59 lines
875 B
ArmAsm
59 lines
875 B
ArmAsm
/*
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* Copyright (c) 2018 naehrwert
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*/
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.section .text._start
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.arm
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.extern memset
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.type memset, %function
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.extern ipl_main
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.type ipl_main, %function
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.globl _start
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.type _start, %function
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_start:
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ADR R0, _start
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LDR R1, =__ipl_start
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CMP R0, R1
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BEQ _real_start
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ADR R2, _reloc_ipl
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LDR R3, =0x4003FF00
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MOV R4, #(_real_start - _reloc_ipl)
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_copy_loop:
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LDMIA R2!, {R5}
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STMIA R3!, {R5}
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SUBS R4, #4
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BNE _copy_loop
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LDR R2, =__ipl_end
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SUB R2, R2, R1
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LDR R3, =_real_start
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LDR R4, =0x4003FF00
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BX R4
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_reloc_ipl:
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LDMIA R0!, {R4-R7}
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STMIA R1!, {R4-R7}
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SUBS R2, #0x10
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BNE _reloc_ipl
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BX R3
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_real_start:
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LDR SP, =0x4003FF00
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LDR R0, =__bss_start
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EOR R1, R1, R1
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LDR R2, =__bss_end
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SUB R2, R2, R0
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BL memset
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BL ipl_main
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B .
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.globl pivot_stack
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.type pivot_stack, %function
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pivot_stack:
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MOV SP, R0
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BX LR
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