# EE Contract

Status: `Draft`

## Purpose

Define what the Emotion Engine-facing block must provide to the rest of the
system, independent of the eventual core implementation strategy.

## Owns

- R5900 execution core,
- COP0-visible system behavior owned by the EE block,
- FPU/MMI behavior as implemented by the EE-side compute engine,
- exception and interrupt intake on the EE side,
- request generation onto EE-visible memory and I/O space.

## Inputs

- clocks/resets,
- interrupts,
- memory read/write responses,
- DMAC/VIF/VU/GS-visible status signals as needed by software-facing I/O.

## Outputs

- instruction fetches,
- data reads/writes,
- coprocessor-side requests,
- interrupt acknowledge / exception state transitions,
- debug trace events.

## Questions to lock

- Is the EE treated as an imported core behind a wrapper or as locally-owned RTL?
- What minimum COP0/TLB behavior is required for the first BIOS milestone?
- Which FPU edge cases are correctness-critical versus deferrable?

## Allowed early stubs

- fetch-only or reduced decode EE stub for memory-map bring-up,
- reduced exception model for pre-BIOS milestones,
- trace-only execution harness.

## Required debug visibility

- PC stream,
- exception vector entries,
- uncached/cached access origin tags when applicable,
- selected register snapshots around traps and branches.