net: mdio: Move MDIO drivers into a new subdirectory

Move all the MDIO drivers and multiplexers into drivers/net/mdio.  The
mdio core is however left in the phy directory, due to mutual
dependencies between the MDIO core and the PHY core.

Take this opportunity to sort the Kconfig based on the menuconfig
strings, and move the multiplexers to the end with a separating
comment.

v2:
Fix typo in commit message

Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>

26 files changed, 5090 insertions, 0 deletions

diff --git a/drivers/net/mdio/Kconfig b/drivers/net/mdio/Kconfig
new file mode 100644
index 000000000000..1299880dfe74
--- /dev/null
+++ b/drivers/net/mdio/Kconfig
@@ -0,0 +1,241 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# MDIO Layer Configuration
+#
+
+menuconfig MDIO_DEVICE
+	tristate "MDIO bus device drivers"
+	help
+	  MDIO devices and driver infrastructure code.
+
+if MDIO_DEVICE
+
+config MDIO_BUS
+	tristate
+	default m if PHYLIB=m
+	default MDIO_DEVICE
+	help
+	  This internal symbol is used for link time dependencies and it
+	  reflects whether the mdio_bus/mdio_device code is built as a
+	  loadable module or built-in.
+
+if MDIO_BUS
+
+config MDIO_DEVRES
+	tristate
+
+config MDIO_SUN4I
+	tristate "Allwinner sun4i MDIO interface support"
+	depends on ARCH_SUNXI || COMPILE_TEST
+	help
+	  This driver supports the MDIO interface found in the network
+	  interface units of the Allwinner SoC that have an EMAC (A10,
+	  A12, A10s, etc.)
+
+config MDIO_XGENE
+	tristate "APM X-Gene SoC MDIO bus controller"
+	depends on ARCH_XGENE || COMPILE_TEST
+	help
+	  This module provides a driver for the MDIO busses found in the
+	  APM X-Gene SoC's.
+
+config MDIO_ASPEED
+	tristate "ASPEED MDIO bus controller"
+	depends on ARCH_ASPEED || COMPILE_TEST
+	depends on OF_MDIO && HAS_IOMEM
+	help
+	  This module provides a driver for the independent MDIO bus
+	  controllers found in the ASPEED AST2600 SoC. This is a driver for the
+	  third revision of the ASPEED MDIO register interface - the first two
+	  revisions are the "old" and "new" interfaces found in the AST2400 and
+	  AST2500, embedded in the MAC. For legacy reasons, FTGMAC100 driver
+	  continues to drive the embedded MDIO controller for the AST2400 and
+	  AST2500 SoCs, so say N if AST2600 support is not required.
+
+config MDIO_BITBANG
+	tristate "Bitbanged MDIO buses"
+	help
+	  This module implements the MDIO bus protocol in software,
+	  for use by low level drivers that export the ability to
+	  drive the relevant pins.
+
+	  If in doubt, say N.
+
+config MDIO_BCM_IPROC
+	tristate "Broadcom iProc MDIO bus controller"
+	depends on ARCH_BCM_IPROC || COMPILE_TEST
+	depends on HAS_IOMEM && OF_MDIO
+	default ARCH_BCM_IPROC
+	help
+	  This module provides a driver for the MDIO busses found in the
+	  Broadcom iProc SoC's.
+
+config MDIO_BCM_UNIMAC
+	tristate "Broadcom UniMAC MDIO bus controller"
+	depends on HAS_IOMEM
+	help
+	  This module provides a driver for the Broadcom UniMAC MDIO busses.
+	  This hardware can be found in the Broadcom GENET Ethernet MAC
+	  controllers as well as some Broadcom Ethernet switches such as the
+	  Starfighter 2 switches.
+
+config MDIO_CAVIUM
+	tristate
+
+config MDIO_GPIO
+	tristate "GPIO lib-based bitbanged MDIO buses"
+	depends on MDIO_BITBANG
+	depends on GPIOLIB || COMPILE_TEST
+	help
+	  Supports GPIO lib-based MDIO busses.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called mdio-gpio.
+
+config MDIO_HISI_FEMAC
+	tristate "Hisilicon FEMAC MDIO bus controller"
+	depends on HAS_IOMEM && OF_MDIO
+	help
+	  This module provides a driver for the MDIO busses found in the
+	  Hisilicon SoC that have an Fast Ethernet MAC.
+
+config MDIO_I2C
+	tristate
+	depends on I2C
+	help
+	  Support I2C based PHYs.  This provides a MDIO bus bridged
+	  to I2C to allow PHYs connected in I2C mode to be accessed
+	  using the existing infrastructure.
+
+	  This is library mode.
+
+config MDIO_MVUSB
+	tristate "Marvell USB to MDIO Adapter"
+	depends on USB
+	select MDIO_DEVRES
+	help
+	  A USB to MDIO converter present on development boards for
+	  Marvell's Link Street family of Ethernet switches.
+
+config MDIO_MSCC_MIIM
+	tristate "Microsemi MIIM interface support"
+	depends on HAS_IOMEM
+	select MDIO_DEVRES
+	help
+	  This driver supports the MIIM (MDIO) interface found in the network
+	  switches of the Microsemi SoCs; it is recommended to switch on
+	  CONFIG_HIGH_RES_TIMERS
+
+config MDIO_MOXART
+	tristate "MOXA ART MDIO interface support"
+	depends on ARCH_MOXART || COMPILE_TEST
+	help
+	  This driver supports the MDIO interface found in the network
+	  interface units of the MOXA ART SoC
+
+config MDIO_OCTEON
+	tristate "Octeon and some ThunderX SOCs MDIO buses"
+	depends on (64BIT && OF_MDIO) || COMPILE_TEST
+	depends on HAS_IOMEM
+	select MDIO_CAVIUM
+	help
+	  This module provides a driver for the Octeon and ThunderX MDIO
+	  buses. It is required by the Octeon and ThunderX ethernet device
+	  drivers on some systems.
+
+config MDIO_IPQ4019
+	tristate "Qualcomm IPQ4019 MDIO interface support"
+	depends on HAS_IOMEM && OF_MDIO
+	help
+	  This driver supports the MDIO interface found in Qualcomm
+	  IPQ40xx series Soc-s.
+
+config MDIO_IPQ8064
+	tristate "Qualcomm IPQ8064 MDIO interface support"
+	depends on HAS_IOMEM && OF_MDIO
+	depends on MFD_SYSCON
+	help
+	  This driver supports the MDIO interface found in the network
+	  interface units of the IPQ8064 SoC
+
+config MDIO_THUNDER
+	tristate "ThunderX SOCs MDIO buses"
+	depends on 64BIT
+	depends on PCI
+	select MDIO_CAVIUM
+	help
+	  This driver supports the MDIO interfaces found on Cavium
+	  ThunderX SoCs when the MDIO bus device appears as a PCI
+	  device.
+
+comment "MDIO Multiplexers"
+
+config MDIO_BUS_MUX
+	tristate
+	depends on OF_MDIO
+	help
+	  This module provides a driver framework for MDIO bus
+	  multiplexers which connect one of several child MDIO busses
+	  to a parent bus.  Switching between child busses is done by
+	  device specific drivers.
+
+config MDIO_BUS_MUX_MESON_G12A
+	tristate "Amlogic G12a based MDIO bus multiplexer"
+	depends on ARCH_MESON || COMPILE_TEST
+	depends on OF_MDIO && HAS_IOMEM && COMMON_CLK
+	select MDIO_BUS_MUX
+	default m if ARCH_MESON
+	help
+	  This module provides a driver for the MDIO multiplexer/glue of
+	  the amlogic g12a SoC. The multiplexers connects either the external
+	  or the internal MDIO bus to the parent bus.
+
+config MDIO_BUS_MUX_BCM_IPROC
+	tristate "Broadcom iProc based MDIO bus multiplexers"
+	depends on OF && OF_MDIO && (ARCH_BCM_IPROC || COMPILE_TEST)
+	select MDIO_BUS_MUX
+	default ARCH_BCM_IPROC
+	help
+	  This module provides a driver for MDIO bus multiplexers found in
+	  iProc based Broadcom SoCs. This multiplexer connects one of several
+	  child MDIO bus to a parent bus. Buses could be internal as well as
+	  external and selection logic lies inside the same multiplexer.
+
+config MDIO_BUS_MUX_GPIO
+	tristate "GPIO controlled MDIO bus multiplexers"
+	depends on OF_GPIO && OF_MDIO
+	select MDIO_BUS_MUX
+	help
+	  This module provides a driver for MDIO bus multiplexers that
+	  are controlled via GPIO lines.  The multiplexer connects one of
+	  several child MDIO busses to a parent bus.  Child bus
+	  selection is under the control of GPIO lines.
+
+config MDIO_BUS_MUX_MULTIPLEXER
+	tristate "MDIO bus multiplexer using kernel multiplexer subsystem"
+	depends on OF_MDIO
+	select MULTIPLEXER
+	select MDIO_BUS_MUX
+	help
+	  This module provides a driver for MDIO bus multiplexer
+	  that is controlled via the kernel multiplexer subsystem. The
+	  bus multiplexer connects one of several child MDIO busses to
+	  a parent bus.  Child bus selection is under the control of
+	  the kernel multiplexer subsystem.
+
+config MDIO_BUS_MUX_MMIOREG
+	tristate "MMIO device-controlled MDIO bus multiplexers"
+	depends on OF_MDIO && HAS_IOMEM
+	select MDIO_BUS_MUX
+	help
+	  This module provides a driver for MDIO bus multiplexers that
+	  are controlled via a simple memory-mapped device, like an FPGA.
+	  The multiplexer connects one of several child MDIO busses to a
+	  parent bus.  Child bus selection is under the control of one of
+	  the FPGA's registers.
+
+	  Currently, only 8/16/32 bits registers are supported.
+
+
+endif
+endif
diff --git a/drivers/net/mdio/Makefile b/drivers/net/mdio/Makefile
new file mode 100644
index 000000000000..14d1beb633c9
--- /dev/null
+++ b/drivers/net/mdio/Makefile
@@ -0,0 +1,27 @@
+# SPDX-License-Identifier: GPL-2.0
+# Makefile for Linux MDIO bus drivers
+
+obj-$(CONFIG_MDIO_ASPEED)		+= mdio-aspeed.o
+obj-$(CONFIG_MDIO_BCM_IPROC)		+= mdio-bcm-iproc.o
+obj-$(CONFIG_MDIO_BCM_UNIMAC)		+= mdio-bcm-unimac.o
+obj-$(CONFIG_MDIO_BITBANG)		+= mdio-bitbang.o
+obj-$(CONFIG_MDIO_CAVIUM)		+= mdio-cavium.o
+obj-$(CONFIG_MDIO_GPIO)			+= mdio-gpio.o
+obj-$(CONFIG_MDIO_HISI_FEMAC)		+= mdio-hisi-femac.o
+obj-$(CONFIG_MDIO_I2C)			+= mdio-i2c.o
+obj-$(CONFIG_MDIO_IPQ4019)		+= mdio-ipq4019.o
+obj-$(CONFIG_MDIO_IPQ8064)		+= mdio-ipq8064.o
+obj-$(CONFIG_MDIO_MOXART)		+= mdio-moxart.o
+obj-$(CONFIG_MDIO_MSCC_MIIM)		+= mdio-mscc-miim.o
+obj-$(CONFIG_MDIO_MVUSB)		+= mdio-mvusb.o
+obj-$(CONFIG_MDIO_OCTEON)		+= mdio-octeon.o
+obj-$(CONFIG_MDIO_SUN4I)		+= mdio-sun4i.o
+obj-$(CONFIG_MDIO_THUNDER)		+= mdio-thunder.o
+obj-$(CONFIG_MDIO_XGENE)		+= mdio-xgene.o
+
+obj-$(CONFIG_MDIO_BUS_MUX)		+= mdio-mux.o
+obj-$(CONFIG_MDIO_BUS_MUX_BCM_IPROC)	+= mdio-mux-bcm-iproc.o
+obj-$(CONFIG_MDIO_BUS_MUX_GPIO)		+= mdio-mux-gpio.o
+obj-$(CONFIG_MDIO_BUS_MUX_MESON_G12A)	+= mdio-mux-meson-g12a.o
+obj-$(CONFIG_MDIO_BUS_MUX_MMIOREG) 	+= mdio-mux-mmioreg.o
+obj-$(CONFIG_MDIO_BUS_MUX_MULTIPLEXER) 	+= mdio-mux-multiplexer.o
diff --git a/drivers/net/mdio/mdio-aspeed.c b/drivers/net/mdio/mdio-aspeed.c
new file mode 100644
index 000000000000..cad820568f75
--- /dev/null
+++ b/drivers/net/mdio/mdio-aspeed.c
@@ -0,0 +1,157 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/* Copyright (C) 2019 IBM Corp. */
+
+#include <linux/bitfield.h>
+#include <linux/delay.h>
+#include <linux/iopoll.h>
+#include <linux/mdio.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_mdio.h>
+#include <linux/phy.h>
+#include <linux/platform_device.h>
+
+#define DRV_NAME "mdio-aspeed"
+
+#define ASPEED_MDIO_CTRL		0x0
+#define   ASPEED_MDIO_CTRL_FIRE		BIT(31)
+#define   ASPEED_MDIO_CTRL_ST		BIT(28)
+#define     ASPEED_MDIO_CTRL_ST_C45	0
+#define     ASPEED_MDIO_CTRL_ST_C22	1
+#define   ASPEED_MDIO_CTRL_OP		GENMASK(27, 26)
+#define     MDIO_C22_OP_WRITE		0b01
+#define     MDIO_C22_OP_READ		0b10
+#define   ASPEED_MDIO_CTRL_PHYAD	GENMASK(25, 21)
+#define   ASPEED_MDIO_CTRL_REGAD	GENMASK(20, 16)
+#define   ASPEED_MDIO_CTRL_MIIWDATA	GENMASK(15, 0)
+
+#define ASPEED_MDIO_DATA		0x4
+#define   ASPEED_MDIO_DATA_MDC_THRES	GENMASK(31, 24)
+#define   ASPEED_MDIO_DATA_MDIO_EDGE	BIT(23)
+#define   ASPEED_MDIO_DATA_MDIO_LATCH	GENMASK(22, 20)
+#define   ASPEED_MDIO_DATA_IDLE		BIT(16)
+#define   ASPEED_MDIO_DATA_MIIRDATA	GENMASK(15, 0)
+
+#define ASPEED_MDIO_INTERVAL_US		100
+#define ASPEED_MDIO_TIMEOUT_US		(ASPEED_MDIO_INTERVAL_US * 10)
+
+struct aspeed_mdio {
+	void __iomem *base;
+};
+
+static int aspeed_mdio_read(struct mii_bus *bus, int addr, int regnum)
+{
+	struct aspeed_mdio *ctx = bus->priv;
+	u32 ctrl;
+	u32 data;
+	int rc;
+
+	dev_dbg(&bus->dev, "%s: addr: %d, regnum: %d\n", __func__, addr,
+		regnum);
+
+	/* Just clause 22 for the moment */
+	if (regnum & MII_ADDR_C45)
+		return -EOPNOTSUPP;
+
+	ctrl = ASPEED_MDIO_CTRL_FIRE
+		| FIELD_PREP(ASPEED_MDIO_CTRL_ST, ASPEED_MDIO_CTRL_ST_C22)
+		| FIELD_PREP(ASPEED_MDIO_CTRL_OP, MDIO_C22_OP_READ)
+		| FIELD_PREP(ASPEED_MDIO_CTRL_PHYAD, addr)
+		| FIELD_PREP(ASPEED_MDIO_CTRL_REGAD, regnum);
+
+	iowrite32(ctrl, ctx->base + ASPEED_MDIO_CTRL);
+
+	rc = readl_poll_timeout(ctx->base + ASPEED_MDIO_DATA, data,
+				data & ASPEED_MDIO_DATA_IDLE,
+				ASPEED_MDIO_INTERVAL_US,
+				ASPEED_MDIO_TIMEOUT_US);
+	if (rc < 0)
+		return rc;
+
+	return FIELD_GET(ASPEED_MDIO_DATA_MIIRDATA, data);
+}
+
+static int aspeed_mdio_write(struct mii_bus *bus, int addr, int regnum, u16 val)
+{
+	struct aspeed_mdio *ctx = bus->priv;
+	u32 ctrl;
+
+	dev_dbg(&bus->dev, "%s: addr: %d, regnum: %d, val: 0x%x\n",
+		__func__, addr, regnum, val);
+
+	/* Just clause 22 for the moment */
+	if (regnum & MII_ADDR_C45)
+		return -EOPNOTSUPP;
+
+	ctrl = ASPEED_MDIO_CTRL_FIRE
+		| FIELD_PREP(ASPEED_MDIO_CTRL_ST, ASPEED_MDIO_CTRL_ST_C22)
+		| FIELD_PREP(ASPEED_MDIO_CTRL_OP, MDIO_C22_OP_WRITE)
+		| FIELD_PREP(ASPEED_MDIO_CTRL_PHYAD, addr)
+		| FIELD_PREP(ASPEED_MDIO_CTRL_REGAD, regnum)
+		| FIELD_PREP(ASPEED_MDIO_CTRL_MIIWDATA, val);
+
+	iowrite32(ctrl, ctx->base + ASPEED_MDIO_CTRL);
+
+	return readl_poll_timeout(ctx->base + ASPEED_MDIO_CTRL, ctrl,
+				  !(ctrl & ASPEED_MDIO_CTRL_FIRE),
+				  ASPEED_MDIO_INTERVAL_US,
+				  ASPEED_MDIO_TIMEOUT_US);
+}
+
+static int aspeed_mdio_probe(struct platform_device *pdev)
+{
+	struct aspeed_mdio *ctx;
+	struct mii_bus *bus;
+	int rc;
+
+	bus = devm_mdiobus_alloc_size(&pdev->dev, sizeof(*ctx));
+	if (!bus)
+		return -ENOMEM;
+
+	ctx = bus->priv;
+	ctx->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(ctx->base))
+		return PTR_ERR(ctx->base);
+
+	bus->name = DRV_NAME;
+	snprintf(bus->id, MII_BUS_ID_SIZE, "%s%d", pdev->name, pdev->id);
+	bus->parent = &pdev->dev;
+	bus->read = aspeed_mdio_read;
+	bus->write = aspeed_mdio_write;
+
+	rc = of_mdiobus_register(bus, pdev->dev.of_node);
+	if (rc) {
+		dev_err(&pdev->dev, "Cannot register MDIO bus!\n");
+		return rc;
+	}
+
+	platform_set_drvdata(pdev, bus);
+
+	return 0;
+}
+
+static int aspeed_mdio_remove(struct platform_device *pdev)
+{
+	mdiobus_unregister(platform_get_drvdata(pdev));
+
+	return 0;
+}
+
+static const struct of_device_id aspeed_mdio_of_match[] = {
+	{ .compatible = "aspeed,ast2600-mdio", },
+	{ },
+};
+
+static struct platform_driver aspeed_mdio_driver = {
+	.driver = {
+		.name = DRV_NAME,
+		.of_match_table = aspeed_mdio_of_match,
+	},
+	.probe = aspeed_mdio_probe,
+	.remove = aspeed_mdio_remove,
+};
+
+module_platform_driver(aspeed_mdio_driver);
+
+MODULE_AUTHOR("Andrew Jeffery <andrew@aj.id.au>");
+MODULE_LICENSE("GPL");
diff --git a/drivers/net/mdio/mdio-bcm-iproc.c b/drivers/net/mdio/mdio-bcm-iproc.c
new file mode 100644
index 000000000000..77fc970cdfde
--- /dev/null
+++ b/drivers/net/mdio/mdio-bcm-iproc.c
@@ -0,0 +1,221 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2015 Broadcom Corporation
+ */
+
+#include <linux/delay.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/of_mdio.h>
+#include <linux/phy.h>
+#include <linux/platform_device.h>
+#include <linux/sched.h>
+
+#define IPROC_GPHY_MDCDIV    0x1a
+
+#define MII_CTRL_OFFSET      0x000
+
+#define MII_CTRL_DIV_SHIFT   0
+#define MII_CTRL_PRE_SHIFT   7
+#define MII_CTRL_BUSY_SHIFT  8
+
+#define MII_DATA_OFFSET      0x004
+#define MII_DATA_MASK        0xffff
+#define MII_DATA_TA_SHIFT    16
+#define MII_DATA_TA_VAL      2
+#define MII_DATA_RA_SHIFT    18
+#define MII_DATA_PA_SHIFT    23
+#define MII_DATA_OP_SHIFT    28
+#define MII_DATA_OP_WRITE    1
+#define MII_DATA_OP_READ     2
+#define MII_DATA_SB_SHIFT    30
+
+struct iproc_mdio_priv {
+	struct mii_bus *mii_bus;
+	void __iomem *base;
+};
+
+static inline int iproc_mdio_wait_for_idle(void __iomem *base)
+{
+	u32 val;
+	unsigned int timeout = 1000; /* loop for 1s */
+
+	do {
+		val = readl(base + MII_CTRL_OFFSET);
+		if ((val & BIT(MII_CTRL_BUSY_SHIFT)) == 0)
+			return 0;
+
+		usleep_range(1000, 2000);
+	} while (timeout--);
+
+	return -ETIMEDOUT;
+}
+
+static inline void iproc_mdio_config_clk(void __iomem *base)
+{
+	u32 val;
+
+	val = (IPROC_GPHY_MDCDIV << MII_CTRL_DIV_SHIFT) |
+		  BIT(MII_CTRL_PRE_SHIFT);
+	writel(val, base + MII_CTRL_OFFSET);
+}
+
+static int iproc_mdio_read(struct mii_bus *bus, int phy_id, int reg)
+{
+	struct iproc_mdio_priv *priv = bus->priv;
+	u32 cmd;
+	int rc;
+
+	rc = iproc_mdio_wait_for_idle(priv->base);
+	if (rc)
+		return rc;
+
+	/* Prepare the read operation */
+	cmd = (MII_DATA_TA_VAL << MII_DATA_TA_SHIFT) |
+		(reg << MII_DATA_RA_SHIFT) |
+		(phy_id << MII_DATA_PA_SHIFT) |
+		BIT(MII_DATA_SB_SHIFT) |
+		(MII_DATA_OP_READ << MII_DATA_OP_SHIFT);
+
+	writel(cmd, priv->base + MII_DATA_OFFSET);
+
+	rc = iproc_mdio_wait_for_idle(priv->base);
+	if (rc)
+		return rc;
+
+	cmd = readl(priv->base + MII_DATA_OFFSET) & MII_DATA_MASK;
+
+	return cmd;
+}
+
+static int iproc_mdio_write(struct mii_bus *bus, int phy_id,
+			    int reg, u16 val)
+{
+	struct iproc_mdio_priv *priv = bus->priv;
+	u32 cmd;
+	int rc;
+
+	rc = iproc_mdio_wait_for_idle(priv->base);
+	if (rc)
+		return rc;
+
+	/* Prepare the write operation */
+	cmd = (MII_DATA_TA_VAL << MII_DATA_TA_SHIFT) |
+		(reg << MII_DATA_RA_SHIFT) |
+		(phy_id << MII_DATA_PA_SHIFT) |
+		BIT(MII_DATA_SB_SHIFT) |
+		(MII_DATA_OP_WRITE << MII_DATA_OP_SHIFT) |
+		((u32)(val) & MII_DATA_MASK);
+
+	writel(cmd, priv->base + MII_DATA_OFFSET);
+
+	rc = iproc_mdio_wait_for_idle(priv->base);
+	if (rc)
+		return rc;
+
+	return 0;
+}
+
+static int iproc_mdio_probe(struct platform_device *pdev)
+{
+	struct iproc_mdio_priv *priv;
+	struct mii_bus *bus;
+	int rc;
+
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	priv->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(priv->base)) {
+		dev_err(&pdev->dev, "failed to ioremap register\n");
+		return PTR_ERR(priv->base);
+	}
+
+	priv->mii_bus = mdiobus_alloc();
+	if (!priv->mii_bus) {
+		dev_err(&pdev->dev, "MDIO bus alloc failed\n");
+		return -ENOMEM;
+	}
+
+	bus = priv->mii_bus;
+	bus->priv = priv;
+	bus->name = "iProc MDIO bus";
+	snprintf(bus->id, MII_BUS_ID_SIZE, "%s-%d", pdev->name, pdev->id);
+	bus->parent = &pdev->dev;
+	bus->read = iproc_mdio_read;
+	bus->write = iproc_mdio_write;
+
+	iproc_mdio_config_clk(priv->base);
+
+	rc = of_mdiobus_register(bus, pdev->dev.of_node);
+	if (rc) {
+		dev_err(&pdev->dev, "MDIO bus registration failed\n");
+		goto err_iproc_mdio;
+	}
+
+	platform_set_drvdata(pdev, priv);
+
+	dev_info(&pdev->dev, "Broadcom iProc MDIO bus registered\n");
+
+	return 0;
+
+err_iproc_mdio:
+	mdiobus_free(bus);
+	return rc;
+}
+
+static int iproc_mdio_remove(struct platform_device *pdev)
+{
+	struct iproc_mdio_priv *priv = platform_get_drvdata(pdev);
+
+	mdiobus_unregister(priv->mii_bus);
+	mdiobus_free(priv->mii_bus);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int iproc_mdio_resume(struct device *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+	struct iproc_mdio_priv *priv = platform_get_drvdata(pdev);
+
+	/* restore the mii clock configuration */
+	iproc_mdio_config_clk(priv->base);
+
+	return 0;
+}
+
+static const struct dev_pm_ops iproc_mdio_pm_ops = {
+	.resume = iproc_mdio_resume
+};
+#endif /* CONFIG_PM_SLEEP */
+
+static const struct of_device_id iproc_mdio_of_match[] = {
+	{ .compatible = "brcm,iproc-mdio", },
+	{ /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, iproc_mdio_of_match);
+
+static struct platform_driver iproc_mdio_driver = {
+	.driver = {
+		.name = "iproc-mdio",
+		.of_match_table = iproc_mdio_of_match,
+#ifdef CONFIG_PM_SLEEP
+		.pm = &iproc_mdio_pm_ops,
+#endif
+	},
+	.probe = iproc_mdio_probe,
+	.remove = iproc_mdio_remove,
+};
+
+module_platform_driver(iproc_mdio_driver);
+
+MODULE_AUTHOR("Broadcom Corporation");
+MODULE_DESCRIPTION("Broadcom iProc MDIO bus controller");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:iproc-mdio");
diff --git a/drivers/net/mdio/mdio-bcm-unimac.c b/drivers/net/mdio/mdio-bcm-unimac.c
new file mode 100644
index 000000000000..fbd36891ee64
--- /dev/null
+++ b/drivers/net/mdio/mdio-bcm-unimac.c
@@ -0,0 +1,363 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Broadcom UniMAC MDIO bus controller driver
+ *
+ * Copyright (C) 2014-2017 Broadcom
+ */
+
+#include <linux/kernel.h>
+#include <linux/phy.h>
+#include <linux/platform_device.h>
+#include <linux/sched.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+
+#include <linux/of.h>
+#include <linux/of_platform.h>
+#include <linux/of_mdio.h>
+
+#include <linux/platform_data/mdio-bcm-unimac.h>
+
+#define MDIO_CMD		0x00
+#define  MDIO_START_BUSY	(1 << 29)
+#define  MDIO_READ_FAIL		(1 << 28)
+#define  MDIO_RD		(2 << 26)
+#define  MDIO_WR		(1 << 26)
+#define  MDIO_PMD_SHIFT		21
+#define  MDIO_PMD_MASK		0x1F
+#define  MDIO_REG_SHIFT		16
+#define  MDIO_REG_MASK		0x1F
+
+#define MDIO_CFG		0x04
+#define  MDIO_C22		(1 << 0)
+#define  MDIO_C45		0
+#define  MDIO_CLK_DIV_SHIFT	4
+#define  MDIO_CLK_DIV_MASK	0x3F
+#define  MDIO_SUPP_PREAMBLE	(1 << 12)
+
+struct unimac_mdio_priv {
+	struct mii_bus		*mii_bus;
+	void __iomem		*base;
+	int (*wait_func)	(void *wait_func_data);
+	void			*wait_func_data;
+	struct clk		*clk;
+	u32			clk_freq;
+};
+
+static inline u32 unimac_mdio_readl(struct unimac_mdio_priv *priv, u32 offset)
+{
+	/* MIPS chips strapped for BE will automagically configure the
+	 * peripheral registers for CPU-native byte order.
