You don't need to make install the binary, this often strips the binary removing all the debug information.
In the HACKING file these is a section on how to debug this tool, they advise the following settings, personally I would add -ggdb to enable gdb specific bindings. (This advice also applies to other projects, although this project has explicitly added ...
If you have SWD you should be able to get at least the device ID or determine the device family. For example, most Cortex-M devices have a pretty uniform memory map.
You can also probe memory reads (e.g. each 0x1000 bytes) to determine what addresses are valid.