[net-next,PATCH v5 1/3] dt-bindings: net: realtek,rtl82xx: Keep property list sorted

[net-next,PATCH v5 1/3] dt-bindings: net: realtek,rtl82xx: Keep property list sorted

[Marek Vasut]

Sort the documented properties alphabetically, no functional change.

Acked-by: Rob Herring (Arm) <robh@kernel.org>
Signed-off-by: Marek Vasut <marek.vasut@mailbox.org>
---
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Aleksander Jan Bajkowski <olek2@wp.pl>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Conor Dooley <conor+dt@kernel.org>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Heiner Kallweit <hkallweit1@gmail.com>
Cc: Ivan Galkin <ivan.galkin@axis.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Krzysztof Kozlowski <krzk+dt@kernel.org>
Cc: Michael Klein <michael@fossekall.de>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Vladimir Oltean <vladimir.oltean@nxp.com>
Cc: devicetree@vger.kernel.org
Cc: netdev@vger.kernel.org
---
V2: No change
V3: No change
V4: Add AB from Rob
V5: No change
---
 .../devicetree/bindings/net/realtek,rtl82xx.yaml          | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/Documentation/devicetree/bindings/net/realtek,rtl82xx.yaml b/Documentation/devicetree/bindings/net/realtek,rtl82xx.yaml
index 2b5697bd7c5df..eafcc2f3e3d66 100644
--- a/Documentation/devicetree/bindings/net/realtek,rtl82xx.yaml
+++ b/Documentation/devicetree/bindings/net/realtek,rtl82xx.yaml
@@ -40,15 +40,15 @@ properties:
 
   leds: true
 
-  realtek,clkout-disable:
+  realtek,aldps-enable:
     type: boolean
     description:
-      Disable CLKOUT clock, CLKOUT clock default is enabled after hardware reset.
+      Enable ALDPS mode, ALDPS mode default is disabled after hardware reset.
 
-  realtek,aldps-enable:
+  realtek,clkout-disable:
     type: boolean
     description:
-      Enable ALDPS mode, ALDPS mode default is disabled after hardware reset.
+      Disable CLKOUT clock, CLKOUT clock default is enabled after hardware reset.
 
   wakeup-source:
     type: boolean
-- 
2.53.0

[net-next,PATCH v5 2/3] dt-bindings: net: realtek,rtl82xx: Document realtek,*-ssc-enable property

[Marek Vasut]

Document support for spread spectrum clocking (SSC) on RTL8211F(D)(I)-CG,
RTL8211FS(I)(-VS)-CG, RTL8211FG(I)(-VS)-CG PHYs. Introduce DT properties
'realtek,clkout-ssc-enable', 'realtek,rxc-ssc-enable' and
'realtek,sysclk-ssc-enable' which control CLKOUT, RXC and SYSCLK
SSC spread spectrum clocking enablement on these signals. These
clock are not exposed via the clock API, therefore assigned-clock-sscs
property does not apply.

Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@oss.qualcomm.com>
Signed-off-by: Marek Vasut <marek.vasut@mailbox.org>
---
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Aleksander Jan Bajkowski <olek2@wp.pl>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Conor Dooley <conor+dt@kernel.org>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Heiner Kallweit <hkallweit1@gmail.com>
Cc: Ivan Galkin <ivan.galkin@axis.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Krzysztof Kozlowski <krzk+dt@kernel.org>
Cc: Michael Klein <michael@fossekall.de>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Vladimir Oltean <vladimir.oltean@nxp.com>
Cc: devicetree@vger.kernel.org
Cc: netdev@vger.kernel.org
---
V2: Split SSC clock control for each CLKOUT, RXC, SYSCLK signal
V3: - Add RB from krzk
    - Update commit subject, use realtek,*-ssc-enable to be accurate
V4: No change
V5: No change
---
 .../devicetree/bindings/net/realtek,rtl82xx.yaml  | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/Documentation/devicetree/bindings/net/realtek,rtl82xx.yaml b/Documentation/devicetree/bindings/net/realtek,rtl82xx.yaml
index eafcc2f3e3d66..45033c31a2d51 100644
--- a/Documentation/devicetree/bindings/net/realtek,rtl82xx.yaml
+++ b/Documentation/devicetree/bindings/net/realtek,rtl82xx.yaml
@@ -50,6 +50,21 @@ properties:
     description:
       Disable CLKOUT clock, CLKOUT clock default is enabled after hardware reset.
 
