diff --git a/net/dsa/port.c b/net/dsa/port.c
index bd0cb38a63f69aa89fbfd7766d960f0c39f11ba0..7afc35db0c29c0cb4c70294e2ea1963f4e2ab9cb 100644
--- a/net/dsa/port.c
+++ b/net/dsa/port.c
@@ -1653,22 +1653,184 @@ static int dsa_shared_port_phylink_register(struct dsa_port *dp)
 	return err;
 }
 
+/* During the initial DSA driver migration to OF, port nodes were sometimes
+ * added to device trees with no indication of how they should operate from a
+ * link management perspective (phy-handle, fixed-link, etc). Additionally, the
+ * phy-mode may be absent. The interpretation of these port OF nodes depends on
+ * their type.
+ *
+ * User ports with no phy-handle or fixed-link are expected to connect to an
+ * internal PHY located on the ds->slave_mii_bus at an MDIO address equal to
+ * the port number. This description is still actively supported.
+ *
+ * Shared (CPU and DSA) ports with no phy-handle or fixed-link are expected to
+ * operate at the maximum speed that their phy-mode is capable of. If the
+ * phy-mode is absent, they are expected to operate using the phy-mode
+ * supported by the port that gives the highest link speed. It is unspecified
+ * if the port should use flow control or not, half duplex or full duplex, or
+ * if the phy-mode is a SERDES link, whether in-band autoneg is expected to be
+ * enabled or not.
+ *
+ * In the latter case of shared ports, omitting the link management description
+ * from the firmware node is deprecated and strongly discouraged. DSA uses
+ * phylink, which rejects the firmware nodes of these ports for lacking
+ * required properties.
+ *
+ * For switches in this table, DSA will skip enforcing validation and will
+ * later omit registering a phylink instance for the shared ports, if they lack
+ * a fixed-link, a phy-handle, or a managed = "in-band-status" property.
+ * It becomes the responsibility of the driver to ensure that these ports
+ * operate at the maximum speed (whatever this means) and will interoperate
+ * with the DSA master or other cascade port, since phylink methods will not be
+ * invoked for them.
+ *
+ * If you are considering expanding this table for newly introduced switches,
+ * think again. It is OK to remove switches from this table if there aren't DT
+ * blobs in circulation which rely on defaulting the shared ports.
+ */
+static const char * const dsa_switches_apply_workarounds[] = {
+#if IS_ENABLED(CONFIG_NET_DSA_XRS700X)
+	"arrow,xrs7003e",
+	"arrow,xrs7003f",
+	"arrow,xrs7004e",
+	"arrow,xrs7004f",
+#endif
+#if IS_ENABLED(CONFIG_B53)
+	"brcm,bcm5325",
+	"brcm,bcm53115",
+	"brcm,bcm53125",
+	"brcm,bcm53128",
+	"brcm,bcm5365",
+	"brcm,bcm5389",
+	"brcm,bcm5395",
+	"brcm,bcm5397",
+	"brcm,bcm5398",
+	"brcm,bcm53010-srab",
+	"brcm,bcm53011-srab",
+	"brcm,bcm53012-srab",
+	"brcm,bcm53018-srab",
+	"brcm,bcm53019-srab",
+	"brcm,bcm5301x-srab",
+	"brcm,bcm11360-srab",
+	"brcm,bcm58522-srab",
+	"brcm,bcm58525-srab",
+	"brcm,bcm58535-srab",
+	"brcm,bcm58622-srab",
+	"brcm,bcm58623-srab",
+	"brcm,bcm58625-srab",
+	"brcm,bcm88312-srab",
+	"brcm,cygnus-srab",
+	"brcm,nsp-srab",
+	"brcm,omega-srab",
