diff options
Diffstat (limited to 'drivers/cpuidle')
| -rw-r--r-- | drivers/cpuidle/Kconfig.arm | 19 | ||||
| -rw-r--r-- | drivers/cpuidle/Makefile | 2 | ||||
| -rw-r--r-- | drivers/cpuidle/coupled.c | 2 | ||||
| -rw-r--r-- | drivers/cpuidle/cpuidle-at91.c | 69 | ||||
| -rw-r--r-- | drivers/cpuidle/cpuidle-big_little.c | 209 | ||||
| -rw-r--r-- | drivers/cpuidle/cpuidle-calxeda.c | 61 | ||||
| -rw-r--r-- | drivers/cpuidle/cpuidle-ux500.c | 2 | ||||
| -rw-r--r-- | drivers/cpuidle/cpuidle-zynq.c | 17 | ||||
| -rw-r--r-- | drivers/cpuidle/cpuidle.c | 80 | ||||
| -rw-r--r-- | drivers/cpuidle/driver.c | 70 | ||||
| -rw-r--r-- | drivers/cpuidle/governor.c | 43 | ||||
| -rw-r--r-- | drivers/cpuidle/sysfs.c | 7 |
12 files changed, 406 insertions, 175 deletions
diff --git a/drivers/cpuidle/Kconfig.arm b/drivers/cpuidle/Kconfig.arm index b3302193c15a..d988948a89a0 100644 --- a/drivers/cpuidle/Kconfig.arm +++ b/drivers/cpuidle/Kconfig.arm @@ -2,9 +2,20 @@ # ARM CPU Idle drivers # +config ARM_BIG_LITTLE_CPUIDLE + bool "Support for ARM big.LITTLE processors" + depends on ARCH_VEXPRESS_TC2_PM + select ARM_CPU_SUSPEND + select CPU_IDLE_MULTIPLE_DRIVERS + help + Select this option to enable CPU idle driver for big.LITTLE based + ARM systems. Driver manages CPUs coordination through MCPM and + define different C-states for little and big cores through the + multiple CPU idle drivers infrastructure. + config ARM_HIGHBANK_CPUIDLE bool "CPU Idle Driver for Calxeda processors" - depends on ARCH_HIGHBANK + depends on ARM_PSCI select ARM_CPU_SUSPEND help Select this to enable cpuidle on Calxeda processors. @@ -27,3 +38,9 @@ config ARM_U8500_CPUIDLE help Select this to enable cpuidle for ST-E u8500 processors +config ARM_AT91_CPUIDLE + bool "Cpu Idle Driver for the AT91 processors" + default y + depends on ARCH_AT91 + help + Select this to enable cpuidle for AT91 processors diff --git a/drivers/cpuidle/Makefile b/drivers/cpuidle/Makefile index 0b9d200c7e45..527be28e5c1e 100644 --- a/drivers/cpuidle/Makefile +++ b/drivers/cpuidle/Makefile @@ -7,7 +7,9 @@ obj-$(CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED) += coupled.o ################################################################################## # ARM SoC drivers +obj-$(CONFIG_ARM_BIG_LITTLE_CPUIDLE) += cpuidle-big_little.o obj-$(CONFIG_ARM_HIGHBANK_CPUIDLE) += cpuidle-calxeda.o obj-$(CONFIG_ARM_KIRKWOOD_CPUIDLE) += cpuidle-kirkwood.o obj-$(CONFIG_ARM_ZYNQ_CPUIDLE) += cpuidle-zynq.o obj-$(CONFIG_ARM_U8500_CPUIDLE) += cpuidle-ux500.o +obj-$(CONFIG_ARM_AT91_CPUIDLE) += cpuidle-at91.o diff --git a/drivers/cpuidle/coupled.c b/drivers/cpuidle/coupled.c index f8a86364c6b6..e952936418d0 100644 --- a/drivers/cpuidle/coupled.c +++ b/drivers/cpuidle/coupled.c @@ -147,7 +147,7 @@ static cpumask_t cpuidle_coupled_poked; * has returned from this function, the barrier is immediately available for * reuse. * - * The atomic variable a must be initialized to 0 before any cpu calls + * The atomic variable must be initialized to 0 before any cpu calls * this function, will be reset to 0 before any cpu returns from this function. * * Must only be called from within a coupled idle state handler diff --git a/drivers/cpuidle/cpuidle-at91.c b/drivers/cpuidle/cpuidle-at91.c new file mode 100644 index 000000000000..a0774370c6bc --- /dev/null +++ b/drivers/cpuidle/cpuidle-at91.c @@ -0,0 +1,69 @@ +/* + * based on arch/arm/mach-kirkwood/cpuidle.c + * + * CPU idle support for AT91 SoC + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + * + * The cpu idle uses wait-for-interrupt and RAM self refresh in order + * to implement two idle states - + * #1 wait-for-interrupt + * #2 wait-for-interrupt and RAM