Re: [PATCH RFC 3/6] dt-bindings: watchdog: Add Qualcomm restart reason binding

[Kathiravan Thirumoorthy <kathiravan.thirumoorthy@oss.qualcomm.com>]

On 4/9/2025 12:30 PM, Krzysztof Kozlowski wrote:
> On 08/04/2025 10:49, Kathiravan Thirumoorthy wrote:
>> Add a devicetree binding for the Qualcomm IPQ SOCs restart reason
>> information region found in the IMEM, allowing the system to identify
>> the cause of a restart.
>>
>> Signed-off-by: Kathiravan Thirumoorthy <kathiravan.thirumoorthy@oss.qualcomm.com>
>> ---
>>   .../bindings/watchdog/qcom,restart-reason.yaml     | 46 ++++++++++++++++++++++
>>   1 file changed, 46 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/watchdog/qcom,restart-reason.yaml b/Documentation/devicetree/bindings/watchdog/qcom,restart-reason.yaml
>> new file mode 100644
>> index 0000000000000000000000000000000000000000..babbaa70b114f9691018ed6cb10bfa78e18fad64
>> --- /dev/null
>> +++ b/Documentation/devicetree/bindings/watchdog/qcom,restart-reason.yaml
>> @@ -0,0 +1,46 @@
>> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
>> +%YAML 1.2
>> +---
>> +$id: http://devicetree.org/schemas/watchdog/qcom,restart-reason.yaml#
>> +$schema: http://devicetree.org/meta-schemas/core.yaml#
>> +
>> +title: Qualcomm IPQ SoC restart reason location
>> +
>> +maintainers:
>> +  - Kathiravan Thirumoorthy <kathiravan.thirumoorthy@oss.qualcomm.com>
>> +
>> +description:
>> +  The Qualcomm IPQ SoC restart reason memory region, in IMEM, is used to
>> +  identify the cause of the system restart. This will be helpful to identify
>> +  the cause when the RAM dump collection is disabled.
>> +
>> +properties:
>> +  compatible:
>> +    const: qcom,restart-reason-info
> No generic compatibles.
>
> OTOH, I don't see much of a value of this being a separate node.

I leveraged this based on the qcom,pil-info.yaml [1]. I guess, I see the 
point. I will drop all these. Just define IMEM node and in the watchdog 
driver, I will get the regmap of the syscon / IMEM node and do 
regmap_read at the desired offset. Please let me know if this approach 
is fine.

[1] 
https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/Documentation/devicetree/bindings/remoteproc/qcom,pil-info.yaml