xref: /openbmc/linux/drivers/ata/libata-sata.c (revision 046b212a)
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 int sata_deb_timing_normal[]		= {   5,  100, 2000 };
23 EXPORT_SYMBOL_GPL(sata_deb_timing_normal);
24 const unsigned int sata_deb_timing_hotplug[]		= {  25,  500, 2000 };
25 EXPORT_SYMBOL_GPL(sata_deb_timing_hotplug);
26 const unsigned int 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 int *params,
236 		       unsigned long deadline)
237 {
238 	unsigned int interval = params[0];
239 	unsigned int 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 int *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 int *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  *	@sdev: SCSI device to configure queue depth for
1036  *	@queue_depth: new queue depth
1037  *
1038  *	Helper to set a device maximum queue depth, usable with both libsas
1039  *	and libata.
1040  *
1041  */
1042 int ata_change_queue_depth(struct ata_port *ap, struct scsi_device *sdev,
1043 			   int queue_depth)
1044 {
1045 	struct ata_device *dev;
1046 	unsigned long flags;
1047 	int max_queue_depth;
1048 
1049 	spin_lock_irqsave(ap->lock, flags);
1050 
1051 	dev = ata_scsi_find_dev(ap, sdev);
1052 	if (!dev || queue_depth < 1 || queue_depth == sdev->queue_depth) {
1053 		spin_unlock_irqrestore(ap->lock, flags);
1054 		return sdev->queue_depth;
1055 	}
1056 
1057 	/*
1058 	 * Make sure that the queue depth requested does not exceed the device
1059 	 * capabilities.
1060 	 */
1061 	max_queue_depth = min(ATA_MAX_QUEUE, sdev->host->can_queue);
1062 	max_queue_depth = min(max_queue_depth, ata_id_queue_depth(dev->id));
1063 	if (queue_depth > max_queue_depth) {
1064 		spin_unlock_irqrestore(ap->lock, flags);
1065 		return -EINVAL;
1066 	}
1067 
1068 	/*
1069 	 * If NCQ is not supported by the device or if the target queue depth
1070 	 * is 1 (to disable drive side command queueing), turn off NCQ.
1071 	 */
1072 	if (queue_depth == 1 || !ata_ncq_supported(dev)) {
1073 		dev->flags |= ATA_DFLAG_NCQ_OFF;
1074 		queue_depth = 1;
1075 	} else {
1076 		dev->flags &= ~ATA_DFLAG_NCQ_OFF;
1077 	}
1078 
1079 	spin_unlock_irqrestore(ap->lock, flags);
1080 
1081 	if (queue_depth == sdev->queue_depth)
1082 		return sdev->queue_depth;
1083 
1084 	return scsi_change_queue_depth(sdev, queue_depth);
1085 }
1086 EXPORT_SYMBOL_GPL(ata_change_queue_depth);
1087 
1088 /**
1089  *	ata_scsi_change_queue_depth - SCSI callback for queue depth config
1090  *	@sdev: SCSI device to configure queue depth for
1091  *	@queue_depth: new queue depth
1092  *
1093  *	This is libata standard hostt->change_queue_depth callback.
1094  *	SCSI will call into this callback when user tries to set queue
1095  *	depth via sysfs.
1096  *
1097  *	LOCKING:
1098  *	SCSI layer (we don't care)
1099  *
1100  *	RETURNS:
1101  *	Newly configured queue depth.
1102  */
1103 int ata_scsi_change_queue_depth(struct scsi_device *sdev, int queue_depth)
1104 {
1105 	struct ata_port *ap = ata_shost_to_port(sdev->host);
1106 
1107 	return ata_change_queue_depth(ap, sdev, queue_depth);
1108 }
1109 EXPORT_SYMBOL_GPL(ata_scsi_change_queue_depth);
1110 
1111 /**
1112  *	ata_sas_port_alloc - Allocate port for a SAS attached SATA device
1113  *	@host: ATA host container for all SAS ports
1114  *	@port_info: Information from low-level host driver
1115  *	@shost: SCSI host that the scsi device is attached to
1116  *
1117  *	LOCKING:
1118  *	PCI/etc. bus probe sem.
1119  *
1120  *	RETURNS:
1121  *	ata_port pointer on success / NULL on failure.
1122  */
1123 
1124 struct ata_port *ata_sas_port_alloc(struct ata_host *host,
1125 				    struct ata_port_info *port_info,
1126 				    struct Scsi_Host *shost)
1127 {
1128 	struct ata_port *ap;
1129 
1130 	ap = ata_port_alloc(host);
1131 	if (!ap)
1132 		return NULL;
1133 
1134 	ap->port_no = 0;
1135 	ap->lock = &host->lock;
1136 	ap->pio_mask = port_info->pio_mask;
1137 	ap->mwdma_mask = port_info->mwdma_mask;
1138 	ap->udma_mask = port_info->udma_mask;
1139 	ap->flags |= port_info->flags;
1140 	ap->ops = port_info->port_ops;
1141 	ap->cbl = ATA_CBL_SATA;
1142 	ap->print_id = atomic_inc_return(&ata_print_id);
1143 
1144 	return ap;
1145 }
1146 EXPORT_SYMBOL_GPL(ata_sas_port_alloc);
1147 
1148 int ata_sas_tport_add(struct device *parent, struct ata_port *ap)
1149 {
1150 	return ata_tport_add(parent, ap);
1151 }
1152 EXPORT_SYMBOL_GPL(ata_sas_tport_add);
1153 
1154 void ata_sas_tport_delete(struct ata_port *ap)
1155 {
1156 	ata_tport_delete(ap);
1157 }
1158 EXPORT_SYMBOL_GPL(ata_sas_tport_delete);
1159 
1160 /**
1161  *	ata_sas_slave_configure - Default slave_config routine for libata devices
1162  *	@sdev: SCSI device to configure
1163  *	@ap: ATA port to which SCSI device is attached
1164  *
1165  *	RETURNS:
1166  *	Zero.
