net: phy: marvell10g: report if the PHY fails to boot firmware

[ Upstream commit 3d3ced2ec5d71b99d72ae6910fbdf890bc2eccf0 ]

Some boards do not have the PHY firmware programmed in the 3310's flash,
which leads to the PHY not working as expected.  Warn the user when the
PHY fails to boot the firmware and refuse to initialise.

Fixes: 20b2af32 ("net: phy: add Marvell Alaska X 88X3310 10Gigabit PHY support")
Signed-off-by: NRussell King <rmk+kernel@armlinux.org.uk>
Tested-by: NMaxime Chevallier <maxime.chevallier@bootlin.com>
Reviewed-by: NAndrew Lunn <andrew@lunn.ch>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/net/phy/marvell10g.c

@@ -27,6 +27,9 @@
 #include <linux/phy.h>
 
 enum {
+	MV_PMA_BOOT		= 0xc050,
+	MV_PMA_BOOT_FATAL	= BIT(0),
+
 	MV_PCS_BASE_T		= 0x0000,
 	MV_PCS_BASE_R		= 0x1000,
 	MV_PCS_1000BASEX	= 0x2000,
@@ -226,6 +229,16 @@ static int mv3310_probe(struct phy_device *phydev)
 	    (phydev->c45_ids.devices_in_package & mmd_mask) != mmd_mask)
 		return -ENODEV;
 
+	ret = phy_read_mmd(phydev, MDIO_MMD_PMAPMD, MV_PMA_BOOT);
+	if (ret < 0)
+		return ret;
+
+	if (ret & MV_PMA_BOOT_FATAL) {
+		dev_warn(&phydev->mdio.dev,
+			 "PHY failed to boot firmware, status=%04x\n", ret);
+		return -ENODEV;
+	}
+
 	priv = devm_kzalloc(&phydev->mdio.dev, sizeof(*priv), GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;