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/* .include "vector_defns.h" */
.section .privileged_code, "ax"
.arm
.weak __mbed_fiq
.weak __mbed_undef
.weak __mbed_prefetch_abort
.weak __mbed_data_abort
.weak __mbed_irq
.weak __mbed_swi
.weak __mbed_dcc_irq
.weak __mbed_reset
.global __mbed_init_realmonitor
/* .global __mbed_init */
__mbed_fiq:
B __mbed_fiq
__mbed_undef:
LDR PC, =0x7fffffa0
__mbed_prefetch_abort:
LDR PC, =0x7fffffb0
__mbed_data_abort:
LDR PC, =0x7fffffc0
__mbed_irq:
MSR CPSR_c, #0x1F|0x80|0x40
STMDB sp!, {r0-r3,r12,lr}
MOV r0, #0xFFFFFF00
LDR r0, [r0]
MOV lr, pc
BX r0
MOV r0, #0xFFFFFF00
STR r0, [r0]
LDMFD sp!,{r0-r3,r12,lr}
MSR CPSR_c, #0x12|0x80|0x40
SUBS pc, lr, #4
__mbed_swi:
STMFD sp!, {a4, r4, ip, lr}
LDR r4, =0x40000040
LDR a4, =0x00940000
LDR PC, =0x7ffff820
__mbed_dcc_irq:
LDMFD sp!,{r0-r3,r12,lr}
MSR CPSR_c, #0x12|0x80|0x40
SUB lr, lr, #4
STMFD sp!, {ip,lr}
LDR LR, =0xfffff000
STR LR, [LR, #0xf00]
LDR PC, =0x7fffffe0
/*
__mbed_reset is called after reset
we setup the stacks and realmonitor, then call Reset_Handler like on M3
*/
.section .text, "ax"
.arm
.global Reset_handler
Reset_Handler:
.extern __libc_init_array
.extern SystemInit
LDR R0, =SystemInit
MOV LR, PC
BX R0
LDR R0, =__libc_init_array
MOV LR, PC
BX R0
LDR R0, =main
BX R0
__mbed_reset:
LDR R0, =( __SRAM_segment_end__ )
MSR CPSR_c, #0x1B|0x80|0x40
MOV SP, R0
SUB R0, R0, #0x00000040
MSR CPSR_c, #0x17|0x80|0x40
MOV SP, R0
SUB R0, R0, #0x00000040
MSR CPSR_c, #0x11|0x80|0x40
MOV SP, R0
SUB R0, R0, #0x00000000
MSR CPSR_c, #0x12|0x80|0x40
MOV SP, R0
SUB R0, R0, #0x00000040
MSR CPSR_c, #0x13|0x80|0x40
MOV SP, R0
SUB R0, R0, #0x00000040
MSR CPSR_c, #0x10
MOV SP, R0
/* Relocate .data section (Copy from ROM to RAM) */
LDR R1, =__text_end__ /* _etext */
LDR R2, =__data_start__ /* _data */
LDR R3, =__data_end__ /* _edata */
CMP R2, R3
BEQ DataIsEmpty
LoopRel: CMP R2, R3
LDRLO R0, [R1], #4
STRLO R0, [R2], #4
BLO LoopRel
DataIsEmpty:
/* Clear .bss section (Zero init) */
MOV R0, #0
LDR R1, =__bss_start__
LDR R2, =__bss_end__
CMP R1,R2
BEQ BSSIsEmpty
LoopZI: CMP R1, R2
STRLO R0, [R1], #4
BLO LoopZI
BSSIsEmpty:
/* Init realmonitor */
LDR R0, =__mbed_init_realmonitor
MOV LR, PC
BX R0
/* Go to Reset_Handler */
LDR R0, =Reset_Handler
BX R0
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