Port Data Rate - 2.3 English

Versal Devices Integrated 100G Multirate Ethernet MAC Subsystem Product Guide (PG314)

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2.3 English

The MRMAC architecture is composed of four independent Ethernet ports, each capable of 10/25GE data rate. The port resources can be dynamically combined to produce higher IEEE Ethernet rates, up to an overall bandwidth of 100GE. The ports can be statically configured through the IP wizard or dynamically configured during run-time through the AXI4-Lite interface.

Note: Dynamically reconfiguring the client rates of the MRMAC has clocking implications. Ensure that you understand the details surrounding clocking (see Clocking) and review the Use Cases in the Clocking Use Cases if you intend to take advantage of this capability.

A port data rate is configured using the ctl_data_rate_<N> field (N = 0...3) of each MODE_REG of the port. Values are shown in the following table. All values not listed are reserved.

Table 1. Port Data Rate
Port Configurable Modes (ctl_data_rate_<N>[2:0])
10GE 25GE 40GE 50GE 100GE
0 000 001 010 011 100
1 000 001 N/A N/A N/A
2 000 001 N/A 011 N/A
3 000 001 N/A N/A N/A
  1. N/A denotes that the data rate is not supported by that port. All values not listed in the table are reserved.

Port 0 can be configured to operate at 10GE, 25GE, 40GE, 50GE, or 100GE data rates. However, when operating at 50GE data rate, port 0 consumes the data path resources of port 1, making it unavailable for independent operation. When port 0 is configured for 40GE or 100GE data rate operation, all internal data path resources are consumed. Consequently, ports 1, 2, and 3 are unavailable for independent operation.

Similarly, when port 2 is configured to operate at 50GE data rate, it consumes the data path of port 3, making port 3 unavailable for independent operation. Modes can be mixed-and-matched. For example, the user logic could configure ports 0 and 1 as 10GE and 25GE respectively, and then configure port 2 as a single 50GE client.

A change in the MODE_REG register of any port requires a reset to be issued to that port after configuration is complete.