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Course contents

  • How to Use This Course
  • Low-Power Metrics Reference
  • Low-Power Glossary
  • Reading Path
  • Power Intent Fundamentals61
    • Supply Sets & Power States
    • Power Domain Basics
    • UPF Object Model
      • UPF Object Model: Mechanism
      • UPF Object Model: Inputs & Outputs
      • UPF Object Model: Reports & Metrics
      • UPF Object Model: Debug Playbook
      • UPF Object Model: Worked Example
      • UPF Object Model: Pitfalls & Red Flags
      • UPF Object Model: Interview Drills
      • UPF Object Model: Review Checklist
      • UPF Object Model: Theory Deep Dive
      • UPF Object Model: Design Space
      • UPF Object Model: Expanded Case Study
      • UPF Object Model: Step-by-Step Walkthrough
      • UPF Object Model: Comparison Matrix
      • UPF Object Model: Software / Programmer View
      • UPF Object Model: Silicon PPA Impact
    • CPF vs UPF
    • Power Intent Fundamentals: Tricky Q&A
  • Isolation & Retention61
  • Level Shifters & Power Switches61
  • UPF Implementation Flow61
  • Low Power Verification61
  • PD & Power Grid Integration61
  • Low Power Interview Prep4
  • Low Power / UPF Cheatsheet
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‹Power Intent Fundamentals
  1. Topics
  2. Low-Power Design
  3. Power Intent Fundamentals
  4. UPF Object Model

Low Power / UPF · All levels

UPF Object Model

Power Intent Fundamentals: UPF objects (domains, supply nets, sets, strategies, controls) form a graph that tools resolve from RTL through implementation.

  • 15topics
  • 15lessons

Topics in this section

  1. 1UPF Object Model: Mechanism1 lesson
  2. 2UPF Object Model: Inputs & Outputs1 lesson
  3. 3UPF Object Model: Reports & Metrics1 lesson
  4. 4UPF Object Model: Debug Playbook1 lesson
  5. 5UPF Object Model: Worked Example1 lesson
  6. 6UPF Object Model: Pitfalls & Red Flags1 lesson
  7. 7UPF Object Model: Interview Drills1 lesson
  8. 8UPF Object Model: Review Checklist1 lesson
  9. 9UPF Object Model: Theory Deep Dive1 lesson
  10. 10UPF Object Model: Design Space1 lesson
  11. 11UPF Object Model: Expanded Case Study1 lesson
  12. 12UPF Object Model: Step-by-Step Walkthrough1 lesson
  13. 13UPF Object Model: Comparison Matrix1 lesson
  14. 14UPF Object Model: Software / Programmer View1 lesson
  15. 15UPF Object Model: Silicon PPA Impact1 lesson
On this page

    What this topic teaches

    UPF Object Model translates low-power intent into release-grade evidence. UPF objects (domains, supply nets, sets, strategies, controls) form a graph that tools resolve from RTL through implementation. The practical challenge is proving policy correctness under real transitions and ensuring each owner closes their layer without semantic drift.

    The senior-engineer question

    When UPF lint violations, unresolved object references, and policy binding success regresses, can you identify the failing transition, policy owner, implementation evidence, and minimum regression that proves closure?

    Diagram
    POWER INTENT FLOW — UPF Object Model
    
    architecture intent
          |
          v
    UPF objects (domain/supply/state/strategy)
          |
          v
    RTL + synthesis + PD interpretation
          |
          v
    verification + signoff evidence
          |
          v
    release decision
    
    Primary metric: UPF lint violations, unresolved object references, and policy binding success

    Picture the low-power flow

    Start with domain/state diagrams before diving into logs. These are the models to sketch in design and interview reviews.

    UPF object graph

    Diagram
    UPF OBJECT GRAPH
    
    create_power_domain
        -> create_supply_net / create_supply_set
        -> create_pst (power states)
        -> set_isolation / set_retention / set_level_shifter
        -> map controls (PMU signals)
    
    Broken references become silent intent drift.

    Domain map

    Diagram
    POWER DOMAIN MAP — UPF Object Model
    
      +------------------- always_on -------------------+
      | PMU / control / retention rail                  |
      +---------+----------------------------+----------+
                |                            |
       +--------v---------+         +--------v---------+
       | domain_A         |         | domain_B         |
       | switchable       |<------->| switchable       |
       | iso/ret controls | crossings require policy   |
       +------------------+         +------------------+
    
    Domain boundaries are policy boundaries, not drawing boundaries.

    State transition path

    Diagram
    STATE TRANSITIONS — UPF Object Model
    
    ON  --save-->  RETENTION  --off-->  OFF
     ^               |                    |
     |               +----restore<--------+
     +--------------------power_up--------+
    
    Guard checks:
      - isolation asserted before OFF
      - restore before functional traffic
      - reset policy consistent with retained state

    Ownership layers

    Diagram
    LP OWNERSHIP LAYERS — UPF Object Model
    
    layer                owns                          typical failure
    ------------------   ---------------------------   --------------------------
    architecture         domain strategy               infeasible power states
    UPF intent           policy objects + bindings     wrong/missing policy
    implementation       LP cell insertion/routing     illegal physical behavior
    verification         transition scenarios          uncovered LP bug
    signoff governance   waiver + release decisions    late escape to silicon

    Evidence to collect

    • Primary metric: UPF lint violations, unresolved object references, and policy binding success.

