xref: /openbmc/linux/drivers/ata/libata-sata.c (revision 144679df)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  SATA specific part of ATA helper library
4  *
5  *  Copyright 2003-2004 Red Hat, Inc.  All rights reserved.
6  *  Copyright 2003-2004 Jeff Garzik
7  *  Copyright 2006 Tejun Heo <htejun@gmail.com>
8  */
9 
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <scsi/scsi_cmnd.h>
13 #include <scsi/scsi_device.h>
14 #include <scsi/scsi_eh.h>
15 #include <linux/libata.h>
16 #include <asm/unaligned.h>
17 
18 #include "libata.h"
19 #include "libata-transport.h"
20 
21 /* debounce timing parameters in msecs { interval, duration, timeout } */
22 const unsigned long sata_deb_timing_normal[]		= {   5,  100, 2000 };
23 EXPORT_SYMBOL_GPL(sata_deb_timing_normal);
24 const unsigned long sata_deb_timing_hotplug[]		= {  25,  500, 2000 };
25 EXPORT_SYMBOL_GPL(sata_deb_timing_hotplug);
26 const unsigned long sata_deb_timing_long[]		= { 100, 2000, 5000 };
27 EXPORT_SYMBOL_GPL(sata_deb_timing_long);
28 
29 /**
30  *	sata_scr_valid - test whether SCRs are accessible
31  *	@link: ATA link to test SCR accessibility for
32  *
33  *	Test whether SCRs are accessible for @link.
34  *
35  *	LOCKING:
36  *	None.
37  *
38  *	RETURNS:
39  *	1 if SCRs are accessible, 0 otherwise.
40  */
41 int sata_scr_valid(struct ata_link *link)
42 {
43 	struct ata_port *ap = link->ap;
44 
45 	return (ap->flags & ATA_FLAG_SATA) && ap->ops->scr_read;
46 }
47 EXPORT_SYMBOL_GPL(sata_scr_valid);
48 
49 /**
50  *	sata_scr_read - read SCR register of the specified port
51  *	@link: ATA link to read SCR for
52  *	@reg: SCR to read
53  *	@val: Place to store read value
54  *
55  *	Read SCR register @reg of @link into *@val.  This function is
56  *	guaranteed to succeed if @link is ap->link, the cable type of
57  *	the port is SATA and the port implements ->scr_read.
58  *
59  *	LOCKING:
60  *	None if @link is ap->link.  Kernel thread context otherwise.
61  *
62  *	RETURNS:
63  *	0 on success, negative errno on failure.
64  */
65 int sata_scr_read(struct ata_link *link, int reg, u32 *val)
66 {
67 	if (ata_is_host_link(link)) {
68 		if (sata_scr_valid(link))
69 			return link->ap->ops->scr_read(link, reg, val);
70 		return -EOPNOTSUPP;
71 	}
72 
73 	return sata_pmp_scr_read(link, reg, val);
74 }
75 EXPORT_SYMBOL_GPL(sata_scr_read);
76 
77 /**
78  *	sata_scr_write - write SCR register of the specified port
79  *	@link: ATA link to write SCR for
80  *	@reg: SCR to write
81  *	@val: value to write
82  *
83  *	Write @val to SCR register @reg of @link.  This function is
84  *	guaranteed to succeed if @link is ap->link, the cable type of
85  *	the port is SATA and the port implements ->scr_read.
86  *
87  *	LOCKING:
88  *	None if @link is ap->link.  Kernel thread context otherwise.
89  *
90  *	RETURNS:
91  *	0 on success, negative errno on failure.
92  */
93 int sata_scr_write(struct ata_link *link, int reg, u32 val)
94 {
95 	if (ata_is_host_link(link)) {
96 		if (sata_scr_valid(link))
97 			return link->ap->ops->scr_write(link, reg, val);
98 		return -EOPNOTSUPP;
99 	}
100 
101 	return sata_pmp_scr_write(link, reg, val);
102 }
103 EXPORT_SYMBOL_GPL(sata_scr_write);
104 
105 /**
106  *	sata_scr_write_flush - write SCR register of the specified port and flush
107  *	@link: ATA link to write SCR for
108  *	@reg: SCR to write
109  *	@val: value to write
110  *
111  *	This function is identical to sata_scr_write() except that this
112  *	function performs flush after writing to the register.
113  *
114  *	LOCKING:
115  *	None if @link is ap->link.  Kernel thread context otherwise.
116  *
117  *	RETURNS:
118  *	0 on success, negative errno on failure.
119  */
120 int sata_scr_write_flush(struct ata_link *link, int reg, u32 val)
121 {
122 	if (ata_is_host_link(link)) {
123 		int rc;
124 
125 		if (sata_scr_valid(link)) {
126 			rc = link->ap->ops->scr_write(link, reg, val);
127 			if (rc == 0)
128 				rc = link->ap->ops->scr_read(link, reg, &val);
129 			return rc;
130 		}
131 		return -EOPNOTSUPP;
132 	}
133 
134 	return sata_pmp_scr_write(link, reg, val);
135 }
136 EXPORT_SYMBOL_GPL(sata_scr_write_flush);
137 
138 /**
139  *	ata_tf_to_fis - Convert ATA taskfile to SATA FIS structure
140  *	@tf: Taskfile to convert
141  *	@pmp: Port multiplier port
142  *	@is_cmd: This FIS is for command
143  *	@fis: Buffer into which data will output
144  *
145  *	Converts a standard ATA taskfile to a Serial ATA
146  *	FIS structure (Register - Host to Device).
147  *
148  *	LOCKING:
149  *	Inherited from caller.
150  */
151 void ata_tf_to_fis(const struct ata_taskfile *tf, u8 pmp, int is_cmd, u8 *fis)
152 {
153 	fis[0] = 0x27;			/* Register - Host to Device FIS */
154 	fis[1] = pmp & 0xf;		/* Port multiplier number*/
155 	if (is_cmd)
156 		fis[1] |= (1 << 7);	/* bit 7 indicates Command FIS */
157 
158 	fis[2] = tf->command;
159 	fis[3] = tf->feature;
160 
161 	fis[4] = tf->lbal;
162 	fis[5] = tf->lbam;
163 	fis[6] = tf->lbah;
164 	fis[7] = tf->device;
165 
166 	fis[8] = tf->hob_lbal;
167 	fis[9] = tf->hob_lbam;
168 	fis[10] = tf->hob_lbah;
169 	fis[11] = tf->hob_feature;
170 
171 	fis[12] = tf->nsect;
172 	fis[13] = tf->hob_nsect;
173 	fis[14] = 0;
174 	fis[15] = tf->ctl;
175 
176 	fis[16] = tf->auxiliary & 0xff;
177 	fis[17] = (tf->auxiliary >> 8) & 0xff;
178 	fis[18] = (tf->auxiliary >> 16) & 0xff;
179 	fis[19] = (tf->auxiliary >> 24) & 0xff;
180 }
181 EXPORT_SYMBOL_GPL(ata_tf_to_fis);
182 
183 /**
184  *	ata_tf_from_fis - Convert SATA FIS to ATA taskfile
185  *	@fis: Buffer from which data will be input
186  *	@tf: Taskfile to output
187  *
188  *	Converts a serial ATA FIS structure to a standard ATA taskfile.
189  *
190  *	LOCKING:
191  *	Inherited from caller.
