enet: fec: fix fail resume from suspend state

Without this patch
1. boot with nfs (no_console_suspend)
2. echo mem >/sys/power/state
3. wakeup by wakesource
4. print "eth0: tx queue full"

This fix above problem by reinit bd queue at restart function

Signed-off-by: Frank Li <Frank.Li@freescale.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 50 insertions, 32 deletions

diff --git a/drivers/net/ethernet/freescale/fec.c b/drivers/net/ethernet/freescale/fec.c
index 911d0253dbb2..f292c3aa423f 100644
--- a/drivers/net/ethernet/freescale/fec.c
+++ b/drivers/net/ethernet/freescale/fec.c
@@ -345,6 +345,53 @@ fec_enet_start_xmit(struct sk_buff *skb, struct net_device *ndev)
         return NETDEV_TX_OK;
 }
 
+/* Init RX & TX buffer descriptors
+ */
+static void fec_enet_bd_init(struct net_device *dev)
+{
+        struct fec_enet_private *fep = netdev_priv(dev);
+        struct bufdesc *bdp;
+        unsigned int i;
+
+        /* Initialize the receive buffer descriptors. */
+        bdp = fep->rx_bd_base;
+        for (i = 0; i < RX_RING_SIZE; i++) {
+
+                /* Initialize the BD for every fragment in the page. */
+                if (bdp->cbd_bufaddr)
+                        bdp->cbd_sc = BD_ENET_RX_EMPTY;
+                else
+                        bdp->cbd_sc = 0;
+                bdp = fec_enet_get_nextdesc(bdp, fep->bufdesc_ex);
+        }
+
+        /* Set the last buffer to wrap */
+        bdp = fec_enet_get_prevdesc(bdp, fep->bufdesc_ex);
+        bdp->cbd_sc |= BD_SC_WRAP;
+
+        fep->cur_rx = fep->rx_bd_base;
+
+        /* ...and the same for transmit */
+        bdp = fep->tx_bd_base;
+        fep->cur_tx = bdp;
+        for (i = 0; i < TX_RING_SIZE; i++) {
+
+                /* Initialize the BD for every fragment in the page. */
+                bdp->cbd_sc = 0;
+                if (bdp->cbd_bufaddr && fep->tx_skbuff[i]) {
+                        dev_kfree_skb_any(fep->tx_skbuff[i]);
+                        fep->tx_skbuff[i] = NULL;
+                }
+                bdp->cbd_bufaddr = 0;
+                bdp = fec_enet_get_nextdesc(bdp, fep->bufdesc_ex);
+        }
+
+        /* Set the last buffer to wrap */
+        bdp = fec_enet_get_prevdesc(bdp, fep->bufdesc_ex);
+        bdp->cbd_sc |= BD_SC_WRAP;
+        fep->dirty_tx = bdp;
+}
+
 /* This function is called to start or restart the FEC during a link
  * change.  This only happens when switching between half and full
  * duplex.
@@ -388,6 +435,8 @@ fec_restart(struct net_device *ndev, int duplex)
         /* Set maximum receive buffer size. */
         writel(PKT_MAXBLR_SIZE, fep->hwp + FEC_R_BUFF_SIZE);
 
+        fec_enet_bd_init(ndev);
+
         /* Set receive and transmit descriptor base. */
         writel(fep->bd_dma, fep->hwp + FEC_R_DES_START);
         if (fep->bufdesc_ex)
@@ -397,7 +446,6 @@ fec_restart(struct net_device *ndev, int duplex)
                 writel((unsigned long)fep->bd_dma + sizeof(struct bufdesc)
                         * RX_RING_SIZE, fep->hwp + FEC_X_DES_START);
 
-        fep->cur_rx = fep->rx_bd_base;
 
         for (i = 0; i <= TX_RING_MOD_MASK; i++) {
                 if (fep->tx_skbuff[i]) {
@@ -1597,8 +1645,6 @@ static int fec_enet_init(struct net_device *ndev)
 {
         struct fec_enet_private *fep = netdev_priv(ndev);
         struct bufdesc *cbd_base;
-        struct bufdesc *bdp;
-        unsigned int i;
 
         /* Allocate memory for buffer descriptors. */
         cbd_base = dma_alloc_coherent(NULL, PAGE_SIZE, &fep->bd_dma,
@@ -1608,6 +1654,7 @@ static int fec_enet_init(struct net_device *ndev)
                 return -ENOMEM;
         }
 
+        memset(cbd_base, 0, PAGE_SIZE);
         spin_lock_init(&fep->hw_lock);
 
         fep->netdev = ndev;
@@ -1631,35 +1678,6 @@ static int fec_enet_init(struct net_device *ndev)
         writel(FEC_RX_DISABLED_IMASK, fep->hwp + FEC_IMASK);
         netif_napi_add(ndev, &fep->napi, fec_enet_rx_napi, FEC_NAPI_WEIGHT);
 
-        /* Initialize the receive buffer descriptors. */
-        bdp = fep->rx_bd_base;
-        for (i = 0; i < RX_RING_SIZE; i++) {
-
-                /* Initialize the BD for every fragment in the page. */
-                bdp->cbd_sc = 0;
-                bdp = fec_enet_get_nextdesc(bdp, fep->bufdesc_ex);
-        }
-
-        /* Set the last buffer to wrap */
-        bdp = fec_enet_get_prevdesc(bdp, fep->bufdesc_ex);
-        bdp->cbd_sc |= BD_SC_WRAP;
-
-        /* ...and the same for transmit */
-        bdp = fep->tx_bd_base;
-        fep->cur_tx = bdp;
-        for (i = 0; i < TX_RING_SIZE; i++) {
-
-                /* Initialize the BD for every fragment in the page. */
-                bdp->cbd_sc = 0;
-                bdp->cbd_bufaddr = 0;
-                bdp = fec_enet_get_nextdesc(bdp, fep->bufdesc_ex);
-        }
-
-        /* Set the last buffer to wrap */
-        bdp = fec_enet_get_prevdesc(bdp, fep->bufdesc_ex);
-        bdp->cbd_sc |= BD_SC_WRAP;
-        fep->dirty_tx = bdp;
-
         fec_restart(ndev, 0);
 
         return 0;