+	 */
+	if (IS_ENABLED(CONFIG_MIPS) && IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
+		return __raw_readl(priv->base + offset);
+	else
+		return readl_relaxed(priv->base + offset);
+}
+
+static inline void unimac_mdio_writel(struct unimac_mdio_priv *priv, u32 val,
+				      u32 offset)
+{
+	if (IS_ENABLED(CONFIG_MIPS) && IS_ENABLED(CONFIG_CPU_BIG_ENDIAN))
+		__raw_writel(val, priv->base + offset);
+	else
+		writel_relaxed(val, priv->base + offset);
+}
+
+static inline void unimac_mdio_start(struct unimac_mdio_priv *priv)
+{
+	u32 reg;
+
+	reg = unimac_mdio_readl(priv, MDIO_CMD);
+	reg |= MDIO_START_BUSY;
+	unimac_mdio_writel(priv, reg, MDIO_CMD);
+}
+
+static inline unsigned int unimac_mdio_busy(struct unimac_mdio_priv *priv)
+{
+	return unimac_mdio_readl(priv, MDIO_CMD) & MDIO_START_BUSY;
+}
+
+static int unimac_mdio_poll(void *wait_func_data)
+{
+	struct unimac_mdio_priv *priv = wait_func_data;
+	unsigned int timeout = 1000;
+
+	do {
+		if (!unimac_mdio_busy(priv))
+			return 0;
+
+		usleep_range(1000, 2000);
+	} while (--timeout);
+
+	return -ETIMEDOUT;
+}
+
+static int unimac_mdio_read(struct mii_bus *bus, int phy_id, int reg)
+{
+	struct unimac_mdio_priv *priv = bus->priv;
+	int ret;
+	u32 cmd;
+
+	/* Prepare the read operation */
+	cmd = MDIO_RD | (phy_id << MDIO_PMD_SHIFT) | (reg << MDIO_REG_SHIFT);
+	unimac_mdio_writel(priv, cmd, MDIO_CMD);
+
+	/* Start MDIO transaction */
+	unimac_mdio_start(priv);
+
+	ret = priv->wait_func(priv->wait_func_data);
+	if (ret)
+		return ret;
+
+	cmd = unimac_mdio_readl(priv, MDIO_CMD);
+
+	/* Some broken devices are known not to release the line during
+	 * turn-around, e.g: Broadcom BCM53125 external switches, so check for
+	 * that condition here and ignore the MDIO controller read failure
+	 * indication.
+	 */
+	if (!(bus->phy_ignore_ta_mask & 1 << phy_id) && (cmd & MDIO_READ_FAIL))
+		return -EIO;
+
+	return cmd & 0xffff;
+}
+
+static int unimac_mdio_write(struct mii_bus *bus, int phy_id,
+			     int reg, u16 val)
+{
+	struct unimac_mdio_priv *priv = bus->priv;
+	u32 cmd;
+
+	/* Prepare the write operation */
+	cmd = MDIO_WR | (phy_id << MDIO_PMD_SHIFT) |
+		(reg << MDIO_REG_SHIFT) | (0xffff & val);
+	unimac_mdio_writel(priv, cmd, MDIO_CMD);
+
+	unimac_mdio_start(priv);
+
+	return priv->wait_func(priv->wait_func_data);
+}
+
+/* Workaround for integrated BCM7xxx Gigabit PHYs which have a problem with
+ * their internal MDIO management controller making them fail to successfully
+ * be read from or written to for the first transaction.  We insert a dummy
+ * BMSR read here to make sure that phy_get_device() and get_phy_id() can
+ * correctly read the PHY MII_PHYSID1/2 registers and successfully register a
+ * PHY device for this peripheral.
+ *
+ * Once the PHY driver is registered, we can workaround subsequent reads from
+ * there (e.g: during system-wide power management).
+ *
+ * bus->reset is invoked before mdiobus_scan during mdiobus_register and is
+ * therefore the right location to stick that workaround. Since we do not want
+ * to read from non-existing PHYs, we either use bus->phy_mask or do a manual
+ * Device Tree scan to limit the search area.
+ */
+static int unimac_mdio_reset(struct mii_bus *bus)
+{
+	struct device_node *np = bus->dev.of_node;
+	struct device_node *child;
+	u32 read_mask = 0;
+	int addr;
+
+	if (!np) {
+		read_mask = ~bus->phy_mask;
+	} else {
+		for_each_available_child_of_node(np, child) {
+			addr = of_mdio_parse_addr(&bus->dev, child);
+			if (addr < 0)
+				continue;
+
+			read_mask |= 1 << addr;
+		}
+	}
+
+	for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
+		if (read_mask & 1 << addr) {
+			dev_dbg(&bus->dev, "Workaround for PHY @ %d\n", addr);
+			mdiobus_read(bus, addr, MII_BMSR);
+		}
+	}
+
+	return 0;
+}
+
+static void unimac_mdio_clk_set(struct unimac_mdio_priv *priv)
+{
+	unsigned long rate;
+	u32 reg, div;
+
+	/* Keep the hardware default values */
+	if (!priv->clk_freq)
+		return;
+
+	if (!priv->clk)
+		rate = 250000000;
+	else
+		rate = clk_get_rate(priv->clk);
+
+	div = (rate / (2 * priv->clk_freq)) - 1;
+	if (div & ~MDIO_CLK_DIV_MASK) {
+		pr_warn("Incorrect MDIO clock frequency, ignoring\n");
+		return;
+	}
+
+	/* The MDIO clock is the reference clock (typicaly 250Mhz) divided by
+	 * 2 x (MDIO_CLK_DIV + 1)
+	 */
+	reg = unimac_mdio_readl(priv, MDIO_CFG);
+	reg &= ~(MDIO_CLK_DIV_MASK << MDIO_CLK_DIV_SHIFT);
+	reg |= div << MDIO_CLK_DIV_SHIFT;
+	unimac_mdio_writel(priv, reg, MDIO_CFG);
+}
+
+static int unimac_mdio_probe(struct platform_device *pdev)
+{
+	struct unimac_mdio_pdata *pdata = pdev->dev.platform_data;
+	struct unimac_mdio_priv *priv;
+	struct device_node *np;
+	struct mii_bus *bus;
+	struct resource *r;
+	int ret;
+
+	np = pdev->dev.of_node;
+
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!r)
+		return -EINVAL;
+
+	/* Just ioremap, as this MDIO block is usually integrated into an
+	 * Ethernet MAC controller register range
+	 */
+	priv->base = devm_ioremap(&pdev->dev, r->start, resource_size(r));
+	if (!priv->base) {
+		dev_err(&pdev->dev, "failed to remap register\n");
+		return -ENOMEM;
+	}
+
+	priv->clk = devm_clk_get_optional(&pdev->dev, NULL);
+	if (IS_ERR(priv->clk))
+		return PTR_ERR(priv->clk);
+
+	ret = clk_prepare_enable(priv->clk);
+	if (ret)
+		return ret;
+
+	if (of_property_read_u32(np, "clock-frequency", &priv->clk_freq))
+		priv->clk_freq = 0;
+
+	unimac_mdio_clk_set(priv);
+
+	priv->mii_bus = mdiobus_alloc();
+	if (!priv->mii_bus) {
+		ret = -ENOMEM;
+		goto out_clk_disable;
+	}
+
+	bus = priv->mii_bus;
+	bus->priv = priv;
+	if (pdata) {
+		bus->name = pdata->bus_name;
+		priv->wait_func = pdata->wait_func;
+		priv->wait_func_data = pdata->wait_func_data;
+		bus->phy_mask = ~pdata->phy_mask;
+	} else {
+		bus->name = "unimac MII bus";
+		priv->wait_func_data = priv;
+		priv->wait_func = unimac_mdio_poll;
+	}
+	bus->parent = &pdev->dev;
+	bus->read = unimac_mdio_read;
+	bus->write = unimac_mdio_write;
+	bus->reset = unimac_mdio_reset;
+	snprintf(bus->id, MII_BUS_ID_SIZE, "%s-%d", pdev->name, pdev->id);
+
+	ret = of_mdiobus_register(bus, np);
+	if (ret) {
+		dev_err(&pdev->dev, "MDIO bus registration failed\n");
+		goto out_mdio_free;
+	}
+
+	platform_set_drvdata(pdev, priv);
+
+	dev_info(&pdev->dev, "Broadcom UniMAC MDIO bus\n");
+
+	return 0;
+
+out_mdio_free:
+	mdiobus_free(bus);
+out_clk_disable:
+	clk_disable_unprepare(priv->clk);
+	return ret;
+}
+
+static int unimac_mdio_remove(struct platform_device *pdev)
+{
+	struct unimac_mdio_priv *priv = platform_get_drvdata(pdev);
+
+	mdiobus_unregister(priv->mii_bus);
+	mdiobus_free(priv->mii_bus);
+	clk_disable_unprepare(priv->clk);
+
+	return 0;
+}
+
+static int __maybe_unused unimac_mdio_suspend(struct device *d)
+{
+	struct unimac_mdio_priv *priv = dev_get_drvdata(d);
+
+	clk_disable_unprepare(priv->clk);
+
+	return 0;
+}
+
+static int __maybe_unused unimac_mdio_resume(struct device *d)
+{
+	struct unimac_mdio_priv *priv = dev_get_drvdata(d);
+	int ret;
+
+	ret = clk_prepare_enable(priv->clk);
+	if (ret)
+		return ret;
+
+	unimac_mdio_clk_set(priv);
+
+	return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(unimac_mdio_pm_ops,
+			 unimac_mdio_suspend, unimac_mdio_resume);
+
+static const struct of_device_id unimac_mdio_ids[] = {
+	{ .compatible = "brcm,genet-mdio-v5", },
+	{ .compatible = "brcm,genet-mdio-v4", },
+	{ .compatible = "brcm,genet-mdio-v3", },
+	{ .compatible = "brcm,genet-mdio-v2", },
+	{ .compatible = "brcm,genet-mdio-v1", },
+	{ .compatible = "brcm,unimac-mdio", },
+	{ /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, unimac_mdio_ids);
+
+static struct platform_driver unimac_mdio_driver = {
+	.driver = {
+		.name = UNIMAC_MDIO_DRV_NAME,
+		.of_match_table = unimac_mdio_ids,
+		.pm = &unimac_mdio_pm_ops,
+	},
+	.probe	= unimac_mdio_probe,
+	.remove	= unimac_mdio_remove,
+};
+module_platform_driver(unimac_mdio_driver);
+
+MODULE_AUTHOR("Broadcom Corporation");
+MODULE_DESCRIPTION("Broadcom UniMAC MDIO bus controller");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" UNIMAC_MDIO_DRV_NAME);
diff --git a/drivers/net/mdio/mdio-bitbang.c b/drivers/net/mdio/mdio-bitbang.c
new file mode 100644
index 000000000000..5136275c8e73
--- /dev/null
+++ b/drivers/net/mdio/mdio-bitbang.c
@@ -0,0 +1,232 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Bitbanged MDIO support.
+ *
+ * Author: Scott Wood <scottwood@freescale.com>
+ * Copyright (c) 2007 Freescale Semiconductor
+ *
+ * Based on CPM2 MDIO code which is:
+ *
+ * Copyright (c) 2003 Intracom S.A.
+ *  by Pantelis Antoniou <panto@intracom.gr>
+ *
+ * 2005 (c) MontaVista Software, Inc.
+ * Vitaly Bordug <vbordug@ru.mvista.com>
+ */
+
+#include <linux/module.h>
+#include <linux/mdio-bitbang.h>
+#include <linux/types.h>
+#include <linux/delay.h>
+
+#define MDIO_READ 2
+#define MDIO_WRITE 1
+
+#define MDIO_C45 (1<<15)
+#define MDIO_C45_ADDR (MDIO_C45 | 0)
+#define MDIO_C45_READ (MDIO_C45 | 3)
+#define MDIO_C45_WRITE (MDIO_C45 | 1)
+
+#define MDIO_SETUP_TIME 10
+#define MDIO_HOLD_TIME 10
+
+/* Minimum MDC period is 400 ns, plus some margin for error.  MDIO_DELAY
+ * is done twice per period.
+ */
+#define MDIO_DELAY 250
+
+/* The PHY may take up to 300 ns to produce data, plus some margin
+ * for error.
+ */
+#define MDIO_READ_DELAY 350
+
+/* MDIO must already be configured as output. */
+static void mdiobb_send_bit(struct mdiobb_ctrl *ctrl, int val)
+{
+	const struct mdiobb_ops *ops = ctrl->ops;
+
+	ops->set_mdio_data(ctrl, val);
+	ndelay(MDIO_DELAY);
+	ops->set_mdc(ctrl, 1);
+	ndelay(MDIO_DELAY);
+	ops->set_mdc(ctrl, 0);
+}
+
+/* MDIO must already be configured as input. */
+static int mdiobb_get_bit(struct mdiobb_ctrl *ctrl)
+{
+	const struct mdiobb_ops *ops = ctrl->ops;
+
+	ndelay(MDIO_DELAY);
+	ops->set_mdc(ctrl, 1);
+	ndelay(MDIO_READ_DELAY);
+	ops->set_mdc(ctrl, 0);
+
+	return ops->get_mdio_data(ctrl);
+}
+
+/* MDIO must already be configured as output. */
+static void mdiobb_send_num(struct mdiobb_ctrl *ctrl, u16 val, int bits)
+{
+	int i;
+
+	for (i = bits - 1; i >= 0; i--)
+		mdiobb_send_bit(ctrl, (val >> i) & 1);
+}
+
+/* MDIO must already be configured as input. */
+static u16 mdiobb_get_num(struct mdiobb_ctrl *ctrl, int bits)
+{
+	int i;
+	u16 ret = 0;
+
+	for (i = bits - 1; i >= 0; i--) {
+		ret <<= 1;
+		ret |= mdiobb_get_bit(ctrl);
+	}
+
+	return ret;
+}
+
+/* Utility to send the preamble, address, and
+ * register (common to read and write).
+ */
+static void mdiobb_cmd(struct mdiobb_ctrl *ctrl, int op, u8 phy, u8 reg)
+{
+	const struct mdiobb_ops *ops = ctrl->ops;
+	int i;
+
+	ops->set_mdio_dir(ctrl, 1);
+
+	/*
+	 * Send a 32 bit preamble ('1's) with an extra '1' bit for good
+	 * measure.  The IEEE spec says this is a PHY optional
+	 * requirement.  The AMD 79C874 requires one after power up and
+	 * one after a MII communications error.  This means that we are
+	 * doing more preambles than we need, but it is safer and will be
+	 * much more robust.
+	 */
+
+	for (i = 0; i < 32; i++)
+		mdiobb_send_bit(ctrl, 1);
+
+	/* send the start bit (01) and the read opcode (10) or write (01).
+	   Clause 45 operation uses 00 for the start and 11, 10 for
+	   read/write */
+	mdiobb_send_bit(ctrl, 0);
+	if (op & MDIO_C45)
+		mdiobb_send_bit(ctrl, 0);
+	else
+		mdiobb_send_bit(ctrl, 1);
+	mdiobb_send_bit(ctrl, (op >> 1) & 1);
+	mdiobb_send_bit(ctrl, (op >> 0) & 1);
+
+	mdiobb_send_num(ctrl, phy, 5);
+	mdiobb_send_num(ctrl, reg, 5);
+}
+
+/* In clause 45 mode all commands are prefixed by MDIO_ADDR to specify the
+   lower 16 bits of the 21 bit address. This transfer is done identically to a
+   MDIO_WRITE except for a different code. To enable clause 45 mode or
+   MII_ADDR_C45 into the address. Theoretically clause 45 and normal devices
+   can exist on the same bus. Normal devices should ignore the MDIO_ADDR
+   phase. */
+static int mdiobb_cmd_addr(struct mdiobb_ctrl *ctrl, int phy, u32 addr)
+{
+	unsigned int dev_addr = (addr >> 16) & 0x1F;
+	unsigned int reg = addr & 0xFFFF;
+	mdiobb_cmd(ctrl, MDIO_C45_ADDR, phy, dev_addr);
+
+	/* send the turnaround (10) */
+	mdiobb_send_bit(ctrl, 1);
+	mdiobb_send_bit(ctrl, 0);
+
+	mdiobb_send_num(ctrl, reg, 16);
+
+	ctrl->ops->set_mdio_dir(ctrl, 0);
+	mdiobb_get_bit(ctrl);
+
+	return dev_addr;
+}
+
+static int mdiobb_read(struct mii_bus *bus, int phy, int reg)
+{
+	struct mdiobb_ctrl *ctrl = bus->priv;
+	int ret, i;
+
+	if (reg & MII_ADDR_C45) {
+		reg = mdiobb_cmd_addr(ctrl, phy, reg);
+		mdiobb_cmd(ctrl, MDIO_C45_READ, phy, reg);
+	} else
+		mdiobb_cmd(ctrl, MDIO_READ, phy, reg);
+
+	ctrl->ops->set_mdio_dir(ctrl, 0);
+
+	/* check the turnaround bit: the PHY should be driving it to zero, if this
+	 * PHY is listed in phy_ignore_ta_mask as having broken TA, skip that
+	 */
+	if (mdiobb_get_bit(ctrl) != 0 &&
+	    !(bus->phy_ignore_ta_mask & (1 << phy))) {
+		/* PHY didn't drive TA low -- flush any bits it
+		 * may be trying to send.
