[PATCH net-next 0/2] at803x fiber/SFP support

[PATCH net-next 0/2] at803x fiber/SFP support

[Robert Hancock]

Add support for 1000Base-X fiber modes to the at803x PHY driver, as
well as support for connecting a downstream SFP cage.

Robert Hancock (2):
  net: phy: at803x: add fiber support
  net: phy: at803x: Support downstream SFP cage

 drivers/net/phy/at803x.c | 122 +++++++++++++++++++++++++++++++++++----
 1 file changed, 112 insertions(+), 10 deletions(-)

-- 
2.27.0

[PATCH net-next 1/2] net: phy: at803x: add fiber support

[Robert Hancock]

Previously this driver always forced the copper page to be selected,
however for AR8031 in 100Base-FX or 1000Base-X modes, the fiber page
needs to be selected. Set the appropriate mode based on the hardware
mode_cfg strap selection.

Enable the appropriate interrupt bits to detect fiber-side link up
or down events.

Update config_aneg and read_status methods to use the appropriate
Clause 37 calls when fiber mode is in use.

Signed-off-by: Robert Hancock <robert.hancock@calian.com>
---
 drivers/net/phy/at803x.c | 69 ++++++++++++++++++++++++++++++++++------
 1 file changed, 59 insertions(+), 10 deletions(-)

diff --git a/drivers/net/phy/at803x.c b/drivers/net/phy/at803x.c
index 5d62b85a4024..65f546eca5f4 100644
--- a/drivers/net/phy/at803x.c
+++ b/drivers/net/phy/at803x.c
@@ -48,6 +48,8 @@
 #define AT803X_INTR_ENABLE_PAGE_RECEIVED	BIT(12)
 #define AT803X_INTR_ENABLE_LINK_FAIL		BIT(11)
 #define AT803X_INTR_ENABLE_LINK_SUCCESS		BIT(10)
+#define AT803X_INTR_ENABLE_LINK_FAIL_BX		BIT(8)
+#define AT803X_INTR_ENABLE_LINK_SUCCESS_BX	BIT(7)
 #define AT803X_INTR_ENABLE_WIRESPEED_DOWNGRADE	BIT(5)
 #define AT803X_INTR_ENABLE_POLARITY_CHANGED	BIT(1)
 #define AT803X_INTR_ENABLE_WOL			BIT(0)
@@ -81,7 +83,17 @@
 #define AT803X_DEBUG_DATA			0x1E
 
 #define AT803X_MODE_CFG_MASK			0x0F
-#define AT803X_MODE_CFG_SGMII			0x01
+#define AT803X_MODE_CFG_BASET_RGMII		0x00
+#define AT803X_MODE_CFG_BASET_SGMII		0x01
+#define AT803X_MODE_CFG_BX1000_RGMII_50		0x02
+#define AT803X_MODE_CFG_BX1000_RGMII_75		0x03
+#define AT803X_MODE_CFG_BX1000_CONV_50		0x04
+#define AT803X_MODE_CFG_BX1000_CONV_75		0x05
+#define AT803X_MODE_CFG_FX100_RGMII_50		0x06
+#define AT803X_MODE_CFG_FX100_CONV_50		0x07
+#define AT803X_MODE_CFG_RGMII_AUTO_MDET		0x0B
+#define AT803X_MODE_CFG_FX100_RGMII_75		0x0E
+#define AT803X_MODE_CFG_FX100_CONV_75		0x0F
 
 #define AT803X_PSSR				0x11	/*PHY-Specific Status Register*/
 #define AT803X_PSSR_MR_AN_COMPLETE		0x0200
@@ -191,6 +203,8 @@ struct at803x_priv {
 	u16 clk_25m_mask;
 	u8 smarteee_lpi_tw_1g;
 	u8 smarteee_lpi_tw_100m;
+	bool is_fiber;
+	bool is_1000basex;
 	struct regulator_dev *vddio_rdev;
 	struct regulator_dev *vddh_rdev;
 	struct regulator *vddio;
@@ -673,12 +687,32 @@ static int at803x_probe(struct phy_device *phydev)
 	}
 
