[00717a3] | 1 | /* |
---|
| 2 | * Timer Init |
---|
| 3 | * |
---|
| 4 | * This module initializes TIMER 2 for on the MCF5206E for benchmarks. |
---|
| 5 | * |
---|
| 6 | * Copyright (C) 2000 OKTET Ltd., St.-Petersburg, Russia |
---|
| 7 | * Author: Victor V. Vengerov <vvv@oktet.ru> |
---|
| 8 | * |
---|
| 9 | * Based on work: |
---|
| 10 | * Author: |
---|
| 11 | * David Fiddes, D.J@fiddes.surfaid.org |
---|
| 12 | * http://www.calm.hw.ac.uk/davidf/coldfire/ |
---|
| 13 | * |
---|
| 14 | * COPYRIGHT (c) 1989-1998. |
---|
| 15 | * On-Line Applications Research Corporation (OAR). |
---|
| 16 | * |
---|
| 17 | * The license and distribution terms for this file may be |
---|
| 18 | * found in the file LICENSE in this distribution or at |
---|
| 19 | * |
---|
[57e9580f] | 20 | * http://www.rtems.com/license/LICENSE. |
---|
[1857b00] | 21 | * |
---|
[00717a3] | 22 | * $Id$ |
---|
| 23 | */ |
---|
| 24 | |
---|
| 25 | #include <rtems.h> |
---|
| 26 | #include <bsp.h> |
---|
| 27 | #include "mcf5206/mcf5206e.h" |
---|
| 28 | |
---|
[1857b00] | 29 | #define TRR2_VAL 65530 |
---|
[00717a3] | 30 | |
---|
[8bc4430b] | 31 | uint32_t Timer_interrupts; |
---|
[00717a3] | 32 | |
---|
[3551166d] | 33 | bool benchmark_timer_find_average_overhead; |
---|
[00717a3] | 34 | |
---|
| 35 | /* External assembler interrupt handler routine */ |
---|
| 36 | extern rtems_isr timerisr(rtems_vector_number vector); |
---|
| 37 | |
---|
| 38 | |
---|
[a5cd2271] | 39 | /* benchmark_timer_initialize -- |
---|
[00717a3] | 40 | * Initialize timer 2 for accurate time measurement. |
---|
| 41 | * |
---|
| 42 | * PARAMETERS: |
---|
| 43 | * none |
---|
| 44 | * |
---|
| 45 | * RETURNS: |
---|
| 46 | * none |
---|
| 47 | */ |
---|
| 48 | void |
---|
[a5cd2271] | 49 | benchmark_timer_initialize(void) |
---|
[00717a3] | 50 | { |
---|
| 51 | /* Catch timer2 interrupts */ |
---|
| 52 | set_vector(timerisr, BSP_INTVEC_TIMER2, 0); |
---|
[1857b00] | 53 | |
---|
[00717a3] | 54 | /* Initialize interrupts for timer2 */ |
---|
| 55 | *MCF5206E_ICR(MBAR, MCF5206E_INTR_TIMER_2) = |
---|
| 56 | MCF5206E_ICR_AVEC | |
---|
| 57 | ((BSP_INTLVL_TIMER2 << MCF5206E_ICR_IL_S) & MCF5206E_ICR_IL) | |
---|
| 58 | ((BSP_INTPRIO_TIMER2 << MCF5206E_ICR_IP_S) & MCF5206E_ICR_IP); |
---|
[1857b00] | 59 | |
---|
[00717a3] | 60 | /* Enable interrupts from timer2 */ |
---|
| 61 | *MCF5206E_IMR(MBAR) &= ~MCF5206E_INTR_BIT(MCF5206E_INTR_TIMER_2); |
---|
[1857b00] | 62 | |
---|
[00717a3] | 63 | /* Reset Timer */ |
---|
| 64 | *MCF5206E_TMR(MBAR, 2) = MCF5206E_TMR_RST; |
---|
| 65 | *MCF5206E_TMR(MBAR, 2) = MCF5206E_TMR_ICLK_STOP; |
---|
| 66 | *MCF5206E_TMR(MBAR, 2) = MCF5206E_TMR_RST; |
---|
| 67 | *MCF5206E_TCN(MBAR, 2) = 0; /* Zero timer counter */ |
---|
| 68 | Timer_interrupts = 0; /* Clear timer ISR counter */ |
---|
| 69 | *MCF5206E_TER(MBAR, 2) = MCF5206E_TER_REF | MCF5206E_TER_CAP; /*clr pend*/ |
---|
| 70 | *MCF5206E_TRR(MBAR, 2) = TRR2_VAL - 1; |
---|
| 71 | *MCF5206E_TMR(MBAR, 2) = |
---|
| 72 | (((BSP_SYSTEM_FREQUENCY / 1000000) << MCF5206E_TMR_PS_S) & |
---|
| 73 | MCF5206E_TMR_PS) | |
---|
| 74 | MCF5206E_TMR_CE_NONE | MCF5206E_TMR_ORI | MCF5206E_TMR_FRR | |
---|
| 75 | MCF5206E_TMR_RST; |
---|
| 76 | *MCF5206E_TMR(MBAR, 2) |= MCF5206E_TMR_ICLK_MSCLK; |
---|
| 77 | } |
---|
| 78 | |
---|
| 79 | /* |
---|
[a5cd2271] | 80 | * The following controls the behavior of benchmark_timer_read(). |
