40 lines
757 B
ArmAsm
40 lines
757 B
ArmAsm
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# Constants for multiboot
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.set ALIGN, 1<<0 # align on page boundaries
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.set MEMINFO, 1<<1 # memory map
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.set FLAGS, ALIGN | MEMINFO # for multiboot 'flag' field
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.set MAGIC, 0x1BADB002 # magic number for bootloader
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.set CHECKSUM, -(MAGIC + FLAGS) # checksum to prove we're multiboot
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# Declare header for multiboot
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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 stack for 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 # 16K
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stack_top:
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# Kernel entry
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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 global constructors
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call _init
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# Start kernel
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call kern_main
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# Hang if kernel 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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