Subject: Re: [PATCH net-next v2 3/3] dpaa2-eth: Add pause frame support

From: Andrew Lunn <[email-masked]>
Date: Wed, 28 Aug 2019 01:21:32 +0200

On Tue, Aug 27, 2019 at 05:15:51PM +0300, Ioana Radulescu wrote:
> Starting with firmware version MC10.18.0, we have support for
> L2 flow control. Asymmetrical configuration (Rx or Tx only) is
> supported, but not pause frame autonegotioation.

> +static int set_pause(struct dpaa2_eth_priv *priv)
> +{
> +	struct device *dev = priv->net_dev->dev.parent;
> +	struct dpni_link_cfg link_cfg = {0};
> +	int err;
> +
> +	/* Get the default link options so we don't override other flags */
> +	err = dpni_get_link_cfg(priv->mc_io, 0, priv->mc_token, &link_cfg);
> +	if (err) {
> +		dev_err(dev, "dpni_get_link_cfg() failed\n");
> +		return err;
> +	}
> +
> +	link_cfg.options |= DPNI_LINK_OPT_PAUSE;
> +	link_cfg.options &= ~DPNI_LINK_OPT_ASYM_PAUSE;
> +	err = dpni_set_link_cfg(priv->mc_io, 0, priv->mc_token, &link_cfg);
> +	if (err) {
> +		dev_err(dev, "dpni_set_link_cfg() failed\n");
> +		return err;
> +	}
> +
> +	priv->link_state.options = link_cfg.options;
> +
> +	return 0;
> +}
> +
>  /* Configure the DPNI object this interface is associated with */
>  static int setup_dpni(struct fsl_mc_device *ls_dev)
>  {
> @@ -2500,6 +2562,13 @@ static int setup_dpni(struct fsl_mc_device *ls_dev)
>  
>  	set_enqueue_mode(priv);
>  
> +	/* Enable pause frame support */
> +	if (dpaa2_eth_has_pause_support(priv)) {
> +		err = set_pause(priv);
> +		if (err)
> +			goto close;

Hi Ioana

So by default you have the MAC do pause, not asym pause?  Generally,
any MAC that can do asym pause does asym pause.

But if this is what you want, it is not wrong.

Reviewed-by: Andrew Lunn <[email-masked]>

    Andrew