kernel-fxtec-pro1x/include/linux/suspend.h
Zhang Rui 7e73c5ae6e PM: Introduce suspend state PM_SUSPEND_FREEZE
PM_SUSPEND_FREEZE state is a general state that
does not need any platform specific support, it equals
frozen processes + suspended devices + idle processors.

Compared with PM_SUSPEND_MEMORY,
PM_SUSPEND_FREEZE saves less power
because the system is still in a running state.
PM_SUSPEND_FREEZE has less resume latency because it does not
touch BIOS, and the processors are in idle state.

Compared with RTPM/idle,
PM_SUSPEND_FREEZE saves more power as
1. the processor has longer sleep time because processes are frozen.
   The deeper c-state the processor supports, more power saving we can get.
2. PM_SUSPEND_FREEZE uses system suspend code path, thus we can get
   more power saving from the devices that does not have good RTPM support.

This state is useful for
1) platforms that do not have STR, or have a broken STR.
2) platforms that have an extremely low power idle state,
   which can be used to replace STR.

The following describes how PM_SUSPEND_FREEZE state works.
1. echo freeze > /sys/power/state
2. the processes are frozen.
3. all the devices are suspended.
4. all the processors are blocked by a wait queue
5. all the processors idles and enters (Deep) c-state.
6. an interrupt fires.
7. a processor is woken up and handles the irq.
8. if it is a general event,
   a) the irq handler runs and quites.
   b) goto step 4.
9. if it is a real wake event, say, power button pressing, keyboard touch, mouse moving,
   a) the irq handler runs and activate the wakeup source
   b) wakeup_source_activate() notifies the wait queue.
   c) system starts resuming from PM_SUSPEND_FREEZE
10. all the devices are resumed.
11. all the processes are unfrozen.
12. system is back to working.

Known Issue:
The wakeup of this new PM_SUSPEND_FREEZE state may behave differently
from the previous suspend state.
Take ACPI platform for example, there are some GPEs that only enabled
when the system is in sleep state, to wake the system backk from S3/S4.
But we are not touching these GPEs during transition to PM_SUSPEND_FREEZE.
This means we may lose some wake event.
But on the other hand, as we do not disable all the Interrupts during
PM_SUSPEND_FREEZE, we may get some extra "wakeup" Interrupts, that are
not available for S3/S4.

The patches has been tested on an old Sony laptop, and here are the results:

Average Power:
1. RPTM/idle for half an hour:
   14.8W, 12.6W, 14.1W, 12.5W, 14.4W, 13.2W, 12.9W
2. Freeze for half an hour:
   11W, 10.4W, 9.4W, 11.3W 10.5W
3. RTPM/idle for three hours:
   11.6W
4. Freeze for three hours:
   10W
5. Suspend to Memory:
   0.5~0.9W

Average Resume Latency:
1. RTPM/idle with a black screen: (From pressing keyboard to screen back)
   Less than 0.2s
2. Freeze: (From pressing power button to screen back)
   2.50s
3. Suspend to Memory: (From pressing power button to screen back)
   4.33s

>From the results, we can see that all the platforms should benefit from
this patch, even if it does not have Low Power S0.

Signed-off-by: Zhang Rui <rui.zhang@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-02-09 22:30:44 +01:00

