2 * drivers/net/gianfar_mii.c
4 * Gianfar Ethernet Driver -- MIIM bus implementation
5 * Provides Bus interface for MIIM regs
8 * Maintainer: Kumar Gala
10 * Copyright (c) 2002-2004 Freescale Semiconductor, Inc.
12 * This program is free software; you can redistribute it and/or modify it
13 * under the terms of the GNU General Public License as published by the
14 * Free Software Foundation; either version 2 of the License, or (at your
15 * option) any later version.
19 #include <linux/kernel.h>
20 #include <linux/string.h>
21 #include <linux/errno.h>
22 #include <linux/unistd.h>
23 #include <linux/slab.h>
24 #include <linux/interrupt.h>
25 #include <linux/init.h>
26 #include <linux/delay.h>
27 #include <linux/netdevice.h>
28 #include <linux/etherdevice.h>
29 #include <linux/skbuff.h>
30 #include <linux/spinlock.h>
32 #include <linux/module.h>
33 #include <linux/platform_device.h>
35 #include <linux/crc32.h>
36 #include <linux/mii.h>
37 #include <linux/phy.h>
41 #include <asm/uaccess.h>
44 #include "gianfar_mii.h"
47 * Write value to the PHY at mii_id at register regnum,
48 * on the bus attached to the local interface, which may be different from the
49 * generic mdio bus (tied to a single interface), waiting until the write is
50 * done before returning. This is helpful in programming interfaces like
51 * the TBI which control interfaces like onchip SERDES and are always tied to
52 * the local mdio pins, which may not be the same as system mdio bus, used for
53 * controlling the external PHYs, for example.
55 int gfar_local_mdio_write(struct gfar_mii *regs, int mii_id,
56 int regnum, u16 value)
58 /* Set the PHY address and the register address we want to write */
59 gfar_write(®s->miimadd, (mii_id << 8) | regnum);
61 /* Write out the value we want */
62 gfar_write(®s->miimcon, value);
64 /* Wait for the transaction to finish */
65 while (gfar_read(®s->miimind) & MIIMIND_BUSY)
72 * Read the bus for PHY at addr mii_id, register regnum, and
73 * return the value. Clears miimcom first. All PHY operation
74 * done on the bus attached to the local interface,
75 * which may be different from the generic mdio bus
76 * This is helpful in programming interfaces like
77 * the TBI which, inturn, control interfaces like onchip SERDES
78 * and are always tied to the local mdio pins, which may not be the
79 * same as system mdio bus, used for controlling the external PHYs, for eg.
81 int gfar_local_mdio_read(struct gfar_mii *regs, int mii_id, int regnum)
86 /* Set the PHY address and the register address we want to read */
87 gfar_write(®s->miimadd, (mii_id << 8) | regnum);
89 /* Clear miimcom, and then initiate a read */
90 gfar_write(®s->miimcom, 0);
91 gfar_write(®s->miimcom, MII_READ_COMMAND);
93 /* Wait for the transaction to finish */
94 while (gfar_read(®s->miimind) & (MIIMIND_NOTVALID | MIIMIND_BUSY))
97 /* Grab the value of the register from miimstat */
98 value = gfar_read(®s->miimstat);
103 /* Write value to the PHY at mii_id at register regnum,
104 * on the bus, waiting until the write is done before returning.
105 * All PHY configuration is done through the TSEC1 MIIM regs */
106 int gfar_mdio_write(struct mii_bus *bus, int mii_id, int regnum, u16 value)
108 struct gfar_mii __iomem *regs = (void __iomem *)bus->priv;
110 /* Write to the local MII regs */
111 return(gfar_local_mdio_write(regs, mii_id, regnum, value));
114 /* Read the bus for PHY at addr mii_id, register regnum, and
115 * return the value. Clears miimcom first. All PHY
116 * configuration has to be done through the TSEC1 MIIM regs */
117 int gfar_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
119 struct gfar_mii __iomem *regs = (void __iomem *)bus->priv;
121 /* Read the local MII regs */
122 return(gfar_local_mdio_read(regs, mii_id, regnum));
125 /* Reset the MIIM registers, and wait for the bus to free */
126 int gfar_mdio_reset(struct mii_bus *bus)
128 struct gfar_mii __iomem *regs = (void __iomem *)bus->priv;
129 unsigned int timeout = PHY_INIT_TIMEOUT;
131 spin_lock_bh(&bus->mdio_lock);
133 /* Reset the management interface */
134 gfar_write(®s->miimcfg, MIIMCFG_RESET);
136 /* Setup the MII Mgmt clock speed */
137 gfar_write(®s->miimcfg, MIIMCFG_INIT_VALUE);
139 /* Wait until the bus is free */
140 while ((gfar_read(®s->miimind) & MIIMIND_BUSY) &&
144 spin_unlock_bh(&bus->mdio_lock);
147 printk(KERN_ERR "%s: The MII Bus is stuck!\n",
156 int gfar_mdio_probe(struct device *dev)
158 struct platform_device *pdev = to_platform_device(dev);
159 struct gianfar_mdio_data *pdata;
160 struct gfar_mii __iomem *regs;
161 struct mii_bus *new_bus;
168 new_bus = kzalloc(sizeof(struct mii_bus), GFP_KERNEL);
173 new_bus->name = "Gianfar MII Bus",
174 new_bus->read = &gfar_mdio_read,
175 new_bus->write = &gfar_mdio_write,
176 new_bus->reset = &gfar_mdio_reset,
177 new_bus->id = pdev->id;
179 pdata = (struct gianfar_mdio_data *)pdev->dev.platform_data;
182 printk(KERN_ERR "gfar mdio %d: Missing platform data!\n", pdev->id);
186 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
188 /* Set the PHY base address */
189 regs = ioremap(r->start, sizeof (struct gfar_mii));
196 new_bus->priv = (void __force *)regs;
198 new_bus->irq = pdata->irq;
201 dev_set_drvdata(dev, new_bus);
203 err = mdiobus_register(new_bus);
206 printk (KERN_ERR "%s: Cannot register as MDIO bus\n",
208 goto bus_register_fail;
222 int gfar_mdio_remove(struct device *dev)
224 struct mii_bus *bus = dev_get_drvdata(dev);
226 mdiobus_unregister(bus);
228 dev_set_drvdata(dev, NULL);
230 iounmap((void __iomem *)bus->priv);
237 static struct device_driver gianfar_mdio_driver = {
238 .name = "fsl-gianfar_mdio",
239 .bus = &platform_bus_type,
240 .probe = gfar_mdio_probe,
241 .remove = gfar_mdio_remove,
244 int __init gfar_mdio_init(void)
246 return driver_register(&gianfar_mdio_driver);
249 void __exit gfar_mdio_exit(void)
251 driver_unregister(&gianfar_mdio_driver);