---|
[00717a3] | 81 | * |
---|
| 82 | * FIND_AVG_OVERHEAD * instructs the routine to return the "raw" count. |
---|
| 83 | * |
---|
| 84 | * AVG_OVEREHAD is the overhead for starting and stopping the timer. It |
---|
| 85 | * is usually deducted from the number returned. |
---|
| 86 | * |
---|
| 87 | * LEAST_VALID is the lowest number this routine should trust. Numbers |
---|
| 88 | * below this are "noise" and zero is returned. |
---|
| 89 | */ |
---|
| 90 | |
---|
| 91 | #define AVG_OVERHEAD 0 /* It typically takes 2.0 microseconds */ |
---|
| 92 | /* (Y countdowns) to start/stop the timer. */ |
---|
| 93 | /* This value is in microseconds. */ |
---|
| 94 | #define LEAST_VALID 1 /* Don't trust a clicks value lower than this */ |
---|
| 95 | |
---|
[a5cd2271] | 96 | /* benchmark_timer_read -- |
---|
[00717a3] | 97 | * Read timer value in microsecond units since timer start. |
---|
| 98 | * |
---|
| 99 | * PARAMETERS: |
---|
| 100 | * none |
---|
| 101 | * |
---|
| 102 | * RETURNS: |
---|
| 103 | * number of microseconds since timer has been started |
---|
| 104 | */ |
---|
| 105 | int |
---|
[a5cd2271] | 106 | benchmark_timer_read( void ) |
---|
[00717a3] | 107 | { |
---|
[8bc4430b] | 108 | uint16_t clicks; |
---|
| 109 | uint32_t total; |
---|
[00717a3] | 110 | |
---|
| 111 | /* |
---|
| 112 | * Read the timer and see how many clicks it has been since counter |
---|
| 113 | * rolled over. |
---|
| 114 | */ |
---|
| 115 | clicks = *MCF5206E_TCN(MBAR, 2); |
---|
[1857b00] | 116 | |
---|
[00717a3] | 117 | /* Stop Timer... */ |
---|
| 118 | *MCF5206E_TMR(MBAR, 2) = MCF5206E_TMR_ICLK_STOP | |
---|
| 119 | MCF5206E_TMR_RST; |
---|
| 120 | |
---|
| 121 | /* |
---|
[1857b00] | 122 | * Total is calculated by taking into account the number of timer |
---|
[00717a3] | 123 | * overflow interrupts since the timer was initialized and clicks |
---|
| 124 | * since the last interrupts. |
---|
| 125 | */ |
---|
| 126 | |
---|
| 127 | total = (Timer_interrupts * TRR2_VAL) + clicks; |
---|
| 128 | |
---|
[a5cd2271] | 129 | if ( benchmark_timer_find_average_overhead == 1 ) |
---|
[00717a3] | 130 | return total; /* in XXX microsecond units */ |
---|
| 131 | |
---|
| 132 | if ( total < LEAST_VALID ) |
---|
| 133 | return 0; /* below timer resolution */ |
---|
| 134 | |
---|
| 135 | /* |
---|
| 136 | * Return the count in microseconds |
---|
| 137 | */ |
---|
| 138 | return (total - AVG_OVERHEAD); |
---|
| 139 | } |
---|
| 140 | |
---|
[a5cd2271] | 141 | /* benchmark_timer_disable_subtracting_average_overhead -- |
---|
[00717a3] | 142 | * This routine is invoked by the "Check Timer" (tmck) test in the |
---|
[a5cd2271] | 143 | * RTEMS Timing Test Suite. It makes the benchmark_timer_read routine not |
---|
[00717a3] | 144 | * subtract the overhead required to initialize and read the benchmark |
---|
| 145 | * timer. |
---|
| 146 | * |
---|
| 147 | * PARAMETERS: |
---|
[3551166d] | 148 | * find_flag - boolean flag, true if overhead must not be subtracted. |
---|
[00717a3] | 149 | * |
---|
| 150 | * RETURNS: |
---|
| 151 | * none |
---|
| 152 | */ |
---|
| 153 | void |
---|
[3551166d] | 154 | benchmark_timer_disable_subtracting_average_overhead(bool find_flag) |
---|
[00717a3] | 155 | { |
---|
[a5cd2271] | 156 | benchmark_timer_find_average_overhead = find_flag; |
---|
[00717a3] | 157 | } |
---|