2. RapidIO Ports > Packet Trace and Filtering
CPS-1848 User Manual
56
June 2, 2014
Formal Status
This document is confidential and is subject to an NDA.
Integrated Device Technology
The user can change a comparison value or mask (same value) for all ports with a write to a single address. The device
provides an individual enable/disable feature for each comparison value for each port (four values for each of the 18 ports). To
change a comparison value the user must first disable the value for use as a comparison. The user can then change the value
and then re-enable it. While this value is being changed, the port can receive normal traffic and will continue to trace on the
other three values (if enabled).
Note that to change the trace port definition, the trace function must be disabled globally (all values of all ports). Broadcast
trace enable/disable requires a write to only a single address.
2.9.1.3.6
Alert on Trace Match
Each S-RIO port can generate and transmit a port-write maintenance packet when a received packet meets the Trace criteria
of any port. The ability to activate and deactivate this function dynamically is provided on a per-port basis. If enabled, once the
device sends a port-write because of a trace match, it will temporarily disable sending port-writes on subsequent trace
matches until it receives a maintenance write command to re-enable the ability to do so. This functionality is accessible through
the
Port {0..17} Trace Port-Write Reset Register
. This is to prevent a flood of port-writes to the system-level maintenance
processor if a large number of packets is received that match the trace criteria. Note that this disable on trace matches will not
affect the generation of port-writes for any other reason.
disables all IDT maintenance packet port-writes generated by the
device. This bit also applies to port-writes that are generated as a result of trace matches. Trace match based port-writes are
enabled via TRACE_PW_EN in the
Port {0..17} Operations Register
. Standard port-write packet generation is not affected by
this bit.
Each S-RIO port supports a set of counters that increment each time the port receives a packet that matches the Trace criteria.
Each S-RIO port supports a counter for each of the four comparison values. These counters are accessible in the same way
that all other device counters are made accessible. All trace counters are 32 bits.
2.9.1.3.7
Flow Control with Trace Enabled
Each S-RIO port supports S-RIO-defined receiver- and transmitter-controlled flow control when Trace is enabled. If buffer
contention exists at the trace port such that packets which reference the trace port cannot be received, then the packet will not
be received into the switch Input Buffer and an appropriate request for retransmission of the packet is transmitted to the link
partner.
2.9.1.3.8
Errored Packets
Each S-RIO port does not support packet trace for packets that are not acknowledged or are retried at the physical layer, such
as packets with CRC errors and packets that are longer than 276 bytes. Each port supports trace for packets with logical errors
(for example, invalid type, or Maintenance packets that are longer than 20 words) as long as they match the trace criteria.
Trace matching continues, however, regardless of the port’s error state.
Packets that are retried or stomped may still match the trace and/or filter criteria. The associated trace
and filter counters will increment for retried or stomped packets. To limit this impact, use
transmitter-controlled flow control (see
Transmitter- and Receiver-Controlled Flow Control
If a packet can match multiple trace S-RIO ports, only the counter(s) that are associated with the first
completed match or matches are incremented. A match is completed when the remainder of a packet is
compared against zero values in the
Port x Trace y Mask z Registers
. If multiple matches complete at
the same time, only those counters will increment.
