xref: /linux/drivers/net/ethernet/intel/igc/igc_phy.c (revision b7df4cc3a088a8ce6973c96731bc792dbf54ce28)
1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c)  2018 Intel Corporation */
3 
4 #include <linux/bitfield.h>
5 #include "igc_phy.h"
6 
7 /**
8  * igc_check_reset_block - Check if PHY reset is blocked
9  * @hw: pointer to the HW structure
10  *
11  * Read the PHY management control register and check whether a PHY reset
12  * is blocked.  If a reset is not blocked return 0, otherwise
13  * return IGC_ERR_BLK_PHY_RESET (12).
14  */
15 s32 igc_check_reset_block(struct igc_hw *hw)
16 {
17 	u32 manc;
18 
19 	manc = rd32(IGC_MANC);
20 
21 	return (manc & IGC_MANC_BLK_PHY_RST_ON_IDE) ?
22 		IGC_ERR_BLK_PHY_RESET : 0;
23 }
24 
25 /**
26  * igc_get_phy_id - Retrieve the PHY ID and revision
27  * @hw: pointer to the HW structure
28  *
29  * Reads the PHY registers and stores the PHY ID and possibly the PHY
30  * revision in the hardware structure.
31  */
32 s32 igc_get_phy_id(struct igc_hw *hw)
33 {
34 	struct igc_phy_info *phy = &hw->phy;
35 	s32 ret_val = 0;
36 	u16 phy_id;
37 
38 	ret_val = phy->ops.read_reg(hw, PHY_ID1, &phy_id);
39 	if (ret_val)
40 		goto out;
41 
42 	phy->id = (u32)(phy_id << 16);
43 	usleep_range(200, 500);
44 	ret_val = phy->ops.read_reg(hw, PHY_ID2, &phy_id);
45 	if (ret_val)
46 		goto out;
47 
48 	phy->id |= (u32)(phy_id & PHY_REVISION_MASK);
49 	phy->revision = (u32)(phy_id & ~PHY_REVISION_MASK);
50 
51 out:
52 	return ret_val;
53 }
54 
55 /**
56  * igc_phy_has_link - Polls PHY for link
57  * @hw: pointer to the HW structure
58  * @iterations: number of times to poll for link
59  * @usec_interval: delay between polling attempts
60  * @success: pointer to whether polling was successful or not
61  *
62  * Polls the PHY status register for link, 'iterations' number of times.
63  */
64 s32 igc_phy_has_link(struct igc_hw *hw, u32 iterations,
65 		     u32 usec_interval, bool *success)
66 {
67 	u16 i, phy_status;
68 	s32 ret_val = 0;
69 
70 	for (i = 0; i < iterations; i++) {
71 		/* Some PHYs require the PHY_STATUS register to be read
72 		 * twice due to the link bit being sticky.  No harm doing
73 		 * it across the board.
74 		 */
75 		ret_val = hw->phy.ops.read_reg(hw, PHY_STATUS, &phy_status);
76 		if (ret_val && usec_interval > 0) {
77 			/* If the first read fails, another entity may have
78 			 * ownership of the resources, wait and try again to
79 			 * see if they have relinquished the resources yet.
80 			 */
81 			if (usec_interval >= 1000)
82 				mdelay(usec_interval / 1000);
83 			else
84 				udelay(usec_interval);
85 		}
86 		ret_val = hw->phy.ops.read_reg(hw, PHY_STATUS, &phy_status);
87 		if (ret_val)
88 			break;
89 		if (phy_status & MII_SR_LINK_STATUS)
90 			break;
91 		if (usec_interval >= 1000)
92 			mdelay(usec_interval / 1000);
93 		else
94 			udelay(usec_interval);
95 	}
96 
97 	*success = (i < iterations) ? true : false;
98 
99 	return ret_val;
100 }
101 
102 /**
103  * igc_power_up_phy_copper - Restore copper link in case of PHY power down
104  * @hw: pointer to the HW structure
105  *
106  * In the case of a PHY power down to save power, or to turn off link during a
107  * driver unload, restore the link to previous settings.
