IDT CPS-1848, User Manual

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6. Event Management > Event Isolation
CPS-1848 User Manual 156 June 2, 2014
Formal Status This document is confidential and is subject to an NDA.
Integrated Device Technology
6.4.1 Fatal Link Response Timeout Isolation
This isolation function is useful if communication with a link partner can be spontaneously interrupted and the application
cannot continue to operate correctly due to resulting congestion. Possible causes are that the link partner reset itself, or the
link begins to retrain during normal operation.
In the event of errors, the standard RapidIO error recovery function attempts to recover communication. If no response is
received from the link partner, or if the CPS-1848 detects that ackID synchronization has been lost through reception of a
link-response control symbol with an invalid ackID, then it is certain that communication cannot be re-established without
software intervention.
Since software intervention can take significant time during which congestion related failure can occur, this isolation function
allows packets to be discarded.
Discarded a non-maintenance packet
to be transmitted When Port {0..17} Control 1 CSR .PORT_LOCKOUT and OUTPUT_PORT_EN are cleared,
non-maintenance packets routed to that port are dropped. The port sets Port {0..17} Error and
Status CSR .OUTPUT_DROP and Port {0..17} Implementation Specific Error Detect
Register .TX_DROP bit. The port’s Port {0..17} VC0 Switch Crosspoint Buffer Output Packet
Counter Register and Port {0..17} VC0 Transmitted Packets Dropped Counter Register will
increment.
This event is detected when the packet is dropped.
Discarded a received
non-maintenance packet When Port {0..17} Control 1 CSR .PORT_LOCKOUT and INPUT_PORT_EN are cleared,
non-maintenance packets transmitted by the link partner are refused.
The port sets
Port {0..17} Implementation Specific Error Detect Register .RX_DROP. The port’s
Port {0..17} Not Acknowledgements Transmitted Counter Register will increment with every
retransmission attempted by the link partner.
This event is detected when the packet is refused.
Received a packet that references no
route and is dropped The packet is dropped by the receiving port. The port sets the Port {0..17} Implementation
Specific Error Detect Register .RTE_ISSUE. The port’s Port {0..17} VC0 Received Packets
Dropped Counter Register will increment.
When a packet is received whose destID selects a routing table entry with “no route”, that
packet is dropped.
This event is detected when the packet is dropped.
Table 59: Additional Packet Discard Isolation Trigger Functions (Continued)
Event Isolation Behavior