Re: [PATCH net-next v4 1/4] net: mdio: Introduce a regmap-based mdio driver
From: Simon Horman
Date: Mon Jun 05 2023 - 03:37:38 EST
On Thu, Jun 01, 2023 at 04:14:51PM +0200, Maxime Chevallier wrote:
> There exists several examples today of devices that embed an ethernet
> PHY or PCS directly inside an SoC. In this situation, either the device
> is controlled through a vendor-specific register set, or sometimes
> exposes the standard 802.3 registers that are typically accessed over
> MDIO.
>
> As phylib and phylink are designed to use mdiodevices, this driver
> allows creating a virtual MDIO bus, that translates mdiodev register
> accesses to regmap accesses.
>
> The reason we use regmap is because there are at least 3 such devices
> known today, 2 of them are Altera TSE PCS's, memory-mapped, exposed
> with a 4-byte stride in stmmac's dwmac-socfpga variant, and a 2-byte
> stride in altera-tse. The other one (nxp,sja1110-base-tx-mdio) is
> exposed over SPI.
>
> Signed-off-by: Maxime Chevallier <maxime.chevallier@xxxxxxxxxxx>
Reviewed-by: Simon Horman <simon.horman@xxxxxxxxxxxx>