1167  */
1168 
1169 int ata_sas_slave_configure(struct scsi_device *sdev, struct ata_port *ap)
1170 {
1171 	ata_scsi_sdev_config(sdev);
1172 	ata_scsi_dev_config(sdev, ap->link.device);
1173 	return 0;
1174 }
1175 EXPORT_SYMBOL_GPL(ata_sas_slave_configure);
1176 
1177 /**
1178  *	ata_sas_queuecmd - Issue SCSI cdb to libata-managed device
1179  *	@cmd: SCSI command to be sent
1180  *	@ap:	ATA port to which the command is being sent
1181  *
1182  *	RETURNS:
1183  *	Return value from __ata_scsi_queuecmd() if @cmd can be queued,
1184  *	0 otherwise.
1185  */
1186 
1187 int ata_sas_queuecmd(struct scsi_cmnd *cmd, struct ata_port *ap)
1188 {
1189 	int rc = 0;
1190 
1191 	if (likely(ata_dev_enabled(ap->link.device)))
1192 		rc = __ata_scsi_queuecmd(cmd, ap->link.device);
1193 	else {
1194 		cmd->result = (DID_BAD_TARGET << 16);
1195 		scsi_done(cmd);
1196 	}
1197 	return rc;
1198 }
1199 EXPORT_SYMBOL_GPL(ata_sas_queuecmd);
1200 
1201 /**
1202  *	sata_async_notification - SATA async notification handler
1203  *	@ap: ATA port where async notification is received
1204  *
1205  *	Handler to be called when async notification via SDB FIS is
1206  *	received.  This function schedules EH if necessary.
1207  *
1208  *	LOCKING:
1209  *	spin_lock_irqsave(host lock)
1210  *
1211  *	RETURNS:
1212  *	1 if EH is scheduled, 0 otherwise.
1213  */
1214 int sata_async_notification(struct ata_port *ap)
1215 {
1216 	u32 sntf;
1217 	int rc;
1218 
1219 	if (!(ap->flags & ATA_FLAG_AN))
1220 		return 0;
1221 
1222 	rc = sata_scr_read(&ap->link, SCR_NOTIFICATION, &sntf);
1223 	if (rc == 0)
1224 		sata_scr_write(&ap->link, SCR_NOTIFICATION, sntf);
1225 
1226 	if (!sata_pmp_attached(ap) || rc) {
1227 		/* PMP is not attached or SNTF is not available */
1228 		if (!sata_pmp_attached(ap)) {
1229 			/* PMP is not attached.  Check whether ATAPI
1230 			 * AN is configured.  If so, notify media
1231 			 * change.
1232 			 */
1233 			struct ata_device *dev = ap->link.device;
1234 
1235 			if ((dev->class == ATA_DEV_ATAPI) &&
1236 			    (dev->flags & ATA_DFLAG_AN))
1237 				ata_scsi_media_change_notify(dev);
1238 			return 0;
1239 		} else {
1240 			/* PMP is attached but SNTF is not available.
1241 			 * ATAPI async media change notification is
1242 			 * not used.  The PMP must be reporting PHY
1243 			 * status change, schedule EH.
1244 			 */
1245 			ata_port_schedule_eh(ap);
1246 			return 1;
1247 		}
1248 	} else {
1249 		/* PMP is attached and SNTF is available */
1250 		struct ata_link *link;
1251 
1252 		/* check and notify ATAPI AN */
1253 		ata_for_each_link(link, ap, EDGE) {
1254 			if (!(sntf & (1 << link->pmp)))
1255 				continue;
1256 
1257 			if ((link->device->class == ATA_DEV_ATAPI) &&
1258 			    (link->device->flags & ATA_DFLAG_AN))
1259 				ata_scsi_media_change_notify(link->device);
1260 		}
1261 
1262 		/* If PMP is reporting that PHY status of some
1263 		 * downstream ports has changed, schedule EH.
1264 		 */
1265 		if (sntf & (1 << SATA_PMP_CTRL_PORT)) {
1266 			ata_port_schedule_eh(ap);
1267 			return 1;
1268 		}
1269 
1270 		return 0;
1271 	}
1272 }
1273 EXPORT_SYMBOL_GPL(sata_async_notification);
1274 
1275 /**
1276  *	ata_eh_read_log_10h - Read log page 10h for NCQ error details
1277  *	@dev: Device to read log page 10h from
1278  *	@tag: Resulting tag of the failed command
1279  *	@tf: Resulting taskfile registers of the failed command
1280  *
1281  *	Read log page 10h to obtain NCQ error details and clear error
1282  *	condition.
