diff options
Diffstat (limited to 'drivers/cpuidle')
| -rw-r--r-- | drivers/cpuidle/Makefile | 2 | ||||
| -rw-r--r-- | drivers/cpuidle/arm_big_little.c | 183 | ||||
| -rw-r--r-- | drivers/cpuidle/cpuidle-calxeda.c | 14 | ||||
| -rw-r--r-- | drivers/cpuidle/governors/menu.c | 106 |
4 files changed, 188 insertions, 117 deletions
diff --git a/drivers/cpuidle/Makefile b/drivers/cpuidle/Makefile index 0d8bd55e776..7d8256a5ea9 100644 --- a/drivers/cpuidle/Makefile +++ b/drivers/cpuidle/Makefile @@ -4,6 +4,6 @@ obj-y += cpuidle.o driver.o governor.o sysfs.o governors/ obj-$(CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED) += coupled.o - +obj-$(CONFIG_BIG_LITTLE) += arm_big_little.o obj-$(CONFIG_CPU_IDLE_CALXEDA) += cpuidle-calxeda.o obj-$(CONFIG_ARCH_KIRKWOOD) += cpuidle-kirkwood.o diff --git a/drivers/cpuidle/arm_big_little.c b/drivers/cpuidle/arm_big_little.c new file mode 100644 index 00000000000..e5378896a8c --- /dev/null +++ b/drivers/cpuidle/arm_big_little.c @@ -0,0 +1,183 @@ +/* + * big.LITTLE CPU idle driver. + * + * Copyright (C) 2012 ARM Ltd. + * Author: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com> + * + * 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. + */ + +#include <linux/arm-cci.h> +#include <linux/bitmap.h> +#include <linux/cpuidle.h> +#include <linux/cpu_pm.h> +#include <linux/clockchips.h> +#include <linux/debugfs.h> +#include <linux/hrtimer.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/tick.h> +#include <linux/vexpress.h> +#include <asm/mcpm.h> +#include <asm/cpuidle.h> +#include <asm/cputype.h> +#include <asm/idmap.h> +#include <asm/proc-fns.h> +#include <asm/suspend.h> +#include <linux/of.h> + +static int bl_cpuidle_simple_enter(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int index) +{ + ktime_t time_start, time_end; + s64 diff; + + time_start = ktime_get(); + + cpu_do_idle(); + + time_end = ktime_get(); + + local_irq_enable(); + + diff = ktime_to_us(ktime_sub(time_end, time_start)); + if (diff > INT_MAX) + diff = INT_MAX; + + dev->last_residency = (int) diff; + + return index; +} + +static int bl_enter_powerdown(struct cpuidle_device *dev, + struct cpuidle_driver *drv, int idx); + +static struct cpuidle_state bl_cpuidle_set[] __initdata = { + [0] = { + .enter = bl_cpuidle_simple_enter, + .exit_latency = 1, + .target_residency = 1, + .power_usage = UINT_MAX, + .flags = CPUIDLE_FLAG_TIME_VALID, + .name = "WFI", + .desc = "ARM WFI", + }, + [1] = { + .enter = bl_enter_powerdown, + .exit_latency = 300, + .target_residency = 1000, + .flags = CPUIDLE_FLAG_TIME_VALID, + .name = "C1", + .desc = "ARM power down", + }, +}; + +struct cpuidle_driver bl_idle_driver = { + .name = "bl_idle", + .owner = THIS_MODULE, + .safe_state_index = 0 +}; + +static DEFINE_PER_CPU(struct cpuidle_device, bl_idle_dev); + +static int notrace bl_powerdown_finisher(unsigned long arg) +{ + unsigned int mpidr = read_cpuid_mpidr(); + unsigned int cluster = (mpidr >> 8) & 0xf; + unsigned int cpu = mpidr & 0xf; + + mcpm_set_entry_vector(cpu, cluster, cpu_resume); + mcpm_cpu_suspend(0); /* 0 should be replaced with better value here */ + 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) +{ + struct timespec ts_preidle, ts_postidle, ts_idle; + int ret; + + /* Used to keep track of the total time in idle */ + getnstimeofday(&ts_preidle); + + BUG_ON(!irqs_disabled()); + + cpu_pm_enter(); + + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_ENTER, &dev->cpu); + + ret = cpu_suspend((unsigned long) dev, bl_powerdown_finisher); + if (ret) + BUG(); + + mcpm_cpu_powered_up(); + + clockevents_notify(CLOCK_EVT_NOTIFY_BROADCAST_EXIT, &dev->cpu); + + cpu_pm_exit(); + + getnstimeofday(&ts_postidle); + local_irq_enable(); + ts_idle = timespec_sub(ts_postidle, ts_preidle); + + dev->last_residency = ts_idle.tv_nsec / NSEC_PER_USEC + + ts_idle.tv_sec * USEC_PER_SEC; + return idx; +} + +/* + * bl_idle_init + * + * Registers the bl specific cpuidle driver with the cpuidle + * framework with the valid set of states. + */ +int __init bl_idle_init(void) +{ + struct cpuidle_device *dev; + int i, cpu_id; + struct cpuidle_driver *drv = &bl_idle_driver; + + if (!of_find_compatible_node(NULL, NULL, "arm,generic")) { + pr_info("%s: No compatible node found\n", __func__); + return -ENODEV; + } + + drv->state_count = (sizeof(bl_cpuidle_set) / + sizeof(struct cpuidle_state)); + + for (i = 0; i < drv->state_count; i++) { + memcpy(&drv->states[i], &bl_cpuidle_set[i], + sizeof(struct cpuidle_state)); + } + + cpuidle_register_driver(drv); + + for_each_cpu(cpu_id, cpu_online_mask) { + pr_err("CPUidle for CPU%d registered\n", cpu_id); + dev = &per_cpu(bl_idle_dev, cpu_id); + dev->cpu = cpu_id; + + dev->state_count = drv->state_count; + + if (cpuidle_register_device(dev)) { + printk(KERN_ERR "%s: Cpuidle register device failed\n", + __func__); + return -EIO; + } + } + + return 0; +} + +device_initcall(bl_idle_init); diff --git a/drivers/cpuidle/cpuidle-calxeda.c b/drivers/cpuidle/cpuidle-calxeda.c index 223379169cb..0e6e408c0a6 100644 --- a/drivers/cpuidle/cpuidle-calxeda.c +++ b/drivers/cpuidle/cpuidle-calxeda.c @@ -37,20 +37,6 @@ extern void highbank_set_cpu_jump(int cpu, void *jump_addr); extern void *scu_base_addr; -static inline unsigned int get_auxcr(void) -{ - unsigned int val; - asm("mrc p15, 0, %0, c1, c0, 1 @ get AUXCR" : "=r" (val) : : "cc"); - return val; -} - -static inline void set_auxcr(unsigned int val) -{ - asm volatile("mcr p15, 0, %0, c1, c0, 1 @ set AUXCR" - : : "r" (val) : "cc"); - isb(); -} - static noinline void calxeda_idle_restore(void) { set_cr(get_cr() | CR_C); diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c index fe343a06b7d..bc580b67a65 100644 --- a/drivers/cpuidle/governors/menu.c +++ b/drivers/cpuidle/governors/menu.c @@ -28,13 +28,6 @@ #define MAX_INTERESTING 50000 #define STDDEV_THRESH 400 -/* 60 * 60 > STDDEV_THRESH * INTERVALS = 400 * 8 */ -#define MAX_DEVIATION 60 - -static DEFINE_PER_CPU(struct hrtimer, menu_hrtimer); -static DEFINE_PER_CPU(int, hrtimer_status); -/* menu hrtimer mode */ -enum {MENU_HRTIMER_STOP, MENU_HRTIMER_REPEAT, MENU_HRTIMER_GENERAL}; /* * Concepts and ideas behind the menu governor @@ -116,13 +109,6 @@ enum {MENU_HRTIMER_STOP, MENU_HRTIMER_REPEAT, MENU_HRTIMER_GENERAL}; * */ -/* - * The C-state residency is so long that is is worthwhile to exit - * from the shallow C-state and re-enter into a deeper C-state. - */ -static unsigned int perfect_cstate_ms __read_mostly = 30; -module_param(perfect_cstate_ms, uint, 0000); - struct menu_device { int last_state_idx; int needs_update; @@ -205,52 +191,17 @@ static u64 div_round64(u64 dividend, u32 divisor) return div_u64(dividend + (divisor / 2), divisor); } -/* Cancel the hrtimer if it is not triggered yet */ -void menu_hrtimer_cancel(void) -{ - int cpu = smp_processor_id(); - struct hrtimer *hrtmr = &per_cpu(menu_hrtimer, cpu); - - /* The timer is still not time out*/ - if (per_cpu(hrtimer_status, cpu)) { - hrtimer_cancel(hrtmr); - per_cpu(hrtimer_status, cpu) = MENU_HRTIMER_STOP; - } -} -EXPORT_SYMBOL_GPL(menu_hrtimer_cancel); - -/* Call back for hrtimer is triggered */ -static enum hrtimer_restart menu_hrtimer_notify(struct hrtimer *hrtimer) -{ - int cpu = smp_processor_id(); - struct menu_device *data = &per_cpu(menu_devices, cpu); - - /* In general case, the expected residency is much larger than - * deepest C-state target residency, but prediction logic still - * predicts a small predicted residency, so the prediction - * history is totally broken if