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
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
|
/*
* Timer Init
*
* This module initializes TIMER 2 for on the MCF5206E for benchmarks.
*
* Copyright (C) 2000 OKTET Ltd., St.-Petersburg, Russia
* Author: Victor V. Vengerov <vvv@oktet.ru>
*
* Based on work:
* Author:
* David Fiddes, D.J@fiddes.surfaid.org
* http://www.calm.hw.ac.uk/davidf/coldfire/
*
* COPYRIGHT (c) 1989-1998.
* On-Line Applications Research Corporation (OAR).
* Copyright assigned to U.S. Government, 1994.
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
*
* http://www.OARcorp.com/rtems/license.html.
*
* $Id$
*/
#include <rtems.h>
#include <bsp.h>
#include "mcf5206/mcf5206e.h"
#define TRR2_VAL 65530
rtems_unsigned32 Timer_interrupts;
rtems_boolean Timer_driver_Find_average_overhead;
/* External assembler interrupt handler routine */
extern rtems_isr timerisr(rtems_vector_number vector);
/* Timer_initialize --
* Initialize timer 2 for accurate time measurement.
*
* PARAMETERS:
* none
*
* RETURNS:
* none
*/
void
Timer_initialize(void)
{
/* Catch timer2 interrupts */
set_vector(timerisr, BSP_INTVEC_TIMER2, 0);
/* Initialize interrupts for timer2 */
*MCF5206E_ICR(MBAR, MCF5206E_INTR_TIMER_2) =
MCF5206E_ICR_AVEC |
((BSP_INTLVL_TIMER2 << MCF5206E_ICR_IL_S) & MCF5206E_ICR_IL) |
((BSP_INTPRIO_TIMER2 << MCF5206E_ICR_IP_S) & MCF5206E_ICR_IP);
/* Enable interrupts from timer2 */
*MCF5206E_IMR(MBAR) &= ~MCF5206E_INTR_BIT(MCF5206E_INTR_TIMER_2);
/* Reset Timer */
*MCF5206E_TMR(MBAR, 2) = MCF5206E_TMR_RST;
*MCF5206E_TMR(MBAR, 2) = MCF5206E_TMR_ICLK_STOP;
*MCF5206E_TMR(MBAR, 2) = MCF5206E_TMR_RST;
*MCF5206E_TCN(MBAR, 2) = 0; /* Zero timer counter */
Timer_interrupts = 0; /* Clear timer ISR counter */
*MCF5206E_TER(MBAR, 2) = MCF5206E_TER_REF | MCF5206E_TER_CAP; /*clr pend*/
*MCF5206E_TRR(MBAR, 2) = TRR2_VAL - 1;
*MCF5206E_TMR(MBAR, 2) =
(((BSP_SYSTEM_FREQUENCY / 1000000) << MCF5206E_TMR_PS_S) &
MCF5206E_TMR_PS) |
MCF5206E_TMR_CE_NONE | MCF5206E_TMR_ORI | MCF5206E_TMR_FRR |
MCF5206E_TMR_RST;
*MCF5206E_TMR(MBAR, 2) |= MCF5206E_TMR_ICLK_MSCLK;
}
/*
* The following controls the behavior of Read_timer().
*
* FIND_AVG_OVERHEAD * instructs the routine to return the "raw" count.
*
* AVG_OVEREHAD is the overhead for starting and stopping the timer. It
* is usually deducted from the number returned.
*
* LEAST_VALID is the lowest number this routine should trust. Numbers
* below this are "noise" and zero is returned.
*/
#define AVG_OVERHEAD 0 /* It typically takes 2.0 microseconds */
/* (Y countdowns) to start/stop the timer. */
/* This value is in microseconds. */
#define LEAST_VALID 1 /* Don't trust a clicks value lower than this */
/* Read_timer --
* Read timer value in microsecond units since timer start.
*
* PARAMETERS:
* none
*
* RETURNS:
* number of microseconds since timer has been started
*/
int
Read_timer( void )
{
rtems_unsigned16 clicks;
rtems_unsigned32 total;
/*
* Read the timer and see how many clicks it has been since counter
* rolled over.
*/
clicks = *MCF5206E_TCN(MBAR, 2);
/* Stop Timer... */
*MCF5206E_TMR(MBAR, 2) = MCF5206E_TMR_ICLK_STOP |
MCF5206E_TMR_RST;
/*
* Total is calculated by taking into account the number of timer
* overflow interrupts since the timer was initialized and clicks
* since the last interrupts.
*/
total = (Timer_interrupts * TRR2_VAL) + clicks;
if ( Timer_driver_Find_average_overhead == 1 )
return total; /* in XXX microsecond units */
if ( total < LEAST_VALID )
return 0; /* below timer resolution */
/*
* Return the count in microseconds
*/
return (total - AVG_OVERHEAD);
}
/* Empty_function --
* Empty function call used in loops to measure basic cost of looping
* in Timing Test Suite.
*
* PARAMETERS:
* none
*
* RETURNS:
* RTEMS_SUCCESSFUL
*/
rtems_status_code
Empty_function(void)
{
return RTEMS_SUCCESSFUL;
}
/* Set_find_average_overhead --
* This routine is invoked by the "Check Timer" (tmck) test in the
* RTEMS Timing Test Suite. It makes the Read_timer routine not
* subtract the overhead required to initialize and read the benchmark
* timer.
*
* PARAMETERS:
* find_flag - boolean flag, TRUE if overhead must not be subtracted.
*
* RETURNS:
* none
*/
void
Set_find_average_overhead(rtems_boolean find_flag)
{
Timer_driver_Find_average_overhead = find_flag;
}
|
