net: phy: marvell: add SFP support for 88E1510

Add support for SFP cages connected to the Marvell 88E1512 transceiver.
88E1512 supports for SGMII/1000Base-X/100Base-FX media type with RGMII
on system interface. Configure PHY to appropriate mode depending on the
type of SFP inserted. On SFP removal configure PHY to the RGMII-copper
mode so RJ-45 port can still work.

Signed-off-by: Ivan Bornyakov <i.bornyakov@metrotek.ru>
Link: https://lore.kernel.org/r/20210812134256.2436-1-i.bornyakov@metrotek.ru
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/phy/marvell.c

@@ -32,6 +32,7 @@
 #include <linux/marvell_phy.h>
 #include <linux/bitfield.h>
 #include <linux/of.h>
+#include <linux/sfp.h>
 
 #include <linux/io.h>
 #include <asm/irq.h>
@@ -46,6 +47,7 @@
 #define MII_MARVELL_MISC_TEST_PAGE	0x06
 #define MII_MARVELL_VCT7_PAGE		0x07
 #define MII_MARVELL_WOL_PAGE		0x11
+#define MII_MARVELL_MODE_PAGE		0x12
 
 #define MII_M1011_IEVENT		0x13
 #define MII_M1011_IEVENT_CLEAR		0x0000
@@ -176,7 +178,14 @@
 
 #define MII_88E1510_GEN_CTRL_REG_1		0x14
 #define MII_88E1510_GEN_CTRL_REG_1_MODE_MASK	0x7
+#define MII_88E1510_GEN_CTRL_REG_1_MODE_RGMII	0x0	/* RGMII to copper */
 #define MII_88E1510_GEN_CTRL_REG_1_MODE_SGMII	0x1	/* SGMII to copper */
+/* RGMII to 1000BASE-X */
+#define MII_88E1510_GEN_CTRL_REG_1_MODE_RGMII_1000X	0x2
+/* RGMII to 100BASE-FX */
+#define MII_88E1510_GEN_CTRL_REG_1_MODE_RGMII_100FX	0x3
+/* RGMII to SGMII */
+#define MII_88E1510_GEN_CTRL_REG_1_MODE_RGMII_SGMII	0x4
 #define MII_88E1510_GEN_CTRL_REG_1_RESET	0x8000	/* Soft reset */
 
 #define MII_VCT5_TX_RX_MDI0_COUPLING	0x10
@@ -2701,6 +2710,100 @@ static int marvell_probe(struct phy_device *phydev)
 	return marvell_hwmon_probe(phydev);
 }
 
+static int m88e1510_sfp_insert(void *upstream, const struct sfp_eeprom_id *id)
+{
+	struct phy_device *phydev = upstream;
+	phy_interface_t interface;
+	struct device *dev;
+	int oldpage;
+	int ret = 0;
+	u16 mode;
+
+	__ETHTOOL_DECLARE_LINK_MODE_MASK(supported) = { 0, };
+
+	dev = &phydev->mdio.dev;
+
+	sfp_parse_support(phydev->sfp_bus, id, supported);
+	interface = sfp_select_interface(phydev->sfp_bus, supported);
+
+	dev_info(dev, "%s SFP module inserted\n", phy_modes(interface));
+
+	switch (interface) {
+	case PHY_INTERFACE_MODE_1000BASEX:
+		mode = MII_88E1510_GEN_CTRL_REG_1_MODE_RGMII_1000X;
+
+		break;
+	case PHY_INTERFACE_MODE_100BASEX:
+		mode = MII_88E1510_GEN_CTRL_REG_1_MODE_RGMII_100FX;
+
+		break;
+	case PHY_INTERFACE_MODE_SGMII:
+		mode = MII_88E1510_GEN_CTRL_REG_1_MODE_RGMII_SGMII;
+
+		break;
+	default:
+		dev_err(dev, "Incompatible SFP module inserted\n");
+
+		return -EINVAL;
+	}
+
+	oldpage = phy_select_page(phydev, MII_MARVELL_MODE_PAGE);
+	if (oldpage < 0)
+		goto error;
+
+	ret = __phy_modify(phydev, MII_88E1510_GEN_CTRL_REG_1,
+			   MII_88E1510_GEN_CTRL_REG_1_MODE_MASK, mode);
+	if (ret < 0)
+		goto error;
+
+	ret = __phy_set_bits(phydev, MII_88E1510_GEN_CTRL_REG_1,
+			     MII_88E1510_GEN_CTRL_REG_1_RESET);
+
+error:
+	return phy_restore_page(phydev, oldpage, ret);
+}
+
+static void m88e1510_sfp_remove(void *upstream)
+{
+	struct phy_device *phydev = upstream;
+	int oldpage;
+	int ret = 0;
+
+	oldpage = phy_select_page(phydev, MII_MARVELL_MODE_PAGE);
+	if (oldpage < 0)
+		goto error;
+
+	ret = __phy_modify(phydev, MII_88E1510_GEN_CTRL_REG_1,
+			   MII_88E1510_GEN_CTRL_REG_1_MODE_MASK,
+			   MII_88E1510_GEN_CTRL_REG_1_MODE_RGMII);
+	if (ret < 0)
+		goto error;
+
+	ret = __phy_set_bits(phydev, MII_88E1510_GEN_CTRL_REG_1,
+			     MII_88E1510_GEN_CTRL_REG_1_RESET);
+
+error:
+	phy_restore_page(phydev, oldpage, ret);
+}
+
+static const struct sfp_upstream_ops m88e1510_sfp_ops = {
+	.module_insert = m88e1510_sfp_insert,
+	.module_remove = m88e1510_sfp_remove,
+	.attach = phy_sfp_attach,
+	.detach = phy_sfp_detach,
+};
+
+static int m88e1510_probe(struct phy_device *phydev)
+{
+	int err;
+
+	err = marvell_probe(phydev);
+	if (err)
+		return err;
+
+	return phy_sfp_probe(phydev, &m88e1510_sfp_ops);
+}
+
 static struct phy_driver marvell_drivers[] = {
 	{
 		.phy_id = MARVELL_PHY_ID_88E1101,
@@ -2927,7 +3030,7 @@ static struct phy_driver marvell_drivers[] = {
 		.driver_data = DEF_MARVELL_HWMON_OPS(m88e1510_hwmon_ops),
 		.features = PHY_GBIT_FIBRE_FEATURES,
 		.flags = PHY_POLL_CABLE_TEST,
-		.probe = marvell_probe,
+		.probe = m88e1510_probe,
 		.config_init = m88e1510_config_init,
 		.config_aneg = m88e1510_config_aneg,
 		.read_status = marvell_read_status,