XEMU (2020/11/12) is released. xemu is an open-source, cross-platform application that emulates the hardware of the original Xbox game console, allowing users to play their Xbox games on Windows, macOS, and Linux systems. This project is focused on making significant forward progress in terms of features, performance, stability, and user experience in Xbox emulation. This project is an active fork of the XQEMU project, which is based on the very popular and highly actively maintained QEMU full system emulator project.

XQEMU Git Changelog
xbox: Make flash ROM memory regions writeable
In lieu of proper writeback cache emulation, mark the flash ROM memory
region(s) as writeable. This is necessary to enable later Xbox kernel
revisions which write to a single address within this region during very
early startup code and expect the written value to persist when read
back in the next instruction. See comment in patch for more details.