The GPL source is created for ASUS wireless router related products. Please visit the ASUS support site (http://support.asus.com) to get the latest GPL tarball.It has a lot in common with many wireless router open source projects, including Oleg/Tomato/DD-WRT/OpenWRT. Thanks the developers of those projects for making the source code available.

Set Up Environment(Tested in Fedora 8/9 and Ubuntu)

    1. prepare environment
	
	a. Ubuntu
		Install these packages (I used synaptic: "sudo synaptic")

		libncurses5
		libncurses5-dev
		m4
		bison
		gawk
		flex
		libstdc++6-4.4-dev
		g++-4.4
		g++
		gengetopt
		git (or git-core)
		gitk
		zlib1g-dev
		autoconf
		autopoint (or gettext)
		libtool
		shtool
		autogen
		mtd-utils
		intltool
		sharutils
		docbook-xsl-*
		libstdc++5
		texinfo
		dos2unix (or tofrodos)
		xsltproc
		uboot-mkimage
		device-tree-compiler
		python 2.7 or above.

		If you are using Ubuntu amd64, you may need to install 32-bit packages listed below.
			libc6-i386
			lib32stdc++6
			lib32z1

		If you are using Ubuntu amd64, you may need to install 32-bit packages listed below.
			libc6-i386
			lib32stdc++6
			lib32z1

	b. Fedora
		python 2.7 or above.
		sudo yum groupinstall "Development Tools"
		sudo yum install gettext-devel libxml2-devel mtd-utils-ubi ncurses-devel \
			zlib-devel intltool sharutils docbook-dtds docbook-style-xsl \
			uboot-tools dtc gengetopt

		If you are using Fedora 19 or above, you need to install below packages.
		sudo yum groupinstall "C Development Tools and Libraries"

		If you are using Fedora x86_64, you may need to install 32-bit packages listed below.
			glibc.i686
			libstdc++.i686
			zlib.i686
   
   2. prepare source to, ex, $HOME/asuswrt

	cd $HOME
	tar xvfz [tar file]
 
   3. setup development system

	Broadcom SoC models
	===================

		To install the tools:
	    	    - copy the tools/brcm/ directory to /opt
		    - add /opt/brcm/hndtools-mipsel-linux/bin to your path
		    - add /opt/brcm/hndtools-mipsel-uclibc/bin to your path

	Mediatek/Ralink SoC models
	==========================

		To install the tools:
	    	    - copy the tools/brcm/ directory to /opt
		    - add /opt/brcm/hndtools-mipsel-linux/bin to your path
		    - add /opt/brcm/hndtools-mipsel-uclibc/bin to your path
	    	    - extract tools/buildroot-gcc342.tar.bz2 to /opt
		    - add /opt/buildroot-gcc342/bin to your path

		For MT7621 Uboot:
	    	    - extract mips-2012.03.tar.bz2 directory to /opt
		    - add /opt/mips-2012.03/bin to your uboot path

	Qualcomm QCA9557 MIPS SoC models
	================================

		For example, RT-AC55U, 4G-AC55U.

		To install the tools:
	    	    - extract tools/openwrt-gcc463.mips.tar.bz2 directory to /opt
		    - add /opt/openwrt-gcc463.mips/bin to your path
		    - If you want to build small utilities out of asuswrt box,
		      add STAGING_DIR environment variable as below:

		      export STAGING_DIR=/opt/openwrt-gcc463.mips

	Qualcomm IPQ806x/IPQ40xx ARM SoC models
	===============================

		For example, BRT-AC828.

		To install the tools:
		    - extract tools/openwrt-gcc463.arm.tar.bz2 directory to /opt
		    - add /opt/openwrt-gcc463.arm/bin to your path
		    - If you want to build small utilities out of asuswrt box,
		      add STAGING_DIR environment variable as below:
	
		      export STAGING_DIR=/opt/openwrt-gcc463.arm

	Note: Broadcom/Ralink(except 4708 series) platform use the same toolchain for user space program, so please set PATH to the same directory as above
   
   4. build firmware.

	a. rt-n16
		cd release/src-rt
		make rt-n16

	b. rt-n56u
		cd release/src-ra
		make rt-n56u

	c. rt-n65u
		cd release/src-ra-3.0
		make rt-n65u
	
	d. rt-n14u (/ rt-ac52u / rt-ac51u / rt-n11p / rt-n54u)
		cd release/src-ra-mt7620
		make rt-n14u
		( make rt-ac52u  )
		( make rt-ac51u  )
		( make rt-n11p   )
		( make rt-n54u   )

	e. rt-ac56u (/ rt-ac68u / rt-n18uhp)
		cd release/src-rt-6.x.4708
		make rt-ac56u
		( make rt-ac68u  )
		( make rt-n18uhp )

	f. rt-ac55u (/ rt-ac55uhp )
		cd release/src-qca
		make rt-ac55u
		( make rt-ac55uhp )

	g. brt-ac828 (/ rt-ac88q )
		cd release/src-qca-ipq8064
		make brt-ac828

	h. rt-ac58u (/ rt-ac42u )
		cd release/src-qca-dakota
		make rt-ac58u
		( make rt-ac42u )