Subject: Re: [PATCH net-next v4 3/3] net: dpaa2-mac: export standard statistics

From: Jakub Kicinski <[email-masked]>
Date: Fri, 20 Mar 2026 19:19:16 -0700

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---
net: dpaa2-mac: export standard statistics

This commit adds support for exporting MAC statistics through the
standard ethtool statistics structures (rmon, eth-ctrl, eth-mac, and
pause) in the dpaa2-mac driver for both dpaa2-eth and dpaa2-switch.

> diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-ethtool.c b/drivers/net/ethernet/freescale/dpaa2/dpaa2-ethtool.c
> index baab4f1c908d..59f5c778df38 100644
> --- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-ethtool.c
> +++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-ethtool.c

[ ... ]

> @@ -962,4 +1017,8 @@ const struct ethtool_ops dpaa2_ethtool_ops = {
>  	.get_coalesce = dpaa2_eth_get_coalesce,
>  	.set_coalesce = dpaa2_eth_set_coalesce,
>  	.get_channels = dpaa2_eth_get_channels,
> +	.get_rmon_stats = dpaa2_eth_get_rmon_stats,
> +	.get_pause_stats = dpaa2_eth_get_pause_stats,
> +	.get_eth_ctrl_stats = dpaa2_eth_get_ctrl_stats,
> +	.get_eth_mac_stats = dpaa2_eth_get_eth_mac_stats,
>  };

[ ... ]

> diff --git a/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch-ethtool.c b/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch-ethtool.c
> index a888f6e6e9b0..f5d9321c7ef9 100644
> --- a/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch-ethtool.c
> +++ b/drivers/net/ethernet/freescale/dpaa2/dpaa2-switch-ethtool.c

[ ... ]

> @@ -210,6 +210,49 @@ static void dpaa2_switch_ethtool_get_stats(struct net_device *netdev,
>  	mutex_unlock(&port_priv->mac_lock);
>  }
>
> +static void
> +dpaa2_switch_get_rmon_stats(struct net_device *netdev,
> +			    struct ethtool_rmon_stats *rmon_stats,
> +			    const struct ethtool_rmon_hist_range **ranges)
> +{
> +	struct ethsw_port_priv *port_priv = netdev_priv(netdev);
> +
> +	mutex_lock(&port_priv->mac_lock);
> +
> +	if (dpaa2_switch_port_has_mac(port_priv))
> +		dpaa2_mac_get_rmon_stats(port_priv->mac, rmon_stats, ranges);
> +
> +	mutex_unlock(&port_priv->mac_lock);
> +}
> +
> +static void
> +dpaa2_switch_get_ctrl_stats(struct net_device *net_dev,
> +			    struct ethtool_eth_ctrl_stats *ctrl_stats)
> +{
> +	struct ethsw_port_priv *port_priv = netdev_priv(net_dev);
> +
> +	mutex_lock(&port_priv->mac_lock);
> +
> +	if (dpaa2_switch_port_has_mac(port_priv))
> +		dpaa2_mac_get_ctrl_stats(port_priv->mac, ctrl_stats);
> +
> +	mutex_unlock(&port_priv->mac_lock);
> +}
> +
> +static void
> +dpaa2_switch_get_eth_mac_stats(struct net_device *net_dev,
> +			       struct ethtool_eth_mac_stats *eth_mac_stats)
> +{
> +	struct ethsw_port_priv *port_priv = netdev_priv(net_dev);
> +
> +	mutex_lock(&port_priv->mac_lock);
> +
> +	if (dpaa2_switch_port_has_mac(port_priv))
> +		dpaa2_mac_get_eth_mac_stats(port_priv->mac, eth_mac_stats);
> +
> +	mutex_unlock(&port_priv->mac_lock);
> +}
> +
>  const struct ethtool_ops dpaa2_switch_port_ethtool_ops = {
>  	.get_drvinfo		= dpaa2_switch_get_drvinfo,
>  	.get_link		= ethtool_op_get_link,
> @@ -218,4 +261,7 @@ const struct ethtool_ops dpaa2_switch_port_ethtool_ops = {
>  	.get_strings		= dpaa2_switch_ethtool_get_strings,
>  	.get_ethtool_stats	= dpaa2_switch_ethtool_get_stats,
>  	.get_sset_count		= dpaa2_switch_ethtool_get_sset_count,
> +	.get_rmon_stats		= dpaa2_switch_get_rmon_stats,
> +	.get_eth_ctrl_stats	= dpaa2_switch_get_ctrl_stats,
> +	.get_eth_mac_stats	= dpaa2_switch_get_eth_mac_stats,
>  };

Is the .get_pause_stats callback missing from the dpaa2-switch driver?

The commit message states that rmon, eth-ctrl, eth-mac, and pause
statistics are exported for both dpaa2-eth and dpaa2-switch drivers.

Looking at dpaa2-ethtool.c, the dpaa2-eth driver registers all four
callbacks in dpaa2_ethtool_ops:

	.get_rmon_stats = dpaa2_eth_get_rmon_stats,
	.get_pause_stats = dpaa2_eth_get_pause_stats,
	.get_eth_ctrl_stats = dpaa2_eth_get_ctrl_stats,
	.get_eth_mac_stats = dpaa2_eth_get_eth_mac_stats,

But dpaa2_switch_port_ethtool_ops only registers three callbacks. The
underlying MAC layer function dpaa2_mac_get_pause_stats() exists and is
declared in dpaa2-mac.h.

Also, dpaa2_mac_open() allocates DMA memory for mac->pause_stats when
DPAA2_MAC_FEATURE_STANDARD_STATS is set:

drivers/net/ethernet/freescale/dpaa2/dpaa2-mac.c:dpaa2_mac_open() {
	...
	if (mac->features & DPAA2_MAC_FEATURE_STANDARD_STATS) {
		dpaa2_mac_setup_stats(mac, &mac->rmon_stats,
				      DPAA2_MAC_NUM_RMON_STATS,
				      dpaa2_mac_rmon_stats);

		dpaa2_mac_setup_stats(mac, &mac->pause_stats,
				      DPAA2_MAC_NUM_PAUSE_STATS,
				      dpaa2_mac_pause_stats);

		dpaa2_mac_setup_stats(mac, &mac->eth_ctrl_stats,
				      DPAA2_MAC_NUM_ETH_CTRL_STATS,
				      dpaa2_mac_eth_ctrl_stats);

		dpaa2_mac_setup_stats(mac, &mac->eth_mac_stats,
				      DPAA2_MAC_NUM_ETH_MAC_STATS,
				      dpaa2_mac_eth_mac_stats);
	}
	...
}

Without the .get_pause_stats callback in the switch driver, would the
pause_stats DMA resources be allocated but never used?
-- 
pw-bot: cr