self refresh + */ + +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/platform_device.h> +#include <linux/cpuidle.h> +#include <linux/io.h> +#include <linux/export.h> +#include <asm/proc-fns.h> +#include <asm/cpuidle.h> + +#define AT91_MAX_STATES 2 + +static void (*at91_standby)(void); + +/* Actual code that puts the SoC in different idle states */ +static int at91_enter_idle(struct cpuidle_device *dev, + struct cpuidle_driver *drv, + int index) +{ + at91_standby(); + return index; +} + +static struct cpuidle_driver at91_idle_driver = { + .name = "at91_idle", + .owner = THIS_MODULE, + .states[0] = ARM_CPUIDLE_WFI_STATE, + .states[1] = { + .enter = at91_enter_idle, + .exit_latency = 10, + .target_residency = 10000, + .flags = CPUIDLE_FLAG_TIME_VALID, + .name = "RAM_SR", + .desc = "WFI and DDR Self Refresh", + }, + .state_count = AT91_MAX_STATES, +}; + +/* Initialize CPU idle by registering the idle states */ +static int at91_cpuidle_probe(struct platform_device *dev) +{ + at91_standby = (void *)(dev->dev.platform_data); + + return cpuidle_register(&at91_idle_driver, NULL); +} + +static struct platform_driver at91_cpuidle_driver = { + .driver = { + .name = "cpuidle-at91", + .owner = THIS_MODULE, + }, + .probe = at91_cpuidle_probe, +}; + +module_platform_driver(at91_cpuidle_driver); diff --git a/drivers/cpuidle/cpuidle-big_little.c b/drivers/cpuidle/cpuidle-big_little.c new file mode 100644 index 000000000000..b45fc6249041 --- /dev/null +++ b/drivers/cpuidle/cpuidle-big_little.c @@ -0,0 +1,209 @@ +/* + * Copyright (c) 2013 ARM/Linaro + * + * Authors: Daniel Lezcano <daniel.lezcano@linaro.org> + * Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> + * Nicolas Pitre <nicolas.pitre@linaro.org> + * + * 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. + * + * Maintainer: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> + * Maintainer: Daniel Lezcano <daniel.lezcano@linaro.org> + */ +#include <linux/cpuidle.h> +#include <linux/cpu_pm.h> +#include <linux/slab.h> +#include <linux/of.h> + +#include <asm/cpu.h> +#include <asm/cputype.h> +#include <asm/cpuidle.h> +#include <asm/mcpm.h> +#include <asm/smp_plat.h> +#include <asm/suspend.h> + +static int bl_enter_powerdown(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int idx); + +/* + * NB: Owing to current menu governor behaviour big and LITTLE + * index 1 states have to define exit_latency and target_residency for + * cluster state since, when all CPUs in a cluster hit it, the cluster + * can be shutdown. This means that when a single CPU enters this state + * the exit_latency and target_residency values are somewhat overkill. + * There is no notion of cluster states in the menu governor, so CPUs + * have to define CPU states where possibly the cluster will be shutdown + * depending on the state of other CPUs. idle states entry and exit happen + * at random times; however the cluster state provides target_residency + * values as if all CPUs in a cluster enter the state at once; this is + * somewhat optimistic and behaviour should be fixed either in the governor + * or in the MCPM back-ends. + * To make this driver 100% generic the number of states and the exit_latency + * target_residency values must be obtained from device tree bindings. + * + * exit_latency: refers to the TC2 vexpress test chip and depends on the + * current cluster operating point. It is the time it takes to get the CPU + * up and running when the CPU is powered up on cluster wake-up from shutdown. + * Current values for big and LITTLE clusters are provided for clusters + * running at default operating points. + * + * target_residency: it is the minimum amount of time the cluster