Add GDT and IDT

kernel/include/kernel/GDT.h

@@ -0,0 +1,56 @@
+#pragma once
+
+#include <stdint.h>
+
+union SegmentDesriptor
+{
+	struct
+	{
+		uint16_t	limit_lo;
+		uint16_t	base_lo;
+		uint8_t		base_hi1;
+
+		uint8_t		type			: 4;
+		uint8_t		system			: 1;
+		uint8_t		DPL				: 2;
+		uint8_t		present			: 1;
+
+		uint8_t		limit_hi		: 4;
+		uint8_t		flags			: 4;
+
+		uint8_t		base_hi2;
+	};
+	
+	struct
+	{
+		uint32_t low;
+		uint32_t high;
+	};
+
+	SegmentDesriptor() : low(0), high(0) {}
+	SegmentDesriptor(uint32_t base, uint32_t limit, uint8_t access, uint8_t _flags)
+		: low(0), high(0)
+	{
+		set_base(base);
+		set_limit(limit);
+
+		high |= ((uint16_t)access) << 8;
+		flags = _flags;
+	}
+
+	void set_base(uint32_t base)
+	{
+		base_lo  =  base        & 0xFFFF;
+		base_hi1 = (base >> 16) & 0x00FF;
+		base_hi2 = (base >> 24) & 0x00FF;
+	}
+
+	void set_limit(uint32_t limit)
+	{
+		limit_lo =  limit        & 0xFFFF;
+		limit_hi = (limit >> 16) & 0x00FF;
+	}
+
+} __attribute__((packed));
+
+void gdt_initialize();

kernel/include/kernel/IDT.h

@@ -0,0 +1,27 @@
+#pragma once
+
+#include <stdint.h>
+
+union GateDescriptor
+{
+	struct
+	{
+		uint16_t	offset_lo;
+		uint16_t	selector;
+		uint8_t		reserved;
+		uint8_t		type		: 4;
+		uint8_t		zero		: 1;
+		uint8_t		dpl			: 2;
+		uint8_t		present		: 1;
+		uint16_t	offset_hi;
+	};
+
+	struct
+	{
+		uint32_t low;
+		uint32_t high;
+	};
+	
+} __attribute__((packed));
+
+void idt_initialize();