[PATCH net-next v2 2/3] net: dsa: bcm_sf2: Propagate ethtool::rxnfc to CPU port

[Florian Fainelli <f.fainelli@gmail.com>]

Allow propagating ethtool::rxnfc programming to the CPU/management port
such that it is possible for such a CPU to perform e.g: Wake-on-LAN
using filters configured by the switch. We need a tiny bit of
cooperation between the switch drivers which is able to do the full flow
matching, whereas the CPU/management port might not. The CPU/management
driver needs to return -EOPNOTSUPP to indicate an non critical error,
any other error code otherwise.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
---
 drivers/net/dsa/bcm_sf2_cfp.c | 43 ++++++++++++++++++++++++++++++++---
 1 file changed, 40 insertions(+), 3 deletions(-)

diff --git a/drivers/net/dsa/bcm_sf2_cfp.c b/drivers/net/dsa/bcm_sf2_cfp.c
index 1e37b65aab93..47c5f272a084 100644
--- a/drivers/net/dsa/bcm_sf2_cfp.c
+++ b/drivers/net/dsa/bcm_sf2_cfp.c
@@ -732,6 +732,8 @@ static int bcm_sf2_cfp_rule_set(struct dsa_switch *ds, int port,
 				struct ethtool_rx_flow_spec *fs)
 {
 	struct bcm_sf2_priv *priv = bcm_sf2_to_priv(ds);
+	s8 cpu_port = ds->ports[port].cpu_dp->index;
+	__u64 ring_cookie = fs->ring_cookie;
 	unsigned int queue_num, port_num;
 	int ret = -EINVAL;
 
@@ -748,13 +750,19 @@ static int bcm_sf2_cfp_rule_set(struct dsa_switch *ds, int port,
 	    fs->location > bcm_sf2_cfp_rule_size(priv))
 		return -EINVAL;
 
+	/* This rule is a Wake-on-LAN filter and we must specifically
+	 * target the CPU port in order for it to be working.
+	 */
+	if (ring_cookie == RX_CLS_FLOW_WAKE)
+		ring_cookie = cpu_port * SF2_NUM_EGRESS_QUEUES;
+
 	/* We do not support discarding packets, check that the
 	 * destination port is enabled and that we are within the
 	 * number of ports supported by the switch
 	 */
-	port_num = fs->ring_cookie / SF2_NUM_EGRESS_QUEUES;
+	port_num = ring_cookie / SF2_NUM_EGRESS_QUEUES;
 
-	if (fs->ring_cookie == RX_CLS_FLOW_DISC ||
+	if (ring_cookie == RX_CLS_FLOW_DISC ||
 	    !(dsa_is_user_port(ds, port_num) ||
 	      dsa_is_cpu_port(ds, port_num)) ||
 	    port_num >= priv->hw_params.num_ports)
@@ -763,7 +771,7 @@ static int bcm_sf2_cfp_rule_set(struct dsa_switch *ds, int port,
 	 * We have a small oddity where Port 6 just does not have a
 	 * valid bit here (so we substract by one).
 	 */
-	queue_num = fs->ring_cookie % SF2_NUM_EGRESS_QUEUES;
+	queue_num = ring_cookie % SF2_NUM_EGRESS_QUEUES;
 	if (port_num >= 7)
 		port_num -= 1;
 
@@ -1188,6 +1196,7 @@ static int bcm_sf2_cfp_rule_get_all(struct bcm_sf2_priv *priv,
 int bcm_sf2_get_rxnfc(struct dsa_switch *ds, int port,
 		      struct ethtool_rxnfc *nfc, u32 *rule_locs)
 {
+	struct net_device *p = ds->ports[port].cpu_dp->master;
 	struct bcm_sf2_priv *priv = bcm_sf2_to_priv(ds);
 	int ret = 0;
 
@@ -1214,12 +1223,23 @@ int bcm_sf2_get_rxnfc(struct dsa_switch *ds, int port,
 
 	mutex_unlock(&priv->cfp.lock);
 
+	if (ret)
+		return ret;
+
+	/* Pass up the commands to the attached master network device */
+	if (p->ethtool_ops->get_rxnfc) {
+		ret = p->ethtool_ops->get_rxnfc(p, nfc, rule_locs);
+		if (ret == -EOPNOTSUPP)
+			ret = 0;
+	}
+
 	return ret;
 }
 
 int bcm_sf2_set_rxnfc(struct dsa_switch *ds, int port,
 		      struct ethtool_rxnfc *nfc)
 {
+	struct net_device *p = ds->ports[port].cpu_dp->master;
 	struct bcm_sf2_priv *priv = bcm_sf2_to_priv(ds);
 	int ret = 0;
 
@@ -1240,6 +1260,23 @@ int bcm_sf2_set_rxnfc(struct dsa_switch *ds, int port,
 
 	mutex_unlock(&priv->cfp.lock);
 
+	if (ret)
+		return ret;
+
+	/* Pass up the commands to the attached master network device.
+	 * This can fail, so rollback the operation if we need to.
+	 */
+	if (p->ethtool_ops->set_rxnfc) {
+		ret = p->ethtool_ops->set_rxnfc(p, nfc);
+		if (ret && ret != -EOPNOTSUPP) {
+			mutex_lock(&priv->cfp.lock);
+			bcm_sf2_cfp_rule_del(priv, port, nfc->fs.location);
+			mutex_unlock(&priv->cfp.lock);
+		} else {
+			ret = 0;
+		}
+	}
+
 	return ret;
 }
 
-- 
2.17.1