Merge branch 'dsa-add-Microchip-KSZ9477-DSA-driver'

Woojung Huh says:

====================
dsa: add Microchip KSZ9477 DSA driver

This series of patches is for Microchip KSZ9477 DSA driver.
KSZ9477 is 7 ports GigE switch with numerous advanced features.
5 ports are 10/100/1000 Mbps internal PHYs and 2 ports have
Interfaces to SGMII, RGMII, MII or RMII.

This patch supports VLAN, MDB, FDB and port mirroring offloads.

Welcome reviews and comments from community.

Note: Tests are performed on internal development board.

V5
- add missing MODULE_LICENSE

V4
- update per review comments
- cosmetic changes
- net/dsa/tag_ksz.c
  * skb_put() & memset() are changed to skb_put_padto()
- drivers/net/dsa/microchip/ksz_common.
   * vlan access mutex is updated
   * mib_names[] is changed to static const

V3
- update per review comments
- cosmetic changes
- drivers/net/dsa/microchip/ksz_common.c
  * clean up ksz_switch_chips[]
  * consolidate checking loops into functions
  * update mutex for better locking
  * replace devm_kmalloc_array() to devm_kcalloc()
- MAINTAINERS
  * add missing net/dsa/tag_ksz.c

V2
- update per review comments
- several cosmetic changes
- net/dsa/tag_ksz.c
  * constants are changed to defines
  * remove skb_linearize() in ksz_rcv()
  * ksz_xmit()checks skb tailroom before allocate new skb
- drivers/net/phy/micrel.c
  * remove PHY_HAS_MAGICANEG from ksphy_driver[]
- drivers/net/dsa/microchip/ksz_common.c
  * add timeout to avoid endless loop
  * port initialization is move to ksz_port_enable() instead of  ksz_setup_ports()
- Documentation/devicetree/bindings/net/dsa/ksz.txt
  * fix typo and indentations
====================
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Documentation/devicetree/bindings/net/dsa/ksz.txt

+Microchip KSZ Series Ethernet switches
+==================================
+
+Required properties:
+
+- compatible: For external switch chips, compatible string must be exactly one
+  of: "microchip,ksz9477"
+
+See Documentation/devicetree/bindings/dsa/dsa.txt for a list of additional
+required and optional properties.
+
+Examples:
+
+Ethernet switch connected via SPI to the host, CPU port wired to eth0:
+
+                             eth0: ethernet@10001000 {
+                                             fixed-link {
+                                                             speed = <1000>;
+                                                             full-duplex;
+                                             };
+                             };
+
+                             spi1: spi@f8008000 {
+                                             pinctrl-0 = <&pinctrl_spi_ksz>;
+                                             cs-gpios = <&pioC 25 0>;
+                                             id = <1>;
+                                             status = "okay";
+
+                                             ksz9477: ksz9477@0 {
+                                                             compatible = "microchip,ksz9477";
+                                                             reg = <0>;
+
+                                                             spi-max-frequency = <44000000>;
+                                                             spi-cpha;
+                                                             spi-cpol;
+
+                                                             status = "okay";
+                                                             ports {
+                                                                             #address-cells = <1>;
+                                                                             #size-cells = <0>;
+                                                                             port@0 {
+                                                                                             reg = <0>;
+                                                                                             label = "lan1";
+                                                                             };
+                                                                             port@1 {
+                                                                                             reg = <1>;
+                                                                                             label = "lan2";
+                                                                             };
+                                                                             port@2 {
+                                                                                             reg = <2>;
+                                                                                             label = "lan3";
+                                                                             };
+                                                                             port@3 {
+                                                                                             reg = <3>;
+                                                                                             label = "lan4";
+                                                                             };
+                                                                             port@4 {
+                                                                                             reg = <4>;
+                                                                                             label = "lan5";
+                                                                             };
+                                                                             port@5 {
+                                                                                             reg = <5>;
+                                                                                             label = "cpu";
+                                                                                             ethernet = <&eth0>;
+                                                                                             fixed-link {
+                                                                                                             speed = <1000>;
+                                                                                                             full-duplex;
+                                                                                             };
+                                                                             };
+                                                             };
+                                             };
+                             };