 	/* Some bootloaders leave the fiber page selected.
-	 * Switch to the copper page, as otherwise we read
-	 * the PHY capabilities from the fiber side.
+	 * Switch to the appropriate page (fiber or copper), as otherwise we
+	 * read the PHY capabilities from the wrong page.
 	 */
 	if (at803x_match_phy_id(phydev, ATH8031_PHY_ID)) {
+		int mode_cfg;
+
+		ret = phy_read(phydev, AT803X_REG_CHIP_CONFIG);
+		if (ret < 0)
+			goto err;
+		mode_cfg = ret & AT803X_MODE_CFG_MASK;
+
+		switch (mode_cfg) {
+		case AT803X_MODE_CFG_BX1000_RGMII_50:
+		case AT803X_MODE_CFG_BX1000_RGMII_75:
+			priv->is_1000basex = true;
+			fallthrough;
+		case AT803X_MODE_CFG_FX100_RGMII_50:
+		case AT803X_MODE_CFG_FX100_RGMII_75:
+			priv->is_fiber = true;
+			break;
+		}
+
 		phy_lock_mdio_bus(phydev);
-		ret = at803x_write_page(phydev, AT803X_PAGE_COPPER);
+		ret = at803x_write_page(phydev,
+					priv->is_fiber ? AT803X_PAGE_FIBER :
+							 AT803X_PAGE_COPPER);
 		phy_unlock_mdio_bus(phydev);
 		if (ret)
 			goto err;
@@ -703,6 +737,7 @@ static void at803x_remove(struct phy_device *phydev)
 
 static int at803x_get_features(struct phy_device *phydev)
 {
+	struct at803x_priv *priv = phydev->priv;
 	int err;
 
 	err = genphy_read_abilities(phydev);
@@ -720,12 +755,13 @@ static int at803x_get_features(struct phy_device *phydev)
 	 * As a result of that, ESTATUS_1000_XFULL is set
 	 * to 1 even when operating in copper TP mode.
 	 *
-	 * Remove this mode from the supported link modes,
-	 * as this driver currently only supports copper
-	 * operation.
+	 * Remove this mode from the supported link modes
+	 * when the device is configured for copper operation.
 	 */
-	linkmode_clear_bit(ETHTOOL_LINK_MODE_1000baseX_Full_BIT,
-			   phydev->supported);
+	if (!priv->is_1000basex)
+		linkmode_clear_bit(ETHTOOL_LINK_MODE_1000baseX_Full_BIT,
+				   phydev->supported);
+
 	return 0;
 }
 
@@ -846,6 +882,7 @@ static int at803x_ack_interrupt(struct phy_device *phydev)
 
 static int at803x_config_intr(struct phy_device *phydev)
 {
+	struct at803x_priv *priv = phydev->priv;
 	int err;
 	int value;
 
@@ -862,6 +899,10 @@ static int at803x_config_intr(struct phy_device *phydev)
 		value |= AT803X_INTR_ENABLE_DUPLEX_CHANGED;
 		value |= AT803X_INTR_ENABLE_LINK_FAIL;
 		value |= AT803X_INTR_ENABLE_LINK_SUCCESS;
+		if (priv->is_fiber) {
+			value |= AT803X_INTR_ENABLE_LINK_FAIL_BX;
+			value |= AT803X_INTR_ENABLE_LINK_SUCCESS_BX;
+		}
 
 		err = phy_write(phydev, AT803X_INTR_ENABLE, value);
 	} else {
@@ -929,8 +970,12 @@ static void at803x_link_change_notify(struct phy_device *phydev)
 
 static int at803x_read_status(struct phy_device *phydev)
 {
+	struct at803x_priv *priv = phydev->priv;
 	int ss, err, old_link = phydev->link;
 
+	if (priv->is_1000basex)
+		return genphy_c37_read_status(phydev);
+
 	/* Update the link, but return if there was an error */
 	err = genphy_update_link(phydev);
 	if (err)
@@ -1029,6 +1074,7 @@ static int at803x_config_mdix(struct phy_device *phydev, u8 ctrl)
 
 static int at803x_config_aneg(struct phy_device *phydev)
 {
+	struct at803x_priv *priv = phydev->priv;
 	int ret;
 
 	ret = at803x_config_mdix(phydev, phydev->mdix_ctrl);
@@ -1045,7 +1091,10 @@ static int at803x_config_aneg(struct phy_device *phydev)
 			return ret;
 	}
 
-	return genphy_config_aneg(phydev);
+	if (priv->is_1000basex)
+		return genphy_c37_config_aneg(phydev);
+	else
+		return genphy_config_aneg(phydev);
 }
 
 static int at803x_get_downshift(struct phy_device *phydev, u8 *d)
-- 
2.27.0

[PATCH net-next 2/2] net: phy: at803x: Support downstream SFP cage

[Robert Hancock]

Add support for downstream SFP cages for AR8031 and AR8033. This is
primarily intended for fiber modules or direct-attach cables, however
copper modules which work in 1000Base-X mode may also function. Such
modules are allowed with a warning.

