linux/drivers/net/gianfar_mii.c

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/*
* drivers/net/gianfar_mii.c
*
* Gianfar Ethernet Driver -- MIIM bus implementation
* Provides Bus interface for MIIM regs
*
* Author: Andy Fleming
* Maintainer: Kumar Gala
*
* Copyright (c) 2002-2004 Freescale Semiconductor, Inc.
*
* 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/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/unistd.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
#include <linux/spinlock.h>
#include <linux/mm.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/crc32.h>
#include <linux/mii.h>
#include <linux/phy.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/uaccess.h>
#include "gianfar.h"
#include "gianfar_mii.h"
/*
* Write value to the PHY at mii_id at register regnum,
* on the bus attached to the local interface, which may be different from the
* generic mdio bus (tied to a single interface), waiting until the write is
* done before returning. This is helpful in programming interfaces like
* the TBI which control interfaces like onchip SERDES and are always tied to
* the local mdio pins, which may not be the same as system mdio bus, used for
* controlling the external PHYs, for example.
*/
int gfar_local_mdio_write(struct gfar_mii __iomem *regs, int mii_id,
int regnum, u16 value)
{
/* Set the PHY address and the register address we want to write */
gfar_write(&regs->miimadd, (mii_id << 8) | regnum);
/* Write out the value we want */
gfar_write(&regs->miimcon, value);
/* Wait for the transaction to finish */
while (gfar_read(&regs->miimind) & MIIMIND_BUSY)
cpu_relax();
return 0;
}
/*
* Read the bus for PHY at addr mii_id, register regnum, and
* return the value. Clears miimcom first. All PHY operation
* done on the bus attached to the local interface,
* which may be different from the generic mdio bus
* This is helpful in programming interfaces like
* the TBI which, inturn, control interfaces like onchip SERDES
* and are always tied to the local mdio pins, which may not be the
* same as system mdio bus, used for controlling the external PHYs, for eg.
*/
int gfar_local_mdio_read(struct gfar_mii __iomem *regs, int mii_id, int regnum)
{
u16 value;
/* Set the PHY address and the register address we want to read */
gfar_write(&regs->miimadd, (mii_id << 8) | regnum);
/* Clear miimcom, and then initiate a read */
gfar_write(&regs->miimcom, 0);
gfar_write(&regs->miimcom, MII_READ_COMMAND);
/* Wait for the transaction to finish */
while (gfar_read(&regs->miimind) & (MIIMIND_NOTVALID | MIIMIND_BUSY))
cpu_relax();
/* Grab the value of the register from miimstat */
value = gfar_read(&regs->miimstat);
return value;
}
/* Write value to the PHY at mii_id at register regnum,
* on the bus, waiting until the write is done before returning.
* All PHY configuration is done through the TSEC1 MIIM regs */
int gfar_mdio_write(struct mii_bus *bus, int mii_id, int regnum, u16 value)
{
struct gfar_mii __iomem *regs = (void __iomem *)bus->priv;
/* Write to the local MII regs */
return(gfar_local_mdio_write(regs, mii_id, regnum, value));
}
/* Read the bus for PHY at addr mii_id, register regnum, and
* return the value. Clears miimcom first. All PHY
* configuration has to be done through the TSEC1 MIIM regs */
int gfar_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
{
struct gfar_mii __iomem *regs = (void __iomem *)bus->priv;
/* Read the local MII regs */
return(gfar_local_mdio_read(regs, mii_id, regnum));
}
/* Reset the MIIM registers, and wait for the bus to free */
int gfar_mdio_reset(struct mii_bus *bus)
{
struct gfar_mii __iomem *regs = (void __iomem *)bus->priv;
unsigned int timeout = PHY_INIT_TIMEOUT;
mutex_lock(&bus->mdio_lock);
/* Reset the management interface */
gfar_write(&regs->miimcfg, MIIMCFG_RESET);
/* Setup the MII Mgmt clock speed */
gfar_write(&regs->miimcfg, MIIMCFG_INIT_VALUE);
/* Wait until the bus is free */
while ((gfar_read(&regs->miimind) & MIIMIND_BUSY) &&
timeout--)
cpu_relax();
mutex_unlock(&bus->mdio_lock);
if(timeout <= 0) {
printk(KERN_ERR "%s: The MII Bus is stuck!\n",
bus->name);
return -EBUSY;
}
return 0;
}
int gfar_mdio_probe(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct gianfar_mdio_data *pdata;
struct gfar_mii __iomem *regs;
struct mii_bus *new_bus;
struct resource *r;
int err = 0;
if (NULL == dev)
return -EINVAL;
new_bus = kzalloc(sizeof(struct mii_bus), GFP_KERNEL);
if (NULL == new_bus)
return -ENOMEM;
new_bus->name = "Gianfar MII Bus",
new_bus->read = &gfar_mdio_read,
new_bus->write = &gfar_mdio_write,
new_bus->reset = &gfar_mdio_reset,
new_bus->id = pdev->id;
pdata = (struct gianfar_mdio_data *)pdev->dev.platform_data;
if (NULL == pdata) {
printk(KERN_ERR "gfar mdio %d: Missing platform data!\n", pdev->id);
return -ENODEV;
}
r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
/* Set the PHY base address */
regs = ioremap(r->start, sizeof (struct gfar_mii));
if (NULL == regs) {
err = -ENOMEM;
goto reg_map_fail;
}
new_bus->priv = (void __force *)regs;
new_bus->irq = pdata->irq;
new_bus->dev = dev;
dev_set_drvdata(dev, new_bus);
err = mdiobus_register(new_bus);
if (0 != err) {
printk (KERN_ERR "%s: Cannot register as MDIO bus\n",
new_bus->name);
goto bus_register_fail;
}
return 0;
bus_register_fail:
iounmap(regs);
reg_map_fail:
kfree(new_bus);
return err;
}
int gfar_mdio_remove(struct device *dev)
{
struct mii_bus *bus = dev_get_drvdata(dev);
mdiobus_unregister(bus);
dev_set_drvdata(dev, NULL);
iounmap((void __iomem *)bus->priv);
bus->priv = NULL;
kfree(bus);
return 0;
}
static struct device_driver gianfar_mdio_driver = {
.name = "fsl-gianfar_mdio",
.bus = &platform_bus_type,
.probe = gfar_mdio_probe,
.remove = gfar_mdio_remove,
};
int __init gfar_mdio_init(void)
{
return driver_register(&gianfar_mdio_driver);
}
void gfar_mdio_exit(void)
{
driver_unregister(&gianfar_mdio_driver);
}