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+################################################################################
+
+1. How to Build
+	- get Toolchain
+		From android git server , codesourcery and etc ..
+		 - arm-linux-androideabi-4.9
+		
+	- edit Makefile
+		edit "CROSS_COMPILE" to right toolchain path(You downloaded).
+		  EX)  CROSS_COMPILE= $(android platform directory you download)/android/prebuilts/gcc/linux-x86/arm/arm-linux-androideabi-4.9/bin/arm-linux-androideabi-
+		  Ex)  CROSS_COMPILE=/usr/local/toolchain/arm-linux-androideabi-4.9/bin/arm-linux-androideabi-		// check the location of toolchain
+  	
+        - to Build
+          $ make ARCH=arm64 exynos7570-on5xelte_mea_defconfig
+          $ make ARCH=arm64
+
+2. Output files
+	- Kernel : arch/arm/boot/zImage
+	- module : drivers/*/*.ko
+
+3. How to Clean	
+		$ make clean
+		
+################################################################################