[PATCH RESEND 1/8] arm: dts: berlin2q: add watchdog nodes
Sebastian Hesselbarth
sebastian.hesselbarth at gmail.com
Sat Nov 28 03:36:16 PST 2015
On 23.11.2015 05:59, Jisheng Zhang wrote:
> On Fri, 20 Nov 2015 21:19:46 +0100
> Sebastian Hesselbarth wrote:
>> On 20.11.2015 04:34, Jisheng Zhang wrote:
>>> On Thu, 19 Nov 2015 21:47:05 +0100
>>> Sebastian Hesselbarth wrote:
>>>> On 16.11.2015 12:09, Jisheng Zhang wrote:
>>>>> The Marvell Berlin BG2Q has 3 watchdogs which are compatible with the
>>>>> snps,dw-wdt driver sit in the sysmgr domain. This patch adds the
>>>>> corresponding device tree nodes.
>>>>>
>>>>> Signed-off-by: Jisheng Zhang <jszhang at marvell.com>
>>>>> ---
[...]
>>>>> + wdt0: watchdog at 1000 {
>>>>> + compatible = "snps,dw-wdt";
>>>>> + reg = <0x1000 0x100>;
>>>>> + clocks = <&refclk>;
>>>>> + interrupts = <0>;
>>>>> + status = "disabled";
>>>>
>>>> as the watchdogs are internal and cannot be clock gated
>>>> at all, how about we remove the status = "disabled" and
>>>> make them always available?
>>>
>>> there are two issues here:
>>>
>>> 1. the dw-wdt can't support multiple variants now. I have rewrite the driver
>>> with watchdog core supplied framework, but the patch isn't sent out and
>>> may be need time to clean up and review.
>>
>> Ok.
>>
>>> 2. not all dw-wdt devices are available and functional. This depends on
>>> board design and configuration.
>>
>> I understand that "board design and configuration" may hinder the wdt
>> to issue a hard reset. But all others are able to issue a soft reset
>> or just an interrupt, right?
>>
>> So, I still don't see why we should disable wdt nodes by default
>> except for the driver issue above.
>>
>>> So IMHO status=disabled and patch5-8 is necessary, what do you think?
>>
>> No. I'd agree to enable wdt0 by default and leave wdt[1,2] disabled
>> because of the driver issue. Patches 5-8 only enable wdt0 anyway.
>
> That's fine.
Jisheng,
I amended your SoC dtsi watchdog patches accordingly. wdt0 is
now always enabled, while the others are disabled.
So, with the changes Patches 1-4 applied to berlin/dt and berlin64/dt
respectively. Patches 5-8 dropped.
>> As soon as the driver issue is resolved, we enable all wdt nodes
>> unconditionally.
>
> I will submit patch for the wdt driver and hope it will be merged
> in v4.5.
Ok. Feel free to add a patch that removes the status disabled properties
again if berlin[64]/dt has already hit mainline in the meantime.
If not, keep me posted on the DW wdt patch outcome.
Thanks,
Sebastian
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