the timer is triggered. - * So reset the correction factor. - */ - if (per_cpu(hrtimer_status, cpu) == MENU_HRTIMER_GENERAL) - data->correction_factor[data->bucket] = RESOLUTION * DECAY; - - per_cpu(hrtimer_status, cpu) = MENU_HRTIMER_STOP; - - return HRTIMER_NORESTART; -} - /* * Try detecting repeating patterns by keeping track of the last 8 * intervals, and checking if the standard deviation of that set * of points is below a threshold. If it is... then use the * average of these 8 points as the estimated value. */ -static u32 get_typical_interval(struct menu_device *data) +static void get_typical_interval(struct menu_device *data) { int i = 0, divisor = 0; uint64_t max = 0, avg = 0, stddev = 0; int64_t thresh = LLONG_MAX; /* Discard outliers above this value. */ - unsigned int ret = 0; again: @@ -291,16 +242,13 @@ again: if (((avg > stddev * 6) && (divisor * 4 >= INTERVALS * 3)) || stddev <= 20) { data->predicted_us = avg; - ret = 1; - return ret; + return; } else if ((divisor * 4) > INTERVALS * 3) { /* Exclude the max interval */ thresh = max - 1; goto again; } - - return ret; } /** @@ -315,9 +263,6 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev) int i; int multiplier; struct timespec t; - int repeat = 0, low_predicted = 0; - int cpu = smp_processor_id(); - struct hrtimer *hrtmr = &per_cpu(menu_hrtimer, cpu); if (data->needs_update) { menu_update(drv, dev); @@ -352,7 +297,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev) data->predicted_us = div_round64(data->expected_us * data->correction_factor[data->bucket], RESOLUTION * DECAY); - repeat = get_typical_interval(data); + get_typical_interval(data); /* * We want to default to C1 (hlt), not to busy polling @@ -373,10 +318,8 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev) if (s->disabled || su->disable) continue; - if (s->target_residency > data->predicted_us) { - low_predicted = 1; + if (s->target_residency > data->predicted_us) continue; - } if (s->exit_latency > latency_req) continue; if (s->exit_latency * multiplier > data->predicted_us) @@ -386,44 +329,6 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev) data->exit_us = s->exit_latency; } - /* not deepest C-state chosen for low predicted residency */ - if (low_predicted) { - unsigned int timer_us = 0; - unsigned int perfect_us = 0; - - /* - * Set a timer to detect whether this sleep is much - * longer than repeat mode predicted. If the timer - * triggers, the code will evaluate whether to put - * the CPU into a deeper C-state. - * The timer is cancelled on CPU wakeup. - */ - timer_us = 2 * (data->predicted_us + MAX_DEVIATION); - - perfect_us = perfect_cstate_ms * 1000; - - if (repeat && (4 * timer_us < data->expected_us)) { - RCU_NONIDLE(hrtimer_start(hrtmr, - ns_to_ktime(1000 * timer_us), - HRTIMER_MODE_REL_PINNED)); - /* In repeat case, menu hrtimer is started */ - per_cpu(hrtimer_status, cpu) = MENU_HRTIMER_REPEAT; - } else if (perfect_us < data->expected_us) { - /* - * The next timer is long. This could be because - * we did not make a useful prediction. - * In that case, it makes sense to re-enter - * into a deeper C-state after some time. - */ - RCU_NONIDLE(hrtimer_start(hrtmr, - ns_to_ktime(1000 * timer_us), - HRTIMER_MODE_REL_PINNED)); - /* In general case, menu hrtimer is started */ - per_cpu(hrtimer_status, cpu) = MENU_HRTIMER_GENERAL; - } - - } - return data->last_state_idx; } @@ -514,9 +419,6 @@ static int menu_enable_device(struct cpuidle_driver *drv, struct cpuidle_device *dev) { struct menu_device *data = &per_cpu(menu_devices, dev->cpu); - struct hrtimer *t = &per_cpu(menu_hrtimer, dev->cpu); - hrtimer_init(t, CLOCK_MONOTONIC, HRTIMER_MODE_REL); - t->function = menu_hrtimer_notify; memset(data, 0, sizeof(struct menu_device)); |