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
|
/* SPDX-License-Identifier: BSD-2-Clause */
/*
* This routine initailizes the periodic interrupt timer on
* the Motorola 68332.
*/
/*
* COPYRIGHT (c) 1989-2014.
* On-Line Applications Research Corporation (OAR).
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <stdlib.h>
#include <bsp.h>
#include <mrm332.h>
#include <rtems/clockdrv.h>
#include <rtems/m68k/sim.h>
#define CLOCK_VECTOR MRM_PIV
uint32_t Clock_isrs; /* ISRs until next tick */
volatile uint32_t Clock_driver_ticks; /* ticks since initialization */
static rtems_isr_entry Old_ticker;
static void Clock_exit( void );
static rtems_isr Clock_isr(rtems_vector_number vector)
{
Clock_driver_ticks += 1;
if ( Clock_isrs == 1 ) {
rtems_clock_tick();
Clock_isrs = rtems_configuration_get_microseconds_per_tick() / 1000;
}
else
Clock_isrs -= 1;
}
static void Install_clock(rtems_isr_entry clock_isr)
{
Clock_driver_ticks = 0;
Clock_isrs = rtems_configuration_get_microseconds_per_tick() / 1000;
Old_ticker = (rtems_isr_entry) set_vector( clock_isr, CLOCK_VECTOR, 1 );
/* enable 1mS interrupts */
*PITR = (unsigned short int)( SAM(0x09,0,PITM) );/* load counter */
*PICR = (unsigned short int) /* enable interrupt */
( SAM(ISRL_PIT,8,PIRQL) | SAM(CLOCK_VECTOR,0,PIV) );
atexit( Clock_exit );
}
void Clock_exit( void )
{
/* shutdown the periodic interrupt */
*PICR = (unsigned short int)
( SAM(0,8,PIRQL) | SAM(CLOCK_VECTOR,0,PIV) );
/* ^^ zero disables interrupt */
/* do not restore old vector */
}
void _Clock_Initialize( void )
{
Install_clock( Clock_isr );
}
|
