source: rtems/c/src/lib/libbsp/i386/force386/clock/ckinit.c @ 9700578

4.104.114.84.95
Last change on this file since 9700578 was 9700578, checked in by Joel Sherrill <joel.sherrill@…>, on Oct 30, 1995 at 9:54:45 PM

SPARC port passes all tests

  • Property mode set to 100644
File size: 3.1 KB
Line 
1/*  Clock_initialize
2 *
3 *  This routine initializes the Motorola MFP 68901 on the
4 *  FORCE CPU386 board.  The tick frequency is 1 millisecond.
5 *
6 *  Input parameters:  NONE
7 *
8 *  Output parameters:  NONE
9 *
10 *  COPYRIGHT (c) 1989, 1990, 1991, 1992, 1993, 1994.
11 *  On-Line Applications Research Corporation (OAR).
12 *  All rights assigned to U.S. Government, 1994.
13 *
14 *  This material may be reproduced by or for the U.S. Government pursuant
15 *  to the copyright license under the clause at DFARS 252.227-7013.  This
16 *  notice must appear in all copies of this file and its derivatives.
17 *
18 *  $Id$
19 */
20
21#include <bsp.h>
22
23#include <rtems/libio.h>
24
25#include <stdlib.h>
26
27#define CLOCK_VECTOR  0x38
28
29rtems_unsigned32 Clock_isrs;              /* ISRs until next tick */
30
31volatile rtems_unsigned32 Clock_driver_ticks;
32
33rtems_isr_entry  Old_ticker;
34
35void Clock_exit( void );
36 
37/*
38 * These are set by clock driver during its init
39 */
40 
41rtems_device_major_number rtems_clock_major = ~0;
42rtems_device_major_number rtems_clock_minor = 0;
43
44/*
45 *  This is the ISR handler.
46 */
47
48rtems_isr Clock_isr(
49  rtems_vector_number vector
50)
51{
52  /* enable_tracing(); */
53  Clock_driver_ticks += 1;
54  if ( Clock_isrs == 1 ) {
55    rtems_clock_tick();
56    Clock_isrs = BSP_Configuration.microseconds_per_tick / 1000;
57  }
58  else
59    Clock_isrs -= 1;
60}
61
62void Install_clock(
63  rtems_isr_entry clock_isr
64)
65{
66  Clock_driver_ticks = 0;
67  Clock_isrs = BSP_Configuration.microseconds_per_tick / 1000;
68
69  if ( BSP_Configuration.ticks_per_timeslice ) {
70    Old_ticker = ( rtems_isr_entry ) set_vector( clock_isr, CLOCK_VECTOR, 1 );
71    outport_byte( TBCR, 0x14 );  /* reset it, delay mode, 50X */
72    outport_byte( TBDR, 0x50 );  /* 1 millisecond */
73    outport_byte( IERA, 0x41 );  /* enable interrupt for B */
74  }
75  atexit( Clock_exit );
76}
77
78void Clock_exit( void )
79{
80  if ( BSP_Configuration.ticks_per_timeslice ) {
81    outport_byte( TBCR, 0x00 );  /* initial value */
82    outport_byte( IERA, 0x40 );  /* disable interrupt */
83    /* ??? Is "do not restore old vector" causing problems? */
84  }
85}
86
87rtems_device_driver Clock_initialize(
88  rtems_device_major_number major,
89  rtems_device_minor_number minor,
90  void *pargp
91)
92{
93  Install_clock( Clock_isr );
94 
95  /*
96   * make major/minor avail to others such as shared memory driver
97   */
98 
99  rtems_clock_major = major;
100  rtems_clock_minor = minor;
101 
102  return RTEMS_SUCCESSFUL;
103}
104 
105rtems_device_driver Clock_control(
106  rtems_device_major_number major,
107  rtems_device_minor_number minor,
108  void *pargp
109)
110{
111    rtems_unsigned32 isrlevel;
112    rtems_libio_ioctl_args_t *args = pargp;
113 
114    if (args == 0)
115        goto done;
116 
117    /*
118     * This is hokey, but until we get a defined interface
119     * to do this, it will just be this simple...
120     */
121 
122    if (args->command == rtems_build_name('I', 'S', 'R', ' '))
123    {
124        Clock_isr(CLOCK_VECTOR);
125    }
126    else if (args->command == rtems_build_name('N', 'E', 'W', ' '))
127    {
128      rtems_interrupt_disable( isrlevel );
129       (void) set_vector( args->buffer, CLOCK_VECTOR, 1 );
130      rtems_interrupt_enable( isrlevel );
131    }
132 
133done:
134    return RTEMS_SUCCESSFUL;
135}
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