diff --git a/resources/boot.cmd b/resources/boot.cmd
index eae7524..37b4004 100644
--- a/resources/boot.cmd
+++ b/resources/boot.cmd
@@ -83,16 +83,25 @@ echo "select kernel"
 setenv boot_kernel "/boot/uImage"
 
 # only if new pi a new kernel is required
+# https://www.raspberrypi.org/documentation/hardware/raspberrypi/revision-codes/README.md
 setexpr board_new_pi ${board_revision} \& 0x800000
 if test ${board_new_pi} > 0; then
   echo "new board"
   # get cpu id from revision
   setexpr board_cpu ${board_revision} \& 0xF000
   
-  # at the moment CPU except the oldest need the new kernel
-  if test ${board_cpu} > 0x0000; then
+  # BCM2836 (pi2)
+  if test ${board_cpu} == 0x1000; then
     setenv boot_kernel "/boot/uImage2"
   fi
+  # BCM2837 (pi3)
+  if test ${board_cpu} == 0x2000; then
+    setenv boot_kernel "/boot/uImage2"
+  fi
+  # BCM2711 (pi4)
+  if test ${board_cpu} > 0x3000; then
+    setenv boot_kernel "/boot/uImage4"
+  fi
 else
   echo "old board"
 fi
diff --git a/resources/build.sh b/resources/build.sh
index 4aee450..2d81d5c 100755
--- a/resources/build.sh
+++ b/resources/build.sh
@@ -28,7 +28,7 @@ set -e
 # static config
 # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
 RES_PATH=/resources/
-BASE_PACKAGES="alpine-base tzdata parted ifupdown e2fsprogs-extra util-linux coreutils linux-rpi linux-rpi2"
+BASE_PACKAGES="alpine-base tzdata parted ifupdown e2fsprogs-extra util-linux coreutils linux-rpi linux-rpi2 linux-rpi4"
 
 WORK_PATH="/work"
 ROOTFS_PATH="${WORK_PATH}/root_fs"
@@ -77,7 +77,7 @@ cp /usr/share/apk/keys/*.rsa.pub ${ROOTFS_PATH}/etc/apk/keys/
 cp /etc/apk/repositories ${ROOTFS_PATH}/etc/apk/repositories
 
 # initial package installation
-apk --root ${ROOTFS_PATH} --update-cache --initdb --arch armhf add $BASE_PACKAGES
+apk --root ${ROOTFS_PATH} --update-cache --initdb --arch armv7 add $BASE_PACKAGES
 
 # add google DNS to enable network access inside chroot
 echo "nameserver 8.8.8.8" > ${ROOTFS_PATH}/etc/resolv.conf
@@ -251,7 +251,7 @@ echo ">> Prepare kernel for uboot"
 # build uImage
 mkimage -A arm -O linux -T kernel -C none -a 0x00008000 -e 0x00008000 -n "Linux kernel" -d ${ROOTFS_PATH}/boot/vmlinuz-rpi ${ROOTFS_PATH}/boot/uImage 
 mkimage -A arm -O linux -T kernel -C none -a 0x00008000 -e 0x00008000 -n "Linux kernel" -d ${ROOTFS_PATH}/boot/vmlinuz-rpi2 ${ROOTFS_PATH}/boot/uImage2
-
+mkimage -A arm -O linux -T kernel -C none -a 0x00008000 -e 0x00008000 -n "Linux kernel" -d ${ROOTFS_PATH}/boot/vmlinuz-rpi4 ${ROOTFS_PATH}/boot/uImage4
 
 # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # # #
 # create boot FS