Commit 32ee00d8 authored by James Clark's avatar James Clark Committed by Suzuki K Poulose
Browse files

Documentation: coresight: Link config options to existing documentation 



In order to document the newly added branch_broadcast option, create a
table that links all of the config option formats to any existing docs.
That way when the branch broadcast docs are expanded they are accessible
from both places.

Signed-off-by: default avatarJames Clark <james.clark@arm.com>
Reviewed-by: default avatarMike Leach <mike.leach@linaro.org>
Signed-off-by: default avatarSuzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20220511144601.2257870-4-james.clark@arm.com
parent bcc5834f

Documentation/trace/coresight/coresight-etm4x-reference.rst

+4 −0
Original line number Diff line number Diff line
@@ -650,6 +650,7 @@ Bit assignments shown below:- 
    parameter is set this value is applied to the currently indexed

    address range.



.. _coresight-branch-broadcast:



**bit (4):**

    ETM_MODE_BB
@@ -657,6 +658,7 @@ Bit assignments shown below:- 
**description:**

    Set to enable branch broadcast if supported in hardware [IDR0].



.. _coresight-cycle-accurate:



**bit (5):**

    ETMv4_MODE_CYCACC
@@ -678,6 +680,7 @@ Bit assignments shown below:- 
**description:**

    Set to enable virtual machine ID tracing if supported [IDR2].



.. _coresight-timestamp:



**bit (11):**

    ETMv4_MODE_TIMESTAMP
@@ -685,6 +688,7 @@ Bit assignments shown below:- 
**description:**

    Set to enable timestamp generation if supported [IDR0].



.. _coresight-return-stack:



**bit (12):**

    ETM_MODE_RETURNSTACK

Documentation/trace/coresight/coresight.rst

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@@ -585,6 +585,45 @@ sort example is from the AutoFDO tutorial (https://gcc.gnu.org/wiki/AutoFDO/Tuto 
	Bubble sorting array of 30000 elements

	5806 ms



Config option formats

~~~~~~~~~~~~~~~~~~~~~



The following strings can be provided between // on the perf command line to enable various options.

They are also listed in the folder /sys/bus/event_source/devices/cs_etm/format/



.. list-table::

   :header-rows: 1



   * - Option

     - Description

   * - branch_broadcast

     - Session local version of the system wide setting:

       :ref:`ETM_MODE_BB <coresight-branch-broadcast>`

   * - contextid

     - See `Tracing PID`_

   * - contextid1

     - See `Tracing PID`_

   * - contextid2

     - See `Tracing PID`_

   * - configid

     - Selection for a custom configuration. This is an implementation detail and not used directly,

       see :ref:`trace/coresight/coresight-config:Using Configurations in perf`

   * - preset

     - Override for parameters in a custom configuration, see

       :ref:`trace/coresight/coresight-config:Using Configurations in perf`

   * - sinkid

     - Hashed version of the string to select a sink, automatically set when using the @ notation.

       This is an internal implementation detail and is not used directly, see `Using perf

       framework`_.

   * - cycacc

     - Session local version of the system wide setting: :ref:`ETMv4_MODE_CYCACC

       <coresight-cycle-accurate>`

   * - retstack

     - Session local version of the system wide setting: :ref:`ETM_MODE_RETURNSTACK

       <coresight-return-stack>`

   * - timestamp

     - Session local version of the system wide setting: :ref:`ETMv4_MODE_TIMESTAMP

       <coresight-timestamp>`



How to use the STM module

-------------------------