jme: Fix FIFO flush issue

Set the RX FIFO flush watermark lower.
According to Federico and JMicron's reply,
setting it to 16QW would be stable on most platforms.
Otherwise, user might experience packet drop issue.

CC: stable@kernel.org
Reported-by: Federico Quagliata <federico@quagliata.org>
Fixed-by: Federico Quagliata <federico@quagliata.org>
Signed-off-by: Guo-Fu Tseng <cooldavid@cooldavid.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/jme.c b/drivers/net/ethernet/jme.c
index 27d651a..55cbf65 100644 (file)
--- a/drivers/net/ethernet/jme.c
+++ b/drivers/net/ethernet/jme.c
@@ -2328,19 +2328,11 @@ jme_change_mtu(struct net_device *netdev, int new_mtu)
                ((new_mtu) < IPV6_MIN_MTU))
                return -EINVAL;
 
-       if (new_mtu > 4000) {
-               jme->reg_rxcs &= ~RXCS_FIFOTHNP;
-               jme->reg_rxcs |= RXCS_FIFOTHNP_64QW;
-               jme_restart_rx_engine(jme);
-       } else {
-               jme->reg_rxcs &= ~RXCS_FIFOTHNP;
-               jme->reg_rxcs |= RXCS_FIFOTHNP_128QW;
-               jme_restart_rx_engine(jme);
-       }
 
        netdev->mtu = new_mtu;
        netdev_update_features(netdev);
 
+       jme_restart_rx_engine(jme);
        jme_reset_link(jme);
 
        return 0;

diff --git a/drivers/net/ethernet/jme.h b/drivers/net/ethernet/jme.h
index 4304072..3efc897 100644 (file)
--- a/drivers/net/ethernet/jme.h
+++ b/drivers/net/ethernet/jme.h
@@ -730,7 +730,7 @@ enum jme_rxcs_values {
        RXCS_RETRYCNT_60        = 0x00000F00,
 
        RXCS_DEFAULT            = RXCS_FIFOTHTP_128T |
-                                 RXCS_FIFOTHNP_128QW |
+                                 RXCS_FIFOTHNP_16QW |
                                  RXCS_DMAREQSZ_128B |
                                  RXCS_RETRYGAP_256ns |
                                  RXCS_RETRYCNT_32,