aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/net/gianfar_mii.c
blob: 0e2595d24933cd8f6549153782d87010672ee2d7 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
/*
 * 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 */
static 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;
}


static 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 gfar __iomem *enet_regs;
	struct mii_bus *new_bus;
	struct resource *r;
	int i, err = 0;

	if (NULL == dev)
		return -EINVAL;

	new_bus = mdiobus_alloc();
	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,
	snprintf(new_bus->id, MII_BUS_ID_SIZE, "%x", 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->parent = dev;
	dev_set_drvdata(dev, new_bus);

	/*
	 * This is mildly evil, but so is our hardware for doing this.
	 * Also, we have to cast back to struct gfar_mii because of
	 * definition weirdness done in gianfar.h.
	 */
	enet_regs = (struct gfar __iomem *)
		((char *)regs - offsetof(struct gfar, gfar_mii_regs));

	/* Scan the bus, looking for an empty spot for TBIPA */
	gfar_write(&enet_regs->tbipa, 0);
	for (i = PHY_MAX_ADDR; i > 0; i--) {
		u32 phy_id;

		err = get_phy_id(new_bus, i, &phy_id);
		if (err)
			goto bus_register_fail;

		if (phy_id == 0xffffffff)
			break;
	}

	/* The bus is full.  We don't support using 31 PHYs, sorry */
	if (i == 0) {
		err = -EBUSY;

		goto bus_register_fail;
	}

	gfar_write(&enet_regs->tbipa, i);

	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:
	mdiobus_free(new_bus);

	return err;
}


static 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;
	mdiobus_free(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,
};

static int match_mdio_bus(struct device *dev, void *data)
{
	const struct gfar_private *priv = data;
	const struct platform_device *pdev = to_platform_device(dev);

	return !strcmp(pdev->name, gianfar_mdio_driver.name) &&
		pdev->id == priv->einfo->mdio_bus;
}

/* Given a gfar_priv structure, find the mii_bus controlled by this device (not
 * necessarily the same as the bus the gfar's PHY is on), if one exists.
 * Normally only the first gianfar controls a mii_bus.  */
struct mii_bus *gfar_get_miibus(const struct gfar_private *priv)
{
	/*const*/ struct device *d;

	d = bus_find_device(gianfar_mdio_driver.bus, NULL, (void *)priv,
			    match_mdio_bus);
	return d ? dev_get_drvdata(d) : NULL;
}

int __init gfar_mdio_init(void)
{
	return driver_register(&gianfar_mdio_driver);
}

void gfar_mdio_exit(void)
{
	driver_unregister(&gianfar_mdio_driver);
}