192  */
193 
194 void ata_tf_from_fis(const u8 *fis, struct ata_taskfile *tf)
195 {
196 	tf->status	= fis[2];
197 	tf->error	= fis[3];
198 
199 	tf->lbal	= fis[4];
200 	tf->lbam	= fis[5];
201 	tf->lbah	= fis[6];
202 	tf->device	= fis[7];
203 
204 	tf->hob_lbal	= fis[8];
205 	tf->hob_lbam	= fis[9];
206 	tf->hob_lbah	= fis[10];
207 
208 	tf->nsect	= fis[12];
209 	tf->hob_nsect	= fis[13];
210 }
211 EXPORT_SYMBOL_GPL(ata_tf_from_fis);
212 
213 /**
214  *	sata_link_debounce - debounce SATA phy status
215  *	@link: ATA link to debounce SATA phy status for
216  *	@params: timing parameters { interval, duration, timeout } in msec
217  *	@deadline: deadline jiffies for the operation
218  *
219  *	Make sure SStatus of @link reaches stable state, determined by
220  *	holding the same value where DET is not 1 for @duration polled
221  *	every @interval, before @timeout.  Timeout constraints the
222  *	beginning of the stable state.  Because DET gets stuck at 1 on
223  *	some controllers after hot unplugging, this functions waits
224  *	until timeout then returns 0 if DET is stable at 1.
225  *
226  *	@timeout is further limited by @deadline.  The sooner of the
227  *	two is used.
228  *
229  *	LOCKING:
230  *	Kernel thread context (may sleep)
231  *
232  *	RETURNS:
233  *	0 on success, -errno on failure.
234  */
235 int sata_link_debounce(struct ata_link *link, const unsigned long *params,
236 		       unsigned long deadline)
237 {
238 	unsigned long interval = params[0];
239 	unsigned long duration = params[1];
240 	unsigned long last_jiffies, t;
241 	u32 last, cur;
242 	int rc;
243 
244 	t = ata_deadline(jiffies, params[2]);
245 	if (time_before(t, deadline))
246 		deadline = t;
247 
248 	if ((rc = sata_scr_read(link, SCR_STATUS, &cur)))
249 		return rc;
250 	cur &= 0xf;
251 
252 	last = cur;
253 	last_jiffies = jiffies;
254 
255 	while (1) {
256 		ata_msleep(link->ap, interval);
257 		if ((rc = sata_scr_read(link, SCR_STATUS, &cur)))
258 			return rc;
259 		cur &= 0xf;
260 
261 		/* DET stable? */
262 		if (cur == last) {
263 			if (cur == 1 && time_before(jiffies, deadline))
264 				continue;
265 			if (time_after(jiffies,
266 				       ata_deadline(last_jiffies, duration)))
267 				return 0;
268 			continue;
269 		}
270 
271 		/* unstable, start over */
272 		last = cur;
273 		last_jiffies = jiffies;
274 
275 		/* Check deadline.  If debouncing failed, return
276 		 * -EPIPE to tell upper layer to lower link speed.
277 		 */
278 		if (time_after(jiffies, deadline))
279 			return -EPIPE;
280 	}
281 }
282 EXPORT_SYMBOL_GPL(sata_link_debounce);
283 
284 /**
285  *	sata_link_resume - resume SATA link
286  *	@link: ATA link to resume SATA
287  *	@params: timing parameters { interval, duration, timeout } in msec
288  *	@deadline: deadline jiffies for the operation
289  *
290  *	Resume SATA phy @link and debounce it.
291  *
292  *	LOCKING:
293  *	Kernel thread context (may sleep)
294  *
295  *	RETURNS:
296  *	0 on success, -errno on failure.
297  */
298 int sata_link_resume(struct ata_link *link, const unsigned long *params,
299 		     unsigned long deadline)
300 {
301 	int tries = ATA_LINK_RESUME_TRIES;
302 	u32 scontrol, serror;
303 	int rc;
304 
305 	if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
306 		return rc;
307 
308 	/*
309 	 * Writes to SControl sometimes get ignored under certain
310 	 * controllers (ata_piix SIDPR).  Make sure DET actually is
311 	 * cleared.
312 	 */
313 	do {
314 		scontrol = (scontrol & 0x0f0) | 0x300;
315 		if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
316 			return rc;
317 		/*
318 		 * Some PHYs react badly if SStatus is pounded
319 		 * immediately after resuming.  Delay 200ms before
320 		 * debouncing.
321 		 */
322 		if (!(link->flags & ATA_LFLAG_NO_DEBOUNCE_DELAY))
323 			ata_msleep(link->ap, 200);
324 
325 		/* is SControl restored correctly? */
326 		if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
327 			return rc;
328 	} while ((scontrol & 0xf0f) != 0x300 && --tries);
329 
330 	if ((scontrol & 0xf0f) != 0x300) {
331 		ata_link_warn(link, "failed to resume link (SControl %X)\n",
332 			     scontrol);
333 		return 0;
334 	}
335 
336 	if (tries < ATA_LINK_RESUME_TRIES)
337 		ata_link_warn(link, "link resume succeeded after %d retries\n",
338 			      ATA_LINK_RESUME_TRIES - tries);
339 
340 	if ((rc = sata_link_debounce(link, params, deadline)))
341 		return rc;
342 
343 	/* clear SError, some PHYs require this even for SRST to work */
344 	if (!(rc = sata_scr_read(link, SCR_ERROR, &serror)))
345 		rc = sata_scr_write(link, SCR_ERROR, serror);
346 
347 	return rc != -EINVAL ? rc : 0;
348 }
349 EXPORT_SYMBOL_GPL(sata_link_resume);
350 
351 /**
352  *	sata_link_scr_lpm - manipulate SControl IPM and SPM fields
353  *	@link: ATA link to manipulate SControl for
354  *	@policy: LPM policy to configure
355  *	@spm_wakeup: initiate LPM transition to active state
356  *
357  *	Manipulate the IPM field of the SControl register of @link
358  *	according to @policy.  If @policy is ATA_LPM_MAX_POWER and
359  *	@spm_wakeup is %true, the SPM field is manipulated to wake up
360  *	the link.  This function also clears PHYRDY_CHG before
361  *	returning.
362  *
363  *	LOCKING:
364  *	EH context.
365  *
366  *	RETURNS:
367  *	0 on success, -errno otherwise.
368  */
369 int sata_link_scr_lpm(struct ata_link *link, enum ata_lpm_policy policy,
370 		      bool spm_wakeup)
371 {
372 	struct ata_eh_context *ehc = &link->eh_context;
373 	bool woken_up = false;
374 	u32 scontrol;
375 	int rc;
376 
377 	rc = sata_scr_read(link, SCR_CONTROL, &scontrol);
378 	if (rc)
379 		return rc;
380 
381 	switch (policy) {
382 	case ATA_LPM_MAX_POWER:
383 		/* disable all LPM transitions */
384 		scontrol |= (0x7 << 8);
385 		/* initiate transition to active state */
386 		if (spm_wakeup) {
387 			scontrol |= (0x4 << 12);
388 			woken_up = true;
389 		}
390 		break;
391 	case ATA_LPM_MED_POWER:
392 		/* allow LPM to PARTIAL */
393 		scontrol &= ~(0x1 << 8);
394 		scontrol |= (0x6 << 8);
395 		break;
396 	case ATA_LPM_MED_POWER_WITH_DIPM:
397 	case ATA_LPM_MIN_POWER_WITH_PARTIAL:
398 	case ATA_LPM_MIN_POWER:
399 		if (ata_link_nr_enabled(link) > 0)
400 			/* no restrictions on LPM transitions */
401 			scontrol &= ~(0x7 << 8);
402 		else {
403 			/* empty port, power off */
404 			scontrol &= ~0xf;
405 			scontrol |= (0x1 << 2);
406 		}
407 		break;
408 	default:
409 		WARN_ON(1);
410 	}
411 
412 	rc = sata_scr_write(link, SCR_CONTROL, scontrol);
413 	if (rc)
414 		return rc;
415 
416 	/* give the link time to transit out of LPM state */
417 	if (woken_up)
418 		msleep(10);
419 
420 	/* clear PHYRDY_CHG from SError */
421 	ehc->i.serror &= ~SERR_PHYRDY_CHG;
422 	return sata_scr_write(link, SCR_ERROR, SERR_PHYRDY_CHG);
423 }
424 EXPORT_SYMBOL_GPL(sata_link_scr_lpm);
425 
426 static int __sata_set_spd_needed(struct ata_link *link, u32 *scontrol)
427 {
428 	struct ata_link *host_link = &link->ap->link;
429 	u32 limit, target, spd;
430 
431 	limit = link->sata_spd_limit;
432 
433 	/* Don't configure downstream link faster than upstream link.