MAINTAINERS

@@ -8479,6 +8479,16 @@ F:	drivers/media/platform/atmel/atmel-isc.c
 F:	drivers/media/platform/atmel/atmel-isc-regs.h
 F:	devicetree/bindings/media/atmel-isc.txt
 
+MICROCHIP KSZ SERIES ETHERNET SWITCH DRIVER
+M:	Woojung Huh <Woojung.Huh@microchip.com>
+M:	Microchip Linux Driver Support <UNGLinuxDriver@microchip.com>
+L:	netdev@vger.kernel.org
+S:	Maintained
+F:	net/dsa/tag_ksz.c
+F:	drivers/net/dsa/microchip/*
+F:	include/linux/platform_data/microchip-ksz.h
+F:	Documentation/devicetree/bindings/net/dsa/ksz.txt
+
 MICROCHIP USB251XB DRIVER
 M:	Richard Leitner <richard.leitner@skidata.com>
 L:	linux-usb@vger.kernel.org

drivers/net/dsa/Kconfig

@@ -39,6 +39,8 @@ config NET_DSA_MV88E6060
 	  This enables support for the Marvell 88E6060 ethernet switch
 	  chip.
 
+source "drivers/net/dsa/microchip/Kconfig"
+
 source "drivers/net/dsa/mv88e6xxx/Kconfig"
 
 config NET_DSA_QCA8K

drivers/net/dsa/Makefile

@@ -8,4 +8,5 @@ obj-$(CONFIG_NET_DSA_SMSC_LAN9303) += lan9303-core.o
 obj-$(CONFIG_NET_DSA_SMSC_LAN9303_I2C) += lan9303_i2c.o
 obj-$(CONFIG_NET_DSA_SMSC_LAN9303_MDIO) += lan9303_mdio.o
 obj-y				+= b53/
+obj-y				+= microchip/
 obj-y				+= mv88e6xxx/

drivers/net/dsa/microchip/Kconfig

+menuconfig MICROCHIP_KSZ
+	tristate "Microchip KSZ series switch support"
+	depends on NET_DSA
+	select NET_DSA_TAG_KSZ
+	help
+	  This driver adds support for Microchip KSZ switch chips.
+
+config MICROCHIP_KSZ_SPI_DRIVER
+	tristate "KSZ series SPI connected switch driver"
+	depends on MICROCHIP_KSZ && SPI
+	help
+	  Select to enable support for registering switches configured through SPI.

drivers/net/dsa/microchip/Makefile

+obj-$(CONFIG_MICROCHIP_KSZ)	        += ksz_common.o
+obj-$(CONFIG_MICROCHIP_KSZ_SPI_DRIVER)	+= ksz_spi.o

