ar71xx: add support for Fritz!Box 4020

This commit adds support for the AVM Fritz!Box 4020 WiFi-router.

SoC:   Qualcomm Atheros QCA9561 (Dragonfly) 750MHz
RAM:   Winbond W971GG6KB-25
FLASH: Macronix MX25L12835F
WiFi:  QCA9561 b/g/n 3x3 450Mbit/s
USB:   1x USB 2.0
IN:    WPS button, WiFi button
OUT:   Power LED green, Internet LED green, WLAN LED green,
       LAN LED green, INFO LED green, INFO LED red
UART:  Header Next to Black metal shield
       Pinout is 3.3V - RX - TX - GND (Square Pad is 3.3V)
       The Serial setting is 115200-8-N-1.

Tested and working:
 - Ethernet (LAN + WAN)
 - WiFi (correct MAC)
 - Installation via EVA bootloader
 - OpenWRT sysupgrade
 - Buttons
 - LEDs

Not working:
 - USB port

Installation via EVA:
In the first seconds after Power is connected, the bootloader will
listen for FTP connections on 169.254.157.1 (Might also be 192.168.178.1). Firmware can be uploaded
like following:

  ftp> quote USER adam2
  ftp> quote PASS adam2
  ftp> binary
  ftp> debug
  ftp> passive
  ftp> quote MEDIA FLSH
  ftp> put openwrt-sysupgrade.bin mtd1

Note that this procedure might take up to two minutes. After transfer is
complete you need to powercycle the device to boot OpenWRT.

Signed-off-by: David Bauer <mail@david-bauer.net>

14 files changed, 300 insertions, 6 deletions

diff --git a/target/linux/ar71xx/base-files/etc/board.d/01_leds b/target/linux/ar71xx/base-files/etc/board.d/01_leds
index 906c4b7..52f1ac3 100755
--- a/target/linux/ar71xx/base-files/etc/board.d/01_leds
+++ b/target/linux/ar71xx/base-files/etc/board.d/01_leds
@@ -372,6 +372,12 @@ epg5000)
 	ucidef_set_led_wlan "wlan2g" "WLAN 2.4 GHz" "$board:blue:wlan-2g" "phy1tpt"
 	ucidef_set_led_wlan "wlan5g" "WLAN 5 GHz" "$board:blue:wlan-5g" "phy0tpt"
 	;;
+fritz4020)
+	ucidef_set_led_default "power" "Power" "$board:green:power" "1"
+	ucidef_set_led_netdev "lan" "LAN" "$board:green:lan" "eth1"
+	ucidef_set_led_netdev "wan" "WAN" "$board:green:wan" "eth0"
+	ucidef_set_led_wlan "wlan" "WLAN" "$board:green:wlan" "phy0tpt"
+	;;
 gl-ar300m)
 	ucidef_set_led_wlan "wlan" "WLAN" "$board:red:wlan" "phy0tpt"
 	;;
diff --git a/target/linux/ar71xx/base-files/etc/board.d/02_network b/target/linux/ar71xx/base-files/etc/board.d/02_network
index cbbcf53..5898261 100755
--- a/target/linux/ar71xx/base-files/etc/board.d/02_network
+++ b/target/linux/ar71xx/base-files/etc/board.d/02_network
@@ -243,6 +243,7 @@ ar71xx_setup_interfaces()
 		;;
 	archer-c58-v1|\
 	archer-c59-v1|\
+	fritz4020|\
 	rb-450g)
 		ucidef_set_interfaces_lan_wan "eth1.1" "eth0"
 		ucidef_add_switch "switch0" \
diff --git a/target/linux/ar71xx/base-files/etc/hotplug.d/firmware/10-ath9k-eeprom b/target/linux/ar71xx/base-files/etc/hotplug.d/firmware/10-ath9k-eeprom
index 41ab43f..6eb9464 100644
--- a/target/linux/ar71xx/base-files/etc/hotplug.d/firmware/10-ath9k-eeprom
+++ b/target/linux/ar71xx/base-files/etc/hotplug.d/firmware/10-ath9k-eeprom
@@ -75,6 +75,9 @@ case "$FIRMWARE" in
 		ath9k_eeprom_extract "art" 4096 2048
 		ath9k_patch_firmware_mac $(macaddr_add $(mtd_get_mac_binary art 0) +1)
 		;;
+	fritz4020)
+		ath9k_eeprom_extract_reverse "urlader" 5441 1088
+		;;
 	mr18)
 		. /lib/upgrade/nand.sh
 
