Commit f20136eb authored by Cyril Chemparathy's avatar Cyril Chemparathy Committed by Kevin Hilman
Browse files

net: davinci_emac: separate out davinci mdio 



Davinci's MDIO controller is present on other TI devices, without an
accompanying EMAC.  For example, on tnetv107x, the same MDIO module is used in
conjunction with a 3-port switch hardware.

By separating the MDIO controller code into its own platform driver, this
patch allows common logic to be reused on such platforms.

Signed-off-by: default avatarCyril Chemparathy <cyril@ti.com>
Tested-by: default avatarMichael Williamson <michael.williamson@criticallink.com>
Tested-by: default avatarCaglar Akyuz <caglarakyuz@gmail.com>
Signed-off-by: default avatarKevin Hilman <khilman@deeprootsystems.com>
parent 87748823

drivers/net/Kconfig

+10 −0
Original line number Diff line number Diff line
@@ -958,6 +958,16 @@ config TI_DAVINCI_EMAC 
	  To compile this driver as a module, choose M here: the module

	  will be called davinci_emac_driver.  This is recommended.



config TI_DAVINCI_MDIO

	tristate "TI DaVinci MDIO Support"

	depends on ARM && ( ARCH_DAVINCI || ARCH_OMAP3 )

	select PHYLIB

	help

	  This driver supports TI's DaVinci MDIO module.



	  To compile this driver as a module, choose M here: the module

	  will be called davinci_mdio.  This is recommended.



config DM9000

	tristate "DM9000 support"

	depends on ARM || BLACKFIN || MIPS

drivers/net/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -7,6 +7,7 @@ obj-$(CONFIG_MDIO) += mdio.o 
obj-$(CONFIG_PHYLIB) += phy/



obj-$(CONFIG_TI_DAVINCI_EMAC) += davinci_emac.o

obj-$(CONFIG_TI_DAVINCI_MDIO) += davinci_mdio.o



obj-$(CONFIG_E1000) += e1000/

obj-$(CONFIG_E1000E) += e1000e/

drivers/net/davinci_mdio.c

0 → 100644
+475 −0
Original line number Diff line number Diff line 
/*

 * DaVinci MDIO Module driver

 *

 * Copyright (C) 2010 Texas Instruments.

 *

 * Shamelessly ripped out of davinci_emac.c, original copyrights follow:

 *

 * Copyright (C) 2009 Texas Instruments.

 *

 * ---------------------------------------------------------------------------

 *

 * 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.

 *

 * 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 for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

 * ---------------------------------------------------------------------------

 */

#include <linux/module.h>

#include <linux/kernel.h>

#include <linux/platform_device.h>

#include <linux/delay.h>

#include <linux/sched.h>

#include <linux/slab.h>

#include <linux/phy.h>

#include <linux/clk.h>

#include <linux/err.h>

#include <linux/io.h>

#include <linux/davinci_emac.h>



/*

 * This timeout definition is a worst-case ultra defensive measure against

 * unexpected controller lock ups.  Ideally, we should never ever hit this

 * scenario in practice.

 */

#define MDIO_TIMEOUT		100 /* msecs */



#define PHY_REG_MASK		0x1f

#define PHY_ID_MASK		0x1f



#define DEF_OUT_FREQ		2200000		/* 2.2 MHz */



struct davinci_mdio_regs {

	u32	version;

	u32	control;

#define CONTROL_IDLE		BIT(31)

#define CONTROL_ENABLE		BIT(30)

#define CONTROL_MAX_DIV		(0xff)



	u32	alive;

	u32	link;

	u32	linkintraw;

	u32	linkintmasked;

	u32	__reserved_0[2];

	u32	userintraw;

	u32	userintmasked;

	u32	userintmaskset;

	u32	userintmaskclr;

	u32	__reserved_1[20];



	struct {

		u32	access;

#define USERACCESS_GO		BIT(31)

#define USERACCESS_WRITE	BIT(30)

#define USERACCESS_ACK		BIT(29)

#define USERACCESS_READ		(0)