434 	 * It doesn't speed up anything and some PMPs choke on such
435 	 * configuration.
436 	 */
437 	if (!ata_is_host_link(link) && host_link->sata_spd)
438 		limit &= (1 << host_link->sata_spd) - 1;
439 
440 	if (limit == UINT_MAX)
441 		target = 0;
442 	else
443 		target = fls(limit);
444 
445 	spd = (*scontrol >> 4) & 0xf;
446 	*scontrol = (*scontrol & ~0xf0) | ((target & 0xf) << 4);
447 
448 	return spd != target;
449 }
450 
451 /**
452  *	sata_set_spd_needed - is SATA spd configuration needed
453  *	@link: Link in question
454  *
455  *	Test whether the spd limit in SControl matches
456  *	@link->sata_spd_limit.  This function is used to determine
457  *	whether hardreset is necessary to apply SATA spd
458  *	configuration.
459  *
460  *	LOCKING:
461  *	Inherited from caller.
462  *
463  *	RETURNS:
464  *	1 if SATA spd configuration is needed, 0 otherwise.
465  */
466 static int sata_set_spd_needed(struct ata_link *link)
467 {
468 	u32 scontrol;
469 
470 	if (sata_scr_read(link, SCR_CONTROL, &scontrol))
471 		return 1;
472 
473 	return __sata_set_spd_needed(link, &scontrol);
474 }
475 
476 /**
477  *	sata_set_spd - set SATA spd according to spd limit
478  *	@link: Link to set SATA spd for
479  *
480  *	Set SATA spd of @link according to sata_spd_limit.
481  *
482  *	LOCKING:
483  *	Inherited from caller.
484  *
485  *	RETURNS:
486  *	0 if spd doesn't need to be changed, 1 if spd has been
487  *	changed.  Negative errno if SCR registers are inaccessible.
488  */
489 int sata_set_spd(struct ata_link *link)
490 {
491 	u32 scontrol;
492 	int rc;
493 
494 	if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
495 		return rc;
496 
497 	if (!__sata_set_spd_needed(link, &scontrol))
498 		return 0;
499 
500 	if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
501 		return rc;
502 
503 	return 1;
504 }
505 EXPORT_SYMBOL_GPL(sata_set_spd);
506 
507 /**
508  *	sata_link_hardreset - reset link via SATA phy reset
509  *	@link: link to reset
510  *	@timing: timing parameters { interval, duration, timeout } in msec
511  *	@deadline: deadline jiffies for the operation
512  *	@online: optional out parameter indicating link onlineness
513  *	@check_ready: optional callback to check link readiness
514  *
515  *	SATA phy-reset @link using DET bits of SControl register.
516  *	After hardreset, link readiness is waited upon using
517  *	ata_wait_ready() if @check_ready is specified.  LLDs are
518  *	allowed to not specify @check_ready and wait itself after this
519  *	function returns.  Device classification is LLD's
520  *	responsibility.
521  *
522  *	*@online is set to one iff reset succeeded and @link is online
523  *	after reset.
524  *
525  *	LOCKING:
526  *	Kernel thread context (may sleep)
527  *
528  *	RETURNS:
529  *	0 on success, -errno otherwise.
530  */
531 int sata_link_hardreset(struct ata_link *link, const unsigned long *timing,
532 			unsigned long deadline,
533 			bool *online, int (*check_ready)(struct ata_link *))
534 {
535 	u32 scontrol;
536 	int rc;
537 
538 	if (online)
539 		*online = false;
540 
541 	if (sata_set_spd_needed(link)) {
542 		/* SATA spec says nothing about how to reconfigure
543 		 * spd.  To be on the safe side, turn off phy during
544 		 * reconfiguration.  This works for at least ICH7 AHCI
545 		 * and Sil3124.
546 		 */
547 		if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
548 			goto out;
549 
550 		scontrol = (scontrol & 0x0f0) | 0x304;
551 
552 		if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
553 			goto out;
554 
555 		sata_set_spd(link);
556 	}
557 
558 	/* issue phy wake/reset */
559 	if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
560 		goto out;
561 
562 	scontrol = (scontrol & 0x0f0) | 0x301;
563 
564 	if ((rc = sata_scr_write_flush(link, SCR_CONTROL, scontrol)))
565 		goto out;
566 
567 	/* Couldn't find anything in SATA I/II specs, but AHCI-1.1
568 	 * 10.4.2 says at least 1 ms.
569 	 */
570 	ata_msleep(link->ap, 1);
571 
572 	/* bring link back */
573 	rc = sata_link_resume(link, timing, deadline);
574 	if (rc)
575 		goto out;
576 	/* if link is offline nothing more to do */
577 	if (ata_phys_link_offline(link))
578 		goto out;
579 
580 	/* Link is online.  From this point, -ENODEV too is an error. */
581 	if (online)
582 		*online = true;
583 
584 	if (sata_pmp_supported(link->ap) && ata_is_host_link(link)) {
585 		/* If PMP is supported, we have to do follow-up SRST.
586 		 * Some PMPs don't send D2H Reg FIS after hardreset if
587 		 * the first port is empty.  Wait only for
588 		 * ATA_TMOUT_PMP_SRST_WAIT.
589 		 */
590 		if (check_ready) {
591 			unsigned long pmp_deadline;
592 
593 			pmp_deadline = ata_deadline(jiffies,
594 						    ATA_TMOUT_PMP_SRST_WAIT);
595 			if (time_after(pmp_deadline, deadline))
596 				pmp_deadline = deadline;
597 			ata_wait_ready(link, pmp_deadline, check_ready);
598 		}
599 		rc = -EAGAIN;
600 		goto out;
601 	}
602 
603 	rc = 0;
604 	if (check_ready)
605 		rc = ata_wait_ready(link, deadline, check_ready);
606  out:
607 	if (rc && rc != -EAGAIN) {
608 		/* online is set iff link is online && reset succeeded */
609 		if (online)
610 			*online = false;
611 		ata_link_err(link, "COMRESET failed (errno=%d)\n", rc);
612 	}
613 	return rc;
614 }
615 EXPORT_SYMBOL_GPL(sata_link_hardreset);
616 
617 /**
618  *	ata_qc_complete_multiple - Complete multiple qcs successfully
619  *	@ap: port in question
620  *	@qc_active: new qc_active mask
621  *
622  *	Complete in-flight commands.  This functions is meant to be
623  *	called from low-level driver's interrupt routine to complete
624  *	requests normally.  ap->qc_active and @qc_active is compared
625  *	and commands are completed accordingly.
626  *
627  *	Always use this function when completing multiple NCQ commands
628  *	from IRQ handlers instead of calling ata_qc_complete()
629  *	multiple times to keep IRQ expect status properly in sync.
630  *
631  *	LOCKING:
632  *	spin_lock_irqsave(host lock)
633  *
634  *	RETURNS:
635  *	Number of completed commands on success, -errno otherwise.
636  */
637 int ata_qc_complete_multiple(struct ata_port *ap, u64 qc_active)
638 {
639 	u64 done_mask, ap_qc_active = ap->qc_active;
640 	int nr_done = 0;
641 
642 	/*
643 	 * If the internal tag is set on ap->qc_active, then we care about
644 	 * bit0 on the passed in qc_active mask. Move that bit up to match
645 	 * the internal tag.
