diff --git a/.drone.yml b/.drone.yml
index fddf3f5..df59b4e 100644
--- a/.drone.yml
+++ b/.drone.yml
@@ -16,7 +16,7 @@ steps:
     DEBIAN_FRONTEND: noninteractive
   commands:
   - apt-get update
-  - apt-get install -y build-essential
+  - apt-get install -y sed make binutils build-essential diffutils gcc g++ bash patch gzip bzip2 perl tar cpio unzip rsync file bc findutils wget
 
 - name: Configure
   commands:
diff --git a/buildroot b/buildroot
index dbb0b42..87e979e 160000
--- a/buildroot
+++ b/buildroot
@@ -1 +1 @@
-Subproject commit dbb0b4274cdbd74cf22fb4da4c1e43084f3d3125
+Subproject commit 87e979e4572449ecb7d2058b02d642b38cc3b0f8
diff --git a/external_tree/board/iminc/orangepi-pc-sx1302-hat/boot.cmd b/external_tree/board/iminc/orangepi-pc-sx1302-hat/boot.cmd
deleted file mode 100644
index f12a258..0000000
--- a/external_tree/board/iminc/orangepi-pc-sx1302-hat/boot.cmd
+++ /dev/null
@@ -1,18 +0,0 @@
-setenv bootargs console=ttyS0,115200 earlyprintk root=/dev/mmcblk0p2 rootwait
-
-fatload mmc 0 ${kernel_addr_r} zImage
-fatload mmc 0 ${fdt_addr_r} ${fdtfile}
-
-fdt addr ${fdt_addr_r}
-fdt resize 32768
-
-fdt set /soc/serial@1c28c00 status okay
-
-fdt set /soc/spi@1c68000 status okay
-fdt mknode /soc/spi@1c68000 spidev@0
-fdt set /soc/spi@1c68000/spidev@0 status "okay"
-fdt set /soc/spi@1c68000/spidev@0 reg <0>
-fdt set /soc/spi@1c68000/spidev@0 spi-max-frequency <10000000>
-fdt set /soc/spi@1c68000/spidev@0 compatible "semtech,sx1301"
-
-bootz ${kernel_addr_r} - ${fdt_addr_r}
diff --git a/external_tree/board/iminc/orangepi-pc-sx1302-hat/linux.fragment b/external_tree/board/iminc/orangepi-pc-sx1302-hat/linux.fragment
deleted file mode 100644
index 18adbe2..0000000
--- a/external_tree/board/iminc/orangepi-pc-sx1302-hat/linux.fragment
+++ /dev/null
@@ -1,4 +0,0 @@
-CONFIG_CPU_FREQ_DEFAULT_GOV_ONDEMAND=y
-CONFIG_REGULATOR_SY8106A=y
-CONFIG_SPI_SPIDEV=y
-CONFIG_SUN8I_DE2_CCU=y
diff --git a/external_tree/board/iminc/orangepi-pc-sx1302-hat/readme.txt b/external_tree/board/iminc/orangepi-pc-sx1302-hat/readme.txt
deleted file mode 100644
index d316b6f..0000000
--- a/external_tree/board/iminc/orangepi-pc-sx1302-hat/readme.txt
+++ /dev/null
@@ -1,29 +0,0 @@
-OrangePi PC
-
-Intro
-=====
-
-This default configuration will allow you to start experimenting with the
-buildroot environment for the OrangePi PC. With the current configuration
-it will bring-up the board, and allow access through the serial console.
-
-How to build it
-===============
-
-Configure Buildroot:
-
-    $ make orangepi_pc_defconfig
-
-Compile everything and build the SD card image:
-
-    $ make
-
-How to write the SD card
-========================
-
-Once the build process is finished you will have an image called "sdcard.img"
-in the output/images/ directory.
-
-Copy the bootable "sdcard.img" onto an SD card with "dd":
-
-  $ sudo dd if=output/images/sdcard.img of=/dev/sdX
diff --git a/external_tree/board/rpi2b/cmdline.txt b/external_tree/board/rpi2b/cmdline.txt
new file mode 100644
index 0000000..9369d27
--- /dev/null
+++ b/external_tree/board/rpi2b/cmdline.txt
@@ -0,0 +1 @@
+root=/dev/mmcblk0p2 rootwait console=tty1
diff --git a/external_tree/board/rpi2b/config.txt b/external_tree/board/rpi2b/config.txt
new file mode 100644
index 0000000..67e24bf
--- /dev/null
+++ b/external_tree/board/rpi2b/config.txt
@@ -0,0 +1,42 @@
+# Please note that this is only a sample, we recommend you to change it to fit
+# your needs.
