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
17MODULE_DESCRIPTION("Generic support for MDIO-compatible transceivers");
18MODULE_AUTHOR("Copyright 2006-2009 Solarflare Communications Inc.");
19MODULE_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 */
29int 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}
55EXPORT_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 */
69int 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}
86EXPORT_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 */
97int 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			/* Reset the latched status and fault flags */
113			mdio->mdio_read(mdio->dev, mdio->prtad,
114					devad, MDIO_STAT1);
115			if (devad == MDIO_MMD_PMAPMD || devad == MDIO_MMD_PCS ||
116			    devad == MDIO_MMD_PHYXS || devad == MDIO_MMD_DTEXS)
117				mdio->mdio_read(mdio->dev, mdio->prtad,
118						devad, MDIO_STAT2);
119
120			/* Check the current status and fault flags */
121			reg = mdio->mdio_read(mdio->dev, mdio->prtad,
122					      devad, MDIO_STAT1);
123			if (reg < 0 ||
124			    (reg & (MDIO_STAT1_FAULT | MDIO_STAT1_LSTATUS)) !=
125			    MDIO_STAT1_LSTATUS)
126				return false;
127		}
128	}
129
130	return true;
131}
132EXPORT_SYMBOL(mdio45_links_ok);
133
134/**
135 * mdio45_nway_restart - restart auto-negotiation for this interface
136 * @mdio: MDIO interface
137 *
138 * Returns 0 on success, negative on error.
139 */
140int mdio45_nway_restart(const struct mdio_if_info *mdio)
141{
142	if (!(mdio->mmds & MDIO_DEVS_AN))
143		return -EOPNOTSUPP;
144
145	mdio_set_flag(mdio, mdio->prtad, MDIO_MMD_AN, MDIO_CTRL1,
146		      MDIO_AN_CTRL1_RESTART, true);
147	return 0;
148}
149EXPORT_SYMBOL(mdio45_nway_restart);
150
151static u32 mdio45_get_an(const struct mdio_if_info *mdio, u16 addr)
152{
153	u32 result = 0;
154	int reg;
155
156	reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_AN, addr);
157	if (reg & ADVERTISE_10HALF)
158		result |= ADVERTISED_10baseT_Half;
159	if (reg & ADVERTISE_10FULL)
160		result |= ADVERTISED_10baseT_Full;
161	if (reg & ADVERTISE_100HALF)
162		result |= ADVERTISED_100baseT_Half;
163	if (reg & ADVERTISE_100FULL)
164		result |= ADVERTISED_100baseT_Full;
165	if (reg & ADVERTISE_PAUSE_CAP)
166		result |= ADVERTISED_Pause;
167	if (reg & ADVERTISE_PAUSE_ASYM)
168		result |= ADVERTISED_Asym_Pause;
169	return result;
170}
171
172/**
173 * mdio45_ethtool_gset_npage - get settings for ETHTOOL_GSET
174 * @mdio: MDIO interface
175 * @ecmd: Ethtool request structure
176 * @npage_adv: Modes currently advertised on next pages
177 * @npage_lpa: Modes advertised by link partner on next pages
178 *
179 * The @ecmd parameter is expected to have been cleared before calling
180 * mdio45_ethtool_gset_npage().
181 *
182 * Since the CSRs for auto-negotiation using next pages are not fully
183 * standardised, this function does not attempt to decode them.  The
184 * caller must pass them in.