466 lines
16 KiB
C

#ifndef _LINUX_SUSPEND_H
#define _LINUX_SUSPEND_H
#include <linux/swap.h>
#include <linux/notifier.h>
#include <linux/init.h>
#include <linux/pm.h>
#include <linux/mm.h>
#include <linux/freezer.h>
#include <asm/errno.h>
#ifdef CONFIG_VT
extern void pm_set_vt_switch(int);
#else
static inline void pm_set_vt_switch(int do_switch)
{
}
#endif
#ifdef CONFIG_VT_CONSOLE_SLEEP
extern int pm_prepare_console(void);
extern void pm_restore_console(void);
#else
static inline int pm_prepare_console(void)
{
return 0;
}
static inline void pm_restore_console(void)
{
}
#endif
typedef int __bitwise suspend_state_t;
#define PM_SUSPEND_ON ((__force suspend_state_t) 0)
#define PM_SUSPEND_FREEZE ((__force suspend_state_t) 1)
#define PM_SUSPEND_STANDBY ((__force suspend_state_t) 2)
#define PM_SUSPEND_MEM ((__force suspend_state_t) 3)
#define PM_SUSPEND_MIN PM_SUSPEND_FREEZE
#define PM_SUSPEND_MAX ((__force suspend_state_t) 4)
enum suspend_stat_step {
SUSPEND_FREEZE = 1,
SUSPEND_PREPARE,
SUSPEND_SUSPEND,
SUSPEND_SUSPEND_LATE,
SUSPEND_SUSPEND_NOIRQ,
SUSPEND_RESUME_NOIRQ,
SUSPEND_RESUME_EARLY,
SUSPEND_RESUME
};
struct suspend_stats {
int success;
int fail;
int failed_freeze;
int failed_prepare;
int failed_suspend;
int failed_suspend_late;
int failed_suspend_noirq;
int failed_resume;
int failed_resume_early;
int failed_resume_noirq;
#define REC_FAILED_NUM 2
int last_failed_dev;
char failed_devs[REC_FAILED_NUM][40];
int last_failed_errno;
int errno[REC_FAILED_NUM];
int last_failed_step;
enum suspend_stat_step failed_steps[REC_FAILED_NUM];
};
extern struct suspend_stats suspend_stats;
static inline void dpm_save_failed_dev(const char *name)
{
strlcpy(suspend_stats.failed_devs[suspend_stats.last_failed_dev],
name,
sizeof(suspend_stats.failed_devs[0]));
suspend_stats.last_failed_dev++;
suspend_stats.last_failed_dev %= REC_FAILED_NUM;
}
static inline void dpm_save_failed_errno(int err)
{
suspend_stats.errno[suspend_stats.last_failed_errno] = err;
suspend_stats.last_failed_errno++;
suspend_stats.last_failed_errno %= REC_FAILED_NUM;
}
static inline void dpm_save_failed_step(enum suspend_stat_step step)
{
suspend_stats.failed_steps[suspend_stats.last_failed_step] = step;
suspend_stats.last_failed_step++;
suspend_stats.last_failed_step %= REC_FAILED_NUM;
}
/**
* struct platform_suspend_ops - Callbacks for managing platform dependent
* system sleep states.
*
* @valid: Callback to determine if given system sleep state is supported by
* the platform.
* Valid (ie. supported) states are advertised in /sys/power/state. Note
* that it still may be impossible to enter given system sleep state if the
* conditions aren't right.
* There is the %suspend_valid_only_mem function available that can be
* assigned to this if the platform only supports mem sleep.
*
* @begin: Initialise a transition to given system sleep state.
* @begin() is executed right prior to suspending devices. The information
* conveyed to the platform code by @begin() should be disregarded by it as
* soon as @end() is executed. If @begin() fails (ie. returns nonzero),
* @prepare(), @enter() and @finish() will not be called by the PM core.
* This callback is optional. However, if it is implemented, the argument
* passed to @enter() is redundant and should be ignored.
*
* @prepare: Prepare the platform for entering the system sleep state indicated
* by @begin().
* @prepare() is called right after devices have been suspended (ie. the
* appropriate .suspend() method has been executed for each device) and
* before device drivers' late suspend callbacks are executed. It returns
* 0 on success or a negative error code otherwise, in which case the
* system cannot enter the desired sleep state (@prepare_late(), @enter(),
* and @wake() will not be called in that case).
*
* @prepare_late: Finish preparing the platform for entering the system sleep
* state indicated by @begin().
* @prepare_late is called before disabling nonboot CPUs and after
* device drivers' late suspend callbacks have been executed. It returns
