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|
.thumb
.syntax unified
.section .text.start
.global _boot_reset
.align 7
_boot_reset:
.word _main_stack_top
.word _start /* reset */
.word _vec_stuck
.word _vec_stuck
.word _vec_stuck
.word _vec_stuck
.word _vec_stuck
.word _vec_stuck
.word _vec_stuck
.word _vec_stuck
.word _vec_stuck
.word _vec_stuck
.word _vec_stuck
.word _vec_stuck
.word _vec_stuck
.word _vec_stuck
.section .data
.global run_table
.align 7
run_table:
.word _main_stack_top
.word _vec_stuck /* reset */
.word _vec_stuck
.word _vec_stuck
.word _vec_stuck
.word _vec_stuck
.word _vec_stuck
.word _vec_stuck
.word _vec_stuck
.word _vec_stuck
.word _vec_stuck
.word _vec_stuck
.word _vec_stuck
.word _vec_stuck
.word _vec_stuck
.word _vec_stuck
.section .text
.global _start
.thumb_func
_start:
/* zero bss */
mov r0, #0
ldr r1, =__bss_start
ldr r2, =__bss_end
_bss_loop:
cmp r1, r2
itt ne
strbne r0, [r1], 1
bne _bss_loop
/* copy data */
ldr r1, =__data_start
ldr r2, =__data_end
ldr r3, =__data_load
_data_loop:
cmp r1, r2
ittt ne
ldrbne r0, [r3], 1
strbne r0, [r1], 1
bne _data_loop
ldr r0, =run_table
ldr r1, =0xe000e000
str r0, [r1, #0xd08] /* VTOR */
mov r0, _proc_stack_top
msr PSP, r0
blx board_setup
blx main
/* fall through to abort() */
.global abort
.thumb_func
abort:
cpsid if
ldr sp, =_main_stack_top
ldr r0, =0x05fa0004 /* reset request */
ldr r1, =0xe000e000
str r0, [r1, #0xd0c] /* AIRCR */
dsb
_stuck:
b _stuck
.thumb_func
_vec_stuck:
mov r0, #'S'
ldr r1, =0x4000c000
str r0, [r1]
mrs r0, IPSR
str r0, [r1]
bl abort
.section .bss
.align 4
.global _main_stack_bot
_main_stack_bot:
.skip 0x400
.global _main_stack_top
_main_stack_top:
.global _proc_stack_bot
_proc_stack_bot:
.skip 0x400
.global _proc_stack_top
_proc_stack_top:
|
