net: bcmgenet: reserved phy revisions must be checked first

BugLink: http://bugs.launchpad.net/bugs/1745052

[ Upstream commit eca4bad7 ]

The reserved gphy_rev value of 0x01ff must be tested before the old
or new scheme for GPHY major versioning are tested, otherwise it will
be treated as 0xff00 according to the old scheme.

Fixes: b04a2f5b ("net: bcmgenet: add support for new GENET PHY revision scheme")
Signed-off-by: Doug Berger <opendmb@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Khalid Elmously <khalid.elmously@canonical.com>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>

drivers/net/ethernet/broadcom/genet/bcmgenet.c

@@ -3326,6 +3326,12 @@ static void bcmgenet_set_hw_params(struct bcmgenet_priv *priv)
 	 */
 	gphy_rev = reg & 0xffff;
 
+	/* This is reserved so should require special treatment */
+	if (gphy_rev == 0 || gphy_rev == 0x01ff) {
+		pr_warn("Invalid GPHY revision detected: 0x%04x\n", gphy_rev);
+		return;
+	}
+
 	/* This is the good old scheme, just GPHY major, no minor nor patch */
 	if ((gphy_rev & 0xf0) != 0)
 		priv->gphy_rev = gphy_rev << 8;
@@ -3334,12 +3340,6 @@ static void bcmgenet_set_hw_params(struct bcmgenet_priv *priv)
 	else if ((gphy_rev & 0xff00) != 0)
 		priv->gphy_rev = gphy_rev;
 
-	/* This is reserved so should require special treatment */
-	else if (gphy_rev == 0 || gphy_rev == 0x01ff) {
-		pr_warn("Invalid GPHY revision detected: 0x%04x\n", gphy_rev);
-		return;
-	}
-
 #ifdef CONFIG_PHYS_ADDR_T_64BIT
 	if (!(params->flags & GENET_HAS_40BITS))
 		pr_warn("GENET does not support 40-bits PA\n");