Where can I acquire gdbproxy?

Can you find bfin-gdbproxy ?

I can't.  I extract "blackfin-toolchain-uclibc-full-2014R1_45-RC2.x86_64.tar.bz2" but when I perform a "find | grep gdb" I only see libraries and what look like python scripts

Please download the package named "blackfin-toolchain-elf-gcc-4.5-2014R1_45-RC2.x86_64.tar.bz2"

This is where it is, thank you !

You've answered my primary question.  I have a secondary question however, which is:

Can bfin-jtag (and subsequently bfin-gdbproxy) interact with ADZS-BF537-EZLITE via its inbuilt USB debugger?

It seems perhaps IGLOO driver can be used for this?  "cable probe" only reveals "automatic probe found nothing"

Please advise - thank you

No. UrJTAG and gdbproxy do not support the on-board emulator. The on-board emulator on BF537 EZLITE board is not an IGLOO emulator, so the IGLOO driver will not work for it.

Does this mean the on-board emulator has no linux host support?  My intent is to try ucLinux/buildroot on the EZKIT, then use linux to program it.  But of course I'll need to load the image onto it.  Perhaps I should start a different thread for that purpose

The on-board emulator on BF537 EZLITE board does not have Linux support. You can take a look at the cables supported by UrJTAG here:

https://sourceforge.net/p/urjtag/git/ci/master/tree/urjtag/src/tap/cable/

to see what's available to you. You'd better choose an emulator with schematics available such that you can connect the signals from emulator to the JTAG port on the board correctly.

Alright then.  This saves me a lot of R&D time.  Likely I'll open a different question thread later on.  Thank you again!

Sorry, I just notice your 2nd question. It's too late. But the the answer is no. bfin-jtag or bfin-gdbproxy does not support the builtin USB debugger.