185 */
186void mdio45_ethtool_gset_npage(const struct mdio_if_info *mdio,
187			       struct ethtool_cmd *ecmd,
188			       u32 npage_adv, u32 npage_lpa)
189{
190	int reg;
191	u32 speed;
192
193	BUILD_BUG_ON(MDIO_SUPPORTS_C22 != ETH_MDIO_SUPPORTS_C22);
194	BUILD_BUG_ON(MDIO_SUPPORTS_C45 != ETH_MDIO_SUPPORTS_C45);
195
196	ecmd->transceiver = XCVR_INTERNAL;
197	ecmd->phy_address = mdio->prtad;
198	ecmd->mdio_support =
199		mdio->mode_support & (MDIO_SUPPORTS_C45 | MDIO_SUPPORTS_C22);
200
201	reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
202			      MDIO_CTRL2);
203	switch (reg & MDIO_PMA_CTRL2_TYPE) {
204	case MDIO_PMA_CTRL2_10GBT:
205	case MDIO_PMA_CTRL2_1000BT:
206	case MDIO_PMA_CTRL2_100BTX:
207	case MDIO_PMA_CTRL2_10BT:
208		ecmd->port = PORT_TP;
209		ecmd->supported = SUPPORTED_TP;
210		reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
211				      MDIO_SPEED);
212		if (reg & MDIO_SPEED_10G)
213			ecmd->supported |= SUPPORTED_10000baseT_Full;
214		if (reg & MDIO_PMA_SPEED_1000)
215			ecmd->supported |= (SUPPORTED_1000baseT_Full |
216					    SUPPORTED_1000baseT_Half);
217		if (reg & MDIO_PMA_SPEED_100)
218			ecmd->supported |= (SUPPORTED_100baseT_Full |
219					    SUPPORTED_100baseT_Half);
220		if (reg & MDIO_PMA_SPEED_10)
221			ecmd->supported |= (SUPPORTED_10baseT_Full |
222					    SUPPORTED_10baseT_Half);
223		ecmd->advertising = ADVERTISED_TP;
224		break;
225
226	case MDIO_PMA_CTRL2_10GBCX4:
227		ecmd->port = PORT_OTHER;
228		ecmd->supported = 0;
229		ecmd->advertising = 0;
230		break;
231
232	case MDIO_PMA_CTRL2_10GBKX4:
233	case MDIO_PMA_CTRL2_10GBKR:
234	case MDIO_PMA_CTRL2_1000BKX:
235		ecmd->port = PORT_OTHER;
236		ecmd->supported = SUPPORTED_Backplane;
237		reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
238				      MDIO_PMA_EXTABLE);
239		if (reg & MDIO_PMA_EXTABLE_10GBKX4)
240			ecmd->supported |= SUPPORTED_10000baseKX4_Full;
241		if (reg & MDIO_PMA_EXTABLE_10GBKR)
242			ecmd->supported |= SUPPORTED_10000baseKR_Full;
243		if (reg & MDIO_PMA_EXTABLE_1000BKX)
244			ecmd->supported |= SUPPORTED_1000baseKX_Full;
245		reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
246				      MDIO_PMA_10GBR_FECABLE);
247		if (reg & MDIO_PMA_10GBR_FECABLE_ABLE)
248			ecmd->supported |= SUPPORTED_10000baseR_FEC;
249		ecmd->advertising = ADVERTISED_Backplane;
250		break;
251
252	/* All the other defined modes are flavours of optical */
253	default:
254		ecmd->port = PORT_FIBRE;
255		ecmd->supported = SUPPORTED_FIBRE;
256		ecmd->advertising = ADVERTISED_FIBRE;
257		break;
258	}
259
260	if (mdio->mmds & MDIO_DEVS_AN) {
261		ecmd->supported |= SUPPORTED_Autoneg;
262		reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_AN,
263				      MDIO_CTRL1);
264		if (reg & MDIO_AN_CTRL1_ENABLE) {
265			ecmd->autoneg = AUTONEG_ENABLE;
266			ecmd->advertising |=
267				ADVERTISED_Autoneg |
268				mdio45_get_an(mdio, MDIO_AN_ADVERTISE) |
269				npage_adv;
270		} else {
271			ecmd->autoneg = AUTONEG_DISABLE;
272		}
273	} else {
274		ecmd->autoneg = AUTONEG_DISABLE;
275	}
276
277	if (ecmd->autoneg) {
278		u32 modes = 0;
279		int an_stat = mdio->mdio_read(mdio->dev, mdio->prtad,
280					      MDIO_MMD_AN, MDIO_STAT1);
281
282		/* If AN is complete and successful, report best common
283		 * mode, otherwise report best advertised mode. */
284		if (an_stat & MDIO_AN_STAT1_COMPLETE) {
285			ecmd->lp_advertising =
286				mdio45_get_an(mdio, MDIO_AN_LPA) | npage_lpa;
287			if (an_stat & MDIO_AN_STAT1_LPABLE)
288				ecmd->lp_advertising |= ADVERTISED_Autoneg;
289			modes = ecmd->advertising & ecmd->lp_advertising;
290		}
291		if ((modes & ~ADVERTISED_Autoneg) == 0)
292			modes = ecmd->advertising;
293
294		if (modes & (ADVERTISED_10000baseT_Full |
295			     ADVERTISED_10000baseKX4_Full |
