88 lines
1.3 KiB
ArmAsm
88 lines
1.3 KiB
ArmAsm
.file "startup.S"
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.section .rodata
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.data
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argv0: .asciz "\"This-MIPS-program\""
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argv: .word argv0
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.text
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.section .start, "ax"
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.extern _init
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.extern board_init
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.extern _exc_vect_start
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.extern _xcpt_handler
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.align 2
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.globl _start
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_start:
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.set noreorder
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j init
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nop
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.set reorder
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.text
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.set noreorder
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init:
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# Set stack pointer
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la $sp, stack_ptr
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# Set global pointer
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la $gp, _gp
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# zero bss
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la $8, __bss_start
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la $9, _end
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$zeroise:
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sw $0, 0($8)
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bne $8, $9, $zeroise
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addiu $8, 4
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# Install exception vector jump code
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la $t1, _exc_vect_copy_start
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la $t2, _exc_vect_copy_end
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la $t0, _exc_vect_start
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$install: lw $v0, 0($t1)
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addiu $t1, 4
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sw $v0, 0($t0)
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bne $t1, $t2, $install
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addiu $t0, 4
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# Call _init
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la $k0, _init
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jalr $k0
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nop
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# Call board_init
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la $k0, board_init
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jalr $k0
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nop
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# Set kernel-mode and enable interrupts
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mfc0 $a0, $12
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li $a1, 3
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or $a0, $a1
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mtc0 $a0, $12
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# Set environment
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li $a0, 1
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la $a1, argv
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# Call main
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la $k0, main
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jalr $k0
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nop
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# Terminate after main returns
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_terminate:
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nop
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la $t0, exit
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jalr $t0
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move $a0, $v0
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_exc_vect_copy_start:
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la $k0, _xcpt_handler
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jr $k0
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nop
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_exc_vect_copy_end:
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.set reorder
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