50 lines
1.1 KiB
NASM
50 lines
1.1 KiB
NASM
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MAIN_BIOS_AREA_START equ 0xe0000
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; Arguments:
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; -- None --
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acpi_search_rsdp:
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.prolog:
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push esi
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sub esp, 8
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mov esi, esp
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mov [esi], dword 0
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mov [esi + 4], ecx
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.search_loop_header:
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mov ecx, MAIN_BIOS_AREA_START
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.search_loop:
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push ebp
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mov ebp, esp
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push ecx
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push dword .signature
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push dword 8
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call mem_equal
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mov esp, ebp
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pop ebp
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cmp ax, 0
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jne .rsdp_found
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add ecx, 16
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cmp ecx, 0x100000
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jb .search_loop
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; If no "RSD PTR "-signature could be found
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xor ecx, ecx
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.rsdp_found:
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mov eax, ecx
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.epilog:
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mov ecx, [esi + 4]
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add esp, 8
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pop esi
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ret
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.signature:
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db "RSD PTR "
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