108  */
109 void igc_power_up_phy_copper(struct igc_hw *hw)
110 {
111 	u16 mii_reg = 0;
112 
113 	/* The PHY will retain its settings across a power down/up cycle */
114 	hw->phy.ops.read_reg(hw, PHY_CONTROL, &mii_reg);
115 	mii_reg &= ~MII_CR_POWER_DOWN;
116 	hw->phy.ops.write_reg(hw, PHY_CONTROL, mii_reg);
117 }
118 
119 /**
120  * igc_power_down_phy_copper - Power down copper PHY
121  * @hw: pointer to the HW structure
122  *
123  * Power down PHY to save power when interface is down and wake on lan
124  * is not enabled.
125  */
126 void igc_power_down_phy_copper(struct igc_hw *hw)
127 {
128 	u16 mii_reg = 0;
129 
130 	/* The PHY will retain its settings across a power down/up cycle */
131 	hw->phy.ops.read_reg(hw, PHY_CONTROL, &mii_reg);
132 	mii_reg |= MII_CR_POWER_DOWN;
133 	hw->phy.ops.write_reg(hw, PHY_CONTROL, mii_reg);
134 	usleep_range(1000, 2000);
135 }
136 
137 /**
138  * igc_check_downshift - Checks whether a downshift in speed occurred
139  * @hw: pointer to the HW structure
140  *
141  * A downshift is detected by querying the PHY link health.
142  */
143 void igc_check_downshift(struct igc_hw *hw)
144 {
145 	struct igc_phy_info *phy = &hw->phy;
146 
147 	/* speed downshift not supported */
148 	phy->speed_downgraded = false;
149 }
150 
151 /**
152  * igc_phy_hw_reset - PHY hardware reset
153  * @hw: pointer to the HW structure
154  *
155  * Verify the reset block is not blocking us from resetting.  Acquire
156  * semaphore (if necessary) and read/set/write the device control reset
157  * bit in the PHY.  Wait the appropriate delay time for the device to
158  * reset and release the semaphore (if necessary).
159  */
160 s32 igc_phy_hw_reset(struct igc_hw *hw)
161 {
162 	struct igc_phy_info *phy = &hw->phy;
163 	u32 phpm = 0, timeout = 10000;
164 	s32  ret_val;
165 	u32 ctrl;
166 
167 	ret_val = igc_check_reset_block(hw);
168 	if (ret_val) {
169 		ret_val = 0;
170 		goto out;
171 	}
172 
173 	ret_val = phy->ops.acquire(hw);
174 	if (ret_val)
175 		goto out;
176 
177 	phpm = rd32(IGC_I225_PHPM);
178 
179 	ctrl = rd32(IGC_CTRL);
180 	wr32(IGC_CTRL, ctrl | IGC_CTRL_PHY_RST);
181 	wrfl();
182 
183 	udelay(phy->reset_delay_us);
184 
185 	wr32(IGC_CTRL, ctrl);
186 	wrfl();
187 
188 	/* SW should guarantee 100us for the completion of the PHY reset */
189 	usleep_range(100, 150);
190 	do {
191 		phpm = rd32(IGC_I225_PHPM);
192 		timeout--;
193 		udelay(1);
194 	} while (!(phpm & IGC_PHY_RST_COMP) && timeout);
195 
196 	if (!timeout)
197 		hw_dbg("Timeout is expired after a phy reset\n");
198 
199 	usleep_range(100, 150);
200 
201 	phy->ops.release(hw);
202 
203 out:
204 	return ret_val;
205 }
206 
207 /**
208  * igc_phy_setup_autoneg - Configure PHY for auto-negotiation
209  * @hw: pointer to the HW structure
210  *
211  * Reads the MII auto-neg advertisement register and/or the 1000T control
212  * register and if the PHY is already setup for auto-negotiation, then
213  * return successful.  Otherwise, setup advertisement and flow control to
214  * the appropriate values for the wanted auto-negotiation.
