Negsman/radiate-os-bios-sim

BIOS Sim Harness — Radiate OS (Steps 0–5)

Simulated boot engine for the Radiate OS host substrate. Validates the boot decision logic (header parsing, checksum verification, clean-shutdown evaluation, PCIe BAR mapping, fault handling) against mock NVMe blobs, before any real hardware is touched.

Status

• Step 0 header integration: include/radiate_sector_header.h is a DRAFT of the binary contract for Adam's approval/correction. Jim's assignment says Adam is specifying the layout; this file is Nova's proposed C-struct for it, built from the agreed contract fields in the Master OS Roadmap (64-bit magic, version bitmask, BLAKE3 checksum, sector type flags, CLEAN_SHUTDOWN bitmask). Nothing here is locked until Adam confirms it.
• Step 2 BIOS Sim harness: implemented (boot engine + mock blob generator + test suite). See "What it does" below.

What it does (Step 2 milestone, from Jim's assignment)

The simulated boot engine (bios_sim_boot) ingests a mock NVMe binary blob and:

1. Parses sector header signatures — magic, version, sector type.
2. Evaluates the Clean-Shutdown bitmask — CLEAN_SHUTDOWN set means normal boot; clear (dirty) means improper shutdown and bitstream rollback to the last clean snapshot.
3. Maps early PCIe BAR allocation for GDDR6 VRAM execution — BAR0 (GPU control regs), BAR1 (GDDR6 VRAM), BAR2 (snapshot/scratch).
4. Triggers user-mode fault handlers if checksum validation fails — the fault handler logs the fault and fails closed (halts boot), the way the microkernel's user-mode isolation will in the real OS.

Layout

bios-sim/
  include/
    radiate_sector_header.h  Step 0 binary contract (DRAFT)
    bios_sim.h               Boot engine API
    checksum.h               BLAKE3 wrapper API
  src/
    bios_sim.c               Boot engine implementation
    checksum.c               BLAKE3 wrapper (vendored reference impl)
    mock_blob.c              Mock NVMe blob generator (CLI)
    blake3/                  Vendored BLAKE3 reference implementation
  tests/
    test_boot.c              Boot-engine test suite
  Makefile

Build and test

make test

This builds mock_blob and test_boot, then runs the suite (10 cases: clean host/LLM boot, dirty rollback, dirty with no snapshot, bad magic, bad version, bad type, bad checksum, pre-checksum payload corruption, missing file, plus BAR-table verification on boot paths).

Checksum rule

The BLAKE3 digest covers the header with the checksum field zeroed, followed by the payload bytes. A reader verifies by zeroing the checksum field, hashing header + payload, and comparing against the stored digest. This avoids the circularity of a checksum covering itself. The sim uses real BLAKE3 (vendored reference implementation), so the boot logic is validated against real digests.

Handing off to Sprint

Jim's direction: pass initial commits to Sprint as each module is completed so he can start harness auditing. The transfer channel is Hugging Face (per Adam, Nov 8). This directory is the module; hand the whole bios-sim/ tree over when Adam says go.