Data Sheet

Ethernet Controller I210 —System Manageability
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Both endpoints (SMBus and PCIe) may be active concurrently. However, pass through traffic may be
transferred only through one of them. If the PCIe endpoint is active, it will be used for pass through
traffic, otherwise, the SMBus endpoint will be used. Section 10.7.2.2 describes the transition between
the two busses.
For each channel (SMBus or PCIe), the I210 should expect MCTP commands from two sources: the bus
owner and the MC. In addition, it should expect pass through traffic through one interface only. Thus it
should be able to process up to five interleaved commands/data. Each source should not interleave
transactions it sends to the I210.
The topology used for MCTP connection is described in Figure 10-9.
Figure 10-9. MCTP Endpoints Topology
10.7.2.1 Detection of MC EID and Physical Address
In order to allow transactions between the MC and the NIC, the bus physical address (SMBus or PCIe)
and the EID of the partner needs to be discovered. The NICs do not try to discover the MC and assume
the MC will initiate the connection. If the NIC is in NC-SI initial state, then the EID and the physical
Port
NC-SI Channel
NC-SI Package
MCTP Endpoint – PCIe
MCTP Endpoint – SMBusSMBus I/F
Function
PCIe Bus I/F