net: sh_eth: fix the rxdesc pointer when rx descriptor empty happens

When Receive Descriptor Empty happens, rxdesc pointer of the driver
and actual next descriptor of the controller may be mismatch.
This patch fixes it.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/renesas/sh_eth.c b/drivers/net/ethernet/renesas/sh_eth.c
index be3c22179161504f39eb2527b85cfa44eb2da685..667169b825263d96402b44ba22784a1696f80c82 100644 (file)
--- a/drivers/net/ethernet/renesas/sh_eth.c
+++ b/drivers/net/ethernet/renesas/sh_eth.c
@@ -1101,8 +1101,12 @@ static int sh_eth_rx(struct net_device *ndev)
 
        /* Restart Rx engine if stopped. */
        /* If we don't need to check status, don't. -KDU */
-       if (!(sh_eth_read(ndev, EDRRR) & EDRRR_R))
+       if (!(sh_eth_read(ndev, EDRRR) & EDRRR_R)) {
+               /* fix the values for the next receiving */
+               mdp->cur_rx = mdp->dirty_rx = (sh_eth_read(ndev, RDFAR) -
+                                              sh_eth_read(ndev, RDLAR)) >> 4;
                sh_eth_write(ndev, EDRRR_R, EDRRR);
+       }
 
        return 0;
 }
@@ -1199,8 +1203,6 @@ static void sh_eth_error(struct net_device *ndev, int intr_status)
                /* Receive Descriptor Empty int */
                ndev->stats.rx_over_errors++;
 
-               if (sh_eth_read(ndev, EDRRR) ^ EDRRR_R)
-                       sh_eth_write(ndev, EDRRR_R, EDRRR);
                if (netif_msg_rx_err(mdp))
                        dev_err(&ndev->dev, "Receive Descriptor Empty\n");
        }