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[PATCH net-next v2 2/2] r8169: enable LTR support

javen posted 2 patches 1 month ago
There is a newer version of this series
[PATCH net-next v2 2/2] r8169: enable LTR support
Posted by javen 1 month ago 
From: Javen Xu <javen_xu@realsil.com.cn>

This patch will enable
RTL8168FP/RTL8168EP/RTL8168H/RTL8125/RTL8126/RTL8127 LTR support.

Signed-off-by: Javen Xu <javen_xu@realsil.com.cn>

---
v2: Replace some register numbers with names according to datasheet.
---
 drivers/net/ethernet/realtek/r8169_main.c | 112 ++++++++++++++++++++++
 1 file changed, 112 insertions(+)

diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
index f9df6aadacce..1ee5a0b5a6a0 100644
--- a/drivers/net/ethernet/realtek/r8169_main.c
+++ b/drivers/net/ethernet/realtek/r8169_main.c
@@ -312,6 +312,15 @@ enum rtl_registers {
 	IBIMR0          = 0xfa,
 	IBISR0          = 0xfb,
 	FuncForceEvent	= 0xfc,
+
+	ALDPS_LTR	= 0xe0a2,
+	LTR_OBFF_LOCK	= 0xe032,
+	LTR_SNOOP	= 0xe034,
+
+#define ALDPS_LTR_EN			BIT(0)
+#define LTR_OBFF_LOCK_EN		BIT(0)
+#define LINK_SPEED_CHANGE_EN		BIT(14)
+#define LTR_SNOOP_EN			GENMASK(15, 14)
 };
 
 enum rtl8168_8101_registers {
@@ -397,6 +406,8 @@ enum rtl8168_registers {
 #define PWM_EN				(1 << 22)
 #define RXDV_GATED_EN			(1 << 19)
 #define EARLY_TALLY_EN			(1 << 16)
+	COMBO_LTR_EXTEND = 0xb6,
+#define COMBO_LTR_EXTEND_EN 	BIT(0)
 };
 
 enum rtl8125_registers {
@@ -2919,6 +2930,104 @@ static void rtl_disable_exit_l1(struct rtl8169_private *tp)
 	}
 }
 
