diff --git a/board/avionic-design/medcom-wide/Makefile b/board/avionic-design/medcom-wide/Makefile
index 3077319..6c4ab64 100644
--- a/board/avionic-design/medcom-wide/Makefile
+++ b/board/avionic-design/medcom-wide/Makefile
@@ -7,28 +7,8 @@
 # SPDX-License-Identifier:	GPL-2.0+
 #
 
-include $(TOPDIR)/config.mk
-
 $(shell mkdir -p $(obj)../common $(obj)../../nvidia/common)
 
-LIB	= $(obj)lib$(BOARD).o
-
-COBJS-y	:= ../common/tamonten.o
+obj-y	:= ../common/tamonten.o
 
 include ../../nvidia/common/common.mk
-
-COBJS	:= $(COBJS-y)
-SRCS	:= $(COBJS:.o=.c)
-OBJS	:= $(addprefix $(obj),$(COBJS))
-
-$(LIB):	$(obj).depend $(OBJS)
-	$(call cmd_link_o_target, $(OBJS))
-
-#########################################################################
-
-# defines $(obj).depend target
-include $(SRCTREE)/rules.mk
-
-sinclude $(obj).depend
-
-#########################################################################
diff --git a/board/avionic-design/plutux/Makefile b/board/avionic-design/plutux/Makefile
index 3077319..6c4ab64 100644
--- a/board/avionic-design/plutux/Makefile
+++ b/board/avionic-design/plutux/Makefile
@@ -7,28 +7,8 @@
 # SPDX-License-Identifier:	GPL-2.0+
 #
 
-include $(TOPDIR)/config.mk
-
 $(shell mkdir -p $(obj)../common $(obj)../../nvidia/common)
 
-LIB	= $(obj)lib$(BOARD).o
-
-COBJS-y	:= ../common/tamonten.o
+obj-y	:= ../common/tamonten.o
 
 include ../../nvidia/common/common.mk
-
-COBJS	:= $(COBJS-y)
-SRCS	:= $(COBJS:.o=.c)
-OBJS	:= $(addprefix $(obj),$(COBJS))
-
-$(LIB):	$(obj).depend $(OBJS)
-	$(call cmd_link_o_target, $(OBJS))
-
-#########################################################################
-
-# defines $(obj).depend target
-include $(SRCTREE)/rules.mk
-
-sinclude $(obj).depend
-
-#########################################################################
diff --git a/board/avionic-design/tec/Makefile b/board/avionic-design/tec/Makefile
index 3077319..6c4ab64 100644
--- a/board/avionic-design/tec/Makefile
+++ b/board/avionic-design/tec/Makefile
@@ -7,28 +7,8 @@
 # SPDX-License-Identifier:	GPL-2.0+
 #
 
-include $(TOPDIR)/config.mk
-
 $(shell mkdir -p $(obj)../common $(obj)../../nvidia/common)
 
-LIB	= $(obj)lib$(BOARD).o
-
-COBJS-y	:= ../common/tamonten.o
+obj-y	:= ../common/tamonten.o
 
 include ../../nvidia/common/common.mk
-
-COBJS	:= $(COBJS-y)
-SRCS	:= $(COBJS:.o=.c)
-OBJS	:= $(addprefix $(obj),$(COBJS))
-
-$(LIB):	$(obj).depend $(OBJS)
-	$(call cmd_link_o_target, $(OBJS))
-
-#########################################################################
-
-# defines $(obj).depend target
-include $(SRCTREE)/rules.mk
-
-sinclude $(obj).depend
-
-#########################################################################