* 0 on success or a negative error code otherwise, in which case the
* system cannot enter the desired sleep state (@enter() will not be
* executed).
*
* @enter: Enter the system sleep state indicated by @begin() or represented by
* the argument if @begin() is not implemented.
* This callback is mandatory. It returns 0 on success or a negative
* error code otherwise, in which case the system cannot enter the desired
* sleep state.
*
* @wake: Called when the system has just left a sleep state, right after
* the nonboot CPUs have been enabled and before device drivers' early
* resume callbacks are executed.
* This callback is optional, but should be implemented by the platforms
* that implement @prepare_late(). If implemented, it is always called
* after @prepare_late and @enter(), even if one of them fails.
*
* @finish: Finish wake-up of the platform.
* @finish is called right prior to calling device drivers' regular suspend
* callbacks.
* This callback is optional, but should be implemented by the platforms
* that implement @prepare(). If implemented, it is always called after
* @enter() and @wake(), even if any of them fails. It is executed after
* a failing @prepare.
*
* @suspend_again: Returns whether the system should suspend again (true) or
* not (false). If the platform wants to poll sensors or execute some
* code during suspended without invoking userspace and most of devices,
* suspend_again callback is the place assuming that periodic-wakeup or
* alarm-wakeup is already setup. This allows to execute some codes while
* being kept suspended in the view of userland and devices.
*
* @end: Called by the PM core right after resuming devices, to indicate to
* the platform that the system has returned to the working state or
* the transition to the sleep state has been aborted.
* This callback is optional, but should be implemented by the platforms
* that implement @begin(). Accordingly, platforms implementing @begin()
* should also provide a @end() which cleans up transitions aborted before
* @enter().
*
* @recover: Recover the platform from a suspend failure.
* Called by the PM core if the suspending of devices fails.
* This callback is optional and should only be implemented by platforms
* which require special recovery actions in that situation.
*/
struct platform_suspend_ops {
int (*valid)(suspend_state_t state);
int (*begin)(suspend_state_t state);
int (*prepare)(void);
int (*prepare_late)(void);
int (*enter)(suspend_state_t state);
void (*wake)(void);
void (*finish)(void);
bool (*suspend_again)(void);
void (*end)(void);
void (*recover)(void);
};
#ifdef CONFIG_SUSPEND
/**
* suspend_set_ops - set platform dependent suspend operations
* @ops: The new suspend operations to set.
*/
extern void suspend_set_ops(const struct platform_suspend_ops *ops);
extern int suspend_valid_only_mem(suspend_state_t state);
extern void freeze_wake(void);
/**
* arch_suspend_disable_irqs - disable IRQs for suspend
*
* Disables IRQs (in the default case). This is a weak symbol in the common
* code and thus allows architectures to override it if more needs to be
* done. Not called for suspend to disk.
*/
extern void arch_suspend_disable_irqs(void);
/**
* arch_suspend_enable_irqs - enable IRQs after suspend
*
* Enables IRQs (in the default case). This is a weak symbol in the common
* code and thus allows architectures to override it if more needs to be
* done. Not called for suspend to disk.
*/
extern void arch_suspend_enable_irqs(void);
extern int pm_suspend(suspend_state_t state);
#else /* !CONFIG_SUSPEND */
#define suspend_valid_only_mem NULL
static inline void suspend_set_ops(const struct platform_suspend_ops *ops) {}
static inline int pm_suspend(suspend_state_t state) { return -ENOSYS; }
static inline void freeze_wake(void) {}
#endif /* !CONFIG_SUSPEND */
/* struct pbe is used for creating lists of pages that should be restored
* atomically during the resume from disk, because the page frames they have
* occupied before the suspend are in use.
*/
struct pbe {