+static void rtl_enable_ltr(struct rtl8169_private *tp)
+{
+	switch (tp->mac_version) {
+	case RTL_GIGA_MAC_VER_80:
+		r8168_mac_ocp_write(tp, 0xcdd0, 0x9003);
+		r8168_mac_ocp_modify(tp, LTR_SNOOP, 0x0000, LTR_SNOOP_EN);
+		r8168_mac_ocp_modify(tp, ALDPS_LTR, 0x0000, ALDPS_LTR_EN);
+		r8168_mac_ocp_write(tp, 0xcdd2, 0x8c09);
+		r8168_mac_ocp_write(tp, 0xcdd8, 0x9003);
+		r8168_mac_ocp_write(tp, 0xcdd4, 0x9003);
+		r8168_mac_ocp_write(tp, 0xcdda, 0x9003);
+		r8168_mac_ocp_write(tp, 0xcdd6, 0x9003);
+		r8168_mac_ocp_write(tp, 0xcddc, 0x9003);
+		r8168_mac_ocp_write(tp, 0xcde8, 0x887a);
+		r8168_mac_ocp_write(tp, 0xcdea, 0x9003);
+		r8168_mac_ocp_write(tp, 0xcdec, 0x8c09);
+		r8168_mac_ocp_write(tp, 0xcdee, 0x9003);
+		r8168_mac_ocp_write(tp, 0xcdf0, 0x8a62);
+		r8168_mac_ocp_write(tp, 0xcdf2, 0x9003);
+		r8168_mac_ocp_write(tp, 0xcdf4, 0x883e);
+		r8168_mac_ocp_write(tp, 0xcdf6, 0x9003);
+		r8168_mac_ocp_write(tp, 0xcdf8, 0x8849);
+		r8168_mac_ocp_write(tp, 0xcdfa, 0x9003);
+		r8168_mac_ocp_modify(tp, LTR_OBFF_LOCK, 0x0000, LINK_SPEED_CHANGE_EN);
+		break;
+	case RTL_GIGA_MAC_VER_70:
+		r8168_mac_ocp_write(tp, 0xcdd0, 0x9003);
+		r8168_mac_ocp_modify(tp, LTR_SNOOP, 0x0000, LTR_SNOOP_EN);
+		r8168_mac_ocp_modify(tp, ALDPS_LTR, 0x0000, ALDPS_LTR_EN);
+		r8168_mac_ocp_write(tp, 0xcdd2, 0x8c09);
+		r8168_mac_ocp_write(tp, 0xcdd8, 0x9003);
+		r8168_mac_ocp_write(tp, 0xcdd4, 0x9003);
+		r8168_mac_ocp_write(tp, 0xcdda, 0x9003);
+		r8168_mac_ocp_write(tp, 0xcdd6, 0x9003);
+		r8168_mac_ocp_write(tp, 0xcddc, 0x9003);
+		r8168_mac_ocp_write(tp, 0xcde8, 0x887a);
+		r8168_mac_ocp_write(tp, 0xcdea, 0x9003);
+		r8168_mac_ocp_write(tp, 0xcdec, 0x8c09);
+		r8168_mac_ocp_write(tp, 0xcdee, 0x9003);
+		r8168_mac_ocp_write(tp, 0xcdf0, 0x8a62);
+		r8168_mac_ocp_write(tp, 0xcdf2, 0x9003);
+		r8168_mac_ocp_write(tp, 0xcdf4, 0x883e);
+		r8168_mac_ocp_write(tp, 0xcdf6, 0x9003);
+		r8168_mac_ocp_modify(tp, LTR_OBFF_LOCK, 0x0000, LINK_SPEED_CHANGE_EN);
+		break;
+	case RTL_GIGA_MAC_VER_61 ... RTL_GIGA_MAC_VER_66:
+		r8168_mac_ocp_write(tp, 0xcdd0, 0x9003);
+		r8168_mac_ocp_modify(tp, LTR_SNOOP, 0x0000, LTR_SNOOP_EN);
+		r8168_mac_ocp_modify(tp, ALDPS_LTR, 0x0000, ALDPS_LTR_EN);
+		r8168_mac_ocp_write(tp, 0xcdd2, 0x889c);
+		r8168_mac_ocp_write(tp, 0xcdd8, 0x9003);
+		r8168_mac_ocp_write(tp, 0xcdd4, 0x8c30);
+		r8168_mac_ocp_write(tp, 0xcdda, 0x9003);
+		r8168_mac_ocp_write(tp, 0xcdd6, 0x9003);
+		r8168_mac_ocp_write(tp, 0xcddc, 0x9003);
+		r8168_mac_ocp_write(tp, 0xcde8, 0x883e);
+		r8168_mac_ocp_write(tp, 0xcdea, 0x9003);
+		r8168_mac_ocp_write(tp, 0xcdec, 0x889c);
+		r8168_mac_ocp_write(tp, 0xcdee, 0x9003);
+		r8168_mac_ocp_write(tp, 0xcdf0, 0x8C09);
+		r8168_mac_ocp_write(tp, 0xcdf2, 0x9003);
+		r8168_mac_ocp_modify(tp, LTR_OBFF_LOCK, 0x0000, LINK_SPEED_CHANGE_EN);
+		break;
+	case RTL_GIGA_MAC_VER_46 ... RTL_GIGA_MAC_VER_48:
+	case RTL_GIGA_MAC_VER_52:
+		r8168_mac_ocp_modify(tp, ALDPS_LTR, 0x0000, ALDPS_LTR_EN);
+		RTL_W8(tp, COMBO_LTR_EXTEND, RTL_R8(tp, COMBO_LTR_EXTEND) | COMBO_LTR_EXTEND_EN);
+		fallthrough;
+	case RTL_GIGA_MAC_VER_51:
+		r8168_mac_ocp_modify(tp, LTR_SNOOP, 0x0000, LTR_SNOOP_EN);
+		r8168_mac_ocp_write(tp, 0xe02c, 0x1880);
+		r8168_mac_ocp_write(tp, 0xe02e, 0x4880);
+		r8168_mac_ocp_write(tp, 0xcdd8, 0x9003);
+		r8168_mac_ocp_write(tp, 0xcdda, 0x9003);
+		r8168_mac_ocp_write(tp, 0xcddc, 0x9003);
+		r8168_mac_ocp_write(tp, 0xcdd2, 0x883c);
+		r8168_mac_ocp_write(tp, 0xcdd4, 0x8c12);
+		r8168_mac_ocp_write(tp, 0xcdd6, 0x9003);
+		break;
+	default:
+		return;
+	}
+	/* chip can trigger LTR */
+	r8168_mac_ocp_modify(tp, LTR_OBFF_LOCK, 0x0003, LTR_OBFF_LOCK_EN);
+}
+
+static void rtl_disable_ltr(struct rtl8169_private *tp)
+{
+	switch (tp->mac_version) {
+	case RTL_GIGA_MAC_VER_46 ... RTL_GIGA_MAC_VER_80:
+		r8168_mac_ocp_modify(tp, 0xe032, 0x0003, 0);
+		break;
+	default:
+		break;
+	}
+}
+
+
 static void rtl_hw_aspm_clkreq_enable(struct rtl8169_private *tp, bool enable)
 {
 	u8 val8;
@@ -2947,6 +3056,7 @@ static void rtl_hw_aspm_clkreq_enable(struct rtl8169_private *tp, bool enable)
 			break;
 		}
 
