ravb: Add max_rx_len to struct ravb_hw_info

The maximum descriptor size that can be specified on the reception side for
R-Car is 2048 bytes, whereas for RZ/G2L it is 8096.

Add the max_rx_len variable to struct ravb_hw_info for allocating different
RX skb buffer sizes for R-Car and RZ/G2L using the netdev_alloc_skb
function.
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/renesas/ravb.h

@@ -990,6 +990,7 @@ enum ravb_chip_id {
 
 struct ravb_hw_info {
 	enum ravb_chip_id chip_id;
+	size_t max_rx_len;
 	unsigned aligned_tx: 1;
 };
 

drivers/net/ethernet/renesas/ravb_main.c

@@ -339,6 +339,7 @@ static void ravb_ring_format(struct net_device *ndev, int q)
 static int ravb_ring_init(struct net_device *ndev, int q)
 {
 	struct ravb_private *priv = netdev_priv(ndev);
+	const struct ravb_hw_info *info = priv->info;
 	unsigned int num_tx_desc = priv->num_tx_desc;
 	unsigned int ring_size;
 	struct sk_buff *skb;
@@ -353,7 +354,7 @@ static int ravb_ring_init(struct net_device *ndev, int q)
 		goto error;
 
 	for (i = 0; i < priv->num_rx_ring[q]; i++) {
-		skb = netdev_alloc_skb(ndev, RX_BUF_SZ + RAVB_ALIGN - 1);
+		skb = netdev_alloc_skb(ndev, info->max_rx_len);
 		if (!skb)
 			goto error;
 		ravb_set_buffer_align(skb);
@@ -535,6 +536,7 @@ static void ravb_rx_csum(struct sk_buff *skb)
 static bool ravb_rx(struct net_device *ndev, int *quota, int q)
 {
 	struct ravb_private *priv = netdev_priv(ndev);
+	const struct ravb_hw_info *info = priv->info;
 	int entry = priv->cur_rx[q] % priv->num_rx_ring[q];
 	int boguscnt = (priv->dirty_rx[q] + priv->num_rx_ring[q]) -
 			priv->cur_rx[q];
@@ -619,9 +621,7 @@ static bool ravb_rx(struct net_device *ndev, int *quota, int q)
 		desc->ds_cc = cpu_to_le16(RX_BUF_SZ);
 
 		if (!priv->rx_skb[q][entry]) {
-			skb = netdev_alloc_skb(ndev,
-					       RX_BUF_SZ +
-					       RAVB_ALIGN - 1);
+			skb = netdev_alloc_skb(ndev, info->max_rx_len);
 			if (!skb)
 				break;	/* Better luck next round. */
 			ravb_set_buffer_align(skb);
@@ -1926,10 +1926,12 @@ static int ravb_mdio_release(struct ravb_private *priv)
 
 static const struct ravb_hw_info ravb_gen3_hw_info = {
 	.chip_id = RCAR_GEN3,
+	.max_rx_len = RX_BUF_SZ + RAVB_ALIGN - 1,
 };
 
 static const struct ravb_hw_info ravb_gen2_hw_info = {
 	.chip_id = RCAR_GEN2,
+	.max_rx_len = RX_BUF_SZ + RAVB_ALIGN - 1,
 	.aligned_tx = 1,
 };