Last year I upstreamed support for the Galileo Gen 1/2 to the Yocto project. So before I go any further detail talking about building a homebrew LTE modem based on the Galileo, I need to first describe the steps building a configurable Linux distro for the Intel Galileo 1/2.

First off - a quick explaination. Yocto is the umbrella for a number of seperate projects Bitbake, Poky, OpenEmbedded and various BSPs.

  • Bitbake is the build tool - the tool that interprets recipes, figures how to build a given package, it’s dependences, it’s ordering relative to other packages.
  • Openembedded - provides the recipes and support scripts required to build Linux.
  • Poky - aggregate’s Bitbake and Openembedded, with policy to build a reference Linux distribution.

Finally before we build, the most recent version of Yocto is 2.1 ‘korgoth’. You will see me reference krogoth below.

Quick tutorial for building Yocto the Intel Galileo.

  1. Clone Poky and checkout krogoth.

     # git clone
     # git checkout -b krogoth origin/krogoth
  2. Add meta-intel - the BSP for Intel Boards and checkout krogoth.

     # git clone
     # git checkout -b krogoth origin/korgoth
  3. Setup the yocto environment, source the open embedded script. This will automagically change your directory to poky/yocto_build.

     # cd poky 
     # . oe-init-build-env yocto_build/
  4. Add the meta-intel BSP as a layer.

     # bitbake-layers add-layer ../../meta-intel
     # bitbake-layers show-layers
     layer                 path                                      priority
     meta                  /build/yocto/openembedded-core/meta       5
     meta-intel            /build/yocto/meta-intel                   5
     meta-oe               /build/yocto/meta-openembedded/meta-oe    6
  5. Edit your local.conf, and change your machine type to “intel-quark”.

     # vi conf/local.conf
     # Machine Selection
     # You need to select a specific machine to target the build with. There are a selection
     # of emulated machines available which can boot and run in the QEMU emulator:
     #MACHINE ?= "qemuarm"
     #MACHINE ?= "qemuarm64"
     #MACHINE ?= "qemumips"
     #MACHINE ?= "qemumips64"
     #MACHINE ?= "qemuppc"
     #MACHINE ?= "qemux86"
     #MACHINE ?= "qemux86-64"
     # This sets the default machine to be qemux86 if no other machine is selected:
     #MACHINE ??= "qemux86"
     MACHINE ?= "intel-quark"
  6. Build Yocto, I usually build Poky’s minimal image - core-image-minimal.

     # bitbake core-image-minimal 
     ... wait around 30 minutes ...
  7. Use the mkgalileodisk wic configuration to create a disk image suitable to burn to an sdcard.

     # wic create mkgalileodisk -e core-image-minimal 
     Checking basic build environment...
     Creating image(s)...
     Info: The new image(s) can be found here:
     The following build artifacts were used to create the image(s):
       ROOTFS_DIR:                   /build/yocto/openembedded-core/yocto_build/tmp-glibc/work/intel_quark-oe-linux/core-image-minimal/1.0-r0/rootfs
       BOOTIMG_DIR:                  /build/yocto/openembedded-core/yocto_build/tmp-glibc/work/intel_quark-oe-linux/core-image-minimal/1.0-r0/core-image-minimal-1.0/hddimg
       KERNEL_DIR:                   /build/yocto/openembedded-core/yocto_build/tmp-glibc/deploy/images/intel-quark
       NATIVE_SYSROOT:               /build/yocto/openembedded-core/yocto_build/tmp-glibc/sysroots/x86_64-linux
     The image(s) were created using OE kickstart file:
  8. You can now burn the image to an SD Card using your tool of choice. I prefer dd on Linux and Win32 Disk Imager on Windows