Intel® IXP400 Software
Access-Layer Components: NPE Message Handler (IxNpeMh) API
Programmer’s Guide IXP400 Software Version 2.0 April 2005
Document Number: 252539, Revision: 007 231
15.7 Dependencies
The IxNpeMh component’s dependencies (as shown in Figure 74) are:
Client software components must use the IxNpeMh component for messages to and from the
NPEs.
The IxNpeMh component must use IxOSAL for error-handling, resource protection, and
registration of ISRs.
15.8 Error Handling
The IxNpeMh component uses IxOSAL to report errors and warnings. Parameters passed to the
IxNpeMh component are error-checked whenever possible. Interface functions of the IxNpeMh
component return a status to the client, indicating success or failure.
The most important error scenarios — when using the IxNpeMh — are:
Failure to send a message if the NPE is unable to accept one.
Failure to receive a message if no suitable callback can be found.
Failure to send a message implies there is some problem with the NPE. Failure to receive a
message means the message will be discarded.
To avoid message loss, clients should ensure that unsolicited callbacks are registered for all
unsolicited message types.
Figure 74. ixNpeMh Component Dependencies
ixOsal
IxNpeMh
Client Software
Component
Client Software
Component
Client Software
Component
B2398-02