void *address; /* address of the copy */
void *orig_address; /* original address of a page */
struct pbe *next;
};
/* mm/page_alloc.c */
extern void mark_free_pages(struct zone *zone);
/**
* struct platform_hibernation_ops - hibernation platform support
*
* The methods in this structure allow a platform to carry out special
* operations required by it during a hibernation transition.
*
* All the methods below, except for @recover(), must be implemented.
*
* @begin: Tell the platform driver that we're starting hibernation.
* Called right after shrinking memory and before freezing devices.
*
* @end: Called by the PM core right after resuming devices, to indicate to
* the platform that the system has returned to the working state.
*
* @pre_snapshot: Prepare the platform for creating the hibernation image.
* Called right after devices have been frozen and before the nonboot
* CPUs are disabled (runs with IRQs on).
*
* @finish: Restore the previous state of the platform after the hibernation
* image has been created *or* put the platform into the normal operation
* mode after the hibernation (the same method is executed in both cases).
* Called right after the nonboot CPUs have been enabled and before
* thawing devices (runs with IRQs on).
*
* @prepare: Prepare the platform for entering the low power state.
* Called right after the hibernation image has been saved and before
* devices are prepared for entering the low power state.
*
* @enter: Put the system into the low power state after the hibernation image
* has been saved to disk.
* Called after the nonboot CPUs have been disabled and all of the low
* level devices have been shut down (runs with IRQs off).
*
* @leave: Perform the first stage of the cleanup after the system sleep state
* indicated by @set_target() has been left.
* Called right after the control has been passed from the boot kernel to
* the image kernel, before the nonboot CPUs are enabled and before devices
* are resumed. Executed with interrupts disabled.
*
* @pre_restore: Prepare system for the restoration from a hibernation image.
* Called right after devices have been frozen and before the nonboot
* CPUs are disabled (runs with IRQs on).
*
* @restore_cleanup: Clean up after a failing image restoration.
* Called right after the nonboot CPUs have been enabled and before
* thawing devices (runs with IRQs on).
*
* @recover: Recover the platform from a failure to suspend devices.
* Called by the PM core if the suspending of devices during hibernation
* fails. This callback is optional and should only be implemented by
* platforms which require special recovery actions in that situation.
*/
struct platform_hibernation_ops {
int (*begin)(void);
void (*end)(void);
int (*pre_snapshot)(void);
void (*finish)(void);
int (*prepare)(void);
int (*enter)(void);
void (*leave)(void);
int (*pre_restore)(void);
void (*restore_cleanup)(void);
void (*recover)(void);
};
#ifdef CONFIG_HIBERNATION
/* kernel/power/snapshot.c */
extern void __register_nosave_region(unsigned long b, unsigned long e, int km);
static inline void __init register_nosave_region(unsigned long b, unsigned long e)
{
__register_nosave_region(b, e, 0);
}
static inline void __init register_nosave_region_late(unsigned long b, unsigned long e)
{
__register_nosave_region(b, e, 1);
}
extern int swsusp_page_is_forbidden(struct page *);
extern void swsusp_set_page_free(struct page *);
extern void swsusp_unset_page_free(struct page *);
extern unsigned long get_safe_page(gfp_t gfp_mask);
extern void hibernation_set_ops(const struct platform_hibernation_ops *ops);
extern int hibernate(void);
extern bool system_entering_hibernation(void);
#else /* CONFIG_HIBERNATION */
static inline void register_nosave_region(unsigned long b, unsigned long e) {}
static inline void register_nosave_region_late(unsigned long b, unsigned long e) {}
static inline int swsusp_page_is_forbidden(struct page *p) { return 0; }
static inline void swsusp_set_page_free(struct page *p) {}
