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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 | /* * Copyright (c) 2014-2015 Wind River Systems, Inc. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ /** * @file * @brief Variables needed needed for system clock * * * Declare variables used by both system timer device driver and kernel * components that use timer functionality. */ #ifndef _SYS_CLOCK__H_ #define _SYS_CLOCK__H_ #ifdef __cplusplus extern "C" { #endif #ifndef _ASMLANGUAGE #include <stdint.h> #if defined(CONFIG_SYS_CLOCK_EXISTS) && \ (CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC == 0) #error "SYS_CLOCK_HW_CYCLES_PER_SEC must be non-zero!" #endif #define sys_clock_ticks_per_sec CONFIG_SYS_CLOCK_TICKS_PER_SEC #if defined(CONFIG_TIMER_READS_ITS_FREQUENCY_AT_RUNTIME) extern int sys_clock_hw_cycles_per_sec; #else #define sys_clock_hw_cycles_per_sec CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC #endif /* * sys_clock_us_per_tick global variable represents a number * of microseconds in one OS timer tick */ extern int sys_clock_us_per_tick; /* * sys_clock_hw_cycles_per_tick global variable represents a number * of platform clock ticks in one OS timer tick. * sys_clock_hw_cycles_per_tick often represents a value of divider * of the board clock frequency */ extern int sys_clock_hw_cycles_per_tick; /* number of nsec per usec */ #define NSEC_PER_USEC 1000 /* number of microseconds per millisecond */ #define USEC_PER_MSEC 1000 /* number of milliseconds per second */ #define MSEC_PER_SEC 1000 /* number of microseconds per second */ #define USEC_PER_SEC ((USEC_PER_MSEC) * (MSEC_PER_SEC)) /* number of nanoseconds per second */ #define NSEC_PER_SEC ((NSEC_PER_USEC) * (USEC_PER_MSEC) * (MSEC_PER_SEC)) /* SYS_CLOCK_HW_CYCLES_TO_NS64 converts CPU clock cycles to nanoseconds */ #define SYS_CLOCK_HW_CYCLES_TO_NS64(X) \ (((uint64_t)(X) * sys_clock_us_per_tick * NSEC_PER_USEC) / \ sys_clock_hw_cycles_per_tick) /* * SYS_CLOCK_HW_CYCLES_TO_NS_AVG converts CPU clock cycles to nanoseconds * and calculates the average cycle time */ #define SYS_CLOCK_HW_CYCLES_TO_NS_AVG(X, NCYCLES) \ (uint32_t)(SYS_CLOCK_HW_CYCLES_TO_NS64(X) / NCYCLES) #define SYS_CLOCK_HW_CYCLES_TO_NS(X) (uint32_t)(SYS_CLOCK_HW_CYCLES_TO_NS64(X)) extern int64_t _sys_clock_tick_count; /* * Number of ticks for x seconds. NOTE: With MSEC(), since it does an integer * division, x must be greater or equal to 1000/sys_clock_ticks_per_sec to get * a non-zero value. */ #define SECONDS(x) ((x) * sys_clock_ticks_per_sec) #define MSEC(x) (SECONDS(x) / 1000) #endif /* !_ASMLANGUAGE */ #ifdef __cplusplus } #endif #endif /* _SYS_CLOCK__H_ */ |