xref: /openbmc/linux/drivers/net/phy/phy-core.c (revision 5b394b2d)
1 /*
2  * Core PHY library, taken from phy.c
3  *
4  * This program is free software; you can redistribute  it and/or modify it
5  * under  the terms of  the GNU General  Public License as published by the
6  * Free Software Foundation;  either version 2 of the  License, or (at your
7  * option) any later version.
8  */
9 #include <linux/export.h>
10 #include <linux/phy.h>
11 
12 const char *phy_speed_to_str(int speed)
13 {
14 	switch (speed) {
15 	case SPEED_10:
16 		return "10Mbps";
17 	case SPEED_100:
18 		return "100Mbps";
19 	case SPEED_1000:
20 		return "1Gbps";
21 	case SPEED_2500:
22 		return "2.5Gbps";
23 	case SPEED_5000:
24 		return "5Gbps";
25 	case SPEED_10000:
26 		return "10Gbps";
27 	case SPEED_14000:
28 		return "14Gbps";
29 	case SPEED_20000:
30 		return "20Gbps";
31 	case SPEED_25000:
32 		return "25Gbps";
33 	case SPEED_40000:
34 		return "40Gbps";
35 	case SPEED_50000:
36 		return "50Gbps";
37 	case SPEED_56000:
38 		return "56Gbps";
39 	case SPEED_100000:
40 		return "100Gbps";
41 	case SPEED_UNKNOWN:
42 		return "Unknown";
43 	default:
44 		return "Unsupported (update phy-core.c)";
45 	}
46 }
47 EXPORT_SYMBOL_GPL(phy_speed_to_str);
48 
49 const char *phy_duplex_to_str(unsigned int duplex)
50 {
51 	if (duplex == DUPLEX_HALF)
52 		return "Half";
53 	if (duplex == DUPLEX_FULL)
54 		return "Full";
55 	if (duplex == DUPLEX_UNKNOWN)
56 		return "Unknown";
57 	return "Unsupported (update phy-core.c)";
58 }
59 EXPORT_SYMBOL_GPL(phy_duplex_to_str);
60 
61 /* A mapping of all SUPPORTED settings to speed/duplex.  This table
62  * must be grouped by speed and sorted in descending match priority
63  * - iow, descending speed. */
64 static const struct phy_setting settings[] = {
65 	{
66 		.speed = SPEED_10000,
67 		.duplex = DUPLEX_FULL,
68 		.bit = ETHTOOL_LINK_MODE_10000baseKR_Full_BIT,
69 	},
70 	{
71 		.speed = SPEED_10000,
72 		.duplex = DUPLEX_FULL,
73 		.bit = ETHTOOL_LINK_MODE_10000baseKX4_Full_BIT,
74 	},
75 	{
76 		.speed = SPEED_10000,
77 		.duplex = DUPLEX_FULL,
78 		.bit = ETHTOOL_LINK_MODE_10000baseT_Full_BIT,
79 	},
80 	{
81 		.speed = SPEED_2500,
82 		.duplex = DUPLEX_FULL,
83 		.bit = ETHTOOL_LINK_MODE_2500baseX_Full_BIT,
84 	},
85 	{
86 		.speed = SPEED_1000,
87 		.duplex = DUPLEX_FULL,
88 		.bit = ETHTOOL_LINK_MODE_1000baseKX_Full_BIT,
89 	},
90 	{
91 		.speed = SPEED_1000,
92 		.duplex = DUPLEX_FULL,
93 		.bit = ETHTOOL_LINK_MODE_1000baseX_Full_BIT,
94 	},
95 	{
96 		.speed = SPEED_1000,
97 		.duplex = DUPLEX_FULL,
98 		.bit = ETHTOOL_LINK_MODE_1000baseT_Full_BIT,
99 	},
100 	{
101 		.speed = SPEED_1000,
102 		.duplex = DUPLEX_HALF,
103 		.bit = ETHTOOL_LINK_MODE_1000baseT_Half_BIT,
104 	},
105 	{
106 		.speed = SPEED_100,
107 		.duplex = DUPLEX_FULL,
108 		.bit = ETHTOOL_LINK_MODE_100baseT_Full_BIT,
109 	},
110 	{
111 		.speed = SPEED_100,
112 		.duplex = DUPLEX_HALF,
113 		.bit = ETHTOOL_LINK_MODE_100baseT_Half_BIT,
114 	},
115 	{
116 		.speed = SPEED_10,
117 		.duplex = DUPLEX_FULL,
118 		.bit = ETHTOOL_LINK_MODE_10baseT_Full_BIT,
119 	},
120 	{
121 		.speed = SPEED_10,
122 		.duplex = DUPLEX_HALF,
123 		.bit = ETHTOOL_LINK_MODE_10baseT_Half_BIT,
124 	},
125 };
126 
127 /**
128  * phy_lookup_setting - lookup a PHY setting
129  * @speed: speed to match
130  * @duplex: duplex to match
131  * @mask: allowed link modes
132  * @maxbit: bit size of link modes
133  * @exact: an exact match is required
134  *
135  * Search the settings array for a setting that matches the speed and
136  * duplex, and which is supported.
