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 27d651a80f3f32f6458645ad2fc6a778537a859c..55cbf65512c3bafb4780f6166e6d05ba5f314603 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 4304072bd3c536e852a38cf6c37716df8500ed66..3efc897c991310c637353aaed01c9516575a02d9 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,