From b9ffb62467daaf4b8f99c05a8c7c84c2dcd3e37f Mon Sep 17 00:00:00 2001 From: Sebastian Huber Date: Fri, 30 Nov 2018 13:57:04 +0100 Subject: Convert CPU counter ticks to/from sbintime_t The sbintime_t is an efficient time format. Add the ability to convert CPU counter ticks to/from sbintime_t. --- cpukit/sapi/src/cpucounterconverter.c | 22 ++++++++++++++++++++-- 1 file changed, 20 insertions(+), 2 deletions(-) (limited to 'cpukit/sapi/src') diff --git a/cpukit/sapi/src/cpucounterconverter.c b/cpukit/sapi/src/cpucounterconverter.c index 12d55362df..7387fe4410 100644 --- a/cpukit/sapi/src/cpucounterconverter.c +++ b/cpukit/sapi/src/cpucounterconverter.c @@ -21,9 +21,13 @@ static uint64_t to_ns_scaler; static uint64_t from_ns_scaler; -uint64_t rtems_counter_ticks_to_nanoseconds( rtems_counter_ticks counter ) +static uint64_t to_sbt_scaler; + +static uint64_t from_sbt_scaler; + +uint64_t rtems_counter_ticks_to_nanoseconds( rtems_counter_ticks ticks ) { - return (uint32_t) ((counter * to_ns_scaler) >> 32); + return (uint32_t) ((ticks * to_ns_scaler) >> 32); } rtems_counter_ticks rtems_counter_nanoseconds_to_ticks( uint32_t nanoseconds ) @@ -31,12 +35,26 @@ rtems_counter_ticks rtems_counter_nanoseconds_to_ticks( uint32_t nanoseconds ) return (rtems_counter_ticks) ((nanoseconds * from_ns_scaler) >> 32); } +int64_t rtems_counter_ticks_to_sbintime( rtems_counter_ticks ticks ) +{ + return (int64_t) ((ticks * to_sbt_scaler) >> 31); +} + +rtems_counter_ticks rtems_counter_sbintime_to_ticks( int64_t sbt ) +{ + return (rtems_counter_ticks) (((uint64_t) sbt * from_sbt_scaler) >> 31); +} + void rtems_counter_initialize_converter( uint32_t frequency ) { uint64_t ns_per_s = UINT64_C(1000000000); + uint64_t bin_per_s = UINT64_C(1) << 32; to_ns_scaler = ((ns_per_s << 32) + frequency - 1) / frequency; from_ns_scaler = ((UINT64_C(1) << 32) * frequency + ns_per_s - 1) / ns_per_s; + + to_sbt_scaler = ((bin_per_s << 31) + frequency - 1) / frequency; + from_sbt_scaler = ((UINT64_C(1) << 31) * frequency + bin_per_s - 1) / bin_per_s; } static void rtems_counter_sysinit( void ) -- cgit v1.2.3