[PATCH net] r8169: fix network stalls due to missing bit TXCFG_AUTO_FIFO

[PATCH net] r8169: fix network stalls due to missing bit TXCFG_AUTO_FIFO

[Heiner Kallweit]

Some of the chip-specific hw_start functions set bit TXCFG_AUTO_FIFO
in register TxConfig. The original patch changed the order of some
calls resulting in these changes being overwritten by
rtl_set_tx_config_registers() in rtl_hw_start(). This eventually
resulted in network stalls especially under high load.

Analyzing the chip-specific hw_start functions all chip version from
34, with the exception of version 39, need this bit set.
This patch moves setting this bit to rtl_set_tx_config_registers().

Fixes: 4fd48c4ac0a0 ("r8169: move common initializations to tp->hw_start")
Reported-by: Ortwin Glück <odi@odi.ch>
Reported-by: David Arendt <admin@prnet.org>
Tested-by: Tony Atkinson <tatkinson@linux.com>
Tested-by: David Arendt <admin@prnet.org>
Tested-by: Ortwin Glück <odi@odi.ch>
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
---
Hint for applying this change to stable:
It may collide with 05212ba8132b ("r8169: set RxConfig after tx/rx is
enabled for RTL8169sb/8110sb devices") which renamed
rtl_set_rx_tx_config_registers() to rtl_set_tx_config_registers().
---
 drivers/net/ethernet/realtek/r8169.c | 20 ++++++++------------
 1 file changed, 8 insertions(+), 12 deletions(-)

diff --git a/drivers/net/ethernet/realtek/r8169.c b/drivers/net/ethernet/realtek/r8169.c
index f882be49f..ae8abe900 100644
--- a/drivers/net/ethernet/realtek/r8169.c
+++ b/drivers/net/ethernet/realtek/r8169.c
@@ -4514,9 +4514,14 @@ static void rtl8169_hw_reset(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) |
-		(InterFrameGap << TxInterFrameGapShift));
+	u32 val = TX_DMA_BURST << TxDMAShift |
+		  InterFrameGap << TxInterFrameGapShift;
+
+	if (tp->mac_version >= RTL_GIGA_MAC_VER_34 &&
+	    tp->mac_version != RTL_GIGA_MAC_VER_39)
+		val |= TXCFG_AUTO_FIFO;
+
+	RTL_W32(tp, TxConfig, val);
 }
 
 static void rtl_set_rx_max_size(struct rtl8169_private *tp)
@@ -5011,7 +5016,6 @@ static void rtl_hw_start_8168e_2(struct rtl8169_private *tp)
 
 	rtl_disable_clock_request(tp);
 
-	RTL_W32(tp, TxConfig, RTL_R32(tp, TxConfig) | TXCFG_AUTO_FIFO);
 	RTL_W8(tp, MCU, RTL_R8(tp, MCU) & ~NOW_IS_OOB);
 
 	/* Adjust EEE LED frequency */
@@ -5045,7 +5049,6 @@ static void rtl_hw_start_8168f(struct rtl8169_private *tp)
 
 	rtl_disable_clock_request(tp);
 
-	RTL_W32(tp, TxConfig, RTL_R32(tp, TxConfig) | TXCFG_AUTO_FIFO);
 	RTL_W8(tp, MCU, RTL_R8(tp, MCU) & ~NOW_IS_OOB);
 	RTL_W8(tp, DLLPR, RTL_R8(tp, DLLPR) | PFM_EN);
 	RTL_W32(tp, MISC, RTL_R32(tp, MISC) | PWM_EN);
@@ -5090,8 +5093,6 @@ static void rtl_hw_start_8411(struct rtl8169_private *tp)
 
 static void rtl_hw_start_8168g(struct rtl8169_private *tp)
 {
-	RTL_W32(tp, TxConfig, RTL_R32(tp, TxConfig) | TXCFG_AUTO_FIFO);
-
 	rtl_eri_write(tp, 0xc8, ERIAR_MASK_0101, 0x080002, ERIAR_EXGMAC);
 	rtl_eri_write(tp, 0xcc, ERIAR_MASK_0001, 0x38, ERIAR_EXGMAC);
 	rtl_eri_write(tp, 0xd0, ERIAR_MASK_0001, 0x48, ERIAR_EXGMAC);
@@ -5189,8 +5190,6 @@ static void rtl_hw_start_8168h_1(struct rtl8169_private *tp)
 	rtl_hw_aspm_clkreq_enable(tp, false);
 	rtl_ephy_init(tp, e_info_8168h_1, ARRAY_SIZE(e_info_8168h_1));
 
