bmips: add experimental ethernet support

This adds experimental ethernet support for BCM6318, BCM6328, BCM6362, BCM6368
and BCM63268.
BCM6358 needs a different driver, so there's no support for now.

Working devices:
- Comtrend AR-5315u
- Comtrend AR-5387un
- Comtrend VR-3025u
- Comtrend VR-3032u

Not working devices:
- Netgear DGND3700 v2 (no idea on how the external switch is connected)
- Huawei HG556a ver B (BCM6358 needs a separate driveer)

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>

5 files changed, 597 insertions, 0 deletions

diff --git a/target/linux/bmips/patches-5.10/500-net-dsa-b53-relax-is63xx-condition.patch b/target/linux/bmips/patches-5.10/500-net-dsa-b53-relax-is63xx-condition.patch
new file mode 100644
index 0000000000..f5dd4e2c59
--- /dev/null
+++ b/target/linux/bmips/patches-5.10/500-net-dsa-b53-relax-is63xx-condition.patch
@@ -0,0 +1,29 @@
+From cd6906754bbe3e0665ecaeca2cfb26d927fe9277 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?=C3=81lvaro=20Fern=C3=A1ndez=20Rojas?= <noltari@gmail.com>
+Date: Mon, 1 Mar 2021 07:29:29 +0100
+Subject: [PATCH 1/3] net: dsa: b53: relax is63xx() condition
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+BCM63xx switches are present on bcm63xx and bmips devices.
+
+Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
+---
+ drivers/net/dsa/b53/b53_priv.h | 4 ----
+ 1 file changed, 4 deletions(-)
+
+--- a/drivers/net/dsa/b53/b53_priv.h
++++ b/drivers/net/dsa/b53/b53_priv.h
+@@ -185,11 +185,7 @@ static inline int is531x5(struct b53_dev
+ 
+ static inline int is63xx(struct b53_device *dev)
+ {
+-#ifdef CONFIG_BCM63XX
+ 	return dev->chip_id == BCM63XX_DEVICE_ID;
+-#else
+-	return 0;
+-#endif
+ }
+ 
+ static inline int is5301x(struct b53_device *dev)
diff --git a/target/linux/bmips/patches-5.10/501-net-dsa-b53-mmap-Add-device-tree-support.patch b/target/linux/bmips/patches-5.10/501-net-dsa-b53-mmap-Add-device-tree-support.patch
new file mode 100644
index 0000000000..e9eb87cb5c
--- /dev/null
+++ b/target/linux/bmips/patches-5.10/501-net-dsa-b53-mmap-Add-device-tree-support.patch
@@ -0,0 +1,82 @@
+From f5419e7f362ae1c462baf28a2da7360267f8e4f9 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?=C3=81lvaro=20Fern=C3=A1ndez=20Rojas?= <noltari@gmail.com>
+Date: Mon, 1 Mar 2021 07:32:32 +0100
+Subject: [PATCH 2/3] net: dsa: b53: mmap: Add device tree support
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Add device tree support to b53_mmap.c while keeping platform devices support.