+# You should override this file using BR2_PACKAGE_RPI_FIRMWARE_CONFIG_FILE.
+# See http://buildroot.org/manual.html#rootfs-custom
+# and http://elinux.org/RPiconfig for a description of config.txt syntax
+
+start_file=start.elf
+fixup_file=fixup.dat
+
+kernel=zImage
+
+# To use an external initramfs file
+#initramfs rootfs.cpio.gz
+
+# Disable overscan assuming the display supports displaying the full resolution
+# If the text shown on the screen disappears off the edge, comment this out
+disable_overscan=1
+
+# How much memory in MB to assign to the GPU on Pi models having
+# 256, 512 or 1024 MB total memory
+gpu_mem_256=100
+gpu_mem_512=100
+gpu_mem_1024=100
+
+# Set I2C speed to 400kHz(Fast mode)
+dtparam=i2c_arm=on,i2c_arm_baudrate=400000
+
+# Enable spidev node
+dtparam=spi=on
+
+# Add PCF8574A GPIO expander
+dtoverlay=pcf857x,pcf8574a,addr=0x38,interrupt=22
+
+# Add DS3231 driver
+dtoverlay=i2c-rtc,ds3231
+
+# Add BME280 sensor
+dtoverlay=i2c-sensor,bme280,addr=0x76
+
+# PPS signal
+dtoverlay=pps-gpio,gpiopin=17,capture_clear
+
diff --git a/external_tree/board/iminc/orangepi-pc-sx1302-hat/genimage.cfg b/external_tree/board/rpi2b/genimage.cfg.in
similarity index 50%
rename from external_tree/board/iminc/orangepi-pc-sx1302-hat/genimage.cfg
rename to external_tree/board/rpi2b/genimage.cfg.in
index 23c17ab..fd38b86 100644
--- a/external_tree/board/iminc/orangepi-pc-sx1302-hat/genimage.cfg
+++ b/external_tree/board/rpi2b/genimage.cfg.in
@@ -1,13 +1,10 @@
-# Minimal SD card image for the OrangePi PC
-#
 image boot.vfat {
 	vfat {
 		files = {
-			"zImage",
-			"sun8i-h3-orangepi-pc.dtb",
-			"boot.scr"
+#BOOT_FILES#
 		}
 	}
+
 	size = 32M
 }
 
@@ -15,13 +12,6 @@ image sdcard.img {
 	hdimage {
 	}
 
-	partition u-boot {
-		in-partition-table = "no"
-		image = "u-boot-sunxi-with-spl.bin"
-		offset = 8192
-		size = 1040384 # 1MB - 8192
-	}
-
 	partition boot {
 		partition-type = 0xC
 		bootable = "true"
@@ -31,6 +21,5 @@ image sdcard.img {
 	partition rootfs {
 		partition-type = 0x83
 		image = "rootfs.ext4"
-		size = 128M
 	}
 }
diff --git a/external_tree/board/iminc/orangepi-pc-sx1302-hat/uboot.fragment b/external_tree/board/rpi2b/linux.fragment
similarity index 100%
rename from external_tree/board/iminc/orangepi-pc-sx1302-hat/uboot.fragment
rename to external_tree/board/rpi2b/linux.fragment
diff --git a/external_tree/board/rpi2b/post-build.sh b/external_tree/board/rpi2b/post-build.sh
new file mode 100755
index 0000000..73026e5
--- /dev/null
+++ b/external_tree/board/rpi2b/post-build.sh
@@ -0,0 +1,16 @@
+#!/bin/sh
+
+set -u
+set -e
+
+# Add a console on tty1
+if [ -e ${TARGET_DIR}/etc/inittab ]; then
+    grep -qE '^tty1::' ${TARGET_DIR}/etc/inittab || \
+	sed -i '/GENERIC_SERIAL/a\
+tty1::respawn:/sbin/getty -L  tty1 0 vt100 # HDMI console' ${TARGET_DIR}/etc/inittab
+# systemd doesn't use /etc/inittab, enable getty.tty1.service instead
+elif [ -d ${TARGET_DIR}/etc/systemd ]; then
+    mkdir -p "${TARGET_DIR}/etc/systemd/system/getty.target.wants"
+    ln -sf /lib/systemd/system/getty@.service \
+       "${TARGET_DIR}/etc/systemd/system/getty.target.wants/getty@tty1.service"
+fi
diff --git a/external_tree/board/rpi2b/post-image.sh b/external_tree/board/rpi2b/post-image.sh
