]> asedeno.scripts.mit.edu Git - linux.git/blobdiff - drivers/base/power/opp/cpu.c
Merge remote-tracking branches 'spi/topic/spidev', 'spi/topic/sunxi', 'spi/topic...
[linux.git] / drivers / base / power / opp / cpu.c
index ba2bdbd932ef3c1ebaff47c6203bddb27fe9c03b..8c3434bdb26dee8c23a637798b18a3963666ee70 100644 (file)
@@ -18,7 +18,6 @@
 #include <linux/err.h>
 #include <linux/errno.h>
 #include <linux/export.h>
-#include <linux/of.h>
 #include <linux/slab.h>
 
 #include "opp.h"
@@ -119,8 +118,66 @@ void dev_pm_opp_free_cpufreq_table(struct device *dev,
 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)
+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.
+ *
+ * Locking: The internal opp_table and opp structures are RCU protected.
+ * Hence this function internally uses RCU updater strategy with mutex locks
+ * to keep the integrity of the internal data structures. Callers should ensure
+ * that this function is *NOT* called under RCU protection or in contexts where
+ * mutex cannot be locked.
+ */
+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.
+ *
+ * Locking: The internal opp_table and opp structures are RCU protected.
+ * Hence this function internally uses RCU updater strategy with mutex locks
+ * to keep the integrity of the internal data structures. Callers should ensure
+ * that this function is *NOT* called under RCU protection or in contexts where
+ * mutex cannot be locked.
+ */
+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;
@@ -131,7 +188,7 @@ int dev_pm_opp_set_sharing_cpus(struct device *cpu_dev, cpumask_var_t cpumask)
 
        opp_table = _find_opp_table(cpu_dev);
        if (IS_ERR(opp_table)) {
-               ret = -EINVAL;
+               ret = PTR_ERR(opp_table);
                goto unlock;
        }
 
@@ -152,6 +209,9 @@ int dev_pm_opp_set_sharing_cpus(struct device *cpu_dev, cpumask_var_t cpumask)
                                __func__, cpu);
                        continue;
                }
+
+               /* Mark opp-table as multiple CPUs are sharing it now */
+               opp_table->shared_opp = OPP_TABLE_ACCESS_SHARED;
        }
 unlock:
        mutex_unlock(&opp_table_lock);
@@ -160,112 +220,53 @@ int dev_pm_opp_set_sharing_cpus(struct device *cpu_dev, cpumask_var_t cpumask)
 }
 EXPORT_SYMBOL_GPL(dev_pm_opp_set_sharing_cpus);
 
-#ifdef CONFIG_OF
-void dev_pm_opp_of_cpumask_remove_table(cpumask_var_t cpumask)
+/**
+ * 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.
+ *
+ * Locking: The internal opp_table and opp structures are RCU protected.
+ * Hence this function internally uses RCU updater strategy with mutex locks
+ * to keep the integrity of the internal data structures. Callers should ensure
+ * that this function is *NOT* called under RCU protection or in contexts where
+ * mutex cannot be locked.
+ */
+int dev_pm_opp_get_sharing_cpus(struct device *cpu_dev, struct cpumask *cpumask)
 {
-       struct device *cpu_dev;
-       int cpu;
-
-       WARN_ON(cpumask_empty(cpumask));
+       struct opp_device *opp_dev;
+       struct opp_table *opp_table;
+       int ret = 0;
 
-       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;
-               }
+       mutex_lock(&opp_table_lock);
 
-               dev_pm_opp_of_remove_table(cpu_dev);
+       opp_table = _find_opp_table(cpu_dev);
+       if (IS_ERR(opp_table)) {
+               ret = PTR_ERR(opp_table);
+               goto unlock;
        }
-}
-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;
-               }
+       if (opp_table->shared_opp == OPP_TABLE_ACCESS_UNKNOWN) {
+               ret = -EINVAL;
+               goto unlock;
        }
 
-       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.
- */
-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;
+       cpumask_clear(cpumask);
 
-       /* 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;
+       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);
        }
 
-       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;
-
-               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);
-       }
+unlock:
+       mutex_unlock(&opp_table_lock);
 
-put_cpu_node:
-       of_node_put(np);
        return ret;
 }
-EXPORT_SYMBOL_GPL(dev_pm_opp_of_get_sharing_cpus);
-#endif
+EXPORT_SYMBOL_GPL(dev_pm_opp_get_sharing_cpus);