44 lines
1.2 KiB
NASM
44 lines
1.2 KiB
NASM
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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; vulcanOS Kernel ;
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; Developed by Marco 'icebit' Cetica ;
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; (c) 2019-2021 ;
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; Released under GPLv3 ;
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; https://github.com/ice-bit/iceOS ;
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;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
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[BITS 32] ; We should be in protected mode
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section .multiboot
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head_s:
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dd 0xE85250D6 ; Multiboot header magic number
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dd 0 ; Protected mode flag
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dd head_e - head_s ; Header length
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dd 0x100000000 - (0xE85250D6 + 0 + (head_e - head_s)) ; Checksum of above
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; Other flags
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dw 0 ; type
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dw 0 ; flags
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dd 0 ; size
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head_e:
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GLOBAL kernel_loader
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EXTERN kernel_main
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section .text
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kernel_loader:
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mov esp, kernel_stack + KERNEL_STACK_SZ ; Define stack pointer
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push ebx ; Set multiboot header
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call kernel_main ; Jump into kernel's main function
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.loop:
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jmp .loop ; If the kernel returns, go into an infinite loop.
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; This will prevent the CPU to run non-kernel instructions
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; from the memory
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KERNEL_STACK_SZ equ 4096 ; Stack size(4KiB)
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section .bss
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align 4
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kernel_stack:
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resb KERNEL_STACK_SZ ; Reserve 4 KiB
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