drivers/net/dsa/microchip/ksz_priv.h

+/*
+ * Microchip KSZ series switch common definitions
+ *
+ * Copyright (C) 2017
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#ifndef __KSZ_PRIV_H
+#define __KSZ_PRIV_H
+
+#include <linux/kernel.h>
+#include <linux/mutex.h>
+#include <linux/phy.h>
+#include <linux/etherdevice.h>
+#include <net/dsa.h>
+
+#include "ksz_9477_reg.h"
+
+struct ksz_io_ops;
+
+struct vlan_table {
+	u32 table[3];
+};
+
+struct ksz_device {
+	struct dsa_switch *ds;
+	struct ksz_platform_data *pdata;
+	const char *name;
+
+	struct mutex reg_mutex;		/* register access */
+	struct mutex stats_mutex;	/* status access */
+	struct mutex alu_mutex;		/* ALU access */
+	struct mutex vlan_mutex;	/* vlan access */
+	const struct ksz_io_ops *ops;
+
+	struct device *dev;
+
+	void *priv;
+
+	/* chip specific data */
+	u32 chip_id;
+	int num_vlans;
+	int num_alus;
+	int num_statics;
+	int cpu_port;			/* port connected to CPU */
+	int cpu_ports;			/* port bitmap can be cpu port */
+	int port_cnt;
+
+	struct vlan_table *vlan_cache;
+
+	u64 mib_value[TOTAL_SWITCH_COUNTER_NUM];
+};
+
+struct ksz_io_ops {
+	int (*read8)(struct ksz_device *dev, u32 reg, u8 *value);
+	int (*read16)(struct ksz_device *dev, u32 reg, u16 *value);
+	int (*read24)(struct ksz_device *dev, u32 reg, u32 *value);
+	int (*read32)(struct ksz_device *dev, u32 reg, u32 *value);
+	int (*write8)(struct ksz_device *dev, u32 reg, u8 value);
+	int (*write16)(struct ksz_device *dev, u32 reg, u16 value);
+	int (*write24)(struct ksz_device *dev, u32 reg, u32 value);
+	int (*write32)(struct ksz_device *dev, u32 reg, u32 value);
+	int (*phy_read16)(struct ksz_device *dev, int addr, int reg,
+			  u16 *value);
+	int (*phy_write16)(struct ksz_device *dev, int addr, int reg,
+			   u16 value);
+};
+
+struct ksz_device *ksz_switch_alloc(struct device *base,
+				    const struct ksz_io_ops *ops, void *priv);
+int ksz_switch_detect(struct ksz_device *dev);
+int ksz_switch_register(struct ksz_device *dev);
+void ksz_switch_remove(struct ksz_device *dev);
+
+static inline int ksz_read8(struct ksz_device *dev, u32 reg, u8 *val)
+{
+	int ret;
+
+	mutex_lock(&dev->reg_mutex);
+	ret = dev->ops->read8(dev, reg, val);
+	mutex_unlock(&dev->reg_mutex);
+
+	return ret;
+}
+
+static inline int ksz_read16(struct ksz_device *dev, u32 reg, u16 *val)
+{
+	int ret;
+
+	mutex_lock(&dev->reg_mutex);
+	ret = dev->ops->read16(dev, reg, val);
+	mutex_unlock(&dev->reg_mutex);
+
+	return ret;
+}
+
+static inline int ksz_read24(struct ksz_device *dev, u32 reg, u32 *val)
+{
+	int ret;
+
+	mutex_lock(&dev->reg_mutex);
+	ret = dev->ops->read24(dev, reg, val);
+	mutex_unlock(&dev->reg_mutex);
+
+	return ret;
+}
+
+static inline int ksz_read32(struct ksz_device *dev, u32 reg, u32 *val)
+{
+	int ret;
+
+	mutex_lock(&dev->reg_mutex);
+	ret = dev->ops->read32(dev, reg, val);
+	mutex_unlock(&dev->reg_mutex);
+
+	return ret;
+}
+
+static inline int ksz_write8(struct ksz_device *dev, u32 reg, u8 value)
+{
+	int ret;
+
+	mutex_lock(&dev->reg_mutex);
+	ret = dev->ops->write8(dev, reg, value);
+	mutex_unlock(&dev->reg_mutex);
+
+	return ret;
+}
+
+static inline int ksz_write16(struct ksz_device *dev, u32 reg, u16 value)
+{
+	int ret;
+
+	mutex_lock(&dev->reg_mutex);
+	ret = dev->ops->write16(dev, reg, value);
+	mutex_unlock(&dev->reg_mutex);
+
+	return ret;
+}
+
+static inline int ksz_write24(struct ksz_device *dev, u32 reg, u32 value)
+{
+	int ret;
+
+	mutex_lock(&dev->reg_mutex);
+	ret = dev->ops->write24(dev, reg, value);
+	mutex_unlock(&dev->reg_mutex);
+
+	return ret;
+}
+
+static inline int ksz_write32(struct ksz_device *dev, u32 reg, u32 value)
+{
+	int ret;
+
+	mutex_lock(&dev->reg_mutex);
+	ret = dev->ops->write32(dev, reg, value);
+	mutex_unlock(&dev->reg_mutex);
+
+	return ret;
+}
+
+static inline void ksz_pread8(struct ksz_device *dev, int port, int offset,
+			      u8 *data)
+{
+	ksz_read8(dev, PORT_CTRL_ADDR(port, offset), data);
+}
+
+static inline void ksz_pread16(struct ksz_device *dev, int port, int offset,
+			       u16 *data)
+{
+	ksz_read16(dev, PORT_CTRL_ADDR(port, offset), data);
+}
+
+static inline void ksz_pread32(struct ksz_device *dev, int port, int offset,
+			       u32 *data)
+{
+	ksz_read32(dev, PORT_CTRL_ADDR(port, offset), data);
+}
+
+static inline void ksz_pwrite8(struct ksz_device *dev, int port, int offset,
+			       u8 data)
+{
+	ksz_write8(dev, PORT_CTRL_ADDR(port, offset), data);
+}
+
+static inline void ksz_pwrite16(struct ksz_device *dev, int port, int offset,
+				u16 data)
+{
+	ksz_write16(dev, PORT_CTRL_ADDR(port, offset), data);
+}
+
+static inline void ksz_pwrite32(struct ksz_device *dev, int port, int offset,
+				u32 data)
+{
+	ksz_write32(dev, PORT_CTRL_ADDR(port, offset), data);
+}
+
+#endif

