Re: [PATCH] dt-bindings: mmc: renesas,sdhi: Document RZ/T2H and RZ/N2H support

From: Lad, Prabhakar
Date: Fri Jun 13 2025 - 14:59:21 EST


Hi Geert,

On Fri, Jun 13, 2025 at 4:37 PM Lad, Prabhakar
<prabhakar.csengg@xxxxxxxxx> wrote:
>
> Hi Geert,
>
> Thank you for the review.
>
> On Thu, Jun 12, 2025 at 4:47 PM Geert Uytterhoeven <geert@xxxxxxxxxxxxxx> wrote:
> >
> > Hi Prabhakar,
> >
> > On Tue, 10 Jun 2025 at 01:23, Prabhakar <prabhakar.csengg@xxxxxxxxx> wrote:
> > > From: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
> > >
> > > Add SDHI bindings for the Renesas RZ/T2H (a.k.a R9A09G077) and RZ/N2H
> > > (a.k.a R9A09G087) SoCs. Use `renesas,sdhi-r9a09g057` as a fallback since
> > > the SD/MMC block on these SoCs is identical to the one on RZ/V2H(P),
> > > allowing reuse of the existing driver without modifications.
> > >
> > > Update the binding schema to reflect differences: unlike RZ/V2H(P),
> > > RZ/T2H and RZ/N2H do not require the `resets` property and use only a
> > > single clock instead of four.
> > >
> > > Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
> >
> > Thanks for your patch!
> >
> > > --- a/Documentation/devicetree/bindings/mmc/renesas,sdhi.yaml
> > > +++ b/Documentation/devicetree/bindings/mmc/renesas,sdhi.yaml
> > > @@ -129,59 +131,75 @@ allOf:
> > > compatible:
> > > contains:
> > > enum:
> > > - - renesas,sdhi-r9a09g057
> > > - - renesas,rzg2l-sdhi
> > > + - renesas,sdhi-r9a09g077
> > > + - renesas,sdhi-r9a09g087
> > > then:
> > > properties:
> > > + resets: false
> > > clocks:
> > > - items:
> > > - - description: IMCLK, SDHI channel main clock1.
> > > - - description: CLK_HS, SDHI channel High speed clock which operates
> > > - 4 times that of SDHI channel main clock1.
> > > - - description: IMCLK2, SDHI channel main clock2. When this clock is
> > > - turned off, external SD card detection cannot be
> > > - detected.
> > > - - description: ACLK, SDHI channel bus clock.
> > > + description: ACLK, SDHI channel bus clock.
> >
> > According to the documentation, this is the SDHI high speed clock...
> >
Actually re-reading the doc there are two clocks (I had missed the
second clock earlier),
1] ACLK, IMCLK from the PCLKAM which is 200MHz
2] SDHI_clkhs from PLL2 which is 800MHz
Note, on RZ/V2H too the ACLK/IMCLK is 200MHz and clk_hs is 800MHz

So, I'll represent them as below:
clocks:
items:
- description: ACLK, IMCLK, SDHI channel bus and main clocks.
- description: CLK_HS, SDHI channel High speed clock.
clock-names:
items:
- const: aclk
- const: clkh

And for the ACLK, IMCLK which comes from peripheral module clock
(PCLKAM) this will be a module clock and CLK_HS will have to be
modelled as a CORE clock.

Cheers,
Prabhakar