nx_driver_shapes.nx

SUPERSEDED 2026-06-13 (no-sprawl consolidation): the CANONICAL driver-from-spec path is the op-list-driven nx_drv_proto_emit.nx (a new device class = a new op-list SPEC, zero emitter change). This shape library + its consumer nx_drvgen are KEPT only as the byte-identical virtio re-emit regression reference (NVMEGATE stage=B PROOF-1). See nx_drvgen.nx header + nvme_oplist_virt.spec. nx_driver_shapes.nx -- the DEVICE-AGNOSTIC driver shape library (X-DRV-W1 stage A). This is the emitter-of-emitters substrate for driver bring-up: a tiny rv64 mini-encoder plus four SPEC-DATA-DRIVEN emit-op families that, between them, express the structure of ANY register- programmed device-init driver. ZERO virtio (or NVMe) identity is baked here -- every offset and constant an op touches arrives as a PARAMETER, pulled by the caller from a generic field table. The device identity lives entirely in the spec; this library only knows how to turn (offset, value) tuples into bytes. The four shapes: WIRE_TLV verify "reg-at-offset == const" / write "const -> reg-at-offset". The bring-up handshake is a list of WIRE_TLV ops (virtio MagicValue/Version/DeviceID verifies + Status ORs; NVMe would be CAP/VS verifies + AQA/ASQ/ACQ writes). Provided by ds_emit_verify / ds_emit_verify_u / ds_emit_regwrite. COMMAND_QUEUE bind a queue (write base/PFN regs) + kick a doorbell/notify + read an instrument register back and verify it. virtio's QueuePFN+QueueNotify and NVMe's ASQ/ACQ+ SQyTDBL are the SAME op over different spec rows -- the caller threads the bind regs, the kick reg/val, and the result reg/expected. The read-back verify is ds_emit_verify / ds_emit_verify_u; the kick is ds_emit_regwrite. STATE_MACHINE an enable/progress step that is EITHER monotonic-OR-write (virtio Status) OR write-then-poll-until-bit-set (NVMe CC.EN -> CSTS.RDY). ds_emit_regwrite covers the OR-write half; ds_emit_poll_until_set synthesises the poll-loop control flow (a real backward branch) from a spec field -- the structure comes from DATA, not from code (the eoe / X-AUT-006d principle). Virtio uses only the OR-write half; the poll half is exercised by the 2nd device class (stage B). STRUCT_WALK store struct fields at base_reg + memoff with width w, driven by a field table (off, width, value). virtio's 16-byte split-virtqueue descriptor and NVMe's 64-byte SQE are the SAME op over different field tables. Provided by ds_emit_memstore (and ds_li32 / ds_li32u for materialising a struct base addr). Byte-reproducibility: every op keeps the two-pass measure/backfill invariant of the original virtio emitter (instruction COUNT identical across passes; only immediates differ), so a forward fail-branch target is structurally derived, never typed. This file is lifted VERBATIM (byte-for- byte logic) from nx_virtio_hs_emit's encoder so the refactored virtio emitter that now CALLS these ops re-emits its image byte-identically (the stage-A regression guard). Sovereign: pure integer arithmetic, no syscalls beyond what the importer pulls in via nx_syscalls. license_tier: ORIGINAL