Signed-off-by: Robert Hancock <robert.hancock@calian.com>
---
 drivers/net/phy/at803x.c | 53 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 53 insertions(+)

diff --git a/drivers/net/phy/at803x.c b/drivers/net/phy/at803x.c
index 65f546eca5f4..b613e26b6b16 100644
--- a/drivers/net/phy/at803x.c
+++ b/drivers/net/phy/at803x.c
@@ -19,6 +19,8 @@
 #include <linux/regulator/of_regulator.h>
 #include <linux/regulator/driver.h>
 #include <linux/regulator/consumer.h>
+#include <linux/phylink.h>
+#include <linux/sfp.h>
 #include <dt-bindings/net/qca-ar803x.h>
 
 #define AT803X_SPECIFIC_FUNCTION_CONTROL	0x10
@@ -552,6 +554,51 @@ static bool at803x_match_phy_id(struct phy_device *phydev, u32 phy_id)
 		== (phy_id & phydev->drv->phy_id_mask);
 }
 
+static int at803x_sfp_insert(void *upstream, const struct sfp_eeprom_id *id)
+{
+	struct phy_device *phydev = upstream;
+	__ETHTOOL_DECLARE_LINK_MODE_MASK(phy_support);
+	__ETHTOOL_DECLARE_LINK_MODE_MASK(sfp_support);
+	phy_interface_t iface;
+
+	linkmode_zero(phy_support);
+	phylink_set(phy_support, 1000baseX_Full);
+	phylink_set(phy_support, 1000baseT_Full);
+	phylink_set(phy_support, Autoneg);
+	phylink_set(phy_support, Pause);
+	phylink_set(phy_support, Asym_Pause);
+
+	linkmode_zero(sfp_support);
+	sfp_parse_support(phydev->sfp_bus, id, sfp_support);
+	/* Some modules support 10G modes as well as others we support.
+	 * Mask out non-supported modes so the correct interface is picked.
+	 */
+	linkmode_and(sfp_support, phy_support, sfp_support);
+
+	iface = sfp_select_interface(phydev->sfp_bus, sfp_support);
+
+	/* Only 1000Base-X is supported by AR8031/8033 as the downstream SerDes
+	 * interface for use with SFP modules.
+	 * However, some copper modules detected as having a preferred SGMII
+	 * interface do default to and function in 1000Base-X mode, so just
+	 * print a warning and allow such modules, as they may have some chance
+	 * of working.
+	 */
+	if (iface == PHY_INTERFACE_MODE_SGMII) {
+		dev_warn(&phydev->mdio.dev, "module may not function if 1000Base-X not supported\n");
+	} else if (iface != PHY_INTERFACE_MODE_1000BASEX) {
+		dev_err(&phydev->mdio.dev, "incompatible SFP module inserted\n");
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static const struct sfp_upstream_ops at803x_sfp_ops = {
+	.attach = phy_sfp_attach,
+	.detach = phy_sfp_detach,
+	.module_insert = at803x_sfp_insert,
+};
+
 static int at803x_parse_dt(struct phy_device *phydev)
 {
 	struct device_node *node = phydev->mdio.dev.of_node;
@@ -716,6 +763,12 @@ static int at803x_probe(struct phy_device *phydev)
 		phy_unlock_mdio_bus(phydev);
 		if (ret)
 			goto err;
+
+		if (priv->is_1000basex) {
+			ret = phy_sfp_probe(phydev, &at803x_sfp_ops);
+			if (ret < 0)
+				goto err;
+		}
 	}
 
 	return 0;
-- 
2.27.0

Re: [PATCH net-next 1/2] net: phy: at803x: add fiber support

[Russell King (Oracle)]

