diff --git a/generic-dts/Makefile b/generic-dts/Makefile
index 1408422..82cd58c 100644
--- a/generic-dts/Makefile
+++ b/generic-dts/Makefile
@@ -15,6 +15,13 @@ DTC_CPP_FLAGS += $(EXTRA_CPP_FLAGS)
 
 DTC_CPP_FLAGS += -DLINUX_VERSION=600 -DTEGRA_HOST1X_DT_VERSION=2
 
+ifneq ($(findstring ack_src,$(NV_BUILD_KERNEL_OPTIONS)),)
+ifneq ($(TOP),)
+SOURCE_TOP := $(TOP)
+else
+$(error TOP is not defined)
+endif
+else
 ifneq ($(TEGRA_TOP),)
 SOURCE_TOP := $(TEGRA_TOP)
 else ifneq ($(TOP),)
@@ -22,6 +29,7 @@ SOURCE_TOP := $(TOP)
 else
 $(error TEGRA_TOP or TOP is not defined)
 endif
+endif
 
 tegra-dtstree := $(SOURCE_TOP)/hardware/nvidia
 
diff --git a/legacy-dts/Makefile b/legacy-dts/Makefile
index 5d28af9..a458475 100644
--- a/legacy-dts/Makefile
+++ b/legacy-dts/Makefile
@@ -19,6 +19,13 @@ DTC_CPP_FLAGS += $(EXTRA_CPP_FLAGS)
 
 DTC_CPP_FLAGS += -DLINUX_VERSION=600 -DTEGRA_HOST1X_DT_VERSION=2
 
+ifneq ($(findstring ack_src,$(NV_BUILD_KERNEL_OPTIONS)),)
+ifneq ($(TOP),)
+SOURCE_TOP := $(TOP)
+else
+$(error TOP is not defined)
+endif
+else
 ifneq ($(TEGRA_TOP),)
 SOURCE_TOP := $(TEGRA_TOP)
 else ifneq ($(TOP),)
@@ -26,6 +33,7 @@ SOURCE_TOP := $(TOP)
 else
 $(error TEGRA_TOP or TOP is not defined)
 endif
+endif
 
 tegra-dtstree := $(SOURCE_TOP)/hardware/nvidia
 # Get relative path for tegra-dtstree from this makefile