137  *
138  * If @exact is unset, either an exact match or %NULL for no match will
139  * be returned.
140  *
141  * If @exact is set, an exact match, the fastest supported setting at
142  * or below the specified speed, the slowest supported setting, or if
143  * they all fail, %NULL will be returned.
144  */
145 const struct phy_setting *
146 phy_lookup_setting(int speed, int duplex, const unsigned long *mask,
147 		   size_t maxbit, bool exact)
148 {
149 	const struct phy_setting *p, *match = NULL, *last = NULL;
150 	int i;
151 
152 	for (i = 0, p = settings; i < ARRAY_SIZE(settings); i++, p++) {
153 		if (p->bit < maxbit && test_bit(p->bit, mask)) {
154 			last = p;
155 			if (p->speed == speed && p->duplex == duplex) {
156 				/* Exact match for speed and duplex */
157 				match = p;
158 				break;
159 			} else if (!exact) {
160 				if (!match && p->speed <= speed)
161 					/* Candidate */
162 					match = p;
163 
164 				if (p->speed < speed)
165 					break;
166 			}
167 		}
168 	}
169 
170 	if (!match && !exact)
171 		match = last;
172 
173 	return match;
174 }
175 EXPORT_SYMBOL_GPL(phy_lookup_setting);
176 
177 size_t phy_speeds(unsigned int *speeds, size_t size,
178 		  unsigned long *mask, size_t maxbit)
179 {
180 	size_t count;
181 	int i;
182 
183 	for (i = 0, count = 0; i < ARRAY_SIZE(settings) && count < size; i++)
184 		if (settings[i].bit < maxbit &&
185 		    test_bit(settings[i].bit, mask) &&
186 		    (count == 0 || speeds[count - 1] != settings[i].speed))
187 			speeds[count++] = settings[i].speed;
188 
189 	return count;
190 }
191 
192 /**
193  * phy_resolve_aneg_linkmode - resolve the advertisements into phy settings
194  * @phydev: The phy_device struct
195  *
196  * Resolve our and the link partner advertisements into their corresponding
197  * speed and duplex. If full duplex was negotiated, extract the pause mode
198  * from the link partner mask.
