In order to use the ADT, you must install it, source a script to set up the environment, and be sure both the kernel and filesystem image specific to the target architecture exist. This chapter describes two important terms and how to be sure you meet the ADT requirements.

Before learning how to prepare your system for the ADT, you need to understand two important terms used throughout this manual: The Yocto Project Files: This term refers to the directory structure created as a result of downloading and unpacking a Yocto Project release tarball or setting up a Git repository by cloning git://git.yoctoproject.org/poky. The Yocto Project files contain BitBake, Documentation, metadata and other files that all support the development environment. Consequently, you must have the Yocto Project files in place on your development system in order to do any development using the Yocto Project. The name of the top-level directory of the Yocto Project file structure is derived from the Yocto Project release tarball. For example, downloading and unpacking poky-edison-6.0.tar.bz2 results in a Yocto Project source tree whose Yocto Project source directory is named poky-edison-6.0. If you create a Git repository, then you can name the repository anything you like. You can find instruction on how to set up the Yocto Project files on your host development system by reading the Getting Setup section in The Yocto Project Development Manual. Yocto Project Build Tree: This term refers to the area where the Yocto Project builds images. The area is created when you source the Yocto Project setup environment script that is found in the Yocto Project files area. (e.g. oe-init-build-env). You can create the Yocto Project build tree anywhere you want on your development system. Here is an example that creates the tree in mybuilds and names the Yocto Project build directory YP-6.0: $ source poky-edison-6.0/oe-init-build-env $HOME/mybuilds/YP-6.0 If you don't specifically name the build directory, then BitBake creates it in the current directory and uses the name build. Also, if you supply an existing directory, then BitBake uses that directory as the Yocto Project build directory and populates the build tree beneath it.

The following list describes how you can install the ADT, which includes the cross-toolchain. Regardless of the installation you choose, you must source the cross-toolchain environment setup script before you use the toolchain. See the "Setting Up the Environment" section for more information. Use the ADT Installer Script: This method is the recommended way to install the ADT because it automates much of the process for you. For example, you can configure the installation to install the QEMU emulator and the user-space NFS, specify which root filesystem profiles to download, and define the target sysroot location. Use an Existing Toolchain Tarball: Using this method, you select and download an architecture-specific toolchain tarball and then hand-install the toolchain. If you use this method, you just get the cross-toolchain and QEMU - you do not get any of the other mentioned benefits had you run the ADT Installer script. Use the Toolchain from within a Yocto Project Build Tree: If you already have a Yocto Project build tree, you can install the cross-toolchain using that tree. However, like the previous method mentioned, you only get the cross-toolchain and QEMU - you do not get any of the other benefits without taking separate steps.

To run the ADT Installer, you need to first get the ADT Installer tarball and then run the ADT Installer Script.

The ADT Installer is contained in the ADT Installer tarball. You can download the tarball into any directory from . Or, you can use BitBake to generate the tarball inside the existing Yocto Project build tree. If you use BitBake to generate the ADT Installer tarball, you must source the Yocto Project environment setup script located in the Yocto Project file structure before running the bitbake command that creates the tarball. The following example commands download the Yocto Project release tarball, set up the Yocto Project files structure, set up the environment while also creating the default Yocto Project build tree, and run the bitbake command that results in the tarball ~/yocto-project/build/tmp/deploy/sdk/adt_installer.tar.bz2: $ cd ~ $ mkdir yocto-project $ cd yocto-project $ wget http://www.yoctoproject.org/downloads/poky/poky-edison-6.0.tar.bz2 $ tar xjf poky-edison-6.0.tar.bz2 $ source poky-edison-6.0/oe-init-build-env $ bitbake adt-installer