215  */
216 static s32 igc_phy_setup_autoneg(struct igc_hw *hw)
217 {
218 	struct igc_phy_info *phy = &hw->phy;
219 	u16 aneg_multigbt_an_ctrl = 0;
220 	u16 mii_1000t_ctrl_reg = 0;
221 	u16 mii_autoneg_adv_reg;
222 	s32 ret_val;
223 
224 	phy->autoneg_advertised &= phy->autoneg_mask;
225 
226 	/* Read the MII Auto-Neg Advertisement Register (Address 4). */
227 	ret_val = phy->ops.read_reg(hw, PHY_AUTONEG_ADV, &mii_autoneg_adv_reg);
228 	if (ret_val)
229 		return ret_val;
230 
231 	if (phy->autoneg_mask & ADVERTISE_1000_FULL) {
232 		/* Read the MII 1000Base-T Control Register (Address 9). */
233 		ret_val = phy->ops.read_reg(hw, PHY_1000T_CTRL,
234 					    &mii_1000t_ctrl_reg);
235 		if (ret_val)
236 			return ret_val;
237 	}
238 
239 	if (phy->autoneg_mask & ADVERTISE_2500_FULL) {
240 		/* Read the MULTI GBT AN Control Register - reg 7.32 */
241 		ret_val = phy->ops.read_reg(hw, (STANDARD_AN_REG_MASK <<
242 					    MMD_DEVADDR_SHIFT) |
243 					    ANEG_MULTIGBT_AN_CTRL,
244 					    &aneg_multigbt_an_ctrl);
245 
246 		if (ret_val)
247 			return ret_val;
248 	}
249 
250 	/* Need to parse both autoneg_advertised and fc and set up
251 	 * the appropriate PHY registers.  First we will parse for
252 	 * autoneg_advertised software override.  Since we can advertise
253 	 * a plethora of combinations, we need to check each bit
254 	 * individually.
255 	 */
256 
257 	/* First we clear all the 10/100 mb speed bits in the Auto-Neg
258 	 * Advertisement Register (Address 4) and the 1000 mb speed bits in
259 	 * the  1000Base-T Control Register (Address 9).
260 	 */
261 	mii_autoneg_adv_reg &= ~(NWAY_AR_100TX_FD_CAPS |
262 				 NWAY_AR_100TX_HD_CAPS |
263 				 NWAY_AR_10T_FD_CAPS   |
264 				 NWAY_AR_10T_HD_CAPS);
265 	mii_1000t_ctrl_reg &= ~(CR_1000T_HD_CAPS | CR_1000T_FD_CAPS);
266 
267 	hw_dbg("autoneg_advertised %x\n", phy->autoneg_advertised);
268 
269 	/* Do we want to advertise 10 Mb Half Duplex? */
270 	if (phy->autoneg_advertised & ADVERTISE_10_HALF) {
271 		hw_dbg("Advertise 10mb Half duplex\n");
272 		mii_autoneg_adv_reg |= NWAY_AR_10T_HD_CAPS;
273 	}
274 
275 	/* Do we want to advertise 10 Mb Full Duplex? */
276 	if (phy->autoneg_advertised & ADVERTISE_10_FULL) {
277 		hw_dbg("Advertise 10mb Full duplex\n");
278 		mii_autoneg_adv_reg |= NWAY_AR_10T_FD_CAPS;
279 	}
280 
281 	/* Do we want to advertise 100 Mb Half Duplex? */
282 	if (phy->autoneg_advertised & ADVERTISE_100_HALF) {
283 		hw_dbg("Advertise 100mb Half duplex\n");
284 		mii_autoneg_adv_reg |= NWAY_AR_100TX_HD_CAPS;
285 	}
286 
287 	/* Do we want to advertise 100 Mb Full Duplex? */
288 	if (phy->autoneg_advertised & ADVERTISE_100_FULL) {
289 		hw_dbg("Advertise 100mb Full duplex\n");
290 		mii_autoneg_adv_reg |= NWAY_AR_100TX_FD_CAPS;
291 	}
292 
293 	/* We do not allow the Phy to advertise 1000 Mb Half Duplex */