diff --git a/target/linux/ar71xx/base-files/lib/ar71xx.sh b/target/linux/ar71xx/base-files/lib/ar71xx.sh
index 95314a2..42bd80d 100755
--- a/target/linux/ar71xx/base-files/lib/ar71xx.sh
+++ b/target/linux/ar71xx/base-files/lib/ar71xx.sh
@@ -709,6 +709,9 @@ ar71xx_board_detect() {
 	*"eTactica EG-200")
 		name="rme-eg200"
 		;;
+	*"FRITZ!Box 4020")
+		name="fritz4020"
+		;;
 	*"FRITZ!WLAN Repeater 300E")
 		name="fritz300e"
 		;;
diff --git a/target/linux/ar71xx/base-files/lib/upgrade/platform.sh b/target/linux/ar71xx/base-files/lib/upgrade/platform.sh
index 702d97a..284582f 100755
--- a/target/linux/ar71xx/base-files/lib/upgrade/platform.sh
+++ b/target/linux/ar71xx/base-files/lib/upgrade/platform.sh
@@ -686,6 +686,7 @@ platform_check_image() {
 		;;
 	# these boards use metadata images
 	fritz300e|\
+	fritz4020|\
 	rb-750-r2|\
 	rb-750p-pbr2|\
 	rb-750up-r2|\
diff --git a/target/linux/ar71xx/config-4.9 b/target/linux/ar71xx/config-4.9
index 5cea1b7..35efd17 100644
--- a/target/linux/ar71xx/config-4.9
+++ b/target/linux/ar71xx/config-4.9
@@ -115,6 +115,7 @@ CONFIG_ATH79=y
 # CONFIG_ATH79_MACH_EW_DORIN is not set
 # CONFIG_ATH79_MACH_F9K1115V2 is not set
 # CONFIG_ATH79_MACH_FRITZ300E is not set
+# CONFIG_ATH79_MACH_FRITZ4020 is not set
 # CONFIG_ATH79_MACH_GL_AR150 is not set
 # CONFIG_ATH79_MACH_GL_AR300 is not set
 # CONFIG_ATH79_MACH_GL_AR300M is not set
diff --git a/target/linux/ar71xx/files/arch/mips/ath79/Kconfig.openwrt b/target/linux/ar71xx/files/arch/mips/ath79/Kconfig.openwrt
index 4a032f6..40d33b5 100644
--- a/target/linux/ar71xx/files/arch/mips/ath79/Kconfig.openwrt
+++ b/target/linux/ar71xx/files/arch/mips/ath79/Kconfig.openwrt
@@ -2347,3 +2347,12 @@ config ATH79_MACH_FRITZ300E
 	select ATH79_DEV_GPIO_BUTTONS
 	select ATH79_DEV_LEDS_GPIO
 	select ATH79_DEV_M25P80
+
+config ATH79_MACH_FRITZ4020
+	bool "AVM FRITZ!Box 4020 support"
+	select SOC_QCA956X
+	select ATH79_DEV_ETH
+	select ATH79_DEV_GPIO_BUTTONS
+	select ATH79_DEV_LEDS_GPIO
+	select ATH79_DEV_USB
+	select ATH79_DEV_M25P80
diff --git a/target/linux/ar71xx/files/arch/mips/ath79/Makefile b/target/linux/ar71xx/files/arch/mips/ath79/Makefile
index e606e2c..2124ab7 100644
--- a/target/linux/ar71xx/files/arch/mips/ath79/Makefile
+++ b/target/linux/ar71xx/files/arch/mips/ath79/Makefile
@@ -125,6 +125,7 @@ obj-$(CONFIG_ATH79_MACH_EW_BALIN)		+= mach-ew-balin.o
 obj-$(CONFIG_ATH79_MACH_EW_DORIN)		+= mach-ew-dorin.o
 obj-$(CONFIG_ATH79_MACH_F9K1115V2)		+= mach-f9k1115v2.o
 obj-$(CONFIG_ATH79_MACH_FRITZ300E)		+= mach-fritz300e.o
+obj-$(CONFIG_ATH79_MACH_FRITZ4020)		+= mach-fritz4020.o
 obj-$(CONFIG_ATH79_MACH_GL_AR150)		+= mach-gl-ar150.o
 obj-$(CONFIG_ATH79_MACH_GL_AR300)		+= mach-gl-ar300.o
 obj-$(CONFIG_ATH79_MACH_GL_AR300M)		+= mach-gl-ar300m.o
diff --git a/target/linux/ar71xx/files/arch/mips/ath79/dev-eth.c b/target/linux/ar71xx/files/arch/mips/ath79/dev-eth.c
index 9e72c41..b46bab7 100644
--- a/target/linux/ar71xx/files/arch/mips/ath79/dev-eth.c
+++ b/target/linux/ar71xx/files/arch/mips/ath79/dev-eth.c
@@ -1175,6 +1175,15 @@ void __init ath79_parse_ascii_mac(char *mac_str, u8 *mac)
 	}
 }
 
