OpenCores
URL https://opencores.org/ocsvn/openrisc/openrisc/trunk

Subversion Repositories openrisc

[/] [openrisc/] [trunk/] [rtos/] [freertos-6.1.1/] [Demo/] [ARM7_LPC2368_Eclipse/] [RTOSDemo/] [boot.s] - Blame information for rev 867

Go to most recent revision | Details | Compare with Previous | View Log

Line No. Rev Author Line
1 577 jeremybenn
        /* Sample initialization file */
2
 
3
        .extern main
4
        .extern exit
5
 
6
        .text
7
        .code 32
8
 
9
 
10
        .align  0
11
 
12
        .extern __bss_beg__
13
        .extern __bss_end__
14
        .extern __stack_end__
15
        .extern __data_beg__
16
        .extern __data_end__
17
        .extern __data+beg_src__
18
 
19
        .global start
20
        .global endless_loop
21
 
22
        /* Stack Sizes */
23
    .set  UND_STACK_SIZE, 0x00000004
24
    .set  ABT_STACK_SIZE, 0x00000004
25
    .set  FIQ_STACK_SIZE, 0x00000004
26
    .set  IRQ_STACK_SIZE, 0X00000100
27
    .set  SVC_STACK_SIZE, 0x00000100
28
 
29
        /* Standard definitions of Mode bits and Interrupt (I & F) flags in PSRs */
30
    .set  MODE_USR, 0x10            /* User Mode */
31
    .set  MODE_FIQ, 0x11            /* FIQ Mode */
32
    .set  MODE_IRQ, 0x12            /* IRQ Mode */
33
    .set  MODE_SVC, 0x13            /* Supervisor Mode */
34
    .set  MODE_ABT, 0x17            /* Abort Mode */
35
    .set  MODE_UND, 0x1B            /* Undefined Mode */
36
    .set  MODE_SYS, 0x1F            /* System Mode */
37
 
38
    .equ  I_BIT, 0x80               /* when I bit is set, IRQ is disabled */
39
    .equ  F_BIT, 0x40               /* when F bit is set, FIQ is disabled */
40
 
41
 
42
start:
43
_start:
44
_mainCRTStartup:
45
 
46
        /* Setup a stack for each mode - note that this only sets up a usable stack
47
        for system/user, SWI and IRQ modes.   Also each mode is setup with
48
        interrupts initially disabled. */
49
    ldr   r0, .LC6
50
    msr   CPSR_c, #MODE_UND|I_BIT|F_BIT /* Undefined Instruction Mode */
51
    mov   sp, r0
52
    sub   r0, r0, #UND_STACK_SIZE
53
    msr   CPSR_c, #MODE_ABT|I_BIT|F_BIT /* Abort Mode */
54
    mov   sp, r0
55
    sub   r0, r0, #ABT_STACK_SIZE
56
    msr   CPSR_c, #MODE_FIQ|I_BIT|F_BIT /* FIQ Mode */
57
    mov   sp, r0
58
    sub   r0, r0, #FIQ_STACK_SIZE
59
    msr   CPSR_c, #MODE_IRQ|I_BIT|F_BIT /* IRQ Mode */
60
    mov   sp, r0
61
    sub   r0, r0, #IRQ_STACK_SIZE
62
    msr   CPSR_c, #MODE_SVC|I_BIT|F_BIT /* Supervisor Mode */
63
    mov   sp, r0
64
    sub   r0, r0, #SVC_STACK_SIZE
65
    msr   CPSR_c, #MODE_SYS|I_BIT|F_BIT /* System Mode */
66
    mov   sp, r0
67
 
68
        /* We want to start in supervisor mode.  Operation will switch to system
69
        mode when the first task starts. */
70
        msr   CPSR_c, #MODE_SVC|I_BIT|F_BIT
71
 
72
        /* Clear BSS. */
73
 
74
        mov     a2, #0                   /* Fill value */
75
        mov             fp, a2                  /* Null frame pointer */
76
        mov             r7, a2                  /* Null frame pointer for Thumb */
77
 
78
        ldr             r1, .LC1                /* Start of memory block */
79
        ldr             r3, .LC2                /* End of memory block */
80
        subs    r3, r3, r1      /* Length of block */
81
        beq             .end_clear_loop
82
        mov             r2, #0
83
 
84
.clear_loop:
85
        strb    r2, [r1], #1
86
        subs    r3, r3, #1
87
        bgt             .clear_loop
88
 
89
.end_clear_loop:
90
 
91
        /* Initialise data. */
92
 
93
        ldr             r1, .LC3                /* Start of memory block */
94
        ldr             r2, .LC4                /* End of memory block */
95
        ldr             r3, .LC5
96
        subs    r3, r3, r1              /* Length of block */
97
        beq             .end_set_loop
98
 
99
.set_loop:
100
        ldrb    r4, [r2], #1
101
        strb    r4, [r1], #1
102
        subs    r3, r3, #1
103
        bgt             .set_loop
104
 
105
.end_set_loop:
106
 
107
        mov             r0, #0          /* no arguments  */
108
        mov             r1, #0          /* no argv either */
109
 
110
        bl              main
111
 
112
endless_loop:
113
        b               endless_loop
114
 
115
 
116
        .align 0
117
 
118
        .LC1:
119
        .word   __bss_beg__
120
        .LC2:
121
        .word   __bss_end__
122
        .LC3:
123
        .word   __data_beg__
124
        .LC4:
125
        .word   __data_beg_src__
126
        .LC5:
127
        .word   __data_end__
128
        .LC6:
129
        .word   __stack_end__
130
 
131
 
132
        /* Setup vector table.  Note that undf, pabt, dabt, fiq just execute
133
        a null loop. */
134
 
135
.section .startup,"ax"
136
         .code 32
137
         .align 0
138
 
139
        b     _start                                            /* reset - _start                       */
140
        ldr   pc, _undf                                         /* undefined - _undf            */
141
        ldr   pc, _swi                                          /* SWI - _swi                           */
142
        ldr   pc, _pabt                                         /* program abort - _pabt        */
143
        ldr   pc, _dabt                                         /* data abort - _dabt           */
144
        nop                                                                     /* reserved                                     */
145
        ldr   pc, [pc,#-0x120]                          /* IRQ - read the VIC           */
146
        ldr   pc, _fiq                                          /* FIQ - _fiq                           */
147
 
148
_undf:  .word __undf                    /* undefined                            */
149
_swi:   .word vPortYieldProcessor       /* SWI                                          */
150
_pabt:  .word __pabt                    /* program abort                        */
151
_dabt:  .word __dabt                    /* data abort                           */
152
_fiq:   .word __fiq                     /* FIQ                                          */
153
 
154
__undf: b     .                         /* undefined                            */
155
__pabt: b     .                         /* program abort                        */
156
__dabt: b     .                         /* data abort                           */
157
__fiq:  b     .                         /* FIQ                                          */

powered by: WebSVN 2.1.0

© copyright 1999-2024 OpenCores.org, equivalent to Oliscience, all rights reserved. OpenCores®, registered trademark.