NeuroKernel v8 — Hardened Autonomy

Mantra: "The OS is not just running on the hardware; it is constantly re-proving the hardware's existence."

NeuroKernel v8 is a radiation-hardened, hardware-software co-designed operating system and Neuromorphic SoC architecture. It is specifically engineered for autonomous operation in extreme environments (Deep Space, High-Orbit, and Nuclear-Proximal) where silicon degradation is not a possibility, but a certainty.

Version 8 marks a shift from Graceful Reconfiguration to Hardened Autonomy, introducing temporal diversity, physical peripheral amputation, and self-distilling neural recovery.

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I. Architecture Overview

The v8 architecture is a vertically integrated stack where every layer—from the gate logic to the scheduling algorithm—is aware of the system's physical integrity.

1. Hardware Layer (ASIC/Verilog)

• Temporal Diversity Interlock [V8: 1-A]: A staggered Triple Modular Redundancy (TMR) unit. Replicas B and C are delayed by 50 and 100 cycles respectively, ensuring that a single transient pulse (SEU) cannot corrupt all three streams at the same logical instruction.
• Credit-Based Bus Arbiter [V8: 1-B]: Implements "Physical Bus Amputation." If a peripheral exceeds its transaction or interrupt budget (indicative of a "Babbling Idiot" fault), the ASIC physically disconnects the peripheral's READY line.
• Transparent RS-Engine [V8: 1-C]: Hardware-accelerated Reed-Solomon (255,223) FEC-SRAM controller providing zero-latency error correction for the software stack.

2. Kernel Layer (Rust Microkernel)

• Ghost Scheduling [V8: 2-B]: High-criticality tasks are dispatched through pseudo-randomly selected entry-point shims. This ensures that the same degraded silicon path is not hit repeatedly, reducing the probability of permanent-fault-induced task failure.
• XOR-Linked Shadow Stacks [V8: 2-A]: Return addresses are XORed with a per-task, per-epoch nonce. This provides spatial and temporal separation for control-flow integrity, turning bit-flips into controlled exceptions.
• Damage-Map PUF [V8: 4-B]: The chip's unique pattern of stuck-at faults is treated as a Physical Unclonable Function (PUF), used to cryptographically sign telemetry.

3. Fidelity Layer (Neuromorphic AI)

• Saliency-Aware Refresh [V8: 3-A]: Neural weights are ranked by criticality. "Hub" neurons are refreshed every epoch via DMA, while "Leaf" neurons are only restored during critical degradation to save power and bus bandwidth.
• Self-Distillation [V8: 3-B]: In UltraDegraded mode, healthy CNN filters re-train/distill weights for damaged filters in the background, allowing the system to "heal" its inference capabilities in-situ.

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II. Engineering Specifications

Feature	Specification
Language	Rust (no_std, nightly)
Target Architecture	RISC-V 32-bit (Rad-Hardened SoC)
Formal Logic	P-TLA+ (Probabilistic TLA+)
Verification	Kani (Symbolic), SymbiYosys (ASIC Formal)
ECC Implementation	RS(255, 223) + CRC-32-C
Scheduling	EDF with Deadline Inheritance + Ghost Shims

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III. Requirements

Toolchain

• Rust: nightly-2024-xx-xx
• Target: riscv32imac-unknown-none-elf
• Simulation: Icarus Verilog (v12+) or Verilator
• Formal Verification: TLA+ Toolbox, Kani Rust Verifier

Hardware (Target)

• NeuroKernel v8 Compliant SoC (or FPGA equivalent)
• 32 KB Sector-Addressable SRAM
• MRAM for Golden Image persistence

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IV. Deployment & Initialization

1. Bootstrap Sequence

The system must be initialized in a specific order to ensure FEC and PMP protections are active before the first task dispatch:

1. GF Table Init: Initialize Galois Field tables for software RS fallback.
2. HW-FEC Probe [V8: 1-C]: Probe FEC_SRAM_STATUS_REG. If present, enable hardware Reed-Solomon.
3. PUF Derivation [V8: 4-B]: Read initial damage map and derive the epoch-1 cryptographic identity.
4. Spatial Allocator Init: Query the ASIC heat map to blacklist "hot" memory sectors.
5. Scheduler Start: Begin EDF dispatching with Ghost Shim rotation.

2. Compilation

# Build the Microkernel
cargo +nightly build --release -p nk-muk

# Simulate ASIC Logic
iverilog -g2012 -o nk_asic_v8 nk-asic/NKAsic.v
vvp nk_asic_v8

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V. Testing & Verification Methods

NeuroKernel v8 utilizes a "Tri-Layer Verification" strategy:

1. Formal Proof (Mathematical)

• TLA+: Proves that P(HighCrit failure) < 10⁻⁹ even at a rate of 5 SEU/hour.
• SymbiYosys: Proves that the Temporal Stagger FIFO never bypasses the TMR voter.

2. Symbolic Execution (Software)

• Kani: Proves that the XOR-Linked Shadow Stack detects any single-bit flip and that the puf_verify function is constant-time.

3. Fault Injection (Simulation)

• Verilog SEU Injection: Random bit-flips are injected into the simulated ASIC's register file to verify TMR capture and majority voting correctness.

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VI. Future Enhancements

• [V9: 1-A] 3D-Aware Spatial Scheduling: Integration with 3D-stacked RAM to steer allocations away from vertically adjacent failing layers.
• [V9: 2-B] Dynamic Distillation Kernels: Allowing ground stations to upload new distillation "teachers" to adapt to unforeseen silicon aging patterns.
• [V9: 4-C] Post-Quantum PUF: Transitioning HMAC-SHA-256 to a quantum-resistant lattice-based signing scheme for multi-century missions.

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Contact: Lead Systems Architect — NeuroKernel Project By The Bunyip
Status: Hardened Autonomy Verified — v8 Baseline Stable