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

Jianjun Wang (王建军)
2025-01-08T06:54:06Z

On Tue, 2025-01-07 at 17:02 +0800, Chen-Yu Tsai wrote:
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>
> 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.
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> > > > >
> > > > > 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.

Got it, I'll fix it in the next version.

Thanks.

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