82598EB Datasheet, PDF (529/596 Pages) Intel Corporation – Intel® 82598EB 10 Gigabit Ethernet Controller Datasheet

Intel^® 82598EB 10 GbE Controller - Resets
2. Enabled - the channel passes any traffic from the MC (that matched the source MAC address filters)
to the network.
Note: The default state is disabled.
The NC filters pass-through packets according to their source MAC address. The NC tries to
match that source MAC address to one of the MAC addresses configured by the Set MAC
Address command. As a result, the MC should enable network transmit only after configuring
the MAC address.
It is recommended that the MC complete all filtering configuration (especially MAC addresses)
before enabling the network transmit.
This feature can be used for fail-over scenarios. See Section 5.4.5.3.
5.4.3.6 Asynchronous Event Notifications
The asynchronous event notifications are unsolicited messages sent from the NC to the MC to report
status changes (such as link change, OS state change, etc.).
Recommendations:
• The MC firmware designer should use AENs. To do so, the designer must take into account the
possibility that a NC-SI response frame (such as a frame with the NC-SI EtherType), arrives out-
of-context (not immediately after a command, but rather after an out-of-context AEN).
• To enable AENs, the MC should first query which AENs are supported, using the Get Capabilities
command, then enable desired AEN(s) using the Enable AEN command, and only then enable the
channel using the Enable Channel command.
5.4.3.7 Querying Active Parameters
The MC can use the Get Parameters command to query the current status of the operational
parameters.
5.4.4 Resets
In NC-SI there are two types of resets defined:
1. Synchronous entry into the initial state.
2. Asynchronous entry into the initial state.
Recommendations:
• It is very important that the MC firmware designer keep in mind that following any type of reset,
all configurations are considered as lost and thus the MC must re-configure everything.
• As an asynchronous entry into the initial state might not be reported and/or explicitly noticed, the
MC should periodically poll the NC with NC-SI commands (such as Get Version ID, Get
Parameters, etc.) to verify that the channel is not in the initial state. Should the NC channel
respond to the command with a Clear Initial State Command Expected reason code - The MC
should consider the channel (and most probably the entire NC package) as if it underwent a
(possibly unexpected) reset event. Thus, the MC should re-configure the NC. See the NC-SI
specification section on Detecting Pass-through Traffic Interruption.
• The Intel recommended polling interval is 2-3 seconds.
For exact details on the resets, refer to NC-SI specification.
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