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Message-ID: <645aca4d-b19c-390d-b899-fd40a924a096@ti.com>
Date:   Wed, 21 Dec 2022 13:12:14 +0530
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Subject: Re: [PATCH v2 1/2] Documentation: dt-bindings: k3-r5f-rproc: Add new
 compatible for AM62 SoC family
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To:     Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
        <andersson@kernel.org>, <mathieu.poirier@linaro.org>,
        <p.zabel@pengutronix.de>, <linux-remoteproc@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <devicetree@vger.kernel.org>,
        <s-anna@ti.com>
CC:     <robh+dt@kernel.org>, <krzysztof.kozlowski+dt@linaro.org>,
        <hnagalla@ti.com>, <praneeth@ti.com>, <nm@ti.com>,
        <vigneshr@ti.com>, <a-bhatia1@ti.com>, <j-luthra@ti.com>
References: <20221130134052.7513-1-devarsht@ti.com>
 <20221130134052.7513-2-devarsht@ti.com>
 <b4b608bf-e347-5500-eb94-bec3611f6a56@linaro.org>
From:   Devarsh Thakkar <devarsht@ti.com>
In-Reply-To: <b4b608bf-e347-5500-eb94-bec3611f6a56@linaro.org>
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Hi Krzysztof,

Thanks for the review. Please find my response inline.

On 30/11/22 20:33, Krzysztof Kozlowski wrote:
> On 30/11/2022 14:40, Devarsh Thakkar wrote:
>> AM62 family of devices don't have a R5F cluster, instead
>> they have single core DM R5F.
>> Add new compatible string ti,am62-r5fss to support this scenario.
>>
>> When this new compatible is used don't allow cluster-mode
>> property usage in device-tree as this implies that there
>> is no R5F cluster available and only single R5F core
>> is present.
>>
>> Signed-off-by: Devarsh Thakkar <devarsht@ti.com>
>> ---
>> V2: Avoid acronyms, use "Device Manager" instead of "DM"
> 
> Use subject prefixes matching the subsystem (git log --oneline -- ...).
Agreed, I will update the prefix as dt-bindings: remoteproc: k3-r5f: in V3.
> 
>> ---
>>  .../bindings/remoteproc/ti,k3-r5f-rproc.yaml  | 48 +++++++++++++------
>>  1 file changed, 34 insertions(+), 14 deletions(-)
>>
>> diff --git a/Documentation/devicetree/bindings/remoteproc/ti,k3-r5f-rproc.yaml b/Documentation/devicetree/bindings/remoteproc/ti,k3-r5f-rproc.yaml
>> index fb9605f0655b..91357635025a 100644
>> --- a/Documentation/devicetree/bindings/remoteproc/ti,k3-r5f-rproc.yaml
>> +++ b/Documentation/devicetree/bindings/remoteproc/ti,k3-r5f-rproc.yaml
>> @@ -21,6 +21,9 @@ description: |
>>    called "Single-CPU" mode, where only Core0 is used, but with ability to use
>>    Core1's TCMs as well.
>>  
>> +  AM62 SoC family support a single R5F core only which runs Device Manager
>> +  firmware and can also be used as a remote processor with IPC communication.
>> +
>>    Each Dual-Core R5F sub-system is represented as a single DTS node
>>    representing the cluster, with a pair of child DT nodes representing
>>    the individual R5F cores. Each node has a number of required or optional
>> @@ -28,6 +31,9 @@ description: |
>>    the device management of the remote processor and to communicate with the
>>    remote processor.
>>  
>> +  Since AM62 SoC family only support a single core, there is no cluster-mode
>> +  property setting required for it.
>> +
>>  properties:
>>    $nodename:
>>      pattern: "^r5fss(@.*)?"
>> @@ -38,6 +44,7 @@ properties:
>>        - ti,j721e-r5fss
>>        - ti,j7200-r5fss
>>        - ti,am64-r5fss
>> +      - ti,am62-r5fss
> 
> Some order? Alphabetical, so before am64? Same in other places.
Agreed, I will update in V3 accordingly.
> 
> 
>>        - ti,j721s2-r5fss
>>  
>>    power-domains:
>> @@ -80,7 +87,8 @@ patternProperties:
>>        node representing a TI instantiation of the Arm Cortex R5F core. There
>>        are some specific integration differences for the IP like the usage of
>>        a Region Address Translator (RAT) for translating the larger SoC bus
>> -      addresses into a 32-bit address space for the processor.
>> +      addresses into a 32-bit address space for the processor. For AM62x,
>> +      should only define one R5F child node as it has only one core available.
>>  
>>        Each R5F core has an associated 64 KB of Tightly-Coupled Memory (TCM)
>>        internal memories split between two banks - TCMA and TCMB (further
>> @@ -104,6 +112,7 @@ patternProperties:
>>            - ti,j721e-r5f
>>            - ti,j7200-r5f
>>            - ti,am64-r5f
>> +          - ti,am62-r5f
>>            - ti,j721s2-r5f
>>  
>>        reg:
>> @@ -207,20 +216,31 @@ patternProperties:
>>        - firmware-name
>>  
>>      unevaluatedProperties: false
> 
> Blank line.
Agreed, I will remove it in V3.
> 
>> +allOf:
>> +  - if:
>> +      properties:
>> +        compatible:
>> +          enum:
>> +            - ti,am64-r5fss
>> +    then:
>> +      properties:
>> +        ti,cluster-mode:
>> +          enum: [0, 2]
>> +
>> +    else:
>> +      properties:
>> +        ti,cluster-mode:
> 
> It's not really valid anymore for ti,am62-r5fss, so this cannot be
> simple "else".  Instead you need to list all compatibles.
I agree that the else block is not valid for am62x, but my understanding is that since all the blocks under allOf are checked for validity,
I thought to add a separate if block only for am62x to set cluster-mode to false [1], which I believe would negate the effect of above else condition for am62x,
so that we don't have to list all compatibles under separate if blocks.

Just to verify this, I deliberately set cluster-mode=1 in am62x devicetree and then ran a dtbs-check and got below log : 
"linux-next/arch/arm64/boot/dts/ti/k3-am625-sk.dtb: r5fss@78000000: ti,cluster-mode: False schema does not allow [[1]]"

and above warning log goes away when i remove the cluster-mode node in am62x devicetree.
But please do let me know if I am missing something here or there is a better/more proper way to do this.

Best Regards,
Devarsh

> 
>> +          enum: [0, 1]
>> +
[1]
>> +  - if:
>> +      properties:
>> +        compatible:
>> +          enum:
>> +            - ti,am62-r5fss
>> +    then:
>> +      properties:
>> +        ti,cluster-mode: false
>>  
>> -if:
>> -  properties:
>> -    compatible:
>> -      enum:
>> -        - ti,am64-r5fss
>> -then:
>> -  properties:
>> -    ti,cluster-mode:
>> -      enum: [0, 2]
>> -else:
>> -  properties:
>> -    ti,cluster-mode:
>> -      enum: [0, 1]
>>  
>>  required:
>>    - compatible
> 
> Best regards,
> Krzysztof
>