mirror of
https://github.com/italicsjenga/gba.git
synced 2024-12-23 19:01:30 +11:00
35 lines
724 B
ArmAsm
35 lines
724 B
ArmAsm
.arm
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__start:
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b .Linit
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@ ROM header will be filled in by gbafix
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.fill 188, 1, 0
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.Linit:
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@ set IRQ stack pointer
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mov r0, #0x12
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msr CPSR_cf, r0
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ldr sp, =0x3007fa0
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@ set user stack pointer
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mov r0, #0x1f
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msr CPSR_cf, r0
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ldr sp, =0x3007f00
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@ copy .data section to IWRAM
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ldr r0, =__data_lma @ source address
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ldr r1, =__data_start @ destination address
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ldr r3, =__data_end
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sub r2, r3, r1
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beq .Lskip @ don't try to copy an empty .data section
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add r2, #3
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mov r2, r2, asr #2 @ length (in words)
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add r2, #0x04000000 @ copy by words
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swi 0xb0000
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.Lskip:
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@ jump to user code
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ldr r0, =main
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bx r0
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.pool
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