+  realtek,clkout-ssc-enable:
+    type: boolean
+    description:
+      Enable CLKOUT SSC mode, CLKOUT SSC mode default is disabled after hardware reset.
+
+  realtek,rxc-ssc-enable:
+    type: boolean
+    description:
+      Enable RXC SSC mode, RXC SSC mode default is disabled after hardware reset.
+
+  realtek,sysclk-ssc-enable:
+    type: boolean
+    description:
+      Enable SYSCLK SSC mode, SYSCLK SSC mode default is disabled after hardware reset.
+
   wakeup-source:
     type: boolean
     description:
-- 
2.53.0

[net-next,PATCH v5 3/3] net: phy: realtek: Add property to enable SSC

[Marek Vasut]

Add support for spread spectrum clocking (SSC) on RTL8211F(D)(I)-CG,
RTL8211FS(I)(-VS)-CG, RTL8211FG(I)(-VS)-CG PHYs. The implementation
follows EMI improvement application note Rev. 1.2 for these PHYs.

The current implementation enables SSC for both RXC and SYSCLK clock
signals. Introduce DT properties 'realtek,clkout-ssc-enable',
'realtek,rxc-ssc-enable' and 'realtek,sysclk-ssc-enable' which control
CLKOUT, RXC and SYSCLK SSC spread spectrum clocking enablement on these
signals.

Signed-off-by: Marek Vasut <marek.vasut@mailbox.org>
---
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Aleksander Jan Bajkowski <olek2@wp.pl>
Cc: Andrew Lunn <andrew@lunn.ch>
Cc: Conor Dooley <conor+dt@kernel.org>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Florian Fainelli <f.fainelli@gmail.com>
Cc: Heiner Kallweit <hkallweit1@gmail.com>
Cc: Ivan Galkin <ivan.galkin@axis.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Krzysztof Kozlowski <krzk+dt@kernel.org>
Cc: Michael Klein <michael@fossekall.de>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Rob Herring <robh@kernel.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Vladimir Oltean <vladimir.oltean@nxp.com>
Cc: devicetree@vger.kernel.org
Cc: netdev@vger.kernel.org
---
V2: Split SSC clock control for each CLKOUT, RXC, SYSCLK signal
V3: Update RTL8211FVD PHYCR2 comment to state this PHY has PHYCR2 register,
    but SSC configuration is not supported due to different layout.
V4: - Perform all SSC configuration before disabling CLKOUT
    - Perform all SSC configuration in the same order as in the SSC appnote
    - Rebase on current next, retest using spectrum analyzer again
V5: s@SCC@SSC@ typo
---
 drivers/net/phy/realtek/realtek_main.c | 131 +++++++++++++++++++++++++
 1 file changed, 131 insertions(+)

diff --git a/drivers/net/phy/realtek/realtek_main.c b/drivers/net/phy/realtek/realtek_main.c
index 023e47ad605bd..0b5d35841fdd4 100644
--- a/drivers/net/phy/realtek/realtek_main.c
+++ b/drivers/net/phy/realtek/realtek_main.c
@@ -75,10 +75,18 @@
 
 #define RTL8211F_PHYCR2				0x19
 #define RTL8211F_CLKOUT_EN			BIT(0)
+#define RTL8211F_SYSCLK_SSC_EN			BIT(3)
 #define RTL8211F_PHYCR2_PHY_EEE_ENABLE		BIT(5)
+#define RTL8211F_CLKOUT_SSC_EN			BIT(7)
 
