diff options
author | Richard Cochran <richardcochran@gmail.com> | 2015-01-02 20:22:03 +0100 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2015-01-02 16:47:35 -0500 |
commit | 1891172aa5c32f08ad9931b794edd71e91a4a527 (patch) | |
tree | 176a1a02d34babe34a377d6fb5fd50a78cca3e68 /include/linux/timecounter.h | |
parent | b422da7c366fbf0899db1fdc808fc5fd6700dec5 (diff) |
timecounter: provide a macro to initialize the cyclecounter mask field.
There is no need for users of the timecounter/cyclecounter code to include
clocksource.h just for a single macro.
Signed-off-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/linux/timecounter.h')
-rw-r--r-- | include/linux/timecounter.h | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/include/linux/timecounter.h b/include/linux/timecounter.h index 74f45496e6d1..4382035a75bb 100644 --- a/include/linux/timecounter.h +++ b/include/linux/timecounter.h @@ -19,6 +19,9 @@ #include <linux/types.h> +/* simplify initialization of mask field */ +#define CYCLECOUNTER_MASK(bits) (cycle_t)((bits) < 64 ? ((1ULL<<(bits))-1) : -1) + /** * struct cyclecounter - hardware abstraction for a free running counter * Provides completely state-free accessors to the underlying hardware. @@ -29,7 +32,7 @@ * @read: returns the current cycle value * @mask: bitmask for two's complement * subtraction of non 64 bit counters, - * see CLOCKSOURCE_MASK() helper macro + * see CYCLECOUNTER_MASK() helper macro * @mult: cycle to nanosecond multiplier * @shift: cycle to nanosecond divisor (power of two) */ |