#!/bin/ksh

# This file and its contents are supplied under the terms of the
# Common Development and Distribution License ("CDDL"), version 1.0.
# You may only use this file in accordance with the terms of version
# 1.0 of the CDDL.
#
# A full copy of the text of the CDDL should have accompanied this
# source. A copy of the CDDL is also available via the Internet at
# http://www.illumos.org/license/CDDL.

# Copyright 2022 OmniOS Community Edition (OmniOSce) Association.
# Copyright 2023 Oxide Computer Company

# A simple update script that checks out the upstream AMD firmware
# repository, extracts the microcode into separate files within the amd/
# directory, generates the required combined equivalence table and updates
# the pkg(7) manifest.

UPSTREAM=git://git.kernel.org
UPSTREAM_PATH=/pub/scm/linux/kernel/git/firmware/linux-firmware.git

# These are the GPG keys that AMD use to sign their CPU microcode updates
# The first key is the current one and the second is one they have used for
# older CPU families.
GPGSERVER=keys.gnupg.net
typeset -a GPGKEYS=(
	0xFC7C6C505DAFCC14718357CAE4BE5339F328AE73
	0x916A770823A7B27AADE01565A5E8DBC98C0108B4
)

function errexit {
	echo "$@" >&2
	exit 1
}

FW=platform/i86pc/ucode/AuthenticAMD

export LC_ALL=C.UTF-8

set -e
set -o pipefail

mf=../../pkg/manifests/system-microcode-amd.p5m
[[ -f $mf ]] || errexit "Run from usr/src/data/ucode"

function find_cmd {
	typeset cmd="$1"
	typeset var=$(echo $cmd | tr '[:lower:]' '[:upper:]')
	typeset -n path="$var"
	path=$(whence -fp "$cmd")
	if (($? != 0)) || [ ! -x "$path" ]; then
		errexit "Cannot find executable '$cmd' in PATH"
	fi
}

# This script uses a few commands which are not part of illumos and are
# expected to be available in the path.
find_cmd git
find_cmd gpg
find_cmd pkgfmt
find_cmd stat
# Search for 'ucodeadm'. If you need to use an updated ucodeadm to handle this
# firmware update, as is occasionally necessary, ensure it occurs earlier in
# the path than /usr/sbin.
find_cmd ucodeadm

tmp=$(mktemp -d)
[[ -n "$tmp" && -d "$tmp" ]]
mkdir $tmp/out || errexit "Failed to create temporary directory"
trap 'rm -rf $tmp' EXIT

echo "** Adding AMD GPG signing keys to temporary keyring"
mkdir -m 0700 $tmp/gnupg
$GPG --homedir $tmp/gnupg --keyserver $GPGSERVER --receive-keys ${GPGKEYS[@]}

echo "** Cloning $UPSTREAM$UPSTREAM_PATH"
$GIT clone $UPSTREAM$UPSTREAM_PATH $tmp/ucode

ver=`$GIT -C $tmp/ucode log -n1 --format=%ad --date=format:%Y%m%d amd-ucode`
echo "** Updating to microcode version $ver"

echo "** Verifying microcode signatures"
for f in $tmp/ucode/amd-ucode/*.bin; do
	if [[ ! -f "$f.asc" ]]; then
		echo "Signature missing for ${f##*/}"
		exit 1
	fi
	$GPG --homedir $tmp/gnupg --trust-model=always --verify $f{.asc,}
done

# Now that everything is in place and verified, begin modifying the tree.

rm -f amd/*-*

cp $tmp/ucode/LICENSE.amd-ucode amd/THIRDPARTYLICENSE
echo AMD Processor Microcode Data Files > amd/THIRDPARTYLICENSE.descrip

for f in $tmp/ucode/amd-ucode/*.bin; do
	bf=${f##*/}
	bf=${bf#microcode_}
	bf=${bf%.bin}
	[[ $bf = amd* ]] || errexit "$f does not look like a firmware file"
	echo "Converting $bf"
	mkdir $tmp/out/$bf
	cp $f $tmp/amd-fw
	$UCODEADM -l $tmp/amd-fw
	$UCODEADM -i -R $tmp/out/$bf $tmp/amd-fw
	rm -f $tmp/amd-fw
done

# Copy the firmware files into place
cp $tmp/out/*/*-?? amd/

# Combine the equivalence tables from the different updates into one
# Each equivalence-table file is a sequence of 16-byte records with a
# 16-byte terminator which is all zeros. To merge, we just concatenate
# the non-terminator records and then add 16 bytes from /dev/zero.
{
	for f in $tmp/out/*/equivalence-table; do
		size=$($STAT -c %s $f)
		((size -= 16))
		dd if=$f bs=1 count=$size status=none
	done
	# Add terminator
	dd if=/dev/zero bs=1 count=16 status=none
} > amd/equivalence-table

$PKGFMT -u $mf
mv $mf $mf.tmp
egrep -v "file path=$FW" $mf.tmp > $mf
rm -f $mf.tmp

for f in amd/*; do
	bf=${f##*/}
	[[ $bf = THIRDPARTYLICENSE* ]] && continue
	[[ $bf = Makefile* ]] && continue
	echo "file path=$FW/$bf group=sys mode=0444 reboot-needed=true" >> $mf
done

sed -i "/pkg.fmri.*microcode\/amd@/s/@[0-9]*/@$ver/" $mf

$PKGFMT -fv2 $mf