Re: [PATCH v4 5/7] Watchdog: introduce ARM SBSA watchdog driver

From: Fu Wei
Date: Wed Jun 10 2015 - 23:01:09 EST


On 11 June 2015 at 08:22, Timur Tabi <timur@xxxxxxxxxxxxxx> wrote:
> Fu Wei wrote:
>>
>> If we make the first stage timeout is timeout/2, this violates the
>> definition of timeout.
>
>
> The documentation says that the hardware needs to reset after the timeout
> expires.

yes , you are absolutely on this. Great thanks for point out this.
my patch is doing this way: trigger WS1 at the timeout expires
Before that, using pretimeout for WS0 as an warning.


> If you program the hardware to timeout/2, the driver can ignore
> WS0 and allow WS1 to reset the hardware. That conforms to the
> documentation.

yes, technically we can do nothing in WS0, and just wait for WS1.
So SBSA watchdog become a one stage timeout watchdog, right?
So if user want the WS0 warning, How to make driver know that, and do
something in WS0 routine?
I think by this way, two stage timeouts, WS0 "alert" will be meaningless.

Could you suggest a good way to use WS0, so we can follow SBSA spec?

>
> --
> Sent by an employee of the Qualcomm Innovation Center, Inc.
> The Qualcomm Innovation Center, Inc. is a member of the
> Code Aurora Forum, hosted by The Linux Foundation.



--
Best regards,

Fu Wei
Software Engineer
Red Hat Software (Beijing) Co.,Ltd.Shanghai Branch
Ph: +86 21 61221326(direct)
Ph: +86 186 2020 4684 (mobile)
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