has + * to be down to break even in terms of power consumption. cluster + * shutdown has inherent dynamic power costs (L2 writebacks to DRAM + * being the main factor) that depend on the current operating points. + * The current values for both clusters are provided for a CPU whose half + * of L2 lines are dirty and require cleaning to DRAM, and takes into + * account leakage static power values related to the vexpress TC2 testchip. + */ +static struct cpuidle_driver bl_idle_little_driver = { + .name = "little_idle", + .owner = THIS_MODULE, + .states[0] = ARM_CPUIDLE_WFI_STATE, + .states[1] = { + .enter = bl_enter_powerdown, + .exit_latency = 700, + .target_residency = 2500, + .flags = CPUIDLE_FLAG_TIME_VALID | + CPUIDLE_FLAG_TIMER_STOP, + .name = "C1", + .desc = "ARM little-cluster power down", + }, + .state_count = 2, +}; + +static struct cpuidle_driver bl_idle_big_driver = { + .name = "big_idle", + .owner = THIS_MODULE, + .states[0] = ARM_CPUIDLE_WFI_STATE, + .states[1] = { + .enter = bl_enter_powerdown, + .exit_latency = 500, + .target_residency = 2000, + .flags = CPUIDLE_FLAG_TIME_VALID | + CPUIDLE_FLAG_TIMER_STOP, + .name = "C1", + .desc = "ARM big-cluster power down", + }, + .state_count = 2, +}; + +/* + * notrace prevents trace shims from getting inserted where they + * should not. Global jumps and ldrex/strex must not be inserted + * in power down sequences where caches and MMU may be turned off. + */ +static int notrace bl_powerdown_finisher(unsigned long arg) +{ + /* MCPM works with HW CPU identifiers */ + unsigned int mpidr = read_cpuid_mpidr(); + unsigned int cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1); + unsigned int cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0); + + mcpm_set_entry_vector(cpu, cluster, cpu_resume); + + /* + * Residency value passed to mcpm_cpu_suspend back-end + * has to be given clear semantics. Set to 0 as a + * temporary value. + */ + mcpm_cpu_suspend(0); + + /* return value != 0 means failure */ + return 1; +} + +/** + * bl_enter_powerdown - Programs CPU to enter the specified state + * @dev: cpuidle device + * @drv: The target state to be programmed + * @idx: state index + * + * Called from the CPUidle framework to program the device to the + * specified target state selected by the governor. + */ +static int bl_enter_powerdown(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int idx) +{ + cpu_pm_enter(); + + cpu_suspend(0, bl_powerdown_finisher); + + /* signals the MCPM core that CPU is out of low power state */ + mcpm_cpu_powered_up(); + + cpu_pm_exit(); + + return idx; +} + +static int __init bl_idle_driver_init(struct cpuidle_driver *drv, int cpu_id) +{ + struct cpuinfo_arm *cpu_info; + struct cpumask *cpumask; + unsigned long cpuid; + int cpu; + + cpumask = kzalloc(cpumask_size(), GFP_KERNEL); + if (!cpumask) + return -ENOMEM; + + for_each_possible_cpu(cpu) { + cpu_info = &per_cpu(cpu_data, cpu); + cpuid = is_smp() ? cpu_info->cpuid : read_cpuid_id(); + + /* read cpu id part number */ + if ((cpuid & 0xFFF0) == cpu_id) + cpumask_set_cpu(cpu, cpumask); + } + + drv->cpumask = cpumask; + + return 0; +} + +static int __init bl_idle_init(void) +{ + int ret; + + /* + * Initialize the driver just for a compliant set of machines + */ + if (!of_machine_is_compatible("arm,vexpress,v2p-ca15_a7")) + return -ENODEV; + /* + * For now the differentiation between little and big cores + * is based on the part number. A7 cores are considered little + * cores, A15 are considered big cores. This distinction may + * evolve in the future with a more generic matching approach. + */ + ret = bl_idle_driver_init(&bl_idle_little_driver, + ARM_CPU_PART_CORTEX_A7); + if (ret) + return