diff mbox series

[1/9] dt-bindings: arm: Add support for DSB element

Message ID 1662626705-13097-2-git-send-email-quic_taozha@quicinc.com (mailing list archive)
State Superseded
Headers show
Series Add support to configure TPDM DSB subunit | expand

Commit Message

Tao Zhang Sept. 8, 2022, 8:44 a.m. UTC
Add property "qcom,dsb-elem-size" to support DSB element for TPDA.
Specifies the DSB element size supported by each monitor connected
to the aggregator on each port. Should be specified in pairs (port,
dsb element size).

Signed-off-by: Tao Zhang <quic_taozha@quicinc.com>
---
 Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml | 9 +++++++++
 1 file changed, 9 insertions(+)

Comments

Krzysztof Kozlowski Sept. 8, 2022, 10:54 a.m. UTC | #1
On 08/09/2022 10:44, Tao Zhang wrote:
> Add property "qcom,dsb-elem-size" to support DSB element for TPDA.
> Specifies the DSB element size supported by each monitor connected
> to the aggregator on each port. Should be specified in pairs (port,
> dsb element size).
> 
> Signed-off-by: Tao Zhang <quic_taozha@quicinc.com>
> ---
>  Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml b/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml
> index eb9bfc5..1bb3fdf 100644
> --- a/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml
> +++ b/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml
> @@ -40,6 +40,13 @@ properties:
>      minItems: 1
>      maxItems: 2
>  
> +  qcom,dsb-elem-size:
> +    description: |
> +      Specifies the DSB element size supported by each monitor
> +      connected to the aggregator on each port. Should be specified
> +      in pairs (port, dsb element size).
> +    $ref: /schemas/types.yaml#/definitions/uint32-array

So it is rather uint32-matrix (need to describe the items subschema).
What about maxItems?

Best regards,
Krzysztof
Rob Herring (Arm) Sept. 13, 2022, 12:48 a.m. UTC | #2
On Thu, Sep 08, 2022 at 04:44:57PM +0800, Tao Zhang wrote:
> Add property "qcom,dsb-elem-size" to support DSB element for TPDA.
> Specifies the DSB element size supported by each monitor connected
> to the aggregator on each port. Should be specified in pairs (port,
> dsb element size).

What is DSB?

> 
> Signed-off-by: Tao Zhang <quic_taozha@quicinc.com>
> ---
>  Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml | 9 +++++++++
>  1 file changed, 9 insertions(+)
> 
> diff --git a/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml b/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml
> index eb9bfc5..1bb3fdf 100644
> --- a/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml
> +++ b/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml
> @@ -40,6 +40,13 @@ properties:
>      minItems: 1
>      maxItems: 2
>  
> +  qcom,dsb-elem-size:
> +    description: |
> +      Specifies the DSB element size supported by each monitor
> +      connected to the aggregator on each port. Should be specified
> +      in pairs (port, dsb element size).
> +    $ref: /schemas/types.yaml#/definitions/uint32-array

The binding (not yet upstream) says there is just 1 port (port 0). So 
why do you need more than a single uint32?

Rob
Tao Zhang Sept. 13, 2022, 7 a.m. UTC | #3
在 9/8/2022 6:54 PM, Krzysztof Kozlowski 写道:
> On 08/09/2022 10:44, Tao Zhang wrote:
>> Add property "qcom,dsb-elem-size" to support DSB element for TPDA.
>> Specifies the DSB element size supported by each monitor connected
>> to the aggregator on each port. Should be specified in pairs (port,
>> dsb element size).
>>
>> Signed-off-by: Tao Zhang <quic_taozha@quicinc.com>
>> ---
>>   Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml | 9 +++++++++
>>   1 file changed, 9 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml b/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml
>> index eb9bfc5..1bb3fdf 100644
>> --- a/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml
>> +++ b/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml
>> @@ -40,6 +40,13 @@ properties:
>>       minItems: 1
>>       maxItems: 2
>>   
>> +  qcom,dsb-elem-size:
>> +    description: |
>> +      Specifies the DSB element size supported by each monitor
>> +      connected to the aggregator on each port. Should be specified
>> +      in pairs (port, dsb element size).
>> +    $ref: /schemas/types.yaml#/definitions/uint32-array
> So it is rather uint32-matrix (need to describe the items subschema).
> What about maxItems?
>
> Best regards,
> Krzysztof

Yes, indeed it should be uint32-matrix here. I will update in the next 
release.

