diff --git a/root/include/kernel-defaults.mk b/root/include/kernel-defaults.mk
new file mode 100644
index 00000000..307c7b5d
--- /dev/null
+++ b/root/include/kernel-defaults.mk
@@ -0,0 +1,202 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Copyright (C) 2006-2020 OpenWrt.org
+
+ifdef CONFIG_STRIP_KERNEL_EXPORTS
+  KERNEL_MAKEOPTS_IMAGE += \
+	EXTRA_LDSFLAGS="-I$(KERNEL_BUILD_DIR) -include symtab.h"
+endif
+
+INITRAMFS_EXTRA_FILES ?= $(GENERIC_PLATFORM_DIR)/image/initramfs-base-files.txt
+
+ifneq (,$(KERNEL_CC))
+  KERNEL_MAKEOPTS += CC="$(KERNEL_CC)"
+endif
+
+export HOST_EXTRACFLAGS=-I$(STAGING_DIR_HOST)/include
+
+# defined in quilt.mk
+Kernel/Patch:=$(Kernel/Patch/Default)
+
+ifneq (,$(findstring .xz,$(LINUX_SOURCE)))
+  LINUX_CAT:=xzcat
+else
+  LINUX_CAT:=gzip -dc
+endif
+
+ifeq ($(strip $(CONFIG_EXTERNAL_KERNEL_TREE)),"")
+  ifeq ($(strip $(CONFIG_KERNEL_GIT_CLONE_URI)),"")
+    define Kernel/Prepare/Default
+	$(LINUX_CAT) $(DL_DIR)/$(LINUX_SOURCE) | $(TAR) -C $(KERNEL_BUILD_DIR) $(TAR_OPTIONS)
+	$(Kernel/Patch)
+	$(if $(QUILT),touch $(LINUX_DIR)/.quilt_used)
+    endef
+  else
+    define Kernel/Prepare/Default
+	$(LINUX_CAT) $(DL_DIR)/$(LINUX_SOURCE) | $(TAR) -C $(KERNEL_BUILD_DIR) $(TAR_OPTIONS)
+    endef
+  endif
+else
+  define Kernel/Prepare/Default
+	mkdir -p $(KERNEL_BUILD_DIR)
+	if [ -d $(LINUX_DIR) ]; then \
+		rmdir $(LINUX_DIR); \
+	fi
+	ln -s $(CONFIG_EXTERNAL_KERNEL_TREE) $(LINUX_DIR)
+	if [ -d $(LINUX_DIR)/user_headers ]; then \
+		rm -rf $(LINUX_DIR)/user_headers; \
+	fi
+  endef
+endif
+
+ifeq ($(CONFIG_TARGET_ROOTFS_INITRAMFS),y)
+  ifeq ($(CONFIG_TARGET_ROOTFS_INITRAMFS_SEPARATE),y)
+    define Kernel/SetInitramfs/PreConfigure
+	grep -v -e CONFIG_BLK_DEV_INITRD $(LINUX_DIR)/.config.old > $(LINUX_DIR)/.config
+	echo 'CONFIG_BLK_DEV_INITRD=y' >> $(LINUX_DIR)/.config
+	echo 'CONFIG_INITRAMFS_SOURCE=""' >> $(LINUX_DIR)/.config
+    endef
+  else
+  ifeq ($(strip $(CONFIG_EXTERNAL_CPIO)),"")
+    define Kernel/SetInitramfs/PreConfigure
+	grep -v -e INITRAMFS -e CONFIG_RD_ -e CONFIG_BLK_DEV_INITRD $(LINUX_DIR)/.config.old > $(LINUX_DIR)/.config
+	echo 'CONFIG_BLK_DEV_INITRD=y' >> $(LINUX_DIR)/.config
+	echo 'CONFIG_INITRAMFS_SOURCE="$(strip $(TARGET_DIR) $(INITRAMFS_EXTRA_FILES))"' >> $(LINUX_DIR)/.config
+    endef
+  else
+    define Kernel/SetInitramfs/PreConfigure
+	grep -v INITRAMFS $(LINUX_DIR)/.config.old > $(LINUX_DIR)/.config
+	echo 'CONFIG_INITRAMFS_SOURCE="$(call qstrip,$(CONFIG_EXTERNAL_CPIO))"' >> $(LINUX_DIR)/.config
+    endef
+  endif
+endif
+
+  define Kernel/SetInitramfs
+	rm -f $(LINUX_DIR)/.config.prev
+	mv $(LINUX_DIR)/.config $(LINUX_DIR)/.config.old
+	$(call Kernel/SetInitramfs/PreConfigure)
