Kernel: Move ACPI to its own file

kernel/include/kernel/ACPI.h

@@ -0,0 +1,43 @@
+#pragma once
+
+#include <BAN/Errors.h>
+
+namespace Kernel
+{
+
+	class ACPI
+	{
+	public:
+		struct SDTHeader
+		{
+			uint8_t signature[4];
+			uint32_t length;
+			uint8_t revision;
+			uint8_t checksum;
+			uint8_t oemid[6];
+			uint64_t oem_table_id;
+			uint32_t oem_revision;
+			uint32_t creator_id;
+			uint32_t creator_revision;
+		} __attribute__((packed));
+
+	public:
+		static BAN::ErrorOr<void> initialize();
+		static ACPI& get();
+
+		BAN::ErrorOr<const SDTHeader*> get_header(const char[4]);
+		void unmap_header(const SDTHeader*);
+
+	private:
+		ACPI() = default;
+		BAN::ErrorOr<void> initialize_impl();
+
+		const SDTHeader* get_header_from_index(size_t);
+
+	private:
+		uintptr_t m_header_table = 0;
+		uint32_t m_entry_size = 0;
+		uint32_t m_entry_count = 0;
+	};
+
+}