Re: [PATCH net-next v3 2/2] net: mdio: add a driver for PIC64-HPSC/HX MDIO controller

Andrew Lunn
2026-03-31T12:51:32Z

On Tue, Mar 31, 2026 at 05:38:54AM -0700, Charles Perry wrote:
> This adds an MDIO driver for PIC64-HPSC/HX. The hardware supports C22
> and C45 but only C22 is implemented in this commit.
>
> This MDIO hardware is based on a Microsemi design supported in Linux by
> mdio-mscc-miim.c. However, The register interface is completely
> different with pic64hpsc, hence the need for a separate driver.
>
> The documentation recommends an input clock of 156.25MHz and a prescaler
> of 39, which yields an MDIO clock of 1.95MHz.
>
> The hardware supports an interrupt pin or a "TRIGGER" bit that can be
> polled to signal transaction completion. This commit uses polling.
>
> This was tested on Microchip HB1301 evalkit with a VSC8574 and a
> VSC8541.
>
> Signed-off-by: Charles Perry <charles.perry@microchip.com>
> Reviewed-by: Maxime Chevallier <maxime.chevallier@bootlin.com>

Reviewed-by: Andrew Lunn <andrew@lunn.ch>

Andrew