Creating a new distribution is not complicated, however we urge you to try existing distributions first, because it's also very easy to do wrong. The config need to be created in /conf/distro directory. So what has to be inside? DISTRO_VERSION so users will know which version of distribution they use. DISTRO_TYPE (release/debug) variable is used in some recipes to enable/disable some features - for example kernel output on screen for "debug" builds. Type of libc used: will it be glibc (TARGET_OS = "linux") or uclibc (TARGET_OS = "linux-uclibc")? Toolchain versions - for example gcc 3.4.4 based distro will have: PREFERRED_PROVIDERS += " virtual/${TARGET_PREFIX}gcc-initial:gcc-cross-initial" PREFERRED_PROVIDERS += " virtual/${TARGET_PREFIX}gcc:gcc-cross" PREFERRED_PROVIDERS += " virtual/${TARGET_PREFIX}g++:gcc-cross" PREFERRED_VERSION_binutils = "2.16" PREFERRED_VERSION_binutils-cross = "2.16" PREFERRED_VERSION_gcc = "3.4.4" PREFERRED_VERSION_gcc-cross = "3.4.4" PREFERRED_VERSION_gcc-initial-cross = "3.4.4" DISTRO_FEATURES which describe which features distro has. More about it in task-base section. Versions of kernels used for supported devices: PREFERRED_VERSION_linux-omap1_omap5912osk ?= "2.6.18+git" PREFERRED_VERSION_linux-openzaurus ?= "2.6.17" To get more stable build it is good to make use of sane-srcdates.inc file which contain working SRCDATE for many of floating recipes. require conf/distro/include/sane-srcdates.inc It also should have global SRCDATE value set (format is ISO date: YYYYMMDD): SRCDATE = "20061014"

To be able to build for device OpenEmbedded have to know it, so machine config file need to be written. All those configs are stored in /conf/machine/ directory. As usual some variables are required: TARGET_ARCH which describe which CPU architecture does machine use. MACHINE_FEATURES which describe which features device has. More about it in task-base section. PREFERRED_PROVIDER_virtual/kernel has to point into proper kernel recipe for this machine. Next kernel recipe needs to be added.

This section is a stub, help us by expanding it. Learn by example, go through the recipes that are already there and mimic them to do what you want.

Building against the latest, bleeding-edge source has some intricacies of its own. For one, it is desirable to pin down a souce code revision that is known to build to prevent random breakage in OE at the most inopportune time for all OE users. Here is how to do that properly. for svn: add 'PV = "1.1+svnr${SRCREV}"' to your bb file. for cvs: add 'PV = "1.1+cvs${SRCREV}"' to your bb file. Accompany either with an entry to conf/distro/include/sane-srcrevs.inc for a revision that you know builds successfully. If you really absolutely have to follow the latest commits, you can do that by adding 'SRCREV_pn-linux-davinci ?= ${AUTOREV}' to your local.conf, for example. In this case, you'd build against the most recent and unstable source for the pn-linux-davinci package.

Creating own image is easy - only few variables needs to be set: IMAGE_BASENAME to give a name for your own image PACKAGE_INSTALL to give a list of packages to install into the image RDEPENDS to give a list of recipes which are needed to be built to create this image IMAGE_LINGUAS is an optional list of languages which has to be installed into the image Then adding of the image class use: inherit image And the image recipe is ready for usage.

It might be necessary to integrate a prebuilt toolchain and other libraries but still be use OpenEmbedded to build packages. One of many approaches is shown and discussed here.

We assume the toolchain provides a C and C++ compiler, an assembler and other tools to build packages. The list below shows a gcc 3.4.4 toolchain for ARM architectures using glibc. We assume that the toolchain is in your PATH. ls pre-built/cross/bin arm-linux-g++ arm-linux-ld arm-linux-ranlib arm-linux-ar arm-linux-g77 arm-linux-readelf arm-linux-as arm-linux-gcc arm-linux-gcc-3.4.4 arm-linux-c++ arm-linux-size arm-linux-c++filt arm-linux-nm arm-linux-strings arm-linux-cpp arm-linux-objcopy arm-linux-strip arm-linux-objdump

We need the header files and the libraries itself. The following directory layout is assume. PRE_BUILT has two subdirectories one is called include and holds the header files and the other directory is called lib and holds the shared and static libraries. Additionally a Qt2 directory is present having a include and lib sub-directory. ls $PRE_BUILT include lib qt2

OpenEmbedded will be setup here. We assume that your machine and distribution is not part of OpenEmbedded and they will be created ad-hoc in the local.conf file. You will need to have BitBake and a current OpenEmbedded version available.

To ease the usage of OpenEmbedded we start by creating a source-able script. This is actually a small variation from the already seen script. We will name it build_source and you will need to source it. BITBAKE_PATH=/where/is/bitbake/bin TOOLCHAIN=/where/is/toolchain/bin HOST_TOOLS=/where/is/hosttools/bin export PRE_BUILT=/where/is/pre-built export PATH=$BITBAKE_PATH:$TOOLCHAIN:$HOST_TOOLS:$PATH export OEDIR=$PWD export LOCALDIR=$PWD/secret-isv Use source build_source to source the script, use env to check that the variable where exported.

