RISC-V Design · All levels

Privilege Levels, Execution Modes, and Delegation Boundaries: Inputs and Outputs

Inputs and Outputs for Privilege Levels, Execution Modes, and Delegation Boundaries.

Inputs and outputs contract

Inputs and Outputs for Privilege Levels, Execution Modes, and Delegation Boundaries is anchored on Privilege-transition latency and number of unauthorized accesses blocked by PMP/page-permission checks per billion instructions.. Convert observations into mechanism-backed decisions with explicit ownership.

diagram

INPUTS
  - workload definition and target KPI
  - architecture profile and enabled extensions
  - compiler/runtime/firmware metadata
  - correctness and security gates

OUTPUTS
  - evidence-backed bottleneck class
  - owner-signed mitigation plan
  - validation matrix with rollback thresholds

Ownership split

diagram

RISC-V OWNERSHIP LAYERS - Privilege Levels, Execution Modes, and Delegation Boundaries

layer                  owner                         closure artifact
--------------------   ----------------------------  -----------------------------
ISA compliance         architecture/spec team        unpriv + priv test evidence
decode/control         front-end RTL owner           decode matrix + assertions
pipeline timing        microarchitecture owner       hazard/perf regression trends
memory + MMU           LSU/MMU owner                 TLB/pagewalk trace checks
privilege/CSR path     firmware + kernel interface   trap/interrupt conformance
vector subsystem       vector RTL + compiler owner   lane-utilization profiles

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