199  */
200 void phy_resolve_aneg_linkmode(struct phy_device *phydev)
201 {
202 	u32 common = phydev->lp_advertising & phydev->advertising;
203 
204 	if (common & ADVERTISED_10000baseT_Full) {
205 		phydev->speed = SPEED_10000;
206 		phydev->duplex = DUPLEX_FULL;
207 	} else if (common & ADVERTISED_1000baseT_Full) {
208 		phydev->speed = SPEED_1000;
209 		phydev->duplex = DUPLEX_FULL;
210 	} else if (common & ADVERTISED_1000baseT_Half) {
211 		phydev->speed = SPEED_1000;
212 		phydev->duplex = DUPLEX_HALF;
213 	} else if (common & ADVERTISED_100baseT_Full) {
214 		phydev->speed = SPEED_100;
215 		phydev->duplex = DUPLEX_FULL;
216 	} else if (common & ADVERTISED_100baseT_Half) {
217 		phydev->speed = SPEED_100;
218 		phydev->duplex = DUPLEX_HALF;
219 	} else if (common & ADVERTISED_10baseT_Full) {
220 		phydev->speed = SPEED_10;
221 		phydev->duplex = DUPLEX_FULL;
222 	} else if (common & ADVERTISED_10baseT_Half) {
223 		phydev->speed = SPEED_10;
224 		phydev->duplex = DUPLEX_HALF;
225 	}
226 
227 	if (phydev->duplex == DUPLEX_FULL) {
228 		phydev->pause = !!(phydev->lp_advertising & ADVERTISED_Pause);
229 		phydev->asym_pause = !!(phydev->lp_advertising &
230 					ADVERTISED_Asym_Pause);
231 	}
232 }
233 EXPORT_SYMBOL_GPL(phy_resolve_aneg_linkmode);
234 
235 static void mmd_phy_indirect(struct mii_bus *bus, int phy_addr, int devad,
236 			     u16 regnum)
237 {
238 	/* Write the desired MMD Devad */
239 	__mdiobus_write(bus, phy_addr, MII_MMD_CTRL, devad);
240 
241 	/* Write the desired MMD register address */
242 	__mdiobus_write(bus, phy_addr, MII_MMD_DATA, regnum);
243 
244 	/* Select the Function : DATA with no post increment */
245 	__mdiobus_write(bus, phy_addr, MII_MMD_CTRL,
246 			devad | MII_MMD_CTRL_NOINCR);
247 }
248 
249 /**
250  * phy_read_mmd - Convenience function for reading a register
251  * from an MMD on a given PHY.
252  * @phydev: The phy_device struct
253  * @devad: The MMD to read from (0..31)
254  * @regnum: The register on the MMD to read (0..65535)
255  *
256  * Same rules as for phy_read();
257  */
258 int phy_read_mmd(struct phy_device *phydev, int devad, u32 regnum)
259 {
260 	int val;
261 
262 	if (regnum > (u16)~0 || devad > 32)
263 		return -EINVAL;
264 
265 	if (phydev->drv->read_mmd) {
266 		val = phydev->drv->read_mmd(phydev, devad, regnum);
267 	} else if (phydev->is_c45) {
268 		u32 addr = MII_ADDR_C45 | (devad << 16) | (regnum & 0xffff);
269 
270 		val = mdiobus_read(phydev->mdio.bus, phydev->mdio.addr, addr);
271 	} else {
272 		struct mii_bus *bus = phydev->mdio.bus;
273 		int phy_addr = phydev->mdio.addr;
274 
275 		mutex_lock(&bus->mdio_lock);
276 		mmd_phy_indirect(bus, phy_addr, devad, regnum);
277 
278 		/* Read the content of the MMD's selected register */
279 		val = __mdiobus_read(bus, phy_addr, MII_MMD_DATA);
280 		mutex_unlock(&bus->mdio_lock);
281 	}
282 	return val;
283 }
284 EXPORT_SYMBOL(phy_read_mmd);
285 
286 /**
287  * phy_write_mmd - Convenience function for writing a register
288  * on an MMD on a given PHY.