+	echo "# CONFIG_INITRAMFS_PRESERVE_MTIME is not set" >> $(LINUX_DIR)/.config
+  ifneq ($(CONFIG_TARGET_ROOTFS_INITRAMFS_SEPARATE),y)
+	echo 'CONFIG_INITRAMFS_ROOT_UID=$(shell id -u)' >> $(LINUX_DIR)/.config
+	echo 'CONFIG_INITRAMFS_ROOT_GID=$(shell id -g)' >> $(LINUX_DIR)/.config
+	echo "$(if $(CONFIG_TARGET_INITRAMFS_FORCE),CONFIG_INITRAMFS_FORCE=y,# CONFIG_INITRAMFS_FORCE is not set)" >> $(LINUX_DIR)/.config
+  else
+	echo "# CONFIG_INITRAMFS_FORCE is not set" >> $(LINUX_DIR)/.config
+  endif
+	echo "$(if $(CONFIG_TARGET_INITRAMFS_COMPRESSION_NONE),CONFIG_INITRAMFS_COMPRESSION_NONE=y,# CONFIG_INITRAMFS_COMPRESSION_NONE is not set)" >> $(LINUX_DIR)/.config
+	echo -e "$(if $(CONFIG_TARGET_INITRAMFS_COMPRESSION_GZIP),CONFIG_INITRAMFS_COMPRESSION_GZIP=y\nCONFIG_RD_GZIP=y,# CONFIG_INITRAMFS_COMPRESSION_GZIP is not set\n# CONFIG_RD_GZIP is not set)" >> $(LINUX_DIR)/.config
+	echo -e "$(if $(CONFIG_TARGET_INITRAMFS_COMPRESSION_BZIP2),CONFIG_INITRAMFS_COMPRESSION_BZIP2=y\nCONFIG_RD_BZIP2=y,# CONFIG_INITRAMFS_COMPRESSION_BZIP2 is not set\n# CONFIG_RD_BZIP2 is not set)" >> $(LINUX_DIR)/.config
+	echo -e "$(if $(CONFIG_TARGET_INITRAMFS_COMPRESSION_LZMA),CONFIG_INITRAMFS_COMPRESSION_LZMA=y\nCONFIG_RD_LZMA=y,# CONFIG_INITRAMFS_COMPRESSION_LZMA is not set\n# CONFIG_RD_LZMA is not set)" >> $(LINUX_DIR)/.config
+	echo -e "$(if $(CONFIG_TARGET_INITRAMFS_COMPRESSION_LZO),CONFIG_INITRAMFS_COMPRESSION_LZO=y\nCONFIG_RD_LZO=y,# CONFIG_INITRAMFS_COMPRESSION_LZO is not set\n# CONFIG_RD_LZO is not set)" >> $(LINUX_DIR)/.config
+	echo -e "$(if $(CONFIG_TARGET_INITRAMFS_COMPRESSION_XZ),CONFIG_INITRAMFS_COMPRESSION_XZ=y\nCONFIG_RD_XZ=y,# CONFIG_INITRAMFS_COMPRESSION_XZ is not set\n# CONFIG_RD_XZ is not set)" >> $(LINUX_DIR)/.config
+	echo -e "$(if $(CONFIG_TARGET_INITRAMFS_COMPRESSION_LZ4),CONFIG_INITRAMFS_COMPRESSION_LZ4=y\nCONFIG_RD_LZ4=y,# CONFIG_INITRAMFS_COMPRESSION_LZ4 is not set\n# CONFIG_RD_LZ4 is not set)" >> $(LINUX_DIR)/.config
+	echo -e "$(if $(CONFIG_TARGET_INITRAMFS_COMPRESSION_ZSTD),CONFIG_INITRAMFS_COMPRESSION_ZSTD=y\nCONFIG_RD_ZSTD=y,# CONFIG_INITRAMFS_COMPRESSION_ZSTD is not set\n# CONFIG_RD_ZSTD is not set)" >> $(LINUX_DIR)/.config
+  endef
+else
+endif
+
+define Kernel/SetNoInitramfs
+	mv $(LINUX_DIR)/.config.set $(LINUX_DIR)/.config.old
+	grep -v INITRAMFS $(LINUX_DIR)/.config.old > $(LINUX_DIR)/.config.set
+	echo 'CONFIG_INITRAMFS_SOURCE=""' >> $(LINUX_DIR)/.config.set
+	echo '# CONFIG_INITRAMFS_FORCE is not set' >> $(LINUX_DIR)/.config.set
+	echo "# CONFIG_INITRAMFS_PRESERVE_MTIME is not set" >> $(LINUX_DIR)/.config.set
+endef
+
+define Kernel/Configure/Default
+	rm -f $(LINUX_DIR)/localversion
+	$(LINUX_CONF_CMD) > $(LINUX_DIR)/.config.target
+# copy CONFIG_KERNEL_* settings over to .config.target