646 	 */
647 	if (ap_qc_active & (1ULL << ATA_TAG_INTERNAL)) {
648 		qc_active |= (qc_active & 0x01) << ATA_TAG_INTERNAL;
649 		qc_active ^= qc_active & 0x01;
650 	}
651 
652 	done_mask = ap_qc_active ^ qc_active;
653 
654 	if (unlikely(done_mask & qc_active)) {
655 		ata_port_err(ap, "illegal qc_active transition (%08llx->%08llx)\n",
656 			     ap->qc_active, qc_active);
657 		return -EINVAL;
658 	}
659 
660 	if (ap->ops->qc_ncq_fill_rtf)
661 		ap->ops->qc_ncq_fill_rtf(ap, done_mask);
662 
663 	while (done_mask) {
664 		struct ata_queued_cmd *qc;
665 		unsigned int tag = __ffs64(done_mask);
666 
667 		qc = ata_qc_from_tag(ap, tag);
668 		if (qc) {
669 			ata_qc_complete(qc);
670 			nr_done++;
671 		}
672 		done_mask &= ~(1ULL << tag);
673 	}
674 
675 	return nr_done;
676 }
677 EXPORT_SYMBOL_GPL(ata_qc_complete_multiple);
678 
679 /**
680  *	ata_slave_link_init - initialize slave link
681  *	@ap: port to initialize slave link for
682  *
683  *	Create and initialize slave link for @ap.  This enables slave
684  *	link handling on the port.
685  *
686  *	In libata, a port contains links and a link contains devices.
687  *	There is single host link but if a PMP is attached to it,
688  *	there can be multiple fan-out links.  On SATA, there's usually
689  *	a single device connected to a link but PATA and SATA
690  *	controllers emulating TF based interface can have two - master
691  *	and slave.
692  *
693  *	However, there are a few controllers which don't fit into this
694  *	abstraction too well - SATA controllers which emulate TF
695  *	interface with both master and slave devices but also have
696  *	separate SCR register sets for each device.  These controllers
697  *	need separate links for physical link handling
698  *	(e.g. onlineness, link speed) but should be treated like a
699  *	traditional M/S controller for everything else (e.g. command
700  *	issue, softreset).
701  *
702  *	slave_link is libata's way of handling this class of
703  *	controllers without impacting core layer too much.  For
704  *	anything other than physical link handling, the default host
705  *	link is used for both master and slave.  For physical link
706  *	handling, separate @ap->slave_link is used.  All dirty details
707  *	are implemented inside libata core layer.  From LLD's POV, the
708  *	only difference is that prereset, hardreset and postreset are
709  *	called once more for the slave link, so the reset sequence
710  *	looks like the following.
711  *
712  *	prereset(M) -> prereset(S) -> hardreset(M) -> hardreset(S) ->
713  *	softreset(M) -> postreset(M) -> postreset(S)
714  *
715  *	Note that softreset is called only for the master.  Softreset
716  *	resets both M/S by definition, so SRST on master should handle
717  *	both (the standard method will work just fine).
718  *
719  *	LOCKING:
720  *	Should be called before host is registered.
721  *
722  *	RETURNS:
723  *	0 on success, -errno on failure.
724  */
725 int ata_slave_link_init(struct ata_port *ap)
726 {
727 	struct ata_link *link;
728 
729 	WARN_ON(ap->slave_link);
730 	WARN_ON(ap->flags & ATA_FLAG_PMP);
731 
732 	link = kzalloc(sizeof(*link), GFP_KERNEL);
733 	if (!link)
734 		return -ENOMEM;
735 
736 	ata_link_init(ap, link, 1);
737 	ap->slave_link = link;
738 	return 0;
739 }
740 EXPORT_SYMBOL_GPL(ata_slave_link_init);
741 
742 /**
743  *	sata_lpm_ignore_phy_events - test if PHY event should be ignored
744  *	@link: Link receiving the event
745  *
746  *	Test whether the received PHY event has to be ignored or not.
747  *
748  *	LOCKING:
749  *	None:
750  *
751  *	RETURNS:
752  *	True if the event has to be ignored.
753  */
754 bool sata_lpm_ignore_phy_events(struct ata_link *link)
755 {
756 	unsigned long lpm_timeout = link->last_lpm_change +
757 				    msecs_to_jiffies(ATA_TMOUT_SPURIOUS_PHY);
758 
759 	/* if LPM is enabled, PHYRDY doesn't mean anything */
760 	if (link->lpm_policy > ATA_LPM_MAX_POWER)
761 		return true;
762 
763 	/* ignore the first PHY event after the LPM policy changed
764 	 * as it is might be spurious
765 	 */
766 	if ((link->flags & ATA_LFLAG_CHANGED) &&
767 	    time_before(jiffies, lpm_timeout))
768 		return true;
769 
770 	return false;
771 }
772 EXPORT_SYMBOL_GPL(sata_lpm_ignore_phy_events);
773 
774 static const char *ata_lpm_policy_names[] = {
775 	[ATA_LPM_UNKNOWN]		= "max_performance",
776 	[ATA_LPM_MAX_POWER]		= "max_performance",
777 	[ATA_LPM_MED_POWER]		= "medium_power",
778 	[ATA_LPM_MED_POWER_WITH_DIPM]	= "med_power_with_dipm",
779 	[ATA_LPM_MIN_POWER_WITH_PARTIAL] = "min_power_with_partial",
780 	[ATA_LPM_MIN_POWER]		= "min_power",
781 };
782 
783 static ssize_t ata_scsi_lpm_store(struct device *device,
784 				  struct device_attribute *attr,
785 				  const char *buf, size_t count)
786 {
787 	struct Scsi_Host *shost = class_to_shost(device);
788 	struct ata_port *ap = ata_shost_to_port(shost);
789 	struct ata_link *link;
790 	struct ata_device *dev;
791 	enum ata_lpm_policy policy;
792 	unsigned long flags;
793 
794 	/* UNKNOWN is internal state, iterate from MAX_POWER */
795 	for (policy = ATA_LPM_MAX_POWER;
796 	     policy < ARRAY_SIZE(ata_lpm_policy_names); policy++) {
797 		const char *name = ata_lpm_policy_names[policy];
798 
799 		if (strncmp(name, buf, strlen(name)) == 0)
800 			break;
801 	}
802 	if (policy == ARRAY_SIZE(ata_lpm_policy_names))
803 		return -EINVAL;
804 
805 	spin_lock_irqsave(ap->lock, flags);
806 
807 	ata_for_each_link(link, ap, EDGE) {
808 		ata_for_each_dev(dev, &ap->link, ENABLED) {
809 			if (dev->horkage & ATA_HORKAGE_NOLPM) {
810 				count = -EOPNOTSUPP;
811 				goto out_unlock;
812 			}
813 		}
814 	}
815 
816 	ap->target_lpm_policy = policy;
817 	ata_port_schedule_eh(ap);
818 out_unlock:
819 	spin_unlock_irqrestore(ap->lock, flags);
820 	return count;
821 }
822 
823 static ssize_t ata_scsi_lpm_show(struct device *dev,
824 				 struct device_attribute *attr, char *buf)
825 {
826 	struct Scsi_Host *shost = class_to_shost(dev);
827 	struct ata_port *ap = ata_shost_to_port(shost);
828 
829 	if (ap->target_lpm_policy >= ARRAY_SIZE(ata_lpm_policy_names))
830 		return -EINVAL;
831 
832 	return sysfs_emit(buf, "%s\n",
833 			ata_lpm_policy_names[ap->target_lpm_policy]);
834 }
835 DEVICE_ATTR(link_power_management_policy, S_IRUGO | S_IWUSR,
