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37 lines
728 B
37 lines
728 B
; Utils
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%include "bootloader/equ/vga.asm"
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%include "bootloader/pm/vga/print.asm"
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; GDT & switching to PM
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%include "bootloader/pm/gdt.asm" ; GDT defined here
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; Switching to PM
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[bits 16]
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pm_preinit:
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cli ; Switch interupts
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lgdt [gdt_descriptor] ; Tell the CPU about the GDT
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mov eax, cr0 ; Set first bit of the CR0 register
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or eax, 0x1 ; to 1
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mov cr0, eax ; Update the control register
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; Initialize PM
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jmp GDT_CODE_SEG:pm_init
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[bits 32]
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; Init registers & stack when in PM
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pm_init:
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mov ax, GDT_DATA_SEG ; Point the segment registers to GDT_DATA_SEG
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; Segment registers
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mov ds, ax
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mov ss, 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 ebp, 0x900000 ; Update the stack pointer
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mov esp, ebp
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call BEGIN_PM
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