On 24/03/2023 06:16, Hao Zhang wrote:
Add documentation for Coresight Dummy Trace under trace/coresight.
Signed-off-by: Hao Zhang quic_hazha@quicinc.com
.../trace/coresight/coresight-dummy.rst | 58 +++++++++++++++++++ 1 file changed, 58 insertions(+) create mode 100644 Documentation/trace/coresight/coresight-dummy.rst
diff --git a/Documentation/trace/coresight/coresight-dummy.rst b/Documentation/trace/coresight/coresight-dummy.rst new file mode 100644 index 000000000000..819cabab8623 --- /dev/null +++ b/Documentation/trace/coresight/coresight-dummy.rst @@ -0,0 +1,58 @@ +.. SPDX-License-Identifier: GPL-2.0
+============================= +Coresight Dummy Trace Module +=============================
- :Author: Hao Zhang quic_hazha@quicinc.com
- :Date: March 2023
+Introduction +---------------------------
+Coresight Dummy Trace Module is for the specific devices that HLOS don't
Please do not use cryptic abbreviations, please use "kernel"
+have permission to access or configure.
Such as Coresight sink EUD, some
+TPDMs etc.
Say "e.g., CoreSight TPDMs on Qualcomm platforms.:
So there need driver to register dummy devices as Coresight
+devices.
Add:
"It may also be used to define components that may not have any programming interfaces (e.g, static links), so that paths can be established in the driver. "
Provide Coresight API for dummy device operations, such as
+enabling and disabling dummy devices. Build the Coresight path for dummy +sink or dummy source for debugging.
I think the following content may not be needed as they are part of the standard source/sink type devices, nothing specific to dummy devices.
--- vvvvv ---
+Sysfs files and directories +---------------------------
+Root: ``/sys/bus/coresight/devices/dummy<N>``
+----
+:File: ``enable_source`` (RW) +:Notes:
- = 0 : disable the datasets of dummy source.
+:Syntax:
- ``echo 1 > enable_source``
+----
+:File: ``enable_sink`` (RW) +:Notes:
- = 0 : disable the datasets of dummy sink.
+:Syntax:
- ``echo 1 > enable_sink``
+----
--- You may remove the above ^^^ ----
+Config details +---------------------------
+There are two types of nodes, dummy sink and dummy source. The nodes +should be observed at the coresight path +"/sys/bus/coresight/devices". +e.g. +/sys/bus/coresight/devices # ls -l | grep dummy +dummy0 -> ../../../devices/platform/soc@0/soc@0:dummy_source/dummy0 +dummy1 -> ../../../devices/platform/soc@0/soc@0:dummy_sink/dummy1
Suzuki