r8169: disable tx interrupt coalescing on RTL8168

In contrast to switching rx irq coalescing off what fixed an issue,
switching tx irq coalescing off is merely a latency optimization,
therefore net-next. As part of this change:

- Remove INTT_0 .. INTT_3 constants, they aren't used.

- Remove comment in rtl_hw_start_8169(), we now have a detailed
  description by the code in rtl_set_coalesce().

- Due to switching irq coalescing off per default we don't need the
  initialization in rtl_hw_start_8168(). If ethtool is used to switch
  on coalescing then rtl_set_coalesce() will configure this register.

For the sake of completeness: This patch just changes the default.
Users still have the option to configure irq coalescing via ethtool.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/realtek/r8169.c b/drivers/net/ethernet/realtek/r8169.c
index 88eb9e05d2a18c541eb62b95697ccbc0578acaa8..71f848e6e1ec8aaea43831efc03a4a35f874f1a3 100644 (file)
--- a/drivers/net/ethernet/realtek/r8169.c
+++ b/drivers/net/ethernet/realtek/r8169.c
@@ -490,10 +490,6 @@ enum rtl_register_content {
        PCIDAC          = (1 << 4),
        PCIMulRW        = (1 << 3),
 #define INTT_MASK      GENMASK(1, 0)
-       INTT_0          = 0x0000,       // 8168
-       INTT_1          = 0x0001,       // 8168
-       INTT_2          = 0x0002,       // 8168
-       INTT_3          = 0x0003,       // 8168
 
        /* rtl8169_PHYstatus */
        TBI_Enable      = 0x80,
@@ -4702,6 +4698,8 @@ static void rtl_hw_start(struct  rtl8169_private *tp)
        rtl_set_rx_tx_desc_registers(tp);
        rtl_lock_config_regs(tp);
 
+       /* disable interrupt coalescing */
+       RTL_W16(tp, IntrMitigate, 0x0000);
        /* Initially a 10 us delay. Turned it into a PCI commit. - FR */
        RTL_R8(tp, IntrMask);
        RTL_W8(tp, ChipCmd, CmdTxEnb | CmdRxEnb);
@@ -4734,12 +4732,6 @@ static void rtl_hw_start_8169(struct rtl8169_private *tp)
 
        rtl8169_set_magic_reg(tp, tp->mac_version);
 
-       /*
-        * Undocumented corner. Supposedly:
-        * (TxTimer << 12) | (TxPackets << 8) | (RxTimer << 4) | RxPackets
-        */
-       RTL_W16(tp, IntrMitigate, 0x0000);
-
        RTL_W32(tp, RxMissed, 0);
 }
 
@@ -5456,12 +5448,6 @@ static void rtl_hw_start_8168(struct rtl8169_private *tp)
 {
        RTL_W8(tp, MaxTxPacketSize, TxPacketMax);
 
-       tp->cp_cmd &= ~INTT_MASK;
-       tp->cp_cmd |= PktCntrDisable | INTT_1;
-       RTL_W16(tp, CPlusCmd, tp->cp_cmd);
-
-       RTL_W16(tp, IntrMitigate, 0x5100);
-
        /* Work around for RxFIFO overflow. */
        if (tp->mac_version == RTL_GIGA_MAC_VER_11) {
                tp->irq_mask |= RxFIFOOver;
@@ -5749,8 +5735,6 @@ static void rtl_hw_start_8101(struct rtl8169_private *tp)
                rtl_hw_start_8168h_1(tp);
                break;
        }
-
-       RTL_W16(tp, IntrMitigate, 0x0000);
 }
 
 static int rtl8169_change_mtu(struct net_device *dev, int new_mtu)