On Wed, Jun 30, 2021 at 12:01:45PM -0600, Robert Hancock wrote:
> Previously this driver always forced the copper page to be selected,
> however for AR8031 in 100Base-FX or 1000Base-X modes, the fiber page
> needs to be selected. Set the appropriate mode based on the hardware
> mode_cfg strap selection.
> 
> Enable the appropriate interrupt bits to detect fiber-side link up
> or down events.
> 
> Update config_aneg and read_status methods to use the appropriate
> Clause 37 calls when fiber mode is in use.
> 
> Signed-off-by: Robert Hancock <robert.hancock@calian.com>
> ---
>  drivers/net/phy/at803x.c | 69 ++++++++++++++++++++++++++++++++++------
>  1 file changed, 59 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/net/phy/at803x.c b/drivers/net/phy/at803x.c
> index 5d62b85a4024..65f546eca5f4 100644
> --- a/drivers/net/phy/at803x.c
> +++ b/drivers/net/phy/at803x.c
> @@ -48,6 +48,8 @@
>  #define AT803X_INTR_ENABLE_PAGE_RECEIVED	BIT(12)
>  #define AT803X_INTR_ENABLE_LINK_FAIL		BIT(11)
>  #define AT803X_INTR_ENABLE_LINK_SUCCESS		BIT(10)
> +#define AT803X_INTR_ENABLE_LINK_FAIL_BX		BIT(8)
> +#define AT803X_INTR_ENABLE_LINK_SUCCESS_BX	BIT(7)
>  #define AT803X_INTR_ENABLE_WIRESPEED_DOWNGRADE	BIT(5)
>  #define AT803X_INTR_ENABLE_POLARITY_CHANGED	BIT(1)
>  #define AT803X_INTR_ENABLE_WOL			BIT(0)
> @@ -81,7 +83,17 @@
>  #define AT803X_DEBUG_DATA			0x1E
>  
>  #define AT803X_MODE_CFG_MASK			0x0F
> -#define AT803X_MODE_CFG_SGMII			0x01
> +#define AT803X_MODE_CFG_BASET_RGMII		0x00
> +#define AT803X_MODE_CFG_BASET_SGMII		0x01
> +#define AT803X_MODE_CFG_BX1000_RGMII_50		0x02
> +#define AT803X_MODE_CFG_BX1000_RGMII_75		0x03
> +#define AT803X_MODE_CFG_BX1000_CONV_50		0x04
> +#define AT803X_MODE_CFG_BX1000_CONV_75		0x05
> +#define AT803X_MODE_CFG_FX100_RGMII_50		0x06
> +#define AT803X_MODE_CFG_FX100_CONV_50		0x07
> +#define AT803X_MODE_CFG_RGMII_AUTO_MDET		0x0B
> +#define AT803X_MODE_CFG_FX100_RGMII_75		0x0E
> +#define AT803X_MODE_CFG_FX100_CONV_75		0x0F
>  
>  #define AT803X_PSSR				0x11	/*PHY-Specific Status Register*/
>  #define AT803X_PSSR_MR_AN_COMPLETE		0x0200
> @@ -191,6 +203,8 @@ struct at803x_priv {
>  	u16 clk_25m_mask;
>  	u8 smarteee_lpi_tw_1g;
>  	u8 smarteee_lpi_tw_100m;
> +	bool is_fiber;
> +	bool is_1000basex;
>  	struct regulator_dev *vddio_rdev;
>  	struct regulator_dev *vddh_rdev;
>  	struct regulator *vddio;
> @@ -673,12 +687,32 @@ static int at803x_probe(struct phy_device *phydev)
>  	}
>  
>  	/* Some bootloaders leave the fiber page selected.
> -	 * Switch to the copper page, as otherwise we read
> -	 * the PHY capabilities from the fiber side.
> +	 * Switch to the appropriate page (fiber or copper), as otherwise we
> +	 * read the PHY capabilities from the wrong page.
>  	 */
>  	if (at803x_match_phy_id(phydev, ATH8031_PHY_ID)) {
> +		int mode_cfg;
> +
> +		ret = phy_read(phydev, AT803X_REG_CHIP_CONFIG);
> +		if (ret < 0)
> +			goto err;
> +		mode_cfg = ret & AT803X_MODE_CFG_MASK;
> +
> +		switch (mode_cfg) {
> +		case AT803X_MODE_CFG_BX1000_RGMII_50:
> +		case AT803X_MODE_CFG_BX1000_RGMII_75:
> +			priv->is_1000basex = true;
> +			fallthrough;
> +		case AT803X_MODE_CFG_FX100_RGMII_50:
> +		case AT803X_MODE_CFG_FX100_RGMII_75:
> +			priv->is_fiber = true;
> +			break;
> +		}
> +
>  		phy_lock_mdio_bus(phydev);
> -		ret = at803x_write_page(phydev, AT803X_PAGE_COPPER);
> +		ret = at803x_write_page(phydev,
> +					priv->is_fiber ? AT803X_PAGE_FIBER :
> +							 AT803X_PAGE_COPPER);
>  		phy_unlock_mdio_bus(phydev);

Does this configuration have to be restored when the PHY is resumed,
or can we assume that this is always retained? Should this be moved
to the config_init method?

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!

Re: [PATCH net-next 2/2] net: phy: at803x: Support downstream SFP cage

[Russell King (Oracle)]

On Wed, Jun 30, 2021 at 12:01:46PM -0600, Robert Hancock wrote:
> Add support for downstream SFP cages for AR8031 and AR8033. This is
> primarily intended for fiber modules or direct-attach cables, however
> copper modules which work in 1000Base-X mode may also function. Such
> modules are allowed with a warning.

Possibly that's because they default to 1000Base-X mode for
compatibility, but there are some (MikroTik S-RJ01) for example
where the PHY definitely is in SGMII mode and will negotiate
10/100Mbit on its media side which won't work with an AR803x.

> +	/* Some modules support 10G modes as well as others we support.
> +	 * Mask out non-supported modes so the correct interface is picked.
> +	 */
> +	linkmode_and(sfp_support, phy_support, sfp_support);

I think rather than relying on sfp_select_interface() complaining when
sfp_support is empty, do an explicit check here (phylink code
effectively does this via the phylink_validate() check.)

You'll then either be given SGMII or 1000BASE-X by
sfp_select_interface().

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
FTTP is here! 40Mbps down 10Mbps up. Decent connectivity at last!