ret; + + ret = bl_idle_driver_init(&bl_idle_big_driver, ARM_CPU_PART_CORTEX_A15); + if (ret) + goto out_uninit_little; + + ret = cpuidle_register(&bl_idle_little_driver, NULL); + if (ret) + goto out_uninit_big; + + ret = cpuidle_register(&bl_idle_big_driver, NULL); + if (ret) + goto out_unregister_little; + + return 0; + +out_unregister_little: + cpuidle_unregister(&bl_idle_little_driver); +out_uninit_big: + kfree(bl_idle_big_driver.cpumask); +out_uninit_little: + kfree(bl_idle_little_driver.cpumask); + + return ret; +} +device_initcall(bl_idle_init); diff --git a/drivers/cpuidle/cpuidle-calxeda.c b/drivers/cpuidle/cpuidle-calxeda.c index 346058479572..36795639df0d 100644 --- a/drivers/cpuidle/cpuidle-calxeda.c +++ b/drivers/cpuidle/cpuidle-calxeda.c @@ -21,53 +21,30 @@ */ #include <linux/cpuidle.h> +#include <linux/cpu_pm.h> #include <linux/init.h> -#include <linux/io.h> -#include <linux/of.h> -#include <linux/time.h> -#include <linux/delay.h> -#include <linux/suspend.h> +#include <linux/mm.h> +#include <linux/platform_device.h> #include <asm/cpuidle.h> -#include <asm/proc-fns.h> -#include <asm/smp_scu.h> #include <asm/suspend.h> -#include <asm/cacheflush.h> -#include <asm/cp15.h> - -extern void highbank_set_cpu_jump(int cpu, void *jump_addr); -extern void __iomem *scu_base_addr; - -static noinline void calxeda_idle_restore(void) -{ - set_cr(get_cr() | CR_C); - set_auxcr(get_auxcr() | 0x40); - scu_power_mode(scu_base_addr, SCU_PM_NORMAL); -} +#include <asm/psci.h> static int calxeda_idle_finish(unsigned long val) { - /* Already flushed cache, but do it again as the outer cache functions - * dirty the cache with spinlocks */ - flush_cache_all(); - - set_auxcr(get_auxcr() & ~0x40); - set_cr(get_cr() & ~CR_C); - - scu_power_mode(scu_base_addr, SCU_PM_DORMANT); - - cpu_do_idle(); - - /* Restore things if we didn't enter power-gating */ - calxeda_idle_restore(); - return 1; + const struct psci_power_state ps = { + .type = PSCI_POWER_STATE_TYPE_POWER_DOWN, + }; + return psci_ops.cpu_suspend(ps, __pa(cpu_resume)); } static int calxeda_pwrdown_idle(struct cpuidle_device *dev, struct cpuidle_driver *drv, int index) { - highbank_set_cpu_jump(smp_processor_id(), cpu_resume); + cpu_pm_enter(); cpu_suspend(0, calxeda_idle_finish); + cpu_pm_exit(); + return index; } @@ -88,11 +65,17 @@ static struct cpuidle_driver calxeda_idle_driver = { .state_count = 2, }; -static int __init calxeda_cpuidle_init(void) +static int __init calxeda_cpuidle_probe(struct platform_device *pdev) { - if (!of_machine_is_compatible("calxeda,highbank")) - return -ENODEV; - return cpuidle_register(&calxeda_idle_driver, NULL); } -module_init(calxeda_cpuidle_init); + +static struct platform_driver calxeda_cpuidle_plat_driver = { + .driver = { + .name = "cpuidle-calxeda", + .owner = THIS_MODULE, + }, + .probe = calxeda_cpuidle_probe, +}; + +module_platform_driver(calxeda_cpuidle_plat_driver); diff --git a/drivers/cpuidle/cpuidle-ux500.c b/drivers/cpuidle/cpuidle-ux500.c index e0564652af35..5e35804b1a95 100644 --- a/drivers/cpuidle/cpuidle-ux500.c +++ b/drivers/cpuidle/cpuidle-ux500.c @@ -111,7 +111,7 @@ static struct cpuidle_driver ux500_idle_driver = { .state_count = 2, }; -static int __init dbx500_cpuidle_probe(struct platform_device *pdev) +static int dbx500_cpuidle_probe(struct platform_device *pdev) { /* Configure wake up reasons */ prcmu_enable_wakeups(PRCMU_WAKEUP(ARM) | PRCMU_WAKEUP(RTC) | diff --git a/drivers/cpuidle/cpuidle-zynq.c b/drivers/cpuidle/cpuidle-zynq.c index 38e03a183591..aded75928028 100644 --- a/drivers/cpuidle/cpuidle-zynq.c +++ b/drivers/cpuidle/cpuidle-zynq.c @@ -28,7 +28,7 @@ #include <linux/init.h> #include <linux/cpu_pm.h> #include <linux/cpuidle.h> -#include <linux/of.h> +#include <linux/platform_device.h> #include <asm/proc-fns.h> #include <asm/cpuidle.h> @@ -70,14 +70,19 @@ static struct cpuidle_driver zynq_idle_driver = { }; /* Initialize CPU idle by registering the idle states */ -static int __init zynq_cpuidle_init(void) +static int zynq_cpuidle_probe(struct platform_device *pdev) { - if (!of_machine_is_compatible("xlnx,zynq-7000")) - return -ENODEV; - pr_info("Xilinx Zynq CpuIdle Driver started\n"); return cpuidle_register(&zynq_idle_driver, NULL); } -device_initcall(zynq_cpuidle_init); +static struct platform_driver zynq_cpuidle_driver = { + .driver = { + .name = "cpuidle-zynq", + .owner = THIS_MODULE, + }, + .probe = zynq_cpuidle_probe, +}; + +module_platform_driver(zynq_cpuidle_driver); diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c index d75040ddd2b3..a55e68f2cfc8 100644 --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -118,11 +118,9 @@ int cpuidle_idle_call(void) struct cpuidle_device *dev = __this_cpu_read(cpuidle_devices); struct cpuidle_driver *drv; int next_state, entered_state; + bool broadcast; - if (off) - return -ENODEV; - - if (!initialized) + if (off || !initialized) return -ENODEV; /* check if the device is ready */ @@ -144,9 +142,10 @@ int cpuidle_idle_call(void) trace_cpu_idle_rcuidle(next_state, dev->cpu); - if (drv->states[next_state].flags & CPUIDLE_FLAG_TIMER_STOP) - clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, - &dev->cpu); + broadcast = !!(drv->states[next_state].flags & CPUIDLE_FLAG_TIMER_STOP); + + if (broadcast) + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &dev->cpu); if (cpuidle_state_is_coupled(dev, drv, next_state)) entered_state = cpuidle_enter_state_coupled(dev, drv, @@ -154,9 +153,8 @@ int cpuidle_idle_call(void) else entered_state = cpuidle_enter_state(dev, drv, next_state); - if (drv->states[next_state].flags & CPUIDLE_FLAG_TIMER_STOP) - clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, - &dev->cpu); + if (broadcast) + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &dev->cpu); trace_cpu_idle_rcuidle(PWR_EVENT_EXIT, dev->cpu); @@ -228,45 +226,6 @@ void cpuidle_resume(void) mutex_unlock(&cpuidle_lock); } -#ifdef CONFIG_ARCH_HAS_CPU_RELAX -static int poll_idle(struct cpuidle_device *dev, - struct cpuidle_driver *drv, int index) -{ - ktime_t t1, t2; - s64 diff; - - t1 = ktime_get(); - local_irq_enable(); - while (!need_resched()) - cpu_relax(); - - t2 = ktime_get(); - diff = ktime_to_us(ktime_sub(t2, t1)); - if (diff > INT_MAX) - diff = INT_MAX; - - dev->last_residency = (int) diff; - - return index; -} - -static void poll_idle_init(struct cpuidle_driver *drv) -{ - struct cpuidle_state *state = &drv->states[0]; - - snprintf(state->name, CPUIDLE_NAME_LEN, "POLL"); - snprintf(state->desc, CPUIDLE_DESC_LEN, "CPUIDLE CORE POLL IDLE"); - state->exit_latency = 0; - state->target_residency = 0; - state->power_usage = -1; - state->flags = 0; - state->enter = poll_idle; - state->disabled = false; -} -#else -static void poll_idle_init(struct cpuidle_driver *drv) {} -#endif /* CONFIG_ARCH_HAS_CPU_RELAX */ - /** * cpuidle_enable_device - enables idle PM for a CPU * @dev: the CPU @@ -296,8 +255,6 @@ int cpuidle_enable_device(struct cpuidle_device *dev) if (!dev->state_count) dev->state_count = drv->state_count; - poll_idle_init(drv); - ret = cpuidle_add_device_sysfs(dev); if (ret) return ret; @@ -358,12 +315,10 @@ static void __cpuidle_unregister_device(struct cpuidle_device *dev) module_put(drv->owner); } -static int __cpuidle_device_init(struct cpuidle_device *dev) +static void __cpuidle_device_init(struct cpuidle_device *dev) { memset(dev->states_usage, 