Hi Sato-san,
On Wed, Jan 17, 2024 at 10:46 AM Yoshinori Sato
<ysato@xxxxxxxxxxxxxxxxxxxx> wrote:
> On Tue, 09 Jan 2024 21:30:34 +0900,
> Linus Walleij wrote:
> > On Tue, Jan 9, 2024 at 9:24 AM Yoshinori Sato
> > <ysato@xxxxxxxxxxxxxxxxxxxx> wrote:
> >
> > > + renesas,icr-irlm:
> > > + $ref: /schemas/types.yaml#/definitions/flag
> > > + description: If true four independent interrupt requests mode (ICR.IRLM is 1).
> > > +
> > > + renesas,ipr-map:
> > > + $ref: /schemas/types.yaml#/definitions/uint32-array
> > > + description: |
> > > + IRQ to IPR mapping definition.
> > > + 1st - INTEVT code
> > > + 2nd - Register
> > > + 3rd - bit index
> >
> > (...)
> >
> > > + renesas,ipr-map = <0x240 IPRD IPR_B12>, /* IRL0 */
> > > + <0x2a0 IPRD IPR_B8>, /* IRL1 */
> > > + <0x300 IPRD IPR_B4>, /* IRL2 */
> > > + <0x360 IPRD IPR_B0>, /* IRL3 */
> > (...)
> >
> > Is it really necessary to have all this in the device tree?
> >
> > You know from the compatible that this is "renesas,sh7751-intc"
> > and I bet this table will be the same for any sh7751 right?
> >
> > Then just put it in a table in the driver instead and skip this from
> > the device tree and bindings. If more interrupt controllers need
> > to be supported by the driver, you can simply look up the table from
> > the compatible string.
>
> The SH interrupt controller has the same structure, only this part is different for each SoC.
> Currently, we are targeting only the 7751, but in the future we plan to handle all SoCs.
> Is it better to differentiate SoC only by compatible?
Yes, it is better to differentiate SoC only by compatible value.
When you describe all differences explicitly using properties, you
might discover later that you missed something important, causing
backwards compatibility issues with old DTBs.
DT is a stable ABI, while you can always update a driver when needed.
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