+
+Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
+---
+ drivers/net/dsa/b53/b53_mmap.c | 36 ++++++++++++++++++++++++++++++++++
+ 1 file changed, 36 insertions(+)
+
+--- a/drivers/net/dsa/b53/b53_mmap.c
++++ b/drivers/net/dsa/b53/b53_mmap.c
+@@ -228,12 +228,64 @@ static const struct b53_io_ops b53_mmap_
+ 	.write64 = b53_mmap_write64,
+ };
+ 
++static int b53_mmap_probe_of(struct platform_device *pdev,
++			     struct b53_platform_data **ppdata)
++{
++	struct device *dev = &pdev->dev;
++	struct device_node *np = dev->of_node;
++	struct device_node *of_ports, *of_port;
++	struct b53_platform_data *pdata;
++	void __iomem *mem;
++
++	mem = devm_platform_ioremap_resource(pdev, 0);
++	if (IS_ERR(mem))
++		return PTR_ERR(mem);
++
++	pdata = devm_kzalloc(dev, sizeof(struct b53_platform_data),
++			     GFP_KERNEL);
++	if (!pdata)
++		return -ENOMEM;
++
++	pdata->regs = mem;
++	pdata->chip_id = BCM63XX_DEVICE_ID;
++	pdata->big_endian = of_property_read_bool(np, "big-endian");
++
++	of_ports = of_get_child_by_name(np, "ports");
++	if (!of_ports) {
++		dev_err(dev, "no ports child node found\n");
++		return -EINVAL;
++	}
++
++	for_each_available_child_of_node(of_ports, of_port) {
++		u32 reg;
++
++		if (of_property_read_u32(of_port, "reg", &reg))
++			continue;
++
++		if (reg < B53_CPU_PORT)
++			pdata->enabled_ports |= BIT(reg);
++	}
++
++	*ppdata = pdata;
++
++	return 0;
++}
++
+ static int b53_mmap_probe(struct platform_device *pdev)
+ {
++	struct device_node *np = pdev->dev.of_node;
+ 	struct b53_platform_data *pdata = pdev->dev.platform_data;
+ 	struct b53_mmap_priv *priv;
+ 	struct b53_device *dev;
+ 
++	if (np) {
++		int ret = b53_mmap_probe_of(pdev, &pdata);
++		if (ret) {
++			dev_err(&pdev->dev, "OF probe error\n");
++			return ret;
++		}
++	}
++
+ 	if (!pdata)
+ 		return -EINVAL;
+ 
diff --git a/target/linux/bmips/patches-5.10/502-net-dsa-b53-support-tags-for-legacy-switches.patch b/target/linux/bmips/patches-5.10/502-net-dsa-b53-support-tags-for-legacy-switches.patch
new file mode 100644
index 0000000000..b8aa8b844d
--- /dev/null
+++ b/target/linux/bmips/patches-5.10/502-net-dsa-b53-support-tags-for-legacy-switches.patch
@@ -0,0 +1,209 @@
+From 3bc3d79efdff6e29b80bf35f7a56baaa36e4d8fe Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?=C3=81lvaro=20Fern=C3=A1ndez=20Rojas?= <noltari@gmail.com>
+Date: Fri, 12 Mar 2021 12:35:39 +0100
+Subject: [PATCH] net: dsa: b53: support tags for legacy switches
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
+---
+ drivers/net/dsa/b53/Kconfig      |  1 +
+ drivers/net/dsa/b53/b53_common.c |  6 +++
+ include/net/dsa.h                |  2 +
+ net/dsa/Kconfig                  |  7 +++
+ net/dsa/tag_brcm.c               | 93 ++++++++++++++++++++++++++++++++
+ 5 files changed, 109 insertions(+)
+
+--- a/drivers/net/dsa/b53/Kconfig
++++ b/drivers/net/dsa/b53/Kconfig
+@@ -3,6 +3,7 @@ menuconfig B53
+ 	tristate "Broadcom BCM53xx managed switch support"
+ 	depends on NET_DSA
+ 	select NET_DSA_TAG_BRCM
++	select NET_DSA_TAG_BRCM_LEGACY
+ 	select NET_DSA_TAG_BRCM_PREPEND
+ 	help
+ 	  This driver adds support for Broadcom managed switch chips. It supports
+--- a/drivers/net/dsa/b53/b53_common.c
++++ b/drivers/net/dsa/b53/b53_common.c
+@@ -1992,6 +1992,7 @@ static bool b53_can_enable_brcm_tags(str
+ 
+ 	switch (tag_protocol) {
+ 	case DSA_TAG_PROTO_BRCM:
++	case DSA_TAG_PROTO_BRCM_LEGACY:
+ 	case DSA_TAG_PROTO_BRCM_PREPEND:
+ 		dev_warn(ds->dev,
+ 			 "Port %d is stacked to Broadcom tag switch\n", port);
+@@ -2013,12 +2014,16 @@ enum dsa_tag_protocol b53_get_tag_protoc
+ 	/* Older models (5325, 5365) support a different tag format that we do
+ 	 * not support in net/dsa/tag_brcm.c yet.