+void __init ath79_extract_mac_reverse(u8 *ptr, u8 *out)
+{
+	int i;
+
+	for (i = 0; i < ETH_ALEN; i++) {
+		out[i] = ptr[ETH_ALEN-i-1];
+	}
+}
+
 static void __init ath79_set_mac_base_ascii(char *str)
 {
 	u8 mac[ETH_ALEN];
diff --git a/target/linux/ar71xx/files/arch/mips/ath79/dev-eth.h b/target/linux/ar71xx/files/arch/mips/ath79/dev-eth.h
index fb9e4f6..4d78260 100644
--- a/target/linux/ar71xx/files/arch/mips/ath79/dev-eth.h
+++ b/target/linux/ar71xx/files/arch/mips/ath79/dev-eth.h
@@ -18,6 +18,7 @@ struct platform_device;
 
 extern unsigned char ath79_mac_base[] __initdata;
 void ath79_parse_ascii_mac(char *mac_str, u8 *mac);
+void ath79_extract_mac_reverse(u8 *ptr, u8 *out);
 void ath79_init_mac(unsigned char *dst, const unsigned char *src,
 		    int offset);
 void ath79_init_local_mac(unsigned char *dst, const unsigned char *src);
diff --git a/target/linux/ar71xx/files/arch/mips/ath79/mach-fritz4020.c b/target/linux/ar71xx/files/arch/mips/ath79/mach-fritz4020.c
new file mode 100644
index 0000000..ed7f9a8
--- /dev/null
+++ b/target/linux/ar71xx/files/arch/mips/ath79/mach-fritz4020.c
@@ -0,0 +1,242 @@
+/*
+ *  AVM FRITZ!Box 4020 board support
+ *
+ *  Copyright (C) 2018 David Bauer <mail@david-bauer.net>
+ *
+ *  This program is free software; you can redistribute it and/or modify it
+ *  under the terms of the GNU General Public License version 2 as published
+ *  by the Free Software Foundation.
+ */
+
+#include <linux/init.h>
+#include <linux/ath9k_platform.h>
+#include <linux/etherdevice.h>
+#include <linux/gpio.h>
+#include <linux/platform_device.h>
+
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/partitions.h>
+#include <linux/platform_data/mdio-gpio.h>
+#include <linux/spi/spi_gpio.h>
+#include <linux/spi/74x164.h>
+
+#include <asm/mach-ath79/ath79.h>
+#include <asm/mach-ath79/ar71xx_regs.h>
+
+#include "common.h"
+#include "dev-eth.h"
+#include "dev-gpio-buttons.h"
+#include "dev-leds-gpio.h"
+#include "dev-m25p80.h"
+#include "dev-spi.h"
+#include "dev-usb.h"
+#include "dev-wmac.h"
+#include "machtypes.h"
+
+
+#define FRITZ4020_GPIO_SHIFT_SER			19   /* DS,   Data Serial Input */
+#define FRITZ4020_GPIO_SHIFT_SRCLK			20 /* SHCP, Shift Reg Clock Input */
+
+#define FRITZ4020_SSR_BIT_0				0
+#define FRITZ4020_SSR_BIT_1				1
+#define FRITZ4020_SSR_BIT_2				2
+#define FRITZ4020_SSR_BIT_3				3
+#define FRITZ4020_SSR_BIT_4				4
+#define FRITZ4020_SSR_BIT_5				5
+#define FRITZ4020_SSR_BIT_6				6
+#define FRITZ4020_SSR_BIT_7				7
+
+#define FRITZ4020_74HC_GPIO_BASE			32
+#define FRITZ4020_74HC_GPIO_LED_LAN			(FRITZ4020_74HC_GPIO_BASE + 0)
+#define FRITZ4020_74HC_GPIO_LED_INFO_RED		(FRITZ4020_74HC_GPIO_BASE + 1)
+#define FRITZ4020_74HC_GPIO_LED_POWER			(FRITZ4020_74HC_GPIO_BASE + 2)
+#define FRITZ4020_74HC_GPIO_LED_WLAN			(FRITZ4020_74HC_GPIO_BASE + 3)
+#define FRITZ4020_74HC_GPIO_LED_WAN			(FRITZ4020_74HC_GPIO_BASE + 4)
+#define FRITZ4020_74HC_GPIO_USB_RST			(FRITZ4020_74HC_GPIO_BASE + 5)
+#define FRITZ4020_74HC_GPIO_LED_INFO			(FRITZ4020_74HC_GPIO_BASE + 6)
+
+
+#define FRITZ4020_GPIO_BTN_WPS				2
+#define FRITZ4020_GPIO_BTN_WLAN				21
+#define FRITZ4020_KEYS_POLL_INTERVAL			20 /* msecs */
