Reset Sequencing: Step-by-Step Walkthrough

Step-by-step analysis walkthrough

Use this sequence when owning Reset Sequencing in a signoff review.

1. Inspect warning class and severity.

2. Trace crossing endpoints and domains.

3. Check protocol/reset assumptions against spec.

4. Review synchronizer or FIFO implementation detail.

5. Run focused assertion or formal check.

6. Draft fix options with risk and schedule impact.

7. Execute regression and publish closure memo.

Artifacts to collect

• bring-up sequence spec, dependency matrix, firmware reset script

• crossing inventory

• waiver board notes

• regression report

Decision memo template

CDC/RDC DECISION MEMO — Reset Sequencing
risk class:
mechanism:
evidence:
fix/waiver:
owners: SoC integration owner, firmware owner, RTL lead

Reference visuals

Reset dependency graph

always-on reset release
      -> clocks stable
      -> fabric/control release
      -> data-path release
      -> peripheral release

Violation causes boot races and phantom deadlocks.

CDC/RDC deep dive

Reset release ordering is a first-order reliability contract.

Concept diagram

RESET RELEASE FLOW

assert global -> clocks stable -> sync release per domain -> first transaction

Metric graph

BOOT STABILITY

passes per 1k boots: 920 -> 980 -> 999

Reports and artifacts

• reset dependency matrix

• RDC warning classes

• boot stress logs

• waiver aging

Mini case study

Domain B released before producer A was valid, causing rare startup deadlock.

Debug branches

• Correlate reset and clock timelines

• verify async assert/sync release

• exercise skewed release tests

Senior review question

Ask: what evidence proves this risk is closed for silicon, not just tool-clean?

Key takeaways

• State crossing class, assumptions, and owner with every issue.

• Run structural and dynamic regressions after each fix.

Common pitfalls

• Treating all warnings as equivalent risk.

• Waiving issues without containment evidence.

• Skipping reset and reconvergence stress after CDC fixes.

Principal CDC/RDC review addendum

Reset ordering enforces dependency contracts so control domains and memories become valid before downstream consumers execute.

Metric: domain bring-up order violations, dependency deadlocks, reset latency