33 lines
1.1 KiB
ReStructuredText
33 lines
1.1 KiB
ReStructuredText
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.. SPDX-License-Identifier: GPL-2.0
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=============================
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Coresight Dummy Trace Module
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=============================
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:Author: Hao Zhang <quic_hazha@quicinc.com>
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:Date: June 2023
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Introduction
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------------
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The Coresight dummy trace module is for the specific devices that kernel don't
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have permission to access or configure, e.g., CoreSight TPDMs on Qualcomm
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platforms. For these devices, a dummy driver is needed to register them as
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Coresight devices. The module may also be used to define components that may
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not have any programming interfaces, so that paths can be created in the driver.
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It provides Coresight API for operations on dummy devices, such as enabling and
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disabling them. It also provides the Coresight dummy sink/source paths for
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debugging.
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Config details
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--------------
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There are two types of nodes, dummy sink and dummy source. These nodes
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are available at ``/sys/bus/coresight/devices``.
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Example output::
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$ ls -l /sys/bus/coresight/devices | grep dummy
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dummy_sink0 -> ../../../devices/platform/soc@0/soc@0:sink/dummy_sink0
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dummy_source0 -> ../../../devices/platform/soc@0/soc@0:source/dummy_source0
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