+#define FRITZ4020_KEYS_DEBOUNCE_INTERVAL		(3 * FRITZ4020_KEYS_POLL_INTERVAL)
+
+#define FRTIZ4020_OFFSET_URLADER_WIFI_MAC_REVERSE	0x1979
+
+
+static struct spi_gpio_platform_data fritz4020_spi_data = {
+	.sck		= FRITZ4020_GPIO_SHIFT_SRCLK,
+	.miso		= SPI_GPIO_NO_MISO,
+	.mosi		= FRITZ4020_GPIO_SHIFT_SER,
+	.num_chipselect	= 1,
+};
+
+static u8 fritz4020_ssr_initdata[] = {
+	BIT(FRITZ4020_SSR_BIT_7) |
+	BIT(FRITZ4020_SSR_BIT_6) |
+	BIT(FRITZ4020_SSR_BIT_5) |
+	BIT(FRITZ4020_SSR_BIT_4) |
+	BIT(FRITZ4020_SSR_BIT_3) |
+	BIT(FRITZ4020_SSR_BIT_2) |
+	BIT(FRITZ4020_SSR_BIT_1)
+};
+
+static struct gen_74x164_chip_platform_data fritz4020_ssr_data = {
+	.base = FRITZ4020_74HC_GPIO_BASE,
+	.num_registers = ARRAY_SIZE(fritz4020_ssr_initdata),
+	.init_data = fritz4020_ssr_initdata,
+};
+
+static struct platform_device fritz4020_spi_device = {
+	.name		= "spi_gpio",
+	.id		= 1,
+	.dev = {
+		.platform_data = &fritz4020_spi_data,
+	},
+};
+
+static struct spi_board_info fritz4020_spi_info[] = {
+	{
+		.bus_num		= 1,
+		.chip_select		= 0,
+		.max_speed_hz		= 10000000,
+		.modalias		= "74x164",
+		.platform_data		= &fritz4020_ssr_data,
+		.controller_data	= (void *) 0x0,
+	},
+};
+
+static struct mtd_partition fritz4020_flash_partitions[] = {
+	{
+		.name		= "urlader",
+		.offset		= 0,
+		.size		= 0x0020000,
+		.mask_flags	= MTD_WRITEABLE,
+	}, {
+		.name		= "firmware",
+		.offset		= 0x0020000,
+		.size		= 0x0EE0000,
+	}, {
+		.name		= "tffs (1)",
+		.offset		= 0x0f00000,
+		.size		= 0x0080000,
+		.mask_flags	= MTD_WRITEABLE,
+	}, {
+		.name		= "tffs (2)",
+		.offset		= 0x0f80000,
+		.size		= 0x0080000,
+		.mask_flags	= MTD_WRITEABLE,
+	}
+};
+
+static struct flash_platform_data fritz4020_flash_data = {
+	.parts		= fritz4020_flash_partitions,
+	.nr_parts	= ARRAY_SIZE(fritz4020_flash_partitions),
+};
+
+static struct gpio_led fritz4020_leds_gpio[] __initdata = {
+	{
+		.name		= "fritz4020:green:lan",
+		.gpio		= FRITZ4020_74HC_GPIO_LED_LAN,
+		.active_low	= 1,
+	}, {
+		.name		= "fritz4020:green:info",
+		.gpio		= FRITZ4020_74HC_GPIO_LED_INFO,
+		.active_low	= 1,
+	}, {
+		.name		= "fritz4020:red:info",
+		.gpio		= FRITZ4020_74HC_GPIO_LED_INFO_RED,
+		.active_low	= 1,
+	}, {
+		.name		= "fritz4020:green:power",
+		.gpio		= FRITZ4020_74HC_GPIO_LED_POWER,
+		.active_low	= 1,
+	}, {
+		.name		= "fritz4020:green:wlan",
+		.gpio		= FRITZ4020_74HC_GPIO_LED_WLAN,
+		.active_low	= 1,
+	}, {
+		.name		= "fritz4020:green:wan",
+		.gpio		= FRITZ4020_74HC_GPIO_LED_WAN,
+		.active_low	= 1,
+	},
+};
+
+static struct gpio_keys_button fritz4020_gpio_keys[] __initdata = {
+	{
+		.desc			= "RFKILL button",
+		.type			= EV_KEY,
+		.code			= KEY_RFKILL,
+		.debounce_interval	= FRITZ4020_KEYS_DEBOUNCE_INTERVAL,
+		.gpio			= FRITZ4020_GPIO_BTN_WLAN,
+		.active_low		= 0,
+	},
+	{
+		.desc			= "WPS button",
+		.type			= EV_KEY,
+		.code			= KEY_WPS_BUTTON,
+		.debounce_interval	= FRITZ4020_KEYS_DEBOUNCE_INTERVAL,
+		.gpio			= FRITZ4020_GPIO_BTN_WPS,
+		.active_low		= 0,
+	},
+};
+
+static void __init fritz4020_setup(void) {
+	u8 *urlader = (u8 *) KSEG1ADDR(0x1f000000);
+	u8 wifi_mac[ETH_ALEN];
+
+	ath79_register_m25p80(&fritz4020_flash_data);
+