new file mode 100755
index 0000000..9b9eac9
--- /dev/null
+++ b/external_tree/board/rpi2b/post-image.sh
@@ -0,0 +1,44 @@
+#!/bin/bash
+
+set -e
+
+BOARD_DIR="$(dirname $0)"
+BOARD_NAME="$(basename ${BOARD_DIR})"
+GENIMAGE_CFG="${BOARD_DIR}/genimage-${BOARD_NAME}.cfg"
+GENIMAGE_TMP="${BUILD_DIR}/genimage.tmp"
+
+# generate genimage from template if a board specific variant doesn't exists
+if [ ! -e "${GENIMAGE_CFG}" ]; then
+	GENIMAGE_CFG="${BINARIES_DIR}/genimage.cfg"
+	FILES=()
+
+	for i in "${BINARIES_DIR}"/*.dtb "${BINARIES_DIR}"/rpi-firmware/*; do
+		FILES+=( "${i#${BINARIES_DIR}/}" )
+	done
+
+	KERNEL=$(sed -n 's/^kernel=//p' "${BINARIES_DIR}/rpi-firmware/config.txt")
+	FILES+=( "${KERNEL}" )
+
+	BOOT_FILES=$(printf '\\t\\t\\t"%s",\\n' "${FILES[@]}")
+	sed "s|#BOOT_FILES#|${BOOT_FILES}|" "${BOARD_DIR}/genimage.cfg.in" \
+		> "${GENIMAGE_CFG}"
+fi
+
+# Pass an empty rootpath. genimage makes a full copy of the given rootpath to
+# ${GENIMAGE_TMP}/root so passing TARGET_DIR would be a waste of time and disk
+# space. We don't rely on genimage to build the rootfs image, just to insert a
+# pre-built one in the disk image.
+
+trap 'rm -rf "${ROOTPATH_TMP}"' EXIT
+ROOTPATH_TMP="$(mktemp -d)"
+
+rm -rf "${GENIMAGE_TMP}"
+
+genimage \
+	--rootpath "${ROOTPATH_TMP}"   \
+	--tmppath "${GENIMAGE_TMP}"    \
+	--inputpath "${BINARIES_DIR}"  \
+	--outputpath "${BINARIES_DIR}" \
+	--config "${GENIMAGE_CFG}"
+
+exit $?
diff --git a/external_tree/board/rpi2b/readme.txt b/external_tree/board/rpi2b/readme.txt
new file mode 100644
index 0000000..9202b5f
--- /dev/null
+++ b/external_tree/board/rpi2b/readme.txt
@@ -0,0 +1,162 @@
+Raspberry Pi
+
+Intro
+=====
+
+These instructions apply to all models of the Raspberry Pi:
+  - the original models A and B,
+  - the "enhanced" models A+ and B+,
+  - the model B2 (aka Raspberry Pi 2)
+  - the model B3 (aka Raspberry Pi 3).
+  - the model B4 (aka Raspberry Pi 4).
+  - the model CM4 (aka Raspberry Pi Compute Module 4 and IO Board).
+
+How to build it
+===============
+
+Configure Buildroot
+-------------------
+
+There are several Raspberry Pi defconfig files in Buildroot, one for
+each major variant, which you should base your work on:
+
+For models A, B, A+ or B+:
+
+  $ make raspberrypi_defconfig
+
+For model Zero (model A+ in smaller form factor):
+
+  $ make raspberrypi0_defconfig
+
+or for model Zero W (model Zero with wireless LAN and Bluetooth):
+
+  $ make raspberrypi0w_defconfig
+
+For model Zero 2 W (model B3 in smaller form factor):
+
+  $ make raspberrypizero2w_defconfig
+
+For model 2 B:
+
+  $ make raspberrypi2_defconfig
+
+For model 3 B and B+:
+
+  $ make raspberrypi3_defconfig
+
+or for model 3 B and B+ (64 bit):
+
+  $ make raspberrypi3_64_defconfig
+
+For model 4 B:
+
+  $ make raspberrypi4_defconfig
+
+or for model 4 B (64 bit):
+
+  $ make raspberrypi4_64_defconfig
+
+For model CM4 (on IO Board):
+
+  $ make raspberrypicm4io_defconfig
+
+or for CM4 (on IO Board - 64 bit):
+
+  $ make raspberrypicm4io_64_defconfig
+
+Build the rootfs
+----------------
+
+Note: you will need to have access to the network, since Buildroot will
+download the packages' sources.
