Low Power Verification · All levels
UPF Recap for Verification Engineers: Debug Playbook
Debug Playbook for UPF Recap for Verification Engineers.
Debug playbook
Debug Playbook for UPF Recap for Verification Engineers 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.
Freeze seed, metadata, and boundary under investigation.
Locate first persistent low-power phase divergence.
Classify mechanism: setup, transition, boundary, retention, or X-prop class.
Apply one focused reproducer and one bounded fix.
Re-run determinism and broader regression matrix.
Review memo template
LPV REVIEW MEMO - Low Power Verification Foundations / UPF Recap for Verification Engineers
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: UPF concepts most relevant to verification include power domains, supply sets/nets, power switches, isolation strategies, retention strategies, level shifters, and power state tables. Verification use of UPF is not only syntax familiarity; it is semantic understanding of what each construct guarantees and what must be checked in simulation and formal. Engineers should validate that UPF intent is complete, consistent, and correctly bound to RTL hierarchy, then verify key properties: isolation asserted before source-off, retained elements restored correctly, legal voltage crossings protected, and only valid power states entered according to PST definitions.
- 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 UPF Recap for Verification Engineers: 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 escalateLow-power verification deep dive
LPV foundations are strongest when power intent, simulation semantics, and ownership boundaries are explicit from day one.
Concept diagram
LPV FOUNDATION LOOP
intent definition -> setup and modeling -> scenario execution -> evidence-based closure
^ |
+------------------------ owner feedback ----------------------+Metric graph
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.