diff --git a/drivers/net/dsa/mv88e6xxx/Makefile b/drivers/net/dsa/mv88e6xxx/Makefile
index e85755dde90b..aa645ff86f64 100644
--- a/drivers/net/dsa/mv88e6xxx/Makefile
+++ b/drivers/net/dsa/mv88e6xxx/Makefile
@@ -10,6 +10,7 @@ mv88e6xxx-$(CONFIG_NET_DSA_MV88E6XXX_GLOBAL2) += global2_scratch.o
 mv88e6xxx-$(CONFIG_NET_DSA_MV88E6XXX_PTP) += hwtstamp.o
 mv88e6xxx-objs += phy.o
 mv88e6xxx-objs += port.o
+mv88e6xxx-objs += port_hidden.o
 mv88e6xxx-$(CONFIG_NET_DSA_MV88E6XXX_PTP) += ptp.o
 mv88e6xxx-objs += serdes.o
 mv88e6xxx-objs += smi.o
diff --git a/drivers/net/dsa/mv88e6xxx/chip.c b/drivers/net/dsa/mv88e6xxx/chip.c
index d0bf98c10b2b..ec4274d71145 100644
--- a/drivers/net/dsa/mv88e6xxx/chip.c
+++ b/drivers/net/dsa/mv88e6xxx/chip.c
@@ -2317,60 +2317,6 @@ static int mv88e6xxx_stats_setup(struct mv88e6xxx_chip *chip)
 	return mv88e6xxx_g1_stats_clear(chip);
 }
 
-/* The mv88e6390 has some hidden registers used for debug and
- * development. The errata also makes use of them.
- */
-static int mv88e6390_hidden_write(struct mv88e6xxx_chip *chip, int port,
-				  int reg, u16 val)
-{
-	u16 ctrl;
-	int err;
-
-	err = mv88e6xxx_port_write(chip, PORT_RESERVED_1A_DATA_PORT,
-				   PORT_RESERVED_1A, val);
-	if (err)
-		return err;
-
-	ctrl = PORT_RESERVED_1A_BUSY | PORT_RESERVED_1A_WRITE |
-	       PORT_RESERVED_1A_BLOCK | port << PORT_RESERVED_1A_PORT_SHIFT |
-	       reg;
-
-	return mv88e6xxx_port_write(chip, PORT_RESERVED_1A_CTRL_PORT,
-				    PORT_RESERVED_1A, ctrl);
-}
-
-static int mv88e6390_hidden_wait(struct mv88e6xxx_chip *chip)
-{
-	int bit = __bf_shf(PORT_RESERVED_1A_BUSY);
-
-	return mv88e6xxx_wait_bit(chip, PORT_RESERVED_1A_CTRL_PORT,
-				  PORT_RESERVED_1A, bit, 0);
-}
-
-
-static int mv88e6390_hidden_read(struct mv88e6xxx_chip *chip, int port,
-				  int reg, u16 *val)
-{
-	u16 ctrl;
-	int err;
-
-	ctrl = PORT_RESERVED_1A_BUSY | PORT_RESERVED_1A_READ |
-	       PORT_RESERVED_1A_BLOCK | port << PORT_RESERVED_1A_PORT_SHIFT |
-	       reg;
-
-	err = mv88e6xxx_port_write(chip, PORT_RESERVED_1A_CTRL_PORT,
-				   PORT_RESERVED_1A, ctrl);
-	if (err)
-		return err;
-
-	err = mv88e6390_hidden_wait(chip);
-	if (err)
-		return err;
-
-	return 	mv88e6xxx_port_read(chip, PORT_RESERVED_1A_DATA_PORT,
-				    PORT_RESERVED_1A, val);
-}
-
 /* Check if the errata has already been applied. */
 static bool mv88e6390_setup_errata_applied(struct mv88e6xxx_chip *chip)
 {
@@ -2379,7 +2325,7 @@ static bool mv88e6390_setup_errata_applied(struct mv88e6xxx_chip *chip)
 	u16 val;
 
 	for (port = 0; port < mv88e6xxx_num_ports(chip); port++) {
-		err = mv88e6390_hidden_read(chip, port, 0, &val);
+		err = mv88e6xxx_port_hidden_read(chip, 0xf, port, 0, &val);
 		if (err) {
 			dev_err(chip->dev,
 				"Error reading hidden register: %d\n", err);
@@ -2412,7 +2358,7 @@ static int mv88e6390_setup_errata(struct mv88e6xxx_chip *chip)
 	}
 
 	for (port = 0; port < mv88e6xxx_num_ports(chip); port++) {
-		err = mv88e6390_hidden_write(chip, port, 0, 0x01c0);
+		err = mv88e6xxx_port_hidden_write(chip, 0xf, port, 0, 0x01c0);
 		if (err)
 			return err;
 	}
diff --git a/drivers/net/dsa/mv88e6xxx/port.h b/drivers/net/dsa/mv88e6xxx/port.h
index 1abf5ea033e2..21d2d8f7c8f9 100644
--- a/drivers/net/dsa/mv88e6xxx/port.h
+++ b/drivers/net/dsa/mv88e6xxx/port.h
@@ -261,14 +261,14 @@
 #define MV88E6095_PORT_IEEE_PRIO_REMAP_4567	0x19
 