+		rtl_enable_ltr(tp);
 		switch (tp->mac_version) {
 		case RTL_GIGA_MAC_VER_46 ... RTL_GIGA_MAC_VER_48:
 		case RTL_GIGA_MAC_VER_61 ... RTL_GIGA_MAC_VER_LAST:
@@ -2968,6 +3078,7 @@ static void rtl_hw_aspm_clkreq_enable(struct rtl8169_private *tp, bool enable)
 			break;
 		}
 
+		rtl_disable_ltr(tp);
 		switch (tp->mac_version) {
 		case RTL_GIGA_MAC_VER_70:
 		case RTL_GIGA_MAC_VER_80:
@@ -4811,6 +4922,7 @@ static void rtl8169_down(struct rtl8169_private *tp)
 
 	rtl8169_cleanup(tp);
 	rtl_disable_exit_l1(tp);
+	rtl_disable_ltr(tp);
 	rtl_prepare_power_down(tp);
 
 	if (tp->dash_type != RTL_DASH_NONE && !tp->saved_wolopts)
-- 
2.43.0
Re: [PATCH net-next v2 2/2] r8169: enable LTR support
Posted by Heiner Kallweit 1 month ago 
On 1/8/2026 3:35 AM, javen wrote:
> From: Javen Xu <javen_xu@realsil.com.cn>
> 
> This patch will enable
> RTL8168FP/RTL8168EP/RTL8168H/RTL8125/RTL8126/RTL8127 LTR support.
> 
> Signed-off-by: Javen Xu <javen_xu@realsil.com.cn>
> 
> ---
> v2: Replace some register numbers with names according to datasheet.
> ---
>  drivers/net/ethernet/realtek/r8169_main.c | 112 ++++++++++++++++++++++
>  1 file changed, 112 insertions(+)
> 
> diff --git a/drivers/net/ethernet/realtek/r8169_main.c b/drivers/net/ethernet/realtek/r8169_main.c
> index f9df6aadacce..1ee5a0b5a6a0 100644
> --- a/drivers/net/ethernet/realtek/r8169_main.c
> +++ b/drivers/net/ethernet/realtek/r8169_main.c
> @@ -312,6 +312,15 @@ enum rtl_registers {
>  	IBIMR0          = 0xfa,
>  	IBISR0          = 0xfb,
>  	FuncForceEvent	= 0xfc,
> +
> +	ALDPS_LTR	= 0xe0a2,
> +	LTR_OBFF_LOCK	= 0xe032,
> +	LTR_SNOOP	= 0xe034,
> +
> +#define ALDPS_LTR_EN			BIT(0)
> +#define LTR_OBFF_LOCK_EN		BIT(0)
> +#define LINK_SPEED_CHANGE_EN		BIT(14)
> +#define LTR_SNOOP_EN			GENMASK(15, 14)
>  };
>  
>  enum rtl8168_8101_registers {
> @@ -397,6 +406,8 @@ enum rtl8168_registers {
>  #define PWM_EN				(1 << 22)
>  #define RXDV_GATED_EN			(1 << 19)
>  #define EARLY_TALLY_EN			(1 << 16)
> +	COMBO_LTR_EXTEND = 0xb6,
> +#define COMBO_LTR_EXTEND_EN 	BIT(0)
>  };
>  
>  enum rtl8125_registers {
> @@ -2919,6 +2930,104 @@ static void rtl_disable_exit_l1(struct rtl8169_private *tp)
>  	}
>  }
>  
> +static void rtl_enable_ltr(struct rtl8169_private *tp)
> +{
> +	switch (tp->mac_version) {
> +	case RTL_GIGA_MAC_VER_80:
> +		r8168_mac_ocp_write(tp, 0xcdd0, 0x9003);
> +		r8168_mac_ocp_modify(tp, LTR_SNOOP, 0x0000, LTR_SNOOP_EN);
> +		r8168_mac_ocp_modify(tp, ALDPS_LTR, 0x0000, ALDPS_LTR_EN);
> +		r8168_mac_ocp_write(tp, 0xcdd2, 0x8c09);
> +		r8168_mac_ocp_write(tp, 0xcdd8, 0x9003);
> +		r8168_mac_ocp_write(tp, 0xcdd4, 0x9003);
> +		r8168_mac_ocp_write(tp, 0xcdda, 0x9003);
> +		r8168_mac_ocp_write(tp, 0xcdd6, 0x9003);
> +		r8168_mac_ocp_write(tp, 0xcddc, 0x9003);
> +		r8168_mac_ocp_write(tp, 0xcde8, 0x887a);
> +		r8168_mac_ocp_write(tp, 0xcdea, 0x9003);
> +		r8168_mac_ocp_write(tp, 0xcdec, 0x8c09);
> +		r8168_mac_ocp_write(tp, 0xcdee, 0x9003);
> +		r8168_mac_ocp_write(tp, 0xcdf0, 0x8a62);
> +		r8168_mac_ocp_write(tp, 0xcdf2, 0x9003);