+		 */
+		for (i = 0; i < 32; i++)
+			mdiobb_get_bit(ctrl);
+
+		return 0xffff;
+	}
+
+	ret = mdiobb_get_num(ctrl, 16);
+	mdiobb_get_bit(ctrl);
+	return ret;
+}
+
+static int mdiobb_write(struct mii_bus *bus, int phy, int reg, u16 val)
+{
+	struct mdiobb_ctrl *ctrl = bus->priv;
+
+	if (reg & MII_ADDR_C45) {
+		reg = mdiobb_cmd_addr(ctrl, phy, reg);
+		mdiobb_cmd(ctrl, MDIO_C45_WRITE, phy, reg);
+	} else
+		mdiobb_cmd(ctrl, MDIO_WRITE, phy, reg);
+
+	/* send the turnaround (10) */
+	mdiobb_send_bit(ctrl, 1);
+	mdiobb_send_bit(ctrl, 0);
+
+	mdiobb_send_num(ctrl, val, 16);
+
+	ctrl->ops->set_mdio_dir(ctrl, 0);
+	mdiobb_get_bit(ctrl);
+	return 0;
+}
+
+struct mii_bus *alloc_mdio_bitbang(struct mdiobb_ctrl *ctrl)
+{
+	struct mii_bus *bus;
+
+	bus = mdiobus_alloc();
+	if (!bus)
+		return NULL;
+
+	__module_get(ctrl->ops->owner);
+
+	bus->read = mdiobb_read;
+	bus->write = mdiobb_write;
+	bus->priv = ctrl;
+
+	return bus;
+}
+EXPORT_SYMBOL(alloc_mdio_bitbang);
+
+void free_mdio_bitbang(struct mii_bus *bus)
+{
+	struct mdiobb_ctrl *ctrl = bus->priv;
+
+	module_put(ctrl->ops->owner);
+	mdiobus_free(bus);
+}
+EXPORT_SYMBOL(free_mdio_bitbang);
+
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/net/mdio/mdio-cavium.c b/drivers/net/mdio/mdio-cavium.c
new file mode 100644
index 000000000000..1afd6fc1a351
--- /dev/null
+++ b/drivers/net/mdio/mdio-cavium.c
@@ -0,0 +1,150 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2009-2016 Cavium, Inc.
+ */
+
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/phy.h>
+#include <linux/io.h>
+
+#include "mdio-cavium.h"
+
+static void cavium_mdiobus_set_mode(struct cavium_mdiobus *p,
+				    enum cavium_mdiobus_mode m)
+{
+	union cvmx_smix_clk smi_clk;
+
+	if (m == p->mode)
+		return;
+
+	smi_clk.u64 = oct_mdio_readq(p->register_base + SMI_CLK);
+	smi_clk.s.mode = (m == C45) ? 1 : 0;
+	smi_clk.s.preamble = 1;
+	oct_mdio_writeq(smi_clk.u64, p->register_base + SMI_CLK);
+	p->mode = m;
+}
+
+static int cavium_mdiobus_c45_addr(struct cavium_mdiobus *p,
+				   int phy_id, int regnum)
+{
+	union cvmx_smix_cmd smi_cmd;
+	union cvmx_smix_wr_dat smi_wr;
+	int timeout = 1000;
+
+	cavium_mdiobus_set_mode(p, C45);
+
+	smi_wr.u64 = 0;
+	smi_wr.s.dat = regnum & 0xffff;
+	oct_mdio_writeq(smi_wr.u64, p->register_base + SMI_WR_DAT);
+
+	regnum = (regnum >> 16) & 0x1f;
+
+	smi_cmd.u64 = 0;
+	smi_cmd.s.phy_op = 0; /* MDIO_CLAUSE_45_ADDRESS */
+	smi_cmd.s.phy_adr = phy_id;
+	smi_cmd.s.reg_adr = regnum;
+	oct_mdio_writeq(smi_cmd.u64, p->register_base + SMI_CMD);
+
+	do {
+		/* Wait 1000 clocks so we don't saturate the RSL bus
+		 * doing reads.
+		 */
+		__delay(1000);
+		smi_wr.u64 = oct_mdio_readq(p->register_base + SMI_WR_DAT);
+	} while (smi_wr.s.pending && --timeout);
+
+	if (timeout <= 0)
+		return -EIO;
+	return 0;
+}
+
+int cavium_mdiobus_read(struct mii_bus *bus, int phy_id, int regnum)
+{
+	struct cavium_mdiobus *p = bus->priv;
+	union cvmx_smix_cmd smi_cmd;
+	union cvmx_smix_rd_dat smi_rd;
+	unsigned int op = 1; /* MDIO_CLAUSE_22_READ */
+	int timeout = 1000;
+
+	if (regnum & MII_ADDR_C45) {
+		int r = cavium_mdiobus_c45_addr(p, phy_id, regnum);
+
+		if (r < 0)
+			return r;
+
+		regnum = (regnum >> 16) & 0x1f;
+		op = 3; /* MDIO_CLAUSE_45_READ */
+	} else {
+		cavium_mdiobus_set_mode(p, C22);
+	}
+
+	smi_cmd.u64 = 0;
+	smi_cmd.s.phy_op = op;
+	smi_cmd.s.phy_adr = phy_id;
+	smi_cmd.s.reg_adr = regnum;
+	oct_mdio_writeq(smi_cmd.u64, p->register_base + SMI_CMD);
+
+	do {
+		/* Wait 1000 clocks so we don't saturate the RSL bus
+		 * doing reads.
+		 */
+		__delay(1000);
+		smi_rd.u64 = oct_mdio_readq(p->register_base + SMI_RD_DAT);
+	} while (smi_rd.s.pending && --timeout);
+
+	if (smi_rd.s.val)
+		return smi_rd.s.dat;
+	else
+		return -EIO;
+}
+EXPORT_SYMBOL(cavium_mdiobus_read);
+
+int cavium_mdiobus_write(struct mii_bus *bus, int phy_id, int regnum, u16 val)
+{
+	struct cavium_mdiobus *p = bus->priv;
+	union cvmx_smix_cmd smi_cmd;
+	union cvmx_smix_wr_dat smi_wr;
+	unsigned int op = 0; /* MDIO_CLAUSE_22_WRITE */
+	int timeout = 1000;
+
+	if (regnum & MII_ADDR_C45) {
+		int r = cavium_mdiobus_c45_addr(p, phy_id, regnum);
+
+		if (r < 0)
+			return r;
+
+		regnum = (regnum >> 16) & 0x1f;
+		op = 1; /* MDIO_CLAUSE_45_WRITE */
+	} else {
+		cavium_mdiobus_set_mode(p, C22);
+	}
+
+	smi_wr.u64 = 0;
+	smi_wr.s.dat = val;
+	oct_mdio_writeq(smi_wr.u64, p->register_base + SMI_WR_DAT);
+
+	smi_cmd.u64 = 0;
+	smi_cmd.s.phy_op = op;
+	smi_cmd.s.phy_adr = phy_id;
+	smi_cmd.s.reg_adr = regnum;
+	oct_mdio_writeq(smi_cmd.u64, p->register_base + SMI_CMD);
+
+	do {
+		/* Wait 1000 clocks so we don't saturate the RSL bus
+		 * doing reads.
+		 */
+		__delay(1000);
+		smi_wr.u64 = oct_mdio_readq(p->register_base + SMI_WR_DAT);
+	} while (smi_wr.s.pending && --timeout);
+
+	if (timeout <= 0)
+		return -EIO;
+
+	return 0;
+}
+EXPORT_SYMBOL(cavium_mdiobus_write);
+
+MODULE_DESCRIPTION("Common code for OCTEON and Thunder MDIO bus drivers");
+MODULE_AUTHOR("David Daney");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/net/mdio/mdio-cavium.h b/drivers/net/mdio/mdio-cavium.h
new file mode 100644
index 000000000000..a2245d436f5d
--- /dev/null
+++ b/drivers/net/mdio/mdio-cavium.h
@@ -0,0 +1,118 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2009-2016 Cavium, Inc.
+ */
+
+enum cavium_mdiobus_mode {
+	UNINIT = 0,
+	C22,
+	C45
+};
+
+#define SMI_CMD		0x0
+#define SMI_WR_DAT	0x8
+#define SMI_RD_DAT	0x10
+#define SMI_CLK		0x18
+#define SMI_EN		0x20
+
+#ifdef __BIG_ENDIAN_BITFIELD
+#define OCT_MDIO_BITFIELD_FIELD(field, more)	\
+	field;					\
+	more
+
+#else
+#define OCT_MDIO_BITFIELD_FIELD(field, more)	\
+	more					\
+	field;
+
+#endif
+
+union cvmx_smix_clk {
+	u64 u64;
+	struct cvmx_smix_clk_s {
+	  OCT_MDIO_BITFIELD_FIELD(u64 reserved_25_63:39,
+	  OCT_MDIO_BITFIELD_FIELD(u64 mode:1,
+	  OCT_MDIO_BITFIELD_FIELD(u64 reserved_21_23:3,
+	  OCT_MDIO_BITFIELD_FIELD(u64 sample_hi:5,
+	  OCT_MDIO_BITFIELD_FIELD(u64 sample_mode:1,
+	  OCT_MDIO_BITFIELD_FIELD(u64 reserved_14_14:1,
+	  OCT_MDIO_BITFIELD_FIELD(u64 clk_idle:1,
+	  OCT_MDIO_BITFIELD_FIELD(u64 preamble:1,
+	  OCT_MDIO_BITFIELD_FIELD(u64 sample:4,
+	  OCT_MDIO_BITFIELD_FIELD(u64 phase:8,
+	  ;))))))))))
+	} s;
+};
+
+union cvmx_smix_cmd {
+	u64 u64;
+	struct cvmx_smix_cmd_s {
+	  OCT_MDIO_BITFIELD_FIELD(u64 reserved_18_63:46,
+	  OCT_MDIO_BITFIELD_FIELD(u64 phy_op:2,
+	  OCT_MDIO_BITFIELD_FIELD(u64 reserved_13_15:3,
+	  OCT_MDIO_BITFIELD_FIELD(u64 phy_adr:5,
+	  OCT_MDIO_BITFIELD_FIELD(u64 reserved_5_7:3,
+	  OCT_MDIO_BITFIELD_FIELD(u64 reg_adr:5,
+	  ;))))))
+	} s;
+};
+
+union cvmx_smix_en {
+	u64 u64;
+	struct cvmx_smix_en_s {
+	  OCT_MDIO_BITFIELD_FIELD(u64 reserved_1_63:63,
+	  OCT_MDIO_BITFIELD_FIELD(u64 en:1,
+	  ;))
+	} s;
+};
+
+union cvmx_smix_rd_dat {
+	u64 u64;
+	struct cvmx_smix_rd_dat_s {
+	  OCT_MDIO_BITFIELD_FIELD(u64 reserved_18_63:46,
+	  OCT_MDIO_BITFIELD_FIELD(u64 pending:1,
+	  OCT_MDIO_BITFIELD_FIELD(u64 val:1,
+	  OCT_MDIO_BITFIELD_FIELD(u64 dat:16,
+	  ;))))
+	} s;
+};
+
+union cvmx_smix_wr_dat {
+	u64 u64;
+	struct cvmx_smix_wr_dat_s {
+	  OCT_MDIO_BITFIELD_FIELD(u64 reserved_18_63:46,
+	  OCT_MDIO_BITFIELD_FIELD(u64 pending:1,
+	  OCT_MDIO_BITFIELD_FIELD(u64 val:1,
+	  OCT_MDIO_BITFIELD_FIELD(u64 dat:16,
+	  ;))))
+	} s;
+};
+
+struct cavium_mdiobus {
+	struct mii_bus *mii_bus;
+	void __iomem *register_base;
+	enum cavium_mdiobus_mode mode;
+};
+
+#ifdef CONFIG_CAVIUM_OCTEON_SOC
+
+#include <asm/octeon/octeon.h>
+
+static inline void oct_mdio_writeq(u64 val, void __iomem *addr)
+{
+	cvmx_write_csr((u64 __force)addr, val);
+}
+
+static inline u64 oct_mdio_readq(void __iomem *addr)
+{
+	return cvmx_read_csr((u64 __force)addr);
+}
+#else
+#include <linux/io-64-nonatomic-lo-hi.h>
+
+#define oct_mdio_writeq(val, addr)	writeq(val, addr)
+#define oct_mdio_readq(addr)		readq(addr)
+#endif
+
+int cavium_mdiobus_read(struct mii_bus *bus, int phy_id, int regnum);
+int cavium_mdiobus_write(struct mii_bus *bus, int phy_id, int regnum, u16 val);
diff --git a/drivers/net/mdio/mdio-gpio.c b/drivers/net/mdio/mdio-gpio.c
new file mode 100644
index 000000000000..1b00235d7dc5
--- /dev/null
+++ b/drivers/net/mdio/mdio-gpio.c
@@ -0,0 +1,217 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * GPIO based MDIO bitbang driver.
+ * Supports OpenFirmware.
+ *
+ * Copyright (c) 2008 CSE Semaphore Belgium.
+ *  by Laurent Pinchart <laurentp@cse-semaphore.com>
+ *
+ * Copyright (C) 2008, Paulius Zaleckas <paulius.zaleckas@teltonika.lt>
+ *
+ * Based on earlier work by
+ *
+ * Copyright (c) 2003 Intracom S.A.
+ *  by Pantelis Antoniou <panto@intracom.gr>
+ *
+ * 2005 (c) MontaVista Software, Inc.
+ * Vitaly Bordug <vbordug@ru.mvista.com>
+ */
+
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/platform_data/mdio-gpio.h>
+#include <linux/mdio-bitbang.h>
+#include <linux/mdio-gpio.h>
+#include <linux/gpio/consumer.h>
+#include <linux/of_mdio.h>
+
+struct mdio_gpio_info {
+	struct mdiobb_ctrl ctrl;
+	struct gpio_desc *mdc, *mdio, *mdo;
+};
+
+static int mdio_gpio_get_data(struct device *dev,
+			      struct mdio_gpio_info *bitbang)
+{
+	bitbang->mdc = devm_gpiod_get_index(dev, NULL, MDIO_GPIO_MDC,
+					    GPIOD_OUT_LOW);
+	if (IS_ERR(bitbang->mdc))
+		return PTR_ERR(bitbang->mdc);
+
+	bitbang->mdio = devm_gpiod_get_index(dev, NULL, MDIO_GPIO_MDIO,
+					     GPIOD_IN);
+	if (IS_ERR(bitbang->mdio))
+		return PTR_ERR(bitbang->mdio);
+
+	bitbang->mdo = devm_gpiod_get_index_optional(dev, NULL, MDIO_GPIO_MDO,
+						     GPIOD_OUT_LOW);
+	return PTR_ERR_OR_ZERO(bitbang->mdo);
+}
+
+static void mdio_dir(struct mdiobb_ctrl *ctrl, int dir)
+{
+	struct mdio_gpio_info *bitbang =
+		container_of(ctrl, struct mdio_gpio_info, ctrl);
+
+	if (bitbang->mdo) {
+		/* Separate output pin. Always set its value to high
+		 * when changing direction. If direction is input,
+		 * assume the pin serves as pull-up. If direction is
+		 * output, the default value is high.
+		 */
+		gpiod_set_value_cansleep(bitbang->mdo, 1);
+		return;
+	}
+
+	if (dir)
+		gpiod_direction_output(bitbang->mdio, 1);
+	else
+		gpiod_direction_input(bitbang->mdio);
+}
+
+static int mdio_get(struct mdiobb_ctrl *ctrl)
+{
+	struct mdio_gpio_info *bitbang =
+		container_of(ctrl, struct mdio_gpio_info, ctrl);
+
+	return gpiod_get_value_cansleep(bitbang->mdio);
+}
+
+static void mdio_set(struct mdiobb_ctrl *ctrl, int what)
+{
+	struct mdio_gpio_info *bitbang =
+		container_of(ctrl, struct mdio_gpio_info, ctrl);
+
+	if (bitbang->mdo)
+		gpiod_set_value_cansleep(bitbang->mdo, what);
+	else
+		gpiod_set_value_cansleep(bitbang->mdio, what);
+}
+
+static void mdc_set(struct mdiobb_ctrl *ctrl, int what)
+{
+	struct mdio_gpio_info *bitbang =
+		container_of(ctrl, struct mdio_gpio_info, ctrl);
+
+	gpiod_set_value_cansleep(bitbang->mdc, what);
+}
+
+static const struct mdiobb_ops mdio_gpio_ops = {
+	.owner = THIS_MODULE,
+	.set_mdc = mdc_set,
+	.set_mdio_dir = mdio_dir,
+	.set_mdio_data = mdio_set,
+	.get_mdio_data = mdio_get,
+};
+
+static struct mii_bus *mdio_gpio_bus_init(struct device *dev,
+					  struct mdio_gpio_info *bitbang,
+					  int bus_id)
+{
+	struct mdio_gpio_platform_data *pdata = dev_get_platdata(dev);
+	struct mii_bus *new_bus;
+
+	bitbang->ctrl.ops = &mdio_gpio_ops;
+
+	new_bus = alloc_mdio_bitbang(&bitbang->ctrl);
+	if (!new_bus)
+		return NULL;
+
+	new_bus->name = "GPIO Bitbanged MDIO";
+	new_bus->parent = dev;
+
+	if (bus_id != -1)
+		snprintf(new_bus->id, MII_BUS_ID_SIZE, "gpio-%x", bus_id);
+	else
+		strncpy(new_bus->id, "gpio", MII_BUS_ID_SIZE);
+
+	if (pdata) {
+		new_bus->phy_mask = pdata->phy_mask;
+		new_bus->phy_ignore_ta_mask = pdata->phy_ignore_ta_mask;
+	}
+
+	dev_set_drvdata(dev, new_bus);
+
+	return new_bus;
+}
+
+static void mdio_gpio_bus_deinit(struct device *dev)
+{
+	struct mii_bus *bus = dev_get_drvdata(dev);
+
+	free_mdio_bitbang(bus);
+}
+
+static void mdio_gpio_bus_destroy(struct device *dev)
+{
+	struct mii_bus *bus = dev_get_drvdata(dev);
+
+	mdiobus_unregister(bus);
+	mdio_gpio_bus_deinit(dev);
+}
+
+static int mdio_gpio_probe(struct platform_device *pdev)
+{
+	struct mdio_gpio_info *bitbang;
+	struct mii_bus *new_bus;
+	int ret, bus_id;
+
+	bitbang = devm_kzalloc(&pdev->dev, sizeof(*bitbang), GFP_KERNEL);
+	if (!bitbang)
+		return -ENOMEM;
+
+	ret = mdio_gpio_get_data(&pdev->dev, bitbang);
+	if (ret)
+		return ret;
+
+	if (pdev->dev.of_node) {
+		bus_id = of_alias_get_id(pdev->dev.of_node, "mdio-gpio");
+		if (bus_id < 0) {
+			dev_warn(&pdev->dev, "failed to get alias id\n");
+			bus_id = 0;
+		}
+	} else {
+		bus_id = pdev->id;
+	}
+
+	new_bus = mdio_gpio_bus_init(&pdev->dev, bitbang, bus_id);
+	if (!new_bus)
+		return -ENODEV;
+
+	ret = of_mdiobus_register(new_bus, pdev->dev.of_node);
+	if (ret)
+		mdio_gpio_bus_deinit(&pdev->dev);
+
+	return ret;
+}
+
+static int mdio_gpio_remove(struct platform_device *pdev)
+{
+	mdio_gpio_bus_destroy(&pdev->dev);
+
+	return 0;
+}
+
+static const struct of_device_id mdio_gpio_of_match[] = {
+	{ .compatible = "virtual,mdio-gpio", },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, mdio_gpio_of_match);
+
+static struct platform_driver mdio_gpio_driver = {
+	.probe = mdio_gpio_probe,
+	.remove = mdio_gpio_remove,
+	.driver		= {
+		.name	= "mdio-gpio",
+		.of_match_table = mdio_gpio_of_match,
+	},
+};
+
+module_platform_driver(mdio_gpio_driver);
+
+MODULE_ALIAS("platform:mdio-gpio");
+MODULE_AUTHOR("Laurent Pinchart, Paulius Zaleckas");
+MODULE_LICENSE("GPL v2");
+MODULE_DESCRIPTION("Generic driver for MDIO bus emulation using GPIO");
diff --git a/drivers/net/mdio/mdio-hisi-femac.c b/drivers/net/mdio/mdio-hisi-femac.c
new file mode 100644
index 000000000000..f231c2fbb1de
--- /dev/null
+++ b/drivers/net/mdio/mdio-hisi-femac.c
@@ -0,0 +1,152 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Hisilicon Fast Ethernet MDIO Bus Driver
+ *
+ * Copyright (c) 2016 HiSilicon Technologies Co., Ltd.
+ */
+
+#include <linux/clk.h>
+#include <linux/iopoll.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_mdio.h>
+#include <linux/platform_device.h>
+
+#define MDIO_RWCTRL		0x00
+#define MDIO_RO_DATA		0x04
+#define MDIO_WRITE		BIT(13)
+#define MDIO_RW_FINISH		BIT(15)
+#define BIT_PHY_ADDR_OFFSET	8
+#define BIT_WR_DATA_OFFSET	16
+
+struct hisi_femac_mdio_data {
+	struct clk *clk;
+	void __iomem *membase;
+};
+
+static int hisi_femac_mdio_wait_ready(struct hisi_femac_mdio_data *data)
+{
+	u32 val;
+
+	return readl_poll_timeout(data->membase + MDIO_RWCTRL,
+				  val, val & MDIO_RW_FINISH, 20, 10000);
+}
+
+static int hisi_femac_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
+{
+	struct hisi_femac_mdio_data *data = bus->priv;
+	int ret;
+
+	ret = hisi_femac_mdio_wait_ready(data);
+	if (ret)
+		return ret;
+
+	writel((mii_id << BIT_PHY_ADDR_OFFSET) | regnum,
+	       data->membase + MDIO_RWCTRL);
+
+	ret = hisi_femac_mdio_wait_ready(data);
+	if (ret)
+		return ret;
+
+	return readl(data->membase + MDIO_RO_DATA) & 0xFFFF;
+}
+
+static int hisi_femac_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
+				 u16 value)
+{
+	struct hisi_femac_mdio_data *data = bus->priv;
+	int ret;
+
+	ret = hisi_femac_mdio_wait_ready(data);
+	if (ret)
+		return ret;
+
+	writel(MDIO_WRITE | (value << BIT_WR_DATA_OFFSET) |
+	       (mii_id << BIT_PHY_ADDR_OFFSET) | regnum,
+	       data->membase + MDIO_RWCTRL);
+
+	return hisi_femac_mdio_wait_ready(data);
+}
+
+static int hisi_femac_mdio_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct mii_bus *bus;
+	struct hisi_femac_mdio_data *data;
+	int ret;
+
+	bus = mdiobus_alloc_size(sizeof(*data));
+	if (!bus)
+		return -ENOMEM;
+
+	bus->name = "hisi_femac_mii_bus";
+	bus->read = &hisi_femac_mdio_read;
+	bus->write = &hisi_femac_mdio_write;
+	snprintf(bus->id, MII_BUS_ID_SIZE, "%s", pdev->name);
+	bus->parent = &pdev->dev;
+
+	data = bus->priv;
+	data->membase = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(data->membase)) {
+		ret = PTR_ERR(data->membase);
+		goto err_out_free_mdiobus;
+	}
+
+	data->clk = devm_clk_get(&pdev->dev, NULL);
+	if (IS_ERR(data->clk)) {
+		ret = PTR_ERR(data->clk);
+		goto err_out_free_mdiobus;
+	}
+
+	ret = clk_prepare_enable(data->clk);
+	if (ret)
+		goto err_out_free_mdiobus;
+
+	ret = of_mdiobus_register(bus, np);
+	if (ret)
+		goto err_out_disable_clk;
+
+	platform_set_drvdata(pdev, bus);
+
+	return 0;
+
+err_out_disable_clk:
+	clk_disable_unprepare(data->clk);
+err_out_free_mdiobus:
+	mdiobus_free(bus);
+	return ret;
+}
+
+static int hisi_femac_mdio_remove(struct platform_device *pdev)
+{
+	struct mii_bus *bus = platform_get_drvdata(pdev);
+	struct hisi_femac_mdio_data *data = bus->priv;
+
+	mdiobus_unregister(bus);
+	clk_disable_unprepare(data->clk);
+	mdiobus_free(bus);
+
+	return 0;
+}
+
+static const struct of_device_id hisi_femac_mdio_dt_ids[] = {
+	{ .compatible = "hisilicon,hisi-femac-mdio" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, hisi_femac_mdio_dt_ids);
+
+static struct platform_driver hisi_femac_mdio_driver = {
+	.probe = hisi_femac_mdio_probe,
+	.remove = hisi_femac_mdio_remove,
+	.driver = {
+		.name = "hisi-femac-mdio",
+		.of_match_table = hisi_femac_mdio_dt_ids,
+	},
+};
+
+module_platform_driver(hisi_femac_mdio_driver);
+
+MODULE_DESCRIPTION("Hisilicon Fast Ethernet MAC MDIO interface driver");
+MODULE_AUTHOR("Dongpo Li <lidongpo@hisilicon.com>");
+MODULE_LICENSE("GPL");
diff --git a/drivers/net/mdio/mdio-i2c.c b/drivers/net/mdio/mdio-i2c.c
new file mode 100644
index 000000000000..09200a70b315
--- /dev/null
+++ b/drivers/net/mdio/mdio-i2c.c
@@ -0,0 +1,117 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * MDIO I2C bridge
+ *
+ * Copyright (C) 2015-2016 Russell King
+ *
+ * Network PHYs can appear on I2C buses when they are part of SFP module.