+
+You may now build your rootfs with:
+
+  $ make
+
+(This may take a while, consider getting yourself a coffee ;-) )
+
+Result of the build
+-------------------
+
+After building, you should obtain this tree:
+
+    output/images/
+    +-- bcm2708-rpi-b.dtb           [1]
+    +-- bcm2708-rpi-b-plus.dtb      [1]
+    +-- bcm2708-rpi-cm.dtb          [1]
+    +-- bcm2708-rpi-zero.dtb        [1]
+    +-- bcm2708-rpi-zero-w.dtb      [1]
+    +-- bcm2710-rpi-zero-2-w.dtb    [1]
+    +-- bcm2709-rpi-2-b.dtb         [1]
+    +-- bcm2710-rpi-3-b.dtb         [1]
+    +-- bcm2710-rpi-3-b-plus.dtb    [1]
+    +-- bcm2710-rpi-cm3.dtb         [1]
+    +-- bcm2711-rpi-4-b.dtb         [1]
+    +-- bcm2711-rpi-cm4.dtb         [1]
+    +-- bcm2837-rpi-3-b.dtb         [1]
+    +-- boot.vfat
+    +-- rootfs.ext4
+    +-- rpi-firmware/
+    |   +-- bootcode.bin
+    |   +-- cmdline.txt
+    |   +-- config.txt
+    |   +-- fixup.dat               [1]
+    |   +-- fixup4.dat              [1]
+    |   +-- start.elf               [1]
+    |   +-- start4.elf              [1]
+    |   `-- overlays/               [2]
+    +-- sdcard.img
+    +-- Image                       [1]
+    `-- zImage                      [1]
+
+[1] Not all of them will be present, depending on the RaspberryPi
+    model you are using.
+
+[2] Only for the Raspberry Pi 3/4 Models (overlay miniuart-bt is needed
+    to enable the RPi3 serial console otherwise occupied by the bluetooth
+    chip). Alternative would be to disable the serial console in cmdline.txt
+    and /etc/inittab.
+
+How to write the SD card
+========================
+
+Once the build process is finished you will have an image called "sdcard.img"
+in the output/images/ directory.
+
+Copy the bootable "sdcard.img" onto an SD card with "dd":
+
+  $ sudo dd if=output/images/sdcard.img of=/dev/sdX
+
+Insert the SDcard into your Raspberry Pi, and power it up. Your new system
+should come up now and start two consoles: one on the serial port on
+the P1 header, one on the HDMI output where you can login using a USB
+keyboard.
+
+How to write to CM4 eMMC memory
+===============================
+
+For CM4 modules without eMMC memory see above for booting from SD card,
+for CM4 modules with eMMC memory proceed as following:
+
+- fit jumper on IO Board header J2 to disable eMMC boot
+- connect IO Board micro USB port (J11 USB slave) to your host linux system
+- power up CM4/IO Board (lsusb command should show a '0a5c:2711 Broadcom Corp.
+  BCM2711 Boot' device)
+- run 'sudo ./host/bin/rpiboot', output should look like the following:
+    Waiting for BCM2835/6/7/2711...
+    Loading embedded: bootcode4.bin
+    Sending bootcode.bin
+    Successful read 4 bytes
+    Waiting for BCM2835/6/7/2711...
