[PATCH net] r8169: fix jumbo packet handling on resume from suspend

[Heiner Kallweit]

Mariusz reported that invalid packets are sent after resume from
suspend if jumbo packets are active. It turned out that his BIOS
resets chip settings to non-jumbo on resume. Most chip settings are
re-initialized on resume from suspend by calling rtl_hw_start(),
so let's add configuring jumbo to this function.
There's nothing wrong with the commit marked as fixed, it's just
the first one where the patch applies cleanly.

Fixes: 7366016d2d4c ("r8169: read common register for PCI commit")
Reported-by: Mariusz Bialonczyk <ma...@skyboo.net>
Tested-by: Mariusz Bialonczyk <ma...@skyboo.net>
Signed-off-by: Heiner Kallweit <hkallwe...@gmail.com>
---
 drivers/net/ethernet/realtek/r8169_main.c | 35 +++++++----------------
 1 file changed, 11 insertions(+), 24 deletions(-)

diff --git a/drivers/net/ethernet/realtek/r8169_main.c 
b/drivers/net/ethernet/realtek/r8169_main.c
index 74f81fe03..350b0d949 100644
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -4146,6 +4146,14 @@ static void rtl_hw_jumbo_disable(struct rtl8169_private 
*tp)
        rtl_lock_config_regs(tp);
 }
 
+static void rtl_jumbo_config(struct rtl8169_private *tp, int mtu)
+{
+       if (mtu > ETH_DATA_LEN)
+               rtl_hw_jumbo_enable(tp);
+       else
+               rtl_hw_jumbo_disable(tp);
+}
+
 DECLARE_RTL_COND(rtl_chipcmd_cond)
 {
        return RTL_R8(tp, ChipCmd) & CmdReset;
@@ -4442,11 +4450,6 @@ static void rtl8168g_set_pause_thresholds(struct 
rtl8169_private *tp,
 static void rtl_hw_start_8168bb(struct rtl8169_private *tp)
 {
        RTL_W8(tp, Config3, RTL_R8(tp, Config3) & ~Beacon_en);
-
-       if (tp->dev->mtu <= ETH_DATA_LEN) {
-               rtl_tx_performance_tweak(tp, PCI_EXP_DEVCTL_READRQ_4096B |
-                                        PCI_EXP_DEVCTL_NOSNOOP_EN);
-       }
 }
 
 static void rtl_hw_start_8168bef(struct rtl8169_private *tp)
@@ -4462,9 +4465,6 @@ static void __rtl_hw_start_8168cp(struct rtl8169_private 
*tp)
 
        RTL_W8(tp, Config3, RTL_R8(tp, Config3) & ~Beacon_en);
 
-       if (tp->dev->mtu <= ETH_DATA_LEN)
-               rtl_tx_performance_tweak(tp, PCI_EXP_DEVCTL_READRQ_4096B);
-
        rtl_disable_clock_request(tp);
 }
 
@@ -4490,9 +4490,6 @@ static void rtl_hw_start_8168cp_2(struct rtl8169_private 
*tp)
        rtl_set_def_aspm_entry_latency(tp);
 
        RTL_W8(tp, Config3, RTL_R8(tp, Config3) & ~Beacon_en);
-
-       if (tp->dev->mtu <= ETH_DATA_LEN)
-               rtl_tx_performance_tweak(tp, PCI_EXP_DEVCTL_READRQ_4096B);
 }
 
 static void rtl_hw_start_8168cp_3(struct rtl8169_private *tp)
@@ -4503,9 +4500,6 @@ static void rtl_hw_start_8168cp_3(struct rtl8169_private 
*tp)
 
        /* Magic. */
        RTL_W8(tp, DBG_REG, 0x20);
-
-       if (tp->dev->mtu <= ETH_DATA_LEN)
-               rtl_tx_performance_tweak(tp, PCI_EXP_DEVCTL_READRQ_4096B);
 }
 
 static void rtl_hw_start_8168c_1(struct rtl8169_private *tp)
@@ -4611,9 +4605,6 @@ static void rtl_hw_start_8168e_1(struct rtl8169_private 
*tp)
 
        rtl_ephy_init(tp, e_info_8168e_1);
 
-       if (tp->dev->mtu <= ETH_DATA_LEN)
-               rtl_tx_performance_tweak(tp, PCI_EXP_DEVCTL_READRQ_4096B);
-
        rtl_disable_clock_request(tp);
 
        /* Reset tx FIFO pointer */
@@ -4636,9 +4627,6 @@ static void rtl_hw_start_8168e_2(struct rtl8169_private 
*tp)
 
        rtl_ephy_init(tp, e_info_8168e_2);
 
-       if (tp->dev->mtu <= ETH_DATA_LEN)
-               rtl_tx_performance_tweak(tp, PCI_EXP_DEVCTL_READRQ_4096B);
-
        rtl_eri_write(tp, 0xc0, ERIAR_MASK_0011, 0x0000);
        rtl_eri_write(tp, 0xb8, ERIAR_MASK_0011, 0x0000);
        rtl_set_fifo_size(tp, 0x10, 0x10, 0x02, 0x06);
@@ -5485,6 +5473,8 @@ static void rtl_hw_start(struct  rtl8169_private *tp)
        rtl_set_rx_tx_desc_registers(tp);
        rtl_lock_config_regs(tp);
 
+       rtl_jumbo_config(tp, tp->dev->mtu);
+
        /* Initially a 10 us delay. Turned it into a PCI commit. - FR */
        RTL_R16(tp, CPlusCmd);
        RTL_W8(tp, ChipCmd, CmdTxEnb | CmdRxEnb);
@@ -5498,10 +5488,7 @@ static int rtl8169_change_mtu(struct net_device *dev, 
int new_mtu)
 {
        struct rtl8169_private *tp = netdev_priv(dev);
 
-       if (new_mtu > ETH_DATA_LEN)
-               rtl_hw_jumbo_enable(tp);
-       else
-               rtl_hw_jumbo_disable(tp);
+       rtl_jumbo_config(tp, new_mtu);
 
        dev->mtu = new_mtu;
        netdev_update_features(dev);
-- 
2.23.0