#define USERACCESS_DATA		(0xffff)



		u32	physel;

	}	user[0];

};



struct mdio_platform_data default_pdata = {

	.bus_freq = DEF_OUT_FREQ,

};



struct davinci_mdio_data {

	struct mdio_platform_data pdata;

	struct davinci_mdio_regs __iomem *regs;

	spinlock_t	lock;

	struct clk	*clk;

	struct device	*dev;

	struct mii_bus	*bus;

	bool		suspended;

	unsigned long	access_time; /* jiffies */

};



static void __davinci_mdio_reset(struct davinci_mdio_data *data)

{

	u32 mdio_in, div, mdio_out_khz, access_time;



	mdio_in = clk_get_rate(data->clk);

	div = (mdio_in / data->pdata.bus_freq) - 1;

	if (div > CONTROL_MAX_DIV)

		div = CONTROL_MAX_DIV;



	/* set enable and clock divider */

	__raw_writel(div | CONTROL_ENABLE, &data->regs->control);



	/*

	 * One mdio transaction consists of:

	 *	32 bits of preamble

	 *	32 bits of transferred data

	 *	24 bits of bus yield (not needed unless shared?)

	 */

	mdio_out_khz = mdio_in / (1000 * (div + 1));

	access_time  = (88 * 1000) / mdio_out_khz;



	/*

	 * In the worst case, we could be kicking off a user-access immediately

	 * after the mdio bus scan state-machine triggered its own read.  If

	 * so, our request could get deferred by one access cycle.  We

	 * defensively allow for 4 access cycles.

	 */

	data->access_time = usecs_to_jiffies(access_time * 4);

	if (!data->access_time)

		data->access_time = 1;

}



static int davinci_mdio_reset(struct mii_bus *bus)

{

	struct davinci_mdio_data *data = bus->priv;

	u32 phy_mask, ver;



	__davinci_mdio_reset(data);



	/* wait for scan logic to settle */

	msleep(PHY_MAX_ADDR * data->access_time);



	/* dump hardware version info */

	ver = __raw_readl(&data->regs->version);

	dev_info(data->dev, "davinci mdio revision %d.%d\n",

		 (ver >> 8) & 0xff, ver & 0xff);



	/* get phy mask from the alive register */

	phy_mask = __raw_readl(&data->regs->alive);

	if (phy_mask) {

		/* restrict mdio bus to live phys only */

		dev_info(data->dev, "detected phy mask %x\n", ~phy_mask);

		phy_mask = ~phy_mask;

	} else {

		/* desperately scan all phys */

		dev_warn(data->dev, "no live phy, scanning all\n");

		phy_mask = 0;

	}

	data->bus->phy_mask = phy_mask;



	return 0;

}



/* wait until hardware is ready for another user access */

static inline int wait_for_user_access(struct davinci_mdio_data *data)

{

	struct davinci_mdio_regs __iomem *regs = data->regs;

	unsigned long timeout = jiffies + msecs_to_jiffies(MDIO_TIMEOUT);

	u32 reg;



	while (time_after(timeout, jiffies)) {

		reg = __raw_readl(&regs->user[0].access);

		if ((reg & USERACCESS_GO) == 0)

			return 0;



		reg = __raw_readl(&regs->control);

		if ((reg & CONTROL_IDLE) == 0)

			continue;



		/*

		 * An emac soft_reset may have clobbered the mdio controller's

		 * state machine.  We need to reset and retry the current

		 * operation

		 */

		dev_warn(data->dev, "resetting idled controller\n");

		__davinci_mdio_reset(data);

		return -EAGAIN;

	}

	dev_err(data->dev, "timed out waiting for user access\n");

	return -ETIMEDOUT;

}



/* wait until hardware state machine is idle */

static inline int wait_for_idle(struct davinci_mdio_data *data)

{

	struct davinci_mdio_regs __iomem *regs = data->regs;

	unsigned long timeout = jiffies + msecs_to_jiffies(MDIO_TIMEOUT);



	while (time_after(timeout, jiffies)) {

		if (__raw_readl(&regs->control) & CONTROL_IDLE)

			return 0;

