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-rw-r--r--include/linux/timex.h15
1 files changed, 15 insertions, 0 deletions
diff --git a/include/linux/timex.h b/include/linux/timex.h
index b3726e61368e..9d3f1a5b6178 100644
--- a/include/linux/timex.h
+++ b/include/linux/timex.h
@@ -64,6 +64,20 @@
64 64
65#include <asm/timex.h> 65#include <asm/timex.h>
66 66
67#ifndef random_get_entropy
68/*
69 * The random_get_entropy() function is used by the /dev/random driver
70 * in order to extract entropy via the relative unpredictability of
71 * when an interrupt takes places versus a high speed, fine-grained
72 * timing source or cycle counter. Since it will be occurred on every
73 * single interrupt, it must have a very low cost/overhead.
74 *
75 * By default we use get_cycles() for this purpose, but individual
76 * architectures may override this in their asm/timex.h header file.
77 */
78#define random_get_entropy() get_cycles()
79#endif
80
67/* 81/*
68 * SHIFT_PLL is used as a dampening factor to define how much we 82 * SHIFT_PLL is used as a dampening factor to define how much we
69 * adjust the frequency correction for a given offset in PLL mode. 83 * adjust the frequency correction for a given offset in PLL mode.
@@ -141,6 +155,7 @@ extern int do_adjtimex(struct timex *);
141extern void hardpps(const struct timespec *, const struct timespec *); 155extern void hardpps(const struct timespec *, const struct timespec *);
142 156
143int read_current_timer(unsigned long *timer_val); 157int read_current_timer(unsigned long *timer_val);
158void ntp_notify_cmos_timer(void);
144 159
145/* The clock frequency of the i8253/i8254 PIT */ 160/* The clock frequency of the i8253/i8254 PIT */
146#define PIT_TICK_RATE 1193182ul 161#define PIT_TICK_RATE 1193182ul