drivers/net/phy/mdio-mux-bcm-iproc.c - linux - Git at Google

 /*
  * Copyright 2016 Broadcom
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License, version 2, as
  * published by the Free Software Foundation (the "GPL").
  *
  * This program is distributed in the hope that it will be useful, but
  * WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  * General Public License version 2 (GPLv2) for more details.
  *
  * You should have received a copy of the GNU General Public License
  * version 2 (GPLv2) along with this source code.
  */
 #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>

 #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)
 {
 	unsigned int timeout = 1000; /* loop for 1s */
 	u32 val;

 	do {
 		val = readl(base + MDIO_STAT_OFFSET);
 		if ((val & MDIO_STAT_DONE) == result)
 			return 0;

 		usleep_range(1000, 2000);
 	} while (timeout--);

 	return -ETIMEDOUT;
 }

 /* 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 platform_device *pdev = to_platform_device(dev);
 	struct iproc_mdiomux_desc *md = platform_get_drvdata(pdev);

 	clk_disable_unprepare(md->core_clk);

 	return 0;
 }

 static int mdio_mux_iproc_resume(struct device *dev)
 {
 	struct platform_device *pdev = to_platform_device(dev);
 	struct iproc_mdiomux_desc *md = platform_get_drvdata(pdev);

 	clk_prepare_enable(md->core_clk);
 	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");
	/*
	* Copyright 2016 Broadcom
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License, version 2, as
	* published by the Free Software Foundation (the "GPL").
	*
	* This program is distributed in the hope that it will be useful, but
	* WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	* General Public License version 2 (GPLv2) for more details.
	*
	* You should have received a copy of the GNU General Public License
	* version 2 (GPLv2) along with this source code.
	*/
	#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>

	#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)
	{
	unsigned int timeout = 1000; /* loop for 1s */
	u32 val;

	do {
	val = readl(base + MDIO_STAT_OFFSET);
	if ((val & MDIO_STAT_DONE) == result)
	return 0;

	usleep_range(1000, 2000);
	} while (timeout--);

	return -ETIMEDOUT;
	}

	/* 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 platform_device *pdev = to_platform_device(dev);
	struct iproc_mdiomux_desc *md = platform_get_drvdata(pdev);

	clk_disable_unprepare(md->core_clk);

	return 0;
	}

	static int mdio_mux_iproc_resume(struct device *dev)
	{
	struct platform_device *pdev = to_platform_device(dev);
	struct iproc_mdiomux_desc *md = platform_get_drvdata(pdev);

	clk_prepare_enable(md->core_clk);
	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");