+	awk '/^(#[[:space:]]+)?CONFIG_KERNEL/{sub("CONFIG_KERNEL_","CONFIG_");print}' $(TOPDIR)/.config >> $(LINUX_DIR)/.config.target
+	echo "# CONFIG_KALLSYMS_EXTRA_PASS is not set" >> $(LINUX_DIR)/.config.target
+	echo "# CONFIG_KALLSYMS_ALL is not set" >> $(LINUX_DIR)/.config.target
+	echo "CONFIG_KALLSYMS_UNCOMPRESSED=y" >> $(LINUX_DIR)/.config.target
+	$(SCRIPT_DIR)/package-metadata.pl kconfig $(TMP_DIR)/.packageinfo $(TOPDIR)/.config $(KERNEL_PATCHVER) > $(LINUX_DIR)/.config.override
+	$(SCRIPT_DIR)/kconfig.pl 'm+' '+' $(LINUX_DIR)/.config.target /dev/null $(LINUX_DIR)/.config.override > $(LINUX_DIR)/.config.set
+	$(call Kernel/SetNoInitramfs)
+	rm -rf $(KERNEL_BUILD_DIR)/modules
+	cmp -s $(LINUX_DIR)/.config.set $(LINUX_DIR)/.config.prev || { \
+		cp $(LINUX_DIR)/.config.set $(LINUX_DIR)/.config; \
+		cp $(LINUX_DIR)/.config.set $(LINUX_DIR)/.config.prev; \
+	}
+	$(_SINGLE) [ -d $(LINUX_DIR)/user_headers ] || $(KERNEL_MAKE) $(if $(findstring uml,$(BOARD)),ARCH=$(ARCH)) INSTALL_HDR_PATH=$(LINUX_DIR)/user_headers headers_install
+	grep '=[ym]' $(LINUX_DIR)/.config.set | LC_ALL=C sort | $(MKHASH) md5 > $(LINUX_DIR)/.vermagic
+endef
+
+define Kernel/Configure/Initramfs
+	$(call Kernel/SetInitramfs)
+endef
+
+define Kernel/CompileModules/Default
+	rm -f $(LINUX_DIR)/vmlinux $(LINUX_DIR)/System.map
+	+$(KERNEL_MAKE) $(if $(KERNELNAME),$(KERNELNAME),all) modules
+	# If .config did not change, use the previous timestamp to avoid package rebuilds
+	cmp -s $(LINUX_DIR)/.config $(LINUX_DIR)/.config.modules.save && \
+		mv $(LINUX_DIR)/.config.modules.save $(LINUX_DIR)/.config; \
+	$(CP) $(LINUX_DIR)/.config $(LINUX_DIR)/.config.modules.save
+endef
+
+OBJCOPY_STRIP = -R .reginfo -R .notes -R .note -R .comment -R .mdebug -R .note.gnu.build-id
+
+# AMD64 shares the location with x86
+ifeq ($(LINUX_KARCH),x86_64)
+IMAGES_DIR:=../../x86/boot
+endif
+
+define Kernel/CopyImage
+	cmp -s $(LINUX_DIR)/vmlinux $(KERNEL_BUILD_DIR)/vmlinux$(1).debug || { \
+		$(KERNEL_CROSS)objcopy -O binary $(OBJCOPY_STRIP) -S $(LINUX_DIR)/vmlinux $(LINUX_KERNEL)$(1); \
+		$(KERNEL_CROSS)objcopy $(OBJCOPY_STRIP) -S $(LINUX_DIR)/vmlinux $(KERNEL_BUILD_DIR)/vmlinux$(1).elf; \
+		$(CP) $(LINUX_DIR)/vmlinux $(KERNEL_BUILD_DIR)/vmlinux$(1).debug; \
+		$(foreach k, \
+			$(if $(KERNEL_IMAGES),$(KERNEL_IMAGES),$(filter-out vmlinux dtbs,$(KERNELNAME))), \
+			$(CP) $(LINUX_DIR)/arch/$(LINUX_KARCH)/boot/$(IMAGES_DIR)/$(k) $(KERNEL_BUILD_DIR)/$(k)$(1); \
+		) \
+	}
+endef
+
+# Always add "modules" so a proper Module.symvers file is written that
+# also contains symbols from the kernel modules. Without these symbols
+# external packages that depend on exported symbols from kernel modules
+# will fail to build.
