#!/bin/sh
# Based on ar71xx 10-ath9k-eeprom

[ -e /lib/firmware/$FIRMWARE ] && exit 0

. /lib/functions.sh
. /lib/functions/system.sh
. /lib/upgrade/nand.sh

# xor multiple hex values of the same length
xor() {
	local val
	local ret="0x$1"
	local retlen=${#1}

	shift
	while [ -n "$1" ]; do
		val="0x$1"
		ret=$((ret ^ val))
		shift
	done

	printf "%0${retlen}x" "$ret"
}

ath9k_eeprom_die() {
	echo "ath9k eeprom: $*"
	exit 1
}

ath9k_eeprom_extract_raw() {
	local source=$1
	local offset=$2
	local swap=$3
	local size=4096
	local bs=1
	local conv=

	if [ $swap -gt 0 ]; then
		bs=2
		conv="conv=swab"
		size=$((size / bs))
		offset=$((offset / bs))
	fi

	dd if=$source of=/lib/firmware/$FIRMWARE bs=$bs skip=$offset count=$size $conv 2>/dev/null || \
			ath9k_eeprom_die "failed to extract from $mtd"
}

ath9k_eeprom_extract() {
	local part=$1
	local offset=$2
	local swap=$3
	local mtd

	mtd=$(find_mtd_chardev $part)
	[ -n "$mtd" ] || \
		ath9k_eeprom_die "no mtd device found for partition $part"

	ath9k_eeprom_extract_raw $mtd $offset $swap
}

ath9k_ubi_eeprom_extract() {
	local part=$1
	local offset=$2
	local swap=$3
	local ubidev=$(nand_find_ubi $CI_UBIPART)
	local ubi

	ubi=$(nand_find_volume $ubidev $part)
	[ -n "$ubi" ] || \
		ath9k_eeprom_die "no UBI volume found for $part"

	ath9k_eeprom_extract_raw /dev/$ubi $offset $swap
}

ath9k_patch_fw_mac_crc() {
	local mac=$1
	local mac_offset=$2
	local chksum_offset=$((mac_offset - 10))

	ath9k_patch_fw_mac "${mac}" "${mac_offset}" "${chksum_offset}"
}

ath9k_patch_fw_mac() {
	local mac=$1
	local mac_offset=$2
	local chksum_offset=$3
	local xor_mac
	local xor_fw_mac
	local xor_fw_chksum

	[ -z "$mac" -o -z "$mac_offset" ] && return

	[ -n "$chksum_offset" ] && {
		xor_mac=${mac//:/}
		xor_mac="${xor_mac:0:4} ${xor_mac:4:4} ${xor_mac:8:4}"

		xor_fw_mac=$(hexdump -v -n 6 -s $mac_offset -e '/1 "%02x"' /lib/firmware/$FIRMWARE)
		xor_fw_mac="${xor_fw_mac:0:4} ${xor_fw_mac:4:4} ${xor_fw_mac:8:4}"

		xor_fw_chksum=$(hexdump -v -n 2 -s $chksum_offset -e '/1 "%02x"' /lib/firmware/$FIRMWARE)
		xor_fw_chksum=$(xor $xor_fw_chksum $xor_fw_mac $xor_mac)

		printf "%b" "\x${xor_fw_chksum:0:2}\x${xor_fw_chksum:2:2}" | \
			dd of=/lib/firmware/$FIRMWARE conv=notrunc bs=1 seek=$chksum_offset count=2
	}

	macaddr_2bin $mac | dd of=/lib/firmware/$FIRMWARE conv=notrunc bs=1 seek=$mac_offset count=6
}

case "$FIRMWARE" in
	"ath9k-eeprom-pci-0000:00:0e.0.bin" | \
	"ath9k-eeprom-pci-0000:01:00.0.bin" | \
	"ath9k-eeprom-pci-0000:02:00.0.bin")
		board=$(board_name)

		case "$board" in
			arcadyan,arv7518pw)
				ath9k_eeprom_extract "boardconfig" 1024 1
				;;
			arcadyan,arv8539pw22)
				ath9k_eeprom_extract "art" 1024 1
				;;
			bt,homehub-v2b)
				ath9k_eeprom_extract "art" 0 1
				ath9k_patch_fw_mac_crc "00:00:00:00:00:00" 524
				;;
			bt,homehub-v3a)
				ath9k_eeprom_extract "art-copy" 0 1
				ath9k_patch_fw_mac_crc $(macaddr_add $(mtd_get_mac_ascii uboot_env ethaddr) +2) 268
				;;
			bt,homehub-v5a)
				ath9k_ubi_eeprom_extract "caldata" 4096 0
				ath9k_patch_fw_mac_crc $(macaddr_add $(mtd_get_mac_binary_ubi caldata 4364) +2) 268
				;;
			netgear,dgn3500|netgear,dgn3500b)
				ath9k_eeprom_extract "calibration" 61440 0
				ath9k_patch_fw_mac_crc $(macaddr_add $(mtd_get_mac_ascii uboot-env ethaddr) +2) 524
				;;
			avm,fritz3370|avm,fritz7320|avm,fritz7360sl)
				ath9k_eeprom_extract "urlader" 2437 0
				;;
			tplink,tdw8970|tplink,tdw8980)
				ath9k_eeprom_extract "boardconfig" 135168 0
				;;
			*)
				ath9k_eeprom_die "board $board is not supported yet"
				;;
		esac
		;;
esac