836 	    ata_scsi_lpm_show, ata_scsi_lpm_store);
837 EXPORT_SYMBOL_GPL(dev_attr_link_power_management_policy);
838 
839 static ssize_t ata_ncq_prio_supported_show(struct device *device,
840 					   struct device_attribute *attr,
841 					   char *buf)
842 {
843 	struct scsi_device *sdev = to_scsi_device(device);
844 	struct ata_port *ap = ata_shost_to_port(sdev->host);
845 	struct ata_device *dev;
846 	bool ncq_prio_supported;
847 	int rc = 0;
848 
849 	spin_lock_irq(ap->lock);
850 	dev = ata_scsi_find_dev(ap, sdev);
851 	if (!dev)
852 		rc = -ENODEV;
853 	else
854 		ncq_prio_supported = dev->flags & ATA_DFLAG_NCQ_PRIO;
855 	spin_unlock_irq(ap->lock);
856 
857 	return rc ? rc : sysfs_emit(buf, "%u\n", ncq_prio_supported);
858 }
859 
860 DEVICE_ATTR(ncq_prio_supported, S_IRUGO, ata_ncq_prio_supported_show, NULL);
861 EXPORT_SYMBOL_GPL(dev_attr_ncq_prio_supported);
862 
863 static ssize_t ata_ncq_prio_enable_show(struct device *device,
864 					struct device_attribute *attr,
865 					char *buf)
866 {
867 	struct scsi_device *sdev = to_scsi_device(device);
868 	struct ata_port *ap = ata_shost_to_port(sdev->host);
869 	struct ata_device *dev;
870 	bool ncq_prio_enable;
871 	int rc = 0;
872 
873 	spin_lock_irq(ap->lock);
874 	dev = ata_scsi_find_dev(ap, sdev);
875 	if (!dev)
876 		rc = -ENODEV;
877 	else
878 		ncq_prio_enable = dev->flags & ATA_DFLAG_NCQ_PRIO_ENABLED;
879 	spin_unlock_irq(ap->lock);
880 
881 	return rc ? rc : sysfs_emit(buf, "%u\n", ncq_prio_enable);
882 }
883 
884 static ssize_t ata_ncq_prio_enable_store(struct device *device,
885 					 struct device_attribute *attr,
886 					 const char *buf, size_t len)
887 {
888 	struct scsi_device *sdev = to_scsi_device(device);
889 	struct ata_port *ap;
890 	struct ata_device *dev;
891 	long int input;
892 	int rc = 0;
893 
894 	rc = kstrtol(buf, 10, &input);
895 	if (rc)
896 		return rc;
897 	if ((input < 0) || (input > 1))
898 		return -EINVAL;
899 
900 	ap = ata_shost_to_port(sdev->host);
901 	dev = ata_scsi_find_dev(ap, sdev);
902 	if (unlikely(!dev))
903 		return  -ENODEV;
904 
905 	spin_lock_irq(ap->lock);
906 
907 	if (!(dev->flags & ATA_DFLAG_NCQ_PRIO)) {
908 		rc = -EINVAL;
909 		goto unlock;
910 	}
911 
912 	if (input) {
913 		if (dev->flags & ATA_DFLAG_CDL_ENABLED) {
914 			ata_dev_err(dev,
915 				"CDL must be disabled to enable NCQ priority\n");
916 			rc = -EINVAL;
917 			goto unlock;
918 		}
919 		dev->flags |= ATA_DFLAG_NCQ_PRIO_ENABLED;
920 	} else {
921 		dev->flags &= ~ATA_DFLAG_NCQ_PRIO_ENABLED;
922 	}
923 
924 unlock:
925 	spin_unlock_irq(ap->lock);
926 
927 	return rc ? rc : len;
928 }
929 
930 DEVICE_ATTR(ncq_prio_enable, S_IRUGO | S_IWUSR,
931 	    ata_ncq_prio_enable_show, ata_ncq_prio_enable_store);
932 EXPORT_SYMBOL_GPL(dev_attr_ncq_prio_enable);
933 
934 static struct attribute *ata_ncq_sdev_attrs[] = {
935 	&dev_attr_unload_heads.attr,
936 	&dev_attr_ncq_prio_enable.attr,
937 	&dev_attr_ncq_prio_supported.attr,
938 	NULL
939 };
940 
941 static const struct attribute_group ata_ncq_sdev_attr_group = {
942 	.attrs = ata_ncq_sdev_attrs
943 };
944 
945 const struct attribute_group *ata_ncq_sdev_groups[] = {
946 	&ata_ncq_sdev_attr_group,
947 	NULL
948 };
949 EXPORT_SYMBOL_GPL(ata_ncq_sdev_groups);
950 
951 static ssize_t
952 ata_scsi_em_message_store(struct device *dev, struct device_attribute *attr,
953 			  const char *buf, size_t count)
954 {
955 	struct Scsi_Host *shost = class_to_shost(dev);
956 	struct ata_port *ap = ata_shost_to_port(shost);
957 	if (ap->ops->em_store && (ap->flags & ATA_FLAG_EM))
958 		return ap->ops->em_store(ap, buf, count);
959 	return -EINVAL;
960 }
961 
962 static ssize_t
963 ata_scsi_em_message_show(struct device *dev, struct device_attribute *attr,
964 			 char *buf)
965 {
966 	struct Scsi_Host *shost = class_to_shost(dev);
967 	struct ata_port *ap = ata_shost_to_port(shost);
968 
969 	if (ap->ops->em_show && (ap->flags & ATA_FLAG_EM))
970 		return ap->ops->em_show(ap, buf);
971 	return -EINVAL;
972 }
973 DEVICE_ATTR(em_message, S_IRUGO | S_IWUSR,
974 		ata_scsi_em_message_show, ata_scsi_em_message_store);
975 EXPORT_SYMBOL_GPL(dev_attr_em_message);
976 
977 static ssize_t
978 ata_scsi_em_message_type_show(struct device *dev, struct device_attribute *attr,
979 			      char *buf)
980 {
981 	struct Scsi_Host *shost = class_to_shost(dev);
982 	struct ata_port *ap = ata_shost_to_port(shost);
983 
984 	return sysfs_emit(buf, "%d\n", ap->em_message_type);
985 }
986 DEVICE_ATTR(em_message_type, S_IRUGO,
987 		  ata_scsi_em_message_type_show, NULL);
988 EXPORT_SYMBOL_GPL(dev_attr_em_message_type);
989 
990 static ssize_t
991 ata_scsi_activity_show(struct device *dev, struct device_attribute *attr,
992 		char *buf)
993 {
994 	struct scsi_device *sdev = to_scsi_device(dev);
995 	struct ata_port *ap = ata_shost_to_port(sdev->host);
996 	struct ata_device *atadev = ata_scsi_find_dev(ap, sdev);
997 
998 	if (atadev && ap->ops->sw_activity_show &&
999 	    (ap->flags & ATA_FLAG_SW_ACTIVITY))
1000 		return ap->ops->sw_activity_show(atadev, buf);
1001 	return -EINVAL;
1002 }
1003 
1004 static ssize_t
1005 ata_scsi_activity_store(struct device *dev, struct device_attribute *attr,
1006 	const char *buf, size_t count)
1007 {
1008 	struct scsi_device *sdev = to_scsi_device(dev);
1009 	struct ata_port *ap = ata_shost_to_port(sdev->host);
1010 	struct ata_device *atadev = ata_scsi_find_dev(ap, sdev);
1011 	enum sw_activity val;
1012 	int rc;
1013 
1014 	if (atadev && ap->ops->sw_activity_store &&
1015 	    (ap->flags & ATA_FLAG_SW_ACTIVITY)) {
1016 		val = simple_strtoul(buf, NULL, 0);
1017 		switch (val) {
1018 		case OFF: case BLINK_ON: case BLINK_OFF:
1019 			rc = ap->ops->sw_activity_store(atadev, val);
1020 			if (!rc)
1021 				return count;
1022 			else
1023 				return rc;
1024 		}
1025 	}
1026 	return -EINVAL;
1027 }
1028 DEVICE_ATTR(sw_activity, S_IWUSR | S_IRUGO, ata_scsi_activity_show,
1029 			ata_scsi_activity_store);
1030 EXPORT_SYMBOL_GPL(dev_attr_sw_activity);
1031 
1032 /**
1033  *	ata_change_queue_depth - Set a device maximum queue depth
1034  *	@ap: ATA port of the target device
1035  *	@dev: target ATA device
1036  *	@sdev: SCSI device to configure queue depth for
1037  *	@queue_depth: new queue depth
1038  *
1039  *	Helper to set a device maximum queue depth, usable with both libsas
1040  *	and libata.
