Re: [net-next PATCH v3 4/5] net: phy: Introduce fwnode_get_phy_id()

From: Russell King - ARM Linux admin
Date: Mon May 11 2020 - 09:35:37 EST


On Mon, May 11, 2020 at 03:04:57PM +0200, Andrew Lunn wrote:
> > NXP's LX2160ARDB platform currently has the following MDIO-PHY connection.
> >
> > MDIO-1 ==> one 40G PHY, two 1G PHYs(C45), two 10G PHYs(C22)
> > MDIO-2 ==> one 25G PHY
>
> It has been suggested that ACPI only support a one to one
> mapping. Each MAC has one MDIO bus, with one PHY on it. KISS.
>
> This clearly does not work for your hardware. So not only do we need
> to solve how PHY properties are described, we also need an equivalent
> of phy-handle, so a MAC can indicate which PHY it is connected to.

I'd suggest that doesn't work for a lot of hardware. It won't work for
the Macchiatobin for example, where there are two Clause 45 NBASE-T
PHYs on one MDIO bus.

The same is likely true on the LX2160A - there can be multiple ethernet
interfaces, but IIRC only two external MDIO buses that one can hang
PHYs off of.

--
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