+ 	 */
+-	if (is5325(dev) || is5365(dev) ||
+-	    !b53_can_enable_brcm_tags(ds, port, mprot)) {
++	if (!b53_can_enable_brcm_tags(ds, port, mprot)) {
+ 		dev->tag_protocol = DSA_TAG_PROTO_NONE;
+ 		goto out;
+ 	}
+ 
++	if (is5325(dev) || is5365(dev) || is63xx(dev)) {
++		dev->tag_protocol = DSA_TAG_PROTO_BRCM_LEGACY;
++		goto out;
++	}
++
+ 	/* Broadcom BCM58xx chips have a flow accelerator on Port 8
+ 	 * which requires us to use the prepended Broadcom tag type
+ 	 */
+--- a/include/net/dsa.h
++++ b/include/net/dsa.h
+@@ -45,10 +45,12 @@ struct phylink_link_state;
+ #define DSA_TAG_PROTO_OCELOT_VALUE		15
+ #define DSA_TAG_PROTO_AR9331_VALUE		16
+ #define DSA_TAG_PROTO_RTL4_A_VALUE		17
++#define DSA_TAG_PROTO_BRCM_LEGACY_VALUE		22
+ 
+ enum dsa_tag_protocol {
+ 	DSA_TAG_PROTO_NONE		= DSA_TAG_PROTO_NONE_VALUE,
+ 	DSA_TAG_PROTO_BRCM		= DSA_TAG_PROTO_BRCM_VALUE,
++	DSA_TAG_PROTO_BRCM_LEGACY	= DSA_TAG_PROTO_BRCM_LEGACY_VALUE,
+ 	DSA_TAG_PROTO_BRCM_PREPEND	= DSA_TAG_PROTO_BRCM_PREPEND_VALUE,
+ 	DSA_TAG_PROTO_DSA		= DSA_TAG_PROTO_DSA_VALUE,
+ 	DSA_TAG_PROTO_EDSA		= DSA_TAG_PROTO_EDSA_VALUE,
+--- a/net/dsa/Kconfig
++++ b/net/dsa/Kconfig
+@@ -47,6 +47,13 @@ config NET_DSA_TAG_BRCM
+ 	  Say Y if you want to enable support for tagging frames for the
+ 	  Broadcom switches which place the tag after the MAC source address.
+ 
++config NET_DSA_TAG_BRCM_LEGACY
++	tristate "Tag driver for Broadcom legacy switches using in-frame headers"
++	select NET_DSA_TAG_BRCM_COMMON
++	help
++	  Say Y if you want to enable support for tagging frames for the
++	  Broadcom legacy switches which place the tag after the MAC source
++	  address.
+ 
+ config NET_DSA_TAG_BRCM_PREPEND
+ 	tristate "Tag driver for Broadcom switches using prepended headers"
+--- a/net/dsa/tag_brcm.c
++++ b/net/dsa/tag_brcm.c
+@@ -8,9 +8,23 @@
+ #include <linux/etherdevice.h>
+ #include <linux/list.h>
+ #include <linux/slab.h>
++#include <linux/types.h>
+ 
+ #include "dsa_priv.h"
+ 
++struct bcm_legacy_tag {
++	uint16_t type;
++#define BRCM_LEG_TYPE	0x8874
++
++	uint32_t tag;
++#define BRCM_LEG_TAG_PORT_ID	(0xf)
++#define BRCM_LEG_TAG_MULTICAST	(1 << 29)
++#define BRCM_LEG_TAG_EGRESS	(2 << 29)
++#define BRCM_LEG_TAG_INGRESS	(3 << 29)
++} __attribute__((packed));
++
++#define BRCM_LEG_TAG_LEN	sizeof(struct bcm_legacy_tag)
++
+ /* This tag length is 4 bytes, older ones were 6 bytes, we do not
+  * handle them
+  */
+@@ -197,6 +211,85 @@ DSA_TAG_DRIVER(brcm_netdev_ops);
+ MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_BRCM);
+ #endif
+ 
++#if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_LEGACY)
++static struct sk_buff *brcm_leg_tag_xmit(struct sk_buff *skb,
++					 struct net_device *dev)
++{
++	struct dsa_port *dp = dsa_slave_to_port(dev);
++	struct bcm_legacy_tag *brcm_tag;
++
++	if (skb_cow_head(skb, BRCM_LEG_TAG_LEN) < 0)
++		return NULL;
++
++	/* The Ethernet switch we are interfaced with needs packets to be at
++	 * least 64 bytes (including FCS) otherwise they will be discarded when
++	 * they enter the switch port logic. When Broadcom tags are enabled, we
++	 * need to make sure that packets are at least 70 bytes
++	 * (including FCS and tag) because the length verification is done after
++	 * the Broadcom tag is stripped off the ingress packet.
