1.. SPDX-License-Identifier: GPL-2.0 2 3================================================================= 4The trace performance monitoring and diagnostics aggregator(TPDA) 5================================================================= 6 7 :Author: Jinlong Mao <quic_jinlmao@quicinc.com> 8 :Date: January 2023 9 10Hardware Description 11-------------------- 12 13TPDA - The trace performance monitoring and diagnostics aggregator or 14TPDA in short serves as an arbitration and packetization engine for the 15performance monitoring and diagnostics network specification. 16The primary use case of the TPDA is to provide packetization, funneling 17and timestamping of Monitor data. 18 19 20Sysfs files and directories 21--------------------------- 22Root: ``/sys/bus/coresight/devices/tpda<N>`` 23 24Config details 25--------------------------- 26 27The tpdm and tpda nodes should be observed at the coresight path 28"/sys/bus/coresight/devices". 29e.g. 30/sys/bus/coresight/devices # ls -l | grep tpd 31tpda0 -> ../../../devices/platform/soc@0/6004000.tpda/tpda0 32tpdm0 -> ../../../devices/platform/soc@0/6c08000.mm.tpdm/tpdm0 33 34We can use the commands are similar to the below to validate TPDMs. 35Enable coresight sink first. The port of tpda which is connected to 36the tpdm will be enabled after commands below. 37 38echo 1 > /sys/bus/coresight/devices/tmc_etf0/enable_sink 39echo 1 > /sys/bus/coresight/devices/tpdm0/enable_source 40echo 1 > /sys/bus/coresight/devices/tpdm0/integration_test 41echo 2 > /sys/bus/coresight/devices/tpdm0/integration_test 42 43The test data will be collected in the coresight sink which is enabled. 44If rwp register of the sink is keeping updating when do 45integration_test (by cat tmc_etf0/mgmt/rwp), it means there is data 46generated from TPDM to sink. 47 48There must be a tpda between tpdm and the sink. When there are some 49other trace event hw components in the same HW block with tpdm, tpdm 50and these hw components will connect to the coresight funnel. When 51there is only tpdm trace hw in the HW block, tpdm will connect to 52tpda directly. 53