Re: [RFC PATCH v3 25/35] Documentation/devicetree/bindings/sh/cpus.yaml: Add SH CPU.

Hi Jeff,

On Wed, Oct 25, 2023 at 2:10 PM D. Jeff Dionne <[email protected]> wrote:
> On Oct 25, 2023, at 21:04, Geert Uytterhoeven <[email protected]> wrote:
> > On Wed, Oct 25, 2023 at 1:33 PM D. Jeff Dionne <[email protected]> wrote:
> >>> On Oct 25, 2023, at 20:14, Yoshinori Sato <[email protected]> wrote:
> >>> On Wed, 18 Oct 2023 23:27:43 +0900,
> >>> Geert Uytterhoeven wrote:
> >>>> On Sat, Oct 14, 2023 at 4:54 PM Yoshinori Sato
> >>>> <[email protected]> wrote:
> >>>>> Renesas SuperH binding definition.
> >>>>>
> >>>>> Signed-off-by: Yoshinori Sato <[email protected]>
> >
> >>>>> --- /dev/null
> >>>>> +++ b/Documentation/devicetree/bindings/sh/cpus.yaml

> >>>>> +properties:
> >>>>> +  compatible:
> >>>>> +    items:
> >>>>> +      - enum:
> >>>>
> >>>> Missing
> >>>>
> >>>>   - jcore,j2
> >
> >> We must not imply that Renesas is responsible for J2, or that it is a sanctioned SH core.
> >
> > Compatible values do not declare any such endorsement.
> >
> >> J-Core has the responsibility for maintenance of those SH ISA compatible cores.
> >
> > The question is: does J2 implement the same instruction set as SH2,
> > i.e. can it run unmodified SH2 code?
>
> It can run all SH2 code, but an SH2 cannot run all J2 code.

This is exactly what

    compatible = "jcore,j2", "renesas,sh2";

represents.
Cfr. Section 2.3.1 ("compatible") of the Devicetree Specification
https://www.devicetree.org/specifications

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- [email protected]

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