bspdn-goal-driver

Drive BSPDN objective optimization toward target outcomes (about 8% dynamic-power reduction without area/timing regression, or 5%+ frequency uplift with non-worse power/area) using gated experiments and evidence tracking.

BSPDN Goal Driver

When to use

Use this skill when the user asks to push objective/performance toward explicit PPA goals, not just run exploratory experiments.

Goal contract

Target A:

  • dynamic power reduction about 8%,
  • area/timing non-worse (delta_area<=0, delta_wns>=0, delta_tns>=0).

Target B:

  • power/area non-worse,
  • frequency uplift >=5% validated by period-sweep evidence.

Milestone policy (incremental, mandatory)

Do not pursue one-shot final target. Use staged gates:

  1. M0: evidence-valid baseline and repeatable A/B flow (execution-contract PASS).
  2. M1: power <= -1% with non-worse area/timing.
  3. M2: power <= -3% with non-worse area/timing.
  4. M3: power <= -5% with non-worse area/timing.
  5. M4: final target A (~ -8%) or target B (>=5% frequency uplift with non-worse power/area).

Promotion to next milestone requires current milestone PASS + retrospective note.

Workflow

  1. Build/update goal tracker:
python3 scripts/debug/track_bspdn_goal_progress.py --campaign-md <ppa_md> --out-prefix <prefix>
  1. Select testcase tier:
  • Tier-1: high backside-usage potential with route feasibility,
  • Tier-2: mechanism-isolation testcase for fast iteration.
  1. Run pre-submit checks:
  • eda-preflight-reflect
  • route smoke (smoke_targeted_backside_route_toycase.sh) for targeted net lists
  • execution policy lock (vanilla_replace primary baseline)
  1. Execute A/B campaign with strict gates:
  • shared baseline and route policy,
  • explicit net-selection policy/version tag,
  • collect route PPA and execution-contract artifacts.
  1. Decision:
  • GO only when current milestone gate is satisfied with valid artifacts,
  • otherwise update hypotheses and next-step campaign.

Outputs

  1. bspdn_goal_progress.summary.md
  2. bspdn_goal_progress.detail.tsv
  3. campaign plan (goal_campaign_plan.md)
  4. evidence-backed milestone decision note (M0/M1/.../M4).

Reporting policy (user-facing)

  1. Do not generate slides for every process stage.
  2. Generate a PDF version-summary only when a new validated version reaches a reporting milestone:
    • first reach >=2% power reduction with non-worse area/timing,
    • then each higher validated step (for example >=3%, >=5%, final target),
    • or Goal-B (>=5% frequency uplift with non-worse power/area).
  3. Each version-summary slide deck must include method delta, key conclusions, core PPA table, and next-step plan.

Hard rules

  1. No promotion claim without execution-contract PASS.
  2. Goal-B frequency claim must come from period sweep, not WNS proxy alone.
  3. Record exact selector/route-hint config for each compared run.