Hi Mahendra,
Here is a helpful forum link:
https://www-secure.symantec.com/connect/forums/sep-121-linux
Machines running SAV for Linux will not count against the SEP 12.1 licensed seats.
And I can confirm: SEP for Mac can be managed directly from the SEPM with policies, logs, etc. It must download its updates from the Internet LiveUpdate servers, though, or from an in-house LUA 2.x server.
Hope this helps! Please do update this thread if there is anything more you need.