Introduction of TPDM DSB subunit DSB subunit is responsible for creating a dataset element, and is also optionally responsible for packing it to fit multiple elements on a single ATB transfer if possible in the configuration. The TPDM Core Datapath requests timestamps be stored by the TPDA and then delivering ATB sized data (depending on ATB width and element size, this could be smaller or larger than a dataset element) to the ATB Mast FSM.
The DSB subunit must be configured prior to enablement. This series adds support for TPDM to configure the configure DSB subunit.
Once this series patches are applied properly, the new tpdm nodes for should be observed at the tpdm path /sys/bus/coresight/devices/tpdm* which supports DSB subunit. e.g. /sys/devices/platform/soc@0/69d0000.tpdm/tpdm0#ls -l | grep dsb -rw-r--r-- 1 root root 4096 Jan 1 00:01 dsb_edge_ctrl -rw-r--r-- 1 root root 4096 Jan 1 00:01 dsb_edge_ctrl_mask -rw-r--r-- 1 root root 4096 Jan 1 00:01 dsb_mode -rw-r--r-- 1 root root 4096 Jan 1 00:01 dsb_patt_mask -rw-r--r-- 1 root root 4096 Jan 1 00:01 dsb_patt_ts -rw-r--r-- 1 root root 4096 Jan 1 00:01 dsb_patt_type -rw-r--r-- 1 root root 4096 Jan 1 00:01 dsb_patt_val -rw-r--r-- 1 root root 4096 Jan 1 00:01 dsb_trig_patt_mask -rw-r--r-- 1 root root 4096 Jan 1 00:01 dsb_trig_patt_val -rw-r--r-- 1 root root 4096 Jan 1 00:01 dsb_trig_ts -rw-r--r-- 1 root root 4096 Jan 1 00:01 dsb_trig_type
We can use the commands are similar to the below to configure the TPDMs which support DSB subunit. Enable coresight sink first. echo 1 > /sys/bus/coresight/devices/tmc_etf0/enable_sink echo 1 > /sys/bus/coresight/devices/tpdm0/reset echo 0x3 0x3 0x1 > /sys/bus/coresight/devices/tpdm0/dsb_edge_ctrl_mask echo 0x6d 0x6d 0 > /sys/bus/coresight/devices/tpdm0/dsb_edge_ctrl echo 1 > /sys/bus/coresight/devices/tpdm0/dsb_patt_ts echo 1 > /sys/bus/coresight/devices/tpdm0/dsb_patt_type echo 0 > /sys/bus/coresight/devices/tpdm0/dsb_trig_ts echo 0 0xFFFFFFFF > /sys/bus/coresight/devices/tpdm0/dsb_patt_mask echo 0 0xFFFFFFFF > /sys/bus/coresight/devices/tpdm0/dsb_trig_patt_val
This series applies to coresight/next https://git.kernel.org/pub/scm/linux/kernel/git/coresight/linux.git?h=next
This patch series depends on patch series "[v12,0/9] Coresight: Add support for TPDM and TPDA" https://patchwork.kernel.org/project/linux-arm-kernel/cover/20220905065357.1...
Tao Zhang (9): dt-bindings: arm: Add support for DSB element coresight-tpda: Add DSB dataset support coresight-tpdm: Initialize DSB subunit configuration coresight-tpdm: Add reset node to TPDM node coresight-tpdm: Add nodes to set trigger timestamp and type coresight-tpdm: Add node to set dsb programming mode coresight-tpdm: Add nodes for dsb element creation coresight-tpdm: Add nodes to configure pattern match output coresight-tpdm: Add nodes for timestamp request
.../bindings/arm/qcom,coresight-tpda.yaml | 9 + drivers/hwtracing/coresight/coresight-tpda.c | 62 ++ drivers/hwtracing/coresight/coresight-tpda.h | 4 + drivers/hwtracing/coresight/coresight-tpdm.c | 625 ++++++++++++++++++++- drivers/hwtracing/coresight/coresight-tpdm.h | 60 ++ 5 files changed, 756 insertions(+), 4 deletions(-)