diff --git a/config/BoardConfigKernel.mk b/config/BoardConfigKernel.mk
index cee3463..e7d245d 100644
--- a/config/BoardConfigKernel.mk
+++ b/config/BoardConfigKernel.mk
@@ -27,6 +27,9 @@
 #                                                      x86_64-linux-android- for x86
 #
 #   TARGET_KERNEL_CLANG_COMPILE        = Compile kernel with clang, defaults to true
+#   TARGET_KERNEL_VERSION              = Reported kernel version in top level kernel
+#                                        makefile. Can be overriden in device trees
+#                                        in the event of prebuilt kernel.
 #
 #   KERNEL_TOOLCHAIN_PREFIX            = Overrides TARGET_KERNEL_CROSS_COMPILE_PREFIX,
 #                                          Set this var in shell to override
@@ -48,6 +51,10 @@
 KERNEL_ARCH := $(TARGET_KERNEL_ARCH)
 endif
 
+KERNEL_VERSION := $(shell grep "^VERSION = " $(TARGET_KERNEL_SOURCE)/Makefile | awk '{ print $$3 }')
+KERNEL_PATCHLEVEL := $(shell grep "^PATCHLEVEL = " $(TARGET_KERNEL_SOURCE)/Makefile | awk '{ print $$3 }')
+TARGET_KERNEL_VERSION ?= $(shell echo $(KERNEL_VERSION)"."$(KERNEL_PATCHLEVEL))
+
 CLANG_PREBUILTS := $(BUILD_TOP)/prebuilts/clang/host/$(HOST_PREBUILT_TAG)/clang-r450784d
 GCC_PREBUILTS := $(BUILD_TOP)/prebuilts/gcc/$(HOST_PREBUILT_TAG)
 # arm64 toolchain
@@ -146,6 +153,13 @@
 KERNEL_MAKE_FLAGS += HOSTCC=$(CLANG_PREBUILTS)/bin/clang
 KERNEL_MAKE_FLAGS += HOSTCXX=$(CLANG_PREBUILTS)/bin/clang++
 
+# Use LLVM's substitutes for GNU binutils if compatible kernel version.
+ifneq ($(TARGET_KERNEL_CLANG_COMPILE), false)
+ifneq (,$(filter 5.4, $(TARGET_KERNEL_VERSION)))
+    KERNEL_MAKE_FLAGS += LLVM=1 LLVM_IAS=1
+endif
+endif
+
 # Since Linux 4.16, flex and bison are required
 KERNEL_MAKE_FLAGS += LEX=$(BUILD_TOP)/prebuilts/build-tools/$(HOST_PREBUILT_TAG)/bin/flex
 KERNEL_MAKE_FLAGS += YACC=$(BUILD_TOP)/prebuilts/build-tools/$(HOST_PREBUILT_TAG)/bin/bison