Why ARM provides the extension .axf in its binary generation ? Is it ARM proprietary format or the general ELF format and the extension is private ?
ARM's tools have traditionally used the extension .axf for image files, but this naming is not compulsory and most tools will accept different extensions too. The file format follows the ELF standard, and often also containing debug information that follows the DWARF standard. Third-party tools that follow the ELF and DWARF standards should be able to consume these files too.