ipq806x: add ath10k calibration data MAC addresses patching

Ben Greear reported in his patch:
|Subject: netgear r7800: Fix mac address of radios.
|
|Reloading the driver causes the phyX to change, and that
|caused the MAC address to change.

This is because all ODM/OEMs except QCA bothered to write
the correct MAC address for the ath10k wifi into the
calibration data.

This patch copies over the MAC patching helper functions from ipq40xx's
target/linux/ipq40xx/base-files/etc/hotplug.d/firmware/11-ath10k-caldata
file and converts all the devices to patch the correct MACs into the
extracted calibration data before it gets sent to the driver, which sets
up the device with the correct MAC address. It also removes the entries
in the 10_fix_wifi_mac file as they have served their purpose for good.

Please note the C2600: There is conflicting information on what
the offset for the second wifi is supposed to be. This patch uses
what was specified in 10_fix_wifi_mac.

According to Ben Greear this method is save to use with the
stock firmware too. As he explained that the stock firmware
messes up rx-bssid mask calculation when the MAC is changed
after the first vif is created.

Reported-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>

target/linux/ipq806x/base-files/etc/hotplug.d/firmware/11-ath10k-caldata

@@ -1,5 +1,21 @@
 #!/bin/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"
+}
+
 ath10kcal_die() {
 	echo "ath10cal: " "$*"
 	exit 1
@@ -28,12 +44,29 @@ ath10kcal_extract() {
 		ath10kcal_die "failed to extract calibration data from $mtd"
 }
 
-ath10kcal_patch_mac() {
+ath10kcal_patch_mac_crc() {
 	local mac=$1
+	local mac_offset=6
+	local chksum_offset=2
+	local xor_mac
+	local xor_fw_mac
+	local xor_fw_chksum
 
 	[ -z "$mac" ] && return
 
+	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}"
+
 	macaddr_2bin $mac | dd of=/lib/firmware/$FIRMWARE conv=notrunc bs=1 seek=6 count=6
+
+	xor_mac=${mac//:/}
+	xor_mac="${xor_mac:0:4} ${xor_mac:4:4} ${xor_mac:8:4}"
+
+	xor_fw_chksum=$(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
 }
 
 [ -e /lib/firmware/$FIRMWARE ] && exit 0
@@ -43,53 +76,64 @@ ath10kcal_patch_mac() {
 
 board=$(board_name)
 
