Re: [PATCH v4 3/5] dt-bindings: watchdog: qcom-wdt: Document qcom,imem property

[Krzysztof Kozlowski <krzk@kernel.org>]

On 20/05/2025 18:00, Konrad Dybcio wrote:
> On 5/20/25 9:25 AM, Krzysztof Kozlowski wrote:
>> On Mon, May 19, 2025 at 02:04:03PM GMT, Kathiravan Thirumoorthy wrote:
>>> Document the "qcom,imem" property for the watchdog device on Qualcomm
>>> IPQ platforms. Use this property to extract the restart reason from
>>> IMEM, which is updated by XBL. Populate the watchdog's bootstatus sysFS
>>> entry with this information, when the system reboots due to a watchdog
>>> timeout.
>>>
>>> Describe this property for the IPQ5424 watchdog device and extend support
>>> to other targets subsequently.
>>>
>>> Signed-off-by: Kathiravan Thirumoorthy <kathiravan.thirumoorthy@oss.qualcomm.com>
>>> ---
>>> Changes in v4:
>>> 	- New patch
>>> ---
>>>  .../devicetree/bindings/watchdog/qcom-wdt.yaml       | 20 ++++++++++++++++++++
>>>  1 file changed, 20 insertions(+)
>>>
>>> diff --git a/Documentation/devicetree/bindings/watchdog/qcom-wdt.yaml b/Documentation/devicetree/bindings/watchdog/qcom-wdt.yaml
>>> index 49e2b807db0bc9d3edfc93ec41ad0df0b74ed032..bbe9b68ff4c8b813744ffd86bb52303943366fa2 100644
>>> --- a/Documentation/devicetree/bindings/watchdog/qcom-wdt.yaml
>>> +++ b/Documentation/devicetree/bindings/watchdog/qcom-wdt.yaml
>>> @@ -81,6 +81,16 @@ properties:
>>>      minItems: 1
>>>      maxItems: 5
>>>  
>>> +  qcom,imem:
>>
>> Shoouldn't this be existing 'sram' property? If IMEM is something
>> similar to OCMEM, then we already use sram for that.
> 
> We specifically want a handle to a predefined byte in IMEM, something akin
> to qcom,4ln-config-sel in
> 
> Documentation/devicetree/bindings/phy/qcom,sc8280xp-qmp-pcie-phy.yaml

Nothing stops that with sram. Above example is poor, because it mentions
syscon. There is no hardware as syscon. Does not exist. What is IMEM
here, what is this relationship?

Best regards,
Krzysztof