89 lines
1.5 KiB
NASM
Executable File
89 lines
1.5 KiB
NASM
Executable File
; entry.asm: Entrypoint for the loader partition of the Nightloader.
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; WARNING: Never import at the top of this file!
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; If something has to be included, include it at the bottom!
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STACK_SIZE equ 32768
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UPPER_STACK_POINTER equ 0x100000
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LOWER_STACK_POINTER equ (UPPER_STACK_POINTER - STACK_SIZE)
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bits 16
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org 0xa000
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entry:
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mov ebx, LOWER_STACK_POINTER
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mov ss, ebx
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mov esp, STACK_SIZE
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mov ebp, STACK_SIZE
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push dx
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.check_a20:
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push ebp
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mov ebp, esp
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call check_a20_wraparound
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mov esp, ebp
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pop ebp
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cmp eax, 1
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je .a20_is_enabled
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cli
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hlt
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.a20_is_enabled:
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; jmp .flat_gdt_loaded
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; Reset Display
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mov ah, 0x00
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mov al, 0x03
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int 0x10
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; mov ah, 0x05
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; mov al, 0
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; int 0x10
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mov ah, 0x0b
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mov bh, 0x00
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mov bl, 0
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int 0x10
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push ebp
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mov ebp, esp
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call setup_drivers
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mov esp, ebp
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pop ebp
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mov edi, ebp
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mov esi, esp
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push ebp
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mov ebp, esp
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push .flat_gdt_loaded
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call load_flat_gdt
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mov esp, ebp
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pop ebp
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.flat_gdt_loaded:
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mov ebp, edi
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mov esp, esi
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mov ebx, some_text
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push ebp
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mov ebp, esp
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push dword ebx
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call dword write_text
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mov esp, ebp
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pop ebp
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cli
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hlt
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some_text:
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db "This is some text.", 0x00
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; Utilities
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%include "utility/math.asm"
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%include "utility/memory.asm"
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; Memory Management
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%include "memory/a20.asm"
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%include "memory/gdt.asm"
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; Driver Manager
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; %include "drivers/manager.asm"
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