Re: [PATCH 7/9] watchdog: of_xilinx_wdt: Add Versal Window watchdog support

[Guenter Roeck]

On 3/23/21 11:04 PM, Srinivas Neeli wrote:
> Hi Guenter,
> 
> Thanks for review
> 
>> -----Original Message-----
>> From: Guenter Roeck <groeck7@xxxxxxxxx> On Behalf Of Guenter Roeck
>> Sent: Tuesday, March 16, 2021 8:01 AM
>> To: Srinivas Neeli <sneeli@xxxxxxxxxx>; Michal Simek <michals@xxxxxxxxxx>;
>> Shubhrajyoti Datta <shubhraj@xxxxxxxxxx>; Srinivas Goud
>> <sgoud@xxxxxxxxxx>
>> Cc: wim@xxxxxxxxxxxxxxxxxx; linux-watchdog@xxxxxxxxxxxxxxx; linux-arm-
>> kernel@xxxxxxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; git
>> <git@xxxxxxxxxx>
>> Subject: Re: [PATCH 7/9] watchdog: of_xilinx_wdt: Add Versal Window
>> watchdog support
>>
>> On 3/15/21 3:46 AM, Srinivas Neeli wrote:
>>> Versal watchdog driver uses Window watchdog mode. Window watchdog
>>> timer(WWDT) contains closed(first) and open(second) window with
>>> 32 bit width. WWDT will generate an interrupt after the first window
>>> timeout and reset signal after the second window timeout. Timeout and
>>> Pre-timeout configuration, Stop and Refresh trigger only in open
>>> window.
>>>
>>> Signed-off-by: Srinivas Neeli <srinivas.neeli@xxxxxxxxxx>
>>
>> I think this should be a separate watchdog driver. There is pretty much no
>> overlap with the existing driver.
> 
> Xilinx AXI Timebase Watchdog Timer supports two independent modes
> 1)Timebase Watchdog Mode
> 2)Window Watchdog Timer Mode.
> Current of_xilinx_wdt.c driver already have support for Timebase Watchdog Mode, but Window watchdog timer Mode feature is missing.
> Versal platform contains customized AXI Timebase Watchdog Timer, which supports Window Watchdog Timer Mode.
> For that reason we are creating common driver for both the modes.
> 

That is not an argument. The two watchdogs are still completely different,
and there is no value having a single driver.

Guenter