return error for duplicate OPPs */
+ if (ret == -EBUSY)
+ ret = 0;
+ goto free_opp;
+ }
+
+ /* OPP to select on device suspend */
+ if (of_property_read_bool(np, "opp-suspend")) {
+ if (opp_table->suspend_opp) {
+ dev_warn(dev, "%s: Multiple suspend OPPs found (%lu %lu)\n",
+ __func__, opp_table->suspend_opp->rate,
+ new_opp->rate);
+ } else {
+ new_opp->suspend = true;
+ opp_table->suspend_opp = new_opp;
+ }
+ }
+
+ if (new_opp->clock_latency_ns > opp_table->clock_latency_ns_max)
+ opp_table->clock_latency_ns_max = new_opp->clock_latency_ns;
+
+ pr_debug("%s: turbo:%d rate:%lu uv:%lu uvmin:%lu uvmax:%lu latency:%lu\n",
+ __func__, new_opp->turbo, new_opp->rate,
+ new_opp->supplies[0].u_volt, new_opp->supplies[0].u_volt_min,
+ new_opp->supplies[0].u_volt_max, new_opp->clock_latency_ns);
+
+ /*
+ * Notify the changes in the availability of the operable
+ * frequency/voltage list.
+ */
+ blocking_notifier_call_chain(&opp_table->head, OPP_EVENT_ADD, new_opp);
+ return 0;
+
+free_opp:
+ _opp_free(new_opp);
+
+ return ret;
+}
+
+/* Initializes OPP tables based on new bindings */
+static int _of_add_opp_table_v2(struct device *dev, struct device_node *opp_np)
+{
+ struct device_node *np;
+ struct opp_table *opp_table;
+ int ret = 0, count = 0;
+
+ opp_table = _managed_opp(opp_np);
+ if (opp_table) {
+ /* OPPs are already managed */
+ if (!_add_opp_dev(dev, opp_table))
+ ret = -ENOMEM;
+ goto put_opp_table;
+ }
+
+ opp_table = dev_pm_opp_get_opp_table(dev);
+ if (!opp_table)
+ return -ENOMEM;
+
+ /* We have opp-table node now, iterate over it and add OPPs */
+ for_each_available_child_of_node(opp_np, np) {
+ count++;
+
+ ret = _opp_add_static_v2(opp_table, dev, np);
+ if (ret) {
+ dev_err(dev, "%s: Failed to add OPP, %d\n", __func__,
+ ret);
+ _dev_pm_opp_remove_table(opp_table, dev, false);
+ goto put_opp_table;
+ }
+ }
+
+ /* There should be one of more OPP defined */
+ if (WARN_ON(!count)) {
+ ret = -ENOENT;
+ goto put_opp_table;
+ }
+
+ opp_table->np = opp_np;
+ if (of_property_read_bool(opp_np, "opp-shared"))
+ opp_table->shared_opp = OPP_TABLE_ACCESS_SHARED;
+ else
+ opp_table->shared_opp = OPP_TABLE_ACCESS_EXCLUSIVE;
+
+put_opp_table:
+ dev_pm_opp_put_opp_table(opp_table);
+
+ return ret;
+}
+
+/* Initializes OPP tables based on old-deprecated bindings */
+static int _of_add_opp_table_v1(struct device *dev)
+{
+ struct opp_table *opp_table;
+ const struct property *prop;
+ const __be32 *val;
+ int nr, ret = 0;
+
+ prop = of_find_property(dev->of_node, "operating-points", NULL);
+ if (!prop)
+ return -ENODEV;
+ if (!prop->value)
+ return -ENODATA;
+
+ /*
+ * Each OPP is a set of tuples consisting of frequency and
+ * voltage like <freq-kHz vol-uV>.
+ */
+ nr = prop->length / sizeof(u32);
+ if (nr % 2) {
+ dev_err(dev, "%s: Invalid OPP table\n", __func__);
+ return -EINVAL;
+ }
+
+ opp_table = dev_pm_opp_get_opp_table(dev);
+ if (!opp_table)
+ return -ENOMEM;
+
+ val = prop->value;
+ while (nr) {
+ unsigned long freq = be32_to_cpup(val++) * 1000;
+ unsigned long volt = be32_to_cpup(val++);
+
+ ret = _opp_add_v1(opp_table, dev, freq, volt, false);
+ if (ret) {
+ dev_err(dev, "%s: Failed to add OPP %ld (%d)\n",
+ __func__, freq, ret);
+ _dev_pm_opp_remove_table(opp_table, dev, false);
+ break;
+ }
+ nr -= 2;
+ }
+
+ dev_pm_opp_put_opp_table(opp_table);
+ return ret;
+}
+
+/**
+ * dev_pm_opp_of_add_table() - Initialize opp table from device tree
+ * @dev: device pointer used to lookup OPP table.
+ *
+ * Register the initial OPP table with the OPP library for given device.
+ *
+ * Return:
+ * 0 On success OR
+ * Duplicate OPPs (both freq and volt are same) and opp->available
+ * -EEXIST Freq are same and volt are different OR
+ * Duplicate OPPs (both freq and volt are same) and !opp->available
+ * -ENOMEM Memory allocation failure
+ * -ENODEV when 'operating-points' property is not found or is invalid data
+ * in device node.
