Hard Processor System Technical Reference Manual: Agilex™ 5 SoCs

ID 814346
Date 7/19/2024
Public
Document Table of Contents

13.4.5.2. Packet Tracing, Profiling, Statistics, Alarms, and Error Logs

Packet probes perform both tracing and statistic collection over packets passing through links connected to the probe.

Tracing can be fine-tuned through a filter or a combination of filters. Packets matching filter criteria are sent to the observer (to be forwarded to the ATB bus). Trace alarms can also be raised when packets match filter criteria. Trace alarms are software readable registers on the system interconnect.

Statistics collection is done by setting up counters that track the number of packets matching certain criteria going through a link. Alarms can also be set when a statistic count hits a certain level.

The following table shows how each packet probe is configured.

Table 398.  Probe Configuration
Probe nFilter Filter on Enabled Bytes Payload Tracing nStatistics Counter wStatistics Counter Statistics Counter Alarm Cross Trigger
CCU 2 False False 4 16 True CoreSight
HPS2FPGA 2 False False 4 16 True CoreSight
EMAC 2 False False 4 16 True CoreSight

Packet Filtering

You can set up filters to control how the observation network handles traced packets.

Filters can perform the following tasks:

  • Select which packets the observation network routes to CoreSight
  • Trigger a trace alarm when a packet meets specified criteria

Statistics Collection

To collect packet statistics, you specify packet criteria and set up counters for packets that meet those criteria. You can set up the observation network to trigger an alarm when a counter reaches a specified level.

EMAC Transaction Profiling

A transaction probe is available on the Ethernet MACs. You can use the transaction probe to measure either the transaction latency or the number of pending packets on the EMAC. Data are collected as a histogram.

The EMAC0 transaction probe is configured as shown in the following table.

Table 399.  EMAC0 Transaction Probe Configuration
Parameter Value
Width of counters 10 bits
Available delay thresholds 64, 128, 256, 512
Available pending transaction count thresholds 2, 4, 8
Number of comparators 3

Profiling Transaction Latency

In latency mode (also called delay mode), one of the four delay threshold values can be chosen for each comparator. The threshold values represent the number of clock cycles that a transaction takes from the time the request is issued to the time the response is returned.

Profiling Pending EMAC Transactions

In pending transaction mode, three transaction count threshold values are available for each comparator. The threshold values represent the number of requests pending on the EMACs.

Packet Alarms

You can configure the hardware to trigger a software interrupt on packet alarms.

The following types of alarms are available:

  • Trace alarms: You can examine trace alarms through the system interconnect registers.
  • Statistics alarms

Error Logs

The error probe logs errors on initiators, targets, and firewalls.