+	/* Initialize ethernet */
+	ath79_extract_mac_reverse(urlader + FRTIZ4020_OFFSET_URLADER_WIFI_MAC_REVERSE, wifi_mac);
+	ath79_setup_qca956x_eth_cfg(QCA956X_ETH_CFG_SW_PHY_SWAP |
+				    QCA956X_ETH_CFG_SW_PHY_ADDR_SWAP);
+
+	ath79_register_mdio(0, 0x0);
+	ath79_register_mdio(1, 0x0);
+	ath79_init_mac(ath79_eth0_data.mac_addr, wifi_mac, -1);
+	ath79_init_mac(ath79_eth1_data.mac_addr, wifi_mac, -2);
+
+	/* WAN port */
+	ath79_eth0_data.phy_if_mode = PHY_INTERFACE_MODE_MII;
+	ath79_eth0_data.speed = SPEED_100;
+	ath79_eth0_data.duplex = DUPLEX_FULL;
+	ath79_eth0_data.phy_mask = BIT(0);
+	ath79_register_eth(0);
+
+	/* LAN ports */
+	ath79_eth1_data.phy_if_mode = PHY_INTERFACE_MODE_GMII;
+	ath79_eth1_data.speed = SPEED_1000;
+	ath79_eth1_data.duplex = DUPLEX_FULL;
+	ath79_switch_data.phy_poll_mask |= BIT(0);
+	ath79_switch_data.phy4_mii_en = 1;
+	ath79_register_eth(1);
+
+	/* Initialize 2.4GHz WiFi */
+	ath79_register_wmac_simple();
+
+	/* Activate USB Power */
+	gpio_request_one(FRITZ4020_74HC_GPIO_USB_RST,
+			 GPIOF_OUT_INIT_HIGH | GPIOF_EXPORT_DIR_FIXED,
+			 "USB power");
+
+	/* Initialize USB port */
+	ath79_register_usb();
+
+	/* Register LED shift-register */
+	spi_register_board_info(fritz4020_spi_info,
+				ARRAY_SIZE(fritz4020_spi_info));
+	platform_device_register(&fritz4020_spi_device);
+
+	/* Register GPIO buttons */
+	ath79_register_gpio_keys_polled(-1, FRITZ4020_KEYS_POLL_INTERVAL,
+					ARRAY_SIZE(fritz4020_gpio_keys),
+					fritz4020_gpio_keys);
+
+	/* Register LEDs */
+	ath79_register_leds_gpio(-1, ARRAY_SIZE(fritz4020_leds_gpio),
+				 fritz4020_leds_gpio);
+}
+
+MIPS_MACHINE(ATH79_MACH_FRITZ4020, "FRITZ4020",
+	     "AVM FRITZ!Box 4020", fritz4020_setup);
diff --git a/target/linux/ar71xx/files/arch/mips/ath79/machtypes.h b/target/linux/ar71xx/files/arch/mips/ath79/machtypes.h
index b61ed7a..3d5bcfb 100644
--- a/target/linux/ar71xx/files/arch/mips/ath79/machtypes.h
+++ b/target/linux/ar71xx/files/arch/mips/ath79/machtypes.h
@@ -120,6 +120,7 @@ enum ath79_mach_type {
 	ATH79_MACH_EW_DORIN_ROUTER,		/* embedded wireless Dorin Router Platform */
 	ATH79_MACH_F9K1115V2,			/* Belkin AC1750DB */
 	ATH79_MACH_FRITZ300E,			/* AVM FRITZ!WLAN Repeater 300E */
+	ATH79_MACH_FRITZ4020,			/* AVM FRITZ!Box 4020 */
 	ATH79_MACH_GL_AR150,			/* GL-AR150 support */
 	ATH79_MACH_GL_AR300,			/* GL-AR300 */
 	ATH79_MACH_GL_AR300M,			/* GL-AR300M */
diff --git a/target/linux/ar71xx/generic/config-default b/target/linux/ar71xx/generic/config-default
index 6475d22..3f93d6e 100644
--- a/target/linux/ar71xx/generic/config-default
+++ b/target/linux/ar71xx/generic/config-default
@@ -88,6 +88,7 @@ CONFIG_ATH79_MACH_EW_BALIN=y
 CONFIG_ATH79_MACH_EW_DORIN=y
 CONFIG_ATH79_MACH_F9K1115V2=y
 CONFIG_ATH79_MACH_FRITZ300E=y
+CONFIG_ATH79_MACH_FRITZ4020=y
 CONFIG_ATH79_MACH_GL_AR150=y
 CONFIG_ATH79_MACH_GL_AR300=y
 CONFIG_ATH79_MACH_GL_AR300M=y
diff --git a/target/linux/ar71xx/image/generic.mk b/target/linux/ar71xx/image/generic.mk
index 0d3aedb..a0f6326 100644
--- a/target/linux/ar71xx/image/generic.mk
+++ b/target/linux/ar71xx/image/generic.mk
@@ -1282,16 +1282,31 @@ define Device/zbt-we1526
 endef
 TARGET_DEVICES += zbt-we1526
 