+ * This driver exposes these PHYs to the networking PHY code, allowing
+ * our PHY drivers access to these PHYs, and so allowing configuration
+ * of their settings.
+ */
+#include <linux/i2c.h>
+#include <linux/mdio/mdio-i2c.h>
+#include <linux/phy.h>
+
+/*
+ * I2C bus addresses 0x50 and 0x51 are normally an EEPROM, which is
+ * specified to be present in SFP modules.  These correspond with PHY
+ * addresses 16 and 17.  Disallow access to these "phy" addresses.
+ */
+static bool i2c_mii_valid_phy_id(int phy_id)
+{
+	return phy_id != 0x10 && phy_id != 0x11;
+}
+
+static unsigned int i2c_mii_phy_addr(int phy_id)
+{
+	return phy_id + 0x40;
+}
+
+static int i2c_mii_read(struct mii_bus *bus, int phy_id, int reg)
+{
+	struct i2c_adapter *i2c = bus->priv;
+	struct i2c_msg msgs[2];
+	u8 addr[3], data[2], *p;
+	int bus_addr, ret;
+
+	if (!i2c_mii_valid_phy_id(phy_id))
+		return 0xffff;
+
+	p = addr;
+	if (reg & MII_ADDR_C45) {
+		*p++ = 0x20 | ((reg >> 16) & 31);
+		*p++ = reg >> 8;
+	}
+	*p++ = reg;
+
+	bus_addr = i2c_mii_phy_addr(phy_id);
+	msgs[0].addr = bus_addr;
+	msgs[0].flags = 0;
+	msgs[0].len = p - addr;
+	msgs[0].buf = addr;
+	msgs[1].addr = bus_addr;
+	msgs[1].flags = I2C_M_RD;
+	msgs[1].len = sizeof(data);
+	msgs[1].buf = data;
+
+	ret = i2c_transfer(i2c, msgs, ARRAY_SIZE(msgs));
+	if (ret != ARRAY_SIZE(msgs))
+		return 0xffff;
+
+	return data[0] << 8 | data[1];
+}
+
+static int i2c_mii_write(struct mii_bus *bus, int phy_id, int reg, u16 val)
+{
+	struct i2c_adapter *i2c = bus->priv;
+	struct i2c_msg msg;
+	int ret;
+	u8 data[5], *p;
+
+	if (!i2c_mii_valid_phy_id(phy_id))
+		return 0;
+
+	p = data;
+	if (reg & MII_ADDR_C45) {
+		*p++ = (reg >> 16) & 31;
+		*p++ = reg >> 8;
+	}
+	*p++ = reg;
+	*p++ = val >> 8;
+	*p++ = val;
+
+	msg.addr = i2c_mii_phy_addr(phy_id);
+	msg.flags = 0;
+	msg.len = p - data;
+	msg.buf = data;
+
+	ret = i2c_transfer(i2c, &msg, 1);
+
+	return ret < 0 ? ret : 0;
+}
+
+struct mii_bus *mdio_i2c_alloc(struct device *parent, struct i2c_adapter *i2c)
+{
+	struct mii_bus *mii;
+
+	if (!i2c_check_functionality(i2c, I2C_FUNC_I2C))
+		return ERR_PTR(-EINVAL);
+
+	mii = mdiobus_alloc();
+	if (!mii)
+		return ERR_PTR(-ENOMEM);
+
+	snprintf(mii->id, MII_BUS_ID_SIZE, "i2c:%s", dev_name(parent));
+	mii->parent = parent;
+	mii->read = i2c_mii_read;
+	mii->write = i2c_mii_write;
+	mii->priv = i2c;
+
+	return mii;
+}
+EXPORT_SYMBOL_GPL(mdio_i2c_alloc);
+
+MODULE_AUTHOR("Russell King");
+MODULE_DESCRIPTION("MDIO I2C bridge library");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/net/mdio/mdio-ipq4019.c b/drivers/net/mdio/mdio-ipq4019.c
new file mode 100644
index 000000000000..1ce81ff2f41d
--- /dev/null
+++ b/drivers/net/mdio/mdio-ipq4019.c
@@ -0,0 +1,160 @@
+// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
+/* Copyright (c) 2015, The Linux Foundation. All rights reserved. */
+/* Copyright (c) 2020 Sartura Ltd. */
+
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/of_address.h>
+#include <linux/of_mdio.h>
+#include <linux/phy.h>
+#include <linux/platform_device.h>
+
+#define MDIO_ADDR_REG				0x44
+#define MDIO_DATA_WRITE_REG			0x48
+#define MDIO_DATA_READ_REG			0x4c
+#define MDIO_CMD_REG				0x50
+#define MDIO_CMD_ACCESS_BUSY		BIT(16)
+#define MDIO_CMD_ACCESS_START		BIT(8)
+#define MDIO_CMD_ACCESS_CODE_READ	0
+#define MDIO_CMD_ACCESS_CODE_WRITE	1
+
+#define ipq4019_MDIO_TIMEOUT	10000
+#define ipq4019_MDIO_SLEEP		10
+
+struct ipq4019_mdio_data {
+	void __iomem	*membase;
+};
+
+static int ipq4019_mdio_wait_busy(struct mii_bus *bus)
+{
+	struct ipq4019_mdio_data *priv = bus->priv;
+	unsigned int busy;
+
+	return readl_poll_timeout(priv->membase + MDIO_CMD_REG, busy,
+				  (busy & MDIO_CMD_ACCESS_BUSY) == 0,
+				  ipq4019_MDIO_SLEEP, ipq4019_MDIO_TIMEOUT);
+}
+
+static int ipq4019_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
+{
+	struct ipq4019_mdio_data *priv = bus->priv;
+	unsigned int cmd;
+
+	/* Reject clause 45 */
+	if (regnum & MII_ADDR_C45)
+		return -EOPNOTSUPP;
+
+	if (ipq4019_mdio_wait_busy(bus))
+		return -ETIMEDOUT;
+
+	/* issue the phy address and reg */
+	writel((mii_id << 8) | regnum, priv->membase + MDIO_ADDR_REG);
+
+	cmd = MDIO_CMD_ACCESS_START | MDIO_CMD_ACCESS_CODE_READ;
+
+	/* issue read command */
+	writel(cmd, priv->membase + MDIO_CMD_REG);
+
+	/* Wait read complete */
+	if (ipq4019_mdio_wait_busy(bus))
+		return -ETIMEDOUT;
+
+	/* Read and return data */
+	return readl(priv->membase + MDIO_DATA_READ_REG);
+}
+
+static int ipq4019_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
+							 u16 value)
+{
+	struct ipq4019_mdio_data *priv = bus->priv;
+	unsigned int cmd;
+
+	/* Reject clause 45 */
+	if (regnum & MII_ADDR_C45)
+		return -EOPNOTSUPP;
+
+	if (ipq4019_mdio_wait_busy(bus))
+		return -ETIMEDOUT;
+
+	/* issue the phy address and reg */
+	writel((mii_id << 8) | regnum, priv->membase + MDIO_ADDR_REG);
+
+	/* issue write data */
+	writel(value, priv->membase + MDIO_DATA_WRITE_REG);
+
+	cmd = MDIO_CMD_ACCESS_START | MDIO_CMD_ACCESS_CODE_WRITE;
+	/* issue write command */
+	writel(cmd, priv->membase + MDIO_CMD_REG);
+
+	/* Wait write complete */
+	if (ipq4019_mdio_wait_busy(bus))
+		return -ETIMEDOUT;
+
+	return 0;
+}
+
+static int ipq4019_mdio_probe(struct platform_device *pdev)
+{
+	struct ipq4019_mdio_data *priv;
+	struct mii_bus *bus;
+	int ret;
+
+	bus = devm_mdiobus_alloc_size(&pdev->dev, sizeof(*priv));
+	if (!bus)
+		return -ENOMEM;
+
+	priv = bus->priv;
+
+	priv->membase = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(priv->membase))
+		return PTR_ERR(priv->membase);
+
+	bus->name = "ipq4019_mdio";
+	bus->read = ipq4019_mdio_read;
+	bus->write = ipq4019_mdio_write;
+	bus->parent = &pdev->dev;
+	snprintf(bus->id, MII_BUS_ID_SIZE, "%s%d", pdev->name, pdev->id);
+
+	ret = of_mdiobus_register(bus, pdev->dev.of_node);
+	if (ret) {
+		dev_err(&pdev->dev, "Cannot register MDIO bus!\n");
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, bus);
+
+	return 0;
+}
+
+static int ipq4019_mdio_remove(struct platform_device *pdev)
+{
+	struct mii_bus *bus = platform_get_drvdata(pdev);
+
+	mdiobus_unregister(bus);
+
+	return 0;
+}
+
+static const struct of_device_id ipq4019_mdio_dt_ids[] = {
+	{ .compatible = "qcom,ipq4019-mdio" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, ipq4019_mdio_dt_ids);
+
+static struct platform_driver ipq4019_mdio_driver = {
+	.probe = ipq4019_mdio_probe,
+	.remove = ipq4019_mdio_remove,
+	.driver = {
+		.name = "ipq4019-mdio",
+		.of_match_table = ipq4019_mdio_dt_ids,
+	},
+};
+
+module_platform_driver(ipq4019_mdio_driver);
+
+MODULE_DESCRIPTION("ipq4019 MDIO interface driver");
+MODULE_AUTHOR("Qualcomm Atheros");
+MODULE_LICENSE("Dual BSD/GPL");
diff --git a/drivers/net/mdio/mdio-ipq8064.c b/drivers/net/mdio/mdio-ipq8064.c
new file mode 100644
index 000000000000..1bd18857e1c5
--- /dev/null
+++ b/drivers/net/mdio/mdio-ipq8064.c
@@ -0,0 +1,166 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Qualcomm IPQ8064 MDIO interface driver
+ *
+ * Copyright (C) 2019 Christian Lamparter <chunkeey@gmail.com>
+ * Copyright (C) 2020 Ansuel Smith <ansuelsmth@gmail.com>
+ */
+
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/regmap.h>
+#include <linux/of_mdio.h>
+#include <linux/phy.h>
+#include <linux/platform_device.h>
+#include <linux/mfd/syscon.h>
+
+/* MII address register definitions */
+#define MII_ADDR_REG_ADDR                       0x10
+#define MII_BUSY                                BIT(0)
+#define MII_WRITE                               BIT(1)
+#define MII_CLKRANGE_60_100M                    (0 << 2)
+#define MII_CLKRANGE_100_150M                   (1 << 2)
+#define MII_CLKRANGE_20_35M                     (2 << 2)
+#define MII_CLKRANGE_35_60M                     (3 << 2)
+#define MII_CLKRANGE_150_250M                   (4 << 2)
+#define MII_CLKRANGE_250_300M                   (5 << 2)
+#define MII_CLKRANGE_MASK			GENMASK(4, 2)
+#define MII_REG_SHIFT				6
+#define MII_REG_MASK				GENMASK(10, 6)
+#define MII_ADDR_SHIFT				11
+#define MII_ADDR_MASK				GENMASK(15, 11)
+
+#define MII_DATA_REG_ADDR                       0x14
+
+#define MII_MDIO_DELAY_USEC                     (1000)
+#define MII_MDIO_RETRY_MSEC                     (10)
+
+struct ipq8064_mdio {
+	struct regmap *base; /* NSS_GMAC0_BASE */
+};
+
+static int
+ipq8064_mdio_wait_busy(struct ipq8064_mdio *priv)
+{
+	u32 busy;
+
+	return regmap_read_poll_timeout(priv->base, MII_ADDR_REG_ADDR, busy,
+					!(busy & MII_BUSY), MII_MDIO_DELAY_USEC,
+					MII_MDIO_RETRY_MSEC * USEC_PER_MSEC);
+}
+
+static int
+ipq8064_mdio_read(struct mii_bus *bus, int phy_addr, int reg_offset)
+{
+	u32 miiaddr = MII_BUSY | MII_CLKRANGE_250_300M;
+	struct ipq8064_mdio *priv = bus->priv;
+	u32 ret_val;
+	int err;
+
+	/* Reject clause 45 */
+	if (reg_offset & MII_ADDR_C45)
+		return -EOPNOTSUPP;
+
+	miiaddr |= ((phy_addr << MII_ADDR_SHIFT) & MII_ADDR_MASK) |
+		   ((reg_offset << MII_REG_SHIFT) & MII_REG_MASK);
+
+	regmap_write(priv->base, MII_ADDR_REG_ADDR, miiaddr);
+	usleep_range(8, 10);
+
+	err = ipq8064_mdio_wait_busy(priv);
+	if (err)
+		return err;
+
+	regmap_read(priv->base, MII_DATA_REG_ADDR, &ret_val);
+	return (int)ret_val;
+}
+
+static int
+ipq8064_mdio_write(struct mii_bus *bus, int phy_addr, int reg_offset, u16 data)
+{
+	u32 miiaddr = MII_WRITE | MII_BUSY | MII_CLKRANGE_250_300M;
+	struct ipq8064_mdio *priv = bus->priv;
+
+	/* Reject clause 45 */
+	if (reg_offset & MII_ADDR_C45)
+		return -EOPNOTSUPP;
+
+	regmap_write(priv->base, MII_DATA_REG_ADDR, data);
+
+	miiaddr |= ((phy_addr << MII_ADDR_SHIFT) & MII_ADDR_MASK) |
+		   ((reg_offset << MII_REG_SHIFT) & MII_REG_MASK);
+
+	regmap_write(priv->base, MII_ADDR_REG_ADDR, miiaddr);
+	usleep_range(8, 10);
+
+	return ipq8064_mdio_wait_busy(priv);
+}
+
+static int
+ipq8064_mdio_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct ipq8064_mdio *priv;
+	struct mii_bus *bus;
+	int ret;
+
+	bus = devm_mdiobus_alloc_size(&pdev->dev, sizeof(*priv));
+	if (!bus)
+		return -ENOMEM;
+
+	bus->name = "ipq8064_mdio_bus";
+	bus->read = ipq8064_mdio_read;
+	bus->write = ipq8064_mdio_write;
+	snprintf(bus->id, MII_BUS_ID_SIZE, "%s-mii", dev_name(&pdev->dev));
+	bus->parent = &pdev->dev;
+
+	priv = bus->priv;
+	priv->base = device_node_to_regmap(np);
+	if (IS_ERR(priv->base)) {
+		if (priv->base == ERR_PTR(-EPROBE_DEFER))
+			return -EPROBE_DEFER;
+
+		dev_err(&pdev->dev, "error getting device regmap, error=%pe\n",
+			priv->base);
+		return PTR_ERR(priv->base);
+	}
+
+	ret = of_mdiobus_register(bus, np);
+	if (ret)
+		return ret;
+
+	platform_set_drvdata(pdev, bus);
+	return 0;
+}
+
+static int
+ipq8064_mdio_remove(struct platform_device *pdev)
+{
+	struct mii_bus *bus = platform_get_drvdata(pdev);
+
+	mdiobus_unregister(bus);
+
+	return 0;
+}
+
+static const struct of_device_id ipq8064_mdio_dt_ids[] = {
+	{ .compatible = "qcom,ipq8064-mdio" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, ipq8064_mdio_dt_ids);
+
+static struct platform_driver ipq8064_mdio_driver = {
+	.probe = ipq8064_mdio_probe,
+	.remove = ipq8064_mdio_remove,
+	.driver = {
+		.name = "ipq8064-mdio",
+		.of_match_table = ipq8064_mdio_dt_ids,
+	},
+};
+
+module_platform_driver(ipq8064_mdio_driver);
+
+MODULE_DESCRIPTION("Qualcomm IPQ8064 MDIO interface driver");
+MODULE_AUTHOR("Christian Lamparter <chunkeey@gmail.com>");
+MODULE_AUTHOR("Ansuel Smith <ansuelsmth@gmail.com>");
+MODULE_LICENSE("GPL");
diff --git a/drivers/net/mdio/mdio-moxart.c b/drivers/net/mdio/mdio-moxart.c
new file mode 100644
index 000000000000..b72c6d185175
--- /dev/null
+++ b/drivers/net/mdio/mdio-moxart.c
@@ -0,0 +1,187 @@
+// SPDX-License-Identifier: GPL-2.0
+/* MOXA ART Ethernet (RTL8201CP) MDIO interface driver
+ *
+ * Copyright (C) 2013 Jonas Jensen <jonas.jensen@gmail.com>
+ */
+
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of_address.h>
+#include <linux/of_mdio.h>
+#include <linux/phy.h>
+#include <linux/platform_device.h>
+
+#define REG_PHY_CTRL            0
+#define REG_PHY_WRITE_DATA      4
+
+/* REG_PHY_CTRL */
+#define MIIWR                   BIT(27) /* init write sequence (auto cleared)*/
+#define MIIRD                   BIT(26)
+#define REGAD_MASK              0x3e00000
+#define PHYAD_MASK              0x1f0000
+#define MIIRDATA_MASK           0xffff
+
+/* REG_PHY_WRITE_DATA */
+#define MIIWDATA_MASK           0xffff
+
+struct moxart_mdio_data {
+	void __iomem		*base;
+};
+
+static int moxart_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
+{
+	struct moxart_mdio_data *data = bus->priv;
+	u32 ctrl = 0;
+	unsigned int count = 5;
+
+	dev_dbg(&bus->dev, "%s\n", __func__);
+
+	ctrl |= MIIRD | ((mii_id << 16) & PHYAD_MASK) |
+		((regnum << 21) & REGAD_MASK);
+
+	writel(ctrl, data->base + REG_PHY_CTRL);
+
+	do {
+		ctrl = readl(data->base + REG_PHY_CTRL);
+
+		if (!(ctrl & MIIRD))
+			return ctrl & MIIRDATA_MASK;
+
+		mdelay(10);
+		count--;
+	} while (count > 0);
+
+	dev_dbg(&bus->dev, "%s timed out\n", __func__);
+
+	return -ETIMEDOUT;
+}
+
+static int moxart_mdio_write(struct mii_bus *bus, int mii_id,
+			     int regnum, u16 value)
+{
+	struct moxart_mdio_data *data = bus->priv;
+	u32 ctrl = 0;
+	unsigned int count = 5;
+
+	dev_dbg(&bus->dev, "%s\n", __func__);
+
+	ctrl |= MIIWR | ((mii_id << 16) & PHYAD_MASK) |
+		((regnum << 21) & REGAD_MASK);
+
+	value &= MIIWDATA_MASK;
+
+	writel(value, data->base + REG_PHY_WRITE_DATA);
+	writel(ctrl, data->base + REG_PHY_CTRL);
+
+	do {
+		ctrl = readl(data->base + REG_PHY_CTRL);
+
+		if (!(ctrl & MIIWR))
+			return 0;
+
+		mdelay(10);
+		count--;
+	} while (count > 0);
+
+	dev_dbg(&bus->dev, "%s timed out\n", __func__);
+
+	return -ETIMEDOUT;
+}
+
+static int moxart_mdio_reset(struct mii_bus *bus)
+{
+	int data, i;
+
+	for (i = 0; i < PHY_MAX_ADDR; i++) {
+		data = moxart_mdio_read(bus, i, MII_BMCR);
+		if (data < 0)
+			continue;
+
+		data |= BMCR_RESET;
+		if (moxart_mdio_write(bus, i, MII_BMCR, data) < 0)
+			continue;
+	}
+
+	return 0;
+}
+
+static int moxart_mdio_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct mii_bus *bus;
+	struct moxart_mdio_data *data;
+	int ret, i;
+
+	bus = mdiobus_alloc_size(sizeof(*data));
+	if (!bus)
+		return -ENOMEM;
+
+	bus->name = "MOXA ART Ethernet MII";
+	bus->read = &moxart_mdio_read;
+	bus->write = &moxart_mdio_write;
+	bus->reset = &moxart_mdio_reset;
+	snprintf(bus->id, MII_BUS_ID_SIZE, "%s-%d-mii", pdev->name, pdev->id);
+	bus->parent = &pdev->dev;
+
+	/* Setting PHY_IGNORE_INTERRUPT here even if it has no effect,
+	 * of_mdiobus_register() sets these PHY_POLL.
+	 * Ideally, the interrupt from MAC controller could be used to
+	 * detect link state changes, not polling, i.e. if there was
+	 * a way phy_driver could set PHY_HAS_INTERRUPT but have that
+	 * interrupt handled in ethernet drivercode.
+	 */
+	for (i = 0; i < PHY_MAX_ADDR; i++)
+		bus->irq[i] = PHY_IGNORE_INTERRUPT;
+
+	data = bus->priv;
+	data->base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(data->base)) {
+		ret = PTR_ERR(data->base);
+		goto err_out_free_mdiobus;
+	}
+
+	ret = of_mdiobus_register(bus, np);
+	if (ret < 0)
+		goto err_out_free_mdiobus;
+
+	platform_set_drvdata(pdev, bus);
+
+	return 0;
+
+err_out_free_mdiobus:
+	mdiobus_free(bus);
+	return ret;
+}
+
+static int moxart_mdio_remove(struct platform_device *pdev)
+{
+	struct mii_bus *bus = platform_get_drvdata(pdev);
+
+	mdiobus_unregister(bus);
+	mdiobus_free(bus);
+
+	return 0;
+}
+
+static const struct of_device_id moxart_mdio_dt_ids[] = {
+	{ .compatible = "moxa,moxart-mdio" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, moxart_mdio_dt_ids);
+
+static struct platform_driver moxart_mdio_driver = {
+	.probe = moxart_mdio_probe,
+	.remove = moxart_mdio_remove,
+	.driver = {
+		.name = "moxart-mdio",
+		.of_match_table = moxart_mdio_dt_ids,
+	},
+};
+
+module_platform_driver(moxart_mdio_driver);
+
+MODULE_DESCRIPTION("MOXA ART MDIO interface driver");
+MODULE_AUTHOR("Jonas Jensen <jonas.jensen@gmail.com>");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/net/mdio/mdio-mscc-miim.c b/drivers/net/mdio/mdio-mscc-miim.c
new file mode 100644
index 000000000000..11f583fd4611
--- /dev/null
+++ b/drivers/net/mdio/mdio-mscc-miim.c
@@ -0,0 +1,212 @@
+// SPDX-License-Identifier: (GPL-2.0 OR MIT)
+/*
+ * Driver for the MDIO interface of Microsemi network switches.
