A poorly written OS for the x86 arch. (WIP)
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; SRs to find memory size and leave it as a "note" for the kernel
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mmap_e820:
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mov di, 0x8004
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mov ebx, 0 ; Must be 0
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mov bp, 0 ; entry count
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mov eax, 0xe820 ; function reg
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mov edx, 'SMAP'
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mov [es:di + 20], dword 1 ; fill
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mov ecx, 24 ; ask for 24 bytes
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int 0x15 ; Do the interupt
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; carry flag = (un)supported function
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jc short mmap_fail
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; TODO more error stuff
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cmp eax, edx
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jne short mmap_fail
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test ebx, ebx
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je short mmap_fail
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mmap_fail:
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stc
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ret
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e820_dt_start:
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e820_low: dd 0
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e820_high: dd 0
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e820_len_low: dd 0
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e820_len_high: dd 0
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e820_type: dd 0
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e820_dt_end:
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