> +		r8168_mac_ocp_write(tp, 0xcdf4, 0x883e);
> +		r8168_mac_ocp_write(tp, 0xcdf6, 0x9003);
> +		r8168_mac_ocp_write(tp, 0xcdf8, 0x8849);
> +		r8168_mac_ocp_write(tp, 0xcdfa, 0x9003);
> +		r8168_mac_ocp_modify(tp, LTR_OBFF_LOCK, 0x0000, LINK_SPEED_CHANGE_EN);
> +		break;
> +	case RTL_GIGA_MAC_VER_70:
> +		r8168_mac_ocp_write(tp, 0xcdd0, 0x9003);
> +		r8168_mac_ocp_modify(tp, LTR_SNOOP, 0x0000, LTR_SNOOP_EN);
> +		r8168_mac_ocp_modify(tp, ALDPS_LTR, 0x0000, ALDPS_LTR_EN);
> +		r8168_mac_ocp_write(tp, 0xcdd2, 0x8c09);
> +		r8168_mac_ocp_write(tp, 0xcdd8, 0x9003);
> +		r8168_mac_ocp_write(tp, 0xcdd4, 0x9003);
> +		r8168_mac_ocp_write(tp, 0xcdda, 0x9003);
> +		r8168_mac_ocp_write(tp, 0xcdd6, 0x9003);
> +		r8168_mac_ocp_write(tp, 0xcddc, 0x9003);
> +		r8168_mac_ocp_write(tp, 0xcde8, 0x887a);
> +		r8168_mac_ocp_write(tp, 0xcdea, 0x9003);
> +		r8168_mac_ocp_write(tp, 0xcdec, 0x8c09);
> +		r8168_mac_ocp_write(tp, 0xcdee, 0x9003);
> +		r8168_mac_ocp_write(tp, 0xcdf0, 0x8a62);
> +		r8168_mac_ocp_write(tp, 0xcdf2, 0x9003);
> +		r8168_mac_ocp_write(tp, 0xcdf4, 0x883e);
> +		r8168_mac_ocp_write(tp, 0xcdf6, 0x9003);
> +		r8168_mac_ocp_modify(tp, LTR_OBFF_LOCK, 0x0000, LINK_SPEED_CHANGE_EN);
> +		break;
> +	case RTL_GIGA_MAC_VER_61 ... RTL_GIGA_MAC_VER_66:
> +		r8168_mac_ocp_write(tp, 0xcdd0, 0x9003);
> +		r8168_mac_ocp_modify(tp, LTR_SNOOP, 0x0000, LTR_SNOOP_EN);
> +		r8168_mac_ocp_modify(tp, ALDPS_LTR, 0x0000, ALDPS_LTR_EN);
> +		r8168_mac_ocp_write(tp, 0xcdd2, 0x889c);
> +		r8168_mac_ocp_write(tp, 0xcdd8, 0x9003);
> +		r8168_mac_ocp_write(tp, 0xcdd4, 0x8c30);
> +		r8168_mac_ocp_write(tp, 0xcdda, 0x9003);
> +		r8168_mac_ocp_write(tp, 0xcdd6, 0x9003);
> +		r8168_mac_ocp_write(tp, 0xcddc, 0x9003);
> +		r8168_mac_ocp_write(tp, 0xcde8, 0x883e);
> +		r8168_mac_ocp_write(tp, 0xcdea, 0x9003);
> +		r8168_mac_ocp_write(tp, 0xcdec, 0x889c);
> +		r8168_mac_ocp_write(tp, 0xcdee, 0x9003);
> +		r8168_mac_ocp_write(tp, 0xcdf0, 0x8C09);
> +		r8168_mac_ocp_write(tp, 0xcdf2, 0x9003);
> +		r8168_mac_ocp_modify(tp, LTR_OBFF_LOCK, 0x0000, LINK_SPEED_CHANGE_EN);
> +		break;
> +	case RTL_GIGA_MAC_VER_46 ... RTL_GIGA_MAC_VER_48:
> +	case RTL_GIGA_MAC_VER_52:
> +		r8168_mac_ocp_modify(tp, ALDPS_LTR, 0x0000, ALDPS_LTR_EN);
> +		RTL_W8(tp, COMBO_LTR_EXTEND, RTL_R8(tp, COMBO_LTR_EXTEND) | COMBO_LTR_EXTEND_EN);
> +		fallthrough;
> +	case RTL_GIGA_MAC_VER_51:
> +		r8168_mac_ocp_modify(tp, LTR_SNOOP, 0x0000, LTR_SNOOP_EN);
> +		r8168_mac_ocp_write(tp, 0xe02c, 0x1880);
> +		r8168_mac_ocp_write(tp, 0xe02e, 0x4880);
> +		r8168_mac_ocp_write(tp, 0xcdd8, 0x9003);
> +		r8168_mac_ocp_write(tp, 0xcdda, 0x9003);
> +		r8168_mac_ocp_write(tp, 0xcddc, 0x9003);
> +		r8168_mac_ocp_write(tp, 0xcdd2, 0x883c);
> +		r8168_mac_ocp_write(tp, 0xcdd4, 0x8c12);
> +		r8168_mac_ocp_write(tp, 0xcdd6, 0x9003);
> +		break;
> +	default:
> +		return;
> +	}
> +	/* chip can trigger LTR */
> +	r8168_mac_ocp_modify(tp, LTR_OBFF_LOCK, 0x0003, LTR_OBFF_LOCK_EN);
> +}
> +
> +static void rtl_disable_ltr(struct rtl8169_private *tp)
> +{

