/etc/initcpio/install/custom_acpi. Add the patched acpi tables to /etc/custom_acpi, for example: /etc/custom_acpi/DSDT

custom_acpi.sh

#!/usr/bin/env bash

__basename() {
	local tmp
	tmp=${1%"${1##*[!/]}"}
	tmp=${tmp##*/}
	tmp=${tmp%"${2/"$tmp"}"}
	printf '%s\n' "${tmp:-/}"
}

tables_directory="/etc/custom_acpi"

build() {
	find "${tables_directory}" -type f -print0 | while IFS= read -r -d $'\0' table; do
		local table_name=$(__basename "${table}")
		add_file "${table}" "/kernel/firmware/acpi/${table_name,,}.aml"
	done
}

help() {
	echo "This hook adds acpi table patches from ${tables_directory}."
}