#!/usr/bin/env bash

# Copyright 2024 Gentoo Authors
# This script is installed by sys-kernel/linux-firmware, it is executed by
# the traditional installkernel, NOT by systemd's kernel-install. I.e. this
# plugin is run when the systemd USE flag is disabled or
# SYSTEMD_KERNEL_INSTALL=0 is set in the environment.

# familiar helpers, we intentionally don't use Gentoo functions.sh
die() {
	echo -e " ${NOCOLOR-\e[1;31m*\e[0m }${*}" >&2
	exit 1
}

einfo() {
	echo -e " ${NOCOLOR-\e[1;32m*\e[0m }${*}" >&2
}

main() {
	# re-define for subst to work
	[[ -n ${NOCOLOR+yes} ]] && NOCOLOR=

	if [[ ${INSTALLKERNEL_INITRD_GENERATOR} == dracut ]]; then
		# Dracut bundles microcode in its initramfs images
		echo "initrd_generator=${INSTALLKERNEL_INITRD_GENERATOR} bundles CPU microcode, nothing to do here."
		exit 0
	fi

	# do nothing if somehow make-amd-ucode-img is not installed
	[[ -x $(command -v make-amd-ucode-img) ]] || die "make-amd-ucode-img command not available"

	[[ ${EUID} -eq 0 ]] || die "Please run this script as root"

	einfo "Generating AMD CPU Microcode early initramfs image..."
	make-amd-ucode-img /boot/amd-uc.img /lib/firmware/amd-ucode ||
		die "make-amd-ucode-img failed"
}

main