Re: [PATCH v5 1/7] dt-bindings: arm: Add support for Coresight TGU trace

["Rob Herring (Arm)" <robh@kernel.org>]

On Thu, 29 May 2025 16:19:42 +0800, Songwei Chai wrote:
> The Trigger Generation Unit (TGU) is designed to detect patterns or
> sequences within a specific region of the System on Chip (SoC). Once
> configured and activated, it monitors sense inputs and can detect a
> pre-programmed state or sequence across clock cycles, subsequently
> producing a trigger.
> 
>    TGU configuration space
>         offset table
>  x-------------------------x
>  |                         |
>  |                         |
>  |                         |                           Step configuration
>  |                         |                             space layout
>  |   coresight management  |                           x-------------x
>  |        registers        |                     |---> |             |
>  |                         |                     |     |  reserve    |
>  |                         |                     |     |             |
>  |-------------------------|                     |     |-------------|
>  |                         |                     |     | priority[3] |
>  |         step[7]         |<--                  |     |-------------|
>  |-------------------------|   |                 |     | priority[2] |
>  |                         |   |                 |     |-------------|
>  |           ...           |   |Steps region     |     | priority[1] |
>  |                         |   |                 |     |-------------|
>  |-------------------------|   |                 |     | priority[0] |
>  |                         |<--                  |     |-------------|
>  |         step[0]         |-------------------->      |             |
>  |-------------------------|                           |  condition  |
>  |                         |                           |             |
>  |     control and status  |                           x-------------x
>  |           space         |                           |             |
>  x-------------------------x                           |Timer/Counter|
>                                                        |             |
> 						       x-------------x
> TGU Configuration in Hardware
> 
> The TGU provides a step region for user configuration, similar
> to a flow chart. Each step region consists of three register clusters:
> 
> 1.Priority Region: Sets the required signals with priority.
> 2.Condition Region: Defines specific requirements (e.g., signal A
> reaches three times) and the subsequent action once the requirement is
> met.
> 3.Timer/Counter (Optional): Provides timing or counting functionality.
> 
> Add a new coresight-tgu.yaml file to describe the bindings required to
> define the TGU in the device trees.
> 
> Signed-off-by: Songwei Chai <quic_songchai@quicinc.com>
> ---
>  .../bindings/arm/qcom,coresight-tgu.yaml      | 92 +++++++++++++++++++
>  1 file changed, 92 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/arm/qcom,coresight-tgu.yaml
> 

Reviewed-by: Rob Herring (Arm) <robh@kernel.org>