Re: [PATCH v2 5/8] MIPS: jz4740: dts: Add bindings for the jz4740-wdt driver

From: PrasannaKumar Muralidharan
Date: Wed Jan 03 2018 - 09:28:11 EST


Hi Guenter,

On 3 January 2018 at 10:16, Guenter Roeck <linux@xxxxxxxxxxxx> wrote:
> On 01/02/2018 08:48 AM, Paul Cercueil wrote:
>>
>> Hi PrasannaKumar,
>>
>> Le mar. 2 janv. 2018 Ã 17:37, PrasannaKumar Muralidharan
>> <prasannatsmkumar@xxxxxxxxx> a Ãcrit :
>>>
>>> Hi Paul,
>>>
>>> On 30 December 2017 at 19:21, Paul Cercueil <paul@xxxxxxxxxxxxxxx> wrote:
>>>>
>>>> Also remove the watchdog platform_device from platform.c, since it
>>>> wasn't used anywhere anyway.
>>>>
>>>> Signed-off-by: Paul Cercueil <paul@xxxxxxxxxxxxxxx>
>>>> ---
>>>> arch/mips/boot/dts/ingenic/jz4740.dtsi | 8 ++++++++
>>>> arch/mips/jz4740/platform.c | 16 ----------------
>>>> 2 files changed, 8 insertions(+), 16 deletions(-)
>>>>
>>>> v2: No change
>>>>
>>>> diff --git a/arch/mips/boot/dts/ingenic/jz4740.dtsi
>>>> b/arch/mips/boot/dts/ingenic/jz4740.dtsi
>>>> index cd5185bb90ae..26c6b561d6f7 100644
>>>> --- a/arch/mips/boot/dts/ingenic/jz4740.dtsi
>>>> +++ b/arch/mips/boot/dts/ingenic/jz4740.dtsi
>>>> @@ -45,6 +45,14 @@
>>>> #clock-cells = <1>;
>>>> };
>>>>
>>>> + watchdog: watchdog@10002000 {
>>>> + compatible = "ingenic,jz4740-watchdog";
>>>> + reg = <0x10002000 0x10>;
>>>> +
>>>> + clocks = <&cgu JZ4740_CLK_RTC>;
>>>> + clock-names = "rtc";
>>>> + };
>>>> +
>>>
>>>
>>> The watchdog driver calls jz4740_timer_enable_watchdog and
>>> jz4740_timer_disable_watchdog which defined in
>>> arch/mips/jz4740/timer.c. It accesses registers iomapped by timer
>>> code. Declaring register size as 0x10 does not show the real picture.
>>> Better use register size as 0x100 and let timer, wdt, pwm drivers to
>>> share them.
>>
>>
>> As you said, it accesses registers iomapped by timer code. So the watchdog
>> driver doesn't need to iomap them.
>>
>>> Code from one of your branches
>>>
>>> (https://github.com/OpenDingux/linux/blob/for-upstream-clocksource/arch/mips/boot/dts/ingenic/jz4740.dtsi)
>>> does it. Can you prepare a patch series and send it?
>>> I have a patch set that moves timer code out of arch/mips/jz4740/ and
>>> does a similar thing for watchdog and pwm. As your new timer driver is
>>> better than the existing one I have not sent my patches yet. I would
>>> like to see it getting mainlined as it paves way for removing most of
>>> code in arch/mips/jz4740.
>>
>>
>> The whole 'for-upstream-clocksource' branch is supposed to go upstream,
>> but I can't do it in one big patchset without having lots of breakages
>> with
>> my other patchsets (jz4770 SoC support, and jz4740 watchdog updates)
>> currently under review. That also makes it simpler to upstream than having
>> one single patchset that touches 6 different frameworks (MIPS, irq,
>> clocks,
>> clocksource, watchdog, PWM).
>>
>> So I will submit it in two steps, first the irq/clocks/clocksource drivers
>> (this patchset) hopefully for 4.16, and then the platform/watchdog/PWM
>> fixes
>> for 4.17.
>>
>
> I kind of lost it in this exchange, sorry. At this point I don't know if
> something
> is wrong with the watchdog patches, and I have no clue what the upstream
> path

There is nothing wrong in this watchdog patches.

> is supposed to be. My working assumption is that 1) something may be wrong
> with
> the current version of the patches, and, 2), even if not, none of the
> patches
> is expected to find its way upstream through the watchdog subsystem. Plus,
> 3),
> even if some of the patches are supposed to go upstream through the watchdog
> subsystem, that won't happen in 4.16, and the patches will be resubmitted
> later
> when they are ready [and will hopefully marked clearly for submission
> through
> the watchdog subsystem].
>
> With that in mind, I'll mark the series for my reference as "not
> applicable".
> If this is wrong please let me know.

Paul has patches related to timer code. While sending that he would
send changes to watchdog dts entry also. I was suggesting him to send
timer patches together with watchdog patches as a single patch series
but he prefers to send them as separate patch series.

I would like to reiterate that there is nothing wrong with this
watchdog patches. I should have set the correct context in my previous
email itself. I sincerely apologize for creating this confusion.

Regards,
PrasannaKumar