+ *
+ * Author: Alexandre Belloni <alexandre.belloni@bootlin.com>
+ * Copyright (c) 2017 Microsemi Corporation
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/phy.h>
+#include <linux/platform_device.h>
+#include <linux/bitops.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/of_mdio.h>
+
+#define MSCC_MIIM_REG_STATUS		0x0
+#define		MSCC_MIIM_STATUS_STAT_PENDING	BIT(2)
+#define		MSCC_MIIM_STATUS_STAT_BUSY	BIT(3)
+#define MSCC_MIIM_REG_CMD		0x8
+#define		MSCC_MIIM_CMD_OPR_WRITE		BIT(1)
+#define		MSCC_MIIM_CMD_OPR_READ		BIT(2)
+#define		MSCC_MIIM_CMD_WRDATA_SHIFT	4
+#define		MSCC_MIIM_CMD_REGAD_SHIFT	20
+#define		MSCC_MIIM_CMD_PHYAD_SHIFT	25
+#define		MSCC_MIIM_CMD_VLD		BIT(31)
+#define MSCC_MIIM_REG_DATA		0xC
+#define		MSCC_MIIM_DATA_ERROR		(BIT(16) | BIT(17))
+
+#define MSCC_PHY_REG_PHY_CFG	0x0
+#define		PHY_CFG_PHY_ENA		(BIT(0) | BIT(1) | BIT(2) | BIT(3))
+#define		PHY_CFG_PHY_COMMON_RESET BIT(4)
+#define		PHY_CFG_PHY_RESET	(BIT(5) | BIT(6) | BIT(7) | BIT(8))
+#define MSCC_PHY_REG_PHY_STATUS	0x4
+
+struct mscc_miim_dev {
+	void __iomem *regs;
+	void __iomem *phy_regs;
+};
+
+/* When high resolution timers aren't built-in: we can't use usleep_range() as
+ * we would sleep way too long. Use udelay() instead.
+ */
+#define mscc_readl_poll_timeout(addr, val, cond, delay_us, timeout_us)	\
+({									\
+	if (!IS_ENABLED(CONFIG_HIGH_RES_TIMERS))			\
+		readl_poll_timeout_atomic(addr, val, cond, delay_us,	\
+					  timeout_us);			\
+	readl_poll_timeout(addr, val, cond, delay_us, timeout_us);	\
+})
+
+static int mscc_miim_wait_ready(struct mii_bus *bus)
+{
+	struct mscc_miim_dev *miim = bus->priv;
+	u32 val;
+
+	return mscc_readl_poll_timeout(miim->regs + MSCC_MIIM_REG_STATUS, val,
+				       !(val & MSCC_MIIM_STATUS_STAT_BUSY), 50,
+				       10000);
+}
+
+static int mscc_miim_wait_pending(struct mii_bus *bus)
+{
+	struct mscc_miim_dev *miim = bus->priv;
+	u32 val;
+
+	return mscc_readl_poll_timeout(miim->regs + MSCC_MIIM_REG_STATUS, val,
+				       !(val & MSCC_MIIM_STATUS_STAT_PENDING),
+				       50, 10000);
+}
+
+static int mscc_miim_read(struct mii_bus *bus, int mii_id, int regnum)
+{
+	struct mscc_miim_dev *miim = bus->priv;
+	u32 val;
+	int ret;
+
+	ret = mscc_miim_wait_pending(bus);
+	if (ret)
+		goto out;
+
+	writel(MSCC_MIIM_CMD_VLD | (mii_id << MSCC_MIIM_CMD_PHYAD_SHIFT) |
+	       (regnum << MSCC_MIIM_CMD_REGAD_SHIFT) | MSCC_MIIM_CMD_OPR_READ,
+	       miim->regs + MSCC_MIIM_REG_CMD);
+
+	ret = mscc_miim_wait_ready(bus);
+	if (ret)
+		goto out;
+
+	val = readl(miim->regs + MSCC_MIIM_REG_DATA);
+	if (val & MSCC_MIIM_DATA_ERROR) {
+		ret = -EIO;
+		goto out;
+	}
+
+	ret = val & 0xFFFF;
+out:
+	return ret;
+}
+
+static int mscc_miim_write(struct mii_bus *bus, int mii_id,
+			   int regnum, u16 value)
+{
+	struct mscc_miim_dev *miim = bus->priv;
+	int ret;
+
+	ret = mscc_miim_wait_pending(bus);
+	if (ret < 0)
+		goto out;
+
+	writel(MSCC_MIIM_CMD_VLD | (mii_id << MSCC_MIIM_CMD_PHYAD_SHIFT) |
+	       (regnum << MSCC_MIIM_CMD_REGAD_SHIFT) |
+	       (value << MSCC_MIIM_CMD_WRDATA_SHIFT) |
+	       MSCC_MIIM_CMD_OPR_WRITE,
+	       miim->regs + MSCC_MIIM_REG_CMD);
+
+out:
+	return ret;
+}
+
+static int mscc_miim_reset(struct mii_bus *bus)
+{
+	struct mscc_miim_dev *miim = bus->priv;
+
+	if (miim->phy_regs) {
+		writel(0, miim->phy_regs + MSCC_PHY_REG_PHY_CFG);
+		writel(0x1ff, miim->phy_regs + MSCC_PHY_REG_PHY_CFG);
+		mdelay(500);
+	}
+
+	return 0;
+}
+
+static int mscc_miim_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+	struct mii_bus *bus;
+	struct mscc_miim_dev *dev;
+	int ret;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -ENODEV;
+
+	bus = devm_mdiobus_alloc_size(&pdev->dev, sizeof(*dev));
+	if (!bus)
+		return -ENOMEM;
+
+	bus->name = "mscc_miim";
+	bus->read = mscc_miim_read;
+	bus->write = mscc_miim_write;
+	bus->reset = mscc_miim_reset;
+	snprintf(bus->id, MII_BUS_ID_SIZE, "%s-mii", dev_name(&pdev->dev));
+	bus->parent = &pdev->dev;
+
+	dev = bus->priv;
+	dev->regs = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(dev->regs)) {
+		dev_err(&pdev->dev, "Unable to map MIIM registers\n");
+		return PTR_ERR(dev->regs);
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+	if (res) {
+		dev->phy_regs = devm_ioremap_resource(&pdev->dev, res);
+		if (IS_ERR(dev->phy_regs)) {
+			dev_err(&pdev->dev, "Unable to map internal phy registers\n");
+			return PTR_ERR(dev->phy_regs);
+		}
+	}
+
+	ret = of_mdiobus_register(bus, pdev->dev.of_node);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "Cannot register MDIO bus (%d)\n", ret);
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, bus);
+
+	return 0;
+}
+
+static int mscc_miim_remove(struct platform_device *pdev)
+{
+	struct mii_bus *bus = platform_get_drvdata(pdev);
+
+	mdiobus_unregister(bus);
+
+	return 0;
+}
+
+static const struct of_device_id mscc_miim_match[] = {
+	{ .compatible = "mscc,ocelot-miim" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, mscc_miim_match);
+
+static struct platform_driver mscc_miim_driver = {
+	.probe = mscc_miim_probe,
+	.remove = mscc_miim_remove,
+	.driver = {
+		.name = "mscc-miim",
+		.of_match_table = mscc_miim_match,
+	},
+};
+
+module_platform_driver(mscc_miim_driver);
+
+MODULE_DESCRIPTION("Microsemi MIIM driver");
+MODULE_AUTHOR("Alexandre Belloni <alexandre.belloni@bootlin.com>");
+MODULE_LICENSE("Dual MIT/GPL");
diff --git a/drivers/net/mdio/mdio-mux-bcm-iproc.c b/drivers/net/mdio/mdio-mux-bcm-iproc.c
new file mode 100644
index 000000000000..42fb5f166136
--- /dev/null
+++ b/drivers/net/mdio/mdio-mux-bcm-iproc.c
@@ -0,0 +1,323 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2016 Broadcom
+ */
+#include <linux/clk.h>
+#include <linux/platform_device.h>
+#include <linux/device.h>
+#include <linux/of_mdio.h>
+#include <linux/module.h>
+#include <linux/phy.h>
+#include <linux/mdio-mux.h>
+#include <linux/delay.h>
+#include <linux/iopoll.h>
+
+#define MDIO_RATE_ADJ_EXT_OFFSET	0x000
+#define MDIO_RATE_ADJ_INT_OFFSET	0x004
+#define MDIO_RATE_ADJ_DIVIDENT_SHIFT	16
+
+#define MDIO_SCAN_CTRL_OFFSET		0x008
+#define MDIO_SCAN_CTRL_OVRIDE_EXT_MSTR	28
+
+#define MDIO_PARAM_OFFSET		0x23c
+#define MDIO_PARAM_MIIM_CYCLE		29
+#define MDIO_PARAM_INTERNAL_SEL		25
+#define MDIO_PARAM_BUS_ID		22
+#define MDIO_PARAM_C45_SEL		21
+#define MDIO_PARAM_PHY_ID		16
+#define MDIO_PARAM_PHY_DATA		0
+
+#define MDIO_READ_OFFSET		0x240
+#define MDIO_READ_DATA_MASK		0xffff
+#define MDIO_ADDR_OFFSET		0x244
+
+#define MDIO_CTRL_OFFSET		0x248
+#define MDIO_CTRL_WRITE_OP		0x1
+#define MDIO_CTRL_READ_OP		0x2
+
+#define MDIO_STAT_OFFSET		0x24c
+#define MDIO_STAT_DONE			1
+
+#define BUS_MAX_ADDR			32
+#define EXT_BUS_START_ADDR		16
+
+#define MDIO_REG_ADDR_SPACE_SIZE	0x250
+
+#define MDIO_OPERATING_FREQUENCY	11000000
+#define MDIO_RATE_ADJ_DIVIDENT		1
+
+struct iproc_mdiomux_desc {
+	void *mux_handle;
+	void __iomem *base;
+	struct device *dev;
+	struct mii_bus *mii_bus;
+	struct clk *core_clk;
+};
+
+static void mdio_mux_iproc_config(struct iproc_mdiomux_desc *md)
+{
+	u32 divisor;
+	u32 val;
+
+	/* Disable external mdio master access */
+	val = readl(md->base + MDIO_SCAN_CTRL_OFFSET);
+	val |= BIT(MDIO_SCAN_CTRL_OVRIDE_EXT_MSTR);
+	writel(val, md->base + MDIO_SCAN_CTRL_OFFSET);
+
+	if (md->core_clk) {
+		/* use rate adjust regs to derrive the mdio's operating
+		 * frequency from the specified core clock
+		 */
+		divisor = clk_get_rate(md->core_clk) / MDIO_OPERATING_FREQUENCY;
+		divisor = divisor / (MDIO_RATE_ADJ_DIVIDENT + 1);
+		val = divisor;
+		val |= MDIO_RATE_ADJ_DIVIDENT << MDIO_RATE_ADJ_DIVIDENT_SHIFT;
+		writel(val, md->base + MDIO_RATE_ADJ_EXT_OFFSET);
+		writel(val, md->base + MDIO_RATE_ADJ_INT_OFFSET);
+	}
+}
+
+static int iproc_mdio_wait_for_idle(void __iomem *base, bool result)
+{
+	u32 val;
+
+	return readl_poll_timeout(base + MDIO_STAT_OFFSET, val,
+				  (val & MDIO_STAT_DONE) == result,
+				  2000, 1000000);
+}
+
+/* start_miim_ops- Program and start MDIO transaction over mdio bus.
+ * @base: Base address
+ * @phyid: phyid of the selected bus.
+ * @reg: register offset to be read/written.
+ * @val :0 if read op else value to be written in @reg;
+ * @op: Operation that need to be carried out.
+ *      MDIO_CTRL_READ_OP: Read transaction.
+ *      MDIO_CTRL_WRITE_OP: Write transaction.
+ *
+ * Return value: Successful Read operation returns read reg values and write
+ *      operation returns 0. Failure operation returns negative error code.
+ */
+static int start_miim_ops(void __iomem *base,
+			  u16 phyid, u32 reg, u16 val, u32 op)
+{
+	u32 param;
+	int ret;
+
+	writel(0, base + MDIO_CTRL_OFFSET);
+	ret = iproc_mdio_wait_for_idle(base, 0);
+	if (ret)
+		goto err;
+
+	param = readl(base + MDIO_PARAM_OFFSET);
+	param |= phyid << MDIO_PARAM_PHY_ID;
+	param |= val << MDIO_PARAM_PHY_DATA;
+	if (reg & MII_ADDR_C45)
+		param |= BIT(MDIO_PARAM_C45_SEL);
+
+	writel(param, base + MDIO_PARAM_OFFSET);
+
+	writel(reg, base + MDIO_ADDR_OFFSET);
+
+	writel(op, base + MDIO_CTRL_OFFSET);
+
+	ret = iproc_mdio_wait_for_idle(base, 1);
+	if (ret)
+		goto err;
+
+	if (op == MDIO_CTRL_READ_OP)
+		ret = readl(base + MDIO_READ_OFFSET) & MDIO_READ_DATA_MASK;
+err:
+	return ret;
+}
+
+static int iproc_mdiomux_read(struct mii_bus *bus, int phyid, int reg)
+{
+	struct iproc_mdiomux_desc *md = bus->priv;
+	int ret;
+
+	ret = start_miim_ops(md->base, phyid, reg, 0, MDIO_CTRL_READ_OP);
+	if (ret < 0)
+		dev_err(&bus->dev, "mdiomux read operation failed!!!");
+
+	return ret;
+}
+
+static int iproc_mdiomux_write(struct mii_bus *bus,
+			       int phyid, int reg, u16 val)
+{
+	struct iproc_mdiomux_desc *md = bus->priv;
+	int ret;
+
+	/* Write val at reg offset */
+	ret = start_miim_ops(md->base, phyid, reg, val, MDIO_CTRL_WRITE_OP);
+	if (ret < 0)
+		dev_err(&bus->dev, "mdiomux write operation failed!!!");
+
+	return ret;
+}
+
+static int mdio_mux_iproc_switch_fn(int current_child, int desired_child,
+				    void *data)
+{
+	struct iproc_mdiomux_desc *md = data;
+	u32 param, bus_id;
+	bool bus_dir;
+
+	/* select bus and its properties */
+	bus_dir = (desired_child < EXT_BUS_START_ADDR);
+	bus_id = bus_dir ? desired_child : (desired_child - EXT_BUS_START_ADDR);
+
+	param = (bus_dir ? 1 : 0) << MDIO_PARAM_INTERNAL_SEL;
+	param |= (bus_id << MDIO_PARAM_BUS_ID);
+
+	writel(param, md->base + MDIO_PARAM_OFFSET);
+	return 0;
+}
+
+static int mdio_mux_iproc_probe(struct platform_device *pdev)
+{
+	struct iproc_mdiomux_desc *md;
+	struct mii_bus *bus;
+	struct resource *res;
+	int rc;
+
+	md = devm_kzalloc(&pdev->dev, sizeof(*md), GFP_KERNEL);
+	if (!md)
+		return -ENOMEM;
+	md->dev = &pdev->dev;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (res->start & 0xfff) {
+		/* For backward compatibility in case the
+		 * base address is specified with an offset.
+		 */
+		dev_info(&pdev->dev, "fix base address in dt-blob\n");
+		res->start &= ~0xfff;
+		res->end = res->start + MDIO_REG_ADDR_SPACE_SIZE - 1;
+	}
+	md->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(md->base)) {
+		dev_err(&pdev->dev, "failed to ioremap register\n");
+		return PTR_ERR(md->base);
+	}
+
+	md->mii_bus = devm_mdiobus_alloc(&pdev->dev);
+	if (!md->mii_bus) {
+		dev_err(&pdev->dev, "mdiomux bus alloc failed\n");
+		return -ENOMEM;
+	}
+
+	md->core_clk = devm_clk_get(&pdev->dev, NULL);
+	if (md->core_clk == ERR_PTR(-ENOENT) ||
+	    md->core_clk == ERR_PTR(-EINVAL))
+		md->core_clk = NULL;
+	else if (IS_ERR(md->core_clk))
+		return PTR_ERR(md->core_clk);
+
+	rc = clk_prepare_enable(md->core_clk);
+	if (rc) {
+		dev_err(&pdev->dev, "failed to enable core clk\n");
+		return rc;
+	}
+
+	bus = md->mii_bus;
+	bus->priv = md;
+	bus->name = "iProc MDIO mux bus";
+	snprintf(bus->id, MII_BUS_ID_SIZE, "%s-%d", pdev->name, pdev->id);
+	bus->parent = &pdev->dev;
+	bus->read = iproc_mdiomux_read;
+	bus->write = iproc_mdiomux_write;
+
+	bus->phy_mask = ~0;
+	bus->dev.of_node = pdev->dev.of_node;
+	rc = mdiobus_register(bus);
+	if (rc) {
+		dev_err(&pdev->dev, "mdiomux registration failed\n");
+		goto out_clk;
+	}
+
+	platform_set_drvdata(pdev, md);
+
+	rc = mdio_mux_init(md->dev, md->dev->of_node, mdio_mux_iproc_switch_fn,
+			   &md->mux_handle, md, md->mii_bus);
+	if (rc) {
+		dev_info(md->dev, "mdiomux initialization failed\n");
+		goto out_register;
+	}
+
+	mdio_mux_iproc_config(md);
+
+	dev_info(md->dev, "iProc mdiomux registered\n");
+	return 0;
+
+out_register:
+	mdiobus_unregister(bus);
+out_clk:
+	clk_disable_unprepare(md->core_clk);
+	return rc;
+}
+
+static int mdio_mux_iproc_remove(struct platform_device *pdev)
+{
+	struct iproc_mdiomux_desc *md = platform_get_drvdata(pdev);
+
+	mdio_mux_uninit(md->mux_handle);
+	mdiobus_unregister(md->mii_bus);
+	clk_disable_unprepare(md->core_clk);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int mdio_mux_iproc_suspend(struct device *dev)
+{
+	struct iproc_mdiomux_desc *md = dev_get_drvdata(dev);
+
+	clk_disable_unprepare(md->core_clk);
+
+	return 0;
+}
+
+static int mdio_mux_iproc_resume(struct device *dev)
+{
+	struct iproc_mdiomux_desc *md = dev_get_drvdata(dev);
+	int rc;
+
+	rc = clk_prepare_enable(md->core_clk);
+	if (rc) {
+		dev_err(md->dev, "failed to enable core clk\n");
+		return rc;
+	}
+	mdio_mux_iproc_config(md);
+
+	return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(mdio_mux_iproc_pm_ops,
+			 mdio_mux_iproc_suspend, mdio_mux_iproc_resume);
+
+static const struct of_device_id mdio_mux_iproc_match[] = {
+	{
+		.compatible = "brcm,mdio-mux-iproc",
+	},
+	{},
+};
+MODULE_DEVICE_TABLE(of, mdio_mux_iproc_match);
+
+static struct platform_driver mdiomux_iproc_driver = {
+	.driver = {
+		.name		= "mdio-mux-iproc",
+		.of_match_table = mdio_mux_iproc_match,
+		.pm		= &mdio_mux_iproc_pm_ops,
+	},
+	.probe		= mdio_mux_iproc_probe,
+	.remove		= mdio_mux_iproc_remove,
+};
+
+module_platform_driver(mdiomux_iproc_driver);
+
+MODULE_DESCRIPTION("iProc MDIO Mux Bus Driver");
+MODULE_AUTHOR("Pramod Kumar <pramod.kumar@broadcom.com>");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/net/mdio/mdio-mux-gpio.c b/drivers/net/mdio/mdio-mux-gpio.c
new file mode 100644
index 000000000000..10a758fdc9e6
--- /dev/null
+++ b/drivers/net/mdio/mdio-mux-gpio.c
@@ -0,0 +1,98 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2011, 2012 Cavium, Inc.
+ */
+
+#include <linux/platform_device.h>
+#include <linux/device.h>
+#include <linux/of_mdio.h>
+#include <linux/module.h>
+#include <linux/phy.h>
+#include <linux/mdio-mux.h>
+#include <linux/gpio/consumer.h>
+
+#define DRV_VERSION "1.1"
+#define DRV_DESCRIPTION "GPIO controlled MDIO bus multiplexer driver"
+
+struct mdio_mux_gpio_state {
+	struct gpio_descs *gpios;
+	void *mux_handle;
+};
+
+static int mdio_mux_gpio_switch_fn(int current_child, int desired_child,
+				   void *data)
+{
+	struct mdio_mux_gpio_state *s = data;
+	DECLARE_BITMAP(values, BITS_PER_TYPE(desired_child));
+
+	if (current_child == desired_child)
+		return 0;
+
+	values[0] = desired_child;
+
+	gpiod_set_array_value_cansleep(s->gpios->ndescs, s->gpios->desc,
+				       s->gpios->info, values);
+
+	return 0;
+}
+
+static int mdio_mux_gpio_probe(struct platform_device *pdev)
+{
+	struct mdio_mux_gpio_state *s;
+	struct gpio_descs *gpios;
+	int r;
+
+	gpios = devm_gpiod_get_array(&pdev->dev, NULL, GPIOD_OUT_LOW);
+	if (IS_ERR(gpios))
+		return PTR_ERR(gpios);
+
+	s = devm_kzalloc(&pdev->dev, sizeof(*s), GFP_KERNEL);
+	if (!s)
+		return -ENOMEM;
+
+	s->gpios = gpios;
+
+	r = mdio_mux_init(&pdev->dev, pdev->dev.of_node,
+			  mdio_mux_gpio_switch_fn, &s->mux_handle, s, NULL);
+
+	if (r != 0)
+		return r;
+
+	pdev->dev.platform_data = s;
+	return 0;
+}
+
+static int mdio_mux_gpio_remove(struct platform_device *pdev)
+{
+	struct mdio_mux_gpio_state *s = dev_get_platdata(&pdev->dev);
+	mdio_mux_uninit(s->mux_handle);
+	return 0;
+}
+
+static const struct of_device_id mdio_mux_gpio_match[] = {
+	{
+		.compatible = "mdio-mux-gpio",
+	},
+	{
+		/* Legacy compatible property. */
+		.compatible = "cavium,mdio-mux-sn74cbtlv3253",
+	},
+	{},
+};
+MODULE_DEVICE_TABLE(of, mdio_mux_gpio_match);
+
+static struct platform_driver mdio_mux_gpio_driver = {
+	.driver = {
+		.name		= "mdio-mux-gpio",
+		.of_match_table = mdio_mux_gpio_match,
+	},
+	.probe		= mdio_mux_gpio_probe,
+	.remove		= mdio_mux_gpio_remove,
+};
+
+module_platform_driver(mdio_mux_gpio_driver);
+
+MODULE_DESCRIPTION(DRV_DESCRIPTION);
+MODULE_VERSION(DRV_VERSION);
+MODULE_AUTHOR("David Daney");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/net/mdio/mdio-mux-meson-g12a.c b/drivers/net/mdio/mdio-mux-meson-g12a.c
new file mode 100644
index 000000000000..bf86c9c7a288
--- /dev/null
+++ b/drivers/net/mdio/mdio-mux-meson-g12a.c
@@ -0,0 +1,380 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2019 Baylibre, SAS.