 #define RTL8211F_INSR				0x1d
 
+/* RTL8211F SSC settings */
+#define RTL8211F_SSC_PAGE			0xc44
+#define RTL8211F_SSC_RXC			0x13
+#define RTL8211F_SSC_SYSCLK			0x17
+#define RTL8211F_SSC_CLKOUT			0x19
+
 /* RTL8211F LED configuration */
 #define RTL8211F_LEDCR_PAGE			0xd04
 #define RTL8211F_LEDCR				0x10
@@ -215,6 +223,9 @@ MODULE_LICENSE("GPL");
 struct rtl821x_priv {
 	bool enable_aldps;
 	bool disable_clk_out;
+	bool enable_clkout_ssc;
+	bool enable_rxc_ssc;
+	bool enable_sysclk_ssc;
 	struct clk *clk;
 	/* rtl8211f */
 	u16 iner;
@@ -278,6 +289,12 @@ static int rtl821x_probe(struct phy_device *phydev)
 						   "realtek,aldps-enable");
 	priv->disable_clk_out = of_property_read_bool(dev->of_node,
 						      "realtek,clkout-disable");
+	priv->enable_clkout_ssc = of_property_read_bool(dev->of_node,
+							"realtek,clkout-ssc-enable");
+	priv->enable_rxc_ssc = of_property_read_bool(dev->of_node,
+						     "realtek,rxc-ssc-enable");
+	priv->enable_sysclk_ssc = of_property_read_bool(dev->of_node,
+							"realtek,sysclk-ssc-enable");
 
 	phydev->priv = priv;
 
@@ -707,6 +724,108 @@ static int rtl8211f_config_phy_eee(struct phy_device *phydev)
 			  RTL8211F_PHYCR2_PHY_EEE_ENABLE, 0);
 }
 
+static int rtl8211f_config_clkout_ssc(struct phy_device *phydev)
+{
+	struct rtl821x_priv *priv = phydev->priv;
+	struct device *dev = &phydev->mdio.dev;
+	int ret;
+
+	/* The value is preserved if the device tree property is absent */
+	if (!priv->enable_clkout_ssc)
+		return 0;
+
+	/* RTL8211FVD has PHYCR2 register, but configuration of CLKOUT SSC
+	 * is not currently supported by this driver due to different bit
+	 * layout.
+	 */
+	if (phydev->drv->phy_id == RTL_8211FVD_PHYID)
+		return 0;
+
+	/* Unnamed registers from EMI improvement parameters application note 1.2 */
+	ret = phy_write_paged(phydev, 0xd09, 0x10, 0xcf00);
+	if (ret < 0) {
+		dev_err(dev, "CLKOUT SSC initialization failed: %pe\n", ERR_PTR(ret));
+		return ret;
+	}
+
+	ret = phy_write(phydev, RTL8211F_SSC_CLKOUT, 0x38c3);
+	if (ret < 0) {
+		dev_err(dev, "CLKOUT SSC configuration failed: %pe\n", ERR_PTR(ret));
+		return ret;
+	}
+
+	/*
+	 * Enable CLKOUT SSC using PHYCR2 bit 7 , this step is missing from the
+	 * EMI improvement parameters application note 1.2 section 2.3
+	 */
+	ret = phy_set_bits(phydev, RTL8211F_PHYCR2, RTL8211F_CLKOUT_SSC_EN);
+	if (ret < 0) {
+		dev_err(dev, "CLKOUT SSC enable failed: %pe\n", ERR_PTR(ret));
+		return ret;
+	}
+
+	return 0;
+}
+
+static int rtl8211f_config_rxc_ssc(struct phy_device *phydev)
+{
+	struct rtl821x_priv *priv = phydev->priv;
+	struct device *dev = &phydev->mdio.dev;
+	int ret;
+
+	/* The value is preserved if the device tree property is absent */
+	if (!priv->enable_rxc_ssc)
+		return 0;
+
+	/* RTL8211FVD has PHYCR2 register, but configuration of RXC SSC
+	 * is not currently supported by this driver due to different bit
+	 * layout.
+	 */
+	if (phydev->drv->phy_id == RTL_8211FVD_PHYID)
+		return 0;
+
+	ret = phy_write_paged(phydev, RTL8211F_SSC_PAGE, RTL8211F_SSC_RXC, 0x5f00);
+	if (ret < 0) {
+		dev_err(dev, "RXC SSC configuration failed: %pe\n", ERR_PTR(ret));
+		return ret;
+	}
+
+	return 0;
+}
+
+static int rtl8211f_config_sysclk_ssc(struct phy_device *phydev)
+{
+	struct rtl821x_priv *priv = phydev->priv;
+	struct device *dev = &phydev->mdio.dev;
+	int ret;
+
+	/* The value is preserved if the device tree property is absent */
+	if (!priv->enable_sysclk_ssc)
+		return 0;
+
+	/* RTL8211FVD has PHYCR2 register, but configuration of SYSCLK SSC
+	 * is not currently supported by this driver due to different bit
+	 * layout.
+	 */
+	if (phydev->drv->phy_id == RTL_8211FVD_PHYID)
+		return 0;
+
+	ret = phy_write_paged(phydev, RTL8211F_SSC_PAGE, RTL8211F_SSC_SYSCLK, 0x4f00);
+	if (ret < 0) {
+		dev_err(dev, "SYSCLK SSC configuration failed: %pe\n", ERR_PTR(ret));
+		return ret;
+	}
+
+	/* Enable SSC */
+	ret = phy_set_bits(phydev, RTL8211F_PHYCR2, RTL8211F_SYSCLK_SSC_EN);
+	if (ret < 0) {
+		dev_err(dev, "SYSCLK SSC enable failed: %pe\n", ERR_PTR(ret));
+		return ret;
+	}
+
+	return 0;
+}
+
 static int rtl8211f_config_init(struct phy_device *phydev)
 {
 	struct device *dev = &phydev->mdio.dev;
@@ -723,6 +842,18 @@ static int rtl8211f_config_init(struct phy_device *phydev)
 	if (ret)
 		return ret;
 
