net: dpaa: Adjust queue depth on rate change

Instead of setting the queue depth once during probe, adjust it on the
fly whenever we configure the link. This is a bit unusal, since usually
the DPAA driver calls into the FMAN driver, but here we do the opposite.
We need to add a netdev to struct mac_device for this, but it will soon
live in the phylink config.

I haven't tested this extensively, but it doesn't seem to break
anything. We could possibly optimize this a bit by keeping track of the
last rate, but for now we just update every time. 10GEC probably doesn't
need to call into this at all, but I've added it for consistency.

Signed-off-by: Sean Anderson <sean.anderson@seco.com>
Acked-by: Camelia Groza <camelia.groza@nxp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 34 insertions, 4 deletions

diff --git a/drivers/net/ethernet/freescale/dpaa/dpaa_eth.c b/drivers/net/ethernet/freescale/dpaa/dpaa_eth.c
index 7df3bf5a9c03..0a180d17121c 100644
--- a/drivers/net/ethernet/freescale/dpaa/dpaa_eth.c
+++ b/drivers/net/ethernet/freescale/dpaa/dpaa_eth.c
@@ -197,6 +197,8 @@ static int dpaa_rx_extra_headroom;
 #define dpaa_get_max_mtu()	\
 	(dpaa_max_frm - (VLAN_ETH_HLEN + ETH_FCS_LEN))
 
+static void dpaa_eth_cgr_set_speed(struct mac_device *mac_dev, int speed);
+
 static int dpaa_netdev_init(struct net_device *net_dev,
 			    const struct net_device_ops *dpaa_ops,
 			    u16 tx_timeout)
@@ -262,6 +264,9 @@ static int dpaa_netdev_init(struct net_device *net_dev,
 	net_dev->needed_headroom = priv->tx_headroom;
 	net_dev->watchdog_timeo = msecs_to_jiffies(tx_timeout);
 
+	mac_dev->net_dev = net_dev;
+	mac_dev->update_speed = dpaa_eth_cgr_set_speed;
+
 	/* start without the RUNNING flag, phylib controls it later */
 	netif_carrier_off(net_dev);
 
@@ -826,10 +831,10 @@ static int dpaa_eth_cgr_init(struct dpaa_priv *priv)
 	initcgr.we_mask = cpu_to_be16(QM_CGR_WE_CSCN_EN | QM_CGR_WE_CS_THRES);
 	initcgr.cgr.cscn_en = QM_CGR_EN;
 
-	/* Set different thresholds based on the MAC speed.
-	 * This may turn suboptimal if the MAC is reconfigured at a speed
-	 * lower than its max, e.g. if a dTSEC later negotiates a 100Mbps link.
-	 * In such cases, we ought to reconfigure the threshold, too.
+	/* Set different thresholds based on the configured MAC speed.
+	 * This may turn suboptimal if the MAC is reconfigured at another
+	 * speed, so MACs must call dpaa_eth_cgr_set_speed in their adjust_link
+	 * callback.
 	 */
 	if (priv->mac_dev->if_support & SUPPORTED_10000baseT_Full)
 		cs_th = DPAA_CS_THRESHOLD_10G;
@@ -858,6 +863,31 @@ out_error:
 	return err;
 }
 
+static void dpaa_eth_cgr_set_speed(struct mac_device *mac_dev, int speed)
+{
+	struct net_device *net_dev = mac_dev->net_dev;
+	struct dpaa_priv *priv = netdev_priv(net_dev);
+	struct qm_mcc_initcgr opts = { };
+	u32 cs_th;
+	int err;
+
+	opts.we_mask = cpu_to_be16(QM_CGR_WE_CS_THRES);
+	switch (speed) {
+	case SPEED_10000:
+		cs_th = DPAA_CS_THRESHOLD_10G;
+		break;
+	case SPEED_1000:
+	default:
+		cs_th = DPAA_CS_THRESHOLD_1G;
+		break;
+	}
+	qm_cgr_cs_thres_set64(&opts.cgr.cs_thres, cs_th, 1);
+
+	err = qman_update_cgr_safe(&priv->cgr_data.cgr, &opts);
+	if (err)
+		netdev_err(net_dev, "could not update speed: %d\n", err);
+}
+
 static inline void dpaa_setup_ingress(const struct dpaa_priv *priv,
 				      struct dpaa_fq *fq,
 				      const struct qman_fq *template)