drivers/net/dsa/microchip/ksz_spi.c

+/*
+ * Microchip KSZ series register access through SPI
+ *
+ * Copyright (C) 2017
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <asm/unaligned.h>
+
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/spi/spi.h>
+
+#include "ksz_priv.h"
+
+/* SPI frame opcodes */
+#define KS_SPIOP_RD			3
+#define KS_SPIOP_WR			2
+
+#define SPI_ADDR_SHIFT			24
+#define SPI_ADDR_MASK			(BIT(SPI_ADDR_SHIFT) - 1)
+#define SPI_TURNAROUND_SHIFT		5
+
+static int ksz_spi_read_reg(struct spi_device *spi, u32 reg, u8 *val,
+			    unsigned int len)
+{
+	u32 txbuf;
+	int ret;
+
+	txbuf = reg & SPI_ADDR_MASK;
+	txbuf |= KS_SPIOP_RD << SPI_ADDR_SHIFT;
+	txbuf <<= SPI_TURNAROUND_SHIFT;
+	txbuf = cpu_to_be32(txbuf);
+
+	ret = spi_write_then_read(spi, &txbuf, 4, val, len);
+	return ret;
+}
+
+static int ksz_spi_read(struct ksz_device *dev, u32 reg, u8 *data,
+			unsigned int len)
+{
+	struct spi_device *spi = dev->priv;
+
+	return ksz_spi_read_reg(spi, reg, data, len);
+}
+
+static int ksz_spi_read8(struct ksz_device *dev, u32 reg, u8 *val)
+{
+	return ksz_spi_read(dev, reg, val, 1);
+}
+
+static int ksz_spi_read16(struct ksz_device *dev, u32 reg, u16 *val)
+{
+	int ret = ksz_spi_read(dev, reg, (u8 *)val, 2);
+
+	if (!ret)
+		*val = be16_to_cpu(*val);
+
+	return ret;
+}
+
+static int ksz_spi_read24(struct ksz_device *dev, u32 reg, u32 *val)
+{
+	int ret;
+
+	*val = 0;
+	ret = ksz_spi_read(dev, reg, (u8 *)val, 3);
+	if (!ret) {
+		*val = be32_to_cpu(*val);
+		/* convert to 24bit */
+		*val >>= 8;
+	}
+
+	return ret;
+}
+
+static int ksz_spi_read32(struct ksz_device *dev, u32 reg, u32 *val)
+{
+	int ret = ksz_spi_read(dev, reg, (u8 *)val, 4);
+
+	if (!ret)
+		*val = be32_to_cpu(*val);
+
+	return ret;
+}
+
+static int ksz_spi_write_reg(struct spi_device *spi, u32 reg, u8 *val,
+			     unsigned int len)
+{
+	u32 txbuf;
+	u8 data[12];
+	int i;
+
+	txbuf = reg & SPI_ADDR_MASK;
+	txbuf |= (KS_SPIOP_WR << SPI_ADDR_SHIFT);
+	txbuf <<= SPI_TURNAROUND_SHIFT;
+	txbuf = cpu_to_be32(txbuf);
+
+	data[0] = txbuf & 0xFF;
+	data[1] = (txbuf & 0xFF00) >> 8;
+	data[2] = (txbuf & 0xFF0000) >> 16;
+	data[3] = (txbuf & 0xFF000000) >> 24;
+	for (i = 0; i < len; i++)
+		data[i + 4] = val[i];
+
+	return spi_write(spi, &data, 4 + len);
+}
+
+static int ksz_spi_write8(struct ksz_device *dev, u32 reg, u8 value)