+ * Author: Jerome Brunet <jbrunet@baylibre.com>
+ */
+
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/mdio-mux.h>
+#include <linux/module.h>
+#include <linux/phy.h>
+#include <linux/platform_device.h>
+
+#define ETH_PLL_STS		0x40
+#define ETH_PLL_CTL0		0x44
+#define  PLL_CTL0_LOCK_DIG	BIT(30)
+#define  PLL_CTL0_RST		BIT(29)
+#define  PLL_CTL0_EN		BIT(28)
+#define  PLL_CTL0_SEL		BIT(23)
+#define  PLL_CTL0_N		GENMASK(14, 10)
+#define  PLL_CTL0_M		GENMASK(8, 0)
+#define  PLL_LOCK_TIMEOUT	1000000
+#define  PLL_MUX_NUM_PARENT	2
+#define ETH_PLL_CTL1		0x48
+#define ETH_PLL_CTL2		0x4c
+#define ETH_PLL_CTL3		0x50
+#define ETH_PLL_CTL4		0x54
+#define ETH_PLL_CTL5		0x58
+#define ETH_PLL_CTL6		0x5c
+#define ETH_PLL_CTL7		0x60
+
+#define ETH_PHY_CNTL0		0x80
+#define   EPHY_G12A_ID		0x33010180
+#define ETH_PHY_CNTL1		0x84
+#define  PHY_CNTL1_ST_MODE	GENMASK(2, 0)
+#define  PHY_CNTL1_ST_PHYADD	GENMASK(7, 3)
+#define   EPHY_DFLT_ADD		8
+#define  PHY_CNTL1_MII_MODE	GENMASK(15, 14)
+#define   EPHY_MODE_RMII	0x1
+#define  PHY_CNTL1_CLK_EN	BIT(16)
+#define  PHY_CNTL1_CLKFREQ	BIT(17)
+#define  PHY_CNTL1_PHY_ENB	BIT(18)
+#define ETH_PHY_CNTL2		0x88
+#define  PHY_CNTL2_USE_INTERNAL	BIT(5)
+#define  PHY_CNTL2_SMI_SRC_MAC	BIT(6)
+#define  PHY_CNTL2_RX_CLK_EPHY	BIT(9)
+
+#define MESON_G12A_MDIO_EXTERNAL_ID 0
+#define MESON_G12A_MDIO_INTERNAL_ID 1
+
+struct g12a_mdio_mux {
+	bool pll_is_enabled;
+	void __iomem *regs;
+	void *mux_handle;
+	struct clk *pclk;
+	struct clk *pll;
+};
+
+struct g12a_ephy_pll {
+	void __iomem *base;
+	struct clk_hw hw;
+};
+
+#define g12a_ephy_pll_to_dev(_hw)			\
+	container_of(_hw, struct g12a_ephy_pll, hw)
+
+static unsigned long g12a_ephy_pll_recalc_rate(struct clk_hw *hw,
+					       unsigned long parent_rate)
+{
+	struct g12a_ephy_pll *pll = g12a_ephy_pll_to_dev(hw);
+	u32 val, m, n;
+
+	val = readl(pll->base + ETH_PLL_CTL0);
+	m = FIELD_GET(PLL_CTL0_M, val);
+	n = FIELD_GET(PLL_CTL0_N, val);
+
+	return parent_rate * m / n;
+}
+
+static int g12a_ephy_pll_enable(struct clk_hw *hw)
+{
+	struct g12a_ephy_pll *pll = g12a_ephy_pll_to_dev(hw);
+	u32 val = readl(pll->base + ETH_PLL_CTL0);
+
+	/* Apply both enable an reset */
+	val |= PLL_CTL0_RST | PLL_CTL0_EN;
+	writel(val, pll->base + ETH_PLL_CTL0);
+
+	/* Clear the reset to let PLL lock */
+	val &= ~PLL_CTL0_RST;
+	writel(val, pll->base + ETH_PLL_CTL0);
+
+	/* Poll on the digital lock instead of the usual analog lock
+	 * This is done because bit 31 is unreliable on some SoC. Bit
+	 * 31 may indicate that the PLL is not lock eventhough the clock
+	 * is actually running
+	 */
+	return readl_poll_timeout(pll->base + ETH_PLL_CTL0, val,
+				  val & PLL_CTL0_LOCK_DIG, 0, PLL_LOCK_TIMEOUT);
+}
+
+static void g12a_ephy_pll_disable(struct clk_hw *hw)
+{
+	struct g12a_ephy_pll *pll = g12a_ephy_pll_to_dev(hw);
+	u32 val;
+
+	val = readl(pll->base + ETH_PLL_CTL0);
+	val &= ~PLL_CTL0_EN;
+	val |= PLL_CTL0_RST;
+	writel(val, pll->base + ETH_PLL_CTL0);
+}
+
+static int g12a_ephy_pll_is_enabled(struct clk_hw *hw)
+{
+	struct g12a_ephy_pll *pll = g12a_ephy_pll_to_dev(hw);
+	unsigned int val;
+
+	val = readl(pll->base + ETH_PLL_CTL0);
+
+	return (val & PLL_CTL0_LOCK_DIG) ? 1 : 0;
+}
+
+static int g12a_ephy_pll_init(struct clk_hw *hw)
+{
+	struct g12a_ephy_pll *pll = g12a_ephy_pll_to_dev(hw);
+
+	/* Apply PLL HW settings */
+	writel(0x29c0040a, pll->base + ETH_PLL_CTL0);
+	writel(0x927e0000, pll->base + ETH_PLL_CTL1);
+	writel(0xac5f49e5, pll->base + ETH_PLL_CTL2);
+	writel(0x00000000, pll->base + ETH_PLL_CTL3);
+	writel(0x00000000, pll->base + ETH_PLL_CTL4);
+	writel(0x20200000, pll->base + ETH_PLL_CTL5);
+	writel(0x0000c002, pll->base + ETH_PLL_CTL6);
+	writel(0x00000023, pll->base + ETH_PLL_CTL7);
+
+	return 0;
+}
+
+static const struct clk_ops g12a_ephy_pll_ops = {
+	.recalc_rate	= g12a_ephy_pll_recalc_rate,
+	.is_enabled	= g12a_ephy_pll_is_enabled,
+	.enable		= g12a_ephy_pll_enable,
+	.disable	= g12a_ephy_pll_disable,
+	.init		= g12a_ephy_pll_init,
+};
+
+static int g12a_enable_internal_mdio(struct g12a_mdio_mux *priv)
+{
+	int ret;
+
+	/* Enable the phy clock */
+	if (!priv->pll_is_enabled) {
+		ret = clk_prepare_enable(priv->pll);
+		if (ret)
+			return ret;
+	}
+
+	priv->pll_is_enabled = true;
+
+	/* Initialize ephy control */
+	writel(EPHY_G12A_ID, priv->regs + ETH_PHY_CNTL0);
+	writel(FIELD_PREP(PHY_CNTL1_ST_MODE, 3) |
+	       FIELD_PREP(PHY_CNTL1_ST_PHYADD, EPHY_DFLT_ADD) |
+	       FIELD_PREP(PHY_CNTL1_MII_MODE, EPHY_MODE_RMII) |
+	       PHY_CNTL1_CLK_EN |
+	       PHY_CNTL1_CLKFREQ |
+	       PHY_CNTL1_PHY_ENB,
+	       priv->regs + ETH_PHY_CNTL1);
+	writel(PHY_CNTL2_USE_INTERNAL |
+	       PHY_CNTL2_SMI_SRC_MAC |
+	       PHY_CNTL2_RX_CLK_EPHY,
+	       priv->regs + ETH_PHY_CNTL2);
+
+	return 0;
+}
+
+static int g12a_enable_external_mdio(struct g12a_mdio_mux *priv)
+{
+	/* Reset the mdio bus mux */
+	writel_relaxed(0x0, priv->regs + ETH_PHY_CNTL2);
+
+	/* Disable the phy clock if enabled */
+	if (priv->pll_is_enabled) {
+		clk_disable_unprepare(priv->pll);
+		priv->pll_is_enabled = false;
+	}
+
+	return 0;
+}
+
+static int g12a_mdio_switch_fn(int current_child, int desired_child,
+			       void *data)
+{
+	struct g12a_mdio_mux *priv = dev_get_drvdata(data);
+
+	if (current_child == desired_child)
+		return 0;
+
+	switch (desired_child) {
+	case MESON_G12A_MDIO_EXTERNAL_ID:
+		return g12a_enable_external_mdio(priv);
+	case MESON_G12A_MDIO_INTERNAL_ID:
+		return g12a_enable_internal_mdio(priv);
+	default:
+		return -EINVAL;
+	}
+}
+
+static const struct of_device_id g12a_mdio_mux_match[] = {
+	{ .compatible = "amlogic,g12a-mdio-mux", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, g12a_mdio_mux_match);
+
+static int g12a_ephy_glue_clk_register(struct device *dev)
+{
+	struct g12a_mdio_mux *priv = dev_get_drvdata(dev);
+	const char *parent_names[PLL_MUX_NUM_PARENT];
+	struct clk_init_data init;
+	struct g12a_ephy_pll *pll;
+	struct clk_mux *mux;
+	struct clk *clk;
+	char *name;
+	int i;
+
+	/* get the mux parents */
+	for (i = 0; i < PLL_MUX_NUM_PARENT; i++) {
+		char in_name[8];
+
+		snprintf(in_name, sizeof(in_name), "clkin%d", i);
+		clk = devm_clk_get(dev, in_name);
+		if (IS_ERR(clk)) {
+			if (PTR_ERR(clk) != -EPROBE_DEFER)
+				dev_err(dev, "Missing clock %s\n", in_name);
+			return PTR_ERR(clk);
+		}
+
+		parent_names[i] = __clk_get_name(clk);
+	}
+
+	/* create the input mux */
+	mux = devm_kzalloc(dev, sizeof(*mux), GFP_KERNEL);
+	if (!mux)
+		return -ENOMEM;
+
+	name = kasprintf(GFP_KERNEL, "%s#mux", dev_name(dev));
+	if (!name)
+		return -ENOMEM;
+
+	init.name = name;
+	init.ops = &clk_mux_ro_ops;
+	init.flags = 0;
+	init.parent_names = parent_names;
+	init.num_parents = PLL_MUX_NUM_PARENT;
+
+	mux->reg = priv->regs + ETH_PLL_CTL0;
+	mux->shift = __ffs(PLL_CTL0_SEL);
+	mux->mask = PLL_CTL0_SEL >> mux->shift;
+	mux->hw.init = &init;
+
+	clk = devm_clk_register(dev, &mux->hw);
+	kfree(name);
+	if (IS_ERR(clk)) {
+		dev_err(dev, "failed to register input mux\n");
+		return PTR_ERR(clk);
+	}
+
+	/* create the pll */
+	pll = devm_kzalloc(dev, sizeof(*pll), GFP_KERNEL);
+	if (!pll)
+		return -ENOMEM;
+
+	name = kasprintf(GFP_KERNEL, "%s#pll", dev_name(dev));
+	if (!name)
+		return -ENOMEM;
+
+	init.name = name;
+	init.ops = &g12a_ephy_pll_ops;
+	init.flags = 0;
+	parent_names[0] = __clk_get_name(clk);
+	init.parent_names = parent_names;
+	init.num_parents = 1;
+
+	pll->base = priv->regs;
+	pll->hw.init = &init;
+
+	clk = devm_clk_register(dev, &pll->hw);
+	kfree(name);
+	if (IS_ERR(clk)) {
+		dev_err(dev, "failed to register input mux\n");
+		return PTR_ERR(clk);
+	}
+
+	priv->pll = clk;
+
+	return 0;
+}
+
+static int g12a_mdio_mux_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct g12a_mdio_mux *priv;
+	int ret;
+
+	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, priv);
+
+	priv->regs = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(priv->regs))
+		return PTR_ERR(priv->regs);
+
+	priv->pclk = devm_clk_get(dev, "pclk");
+	if (IS_ERR(priv->pclk)) {
+		ret = PTR_ERR(priv->pclk);
+		if (ret != -EPROBE_DEFER)
+			dev_err(dev, "failed to get peripheral clock\n");
+		return ret;
+	}
+
+	/* Make sure the device registers are clocked */
+	ret = clk_prepare_enable(priv->pclk);
+	if (ret) {
+		dev_err(dev, "failed to enable peripheral clock");
+		return ret;
+	}
+
+	/* Register PLL in CCF */
+	ret = g12a_ephy_glue_clk_register(dev);
+	if (ret)
+		goto err;
+
+	ret = mdio_mux_init(dev, dev->of_node, g12a_mdio_switch_fn,
+			    &priv->mux_handle, dev, NULL);
+	if (ret) {
+		if (ret != -EPROBE_DEFER)
+			dev_err(dev, "mdio multiplexer init failed: %d", ret);
+		goto err;
+	}
+
+	return 0;
+
+err:
+	clk_disable_unprepare(priv->pclk);
+	return ret;
+}
+
+static int g12a_mdio_mux_remove(struct platform_device *pdev)
+{
+	struct g12a_mdio_mux *priv = platform_get_drvdata(pdev);
+
+	mdio_mux_uninit(priv->mux_handle);
+
+	if (priv->pll_is_enabled)
+		clk_disable_unprepare(priv->pll);
+
+	clk_disable_unprepare(priv->pclk);
+
+	return 0;
+}
+
+static struct platform_driver g12a_mdio_mux_driver = {
+	.probe		= g12a_mdio_mux_probe,
+	.remove		= g12a_mdio_mux_remove,
+	.driver		= {
+		.name	= "g12a-mdio_mux",
+		.of_match_table = g12a_mdio_mux_match,
+	},
+};
+module_platform_driver(g12a_mdio_mux_driver);
+
+MODULE_DESCRIPTION("Amlogic G12a MDIO multiplexer driver");
+MODULE_AUTHOR("Jerome Brunet <jbrunet@baylibre.com>");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/net/mdio/mdio-mux-mmioreg.c b/drivers/net/mdio/mdio-mux-mmioreg.c
new file mode 100644
index 000000000000..d1a8780e24d8
--- /dev/null
+++ b/drivers/net/mdio/mdio-mux-mmioreg.c
@@ -0,0 +1,204 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Simple memory-mapped device MDIO MUX driver
+ *
+ * Author: Timur Tabi <timur@freescale.com>
+ *
+ * Copyright 2012 Freescale Semiconductor, Inc.
+ */
+
+#include <linux/platform_device.h>
+#include <linux/device.h>
+#include <linux/of_address.h>
+#include <linux/of_mdio.h>
+#include <linux/module.h>
+#include <linux/phy.h>
+#include <linux/mdio-mux.h>
+
+struct mdio_mux_mmioreg_state {
+	void *mux_handle;
+	phys_addr_t phys;
+	unsigned int iosize;
+	unsigned int mask;
+};
+
+/*
+ * MDIO multiplexing switch function
+ *
+ * This function is called by the mdio-mux layer when it thinks the mdio bus
+ * multiplexer needs to switch.
+ *
+ * 'current_child' is the current value of the mux register (masked via
+ * s->mask).
+ *
+ * 'desired_child' is the value of the 'reg' property of the target child MDIO
+ * node.
+ *
+ * The first time this function is called, current_child == -1.
+ *
+ * If current_child == desired_child, then the mux is already set to the
+ * correct bus.
+ */
+static int mdio_mux_mmioreg_switch_fn(int current_child, int desired_child,
+				      void *data)
+{
+	struct mdio_mux_mmioreg_state *s = data;
+
+	if (current_child ^ desired_child) {
+		void __iomem *p = ioremap(s->phys, s->iosize);
+		if (!p)
+			return -ENOMEM;
+
+		switch (s->iosize) {
+		case sizeof(uint8_t): {
+			uint8_t x, y;
+
+			x = ioread8(p);
+			y = (x & ~s->mask) | desired_child;
+			if (x != y) {
+				iowrite8((x & ~s->mask) | desired_child, p);
+				pr_debug("%s: %02x -> %02x\n", __func__, x, y);
+			}
+
+			break;
+		}
+		case sizeof(uint16_t): {
+			uint16_t x, y;
+
+			x = ioread16(p);
+			y = (x & ~s->mask) | desired_child;
+			if (x != y) {
+				iowrite16((x & ~s->mask) | desired_child, p);
+				pr_debug("%s: %04x -> %04x\n", __func__, x, y);
+			}
+
+			break;
+		}
+		case sizeof(uint32_t): {
+			uint32_t x, y;
+
+			x = ioread32(p);
+			y = (x & ~s->mask) | desired_child;
+			if (x != y) {
+				iowrite32((x & ~s->mask) | desired_child, p);
+				pr_debug("%s: %08x -> %08x\n", __func__, x, y);
+			}
+
+			break;
+		}
+		}
+
+		iounmap(p);
+	}
+
+	return 0;
+}
+
+static int mdio_mux_mmioreg_probe(struct platform_device *pdev)
+{
+	struct device_node *np2, *np = pdev->dev.of_node;
+	struct mdio_mux_mmioreg_state *s;
+	struct resource res;
+	const __be32 *iprop;
+	int len, ret;
+
+	dev_dbg(&pdev->dev, "probing node %pOF\n", np);
+
+	s = devm_kzalloc(&pdev->dev, sizeof(*s), GFP_KERNEL);
+	if (!s)
+		return -ENOMEM;
+
+	ret = of_address_to_resource(np, 0, &res);
+	if (ret) {
+		dev_err(&pdev->dev, "could not obtain memory map for node %pOF\n",
+			np);
+		return ret;
+	}
+	s->phys = res.start;
+
+	s->iosize = resource_size(&res);
+	if (s->iosize != sizeof(uint8_t) &&
+	    s->iosize != sizeof(uint16_t) &&
+	    s->iosize != sizeof(uint32_t)) {
+		dev_err(&pdev->dev, "only 8/16/32-bit registers are supported\n");
+		return -EINVAL;
+	}
+
+	iprop = of_get_property(np, "mux-mask", &len);
+	if (!iprop || len != sizeof(uint32_t)) {
+		dev_err(&pdev->dev, "missing or invalid mux-mask property\n");
+		return -ENODEV;
+	}
+	if (be32_to_cpup(iprop) >= BIT(s->iosize * 8)) {
+		dev_err(&pdev->dev, "only 8/16/32-bit registers are supported\n");
+		return -EINVAL;
+	}
+	s->mask = be32_to_cpup(iprop);
+
+	/*
+	 * Verify that the 'reg' property of each child MDIO bus does not
+	 * set any bits outside of the 'mask'.
+	 */
+	for_each_available_child_of_node(np, np2) {
+		iprop = of_get_property(np2, "reg", &len);
+		if (!iprop || len != sizeof(uint32_t)) {
+			dev_err(&pdev->dev, "mdio-mux child node %pOF is "
+				"missing a 'reg' property\n", np2);
+			of_node_put(np2);
+			return -ENODEV;
+		}
+		if (be32_to_cpup(iprop) & ~s->mask) {
+			dev_err(&pdev->dev, "mdio-mux child node %pOF has "
+				"a 'reg' value with unmasked bits\n",
+				np2);
+			of_node_put(np2);
+			return -ENODEV;
+		}
+	}
+
+	ret = mdio_mux_init(&pdev->dev, pdev->dev.of_node,
+			    mdio_mux_mmioreg_switch_fn,
+			    &s->mux_handle, s, NULL);
+	if (ret) {
+		if (ret != -EPROBE_DEFER)
+			dev_err(&pdev->dev,
+				"failed to register mdio-mux bus %pOF\n", np);
+		return ret;
+	}
+
+	pdev->dev.platform_data = s;
+
+	return 0;
+}
+
+static int mdio_mux_mmioreg_remove(struct platform_device *pdev)
+{
+	struct mdio_mux_mmioreg_state *s = dev_get_platdata(&pdev->dev);
+
+	mdio_mux_uninit(s->mux_handle);
+
+	return 0;
+}
+
+static const struct of_device_id mdio_mux_mmioreg_match[] = {
+	{
+		.compatible = "mdio-mux-mmioreg",
+	},
+	{},
+};
+MODULE_DEVICE_TABLE(of, mdio_mux_mmioreg_match);
+
+static struct platform_driver mdio_mux_mmioreg_driver = {
+	.driver = {
+		.name		= "mdio-mux-mmioreg",
+		.of_match_table = mdio_mux_mmioreg_match,
+	},
+	.probe		= mdio_mux_mmioreg_probe,
+	.remove		= mdio_mux_mmioreg_remove,
+};
+
+module_platform_driver(mdio_mux_mmioreg_driver);
+
+MODULE_AUTHOR("Timur Tabi <timur@freescale.com>");
+MODULE_DESCRIPTION("Memory-mapped device MDIO MUX driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/net/mdio/mdio-mux-multiplexer.c b/drivers/net/mdio/mdio-mux-multiplexer.c
new file mode 100644
index 000000000000..d6564381aa3e
--- /dev/null
+++ b/drivers/net/mdio/mdio-mux-multiplexer.c
@@ -0,0 +1,122 @@
+// SPDX-License-Identifier: GPL-2.0+
+/* MDIO bus multiplexer using kernel multiplexer subsystem
+ *
+ * Copyright 2019 NXP
+ */
+
+#include <linux/platform_device.h>
+#include <linux/mdio-mux.h>
+#include <linux/module.h>
+#include <linux/mux/consumer.h>
+
+struct mdio_mux_multiplexer_state {
+	struct mux_control *muxc;
+	bool do_deselect;
+	void *mux_handle;
+};
+
+/**
+ * mdio_mux_multiplexer_switch_fn - This function is called by the mdio-mux
+ *                                  layer when it thinks the mdio bus
+ *                                  multiplexer needs to switch.
+ * @current_child:  current value of the mux register.
+ * @desired_child: value of the 'reg' property of the target child MDIO node.
+ * @data: Private data used by this switch_fn passed to mdio_mux_init function
+ *        via mdio_mux_init(.., .., .., .., data, ..).
+ *
+ * The first time this function is called, current_child == -1.
+ * If current_child == desired_child, then the mux is already set to the
+ * correct bus.
