nfp: flower: check for/turn on LAG support in firmware

Check if the fw contains the _abi_flower_balance_sync_enable symbol. If it
does then write a 1 to this indicating that the driver is willing to
receive NIC to kernel LAG related control messages.

If the write is successful, update the list of extra features supported by
the fw and add a stub to accept LAG cmsgs.
Signed-off-by: John Hurley <john.hurley@netronome.com>
Reviewed-by: Pieter Jansen van Vuuren <pieter.jansenvanvuuren@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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

@@ -239,6 +239,7 @@ nfp_flower_cmsg_portreify_rx(struct nfp_app *app, struct sk_buff *skb)
 static void
 nfp_flower_cmsg_process_one_rx(struct nfp_app *app, struct sk_buff *skb)
 {
+	struct nfp_flower_priv *app_priv = app->priv;
 	struct nfp_flower_cmsg_hdr *cmsg_hdr;
 	enum nfp_flower_cmsg_type_port type;
 
@@ -258,6 +259,10 @@ nfp_flower_cmsg_process_one_rx(struct nfp_app *app, struct sk_buff *skb)
 	case NFP_FLOWER_CMSG_TYPE_ACTIVE_TUNS:
 		nfp_tunnel_keep_alive(app, skb);
 		break;
+	case NFP_FLOWER_CMSG_TYPE_LAG_CONFIG:
+		if (app_priv->flower_ext_feats & NFP_FL_FEATS_LAG)
+			break;
+		/* fall through */
 	default:
 		nfp_flower_cmsg_warn(app, "Cannot handle invalid repr control type %u\n",
 				     type);

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

@@ -366,6 +366,7 @@ struct nfp_flower_cmsg_hdr {
 enum nfp_flower_cmsg_type_port {
 	NFP_FLOWER_CMSG_TYPE_FLOW_ADD =		0,
 	NFP_FLOWER_CMSG_TYPE_FLOW_DEL =		2,
+	NFP_FLOWER_CMSG_TYPE_LAG_CONFIG =	4,
 	NFP_FLOWER_CMSG_TYPE_PORT_REIFY =	6,
 	NFP_FLOWER_CMSG_TYPE_MAC_REPR =		7,
 	NFP_FLOWER_CMSG_TYPE_PORT_MOD =		8,

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

@@ -546,8 +546,20 @@ static int nfp_flower_init(struct nfp_app *app)
 	else
 		app_priv->flower_ext_feats = features;
 
+	/* Tell the firmware that the driver supports lag. */
+	err = nfp_rtsym_write_le(app->pf->rtbl,
+				 "_abi_flower_balance_sync_enable", 1);
+	if (!err)
+		app_priv->flower_ext_feats |= NFP_FL_FEATS_LAG;
+	else if (err == -ENOENT)
+		nfp_warn(app->cpp, "LAG not supported by FW.\n");
+	else
+		goto err_cleanup_metadata;
+
 	return 0;
 
+err_cleanup_metadata:
+	nfp_flower_metadata_cleanup(app);
 err_free_app_priv:
 	vfree(app->priv);
 	return err;

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

@@ -67,6 +67,7 @@ struct nfp_app;
 /* Extra features bitmap. */
 #define NFP_FL_FEATS_GENEVE		BIT(0)
 #define NFP_FL_NBI_MTU_SETTING		BIT(1)
+#define NFP_FL_FEATS_LAG		BIT(31)
 
 struct nfp_fl_mask_id {
 	struct circ_buf mask_id_free_list;