    • Primary artifact: UPF lint log, object resolution report, and policy summary.

    • Owners to bring into review: UPF owner, CAD owner, integration lead.

    • One failing transition timeline with state markers and control signals.

    • One report snippet proving policy intent versus implementation behavior.

    Ownership map

    Diagram
    OWNERSHIP MAP — UPF Object Model
    
    artifact              owner
    ----------------      -----------------
    intent policy       UPF owner
    implementation      CAD owner
    verification        integration lead
    
    Escapes happen when ownership is implicit.

    Subpages in this topic

    Each topic is taught across mechanism, inputs/outputs, reports, debug, worked example, pitfalls, interview, checklist, theory, design space, expanded case study, walkthrough, comparison matrix, software view, and silicon impact.

    Key takeaways

    • Always name the transition context for every low-power metric.

    • Bind each policy decision to a specific owner and artifact.

    • Re-run LP simulation, formal, and implementation checks after changes.

    Common pitfalls

    • Treating static pass reports as transition closure.

    • Fixing symptoms without checking policy binding and sequence order.

    • Shipping with ambiguous ownership on open LP violations.

    Low-power deep dive

    Power intent must be explicit, reviewable, and tool-consistent from day one.

    Concept diagram

    Diagram
    POWER INTENT FLOW
    
    architecture -> UPF objects -> tool binding -> verification evidence

    Metric graph

    Diagram
    INTENT QUALITY
    
    bound policies      ████████████ high
    stale references    ███          medium risk
    missing states      ██           high risk

    Reports and artifacts

    • PST report

    • domain map

    • UPF lint

    • policy binding summary

    Mini case study

    One missing PST entry blocked legal retention mode and caused false debug loops.

    Debug branches

    • Check legal state table first

    • Audit policy binding IDs

    • Freeze UPF revision tags

    Senior review question

    Ask: what transition evidence proves this topic is closed, and which owner signs it?

    Key takeaways

    • State transition context must accompany every low-power metric claim.

    • Intent changes require simulation, formal, and implementation re-validation.

    Common pitfalls

    • Comparing results from mismatched UPF revisions.

    • Assuming static checks replace transition validation.

    • Shipping with aged waivers and unclear ownership.

    Execution drill pack 1

    Use this pack to rehearse low-power closure on low-power/power-intent-fundamentals/upf-object-model: transition framing, policy ownership, implementation evidence, and release confidence.

    Transition checklist

    • State transition explicitly named with legal source/target states.

    • Crossing and domain ownership are mapped and agreed.

    • Policy controls are traced to always-on source logic.

    • Waveform bookmarks align controls with state timestamps.

    Review prompts

    1. Which policy object is first to deviate from intent?

    2. Which owner can apply the smallest reversible fix?

    3. What regression matrix proves no collateral damage?

    4. Which waiver conditions would still block release?

    Evidence capsule

    Diagram
    LP EVIDENCE CAPSULE 1
    
    PATH: low-power/power-intent-fundamentals/upf-object-model
    STATE WINDOW: <from -> to>
    POLICY OBJECT: <isolation / retention / shifter / switch>
    OWNER: <name>
    PRIMARY ARTIFACT: <report/waveform/formal result>
    RELEASE DECISION: <close / bounded waiver / escalate>

    Execution drill pack 2

    Use this pack to rehearse low-power closure on low-power/power-intent-fundamentals/upf-object-model: transition framing, policy ownership, implementation evidence, and release confidence.

    Transition checklist

    • State transition explicitly named with legal source/target states.

    • Crossing and domain ownership are mapped and agreed.

    • Policy controls are traced to always-on source logic.

    • Waveform bookmarks align controls with state timestamps.

    Review prompts

    1. Which policy object is first to deviate from intent?

    2. Which owner can apply the smallest reversible fix?

    3. What regression matrix proves no collateral damage?

    4. Which waiver conditions would still block release?

    Evidence capsule

    Diagram
    LP EVIDENCE CAPSULE 2
    
    PATH: low-power/power-intent-fundamentals/upf-object-model
    STATE WINDOW: <from -> to>
    POLICY OBJECT: <isolation / retention / shifter / switch>
    OWNER: <name>
    PRIMARY ARTIFACT: <report/waveform/formal result>
    RELEASE DECISION: <close / bounded waiver / escalate>

    Execution drill pack 3

    Use this pack to rehearse low-power closure on low-power/power-intent-fundamentals/upf-object-model: transition framing, policy ownership, implementation evidence, and release confidence.

    Transition checklist

    • State transition explicitly named with legal source/target states.

    • Crossing and domain ownership are mapped and agreed.

    • Policy controls are traced to always-on source logic.

