Merge branch 'develop-3.0-rk30' of ssh://10.10.10.29/rk/kernel into develop-3.0-rk30

arch/arm/Kconfig

@@ -29,6 +29,7 @@ config ARM
 	select HAVE_GENERIC_HARDIRQS
 	select HAVE_SPARSE_IRQ
 	select GENERIC_IRQ_SHOW
+	select CPU_PM if (SUSPEND || CPU_IDLE)
 	help
 	  The ARM series is a line of low-power-consumption RISC chip designs
 	  licensed by ARM Ltd and targeted at embedded applications and

arch/arm/include/asm/proc-fns.h

@@ -97,8 +97,22 @@ extern void cpu_resume(void);
 
 #ifdef CONFIG_MMU
 
+#ifdef CONFIG_SMP
+
+#define cpu_switch_mm(pgd, mm)	\
+	({							\
+		unsigned long flags;				\
+		local_irq_save(flags);				\
+		cpu_do_switch_mm(virt_to_phys(pgd), mm);	\
+		local_irq_restore(flags);			\
+	})
+
+#else /* SMP */
+
 #define cpu_switch_mm(pgd,mm) cpu_do_switch_mm(virt_to_phys(pgd),mm)
 
+#endif
+
 #define cpu_get_pgd()	\
 	({						\
 		unsigned long pg;			\

arch/arm/kernel/smp_twd.c

@@ -10,13 +10,17 @@
  */
 #include <linux/init.h>
 #include <linux/kernel.h>
+#include <linux/clk.h>
+#include <linux/cpufreq.h>
 #include <linux/delay.h>
 #include <linux/device.h>
+#include <linux/err.h>
 #include <linux/smp.h>
 #include <linux/jiffies.h>
 #include <linux/clockchips.h>
 #include <linux/irq.h>
 #include <linux/io.h>
+#include <linux/percpu.h>
 
 #include <asm/smp_twd.h>
 #include <asm/hardware/gic.h>
@@ -24,7 +28,9 @@
 /* set up by the platform code */
 void __iomem *twd_base;
 
+static struct clk *twd_clk;
 static unsigned long twd_timer_rate;
+static DEFINE_PER_CPU(struct clock_event_device *, twd_ce);
 
 static void twd_set_mode(enum clock_event_mode mode,
 			struct clock_event_device *clk)
@@ -80,6 +86,48 @@ int twd_timer_ack(void)
 	return 0;
 }
 
+/*
+ * Updates clockevent frequency when the cpu frequency changes.
+ * Called on the cpu that is changing frequency with interrupts disabled.
+ */
+static void twd_update_frequency(void *data)
+{
+	twd_timer_rate = clk_get_rate(twd_clk);
+
+	clockevents_update_freq(__get_cpu_var(twd_ce), twd_timer_rate);
+}
+
+static int twd_cpufreq_transition(struct notifier_block *nb,
+	unsigned long state, void *data)
+{
+	struct cpufreq_freqs *freqs = data;
+
+	/*
+	 * The twd clock events must be reprogrammed to account for the new
+	 * frequency.  The timer is local to a cpu, so cross-call to the
+	 * changing cpu.
+	 */
+	if (state == CPUFREQ_POSTCHANGE || state == CPUFREQ_RESUMECHANGE)
+		smp_call_function_single(freqs->cpu, twd_update_frequency,
+			NULL, 1);
+
+	return NOTIFY_OK;
+}
+
+static struct notifier_block twd_cpufreq_nb = {
+	.notifier_call = twd_cpufreq_transition,
+};
+
+static int twd_cpufreq_init(void)
+{
+	if (!IS_ERR_OR_NULL(twd_clk))
+		return cpufreq_register_notifier(&twd_cpufreq_nb,
+			CPUFREQ_TRANSITION_NOTIFIER);
+
+	return 0;
+}
+core_initcall(twd_cpufreq_init);
+
 static void __cpuinit twd_calibrate_rate(void)
 {
 	unsigned long count;
@@ -124,7 +172,18 @@ static void __cpuinit twd_calibrate_rate(void)
  */
 void __cpuinit twd_timer_setup(struct clock_event_device *clk)
 {
-	twd_calibrate_rate();
+	if (twd_clk == NULL) {
+		twd_clk = clk_get_sys("smp_twd", NULL);
+		if (IS_ERR_OR_NULL(twd_clk))
+			pr_warn("%s: no clock found\n", __func__);
+	}
+
+	if (!IS_ERR_OR_NULL(twd_clk))
+		twd_timer_rate = clk_get_rate(twd_clk);
+	else
+		twd_calibrate_rate();
+
+	__raw_writel(0, twd_base + TWD_TIMER_CONTROL);
 
 	clk->name = "local_timer";
 	clk->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT |
@@ -132,13 +191,11 @@ void __cpuinit twd_timer_setup(struct clock_event_device *clk)
 	clk->rating = 350;
 	clk->set_mode = twd_set_mode;
 	clk->set_next_event = twd_set_next_event;
-	clk->shift = 20;
-	clk->mult = div_sc(twd_timer_rate, NSEC_PER_SEC, clk->shift);
-	clk->max_delta_ns = clockevent_delta2ns(0xffffffff, clk);
-	clk->min_delta_ns = clockevent_delta2ns(0xf, clk);
+
+	__get_cpu_var(twd_ce) = clk;
+
+	clockevents_config_and_register(clk, twd_timer_rate, 0xf, 0xffffffff);
 
 	/* Make sure our local interrupt controller has this enabled */
 	gic_enable_ppi(clk->irq);
-
-	clockevents_register_device(clk);
 }

arch/arm/mm/context.c

@@ -99,8 +99,7 @@ static void reset_context(void *info)
 	set_mm_context(mm, asid);
 