-	RTL_W32(tp, TxConfig, RTL_R32(tp, TxConfig) | TXCFG_AUTO_FIFO);
-
 	rtl_eri_write(tp, 0xc8, ERIAR_MASK_0101, 0x00080002, ERIAR_EXGMAC);
 	rtl_eri_write(tp, 0xcc, ERIAR_MASK_0001, 0x38, ERIAR_EXGMAC);
 	rtl_eri_write(tp, 0xd0, ERIAR_MASK_0001, 0x48, ERIAR_EXGMAC);
@@ -5273,8 +5272,6 @@ static void rtl_hw_start_8168ep(struct rtl8169_private *tp)
 {
 	rtl8168ep_stop_cmac(tp);
 
-	RTL_W32(tp, TxConfig, RTL_R32(tp, TxConfig) | TXCFG_AUTO_FIFO);
-
 	rtl_eri_write(tp, 0xc8, ERIAR_MASK_0101, 0x00080002, ERIAR_EXGMAC);
 	rtl_eri_write(tp, 0xcc, ERIAR_MASK_0001, 0x2f, ERIAR_EXGMAC);
 	rtl_eri_write(tp, 0xd0, ERIAR_MASK_0001, 0x5f, ERIAR_EXGMAC);
@@ -5596,7 +5593,6 @@ static void rtl_hw_start_8402(struct rtl8169_private *tp)
 	/* Force LAN exit from ASPM if Rx/Tx are not idle */
 	RTL_W32(tp, FuncEvent, RTL_R32(tp, FuncEvent) | 0x002800);
 
-	RTL_W32(tp, TxConfig, RTL_R32(tp, TxConfig) | TXCFG_AUTO_FIFO);
 	RTL_W8(tp, MCU, RTL_R8(tp, MCU) & ~NOW_IS_OOB);
 
 	rtl_ephy_init(tp, e_info_8402, ARRAY_SIZE(e_info_8402));
-- 
2.19.0

Re: [net] r8169: fix network stalls due to missing bit TXCFG_AUTO_FIFO

[Maciej S. Szmigiero]

On 28.09.2018 22:19, Heiner Kallweit wrote:
> Some of the chip-specific hw_start functions set bit TXCFG_AUTO_FIFO
> in register TxConfig. The original patch changed the order of some
> calls resulting in these changes being overwritten by
> rtl_set_tx_config_registers() in rtl_hw_start(). This eventually
> resulted in network stalls especially under high load.
> 
> Analyzing the chip-specific hw_start functions all chip version from
> 34, with the exception of version 39, need this bit set.
> This patch moves setting this bit to rtl_set_tx_config_registers().
> 
> Fixes: 4fd48c4ac0a0 ("r8169: move common initializations to tp->hw_start")
> Reported-by: Ortwin Glück <odi@odi.ch>
> Reported-by: David Arendt <admin@prnet.org>
> Tested-by: Tony Atkinson <tatkinson@linux.com>
> Tested-by: David Arendt <admin@prnet.org>
> Tested-by: Ortwin Glück <odi@odi.ch>
> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>

Please add:
Root-caused-by: Maciej S. Szmigiero <mail@maciej.szmigiero.name>

Thanks,
Maciej

Re: [net] r8169: fix network stalls due to missing bit TXCFG_AUTO_FIFO

[Heiner Kallweit]

On 28.09.2018 23:47, Maciej S. Szmigiero wrote:
> On 28.09.2018 22:19, Heiner Kallweit wrote:
>> Some of the chip-specific hw_start functions set bit TXCFG_AUTO_FIFO
>> in register TxConfig. The original patch changed the order of some
>> calls resulting in these changes being overwritten by
>> rtl_set_tx_config_registers() in rtl_hw_start(). This eventually
>> resulted in network stalls especially under high load.
>>
>> Analyzing the chip-specific hw_start functions all chip version from
>> 34, with the exception of version 39, need this bit set.
>> This patch moves setting this bit to rtl_set_tx_config_registers().
>>
>> Fixes: 4fd48c4ac0a0 ("r8169: move common initializations to tp->hw_start")
>> Reported-by: Ortwin Glück <odi@odi.ch>
>> Reported-by: David Arendt <admin@prnet.org>
>> Tested-by: Tony Atkinson <tatkinson@linux.com>
>> Tested-by: David Arendt <admin@prnet.org>
>> Tested-by: Ortwin Glück <odi@odi.ch>
>> Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
> 
> Please add:
> Root-caused-by: Maciej S. Szmigiero <mail@maciej.szmigiero.name>
> 
Sure, forgot you in the list.

Heiner

> Thanks,
> Maciej
>