294 	if (phy->autoneg_advertised & ADVERTISE_1000_HALF)
295 		hw_dbg("Advertise 1000mb Half duplex request denied!\n");
296 
297 	/* Do we want to advertise 1000 Mb Full Duplex? */
298 	if (phy->autoneg_advertised & ADVERTISE_1000_FULL) {
299 		hw_dbg("Advertise 1000mb Full duplex\n");
300 		mii_1000t_ctrl_reg |= CR_1000T_FD_CAPS;
301 	}
302 
303 	/* We do not allow the Phy to advertise 2500 Mb Half Duplex */
304 	if (phy->autoneg_advertised & ADVERTISE_2500_HALF)
305 		hw_dbg("Advertise 2500mb Half duplex request denied!\n");
306 
307 	/* Do we want to advertise 2500 Mb Full Duplex? */
308 	if (phy->autoneg_advertised & ADVERTISE_2500_FULL) {
309 		hw_dbg("Advertise 2500mb Full duplex\n");
310 		aneg_multigbt_an_ctrl |= CR_2500T_FD_CAPS;
311 	} else {
312 		aneg_multigbt_an_ctrl &= ~CR_2500T_FD_CAPS;
313 	}
314 
315 	/* Check for a software override of the flow control settings, and
316 	 * setup the PHY advertisement registers accordingly.  If
317 	 * auto-negotiation is enabled, then software will have to set the
318 	 * "PAUSE" bits to the correct value in the Auto-Negotiation
319 	 * Advertisement Register (PHY_AUTONEG_ADV) and re-start auto-
320 	 * negotiation.
321 	 *
322 	 * The possible values of the "fc" parameter are:
323 	 *      0:  Flow control is completely disabled
324 	 *      1:  Rx flow control is enabled (we can receive pause frames
325 	 *          but not send pause frames).
326 	 *      2:  Tx flow control is enabled (we can send pause frames
327 	 *          but we do not support receiving pause frames).
328 	 *      3:  Both Rx and Tx flow control (symmetric) are enabled.
329 	 *  other:  No software override.  The flow control configuration
330 	 *          in the EEPROM is used.
331 	 */
332 	switch (hw->fc.current_mode) {
333 	case igc_fc_none:
334 		/* Flow control (Rx & Tx) is completely disabled by a
335 		 * software over-ride.
336 		 */
337 		mii_autoneg_adv_reg &= ~(NWAY_AR_ASM_DIR | NWAY_AR_PAUSE);
338 		break;
339 	case igc_fc_rx_pause:
340 		/* Rx Flow control is enabled, and Tx Flow control is
341 		 * disabled, by a software over-ride.
342 		 *
343 		 * Since there really isn't a way to advertise that we are
344 		 * capable of Rx Pause ONLY, we will advertise that we
345 		 * support both symmetric and asymmetric Rx PAUSE.  Later
346 		 * (in igc_config_fc_after_link_up) we will disable the
347 		 * hw's ability to send PAUSE frames.
348 		 */
349 		mii_autoneg_adv_reg |= (NWAY_AR_ASM_DIR | NWAY_AR_PAUSE);
350 		break;
351 	case igc_fc_tx_pause:
352 		/* Tx Flow control is enabled, and Rx Flow control is
353 		 * disabled, by a software over-ride.
354 		 */
355 		mii_autoneg_adv_reg |= NWAY_AR_ASM_DIR;
356 		mii_autoneg_adv_reg &= ~NWAY_AR_PAUSE;
357 		break;
358 	case igc_fc_full:
359 		/* Flow control (both Rx and Tx) is enabled by a software
360 		 * over-ride.
