You could use objcopy to add a new section to your elf file as follows:
arm-none-eabi-objcopy.exe --add-section .macdata=mac.bin --set-section-flags .macdata=load,alloc --change-section-address .macdata=0x08004000 original_file.elf new_file.elf
where mac.bin is the binary file containing your data and 0x08004000 is the address you want to place it.