0, sizeof(dev->states_usage)); dev->last_residency = 0; - - return 0; } /** @@ -385,13 +340,12 @@ static int __cpuidle_register_device(struct cpuidle_device *dev) list_add(&dev->device_list, &cpuidle_detected_devices); ret = cpuidle_coupled_register_device(dev); - if (ret) { + if (ret) __cpuidle_unregister_device(dev); - return ret; - } + else + dev->registered = 1; - dev->registered = 1; - return 0; + return ret; } /** @@ -410,9 +364,7 @@ int cpuidle_register_device(struct cpuidle_device *dev) if (dev->registered) goto out_unlock; - ret = __cpuidle_device_init(dev); - if (ret) - goto out_unlock; + __cpuidle_device_init(dev); ret = __cpuidle_register_device(dev); if (ret) @@ -448,7 +400,7 @@ EXPORT_SYMBOL_GPL(cpuidle_register_device); */ void cpuidle_unregister_device(struct cpuidle_device *dev) { - if (dev->registered == 0) + if (!dev || dev->registered == 0) return; cpuidle_pause_and_lock(); @@ -516,7 +468,7 @@ int cpuidle_register(struct cpuidle_driver *drv, #ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED /* - * On multiplatform for ARM, the coupled idle states could + * On multiplatform for ARM, the coupled idle states could be * enabled in the kernel even if the cpuidle driver does not * use it. Note, coupled_cpus is a struct copy. */ diff --git a/drivers/cpuidle/driver.c b/drivers/cpuidle/driver.c index 3ac499d5a207..06dbe7c86199 100644 --- a/drivers/cpuidle/driver.c +++ b/drivers/cpuidle/driver.c @@ -10,6 +10,7 @@ #include <linux/mutex.h> #include <linux/module.h> +#include <linux/sched.h> #include <linux/cpuidle.h> #include <linux/cpumask.h> #include <linux/clockchips.h> @@ -56,7 +57,7 @@ static inline void __cpuidle_unset_driver(struct cpuidle_driver *drv) } /** - * __cpuidle_set_driver - set per CPU driver variables the the given driver. + * __cpuidle_set_driver - set per CPU driver variables for the given driver. * @drv: a valid pointer to a struct cpuidle_driver * * For each CPU in the driver's cpumask, unset the registered driver per CPU @@ -132,7 +133,7 @@ static inline void __cpuidle_unset_driver(struct cpuidle_driver *drv) * cpuidle_setup_broadcast_timer - enable/disable the broadcast timer * @arg: a void pointer used to match the SMP cross call API * - * @arg is used as a value of type 'long' with on of the two values: + * @arg is used as a value of type 'long' with one of the two values: * - CLOCK_EVT_NOTIFY_BROADCAST_ON * - CLOCK_EVT_NOTIFY_BROADCAST_OFF * @@ -149,10 +150,8 @@ static void cpuidle_setup_broadcast_timer(void *arg) /** * __cpuidle_driver_init - initialize the driver's internal data * @drv: a valid pointer to a struct cpuidle_driver - * - * Returns 0 on success, a negative error code otherwise. */ -static int __cpuidle_driver_init(struct cpuidle_driver *drv) +static void __cpuidle_driver_init(struct cpuidle_driver *drv) { int i; @@ -169,20 +168,55 @@ static int __cpuidle_driver_init(struct cpuidle_driver *drv) /* * Look for the timer stop flag in the different states, so that we know * if the broadcast timer has to be set up. The loop is in the reverse - * order, because usually on of the the deeper states has this flag set. + * order, because usually one of the deeper states have this flag set. */ for (i = drv->state_count - 1; i >= 0 ; i--) { + if (drv->states[i].flags & CPUIDLE_FLAG_TIMER_STOP) { + drv->bctimer = 1; + break; + } + } +} - if (!