361 		 */
362 		mii_autoneg_adv_reg |= (NWAY_AR_ASM_DIR | NWAY_AR_PAUSE);
363 		break;
364 	default:
365 		hw_dbg("Flow control param set incorrectly\n");
366 		return -IGC_ERR_CONFIG;
367 	}
368 
369 	ret_val = phy->ops.write_reg(hw, PHY_AUTONEG_ADV, mii_autoneg_adv_reg);
370 	if (ret_val)
371 		return ret_val;
372 
373 	hw_dbg("Auto-Neg Advertising %x\n", mii_autoneg_adv_reg);
374 
375 	if (phy->autoneg_mask & ADVERTISE_1000_FULL)
376 		ret_val = phy->ops.write_reg(hw, PHY_1000T_CTRL,
377 					     mii_1000t_ctrl_reg);
378 
379 	if (phy->autoneg_mask & ADVERTISE_2500_FULL)
380 		ret_val = phy->ops.write_reg(hw,
381 					     (STANDARD_AN_REG_MASK <<
382 					     MMD_DEVADDR_SHIFT) |
383 					     ANEG_MULTIGBT_AN_CTRL,
384 					     aneg_multigbt_an_ctrl);
385 
386 	return ret_val;
387 }
388 
389 /**
390  * igc_wait_autoneg - Wait for auto-neg completion
391  * @hw: pointer to the HW structure
392  *
393  * Waits for auto-negotiation to complete or for the auto-negotiation time
394  * limit to expire, which ever happens first.
395  */
396 static s32 igc_wait_autoneg(struct igc_hw *hw)
397 {
398 	u16 i, phy_status;
399 	s32 ret_val = 0;
400 
401 	/* Break after autoneg completes or PHY_AUTO_NEG_LIMIT expires. */
402 	for (i = PHY_AUTO_NEG_LIMIT; i > 0; i--) {
403 		ret_val = hw->phy.ops.read_reg(hw, PHY_STATUS, &phy_status);
404 		if (ret_val)
405 			break;
406 		ret_val = hw->phy.ops.read_reg(hw, PHY_STATUS, &phy_status);
407 		if (ret_val)
408 			break;
409 		if (phy_status & MII_SR_AUTONEG_COMPLETE)
410 			break;
411 		msleep(100);
412 	}
413 
414 	/* PHY_AUTO_NEG_TIME expiration doesn't guarantee auto-negotiation
415 	 * has completed.
416 	 */
417 	return ret_val;
418 }
419 
420 /**
421  * igc_copper_link_autoneg - Setup/Enable autoneg for copper link
422  * @hw: pointer to the HW structure
423  *
424  * Performs initial bounds checking on autoneg advertisement parameter, then
425  * configure to advertise the full capability.  Setup the PHY to autoneg
426  * and restart the negotiation process between the link partner.  If
427  * autoneg_wait_to_complete, then wait for autoneg to complete before exiting.
428  */
429 static s32 igc_copper_link_autoneg(struct igc_hw *hw)
430 {
431 	struct igc_phy_info *phy = &hw->phy;
432 	u16 phy_ctrl;
433 	s32 ret_val;
434 
435 	/* Perform some bounds checking on the autoneg advertisement
436 	 * parameter.
437 	 */
438 	phy->autoneg_advertised &= phy->autoneg_mask;
439 
440 	/* If autoneg_advertised is zero, we assume it was not defaulted
441 	 * by the calling code so we set to advertise full capability.
442 	 */
443 	if (phy->autoneg_advertised == 0)
444 		phy->autoneg_advertised = phy->autoneg_mask;
445 
446 	hw_dbg("Reconfiguring auto-neg advertisement params\n");
447 	ret_val = igc_phy_setup_autoneg(hw);
448 	if (ret_val) {
449 		hw_dbg("Error Setting up Auto-Negotiation\n");
450 		goto out;
451 	}
452 	hw_dbg("Restarting Auto-Neg\n");
453 
454 	/* Restart auto-negotiation by setting the Auto Neg Enable bit and
455 	 * the Auto Neg Restart bit in the PHY control register.
456 	 */
457 	ret_val = phy->ops.read_reg(hw, PHY_CONTROL, &phy_ctrl);
458 	if (ret_val)
459 		goto out;
460 
461 	phy_ctrl |= (MII_CR_AUTO_NEG_EN | MII_CR_RESTART_AUTO_NEG);
462 	ret_val = phy->ops.write_reg(hw, PHY_CONTROL, phy_ctrl);
463 	if (ret_val)
464 		goto out;
465 
466 	/* Does the user want to wait for Auto-Neg to complete here, or
467 	 * check at a later time (for example, callback routine).
