Subject: Re: [PATCH net 1/1] r8169: honor jumbo settings when chipset is requested to start.

From: Tomi Orava <[email-masked]>
Date: Thu, 28 Feb 2013 23:21:48 +0200

On 02/28/2013 01:01 AM, Francois Romieu wrote:
> 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 <[email-masked]>
> Signed-off-by: Francois Romieu <[email-masked]>
> Cc: Hayes Wang <[email-masked]>
> ---
> 
>  Tomi, can you give this one a try ? It should be the "don't break non
>  jumbo setup and fix similar problem on different chipsets" patch that
>  my previous hack wasn't.

I'll try this one out tomorrow. However, it seems that I was able
to get the same hang even with the previous patch when I turned the
power on ... All the previous testing I've done were just normal
reboot's and the one liner fixed those cases 100%, but once
I turned the power completely off and then back on, the NIC hanged
in the same way as before with the jumbo frames enabled from boot.

In case it matters, this happened with 3.4.33 kernel, as the 3.7.x
still have some unresolved nouveau bugs with my HTPC box graphics card.

Tomi

> 
>  drivers/net/ethernet/realtek/r8169.c | 27 ++++++++++++++++++---------
>  1 file changed, 18 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/net/ethernet/realtek/r8169.c b/drivers/net/ethernet/realtek/r8169.c
> index 8900398..28fb50a 100644
> --- a/drivers/net/ethernet/realtek/r8169.c
> +++ b/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);
>