diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig index 663138dc7d2f..6d78f3af4ee6 100644 --- a/arch/arm/Kconfig +++ b/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 diff --git a/arch/arm/include/asm/proc-fns.h b/arch/arm/include/asm/proc-fns.h index 8ec535e11fd7..35c3fc93b88f 100644 --- a/arch/arm/include/asm/proc-fns.h +++ b/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; \ diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c index 2c277d40cee6..82347d53a877 100644 --- a/arch/arm/kernel/smp_twd.c +++ b/arch/arm/kernel/smp_twd.c @@ -10,13 +10,17 @@ */ #include #include +#include +#include #include #include +#include #include #include #include #include #include +#include #include #include @@ -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); } diff --git a/arch/arm/mm/context.c b/arch/arm/mm/context.c index b0ee9ba3cfab..131f381712c9 100644 --- a/arch/arm/mm/context.c +++ b/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 diff --git a/arch/arm/vfp/vfpmodule.c b/arch/arm/vfp/vfpmodule.c index 53cb06fc3165..bfd1e2f40de4 100644 --- a/arch/arm/vfp/vfpmodule.c +++ b/arch/arm/vfp/vfpmodule.c @@ -11,6 +11,7 @@ #include #include #include +#include #include #include #include @@ -403,9 +404,7 @@ static void vfp_enable(void *unused) set_copro_access(access | CPACC_FULL(10) | CPACC_FULL(11)); } -#ifdef CONFIG_PM -#include - +#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) { diff --git a/include/linux/cpu_pm.h b/include/linux/cpu_pm.h new file mode 100644 index 000000000000..455b233dd3b1 --- /dev/null +++ b/include/linux/cpu_pm.h @@ -0,0 +1,109 @@ +/* + * Copyright (C) 2011 Google, Inc. + * + * Author: + * Colin Cross + * + * 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 +#include + +/* + * 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 diff --git a/kernel/Makefile b/kernel/Makefile index 2d64cfcc8b42..e4fd98bb7459 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 + * + * 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 +#include +#include +#include +#include +#include + +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/power/Kconfig b/kernel/power/Kconfig index d50bb90e1c1f..f16f2ff20881 100644 --- a/kernel/power/Kconfig +++ b/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---