1041  *
1042  */
1043 int ata_change_queue_depth(struct ata_port *ap, struct ata_device *dev,
1044 			   struct scsi_device *sdev, int queue_depth)
1045 {
1046 	unsigned long flags;
1047 
1048 	if (!dev || !ata_dev_enabled(dev))
1049 		return sdev->queue_depth;
1050 
1051 	if (queue_depth < 1 || queue_depth == sdev->queue_depth)
1052 		return sdev->queue_depth;
1053 
1054 	/* NCQ enabled? */
1055 	spin_lock_irqsave(ap->lock, flags);
1056 	dev->flags &= ~ATA_DFLAG_NCQ_OFF;
1057 	if (queue_depth == 1 || !ata_ncq_enabled(dev)) {
1058 		dev->flags |= ATA_DFLAG_NCQ_OFF;
1059 		queue_depth = 1;
1060 	}
1061 	spin_unlock_irqrestore(ap->lock, flags);
1062 
1063 	/* limit and apply queue depth */
1064 	queue_depth = min(queue_depth, sdev->host->can_queue);
1065 	queue_depth = min(queue_depth, ata_id_queue_depth(dev->id));
1066 	queue_depth = min(queue_depth, ATA_MAX_QUEUE);
1067 
1068 	if (sdev->queue_depth == queue_depth)
1069 		return -EINVAL;
1070 
1071 	return scsi_change_queue_depth(sdev, queue_depth);
1072 }
1073 EXPORT_SYMBOL_GPL(ata_change_queue_depth);
1074 
1075 /**
1076  *	ata_scsi_change_queue_depth - SCSI callback for queue depth config
1077  *	@sdev: SCSI device to configure queue depth for
1078  *	@queue_depth: new queue depth
1079  *
1080  *	This is libata standard hostt->change_queue_depth callback.
1081  *	SCSI will call into this callback when user tries to set queue
1082  *	depth via sysfs.
1083  *
1084  *	LOCKING:
1085  *	SCSI layer (we don't care)
1086  *
1087  *	RETURNS:
1088  *	Newly configured queue depth.
1089  */
1090 int ata_scsi_change_queue_depth(struct scsi_device *sdev, int queue_depth)
1091 {
1092 	struct ata_port *ap = ata_shost_to_port(sdev->host);
1093 
1094 	return ata_change_queue_depth(ap, ata_scsi_find_dev(ap, sdev),
1095 				      sdev, queue_depth);
1096 }
1097 EXPORT_SYMBOL_GPL(ata_scsi_change_queue_depth);
1098 
1099 /**
1100  *	ata_sas_port_alloc - Allocate port for a SAS attached SATA device
1101  *	@host: ATA host container for all SAS ports
1102  *	@port_info: Information from low-level host driver
1103  *	@shost: SCSI host that the scsi device is attached to
1104  *
1105  *	LOCKING:
1106  *	PCI/etc. bus probe sem.
1107  *
1108  *	RETURNS:
1109  *	ata_port pointer on success / NULL on failure.
1110  */
1111 
1112 struct ata_port *ata_sas_port_alloc(struct ata_host *host,
1113 				    struct ata_port_info *port_info,
1114 				    struct Scsi_Host *shost)
1115 {
1116 	struct ata_port *ap;
1117 
1118 	ap = ata_port_alloc(host);
1119 	if (!ap)
1120 		return NULL;
1121 
1122 	ap->port_no = 0;
1123 	ap->lock = &host->lock;
1124 	ap->pio_mask = port_info->pio_mask;
1125 	ap->mwdma_mask = port_info->mwdma_mask;
1126 	ap->udma_mask = port_info->udma_mask;
1127 	ap->flags |= port_info->flags;
1128 	ap->ops = port_info->port_ops;
1129 	ap->cbl = ATA_CBL_SATA;
1130 
1131 	return ap;
1132 }
1133 EXPORT_SYMBOL_GPL(ata_sas_port_alloc);
1134 
1135 /**
1136  *	ata_sas_port_start - Set port up for dma.
1137  *	@ap: Port to initialize
1138  *
1139  *	Called just after data structures for each port are
1140  *	initialized.
1141  *
1142  *	May be used as the port_start() entry in ata_port_operations.
1143  *
1144  *	LOCKING:
1145  *	Inherited from caller.
1146  */
1147 int ata_sas_port_start(struct ata_port *ap)
1148 {
1149 	/*
1150 	 * the port is marked as frozen at allocation time, but if we don't
1151 	 * have new eh, we won't thaw it
1152 	 */
1153 	if (!ap->ops->error_handler)
1154 		ap->pflags &= ~ATA_PFLAG_FROZEN;
1155 	return 0;
1156 }
1157 EXPORT_SYMBOL_GPL(ata_sas_port_start);
1158 
1159 /**
1160  *	ata_sas_port_stop - Undo ata_sas_port_start()
1161  *	@ap: Port to shut down
1162  *
1163  *	May be used as the port_stop() entry in ata_port_operations.
1164  *
1165  *	LOCKING:
1166  *	Inherited from caller.
1167  */
1168 
1169 void ata_sas_port_stop(struct ata_port *ap)
1170 {
1171 }
1172 EXPORT_SYMBOL_GPL(ata_sas_port_stop);
1173 
1174 /**
1175  * ata_sas_async_probe - simply schedule probing and return
1176  * @ap: Port to probe
1177  *
1178  * For batch scheduling of probe for sas attached ata devices, assumes
1179  * the port has already been through ata_sas_port_init()
1180  */
1181 void ata_sas_async_probe(struct ata_port *ap)
1182 {
1183 	__ata_port_probe(ap);
1184 }
1185 EXPORT_SYMBOL_GPL(ata_sas_async_probe);
1186 
1187 int ata_sas_sync_probe(struct ata_port *ap)
1188 {
1189 	return ata_port_probe(ap);
1190 }
1191 EXPORT_SYMBOL_GPL(ata_sas_sync_probe);
1192 
1193 
1194 /**
1195  *	ata_sas_port_init - Initialize a SATA device
1196  *	@ap: SATA port to initialize
1197  *
1198  *	LOCKING:
1199  *	PCI/etc. bus probe sem.
1200  *
1201  *	RETURNS:
1202  *	Zero on success, non-zero on error.
1203  */
1204 
1205 int ata_sas_port_init(struct ata_port *ap)
1206 {
1207 	int rc = ap->ops->port_start(ap);
1208 
1209 	if (rc)
1210 		return rc;
1211 	ap->print_id = atomic_inc_return(&ata_print_id);
1212 	return 0;
1213 }
1214 EXPORT_SYMBOL_GPL(ata_sas_port_init);
1215 
1216 int ata_sas_tport_add(struct device *parent, struct ata_port *ap)
1217 {
1218 	return ata_tport_add(parent, ap);
1219 }
1220 EXPORT_SYMBOL_GPL(ata_sas_tport_add);
1221 
1222 void ata_sas_tport_delete(struct ata_port *ap)
1223 {
1224 	ata_tport_delete(ap);
1225 }
1226 EXPORT_SYMBOL_GPL(ata_sas_tport_delete);
1227 
1228 /**
1229  *	ata_sas_port_destroy - Destroy a SATA port allocated by ata_sas_port_alloc
1230  *	@ap: SATA port to destroy
1231  *
1232  */
1233 
1234 void ata_sas_port_destroy(struct ata_port *ap)
1235 {
1236 	if (ap->ops->port_stop)
1237 		ap->ops->port_stop(ap);
1238 	kfree(ap);
1239 }
1240 EXPORT_SYMBOL_GPL(ata_sas_port_destroy);
1241 
1242 /**
1243  *	ata_sas_slave_configure - Default slave_config routine for libata devices
1244  *	@sdev: SCSI device to configure
1245  *	@ap: ATA port to which SCSI device is attached
1246  *
1247  *	RETURNS:
1248  *	Zero.
