Re: [PATCH v4 1/2] ARM: keystone: pm: switch to use generic pm domains

From: Geert Uytterhoeven
Date: Fri Nov 21 2014 - 04:05:01 EST


On Thu, Nov 20, 2014 at 4:32 PM, Grygorii Strashko
<grygorii.strashko@xxxxxx> wrote:
>> That's indeed the tricky part.
>>
>> On shmobile, we just use the "NULL" clock, i.e. the first clock, for historical
>> reasons.
>>
>> Using clock-names (e.g. "fck" and "pm") will conflict with existing bindings
>> for devices that already mandate specific clock names.
>>
>> As the clock being a "PM" clock is a property of the clock provider
>> (at last on shmobile), I originally came up with not handling it in DT,
>> but advertising it in the clock provider driver:
>>
>>>> - first Geert Uytterhoeven proposed to use CLK_RUNTIME_PM there
>>>> https://lkml.org/lkml/2014/11/6/319
>
> As I mentioned previously I don't like it, because in many cases one driver is used for
> all/set_of clocks which support gating function. As result, some sort of tables will
> need to be created and maintained in code by these drivers per each SoC
> (or even per each SoC revision) for identification that clock is "PM clock".

That depends. On shmobile, there's a separate hardware module for those
clocks, hence all clocks provided by drivers/clk/shmobile/clk-mstp.c are "PM"
clocks.

Gr{oetje,eeting}s,

Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
-- Linus Torvalds
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