Re: [PATCH net-next v15 5/6] net: dsa: mv88e6xxx: Add support for mv88e6393x family of Marvell

["Marek Behún" <kabel@kernel.org>]

On Tue, 12 Jan 2021 20:54:04 +0100
Marek Behún <kabel@kernel.org> wrote:

> +	/* mv88e6393x family errata 3.7 :
> +	 * When changing cmode on SERDES port from any other mode to 1000BASE-X
> +	 * mode the link may not come up due to invalid 1000BASE-X
> +	 * advertisement.
> +	 * Workaround: Correct advertisement and reset PHY core.
> +	 */
> +	if (cmode == MV88E6XXX_PORT_STS_CMODE_1000BASEX) {
> +		reg = MV88E6390_SGMII_ANAR_1000BASEX_FD;
> +		err = mv88e6390_serdes_write(chip, lane, MDIO_MMD_PHYXS,
> +					     MV88E6390_SGMII_ANAR, reg);
> +		if (err)
> +			return err;
> +
> +		/* soft reset the PCS/PMA */
> +		err = mv88e6390_serdes_read(chip, lane, MDIO_MMD_PHYXS,
> +					    MV88E6390_SGMII_CONTROL, &reg);
> +		if (err)
> +			return err;
> +
> +		reg |= MV88E6390_SGMII_CONTROL_RESET;
> +		err = mv88e6390_serdes_write(chip, lane, MDIO_MMD_PHYXS,
> +					     MV88E6390_SGMII_CONTROL, reg);
> +		if (err)
> +			return err;

It would seem that this is already done in
mv88e6390_serdes_pcs_config, just without the last reset.

> +#define MV88E6390_SGMII_STATUS_AN_ABLE	BIT(3)
> +#define MV88E6390_SGMII_ANAR	0x2004
> +#define MV88E6390_SGMII_ANAR_1000BASEX_FD	BIT(5)
> +#define MV88E6390_SGMII_CONTROL		0x2000

This register is already called MV88E6390_SGMII_BMCR and the bits are
defined as BMCR_* macros. Thse same for MV88E6390_SGMII_STATUS and
MV88E6390_SGMII_ANAR.

> +#define MV88E6390_SGMII_CONTROL_RESET		BIT(15)
> +#define MV88E6390_SGMII_CONTROL_LOOPBACK	BIT(14)
> +#define MV88E6390_SGMII_CONTROL_PDOWN		BIT(11)
> +#define MV88E6390_SGMII_STATUS		0x2001

I shall fix this in another version.