	}

	dev_err(data->dev, "timed out waiting for idle\n");

	return -ETIMEDOUT;

}



static int davinci_mdio_read(struct mii_bus *bus, int phy_id, int phy_reg)

{

	struct davinci_mdio_data *data = bus->priv;

	u32 reg;

	int ret;



	if (phy_reg & ~PHY_REG_MASK || phy_id & ~PHY_ID_MASK)

		return -EINVAL;



	spin_lock(&data->lock);



	if (data->suspended) {

		spin_unlock(&data->lock);

		return -ENODEV;

	}



	reg = (USERACCESS_GO | USERACCESS_READ | (phy_reg << 21) |

	       (phy_id << 16));



	while (1) {

		ret = wait_for_user_access(data);

		if (ret == -EAGAIN)

			continue;

		if (ret < 0)

			break;



		__raw_writel(reg, &data->regs->user[0].access);



		ret = wait_for_user_access(data);

		if (ret == -EAGAIN)

			continue;

		if (ret < 0)

			break;



		reg = __raw_readl(&data->regs->user[0].access);

		ret = (reg & USERACCESS_ACK) ? (reg & USERACCESS_DATA) : -EIO;

		break;

	}



	spin_unlock(&data->lock);



	return ret;

}



static int davinci_mdio_write(struct mii_bus *bus, int phy_id,

			      int phy_reg, u16 phy_data)

{

	struct davinci_mdio_data *data = bus->priv;

	u32 reg;

	int ret;



	if (phy_reg & ~PHY_REG_MASK || phy_id & ~PHY_ID_MASK)

		return -EINVAL;



	spin_lock(&data->lock);



	if (data->suspended) {

		spin_unlock(&data->lock);

		return -ENODEV;

	}



	reg = (USERACCESS_GO | USERACCESS_WRITE | (phy_reg << 21) |

		   (phy_id << 16) | (phy_data & USERACCESS_DATA));



	while (1) {

		ret = wait_for_user_access(data);

		if (ret == -EAGAIN)

			continue;

		if (ret < 0)

			break;



		__raw_writel(reg, &data->regs->user[0].access);



		ret = wait_for_user_access(data);

		if (ret == -EAGAIN)

			continue;

		break;

	}



	spin_unlock(&data->lock);



	return 0;

}



static int __devinit davinci_mdio_probe(struct platform_device *pdev)

{

	struct mdio_platform_data *pdata = pdev->dev.platform_data;

	struct device *dev = &pdev->dev;

	struct davinci_mdio_data *data;

	struct resource *res;

	struct phy_device *phy;

	int ret, addr;



	data = kzalloc(sizeof(*data), GFP_KERNEL);

	if (!data) {

		dev_err(dev, "failed to alloc device data\n");

		return -ENOMEM;

	}



	data->pdata = pdata ? (*pdata) : default_pdata;



	data->bus = mdiobus_alloc();

	if (!data->bus) {

		dev_err(dev, "failed to alloc mii bus\n");

		ret = -ENOMEM;

		goto bail_out;

	}



	data->bus->name		= dev_name(dev);

	data->bus->read		= davinci_mdio_read,

	data->bus->write	= davinci_mdio_write,

	data->bus->reset	= davinci_mdio_reset,

	data->bus->parent	= dev;

	data->bus->priv		= data;

	snprintf(data->bus->id, MII_BUS_ID_SIZE, "%x", pdev->id);



	data->clk = clk_get(dev, NULL);

	if (IS_ERR(data->clk)) {

		data->clk = NULL;

		dev_err(dev, "failed to get device clock\n");

		ret = PTR_ERR(data->clk);

		goto bail_out;

	}



	clk_enable(data->clk);



	dev_set_drvdata(dev, data);

	data->dev = dev;

	spin_lock_init(&data->lock);



	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);

	if (!res) {

		dev_err(dev, "could not find register map resource\n");

		ret = -ENOENT;

		goto bail_out;