289  * @phydev: The phy_device struct
290  * @devad: The MMD to read from
291  * @regnum: The register on the MMD to read
292  * @val: value to write to @regnum
293  *
294  * Same rules as for phy_write();
295  */
296 int phy_write_mmd(struct phy_device *phydev, int devad, u32 regnum, u16 val)
297 {
298 	int ret;
299 
300 	if (regnum > (u16)~0 || devad > 32)
301 		return -EINVAL;
302 
303 	if (phydev->drv->write_mmd) {
304 		ret = phydev->drv->write_mmd(phydev, devad, regnum, val);
305 	} else if (phydev->is_c45) {
306 		u32 addr = MII_ADDR_C45 | (devad << 16) | (regnum & 0xffff);
307 
308 		ret = mdiobus_write(phydev->mdio.bus, phydev->mdio.addr,
309 				    addr, val);
310 	} else {
311 		struct mii_bus *bus = phydev->mdio.bus;
312 		int phy_addr = phydev->mdio.addr;
313 
314 		mutex_lock(&bus->mdio_lock);
315 		mmd_phy_indirect(bus, phy_addr, devad, regnum);
316 
317 		/* Write the data into MMD's selected register */
318 		__mdiobus_write(bus, phy_addr, MII_MMD_DATA, val);
319 		mutex_unlock(&bus->mdio_lock);
320 
321 		ret = 0;
322 	}
323 	return ret;
324 }
325 EXPORT_SYMBOL(phy_write_mmd);
326 
327 /**
328  * __phy_modify() - Convenience function for modifying a PHY register
329  * @phydev: a pointer to a &struct phy_device
330  * @regnum: register number
331  * @mask: bit mask of bits to clear
332  * @set: bit mask of bits to set
333  *
334  * Unlocked helper function which allows a PHY register to be modified as
335  * new register value = (old register value & ~mask) | set
336  */
337 int __phy_modify(struct phy_device *phydev, u32 regnum, u16 mask, u16 set)
338 {
339 	int ret;
340 
341 	ret = __phy_read(phydev, regnum);
342 	if (ret < 0)
343 		return ret;
344 
345 	ret = __phy_write(phydev, regnum, (ret & ~mask) | set);
346 
347 	return ret < 0 ? ret : 0;
348 }
349 EXPORT_SYMBOL_GPL(__phy_modify);
350 
351 /**
352  * phy_modify - Convenience function for modifying a given PHY register
353  * @phydev: the phy_device struct
354  * @regnum: register number to write
355  * @mask: bit mask of bits to clear
356  * @set: new value of bits set in mask to write to @regnum
357  *
358  * NOTE: MUST NOT be called from interrupt context,
359  * because the bus read/write functions may wait for an interrupt
360  * to conclude the operation.
361  */
362 int phy_modify(struct phy_device *phydev, u32 regnum, u16 mask, u16 set)
363 {
364 	int ret;
365 
366 	mutex_lock(&phydev->mdio.bus->mdio_lock);
367 	ret = __phy_modify(phydev, regnum, mask, set);
368 	mutex_unlock(&phydev->mdio.bus->mdio_lock);
369 
370 	return ret;
371 }
372 EXPORT_SYMBOL_GPL(phy_modify);
373 
374 static int __phy_read_page(struct phy_device *phydev)
375 {
376 	return phydev->drv->read_page(phydev);
377 }
378 
379 static int __phy_write_page(struct phy_device *phydev, int page)
380 {
381 	return phydev->drv->write_page(phydev, page);
382 }
383 
384 /**
385  * phy_save_page() - take the bus lock and save the current page
386  * @phydev: a pointer to a &struct phy_device
387  *
388  * Take the MDIO bus lock, and return the current page number. On error,
389  * returns a negative errno. phy_restore_page() must always be called
390  * after this, irrespective of success or failure of this call.
391  */
392 int phy_save_page(struct phy_device *phydev)
393 {
394 	mutex_lock(&phydev->mdio.bus->mdio_lock);
395 	return __phy_read_page(phydev);
396 }
397 EXPORT_SYMBOL_GPL(phy_save_page);
398 
399 /**
400  * phy_select_page() - take the bus lock, save the current page, and set a page
401  * @phydev: a pointer to a &struct phy_device
402  * @page: desired page
403  *
404  * Take the MDIO bus lock to protect against concurrent access, save the
405  * current PHY page, and set the current page.  On error, returns a
406  * negative errno, otherwise returns the previous page number.
407  * phy_restore_page() must always be called after this, irrespective
408  * of success or failure of this call.