+    Loading embedded: bootcode4.bin
+    Second stage boot server
+    Loading embedded: start4.elf
+    File read: start4.elf
+    Second stage boot server done
+
+- a USB mass storage device should show up (the CM4 eMMC memory), proceed
+  as described above to copy sdcard.img to it
+- power down CM4/IO Board
+- remove jumper on IO Board header J2 to re-enable eMMC boot
+- power up CM4/IO Board
diff --git a/external_tree/configs/lwgw_orangepi_pc_defconfig b/external_tree/configs/lwgw_orangepi_pc_defconfig
deleted file mode 100644
index b843d5e..0000000
--- a/external_tree/configs/lwgw_orangepi_pc_defconfig
+++ /dev/null
@@ -1,108 +0,0 @@
-BR2_arm=y
-BR2_cortex_a7=y
-BR2_ARM_FPU_NEON_VFPV4=y
-BR2_PACKAGE_GLIBC_UTILS=y
-BR2_BINUTILS_VERSION_2_39_X=y
-BR2_GCC_VERSION_12_X=y
-BR2_TOOLCHAIN_BUILDROOT_CXX=y
-BR2_PACKAGE_HOST_GDB=y
-BR2_PACKAGE_HOST_GDB_TUI=y
-BR2_PACKAGE_HOST_GDB_PYTHON3=y
-BR2_GDB_VERSION_12=y
-BR2_DL_DIR="$(HOME)/Softwares/Buildroot/dl"
-BR2_CCACHE=y
-BR2_CCACHE_DIR="$(HOME)/Softwares/Buildroot/ccache"
-BR2_CCACHE_INITIAL_SETUP="-M 20G"
-BR2_ENABLE_DEBUG=y
-BR2_OPTIMIZE_G=y
-BR2_TARGET_GENERIC_HOSTNAME="lwgw-opi-pc"
-BR2_TARGET_GENERIC_ISSUE="ARE U OKAY ?"
-BR2_INIT_SYSTEMD=y
-# BR2_TARGET_ENABLE_ROOT_LOGIN is not set
-BR2_SYSTEM_BIN_SH_BASH=y
-BR2_SYSTEM_DEFAULT_PATH="/bin:/sbin:/usr/bin:/usr/sbin"
-BR2_GENERATE_LOCALE="en_US.UTF-8"
-BR2_TARGET_LOCALTIME="Asia/Tokyo"
-BR2_ROOTFS_USERS_TABLES="$(BR2_EXTERNAL_lwgw_PATH)/customizations/users.table"
-BR2_ROOTFS_OVERLAY="$(BR2_EXTERNAL_lwgw_PATH)/customizations/overlay"
-BR2_ROOTFS_POST_IMAGE_SCRIPT="support/scripts/genimage.sh"
-BR2_ROOTFS_POST_SCRIPT_ARGS="-c $(BR2_EXTERNAL_lwgw_PATH)/board/iminc/orangepi-pc-sx1302-hat/genimage.cfg"
-BR2_LINUX_KERNEL=y
-BR2_LINUX_KERNEL_CUSTOM_VERSION=y
-BR2_LINUX_KERNEL_CUSTOM_VERSION_VALUE="6.3.10"
-BR2_LINUX_KERNEL_DEFCONFIG="sunxi"
-BR2_LINUX_KERNEL_CONFIG_FRAGMENT_FILES="$(BR2_EXTERNAL_lwgw_PATH)/board/iminc/orangepi-pc-sx1302-hat/linux.fragment"
-BR2_LINUX_KERNEL_DTS_SUPPORT=y
-BR2_LINUX_KERNEL_INTREE_DTS_NAME="sun8i-h3-orangepi-pc"
-BR2_PACKAGE_LINUX_TOOLS_CPUPOWER=y
-BR2_PACKAGE_LINUX_TOOLS_GPIO=y
-BR2_PACKAGE_LINUX_TOOLS_IIO=y
-BR2_PACKAGE_E2FSPROGS=y
-BR2_PACKAGE_E2FSPROGS_E4DEFRAG=y
-BR2_PACKAGE_E2FSPROGS_RESIZE2FS=y
-BR2_PACKAGE_GPSD=y
-BR2_PACKAGE_GPSD_DEVICES="/dev/ttyS3"
-BR2_PACKAGE_GPSD_CLIENT_DEBUG=y
-BR2_PACKAGE_GPSD_PROFILING=y
-BR2_PACKAGE_GPSD_USER=y
-BR2_PACKAGE_GPSD_GROUP=y
-BR2_PACKAGE_GPSD_UBX=y
