net: sxgbe: add Checksum offload support for Samsung sxgbe

This patch adds TX and RX checksum offload support.

Signed-off-by: Vipul Pandya <vipul.pandya@samsung.com>
Neatening-by: Joe Perches <joe@perches.com>
Signed-off-by: Byungho An <bh74.an@samsung.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

4 files changed, 61 insertions, 12 deletions

diff --git a/drivers/net/ethernet/samsung/sxgbe/sxgbe_common.h b/drivers/net/ethernet/samsung/sxgbe/sxgbe_common.h
index 7293c4c14be8..4893cfd298a7 100644
--- a/drivers/net/ethernet/samsung/sxgbe/sxgbe_common.h
+++ b/drivers/net/ethernet/samsung/sxgbe/sxgbe_common.h
@@ -340,6 +340,10 @@ struct sxgbe_core_ops {
         void (*set_eee_timer)(void __iomem *ioaddr, const int ls,
                               const int tw);
         void (*set_eee_pls)(void __iomem *ioaddr, const int link);
+
+        /* Enable disable checksum offload operations */
+        void (*enable_rx_csum)(void __iomem *ioaddr);
+        void (*disable_rx_csum)(void __iomem *ioaddr);
 };
 
 const struct sxgbe_core_ops *sxgbe_get_core_ops(void);
@@ -452,6 +456,7 @@ struct sxgbe_priv_data {
         struct sxgbe_ops *hw;   /* sxgbe specific ops */
         int no_csum_insertion;
         int irq;
+        int rxcsum_insertion;
         spinlock_t stats_lock;  /* lock for tx/rx statatics */
 
         struct phy_device *phydev;
diff --git a/drivers/net/ethernet/samsung/sxgbe/sxgbe_core.c b/drivers/net/ethernet/samsung/sxgbe/sxgbe_core.c
index 01647901f55f..66d4a74a137c 100644
--- a/drivers/net/ethernet/samsung/sxgbe/sxgbe_core.c
+++ b/drivers/net/ethernet/samsung/sxgbe/sxgbe_core.c
@@ -218,6 +218,24 @@ static void  sxgbe_set_eee_timer(void __iomem *ioaddr,
         writel(value, ioaddr + SXGBE_CORE_LPI_TIMER_CTRL);
 }
 
+static void sxgbe_enable_rx_csum(void __iomem *ioaddr)
+{
+        u32 ctrl;
+
+        ctrl = readl(ioaddr + SXGBE_CORE_RX_CONFIG_REG);
+        ctrl |= SXGBE_RX_CSUMOFFLOAD_ENABLE;
+        writel(ctrl, ioaddr + SXGBE_CORE_RX_CONFIG_REG);
+}
+
+static void sxgbe_disable_rx_csum(void __iomem *ioaddr)
+{
+        u32 ctrl;
+
+        ctrl = readl(ioaddr + SXGBE_CORE_RX_CONFIG_REG);
+        ctrl &= ~SXGBE_RX_CSUMOFFLOAD_ENABLE;
+        writel(ctrl, ioaddr + SXGBE_CORE_RX_CONFIG_REG);
+}
+
 const struct sxgbe_core_ops core_ops = {
         .core_init              = sxgbe_core_init,
         .dump_regs              = sxgbe_core_dump_regs,
@@ -234,6 +252,8 @@ const struct sxgbe_core_ops core_ops = {
         .reset_eee_mode         = sxgbe_reset_eee_mode,
         .set_eee_timer          = sxgbe_set_eee_timer,
         .set_eee_pls            = sxgbe_set_eee_pls,
+        .enable_rx_csum         = sxgbe_enable_rx_csum,
+        .disable_rx_csum        = sxgbe_disable_rx_csum,
 };
 
 const struct sxgbe_core_ops *sxgbe_get_core_ops(void)
diff --git a/drivers/net/ethernet/samsung/sxgbe/sxgbe_desc.h b/drivers/net/ethernet/samsung/sxgbe/sxgbe_desc.h
index 6d44b9faf64e..838cb9fb0ea9 100644
--- a/drivers/net/ethernet/samsung/sxgbe/sxgbe_desc.h
+++ b/drivers/net/ethernet/samsung/sxgbe/sxgbe_desc.h
@@ -113,7 +113,7 @@ struct sxgbe_rx_norm_desc {
                         /* WB RDES3 */
                         u32 pkt_len:14;
                         u32 rdes3_reserved:1;
-                        u32 err_summary:15;
+                        u32 err_summary:1;
                         u32 err_l2_type:4;
                         u32 layer34_pkt_type:4;
                         u32 no_coagulation_pkt:1;
diff --git a/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c b/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c
index dc0249bfa03b..96b4b2c25b16 100644
--- a/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c
+++ b/drivers/net/ethernet/samsung/sxgbe/sxgbe_main.c
@@ -1252,6 +1252,7 @@ void sxgbe_tso_prepare(struct sxgbe_priv_data *priv,
 static netdev_tx_t sxgbe_xmit(struct sk_buff *skb, struct net_device *dev)
 {
         unsigned int entry, frag_num;
+        int cksum_flag = 0;
         struct netdev_queue *dev_txq;
         unsigned txq_index = skb_get_queue_mapping(skb);
         struct sxgbe_priv_data *priv = netdev_priv(dev);
@@ -1332,7 +1333,7 @@ static netdev_tx_t sxgbe_xmit(struct sk_buff *skb, struct net_device *dev)
                                            __func__);
 