-
 case "$FIRMWARE" in
 "ath10k/pre-cal-pci-0000:01:00.0.bin")
 	case $board in
 	linksys,ea8500)
-		hw_mac_addr=$(mtd_get_mac_ascii devinfo hw_mac_addr)
 		ath10kcal_extract "art" 4096 12064
+		ath10kcal_patch_mac_crc $(macaddr_add $(mtd_get_mac_ascii devinfo hw_mac_addr) +1)
+		;;
+	nec,wg2600hp)
+		ath10kcal_extract "ART" 4096 12064
+		ath10kcal_patch_mac_crc $(macaddr_add $(mtd_get_mac_binary PRODUCTDATA 12) +1)
 		;;
 	netgear,d7800 |\
 	netgear,r7500v2 |\
 	netgear,r7800)
 		ath10kcal_extract "art" 4096 12064
+		ath10kcal_patch_mac_crc $(macaddr_add $(mtd_get_mac_binary art 6) +1)
 		;;
 	tplink,c2600)
 		ath10kcal_extract "radio" 4096 12064
-# 		ath10kcal_patch_mac $(macaddr_add $(mtd_get_mac_binary default-mac 8) -1)
+		ath10kcal_patch_mac_crc $(macaddr_add $(mtd_get_mac_binary default-mac 8) -1)
 		;;
-	nec,wg2600hp |\
 	tplink,vr2600v)
 		ath10kcal_extract "ART" 4096 12064
+		ath10kcal_patch_mac_crc $(macaddr_add $(mtd_get_mac_binary default-mac 0) -1)
 		;;
 	zyxel,nbg6817)
 		ath10kcal_extract "0:ART" 4096 12064
+		ath10kcal_patch_mac_crc $(macaddr_add $(mtd_get_mac_ascii 0:APPSBLENV ethaddr) +1)
 		;;
 	esac
 	;;
 "ath10k/pre-cal-pci-0001:01:00.0.bin")
 	case $board in
 	linksys,ea8500)
-		hw_mac_addr=$(mtd_get_mac_ascii devinfo hw_mac_addr)
 		ath10kcal_extract "art" 20480 12064
+		ath10kcal_patch_mac_crc $(macaddr_add $(mtd_get_mac_ascii devinfo hw_mac_addr) +2)
+		;;
+	nec,wg2600hp)
+		ath10kcal_extract "ART" 20480 12064
+		ath10kcal_patch_mac_crc $(mtd_get_mac_binary PRODUCTDATA 12)
 		;;
 	netgear,d7800 |\
 	netgear,r7500v2 |\
 	netgear,r7800)
 		ath10kcal_extract "art" 20480 12064
+		ath10kcal_patch_mac_crc $(macaddr_add $(mtd_get_mac_binary art 6) +2)
 		;;
 	tplink,c2600)
 		ath10kcal_extract "radio" 20480 12064
-# 		ath10kcal_patch_mac $(macaddr_add $(mtd_get_mac_binary default-mac 8) -2)
+		ath10kcal_patch_mac_crc $(mtd_get_mac_binary default-mac 8)
 		;;
-	nec,wg2600hp |\
 	tplink,vr2600v)
 		ath10kcal_extract "ART" 20480 12064
+		ath10kcal_patch_mac_crc $(mtd_get_mac_binary default-mac 0)
 		;;
 	zyxel,nbg6817)
 		ath10kcal_extract "0:ART" 20480 12064
+		ath10kcal_patch_mac_crc $(mtd_get_mac_ascii 0:APPSBLENV ethaddr)
 		;;
 	esac
 	;;

target/linux/ipq806x/base-files/etc/hotplug.d/ieee80211/10_fix_wifi_mac

@@ -9,33 +9,6 @@ PHYNBR=${DEVPATH##*/phy}
 . /lib/functions.sh
 . /lib/functions/system.sh
 
-board=$(board_name)
-
-case "$board" in
-	linksys,ea8500)
-		echo $(macaddr_add $(mtd_get_mac_ascii devinfo hw_mac_addr) $(($PHYNBR + 1)) ) > /sys${DEVPATH}/macaddress
-		;;
-	nec,wg2600hp)
-		echo $(macaddr_add $(mtd_get_mac_binary PRODUCTDATA 12) $((1 - $PHYNBR)) ) > /sys${DEVPATH}/macaddress
-		;;
-	netgear,d7800 |\
-	netgear,r7500v2 |\
-	netgear,r7800)
-		echo $(macaddr_add $(mtd_get_mac_binary art 6)  $(($PHYNBR + 1)) ) > /sys${DEVPATH}/macaddress
-		;;
-	tplink,c2600)
-		echo $(macaddr_add $(mtd_get_mac_binary default-mac 8)  $(($PHYNBR - 1)) ) > /sys${DEVPATH}/macaddress
-		;;
-	tplink,vr2600v)
-		echo $(macaddr_add $(mtd_get_mac_binary default-mac 0)  $(($PHYNBR - 1)) ) > /sys${DEVPATH}/macaddress
-		;;
-	zyxel,nbg6817)
-		echo $(macaddr_add $(mtd_get_mac_ascii 0:APPSBLENV ethaddr) $((1 - $PHYNBR)) ) > /sys${DEVPATH}/macaddress
-		;;
-	*)
-		;;
-esac
-
 OPATH=${DEVPATH##/devices/platform/}
 OPATH=${OPATH%%/ieee*}