Transaction layer protocol (tlp) details, Supported message types – Altera IP Compiler for PCI Express User Manual

Page 177

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August 2014

Altera Corporation

IP Compiler for PCI Express User Guide

8. Transaction Layer Protocol (TLP)

Details

This chapter provides detailed information about the IP Compiler for PCI Express
TLP handling. It includes the following sections:

Supported Message Types

Transaction Layer Routing Rules

Receive Buffer Reordering

Supported Message Types

Table 8–1

describes the message types supported by the IP core.

Table 8–1. Supported Message Types (Part 1 of 3)

(Note 1)

Message

Root

Port

Endpoint

Generated by

Comments

App

Layer

Core

Core

(with AL

input)

INTX Mechanism Messages

For endpoints, only INTA messages are
generated.

Assert_INTA

Receive

Transmit

No

Yes

No

For root port, legacy interrupts are translated
into TLPs of type Message Interrupt which
triggers the int_status[3:0] signals to the
application layer.:

int_status[0]

: Interrupt signal A

int_status[1]

: Interrupt signal B

int_status[2]

: Interrupt signal C

int_status[3]

: Interrupt signal D

Assert_INTB

Receive

Transmit

No

No

No

Assert_INTC

Receive

Transmit

No

No

No

Assert_INTD

Receive

Transmit

No

No

No

Deassert_INTA

Receive

Transmit

No

Yes

No

Deassert_INTB

Receive

Transmit

No

No

No

Deassert_INTC

Receive

Transmit

No

No

No

Deassert_INTD

Receive

Transmit

No

No

No

Power Management Messages

PM_Active_State_Nak

Transmit

Receive

No

Yes

No

PM_PME

Receive

Transmit

No

No

Yes

PME_Turn_Off

Transmit

Receive

No

No

Yes

The pme_to_cr signal sends and acknowledges
this message:

Root Port: When pme_to_cr is asserted, the
Root Port sends the PME_turn_off message.

Endpoint: When pme_to_cr is asserted to
acknowledge the PME_turn_off message by
sending pme_to_ack to the root port.

PME_TO_Ack

Receive

Transmit

No

No

Yes

August 2014
<edit Part Number variable in chapter>

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