net: mscc: ocelot: export a constant for the tag length in bytes

This constant will be used in a future patch to increase the MTU on NPI
ports, and will also be used in the tagger driver for Felix.
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mscc/ocelot.c

@@ -576,11 +576,11 @@ static int ocelot_port_xmit(struct sk_buff *skb, struct net_device *dev)
 	struct skb_shared_info *shinfo = skb_shinfo(skb);
 	struct ocelot_port *ocelot_port = &priv->port;
 	struct ocelot *ocelot = ocelot_port->ocelot;
+	u32 val, ifh[OCELOT_TAG_LEN / 4];
 	struct frame_info info = {};
 	u8 grp = 0; /* Send everything on CPU group 0 */
 	unsigned int i, count, last;
 	int port = priv->chip_port;
-	u32 val, ifh[IFH_LEN];
 
 	val = ocelot_read(ocelot, QS_INJ_STATUS);
 	if (!(val & QS_INJ_STATUS_FIFO_RDY(BIT(grp))) ||
@@ -603,7 +603,7 @@ static int ocelot_port_xmit(struct sk_buff *skb, struct net_device *dev)
 
 	ocelot_gen_ifh(ifh, &info);
 
-	for (i = 0; i < IFH_LEN; i++)
+	for (i = 0; i < OCELOT_TAG_LEN / 4; i++)
 		ocelot_write_rix(ocelot, (__force u32)cpu_to_be32(ifh[i]),
 				 QS_INJ_WR, grp);
 

drivers/net/ethernet/mscc/ocelot.h

@@ -43,8 +43,6 @@
 
 #define OCELOT_PTP_QUEUE_SZ	128
 
-#define IFH_LEN 4
-
 struct frame_info {
 	u32 len;
 	u16 port;
@@ -66,6 +64,8 @@ struct frame_info {
 #define IFH_REW_OP_TWO_STEP_PTP		0x3
 #define IFH_REW_OP_ORIGIN_PTP		0x5
 
+#define OCELOT_TAG_LEN			16
+
 #define OCELOT_SPEED_2500 0
 #define OCELOT_SPEED_1000 1
 #define OCELOT_SPEED_100  2

drivers/net/ethernet/mscc/ocelot_board.c

@@ -105,7 +105,7 @@ static irqreturn_t ocelot_xtr_irq_handler(int irq, void *arg)
 		int sz, len, buf_len;
 		struct sk_buff *skb;
 
-		for (i = 0; i < IFH_LEN; i++) {
+		for (i = 0; i < OCELOT_TAG_LEN / 4; i++) {
 			err = ocelot_rx_frame_word(ocelot, grp, true, &ifh[i]);
 			if (err != 4)
 				break;