The "maxItems" cannot be known explicitly because it depends on how many 
DSB subunit TPDMs are connected to the TPDA input ports.

Usually the number of the items is 1 to several, but there is no limit 
to its maximum value.


Best regards,

Tao
Tao Zhang Sept. 13, 2022, 7:56 a.m. UTC | #4
在 9/13/2022 8:48 AM, Rob Herring 写道:
> On Thu, Sep 08, 2022 at 04:44:57PM +0800, Tao Zhang wrote:
>> Add property "qcom,dsb-elem-size" to support DSB element for TPDA.
>> Specifies the DSB element size supported by each monitor connected
>> to the aggregator on each port. Should be specified in pairs (port,
>> dsb element size).
> What is DSB?

The full name of DSB is "Discrete Single Bit".

The DSB element size supported by different DSB subunit TPDMs is 
different, so TPDA needs to be informed through configuration in device 
tree.

>> Signed-off-by: Tao Zhang <quic_taozha@quicinc.com>
>> ---
>>   Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml | 9 +++++++++
>>   1 file changed, 9 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml b/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml
>> index eb9bfc5..1bb3fdf 100644
>> --- a/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml
>> +++ b/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml
>> @@ -40,6 +40,13 @@ properties:
>>       minItems: 1
>>       maxItems: 2
>>   
>> +  qcom,dsb-elem-size:
>> +    description: |
>> +      Specifies the DSB element size supported by each monitor
>> +      connected to the aggregator on each port. Should be specified
>> +      in pairs (port, dsb element size).
>> +    $ref: /schemas/types.yaml#/definitions/uint32-array
> The binding (not yet upstream) says there is just 1 port (port 0). So
> why do you need more than a single uint32?
>
> Rob

TPDA(Trace, Profiling and Diagnostics Aggregator) is to provide 
packetization, funneling and timestamping of TPDM data.

Multiple monitors are connected to different input ports of TPDA.

  - - - -                 - - - -                 - - - -
| TPDM 0|      | TPDM 1 |     | TPDM 2|
  - - - -                 - - - -                 - - - -
     |                       |                       |
     |_ _ _ _ _ _     |         _ _ _ _  |
                         |   |        |
                         |   |        |
                       ------------------
                      |        TPDA      |
                       ------------------

There may be multiple DSB subunit TPDMs connected to different input 
ports of the same TPDA, so we need to use port here to define the 
distinction in device tree.


Best regards,

Tao
Krzysztof Kozlowski Sept. 13, 2022, 9:14 a.m. UTC | #5
On 13/09/2022 09:00, Tao Zhang wrote:

>>> +  qcom,dsb-elem-size:
>>> +    description: |
>>> +      Specifies the DSB element size supported by each monitor
>>> +      connected to the aggregator on each port. Should be specified
>>> +      in pairs (port, dsb element size).
>>> +    $ref: /schemas/types.yaml#/definitions/uint32-array
>> So it is rather uint32-matrix (need to describe the items subschema).
>> What about maxItems?
>>
>> Best regards,
>> Krzysztof
> 
> Yes, indeed it should be uint32-matrix here. I will update in the next 
> release.
> 
> The "maxItems" cannot be known explicitly because it depends on how many 
> DSB subunit TPDMs are connected to the TPDA input ports.
> 
> Usually the number of the items is 1 to several, but there is no limit 
> to its maximum value.

OK, thanks.


Best regards,
Krzysztof
diff mbox series

Patch

diff --git a/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml b/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml
index eb9bfc5..1bb3fdf 100644
--- a/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml
+++ b/Documentation/devicetree/bindings/arm/qcom,coresight-tpda.yaml
@@ -40,6 +40,13 @@  properties:
     minItems: 1
     maxItems: 2
 
+  qcom,dsb-elem-size:
+    description: |
+      Specifies the DSB element size supported by each monitor
+      connected to the aggregator on each port. Should be specified
+      in pairs (port, dsb element size).
+    $ref: /schemas/types.yaml#/definitions/uint32-array
+
   clocks:
     maxItems: 1
 
@@ -82,6 +89,8 @@  examples:
        compatible = "qcom,coresight-tpda", "arm,primecell";
        reg = <0x6004000 0x1000>;
 
+       qcom,dsb-elem-size = <0 32>;
+
        clocks = <&aoss_qmp>;
        clock-names = "apb_pclk";