You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: acpi.rs
    path of file: ./repos/kernel/src/arch/x86_64/kernel
    
    the code of the file until where you have to start completion: use core::convert::Infallible;
use core::{mem, ptr, slice, str};

use align_address::Align;
use hermit_sync::OnceCell;
use x86::io::*;
use x86_64::structures::paging::PhysFrame;

use crate::arch::x86_64::kernel::processor;
use crate::arch::x86_64::mm::paging::{
	BasePageSize, PageSize, PageTableEntryFlags, PageTableEntryFlagsExt,
};
use crate::arch::x86_64::mm::{paging, virtualmem, PhysAddr, VirtAddr};

/// Memory at this physical address is supposed to contain a pointer to the Extended BIOS Data Area (EBDA).
const EBDA_PTR_LOCATION: PhysAddr = PhysAddr(0x0000_040E);
/// Minimum physical address where a valid EBDA must be located.
const EBDA_MINIMUM_ADDRESS: PhysAddr = PhysAddr(0x400);
/// The size of the EBDA window that is searched for an ACPI RSDP.
const EBDA_WINDOW_SIZE: usize = 1024;
/// The lower bound of the other address range, where the ACPI RSDP could be located.
const RSDP_SEARCH_ADDRESS_LOW: PhysAddr = PhysAddr(0xE_0000);
/// The upper bound of the other address range, where the ACPI RSDP could be located.
const RSDP_SEARCH_ADDRESS_HIGH: PhysAddr = PhysAddr(0xF_FFFF);
/// Length in bytes of the structure, over which the basic (ACPI 1.0) checksum is calculated.
const RSDP_CHECKSUM_LENGTH: usize = 20;
/// Length in byte sof the structure, over which the extended (ACPI 2.0+) chec
    
pub fn init() {
	// Detect the RSDP and get a pointer to either the XSDT (64-bit) or RSDT (32-bit), whichever is available.
	// Both are called RSDT in the following.
	let rsdp = detect_acpi().expect("Hermit requires an ACPI-compliant system");
	let rsdt_physical_address = if rsdp.revision >= 2 {
		PhysAddr(rsdp.xsdt_physical_address)
	} else {
		PhysAddr(rsdp.rsdt_physical_address.into())
	};

	// Map the RSDT.
	let rsdt = AcpiTable::map(rsdt_physical_address);

	// The RSDT contains pointers to all available ACPI tables.
	// Iterate through them.
	let mut current_address = rsdt.table_start_address();
	while current_address < rsdt.table_end_address() {
		// Depending on the RSDP revision, either an XSDT or an RSDT has been chosen above.
		// The XSDT contains 64-bit pointers whereas the RSDT has 32-bit pointers.
		let table_physical_address = if rsdp.revision >= 2 {
			let address = PhysAddr(unsafe {
				ptr::read_unaligned(ptr::from_exposed_addr::<u64>(current_address))
			});
			current_address += mem::size_of::<u64>();
			address
		} else {
			let address = PhysAddr(
				(unsafe { ptr::read_unaligned(ptr::from_exposed_addr::<u32>(current_address)) })
					.into(),
			);
			current_address += mem::size_of::<u32>();
			address
		};

		let table = AcpiTable::map(table_physical_address);
		debug!("Found ACPI table: {}", table.header.signature());

		if table.header.signature() == "APIC" {
			// The "Multiple APIC Description Table" (MADT) aka "APIC Table" (APIC)
			// Check and save the entire APIC table for the get_apic_table() call.
			assert!(
				verify_checksum(table.header_start_address(), table.header.length as usize).is_ok(),
				"MADT at {table_physical_address:p} has invalid checksum"
			);
			MADT.set(table).unwrap();
		} else if table.header.signature() == "FACP" {
			// The "Fixed ACPI Description Table" (FADT) aka "Fixed ACPI Control Pointer" (FACP)
			// Check and parse this table for the poweroff() call.
			assert!(
				verify_checksum(table.header_start_address(), table.header.length as usize).is_ok(),
				"FADT at {table_physical_address:p} has invalid checksum"
			);
			parse_fadt(table);
		} else if table.header.signature() == "SSDT" {
			assert!(
				verify_checksum(table.header_start_address(), table.header.length as usize).is_ok(),
				"SSDT at {table_physical_address:p} has invalid checksum"
			);
			parse_ssdt(table);
		}
	}
}