409  */
410 int phy_select_page(struct phy_device *phydev, int page)
411 {
412 	int ret, oldpage;
413 
414 	oldpage = ret = phy_save_page(phydev);
415 	if (ret < 0)
416 		return ret;
417 
418 	if (oldpage != page) {
419 		ret = __phy_write_page(phydev, page);
420 		if (ret < 0)
421 			return ret;
422 	}
423 
424 	return oldpage;
425 }
426 EXPORT_SYMBOL_GPL(phy_select_page);
427 
428 /**
429  * phy_restore_page() - restore the page register and release the bus lock
430  * @phydev: a pointer to a &struct phy_device
431  * @oldpage: the old page, return value from phy_save_page() or phy_select_page()
432  * @ret: operation's return code
433  *
434  * Release the MDIO bus lock, restoring @oldpage if it is a valid page.
435  * This function propagates the earliest error code from the group of
436  * operations.
437  *
438  * Returns:
439  *   @oldpage if it was a negative value, otherwise
440  *   @ret if it was a negative errno value, otherwise
441  *   phy_write_page()'s negative value if it were in error, otherwise
442  *   @ret.
443  */
444 int phy_restore_page(struct phy_device *phydev, int oldpage, int ret)
445 {
446 	int r;
447 
448 	if (oldpage >= 0) {
449 		r = __phy_write_page(phydev, oldpage);
450 
451 		/* Propagate the operation return code if the page write
452 		 * was successful.
453 		 */
454 		if (ret >= 0 && r < 0)
455 			ret = r;
456 	} else {
457 		/* Propagate the phy page selection error code */
458 		ret = oldpage;
459 	}
460 
461 	mutex_unlock(&phydev->mdio.bus->mdio_lock);
462 
463 	return ret;
464 }
465 EXPORT_SYMBOL_GPL(phy_restore_page);
466 
467 /**
468  * phy_read_paged() - Convenience function for reading a paged register
469  * @phydev: a pointer to a &struct phy_device
470  * @page: the page for the phy
471  * @regnum: register number
472  *
473  * Same rules as for phy_read().
474  */
475 int phy_read_paged(struct phy_device *phydev, int page, u32 regnum)
476 {
477 	int ret = 0, oldpage;
478 
479 	oldpage = phy_select_page(phydev, page);
480 	if (oldpage >= 0)
481 		ret = __phy_read(phydev, regnum);
482 
483 	return phy_restore_page(phydev, oldpage, ret);
484 }
485 EXPORT_SYMBOL(phy_read_paged);
486 
487 /**
488  * phy_write_paged() - Convenience function for writing a paged register
489  * @phydev: a pointer to a &struct phy_device
490  * @page: the page for the phy
491  * @regnum: register number
492  * @val: value to write
493  *
494  * Same rules as for phy_write().
495  */
496 int phy_write_paged(struct phy_device *phydev, int page, u32 regnum, u16 val)
497 {
498 	int ret = 0, oldpage;
499 
500 	oldpage = phy_select_page(phydev, page);
501 	if (oldpage >= 0)
502 		ret = __phy_write(phydev, regnum, val);
503 
504 	return phy_restore_page(phydev, oldpage, ret);
505 }
506 EXPORT_SYMBOL(phy_write_paged);
507 
508 /**
509  * phy_modify_paged() - Convenience function for modifying a paged register
510  * @phydev: a pointer to a &struct phy_device
511  * @page: the page for the phy
512  * @regnum: register number
513  * @mask: bit mask of bits to clear
514  * @set: bit mask of bits to set
515  *
516  * Same rules as for phy_read() and phy_write().
517  */
518 int phy_modify_paged(struct phy_device *phydev, int page, u32 regnum,
519 		     u16 mask, u16 set)
520 {
521 	int ret = 0, oldpage;
522 
523 	oldpage = phy_select_page(phydev, page);
524 	if (oldpage >= 0)
525 		ret = __phy_modify(phydev, regnum, mask, set);
526 
527 	return phy_restore_page(phydev, oldpage, ret);
528 }
529 EXPORT_SYMBOL(phy_modify_paged);
530