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

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 <redacted>
---
 .../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>