source: rtems/cpukit/score/cpu/no_cpu/cpu.c @ ac7d5ef0

4.104.114.84.95
Last change on this file since ac7d5ef0 was ac7d5ef0, checked in by Joel Sherrill <joel.sherrill@…>, on 05/11/95 at 17:39:37

Initial revision

  • Property mode set to 100644
File size: 3.3 KB
Line 
1/*
2 *  XXX CPU Dependent Source
3 *
4 *
5 *  COPYRIGHT (c) 1989, 1990, 1991, 1992, 1993, 1994.
6 *  On-Line Applications Research Corporation (OAR).
7 *  All rights assigned to U.S. Government, 1994.
8 *
9 *  This material may be reproduced by or for the U.S. Government pursuant
10 *  to the copyright license under the clause at DFARS 252.227-7013.  This
11 *  notice must appear in all copies of this file and its derivatives.
12 *
13 *  $Id$
14 */
15
16#include <rtems/system.h>
17#include <rtems/fatal.h>
18#include <rtems/isr.h>
19#include <rtems/wkspace.h>
20
21/*  _CPU_Initialize
22 *
23 *  This routine performs processor dependent initialization.
24 *
25 *  INPUT PARAMETERS:
26 *    cpu_table       - CPU table to initialize
27 *    thread_dispatch - address of disptaching routine
28 */
29
30
31void _CPU_Initialize(
32  rtems_cpu_table  *cpu_table,
33  void      (*thread_dispatch)      /* ignored on this CPU */
34)
35{
36  if ( cpu_table == NULL )
37    rtems_fatal_error_occurred( RTEMS_NOT_CONFIGURED );
38
39  /*
40   *  The thread_dispatch argument is the address of the entry point
41   *  for the routine called at the end of an ISR once it has been
42   *  decided a context switch is necessary.  On some compilation
43   *  systems it is difficult to call a high-level language routine
44   *  from assembly.  This allows us to trick these systems.
45   *
46   *  If you encounter this problem save the entry point in a CPU
47   *  dependent variable.
48   */
49
50  _CPU_Thread_dispatch_pointer = thread_dispatch;
51
52  /*
53   * XXX; If there is not an easy way to initialize the FP context
54   *      during Context_Initialize, then it is usually easier to
55   *      save an "uninitialized" FP context here and copy it to
56   *      the task's during Context_Initialize.
57   */
58
59  /* XXX: FP context initialization support */
60
61  _CPU_Table = *cpu_table;
62}
63
64/*  _CPU_ISR_install_vector
65 *
66 *  This kernel routine installs the RTEMS handler for the
67 *  specified vector.
68 *
69 *  Input parameters:
70 *    vector      - interrupt vector number
71 *    old_handler - former ISR for this vector number
72 *    new_handler - replacement ISR for this vector number
73 *
74 *  Output parameters:  NONE
75 *
76 */
77
78
79void _CPU_ISR_install_vector(
80  unsigned32  vector,
81  proc_ptr    new_handler,
82  proc_ptr   *old_handler
83)
84{
85   *old_handler = _ISR_Vector_table[ vector ];
86
87   /*
88    *  If the interrupt vector table is a table of pointer to isr entry
89    *  points, then we need to install the appropriate RTEMS interrupt
90    *  handler for this vector number.
91    */
92
93   /*
94    *  We put the actual user ISR address in '_ISR_vector_table'.  This will
95    *  be used by the _ISR_Handler so the user gets control.
96    */
97
98    _ISR_Vector_table[ vector ] = new_handler;
99}
100
101/*PAGE
102 *
103 *  _CPU_Install_interrupt_stack
104 */
105
106void _CPU_Install_interrupt_stack( void )
107{
108}
109
110/*PAGE
111 *
112 *  _CPU_Internal_threads_Idle_thread_body
113 *
114 *  NOTES:
115 *
116 *  1. This is the same as the regular CPU independent algorithm.
117 *
118 *  2. If you implement this using a "halt", "idle", or "shutdown"
119 *     instruction, then don't forget to put it in an infinite loop.
120 *
121 *  3. Be warned. Some processors with onboard DMA have been known
122 *     to stop the DMA if the CPU were put in IDLE mode.  This might
123 *     also be a problem with other on-chip peripherals.  So use this
124 *     hook with caution.
125 */
126
127void _CPU_Internal_threads_Idle_thread_body( void )
128{
129
130  for( ; ; )
131    /* insert your "halt" instruction here */ ;
132}
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