[deliverable/linux.git] / include / linux / clockchips.h

/*  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

#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_ENTER,
	CLOCK_EVT_NOTIFY_BROADCAST_EXIT,
	CLOCK_EVT_NOTIFY_SUSPEND,
	CLOCK_EVT_NOTIFY_RESUME,
	CLOCK_EVT_NOTIFY_CPU_DEAD,
};

/*
 * Clock event features
 */
#define CLOCK_EVT_FEAT_PERIODIC		0x000001
#define CLOCK_EVT_FEAT_ONESHOT		0x000002
/*
 * 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		0x000004
#define CLOCK_EVT_FEAT_DUMMY		0x000008

/**
 * struct clock_event_device - clock event device descriptor
 * @name:		ptr to clock event name
 * @features:		features
 * @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)
 * @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
 * @set_next_event:	set next event function
 * @set_mode:		set mode function
 * @event_handler:	Assigned by the framework to be called by the low
 *			level handler of the event source
 * @broadcast:		function to broadcast events
 * @list:		list head for the management code
 * @mode:		operating mode assigned by the management code
 * @next_event:		local storage for the next event in oneshot mode
 */
struct clock_event_device {
	const char		*name;
	unsigned int		features;
	unsigned long		max_delta_ns;
	unsigned long		min_delta_ns;
	unsigned long		mult;
	int			shift;
	int			rating;
	int			irq;
	cpumask_t		cpumask;
	int			(*set_next_event)(unsigned long evt,
						  struct clock_event_device *);
	void			(*set_mode)(enum clock_event_mode mode,
					    struct clock_event_device *);
	void			(*event_handler)(struct clock_event_device *);
	void			(*broadcast)(cpumask_t mask);
	struct list_head	list;
	enum clock_event_mode	mode;
	ktime_t			next_event;
};

/*
 * 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 */
extern unsigned long clockevent_delta2ns(unsigned long latch,
					 struct clock_event_device *evt);
extern void clockevents_register_device(struct clock_event_device *dev);

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, ktime_t now);

extern void clockevents_notify(unsigned long reason, void *arg);

#else

static inline void clockevents_resume_events(void) { }
#define clockevents_notify(reason, arg) do { } while (0)

