Merge tag 'coresight-next-v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/coresight/linux into char-misc-next

Suzuki writes:

coresight: Updates for v6.5

CoreSight and hwtracing subsystem updates for v6.5 includes:

 - Fixes to the CTI module reference leaks. This involves,
   redesign of how the helper devices are tracked and CTI
   devices have been converted to helper devices.
 - Fix removal of the trctraceidr file from sysfs for ETMs.
 - Match all ETMv4 instances based on the ETMv4 architected
   registers and the CoreSight Component ID (CID), than having
   to add individual PIDs for CPUs.
 - Add support for Dummy CoreSight source and sink drivers.
 - Add James Clark as Reviewer for the CoreSight kernel drivers
 - Fixes to HiSilicon PCIe Tune and Trace Device driver

Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>

* tag 'coresight-next-v6.5' of git://git.kernel.org/pub/scm/linux/kernel/git/coresight/linux: (27 commits)
  hwtracing: hisi_ptt: Fix potential sleep in atomic context
  hwtracing: hisi_ptt: Advertise PERF_PMU_CAP_NO_EXCLUDE for PTT PMU
  hwtracing: hisi_ptt: Export available filters through sysfs
  hwtracing: hisi_ptt: Add support for dynamically updating the filter list
  hwtracing: hisi_ptt: Factor out filter allocation and release operation
  coresight: dummy: Update type of mode parameter in dummy_{sink,source}_enable()
  Documentation: trace: Add documentation for Coresight Dummy Trace
  dt-bindings: arm: Add support for Coresight dummy trace
  Coresight: Add coresight dummy driver
  MAINTAINERS: coresight: Add James Clark as Reviewer
  coresight: etm4x: Match all ETM4 instances based on DEVARCH and DEVTYPE
  coresight: etm4x: Make etm4_remove_dev() return void
  coresight: etm4x: Fix missing trctraceidr file in sysfs
  coresight: Fix CTI module refcount leak by making it a helper device
  coresight: Enable and disable helper devices adjacent to the path
  coresight: Refactor out buffer allocation function for ETR
  coresight: Make refcount a property of the connection
  coresight: Store in-connections as well as out-connections
  coresight: Simplify connection fixup mechanism
  coresight: Store pointers to connections rather than an array of them
  ...

2 files changed, 41 insertions, 3 deletions

diff --git a/Documentation/trace/coresight/coresight-dummy.rst b/Documentation/trace/coresight/coresight-dummy.rst
new file mode 100644
index 000000000000..eff7c553ee6c
--- /dev/null
+++ b/Documentation/trace/coresight/coresight-dummy.rst
@@ -0,0 +1,32 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+=============================
+Coresight Dummy Trace Module
+=============================
+
+    :Author:   Hao Zhang <quic_hazha@quicinc.com>
+    :Date:     June 2023
+
+Introduction
+------------
+
+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, 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. These nodes
+are available at ``/sys/bus/coresight/devices``.
+
+Example output::
+
+    $ 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
diff --git a/Documentation/trace/hisi-ptt.rst b/Documentation/trace/hisi-ptt.rst
index 4f87d8e21065..989255eb5622 100644
--- a/Documentation/trace/hisi-ptt.rst
+++ b/Documentation/trace/hisi-ptt.rst
@@ -148,14 +148,20 @@ For example, if the desired filter is Endpoint function 0000:01:00.1 the filter
 value will be 0x00101. If the desired filter is Root Port 0000:00:10.0 then
 then filter value is calculated as 0x80001.
 
+The driver also presents every supported Root Port and Requester filter through
+sysfs. Each filter will be an individual file with name of its related PCIe
+device name (domain:bus:device.function). The files of Root Port filters are
+under $(PTT PMU dir)/root_port_filters and files of Requester filters
+are under $(PTT PMU dir)/requester_filters.
+
 Note that multiple Root Ports can be specified at one time, but only one
 Endpoint function can be specified in one trace. Specifying both Root Port
 and function at the same time is not supported. Driver maintains a list of
 available filters and will check the invalid inputs.
 
-Currently the available filters are detected in driver's probe. If the supported
-devices are removed/added after probe, you may need to reload the driver to update
-the filters.
+The available filters will be dynamically updated, which means you will always
+get correct filter information when hotplug events happen, or when you manually
+remove/rescan the devices.
 
 2. Type
 -------