Backend: XtratuM

Used on: NG-ULTRA (primary flight-reference backend, together with the XNG tools/flow). Status: Planned (M2).Not implemented in this repository.

Role in the model

XtratuM is the hypervisor of the NG-ULTRA backend. In the flight-oriented reference implementation it is the mechanism that realizes the IR’s partition semantics on the four Cortex-R52 cores:

GoMyRobotOS Contract
      ↓
GoMyRobotOS IR
      ↓
NG-ULTRA Backend
      ↓
XNG / XtratuM       ← this page (hypervisor) + [XNG](xng) (spec/naming layer)
      ↓
RTEMS
      ↓
GoMyRobotRT

Ecosystem basis (recorded facts from the M0 baseline)

The architecture records that NG-ULTRA has an established ecosystem around RTEMS and XtratuM/XNG, that existing RTEMS work lists an ARMv8-R NG-ULTRA BSP, and that NanoXplore’s ecosystem includes RTEMS and XtratuM/XNG support. Those are ecosystem facts used to justify the backend choice - not claims by this repository.

What M2 must produce

The GoMyRobotOS NG-ULTRA backend:

maps IR partition semantics to XtratuM configuration,
realizes the declared memory/interrupt/DMA/device separation,
hosts RTEMS as the partition runtime,
boots the reference flight partition with Status: Flight Reference / Development.

M2’s gate: NG-ULTRA executes the same conceptual flight partition as the x86-64 reference (M2).

Documentation discipline

Until M2 validation exists: no timing claims, no interference claims, no “isolation guaranteed” phrasing anywhere in this repository about XtratuM-backed partitions. The validated-properties table for this backend is empty by design at M0.