++	 *
++	 * Let dsa_slave_xmit() free the SKB
++	 */
++	if (__skb_put_padto(skb, ETH_ZLEN + BRCM_LEG_TAG_LEN, false))
++		return NULL;
++
++	skb_push(skb, BRCM_LEG_TAG_LEN);
++
++	memmove(skb->data, skb->data + BRCM_LEG_TAG_LEN, 2 * ETH_ALEN);
++
++	brcm_tag = (struct bcm_legacy_tag *) (skb->data + 2 * ETH_ALEN);
++
++	brcm_tag->type = BRCM_LEG_TYPE;
++	brcm_tag->tag = BRCM_LEG_TAG_EGRESS;
++	brcm_tag->tag |= dp->index & BRCM_LEG_TAG_PORT_ID;
++
++	return skb;
++}
++
++
++static struct sk_buff *brcm_leg_tag_rcv(struct sk_buff *skb,
++					struct net_device *dev,
++					struct packet_type *pt)
++{
++	int source_port;
++	struct bcm_legacy_tag *brcm_tag;
++
++	if (unlikely(!pskb_may_pull(skb, BRCM_LEG_TAG_LEN)))
++		return NULL;
++
++	brcm_tag = (struct bcm_legacy_tag *) (skb->data - 2);
++
++	source_port = brcm_tag->tag & BRCM_LEG_TAG_PORT_ID;
++
++	skb->dev = dsa_master_find_slave(dev, 0, source_port);
++	if (!skb->dev)
++		return NULL;
++
++	/* Remove Broadcom tag and update checksum */
++	skb_pull_rcsum(skb, BRCM_LEG_TAG_LEN);
++
++	skb->offload_fwd_mark = 1;
++
++	/* Move the Ethernet DA and SA */
++	memmove(skb->data - ETH_HLEN,
++		skb->data - ETH_HLEN - BRCM_LEG_TAG_LEN,
++		2 * ETH_ALEN);
++
++	return skb;
++}
++
++static const struct dsa_device_ops brcm_legacy_netdev_ops = {
++	.name	= "brcm-legacy",
++	.proto	= DSA_TAG_PROTO_BRCM_LEGACY,
++	.xmit	= brcm_leg_tag_xmit,
++	.rcv	= brcm_leg_tag_rcv,
++	.overhead = BRCM_LEG_TAG_LEN,
++};
++
++DSA_TAG_DRIVER(brcm_legacy_netdev_ops);
++MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_BRCM_LEGACY);
++#endif /* CONFIG_NET_DSA_TAG_BRCM_LEGACY */
++
+ #if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_PREPEND)
+ static struct sk_buff *brcm_tag_xmit_prepend(struct sk_buff *skb,
+ 					     struct net_device *dev)
+@@ -229,6 +322,9 @@ static struct dsa_tag_driver *dsa_tag_dr
+ #if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM)
+ 	&DSA_TAG_DRIVER_NAME(brcm_netdev_ops),
+ #endif
++#if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_LEGACY)
++	&DSA_TAG_DRIVER_NAME(brcm_legacy_netdev_ops),
++#endif
+ #if IS_ENABLED(CONFIG_NET_DSA_TAG_BRCM_PREPEND)
+ 	&DSA_TAG_DRIVER_NAME(brcm_prepend_netdev_ops),
+ #endif
diff --git a/target/linux/bmips/patches-5.10/503-net-broadcom-add-BCM6368-enetsw-controller-driver.patch b/target/linux/bmips/patches-5.10/503-net-broadcom-add-BCM6368-enetsw-controller-driver.patch
new file mode 100644
index 0000000000..c2c2e968e9
--- /dev/null