-BR2_PACKAGE_GPTFDISK=y
-BR2_PACKAGE_GPTFDISK_GDISK=y
-BR2_PACKAGE_GPTFDISK_SGDISK=y
-BR2_PACKAGE_I2C_TOOLS=y
-BR2_PACKAGE_SPI_TOOLS=y
-BR2_PACKAGE_UBOOT_TOOLS=y
-BR2_PACKAGE_UBOOT_TOOLS_FIT_SUPPORT=y
-BR2_PACKAGE_UBOOT_TOOLS_MKIMAGE=y
-BR2_PACKAGE_UBOOT_TOOLS_MKENVIMAGE=y
-BR2_PACKAGE_UBOOT_TOOLS_DUMPIMAGE=y
-BR2_PACKAGE_LIBOPENSSL_BIN=y
-BR2_PACKAGE_LIBOPENSSL_ENGINES=y
-BR2_PACKAGE_LIBCONFIG=y
-BR2_PACKAGE_LIBGPIOD=y
-BR2_PACKAGE_LIBGPIOD_TOOLS=y
-BR2_PACKAGE_LIBIIO=y
-# BR2_PACKAGE_LIBIIO_IIOD is not set
-BR2_PACKAGE_LIBIIO_TESTS=y
-BR2_PACKAGE_LIBCURL=y
-BR2_PACKAGE_LIBCURL_CURL=y
-BR2_PACKAGE_MOSQUITTO=y
-# BR2_PACKAGE_MOSQUITTO_BROKER is not set
-BR2_PACKAGE_NETWORK_MANAGER=y
-BR2_PACKAGE_NETWORK_MANAGER_TUI=y
-BR2_PACKAGE_NETWORK_MANAGER_MODEM_MANAGER=y
-BR2_PACKAGE_OPENSSH=y
-BR2_PACKAGE_WPA_SUPPLICANT=y
-BR2_PACKAGE_WPA_SUPPLICANT_AUTOSCAN=y
-BR2_PACKAGE_WPA_SUPPLICANT_WPA3=y
-BR2_PACKAGE_WPA_SUPPLICANT_CLI=y
-BR2_PACKAGE_WPA_SUPPLICANT_WPA_CLIENT_SO=y
-BR2_PACKAGE_WPA_SUPPLICANT_DBUS=y
-BR2_PACKAGE_WPA_SUPPLICANT_DBUS_INTROSPECTION=y
-BR2_PACKAGE_BASH_COMPLETION=y
-BR2_PACKAGE_FILE=y
-BR2_PACKAGE_SUDO=y
-BR2_PACKAGE_COREUTILS=y
-BR2_PACKAGE_HTOP=y
-BR2_PACKAGE_UTIL_LINUX_HWCLOCK=y
-BR2_PACKAGE_VIM=y
-BR2_TARGET_ROOTFS_EXT2=y
-BR2_TARGET_ROOTFS_EXT2_4=y
-BR2_TARGET_ROOTFS_EXT2_SIZE="128M"
-# BR2_TARGET_ROOTFS_TAR is not set
-BR2_TARGET_UBOOT=y
-BR2_TARGET_UBOOT_BUILD_SYSTEM_KCONFIG=y
-BR2_TARGET_UBOOT_CUSTOM_VERSION=y
-BR2_TARGET_UBOOT_CUSTOM_VERSION_VALUE="2023.04"
-BR2_TARGET_UBOOT_BOARD_DEFCONFIG="orangepi_pc"
-BR2_TARGET_UBOOT_NEEDS_DTC=y
-BR2_TARGET_UBOOT_NEEDS_PYLIBFDT=y
-BR2_TARGET_UBOOT_FORMAT_CUSTOM=y
-BR2_TARGET_UBOOT_FORMAT_CUSTOM_NAME="u-boot-sunxi-with-spl.bin"
-BR2_PACKAGE_HOST_DOSFSTOOLS=y
-BR2_PACKAGE_HOST_GENIMAGE=y
-BR2_PACKAGE_HOST_MTOOLS=y
-BR2_PACKAGE_HOST_UBOOT_TOOLS=y
-BR2_PACKAGE_HOST_UBOOT_TOOLS_BOOT_SCRIPT=y
-BR2_PACKAGE_HOST_UBOOT_TOOLS_BOOT_SCRIPT_SOURCE="$(BR2_EXTERNAL_lwgw_PATH)/board/iminc/orangepi-pc-sx1302-hat/boot.cmd"
diff --git a/external_tree/configs/rpi2_defconfig b/external_tree/configs/rpi2_defconfig
new file mode 100644
index 0000000..0ab63f1
--- /dev/null
+++ b/external_tree/configs/rpi2_defconfig
@@ -0,0 +1,38 @@
+BR2_arm=y
+BR2_cortex_a7=y
+BR2_BINUTILS_VERSION_2_41_X=y
+BR2_GCC_VERSION_13_X=y
+BR2_TOOLCHAIN_BUILDROOT_CXX=y
+BR2_PACKAGE_HOST_GDB=y
+BR2_PACKAGE_HOST_GDB_TUI=y
+BR2_GDB_VERSION_13=y
+BR2_TARGET_GENERIC_HOSTNAME="pudding-lwgw-rpi2"
+BR2_TARGET_GENERIC_ISSUE="What GW?"
