Re: [PATCH 2/2] [RFC] base: soc: Allow early registration of a single SoC device

From: Arnd Bergmann
Date: Mon Mar 13 2017 - 09:28:49 EST


On Mon, Mar 13, 2017 at 2:13 PM, Geert Uytterhoeven
<geert@xxxxxxxxxxxxxx> wrote:
> Hi Arnd,
>
> On Mon, Mar 13, 2017 at 2:06 PM, Arnd Bergmann <arnd@xxxxxxxx> wrote:
>> On Mon, Mar 13, 2017 at 1:46 PM, Geert Uytterhoeven
>> <geert@xxxxxxxxxxxxxx> wrote:
>>> On Mon, Mar 13, 2017 at 1:41 PM, Arnd Bergmann <arnd@xxxxxxxx> wrote:
>>>> On Thu, Mar 9, 2017 at 7:18 PM, Geert Uytterhoeven
>>>> I'd prefer to not have to do the early registration at all and have fewer
>>>> special cases. Can you list a specific example that requires this?
>>>
>>> The specific example is the Renesas R-Car SYSC driver, which manages PM
>>> Domains and thus needs to be initialized from an early_initcall.
>>
>> Ok, and what prevents us from using information in DT to detect which
>> variant we have? Is this a case of absolutely having to know the exact
>> hardware revision at the time of initialization, or is it just to simplify the
>> implementation of the SYSC driver?
>
> The former.
> Preproduction versions of R-Car H3 have an additional power area, which no
> longer exists on H3 ES2.0.

Ok. I'm still not happy about adding the workaround, but this seems like
a reasonable requirement, assuming that the preproduction versions of R-Car H3
are important enough to you that supporting them in mainline helps you
get your work done better.

Please add the explanation to the changelog, along with my

Acked-by: Arnd Bergmann <arnd@xxxxxxxx>