summaryrefslogtreecommitdiffstats
path: root/drivers/net/ethernet/stmicro/stmmac/stmmac_mdio.c
blob: 1341bb5f693c08b29c36e4bca387f529b415ae17 (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
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
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
// SPDX-License-Identifier: GPL-2.0-only
/*******************************************************************************
  STMMAC Ethernet Driver -- MDIO bus implementation
  Provides Bus interface for MII registers

  Copyright (C) 2007-2009  STMicroelectronics Ltd


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

#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/mii.h>
#include <linux/of.h>
#include <linux/of_gpio.h>
#include <linux/of_mdio.h>
#include <linux/phy.h>
#include <linux/slab.h>

#include "dwxgmac2.h"
#include "stmmac.h"

#define MII_BUSY 0x00000001
#define MII_WRITE 0x00000002

/* GMAC4 defines */
#define MII_GMAC4_GOC_SHIFT		2
#define MII_GMAC4_WRITE			(1 << MII_GMAC4_GOC_SHIFT)
#define MII_GMAC4_READ			(3 << MII_GMAC4_GOC_SHIFT)

/* XGMAC defines */
#define MII_XGMAC_SADDR			BIT(18)
#define MII_XGMAC_CMD_SHIFT		16
#define MII_XGMAC_WRITE			(1 << MII_XGMAC_CMD_SHIFT)
#define MII_XGMAC_READ			(3 << MII_XGMAC_CMD_SHIFT)
#define MII_XGMAC_BUSY			BIT(22)
#define MII_XGMAC_MAX_C22ADDR		3
#define MII_XGMAC_C22P_MASK		GENMASK(MII_XGMAC_MAX_C22ADDR, 0)

static int stmmac_xgmac2_c22_format(struct stmmac_priv *priv, int phyaddr,
				    int phyreg, u32 *hw_addr)
{
	unsigned int mii_data = priv->hw->mii.data;
	u32 tmp;

	/* HW does not support C22 addr >= 4 */
	if (phyaddr > MII_XGMAC_MAX_C22ADDR)
		return -ENODEV;
	/* Wait until any existing MII operation is complete */
	if (readl_poll_timeout(priv->ioaddr + mii_data, tmp,
			       !(tmp & MII_XGMAC_BUSY), 100, 10000))
		return -EBUSY;

	/* Set port as Clause 22 */
	tmp = readl(priv->ioaddr + XGMAC_MDIO_C22P);
	tmp &= ~MII_XGMAC_C22P_MASK;
	tmp |= BIT(phyaddr);
	writel(tmp, priv->ioaddr + XGMAC_MDIO_C22P);

	*hw_addr = (phyaddr << 16) | (phyreg & 0x1f);
	return 0;
}

static int stmmac_xgmac2_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;
	u32 tmp, addr, value = MII_XGMAC_BUSY;
	int ret;

	if (phyreg & MII_ADDR_C45) {
		return -EOPNOTSUPP;
	} else {
		ret = stmmac_xgmac2_c22_format(priv, phyaddr, phyreg, &addr);
		if (ret)
			return ret;
	}

	value |= (priv->clk_csr << priv->hw->mii.clk_csr_shift)
		& priv->hw->mii.clk_csr_mask;
	value |= MII_XGMAC_SADDR | MII_XGMAC_READ;

	/* Wait until any existing MII operation is complete */
	if (readl_poll_timeout(priv->ioaddr + mii_data, tmp,
			       !(tmp & MII_XGMAC_BUSY), 100, 10000))
		return -EBUSY;

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

	/* Wait until any existing MII operation is complete */
	if (readl_poll_timeout(priv->ioaddr + mii_data, tmp,
			       !(tmp & MII_XGMAC_BUSY), 100, 10000))
		return -EBUSY;

	/* Read the data from the MII data register */
	return readl(priv->ioaddr + mii_data) & GENMASK(15, 0);
}

static int stmmac_xgmac2_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;
	u32 addr, tmp, value = MII_XGMAC_BUSY;
	int ret;

	if (phyreg & MII_ADDR_C45) {
		return -EOPNOTSUPP;
	} else {
		ret = stmmac_xgmac2_c22_format(priv, phyaddr, phyreg, &addr);
		if (ret)
			return ret;
	}

	value |= (priv->clk_csr << priv->hw->mii.clk_csr_shift)
		& priv->hw->mii.clk_csr_mask;
	value |= phydata | MII_XGMAC_SADDR;
	value |= MII_XGMAC_WRITE;

	/* Wait until any existing MII operation is complete */
	if (readl_poll_timeout(priv->ioaddr + mii_data, tmp,
			       !(tmp & MII_XGMAC_BUSY), 100, 10000))
		return -EBUSY;

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

	/* Wait until any existing MII operation is complete */
	return readl_poll_timeout(priv->ioaddr + mii_data, tmp,
				  !(tmp & MII_XGMAC_BUSY), 100, 10000);
}

/**
 * stmmac_mdio_read
 * @bus: points to the mii_bus structure
 * @phyaddr: MII addr
 * @phyreg: MII reg
 * 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;
	u32 v;
	int data;
	u32 value = MII_BUSY;

	value |= (phyaddr << priv->hw->mii.addr_shift)
		& priv->hw->mii.addr_mask;
	value |= (phyreg << priv->hw->mii.reg_shift) & priv->hw->mii.reg_mask;
	value |= (priv->clk_csr << priv->hw->mii.clk_csr_shift)
		& priv->hw->mii.clk_csr_mask;
	if (priv->plat->has_gmac4)
		value |= MII_GMAC4_READ;

	if (readl_poll_timeout(priv->ioaddr + mii_address, v, !(v & MII_BUSY),
			       100, 10000))
		return -EBUSY;