+ */
+static int mdio_mux_multiplexer_switch_fn(int current_child, int desired_child,
+					  void *data)
+{
+	struct platform_device *pdev;
+	struct mdio_mux_multiplexer_state *s;
+	int ret = 0;
+
+	pdev = (struct platform_device *)data;
+	s = platform_get_drvdata(pdev);
+
+	if (!(current_child ^ desired_child))
+		return 0;
+
+	if (s->do_deselect)
+		ret = mux_control_deselect(s->muxc);
+	if (ret) {
+		dev_err(&pdev->dev, "mux_control_deselect failed in %s: %d\n",
+			__func__, ret);
+		return ret;
+	}
+
+	ret =  mux_control_select(s->muxc, desired_child);
+	if (!ret) {
+		dev_dbg(&pdev->dev, "%s %d -> %d\n", __func__, current_child,
+			desired_child);
+		s->do_deselect = true;
+	} else {
+		s->do_deselect = false;
+	}
+
+	return ret;
+}
+
+static int mdio_mux_multiplexer_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct mdio_mux_multiplexer_state *s;
+	int ret = 0;
+
+	s = devm_kzalloc(&pdev->dev, sizeof(*s), GFP_KERNEL);
+	if (!s)
+		return -ENOMEM;
+
+	s->muxc = devm_mux_control_get(dev, NULL);
+	if (IS_ERR(s->muxc)) {
+		ret = PTR_ERR(s->muxc);
+		if (ret != -EPROBE_DEFER)
+			dev_err(&pdev->dev, "Failed to get mux: %d\n", ret);
+		return ret;
+	}
+
+	platform_set_drvdata(pdev, s);
+
+	ret = mdio_mux_init(&pdev->dev, pdev->dev.of_node,
+			    mdio_mux_multiplexer_switch_fn, &s->mux_handle,
+			    pdev, NULL);
+
+	return ret;
+}
+
+static int mdio_mux_multiplexer_remove(struct platform_device *pdev)
+{
+	struct mdio_mux_multiplexer_state *s = platform_get_drvdata(pdev);
+
+	mdio_mux_uninit(s->mux_handle);
+
+	if (s->do_deselect)
+		mux_control_deselect(s->muxc);
+
+	return 0;
+}
+
+static const struct of_device_id mdio_mux_multiplexer_match[] = {
+	{ .compatible = "mdio-mux-multiplexer", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, mdio_mux_multiplexer_match);
+
+static struct platform_driver mdio_mux_multiplexer_driver = {
+	.driver = {
+		.name		= "mdio-mux-multiplexer",
+		.of_match_table	= mdio_mux_multiplexer_match,
+	},
+	.probe		= mdio_mux_multiplexer_probe,
+	.remove		= mdio_mux_multiplexer_remove,
+};
+
+module_platform_driver(mdio_mux_multiplexer_driver);
+
+MODULE_DESCRIPTION("MDIO bus multiplexer using kernel multiplexer subsystem");
+MODULE_AUTHOR("Pankaj Bansal <pankaj.bansal@nxp.com>");
+MODULE_LICENSE("GPL");
diff --git a/drivers/net/mdio/mdio-mux.c b/drivers/net/mdio/mdio-mux.c
new file mode 100644
index 000000000000..6a1d3540210b
--- /dev/null
+++ b/drivers/net/mdio/mdio-mux.c
@@ -0,0 +1,210 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2011, 2012 Cavium, Inc.
+ */
+
+#include <linux/platform_device.h>
+#include <linux/mdio-mux.h>
+#include <linux/of_mdio.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/phy.h>
+
+#define DRV_DESCRIPTION "MDIO bus multiplexer driver"
+
+struct mdio_mux_child_bus;
+
+struct mdio_mux_parent_bus {
+	struct mii_bus *mii_bus;
+	int current_child;
+	int parent_id;
+	void *switch_data;
+	int (*switch_fn)(int current_child, int desired_child, void *data);
+
+	/* List of our children linked through their next fields. */
+	struct mdio_mux_child_bus *children;
+};
+
+struct mdio_mux_child_bus {
+	struct mii_bus *mii_bus;
+	struct mdio_mux_parent_bus *parent;
+	struct mdio_mux_child_bus *next;
+	int bus_number;
+};
+
+/*
+ * The parent bus' lock is used to order access to the switch_fn.
+ */
+static int mdio_mux_read(struct mii_bus *bus, int phy_id, int regnum)
+{
+	struct mdio_mux_child_bus *cb = bus->priv;
+	struct mdio_mux_parent_bus *pb = cb->parent;
+	int r;
+
+	mutex_lock_nested(&pb->mii_bus->mdio_lock, MDIO_MUTEX_MUX);
+	r = pb->switch_fn(pb->current_child, cb->bus_number, pb->switch_data);
+	if (r)
+		goto out;
+
+	pb->current_child = cb->bus_number;
+
+	r = pb->mii_bus->read(pb->mii_bus, phy_id, regnum);
+out:
+	mutex_unlock(&pb->mii_bus->mdio_lock);
+
+	return r;
+}
+
+/*
+ * The parent bus' lock is used to order access to the switch_fn.
+ */
+static int mdio_mux_write(struct mii_bus *bus, int phy_id,
+			  int regnum, u16 val)
+{
+	struct mdio_mux_child_bus *cb = bus->priv;
+	struct mdio_mux_parent_bus *pb = cb->parent;
+
+	int r;
+
+	mutex_lock_nested(&pb->mii_bus->mdio_lock, MDIO_MUTEX_MUX);
+	r = pb->switch_fn(pb->current_child, cb->bus_number, pb->switch_data);
+	if (r)
+		goto out;
+
+	pb->current_child = cb->bus_number;
+
+	r = pb->mii_bus->write(pb->mii_bus, phy_id, regnum, val);
+out:
+	mutex_unlock(&pb->mii_bus->mdio_lock);
+
+	return r;
+}
+
+static int parent_count;
+
+int mdio_mux_init(struct device *dev,
+		  struct device_node *mux_node,
+		  int (*switch_fn)(int cur, int desired, void *data),
+		  void **mux_handle,
+		  void *data,
+		  struct mii_bus *mux_bus)
+{
+	struct device_node *parent_bus_node;
+	struct device_node *child_bus_node;
+	int r, ret_val;
+	struct mii_bus *parent_bus;
+	struct mdio_mux_parent_bus *pb;
+	struct mdio_mux_child_bus *cb;
+
+	if (!mux_node)
+		return -ENODEV;
+
+	if (!mux_bus) {
+		parent_bus_node = of_parse_phandle(mux_node,
+						   "mdio-parent-bus", 0);
+
+		if (!parent_bus_node)
+			return -ENODEV;
+
+		parent_bus = of_mdio_find_bus(parent_bus_node);
+		if (!parent_bus) {
+			ret_val = -EPROBE_DEFER;
+			goto err_parent_bus;
+		}
+	} else {
+		parent_bus_node = NULL;
+		parent_bus = mux_bus;
+		get_device(&parent_bus->dev);
+	}
+
+	pb = devm_kzalloc(dev, sizeof(*pb), GFP_KERNEL);
+	if (!pb) {
+		ret_val = -ENOMEM;
+		goto err_pb_kz;
+	}
+
+	pb->switch_data = data;
+	pb->switch_fn = switch_fn;
+	pb->current_child = -1;
+	pb->parent_id = parent_count++;
+	pb->mii_bus = parent_bus;
+
+	ret_val = -ENODEV;
+	for_each_available_child_of_node(mux_node, child_bus_node) {
+		int v;
+
+		r = of_property_read_u32(child_bus_node, "reg", &v);
+		if (r) {
+			dev_err(dev,
+				"Error: Failed to find reg for child %pOF\n",
+				child_bus_node);
+			continue;
+		}
+
+		cb = devm_kzalloc(dev, sizeof(*cb), GFP_KERNEL);
+		if (!cb) {
+			ret_val = -ENOMEM;
+			continue;
+		}
+		cb->bus_number = v;
+		cb->parent = pb;
+
+		cb->mii_bus = mdiobus_alloc();
+		if (!cb->mii_bus) {
+			ret_val = -ENOMEM;
+			devm_kfree(dev, cb);
+			continue;
+		}
+		cb->mii_bus->priv = cb;
+
+		cb->mii_bus->name = "mdio_mux";
+		snprintf(cb->mii_bus->id, MII_BUS_ID_SIZE, "%x.%x",
+			 pb->parent_id, v);
+		cb->mii_bus->parent = dev;
+		cb->mii_bus->read = mdio_mux_read;
+		cb->mii_bus->write = mdio_mux_write;
+		r = of_mdiobus_register(cb->mii_bus, child_bus_node);
+		if (r) {
+			dev_err(dev,
+				"Error: Failed to register MDIO bus for child %pOF\n",
+				child_bus_node);
+			mdiobus_free(cb->mii_bus);
+			devm_kfree(dev, cb);
+		} else {
+			cb->next = pb->children;
+			pb->children = cb;
+		}
+	}
+	if (pb->children) {
+		*mux_handle = pb;
+		return 0;
+	}
+
+	dev_err(dev, "Error: No acceptable child buses found\n");
+	devm_kfree(dev, pb);
+err_pb_kz:
+	put_device(&parent_bus->dev);
+err_parent_bus:
+	of_node_put(parent_bus_node);
+	return ret_val;
+}
+EXPORT_SYMBOL_GPL(mdio_mux_init);
+
+void mdio_mux_uninit(void *mux_handle)
+{
+	struct mdio_mux_parent_bus *pb = mux_handle;
+	struct mdio_mux_child_bus *cb = pb->children;
+
+	while (cb) {
+		mdiobus_unregister(cb->mii_bus);
+		mdiobus_free(cb->mii_bus);
+		cb = cb->next;
+	}
+
+	put_device(&pb->mii_bus->dev);
+}
+EXPORT_SYMBOL_GPL(mdio_mux_uninit);
+
+MODULE_DESCRIPTION(DRV_DESCRIPTION);
+MODULE_AUTHOR("David Daney");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/net/mdio/mdio-mvusb.c b/drivers/net/mdio/mdio-mvusb.c
new file mode 100644
index 000000000000..d5eabddfdf51
--- /dev/null
+++ b/drivers/net/mdio/mdio-mvusb.c
@@ -0,0 +1,120 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_mdio.h>
+#include <linux/phy.h>
+#include <linux/usb.h>
+
+#define USB_MARVELL_VID	0x1286
+
+static const struct usb_device_id mvusb_mdio_table[] = {
+	{ USB_DEVICE(USB_MARVELL_VID, 0x1fa4) },
+
+	{}
+};
+MODULE_DEVICE_TABLE(usb, mvusb_mdio_table);
+
+enum {
+	MVUSB_CMD_PREAMBLE0,
+	MVUSB_CMD_PREAMBLE1,
+	MVUSB_CMD_ADDR,
+	MVUSB_CMD_VAL,
+};
+
+struct mvusb_mdio {
+	struct usb_device *udev;
+	struct mii_bus *mdio;
+
+	__le16 buf[4];
+};
+
+static int mvusb_mdio_read(struct mii_bus *mdio, int dev, int reg)
+{
+	struct mvusb_mdio *mvusb = mdio->priv;
+	int err, alen;
+
+	if (dev & MII_ADDR_C45)
+		return -EOPNOTSUPP;
+
+	mvusb->buf[MVUSB_CMD_ADDR] = cpu_to_le16(0xa400 | (dev << 5) | reg);
+
+	err = usb_bulk_msg(mvusb->udev, usb_sndbulkpipe(mvusb->udev, 2),
+			   mvusb->buf, 6, &alen, 100);
+	if (err)
+		return err;
+
+	err = usb_bulk_msg(mvusb->udev, usb_rcvbulkpipe(mvusb->udev, 6),
+			   &mvusb->buf[MVUSB_CMD_VAL], 2, &alen, 100);
+	if (err)
+		return err;
+
+	return le16_to_cpu(mvusb->buf[MVUSB_CMD_VAL]);
+}
+
+static int mvusb_mdio_write(struct mii_bus *mdio, int dev, int reg, u16 val)
+{
+	struct mvusb_mdio *mvusb = mdio->priv;
+	int alen;
+
+	if (dev & MII_ADDR_C45)
+		return -EOPNOTSUPP;
+
+	mvusb->buf[MVUSB_CMD_ADDR] = cpu_to_le16(0x8000 | (dev << 5) | reg);
+	mvusb->buf[MVUSB_CMD_VAL]  = cpu_to_le16(val);
+
+	return usb_bulk_msg(mvusb->udev, usb_sndbulkpipe(mvusb->udev, 2),
+			    mvusb->buf, 8, &alen, 100);
+}
+
+static int mvusb_mdio_probe(struct usb_interface *interface,
+			    const struct usb_device_id *id)
+{
+	struct device *dev = &interface->dev;
+	struct mvusb_mdio *mvusb;
+	struct mii_bus *mdio;
+
+	mdio = devm_mdiobus_alloc_size(dev, sizeof(*mvusb));
+	if (!mdio)
+		return -ENOMEM;
+
+	mvusb = mdio->priv;
+	mvusb->mdio = mdio;
+	mvusb->udev = usb_get_dev(interface_to_usbdev(interface));
+
+	/* Reversed from USB PCAPs, no idea what these mean. */
+	mvusb->buf[MVUSB_CMD_PREAMBLE0] = cpu_to_le16(0xe800);
+	mvusb->buf[MVUSB_CMD_PREAMBLE1] = cpu_to_le16(0x0001);
+
+	snprintf(mdio->id, MII_BUS_ID_SIZE, "mvusb-%s", dev_name(dev));
+	mdio->name = mdio->id;
+	mdio->parent = dev;
+	mdio->read = mvusb_mdio_read;
+	mdio->write = mvusb_mdio_write;
+
+	usb_set_intfdata(interface, mvusb);
+	return of_mdiobus_register(mdio, dev->of_node);
+}
+
+static void mvusb_mdio_disconnect(struct usb_interface *interface)
+{
+	struct mvusb_mdio *mvusb = usb_get_intfdata(interface);
+	struct usb_device *udev = mvusb->udev;
+
+	mdiobus_unregister(mvusb->mdio);
+	usb_set_intfdata(interface, NULL);
+	usb_put_dev(udev);
+}
+
+static struct usb_driver mvusb_mdio_driver = {
+	.name       = "mvusb_mdio",
+	.id_table   = mvusb_mdio_table,
+	.probe      = mvusb_mdio_probe,
+	.disconnect = mvusb_mdio_disconnect,
+};
+
+module_usb_driver(mvusb_mdio_driver);
+
+MODULE_AUTHOR("Tobias Waldekranz <tobias@waldekranz.com>");
+MODULE_DESCRIPTION("Marvell USB MDIO Adapter");
+MODULE_LICENSE("GPL");
diff --git a/drivers/net/mdio/mdio-octeon.c b/drivers/net/mdio/mdio-octeon.c
new file mode 100644
index 000000000000..d1e1009d51af
--- /dev/null
+++ b/drivers/net/mdio/mdio-octeon.c
@@ -0,0 +1,115 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2009-2015 Cavium, Inc.
+ */
+
+#include <linux/platform_device.h>
+#include <linux/of_address.h>
+#include <linux/of_mdio.h>
+#include <linux/module.h>
+#include <linux/gfp.h>
+#include <linux/phy.h>
+#include <linux/io.h>
+
+#include "mdio-cavium.h"
+
+static int octeon_mdiobus_probe(struct platform_device *pdev)
+{
+	struct cavium_mdiobus *bus;
+	struct mii_bus *mii_bus;
+	struct resource *res_mem;
+	resource_size_t mdio_phys;
+	resource_size_t regsize;
+	union cvmx_smix_en smi_en;
+	int err = -ENOENT;
+
+	mii_bus = devm_mdiobus_alloc_size(&pdev->dev, sizeof(*bus));
+	if (!mii_bus)
+		return -ENOMEM;
+
+	res_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (res_mem == NULL) {
+		dev_err(&pdev->dev, "found no memory resource\n");
+		return -ENXIO;
+	}
+
+	bus = mii_bus->priv;
+	bus->mii_bus = mii_bus;
+	mdio_phys = res_mem->start;
+	regsize = resource_size(res_mem);
+
+	if (!devm_request_mem_region(&pdev->dev, mdio_phys, regsize,
+				     res_mem->name)) {
+		dev_err(&pdev->dev, "request_mem_region failed\n");
+		return -ENXIO;
+	}
+
+	bus->register_base = devm_ioremap(&pdev->dev, mdio_phys, regsize);
+	if (!bus->register_base) {
+		dev_err(&pdev->dev, "dev_ioremap failed\n");
+		return -ENOMEM;
+	}
+
+	smi_en.u64 = 0;
+	smi_en.s.en = 1;
+	oct_mdio_writeq(smi_en.u64, bus->register_base + SMI_EN);
+
+	bus->mii_bus->name = KBUILD_MODNAME;
+	snprintf(bus->mii_bus->id, MII_BUS_ID_SIZE, "%px", bus->register_base);
+	bus->mii_bus->parent = &pdev->dev;
+
+	bus->mii_bus->read = cavium_mdiobus_read;
+	bus->mii_bus->write = cavium_mdiobus_write;
+
+	platform_set_drvdata(pdev, bus);
+
+	err = of_mdiobus_register(bus->mii_bus, pdev->dev.of_node);
+	if (err)
+		goto fail_register;
+
+	dev_info(&pdev->dev, "Probed\n");
+
+	return 0;
+fail_register:
+	mdiobus_free(bus->mii_bus);
+	smi_en.u64 = 0;
+	oct_mdio_writeq(smi_en.u64, bus->register_base + SMI_EN);
+	return err;
+}
+
+static int octeon_mdiobus_remove(struct platform_device *pdev)
+{
+	struct cavium_mdiobus *bus;
+	union cvmx_smix_en smi_en;
+
+	bus = platform_get_drvdata(pdev);
+
+	mdiobus_unregister(bus->mii_bus);
+	mdiobus_free(bus->mii_bus);
+	smi_en.u64 = 0;
+	oct_mdio_writeq(smi_en.u64, bus->register_base + SMI_EN);
+	return 0;
+}
+
+static const struct of_device_id octeon_mdiobus_match[] = {
+	{
+		.compatible = "cavium,octeon-3860-mdio",
+	},
+	{},
+};
+MODULE_DEVICE_TABLE(of, octeon_mdiobus_match);
+
+static struct platform_driver octeon_mdiobus_driver = {
+	.driver = {
+		.name		= KBUILD_MODNAME,
+		.of_match_table = octeon_mdiobus_match,
+	},
+	.probe		= octeon_mdiobus_probe,
+	.remove		= octeon_mdiobus_remove,
+};
+
+module_platform_driver(octeon_mdiobus_driver);
+
+MODULE_DESCRIPTION("Cavium OCTEON MDIO bus driver");
+MODULE_AUTHOR("David Daney");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/net/mdio/mdio-sun4i.c b/drivers/net/mdio/mdio-sun4i.c
new file mode 100644
index 000000000000..f798de3276dc
--- /dev/null
+++ b/drivers/net/mdio/mdio-sun4i.c
@@ -0,0 +1,180 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Allwinner EMAC MDIO interface driver
+ *
+ * Copyright 2012-2013 Stefan Roese <sr@denx.de>
+ * Copyright 2013 Maxime Ripard <maxime.ripard@free-electrons.com>
+ *
+ * Based on the Linux driver provided by Allwinner:
+ * Copyright (C) 1997  Sten Wang
+ */
+
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/of_address.h>
+#include <linux/of_mdio.h>
+#include <linux/phy.h>
+#include <linux/platform_device.h>
+#include <linux/regulator/consumer.h>
+
+#define EMAC_MAC_MCMD_REG	(0x00)
+#define EMAC_MAC_MADR_REG	(0x04)
+#define EMAC_MAC_MWTD_REG	(0x08)
+#define EMAC_MAC_MRDD_REG	(0x0c)
+#define EMAC_MAC_MIND_REG	(0x10)
+#define EMAC_MAC_SSRR_REG	(0x14)
+
+#define MDIO_TIMEOUT		(msecs_to_jiffies(100))
+
+struct sun4i_mdio_data {
+	void __iomem		*membase;
+	struct regulator	*regulator;
+};
+
+static int sun4i_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
+{
+	struct sun4i_mdio_data *data = bus->priv;
+	unsigned long timeout_jiffies;
+	int value;
+
+	/* issue the phy address and reg */
+	writel((mii_id << 8) | regnum, data->membase + EMAC_MAC_MADR_REG);
+	/* pull up the phy io line */
+	writel(0x1, data->membase + EMAC_MAC_MCMD_REG);
+
+	/* Wait read complete */
+	timeout_jiffies = jiffies + MDIO_TIMEOUT;
+	while (readl(data->membase + EMAC_MAC_MIND_REG) & 0x1) {
+		if (time_is_before_jiffies(timeout_jiffies))
+			return -ETIMEDOUT;
+		msleep(1);
+	}
+
+	/* push down the phy io line */
+	writel(0x0, data->membase + EMAC_MAC_MCMD_REG);
+	/* and read data */
+	value = readl(data->membase + EMAC_MAC_MRDD_REG);
+
+	return value;
+}
+
+static int sun4i_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
+			    u16 value)
+{
+	struct sun4i_mdio_data *data = bus->priv;
+	unsigned long timeout_jiffies;
+
+	/* issue the phy address and reg */
+	writel((mii_id << 8) | regnum, data->membase + EMAC_MAC_MADR_REG);
+	/* pull up the phy io line */
+	writel(0x1, data->membase + EMAC_MAC_MCMD_REG);
+
+	/* Wait read complete */
+	timeout_jiffies = jiffies + MDIO_TIMEOUT;
+	while (readl(data->membase + EMAC_MAC_MIND_REG) & 0x1) {
+		if (time_is_before_jiffies(timeout_jiffies))
+			return -ETIMEDOUT;
+		msleep(1);
+	}
+
+	/* push down the phy io line */
+	writel(0x0, data->membase + EMAC_MAC_MCMD_REG);
+	/* and write data */
+	writel(value, data->membase + EMAC_MAC_MWTD_REG);
+
+	return 0;
+}
+
+static int sun4i_mdio_probe(struct platform_device *pdev)
+{
+	struct device_node *np = pdev->dev.of_node;
+	struct mii_bus *bus;
+	struct sun4i_mdio_data *data;
+	int ret;
+
+	bus = mdiobus_alloc_size(sizeof(*data));
+	if (!bus)
+		return -ENOMEM;
+
+	bus->name = "sun4i_mii_bus";
+	bus->read = &sun4i_mdio_read;
+	bus->write = &sun4i_mdio_write;
+	snprintf(bus->id, MII_BUS_ID_SIZE, "%s-mii", dev_name(&pdev->dev));
+	bus->parent = &pdev->dev;
+
+	data = bus->priv;
+	data->membase = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(data->membase)) {
+		ret = PTR_ERR(data->membase);
+		goto err_out_free_mdiobus;
+	}
+
+	data->regulator = devm_regulator_get(&pdev->dev, "phy");
+	if (IS_ERR(data->regulator)) {
+		if (PTR_ERR(data->regulator) == -EPROBE_DEFER) {
+			ret = -EPROBE_DEFER;
+			goto err_out_free_mdiobus;
+		}
+
+		dev_info(&pdev->dev, "no regulator found\n");
+		data->regulator = NULL;
+	} else {
+		ret = regulator_enable(data->regulator);
+		if (ret)
+			goto err_out_free_mdiobus;
+	}
+
+	ret = of_mdiobus_register(bus, np);
+	if (ret < 0)
+		goto err_out_disable_regulator;
+
+	platform_set_drvdata(pdev, bus);
+
+	return 0;
+
+err_out_disable_regulator:
+	if (data->regulator)
+		regulator_disable(data->regulator);
+err_out_free_mdiobus:
+	mdiobus_free(bus);
+	return ret;
+}
+
+static int sun4i_mdio_remove(struct platform_device *pdev)
+{
+	struct mii_bus *bus = platform_get_drvdata(pdev);
+	struct sun4i_mdio_data *data = bus->priv;
+
+	mdiobus_unregister(bus);
+	if (data->regulator)
+		regulator_disable(data->regulator);
+	mdiobus_free(bus);
+
+	return 0;
+}
+
+static const struct of_device_id sun4i_mdio_dt_ids[] = {
+	{ .compatible = "allwinner,sun4i-a10-mdio" },
+
+	/* Deprecated */
+	{ .compatible = "allwinner,sun4i-mdio" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, sun4i_mdio_dt_ids);
+
+static struct platform_driver sun4i_mdio_driver = {
+	.probe = sun4i_mdio_probe,
+	.remove = sun4i_mdio_remove,
+	.driver = {
+		.name = "sun4i-mdio",
+		.of_match_table = sun4i_mdio_dt_ids,
+	},
+};
+
+module_platform_driver(sun4i_mdio_driver);
+
+MODULE_DESCRIPTION("Allwinner EMAC MDIO interface driver");
+MODULE_AUTHOR("Maxime Ripard <maxime.ripard@free-electrons.com>");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/net/mdio/mdio-thunder.c b/drivers/net/mdio/mdio-thunder.c
new file mode 100644
index 000000000000..3d7eda99d34e
--- /dev/null
+++ b/drivers/net/mdio/mdio-thunder.c
@@ -0,0 +1,152 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2009-2016 Cavium, Inc.
