This specification describes Revision A (or Rev A) of the transaction and link layers for ODSA die-to-die (D2D) communication. The transaction and link layers form two parts of a layered architecture using the ODSA bunch-of-wires (BoW) electrical interface and consisting of the following:
- A protocol layer that defines communication between SoC IPs using industry-standard or proprietary protocols
- A transaction layer that translates between protocol transfers or protocol packets defined by a bus protocol and individual transaction streams and that manages the flow control of those individual streams
- A link layer that converts between the individual transaction streams and a single bitstream transmitted between chiplets
- A physical layer that performs the physical transmission of the single bitstream as defined in the BoW PHY Specification
The interfaces between the various layers are defined as follows:
- System Interface – the interface to the SoC as defined by various bus protocols
- Transaction-Link Interface (TLI) – an intermediate interface between the transaction layer and the link layer (this interface is not defined by this specification and is implementation- specific)
- Link-Physical Interface (LPI) – the interface between the link layer and the physical layer based on the slice logic interface as defined in the BoW PHY Specification
- BoW Interface – the electrical interface between the TX and RX PHYs as defined in the BoW PHY Specification
Transaction and Link Layer Specification for Bunch of Wires (BoW) Interfaces – Specification