+{
+	struct spi_device *spi = dev->priv;
+
+	return ksz_spi_write_reg(spi, reg, &value, 1);
+}
+
+static int ksz_spi_write16(struct ksz_device *dev, u32 reg, u16 value)
+{
+	struct spi_device *spi = dev->priv;
+
+	value = cpu_to_be16(value);
+	return ksz_spi_write_reg(spi, reg, (u8 *)&value, 2);
+}
+
+static int ksz_spi_write24(struct ksz_device *dev, u32 reg, u32 value)
+{
+	struct spi_device *spi = dev->priv;
+
+	/* make it to big endian 24bit from MSB */
+	value <<= 8;
+	value = cpu_to_be32(value);
+	return ksz_spi_write_reg(spi, reg, (u8 *)&value, 3);
+}
+
+static int ksz_spi_write32(struct ksz_device *dev, u32 reg, u32 value)
+{
+	struct spi_device *spi = dev->priv;
+
+	value = cpu_to_be32(value);
+	return ksz_spi_write_reg(spi, reg, (u8 *)&value, 4);
+}
+
+static const struct ksz_io_ops ksz_spi_ops = {
+	.read8 = ksz_spi_read8,
+	.read16 = ksz_spi_read16,
+	.read24 = ksz_spi_read24,
+	.read32 = ksz_spi_read32,
+	.write8 = ksz_spi_write8,
+	.write16 = ksz_spi_write16,
+	.write24 = ksz_spi_write24,
+	.write32 = ksz_spi_write32,
+};
+
+static int ksz_spi_probe(struct spi_device *spi)
+{
+	struct ksz_device *dev;
+	int ret;
+
+	dev = ksz_switch_alloc(&spi->dev, &ksz_spi_ops, spi);
+	if (!dev)
+		return -ENOMEM;
+
+	if (spi->dev.platform_data)
+		dev->pdata = spi->dev.platform_data;
+
+	ret = ksz_switch_register(dev);
+	if (ret)
+		return ret;
+
+	spi_set_drvdata(spi, dev);
+
+	return 0;
+}
+
+static int ksz_spi_remove(struct spi_device *spi)
+{
+	struct ksz_device *dev = spi_get_drvdata(spi);
+
+	if (dev)
+		ksz_switch_remove(dev);
+
+	return 0;
+}
+
+static const struct of_device_id ksz_dt_ids[] = {
+	{ .compatible = "microchip,ksz9477" },
+	{},
+};
+MODULE_DEVICE_TABLE(of, ksz_dt_ids);
+
+static struct spi_driver ksz_spi_driver = {
+	.driver = {
+		.name	= "ksz9477-switch",
+		.owner	= THIS_MODULE,
+		.of_match_table = of_match_ptr(ksz_dt_ids),
+	},
+	.probe	= ksz_spi_probe,
+	.remove	= ksz_spi_remove,
+};
+
+module_spi_driver(ksz_spi_driver);
+
+MODULE_AUTHOR("Woojung Huh <Woojung.Huh@microchip.com>");
+MODULE_DESCRIPTION("Microchip KSZ Series Switch SPI access Driver");
+MODULE_LICENSE("GPL");

drivers/net/phy/micrel.c

@@ -20,6 +20,7 @@
  *			   ksz8081, ksz8091,
  *			   ksz8061,
  *		Switch : ksz8873, ksz886x
+ *			 ksz9477
  */
 