+define Kernel/CompileImage/Default
+	rm -f $(TARGET_DIR)/init
+	+$(KERNEL_MAKE) $(KERNEL_MAKEOPTS_IMAGE) $(if $(KERNELNAME),$(KERNELNAME),all) modules
+	$(call Kernel/CopyImage)
+endef
+
+# Here as well, always add "modules", see comment above.
+ifneq ($(CONFIG_TARGET_ROOTFS_INITRAMFS),)
+define Kernel/CompileImage/Initramfs
+	$(call Kernel/Configure/Initramfs)
+	$(CP) $(GENERIC_PLATFORM_DIR)/other-files/init $(TARGET_DIR)/init
+	$(if $(SOURCE_DATE_EPOCH),touch -hcd "@$(SOURCE_DATE_EPOCH)" $(TARGET_DIR) $(TARGET_DIR)/init)
+	rm -rf $(KERNEL_BUILD_DIR)/linux-$(LINUX_VERSION)/usr/initramfs_data.cpio*
+ifeq ($(CONFIG_TARGET_ROOTFS_INITRAMFS_SEPARATE),y)
+ifneq ($(qstrip $(CONFIG_EXTERNAL_CPIO)),)
+	$(CP) $(CONFIG_EXTERNAL_CPIO) $(KERNEL_BUILD_DIR)/initrd.cpio
+else
+	( cd $(TARGET_DIR); find . | LC_ALL=C sort | $(STAGING_DIR_HOST)/bin/cpio --reproducible -o -H newc -R 0:0 > $(KERNEL_BUILD_DIR)/initrd.cpio )
+endif
+	$(if $(SOURCE_DATE_EPOCH),touch -hcd "@$(SOURCE_DATE_EPOCH)" $(KERNEL_BUILD_DIR)/initrd.cpio)
+	$(if $(CONFIG_TARGET_INITRAMFS_COMPRESSION_BZIP2),bzip2 -9 -c < $(KERNEL_BUILD_DIR)/initrd.cpio > $(KERNEL_BUILD_DIR)/initrd.cpio.bzip2)
+	$(if $(CONFIG_TARGET_INITRAMFS_COMPRESSION_GZIP),gzip -n -f -S .gzip -9n $(KERNEL_BUILD_DIR)/initrd.cpio)
+	$(if $(CONFIG_TARGET_INITRAMFS_COMPRESSION_LZMA),$(STAGING_DIR_HOST)/bin/lzma e -lc1 -lp2 -pb2 $(KERNEL_BUILD_DIR)/initrd.cpio $(KERNEL_BUILD_DIR)/initrd.cpio.lzma)
+# ?	$(if $(CONFIG_TARGET_INITRAMFS_COMPRESSION_LZO),)
+	$(if $(CONFIG_TARGET_INITRAMFS_COMPRESSION_XZ),$(STAGING_DIR_HOST)/bin/xz -T$(if $(filter 1,$(NPROC)),2,0) -9 -fz --check=crc32 $(KERNEL_BUILD_DIR)/initrd.cpio)
+# ?	$(if $(CONFIG_TARGET_INITRAMFS_COMPRESSION_LZ4),)
+	$(if $(CONFIG_TARGET_INITRAMFS_COMPRESSION_ZSTD),$(STAGING_DIR_HOST)/bin/zstd -T0 -f -o $(KERNEL_BUILD_DIR)/initrd.cpio.zstd $(KERNEL_BUILD_DIR)/initrd.cpio)
+endif
+	+$(KERNEL_MAKE) $(KERNEL_MAKEOPTS_IMAGE) $(if $(KERNELNAME),$(KERNELNAME),all) modules
+	$(call Kernel/CopyImage,-initramfs)
+endef
+else
+define Kernel/CompileImage/Initramfs
+endef
+endif
+
+define Kernel/Clean/Default
+	rm -f $(KERNEL_BUILD_DIR)/linux-$(LINUX_VERSION)/.configured
+	rm -f $(LINUX_KERNEL)
+	$(_SINGLE)$(MAKE) -C $(KERNEL_BUILD_DIR)/linux-$(LINUX_VERSION) clean
+endef