+	"brcm,bcm3384-switch",
+	"brcm,bcm6328-switch",
+	"brcm,bcm6368-switch",
+	"brcm,bcm63xx-switch",
+#endif
+#if IS_ENABLED(CONFIG_NET_DSA_BCM_SF2)
+	"brcm,bcm7445-switch-v4.0",
+	"brcm,bcm7278-switch-v4.0",
+	"brcm,bcm7278-switch-v4.8",
+#endif
+#if IS_ENABLED(CONFIG_NET_DSA_LANTIQ_GSWIP)
+	"lantiq,xrx200-gswip",
+	"lantiq,xrx300-gswip",
+	"lantiq,xrx330-gswip",
+#endif
+#if IS_ENABLED(CONFIG_NET_DSA_MV88E6060)
+	"marvell,mv88e6060",
+#endif
+#if IS_ENABLED(CONFIG_NET_DSA_MV88E6XXX)
+	"marvell,mv88e6085",
+	"marvell,mv88e6190",
+	"marvell,mv88e6250",
+#endif
+#if IS_ENABLED(CONFIG_NET_DSA_MICROCHIP_KSZ_COMMON)
+	"microchip,ksz8765",
+	"microchip,ksz8794",
+	"microchip,ksz8795",
+	"microchip,ksz8863",
+	"microchip,ksz8873",
+	"microchip,ksz9477",
+	"microchip,ksz9897",
+	"microchip,ksz9893",
+	"microchip,ksz9563",
+	"microchip,ksz8563",
+	"microchip,ksz9567",
+#endif
+#if IS_ENABLED(CONFIG_NET_DSA_SMSC_LAN9303_MDIO)
+	"smsc,lan9303-mdio",
+#endif
+#if IS_ENABLED(CONFIG_NET_DSA_SMSC_LAN9303_I2C)
+	"smsc,lan9303-i2c",
+#endif
+	NULL,
+};
+
+static void dsa_shared_port_validate_of(struct dsa_port *dp,
+					bool *missing_phy_mode,
+					bool *missing_link_description)
+{
+	struct device_node *dn = dp->dn, *phy_np;
+	struct dsa_switch *ds = dp->ds;
+	phy_interface_t mode;
+
+	*missing_phy_mode = false;
+	*missing_link_description = false;
+
+	if (of_get_phy_mode(dn, &mode)) {
+		*missing_phy_mode = true;
+		dev_err(ds->dev,
+			"OF node %pOF of %s port %d lacks the required \"phy-mode\" property\n",
+			dn, dsa_port_is_cpu(dp) ? "CPU" : "DSA", dp->index);
+	}
+
+	/* Note: of_phy_is_fixed_link() also returns true for
+	 * managed = "in-band-status"
+	 */
+	if (of_phy_is_fixed_link(dn))
+		return;
+
+	phy_np = of_parse_phandle(dn, "phy-handle", 0);
+	if (phy_np) {
+		of_node_put(phy_np);
+		return;
+	}
+
+	*missing_link_description = true;
+
+	dev_err(ds->dev,
+		"OF node %pOF of %s port %d lacks the required \"phy-handle\", \"fixed-link\" or \"managed\" properties\n",
+		dn, dsa_port_is_cpu(dp) ? "CPU" : "DSA", dp->index);
+}
+
 int dsa_shared_port_link_register_of(struct dsa_port *dp)
 {
 	struct dsa_switch *ds = dp->ds;
-	struct device_node *phy_np;
+	bool missing_link_description;
+	bool missing_phy_mode;
 	int port = dp->index;
 
+	dsa_shared_port_validate_of(dp, &missing_phy_mode,
+				    &missing_link_description);
+
+	if ((missing_phy_mode || missing_link_description) &&
+	    !of_device_compatible_match(ds->dev->of_node,
+					dsa_switches_apply_workarounds))
+		return -EINVAL;
+
 	if (!ds->ops->adjust_link) {
-		phy_np = of_parse_phandle(dp->dn, "phy-handle", 0);
-		if (of_phy_is_fixed_link(dp->dn) || phy_np) {
+		if (missing_link_description) {
+			dev_warn(ds->dev,
+				 "Skipping phylink registration for %s port %d\n",
+				 dsa_port_is_cpu(dp) ? "CPU" : "DSA", dp->index);
+		} else {
 			if (ds->ops->phylink_mac_link_down)
 				ds->ops->phylink_mac_link_down(ds, port,
 					MLO_AN_FIXED, PHY_INTERFACE_MODE_NA);
-			of_node_put(phy_np);
+
 			return dsa_shared_port_phylink_register(dp);
 		}
-		of_node_put(phy_np);
 		return 0;
 	}