The Alveo X3522PV supports the SMBus/I2C interface for out-of-band card management. The server Board Management Controller (BMC) communicates using SMBus to the satellite controller over the PCIe edge connector. For more information on out-band-card management, see Alveo Card Out-of-Band Management Specification for Server BMC.
The satellite controller acts as an I2C bus master and communicates with numerous sensors and voltage regulators on the card. While these I2C interfaces are not accessible from the UltraScale+ device, they are accessible via the satellite controller through the CMS. See Card Management Solution Subsystem Product Guide (PG348) for more information.