Re: [PATCH 2/3] dt-bindings: rtc: Add Mstar SSD20xD RTC devicetree bindings documentation

From: Krzysztof Kozlowski
Date: Wed May 31 2023 - 02:49:20 EST

On 31/05/2023 01:12, Daniel Palmer wrote:
> Hi Krzysztof,
> On Tue, 30 May 2023 at 17:01, Krzysztof Kozlowski <krzk@xxxxxxxxxx> wrote:
>>> This is
>>> exactly the case for rtc-msc313e and it was not an issue.
>> So that was my question - can it be anything else? There is literally no
>> description of the hardware... Neither in commit msg nor in description:
>> field in bindings.
> This RTC block is a block inside of the SSD201/SSD202D (they are the

But what is SSD201?

> same die with different memory attached) and is only found there.
> The documentation we have for this is literally one page in a PDF that
> says "RTC registers".
> It could be an IP block licensed from somewhere and technically have a
> better name but right now all we know is this RTC block is the one in
> that chip and that chip is the first known instance of it.
> Say we manage to get the ethernet mainlined at some point: That's a
> lot easier as we know already it's a hacked up version of the cadence
> macb so the compatible can be "macb something".
>>>> What about interrupt line?
>>> There is currently no interrupt right now, we have not yet the irqchip
>>> code for handling the alarm irq of this rtc block.
>> So you are going to change the hardware and add the interrupt line? We
>> do not talk about drivers, but hardware. Whether your driver handles it
>> or not, matters less.
>> Describe the hardware, not the current implementation of one driver.
> We don't really know how the interrupt is wired up in the hardware properly yet.


Best regards,