+ * -ENODATA when empty 'operating-points' property is found
+ * -EINVAL when invalid entries are found in opp-v2 table
+ */
+int dev_pm_opp_of_add_table(struct device *dev)
+{
+ struct device_node *opp_np;
+ int ret;
+
+ /*
+ * OPPs have two version of bindings now. The older one is deprecated,
+ * try for the new binding first.
+ */
+ opp_np = dev_pm_opp_of_get_opp_desc_node(dev);
+ if (!opp_np) {
+ /*
+ * Try old-deprecated bindings for backward compatibility with
+ * older dtbs.
+ */
+ return _of_add_opp_table_v1(dev);
+ }
+
+ ret = _of_add_opp_table_v2(dev, opp_np);
+ of_node_put(opp_np);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_of_add_table);
+
+/* CPU device specific helpers */
+
+/**
+ * dev_pm_opp_of_cpumask_remove_table() - Removes OPP table for @cpumask
+ * @cpumask: cpumask for which OPP table needs to be removed
+ *
+ * This removes the OPP tables for CPUs present in the @cpumask.
+ * This should be used only to remove static entries created from DT.
+ */
+void dev_pm_opp_of_cpumask_remove_table(const struct cpumask *cpumask)
+{
+ _dev_pm_opp_cpumask_remove_table(cpumask, true);
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_remove_table);
+
+/**
+ * dev_pm_opp_of_cpumask_add_table() - Adds OPP table for @cpumask
+ * @cpumask: cpumask for which OPP table needs to be added.
+ *
+ * This adds the OPP tables for CPUs present in the @cpumask.
+ */
+int dev_pm_opp_of_cpumask_add_table(const struct cpumask *cpumask)
+{
+ struct device *cpu_dev;
+ int cpu, ret = 0;
+
+ WARN_ON(cpumask_empty(cpumask));
+
+ for_each_cpu(cpu, cpumask) {
+ cpu_dev = get_cpu_device(cpu);
+ if (!cpu_dev) {
+ pr_err("%s: failed to get cpu%d device\n", __func__,
+ cpu);
+ continue;
+ }
+
+ ret = dev_pm_opp_of_add_table(cpu_dev);
+ if (ret) {
+ /*
+ * OPP may get registered dynamically, don't print error
+ * message here.
+ */
+ pr_debug("%s: couldn't find opp table for cpu:%d, %d\n",
+ __func__, cpu, ret);
+
+ /* Free all other OPPs */
+ dev_pm_opp_of_cpumask_remove_table(cpumask);
+ break;
+ }
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_add_table);
+
+/*
+ * Works only for OPP v2 bindings.
+ *
+ * Returns -ENOENT if operating-points-v2 bindings aren't supported.
+ */
+/**
+ * dev_pm_opp_of_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with
+ * @cpu_dev using operating-points-v2
+ * bindings.
+ *
+ * @cpu_dev: CPU device for which we do this operation
+ * @cpumask: cpumask to update with information of sharing CPUs
+ *
+ * This updates the @cpumask with CPUs that are sharing OPPs with @cpu_dev.
+ *
+ * Returns -ENOENT if operating-points-v2 isn't present for @cpu_dev.
+ */
+int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev,
+ struct cpumask *cpumask)
+{
+ struct device_node *np, *tmp_np, *cpu_np;
+ int cpu, ret = 0;
+
+ /* Get OPP descriptor node */
+ np = dev_pm_opp_of_get_opp_desc_node(cpu_dev);
+ if (!np) {
+ dev_dbg(cpu_dev, "%s: Couldn't find opp node.\n", __func__);
+ return -ENOENT;
+ }
+
+ cpumask_set_cpu(cpu_dev->id, cpumask);
+
+ /* OPPs are shared ? */
+ if (!of_property_read_bool(np, "opp-shared"))
+ goto put_cpu_node;
+
+ for_each_possible_cpu(cpu) {
+ if (cpu == cpu_dev->id)
+ continue;
+
+ cpu_np = of_get_cpu_node(cpu, NULL);
+ if (!cpu_np) {
+ dev_err(cpu_dev, "%s: failed to get cpu%d node\n",
+ __func__, cpu);
+ ret = -ENOENT;
+ goto put_cpu_node;
+ }
+
+ /* Get OPP descriptor node */
+ tmp_np = _opp_of_get_opp_desc_node(cpu_np);
+ if (!tmp_np) {
+ pr_err("%pOF: Couldn't find opp node\n", cpu_np);
+ ret = -ENOENT;
+ goto put_cpu_node;
+ }
+
+ /* CPUs are sharing opp node */
+ if (np == tmp_np)
+ cpumask_set_cpu(cpu, cpumask);
+
+ of_node_put(tmp_np);
+ }
+
+put_cpu_node:
+ of_node_put(np);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus);
generated by cgit v1.2.3-58-ga151 (git 2.39.0) at 2024-12-21 00:18:46 +0000