You wrote in response to my question on v1: "We generally do not recommend disabling LTR."
Then, can't this function be removed? Or what would be the impact of leaving LTR enabled?

Please also address the checkpatch warnings, as reported by CI:
https://patchwork.kernel.org/project/netdevbpf/patch/20260108023523.1019-3-javen_xu@realsil.com.cn/


> +	switch (tp->mac_version) {
> +	case RTL_GIGA_MAC_VER_46 ... RTL_GIGA_MAC_VER_80:
> +		r8168_mac_ocp_modify(tp, 0xe032, 0x0003, 0);
> +		break;
> +	default:
> +		break;
> +	}
> +}
> +
> +
>  static void rtl_hw_aspm_clkreq_enable(struct rtl8169_private *tp, bool enable)
>  {
>  	u8 val8;
> @@ -2947,6 +3056,7 @@ static void rtl_hw_aspm_clkreq_enable(struct rtl8169_private *tp, bool enable)
>  			break;
>  		}
>  
> +		rtl_enable_ltr(tp);
>  		switch (tp->mac_version) {
>  		case RTL_GIGA_MAC_VER_46 ... RTL_GIGA_MAC_VER_48:
>  		case RTL_GIGA_MAC_VER_61 ... RTL_GIGA_MAC_VER_LAST:
> @@ -2968,6 +3078,7 @@ static void rtl_hw_aspm_clkreq_enable(struct rtl8169_private *tp, bool enable)
>  			break;
>  		}
>  
> +		rtl_disable_ltr(tp);
>  		switch (tp->mac_version) {
>  		case RTL_GIGA_MAC_VER_70:
>  		case RTL_GIGA_MAC_VER_80:
> @@ -4811,6 +4922,7 @@ static void rtl8169_down(struct rtl8169_private *tp)
>  
>  	rtl8169_cleanup(tp);
>  	rtl_disable_exit_l1(tp);
> +	rtl_disable_ltr(tp);
>  	rtl_prepare_power_down(tp);
>  
>  	if (tp->dash_type != RTL_DASH_NONE && !tp->saved_wolopts)

Patchew 2.1-devel-b67e4c2

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