#include <asm/div64.h>
#include <asm/io.h>
-/* clocksource cycle base type */
-typedef u64 cycle_t;
struct clocksource;
struct module;
#endif
/**
- * struct cyclecounter - hardware abstraction for a free running counter
- * Provides completely state-free accessors to the underlying hardware.
- * Depending on which hardware it reads, the cycle counter may wrap
- * around quickly. Locking rules (if necessary) have to be defined
- * by the implementor and user of specific instances of this API.
- *
- * @read: returns the current cycle value
- * @mask: bitmask for two's complement
- * subtraction of non 64 bit counters,
- * see CLOCKSOURCE_MASK() helper macro
- * @mult: cycle to nanosecond multiplier
- * @shift: cycle to nanosecond divisor (power of two)
- */
-struct cyclecounter {
- cycle_t (*read)(const struct cyclecounter *cc);
- cycle_t mask;
- u32 mult;
- u32 shift;
-};
-
-/**
- * struct timecounter - layer above a %struct cyclecounter which counts nanoseconds
- * Contains the state needed by timecounter_read() to detect
- * cycle counter wrap around. Initialize with
- * timecounter_init(). Also used to convert cycle counts into the
- * corresponding nanosecond counts with timecounter_cyc2time(). Users
- * of this code are responsible for initializing the underlying
- * cycle counter hardware, locking issues and reading the time
- * more often than the cycle counter wraps around. The nanosecond
- * counter will only wrap around after ~585 years.
- *
- * @cc: the cycle counter used by this instance
- * @cycle_last: most recent cycle counter value seen by
- * timecounter_read()
- * @nsec: continuously increasing count
- */
-struct timecounter {
- const struct cyclecounter *cc;
- cycle_t cycle_last;
- u64 nsec;
-};
-
-/**
- * cyclecounter_cyc2ns - converts cycle counter cycles to nanoseconds
- * @cc: Pointer to cycle counter.
- * @cycles: Cycles
- *
- * XXX - This could use some mult_lxl_ll() asm optimization. Same code
- * as in cyc2ns, but with unsigned result.
- */
-static inline u64 cyclecounter_cyc2ns(const struct cyclecounter *cc,
- cycle_t cycles)
-{
- u64 ret = (u64)cycles;
- ret = (ret * cc->mult) >> cc->shift;
- return ret;
-}
-
-/**
- * timecounter_init - initialize a time counter
- * @tc: Pointer to time counter which is to be initialized/reset
- * @cc: A cycle counter, ready to be used.
- * @start_tstamp: Arbitrary initial time stamp.
- *
- * After this call the current cycle register (roughly) corresponds to
- * the initial time stamp. Every call to timecounter_read() increments
- * the time stamp counter by the number of elapsed nanoseconds.
- */
-extern void timecounter_init(struct timecounter *tc,
- const struct cyclecounter *cc,
- u64 start_tstamp);
-
-/**
- * timecounter_read - return nanoseconds elapsed since timecounter_init()
- * plus the initial time stamp
- * @tc: Pointer to time counter.
- *
- * In other words, keeps track of time since the same epoch as
- * the function which generated the initial time stamp.
- */
-extern u64 timecounter_read(struct timecounter *tc);
-
-/**
- * timecounter_cyc2time - convert a cycle counter to same
- * time base as values returned by
- * timecounter_read()
- * @tc: Pointer to time counter.
- * @cycle_tstamp: a value returned by tc->cc->read()
- *
- * Cycle counts that are converted correctly as long as they
- * fall into the interval [-1/2 max cycle count, +1/2 max cycle count],
- * with "max cycle count" == cs->mask+1.
- *
- * This allows conversion of cycle counter values which were generated
- * in the past.
- */
-extern u64 timecounter_cyc2time(struct timecounter *tc,
- cycle_t cycle_tstamp);
-
-/**
* struct clocksource - hardware abstraction for a free running counter
* Provides mostly state-free accessors to the underlying hardware.
* This is the structure used for system time.
* @shift: cycle to nanosecond divisor (power of two)
* @max_idle_ns: max idle time permitted by the clocksource (nsecs)
* @maxadj: maximum adjustment value to mult (~11%)
+ * @max_cycles: maximum safe cycle value which won't overflow on multiplication
* @flags: flags describing special properties
* @archdata: arch-specific data
* @suspend: suspend function for the clocksource, if necessary
#ifdef CONFIG_ARCH_CLOCKSOURCE_DATA
struct arch_clocksource_data archdata;
#endif
-
+ u64 max_cycles;
const char *name;
struct list_head list;
int rating;
}
-extern int clocksource_register(struct clocksource*);
extern int clocksource_unregister(struct clocksource*);
extern void clocksource_touch_watchdog(void);
extern struct clocksource* clocksource_get_next(void);
extern void clocksource_mark_unstable(struct clocksource *cs);
extern u64
-clocks_calc_max_nsecs(u32 mult, u32 shift, u32 maxadj, u64 mask);
+clocks_calc_max_nsecs(u32 mult, u32 shift, u32 maxadj, u64 mask, u64 *max_cycles);
extern void
clocks_calc_mult_shift(u32 *mult, u32 *shift, u32 from, u32 to, u32 minsec);
extern int
__clocksource_register_scale(struct clocksource *cs, u32 scale, u32 freq);
extern void
-__clocksource_updatefreq_scale(struct clocksource *cs, u32 scale, u32 freq);
+__clocksource_update_freq_scale(struct clocksource *cs, u32 scale, u32 freq);
+
+/*
+ * Don't call this unless you are a default clocksource
+ * (AKA: jiffies) and absolutely have to.
+ */
+static inline int __clocksource_register(struct clocksource *cs)
+{
+ return __clocksource_register_scale(cs, 1, 0);
+}
static inline int clocksource_register_hz(struct clocksource *cs, u32 hz)
{
return __clocksource_register_scale(cs, 1000, khz);
}
-static inline void __clocksource_updatefreq_hz(struct clocksource *cs, u32 hz)
+static inline void __clocksource_update_freq_hz(struct clocksource *cs, u32 hz)
{
- __clocksource_updatefreq_scale(cs, 1, hz);
+ __clocksource_update_freq_scale(cs, 1, hz);
}
-static inline void __clocksource_updatefreq_khz(struct clocksource *cs, u32 khz)
+static inline void __clocksource_update_freq_khz(struct clocksource *cs, u32 khz)
{
- __clocksource_updatefreq_scale(cs, 1000, khz);
+ __clocksource_update_freq_scale(cs, 1000, khz);
}
static inline void clocksource_of_init(void) {}
#endif
+#ifdef CONFIG_ACPI
+void acpi_generic_timer_init(void);
+#else
+static inline void acpi_generic_timer_init(void) { }
+#endif
+
#endif /* _LINUX_CLOCKSOURCE_H */
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