220.127.116.11. Function Level Reset (FLR)
Use the FLR interface to reset individual SR-IOV functions. The PCIe* Hard IP supports FLR for both PFs and VFs. If the FLR is for a specific VF, the received packets for that VF are no longer valid. The flr_* interface signals are provided to the application interface for this purpose. When the flr_rcvd* signal is asserted, it indicates that an FLR is received for a particular PF/VF. Application logic needs to perform its FLR routine and send the completion status back on the flr_completed* interface. The Hard IP will wait for the flr_completed* status to re-enable the VF. Prior to that event, the Hard IP will respond to all transactions to the function that is reset by the FLR with completions with an Unsupported Request (UR) status.
The following figure shows the timing diagram for an FLR event targeting a PF (PF[n] in this example):
Here is the timing diagram for an FLR event targeting a VF: