xref: /linux/drivers/net/mdio.c (revision 5bdef865eb358b6f3760e25e591ae115e9eeddef)
1 /*
2  * mdio.c: Generic support for MDIO-compatible transceivers
3  * Copyright 2006-2009 Solarflare Communications Inc.
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms of the GNU General Public License version 2 as published
7  * by the Free Software Foundation, incorporated herein by reference.
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/capability.h>
12 #include <linux/errno.h>
13 #include <linux/ethtool.h>
14 #include <linux/mdio.h>
15 #include <linux/module.h>
16 
17 MODULE_DESCRIPTION("Generic support for MDIO-compatible transceivers");
18 MODULE_AUTHOR("Copyright 2006-2009 Solarflare Communications Inc.");
19 MODULE_LICENSE("GPL");
20 
21 /**
22  * mdio45_probe - probe for an MDIO (clause 45) device
23  * @mdio: MDIO interface
24  * @prtad: Expected PHY address
25  *
26  * This sets @prtad and @mmds in the MDIO interface if successful.
27  * Returns 0 on success, negative on error.
28  */
29 int mdio45_probe(struct mdio_if_info *mdio, int prtad)
30 {
31 	int mmd, stat2, devs1, devs2;
32 
33 	/* Assume PHY must have at least one of PMA/PMD, WIS, PCS, PHY
34 	 * XS or DTE XS; give up if none is present. */
35 	for (mmd = 1; mmd <= 5; mmd++) {
36 		/* Is this MMD present? */
37 		stat2 = mdio->mdio_read(mdio->dev, prtad, mmd, MDIO_STAT2);
38 		if (stat2 < 0 ||
39 		    (stat2 & MDIO_STAT2_DEVPRST) != MDIO_STAT2_DEVPRST_VAL)
40 			continue;
41 
42 		/* It should tell us about all the other MMDs */
43 		devs1 = mdio->mdio_read(mdio->dev, prtad, mmd, MDIO_DEVS1);
44 		devs2 = mdio->mdio_read(mdio->dev, prtad, mmd, MDIO_DEVS2);
45 		if (devs1 < 0 || devs2 < 0)
46 			continue;
47 
48 		mdio->prtad = prtad;
49 		mdio->mmds = devs1 | (devs2 << 16);
50 		return 0;
51 	}
52 
53 	return -ENODEV;
54 }
55 EXPORT_SYMBOL(mdio45_probe);
56 
57 /**
58  * mdio_set_flag - set or clear flag in an MDIO register
59  * @mdio: MDIO interface
60  * @prtad: PHY address
61  * @devad: MMD address
62  * @addr: Register address
63  * @mask: Mask for flag (single bit set)
64  * @sense: New value of flag
65  *
66  * This debounces changes: it does not write the register if the flag
67  * already has the proper value.  Returns 0 on success, negative on error.
68  */
69 int mdio_set_flag(const struct mdio_if_info *mdio,
70 		  int prtad, int devad, u16 addr, int mask,
71 		  bool sense)
72 {
73 	int old_val = mdio->mdio_read(mdio->dev, prtad, devad, addr);
74 	int new_val;
75 
76 	if (old_val < 0)
77 		return old_val;
78 	if (sense)
79 		new_val = old_val | mask;
80 	else
81 		new_val = old_val & ~mask;
82 	if (old_val == new_val)
83 		return 0;
84 	return mdio->mdio_write(mdio->dev, prtad, devad, addr, new_val);
85 }
86 EXPORT_SYMBOL(mdio_set_flag);
87 
88 /**
89  * mdio_link_ok - is link status up/OK
90  * @mdio: MDIO interface
91  * @mmd_mask: Mask for MMDs to check
92  *
93  * Returns 1 if the PHY reports link status up/OK, 0 otherwise.
94  * @mmd_mask is normally @mdio->mmds, but if loopback is enabled
95  * the MMDs being bypassed should be excluded from the mask.
96  */
97 int mdio45_links_ok(const struct mdio_if_info *mdio, u32 mmd_mask)
98 {
99 	int devad, reg;
100 
101 	if (!mmd_mask) {
102 		/* Use absence of XGMII faults in lieu of link state */
103 		reg = mdio->mdio_read(mdio->dev, mdio->prtad,
104 				      MDIO_MMD_PHYXS, MDIO_STAT2);
105 		return reg >= 0 && !(reg & MDIO_STAT2_RXFAULT);
106 	}
107 
108 	for (devad = 0; mmd_mask; devad++) {
109 		if (mmd_mask & (1 << devad)) {
110 			mmd_mask &= ~(1 << devad);
111 
112 			/* Read twice because link state is latched and a
113 			 * read moves the current state into the register */
114 			mdio->mdio_read(mdio->dev, mdio->prtad,
115 					devad, MDIO_STAT1);
116 			reg = mdio->mdio_read(mdio->dev, mdio->prtad,
117 					      devad, MDIO_STAT1);
118 			if (reg < 0 || !(reg & MDIO_STAT1_LSTATUS))
119 				return false;
120 		}
121 	}
122 
123 	return true;
124 }
125 EXPORT_SYMBOL(mdio45_links_ok);
126 
127 /**
128  * mdio45_nway_restart - restart auto-negotiation for this interface
129  * @mdio: MDIO interface
130  *
131  * Returns 0 on success, negative on error.
132  */
133 int mdio45_nway_restart(const struct mdio_if_info *mdio)
134 {
135 	if (!(mdio->mmds & MDIO_DEVS_AN))
136 		return -EOPNOTSUPP;
137 
138 	mdio_set_flag(mdio, mdio->prtad, MDIO_MMD_AN, MDIO_CTRL1,
139 		      MDIO_AN_CTRL1_RESTART, true);
140 	return 0;
141 }
142 EXPORT_SYMBOL(mdio45_nway_restart);
143 
144 static u32 mdio45_get_an(const struct mdio_if_info *mdio, u16 addr)
145 {
146 	u32 result = 0;
147 	int reg;
148 
149 	reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_AN, addr);
150 	if (reg & ADVERTISE_10HALF)
151 		result |= ADVERTISED_10baseT_Half;
152 	if (reg & ADVERTISE_10FULL)
153 		result |= ADVERTISED_10baseT_Full;
154 	if (reg & ADVERTISE_100HALF)
155 		result |= ADVERTISED_100baseT_Half;
156 	if (reg & ADVERTISE_100FULL)
157 		result |= ADVERTISED_100baseT_Full;
158 	return result;
159 }
160 
161 /**
162  * mdio45_ethtool_gset_npage - get settings for ETHTOOL_GSET
163  * @mdio: MDIO interface
164  * @ecmd: Ethtool request structure
165  * @npage_adv: Modes currently advertised on next pages
166  * @npage_lpa: Modes advertised by link partner on next pages
167  *
168  * Since the CSRs for auto-negotiation using next pages are not fully
169  * standardised, this function does not attempt to decode them.  The
170  * caller must pass them in.
171  */
172 void mdio45_ethtool_gset_npage(const struct mdio_if_info *mdio,
173 			       struct ethtool_cmd *ecmd,
174 			       u32 npage_adv, u32 npage_lpa)
175 {
176 	int reg;
177 
178 	ecmd->transceiver = XCVR_INTERNAL;
179 	ecmd->phy_address = mdio->prtad;
180 	ecmd->mdio_support =
181 		mdio->mode_support & (MDIO_SUPPORTS_C45 | MDIO_SUPPORTS_C22);
182 
183 	reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
184 			      MDIO_CTRL2);
185 	switch (reg & MDIO_PMA_CTRL2_TYPE) {
186 	case MDIO_PMA_CTRL2_10GBT:
187 	case MDIO_PMA_CTRL2_1000BT:
188 	case MDIO_PMA_CTRL2_100BTX:
189 	case MDIO_PMA_CTRL2_10BT:
190 		ecmd->port = PORT_TP;
191 		ecmd->supported = SUPPORTED_TP;
192 		reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
193 				      MDIO_SPEED);
194 		if (reg & MDIO_SPEED_10G)
195 			ecmd->supported |= SUPPORTED_10000baseT_Full;
196 		if (reg & MDIO_PMA_SPEED_1000)
197 			ecmd->supported |= (SUPPORTED_1000baseT_Full |
198 					    SUPPORTED_1000baseT_Half);
199 		if (reg & MDIO_PMA_SPEED_100)
200 			ecmd->supported |= (SUPPORTED_100baseT_Full |
201 					    SUPPORTED_100baseT_Half);
202 		if (reg & MDIO_PMA_SPEED_10)
203 			ecmd->supported |= (SUPPORTED_10baseT_Full |
204 					    SUPPORTED_10baseT_Half);
205 		ecmd->advertising = ADVERTISED_TP;
206 		break;
207 
208 	case MDIO_PMA_CTRL2_10GBCX4:
209 		ecmd->port = PORT_OTHER;
210 		ecmd->supported = 0;
211 		ecmd->advertising = 0;
212 		break;
213 
214 	case MDIO_PMA_CTRL2_10GBKX4:
215 	case MDIO_PMA_CTRL2_10GBKR:
216 	case MDIO_PMA_CTRL2_1000BKX:
217 		ecmd->port = PORT_OTHER;
218 		ecmd->supported = SUPPORTED_Backplane;
219 		reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
220 				      MDIO_PMA_EXTABLE);
221 		if (reg & MDIO_PMA_EXTABLE_10GBKX4)
222 			ecmd->supported |= SUPPORTED_10000baseKX4_Full;
223 		if (reg & MDIO_PMA_EXTABLE_10GBKR)
224 			ecmd->supported |= SUPPORTED_10000baseKR_Full;
225 		if (reg & MDIO_PMA_EXTABLE_1000BKX)
226 			ecmd->supported |= SUPPORTED_1000baseKX_Full;
227 		reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
228 				      MDIO_PMA_10GBR_FECABLE);
229 		if (reg & MDIO_PMA_10GBR_FECABLE_ABLE)
230 			ecmd->supported |= SUPPORTED_10000baseR_FEC;
231 		ecmd->advertising = ADVERTISED_Backplane;
232 		break;
233 
234 	/* All the other defined modes are flavours of optical */
235 	default:
236 		ecmd->port = PORT_FIBRE;
237 		ecmd->supported = SUPPORTED_FIBRE;
238 		ecmd->advertising = ADVERTISED_FIBRE;
239 		break;
240 	}
241 
242 	if (mdio->mmds & MDIO_DEVS_AN) {
243 		ecmd->supported |= SUPPORTED_Autoneg;
244 		reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_AN,
245 				      MDIO_CTRL1);
246 		if (reg & MDIO_AN_CTRL1_ENABLE) {
247 			ecmd->autoneg = AUTONEG_ENABLE;
248 			ecmd->advertising |=
249 				ADVERTISED_Autoneg |
250 				mdio45_get_an(mdio, MDIO_AN_ADVERTISE) |
251 				npage_adv;
252 		} else {
253 			ecmd->autoneg = AUTONEG_DISABLE;
254 		}
255 	} else {
256 		ecmd->autoneg = AUTONEG_DISABLE;
257 	}
258 
259 	if (ecmd->autoneg) {
260 		u32 modes = 0;
261 		int an_stat = mdio->mdio_read(mdio->dev, mdio->prtad,
262 					      MDIO_MMD_AN, MDIO_STAT1);
263 
264 		/* If AN is complete and successful, report best common
265 		 * mode, otherwise report best advertised mode. */
266 		if (an_stat & MDIO_AN_STAT1_COMPLETE) {
267 			ecmd->lp_advertising =
268 				mdio45_get_an(mdio, MDIO_AN_LPA) | npage_lpa;
269 			if (an_stat & MDIO_AN_STAT1_LPABLE)
270 				ecmd->lp_advertising |= ADVERTISED_Autoneg;
271 			modes = ecmd->advertising & ecmd->lp_advertising;
272 		}
273 		if ((modes & ~ADVERTISED_Autoneg) == 0)
274 			modes = ecmd->advertising;
275 
276 		if (modes & (ADVERTISED_10000baseT_Full |
277 			     ADVERTISED_10000baseKX4_Full |
278 			     ADVERTISED_10000baseKR_Full)) {
279 			ecmd->speed = SPEED_10000;
280 			ecmd->duplex = DUPLEX_FULL;
281 		} else if (modes & (ADVERTISED_1000baseT_Full |
282 				    ADVERTISED_1000baseT_Half |
283 				    ADVERTISED_1000baseKX_Full)) {
284 			ecmd->speed = SPEED_1000;
285 			ecmd->duplex = !(modes & ADVERTISED_1000baseT_Half);
286 		} else if (modes & (ADVERTISED_100baseT_Full |
287 				    ADVERTISED_100baseT_Half)) {
288 			ecmd->speed = SPEED_100;
289 			ecmd->duplex = !!(modes & ADVERTISED_100baseT_Full);
290 		} else {
291 			ecmd->speed = SPEED_10;
292 			ecmd->duplex = !!(modes & ADVERTISED_10baseT_Full);
293 		}
294 	} else {
295 		/* Report forced settings */
296 		reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
297 				      MDIO_CTRL1);
298 		ecmd->speed = (((reg & MDIO_PMA_CTRL1_SPEED1000) ? 100 : 1) *
299 			       ((reg & MDIO_PMA_CTRL1_SPEED100) ? 100 : 10));
300 		ecmd->duplex = (reg & MDIO_CTRL1_FULLDPLX ||
301 				ecmd->speed == SPEED_10000);
302 	}
303 
304 	/* 10GBASE-T MDI/MDI-X */
305 	if (ecmd->port == PORT_TP && ecmd->speed == SPEED_10000) {
306 		switch (mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
307 					MDIO_PMA_10GBT_SWAPPOL)) {
308 		case MDIO_PMA_10GBT_SWAPPOL_ABNX | MDIO_PMA_10GBT_SWAPPOL_CDNX:
309 			ecmd->eth_tp_mdix = ETH_TP_MDI;
310 			break;
311 		case 0:
312 			ecmd->eth_tp_mdix = ETH_TP_MDI_X;
313 			break;
314 		default:
315 			/* It's complicated... */
316 			ecmd->eth_tp_mdix = ETH_TP_MDI_INVALID;
317 			break;
318 		}
319 	}
320 }
321 EXPORT_SYMBOL(mdio45_ethtool_gset_npage);
322 
323 /**
324  * mdio45_ethtool_spauseparam_an - set auto-negotiated pause parameters
325  * @mdio: MDIO interface
326  * @ecmd: Ethtool request structure
327  *
328  * This function assumes that the PHY has an auto-negotiation MMD.  It
329  * will enable and disable advertising of flow control as appropriate.
330  */
331 void mdio45_ethtool_spauseparam_an(const struct mdio_if_info *mdio,
332 				   const struct ethtool_pauseparam *ecmd)
333 {
334 	int adv, old_adv;
335 
336 	WARN_ON(!(mdio->mmds & MDIO_DEVS_AN));
337 
338 	old_adv = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_AN,
339 				  MDIO_AN_ADVERTISE);
340 	adv = old_adv & ~(ADVERTISE_PAUSE_CAP | ADVERTISE_PAUSE_ASYM);
341 	if (ecmd->autoneg)
342 		adv |= mii_advertise_flowctrl(
343 			(ecmd->rx_pause ? FLOW_CTRL_RX : 0) |
344 			(ecmd->tx_pause ? FLOW_CTRL_TX : 0));
345 	if (adv != old_adv) {
346 		mdio->mdio_write(mdio->dev, mdio->prtad, MDIO_MMD_AN,
347 				 MDIO_AN_ADVERTISE, adv);
348 		mdio45_nway_restart(mdio);
349 	}
350 }
351 EXPORT_SYMBOL(mdio45_ethtool_spauseparam_an);
352 
353 /**
354  * mdio_mii_ioctl - MII ioctl interface for MDIO (clause 22 or 45) PHYs
355  * @mdio: MDIO interface
356  * @mii_data: MII ioctl data structure
357  * @cmd: MII ioctl command
358  *
359  * Returns 0 on success, negative on error.
360  */
361 int mdio_mii_ioctl(const struct mdio_if_info *mdio,
362 		   struct mii_ioctl_data *mii_data, int cmd)
363 {
364 	int prtad, devad;
365 	u16 addr = mii_data->reg_num;
366 
367 	/* Validate/convert cmd to one of SIOC{G,S}MIIREG */
368 	switch (cmd) {
369 	case SIOCGMIIPHY:
370 		if (mdio->prtad == MDIO_PRTAD_NONE)
371 			return -EOPNOTSUPP;
372 		mii_data->phy_id = mdio->prtad;
373 		cmd = SIOCGMIIREG;
374 		break;
375 	case SIOCGMIIREG:
376 		break;
377 	case SIOCSMIIREG:
378 		if (!capable(CAP_NET_ADMIN))
379 			return -EPERM;
380 		break;
381 	default:
382 		return -EOPNOTSUPP;
383 	}
384 
385 	/* Validate/convert phy_id */
386 	if ((mdio->mode_support & MDIO_SUPPORTS_C45) &&
387 	    mdio_phy_id_is_c45(mii_data->phy_id)) {
388 		prtad = mdio_phy_id_prtad(mii_data->phy_id);
389 		devad = mdio_phy_id_devad(mii_data->phy_id);
390 	} else if ((mdio->mode_support & MDIO_SUPPORTS_C22) &&
391 		   mii_data->phy_id < 0x20) {
392 		prtad = mii_data->phy_id;
393 		devad = MDIO_DEVAD_NONE;
394 		addr &= 0x1f;
395 	} else if ((mdio->mode_support & MDIO_EMULATE_C22) &&
396 		   mdio->prtad != MDIO_PRTAD_NONE &&
397 		   mii_data->phy_id == mdio->prtad) {
398 		/* Remap commonly-used MII registers. */
399 		prtad = mdio->prtad;
400 		switch (addr) {
401 		case MII_BMCR:
402 		case MII_BMSR:
403 		case MII_PHYSID1:
404 		case MII_PHYSID2:
405 			devad = __ffs(mdio->mmds);
406 			break;
407 		case MII_ADVERTISE:
408 		case MII_LPA:
409 			if (!(mdio->mmds & MDIO_DEVS_AN))
410 				return -EINVAL;
411 			devad = MDIO_MMD_AN;
412 			if (addr == MII_ADVERTISE)
413 				addr = MDIO_AN_ADVERTISE;
414 			else
415 				addr = MDIO_AN_LPA;
416 			break;
417 		default:
418 			return -EINVAL;
419 		}
420 	} else {
421 		return -EINVAL;
422 	}
423 
424 	if (cmd == SIOCGMIIREG) {
425 		int rc = mdio->mdio_read(mdio->dev, prtad, devad, addr);
426 		if (rc < 0)
427 			return rc;
428 		mii_data->val_out = rc;
429 		return 0;
430 	} else {
431 		return mdio->mdio_write(mdio->dev, prtad, devad, addr,
432 					mii_data->val_in);
433 	}
434 }
435 EXPORT_SYMBOL(mdio_mii_ioctl);
436