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

	if (readl_poll_timeout(priv->ioaddr + mii_address, v, !(v & MII_BUSY),
			       100, 10000))
		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
 * @phyreg: MII reg
 * @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;
	u32 v;
	u32 value = MII_BUSY;

	value |= (phyaddr << priv->hw->mii.addr_shift)
		& priv->hw->mii.addr_mask;
	value |= (phyreg << priv->hw->mii.reg_shift) & priv->hw->mii.reg_mask;

	value |= (priv->clk_csr << priv->hw->mii.clk_csr_shift)
		& priv->hw->mii.clk_csr_mask;
	if (priv->plat->has_gmac4)
		value |= MII_GMAC4_WRITE;
	else
		value |= MII_WRITE;

	/* Wait until any existing MII operation is complete */
	if (readl_poll_timeout(priv->ioaddr + mii_address, v, !(v & MII_BUSY),
			       100, 10000))
		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 readl_poll_timeout(priv->ioaddr + mii_address, v, !(v & MII_BUSY),
				  100, 10000);
}

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

#ifdef CONFIG_OF
	if (priv->device->of_node) {
		if (data->reset_gpio < 0) {
			struct device_node *np = priv->device->of_node;

			if (!np)
				return 0;

			data->reset_gpio = of_get_named_gpio(np,
						"snps,reset-gpio", 0);
			if (data->reset_gpio < 0)
				return 0;

			data->active_low = of_property_read_bool(np,
						"snps,reset-active-low");
			of_property_read_u32_array(np,
				"snps,reset-delays-us", data->delays, 3);

			if (devm_gpio_request(priv->device, data->reset_gpio,
					      "mdio-reset"))
				return 0;
		}

		gpio_direction_output(data->reset_gpio,
				      data->active_low ? 1 : 0);
		if (data->delays[0])
			msleep(DIV_ROUND_UP(data->delays[0], 1000));

		gpio_set_value(data->reset_gpio, data->active_low ? 0 : 1);
		if (data->delays[1])
			msleep(DIV_ROUND_UP(data->delays[1], 1000));

		gpio_set_value(data->reset_gpio, data->active_low ? 1 : 0);
		if (data->delays[2])
			msleep(DIV_ROUND_UP(data->delays[2], 1000));
	}
#endif

	if (data->phy_reset) {
		netdev_dbg(ndev, "stmmac_mdio_reset: calling phy_reset\n");
		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. To be updated for GMAC4
	 * if needed.
	 */
	if (!priv->plat->has_gmac4)
		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;
	struct stmmac_priv *priv = netdev_priv(ndev);
	struct stmmac_mdio_bus_data *mdio_bus_data = priv->plat->mdio_bus_data;
	struct device_node *mdio_node = priv->plat->mdio_node;
	struct device *dev = ndev->dev.parent;
	int addr, found, max_addr;

	if (!mdio_bus_data)
		return 0;

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

	if (mdio_bus_data->irqs)
		memcpy(new_bus->irq, mdio_bus_data->irqs, sizeof(new_bus->irq));

#ifdef CONFIG_OF
	if (priv->device->of_node)
		mdio_bus_data->reset_gpio = -1;
#endif

	new_bus->name = "stmmac";

	if (priv->plat->has_xgmac) {
		new_bus->read = &stmmac_xgmac2_mdio_read;
		new_bus->write = &stmmac_xgmac2_mdio_write;

		/* Right now only C22 phys are supported */
		max_addr = MII_XGMAC_MAX_C22ADDR + 1;

		/* Check if DT specified an unsupported phy addr */
		if (priv->plat->phy_addr > MII_XGMAC_MAX_C22ADDR)
			dev_err(dev, "Unsupported phy_addr (max=%d)\n",
					MII_XGMAC_MAX_C22ADDR);
	} else {
		new_bus->read = &stmmac_mdio_read;
		new_bus->write = &stmmac_mdio_write;
		max_addr = PHY_MAX_ADDR;
	}

	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->phy_mask = mdio_bus_data->phy_mask;
	new_bus->parent = priv->device;

	err = of_mdiobus_register(new_bus, mdio_node);
	if (err != 0) {
		dev_err(dev, "Cannot register the MDIO bus\n");
		goto bus_register_fail;
	}

	if (priv->plat->phy_node || mdio_node)
		goto bus_register_done;

	found = 0;
	for (addr = 0; addr < max_addr; addr++) {
		struct phy_device *phydev = mdiobus_get_phy(new_bus, addr);

		if (!phydev)
			continue;

		/*
		 * If an IRQ was provided to be assigned after
		 * the bus probe, do it here.
		 */
		if (!mdio_bus_data->irqs &&
		    (mdio_bus_data->probed_phy_irq > 0)) {
			new_bus->irq[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;

		phy_attached_info(phydev);
		found = 1;
	}

	if (!found && !mdio_node) {
		dev_warn(dev, "No PHY found\n");
		mdiobus_unregister(new_bus);
		mdiobus_free(new_bus);
		return -ENODEV;
	}

bus_register_done:
	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;
}