Documentation/trace/coresight/coresight-trbe.rst

Source file repositories/reference/linux-study-clean/Documentation/trace/coresight/coresight-trbe.rst

File Facts

System: Linux kernel
Corpus path: Documentation/trace/coresight/coresight-trbe.rst
Extension: .rst
Size: 1189 bytes
Lines: 39
Domain: Support Tooling And Documentation
Bucket: Documentation
Inferred role: Support Tooling And Documentation: documentation
Status: atlas-only

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

No C-style include directives detected by the generator.

Detected Declarations

No top-level syscall, struct, function, initcall, or export declaration detected by the generator.

Annotated Snippet

.. SPDX-License-Identifier: GPL-2.0

==============================
Trace Buffer Extension (TRBE).
==============================

    :Author:   Anshuman Khandual <anshuman.khandual@arm.com>
    :Date:     November 2020

Hardware Description
--------------------

Trace Buffer Extension (TRBE) is a percpu hardware which captures in system
memory, CPU traces generated from a corresponding percpu tracing unit. This
gets plugged in as a coresight sink device because the corresponding trace
generators (ETE), are plugged in as source device.

The TRBE is not compliant to CoreSight architecture specifications, but is
driven via the CoreSight driver framework to support the ETE (which is
CoreSight compliant) integration.

Sysfs files and directories
---------------------------

The TRBE devices appear on the existing coresight bus alongside the other
coresight devices::

	>$ ls /sys/bus/coresight/devices
	trbe0  trbe1  trbe2 trbe3

The ``trbe<N>`` named TRBEs are associated with a CPU.::

	>$ ls /sys/bus/coresight/devices/trbe0/
        align flag

*Key file items are:-*
   * ``align``: TRBE write pointer alignment
   * ``flag``: TRBE updates memory with access and dirty flags

Annotation

Atlas domain: Support Tooling And Documentation / Documentation.
Implementation status: atlas-only.

Implementation Notes

This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.