+	ret = rtl8211f_config_rxc_ssc(phydev);
+	if (ret)
+		return ret;
+
+	ret = rtl8211f_config_sysclk_ssc(phydev);
+	if (ret)
+		return ret;
+
+	ret = rtl8211f_config_clkout_ssc(phydev);
+	if (ret)
+		return ret;
+
 	ret = rtl8211f_config_clk_out(phydev);
 	if (ret) {
 		dev_err(dev, "clkout configuration failed: %pe\n",
-- 
2.53.0

Re: [net-next,PATCH v5 3/3] net: phy: realtek: Add property to enable SSC

[Jakub Kicinski]

On Thu, 26 Mar 2026 22:06:35 +0100 Marek Vasut wrote:
> +/* RTL8211F SSC settings */
> +#define RTL8211F_SSC_PAGE			0xc44
> +#define RTL8211F_SSC_RXC			0x13
> +#define RTL8211F_SSC_SYSCLK			0x17
> +#define RTL8211F_SSC_CLKOUT			0x19

> +	/* Unnamed registers from EMI improvement parameters application note 1.2 */
> +	ret = phy_write_paged(phydev, 0xd09, 0x10, 0xcf00);
> +	if (ret < 0) {
> +		dev_err(dev, "CLKOUT SSC initialization failed: %pe\n", ERR_PTR(ret));
> +		return ret;
> +	}
> +
> +	ret = phy_write(phydev, RTL8211F_SSC_CLKOUT, 0x38c3);
> +	if (ret < 0) {
> +		dev_err(dev, "CLKOUT SSC configuration failed: %pe\n", ERR_PTR(ret));
> +		return ret;
> +	}

AI flags that this, did you mean to write to the SSC_PAGE here?
-- 
pw-bot: cr

Re: [net-next,PATCH v5 3/3] net: phy: realtek: Add property to enable SSC

[Aleksander Jan Bajkowski]