-define Device/fritz300e
-  DEVICE_TITLE := AVM FRITZ!WLAN Repeater 300E
-  DEVICE_PACKAGES := fritz-tffs rssileds -swconfig -uboot-envtools
-  BOARDNAME := FRITZ300E
-  SUPPORTED_DEVICES := fritz300e
-  IMAGE_SIZE := 15232k
+define Device/AVM
+  DEVICE_PACKAGES := fritz-tffs -uboot-envtools
   KERNEL := kernel-bin | patch-cmdline | lzma | eva-image
   KERNEL_INITRAMFS := $$(KERNEL)
   IMAGE/sysupgrade.bin := append-kernel | pad-to 64k | \
 	append-squashfs-fakeroot-be | pad-to 256 | \
 	append-rootfs | pad-rootfs | append-metadata | check-size $$$$(IMAGE_SIZE)
 endef
+
+define Device/fritz300e
+  $(call Device/AVM)
+  DEVICE_TITLE := AVM FRITZ!WLAN Repeater 300E
+  DEVICE_PACKAGES := rssileds -swconfig
+  BOARDNAME := FRITZ300E
+  SUPPORTED_DEVICES := fritz300e
+  IMAGE_SIZE := 15232k
+endef
 TARGET_DEVICES += fritz300e
+
+define Device/fritz4020
+  $(call Device/AVM)
+  DEVICE_TITLE := AVM FRITZ!Box 4020
+  DEVICE_PACKAGES := kmod-usb-core kmod-usb2 kmod-usb-storage
+  BOARDNAME := FRITZ4020
+  SUPPORTED_DEVICES := fritz4020
+  IMAGE_SIZE := 15232k
+endef
+TARGET_DEVICES += fritz4020