toolchain wit Debian 64bit

Yes, there may be some additional packages required. On Fedora 21, you usually need the following additional packages to compile buildroot:

glibc (i686), glibc-devel (i686), zlib (i686), wget, perl-ExtUtils-MakeMaker, texinfo, git.

Here "i686" means the 32-bit version of the package.

About the path of the toolchain. This is already given as a warning in our FirstSteps documentation (chapter 7.1):

Quote

The cross-compile toolchain is needed to compile U-Boot, the Linux Kernel and the Buildroot
package. We recommend installing it globally in directory /usr/local/arm. This is the directory
that is preset in some configuration files. If you use a different directory, you may
have to modify these configuration settings before being able to build packages, for example
in Buildroot.

Your F&S Support Team

Changing the location of the toolchain is not possible, that's true. We installed all the tools onto another partition (which is in the backup).
The easiest solution for us was to set a symlink.

ln -s /opt/toolchain/fs-toolchain-4.7.2-cortexa5-neonvfpv4 /usr/local/arm

If this is not possible for you, you can also use mount with the "bind" option.

Setting a link is also a very good idea. However I would recommend setting it without the fs-toolchain directory, because the fs-toolchain directory is already part of the configuration.

Your F&S Support Team