 #include <linux/kernel.h>
@@ -996,6 +997,16 @@ static struct phy_driver ksphy_driver[] = {
 	.read_status	= ksz8873mll_read_status,
 	.suspend	= genphy_suspend,
 	.resume		= genphy_resume,
+}, {
+	.phy_id		= PHY_ID_KSZ9477,
+	.phy_id_mask	= MICREL_PHY_ID_MASK,
+	.name		= "Microchip KSZ9477",
+	.features	= PHY_GBIT_FEATURES,
+	.config_init	= kszphy_config_init,
+	.config_aneg	= genphy_config_aneg,
+	.read_status	= genphy_read_status,
+	.suspend	= genphy_suspend,
+	.resume		= genphy_resume,
 } };
 
 module_phy_driver(ksphy_driver);

include/linux/micrel_phy.h

@@ -37,6 +37,8 @@
 
 #define PHY_ID_KSZ8795		0x00221550
 
+#define	PHY_ID_KSZ9477		0x00221631
+
 /* struct phy_device dev_flags definitions */
 #define MICREL_PHY_50MHZ_CLK	0x00000001
 #define MICREL_PHY_FXEN		0x00000002

include/linux/platform_data/microchip-ksz.h

+/*
+ * Microchip KSZ series switch platform data
+ *
+ * Copyright (C) 2017
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#ifndef __MICROCHIP_KSZ_H
+#define __MICROCHIP_KSZ_H
+
+#include <linux/kernel.h>
+
+struct ksz_platform_data {
+	u32 chip_id;
+	u16 enabled_ports;
+};
+
+#endif

include/net/dsa.h

@@ -31,6 +31,7 @@ enum dsa_tag_protocol {
 	DSA_TAG_PROTO_BRCM,
 	DSA_TAG_PROTO_DSA,
 	DSA_TAG_PROTO_EDSA,
+	DSA_TAG_PROTO_KSZ,
 	DSA_TAG_PROTO_LAN9303,
 	DSA_TAG_PROTO_MTK,
 	DSA_TAG_PROTO_QCA,

net/dsa/Kconfig

@@ -25,6 +25,9 @@ config NET_DSA_TAG_DSA
 config NET_DSA_TAG_EDSA
 	bool
 
+config NET_DSA_TAG_KSZ
+	bool
+
 config NET_DSA_TAG_LAN9303
 	bool
 

net/dsa/Makefile

@@ -6,6 +6,7 @@ dsa_core-y += dsa.o dsa2.o legacy.o port.o slave.o switch.o
 dsa_core-$(CONFIG_NET_DSA_TAG_BRCM) += tag_brcm.o
 dsa_core-$(CONFIG_NET_DSA_TAG_DSA) += tag_dsa.o
 dsa_core-$(CONFIG_NET_DSA_TAG_EDSA) += tag_edsa.o
+dsa_core-$(CONFIG_NET_DSA_TAG_KSZ) += tag_ksz.o
 dsa_core-$(CONFIG_NET_DSA_TAG_LAN9303) += tag_lan9303.o
 dsa_core-$(CONFIG_NET_DSA_TAG_MTK) += tag_mtk.o
 dsa_core-$(CONFIG_NET_DSA_TAG_QCA) += tag_qca.o

net/dsa/dsa.c

@@ -49,6 +49,9 @@ const struct dsa_device_ops *dsa_device_ops[DSA_TAG_LAST] = {
 #ifdef CONFIG_NET_DSA_TAG_EDSA
 	[DSA_TAG_PROTO_EDSA] = &edsa_netdev_ops,
 #endif
+#ifdef CONFIG_NET_DSA_TAG_KSZ
+	[DSA_TAG_PROTO_KSZ] = &ksz_netdev_ops,
+#endif
 #ifdef CONFIG_NET_DSA_TAG_LAN9303
 	[DSA_TAG_PROTO_LAN9303] = &lan9303_netdev_ops,
 #endif

net/dsa/dsa_priv.h

@@ -167,6 +167,9 @@ extern const struct dsa_device_ops dsa_netdev_ops;
 /* tag_edsa.c */
 extern const struct dsa_device_ops edsa_netdev_ops;
 
