47 lines
879 B
ArmAsm
47 lines
879 B
ArmAsm
# Declare constants for the multiboot header
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.set ALIGN, 1<<0 # align loaded modules on page boundaries
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.set MEMINFO, 1<<1 # provide memory map
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.set VIDEOINFO, 1<<2 # provide video info
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.set MB_FLAGS, ALIGN | MEMINFO | VIDEOINFO # this is the Multiboot 'flag' field
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.set MB_MAGIC, 0x1BADB002 # 'magic number' lets bootloader find the header
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.set MB_CHECKSUM, -(MB_MAGIC + MB_FLAGS) #checksum of above, to prove we are multiboot
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# Multiboot header
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.section .multiboot
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.align 4
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.long MB_MAGIC
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.long MB_FLAGS
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.long MB_CHECKSUM
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.skip 20
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.long 0
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.long 800
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.long 600
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.long 32
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# Create stack
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.section .bss
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stack_bottom:
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.skip 16384 # 16 KiB
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stack_top:
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.section .text
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.global _start
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.type _start, @function
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_start:
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movl $stack_top, %esp
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pushl %eax
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pushl %ebx
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call _init
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call kernel_main
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cli
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1:
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hlt
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jmp 1b
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.size _start, . - _start
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