Hi Marek,


On 26/03/2026 22:06, Marek Vasut wrote:
> Add support for spread spectrum clocking (SSC) on RTL8211F(D)(I)-CG,
> RTL8211FS(I)(-VS)-CG, RTL8211FG(I)(-VS)-CG PHYs. The implementation
> follows EMI improvement application note Rev. 1.2 for these PHYs.
>
> The current implementation enables SSC for both RXC and SYSCLK clock
> signals. Introduce DT properties 'realtek,clkout-ssc-enable',
> 'realtek,rxc-ssc-enable' and 'realtek,sysclk-ssc-enable' which control
> CLKOUT, RXC and SYSCLK SSC spread spectrum clocking enablement on these
> signals.
>
> Signed-off-by: Marek Vasut <marek.vasut@mailbox.org>
> ---
> Cc: "David S. Miller" <davem@davemloft.net>
> Cc: Aleksander Jan Bajkowski <olek2@wp.pl>
> Cc: Andrew Lunn <andrew@lunn.ch>
> Cc: Conor Dooley <conor+dt@kernel.org>
> Cc: Eric Dumazet <edumazet@google.com>
> Cc: Florian Fainelli <f.fainelli@gmail.com>
> Cc: Heiner Kallweit <hkallweit1@gmail.com>
> Cc: Ivan Galkin <ivan.galkin@axis.com>
> Cc: Jakub Kicinski <kuba@kernel.org>
> Cc: Krzysztof Kozlowski <krzk+dt@kernel.org>
> Cc: Michael Klein <michael@fossekall.de>
> Cc: Paolo Abeni <pabeni@redhat.com>
> Cc: Rob Herring <robh@kernel.org>
> Cc: Russell King <linux@armlinux.org.uk>
> Cc: Vladimir Oltean <vladimir.oltean@nxp.com>
> Cc: devicetree@vger.kernel.org
> Cc: netdev@vger.kernel.org
> ---
> V2: Split SSC clock control for each CLKOUT, RXC, SYSCLK signal
> V3: Update RTL8211FVD PHYCR2 comment to state this PHY has PHYCR2 register,
>      but SSC configuration is not supported due to different layout.
> V4: - Perform all SSC configuration before disabling CLKOUT
>      - Perform all SSC configuration in the same order as in the SSC appnote
>      - Rebase on current next, retest using spectrum analyzer again
> V5: s@SCC@SSC@ typo
> ---
>   drivers/net/phy/realtek/realtek_main.c | 131 +++++++++++++++++++++++++
>   1 file changed, 131 insertions(+)
>
> diff --git a/drivers/net/phy/realtek/realtek_main.c b/drivers/net/phy/realtek/realtek_main.c
> index 023e47ad605bd..0b5d35841fdd4 100644
> --- a/drivers/net/phy/realtek/realtek_main.c
> +++ b/drivers/net/phy/realtek/realtek_main.c
> @@ -75,10 +75,18 @@
>   
>   #define RTL8211F_PHYCR2				0x19
>   #define RTL8211F_CLKOUT_EN			BIT(0)
> +#define RTL8211F_SYSCLK_SSC_EN			BIT(3)
>   #define RTL8211F_PHYCR2_PHY_EEE_ENABLE		BIT(5)
> +#define RTL8211F_CLKOUT_SSC_EN			BIT(7)
>   
>   #define RTL8211F_INSR				0x1d
>   
> +/* RTL8211F SSC settings */
> +#define RTL8211F_SSC_PAGE			0xc44
> +#define RTL8211F_SSC_RXC			0x13
> +#define RTL8211F_SSC_SYSCLK			0x17
> +#define RTL8211F_SSC_CLKOUT			0x19
> +
>   /* RTL8211F LED configuration */
>   #define RTL8211F_LEDCR_PAGE			0xd04
>   #define RTL8211F_LEDCR				0x10
> @@ -215,6 +223,9 @@ MODULE_LICENSE("GPL");
>   struct rtl821x_priv {
>   	bool enable_aldps;
>   	bool disable_clk_out;
> +	bool enable_clkout_ssc;
> +	bool enable_rxc_ssc;
> +	bool enable_sysclk_ssc;
>   	struct clk *clk;
>   	/* rtl8211f */
>   	u16 iner;
> @@ -278,6 +289,12 @@ static int rtl821x_probe(struct phy_device *phydev)
>   						   "realtek,aldps-enable");
>   	priv->disable_clk_out = of_property_read_bool(dev->of_node,
>   						      "realtek,clkout-disable");
> +	priv->enable_clkout_ssc = of_property_read_bool(dev->of_node,
> +							"realtek,clkout-ssc-enable");
> +	priv->enable_rxc_ssc = of_property_read_bool(dev->of_node,
> +						     "realtek,rxc-ssc-enable");
> +	priv->enable_sysclk_ssc = of_property_read_bool(dev->of_node,
> +							"realtek,sysclk-ssc-enable");
>   
>   	phydev->priv = priv;
>   
> @@ -707,6 +724,108 @@ static int rtl8211f_config_phy_eee(struct phy_device *phydev)
>   			  RTL8211F_PHYCR2_PHY_EEE_ENABLE, 0);
>   }
>   
> +static int rtl8211f_config_clkout_ssc(struct phy_device *phydev)
> +{
> +	struct rtl821x_priv *priv = phydev->priv;
> +	struct device *dev = &phydev->mdio.dev;
> +	int ret;
> +
> +	/* The value is preserved if the device tree property is absent */
> +	if (!priv->enable_clkout_ssc)
> +		return 0;
> +
> +	/* RTL8211FVD has PHYCR2 register, but configuration of CLKOUT SSC
> +	 * is not currently supported by this driver due to different bit
> +	 * layout.
> +	 */
> +	if (phydev->drv->phy_id == RTL_8211FVD_PHYID)
> +		return 0;
> +
> +	/* Unnamed registers from EMI improvement parameters application note 1.2 */
> +	ret = phy_write_paged(phydev, 0xd09, 0x10, 0xcf00);
> +	if (ret < 0) {
> +		dev_err(dev, "CLKOUT SSC initialization failed: %pe\n", ERR_PTR(ret));
> +		return ret;
> +	}
> +
> +	ret = phy_write(phydev, RTL8211F_SSC_CLKOUT, 0x38c3);

