Re: [PATCH net-next v4] net: dsa: microchip: Add SGMII port support to KSZ9477 switch

[ALOK TIWARI <alok.a.tiwari@oracle.com>]

On 16-05-2025 08:11, Tristram.Ha@microchip.com wrote:
> +static int ksz9477_pcs_write(struct mii_bus *bus, int phy, int mmd, int reg,
> +			     u16 val)
> +{
> +	struct ksz_device *dev = bus->priv;
> +	int port = ksz_get_sgmii_port(dev);
> +
> +	if (mmd == MDIO_MMD_VEND2) {
> +		struct ksz_port *p = &dev->ports[port];
> +
> +		if (reg == MMD_SR_MII_AUTO_NEG_CTRL) {
> +			u16 sgmii_mode = SR_MII_PCS_SGMII << SR_MII_PCS_MODE_S;
> +
> +			/* Need these bits for 1000BASE-X mode to work with
> +			 * AN on.
> +			 */
> +			if (!(val & sgmii_mode))
> +				val |= SR_MII_SGMII_LINK_UP |
> +				       SR_MII_TX_CFG_PHY_MASTER;
> +
> +			/* SGMII interrupt in the port cannot be masked, so
> +			 * make sure interrupt is not enabled as it is not
> +			 * handled.
> +			 */
> +			val &= ~SR_MII_AUTO_NEG_COMPLETE_INTR;
> +		} else if (reg == MII_BMCR) {
> +			/* The MII_ADVERTISE register needs to write once
> +			 * before doing auto-negotiation for the correct
> +			 * config_word to be sent out after reset.
> +			 */
> +			if ((val & BMCR_ANENABLE) && !p->sgmii_adv_write) {
> +				u16 adv;
> +
> +				/* The SGMII port cannot disable flow contrl

typo contrl -> control

> +				 * so it is better to just advertise symmetric
> +				 * pause.
> +				 */
> +				port_sgmii_r(dev, port, mmd, MII_ADVERTISE,
> +					     &adv);
> +				adv |= ADVERTISE_1000XPAUSE;
> +				adv &= ~ADVERTISE_1000XPSE_ASYM;
> +				port_sgmii_w(dev, port, mmd, MII_ADVERTISE,
> +					     adv);
> +				p->sgmii_adv_write = 1;
> +			} else if (val & BMCR_RESET) {
> +				p->sgmii_adv_write = 0;
> +			}
> +		} else if (reg == MII_ADVERTISE) {
> +			/* XPCS driver writes to this register so there is no
> +			 * need to update it for the errata.
> +			 */
> +			p->sgmii_adv_write = 1;
> +		}
> +	}
> +	port_sgmii_w(dev, port, mmd, reg, val);

a '\n' before return, Apply in other relevant locations as well.

> +	return 0;
> +}


Thanks,
Alok