| Message ID | 20230422073714.38844-4-quic_hazha@quicinc.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Add support to configure Coresight Dummy subunit | expand |
On Sat, Apr 22, 2023 at 03:37:14PM +0800, Hao Zhang wrote: > +Introduction > +--------------------------- > + > +Coresight Dummy Trace Module is for the specific devices that kernel > +don't have permission to access or configure, e.g., CoreSight TPDMs > +on Qualcomm platforms. So there need driver to register dummy devices > +as Coresight devices. 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. > + > +Config details > +--------------------------- > + > +There are two types of nodes, dummy sink and dummy source. The nodes > +should be observed at the below coresight path:: > + > + ``/sys/bus/coresight/devices``. > + > +e.g.:: > + > + / $ ls -l /sys/bus/coresight/devices | grep dummy > + dummy0 -> ../../../devices/platform/soc@0/soc@0:dummy_source/dummy0 > + dummy1 -> ../../../devices/platform/soc@0/soc@0:dummy_sink/dummy1 The wording confuses me, so I have to make the improv: ---- >8 ---- diff --git a/Documentation/trace/coresight/coresight-dummy.rst b/Documentation/trace/coresight/coresight-dummy.rst index 7cb59f080c8892..f0a92669288b0c 100644 --- a/Documentation/trace/coresight/coresight-dummy.rst +++ b/Documentation/trace/coresight/coresight-dummy.rst @@ -8,27 +8,25 @@ Coresight Dummy Trace Module :Date: May 2023 Introduction ---------------------------- +------------ -Coresight Dummy Trace Module is for the specific devices that kernel -don't have permission to access or configure, e.g., CoreSight TPDMs -on Qualcomm platforms. So there need driver to register dummy devices -as Coresight devices. 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. +The Coresight dummy trace module is for the specific devices that kernel don't +have permission to access or configure, e.g., CoreSight TPDMs on Qualcomm +platforms. For these devices, a dummy driver is needed to register them as +Coresight devices. The module may also be used to define components that may +not have any programming interfaces (e.g, static links), so that paths can be +created in the driver. It provides Coresight API for operations on dummy +devices, such as enabling and disabling them. It also provides the Coresight +dummy sink/source paths for debugging. Config details ---------------------------- +-------------- -There are two types of nodes, dummy sink and dummy source. The nodes -should be observed at the below coresight path:: +There are two types of nodes, dummy sink and dummy source. These nodes +are available at ``/sys/bus/coresight/devices``. - ``/sys/bus/coresight/devices``. +Example output:: -e.g.:: - - / $ ls -l /sys/bus/coresight/devices | grep dummy + $ ls -l /sys/bus/coresight/devices | grep dummy dummy_sink0 -> ../../../devices/platform/soc@0/soc@0:sink/dummy_sink0 dummy_source0 -> ../../../devices/platform/soc@0/soc@0:source/dummy_source0 Thanks.
Hi Bagas, On 5/10/2023 12:29 PM, Bagas Sanjaya wrote: > On Sat, Apr 22, 2023 at 03:37:14PM +0800, Hao Zhang wrote: >> +Introduction >> +--------------------------- >> + >> +Coresight Dummy Trace Module is for the specific devices that kernel >> +don't have permission to access or configure, e.g., CoreSight TPDMs >> +on Qualcomm platforms. So there need driver to register dummy devices >> +as Coresight devices. 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. >> + >> +Config details >> +--------------------------- >> + >> +There are two types of nodes, dummy sink and dummy source. The nodes >> +should be observed at the below coresight path:: >> + >> + ``/sys/bus/coresight/devices``. >> + >> +e.g.:: >> + >> + / $ ls -l /sys/bus/coresight/devices | grep dummy >> + dummy0 -> ../../../devices/platform/soc@0/soc@0:dummy_source/dummy0 >> + dummy1 -> ../../../devices/platform/soc@0/soc@0:dummy_sink/dummy1 > > The wording confuses me, so I have to make the improv: > > ---- >8 ---- > diff --git a/Documentation/trace/coresight/coresight-dummy.rst b/Documentation/trace/coresight/coresight-dummy.rst > index 7cb59f080c8892..f0a92669288b0c 100644 > --- a/Documentation/trace/coresight/coresight-dummy.rst > +++ b/Documentation/trace/coresight/coresight-dummy.rst > @@ -8,27 +8,25 @@ Coresight Dummy Trace Module > :Date: May 2023 > > Introduction > ---------------------------- > +------------ > > -Coresight Dummy Trace Module is for the specific devices that kernel > -don't have permission to access or configure, e.g., CoreSight TPDMs > -on Qualcomm platforms. So there need driver to register dummy devices > -as Coresight devices. 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. > +The Coresight dummy trace module is for the specific devices that kernel don't > +have permission to access or configure, e.g., CoreSight TPDMs on Qualcomm > +platforms. For these devices, a dummy driver is needed to register them as > +Coresight devices. The module may also be used to define components that may > +not have any programming interfaces (e.g, static links), so that paths can be > +created in the driver. It provides Coresight API for operations on dummy > +devices, such as enabling and disabling them. It also provides the Coresight > +dummy sink/source paths for debugging. > > Config details > ---------------------------- > +-------------- > > -There are two types of nodes, dummy sink and dummy source. The nodes > -should be observed at the below coresight path:: > +There are two types of nodes, dummy sink and dummy source. These nodes > +are available at ``/sys/bus/coresight/devices``. > > - ``/sys/bus/coresight/devices``. > +Example output:: > > -e.g.:: > - > - / $ ls -l /sys/bus/coresight/devices | grep dummy > + $ ls -l /sys/bus/coresight/devices | grep dummy > dummy_sink0 -> ../../../devices/platform/soc@0/soc@0:sink/dummy_sink0 > dummy_source0 -> ../../../devices/platform/soc@0/soc@0:source/dummy_source0 > > Thanks. > Thanks for your review and comments, will update it in the next patch series. Thanks, Hao
diff --git a/Documentation/trace/coresight/coresight-dummy.rst b/Documentation/trace/coresight/coresight-dummy.rst new file mode 100644 index 000000000000..d0f73253f694 --- /dev/null +++ b/Documentation/trace/coresight/coresight-dummy.rst @@ -0,0 +1,34 @@ +.. SPDX-License-Identifier: GPL-2.0 + +============================= +Coresight Dummy Trace Module +============================= + + :Author: Hao Zhang <quic_hazha@quicinc.com> + :Date: April 2023 + +Introduction +--------------------------- + +Coresight Dummy Trace Module is for the specific devices that kernel +don't have permission to access or configure, e.g., CoreSight TPDMs +on Qualcomm platforms. So there need driver to register dummy devices +as Coresight devices. 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. + +Config details +--------------------------- + +There are two types of nodes, dummy sink and dummy source. The nodes +should be observed at the below coresight path:: + + ``/sys/bus/coresight/devices``. + +e.g.:: + + / $ ls -l /sys/bus/coresight/devices | grep dummy + dummy0 -> ../../../devices/platform/soc@0/soc@0:dummy_source/dummy0 + dummy1 -> ../../../devices/platform/soc@0/soc@0:dummy_sink/dummy1
Add documentation for Coresight Dummy Trace under trace/coresight. Signed-off-by: Hao Zhang <quic_hazha@quicinc.com> --- .../trace/coresight/coresight-dummy.rst | 34 +++++++++++++++++++ 1 file changed, 34 insertions(+) create mode 100644 Documentation/trace/coresight/coresight-dummy.rst