(drv->states[i].flags & CPUIDLE_FLAG_TIMER_STOP)) - continue; +#ifdef CONFIG_ARCH_HAS_CPU_RELAX +static int poll_idle(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index) +{ + ktime_t t1, t2; + s64 diff; - drv->bctimer = 1; - break; - } + t1 = ktime_get(); + local_irq_enable(); + while (!need_resched()) + cpu_relax(); - return 0; + t2 = ktime_get(); + diff = ktime_to_us(ktime_sub(t2, t1)); + if (diff > INT_MAX) + diff = INT_MAX; + + dev->last_residency = (int) diff; + + return index; } +static void poll_idle_init(struct cpuidle_driver *drv) +{ + struct cpuidle_state *state = &drv->states[0]; + + snprintf(state->name, CPUIDLE_NAME_LEN, "POLL"); + snprintf(state->desc, CPUIDLE_DESC_LEN, "CPUIDLE CORE POLL IDLE"); + state->exit_latency = 0; + state->target_residency = 0; + state->power_usage = -1; + state->flags = 0; + state->enter = poll_idle; + state->disabled = false; +} +#else +static void poll_idle_init(struct cpuidle_driver *drv) {} +#endif /* !CONFIG_ARCH_HAS_CPU_RELAX */ + /** * __cpuidle_register_driver: register the driver * @drv: a valid pointer to a struct cpuidle_driver @@ -206,9 +240,7 @@ static int __cpuidle_register_driver(struct cpuidle_driver *drv) if (cpuidle_disabled()) return -ENODEV; - ret = __cpuidle_driver_init(drv); - if (ret) - return ret; + __cpuidle_driver_init(drv); ret = __cpuidle_set_driver(drv); if (ret) @@ -218,6 +250,8 @@ static int __cpuidle_register_driver(struct cpuidle_driver *drv) on_each_cpu_mask(drv->cpumask, cpuidle_setup_broadcast_timer, (void *)CLOCK_EVT_NOTIFY_BROADCAST_ON, 1); + poll_idle_init(drv); + return 0; } @@ -331,7 +365,8 @@ struct cpuidle_driver *cpuidle_driver_ref(void) spin_lock(&cpuidle_driver_lock); drv = cpuidle_get_driver(); - drv->refcnt++; + if (drv) + drv->refcnt++; spin_unlock(&cpuidle_driver_lock); return drv; @@ -345,10 +380,11 @@ struct cpuidle_driver *cpuidle_driver_ref(void) */ void cpuidle_driver_unref(void) { - struct cpuidle_driver *drv = cpuidle_get_driver(); + struct cpuidle_driver *drv; spin_lock(&cpuidle_driver_lock); + drv = cpuidle_get_driver(); if (drv && !WARN_ON(drv->refcnt <= 0)) drv->refcnt--; diff --git a/drivers/cpuidle/governor.c b/drivers/cpuidle/governor.c index ea2f8e7aa24a..ca89412f5122 100644 --- a/drivers/cpuidle/governor.c +++ b/drivers/cpuidle/governor.c @@ -96,46 +96,3 @@ int cpuidle_register_governor(struct cpuidle_governor *gov) return ret; } - -/** - * cpuidle_replace_governor - find a replacement governor - * @exclude_rating: the rating that will be skipped while looking for - * new governor. - */ -static struct cpuidle_governor *cpuidle_replace_governor(int exclude_rating) -{ - struct cpuidle_governor *gov; - struct cpuidle_governor *ret_gov = NULL; - unsigned int max_rating = 0; - - list_for_each_entry(gov, &cpuidle_governors, governor_list) { - if (gov->rating == exclude_rating) - continue; - if (gov->rating > max_rating) { - max_rating = gov->rating; - ret_gov = gov; - } - } - - return ret_gov; -} - -/** - * cpuidle_unregister_governor - unregisters a governor - * @gov: the governor - */ -void cpuidle_unregister_governor(struct cpuidle_governor *gov) -{ - if (!gov) - return; - - mutex_lock(&cpuidle_lock); - if (gov == cpuidle_curr_governor) { - struct cpuidle_governor *new_gov; - new_gov = cpuidle_replace_governor(gov->rating); - cpuidle_switch_governor(new_gov); - } - list_del(&gov->governor_list); - mutex_unlock(&cpuidle_lock); -} - diff --git a/drivers/cpuidle/sysfs.c b/drivers/cpuidle/sysfs.c index 8739cc05228c..e918b6d0caf7 100644 --- a/drivers/cpuidle/sysfs.c +++ b/drivers/cpuidle/sysfs.c @@ -52,11 +52,12 @@ static ssize_t show_current_driver(struct device *dev, char *buf) { ssize_t ret; - struct cpuidle_driver *cpuidle_driver = cpuidle_get_driver(); + struct cpuidle_driver *drv; spin_lock(&cpuidle_driver_lock); - if (cpuidle_driver) - ret = sprintf(buf, "%s\n", cpuidle_driver->name); + drv = cpuidle_get_driver(); + if (drv) + ret = sprintf(buf, "%s\n", drv->name); else ret = sprintf(buf, "none\n"); spin_unlock(&cpuidle_driver_lock); |