Low Power Verification · All levels

Power Intent Overview for Verification: Debug Playbook

Debug Playbook for Power Intent Overview for Verification.

Debug playbook

Debug Playbook for Power Intent Overview for Verification is anchored on illegal transition rate, corruption incidence, and deterministic replay quality under low-power scenarios. Convert observations into mechanism-backed and owner-bound actions.

  1. Freeze seed, metadata, and boundary under investigation.

  2. Locate first persistent low-power phase divergence.

  3. Classify mechanism: setup, transition, boundary, retention, or X-prop class.

  4. Apply one focused reproducer and one bounded fix.

  5. Re-run determinism and broader regression matrix.

Review memo template

diagram
LPV REVIEW MEMO - Low Power Verification Foundations / Power Intent Overview for Verification

1. Symptom
   - Failing metric: illegal transition rate, corruption incidence, and deterministic replay quality under low-power scenarios
   - Trigger context: <seed/mode/sequence>
   - First failing phase: <entry/off/exit/boundary>

2. Mechanism hypothesis
   - Candidate mechanism: Power intent defines how and when a design is allowed to consume energy, and verification must prove that those intent rules hold in dynamic operating conditions. In practice, this means understanding power domains, legal states, control signals, isolation boundaries, retention boundaries, and supply relationships so tests can target transitions instead of only steady-state behavior. Verification engineers should treat power intent as executable specification: every declared low-power structure implies expected behavior during power-up, power-down, wake-up, reset interaction, and cross-domain communication.
   - Competing hypotheses: setup, transition race, boundary bug, retention drift, X-prop noise
   - Missing evidence: <trace/assertion/report>

3. Proposed action
   - Smallest reversible change: <intent/RTL/checker/flow>
   - Expected movement: <failure trend/replay stability>
   - Regression risk: compatibility, coverage, signoff delay

4. Signoff
   - Required artifact: evidence packet for Power Intent Overview for Verification: transition timeline, assertions, and before-after replay summary
   - Required owners: LPV lead, power-intent owner, Low Power Verification Foundations owner
   - Final decision: ship, bounded rollout, rollback, or escalate

Low-power verification deep dive

LPV foundations are strongest when power intent, simulation semantics, and ownership boundaries are explicit from day one.

Concept diagram

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LPV FOUNDATION LOOP

intent definition -> setup and modeling -> scenario execution -> evidence-based closure
       ^                                                              |
       +------------------------ owner feedback ----------------------+

Metric graph

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FOUNDATION HEALTH

setup escapes             █████
intent mismatch defects   ██████
stable regressions        █████████

Metrics and artifacts to collect

  • intent-to-RTL alignment checklist

  • power-mode onboarding packet

  • ownership map for controls and checks

  • first-failure boundary report

Mini case study

A project reduced LPV bring-up churn after requiring explicit domain-control ownership and transition evidence in every review.

Debug branches

  • Prove setup correctness before chasing downstream symptoms.

  • Record domain ownership for each control and checker.

  • Distinguish intent mismatch from RTL implementation bugs.

Senior review question

Ask: what exact low-power transition boundary failed first, and which artifact proves the closure claim reproducibly?

Key takeaways

  • Tie each LPV claim to a concrete transition boundary and one proving artifact.

  • Prefer minimal reversible fixes with explicit owner and rollback criteria.

Common pitfalls

  • Treating power-aware failures as random before boundary classification.

  • Waiving X-prop failures before proving impact and root cause.

  • Declaring closure without deterministic replay across key modes.

Debug ladder

Sequence: reproduce -> classify -> isolate boundary -> prove mechanism -> bounded fix.

Avoid mixed fixes before first-principles classification.