Some HW has static trace id which cannot be changed via software programming. For this case, configure the trace id in device tree with "trace-id = <xxx>", and call coresight_trace_id_reserve_system_id in device probe function. The id will be reserved for the HW all the time if the device is probed. Mao Jinlong (3): dt-bindings: arm: Add trace-id for coresight dummy source coresight: Add reserve trace id support coresight: dummy: Add reserve atid support for dummy source .../sysfs-bus-coresight-devices-dummy-source | 15 +++++ .../arm/arm,coresight-dummy-source.yaml | 6 ++ drivers/hwtracing/coresight/coresight-dummy.c | 56 +++++++++++++++++-- .../hwtracing/coresight/coresight-platform.c | 26 +++++++++ .../hwtracing/coresight/coresight-trace-id.c | 24 ++++++++ .../hwtracing/coresight/coresight-trace-id.h | 11 ++++ include/linux/coresight.h | 1 + 7 files changed, 135 insertions(+), 4 deletions(-) create mode 100644 Documentation/ABI/testing/sysfs-bus-coresight-devices-dummy-source -- 2.41.0