468 	 */
469 	if (phy->autoneg_wait_to_complete) {
470 		ret_val = igc_wait_autoneg(hw);
471 		if (ret_val) {
472 			hw_dbg("Error while waiting for autoneg to complete\n");
473 			goto out;
474 		}
475 	}
476 
477 	hw->mac.get_link_status = true;
478 
479 out:
480 	return ret_val;
481 }
482 
483 /**
484  * igc_setup_copper_link - Configure copper link settings
485  * @hw: pointer to the HW structure
486  *
487  * Calls the appropriate function to configure the link for auto-neg or forced
488  * speed and duplex.  Then we check for link, once link is established calls
489  * to configure collision distance and flow control are called.  If link is
490  * not established, we return -IGC_ERR_PHY (-2).
491  */
492 s32 igc_setup_copper_link(struct igc_hw *hw)
493 {
494 	s32 ret_val = 0;
495 	bool link;
496 
497 	if (hw->mac.autoneg) {
498 		/* Setup autoneg and flow control advertisement and perform
499 		 * autonegotiation.
500 		 */
501 		ret_val = igc_copper_link_autoneg(hw);
502 		if (ret_val)
503 			goto out;
504 	} else {
505 		/* PHY will be set to 10H, 10F, 100H or 100F
506 		 * depending on user settings.
507 		 */
508 		hw_dbg("Forcing Speed and Duplex\n");
509 		ret_val = hw->phy.ops.force_speed_duplex(hw);
510 		if (ret_val) {
511 			hw_dbg("Error Forcing Speed and Duplex\n");
512 			goto out;
513 		}
514 	}
515 
516 	/* Check link status. Wait up to 100 microseconds for link to become
517 	 * valid.
518 	 */
519 	ret_val = igc_phy_has_link(hw, COPPER_LINK_UP_LIMIT, 10, &link);
520 	if (ret_val)
521 		goto out;
522 
523 	if (link) {
524 		hw_dbg("Valid link established!!!\n");
525 		igc_config_collision_dist(hw);
526 		ret_val = igc_config_fc_after_link_up(hw);
527 	} else {
528 		hw_dbg("Unable to establish link!!!\n");
529 	}
530 
531 out:
532 	return ret_val;
533 }
534 
535 /**
536  * igc_read_phy_reg_mdic - Read MDI control register
537  * @hw: pointer to the HW structure
538  * @offset: register offset to be read
539  * @data: pointer to the read data
540  *
541  * Reads the MDI control register in the PHY at offset and stores the
542  * information read to data.
543  */
544 static s32 igc_read_phy_reg_mdic(struct igc_hw *hw, u32 offset, u16 *data)
545 {
546 	struct igc_phy_info *phy = &hw->phy;
547 	u32 i, mdic = 0;
548 	s32 ret_val = 0;
549 
550 	if (offset > MAX_PHY_REG_ADDRESS) {
551 		hw_dbg("PHY Address %d is out of range\n", offset);
552 		ret_val = -IGC_ERR_PARAM;
553 		goto out;
554 	}
555 
556 	/* Set up Op-code, Phy Address, and register offset in the MDI
557 	 * Control register.  The MAC will take care of interfacing with the
558 	 * PHY to retrieve the desired data.
559 	 */
560 	mdic = ((offset << IGC_MDIC_REG_SHIFT) |
561 		(phy->addr << IGC_MDIC_PHY_SHIFT) |
562 		(IGC_MDIC_OP_READ));
563 
564 	wr32(IGC_MDIC, mdic);
565 
566 	/* Poll the ready bit to see if the MDI read completed
567 	 * Increasing the time out as testing showed failures with
568 	 * the lower time out
569 	 */
570 	for (i = 0; i < IGC_GEN_POLL_TIMEOUT; i++) {
571 		udelay(50);
572 		mdic = rd32(IGC_MDIC);
573 		if (mdic & IGC_MDIC_READY)
574 			break;
575 	}
576 	if (!(mdic & IGC_MDIC_READY)) {
577 		hw_dbg("MDI Read did not complete\n");
578 		ret_val = -IGC_ERR_PHY;
579 		goto out;
580 	}
581 	if (mdic & IGC_MDIC_ERROR) {
582 		hw_dbg("MDI Error\n");
583 		ret_val = -IGC_ERR_PHY;
584 		goto out;
585 	}
586 	*data = (u16)mdic;
587 
588 out:
589 	return ret_val;
590 }
591 
592 /**
593  * igc_write_phy_reg_mdic - Write MDI control register
594  * @hw: pointer to the HW structure
595  * @offset: register offset to write to
596  * @data: data to write to register at offset
597  *
598  * Writes data to MDI control register in the PHY at offset.
