Intel® IXP400 Software

Access-Layer Components: ATM Driver Access (IxAtmdAcc) API

These statistics include the number of cells received, the number of cells receive with an incorrect cell size, the number of cells containing parity errors, the number of cells containing HEC errors, and the number of idle cells received.

Provides an interface to use either a threshold mechanism — which allows the client actions to be driven by events — or a polling mechanism — through which the client decides where and when to invoke the functions of the interface.

Supports fast-path-exception packet processing.

Supports use in a complete user environment, a complete-interrupt environment, or a mixture of both.

This is done by providing the control over the Rx and TxDone dispatch functions and transmit and replenish functions. The user may trigger them from interrupts, or poll them, or both, assuming an exclusion mechanism is provided as needed.

The ixAtmdAcc component communicates with the NPEs’ ATM-over-UTOPIA component through entries placed on Queue Manager queues, IXP_BUFs, and associated descriptors — located in external memory and through the message bus interface.

4.4Configuration Services

IxAtmdAcc supports three configuration services:

UTOPIA port configuration

ATM traffic shaping

VC configuration

4.4.1UTOPIA Port-Configuration Service

The UTOPIA interface is the IXP4XX product line and IXC1100 control plane processors’ interface by which ATM cells are sent to and received from external PHYs. In order to configure the UTOPIA interface, IxAtmdAcc provides an interface that allows a configuration structure to be sent to and/or retrieved from the UTOPIA interface.

IxAtmdAcc provides the interface to configure the hardware and enable/disable traffic on a per- port basis.

4.4.2ATM Traffic-Shaping Services

An ATM scheduling entity provides a mechanism where VC traffic on a port is shaped in accordance with its traffic parameters. IxAtmdAcc does not itself provide such a traffic-shaping service, but can be used in conjunction with external scheduling services.

The scheduler registration interface allows registration of ATM traffic-shaping entities on a per- port basis. These entities, or proxies thereof, are expected to support the following callbacks on their API:

Function to exchange VC identifiers.

A VC identifier identifies a port, VPI, and VCI and is usually specific to layer interface. IxAtmdAcc has an identifier known as a connId and the scheduling entity is expected to have

Programmer’s Guide

IXP400 Software Version 2.0

April 2005

 

Document Number: 252539, Revision: 007

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Intel IXP400 manual Configuration Services, Utopia Port-Configuration Service, ATM Traffic-Shaping Services