static inline void swsusp_unset_page_free(struct page *p) {}
static inline void hibernation_set_ops(const struct platform_hibernation_ops *ops) {}
static inline int hibernate(void) { return -ENOSYS; }
static inline bool system_entering_hibernation(void) { return false; }
#endif /* CONFIG_HIBERNATION */
/* Hibernation and suspend events */
#define PM_HIBERNATION_PREPARE 0x0001 /* Going to hibernate */
#define PM_POST_HIBERNATION 0x0002 /* Hibernation finished */
#define PM_SUSPEND_PREPARE 0x0003 /* Going to suspend the system */
#define PM_POST_SUSPEND 0x0004 /* Suspend finished */
#define PM_RESTORE_PREPARE 0x0005 /* Going to restore a saved image */
#define PM_POST_RESTORE 0x0006 /* Restore failed */
extern struct mutex pm_mutex;
#ifdef CONFIG_PM_SLEEP
void save_processor_state(void);
void restore_processor_state(void);
/* kernel/power/main.c */
extern int register_pm_notifier(struct notifier_block *nb);
extern int unregister_pm_notifier(struct notifier_block *nb);
#define pm_notifier(fn, pri) { \
static struct notifier_block fn##_nb = \
{ .notifier_call = fn, .priority = pri }; \
register_pm_notifier(&fn##_nb); \
}
/* drivers/base/power/wakeup.c */
extern bool events_check_enabled;
extern bool pm_wakeup_pending(void);
extern bool pm_get_wakeup_count(unsigned int *count, bool block);
extern bool pm_save_wakeup_count(unsigned int count);
extern void pm_wakep_autosleep_enabled(bool set);
static inline void lock_system_sleep(void)
{
current->flags |= PF_FREEZER_SKIP;
mutex_lock(&pm_mutex);
}
static inline void unlock_system_sleep(void)
{
/*
* Don't use freezer_count() because we don't want the call to
* try_to_freeze() here.
*
* Reason:
* Fundamentally, we just don't need it, because freezing condition
* doesn't come into effect until we release the pm_mutex lock,
* since the freezer always works with pm_mutex held.
*
* More importantly, in the case of hibernation,
* unlock_system_sleep() gets called in snapshot_read() and
* snapshot_write() when the freezing condition is still in effect.
* Which means, if we use try_to_freeze() here, it would make them
* enter the refrigerator, thus causing hibernation to lockup.
*/
current->flags &= ~PF_FREEZER_SKIP;
mutex_unlock(&pm_mutex);
}
#else /* !CONFIG_PM_SLEEP */
static inline int register_pm_notifier(struct notifier_block *nb)
{
return 0;
}
static inline int unregister_pm_notifier(struct notifier_block *nb)
{
return 0;
}
#define pm_notifier(fn, pri) do { (void)(fn); } while (0)
static inline bool pm_wakeup_pending(void) { return false; }
static inline void lock_system_sleep(void) {}
static inline void unlock_system_sleep(void) {}
#endif /* !CONFIG_PM_SLEEP */
#ifdef CONFIG_PM_SLEEP_DEBUG
extern bool pm_print_times_enabled;
#else
#define pm_print_times_enabled (false)
#endif
#ifdef CONFIG_PM_AUTOSLEEP
/* kernel/power/autosleep.c */
void queue_up_suspend_work(void);
#else /* !CONFIG_PM_AUTOSLEEP */
static inline void queue_up_suspend_work(void) {}
#endif /* !CONFIG_PM_AUTOSLEEP */
#ifdef CONFIG_ARCH_SAVE_PAGE_KEYS
/*
* The ARCH_SAVE_PAGE_KEYS functions can be used by an architecture
* to save/restore additional information to/from the array of page
* frame numbers in the hibernation image. For s390 this is used to
* save and restore the storage key for each page that is included
* in the hibernation image.
*/
unsigned long page_key_additional_pages(unsigned long pages);
int page_key_alloc(unsigned long pages);
void page_key_free(void);
void page_key_read(unsigned long *pfn);
void page_key_memorize(unsigned long *pfn);
void page_key_write(void *address);
#else /* !CONFIG_ARCH_SAVE_PAGE_KEYS */
static inline unsigned long page_key_additional_pages(unsigned long pages)
{
return 0;
}
static inline int page_key_alloc(unsigned long pages)
{
return 0;
}
static inline void page_key_free(void) {}
static inline void page_key_read(unsigned long *pfn) {}
static inline void page_key_memorize(unsigned long *pfn) {}
static inline void page_key_write(void *address) {}
#endif /* !CONFIG_ARCH_SAVE_PAGE_KEYS */
#endif /* _LINUX_SUSPEND_H */