Table of Contents

Setup a Cross-Compile Environment for Drobo

The first step in cross-compiling software is to get a working environment that you can use for it. I am setting up my environment to cross compile for the Drobo FS using the latest Ubuntu Lucid and used this article Building MediaTomb for the Drobo using Ubunutu to get my system working and to create this guide.

First, I setup an Ubuntu 10.04 installation within a VM image as I tend to change computers and laptops frequently and would like to keep this image for Drobo FS development. As in the noted article, everything will be done within a chroot environment and then copied to the Drobo FS.

Setup the chroot

# install schroot and debootstrap 

sudo apt-get install schroot debootstrap

# create new root 

sudo mkdir -p /var/chroot/drobofs

# create /etc/schroot/chroot.d/drobofs 

cat << END_OF_DROBOFS > /etc/schroot/chroot.d/drobofs
[drobofs]
description=Ubunutu Intrepid for DroboApps on Drobo FS
location=/var/chroot/drobofs
priority=3
users=<Your Username>
groups=<Your Group>
root-groups=root
run-setup-scripts=true
run-exec-scripts=true
END_OF_DROBOFS

# create system in chroot jail 

sudo debootstrap --variant=buildd --arch i386 intrepid /var/chroot/drobofs

Setup the Toolchain

# download the toolchain

# extract the toolchain 

cd /var/chroot/drobofs/usr/local
 
# DroboShare
sudo tar -xjf arm-2006q1-6-arm-none-linux-gnueabi-i686-pc-linux-gnu.tar.bz2
 
# Drobo FS
sudo tar -xjf arm-2007q1-21-arm-none-linux-gnueabi-i686-pc-linux-gnu.tar.bz2
 
## the resulting toolchain is put into a /usr/local/arm-xxx directory
## must either move the files to the parent or put them in the path setting

# copy resolv.conf into the chroot environment 

sudo cp /etc/resolv.conf /var/chroot/drobofs/etc/resolv.conf

Enter the chroot jail

# Optional: if run_setup_scripts is not used for chroot, Mount the required filesystems 

sudo mount -o bind /proc /var/chroot/drobofs/proc

# Activate the chroot to complete setup 

sudo schroot -c drobofs -d /root

Install packages in chroot

# Load some extra packages 

apt-get install vim
apt-get install wget
apt-get install automake autoconf libtool autotools-dev m4

Exit the chroot jail

# type exit to leave the chroot 

exit

Setup the build in chroot

When cross-compiling, you want to use the system's binaries for running development tools but make the compiler and linker using the ARM headers, libraries, and binaries.

From the Drobo FS SDK 1.0:

The following steps can be used to create an application build environment or depending on your needs, you can change the build folders as desired when building multiple applications or targets.

Create a folder for the build

# create a directory for code (or use the specific application name) 

sudo mkdir -p /var/chroot/drobofs/home/build

# create a directory for resulting binaries (or use a specific application name) 

sudo mkdir -p /var/chroot/drobofs/usr/arm

Re-enter the chroot jail

# Activate the chroot to build application 

sudo schroot -c drobofs -d /root

Setup chroot environment for build

The following environment variables will help with building to a non-standard directory: 

export CFLAGS="-I/usr/arm/include -march=armv5te"
export CPPFLAGS=${CFLAGS}
export LDFLAGS="-L/usr/arm/lib"
export CC=arm-none-linux-gnueabi-gcc
# replace /usr/arm as needed to match your build output path