+ */
+
+#include <linux/of_address.h>
+#include <linux/of_mdio.h>
+#include <linux/module.h>
+#include <linux/gfp.h>
+#include <linux/phy.h>
+#include <linux/io.h>
+#include <linux/acpi.h>
+#include <linux/pci.h>
+
+#include "mdio-cavium.h"
+
+struct thunder_mdiobus_nexus {
+	void __iomem *bar0;
+	struct cavium_mdiobus *buses[4];
+};
+
+static int thunder_mdiobus_pci_probe(struct pci_dev *pdev,
+				     const struct pci_device_id *ent)
+{
+	struct device_node *node;
+	struct fwnode_handle *fwn;
+	struct thunder_mdiobus_nexus *nexus;
+	int err;
+	int i;
+
+	nexus = devm_kzalloc(&pdev->dev, sizeof(*nexus), GFP_KERNEL);
+	if (!nexus)
+		return -ENOMEM;
+
+	pci_set_drvdata(pdev, nexus);
+
+	err = pcim_enable_device(pdev);
+	if (err) {
+		dev_err(&pdev->dev, "Failed to enable PCI device\n");
+		pci_set_drvdata(pdev, NULL);
+		return err;
+	}
+
+	err = pci_request_regions(pdev, KBUILD_MODNAME);
+	if (err) {
+		dev_err(&pdev->dev, "pci_request_regions failed\n");
+		goto err_disable_device;
+	}
+
+	nexus->bar0 = pcim_iomap(pdev, 0, pci_resource_len(pdev, 0));
+	if (!nexus->bar0) {
+		err = -ENOMEM;
+		goto err_release_regions;
+	}
+
+	i = 0;
+	device_for_each_child_node(&pdev->dev, fwn) {
+		struct resource r;
+		struct mii_bus *mii_bus;
+		struct cavium_mdiobus *bus;
+		union cvmx_smix_en smi_en;
+
+		/* If it is not an OF node we cannot handle it yet, so
+		 * exit the loop.
+		 */
+		node = to_of_node(fwn);
+		if (!node)
+			break;
+
+		err = of_address_to_resource(node, 0, &r);
+		if (err) {
+			dev_err(&pdev->dev,
+				"Couldn't translate address for \"%pOFn\"\n",
+				node);
+			break;
+		}
+
+		mii_bus = devm_mdiobus_alloc_size(&pdev->dev, sizeof(*bus));
+		if (!mii_bus)
+			break;
+		bus = mii_bus->priv;
+		bus->mii_bus = mii_bus;
+
+		nexus->buses[i] = bus;
+		i++;
+
+		bus->register_base = nexus->bar0 +
+			r.start - pci_resource_start(pdev, 0);
+
+		smi_en.u64 = 0;
+		smi_en.s.en = 1;
+		oct_mdio_writeq(smi_en.u64, bus->register_base + SMI_EN);
+		bus->mii_bus->name = KBUILD_MODNAME;
+		snprintf(bus->mii_bus->id, MII_BUS_ID_SIZE, "%llx", r.start);
+		bus->mii_bus->parent = &pdev->dev;
+		bus->mii_bus->read = cavium_mdiobus_read;
+		bus->mii_bus->write = cavium_mdiobus_write;
+
+		err = of_mdiobus_register(bus->mii_bus, node);
+		if (err)
+			dev_err(&pdev->dev, "of_mdiobus_register failed\n");
+
+		dev_info(&pdev->dev, "Added bus at %llx\n", r.start);
+		if (i >= ARRAY_SIZE(nexus->buses))
+			break;
+	}
+	return 0;
+
+err_release_regions:
+	pci_release_regions(pdev);
+
+err_disable_device:
+	pci_set_drvdata(pdev, NULL);
+	return err;
+}
+
+static void thunder_mdiobus_pci_remove(struct pci_dev *pdev)
+{
+	int i;
+	struct thunder_mdiobus_nexus *nexus = pci_get_drvdata(pdev);
+
+	for (i = 0; i < ARRAY_SIZE(nexus->buses); i++) {
+		struct cavium_mdiobus *bus = nexus->buses[i];
+
+		if (!bus)
+			continue;
+
+		mdiobus_unregister(bus->mii_bus);
+		mdiobus_free(bus->mii_bus);
+		oct_mdio_writeq(0, bus->register_base + SMI_EN);
+	}
+	pci_release_regions(pdev);
+	pci_set_drvdata(pdev, NULL);
+}
+
+static const struct pci_device_id thunder_mdiobus_id_table[] = {
+	{ PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, 0xa02b) },
+	{ 0, } /* End of table. */
+};
+MODULE_DEVICE_TABLE(pci, thunder_mdiobus_id_table);
+
+static struct pci_driver thunder_mdiobus_driver = {
+	.name = KBUILD_MODNAME,
+	.id_table = thunder_mdiobus_id_table,
+	.probe = thunder_mdiobus_pci_probe,
+	.remove = thunder_mdiobus_pci_remove,
+};
+
+module_pci_driver(thunder_mdiobus_driver);
+
+MODULE_DESCRIPTION("Cavium ThunderX MDIO bus driver");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/net/mdio/mdio-xgene.c b/drivers/net/mdio/mdio-xgene.c
new file mode 100644
index 000000000000..461207cdf5d6
--- /dev/null
+++ b/drivers/net/mdio/mdio-xgene.c
@@ -0,0 +1,466 @@
+// SPDX-License-Identifier: GPL-2.0+
+/* Applied Micro X-Gene SoC MDIO Driver
+ *
+ * Copyright (c) 2016, Applied Micro Circuits Corporation
+ * Author: Iyappan Subramanian <isubramanian@apm.com>
+ */
+
+#include <linux/acpi.h>
+#include <linux/clk.h>
+#include <linux/device.h>
+#include <linux/efi.h>
+#include <linux/if_vlan.h>
+#include <linux/io.h>
+#include <linux/mdio/mdio-xgene.h>
+#include <linux/module.h>
+#include <linux/of_platform.h>
+#include <linux/of_net.h>
+#include <linux/of_mdio.h>
+#include <linux/prefetch.h>
+#include <linux/phy.h>
+#include <net/ip.h>
+
+static bool xgene_mdio_status;
+
+u32 xgene_mdio_rd_mac(struct xgene_mdio_pdata *pdata, u32 rd_addr)
+{
+	void __iomem *addr, *rd, *cmd, *cmd_done;
+	u32 done, rd_data = BUSY_MASK;
+	u8 wait = 10;
+
+	addr = pdata->mac_csr_addr + MAC_ADDR_REG_OFFSET;
+	rd = pdata->mac_csr_addr + MAC_READ_REG_OFFSET;
+	cmd = pdata->mac_csr_addr + MAC_COMMAND_REG_OFFSET;
+	cmd_done = pdata->mac_csr_addr + MAC_COMMAND_DONE_REG_OFFSET;
+
+	spin_lock(&pdata->mac_lock);
+	iowrite32(rd_addr, addr);
+	iowrite32(XGENE_ENET_RD_CMD, cmd);
+
+	while (!(done = ioread32(cmd_done)) && wait--)
+		udelay(1);
+
+	if (done)
+		rd_data = ioread32(rd);
+
+	iowrite32(0, cmd);
+	spin_unlock(&pdata->mac_lock);
+
+	return rd_data;
+}
+EXPORT_SYMBOL(xgene_mdio_rd_mac);
+
+void xgene_mdio_wr_mac(struct xgene_mdio_pdata *pdata, u32 wr_addr, u32 data)
+{
+	void __iomem *addr, *wr, *cmd, *cmd_done;
+	u8 wait = 10;
+	u32 done;
+
+	addr = pdata->mac_csr_addr + MAC_ADDR_REG_OFFSET;
+	wr = pdata->mac_csr_addr + MAC_WRITE_REG_OFFSET;
+	cmd = pdata->mac_csr_addr + MAC_COMMAND_REG_OFFSET;
+	cmd_done = pdata->mac_csr_addr + MAC_COMMAND_DONE_REG_OFFSET;
+
+	spin_lock(&pdata->mac_lock);
+	iowrite32(wr_addr, addr);
+	iowrite32(data, wr);
+	iowrite32(XGENE_ENET_WR_CMD, cmd);
+
+	while (!(done = ioread32(cmd_done)) && wait--)
+		udelay(1);
+
+	if (!done)
+		pr_err("MCX mac write failed, addr: 0x%04x\n", wr_addr);
+
+	iowrite32(0, cmd);
+	spin_unlock(&pdata->mac_lock);
+}
+EXPORT_SYMBOL(xgene_mdio_wr_mac);
+
+int xgene_mdio_rgmii_read(struct mii_bus *bus, int phy_id, int reg)
+{
+	struct xgene_mdio_pdata *pdata = (struct xgene_mdio_pdata *)bus->priv;
+	u32 data, done;
+	u8 wait = 10;
+
+	data = SET_VAL(PHY_ADDR, phy_id) | SET_VAL(REG_ADDR, reg);
+	xgene_mdio_wr_mac(pdata, MII_MGMT_ADDRESS_ADDR, data);
+	xgene_mdio_wr_mac(pdata, MII_MGMT_COMMAND_ADDR, READ_CYCLE_MASK);
+	do {
+		usleep_range(5, 10);
+		done = xgene_mdio_rd_mac(pdata, MII_MGMT_INDICATORS_ADDR);
+	} while ((done & BUSY_MASK) && wait--);
+
+	if (done & BUSY_MASK) {
+		dev_err(&bus->dev, "MII_MGMT read failed\n");
+		return -EBUSY;
+	}
+
+	data = xgene_mdio_rd_mac(pdata, MII_MGMT_STATUS_ADDR);
+	xgene_mdio_wr_mac(pdata, MII_MGMT_COMMAND_ADDR, 0);
+
+	return data;
+}
+EXPORT_SYMBOL(xgene_mdio_rgmii_read);
+
+int xgene_mdio_rgmii_write(struct mii_bus *bus, int phy_id, int reg, u16 data)
+{
+	struct xgene_mdio_pdata *pdata = (struct xgene_mdio_pdata *)bus->priv;
+	u32 val, done;
+	u8 wait = 10;
+
+	val = SET_VAL(PHY_ADDR, phy_id) | SET_VAL(REG_ADDR, reg);
+	xgene_mdio_wr_mac(pdata, MII_MGMT_ADDRESS_ADDR, val);
+
+	xgene_mdio_wr_mac(pdata, MII_MGMT_CONTROL_ADDR, data);
+	do {
+		usleep_range(5, 10);
+		done = xgene_mdio_rd_mac(pdata, MII_MGMT_INDICATORS_ADDR);
+	} while ((done & BUSY_MASK) && wait--);
+
+	if (done & BUSY_MASK) {
+		dev_err(&bus->dev, "MII_MGMT write failed\n");
+		return -EBUSY;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(xgene_mdio_rgmii_write);
+
+static u32 xgene_menet_rd_diag_csr(struct xgene_mdio_pdata *pdata, u32 offset)
+{
+	return ioread32(pdata->diag_csr_addr + offset);
+}
+
+static void xgene_menet_wr_diag_csr(struct xgene_mdio_pdata *pdata,
+				    u32 offset, u32 val)
+{
+	iowrite32(val, pdata->diag_csr_addr + offset);
+}
+
+static int xgene_enet_ecc_init(struct xgene_mdio_pdata *pdata)
+{
+	u32 data;
+	u8 wait = 10;
+
+	xgene_menet_wr_diag_csr(pdata, MENET_CFG_MEM_RAM_SHUTDOWN_ADDR, 0x0);
+	do {
+		usleep_range(100, 110);
+		data = xgene_menet_rd_diag_csr(pdata, MENET_BLOCK_MEM_RDY_ADDR);
+	} while ((data != 0xffffffff) && wait--);
+
+	if (data != 0xffffffff) {
+		dev_err(pdata->dev, "Failed to release memory from shutdown\n");
+		return -ENODEV;
+	}
+
+	return 0;
+}
+
+static void xgene_gmac_reset(struct xgene_mdio_pdata *pdata)
+{
+	xgene_mdio_wr_mac(pdata, MAC_CONFIG_1_ADDR, SOFT_RESET);
+	xgene_mdio_wr_mac(pdata, MAC_CONFIG_1_ADDR, 0);
+}
+
+static int xgene_mdio_reset(struct xgene_mdio_pdata *pdata)
+{
+	int ret;
+
+	if (pdata->dev->of_node) {
+		clk_prepare_enable(pdata->clk);
+		udelay(5);
+		clk_disable_unprepare(pdata->clk);
+		udelay(5);
+		clk_prepare_enable(pdata->clk);
+		udelay(5);
+	} else {
+#ifdef CONFIG_ACPI
+		acpi_evaluate_object(ACPI_HANDLE(pdata->dev),
+				     "_RST", NULL, NULL);
+#endif
+	}
+
+	ret = xgene_enet_ecc_init(pdata);
+	if (ret) {
+		if (pdata->dev->of_node)
+			clk_disable_unprepare(pdata->clk);
+		return ret;
+	}
+	xgene_gmac_reset(pdata);
+
+	return 0;
+}
+
+static void xgene_enet_rd_mdio_csr(void __iomem *base_addr,
+				   u32 offset, u32 *val)
+{
+	void __iomem *addr = base_addr  + offset;
+
+	*val = ioread32(addr);
+}
+
+static void xgene_enet_wr_mdio_csr(void __iomem *base_addr,
+				   u32 offset, u32 val)
+{
+	void __iomem *addr = base_addr  + offset;
+
+	iowrite32(val, addr);
+}
+
+static int xgene_xfi_mdio_write(struct mii_bus *bus, int phy_id,
+				int reg, u16 data)
+{
+	void __iomem *addr = (void __iomem *)bus->priv;
+	int timeout = 100;
+	u32 status, val;
+
+	val = SET_VAL(HSTPHYADX, phy_id) | SET_VAL(HSTREGADX, reg) |
+	      SET_VAL(HSTMIIMWRDAT, data);
+	xgene_enet_wr_mdio_csr(addr, MIIM_FIELD_ADDR, val);
+
+	val = HSTLDCMD | SET_VAL(HSTMIIMCMD, MIIM_CMD_LEGACY_WRITE);
+	xgene_enet_wr_mdio_csr(addr, MIIM_COMMAND_ADDR, val);
+
+	do {
+		usleep_range(5, 10);
+		xgene_enet_rd_mdio_csr(addr, MIIM_INDICATOR_ADDR, &status);
+	} while ((status & BUSY_MASK) && timeout--);
+
+	xgene_enet_wr_mdio_csr(addr, MIIM_COMMAND_ADDR, 0);
+
+	return 0;
+}
+
+static int xgene_xfi_mdio_read(struct mii_bus *bus, int phy_id, int reg)
+{
+	void __iomem *addr = (void __iomem *)bus->priv;
+	u32 data, status, val;
+	int timeout = 100;
+
+	val = SET_VAL(HSTPHYADX, phy_id) | SET_VAL(HSTREGADX, reg);
+	xgene_enet_wr_mdio_csr(addr, MIIM_FIELD_ADDR, val);
+
+	val = HSTLDCMD | SET_VAL(HSTMIIMCMD, MIIM_CMD_LEGACY_READ);
+	xgene_enet_wr_mdio_csr(addr, MIIM_COMMAND_ADDR, val);
+
+	do {
+		usleep_range(5, 10);
+		xgene_enet_rd_mdio_csr(addr, MIIM_INDICATOR_ADDR, &status);
+	} while ((status & BUSY_MASK) && timeout--);
+
+	if (status & BUSY_MASK) {
+		pr_err("XGENET_MII_MGMT write failed\n");
+		return -EBUSY;
+	}
+
+	xgene_enet_rd_mdio_csr(addr, MIIMRD_FIELD_ADDR, &data);
+	xgene_enet_wr_mdio_csr(addr, MIIM_COMMAND_ADDR, 0);
+
+	return data;
+}
+
+struct phy_device *xgene_enet_phy_register(struct mii_bus *bus, int phy_addr)
+{
+	struct phy_device *phy_dev;
+
+	phy_dev = get_phy_device(bus, phy_addr, false);
+	if (!phy_dev || IS_ERR(phy_dev))
+		return NULL;
+
+	if (phy_device_register(phy_dev))
+		phy_device_free(phy_dev);
+
+	return phy_dev;
+}
+EXPORT_SYMBOL(xgene_enet_phy_register);
+
+#ifdef CONFIG_ACPI
+static acpi_status acpi_register_phy(acpi_handle handle, u32 lvl,
+				     void *context, void **ret)
+{
+	struct mii_bus *mdio = context;
+	struct acpi_device *adev;
+	struct phy_device *phy_dev;
+	const union acpi_object *obj;
+	u32 phy_addr;
+
+	if (acpi_bus_get_device(handle, &adev))
+		return AE_OK;
+
+	if (acpi_dev_get_property(adev, "phy-channel", ACPI_TYPE_INTEGER, &obj))
+		return AE_OK;
+	phy_addr = obj->integer.value;
+
+	phy_dev = xgene_enet_phy_register(mdio, phy_addr);
+	adev->driver_data = phy_dev;
+
+	return AE_OK;
+}
+#endif
+
+static const struct of_device_id xgene_mdio_of_match[] = {
+	{
+		.compatible = "apm,xgene-mdio-rgmii",
+		.data = (void *)XGENE_MDIO_RGMII
+	},
+	{
+		.compatible = "apm,xgene-mdio-xfi",
+		.data = (void *)XGENE_MDIO_XFI
+	},
+	{},
+};
+MODULE_DEVICE_TABLE(of, xgene_mdio_of_match);
+
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id xgene_mdio_acpi_match[] = {
+	{ "APMC0D65", XGENE_MDIO_RGMII },
+	{ "APMC0D66", XGENE_MDIO_XFI },
+	{ }
+};
+
+MODULE_DEVICE_TABLE(acpi, xgene_mdio_acpi_match);
+#endif
+
+
+static int xgene_mdio_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct mii_bus *mdio_bus;
+	const struct of_device_id *of_id;
+	struct xgene_mdio_pdata *pdata;
+	void __iomem *csr_base;
+	int mdio_id = 0, ret = 0;
+
+	of_id = of_match_device(xgene_mdio_of_match, &pdev->dev);
+	if (of_id) {
+		mdio_id = (enum xgene_mdio_id)of_id->data;
+	} else {
+#ifdef CONFIG_ACPI
+		const struct acpi_device_id *acpi_id;
+
+		acpi_id = acpi_match_device(xgene_mdio_acpi_match, &pdev->dev);
+		if (acpi_id)
+			mdio_id = (enum xgene_mdio_id)acpi_id->driver_data;
+#endif
+	}
+
+	if (!mdio_id)
+		return -ENODEV;
+
+	pdata = devm_kzalloc(dev, sizeof(struct xgene_mdio_pdata), GFP_KERNEL);
+	if (!pdata)
+		return -ENOMEM;
+	pdata->mdio_id = mdio_id;
+	pdata->dev = dev;
+
+	csr_base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(csr_base))
+		return PTR_ERR(csr_base);
+	pdata->mac_csr_addr = csr_base;
+	pdata->mdio_csr_addr = csr_base + BLOCK_XG_MDIO_CSR_OFFSET;
+	pdata->diag_csr_addr = csr_base + BLOCK_DIAG_CSR_OFFSET;
+
+	if (mdio_id == XGENE_MDIO_RGMII)
+		spin_lock_init(&pdata->mac_lock);
+
+	if (dev->of_node) {
+		pdata->clk = devm_clk_get(dev, NULL);
+		if (IS_ERR(pdata->clk)) {
+			dev_err(dev, "Unable to retrieve clk\n");
+			return PTR_ERR(pdata->clk);
+		}
+	}
+
+	ret = xgene_mdio_reset(pdata);
+	if (ret)
+		return ret;
+
+	mdio_bus = mdiobus_alloc();
+	if (!mdio_bus) {
+		ret = -ENOMEM;
+		goto out_clk;
+	}
+
+	mdio_bus->name = "APM X-Gene MDIO bus";
+
+	if (mdio_id == XGENE_MDIO_RGMII) {
+		mdio_bus->read = xgene_mdio_rgmii_read;
+		mdio_bus->write = xgene_mdio_rgmii_write;
+		mdio_bus->priv = (void __force *)pdata;
+		snprintf(mdio_bus->id, MII_BUS_ID_SIZE, "%s",
+			 "xgene-mii-rgmii");
+	} else {
+		mdio_bus->read = xgene_xfi_mdio_read;
+		mdio_bus->write = xgene_xfi_mdio_write;
+		mdio_bus->priv = (void __force *)pdata->mdio_csr_addr;
+		snprintf(mdio_bus->id, MII_BUS_ID_SIZE, "%s",
+			 "xgene-mii-xfi");
+	}
+
+	mdio_bus->parent = dev;
+	platform_set_drvdata(pdev, pdata);
+
+	if (dev->of_node) {
+		ret = of_mdiobus_register(mdio_bus, dev->of_node);
+	} else {
+#ifdef CONFIG_ACPI
+		/* Mask out all PHYs from auto probing. */
+		mdio_bus->phy_mask = ~0;
+		ret = mdiobus_register(mdio_bus);
+		if (ret)
+			goto out_mdiobus;
+
+		acpi_walk_namespace(ACPI_TYPE_DEVICE, ACPI_HANDLE(dev), 1,
+				    acpi_register_phy, NULL, mdio_bus, NULL);
+#endif
+	}
+
+	if (ret)
+		goto out_mdiobus;
+
+	pdata->mdio_bus = mdio_bus;
+	xgene_mdio_status = true;
+
+	return 0;
+
+out_mdiobus:
+	mdiobus_free(mdio_bus);
+
+out_clk:
+	if (dev->of_node)
+		clk_disable_unprepare(pdata->clk);
+
+	return ret;
+}
+
+static int xgene_mdio_remove(struct platform_device *pdev)
+{
+	struct xgene_mdio_pdata *pdata = platform_get_drvdata(pdev);
+	struct mii_bus *mdio_bus = pdata->mdio_bus;
+	struct device *dev = &pdev->dev;
+
+	mdiobus_unregister(mdio_bus);
+	mdiobus_free(mdio_bus);
+
+	if (dev->of_node)
+		clk_disable_unprepare(pdata->clk);
+
+	return 0;
+}
+
+static struct platform_driver xgene_mdio_driver = {
+	.driver = {
+		.name = "xgene-mdio",
+		.of_match_table = of_match_ptr(xgene_mdio_of_match),
+		.acpi_match_table = ACPI_PTR(xgene_mdio_acpi_match),
+	},
+	.probe = xgene_mdio_probe,
+	.remove = xgene_mdio_remove,
+};
+
+module_platform_driver(xgene_mdio_driver);
+
+MODULE_DESCRIPTION("APM X-Gene SoC MDIO driver");
+MODULE_AUTHOR("Iyappan Subramanian <isubramanian@apm.com>");
+MODULE_LICENSE("GPL");