kernel-fxtec-pro1x/include/linux/clockchips.h

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/* linux/include/linux/clockchips.h
*
* This file contains the structure definitions for clockchips.
*
* If you are not a clockchip, or the time of day code, you should
* not be including this file!
*/
#ifndef _LINUX_CLOCKCHIPS_H
#define _LINUX_CLOCKCHIPS_H
#ifdef CONFIG_GENERIC_CLOCKEVENTS_BUILD
#include <linux/clocksource.h>
#include <linux/cpumask.h>
#include <linux/ktime.h>
#include <linux/notifier.h>
struct clock_event_device;
/* Clock event mode commands */
enum clock_event_mode {
CLOCK_EVT_MODE_UNUSED = 0,
CLOCK_EVT_MODE_SHUTDOWN,
CLOCK_EVT_MODE_PERIODIC,
CLOCK_EVT_MODE_ONESHOT,
CLOCK_EVT_MODE_RESUME,
};
/* Clock event notification values */
enum clock_event_nofitiers {
CLOCK_EVT_NOTIFY_ADD,
CLOCK_EVT_NOTIFY_BROADCAST_ON,
CLOCK_EVT_NOTIFY_BROADCAST_OFF,
CLOCK_EVT_NOTIFY_BROADCAST_FORCE,
CLOCK_EVT_NOTIFY_BROADCAST_ENTER,
CLOCK_EVT_NOTIFY_BROADCAST_EXIT,
CLOCK_EVT_NOTIFY_SUSPEND,
CLOCK_EVT_NOTIFY_RESUME,
CLOCK_EVT_NOTIFY_CPU_DYING,
CLOCK_EVT_NOTIFY_CPU_DEAD,
};
/*
* Clock event features
*/
#define CLOCK_EVT_FEAT_PERIODIC 0x000001
#define CLOCK_EVT_FEAT_ONESHOT 0x000002
#define CLOCK_EVT_FEAT_KTIME 0x000004
/*
* x86(64) specific misfeatures:
*
* - Clockevent source stops in C3 State and needs broadcast support.
* - Local APIC timer is used as a dummy device.
*/
#define CLOCK_EVT_FEAT_C3STOP 0x000008
#define CLOCK_EVT_FEAT_DUMMY 0x000010
/**
* struct clock_event_device - clock event device descriptor
* @event_handler: Assigned by the framework to be called by the low
* level handler of the event source
* @set_next_event: set next event function using a clocksource delta
* @set_next_ktime: set next event function using a direct ktime value
* @next_event: local storage for the next event in oneshot mode
* @max_delta_ns: maximum delta value in ns
* @min_delta_ns: minimum delta value in ns
* @mult: nanosecond to cycles multiplier
* @shift: nanoseconds to cycles divisor (power of two)
* @mode: operating mode assigned by the management code
* @features: features
* @retries: number of forced programming retries
* @set_mode: set mode function
* @broadcast: function to broadcast events
* @min_delta_ticks: minimum delta value in ticks stored for reconfiguration
* @max_delta_ticks: maximum delta value in ticks stored for reconfiguration
* @name: ptr to clock event name
* @rating: variable to rate clock event devices
* @irq: IRQ number (only for non CPU local devices)
* @cpumask: cpumask to indicate for which CPUs this device works
* @list: list head for the management code
*/
struct clock_event_device {
void (*event_handler)(struct clock_event_device *);
int (*set_next_event)(unsigned long evt,
struct clock_event_device *);
int (*set_next_ktime)(ktime_t expires,
struct clock_event_device *);
ktime_t next_event;
nohz: Allow 32-bit machines to sleep for more than 2.15 seconds In the dynamic tick code, "max_delta_ns" (member of the "clock_event_device" structure) represents the maximum sleep time that can occur between timer events in nanoseconds. The variable, "max_delta_ns", is defined as an unsigned long which is a 32-bit integer for 32-bit machines and a 64-bit integer for 64-bit machines (if -m64 option is used for gcc). The value of max_delta_ns is set by calling the function "clockevent_delta2ns()" which returns a maximum value of LONG_MAX. For a 32-bit machine LONG_MAX is equal to 0x7fffffff and in nanoseconds this equates to ~2.15 seconds. Hence, the maximum sleep time for a 32-bit machine is ~2.15 seconds, where as for a 64-bit machine it will be many years. This patch changes the type of max_delta_ns to be "u64" instead of "unsigned long" so that this variable is a 64-bit type for both 32-bit and 64-bit machines. It also changes the maximum value returned by clockevent_delta2ns() to KTIME_MAX. Hence this allows a 32-bit machine to sleep for longer than ~2.15 seconds. Please note that this patch also changes "min_delta_ns" to be "u64" too and although this is unnecessary, it makes the patch simpler as it avoids to fixup all callers of clockevent_delta2ns(). [ tglx: changed "unsigned long long" to u64 as we use this data type through out the time code ] Signed-off-by: Jon Hunter <jon-hunter@ti.com> Cc: John Stultz <johnstul@us.ibm.com> LKML-Reference: <1250617512-23567-3-git-send-email-jon-hunter@ti.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-18 11:45:11 -06:00
u64 max_delta_ns;
u64 min_delta_ns;
u32 mult;
u32 shift;
enum clock_event_mode mode;
unsigned int features;
unsigned long retries;
void (*broadcast)(const struct cpumask *mask);
void (*set_mode)(enum clock_event_mode mode,
struct clock_event_device *);
void (*suspend)(struct clock_event_device *);
void (*resume)(struct clock_event_device *);
unsigned long min_delta_ticks;
unsigned long max_delta_ticks;
const char *name;
int rating;
int irq;
const struct cpumask *cpumask;
struct list_head list;
} ____cacheline_aligned;
/*
* Calculate a multiplication factor for scaled math, which is used to convert
* nanoseconds based values to clock ticks:
*
* clock_ticks = (nanoseconds * factor) >> shift.
