A poorly written OS for the x86 arch. (WIP)
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[bits 32] ; 32-bit mode
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PAGING_ENABLE_FLAG equ 0x80000001
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PAGE_DIRECTORY_ADDR equ 0xffffffff ; TODO: change me to something good
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global enable_paging_registers ; make the SR "global" so that we can access it in the kernel etc
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enable_paging_registers:
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push eax
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mov eax, PAGE_DIRECTORY_ADDR ; Move the address of the
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; page register (page directory) into eax
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; (Using eax as a middle-man register)
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mov cr3, eax ; Put the address into the cr3 register (required by the MMU)
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mov eax, cr0 ; eax as a middle-man register (again)
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or eax, PAGING_ENABLE_FLAG ; perform the OR operation on eax (ex: 0b01 or 0b10 = 0b11)
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; This is needed to enable paging (set the flag as "enabled")
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mov cr0, eax ; Move it into cr0 to finally enable paging
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pop eax
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ret ; return to last location
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