Comment 10 for bug 940339

There are instructions for writing an image to a card on http://www.linaro.org/ if you follow the download link. You could try a pre-built image to save you the trouble of making one of your own. If that works and you want to make your own image, just replace "--mmc <DEVICE>" in your command line with --image-file /path/to/file.

As for formatting cards, I would install gparted and use that since it makes the process trivial. Filling the card up with data should be a simple matter of copying some large files over using whatever method you want and then just cp them back to /dev/null to see if you can read them.