nfp: flower: turn on recirc and merge hint support in firmware

Write to a FW symbol to indicate that the driver supports flow merging. If
this symbol does not exist then flow merging and recirculation is not
supported on the FW. If support is available, add a stub to deal with FW
to kernel merge hint messages.

Full flow merging requires the firmware to support of flow mods. If it
does not, then do not attempt to 'turn on' flow merging.

Signed-off-by: John Hurley <john.hurley@netronome.com>
Signed-off-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/netronome/nfp/flower/cmsg.c

@@ -222,6 +222,10 @@ nfp_flower_cmsg_process_one_rx(struct nfp_app *app, struct sk_buff *skb)
 	case NFP_FLOWER_CMSG_TYPE_PORT_MOD:
 		nfp_flower_cmsg_portmod_rx(app, skb);
 		break;
+	case NFP_FLOWER_CMSG_TYPE_MERGE_HINT:
+		if (app_priv->flower_ext_feats & NFP_FL_FEATS_FLOW_MERGE)
+			break;
+		goto err_default;
 	case NFP_FLOWER_CMSG_TYPE_NO_NEIGH:
 		nfp_tunnel_request_route(app, skb);
 		break;
@@ -235,6 +239,7 @@ nfp_flower_cmsg_process_one_rx(struct nfp_app *app, struct sk_buff *skb)
 		}
 		/* fall through */
 	default:
+err_default:
 		nfp_flower_cmsg_warn(app, "Cannot handle invalid repr control type %u\n",
 				     type);
 		goto out;

drivers/net/ethernet/netronome/nfp/flower/cmsg.h

@@ -407,6 +407,7 @@ enum nfp_flower_cmsg_type_port {
 	NFP_FLOWER_CMSG_TYPE_PORT_REIFY =	6,
 	NFP_FLOWER_CMSG_TYPE_MAC_REPR =		7,
 	NFP_FLOWER_CMSG_TYPE_PORT_MOD =		8,
+	NFP_FLOWER_CMSG_TYPE_MERGE_HINT =	9,
 	NFP_FLOWER_CMSG_TYPE_NO_NEIGH =		10,
 	NFP_FLOWER_CMSG_TYPE_TUN_MAC =		11,
 	NFP_FLOWER_CMSG_TYPE_ACTIVE_TUNS =	12,

drivers/net/ethernet/netronome/nfp/flower/main.c

@@ -641,11 +641,28 @@ static int nfp_flower_init(struct nfp_app *app)
 		goto err_cleanup_metadata;
 	}
 
+	if (app_priv->flower_ext_feats & NFP_FL_FEATS_FLOW_MOD) {
+		/* Tell the firmware that the driver supports flow merging. */
+		err = nfp_rtsym_write_le(app->pf->rtbl,
+					 "_abi_flower_merge_hint_enable", 1);
+		if (!err)
+			app_priv->flower_ext_feats |= NFP_FL_FEATS_FLOW_MERGE;
+		else if (err == -ENOENT)
+			nfp_warn(app->cpp, "Flow merge not supported by FW.\n");
+		else
+			goto err_lag_clean;
+	} else {
+		nfp_warn(app->cpp, "Flow mod/merge not supported by FW.\n");
+	}
+
 	INIT_LIST_HEAD(&app_priv->indr_block_cb_priv);
 	INIT_LIST_HEAD(&app_priv->non_repr_priv);
 
 	return 0;
 
+err_lag_clean:
+	if (app_priv->flower_ext_feats & NFP_FL_FEATS_LAG)
+		nfp_flower_lag_cleanup(&app_priv->nfp_lag);
 err_cleanup_metadata:
 	nfp_flower_metadata_cleanup(app);
 err_free_app_priv:

drivers/net/ethernet/netronome/nfp/flower/main.h

@@ -39,6 +39,8 @@ struct nfp_app;
 #define NFP_FL_NBI_MTU_SETTING		BIT(1)
 #define NFP_FL_FEATS_GENEVE_OPT		BIT(2)
 #define NFP_FL_FEATS_VLAN_PCP		BIT(3)
+#define NFP_FL_FEATS_FLOW_MOD		BIT(5)
+#define NFP_FL_FEATS_FLOW_MERGE		BIT(30)
 #define NFP_FL_FEATS_LAG		BIT(31)
 
 struct nfp_fl_mask_id {