Re: [PATCH net-next v3 2/3] net: phy: add Broadcom BCM54140 support
From: David Miller
Date: Wed Apr 22 2020 - 15:15:31 EST
From: Michael Walle <michael@xxxxxxxx>
Date: Mon, 20 Apr 2020 20:21:12 +0200
> The Broadcom BCM54140 is a Quad SGMII/QSGMII Copper/Fiber Gigabit
> Ethernet transceiver.
>
> This also adds support for tunables to set and get downshift and
> energy detect auto power-down.
>
> The PHY has four ports and each port has its own PHY address.
> There are per-port registers as well as global registers.
> Unfortunately, the global registers can only be accessed by reading
> and writing from/to the PHY address of the first port. Further,
> there is no way to find out what port you actually are by just
> reading the per-port registers. We therefore, have to scan the
> bus on the PHY probe to determine the port and thus what address
> we need to access the global registers.
>
> Signed-off-by: Michael Walle <michael@xxxxxxxx>
Applied.