[PATCH 2/2] coresight: etm4x: docs: Add documentation for 'ts_source' sysfs interface

Mathieu Poirier mathieu.poirier at linaro.org
Mon May 2 09:45:59 PDT 2022


On Fri, Apr 29, 2022 at 01:31:00PM +0100, German Gomez wrote:
> Sync sysfs documentation pages to include the new ts_source (timestamp
> source) interface.
> 
> Signed-off-by: German Gomez <german.gomez at arm.com>
> ---
>  .../ABI/testing/sysfs-bus-coresight-devices-etm4x  |  8 ++++++++
>  .../trace/coresight/coresight-etm4x-reference.rst  | 14 ++++++++++++++
>  2 files changed, 22 insertions(+)
> 
> diff --git a/Documentation/ABI/testing/sysfs-bus-coresight-devices-etm4x b/Documentation/ABI/testing/sysfs-bus-coresight-devices-etm4x
> index 8e53a32f81505..19ac9d6d2f504 100644
> --- a/Documentation/ABI/testing/sysfs-bus-coresight-devices-etm4x
> +++ b/Documentation/ABI/testing/sysfs-bus-coresight-devices-etm4x
> @@ -516,3 +516,11 @@ Contact:	Mathieu Poirier <mathieu.poirier at linaro.org>
>  Description:	(Read) Returns the number of special conditional P1 right-hand keys
>  		that the trace unit can use (0x194).  The value is taken
>  		directly from the HW.
> +
> +What:		/sys/bus/coresight/devices/etm<N>/ts_source
> +Date:		April 2022
> +KernelVersion:	5.18

This would be 5.19 and a (likely) date of July 2022.

> +Contact:	Mathieu Poirier <mathieu.poirier at linaro.org>

Suzuki's name should also be added.

Thanks,
Mathieu

> +Description:	(Read) When FEAT_TRF is implemented, value of TRFCR_ELx.TS used for
> +		trace session. Otherwise -1 indicates an unknown time source. Check
> +		trcidr0.tssize to see if a global timestamp is available.
> diff --git a/Documentation/trace/coresight/coresight-etm4x-reference.rst b/Documentation/trace/coresight/coresight-etm4x-reference.rst
> index d25dfe86af9bf..f016c7c29429b 100644
> --- a/Documentation/trace/coresight/coresight-etm4x-reference.rst
> +++ b/Documentation/trace/coresight/coresight-etm4x-reference.rst
> @@ -71,6 +71,20 @@ the ‘TRC’ prefix.
>  
>  ----
>  
> +:File:            ``ts_source`` (ro)
> +:Trace Registers: None.
> +:Notes:
> +    When FEAT_TRF is implemented, value of TRFCR_ELx.TS used for trace session. Otherwise -1
> +    indicates an unknown time source. Check trcidr0.tssize to see if a global timestamp is
> +    available.
> +
> +:Example:
> +    ``$> cat ts_source``
> +
> +    ``$> 1``
> +
> +----
> +
>  :File:            ``addr_idx`` (rw)
>  :Trace Registers: None.
>  :Notes:
> -- 
> 2.25.1
> 



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