1 files changed, 70 insertions, 0 deletions

diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index 332b19c645b4..dc09f9a8a49b 100644
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -10,6 +10,7 @@
 
 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
 #include <linux/clk.h>
+#include <linux/crc32.h>
 #include <linux/module.h>
 #include <linux/moduleparam.h>
 #include <linux/kernel.h>
@@ -1565,6 +1566,9 @@ static unsigned int macb_tx_map(struct macb *bp,
                 if (i == queue->tx_head) {
                         ctrl |= MACB_BF(TX_LSO, lso_ctrl);
                         ctrl |= MACB_BF(TX_TCP_SEQ_SRC, seq_ctrl);
+                        if ((bp->dev->features & NETIF_F_HW_CSUM) &&
+                            skb->ip_summed != CHECKSUM_PARTIAL && !lso_ctrl)
+                                ctrl |= MACB_BIT(TX_NOCRC);
                 } else
                         /* Only set MSS/MFS on payload descriptors
                          * (second or later descriptor)
@@ -1651,6 +1655,67 @@ static inline int macb_clear_csum(struct sk_buff *skb)
         return 0;
 }
 
+static int macb_pad_and_fcs(struct sk_buff **skb, struct net_device *ndev)
+{
+        bool cloned = skb_cloned(*skb) || skb_header_cloned(*skb);
+        int padlen = ETH_ZLEN - (*skb)->len;
+        int headroom = skb_headroom(*skb);
+        int tailroom = skb_tailroom(*skb);
+        struct sk_buff *nskb;
+        u32 fcs;
+
+        if (!(ndev->features & NETIF_F_HW_CSUM) ||
+            !((*skb)->ip_summed != CHECKSUM_PARTIAL) ||
+            skb_shinfo(*skb)->gso_size) /* Not available for GSO */
+                return 0;
+
+        if (padlen <= 0) {
+                /* FCS could be appeded to tailroom. */
+                if (tailroom >= ETH_FCS_LEN)
+                        goto add_fcs;
+                /* FCS could be appeded by moving data to headroom. */
+                else if (!cloned && headroom + tailroom >= ETH_FCS_LEN)
+                        padlen = 0;
+                /* No room for FCS, need to reallocate skb. */
+                else
+                        padlen = ETH_FCS_LEN - tailroom;
+        } else {
+                /* Add room for FCS. */
+                padlen += ETH_FCS_LEN;
+        }
+
+        if (!cloned && headroom + tailroom >= padlen) {
+                (*skb)->data = memmove((*skb)->head, (*skb)->data, (*skb)->len);
+                skb_set_tail_pointer(*skb, (*skb)->len);
+        } else {
+                nskb = skb_copy_expand(*skb, 0, padlen, GFP_ATOMIC);
+                if (!nskb)
+                        return -ENOMEM;
+
+                dev_kfree_skb_any(*skb);
+                *skb = nskb;
+        }
+
+        if (padlen) {
+                if (padlen >= ETH_FCS_LEN)
+                        skb_put_zero(*skb, padlen - ETH_FCS_LEN);
+                else
+                        skb_trim(*skb, ETH_FCS_LEN - padlen);
+        }
+
+add_fcs:
+        /* set FCS to packet */
+        fcs = crc32_le(~0, (*skb)->data, (*skb)->len);
+        fcs = ~fcs;
+
+        skb_put_u8(*skb, fcs            & 0xff);
+        skb_put_u8(*skb, (fcs >> 8)     & 0xff);
+        skb_put_u8(*skb, (fcs >> 16)    & 0xff);
+        skb_put_u8(*skb, (fcs >> 24)    & 0xff);
+
+        return 0;
+}
+
 static netdev_tx_t macb_start_xmit(struct sk_buff *skb, struct net_device *dev)
 {
         u16 queue_index = skb_get_queue_mapping(skb);
@@ -1667,6 +1732,11 @@ static netdev_tx_t macb_start_xmit(struct sk_buff *skb, struct net_device *dev)
                 return ret;
         }
 
+        if (macb_pad_and_fcs(&skb, dev)) {
+                dev_kfree_skb_any(skb);
+                return ret;
+        }
+
         is_lso = (skb_shinfo(skb)->gso_size != 0);
 
         if (is_lso) {