beautypg.com

Receiver, Receiver –20 – Altera RapidIO MegaCore Function User Manual

Page 66

background image

4–20

Chapter 4: Functional Description

Transport Layer

RapidIO MegaCore Function

August 2014

Altera Corporation

User Guide

Disable Destination ID checking by default

—If you turn on this parameter,

request packets are considered recognized even if the destination ID does not
match the value programmed in the

Base Device ID CSR—Offset: 0x60

. This

feature enables the RapidIO IP core to process multi-cast transactions correctly.
This parameter is turned on in RapidIO Arria 10 variations.

You can also turn on and turn off destination ID checking in the PROMISCUOUS_MODE
field of the Rx Transport Control register at offset 0x10600 (

Table 6–51 on

page 6–24

).

1

The Transport layer is enabled automatically by default, and cannot be disabled.
Beginning with the RapidIO IP core v14.0 release, the RapidIO IP core no longer
supports Physical-layer only instances.

The Transport layer module is divided into receiver and transmitter submodules.

Figure 4–7

shows a block diagram of the Transport layer module.

Receiver

On the receive side, the Transport layer module receives packets from the Physical
layer. Packets travel through the Rx buffer, and any errored packet is eliminated. The
Transport layer module routes the packets to one of the Logical layer modules or to
the Avalon-ST pass-through interface based on the packet's destination ID, format
type (ftype), and target transaction ID (targetTID) header fields. The destination ID
matches only if the transport type (tt) field matches.

Figure 4–7. Transport Layer Block Diagram

Rx

Buffer

Logical Layer

Rx

scheduler

Tx

Transport

Layer

Physical Layer

Avalon-ST

Pass Through