[PATCH 4.18 028/197] r8169: set RxConfig after tx/rx is enabled for RTL8169sb/8110sb devices

From: Greg Kroah-Hartman
Date: Thu Sep 13 2018 - 09:51:51 EST


4.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Azat Khuzhin <a3at.mail@xxxxxxxxx>

[ Upstream commit 05212ba8132b42047ab5d63d759c6f9c28e7eab5 ]

I have two Ethernet adapters:
r8169 0000:03:01.0 eth0: RTL8169sb/8110sb, 00:14:d1:14:2d:49, XID 10000000, IRQ 18
r8169 0000:01:00.0 eth0: RTL8168e/8111e, 64:66:b3:11:14:5d, XID 2c200000, IRQ 30
And after upgrading from linux 4.15 [1] to linux 4.18+ [2] RTL8169sb failed to
receive any packets. tcpdump shows a lot of checksum mismatch.

[1]: a0f79386a4968b4925da6db2d1daffd0605a4402
[2]: 0519359784328bfa92bf0931bf0cff3b58c16932 (4.19 merge window opened)

I started bisecting and the found that [3] breaks it. According to [4]:
"For 8110S, 8110SB, and 8110SC series, the initial value of RxConfig
needs to be set after the tx/rx is enabled."
So I moved rtl_init_rxcfg() after enabling tx/rs and now my adapter works
(RTL8168e works too).

[3]: 3559d81e76bfe3803e89f2e04cf6ef7ab4f3aace
[4]: e542a2269f232d61270ceddd42b73a4348dee2bb ("r8169: adjust the RxConfig
settings.")

Also drop "rx" from rtl_set_rx_tx_config_registers(), since it does nothing
with it already.

Fixes: 3559d81e76bfe3803e89f2e04cf6ef7ab4f3aace ("r8169: simplify
rtl_hw_start_8169")

Cc: Heiner Kallweit <hkallweit1@xxxxxxxxx>
Cc: David S. Miller <davem@xxxxxxxxxxxxx>
Cc: netdev@xxxxxxxxxxxxxxx
Cc: Realtek linux nic maintainers <nic_swsd@xxxxxxxxxxx>
Signed-off-by: Azat Khuzhin <a3at.mail@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/ethernet/realtek/r8169.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)

--- a/drivers/net/ethernet/realtek/r8169.c
+++ b/drivers/net/ethernet/realtek/r8169.c
@@ -5039,7 +5039,7 @@ static void rtl8169_hw_reset(struct rtl8
rtl_hw_reset(tp);
}

-static void rtl_set_rx_tx_config_registers(struct rtl8169_private *tp)
+static void rtl_set_tx_config_registers(struct rtl8169_private *tp)
{
/* Set DMA burst size and Interframe Gap Time */
RTL_W32(tp, TxConfig, (TX_DMA_BURST << TxDMAShift) |
@@ -5150,12 +5150,14 @@ static void rtl_hw_start(struct rtl8169

rtl_set_rx_max_size(tp);
rtl_set_rx_tx_desc_registers(tp);
- rtl_set_rx_tx_config_registers(tp);
+ rtl_set_tx_config_registers(tp);
RTL_W8(tp, Cfg9346, Cfg9346_Lock);

/* Initially a 10 us delay. Turned it into a PCI commit. - FR */
RTL_R8(tp, IntrMask);
RTL_W8(tp, ChipCmd, CmdTxEnb | CmdRxEnb);
+ rtl_init_rxcfg(tp);
+
rtl_set_rx_mode(tp->dev);
/* no early-rx interrupts */
RTL_W16(tp, MultiIntr, RTL_R16(tp, MultiIntr) & 0xf000);