Re: [PATCH 1/5] dt-bindings: PCI: mediatek-gen3: Add MT8196 support

Chen-Yu Tsai
2025-01-07T09:02:25Z

On Tue, Jan 7, 2025 at 4:45 PM Jianjun Wang (王建军)
<Jianjun.Wang@mediatek.com> wrote:
>
> On Mon, 2025-01-06 at 13:27 +0100, Krzysztof Kozlowski wrote:
> > External email : Please do not click links or open attachments until
> > you have verified the sender or the content.
> >
> >
> > On 06/01/2025 10:26, Jianjun Wang (王建军) wrote:
> > > On Fri, 2025-01-03 at 10:10 +0100, Krzysztof Kozlowski wrote:
> > > > External email : Please do not click links or open attachments
> > > > until
> > > > you have verified the sender or the content.
> > > >
> > > >
> > > > On Fri, Jan 03, 2025 at 02:00:11PM +0800, Jianjun Wang wrote:
> > > > > + clock-names:
> > > > > + items:
> > > > > + - const: pl_250m
> > > > > + - const: tl_26m
> > > > > + - const: peri_26m
> > > > > + - const: peri_mem
> > > > > + - const: ahb_apb
> > > > > + - const: low_power
> > > > > +
> > > > > + resets:
> > > > > + minItems: 1
> > > > > + maxItems: 2
> > > > > +
> > > > > + reset-names:
> > > > > + minItems: 1
> > > > > + maxItems: 2
> > > >
> > > > Why resets are flexible?
> > >
> > > There are two resets, one for MAC and another for PHY, some
> > > platforms
> > > may only use one of them.
> >
> > Even more questions. What does it mean use? Is it there or is it not?
>
> It will be used by calling the reset controller's APIs in the PCIe
> controller driver. Ideally, it should be de-asserted before PCIe
> initialization and should be asserted if PCIe powers down or the driver
> is removed.
>
> > Platform like SoC? But this is one specific SoC, it cannot be used on
> > different SoC.
>
> Yes, it should be SoC, each SoC have its own resets, and the number of
> resets for each SoC is defined by the hardware design, most SoCs should
> have one reset for MAC and one reset for PHY.
>
> >
> > >
> > > Would you prefer to set the number of resets to a fixed value for
> > > specific platforms?
> >
> > Everything should be constrained to match hardware.
>
> For MT8196, there are 2 resets. Should I use a fixed item in this case?

Yes. As you said, MT8196 has two resets, therefore the binding should
say it requires two resets.

So in the second part where it matches against mt8196, you should
have minItems = maxItems = 2.

ChenYu

> Thanks.
>
> >
> >
> > Best regards,
> > Krzysztof
> >