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-rw-r--r--drivers/opp/cpu.c236
1 files changed, 236 insertions, 0 deletions
diff --git a/drivers/opp/cpu.c b/drivers/opp/cpu.c
new file mode 100644
index 000000000000..2d87bc1adf38
--- /dev/null
+++ b/drivers/opp/cpu.c
@@ -0,0 +1,236 @@
+/*
+ * 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/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 table 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.
+ */
+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;
+
+ max_opps = dev_pm_opp_get_opp_count(dev);
+ if (max_opps <= 0)
+ return max_opps ? max_opps : -ENODATA;
+
+ freq_table = kcalloc((max_opps + 1), sizeof(*freq_table), GFP_ATOMIC);
+ if (!freq_table)
+ return -ENOMEM;
+
+ 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;
+
+ dev_pm_opp_put(opp);
+ }
+
+ freq_table[i].driver_data = i;
+ freq_table[i].frequency = CPUFREQ_TABLE_END;
+
+ *table = &freq_table[0];
+
+out:
+ 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 */
+
+void _dev_pm_opp_cpumask_remove_table(const struct cpumask *cpumask, bool of)
+{
+ 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;
+ }
+
+ if (of)
+ dev_pm_opp_of_remove_table(cpu_dev);
+ else
+ dev_pm_opp_remove_table(cpu_dev);
+ }
+}
+
+/**
+ * dev_pm_opp_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 to remove all the OPPs entries associated with
+ * the cpus in @cpumask.
+ */
+void dev_pm_opp_cpumask_remove_table(const struct cpumask *cpumask)
+{
+ _dev_pm_opp_cpumask_remove_table(cpumask, false);
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_cpumask_remove_table);
+
+/**
+ * dev_pm_opp_set_sharing_cpus() - Mark OPP table as shared by few CPUs
+ * @cpu_dev: CPU device for which we do this operation
+ * @cpumask: cpumask of the CPUs which share the OPP table with @cpu_dev
+ *
+ * This marks OPP table of the @cpu_dev as shared by the CPUs present in
+ * @cpumask.
+ *
+ * Returns -ENODEV if OPP table isn't already present.
+ */
+int dev_pm_opp_set_sharing_cpus(struct device *cpu_dev,
+ const struct cpumask *cpumask)
+{
+ struct opp_device *opp_dev;
+ struct opp_table *opp_table;
+ struct device *dev;
+ int cpu, ret = 0;
+
+ opp_table = _find_opp_table(cpu_dev);
+ if (IS_ERR(opp_table))
+ return PTR_ERR(opp_table);
+
+ 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;
+ }
+
+ opp_dev = _add_opp_dev(dev, opp_table);
+ if (!opp_dev) {
+ dev_err(dev, "%s: failed to add opp-dev for cpu%d device\n",
+ __func__, cpu);
+ continue;
+ }
+
+ /* Mark opp-table as multiple CPUs are sharing it now */
+ opp_table->shared_opp = OPP_TABLE_ACCESS_SHARED;
+ }
+
+ dev_pm_opp_put_opp_table(opp_table);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_set_sharing_cpus);
+
+/**
+ * dev_pm_opp_get_sharing_cpus() - Get cpumask of CPUs sharing OPPs with @cpu_dev
+ * @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 -ENODEV if OPP table isn't already present and -EINVAL if the OPP
+ * table's status is access-unknown.
+ */
+int dev_pm_opp_get_sharing_cpus(struct device *cpu_dev, struct cpumask *cpumask)
+{
+ struct opp_device *opp_dev;
+ struct opp_table *opp_table;
+ int ret = 0;
+
+ opp_table = _find_opp_table(cpu_dev);
+ if (IS_ERR(opp_table))
+ return PTR_ERR(opp_table);
+
+ if (opp_table->shared_opp == OPP_TABLE_ACCESS_UNKNOWN) {
+ ret = -EINVAL;
+ goto put_opp_table;
+ }
+
+ cpumask_clear(cpumask);
+
+ if (opp_table->shared_opp == OPP_TABLE_ACCESS_SHARED) {
+ list_for_each_entry(opp_dev, &opp_table->dev_list, node)
+ cpumask_set_cpu(opp_dev->dev->id, cpumask);
+ } else {
+ cpumask_set_cpu(cpu_dev->id, cpumask);
+ }
+
+put_opp_table:
+ dev_pm_opp_put_opp_table(opp_table);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(dev_pm_opp_get_sharing_cpus);