r8169: honor jumbo settings when chipset is requested to start.

Some hardware start settings implicitely assume an usual 1500 bytes mtu
that can't be guaranteed because changes of mtu may be requested both
before and after the hardware is started.
Reported-by: Tomi Orava <tomimo@ncircle.nullnet.fi>
Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Cc: Hayes Wang <hayeswang@realtek.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/realtek/r8169.c

@@ -4765,8 +4765,10 @@ static void rtl_hw_start_8168bb(struct rtl8169_private *tp)
 
 	RTL_W16(CPlusCmd, RTL_R16(CPlusCmd) & ~R8168_CPCMD_QUIRK_MASK);
 
-	rtl_tx_performance_tweak(pdev,
-		(0x5 << MAX_READ_REQUEST_SHIFT) | PCI_EXP_DEVCTL_NOSNOOP_EN);
+	if (tp->dev->mtu <= ETH_DATA_LEN) {
+		rtl_tx_performance_tweak(pdev, (0x5 << MAX_READ_REQUEST_SHIFT) |
+					 PCI_EXP_DEVCTL_NOSNOOP_EN);
+	}
 }
 
 static void rtl_hw_start_8168bef(struct rtl8169_private *tp)
@@ -4789,7 +4791,8 @@ static void __rtl_hw_start_8168cp(struct rtl8169_private *tp)
 
 	RTL_W8(Config3, RTL_R8(Config3) & ~Beacon_en);
 
-	rtl_tx_performance_tweak(pdev, 0x5 << MAX_READ_REQUEST_SHIFT);
+	if (tp->dev->mtu <= ETH_DATA_LEN)
+		rtl_tx_performance_tweak(pdev, 0x5 << MAX_READ_REQUEST_SHIFT);
 
 	rtl_disable_clock_request(pdev);
 
@@ -4822,7 +4825,8 @@ static void rtl_hw_start_8168cp_2(struct rtl8169_private *tp)
 
 	RTL_W8(Config3, RTL_R8(Config3) & ~Beacon_en);
 
-	rtl_tx_performance_tweak(pdev, 0x5 << MAX_READ_REQUEST_SHIFT);
+	if (tp->dev->mtu <= ETH_DATA_LEN)
+		rtl_tx_performance_tweak(pdev, 0x5 << MAX_READ_REQUEST_SHIFT);
 
 	RTL_W16(CPlusCmd, RTL_R16(CPlusCmd) & ~R8168_CPCMD_QUIRK_MASK);
 }
@@ -4841,7 +4845,8 @@ static void rtl_hw_start_8168cp_3(struct rtl8169_private *tp)
 
 	RTL_W8(MaxTxPacketSize, TxPacketMax);
 
-	rtl_tx_performance_tweak(pdev, 0x5 << MAX_READ_REQUEST_SHIFT);
+	if (tp->dev->mtu <= ETH_DATA_LEN)
+		rtl_tx_performance_tweak(pdev, 0x5 << MAX_READ_REQUEST_SHIFT);
 
 	RTL_W16(CPlusCmd, RTL_R16(CPlusCmd) & ~R8168_CPCMD_QUIRK_MASK);
 }
@@ -4901,7 +4906,8 @@ static void rtl_hw_start_8168d(struct rtl8169_private *tp)
 
 	RTL_W8(MaxTxPacketSize, TxPacketMax);
 
-	rtl_tx_performance_tweak(pdev, 0x5 << MAX_READ_REQUEST_SHIFT);
+	if (tp->dev->mtu <= ETH_DATA_LEN)
+		rtl_tx_performance_tweak(pdev, 0x5 << MAX_READ_REQUEST_SHIFT);
 
 	RTL_W16(CPlusCmd, RTL_R16(CPlusCmd) & ~R8168_CPCMD_QUIRK_MASK);
 }
@@ -4913,7 +4919,8 @@ static void rtl_hw_start_8168dp(struct rtl8169_private *tp)
 
 	rtl_csi_access_enable_1(tp);
 
-	rtl_tx_performance_tweak(pdev, 0x5 << MAX_READ_REQUEST_SHIFT);
+	if (tp->dev->mtu <= ETH_DATA_LEN)
+		rtl_tx_performance_tweak(pdev, 0x5 << MAX_READ_REQUEST_SHIFT);
 
 	RTL_W8(MaxTxPacketSize, TxPacketMax);
 
@@ -4972,7 +4979,8 @@ static void rtl_hw_start_8168e_1(struct rtl8169_private *tp)
 
 	rtl_ephy_init(tp, e_info_8168e_1, ARRAY_SIZE(e_info_8168e_1));
 
-	rtl_tx_performance_tweak(pdev, 0x5 << MAX_READ_REQUEST_SHIFT);
+	if (tp->dev->mtu <= ETH_DATA_LEN)
+		rtl_tx_performance_tweak(pdev, 0x5 << MAX_READ_REQUEST_SHIFT);
 
 	RTL_W8(MaxTxPacketSize, TxPacketMax);
 
@@ -4998,7 +5006,8 @@ static void rtl_hw_start_8168e_2(struct rtl8169_private *tp)
 
 	rtl_ephy_init(tp, e_info_8168e_2, ARRAY_SIZE(e_info_8168e_2));
 
-	rtl_tx_performance_tweak(pdev, 0x5 << MAX_READ_REQUEST_SHIFT);
+	if (tp->dev->mtu <= ETH_DATA_LEN)
+		rtl_tx_performance_tweak(pdev, 0x5 << MAX_READ_REQUEST_SHIFT);
 
 	rtl_eri_write(tp, 0xc0, ERIAR_MASK_0011, 0x0000, ERIAR_EXGMAC);
 	rtl_eri_write(tp, 0xb8, ERIAR_MASK_0011, 0x0000, ERIAR_EXGMAC);