+BR2_INIT_SYSTEMD=y
+# BR2_TARGET_ENABLE_ROOT_LOGIN is not set
+BR2_SYSTEM_BIN_SH_BASH=y
+BR2_SYSTEM_DHCP="eth0"
+BR2_GENERATE_LOCALE="en_US.UTF-8"
+BR2_TARGET_LOCALTIME="Asia/Shanghai"
+BR2_ROOTFS_USERS_TABLES="$(BR2_EXTERNAL_lwgw_PATH)/customizations/users.table"
+BR2_ROOTFS_OVERLAY="$(BR2_EXTERNAL_lwgw_PATH)/customizations/overlay"
+BR2_LINUX_KERNEL=y
+BR2_LINUX_KERNEL_CUSTOM_GIT=y
+BR2_LINUX_KERNEL_CUSTOM_REPO_URL="https://github.com/raspberrypi/linux.git"
+BR2_LINUX_KERNEL_CUSTOM_REPO_VERSION="fc20eb4e650bf793bd6b3d804a63b67085c55f08"
+BR2_LINUX_KERNEL_PATCH="$(BR2_EXTERNAL_lwgw_PATH)/patches/kernel"
+BR2_LINUX_KERNEL_DEFCONFIG="bcm2709"
+BR2_LINUX_KERNEL_CONFIG_FRAGMENT_FILES="$(BR2_EXTERNAL_lwgw_PATH)/board/rpi2b/linux.fragment"
+BR2_LINUX_KERNEL_DTS_SUPPORT=y
+BR2_LINUX_KERNEL_INTREE_DTS_NAME="bcm2709-rpi-2-b"
+BR2_LINUX_KERNEL_DTB_OVERLAY_SUPPORT=y
+BR2_LINUX_KERNEL_INSTALL_TARGET=y
+BR2_PACKAGE_RPI_FIRMWARE=y
+BR2_PACKAGE_RPI_FIRMWARE_BOOTCODE_BIN=y
+BR2_PACKAGE_RPI_FIRMWARE_VARIANT_PI=y
+BR2_PACKAGE_RPI_FIRMWARE_CONFIG_FILE="$(BR2_EXTERNAL_lwgw_PATH)/board/rpi2b/config.txt"
+BR2_PACKAGE_I2C_TOOLS=y
+BR2_PACKAGE_SYSSTAT=y
+BR2_PACKAGE_OPENSSH=y
+BR2_PACKAGE_SUDO=y
+BR2_PACKAGE_HTOP=y
diff --git a/external_tree/customizations/overlay/etc/chrony.conf b/external_tree/customizations/overlay/etc/chrony.conf
new file mode 100644
index 0000000..5a3fe5b
--- /dev/null
+++ b/external_tree/customizations/overlay/etc/chrony.conf
@@ -0,0 +1,8 @@
+pool cn.pool.ntp.org            iburst maxsources 4
+pool ntp.nict.jp                iburst maxsources 4
+
+server ntp.tuna.tsinghua.edu.cn iburst
+
+refclock PPS /dev/pps0 lock NMEA refid GPS
+refclock SHM 0 offset 0.2 delay 0.1 refid NMEA noselect
+
diff --git a/external_tree/customizations/overlay/etc/default/gpsd b/external_tree/customizations/overlay/etc/default/gpsd
new file mode 100644
index 0000000..fac3973
--- /dev/null
+++ b/external_tree/customizations/overlay/etc/default/gpsd
@@ -0,0 +1,3 @@
+DEVICES="/dev/ttyAMA0 /dev/pps0"
+GPSD_OPTIONS="-n -G"
+
diff --git a/external_tree/customizations/overlay/etc/systemd/journald.conf b/external_tree/customizations/overlay/etc/systemd/journald.conf
new file mode 100644
index 0000000..b69850d
--- /dev/null
+++ b/external_tree/customizations/overlay/etc/systemd/journald.conf
@@ -0,0 +1,2 @@
+[Journal]
+Storage=volatile