296			     ADVERTISED_10000baseKR_Full)) {
297			speed = SPEED_10000;
298			ecmd->duplex = DUPLEX_FULL;
299		} else if (modes & (ADVERTISED_1000baseT_Full |
300				    ADVERTISED_1000baseT_Half |
301				    ADVERTISED_1000baseKX_Full)) {
302			speed = SPEED_1000;
303			ecmd->duplex = !(modes & ADVERTISED_1000baseT_Half);
304		} else if (modes & (ADVERTISED_100baseT_Full |
305				    ADVERTISED_100baseT_Half)) {
306			speed = SPEED_100;
307			ecmd->duplex = !!(modes & ADVERTISED_100baseT_Full);
308		} else {
309			speed = SPEED_10;
310			ecmd->duplex = !!(modes & ADVERTISED_10baseT_Full);
311		}
312	} else {
313		/* Report forced settings */
314		reg = mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
315				      MDIO_CTRL1);
316		speed = (((reg & MDIO_PMA_CTRL1_SPEED1000) ? 100 : 1)
317			 * ((reg & MDIO_PMA_CTRL1_SPEED100) ? 100 : 10));
318		ecmd->duplex = (reg & MDIO_CTRL1_FULLDPLX ||
319				speed == SPEED_10000);
320	}
321
322	ethtool_cmd_speed_set(ecmd, speed);
323
324	/* 10GBASE-T MDI/MDI-X */
325	if (ecmd->port == PORT_TP
326	    && (ethtool_cmd_speed(ecmd) == SPEED_10000)) {
327		switch (mdio->mdio_read(mdio->dev, mdio->prtad, MDIO_MMD_PMAPMD,
328					MDIO_PMA_10GBT_SWAPPOL)) {
329		case MDIO_PMA_10GBT_SWAPPOL_ABNX | MDIO_PMA_10GBT_SWAPPOL_CDNX:
330			ecmd->eth_tp_mdix = ETH_TP_MDI;
331			break;
332		case 0:
333			ecmd->eth_tp_mdix = ETH_TP_MDI_X;
334			break;
335		default:
336			/* It's complicated... */
337			ecmd->eth_tp_mdix = ETH_TP_MDI_INVALID;
338			break;
339		}
340	}
341}
342EXPORT_SYMBOL(mdio45_ethtool_gset_npage);
343
344/**
345 * mdio_mii_ioctl - MII ioctl interface for MDIO (clause 22 or 45) PHYs
346 * @mdio: MDIO interface
347 * @mii_data: MII ioctl data structure
348 * @cmd: MII ioctl command
349 *
350 * Returns 0 on success, negative on error.
351 */
352int mdio_mii_ioctl(const struct mdio_if_info *mdio,
353		   struct mii_ioctl_data *mii_data, int cmd)
354{
355	int prtad, devad;
356	u16 addr = mii_data->reg_num;
357
358	/* Validate/convert cmd to one of SIOC{G,S}MIIREG */
359	switch (cmd) {
360	case SIOCGMIIPHY:
361		if (mdio->prtad == MDIO_PRTAD_NONE)
362			return -EOPNOTSUPP;
363		mii_data->phy_id = mdio->prtad;
364		cmd = SIOCGMIIREG;
365		break;
366	case SIOCGMIIREG:
367	case SIOCSMIIREG:
368		break;
369	default:
370		return -EOPNOTSUPP;
371	}
372
373	/* Validate/convert phy_id */
374	if ((mdio->mode_support & MDIO_SUPPORTS_C45) &&
375	    mdio_phy_id_is_c45(mii_data->phy_id)) {
376		prtad = mdio_phy_id_prtad(mii_data->phy_id);
377		devad = mdio_phy_id_devad(mii_data->phy_id);
378	} else if ((mdio->mode_support & MDIO_SUPPORTS_C22) &&
379		   mii_data->phy_id < 0x20) {
380		prtad = mii_data->phy_id;
381		devad = MDIO_DEVAD_NONE;
382		addr &= 0x1f;
383	} else if ((mdio->mode_support & MDIO_EMULATE_C22) &&
384		   mdio->prtad != MDIO_PRTAD_NONE &&
385		   mii_data->phy_id == mdio->prtad) {
386		/* Remap commonly-used MII registers. */
387		prtad = mdio->prtad;
388		switch (addr) {
389		case MII_BMCR:
390		case MII_BMSR:
391		case MII_PHYSID1:
392		case MII_PHYSID2:
393			devad = __ffs(mdio->mmds);
394			break;
395		case MII_ADVERTISE:
396		case MII_LPA:
397			if (!(mdio->mmds & MDIO_DEVS_AN))
398				return -EINVAL;
399			devad = MDIO_MMD_AN;
400			if (addr == MII_ADVERTISE)
401				addr = MDIO_AN_ADVERTISE;
402			else
403				addr = MDIO_AN_LPA;
404			break;
405		default:
406			return -EINVAL;
407		}
408	} else {
409		return -EINVAL;
410	}
411
412	if (cmd == SIOCGMIIREG) {
413		int rc = mdio->mdio_read(mdio->dev, prtad, devad, addr);
414		if (rc < 0)
415			return rc;
416		mii_data->val_out = rc;
417		return 0;
418	} else {
419		return mdio->mdio_write(mdio->dev, prtad, devad, addr,
420					mii_data->val_in);
421	}
422}
423EXPORT_SYMBOL(mdio_mii_ioctl);
424