1249  */
1250 
1251 int ata_sas_slave_configure(struct scsi_device *sdev, struct ata_port *ap)
1252 {
1253 	ata_scsi_sdev_config(sdev);
1254 	ata_scsi_dev_config(sdev, ap->link.device);
1255 	return 0;
1256 }
1257 EXPORT_SYMBOL_GPL(ata_sas_slave_configure);
1258 
1259 /**
1260  *	ata_sas_queuecmd - Issue SCSI cdb to libata-managed device
1261  *	@cmd: SCSI command to be sent
1262  *	@ap:	ATA port to which the command is being sent
1263  *
1264  *	RETURNS:
1265  *	Return value from __ata_scsi_queuecmd() if @cmd can be queued,
1266  *	0 otherwise.
1267  */
1268 
1269 int ata_sas_queuecmd(struct scsi_cmnd *cmd, struct ata_port *ap)
1270 {
1271 	int rc = 0;
1272 
1273 	if (likely(ata_dev_enabled(ap->link.device)))
1274 		rc = __ata_scsi_queuecmd(cmd, ap->link.device);
1275 	else {
1276 		cmd->result = (DID_BAD_TARGET << 16);
1277 		scsi_done(cmd);
1278 	}
1279 	return rc;
1280 }
1281 EXPORT_SYMBOL_GPL(ata_sas_queuecmd);
1282 
1283 /**
1284  *	sata_async_notification - SATA async notification handler
1285  *	@ap: ATA port where async notification is received
1286  *
1287  *	Handler to be called when async notification via SDB FIS is
1288  *	received.  This function schedules EH if necessary.
1289  *
1290  *	LOCKING:
1291  *	spin_lock_irqsave(host lock)
1292  *
1293  *	RETURNS:
1294  *	1 if EH is scheduled, 0 otherwise.
1295  */
1296 int sata_async_notification(struct ata_port *ap)
1297 {
1298 	u32 sntf;
1299 	int rc;
1300 
1301 	if (!(ap->flags & ATA_FLAG_AN))
1302 		return 0;
1303 
1304 	rc = sata_scr_read(&ap->link, SCR_NOTIFICATION, &sntf);
1305 	if (rc == 0)
1306 		sata_scr_write(&ap->link, SCR_NOTIFICATION, sntf);
1307 
1308 	if (!sata_pmp_attached(ap) || rc) {
1309 		/* PMP is not attached or SNTF is not available */
1310 		if (!sata_pmp_attached(ap)) {
1311 			/* PMP is not attached.  Check whether ATAPI
1312 			 * AN is configured.  If so, notify media
1313 			 * change.
1314 			 */
1315 			struct ata_device *dev = ap->link.device;
1316 
1317 			if ((dev->class == ATA_DEV_ATAPI) &&
1318 			    (dev->flags & ATA_DFLAG_AN))
1319 				ata_scsi_media_change_notify(dev);
1320 			return 0;
1321 		} else {
1322 			/* PMP is attached but SNTF is not available.
1323 			 * ATAPI async media change notification is
1324 			 * not used.  The PMP must be reporting PHY
1325 			 * status change, schedule EH.
1326 			 */
1327 			ata_port_schedule_eh(ap);
1328 			return 1;
1329 		}
1330 	} else {
1331 		/* PMP is attached and SNTF is available */
1332 		struct ata_link *link;
1333 
1334 		/* check and notify ATAPI AN */
1335 		ata_for_each_link(link, ap, EDGE) {
1336 			if (!(sntf & (1 << link->pmp)))
1337 				continue;
1338 
1339 			if ((link->device->class == ATA_DEV_ATAPI) &&
1340 			    (link->device->flags & ATA_DFLAG_AN))
1341 				ata_scsi_media_change_notify(link->device);
1342 		}
1343 
1344 		/* If PMP is reporting that PHY status of some
1345 		 * downstream ports has changed, schedule EH.
1346 		 */
1347 		if (sntf & (1 << SATA_PMP_CTRL_PORT)) {
1348 			ata_port_schedule_eh(ap);
1349 			return 1;
1350 		}
1351 
1352 		return 0;
1353 	}
1354 }
1355 EXPORT_SYMBOL_GPL(sata_async_notification);
1356 
1357 /**
1358  *	ata_eh_read_log_10h - Read log page 10h for NCQ error details
1359  *	@dev: Device to read log page 10h from
1360  *	@tag: Resulting tag of the failed command
1361  *	@tf: Resulting taskfile registers of the failed command
1362  *
1363  *	Read log page 10h to obtain NCQ error details and clear error
1364  *	condition.
1365  *
1366  *	LOCKING:
1367  *	Kernel thread context (may sleep).
1368  *
1369  *	RETURNS:
1370  *	0 on success, -errno otherwise.
1371  */
1372 static int ata_eh_read_log_10h(struct ata_device *dev,
1373 			       int *tag, struct ata_taskfile *tf)
1374 {
1375 	u8 *buf = dev->link->ap->sector_buf;
1376 	unsigned int err_mask;
1377 	u8 csum;
1378 	int i;
1379 
1380 	err_mask = ata_read_log_page(dev, ATA_LOG_SATA_NCQ, 0, buf, 1);
1381 	if (err_mask)
1382 		return -EIO;
1383 
1384 	csum = 0;
1385 	for (i = 0; i < ATA_SECT_SIZE; i++)
1386 		csum += buf[i];
1387 	if (csum)
1388 		ata_dev_warn(dev, "invalid checksum 0x%x on log page 10h\n",
1389 			     csum);
1390 
1391 	if (buf[0] & 0x80)
1392 		return -ENOENT;
1393 
1394 	*tag = buf[0] & 0x1f;
1395 
1396 	tf->status = buf[2];
1397 	tf->error = buf[3];
1398 	tf->lbal = buf[4];
1399 	tf->lbam = buf[5];
1400 	tf->lbah = buf[6];
1401 	tf->device = buf[7];
1402 	tf->hob_lbal = buf[8];
1403 	tf->hob_lbam = buf[9];
1404 	tf->hob_lbah = buf[10];
1405 	tf->nsect = buf[12];
1406 	tf->hob_nsect = buf[13];
1407 	if (ata_id_has_ncq_autosense(dev->id) && (tf->status & ATA_SENSE))
1408 		tf->auxiliary = buf[14] << 16 | buf[15] << 8 | buf[16];
1409 
1410 	return 0;
1411 }
1412 
1413 /**
1414  *	ata_eh_read_sense_success_ncq_log - Read the sense data for successful
1415  *					    NCQ commands log
1416  *	@link: ATA link to get sense data for
1417  *
1418  *	Read the sense data for successful NCQ commands log page to obtain
1419  *	sense data for all NCQ commands that completed successfully with
1420  *	the sense data available bit set.
1421  *
1422  *	LOCKING:
1423  *	Kernel thread context (may sleep).
1424  *
1425  *	RETURNS:
1426  *	0 on success, -errno otherwise.
