forked from Imagelibrary/rtems
66 lines
1.6 KiB
C
66 lines
1.6 KiB
C
/**
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* @file
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* @brief RTL22xx board Timer driver
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*
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* This uses Timer1 for timing measurments.
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*/
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/*
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* By Ray Xu <rayx.cn@gmail.com>, modify form Mc9328mxl RTEMS DSP
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*
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* The license and distribution terms for this file may be
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* found in the file LICENSE in this distribution or at
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* http://www.rtems.org/license/LICENSE.
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*/
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#include <bsp.h>
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#include <rtems.h>
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#include <rtems/btimer.h>
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#include <lpc22xx.h>
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#include "lpc_timer.h"
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uint32_t g_start;
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uint32_t g_freq;
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bool benchmark_timer_find_average_overhead;
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/*
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* Set up Timer 1
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*/
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void benchmark_timer_initialize( void )
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{
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g_freq = LPC22xx_Fpclk / 1000;
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}
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/*
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* The following controls the behavior of benchmark_timer_read().
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*
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* AVG_OVEREHAD is the overhead for starting and stopping the timer. It
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* is usually deducted from the number returned.
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*
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* LEAST_VALID is the lowest number this routine should trust. Numbers
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* below this are "noise" and zero is returned.
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*/
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#define AVG_OVERHEAD 0 /* It typically takes X.X microseconds */
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/* (Y countdowns) to start/stop the timer. */
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/* This value is in microseconds. */
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#define LEAST_VALID 1 /* Don't trust a clicks value lower than this */
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benchmark_timer_t benchmark_timer_read( void )
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{
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return (T0TC/(LPC22xx_Fpclk/1000000));
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/*
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* Total is calculated by taking into account the number of timer overflow
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* interrupts since the timer was initialized and clicks since the last
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* interrupts.
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*/
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}
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void benchmark_timer_disable_subtracting_average_overhead(bool find_flag)
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{
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benchmark_timer_find_average_overhead = find_flag;
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}
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