40 lines
941 B
ArmAsm
40 lines
941 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 FLAGS, ALIGN | MEMINFO # this is the Multiboot 'flag' field
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.set MAGIC, 0x1BADB002 # 'magic number' lets bootloader find the header
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.set CHECKSUM, -(MAGIC + FLAGS) # checksum of above, to prove we are multiboot
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# Declare a header as in the Multiboot Standard.
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.section .multiboot
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.align 4
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.long MAGIC
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.long FLAGS
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.long CHECKSUM
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# Reserve a stack for the initial thread.
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.section .bss
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.align 16
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stack_bottom:
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.skip 16384 # 16 KiB
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stack_top:
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# The kernel entry point.
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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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# Call the global constructors.
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call _init
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# Transfer control to the main kernel.
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call kernel_main
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# Hang if kernel_main unexpectedly returns.
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cli
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1: hlt
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jmp 1b
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.size _start, . - _start
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