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
|
/* entry.s
*
* This file contains the entry point for the application.
* The name of this entry point is compiler dependent.
* It jumps to the BSP which is responsible for performing
* all initialization.
*
* COPYRIGHT (c) 1989-1999.
* On-Line Applications Research Corporation (OAR).
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.com/license/LICENSE.
*
* $Id$
*/
#include <rtems/asm.h>
BEGIN_CODE
PUBLIC(start) # GNU960 default entry point
SYM(start):
mov 3, r12
modpc r12, r12, r12 # enable tracing/trace faults
mov g5, g5 # NOP
mov 0, g14 # initialize constant for C
/*
* zero out uninitialized data area
*/
zerobss:
lda _end, r4 /* find end of .bss */
lda _bss_start, r5 /* find beginning of .bss */
ldconst 0, r6
loop: st r6, (r5) /* to zero out uninitialized */
addo 4, r5, r5 /* data area */
cmpobl r5, r4, loop /* loop until _end reached */
/* set up stack pointer:
* The heap will begin at '_end'; its length is 'heap_size'
* bytes. The stack will begin at the first 64-byte-aligned
* block after the heap.
*
* A default value of 'heap_size' is set by linking with libnindy.a
* The default can be overridden by redefining this symbol at link
* time (with a line of the form 'heap_size=XXXX;' in the lnk960
* linker specification file; or one of the form
* "-defsym heap_size=XXXX" on the gld960 invocation line).
*/
ldconst _end, sp /* set sp = address of end of heap */
lda heap_size(sp),sp
lda 64(sp), sp /* Now round up to 64-byte boundary */
ldconst 0xffffffc0, r12
and r12, sp, sp
st sp, _stack_start /* Save for brk() routine */
call init_frames
ret /* return to monitor */
init_frames:
mov 0, g14 /* initialize constant for C */
ldconst 0x3b001000, g0
ldconst 0x00009107, g1
modac g1, g0, g0 /* set AC controls */
/*
* remember the frame, so that we can set it up if necessary
*/
st fp, _start_frame
/*
* Call application boot_card.
* Someday, real values of argc and argv will be set up.
* For now, they are set to 0.
*/
ldconst 0,g0
ldconst 0,g1
ldconst 0,g2
call _boot_card
ret
END_CODE
BEGIN_DATA
PUBLIC(_start_frame)
PUBLIC(start_frame)
SYM (_start_frame):
SYM (start_frame):
.word 0 # addr of first user frame: for gdb960
PUBLIC(_stack_start)
PUBLIC(stack_start)
SYM (_stack_start):
SYM (stack_start):
.word 0 # addr of first user frame: for gdb960
END_DATA
BEGIN_BSS
PUBLIC(heap_size)
.set heap_size,0x2000
END_BSS
END
|
