[PATCH net-next v2] r8169: set EEE speed down ratio to 1

[PATCH net-next v2] r8169: set EEE speed down ratio to 1

[ChunHao Lin]

EEE speed down means speed down MAC MCU clock. It is not from spec.
It is kind of Realtek specific power saving feature. But enable it
may cause some issues, like packet drop or interrupt loss. Different
hardware may have different issues.

EEE speed down ratio (mac ocp 0xe056[7:4]) is used to set EEE speed
down rate. The larger this value is, the more power can save. But it
actually save less power then we expected. And, as mentioned above,
will impact compatibility. So set it to 1 (mac ocp 0xe056[7:4] = 0)
, which means not to speed down, to improve compatibility.

Signed-off-by: ChunHao Lin <hau@realtek.com>
---
v1 -> v2: update commit message

 drivers/net/ethernet/realtek/r8169_main.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
index 75272510f7e2..8903ae90afcb 100644
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -3409,7 +3409,7 @@ static void rtl_hw_start_8168h_1(struct rtl8169_private *tp)
 		r8168_mac_ocp_modify(tp, 0xd412, 0x0fff, sw_cnt_1ms_ini);
 	}
 
-	r8168_mac_ocp_modify(tp, 0xe056, 0x00f0, 0x0070);
+	r8168_mac_ocp_modify(tp, 0xe056, 0x00f0, 0x0000);
 	r8168_mac_ocp_modify(tp, 0xe052, 0x6000, 0x8008);
 	r8168_mac_ocp_modify(tp, 0xe0d6, 0x01ff, 0x017f);
 	r8168_mac_ocp_modify(tp, 0xd420, 0x0fff, 0x047f);
@@ -3514,7 +3514,7 @@ static void rtl_hw_start_8117(struct rtl8169_private *tp)
 		r8168_mac_ocp_modify(tp, 0xd412, 0x0fff, sw_cnt_1ms_ini);
 	}
 
-	r8168_mac_ocp_modify(tp, 0xe056, 0x00f0, 0x0070);
+	r8168_mac_ocp_modify(tp, 0xe056, 0x00f0, 0x0000);
 	r8168_mac_ocp_write(tp, 0xea80, 0x0003);
 	r8168_mac_ocp_modify(tp, 0xe052, 0x0000, 0x0009);
 	r8168_mac_ocp_modify(tp, 0xd420, 0x0fff, 0x047f);
@@ -3715,7 +3715,7 @@ static void rtl_hw_start_8125_common(struct rtl8169_private *tp)
 	r8168_mac_ocp_modify(tp, 0xc0b4, 0x0000, 0x000c);
 	r8168_mac_ocp_modify(tp, 0xeb6a, 0x00ff, 0x0033);
 	r8168_mac_ocp_modify(tp, 0xeb50, 0x03e0, 0x0040);
-	r8168_mac_ocp_modify(tp, 0xe056, 0x00f0, 0x0030);
+	r8168_mac_ocp_modify(tp, 0xe056, 0x00f0, 0x0000);
 	r8168_mac_ocp_modify(tp, 0xe040, 0x1000, 0x0000);
 	r8168_mac_ocp_modify(tp, 0xea1c, 0x0003, 0x0001);
 	if (tp->mac_version == RTL_GIGA_MAC_VER_70 ||
-- 
2.43.0

Re: [PATCH net-next v2] r8169: set EEE speed down ratio to 1

[Heiner Kallweit]

On 9/18/2025 4:34 AM, ChunHao Lin wrote:
> EEE speed down means speed down MAC MCU clock. It is not from spec.
> It is kind of Realtek specific power saving feature. But enable it
> may cause some issues, like packet drop or interrupt loss. Different
> hardware may have different issues.
> 
> EEE speed down ratio (mac ocp 0xe056[7:4]) is used to set EEE speed
> down rate. The larger this value is, the more power can save. But it
> actually save less power then we expected. And, as mentioned above,
> will impact compatibility. So set it to 1 (mac ocp 0xe056[7:4] = 0)
> , which means not to speed down, to improve compatibility.
> 
> Signed-off-by: ChunHao Lin <hau@realtek.com>
> ---
> v1 -> v2: update commit message
> 
Reviewed-by: Heiner Kallweit <hkallweit1@gmail.com>

Re: [PATCH net-next v2] r8169: set EEE speed down ratio to 1

[patchwork-bot+netdevbpf]

Hello:

This patch was applied to netdev/net-next.git (main)
by Jakub Kicinski <kuba@kernel.org>:

On Thu, 18 Sep 2025 10:34:25 +0800 you wrote:
> EEE speed down means speed down MAC MCU clock. It is not from spec.
> It is kind of Realtek specific power saving feature. But enable it
> may cause some issues, like packet drop or interrupt loss. Different
> hardware may have different issues.
> 
> EEE speed down ratio (mac ocp 0xe056[7:4]) is used to set EEE speed
> down rate. The larger this value is, the more power can save. But it
> actually save less power then we expected. And, as mentioned above,
> will impact compatibility. So set it to 1 (mac ocp 0xe056[7:4] = 0)
> , which means not to speed down, to improve compatibility.
> 
> [...]

Here is the summary with links:
  - [net-next,v2] r8169: set EEE speed down ratio to 1
    https://git.kernel.org/netdev/net-next/c/bf7154ffb1c6

You are awesome, thank you!
-- 
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html