 	/* set the new ASID */
-	asm("mcr	p15, 0, %0, c13, c0, 1\n" : : "r" (mm->context.id));
-	isb();
+	cpu_switch_mm(mm->pgd, mm);
 }
 
 #else

arch/arm/vfp/vfpmodule.c

@@ -11,6 +11,7 @@
 #include <linux/module.h>
 #include <linux/types.h>
 #include <linux/cpu.h>
+#include <linux/cpu_pm.h>
 #include <linux/kernel.h>
 #include <linux/notifier.h>
 #include <linux/signal.h>
@@ -403,9 +404,7 @@ static void vfp_enable(void *unused)
 	set_copro_access(access | CPACC_FULL(10) | CPACC_FULL(11));
 }
 
-#ifdef CONFIG_PM
-#include <linux/syscore_ops.h>
-
+#ifdef CONFIG_CPU_PM
 static int vfp_pm_suspend(void)
 {
 	struct thread_info *ti = current_thread_info();
@@ -439,19 +438,33 @@ static void vfp_pm_resume(void)
 	fmxr(FPEXC, fmrx(FPEXC) & ~FPEXC_EN);
 }
 
-static struct syscore_ops vfp_pm_syscore_ops = {
-	.suspend	= vfp_pm_suspend,
-	.resume		= vfp_pm_resume,
+static int vfp_cpu_pm_notifier(struct notifier_block *self, unsigned long cmd,
+	void *v)
+{
+	switch (cmd) {
+	case CPU_PM_ENTER:
+		vfp_pm_suspend();
+		break;
+	case CPU_PM_ENTER_FAILED:
+	case CPU_PM_EXIT:
+		vfp_pm_resume();
+		break;
+	}
+	return NOTIFY_OK;
+}
+
+static struct notifier_block vfp_cpu_pm_notifier_block = {
+	.notifier_call = vfp_cpu_pm_notifier,
 };
 
 static void vfp_pm_init(void)
 {
-	register_syscore_ops(&vfp_pm_syscore_ops);
+	cpu_pm_register_notifier(&vfp_cpu_pm_notifier_block);
 }
 
 #else
 static inline void vfp_pm_init(void) { }
-#endif /* CONFIG_PM */
+#endif /* CONFIG_CPU_PM */
 
 void vfp_sync_hwstate(struct thread_info *thread)
 {

include/linux/cpu_pm.h

@@ -0,0 +1,109 @@
+/*
+ * 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.
+ *
+ */
+
+#ifndef _LINUX_CPU_PM_H
+#define _LINUX_CPU_PM_H
+
+#include <linux/kernel.h>
+#include <linux/notifier.h>
+
+/*
+ * When a CPU goes to a low power state that turns off power to the CPU's
+ * power domain, the contents of some blocks (floating point coprocessors,
+ * interrupt controllers, caches, timers) in the same power domain can
+ * be lost.  The cpm_pm notifiers provide a method for platform idle, suspend,
+ * and hotplug implementations to notify the drivers for these blocks that
+ * they may be reset.
+ *
+ * All cpu_pm notifications must be called with interrupts disabled.
+ *
+ * The notifications are split into two classes: CPU notifications and CPU
+ * cluster notifications.
+ *
+ * CPU notifications apply to a single CPU and must be called on the affected
+ * CPU.  They are used to save per-cpu context for affected blocks.
+ *
+ * CPU cluster notifications apply to all CPUs in a single power domain. They
+ * are used to save any global context for affected blocks, and must be called
+ * after all the CPUs in the power domain have been notified of the low power
+ * state.
+ */
+
+/*
+ * Event codes passed as unsigned long val to notifier calls
+ */
+enum cpu_pm_event {
+	/* A single cpu is entering a low power state */
+	CPU_PM_ENTER,
+
+	/* A single cpu failed to enter a low power state */
+	CPU_PM_ENTER_FAILED,
+
+	/* A single cpu is exiting a low power state */
+	CPU_PM_EXIT,
+
+	/* A cpu power domain is entering a low power state */
+	CPU_CLUSTER_PM_ENTER,
+
+	/* A cpu power domain failed to enter a low power state */
+	CPU_CLUSTER_PM_ENTER_FAILED,
+
+	/* A cpu power domain is exiting a low power state */
+	CPU_CLUSTER_PM_EXIT,
+};
+
+#ifdef CONFIG_CPU_PM
+int cpu_pm_register_notifier(struct notifier_block *nb);
+int cpu_pm_unregister_notifier(struct notifier_block *nb);
+int cpu_pm_enter(void);
+int cpu_pm_exit(void);
+int cpu_cluster_pm_enter(void);
+int cpu_cluster_pm_exit(void);
+
+#else
+
+static inline int cpu_pm_register_notifier(struct notifier_block *nb)
+{
+	return 0;
+}
+
+static inline int cpu_pm_unregister_notifier(struct notifier_block *nb)
+{
+	return 0;
+}
+
+static inline int cpu_pm_enter(void)
+{
+	return 0;
+}
+
+static inline int cpu_pm_exit(void)
+{
+	return 0;
+}
+
+static inline int cpu_cluster_pm_enter(void)
+{
+	return 0;
+}
+
+static inline int cpu_cluster_pm_exit(void)
+{
+	return 0;
+}
+#endif
+#endif

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/
 

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

kernel/power/Kconfig

@@ -295,6 +295,10 @@ config PM_RUNTIME_CLK
 	def_bool y
 	depends on PM_RUNTIME && HAVE_CLK
 
+config CPU_PM
+	bool
+	depends on SUSPEND || CPU_IDLE
+
 config SUSPEND_TIME
 	bool "Log time spent in suspend"
 	---help---