summaryrefslogtreecommitdiff
path: root/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c
blob: cc15039eaa4739a33e916b5f9506ce0b1c0f4ccc (plain)
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
/*******************************************************************************
  STMMAC Ethernet Driver -- MDIO bus implementation
  Provides Bus interface for MII registers

  Copyright (C) 2007-2009  STMicroelectronics Ltd

  This program is free software; you can redistribute it and/or modify it
  under the terms and conditions of the GNU General Public License,
  version 2, as published by the Free Software Foundation.

  This program is distributed in the hope 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.,
  51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.

  The full GNU General Public License is included in this distribution in
  the file called "COPYING".

  Author: Carl Shaw <carl.shaw@st.com>
  Maintainer: Giuseppe Cavallaro <peppe.cavallaro@st.com>
*******************************************************************************/

#include <linux/mii.h>
#include <linux/phy.h>
#include <linux/slab.h>
#include <asm/io.h>

#include "stmmac.h"

#define MII_BUSY 0x00000001
#define MII_WRITE 0x00000002

static int stmmac_mdio_busy_wait(void __iomem *ioaddr, unsigned int mii_addr)
{
	unsigned long curr;
	unsigned long finish = jiffies + 3 * HZ;

	do {
		curr = jiffies;
		if (readl(ioaddr + mii_addr) & MII_BUSY)
			cpu_relax();
		else
			return 0;
	} while (!time_after_eq(curr, finish));

	return -EBUSY;
}

/**
 * stmmac_mdio_read
 * @bus: points to the mii_bus structure
 * @phyaddr: MII addr reg bits 15-11
 * @phyreg: MII addr reg bits 10-6
 * Description: it reads data from the MII register from within the phy device.
 * For the 7111 GMAC, we must set the bit 0 in the MII address register while
 * accessing the PHY registers.
 * Fortunately, it seems this has no drawback for the 7109 MAC.
 */
static int stmmac_mdio_read(struct mii_bus *bus, int phyaddr, int phyreg)
{
	struct net_device *ndev = bus->priv;
	struct stmmac_priv *priv = netdev_priv(ndev);
	unsigned int mii_address = priv->hw->mii.addr;
	unsigned int mii_data = priv->hw->mii.data;

	int data;
	u16 regValue = (((phyaddr << 11) & (0x0000F800)) |
			((phyreg << 6) & (0x000007C0)));
	regValue |= MII_BUSY | ((priv->clk_csr & 0xF) << 2);

	if (stmmac_mdio_busy_wait(priv->ioaddr, mii_address))
		return -EBUSY;

	writel(regValue, priv->ioaddr + mii_address);

	if (stmmac_mdio_busy_wait(priv->ioaddr, mii_address))
		return -EBUSY;

	/* Read the data from the MII data register */
	data = (int)readl(priv->ioaddr + mii_data);

	return data;
}

/**
 * stmmac_mdio_write
 * @bus: points to the mii_bus structure
 * @phyaddr: MII addr reg bits 15-11
 * @phyreg: MII addr reg bits 10-6
 * @phydata: phy data
 * Description: it writes the data into the MII register from within the device.
 */
static int stmmac_mdio_write(struct mii_bus *bus, int phyaddr, int phyreg,
			     u16 phydata)
{
	struct net_device *ndev = bus->priv;
	struct stmmac_priv *priv = netdev_priv(ndev);
	unsigned int mii_address = priv->hw->mii.addr;
	unsigned int mii_data = priv->hw->mii.data;

	u16 value =
	    (((phyaddr << 11) & (0x0000F800)) | ((phyreg << 6) & (0x000007C0)))
	    | MII_WRITE;

	value |= MII_BUSY | ((priv->clk_csr & 0xF) << 2);

	/* Wait until any existing MII operation is complete */
	if (stmmac_mdio_busy_wait(priv->ioaddr, mii_address))
		return -EBUSY;

	/* Set the MII address register to write */
	writel(phydata, priv->ioaddr + mii_data);
	writel(value, priv->ioaddr + mii_address);

	/* Wait until any existing MII operation is complete */
	return stmmac_mdio_busy_wait(priv->ioaddr, mii_address);
}

