Re: [EXT] Re: [PATCH 1/2 v5] dt-bindings: watchdog: marvell GTI system watchdog driver

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 05/05/2023 13:15, Bharat Bhushan wrote:
> 
> 
>> -----Original Message-----
>> From: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
>> Sent: Friday, May 5, 2023 4:27 PM
>> To: Bharat Bhushan <bbhushan2@xxxxxxxxxxx>; wim@xxxxxxxxxxxxxxxxxx;
>> linux@xxxxxxxxxxxx; robh+dt@xxxxxxxxxx; krzysztof.kozlowski+dt@xxxxxxxxxx;
>> linux-watchdog@xxxxxxxxxxxxxxx; devicetree@xxxxxxxxxxxxxxx
>> Subject: Re: [EXT] Re: [PATCH 1/2 v5] dt-bindings: watchdog: marvell GTI system
>> watchdog driver
>>
>> On 05/05/2023 12:41, Bharat Bhushan wrote:
>>>>>>
>>>>>> You need anyway SoC specific compatibles. Once you add proper
>>>>>> compatibles, you will see that property is not needed.
>>>>>
>>>>> Also on a given soc, firmware can configure one of 64 timer to be
>>>>> used as
>>>> system watchdog time then compatible will not work.
>>>>
>>>> Can't you query the firmware for that? Or can't you just choose first
>>>> unused timer? DT is for non-discoverable properties.
>>>
>>> Query to firmware required arm SMC call, to me that does not look correct
>> approach. Thought of using first one but that is already used and moving that is as
>> same as this.
>>>
>>> Hardcoding to 63 will make it work on some SoCs but not all.
>>
>> But you know which one is started or is not. GTI_CWD_WDOG tells you this.
> 
> On a given SoC, Firmware can reserve and/or use one or more timer for some other use case (customer use) and configure one of the timer as watchdog timer. Linux have to use the configured timer only and cannot decide by its own.

Then the SoCs which have such firmware could use proposed property.
Provide some rationale property description in your next version (adding
necessary compatibles).

Best regards,
Krzysztof




[Index of Archives]     [Device Tree Compilter]     [Device Tree Spec]     [Linux Driver Backports]     [Video for Linux]     [Linux USB Devel]     [Linux PCI Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Yosemite Backpacking]


  Powered by Linux