+++ b/target/linux/bmips/patches-5.10/503-net-broadcom-add-BCM6368-enetsw-controller-driver.patch
@@ -0,0 +1,46 @@
+From 590b60fb08cb1e70fe02d3f407c6b3dbe9ad06ff Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?=C3=81lvaro=20Fern=C3=A1ndez=20Rojas?= <noltari@gmail.com>
+Date: Mon, 1 Mar 2021 07:34:39 +0100
+Subject: [PATCH 3/4] net: broadcom: add BCM6368 enetsw controller driver
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+This controller is present on BCM6318, BCM6328, BCM6362, BCM6368 and BCM63268
+SoCs.
+
+Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
+---
+ drivers/net/ethernet/broadcom/Kconfig         |    8 +
+ drivers/net/ethernet/broadcom/Makefile        |    1 +
+ .../net/ethernet/broadcom/bcm6368-enetsw.c    | 1111 +++++++++++++++++
+ 3 files changed, 1120 insertions(+)
+ create mode 100644 drivers/net/ethernet/broadcom/bcm6368-enetsw.c
+
+--- a/drivers/net/ethernet/broadcom/Kconfig
++++ b/drivers/net/ethernet/broadcom/Kconfig
+@@ -60,6 +60,14 @@ config BCM63XX_ENET
+ 	  This driver supports the ethernet MACs in the Broadcom 63xx
+ 	  MIPS chipset family (BCM63XX).
+ 
++config BCM6368_ENETSW
++	tristate "Broadcom BCM6368 internal mac support"
++	depends on BMIPS_GENERIC || COMPILE_TEST
++	default y
++	help
++	  This driver supports Ethernet controller integrated into Broadcom
++	  BCM6368 family SoCs.
++
+ config BCMGENET
+ 	tristate "Broadcom GENET internal MAC support"
+ 	depends on HAS_IOMEM
+--- a/drivers/net/ethernet/broadcom/Makefile
++++ b/drivers/net/ethernet/broadcom/Makefile
+@@ -5,6 +5,7 @@
+ 
+ obj-$(CONFIG_B44) += b44.o
+ obj-$(CONFIG_BCM63XX_ENET) += bcm63xx_enet.o
++obj-$(CONFIG_BCM6368_ENETSW) += bcm6368-enetsw.o
+ obj-$(CONFIG_BCMGENET) += genet/
+ obj-$(CONFIG_BNX2) += bnx2.o
+ obj-$(CONFIG_CNIC) += cnic.o
diff --git a/target/linux/bmips/patches-5.10/504-net-mdio-Add-BCM6368-MDIO-mux-bus-controller.patch b/target/linux/bmips/patches-5.10/504-net-mdio-Add-BCM6368-MDIO-mux-bus-controller.patch
new file mode 100644
index 0000000000..a869681312
--- /dev/null
+++ b/target/linux/bmips/patches-5.10/504-net-mdio-Add-BCM6368-MDIO-mux-bus-controller.patch
@@ -0,0 +1,231 @@
+From b6ecb2bca2b8ff80ae4b1b15f09dcf071f4ceaf4 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?=C3=81lvaro=20Fern=C3=A1ndez=20Rojas?= <noltari@gmail.com>
+Date: Mon, 1 Mar 2021 16:42:12 +0100
+Subject: [PATCH] net: mdio: Add BCM6368 MDIO mux bus controller
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+This controller is present on BCM6318, BCM6328, BCM6362, BCM6368 and BCM63268
+SoCs.
