Subject: kernel: add at803x fix for sgmii mode
From: Roman Yeryomin <[email-masked]>

Some (possibly broken) bootloaders incorreclty initialize at8033
phy. This patch enables sgmii autonegotiation mode.

[[email-masked]: felix added this to his upstream queue]

Signed-off-by: Roman Yeryomin <[email-masked]>
---
 drivers/net/phy/at803x.c | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

--- a/drivers/net/phy/at803x.c
+++ b/drivers/net/phy/at803x.c
@@ -76,6 +76,7 @@
 #define AT803X_LOC_MAC_ADDR_32_47_OFFSET	0x804A
 #define AT803X_REG_CHIP_CONFIG			0x1f
 #define AT803X_BT_BX_REG_SEL			0x8000
+#define AT803X_SGMII_ANEG_EN			0x1000
 
 #define AT803X_DEBUG_ADDR			0x1D
 #define AT803X_DEBUG_DATA			0x1E
@@ -562,6 +563,27 @@ static int at8031_pll_config(struct phy_
 static int at803x_config_init(struct phy_device *phydev)
 {
 	int ret;
+	u32 v;
+
+	if (phydev->drv->phy_id == ATH8031_PHY_ID &&
+		phydev->interface == PHY_INTERFACE_MODE_SGMII)
+	{
+		v = phy_read(phydev, AT803X_REG_CHIP_CONFIG);
+		/* select SGMII/fiber page */
+		ret = phy_write(phydev, AT803X_REG_CHIP_CONFIG,
+						v & ~AT803X_BT_BX_REG_SEL);
+		if (ret)
+			return ret;
+		/* enable SGMII autonegotiation */
+		ret = phy_write(phydev, MII_BMCR, AT803X_SGMII_ANEG_EN);
+		if (ret)
+			return ret;
+		/* select copper page */
+		ret = phy_write(phydev, AT803X_REG_CHIP_CONFIG,
+						v | AT803X_BT_BX_REG_SEL);
+		if (ret)
+			return ret;
+	}
 
 	/* The RX and TX delay default is:
 	 *   after HW reset: RX delay enabled and TX delay disabled