Hi,

1. You should also consider Openembedded www.openembedded.org.
This is a true cross-compilation framework. You can take a fast
multicore x86_64 host and build software for all kind of targets.

The build-tool bitbake was inspired by Portage:
http://docs.openembedded.org/bitbake/html/ch01.html

The config files for the supported hardware are:
http://cgit.openembedded.org/cgit.cgi/openembedded/tree/conf/machine

The TMS320DM356 is supported by
conf/machine/dm365-evm.conf
http://cgit.openembedded.org/cgit.cgi/openembedded/tree/conf/machine/dm365-evm.conf

Just set
MACHINE="dm365-evm"
DISTRO="angstrom-2010.x"
in your local.conf file and call
bitbake minimal-image

But I have not yet built for the target dm365-evm.

The description how I have used Openembedded for the i.MX35 is:
http://en.gentoo-wiki.com/wiki/Phytec_phyCORE-iMX35/Openembedded
and for the MPC5125 is:
http://en.gentoo-wiki.com/wiki/Freescale_TWR-MPC5125/Openembedded

2. I have tried to use Gentoo for cross compilation on x86_64 or x86
hosts for arm and ppc targets. There has been always at least one
software package which cannot be cross-compiled. You have to fix this
before you can go on.

The description how I have tried to cross-compile Gentoo for the i.MX35
is: http://en.gentoo-wiki.com/wiki/Phytec_phyCORE-iMX35/Gentoo/Desktop

3. You can try to use qemu and emulate the native cross-compilation
as described in
http://www.gentoo.org/proj/en/base/embedded/handbook/index.xml?part=1&chap=5

4. You can compile native on the target by using stage3, but are you
sure that you want to do it all the time? Do you have enough memory
there? Do you have swap space? Is the CPU fast enough?
Do you have always the right board at hand?

5. There is also another true cross-compilation framework from
Pengutronix http://pengutronix.de/index_en.html. The description how I
have used it for the i.MX35 is:
http://en.gentoo-wiki.com/wiki/Phytec_phyCORE-iMX35/Pengutronix/Embedded

Pengutronix supports ARM, but I don't know, if it already supports the
TMS320DM365.

I hope this helps.

Best regards

Jan