QSF: set fitter placement SEED 3 (bounded sweep winner)
RTL frozen at 6319d7c. The AW/W/R buffers + F_SETTLE drain multicycle
removed every structural EMIF-handshake -> FSM setup family; the residual
was a placement/route-marginal EMIF path (zc_emit QUAD_WIDTH4 Z-request
FIFO read, ~-0.087 ns: 3.132 ns data / -0.100 ns skew vs 3.225 ns period).
A bounded, Codex-authorized 4-seed fit+STA sweep (AGGRESSIVE AREA kept,
no asm) resolved it by placement:
seed 2 EMIF -0.087 (10 violated)
seed 3 EMIF +0.132 (0 violated, ALL classes >=0) <- winner
seed 4 EMIF +0.062 (0 violated, under +0.100 margin)
seed 5 EMIF -0.130 (3 violated)
SEED 3 is the best complete result: EMIF setup +0.132 (>= +0.100),
design +5.561, hold/recovery/removal/MPW all nonnegative, no AWREADY /
texture-fill R-return / texcache drain / scanout-diagnostic violations,
RAM 317/358, ALM 85%. This is a fitter placement seed only -- no RTL or
optimization-mode change. Per-seed reports preserved under
synth/.../seed_sweep/ (not committed; build artifacts).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
thejayman77
0c9b2bf5cd