[PATCH v4] ARM: dts: add DT for lan966 SoC and 2-port board pcb8291

Kavyasree.Kotagiri at microchip.com Kavyasree.Kotagiri at microchip.com
Fri Feb 18 04:28:06 PST 2022


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> Am 2022-02-10 12:52, schrieb Kavyasree.Kotagiri at microchip.com:
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> >> Am 2022-02-10 10:40, schrieb Kavyasree.Kotagiri at microchip.com:
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> >> >> > +     clocks {
> >> >> [..]
> >> >> > +
> >> >> > +             nic_clk: nic_clk {
> >> >>
> >> >> What does nic_clk stand for? If I had to guess, it
> >> >> has something to do with network. But..
> >> >>
> >> > NIC clock is the clock used by AXI, AHB fabric and APB bridges which
> >> > connects all the peripherals.
> >> > It is named so because the AXI fabric is based on NIC400 IP from ARM
> >>
> >> Ok, thanks for clarification.
> >>
> >>
> >> >> > +             watchdog: watchdog at e0090000 {
> >> >> > +                     compatible = "snps,dw-wdt";
> >> >> > +                     reg = <0xe0090000 0x1000>;
> >> >> > +                     interrupts = <GIC_SPI 38 IRQ_TYPE_LEVEL_HIGH>;
> >> >> > +                     clocks = <&nic_clk>;
> >> >>
> >> >> Btw. can we disable all nodes by default and enable them
> >> >> in the board dts files?
> >> > I would like to have only board specific nodes enabled in dts files
> >> > and rest of them in dtsi file
> >>
> >> And how do you know which ones are board specific? E.g. I would like
> >> to add our board which is also based on the lan9668. Maybe I don't
> >> want a watchdog (or whatever node). Of course I could use
> >>
> >> &watchdog {
> >>    status = "disabled";
> >> };
> >>
> >> But IMHO opt-in is better. At least thats what we are doing for
> >> the layerscape over on arm64.
> >>
> > Basically, I am disabling only the nodes which have pinctrl settings
> > in dtsi file
> > and enable in dts to make sure there are no conflicts on pins on the
> > board.
> 
> Thats not what I'm asking. I would like to see *optional* nodes
> disabled by default. Whether the watchdog is optional might be
> debatable, but what about the usb controller and the qspi
> controller? They don't have shared pins AFAIK, so according
> to your rule, they will be enabled by default and each board
> which doesn't have anything connected on these pins would have
> to disabled it.
> 
> Please keep in mind that this .dtsi will also be used by boards
> not manufactured by microchip.
> 
I agree with you - "disabling optional nodes in dtsi"
I have gone through all the nodes.
Confirmed and moved enabling optional node watchdog
to dts file.

> -michael



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