section .data

global gdt

gdt:
    dw .size - 1    ; GDT size
    dd .start       ; GDT start address

  .start:
    ; Null desc
    dq 0

    ; 16-bit code
    dw 0xffff       ; Limit
    dw 0x0000       ; Base (low 16 bits)
    db 0x00         ; Base (mid 8 bits)
    db 10011010b    ; Access
    db 00000000b    ; Granularity
    db 0x00         ; Base (high 8 bits)

    ; 16-bit data
    dw 0xffff       ; Limit
    dw 0x0000       ; Base (low 16 bits)
    db 0x00         ; Base (mid 8 bits)
    db 10010010b    ; Access
    db 00000000b    ; Granularity
    db 0x00         ; Base (high 8 bits)

    ; 32-bit code
    dw 0xffff       ; Limit
    dw 0x0000       ; Base (low 16 bits)
    db 0x00         ; Base (mid 8 bits)
    db 10011010b    ; Access
    db 11001111b    ; Granularity
    db 0x00         ; Base (high 8 bits)

    ; 32-bit data
    dw 0xffff       ; Limit
    dw 0x0000       ; Base (low 16 bits)
    db 0x00         ; Base (mid 8 bits)
    db 10010010b    ; Access
    db 11001111b    ; Granularity
    db 0x00         ; Base (high 8 bits)

    ; 64-bit code
    dw 0x0000       ; Limit
    dw 0x0000       ; Base (low 16 bits)
    db 0x00         ; Base (mid 8 bits)
    db 10011010b    ; Access
    db 00100000b    ; Granularity
    db 0x00         ; Base (high 8 bits)

    ; 64-bit data
    dw 0x0000       ; Limit
    dw 0x0000       ; Base (low 16 bits)
    db 0x00         ; Base (mid 8 bits)
    db 10010010b    ; Access
    db 00000000b    ; Granularity
    db 0x00         ; Base (high 8 bits)

  .end:

  .size: equ .end - .start