1427  */
1428 int ata_eh_read_sense_success_ncq_log(struct ata_link *link)
1429 {
1430 	struct ata_device *dev = link->device;
1431 	struct ata_port *ap = dev->link->ap;
1432 	u8 *buf = ap->ncq_sense_buf;
1433 	struct ata_queued_cmd *qc;
1434 	unsigned int err_mask, tag;
1435 	u8 *sense, sk = 0, asc = 0, ascq = 0;
1436 	u64 sense_valid, val;
1437 	int ret = 0;
1438 
1439 	err_mask = ata_read_log_page(dev, ATA_LOG_SENSE_NCQ, 0, buf, 2);
1440 	if (err_mask) {
1441 		ata_dev_err(dev,
1442 			"Failed to read Sense Data for Successful NCQ Commands log\n");
1443 		return -EIO;
1444 	}
1445 
1446 	/* Check the log header */
1447 	val = get_unaligned_le64(&buf[0]);
1448 	if ((val & 0xffff) != 1 || ((val >> 16) & 0xff) != 0x0f) {
1449 		ata_dev_err(dev,
1450 			"Invalid Sense Data for Successful NCQ Commands log\n");
1451 		return -EIO;
1452 	}
1453 
1454 	sense_valid = (u64)buf[8] | ((u64)buf[9] << 8) |
1455 		((u64)buf[10] << 16) | ((u64)buf[11] << 24);
1456 
1457 	ata_qc_for_each_raw(ap, qc, tag) {
1458 		if (!(qc->flags & ATA_QCFLAG_EH) ||
1459 		    !(qc->flags & ATA_QCFLAG_EH_SUCCESS_CMD) ||
1460 		    qc->err_mask ||
1461 		    ata_dev_phys_link(qc->dev) != link)
1462 			continue;
1463 
1464 		/*
1465 		 * If the command does not have any sense data, clear ATA_SENSE.
1466 		 * Keep ATA_QCFLAG_EH_SUCCESS_CMD so that command is finished.
1467 		 */
1468 		if (!(sense_valid & (1ULL << tag))) {
1469 			qc->result_tf.status &= ~ATA_SENSE;
1470 			continue;
1471 		}
1472 
1473 		sense = &buf[32 + 24 * tag];
1474 		sk = sense[0];
1475 		asc = sense[1];
1476 		ascq = sense[2];
1477 
1478 		if (!ata_scsi_sense_is_valid(sk, asc, ascq)) {
1479 			ret = -EIO;
1480 			continue;
1481 		}
1482 
1483 		/* Set sense without also setting scsicmd->result */
1484 		scsi_build_sense_buffer(dev->flags & ATA_DFLAG_D_SENSE,
1485 					qc->scsicmd->sense_buffer, sk,
1486 					asc, ascq);
1487 		qc->flags |= ATA_QCFLAG_SENSE_VALID;
1488 
1489 		/*
1490 		 * If we have sense data, call scsi_check_sense() in order to
1491 		 * set the correct SCSI ML byte (if any). No point in checking
1492 		 * the return value, since the command has already completed
1493 		 * successfully.
1494 		 */
1495 		scsi_check_sense(qc->scsicmd);
1496 	}
1497 
1498 	return ret;
1499 }
1500 EXPORT_SYMBOL_GPL(ata_eh_read_sense_success_ncq_log);
1501 
1502 /**
1503  *	ata_eh_analyze_ncq_error - analyze NCQ error
1504  *	@link: ATA link to analyze NCQ error for
1505  *
1506  *	Read log page 10h, determine the offending qc and acquire
1507  *	error status TF.  For NCQ device errors, all LLDDs have to do
1508  *	is setting AC_ERR_DEV in ehi->err_mask.  This function takes
1509  *	care of the rest.
1510  *
1511  *	LOCKING:
1512  *	Kernel thread context (may sleep).
1513  */
1514 void ata_eh_analyze_ncq_error(struct ata_link *link)
1515 {
1516 	struct ata_port *ap = link->ap;
1517 	struct ata_eh_context *ehc = &link->eh_context;
1518 	struct ata_device *dev = link->device;
1519 	struct ata_queued_cmd *qc;
1520 	struct ata_taskfile tf;
1521 	int tag, rc;
1522 
1523 	/* if frozen, we can't do much */
1524 	if (ata_port_is_frozen(ap))
1525 		return;
1526 
1527 	/* is it NCQ device error? */
1528 	if (!link->sactive || !(ehc->i.err_mask & AC_ERR_DEV))
1529 		return;
1530 
1531 	/* has LLDD analyzed already? */
1532 	ata_qc_for_each_raw(ap, qc, tag) {
1533 		if (!(qc->flags & ATA_QCFLAG_EH))
1534 			continue;
1535 
1536 		if (qc->err_mask)
1537 			return;
1538 	}
1539 
1540 	/* okay, this error is ours */
1541 	memset(&tf, 0, sizeof(tf));
1542 	rc = ata_eh_read_log_10h(dev, &tag, &tf);
1543 	if (rc) {
1544 		ata_link_err(link, "failed to read log page 10h (errno=%d)\n",
1545 			     rc);
1546 		return;
1547 	}
1548 
1549 	if (!(link->sactive & (1 << tag))) {
1550 		ata_link_err(link, "log page 10h reported inactive tag %d\n",
1551 			     tag);
1552 		return;
1553 	}
1554 
1555 	/* we've got the perpetrator, condemn it */
1556 	qc = __ata_qc_from_tag(ap, tag);
1557 	memcpy(&qc->result_tf, &tf, sizeof(tf));
1558 	qc->result_tf.flags = ATA_TFLAG_ISADDR | ATA_TFLAG_LBA | ATA_TFLAG_LBA48;
1559 	qc->err_mask |= AC_ERR_DEV | AC_ERR_NCQ;
1560 
1561 	/*
1562 	 * If the device supports NCQ autosense, ata_eh_read_log_10h() will have
1563 	 * stored the sense data in qc->result_tf.auxiliary.
1564 	 */
1565 	if (qc->result_tf.auxiliary) {
1566 		char sense_key, asc, ascq;
1567 
1568 		sense_key = (qc->result_tf.auxiliary >> 16) & 0xff;
1569 		asc = (qc->result_tf.auxiliary >> 8) & 0xff;
1570 		ascq = qc->result_tf.auxiliary & 0xff;
1571 		if (ata_scsi_sense_is_valid(sense_key, asc, ascq)) {
1572 			ata_scsi_set_sense(dev, qc->scsicmd, sense_key, asc,
1573 					   ascq);
1574 			ata_scsi_set_sense_information(dev, qc->scsicmd,
1575 						       &qc->result_tf);
1576 			qc->flags |= ATA_QCFLAG_SENSE_VALID;
1577 		}
1578 	}
1579 
1580 	ata_qc_for_each_raw(ap, qc, tag) {
1581 		if (!(qc->flags & ATA_QCFLAG_EH) ||
1582 		    qc->flags & ATA_QCFLAG_EH_SUCCESS_CMD ||
1583 		    ata_dev_phys_link(qc->dev) != link)
1584 			continue;
1585 
1586 		/* Skip the single QC which caused the NCQ error. */
1587 		if (qc->err_mask)
1588 			continue;
1589 
1590 		/*
1591 		 * For SATA, the STATUS and ERROR fields are shared for all NCQ
1592 		 * commands that were completed with the same SDB FIS.
1593 		 * Therefore, we have to clear the ATA_ERR bit for all QCs
1594 		 * except the one that caused the NCQ error.
1595 		 */
1596 		qc->result_tf.status &= ~ATA_ERR;
1597 		qc->result_tf.error = 0;
1598 
1599 		/*
1600 		 * If we get a NCQ error, that means that a single command was
1601 		 * aborted. All other failed commands for our link should be
1602 		 * retried and has no business of going though further scrutiny
1603 		 * by ata_eh_link_autopsy().
1604 		 */
1605 		qc->flags |= ATA_QCFLAG_RETRY;
1606 	}
1607 
1608 	ehc->i.err_mask &= ~AC_ERR_DEV;
1609 }
1610 EXPORT_SYMBOL_GPL(ata_eh_analyze_ncq_error);
1611