Re: [PATCH v3 2/5] net: macb: add support for sgmii MAC-PHY interface

[Russell King - ARM Linux admin]

On Fri, Jun 21, 2019 at 09:34:50AM +0100, Parshuram Thombare wrote:
> @@ -486,23 +503,54 @@ static void gem_mac_config(struct phylink_config *pl_config, unsigned int mode,
>  {
>  	struct net_device *netdev = to_net_dev(pl_config->dev);
>  	struct macb *bp = netdev_priv(netdev);
> +	bool change_interface = bp->phy_interface != state->interface;
>  	unsigned long flags;
>  
>  	spin_lock_irqsave(&bp->lock, flags);
>  
> +	if (change_interface) {
> +		if (bp->phy_interface == PHY_INTERFACE_MODE_SGMII ||
> +		    bp->phy_interface == PHY_INTERFACE_MODE_1000BASEX ||
> +		    bp->phy_interface == PHY_INTERFACE_MODE_2500BASEX) {
> +			gem_writel(bp, NCFGR, ~GEM_BIT(SGMIIEN) &
> +				   ~GEM_BIT(PCSSEL) &
> +				   gem_readl(bp, NCFGR));
> +			gem_writel(bp, NCR, ~GEM_BIT(TWO_PT_FIVE_GIG) &
> +				   gem_readl(bp, NCR));
> +			gem_writel(bp, PCS_CTRL, gem_readl(bp, PCS_CTRL) |
> +				   GEM_BIT(PCS_CTRL_RST));
> +		}
> +		bp->phy_interface = state->interface;
> +	}
> +
>  	if (!phylink_autoneg_inband(mode) &&
>  	    (bp->speed != state->speed ||
> -	     bp->duplex != state->duplex)) {
> +	     bp->duplex != state->duplex ||
> +	     change_interface)) {
>  		u32 reg;
>  
>  		reg = macb_readl(bp, NCFGR);
>  		reg &= ~(MACB_BIT(SPD) | MACB_BIT(FD));
>  		if (macb_is_gem(bp))
>  			reg &= ~GEM_BIT(GBE);
> +		macb_or_gem_writel(bp, NCFGR, reg);
> +
> +		if (bp->phy_interface == PHY_INTERFACE_MODE_SGMII ||
> +		    bp->phy_interface == PHY_INTERFACE_MODE_1000BASEX ||
> +		    bp->phy_interface == PHY_INTERFACE_MODE_2500BASEX)
> +			gem_writel(bp, NCFGR, GEM_BIT(SGMIIEN) |
> +				   GEM_BIT(PCSSEL) |
> +				   gem_readl(bp, NCFGR));

You don't appear to treat SGMII any differently from the 802.3z modes.
They are certainly not the same thing, so this doesn't seem to be
correct.  Also, placing this here, I don't see how the MAC gets
configured for SGMII if in-band mode is enabled.

> +
> +		reg = macb_readl(bp, NCFGR);
>  		if (state->duplex)
>  			reg |= MACB_BIT(FD);
>  
>  		switch (state->speed) {
> +		case SPEED_2500:
> +			gem_writel(bp, NCR, GEM_BIT(TWO_PT_FIVE_GIG) |
> +				   gem_readl(bp, NCR));
> +			break;
>  		case SPEED_1000:
>  			reg |= GEM_BIT(GBE);
>  			break;

-- 
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