4 files changed, 240 insertions, 2 deletions

diff --git a/kernel/Makefile b/kernel/Makefile
index eca595e2fd52..988cb3da7031 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -101,6 +101,7 @@ obj-$(CONFIG_RING_BUFFER) += trace/
 obj-$(CONFIG_TRACEPOINTS) += trace/
 obj-$(CONFIG_SMP) += sched_cpupri.o
 obj-$(CONFIG_IRQ_WORK) += irq_work.o
+obj-$(CONFIG_CPU_PM) += cpu_pm.o
 
 obj-$(CONFIG_PERF_EVENTS) += events/
 
diff --git a/kernel/cpu_pm.c b/kernel/cpu_pm.c
new file mode 100644
index 000000000000..249152e15308
--- /dev/null
+++ b/kernel/cpu_pm.c
@@ -0,0 +1,233 @@
+/*
+ * Copyright (C) 2011 Google, Inc.
+ *
+ * Author:
+ *      Colin Cross <ccross@android.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/cpu_pm.h>
+#include <linux/module.h>
+#include <linux/notifier.h>
+#include <linux/spinlock.h>
+#include <linux/syscore_ops.h>
+
+static DEFINE_RWLOCK(cpu_pm_notifier_lock);
+static RAW_NOTIFIER_HEAD(cpu_pm_notifier_chain);
+
+static int cpu_pm_notify(enum cpu_pm_event event, int nr_to_call, int *nr_calls)
+{
+        int ret;
+
+        ret = __raw_notifier_call_chain(&cpu_pm_notifier_chain, event, NULL,
+                nr_to_call, nr_calls);
+
+        return notifier_to_errno(ret);
+}
+
+/**
+ * cpu_pm_register_notifier - register a driver with cpu_pm
+ * @nb: notifier block to register
+ *
+ * Add a driver to a list of drivers that are notified about
+ * CPU and CPU cluster low power entry and exit.
+ *
+ * This function may sleep, and has the same return conditions as
+ * raw_notifier_chain_register.
+ */
+int cpu_pm_register_notifier(struct notifier_block *nb)
+{
+        unsigned long flags;
+        int ret;
+
+        write_lock_irqsave(&cpu_pm_notifier_lock, flags);
+        ret = raw_notifier_chain_register(&cpu_pm_notifier_chain, nb);
+        write_unlock_irqrestore(&cpu_pm_notifier_lock, flags);
+
+        return ret;
+}
+EXPORT_SYMBOL_GPL(cpu_pm_register_notifier);
+
+/**
+ * cpu_pm_unregister_notifier - unregister a driver with cpu_pm
+ * @nb: notifier block to be unregistered
+ *
+ * Remove a driver from the CPU PM notifier list.
+ *
+ * This function may sleep, and has the same return conditions as
+ * raw_notifier_chain_unregister.
+ */
+int cpu_pm_unregister_notifier(struct notifier_block *nb)
+{
+        unsigned long flags;
+        int ret;
+
+        write_lock_irqsave(&cpu_pm_notifier_lock, flags);
+        ret = raw_notifier_chain_unregister(&cpu_pm_notifier_chain, nb);
+        write_unlock_irqrestore(&cpu_pm_notifier_lock, flags);
+
+        return ret;
+}
+EXPORT_SYMBOL_GPL(cpu_pm_unregister_notifier);
+
+/**
+ * cpm_pm_enter - CPU low power entry notifier
+ *
+ * Notifies listeners that a single CPU is entering a low power state that may
+ * cause some blocks in the same power domain as the cpu to reset.
+ *
+ * Must be called on the affected CPU with interrupts disabled.  Platform is
+ * responsible for ensuring that cpu_pm_enter is not called twice on the same
+ * CPU before cpu_pm_exit is called. Notified drivers can include VFP
+ * co-processor, interrupt controller and it's PM extensions, local CPU
+ * timers context save/restore which shouldn't be interrupted. Hence it
+ * must be called with interrupts disabled.
+ *
+ * Return conditions are same as __raw_notifier_call_chain.
+ */
+int cpu_pm_enter(void)
+{
+        int nr_calls;
+        int ret = 0;
+
+        read_lock(&cpu_pm_notifier_lock);
+        ret = cpu_pm_notify(CPU_PM_ENTER, -1, &nr_calls);
+        if (ret)
+                /*
+                 * Inform listeners (nr_calls - 1) about failure of CPU PM
+                 * PM entry who are notified earlier to prepare for it.
+                 */
+                cpu_pm_notify(CPU_PM_ENTER_FAILED, nr_calls - 1, NULL);
+        read_unlock(&cpu_pm_notifier_lock);
+
+        return ret;
+}
+EXPORT_SYMBOL_GPL(cpu_pm_enter);
+
+/**
+ * cpm_pm_exit - CPU low power exit notifier
+ *
+ * Notifies listeners that a single CPU is exiting a low power state that may
+ * have caused some blocks in the same power domain as the cpu to reset.
+ *
+ * Notified drivers can include VFP co-processor, interrupt controller
+ * and it's PM extensions, local CPU timers context save/restore which
+ * shouldn't be interrupted. Hence it must be called with interrupts disabled.
+ *
+ * Return conditions are same as __raw_notifier_call_chain.
+ */
+int cpu_pm_exit(void)
+{
+        int ret;
+
+        read_lock(&cpu_pm_notifier_lock);