 /* Offset 0x1a: Magic undocumented errata register */
-#define PORT_RESERVED_1A			0x1a
-#define PORT_RESERVED_1A_BUSY			BIT(15)
-#define PORT_RESERVED_1A_WRITE			BIT(14)
-#define PORT_RESERVED_1A_READ			0
-#define PORT_RESERVED_1A_PORT_SHIFT		5
-#define PORT_RESERVED_1A_BLOCK			(0xf << 10)
-#define PORT_RESERVED_1A_CTRL_PORT		4
-#define PORT_RESERVED_1A_DATA_PORT		5
+#define MV88E6XXX_PORT_RESERVED_1A		0x1a
+#define MV88E6XXX_PORT_RESERVED_1A_BUSY		0x8000
+#define MV88E6XXX_PORT_RESERVED_1A_WRITE	0x4000
+#define MV88E6XXX_PORT_RESERVED_1A_READ		0x0000
+#define MV88E6XXX_PORT_RESERVED_1A_PORT_SHIFT	5
+#define MV88E6XXX_PORT_RESERVED_1A_BLOCK_SHIFT	10
+#define MV88E6XXX_PORT_RESERVED_1A_CTRL_PORT	0x04
+#define MV88E6XXX_PORT_RESERVED_1A_DATA_PORT	0x05
 
 int mv88e6xxx_port_read(struct mv88e6xxx_chip *chip, int port, int reg,
 			u16 *val);
@@ -353,4 +353,10 @@ int mv88e6095_port_set_upstream_port(struct mv88e6xxx_chip *chip, int port,
 int mv88e6xxx_port_disable_learn_limit(struct mv88e6xxx_chip *chip, int port);
 int mv88e6xxx_port_disable_pri_override(struct mv88e6xxx_chip *chip, int port);
 
+int mv88e6xxx_port_hidden_write(struct mv88e6xxx_chip *chip, int block,
+				int port, int reg, u16 val);
+int mv88e6xxx_port_hidden_wait(struct mv88e6xxx_chip *chip);
+int mv88e6xxx_port_hidden_read(struct mv88e6xxx_chip *chip, int block, int port,
+			       int reg, u16 *val);
+
 #endif /* _MV88E6XXX_PORT_H */
diff --git a/drivers/net/dsa/mv88e6xxx/port_hidden.c b/drivers/net/dsa/mv88e6xxx/port_hidden.c
new file mode 100644
index 000000000000..b49d05f0e117
--- /dev/null
+++ b/drivers/net/dsa/mv88e6xxx/port_hidden.c
@@ -0,0 +1,70 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Marvell 88E6xxx Switch Hidden Registers support
+ *
+ * Copyright (c) 2008 Marvell Semiconductor
+ *
+ * Copyright (c) 2019 Andrew Lunn <andrew@lunn.ch>
+ */
+
+#include <linux/bitfield.h>
+
+#include "chip.h"
+#include "port.h"
+
+/* The mv88e6390 and mv88e6341 have some hidden registers used for debug and
+ * development. The errata also makes use of them.
+ */
+int mv88e6xxx_port_hidden_write(struct mv88e6xxx_chip *chip, int block,
+				int port, int reg, u16 val)
+{
+	u16 ctrl;
+	int err;
+
+	err = mv88e6xxx_port_write(chip, MV88E6XXX_PORT_RESERVED_1A_DATA_PORT,
+				   MV88E6XXX_PORT_RESERVED_1A, val);
+	if (err)
+		return err;
+
+	ctrl = MV88E6XXX_PORT_RESERVED_1A_BUSY |
+	       MV88E6XXX_PORT_RESERVED_1A_WRITE |
+	       block << MV88E6XXX_PORT_RESERVED_1A_BLOCK_SHIFT |
+	       port << MV88E6XXX_PORT_RESERVED_1A_PORT_SHIFT |
+	       reg;
+
+	return mv88e6xxx_port_write(chip, MV88E6XXX_PORT_RESERVED_1A_CTRL_PORT,
+				    MV88E6XXX_PORT_RESERVED_1A, ctrl);
+}
+
+int mv88e6xxx_port_hidden_wait(struct mv88e6xxx_chip *chip)
+{
+	int bit = __bf_shf(MV88E6XXX_PORT_RESERVED_1A_BUSY);
+
+	return mv88e6xxx_wait_bit(chip, MV88E6XXX_PORT_RESERVED_1A_CTRL_PORT,
+				  MV88E6XXX_PORT_RESERVED_1A, bit, 0);
+}
+
+int mv88e6xxx_port_hidden_read(struct mv88e6xxx_chip *chip, int block, int port,
+			       int reg, u16 *val)
+{
+	u16 ctrl;
+	int err;
+
+	ctrl = MV88E6XXX_PORT_RESERVED_1A_BUSY |
+	       MV88E6XXX_PORT_RESERVED_1A_READ |
+	       block << MV88E6XXX_PORT_RESERVED_1A_BLOCK_SHIFT |
+	       port << MV88E6XXX_PORT_RESERVED_1A_PORT_SHIFT |
+	       reg;
+
+	err = mv88e6xxx_port_write(chip, MV88E6XXX_PORT_RESERVED_1A_CTRL_PORT,
+				   MV88E6XXX_PORT_RESERVED_1A, ctrl);
+	if (err)
+		return err;
+
+	err = mv88e6xxx_port_hidden_wait(chip);
+	if (err)
+		return err;
+
+	return mv88e6xxx_port_read(chip, MV88E6XXX_PORT_RESERVED_1A_DATA_PORT,
+				   MV88E6XXX_PORT_RESERVED_1A, val);
+}