+
+Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
+---
+ drivers/net/mdio/Kconfig            |  11 ++
+ drivers/net/mdio/Makefile           |   1 +
+ drivers/net/mdio/mdio-mux-bcm6368.c | 179 ++++++++++++++++++++++++++++
+ 3 files changed, 191 insertions(+)
+ create mode 100644 drivers/net/mdio/mdio-mux-bcm6368.c
+
+--- a/drivers/net/mdio/Kconfig
++++ b/drivers/net/mdio/Kconfig
+@@ -200,6 +200,17 @@ config MDIO_BUS_MUX_MESON_G12A
+ 	  the amlogic g12a SoC. The multiplexers connects either the external
+ 	  or the internal MDIO bus to the parent bus.
+ 
++config MDIO_BUS_MUX_BCM6368
++	tristate "Broadcom BCM6368 MDIO bus multiplexers"
++	depends on OF && OF_MDIO && (BMIPS_GENERIC || COMPILE_TEST)
++	select MDIO_BUS_MUX
++	default BMIPS_GENERIC
++	help
++	  This module provides a driver for MDIO bus multiplexers found in
++	  BCM6368 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_BCM_IPROC
+ 	tristate "Broadcom iProc based MDIO bus multiplexers"
+ 	depends on OF && OF_MDIO && (ARCH_BCM_IPROC || COMPILE_TEST)
+--- a/drivers/net/mdio/Makefile
++++ b/drivers/net/mdio/Makefile
+@@ -22,6 +22,7 @@ obj-$(CONFIG_MDIO_THUNDER)		+= mdio-thun
+ obj-$(CONFIG_MDIO_XGENE)		+= mdio-xgene.o
+ 
+ obj-$(CONFIG_MDIO_BUS_MUX)		+= mdio-mux.o
++obj-$(CONFIG_MDIO_BUS_MUX_BCM6368)	+= mdio-mux-bcm6368.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
+--- /dev/null
++++ b/drivers/net/mdio/mdio-mux-bcm6368.c
+@@ -0,0 +1,179 @@
++// SPDX-License-Identifier: GPL-2.0+
++/*
++ * Broadcom BCM6368 mdiomux bus controller driver
++ *
++ * Copyright (C) 2021 Álvaro Fernández Rojas <noltari@gmail.com>
++ */
++
++#include <linux/delay.h>
++#include <linux/io.h>
++#include <linux/kernel.h>
++#include <linux/mdio-mux.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 MDIOC_REG		0x0
++#define MDIOC_EXT_MASK		BIT(16)
++#define MDIOC_REG_SHIFT		20
++#define MDIOC_PHYID_SHIFT	25
++#define MDIOC_RD_MASK		BIT(30)
++#define MDIOC_WR_MASK		BIT(31)
++
++#define MDIOD_REG		0x4
++
++struct bcm6368_mdiomux_desc {
++	void *mux_handle;
++	void __iomem *base;
++	struct device *dev;
++	struct mii_bus *mii_bus;
++	int ext_phy;
++};
++
++static int bcm6368_mdiomux_read(struct mii_bus *bus, int phy_id, int loc)
++{
++	struct bcm6368_mdiomux_desc *md = bus->priv;
++	uint32_t reg;
++	int ret;
++
++	__raw_writel(0, md->base + MDIOC_REG);
++
++	reg = MDIOC_RD_MASK |
++	      (phy_id << MDIOC_PHYID_SHIFT) |
++	      (loc << MDIOC_REG_SHIFT);
++	if (md->ext_phy)
++		reg |= MDIOC_EXT_MASK;
++
++	__raw_writel(reg, md->base + MDIOC_REG);
++	udelay(50);
++	ret = __raw_readw(md->base + MDIOD_REG);
++
++	return ret;
++}
++
++static int bcm6368_mdiomux_write(struct mii_bus *bus, int phy_id, int loc,
++				 uint16_t val)
++{