+        ret = cpu_pm_notify(CPU_PM_EXIT, -1, NULL);
+        read_unlock(&cpu_pm_notifier_lock);
+
+        return ret;
+}
+EXPORT_SYMBOL_GPL(cpu_pm_exit);
+
+/**
+ * cpm_cluster_pm_enter - CPU cluster low power entry notifier
+ *
+ * Notifies listeners that all cpus in a power domain are entering a low power
+ * state that may cause some blocks in the same power domain to reset.
+ *
+ * Must be called after cpu_pm_enter has been called on all cpus in the power
+ * domain, and before cpu_pm_exit has been called on any cpu in the power
+ * domain. Notified drivers can include VFP co-processor, interrupt controller
+ * and it's PM extensions, local CPU timers context save/restore which
+ * shouldn't be interrupted. Hence it must be called with interrupts disabled.
+ *
+ * Must be called with interrupts disabled.
+ *
+ * Return conditions are same as __raw_notifier_call_chain.
+ */
+int cpu_cluster_pm_enter(void)
+{
+        int nr_calls;
+        int ret = 0;
+
+        read_lock(&cpu_pm_notifier_lock);
+        ret = cpu_pm_notify(CPU_CLUSTER_PM_ENTER, -1, &nr_calls);
+        if (ret)
+                /*
+                 * Inform listeners (nr_calls - 1) about failure of CPU cluster
+                 * PM entry who are notified earlier to prepare for it.
+                 */
+                cpu_pm_notify(CPU_CLUSTER_PM_ENTER_FAILED, nr_calls - 1, NULL);
+        read_unlock(&cpu_pm_notifier_lock);
+
+        return ret;
+}
+EXPORT_SYMBOL_GPL(cpu_cluster_pm_enter);
+
+/**
+ * cpm_cluster_pm_exit - CPU cluster low power exit notifier
+ *
+ * Notifies listeners that all cpus in a power domain are exiting form a
+ * low power state that may have caused some blocks in the same power domain
+ * to reset.
+ *
+ * Must be called after cpu_pm_exit has been called on all cpus in the power
+ * domain, and before cpu_pm_exit has been called on any cpu in the power
+ * domain. Notified drivers can include VFP co-processor, interrupt controller
+ * and it's PM extensions, local CPU timers context save/restore which
+ * shouldn't be interrupted. Hence it must be called with interrupts disabled.
+ *
+ * Return conditions are same as __raw_notifier_call_chain.
+ */
+int cpu_cluster_pm_exit(void)
+{
+        int ret;
+
+        read_lock(&cpu_pm_notifier_lock);
+        ret = cpu_pm_notify(CPU_CLUSTER_PM_EXIT, -1, NULL);
+        read_unlock(&cpu_pm_notifier_lock);
+
+        return ret;
+}
+EXPORT_SYMBOL_GPL(cpu_cluster_pm_exit);
+
+#ifdef CONFIG_PM
+static int cpu_pm_suspend(void)
+{
+        int ret;
+
+        ret = cpu_pm_enter();
+        if (ret)
+                return ret;
+
+        ret = cpu_cluster_pm_enter();
+        return ret;
+}
+
+static void cpu_pm_resume(void)
+{
+        cpu_cluster_pm_exit();
+        cpu_pm_exit();
+}
+
+static struct syscore_ops cpu_pm_syscore_ops = {
+        .suspend = cpu_pm_suspend,
+        .resume = cpu_pm_resume,
+};
+
+static int cpu_pm_init(void)
+{
+        register_syscore_ops(&cpu_pm_syscore_ops);
+        return 0;
+}
+core_initcall(cpu_pm_init);
+#endif
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 0f857782d06f..fbe38f2e8edb 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -5758,6 +5758,7 @@ struct pmu *perf_init_event(struct perf_event *event)
         pmu = idr_find(&pmu_idr, event->attr.type);
         rcu_read_unlock();
         if (pmu) {
+                event->pmu = pmu;
                 ret = pmu->event_init(event);
                 if (ret)
                         pmu = ERR_PTR(ret);
@@ -5765,6 +5766,7 @@ struct pmu *perf_init_event(struct perf_event *event)
         }
 
         list_for_each_entry_rcu(pmu, &pmus, entry) {
+                event->pmu = pmu;
                 ret = pmu->event_init(event);
                 if (!ret)
                         goto unlock;
@@ -5891,8 +5893,6 @@ done:
                 return ERR_PTR(err);
         }
 
-        event->pmu = pmu;
-
         if (!event->parent) {
                 if (event->attach_state & PERF_ATTACH_TASK)
                         jump_label_inc(&perf_sched_events);
diff --git a/kernel/power/Kconfig b/kernel/power/Kconfig
index 3744c594b19b..80a85971cf64 100644
--- a/kernel/power/Kconfig
+++ b/kernel/power/Kconfig
@@ -235,3 +235,7 @@ config PM_GENERIC_DOMAINS
 config PM_GENERIC_DOMAINS_RUNTIME
         def_bool y
         depends on PM_RUNTIME && PM_GENERIC_DOMAINS
+
+config CPU_PM
+        bool
+        depends on SUSPEND || CPU_IDLE