	}



	res = devm_request_mem_region(dev, res->start, resource_size(res),

					    dev_name(dev));

	if (!res) {

		dev_err(dev, "could not allocate register map resource\n");

		ret = -ENXIO;

		goto bail_out;

	}



	data->regs = devm_ioremap_nocache(dev, res->start, resource_size(res));

	if (!data->regs) {

		dev_err(dev, "could not map mdio registers\n");

		ret = -ENOMEM;

		goto bail_out;

	}



	/* register the mii bus */

	ret = mdiobus_register(data->bus);

	if (ret)

		goto bail_out;



	/* scan and dump the bus */

	for (addr = 0; addr < PHY_MAX_ADDR; addr++) {

		phy = data->bus->phy_map[addr];

		if (phy) {

			dev_info(dev, "phy[%d]: device %s, driver %s\n",

				 phy->addr, dev_name(&phy->dev),

				 phy->drv ? phy->drv->name : "unknown");

		}

	}



	return 0;



bail_out:

	if (data->bus)

		mdiobus_free(data->bus);



	if (data->clk) {

		clk_disable(data->clk);

		clk_put(data->clk);

	}



	kfree(data);



	return ret;

}



static int __devexit davinci_mdio_remove(struct platform_device *pdev)

{

	struct device *dev = &pdev->dev;

	struct davinci_mdio_data *data = dev_get_drvdata(dev);



	if (data->bus)

		mdiobus_free(data->bus);



	if (data->clk) {

		clk_disable(data->clk);

		clk_put(data->clk);

	}



	dev_set_drvdata(dev, NULL);



	kfree(data);



	return 0;

}



static int davinci_mdio_suspend(struct device *dev)

{

	struct davinci_mdio_data *data = dev_get_drvdata(dev);

	u32 ctrl;



	spin_lock(&data->lock);



	/* shutdown the scan state machine */

	ctrl = __raw_readl(&data->regs->control);

	ctrl &= ~CONTROL_ENABLE;

	__raw_writel(ctrl, &data->regs->control);

	wait_for_idle(data);



	if (data->clk)

		clk_disable(data->clk);



	data->suspended = true;

	spin_unlock(&data->lock);



	return 0;

}



static int davinci_mdio_resume(struct device *dev)

{

	struct davinci_mdio_data *data = dev_get_drvdata(dev);

	u32 ctrl;



	spin_lock(&data->lock);

	if (data->clk)

		clk_enable(data->clk);



	/* restart the scan state machine */

	ctrl = __raw_readl(&data->regs->control);

	ctrl |= CONTROL_ENABLE;

	__raw_writel(ctrl, &data->regs->control);



	data->suspended = false;

	spin_unlock(&data->lock);



	return 0;

}



static const struct dev_pm_ops davinci_mdio_pm_ops = {

	.suspend	= davinci_mdio_suspend,

	.resume		= davinci_mdio_resume,

};



static struct platform_driver davinci_mdio_driver = {

	.driver = {

		.name	 = "davinci_mdio",

		.owner	 = THIS_MODULE,

		.pm	 = &davinci_mdio_pm_ops,

	},

	.probe = davinci_mdio_probe,

	.remove = __devexit_p(davinci_mdio_remove),

};



static int __init davinci_mdio_init(void)

{

	return platform_driver_register(&davinci_mdio_driver);

}

device_initcall(davinci_mdio_init);



static void __exit davinci_mdio_exit(void)

{

	platform_driver_unregister(&davinci_mdio_driver);

}

module_exit(davinci_mdio_exit);



MODULE_LICENSE("GPL");

MODULE_DESCRIPTION("DaVinci MDIO driver");

include/linux/davinci_emac.h

+4 −0
Original line number Diff line number Diff line
@@ -14,6 +14,10 @@ 
#include <linux/if_ether.h>

#include <linux/memory.h>



struct mdio_platform_data {

	unsigned long		bus_freq;

};



struct emac_platform_data {

	char mac_addr[ETH_ALEN];

	u32 ctrl_reg_offset;

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