dsa: add DSA switch driver for Microchip KSZ9477

The KSZ9477 is a fully integrated layer 2, managed, 7 ports GigE switch
with numerous advanced features. 5 ports incorporate 10/100/1000 Mbps PHYs.
The other 2 ports have interfaces that can be configured as SGMII, RGMII, MII
or RMII. Either of these may connect directly to a host processor or
to an external PHY. The SGMII port may interface to a fiber optic transceiver.

This driver currently supports vlan, fdb, mdb & mirror dsa switch operations.

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

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

@@ -0,0 +1,12 @@
+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

@@ -0,0 +1,2 @@
+obj-$(CONFIG_MICROCHIP_KSZ)	        += ksz_common.o
+obj-$(CONFIG_MICROCHIP_KSZ_SPI_DRIVER)	+= ksz_spi.o

drivers/net/dsa/microchip/ksz_priv.h

@@ -0,0 +1,210 @@
+/*
+ * 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

@@ -0,0 +1,216 @@
+/*
+ * 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");

include/linux/platform_data/microchip-ksz.h

@@ -0,0 +1,29 @@
+/*
+ * 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