Move bootloader code to a separate directory

Architecture/i686/Bootstrap/MB2.asm

@@ -0,0 +1,54 @@
+; https://wiki.osdev.org/Higher_Half_x86_Bare_Bones
+; https://wiki.osdev.org/Higher_Half_x86_Bare_Bones_(Backup)
+
+KERNEL_VIRTUAL_BASE equ 0xC0000000 ; 3GB
+KERNEL_STACK_SIZE equ 0x4000 ; 16KB
+
+extern Multiboot2Entry
+extern BootPageTable
+global MB2_start
+
+section .text
+MB2_start:
+	cli
+    mov word [0xb8F00], 0x072E ; .
+
+	mov ecx, (BootPageTable - KERNEL_VIRTUAL_BASE)
+	mov cr3, ecx
+
+    mov word [0xb8F02], 0x072E ; .
+
+	mov ecx, cr4
+	or ecx, 0x00000010 ; Set PSE in CR4
+	mov cr4, ecx
+
+    mov word [0xb8F04], 0x072E ; .
+
+	mov ecx, cr0
+	or ecx, 0x80000000 ; Set PG in CR0
+	mov cr0, ecx
+
+    mov word [0xb8F06], 0x072E ; .
+
+	lea ecx, [HigherHalfStart]
+	jmp ecx
+
+HigherHalfStart:
+    mov word [0xb8F08], 0x072E ; .
+    mov dword [BootPageTable], 0
+    invlpg [0]
+
+	mov esp, KernelStack + KERNEL_STACK_SIZE
+
+	push eax ; Multiboot2 Magic
+	add ebx, KERNEL_VIRTUAL_BASE
+	push ebx ; Multiboot2 Header
+	call Multiboot2Entry
+Loop:
+	hlt
+    jmp Loop
+
+section .bss
+align 16
+KernelStack: 
+	resb KERNEL_STACK_SIZE