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
176
177
178
179
180
181
182
183
184
185
|
/*
* This routine initializes the MC68340/349 Periodic Interval Timer
*
* Based on the `gen68360' board support package, and covered by the
* original distribution terms.
*
* Geoffroy Montel
* France Telecom - CNET/DSM/TAM/CAT
* 4, rue du Clos Courtel
* 35512 CESSON-SEVIGNE
* FRANCE
*
* e-mail: g_montel@yahoo.com
*
* $Id$
*/
/*
* Input parameters: NONE
*
* Output parameters: NONE
*
* 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.
*/
#include <stdlib.h> /* for atexit() */
#include <bsp.h>
#include <rtems/libio.h>
#include <m68340.h>
#define CLOCK_VECTOR 120 /* clock isr routine vector in the vbr */
#define CLOCK_IRQ_LEVEL 6 /* clock isr level */
/*
* Clock_driver_ticks is a monotonically increasing counter of the
* number of clock ticks since the driver was initialized.
*/
volatile rtems_unsigned32 Clock_driver_ticks;
/*
* These are set by clock driver during its init
*/
rtems_device_major_number rtems_clock_major = ~0;
rtems_device_minor_number rtems_clock_minor;
/*
* Periodic interval timer interrupt handler
*/
/******************************************************
Name: Clock_isr
Input parameters: irq vector
Output parameters: none
Description: update # of clock ticks
*****************************************************/
rtems_isr
Clock_isr (rtems_vector_number vector)
{
/*
* Announce the clock tick
*/
Clock_driver_ticks++;
rtems_clock_tick();
}
/******************************************************
Name: clock_exit
Input parameters: -
Output parameters: -
Description: turn off periodic time at shutdown
*****************************************************/
void
Clock_exit (void)
{
if (BSP_Configuration.ticks_per_timeslice ) {
/*
* Turn off periodic interval timer
*/
SIMPITR = 0;
}
}
/******************************************************
Name: Install_clock
Input parameters: the Clock Interrupt Subroutine
Output parameters: -
Description: initialize the periodic interval ticker
called by Clock_Initialize
*****************************************************/
static void
Install_clock (rtems_isr_entry clock_isr)
{
unsigned32 pitr_tmp;
Clock_driver_ticks = 0;
if ( BSP_Configuration.ticks_per_timeslice ) {
set_vector (clock_isr, CLOCK_VECTOR, 1);
/* sets the Periodic Interrupt Control Register PICR */
/* voir a quoi correspond exactement le Clock Vector */
SIMPICR = ( CLOCK_IRQ_LEVEL << 8 ) | ( CLOCK_VECTOR );
/* sets the PITR count value */
/* this assumes a 32.765 kHz crystal */
/* find out whether prescaler should be enabled or not */
if ( BSP_Configuration.microseconds_per_tick <= 31128 ) {
pitr_tmp = ( BSP_Configuration.microseconds_per_tick * 8192 ) / 1000000 ;
}
else {
pitr_tmp = ( BSP_Configuration.microseconds_per_tick / 1000000 ) * 16;
/* enable it */
pitr_tmp |= 0x100;
}
SIMPITR = (unsigned char) pitr_tmp;
atexit (Clock_exit);
}
}
/******************************************************
Name: Clock_initialize
Input parameters: major & minor numbers
Output parameters: -
Description: main entry for clock initialization
calls the bsp dependant routine
*****************************************************/
rtems_device_driver
Clock_initialize(
rtems_device_major_number major,
rtems_device_minor_number minor,
void *pargp
)
{
Install_clock (Clock_isr);
/*
* make major/minor avail to others such as shared memory driver
*/
rtems_clock_major = major;
rtems_clock_minor = minor;
return RTEMS_SUCCESSFUL;
}
/******************************************************
Name: Clock_control
Input parameters: major & minor number
Output parameters:
Description:
*****************************************************/
rtems_device_driver Clock_control(
rtems_device_major_number major,
rtems_device_minor_number minor,
void *pargp
)
{
rtems_unsigned32 isrlevel;
rtems_libio_ioctl_args_t *args = pargp;
if (args) {
/*
* This is hokey, but until we get a defined interface
* to do this, it will just be this simple...
*/
if (args->command == rtems_build_name('I', 'S', 'R', ' ')) {
Clock_isr( CLOCK_VECTOR);
}
else if (args->command == rtems_build_name('N', 'E', 'W', ' ')) {
rtems_interrupt_disable( isrlevel );
(void) set_vector( args->buffer, CLOCK_VECTOR, 1 );
rtems_interrupt_enable( isrlevel );
}
}
return RTEMS_SUCCESSFUL;
}
|