Before running the ADT Installer script, you need to unpack the tarball. You can unpack the tarball in any directory you wish. Unpacking it creates the directory adt-installer, which contains the ADT Installer script (adt_installer) and its configuration file (adt_installer.conf). Before you run the script, however, you should examine the ADT Installer configuration file and be sure you are going to get what you want. Your configurations determine which kernel and filesystem image are downloaded. The following list describes the configurations you can define for the ADT Installer. For configuration values and restrictions, see the comments in the adt-installer.conf file: YOCTOADT_REPO: This area includes the IPKG-based packages and the root filesystem upon which the installation is based. If you want to set up your own IPKG repository pointed to by YOCTOADT_REPO, you need to be sure that the directory structure follows the same layout as the reference directory set up at . Also, your repository needs to be accessible through HTTP. YOCTOADT_TARGETS: The machine target architectures for which you want to set up cross-development environments. YOCTOADT_QEMU: Indicates whether or not to install the emulator QEMU. YOCTOADT_NFS_UTIL: Indicates whether or not to install user-mode NFS. If you plan to use the Yocto Eclipse IDE plug-in against QEMU, you should install NFS. To boot QEMU images using our userspace NFS server, you need to be running portmap or rpcbind. If you are running rpcbind, you will also need to add the -i option when rpcbind starts up. Please make sure you understand the security implications of doing this. You might also have to modify your firewall settings to allow NFS booting to work. YOCTOADT_ROOTFS_<arch>: The root filesystem images you want to download from the YOCTOADT_IPKG_REPO repository. YOCTOADT_TARGET_SYSROOT_IMAGE_<arch>: The particular root filesystem used to extract and create the target sysroot. The value of this variable must have been specified with YOCTOADT_ROOTFS_<arch>. For example, if you downloaded both minimal and sato-sdk images by setting YOCTOADT_ROOTFS_<arch> to "minimal sato-sdk", then YOCTOADT_ROOTFS_<arch> must be set to either minimal or sato-sdk. YOCTOADT_TARGET_SYSROOT_LOC_<arch>: The location on the development host where the target sysroot is created. After you have configured the adt_installer.conf file, run the installer using the following command: $ adt_installer The ADT Installer requires the libtool package to complete. If you install the recommended packages as described in the Packages section of The Yocto Project Quick Start, then you will have libtool installed. Once the installer begins to run, you are asked whether you want to run in interactive or silent mode. If you want to closely monitor the installation, choose “I” for interactive mode rather than “S” for silent mode. Follow the prompts from the script to complete the installation. Once the installation completes, the ADT, which includes the cross-toolchain, is installed. You will notice environment setup files for the cross-toolchain in /opt/poky/$SDKVERSION, and image tarballs in the adt-installer directory according to your installer configurations, and the target sysroot located according to the YOCTOADT_TARGET_SYSROOT_LOC_<arch> variable also in your configuration file.

If you want to simply install the cross-toolchain by hand, you can do so by using an existing cross-toolchain tarball. If you install the cross-toolchain by hand, you will have to set up the target sysroot separately. Follow these steps: Go to and find the folder that matches your host development system (i.e. i686 for 32-bit machines or x86_64 for 64-bit machines). Go into that folder and download the toolchain tarball whose name includes the appropriate target architecture. For example, if your host development system is an Intel-based 64-bit system and you are going to use your cross-toolchain for an ARM-based target, go into the x86_64 folder and download the following tarball: yocto-eglibc-x86_64-arm-toolchain-gmae-1.1.tar.bz2 As an alternative to steps one and two, you can build the toolchain tarball if you have a Yocto Project build tree. Use the bitbake meta-toolchain command after you have sourced the oe-build-init script located in the Yocto Project files. When the bitbake command completes, the toolchain tarball will be in tmp/deploy/sdk in the Yocto Project build tree. Make sure you are in the root directory with root privileges and then expand the tarball. The tarball expands into /opt/poky/$SDKVERSION. Once the tarball in unpacked, the cross-toolchain is installed. You will notice environment setup files for the cross-toolchain in the directory.

A final way of installing just the cross-toolchain is to use BitBake within an existing Yocto Project build tree. Follow these steps: Source the environment setup script located in the Yocto Project files. The script has the string init-build-env as part of the name. At this point, you should be sure that the MACHINE variable in the local.conf file found in the Yocto Project file structure's conf directory is set for the target architecture. Comments within the local.conf file list the values you can use for the MACHINE variable. You can populate the build tree with the cross-toolchains for more than a single architecture. You just need to edit the MACHINE variable in the local.conf file and re-run the BitBake command. Run bitbake meta-ide-support to complete the cross-toolchain installation. If you change your working directory after you source the environment setup script and before you run the BitBake command, the command will not work. Be sure to run the bitbake command immediately after checking or editing the local.conf but without changing your working directory. Once BitBake finishes, the cross-toolchain is installed. You will notice environment setup files for the cross-toolchain in the Yocto Project build tree in the tmp directory. Setup script filenames contain the strings environment-setup.

Before you can use the cross-toolchain, you need to set up the toolchain environment by sourcing the environment setup script. If you used the ADT Installer or used an existing ADT tarball to install the ADT, then you can find this script in the /opt/poky/$SDKVERSION directory. If you used BitBake and the Yocto Project Build Tree to install the cross-toolchain, then you can find the environment setup scripts in in the Yocto Project build tree in the tmp directory. Be sure to run the environment setup script that matches the architecture for which you are developing. Environment setup scripts begin with the string “environment-setup” and include as part of their name the architecture. For example, the environment setup script for a 64-bit IA-based architecture would be the following: /opt/poky/1.1/environment-setup-x86_64-poky-linux

You will need to have a kernel and filesystem image to boot using your hardware or the QEMU emulator. That means you either have to build them or know where to get them. You can find lots of details on how to get or build images and kernels for your architecture in The Yocto Project Quick Start. The Yocto Project provides basic kernels and filesystem images for several architectures (x86, x86-64, mips, powerpc, and arm) that you can use unaltered in the QEMU emulator. These kernels and filesystem images reside in the Yocto Project release area - and are ideal for experimentation within Yocto Project.