++	struct bcm6368_mdiomux_desc *md = bus->priv;
++	uint32_t reg;
++
++	__raw_writel(0, md->base + MDIOC_REG);
++
++	reg = MDIOC_WR_MASK |
++	      (phy_id << MDIOC_PHYID_SHIFT) |
++	      (loc << MDIOC_REG_SHIFT);
++	if (md->ext_phy)
++		reg |= MDIOC_EXT_MASK;
++	reg |= val;
++
++	__raw_writel(reg, md->base + MDIOC_REG);
++	udelay(50);
++
++	return 0;
++}
++
++static int bcm6368_mdiomux_switch_fn(int current_child, int desired_child,
++				     void *data)
++{
++	struct bcm6368_mdiomux_desc *md = data;
++
++	md->ext_phy = desired_child;
++
++	return 0;
++}
++
++static int bcm6368_mdiomux_probe(struct platform_device *pdev)
++{
++	struct bcm6368_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)
++		return -EINVAL;
++
++	/* Just ioremap, as this MDIO block is usually integrated into an
++	 * Ethernet MAC controller register range
++	 */
++	md->base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
++	if (!md->base) {
++		dev_err(&pdev->dev, "failed to ioremap register\n");
++		return -ENOMEM;
++	}
++
++	md->mii_bus = devm_mdiobus_alloc(&pdev->dev);
++	if (!md->mii_bus) {
++		dev_err(&pdev->dev, "mdiomux bus alloc failed\n");
++		return ENOMEM;
++	}
++
++	bus = md->mii_bus;
++	bus->priv = md;
++	bus->name = "BCM6368 MDIO mux bus";
++	snprintf(bus->id, MII_BUS_ID_SIZE, "%s-%d", pdev->name, pdev->id);
++	bus->parent = &pdev->dev;
++	bus->read = bcm6368_mdiomux_read;
++	bus->write = bcm6368_mdiomux_write;
++	bus->phy_mask = 0x3f;
++	bus->dev.of_node = pdev->dev.of_node;
++
++	rc = mdiobus_register(bus);
++	if (rc) {
++		dev_err(&pdev->dev, "mdiomux registration failed\n");
++		return rc;
++	}
++
++	platform_set_drvdata(pdev, md);
++
++	rc = mdio_mux_init(md->dev, md->dev->of_node,
++			   bcm6368_mdiomux_switch_fn, &md->mux_handle, md,
++			   md->mii_bus);
++	if (rc) {
++		dev_info(md->dev, "mdiomux initialization failed\n");
++		goto out_register;
++	}
++
++	dev_info(&pdev->dev, "Broadcom BCM6368 MDIO mux bus\n");
++
++	return 0;
++
++out_register:
++	mdiobus_unregister(bus);
++	return rc;
++}
++
++static int bcm6368_mdiomux_remove(struct platform_device *pdev)
++{
++	struct bcm6368_mdiomux_desc *md = platform_get_drvdata(pdev);
++
++	mdio_mux_uninit(md->mux_handle);
++	mdiobus_unregister(md->mii_bus);
++
++	return 0;
++}
++
++static const struct of_device_id bcm6368_mdiomux_ids[] = {
++	{ .compatible = "brcm,bcm6368-mdio-mux", },
++	{ /* sentinel */ }
++};
++MODULE_DEVICE_TABLE(of, bcm6368_mdiomux_ids);
++
++static struct platform_driver bcm6368_mdiomux_driver = {
++	.driver = {
++		.name = "bcm6368-mdio-mux",
++		.of_match_table = bcm6368_mdiomux_ids,
++	},
++	.probe	= bcm6368_mdiomux_probe,
++	.remove	= bcm6368_mdiomux_remove,
++};
++module_platform_driver(bcm6368_mdiomux_driver);