#endif

#endif
Commit	Line	Data
d316c57f TG	1	/* linux/include/linux/clockchips.h
	2	*
	3	* This file contains the structure definitions for clockchips.
	4	*
	5	* If you are not a clockchip, or the time of day code, you should
	6	* not be including this file!
	7	*/
	8	#ifndef _LINUX_CLOCKCHIPS_H
	9	#define _LINUX_CLOCKCHIPS_H
	10
	11	#ifdef CONFIG_GENERIC_CLOCKEVENTS
	12
	13	#include <linux/clocksource.h>
	14	#include <linux/cpumask.h>
	15	#include <linux/ktime.h>
	16	#include <linux/notifier.h>
	17
	18	struct clock_event_device;
	19
	20	/* Clock event mode commands */
	21	enum clock_event_mode {
	22	CLOCK_EVT_MODE_UNUSED = 0,
	23	CLOCK_EVT_MODE_SHUTDOWN,
	24	CLOCK_EVT_MODE_PERIODIC,
	25	CLOCK_EVT_MODE_ONESHOT,
18de5bc4	26	CLOCK_EVT_MODE_RESUME,
d316c57f TG	27	};
	28
	29	/* Clock event notification values */
	30	enum clock_event_nofitiers {
	31	CLOCK_EVT_NOTIFY_ADD,
	32	CLOCK_EVT_NOTIFY_BROADCAST_ON,
	33	CLOCK_EVT_NOTIFY_BROADCAST_OFF,
	34	CLOCK_EVT_NOTIFY_BROADCAST_ENTER,
	35	CLOCK_EVT_NOTIFY_BROADCAST_EXIT,
	36	CLOCK_EVT_NOTIFY_SUSPEND,
	37	CLOCK_EVT_NOTIFY_RESUME,
	38	CLOCK_EVT_NOTIFY_CPU_DEAD,
	39	};
	40
	41	/*
	42	* Clock event features
	43	*/
	44	#define CLOCK_EVT_FEAT_PERIODIC 0x000001
	45	#define CLOCK_EVT_FEAT_ONESHOT 0x000002
	46	/*
	47	* x86(64) specific misfeatures:
	48	*
	49	* - Clockevent source stops in C3 State and needs broadcast support.
	50	* - Local APIC timer is used as a dummy device.
	51	*/
	52	#define CLOCK_EVT_FEAT_C3STOP 0x000004
	53	#define CLOCK_EVT_FEAT_DUMMY 0x000008
	54
	55	/**
	56	* struct clock_event_device - clock event device descriptor
	57	* @name: ptr to clock event name
ce0be127	58	* @features: features
d316c57f TG	59	* @max_delta_ns: maximum delta value in ns
	60	* @min_delta_ns: minimum delta value in ns
	61	* @mult: nanosecond to cycles multiplier
	62	* @shift: nanoseconds to cycles divisor (power of two)
	63	* @rating: variable to rate clock event devices
ce0be127 SS	64	* @irq: IRQ number (only for non CPU local devices)
	65	* @cpumask: cpumask to indicate for which CPUs this device works
	66	* @set_next_event: set next event function
d316c57f	67	* @set_mode: set mode function
ce0be127	68	* @event_handler: Assigned by the framework to be called by the low
d316c57f TG	69	* level handler of the event source
	70	* @broadcast: function to broadcast events
	71	* @list: list head for the management code
	72	* @mode: operating mode assigned by the management code
	73	* @next_event: local storage for the next event in oneshot mode
	74	*/
	75	struct clock_event_device {
	76	const char *name;
	77	unsigned int features;
	78	unsigned long max_delta_ns;
	79	unsigned long min_delta_ns;
	80	unsigned long mult;
	81	int shift;
	82	int rating;
	83	int irq;
	84	cpumask_t cpumask;
	85	int (*set_next_event)(unsigned long evt,
	86	struct clock_event_device *);
	87	void (*set_mode)(enum clock_event_mode mode,
	88	struct clock_event_device *);
	89	void (event_handler)(struct clock_event_device );
	90	void (*broadcast)(cpumask_t mask);
	91	struct list_head list;
	92	enum clock_event_mode mode;
	93	ktime_t next_event;
	94	};
	95
	96	/*
	97	* Calculate a multiplication factor for scaled math, which is used to convert
	98	* nanoseconds based values to clock ticks:
	99	*
	100	* clock_ticks = (nanoseconds * factor) >> shift.
	101	*
	102	* div_sc is the rearranged equation to calculate a factor from a given clock
	103	* ticks / nanoseconds ratio:
	104	*
	105	* factor = (clock_ticks << shift) / nanoseconds
	106	*/
	107	static inline unsigned long div_sc(unsigned long ticks, unsigned long nsec,
	108	int shift)
	109	{
	110	uint64_t tmp = ((uint64_t)ticks) << shift;
	111
	112	do_div(tmp, nsec);
	113	return (unsigned long) tmp;
	114	}
	115
	116	/* Clock event layer functions */
	117	extern unsigned long clockevent_delta2ns(unsigned long latch,
	118	struct clock_event_device *evt);
	119	extern void clockevents_register_device(struct clock_event_device *dev);
	120
	121	extern void clockevents_exchange_device(struct clock_event_device *old,
	122	struct clock_event_device *new);
d316c57f TG	123	extern void clockevents_set_mode(struct clock_event_device *dev,
	124	enum clock_event_mode mode);
	125	extern int clockevents_register_notifier(struct notifier_block *nb);
d316c57f TG	126	extern int clockevents_program_event(struct clock_event_device *dev,
	127	ktime_t expires, ktime_t now);
	128
	129	extern void clockevents_notify(unsigned long reason, void *arg);
	130
	131	#else
	132
	133	static inline void clockevents_resume_events(void) { }
	134	#define clockevents_notify(reason, arg) do { } while (0)
	135
	136	#endif
	137
	138	#endif