Only registers 0x10–0x17 require paged operations. The remaining registers
are mapped directly into the PHY address space. This is mentioned in commit
650e55f224a575cdb18c984b95036109519502d1. Paged and direct access return
the same results. With this in mind, I believe that RTL8211F_SSC_CLKOUT is
an alias for RTL8211F_PHYCR2 and is described on page 45 of the 
datasheet[1].

1. RTL8211F(I)-CG/RTL8211FD(I)-CG Datasheet

Best Regards,
Aleksander

Re: [net-next,PATCH v5 3/3] net: phy: realtek: Add property to enable SSC

[Marek Vasut]

On 3/31/26 3:57 AM, Jakub Kicinski wrote:
> On Thu, 26 Mar 2026 22:06:35 +0100 Marek Vasut wrote:
>> +/* RTL8211F SSC settings */
>> +#define RTL8211F_SSC_PAGE			0xc44
>> +#define RTL8211F_SSC_RXC			0x13
>> +#define RTL8211F_SSC_SYSCLK			0x17
>> +#define RTL8211F_SSC_CLKOUT			0x19
> 
>> +	/* Unnamed registers from EMI improvement parameters application note 1.2 */
>> +	ret = phy_write_paged(phydev, 0xd09, 0x10, 0xcf00);
>> +	if (ret < 0) {
>> +		dev_err(dev, "CLKOUT SSC initialization failed: %pe\n", ERR_PTR(ret));
>> +		return ret;
>> +	}
>> +
>> +	ret = phy_write(phydev, RTL8211F_SSC_CLKOUT, 0x38c3);
>> +	if (ret < 0) {
>> +		dev_err(dev, "CLKOUT SSC configuration failed: %pe\n", ERR_PTR(ret));
>> +		return ret;
>> +	}
> 
> AI flags that this, did you mean to write to the SSC_PAGE here?

No, see commit 650e55f224a5 ("net: phy: realtek: simplify bogus paged 
operations")

"
     net: phy: realtek: simplify bogus paged operations

     Only registers 0x10~0x17 are affected by the value in the page
     selection register 0x1f. Hence there is no point in using paged
     operations when accessing any other registers.
...
"

Register 0x19 is not affected by paged operations.

