halogen-flash-server already ships an NPU path on the pin we run: for each
model named in HALOGEN_NPU_MODELS it loads the vendor's precompiled AIE
programs (XDNA2 executes only AIE-compiled graphs) and answers them on
/v1/embeddings inside the SAME container behind port 7770. That gives the
fleet an in-house embedding endpoint without touching the iGPU trunk.
The lane is opt-in and one line wide: HALOGEN_NPU_MODELS blank is the
pre-lane endpoint byte for byte (no device, no mounts, no engine env).
The three host preconditions the vendor names are gated in the serve script
and mirrored in the deployer (the 2026-10-01 twin law), each refused by name:
- the staged model files. /models is read-only and HALOGEN_DOWNLOAD stays
unset so the container opens no outbound connection at boot, so
scripts/download-frank-dragoon-npu.sh stages them from the pinned
revision with the catalog's own byte counts and sha256s (the engine
re-checks both at boot);
- the distro XRT's libxrt_coreutil/libxrt_core/libxrt_driver_xdna, each
mounted twice — where the image looks for XRT and at its own path —
because those libraries find each other where they were installed and
an /opt/xilinx/xrt of symlinks dangles inside the container;
- the GPU fabric clock HELD. On Strix Halo the iGPU and the NPU co-running
hang the machine (and corrupt NPU results) while FCLK changes speed, and
halogen refuses to start in that state; it cannot read host sysfs from
inside, so the hold is proven host-side. dankclaw/host/ carries the
vendor's halogen-fabric-clock{,.service} verbatim at tag v0.16.2 (sha256
a3a4f7f4e0142e71… / 5f9f1cc4c85a1c02…); the deployer installs, enables
and gates it only while the lane is named, and releases the clock plus
drops the boot hook when it is not.
After health, the deployer's lane gate is a real embedding through
/v1/embeddings — a 200 on /health proves nothing about the NPU programs.
Planner: dankclaw/host/halogen-fabric-clock* re-dispatches frank-dragoon
(the deployer installs it); dankclaw/host/grub and the fetch script plan
nothing.
Seam: 11 new tests — the off arm really renders nothing lane-specific, the
on arm renders the device/mounts/env, every missing precondition refuses by
name, the deployer twins and the host unit shape are pinned.
Co-Authored-By: omp <omp@dankclaw>
The 2026-09-11 trade bought a vendor-claimed 13-16% prefill figure that was
never measured here; the 2026-10-18 research (same decision record) shows what
identity mode actually costs the iGPU is the 1:1 page walk plus ATS/PRI/PASID/
GCR3 -- worth 2-4% on this silicon class, and removable outright by AMD PerfOpt
when the distro ships Linux 7.4. Meanwhile pt is what err=-19 asks for: the
XDNA2 NPU binds its own IOPT_TYPE_SVA domain and only needs the IOMMU enabled.
Measured off-vs-pt prefill arms follow in the docs commit; frank-archon
(Dankserver) is untouched.
/etc/default/grub was host-only state while the IOMMU boot line was the most
consequential kernel decision on the box (the 2026-09-11 amd_iommu=off adoption
lived only in the decision record). Fetched byte-exact (1581 B) and paired with
scripts/set-dankclaw-bootline.sh: refuses any host but dankclaw, shows the diff,
installs 0644 root:root, runs update-grub, names the pending token, and reboots
only on --reboot. The deployer plans nothing under dankclaw/host/ by design —
kernel state is not a container restart.
Frankandomp