599  */
600 static s32 igc_write_phy_reg_mdic(struct igc_hw *hw, u32 offset, u16 data)
601 {
602 	struct igc_phy_info *phy = &hw->phy;
603 	u32 i, mdic = 0;
604 	s32 ret_val = 0;
605 
606 	if (offset > MAX_PHY_REG_ADDRESS) {
607 		hw_dbg("PHY Address %d is out of range\n", offset);
608 		ret_val = -IGC_ERR_PARAM;
609 		goto out;
610 	}
611 
612 	/* Set up Op-code, Phy Address, and register offset in the MDI
613 	 * Control register.  The MAC will take care of interfacing with the
614 	 * PHY to write the desired data.
615 	 */
616 	mdic = (((u32)data) |
617 		(offset << IGC_MDIC_REG_SHIFT) |
618 		(phy->addr << IGC_MDIC_PHY_SHIFT) |
619 		(IGC_MDIC_OP_WRITE));
620 
621 	wr32(IGC_MDIC, mdic);
622 
623 	/* Poll the ready bit to see if the MDI read completed
624 	 * Increasing the time out as testing showed failures with
625 	 * the lower time out
626 	 */
627 	for (i = 0; i < IGC_GEN_POLL_TIMEOUT; i++) {
628 		udelay(50);
629 		mdic = rd32(IGC_MDIC);
630 		if (mdic & IGC_MDIC_READY)
631 			break;
632 	}
633 	if (!(mdic & IGC_MDIC_READY)) {
634 		hw_dbg("MDI Write did not complete\n");
635 		ret_val = -IGC_ERR_PHY;
636 		goto out;
637 	}
638 	if (mdic & IGC_MDIC_ERROR) {
639 		hw_dbg("MDI Error\n");
640 		ret_val = -IGC_ERR_PHY;
641 		goto out;
642 	}
643 
644 out:
645 	return ret_val;
646 }
647 
648 /**
649  * __igc_access_xmdio_reg - Read/write XMDIO register
650  * @hw: pointer to the HW structure
651  * @address: XMDIO address to program
652  * @dev_addr: device address to program
653  * @data: pointer to value to read/write from/to the XMDIO address
654  * @read: boolean flag to indicate read or write
655  */
656 static s32 __igc_access_xmdio_reg(struct igc_hw *hw, u16 address,
657 				  u8 dev_addr, u16 *data, bool read)
658 {
659 	s32 ret_val;
660 
661 	ret_val = hw->phy.ops.write_reg(hw, IGC_MMDAC, dev_addr);
662 	if (ret_val)
663 		return ret_val;
664 
665 	ret_val = hw->phy.ops.write_reg(hw, IGC_MMDAAD, address);
666 	if (ret_val)
667 		return ret_val;
668 
669 	ret_val = hw->phy.ops.write_reg(hw, IGC_MMDAC, IGC_MMDAC_FUNC_DATA |
670 					dev_addr);
671 	if (ret_val)
672 		return ret_val;
673 
674 	if (read)
675 		ret_val = hw->phy.ops.read_reg(hw, IGC_MMDAAD, data);
676 	else
677 		ret_val = hw->phy.ops.write_reg(hw, IGC_MMDAAD, *data);
678 	if (ret_val)
679 		return ret_val;
680 
681 	/* Recalibrate the device back to 0 */
682 	ret_val = hw->phy.ops.write_reg(hw, IGC_MMDAC, 0);
683 	if (ret_val)
684 		return ret_val;
685 
686 	return ret_val;
687 }
688 
689 /**
690  * igc_read_xmdio_reg - Read XMDIO register
691  * @hw: pointer to the HW structure
692  * @addr: XMDIO address to program
693  * @dev_addr: device address to program
694  * @data: value to be read from the EMI address
695  */
696 static s32 igc_read_xmdio_reg(struct igc_hw *hw, u16 addr,
697 			      u8 dev_addr, u16 *data)
698 {