Re: [net-next,PATCH v5 3/3] net: phy: realtek: Add property to enable SSC

[Marek Vasut]

On 4/5/26 10:23 PM, Aleksander Jan Bajkowski wrote:

Hi,

>> +static int rtl8211f_config_clkout_ssc(struct phy_device *phydev)
>> +{
>> +    struct rtl821x_priv *priv = phydev->priv;
>> +    struct device *dev = &phydev->mdio.dev;
>> +    int ret;
>> +
>> +    /* The value is preserved if the device tree property is absent */
>> +    if (!priv->enable_clkout_ssc)
>> +        return 0;
>> +
>> +    /* RTL8211FVD has PHYCR2 register, but configuration of CLKOUT SSC
>> +     * is not currently supported by this driver due to different bit
>> +     * layout.
>> +     */
>> +    if (phydev->drv->phy_id == RTL_8211FVD_PHYID)
>> +        return 0;
>> +
>> +    /* Unnamed registers from EMI improvement parameters application 
>> note 1.2 */
>> +    ret = phy_write_paged(phydev, 0xd09, 0x10, 0xcf00);
>> +    if (ret < 0) {
>> +        dev_err(dev, "CLKOUT SSC initialization failed: %pe\n", 
>> ERR_PTR(ret));
>> +        return ret;
>> +    }
>> +
>> +    ret = phy_write(phydev, RTL8211F_SSC_CLKOUT, 0x38c3);
> 
> Only registers 0x10–0x17 require paged operations. The remaining registers
> are mapped directly into the PHY address space. This is mentioned in commit
> 650e55f224a575cdb18c984b95036109519502d1. Paged and direct access return
> the same results. With this in mind, I believe that RTL8211F_SSC_CLKOUT is
> an alias for RTL8211F_PHYCR2 and is described on page 45 of the 
> datasheet[1].
> 
> 1. RTL8211F(I)-CG/RTL8211FD(I)-CG Datasheet
This is a good point indeed, I think I can simply set PHYCR2 bits 
7,12,13 to enable the CLKOUT SSC ?

Re: [net-next,PATCH v5 3/3] net: phy: realtek: Add property to enable SSC

[Aleksander Jan Bajkowski]

Hi Marek,

On 05/04/2026 23:59, Marek Vasut wrote:
> On 4/5/26 10:23 PM, Aleksander Jan Bajkowski wrote:
>
> Hi,
>
>>> +static int rtl8211f_config_clkout_ssc(struct phy_device *phydev)
>>> +{
>>> +    struct rtl821x_priv *priv = phydev->priv;
>>> +    struct device *dev = &phydev->mdio.dev;
>>> +    int ret;
>>> +
>>> +    /* The value is preserved if the device tree property is absent */
>>> +    if (!priv->enable_clkout_ssc)
>>> +        return 0;
>>> +
>>> +    /* RTL8211FVD has PHYCR2 register, but configuration of CLKOUT SSC
>>> +     * is not currently supported by this driver due to different bit
>>> +     * layout.
>>> +     */
>>> +    if (phydev->drv->phy_id == RTL_8211FVD_PHYID)
>>> +        return 0;
>>> +
>>> +    /* Unnamed registers from EMI improvement parameters 
>>> application note 1.2 */
>>> +    ret = phy_write_paged(phydev, 0xd09, 0x10, 0xcf00);
>>> +    if (ret < 0) {
>>> +        dev_err(dev, "CLKOUT SSC initialization failed: %pe\n", 
>>> ERR_PTR(ret));
>>> +        return ret;
>>> +    }
>>> +
>>> +    ret = phy_write(phydev, RTL8211F_SSC_CLKOUT, 0x38c3);
>>
>> Only registers 0x10–0x17 require paged operations. The remaining 
>> registers
>> are mapped directly into the PHY address space. This is mentioned in 
>> commit
>> 650e55f224a575cdb18c984b95036109519502d1. Paged and direct access return
>> the same results. With this in mind, I believe that 
>> RTL8211F_SSC_CLKOUT is
>> an alias for RTL8211F_PHYCR2 and is described on page 45 of the 
>> datasheet[1].
>>
>> 1. RTL8211F(I)-CG/RTL8211FD(I)-CG Datasheet
> This is a good point indeed, I think I can simply set PHYCR2 bits 
> 7,12,13 to enable the CLKOUT SSC ?
Sounds correct.


Regards,
Aleksander