/**
 * stmmac_mdio_reset
 * @bus: points to the mii_bus structure
 * Description: reset the MII bus
 */
static int stmmac_mdio_reset(struct mii_bus *bus)
{
#if defined(CONFIG_STMMAC_PLATFORM)
	struct net_device *ndev = bus->priv;
	struct stmmac_priv *priv = netdev_priv(ndev);
	unsigned int mii_address = priv->hw->mii.addr;

	if (priv->plat->mdio_bus_data->phy_reset) {
		pr_debug("stmmac_mdio_reset: calling phy_reset\n");
		priv->plat->mdio_bus_data->phy_reset(priv->plat->bsp_priv);
	}

	/* This is a workaround for problems with the STE101P PHY.
	 * It doesn't complete its reset until at least one clock cycle
	 * on MDC, so perform a dummy mdio read.
	 */
	writel(0, priv->ioaddr + mii_address);
#endif
	return 0;
}

/**
 * stmmac_mdio_register
 * @ndev: net device structure
 * Description: it registers the MII bus
 */
int stmmac_mdio_register(struct net_device *ndev)
{
	int err = 0;
	struct mii_bus *new_bus;
	int *irqlist;
	struct stmmac_priv *priv = netdev_priv(ndev);
	struct stmmac_mdio_bus_data *mdio_bus_data = priv->plat->mdio_bus_data;
	int addr, found;

	if (!mdio_bus_data)
		return 0;

	new_bus = mdiobus_alloc();
	if (new_bus == NULL)
		return -ENOMEM;

	if (mdio_bus_data->irqs)
		irqlist = mdio_bus_data->irqs;
	else
		irqlist = priv->mii_irq;

	new_bus->name = "stmmac";
	new_bus->read = &stmmac_mdio_read;
	new_bus->write = &stmmac_mdio_write;
	new_bus->reset = &stmmac_mdio_reset;
	snprintf(new_bus->id, MII_BUS_ID_SIZE, "%s-%x",
		 new_bus->name, priv->plat->bus_id);
	new_bus->priv = ndev;
	new_bus->irq = irqlist;
	new_bus->phy_mask = mdio_bus_data->phy_mask;
	new_bus->parent = priv->device;
	err = mdiobus_register(new_bus);
	if (err != 0) {
		pr_err("%s: Cannot register as MDIO bus\n", new_bus->name);
		goto bus_register_fail;
	}

	found = 0;
	for (addr = 0; addr < PHY_MAX_ADDR; addr++) {
		struct phy_device *phydev = new_bus->phy_map[addr];
		if (phydev) {
			int act = 0;
			char irq_num[4];
			char *irq_str;

			/*
			 * If an IRQ was provided to be assigned after
			 * the bus probe, do it here.
			 */
			if ((mdio_bus_data->irqs == NULL) &&
			    (mdio_bus_data->probed_phy_irq > 0)) {
				irqlist[addr] = mdio_bus_data->probed_phy_irq;
				phydev->irq = mdio_bus_data->probed_phy_irq;
			}

			/*
			 * If we're  going to bind the MAC to this PHY bus,
			 * and no PHY number was provided to the MAC,
			 * use the one probed here.
			 */
			if (priv->plat->phy_addr == -1)
				priv->plat->phy_addr = addr;

			act = (priv->plat->phy_addr == addr);
			switch (phydev->irq) {
			case PHY_POLL:
				irq_str = "POLL";
				break;
			case PHY_IGNORE_INTERRUPT:
				irq_str = "IGNORE";
				break;
			default:
				sprintf(irq_num, "%d", phydev->irq);
				irq_str = irq_num;
				break;
			}
			pr_info("%s: PHY ID %08x at %d IRQ %s (%s)%s\n",
				ndev->name, phydev->phy_id, addr,
				irq_str, dev_name(&phydev->dev),
				act ? " active" : "");
			found = 1;
		}
	}

	if (!found) {
		pr_warning("%s: No PHY found\n", ndev->name);
		mdiobus_unregister(new_bus);
		mdiobus_free(new_bus);
		return -ENODEV;
	}

	priv->mii = new_bus;

	return 0;

bus_register_fail:
	mdiobus_free(new_bus);
	return err;
}

/**
 * stmmac_mdio_unregister
 * @ndev: net device structure
 * Description: it unregisters the MII bus
 */
int stmmac_mdio_unregister(struct net_device *ndev)
{
	struct stmmac_priv *priv = netdev_priv(ndev);

	if (!priv->mii)
		return 0;

	mdiobus_unregister(priv->mii);
	priv->mii->priv = NULL;
	mdiobus_free(priv->mii);
	priv->mii = NULL;

	return 0;
}