mirror of
https://github.com/ApfelTeeSaft/Shard.git
synced 2026-08-27 03:43:25 +00:00
53 lines
687 B
NASM
53 lines
687 B
NASM
BITS 16
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ORG 0x7C00
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start:
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cli
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xor ax, ax
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mov ds, ax
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mov es, ax
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mov ss, ax
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mov sp, 0x7C00
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lgdt [gdt_descriptor]
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in al, 0x92
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or al, 00000010b
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out 0x92, al
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mov eax, cr0
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or eax, 1
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mov cr0, eax
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jmp 0x08:protected_mode
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BITS 32
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protected_mode:
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mov ax, 0x10
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mov ds, ax
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mov es, ax
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mov fs, ax
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mov gs, ax
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mov ss, ax
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mov esp, 0x9C00
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extern kernel_main
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call kernel_main
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halt:
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hlt
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jmp halt
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gdt_start:
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dq 0x0000000000000000
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dq 0x00CF9A000000FFFF
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dq 0x00CF92000000FFFF
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gdt_end:
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gdt_descriptor:
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dw gdt_end - gdt_start - 1
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dd gdt_start
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TIMES 510 - ($-$$) db 0
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DW 0xAA55 |