*
* div_sc is the rearranged equation to calculate a factor from a given clock
* ticks / nanoseconds ratio:
*
* factor = (clock_ticks << shift) / nanoseconds
*/
static inline unsigned long div_sc(unsigned long ticks, unsigned long nsec,
int shift)
{
uint64_t tmp = ((uint64_t)ticks) << shift;
do_div(tmp, nsec);
return (unsigned long) tmp;
}
/* Clock event layer functions */
nohz: Allow 32-bit machines to sleep for more than 2.15 seconds In the dynamic tick code, "max_delta_ns" (member of the "clock_event_device" structure) represents the maximum sleep time that can occur between timer events in nanoseconds. The variable, "max_delta_ns", is defined as an unsigned long which is a 32-bit integer for 32-bit machines and a 64-bit integer for 64-bit machines (if -m64 option is used for gcc). The value of max_delta_ns is set by calling the function "clockevent_delta2ns()" which returns a maximum value of LONG_MAX. For a 32-bit machine LONG_MAX is equal to 0x7fffffff and in nanoseconds this equates to ~2.15 seconds. Hence, the maximum sleep time for a 32-bit machine is ~2.15 seconds, where as for a 64-bit machine it will be many years. This patch changes the type of max_delta_ns to be "u64" instead of "unsigned long" so that this variable is a 64-bit type for both 32-bit and 64-bit machines. It also changes the maximum value returned by clockevent_delta2ns() to KTIME_MAX. Hence this allows a 32-bit machine to sleep for longer than ~2.15 seconds. Please note that this patch also changes "min_delta_ns" to be "u64" too and although this is unnecessary, it makes the patch simpler as it avoids to fixup all callers of clockevent_delta2ns(). [ tglx: changed "unsigned long long" to u64 as we use this data type through out the time code ] Signed-off-by: Jon Hunter <jon-hunter@ti.com> Cc: John Stultz <johnstul@us.ibm.com> LKML-Reference: <1250617512-23567-3-git-send-email-jon-hunter@ti.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2009-08-18 11:45:11 -06:00
extern u64 clockevent_delta2ns(unsigned long latch,
struct clock_event_device *evt);
extern void clockevents_register_device(struct clock_event_device *dev);
extern void clockevents_config(struct clock_event_device *dev, u32 freq);
extern void clockevents_config_and_register(struct clock_event_device *dev,
u32 freq, unsigned long min_delta,
unsigned long max_delta);
extern int clockevents_update_freq(struct clock_event_device *ce, u32 freq);
extern void clockevents_exchange_device(struct clock_event_device *old,
struct clock_event_device *new);
extern void clockevents_set_mode(struct clock_event_device *dev,
enum clock_event_mode mode);
extern int clockevents_register_notifier(struct notifier_block *nb);
extern int clockevents_program_event(struct clock_event_device *dev,
ktime_t expires, bool force);
extern void clockevents_handle_noop(struct clock_event_device *dev);
static inline void
clockevents_calc_mult_shift(struct clock_event_device *ce, u32 freq, u32 minsec)
{
return clocks_calc_mult_shift(&ce->mult, &ce->shift, NSEC_PER_SEC,
freq, minsec);
}
extern void clockevents_suspend(void);
extern void clockevents_resume(void);
#ifdef CONFIG_GENERIC_CLOCKEVENTS
extern void clockevents_notify(unsigned long reason, void *arg);
#else
# define clockevents_notify(reason, arg) do { } while (0)
#endif
#else /* CONFIG_GENERIC_CLOCKEVENTS_BUILD */
static inline void clockevents_suspend(void) {}
static inline void clockevents_resume(void) {}
#define clockevents_notify(reason, arg) do { } while (0)
#endif
#endif