                         priv->hw->desc->prepare_tx_desc(tx_desc, 1, no_pagedlen,
-                                                        no_pagedlen, 0);
+                                                        no_pagedlen, cksum_flag);
                 }
         }
 
@@ -1350,7 +1351,7 @@ static netdev_tx_t sxgbe_xmit(struct sk_buff *skb, struct net_device *dev)
 
                 /* prepare the descriptor */
                 priv->hw->desc->prepare_tx_desc(tx_desc, 0, len,
-                                                len, 0);
+                                                len, cksum_flag);
                 /* memory barrier to flush descriptor */
                 wmb();
 
@@ -1471,6 +1472,8 @@ static int sxgbe_rx(struct sxgbe_priv_data *priv, int limit)
         unsigned int entry = priv->rxq[qnum]->cur_rx;
         unsigned int next_entry = 0;
         unsigned int count = 0;
+        int checksum;
+        int status;
 
         while (count < limit) {
                 struct sxgbe_rx_norm_desc *p;
@@ -1487,7 +1490,18 @@ static int sxgbe_rx(struct sxgbe_priv_data *priv, int limit)
                 next_entry = (++priv->rxq[qnum]->cur_rx) % rxsize;
                 prefetch(priv->rxq[qnum]->dma_rx + next_entry);
 
-                /*TO DO read the status of the incoming frame */
+                /* Read the status of the incoming frame and also get checksum
+                 * value based on whether it is enabled in SXGBE hardware or
+                 * not.
+                 */
+                status = priv->hw->desc->rx_wbstatus(p, &priv->xstats,
+                                                     &checksum);
+                if (unlikely(status < 0)) {
+                        entry = next_entry;
+                        continue;
+                }
+                if (unlikely(!priv->rxcsum_insertion))
+                        checksum = CHECKSUM_NONE;
 
                 skb = priv->rxq[qnum]->rx_skbuff[entry];
 
@@ -1501,7 +1515,11 @@ static int sxgbe_rx(struct sxgbe_priv_data *priv, int limit)
 
                 skb_put(skb, frame_len);
 
-                netif_receive_skb(skb);
+                skb->ip_summed = checksum;
+                if (checksum == CHECKSUM_NONE)
+                        netif_receive_skb(skb);
+                else
+                        napi_gro_receive(&priv->napi, skb);
 
                 entry = next_entry;
         }
@@ -1748,15 +1766,15 @@ static int sxgbe_set_features(struct net_device *dev,
 {
         struct sxgbe_priv_data *priv = netdev_priv(dev);
         netdev_features_t changed = dev->features ^ features;
-        u32 ctrl;
 
         if (changed & NETIF_F_RXCSUM) {
-                ctrl = readl(priv->ioaddr + SXGBE_CORE_RX_CONFIG_REG);
-                if (features & NETIF_F_RXCSUM)
-                        ctrl |= SXGBE_RX_CSUMOFFLOAD_ENABLE;
-                else
-                        ctrl &= ~SXGBE_RX_CSUMOFFLOAD_ENABLE;
-                writel(ctrl, priv->ioaddr + SXGBE_CORE_RX_CONFIG_REG);
+                if (features & NETIF_F_RXCSUM) {
+                        priv->hw->mac->enable_rx_csum(priv->ioaddr);
+                        priv->rxcsum_insertion = true;
+                } else {
+                        priv->hw->mac->disable_rx_csum(priv->ioaddr);
+                        priv->rxcsum_insertion = false;
+                }
         }
 
         return 0;
@@ -2115,6 +2133,12 @@ struct sxgbe_priv_data *sxgbe_drv_probe(struct device *device,
                 }
         }
 
+        /* Enable Rx checksum offload */
+        if (priv->hw_cap.rx_csum_offload) {
+                priv->hw->mac->enable_rx_csum(priv->ioaddr);
+                priv->rxcsum_insertion = true;
+        }
+
         /* Rx Watchdog is available, enable depend on platform data */
         if (!priv->plat->riwt_off) {
                 priv->use_riwt = 1;