4-Lane 4-Port

PCI Express® Switch

®

89HPES4T4

Data Sheet

The 89HPES4T4 is a member of IDT’s PRECISE™ family of PCI

Express switching solutions. The PES4T4 is a 4-lane, 4-port peripheral

chip that performs PCI Express Base switching. It provides connectivity

and switching functions between a PCI Express upstream port and up to

four downstream ports and supports switching between downstream

ports.

Device Overview



Features



High Performance PCI Express Switch

– Four 2.5 Gbps PCI Express lanes

– Four switch ports

– x1 Upstream port

– Three x1 Downstream ports

– Low latency cut-through switch architecture

– Support for Max payload sizes up to 256 bytes

– One virtual channel

– Eight traffic classes

– PCI Express Base Specification Revision 1.1 compliant

Flexible Architecture with Numerous Configuration Options

– Automatic lane reversal on all ports

– Automatic polarity inversion on all lanes

– Ability to load device configuration from serial EEPROM

Legacy Support

– PCI compatible INTx emulation

– Bus locking



Highly Integrated Solution

– Requires no external components

– Incorporates on-chip internal memory for packet buffering and

queueing

– Integrates four 2.5 Gbps embedded SerDes with 8B/10B

encoder/decoder (no separate transceivers needed)

Reliability, Availability, and Serviceability (RAS) Features

– Internal end-to-end parity protection on all TLPs ensures data

integrity even in systems that do not implement end-to-end

CRC (ECRC)

– Supports ECRC and Advanced Error Reporting

– Supports PCI Express Native Hot-Plug, Hot-Swap capable I/O

– Compatible with Hot-Plug I/O expanders used on PC mother-

boards

Power Management

– Utilizes advanced low-power design techniques to achieve low

typical power consumption

– Supports PCI Power Management Interface specification (PCI-

PM 1.2)

– Unused SerDes are disabled.

– Supports Advanced Configuration and Power Interface Speci-

fication, Revision 2.0 (ACPI) supporting active link state

Testability and Debug Features

– Built in Pseudo-Random Bit Stream (PRBS) generator

– Numerous SerDes test modes

– Ability to bypass link training and force any link into any mode

– Provides statistics and performance counters

Block Diagram

4-Port Switch Core / 4 PCI Express Lanes

Frame Buffer

Route Table

Port

Arbitration

Scheduler

Transaction Layer

Data Link Layer

Transaction Layer

Data Link Layer

Transaction Layer

Data Link Layer

Transaction Layer

Data Link Layer

Mux / Demux

Phy

Logical

Layer

Mux / Demux

Phy

Logical

Layer

Mux / Demux

Phy

Logical

Layer

Mux / Demux

Phy

Logical

Layer

SerDes

(Port 0)

(Port 2)

(Port 3)

(Port 4)

Figure 1 Internal Block Diagram

IDT and the IDT logo are registered trademarks of Integrated Device Technology, Inc.

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

2014 Integrated Device Technology, Inc.

June 12, 2014

IDT 89HPES4T4 Data Sheet



5 General Purpose Input/Output Pins

– Each pin may be individually configured as an input or output

– Each pin may be individually configured as an interrupt input

– Each pin has a selectable alternate function

Option A Package: 13mm x 13mm 144-ball BGA with 1mm ball spacing

Option B Package: 10mm x 10mm 132-ball QFN with 1mm ball spacing

Product Description

Utilizing standard PCI Express interconnect, the PES4T4 provides the most efficient fan-out solution for applications requiring x1 connectivity, low

latency, and simple board layout with a minimum number of board layers. Each lane provides 2.5 Gbps of bandwidth in both directions and is fully

compliant with PCI Express Base specification 1.1.

The PES4T4 is based on a flexible and efficient layered architecture. The PCI Express layer consists of SerDes, Physical, Data Link and Transac-

tion layers in compliance with PCI Express Base specification Revision 1.1. The PES4T4 can operate either as a store and forward or cut-through

switch and is designed to switch memory and I/O transactions. It supports eight Traffic Classes (TCs) and one Virtual Channel (VC) with sophisticated

resource management to allow efficient switching for applications requiring additional narrow port connectivity and also some high-end connectivity.

