Here it is

http://osm.pleiades.uni-wuppertal.de/garmin/routable/01-04-2012/29580c641011e85b79292d1547b6be26

In any case I have used this command in Windows

java -jar mkgmap.jar --tdbfile *.img

and I could generate the .tdb file. Is it the same command also in Linux?