net: phy: bcm7xxx: Implement EGPHY workaround for 7278

Implement the HW design team recommended workaround in for 7278. Since
the GPHY now returns its revision information in MII_PHYS_ID[23] we need
to check whether the revision provided in flags is 0 or not.
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/phy/bcm7xxx.c

@@ -167,6 +167,31 @@ static int bcm7xxx_28nm_e0_plus_afe_config_init(struct phy_device *phydev)
 	return 0;
 }
 
+static int bcm7xxx_28nm_a0_patch_afe_config_init(struct phy_device *phydev)
+{
+	/* +1 RC_CAL codes for RL centering for both LT and HT conditions */
+	bcm_phy_write_misc(phydev, AFE_RXCONFIG_2, 0xd003);
+
+	/* Cut master bias current by 2% to compensate for RC_CAL offset */
+	bcm_phy_write_misc(phydev, DSP_TAP10, 0x791b);
+
+	/* Improve hybrid leakage */
+	bcm_phy_write_misc(phydev, AFE_HPF_TRIM_OTHERS, 0x10e3);
+
+	/* Change rx_on_tune 8 to 0xf */
+	bcm_phy_write_misc(phydev, 0x21, 0x2, 0x87f6);
+
+	/* Change 100Tx EEE bandwidth */
+	bcm_phy_write_misc(phydev, 0x22, 0x2, 0x017d);
+
+	/* Enable ffe zero detection for Vitesse interoperability */
+	bcm_phy_write_misc(phydev, 0x26, 0x2, 0x0015);
+
+	r_rc_cal_reset(phydev);
+
+	return 0;
+}
+
 static int bcm7xxx_28nm_config_init(struct phy_device *phydev)
 {
 	u8 rev = PHY_BRCM_7XXX_REV(phydev->dev_flags);
@@ -174,6 +199,12 @@ static int bcm7xxx_28nm_config_init(struct phy_device *phydev)
 	u8 count;
 	int ret = 0;
 
+	/* Newer devices have moved the revision information back into a
+	 * standard location in MII_PHYS_ID[23]
+	 */
+	if (rev == 0)
+		rev = phydev->phy_id & ~phydev->drv->phy_id_mask;
+
 	pr_info_once("%s: %s PHY revision: 0x%02x, patch: %d\n",
 		     phydev_name(phydev), phydev->drv->name, rev, patch);
 
@@ -197,6 +228,9 @@ static int bcm7xxx_28nm_config_init(struct phy_device *phydev)
 	case 0x10:
 		ret = bcm7xxx_28nm_e0_plus_afe_config_init(phydev);
 		break;
+	case 0x01:
+		ret = bcm7xxx_28nm_a0_patch_afe_config_init(phydev);
+		break;
 	default:
 		break;
 	}