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-rw-r--r--kernel/time/clocksource.c76
1 files changed, 0 insertions, 76 deletions
diff --git a/kernel/time/clocksource.c b/kernel/time/clocksource.c
index b79f39bda7e1..4892352f0e49 100644
--- a/kernel/time/clocksource.c
+++ b/kernel/time/clocksource.c
@@ -34,82 +34,6 @@
34#include "tick-internal.h" 34#include "tick-internal.h"
35#include "timekeeping_internal.h" 35#include "timekeeping_internal.h"
36 36
37void timecounter_init(struct timecounter *tc,
38 const struct cyclecounter *cc,
39 u64 start_tstamp)
40{
41 tc->cc = cc;
42 tc->cycle_last = cc->read(cc);
43 tc->nsec = start_tstamp;
44}
45EXPORT_SYMBOL_GPL(timecounter_init);
46
47/**
48 * timecounter_read_delta - get nanoseconds since last call of this function
49 * @tc: Pointer to time counter
50 *
51 * When the underlying cycle counter runs over, this will be handled
52 * correctly as long as it does not run over more than once between
53 * calls.
54 *
55 * The first call to this function for a new time counter initializes
56 * the time tracking and returns an undefined result.
57 */
58static u64 timecounter_read_delta(struct timecounter *tc)
59{
60 cycle_t cycle_now, cycle_delta;
61 u64 ns_offset;
62
63 /* read cycle counter: */
64 cycle_now = tc->cc->read(tc->cc);
65
66 /* calculate the delta since the last timecounter_read_delta(): */
67 cycle_delta = (cycle_now - tc->cycle_last) & tc->cc->mask;
68
69 /* convert to nanoseconds: */
70 ns_offset = cyclecounter_cyc2ns(tc->cc, cycle_delta);
71
72 /* update time stamp of timecounter_read_delta() call: */
73 tc->cycle_last = cycle_now;
74
75 return ns_offset;
76}
77
78u64 timecounter_read(struct timecounter *tc)
79{
80 u64 nsec;
81
82 /* increment time by nanoseconds since last call */
83 nsec = timecounter_read_delta(tc);
84 nsec += tc->nsec;
85 tc->nsec = nsec;
86
87 return nsec;
88}
89EXPORT_SYMBOL_GPL(timecounter_read);
90
91u64 timecounter_cyc2time(struct timecounter *tc,
92 cycle_t cycle_tstamp)
93{
94 u64 cycle_delta = (cycle_tstamp - tc->cycle_last) & tc->cc->mask;
95 u64 nsec;
96
97 /*
98 * Instead of always treating cycle_tstamp as more recent
99 * than tc->cycle_last, detect when it is too far in the
100 * future and treat it as old time stamp instead.
101 */
102 if (cycle_delta > tc->cc->mask / 2) {
103 cycle_delta = (tc->cycle_last - cycle_tstamp) & tc->cc->mask;
104 nsec = tc->nsec - cyclecounter_cyc2ns(tc->cc, cycle_delta);
105 } else {
106 nsec = cyclecounter_cyc2ns(tc->cc, cycle_delta) + tc->nsec;
107 }
108
109 return nsec;
110}
111EXPORT_SYMBOL_GPL(timecounter_cyc2time);
112
113/** 37/**
114 * clocks_calc_mult_shift - calculate mult/shift factors for scaled math of clocks 38 * clocks_calc_mult_shift - calculate mult/shift factors for scaled math of clocks
115 * @mult: pointer to mult variable 39 * @mult: pointer to mult variable