Files
FPGA-Neural/hardware/v2/logs
micheleandClaude Sonnet 5 175f697ae1 feat(v2): M4 Memory Manager + Prefetch Engine, real V1 PSRAM backend
Implements M4: memory_manager.v (arbitration/buffering/forwarding/
latency hiding/double buffering, §12) + prefetch_engine.v
(double-buffered tile fetch, §13), sitting on the REAL, UNMODIFIED V1
PSRAM backend chain (int8_memory_access.v -> memory_interface.v ->
psram_controller.v, per §15's explicit mandate not to touch the
controller).

Verified fully end-to-end with Verilator: real neural_processor (M1)
fed entirely by memory_manager, computing against PSRAM-resident X/W
tiles (double-buffered prefetch across up to 5 tiles) and writing its
result back to PSRAM -- checked via an independent PSRAM read-back,
with poison bytes around the operand regions to catch addressing
errors. 3/3 jobs pass (1/3/5-tile configurations).

Three real RTL bugs found and fixed during integration (full
diagnostic trail in errors.log ERR-0006): prefetch_engine had no
single-in-flight-request discipline, letting a queued request corrupt
the bank bookkeeping of a fetch already running; the fix's own
!pf_busy guard had a one-cycle blind spot (pf_busy lags pf_start by a
clock) that needed an explicit !pf_start term; and a state-based mux
for the shared backend port was off by one cycle, silently dropping
the PSRAM result write entirely.

Real synthesis: 0 CHECK problems, 851 LUT4/789 FF/108 CCU2C/0 DSP
(expected, no multiplication in this module). Real place&route (via a
synthesis-only timing harness, needed for the same TRELLIS_IO pin-
budget reason as M2's array): Fmax 165.86 MHz, PASS at 80MHz.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_013xXuuRUWZScuo1DeYJxs3v
2026-09-05 14:39:29 +02:00
..

Formato dei log V2

Regola non negoziabile (docs/v2-description.md §25-29): ogni attività significativa (modifica, simulazione, sintesi, benchmark, decisione, errore) deve essere registrata. Nessun log viene mai sovrascritto o troncato — solo append. Nessun ID esperimento (EXP-XXXX) o decisione (DEC-XXXX) viene mai riutilizzato, anche se il risultato è un FAIL.

File

  • development.log — log principale di sviluppo, un'entry per ogni sessione di lavoro/milestone (creazione file, refactor, avanzamento roadmap).
  • architecture.log — decisioni e note di architettura a grana fine (non scelte finali — quelle vanno in decisions.log — ma esplorazioni, alternative considerate, vincoli scoperti).
  • simulation.log — ogni run di simulazione (Icarus/Verilator): test, vettori, cicli, PASS/FAIL, confronto bit-exact con V1, stall/memory-wait.
  • synthesis.log — ogni run Yosys: LUT/FF/DSP/BRAM, warning, problemi CHECK.
  • timing.log — ogni run nextpnr-ecp5: Fmax, percorso critico, WNS/TNS se disponibili. Fmax "ufficiale" di una configurazione = solo da qui, mai da simulazione o stima.
  • benchmark.log — tabelle di confronto per configurazione (Fmax, MAC/cycle, cycles/neuron, utilization, ecc.), sempre con etichetta THEORETICAL/SIMULATED/SYNTHESIZED/POST-P&R.
  • decisions.log — decisioni architetturali importanti, formato DEC-XXXX (vedi docs/v2-description.md §27).
  • experiments.log — registro principale, un EXP-XXXX per ogni esperimento end-to-end (config → sim/synth/timing → risultato), rimanda a reports/experiments/EXP-XXXX/.
  • errors.log — errori/bug/regressioni incontrati durante lo sviluppo V2 stesso (non i bug V1, già chiusi in hardware/v1/docs/validation/bugs.md).

Campi minimi per entry (§26)

timestamp, experiment_id (se applicabile), git_commit, session/agent,
module, configuration, action, reason, command, result, errors, decision,
next_action

Per synthesis/timing aggiungere: LUT, FF, DSP, BRAM, Fmax, critical path, WNS/TNS. Per simulazione: test, vectors, cycles, PASS/FAIL, bit-exact result, stall cycles, memory wait, utilization.