Preparing to Use the Application Development Toolkit (ADT) 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 how to be sure you meet the ADT requirements.
Installing the ADT 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 build the cross-toolchain within 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.
Using the ADT Installer To run the ADT Installer, you need to first get the ADT Installer tarball and then run the ADT Installer Script.
Getting the ADT Installer Tarball 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 (oe-init-build-env) 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
Configuring and Running the ADT Installer Script 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/$SDKVERSION, and image tarballs in the adt-installer directory according to your installer configurations, and the target sysroot located according to the YOCTOADT_TARGET_SYSROOT_LOC_<arch> variable also in your configuration file.
Using a Cross-Toolchain Tarball If you want to simply install the cross-toolchain by hand, you can do so by using an existing cross-toolchain tarball. If you use this method to install the cross-toolchain and you still need to install the target sysroot, you will have to install sysroot separately. Follow these steps: Go to and find the folder that matches your host development system (i.e. i586 for 32-bit machines or x86_64 for 64-bit machines). Go into that folder and download the toolchain tarball whose name includes the appropriate target architecture. For example, if your host development system is an Intel-based 64-bit system and you are going to use your cross-toolchain for an Intel-based 32-bit target, go into the x86_64 folder and download the following tarball: yocto-eglibc-x86_64-i586-toolchain-gmae-1.1.tar.bz2 The cross-toolchain tarballs provided by the Yocto Project support development of GNOME platforms on mobile devices (GMAE). As an alternative to steps one and two, you can build the toolchain tarball if you have a Yocto Project build tree. If you need GMAE, you should use the bitbake meta-toolchain-gmae command. The resulting tarball will support such development. However, if you are not concerned with GMAE, you can generate the tarball using bitbake meta-toolchain. Use the appropriate bitbake command only after you have sourced the oe-build-init-env script located in the Yocto Project files. When the bitbake command completes, the tarball will be in tmp/deploy/sdk in the Yocto Project build tree. Make sure you are in the root directory with root privileges and then expand the tarball. The tarball expands into /opt/poky/$SDKVERSION. Once the tarball is expanded, the cross-toolchain is installed. You will notice environment setup files for the cross-toolchain in the directory.
Using BitBake and the Yocto Project Build Tree A final way of installing just the cross-toolchain is to use BitBake to build the toolchain within an existing Yocto Project build tree. This method does not install the toolchain into the /opt directory. As with the previous method, if you need to install the target sysroot, you must do this separately. Follow these steps to build and install the toolchain into the build tree: Source the environment setup script oe-init-build-env located in the Yocto Project files. 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 change out of your working directory after you source the environment setup script and before you run the BitBake command, the command might not work. Be sure to run the bitbake command immediately after checking or editing the local.conf but without changing out of your working directory. Once BitBake finishes, the cross-toolchain is installed within the Yocto Project build tree. 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.
Setting Up the Cross-Development Environment Before you can develop using the cross-toolchain, you need to set up the cross-development 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 installed the toolchain in the build tree, you can find the environment setup scripts in the Yocto Project build tree's 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
Securing Kernel and Filesystem Images You will need to have a kernel and filesystem image to boot using your hardware or the QEMU emulator. Furthermore, if you plan on booting your image using NFS or you want to use the root filesystem as the target sysroot, you need to extract the root filesystem.
Getting the Images To get the kernel and filesystem images, you either have to build them or download pre-built versions. You can find examples for both these situations in the "A Quick Test Run" section of The Yocto Project Quick Start. The Yocto Project provides basic kernel and filesystem images for several architectures (x86, x86-64, mips, powerpc, and arm) that you can use unaltered in the QEMU emulator. These kernel images reside in the Yocto Project release area - and are ideal for experimentation within Yocto Project. If you plan on remotely deploying and debugging your application from within the Eclipse IDE, you must have an image that contains the Yocto Target Communication Framework (TCF) agent (tcf-agent), which is the core-image-sato-sdk image. For information on the image types you can build using the Yocto Project, see Reference: Images in The Yocto Project Reference Manual.
Extracting the Root Filesystem You must extract the root filesystem if you want to boot the image using NFS or you want to use the root filesystem as the target sysroot. For example, the Eclipse IDE environment with the Eclipse Yocto Plug-in installed allows you to use QEMU to boot under NFS. Another example is if you want to develop your target application using the root filesystem as the target sysroot. To extract the root filesystem, first source the cross-development environment setup script and then use the runqemu-extract-sdk command on the filesystem image. For example, the following commands set up the environment and then extract the root filesystem from a previously built filesystem image tarball named core-image-sato-sdk-qemux86-2011091411831.rootfs.tar.bz2. The example extracts the root filesystem into the $HOME/qemux86-sato directory: $ source $HOME/poky/build/tmp/environment-setup-i586-poky-linux $ runqemu-extract-sdk \ tmp/deploy/images/core-image-sato-sdk-qemux86-2011091411831.rootfs.tar.bz2 \ $HOME/qemux86-sato In this case, you could now point to the target sysroot at $HOME/qemux86-sato.