net: netcp: use hw capability to remove FCS word from rx packets

Some of the newer Ethernet switch hw (such as that on k2e/l/g) can
strip the Etherenet FCS from packet at the port 0 egress of the switch.
So use this capability instead of doing it in software.

Signed-off-by: Murali Karicheri <m-karicheri2@ti.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/ti/netcp.h b/drivers/net/ethernet/ti/netcp.h
index d243c5d..8900a6f 100644 (file)
--- a/drivers/net/ethernet/ti/netcp.h
+++ b/drivers/net/ethernet/ti/netcp.h
@@ -102,6 +102,8 @@ struct netcp_intf {
        void                    *rx_fdq[KNAV_DMA_FDQ_PER_CHAN];
        struct napi_struct      rx_napi;
        struct napi_struct      tx_napi;
+#define ETH_SW_CAN_REMOVE_ETH_FCS      BIT(0)
+       u32                     hw_cap;
 
        /* 64-bit netcp stats */
        struct netcp_stats      stats;

diff --git a/drivers/net/ethernet/ti/netcp_core.c b/drivers/net/ethernet/ti/netcp_core.c
index b077ed4..68a75cc 100644 (file)
--- a/drivers/net/ethernet/ti/netcp_core.c
+++ b/drivers/net/ethernet/ti/netcp_core.c
@@ -739,8 +739,12 @@ static int netcp_process_one_rx_packet(struct netcp_intf *netcp)
                dev_dbg(netcp->ndev_dev, "mismatch in packet size(%d) & sum of fragments(%d)\n",
                        pkt_sz, accum_sz);
 
-       /* Remove ethernet FCS from the packet */
-       __pskb_trim(skb, skb->len - ETH_FCS_LEN);
+       /* Newer version of the Ethernet switch can trim the Ethernet FCS
+        * from the packet and is indicated in hw_cap. So trim it only for
+        * older h/w
+        */
+       if (!(netcp->hw_cap & ETH_SW_CAN_REMOVE_ETH_FCS))
+               __pskb_trim(skb, skb->len - ETH_FCS_LEN);
 
        /* Call each of the RX hooks */
        p_info.skb = skb;

diff --git a/drivers/net/ethernet/ti/netcp_ethss.c b/drivers/net/ethernet/ti/netcp_ethss.c
index 4a64b3e..6bb8e26 100644 (file)
--- a/drivers/net/ethernet/ti/netcp_ethss.c
+++ b/drivers/net/ethernet/ti/netcp_ethss.c
@@ -122,6 +122,7 @@
 #define MACSL_FULLDUPLEX                       BIT(0)
 
 #define GBE_CTL_P0_ENABLE                      BIT(2)
+#define ETH_SW_CTL_P0_TX_CRC_REMOVE            BIT(13)
 #define GBE13_REG_VAL_STAT_ENABLE_ALL          0xff
 #define XGBE_REG_VAL_STAT_ENABLE_ALL           0xf
 #define GBE_STATS_CD_SEL                       BIT(28)
@@ -2821,7 +2822,7 @@ static int gbe_open(void *intf_priv, struct net_device *ndev)
        struct netcp_intf *netcp = netdev_priv(ndev);
        struct gbe_slave *slave = gbe_intf->slave;
        int port_num = slave->port_num;
-       u32 reg;
+       u32 reg, val;
        int ret;
 
        reg = readl(GBE_REG_ADDR(gbe_dev, switch_regs, id_ver));
@@ -2851,7 +2852,12 @@ static int gbe_open(void *intf_priv, struct net_device *ndev)
        writel(0, GBE_REG_ADDR(gbe_dev, switch_regs, ptype));
 
        /* Control register */
-       writel(GBE_CTL_P0_ENABLE, GBE_REG_ADDR(gbe_dev, switch_regs, control));
+       val = GBE_CTL_P0_ENABLE;
+       if (IS_SS_ID_MU(gbe_dev)) {
+               val |= ETH_SW_CTL_P0_TX_CRC_REMOVE;
+               netcp->hw_cap = ETH_SW_CAN_REMOVE_ETH_FCS;
+       }
+       writel(val, GBE_REG_ADDR(gbe_dev, switch_regs, control));
 
        /* All statistics enabled and STAT AB visible by default */
        writel(gbe_dev->stats_en_mask, GBE_REG_ADDR(gbe_dev, switch_regs,