+/* tag_ksz.c */
+extern const struct dsa_device_ops ksz_netdev_ops;
+
 /* tag_lan9303.c */
 extern const struct dsa_device_ops lan9303_netdev_ops;
 

net/dsa/tag_ksz.c

+/*
+ * net/dsa/tag_ksz.c - Microchip KSZ Switch tag format handling
+ * Copyright (c) 2017 Microchip Technology
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/etherdevice.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <net/dsa.h>
+#include "dsa_priv.h"
+
+/* For Ingress (Host -> KSZ), 2 bytes are added before FCS.
+ * ---------------------------------------------------------------------------
+ * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|tag1(1byte)|FCS(4bytes)
+ * ---------------------------------------------------------------------------
+ * tag0 : Prioritization (not used now)
+ * tag1 : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x10=port5)
+ *
+ * For Egress (KSZ -> Host), 1 byte is added before FCS.
+ * ---------------------------------------------------------------------------
+ * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|FCS(4bytes)
+ * ---------------------------------------------------------------------------
+ * tag0 : zero-based value represents port
+ *	  (eg, 0x00=port1, 0x02=port3, 0x06=port7)
+ */
+
+#define	KSZ_INGRESS_TAG_LEN	2
+#define	KSZ_EGRESS_TAG_LEN	1
+
+static struct sk_buff *ksz_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct dsa_slave_priv *p = netdev_priv(dev);
+	struct sk_buff *nskb;
+	int padlen;
+	u8 *tag;
+
+	padlen = (skb->len >= ETH_ZLEN) ? 0 : ETH_ZLEN - skb->len;
+
+	if (skb_tailroom(skb) >= padlen + KSZ_INGRESS_TAG_LEN) {
+		nskb = skb;
+	} else {
+		nskb = alloc_skb(NET_IP_ALIGN + skb->len +
+				 padlen + KSZ_INGRESS_TAG_LEN, GFP_ATOMIC);
+		if (!nskb) {
+			kfree_skb(skb);
+			return NULL;
+		}
+		skb_reserve(nskb, NET_IP_ALIGN);
+
+		skb_reset_mac_header(nskb);
+		skb_set_network_header(nskb,
+				       skb_network_header(skb) - skb->head);
+		skb_set_transport_header(nskb,
+					 skb_transport_header(skb) - skb->head);
+		skb_copy_and_csum_dev(skb, skb_put(nskb, skb->len));
+		kfree_skb(skb);
+	}
+
+	/* skb is freed when it fails */
+	if (skb_put_padto(nskb, nskb->len + padlen))
+		return NULL;
+
+	tag = skb_put(nskb, KSZ_INGRESS_TAG_LEN);
+	tag[0] = 0;
+	tag[1] = 1 << p->dp->index; /* destination port */
+
+	return nskb;
+}
+
+struct sk_buff *ksz_rcv(struct sk_buff *skb, struct net_device *dev,
+			struct packet_type *pt, struct net_device *orig_dev)
+{
+	struct dsa_switch_tree *dst = dev->dsa_ptr;
+	struct dsa_switch *ds;
+	u8 *tag;
+	int source_port;
+
+	ds = dst->cpu_dp->ds;
+
+	tag = skb_tail_pointer(skb) - KSZ_EGRESS_TAG_LEN;
+
+	source_port = tag[0] & 7;
+	if (source_port >= ds->num_ports || !ds->ports[source_port].netdev)
+		return NULL;
+
+	pskb_trim_rcsum(skb, skb->len - KSZ_EGRESS_TAG_LEN);
+
+	skb->dev = ds->ports[source_port].netdev;
+
+	return skb;
+}
+
+const struct dsa_device_ops ksz_netdev_ops = {
+	.xmit	= ksz_xmit,
+	.rcv	= ksz_rcv,
+};