    • Waveform bookmarks align controls with state timestamps.

    Review prompts

    1. Which policy object is first to deviate from intent?

    2. Which owner can apply the smallest reversible fix?

    3. What regression matrix proves no collateral damage?

    4. Which waiver conditions would still block release?

    Evidence capsule

    Diagram
    LP EVIDENCE CAPSULE 3
    
    PATH: low-power/power-intent-fundamentals/upf-object-model
    STATE WINDOW: <from -> to>
    POLICY OBJECT: <isolation / retention / shifter / switch>
    OWNER: <name>
    PRIMARY ARTIFACT: <report/waveform/formal result>
    RELEASE DECISION: <close / bounded waiver / escalate>

    Execution drill pack 4

    Use this pack to rehearse low-power closure on low-power/power-intent-fundamentals/upf-object-model: transition framing, policy ownership, implementation evidence, and release confidence.

    Transition checklist

    • State transition explicitly named with legal source/target states.

    • Crossing and domain ownership are mapped and agreed.

    • Policy controls are traced to always-on source logic.

    • Waveform bookmarks align controls with state timestamps.

    Review prompts

    1. Which policy object is first to deviate from intent?

    2. Which owner can apply the smallest reversible fix?

    3. What regression matrix proves no collateral damage?

    4. Which waiver conditions would still block release?

    Evidence capsule

    Diagram
    LP EVIDENCE CAPSULE 4
    
    PATH: low-power/power-intent-fundamentals/upf-object-model
    STATE WINDOW: <from -> to>
    POLICY OBJECT: <isolation / retention / shifter / switch>
    OWNER: <name>
    PRIMARY ARTIFACT: <report/waveform/formal result>
    RELEASE DECISION: <close / bounded waiver / escalate>

    Execution drill pack 5

    Use this pack to rehearse low-power closure on low-power/power-intent-fundamentals/upf-object-model: transition framing, policy ownership, implementation evidence, and release confidence.

    Transition checklist

    • State transition explicitly named with legal source/target states.

    • Crossing and domain ownership are mapped and agreed.

    • Policy controls are traced to always-on source logic.

    • Waveform bookmarks align controls with state timestamps.

    Review prompts

    1. Which policy object is first to deviate from intent?

    2. Which owner can apply the smallest reversible fix?

    3. What regression matrix proves no collateral damage?

    4. Which waiver conditions would still block release?

    Evidence capsule

    Diagram
    LP EVIDENCE CAPSULE 5
    
    PATH: low-power/power-intent-fundamentals/upf-object-model
    STATE WINDOW: <from -> to>
    POLICY OBJECT: <isolation / retention / shifter / switch>
    OWNER: <name>
    PRIMARY ARTIFACT: <report/waveform/formal result>
    RELEASE DECISION: <close / bounded waiver / escalate>

    Execution drill pack 6

    Use this pack to rehearse low-power closure on low-power/power-intent-fundamentals/upf-object-model: transition framing, policy ownership, implementation evidence, and release confidence.

    Transition checklist

    • State transition explicitly named with legal source/target states.

    • Crossing and domain ownership are mapped and agreed.

    • Policy controls are traced to always-on source logic.

    • Waveform bookmarks align controls with state timestamps.

    Review prompts

    1. Which policy object is first to deviate from intent?

    2. Which owner can apply the smallest reversible fix?

    3. What regression matrix proves no collateral damage?

    4. Which waiver conditions would still block release?

    Evidence capsule

    Diagram
    LP EVIDENCE CAPSULE 6
    
    PATH: low-power/power-intent-fundamentals/upf-object-model
    STATE WINDOW: <from -> to>
    POLICY OBJECT: <isolation / retention / shifter / switch>
    OWNER: <name>
    PRIMARY ARTIFACT: <report/waveform/formal result>
    RELEASE DECISION: <close / bounded waiver / escalate>

    Execution drill pack 7

    Use this pack to rehearse low-power closure on low-power/power-intent-fundamentals/upf-object-model: transition framing, policy ownership, implementation evidence, and release confidence.

    Transition checklist

    • State transition explicitly named with legal source/target states.

    • Crossing and domain ownership are mapped and agreed.

    • Policy controls are traced to always-on source logic.

    • Waveform bookmarks align controls with state timestamps.

    Review prompts

    1. Which policy object is first to deviate from intent?

    2. Which owner can apply the smallest reversible fix?

    3. What regression matrix proves no collateral damage?

    4. Which waiver conditions would still block release?

    Evidence capsule

    Diagram
    LP EVIDENCE CAPSULE 7
    
    PATH: low-power/power-intent-fundamentals/upf-object-model
    STATE WINDOW: <from -> to>
    POLICY OBJECT: <isolation / retention / shifter / switch>
    OWNER: <name>
    PRIMARY ARTIFACT: <report/waveform/formal result>
    RELEASE DECISION: <close / bounded waiver / escalate>
    PreviousNext: UPF Object Model: Mechanism

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    See also

    • Supply Sets & Power States
    • Power Domain Basics
    • CPF vs UPF