BSP Nomenclature

This might seem like a noob question but I keep running into this
issue when building rtems tools.

Is there some master list of the  *explicit* bsp option to pass to
"--with-rtems-bsp"?
I remember not having the *exact* bsp expression being an issue when
building tools. Getting
it wrong (as I recall) causes things to (silently) not work right.

BTW: having just spent some time debugging my m68k target tool builds
for both 6.1 and 5.3
I find in the configs what appears to be an issue where if one does
not define a bsp for tool
building the library options for gcc will not be generated. :/

Robert W.