X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=blobdiff_plain;f=drivers%2Fnet%2Fethernet%2Fcadence%2Fmacb_main.c;h=4508f0d150da95d8e838d0ead806e8ef74794cc5;hb=f822e9c4ffa511a5c681cf866287d9383a3b6f1b;hp=7a2fe63d1136877b1ab0fad1297c0b2e3259b107;hpb=7f879e1a94ac99586abf0659c03f35c1e48279c4;p=linux.git

diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index 7a2fe63d1136..4508f0d150da 100644
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -73,7 +73,11 @@ struct sifive_fu540_macb_mgmt {
 /* Max length of transmit frame must be a multiple of 8 bytes */
 #define MACB_TX_LEN_ALIGN	8
 #define MACB_MAX_TX_LEN		((unsigned int)((1 << MACB_TX_FRMLEN_SIZE) - 1) & ~((unsigned int)(MACB_TX_LEN_ALIGN - 1)))
-#define GEM_MAX_TX_LEN		((unsigned int)((1 << GEM_TX_FRMLEN_SIZE) - 1) & ~((unsigned int)(MACB_TX_LEN_ALIGN - 1)))
+/* Limit maximum TX length as per Cadence TSO errata. This is to avoid a
+ * false amba_error in TX path from the DMA assuming there is not enough
+ * space in the SRAM (16KB) even when there is.
+ */
+#define GEM_MAX_TX_LEN		(unsigned int)(0x3FC0)
 
 #define GEM_MTU_MIN_SIZE	ETH_MIN_MTU
 #define MACB_NETIF_LSO		NETIF_F_TSO
@@ -1791,16 +1795,14 @@ static netdev_features_t macb_features_check(struct sk_buff *skb,
 
 	/* Validate LSO compatibility */
 
-	/* there is only one buffer */
-	if (!skb_is_nonlinear(skb))
+	/* there is only one buffer or protocol is not UDP */
+	if (!skb_is_nonlinear(skb) || (ip_hdr(skb)->protocol != IPPROTO_UDP))
 		return features;
 
 	/* length of header */
 	hdrlen = skb_transport_offset(skb);
-	if (ip_hdr(skb)->protocol == IPPROTO_TCP)
-		hdrlen += tcp_hdrlen(skb);
 
-	/* For LSO:
+	/* For UFO only:
 	 * When software supplies two or more payload buffers all payload buffers
 	 * apart from the last must be a multiple of 8 bytes in size.
 	 */