We will configure OpenEmbedded now, it is very similar to what we have done above. DL_DIR = "${OEDIR}/sources" BBFILES := "${OEDIR}/openembedded/recipes/*/*.bb ${LOCALDIR}/recipes/*/*.bb" BBFILE_COLLECTIONS = "upstream local" BBFILE_PATTERN_upstream = "^${OEDIR}/openembedded/recipes/" BBFILE_PATTERN_local = "^${LOCALDIR}/recipes/" BBFILE_PRIORITY_upstream = "5" BBFILE_PRIORITY_local = "10" BBMASK = "" ${OEDIR}/openembedded will be a upstream release of OpenEmbedded. Above we have assumed it is in the current working directory. Additionally we have a ${LOCALDIR}, we combine these two directories as a special BitBake Collection. # # machine stuff # MACHINE = "secret-killer" PACKAGE_EXTRA_ARCHS = "armv4 armv4t armv5te iwmmxt xscale"" TARGET_CC_ARCH = "-mcpu=xscale -mtune=iwmmxt" TARGET_ARCH = "arm" PACKAGE_ARCH="xscale" We tell OpenEmbedded that we build for the ARM platform and optimize for xscale and iwmmxt. INHERIT += " package_ipk debian" TARGET_OS = "linux" TARGET_FPU = "soft" DISTRO = "secret-disro" DISTRO_NAME = "secret-distro" DISTRO_VERSION = "x.y.z" DISTRO_TYPE = "release" Create a distribution ad-hoc as well. We tell OpenEmbedded that we build for linux and glibc using soft float as fpu. If your toolchain is a uclibc toolchain you will need to set TARGET_OS to linux-uclibc. export CC="${CCACHE}arm-linux-gcc-3.4.4 ${HOST_CC_ARCH}" export CXX="${CCACHE}arm-linux-g++ ${HOST_CC_ARCH}" export CPP="arm-linux-gcc-3.4.4 -E" export LD="arm-linux-ld" export AR="arm-linux-ar" export AS="arm-linux-as" export RANLIB="arm-linux-ranlib" export STRIP="arm-linux-strip" The above variables replace the ones from bitbake.conf. This will make OpenEmbedded use the prebuilt toolchain. # # point OE to the lib and include directory # TARGET_CPPFLAGS_append = " -I${PRE_BUILT}/include " TARGET_LDFLAGS_prepend = " -L${PRE_BUILT}/qt2/lib -L${PRE_BUILT}/lib \ -Wl,-rpath-link,${PRE_BUILT}/lib -Wl,-rpath-link,${PRE_BUILT}/qt2/lib " # special to Qt/Qtopia QTDIR = "${PRE_BUILT}/qt2" QPEDIR = "${PRE_BUILT}" palmtopdir = "/opt/Qtopia" palmqtdir = "/opt/Qtopia" We will add the PRE_BUILT libraries to the include and library paths. And the same is done for the special version of Qt we have in your PRE_BUILT directory. ASSUME_PROVIDED += " virtual/${TARGET_PREFIX}gcc " ASSUME_PROVIDED += " virtual/libc " ASSUME_PROVIDED += " virtual/qte " ASSUME_PROVIDED += " virtual/libqpe " ASSUME_PROVIDED += " libqpe-opie " Now we have told BitBake that the C library, compiler and Qtopia is already provided. These lines will avoid building binutils, gcc initial, glibc, gcc. source build_source bitbake your-killer-app You should be able to create the packages you want to using the prebuilt toolchain now.

If you have more prebuilt libraries you need to add additional ASSUME_PROVIDED lines to your local.conf. Using bitbake -vvv PACKAGE you can easily see the package names you could ASSUME_PROVIDED if you have some prebuilt.

NOTE: Couldn't find shared library provider for libqtopia.so.1 NOTE: Couldn't find shared library provider for libqtopia2.so.2 NOTE: Couldn't find shared library provider for libqpe.so.1 NOTE: Couldn't find shared library provider for libpthread.so.0 NOTE: Couldn't find shared library provider for libstdc++.so.6 NOTE: Couldn't find shared library provider for libqte.so.2 NOTE: Couldn't find shared library provider for libgcc_s.so.1 NOTE: Couldn't find shared library provider for libc.so.6 NOTE: Couldn't find shared library provider for libm.so.6 OpenEmbedded tries to automatically add run-time dependencies (RDEPENDS) to the package. It uses the shlibs system to do add them, in this case it was not able to find packages providing these libraries as they are prebuilt. This means they will not be added to the RDEPENDS of the just created package. The result can be fatal. If you use OpenEmbedded to create images you will end up with a image without a libc being installed. This will lead to a fatal failure. To workaround this issue you could create a package for the metadata to install every needed library and use ${BOOTSTRAP_EXTRA_RDEPENDS} to make sure this package is installed when creating images. However, the correct way to resolve this is to provide explicit mapping using ASSUME_SHLIBS variable. For example, for the libraries above (partial): ASSUME_SHLIBS = "libqtopia2.so.2:qtopia2_2.4 libc.so.6:libc" The format is shlib_file_name:package[_version]. If a version is specified it will be used as the minimal (>=) version for the dependency.

This section is a stub, help us by expanding it