I'm not exactly sure what you're asking here.
The .ELF as a binary image is NOT directly executable, it's an object file containing many sections, including symbols, debug information, and sections which load into memory at specific addresses.
For a binary image that lives in FLASH you'd need to use a "elf2bin" type extraction, perhaps via objcopy
A .HEX also doesn't directly go into memory, but is an ASCII representation of the bytes, with each line of the file describing bytes going into a specific address, and having a checksum for that line of data. The file is generally digested in a linear form, with the parser recovering the length, address and content, and then writing that payload into the FLASH at the prescribed address.
Could you run the update from ITCMRAM, yes, but typically one would use the front portion of the FLASH to be a LOADER, which can copy itself to RAM for speed, but then write content deeper into FLASH where you want you APPLICATION to dwell.
Over what interface do you plan of sending the update?