Processor

North

Bridge

Memory

South

Bridge

x1

PES4T4

x1

GE

LOM

x1

GE

LOM

x1

1394

Figure 2 I/O Expansion Application

SMBus Interface

The PES4T4 contains an SMBus master interface. This master interface allows the default configuration register values of the PES4T4 to be over-

ridden following a reset with values programmed in an external serial EEPROM. The master interface is also used by an external Hot-Plug I/O

expander. Two pins make up the SMBus master interface. These pins consist of an SMBus clock pin and an SMBus data pin.

Hot-Plug Interface

The PES4T4 supports PCI Express Hot-Plug on each downstream port. To reduce the number of pins required on the device, the PES4T4 utilizes

an external I/O expander, such as that used on PC motherboards, connected to the SMBus master interface. Following reset and configuration, when-

ever the state of a Hot-Plug output needs to be modified, the PES4T4 generates an SMBus transaction to the I/O expander with the new value of all of

the outputs. Whenever a Hot-Plug input changes, the I/O expander generates an interrupt which is received on the IOEXPINTN input pin (alternate

function of GPIO) of the PES4T4. In response to an I/O expander interrupt, the PES4T4 generates an SMBus transaction to read the state of all of the

Hot-Plug inputs from the I/O expander.

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June 12, 2014

IDT 89HPES4T4 Data Sheet

General Purpose Input/Output

The PES4T4 provides 5 General Purpose Input/Output (GPIO) pins that may be used by the system designer as bit I/O ports. Each GPIO pin may

be configured independently as an input or output through software control, and some GPIO pins are shared with another on-chip functions. These

alternate functions may be enabled via software or serial configuration EEPROM.

Pin Description

The following tables lists the functions of the pins provided on the PES4T4. Some of the functions listed may be multiplexed onto the same pin. The

active polarity of a signal is defined using a suffix. Signals ending with an “N” are defined as being active, or asserted, when at a logic zero (low) level.

All other signals (including clocks, buses, and select lines) will be interpreted as being active, or asserted, when at a logic one (high) level.

Signal

PE0RP[0]

PE0RN[0]

PE0TP[0]

PE0TN[0]

PE2RP[0]

PE2RN[0]

PE2TP[0]

PE2TN[0]

PE3RP[0]

PE3RN[0]

PE3TP[0]

PE3TN[0]

PE4RP[0]

PE4RN[0]

PE4TP[0]

PE4TN[0]

PEREFCLKP

PEREFCLKN

Type

I

O

I

O

I

O

I

O

I

Name/Description

PCI Express Port 0 Serial Data Receive.

Differential PCI Express receive

pair for port 0.

PCI Express Port 0 Serial Data Transmit.

Differential PCI Express trans-

mit pair for port 0.

PCI Express Port 2 Serial Data Receive.

Differential PCI Express receive

pair for port 2.

PCI Express Port 2 Serial Data Transmit.

Differential PCI Express trans-

mit pair for port 2.

PCI Express Port 3 Serial Data Receive.

Differential PCI Express receive

pair for port 3.

PCI Express Port 3 Serial Data Transmit.

Differential PCI Express trans-

mit pair for port 3.

PCI Express Port 4 Serial Data Receive.

Differential PCI Express receive

pair for port 4.

PCI Express Port 4 Serial Data Transmit.

Differential PCI Express trans-

mit pair for port 4.

PCI Express Reference Clock.

Differential reference clock pair input. This

clock is used as the reference clock by on-chip PLLs to generate the clocks

required for the system logic and on-chip SerDes.

Table 1 PCI Express Interface Pins

Signal

MSMBCLK

MSMBDAT

Type

I/O

Name/Description

Master SMBus Clock.

This bidirectional signal is used to synchronize

transfers on the master SMBus.

Master SMBus Data.

This bidirectional signal is used for data on the mas-

ter SMBus.

Table 2 SMBus Interface Pins

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June 12, 2014

IDT 89HPES4T4 Data Sheet

Signal

GPIO[0]

Type

I/O

Name/Description

General Purpose I/O.