summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorDeepak Sikri <deepak.sikri@st.com>2012-07-08 21:14:45 +0000
committerDavid S. Miller <davem@davemloft.net>2012-07-09 14:37:51 -0700
commit8e83989106562326bfd6aaf92174fe138efd026b (patch)
tree9561ae1bf2f7468a730eac175fd0d6e8475f92f5
parentc1109736bcdd14b590392e9a96d66e7e823f9e67 (diff)
downloadop-kernel-dev-8e83989106562326bfd6aaf92174fe138efd026b.zip
op-kernel-dev-8e83989106562326bfd6aaf92174fe138efd026b.tar.gz
stmmac: Fix for nfs hang on multiple reboot
It was observed that during multiple reboots nfs hangs. The status of receive descriptors shows that all the descriptors were in control of CPU, and none were assigned to DMA. Also the DMA status register confirmed that the Rx buffer is unavailable. This patch adds the fix for the same by adding the memory barriers to ascertain that the all instructions before enabling the Rx or Tx DMA are completed which involves the proper setting of the ownership bit in DMA descriptors. Signed-off-by: Deepak Sikri <deepak.sikri@st.com> Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r--drivers/net/ethernet/stmicro/stmmac/stmmac_main.c3
1 files changed, 3 insertions, 0 deletions
diff --git a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
index 51b3b68..ea3003e 100644
--- a/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
+++ b/drivers/net/ethernet/stmicro/stmmac/stmmac_main.c
@@ -1212,6 +1212,7 @@ static netdev_tx_t stmmac_xmit(struct sk_buff *skb, struct net_device *dev)
priv->hw->desc->prepare_tx_desc(desc, 0, len, csum_insertion);
wmb();
priv->hw->desc->set_tx_owner(desc);
+ wmb();
}
/* Interrupt on completition only for the latest segment */
@@ -1227,6 +1228,7 @@ static netdev_tx_t stmmac_xmit(struct sk_buff *skb, struct net_device *dev)
/* To avoid raise condition */
priv->hw->desc->set_tx_owner(first);
+ wmb();
priv->cur_tx++;
@@ -1290,6 +1292,7 @@ static inline void stmmac_rx_refill(struct stmmac_priv *priv)
}
wmb();
priv->hw->desc->set_rx_owner(p + entry);
+ wmb();
}
}
OpenPOWER on IntegriCloud