PCIe Switch for USB4 Hubs, Hosts and Devices

Overview

Rambus PCIe Multi-port Switch for USB4 is a customizable, embedded Switch for PCI Express (PCIe) designed for implementations in USB4 devices. A fully configurable fanout switch, it provides one upstream port and up to 31 downstream ports. Rambus PCIe Multi-port Switch for USB4 enables designers to support tunneling of PCIe traffic in USB4 Hubs as mandated by the USB4 specification, and is also an ideal addition to USB4 Devices or Hosts for attaching internal or external PCIe devices. By implementing internal PCIe devices, designers can differentiate their USB4 ICs while reducing latency and power consumption. Rambus PCIe Multi-port Switch for USB4 provides a flexible, scalable and configurable PCIe switching solution for USB4 Hubs, Hosts and Devices.

Key Features

  • PCI Express Interfaces (upstream and downstream ports)
    • Designed to the USB4 Specification v1.0
    • Follows PCIe 1.0 protocol, but can operate at any compatible speed
    • 1 upstream port, up to 31 downstream ports
    • Supports PCIe Base Revision 5.0, backward compatible down to 3.1
    • Supports PHY Interface for PCIe (PIPE) 5.x
    • Single Virtual Channel (VC) implementation
    • Configurable PIPE interface (8-bit, 16-bit, 32-bit, 64-bit)
    • Configurable Receive and Replay buffer sizes
    • Advanced Error Reporting (AER) supported on each port
    • ECRC generation and check
    • LTR, ACS, FPB, PTM, Hot Plug enabled per USB4 Specification mandate for Hubs
    • Lane reversal supported
    • Switch upstream port supports multiple physical functions
    • Supports for in-the-flow processing
    • ASPM L1, L2
    • Clock and Power gating
    • Peer-to-peer communication between downstream ports
  • Switching Logic
    • PCIe TLP routing: Configuration, Memory Write/Read, I/O and Messages Packets
    • L1 and wake-up events forwarding
    • Peer-to-Peer transactions support between downstream ports
    • Broadcast and Multicast supported
    • Downstream Port Containment (DPC and eDPC) supported
    • Round-Robin arbitration
    • No Packet buffering (cut-through architecture) for reduced latency
    • Built-in advanced data protection including ECRC, LCRC, ECC and Parity
    • Test port available for switch logic monitoring
    • Integrated Clock Domain Crossing to support user-specified frequency in the Switching logic

Benefits

  • Fully transparent design eliminates the need for Host configuration and management software
  • Built-in support for PIPE-attached embedded endpoints (including 64-bit PIPE) for reduced BoM, latency, and power
  • Seamless implementation on ASIC and FPGA with same RTL code base, up to x8 Gen4 per port on FPGA (or x16 Gen3)
  • Lowest latency switching logic on the market (2 clock cycles)
  • Architecture allows insertion of custom processing in-the-flow (i.e. filtering, encryption, etc.)
  • The only solution that supports Hot Plug

Block Diagram

PCIe Switch for USB4 Hubs, Hosts and Devices Block Diagram

Applications

  • HPC,
  • Cloud Computing,
  • AI,
  • Machine Learning,
  • Enterprise,
  • Networking,
  • Automotive,
  • AR/VR,
  • Test and Measurement

Deliverables

  • IP files
    • Verilog RTL source code
    • Libraries for functional simulation
    • Configuration assistant GUI (Wizard)
  • Verification Environment
  • Documentation
  • Reference Design
    • Synthesizable Verilog RTL source code
    • Simulation environment and test scripts
    • Synthesis project & constraint files

Technical Specifications

Foundry, Node
Any
Maturity
In production
Availability
Available
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Semiconductor IP