net: mscc: ocelot: Add support for MRP

Add basic support for MRP. The HW will just trap all MRP frames on the
ring ports to CPU and allow the SW to process them. In this way it is
possible to for this node to behave both as MRM and MRC.

Current limitations are:
- it doesn't support Interconnect roles.
- it supports only a single ring.
- the HW should be able to do forwarding of MRP Test frames so the SW
  will not need to do this. So it would be able to have the role MRC
  without SW support.

Signed-off-by: Horatiu Vultur <horatiu.vultur@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 9 insertions, 1 deletions

diff --git a/drivers/net/ethernet/mscc/ocelot.c b/drivers/net/ethernet/mscc/ocelot.c
index 5d13087c85d6..46e5c9136bac 100644
--- a/drivers/net/ethernet/mscc/ocelot.c
+++ b/drivers/net/ethernet/mscc/ocelot.c
@@ -687,7 +687,7 @@ static int ocelot_xtr_poll_xfh(struct ocelot *ocelot, int grp, u32 *xfh)
 int ocelot_xtr_poll_frame(struct ocelot *ocelot, int grp, struct sk_buff **nskb)
 {
 	struct skb_shared_hwtstamps *shhwtstamps;
-	u64 tod_in_ns, full_ts_in_ns;
+	u64 tod_in_ns, full_ts_in_ns, cpuq;
 	u64 timestamp, src_port, len;
 	u32 xfh[OCELOT_TAG_LEN / 4];
 	struct net_device *dev;
@@ -704,6 +704,7 @@ int ocelot_xtr_poll_frame(struct ocelot *ocelot, int grp, struct sk_buff **nskb)
 	ocelot_xfh_get_src_port(xfh, &src_port);
 	ocelot_xfh_get_len(xfh, &len);
 	ocelot_xfh_get_rew_val(xfh, &timestamp);
+	ocelot_xfh_get_cpuq(xfh, &cpuq);
 
 	if (WARN_ON(src_port >= ocelot->num_phys_ports))
 		return -EINVAL;
@@ -770,6 +771,13 @@ int ocelot_xtr_poll_frame(struct ocelot *ocelot, int grp, struct sk_buff **nskb)
 		skb->offload_fwd_mark = 1;
 
 	skb->protocol = eth_type_trans(skb, dev);
+
+#if IS_ENABLED(CONFIG_BRIDGE_MRP)
+	if (skb->protocol == cpu_to_be16(ETH_P_MRP) &&
+	    cpuq & BIT(OCELOT_MRP_CPUQ))
+		skb->offload_fwd_mark = 0;
+#endif
+
 	*nskb = skb;
 
 	return 0;