There are plenty of things that have firmware, but run it out of RAM. FPGAs do this, and some microcontrollers. Dialog, now Renasas, has microcontrollers that run their firmware out of RAM.
Commonly there is a hardware peripheral that pulls the firmware from a couple of places (could be an onboard ROM, could be jtag, or other) and loads it in to RAM.
Commonly there is a hardware peripheral that pulls the firmware from a couple of places (could be an onboard ROM, could be jtag, or other) and loads it in to RAM.