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/*
* Copyright (c) 2014 embedded brains GmbH. All rights reserved.
*
* embedded brains GmbH
* Dornierstr. 4
* 82178 Puchheim
* Germany
* <rtems@embedded-brains.de>
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.org/license/LICENSE.
*/
#include <rtems/counter.h>
RTEMS_STATIC_ASSERT(sizeof(rtems_counter_ticks) <= sizeof(uint32_t), type);
static uint64_t to_ns_scaler = UINT64_C(1) << 32;
static uint64_t from_ns_scaler = UINT64_C(1) << 32;
uint64_t rtems_counter_ticks_to_nanoseconds( rtems_counter_ticks counter )
{
return (uint32_t) ((counter * to_ns_scaler) >> 32);
}
rtems_counter_ticks rtems_counter_nanoseconds_to_ticks( uint32_t nanoseconds )
{
return (rtems_counter_ticks) ((nanoseconds * from_ns_scaler) >> 32);
}
void rtems_counter_initialize_converter( uint32_t frequency )
{
uint64_t ns_per_s = UINT64_C(1000000000);
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;
}
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