699 	return __igc_access_xmdio_reg(hw, addr, dev_addr, data, true);
700 }
701 
702 /**
703  * igc_write_xmdio_reg - Write XMDIO register
704  * @hw: pointer to the HW structure
705  * @addr: XMDIO address to program
706  * @dev_addr: device address to program
707  * @data: value to be written to the XMDIO address
708  */
709 static s32 igc_write_xmdio_reg(struct igc_hw *hw, u16 addr,
710 			       u8 dev_addr, u16 data)
711 {
712 	return __igc_access_xmdio_reg(hw, addr, dev_addr, &data, false);
713 }
714 
715 /**
716  * igc_write_phy_reg_gpy - Write GPY PHY register
717  * @hw: pointer to the HW structure
718  * @offset: register offset to write to
719  * @data: data to write at register offset
720  *
721  * Acquires semaphore, if necessary, then writes the data to PHY register
722  * at the offset. Release any acquired semaphores before exiting.
723  */
724 s32 igc_write_phy_reg_gpy(struct igc_hw *hw, u32 offset, u16 data)
725 {
726 	u8 dev_addr = FIELD_GET(GPY_MMD_MASK, offset);
727 	s32 ret_val;
728 
729 	offset = offset & GPY_REG_MASK;
730 
731 	if (!dev_addr) {
732 		ret_val = hw->phy.ops.acquire(hw);
733 		if (ret_val)
734 			return ret_val;
735 		ret_val = igc_write_phy_reg_mdic(hw, offset, data);
736 		hw->phy.ops.release(hw);
737 	} else {
738 		ret_val = igc_write_xmdio_reg(hw, (u16)offset, dev_addr,
739 					      data);
740 	}
741 
742 	return ret_val;
743 }
744 
745 /**
746  * igc_read_phy_reg_gpy - Read GPY PHY register
747  * @hw: pointer to the HW structure
748  * @offset: lower half is register offset to read to
749  * upper half is MMD to use.
750  * @data: data to read at register offset
751  *
752  * Acquires semaphore, if necessary, then reads the data in the PHY register
753  * at the offset. Release any acquired semaphores before exiting.
754  */
755 s32 igc_read_phy_reg_gpy(struct igc_hw *hw, u32 offset, u16 *data)
756 {
757 	u8 dev_addr = FIELD_GET(GPY_MMD_MASK, offset);
758 	s32 ret_val;
759 
760 	offset = offset & GPY_REG_MASK;
761 
762 	if (!dev_addr) {
763 		ret_val = hw->phy.ops.acquire(hw);
764 		if (ret_val)
765 			return ret_val;
766 		ret_val = igc_read_phy_reg_mdic(hw, offset, data);
767 		hw->phy.ops.release(hw);
768 	} else {
769 		ret_val = igc_read_xmdio_reg(hw, (u16)offset, dev_addr,
770 					     data);
771 	}
772 
773 	return ret_val;
774 }
775 
776 /**
777  * igc_read_phy_fw_version - Read gPHY firmware version
778  * @hw: pointer to the HW structure
779  */
780 u16 igc_read_phy_fw_version(struct igc_hw *hw)
781 {
782 	struct igc_phy_info *phy = &hw->phy;
783 	u16 gphy_version = 0;
784 	u16 ret_val;
785 
786 	/* NVM image version is reported as firmware version for i225 device */
787 	ret_val = phy->ops.read_reg(hw, IGC_GPHY_VERSION, &gphy_version);
788 	if (ret_val)
789 		hw_dbg("igc_phy: read wrong gphy version\n");
790 
791 	return gphy_version;
792 }
793