--- /dev/null
+/*
+ * Generic OPP helper interface for CPU device
+ *
+ * Copyright (C) 2009-2014 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/cpufreq.h>
+#include <linux/err.h>
+#include <linux/errno.h>
+#include <linux/export.h>
+#include <linux/of.h>
+#include <linux/slab.h>
+
+#include "opp.h"
+
+#ifdef CONFIG_CPU_FREQ
+
+/**
+ * dev_pm_opp_init_cpufreq_table() - create a cpufreq table for a device
+ * @dev: device for which we do this operation
+ * @table: Cpufreq table returned back to caller
+ *
+ * Generate a cpufreq table for a provided device- this assumes that the
+ * opp list is already initialized and ready for usage.
+ *
+ * This function allocates required memory for the cpufreq table. It is
+ * expected that the caller does the required maintenance such as freeing
+ * the table as required.
+ *
+ * Returns -EINVAL for bad pointers, -ENODEV if the device is not found, -ENOMEM
+ * if no memory available for the operation (table is not populated), returns 0
+ * if successful and table is populated.
+ *
+ * WARNING: It is important for the callers to ensure refreshing their copy of
+ * the table if any of the mentioned functions have been invoked in the interim.
+ *
+ * Locking: The internal device_opp and opp structures are RCU protected.
+ * Since we just use the regular accessor functions to access the internal data
+ * structures, we use RCU read lock inside this function. As a result, users of
+ * this function DONOT need to use explicit locks for invoking.
+ */
+int dev_pm_opp_init_cpufreq_table(struct device *dev,
+ struct cpufreq_frequency_table **table)
+{
+ struct dev_pm_opp *opp;
+ struct cpufreq_frequency_table *freq_table = NULL;
+ int i, max_opps, ret = 0;
+ unsigned long rate;
+
+ rcu_read_lock();
+
+ max_opps = dev_pm_opp_get_opp_count(dev);
+ if (max_opps <= 0) {
+ ret = max_opps ? max_opps : -ENODATA;
+ goto out;
+ }
+
+ freq_table = kcalloc((max_opps + 1), sizeof(*freq_table), GFP_ATOMIC);
+ if (!freq_table) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ for (i = 0, rate = 0; i < max_opps; i++, rate++) {
+ /* find next rate */
+ opp = dev_pm_opp_find_freq_ceil(dev, &rate);
+ if (IS_ERR(opp)) {
+ ret = PTR_ERR(opp);
+ goto out;
+ }
+ freq_table[i].driver_data = i;
+ freq_table[i].frequency = rate / 1000;
+
+ /* Is Boost/turbo opp ? */
+ if (dev_pm_opp_is_turbo(opp))
+ freq_table[i].flags = CPUFREQ_BOOST_FREQ;
+ }
+
+ freq_table[i].driver_data = i;
+ freq_table[i].frequency = CPUFREQ_TABLE_END;
+
+ *table = &freq_table[0];
+
+out:
+ rcu_read_unlock();
+ if (ret)
+ kfree(freq_table);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_init_cpufreq_table);
+
+/**
+ * dev_pm_opp_free_cpufreq_table() - free the cpufreq table
+ * @dev: device for which we do this operation
+ * @table: table to free
+ *
+ * Free up the table allocated by dev_pm_opp_init_cpufreq_table
+ */
+void dev_pm_opp_free_cpufreq_table(struct device *dev,
+ struct cpufreq_frequency_table **table)
+{
+ if (!table)
+ return;
+
+ kfree(*table);
+ *table = NULL;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_free_cpufreq_table);
+#endif /* CONFIG_CPU_FREQ */
+
+/* Required only for V1 bindings, as v2 can manage it from DT itself */
+int dev_pm_opp_set_sharing_cpus(struct device *cpu_dev, cpumask_var_t cpumask)
+{
+ struct device_list_opp *list_dev;
+ struct device_opp *dev_opp;
+ struct device *dev;
+ int cpu, ret = 0;
+
+ mutex_lock(&dev_opp_list_lock);
+
+ dev_opp = _find_device_opp(cpu_dev);
+ if (IS_ERR(dev_opp)) {
+ ret = -EINVAL;
+ goto unlock;
+ }
+
+ for_each_cpu(cpu, cpumask) {
+ if (cpu == cpu_dev->id)
+ continue;
+
+ dev = get_cpu_device(cpu);
+ if (!dev) {
+ dev_err(cpu_dev, "%s: failed to get cpu%d device\n",
+ __func__, cpu);
+ continue;
+ }
+
+ list_dev = _add_list_dev(dev, dev_opp);
+ if (!list_dev) {
+ dev_err(dev, "%s: failed to add list-dev for cpu%d device\n",
+ __func__, cpu);
+ continue;
+ }
+ }
+unlock:
+ mutex_unlock(&dev_opp_list_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_set_sharing_cpus);
+
+#ifdef CONFIG_OF
+void dev_pm_opp_of_cpumask_remove_table(cpumask_var_t cpumask)
+{
+ struct device *cpu_dev;
+ int cpu;
+
+ 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;
+ }
+
+ dev_pm_opp_of_remove_table(cpu_dev);
+ }
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_of_cpumask_remove_table);
+
+int dev_pm_opp_of_cpumask_add_table(cpumask_var_t 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) {
+ pr_err("%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.
+ *
+ * cpumask should be already set to mask of cpu_dev->id.
+ * Returns -ENOENT if operating-points-v2 bindings aren't supported.
+ */
+int dev_pm_opp_of_get_sharing_cpus(struct device *cpu_dev, cpumask_var_t cpumask)
+{
+ struct device_node *np, *tmp_np;
+ struct device *tcpu_dev;
+ int cpu, ret = 0;
+
+ /* Get OPP descriptor node */
+ np = _of_get_opp_desc_node(cpu_dev);
+ if (!np) {
+ dev_dbg(cpu_dev, "%s: Couldn't find cpu_dev node.\n", __func__);
+ return -ENOENT;
+ }
+
+ /* 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;
+
+ tcpu_dev = get_cpu_device(cpu);
+ if (!tcpu_dev) {
+ dev_err(cpu_dev, "%s: failed to get cpu%d device\n",
+ __func__, cpu);
+ ret = -ENODEV;
+ goto put_cpu_node;
+ }
+
+ /* Get OPP descriptor node */
+ tmp_np = _of_get_opp_desc_node(tcpu_dev);
+ if (!tmp_np) {
+ dev_err(tcpu_dev, "%s: Couldn't find tcpu_dev node.\n",
+ __func__);
+ 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);
+#endif
Code Review / kvmfornfv.git / blobdiff