Re: [PATCH 17/25] serial: sh-sci: Correct SCIF type on R-Car for BRG

From: Laurent Pinchart
Date: Fri Nov 20 2015 - 10:33:00 EST


Hi Geert,

On Friday 20 November 2015 16:30:22 Geert Uytterhoeven wrote:
> On Fri, Nov 20, 2015 at 3:52 PM, Laurent Pinchart wrote:
> > On Friday 20 November 2015 08:46:56 Geert Uytterhoeven wrote:
> >> On Thu, Nov 19, 2015 at 9:55 PM, Laurent Pinchart wrote:
> >>> On Thursday 19 November 2015 19:38:56 Geert Uytterhoeven wrote:
> >>>> The "renesas,scif" compatible value is currently used for the SCIF
> >>>> variant in all Renesas SoCs of the R-Car family. However, the variant
> >>>> used in the R-Car family is not the common "SH-4(A)" variant, but a
> >>>> derivative with added "Baud Rate Generator for External Clock" (BRG),
> >>>> which is also present in sh7734.
> >>>
> >>> Time to introduce a "renesas,scif-rcar" compatible string ? ;-)
> >>>
> >>> As the only DT-enabled platform to have a different SCIF type is
> >>> r7s72100 we could also consider just switching the regtype to
> >>> SCIx_SH4_SCIF_BRG_REGTYPE for the generic "renesas,scif" entry as it's
> >>> listed after the "renesas,scif- r7s72100" entry. That might cause an
> >>> issue if we want to enable DT on arch/sh though, but even if that
> >>> happens due to the J-Core processors I'd be surprised to see the old
> >>> Renesas SH platforms being moved to DT.
> >>
> >> I thought about that, but you never know in which out-of-tree BSP it
> >> ended up being used, too. So better safe than sorry.
> >
> > Out-of-tree should be banned :-)
> >
> > More seriously, I suppose you wouldn't be thrilled by the idea of a
> > "renesas,scif-rcar-gen2" ?
>
> Nope. Note that it's also used in R-Car Gen 1 and Gen 3, and sh7734.

Yes, but it would at least cover the whole Gen2 family that behaves the same
way. And wouldn't preclude adding "renesas,scif-rcar-gen1". That's two compat
strings only.

--
Regards,

Laurent Pinchart

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