1283  *
1284  *	LOCKING:
1285  *	Kernel thread context (may sleep).
1286  *
1287  *	RETURNS:
1288  *	0 on success, -errno otherwise.
1289  */
1290 static int ata_eh_read_log_10h(struct ata_device *dev,
1291 			       int *tag, struct ata_taskfile *tf)
1292 {
1293 	u8 *buf = dev->link->ap->sector_buf;
1294 	unsigned int err_mask;
1295 	u8 csum;
1296 	int i;
1297 
1298 	err_mask = ata_read_log_page(dev, ATA_LOG_SATA_NCQ, 0, buf, 1);
1299 	if (err_mask)
1300 		return -EIO;
1301 
1302 	csum = 0;
1303 	for (i = 0; i < ATA_SECT_SIZE; i++)
1304 		csum += buf[i];
1305 	if (csum)
1306 		ata_dev_warn(dev, "invalid checksum 0x%x on log page 10h\n",
1307 			     csum);
1308 
1309 	if (buf[0] & 0x80)
1310 		return -ENOENT;
1311 
1312 	*tag = buf[0] & 0x1f;
1313 
1314 	tf->status = buf[2];
1315 	tf->error = buf[3];
1316 	tf->lbal = buf[4];
1317 	tf->lbam = buf[5];
1318 	tf->lbah = buf[6];
1319 	tf->device = buf[7];
1320 	tf->hob_lbal = buf[8];
1321 	tf->hob_lbam = buf[9];
1322 	tf->hob_lbah = buf[10];
1323 	tf->nsect = buf[12];
1324 	tf->hob_nsect = buf[13];
1325 	if (ata_id_has_ncq_autosense(dev->id) && (tf->status & ATA_SENSE))
1326 		tf->auxiliary = buf[14] << 16 | buf[15] << 8 | buf[16];
1327 
1328 	return 0;
1329 }
1330 
1331 /**
1332  *	ata_eh_read_sense_success_ncq_log - Read the sense data for successful
1333  *					    NCQ commands log
1334  *	@link: ATA link to get sense data for
1335  *
1336  *	Read the sense data for successful NCQ commands log page to obtain
1337  *	sense data for all NCQ commands that completed successfully with
1338  *	the sense data available bit set.
1339  *
1340  *	LOCKING:
1341  *	Kernel thread context (may sleep).
1342  *
1343  *	RETURNS:
1344  *	0 on success, -errno otherwise.
1345  */
1346 int ata_eh_read_sense_success_ncq_log(struct ata_link *link)
1347 {
1348 	struct ata_device *dev = link->device;
1349 	struct ata_port *ap = dev->link->ap;
1350 	u8 *buf = ap->ncq_sense_buf;
1351 	struct ata_queued_cmd *qc;
1352 	unsigned int err_mask, tag;
1353 	u8 *sense, sk = 0, asc = 0, ascq = 0;
1354 	u64 sense_valid, val;
1355 	int ret = 0;
1356 
1357 	err_mask = ata_read_log_page(dev, ATA_LOG_SENSE_NCQ, 0, buf, 2);
1358 	if (err_mask) {
1359 		ata_dev_err(dev,
1360 			"Failed to read Sense Data for Successful NCQ Commands log\n");
1361 		return -EIO;
1362 	}
1363 
1364 	/* Check the log header */
1365 	val = get_unaligned_le64(&buf[0]);
1366 	if ((val & 0xffff) != 1 || ((val >> 16) & 0xff) != 0x0f) {
1367 		ata_dev_err(dev,
1368 			"Invalid Sense Data for Successful NCQ Commands log\n");
1369 		return -EIO;
1370 	}
1371 
1372 	sense_valid = (u64)buf[8] | ((u64)buf[9] << 8) |
1373 		((u64)buf[10] << 16) | ((u64)buf[11] << 24);
1374 
1375 	ata_qc_for_each_raw(ap, qc, tag) {
1376 		if (!(qc->flags & ATA_QCFLAG_EH) ||
1377 		    !(qc->flags & ATA_QCFLAG_EH_SUCCESS_CMD) ||
1378 		    qc->err_mask ||
1379 		    ata_dev_phys_link(qc->dev) != link)
1380 			continue;
1381 
1382 		/*
1383 		 * If the command does not have any sense data, clear ATA_SENSE.
1384 		 * Keep ATA_QCFLAG_EH_SUCCESS_CMD so that command is finished.
1385 		 */
1386 		if (!(sense_valid & (1ULL << tag))) {
1387 			qc->result_tf.status &= ~ATA_SENSE;
1388 			continue;
1389 		}
1390 
1391 		sense = &buf[32 + 24 * tag];
1392 		sk = sense[0];
1393 		asc = sense[1];
1394 		ascq = sense[2];
1395 
1396 		if (!ata_scsi_sense_is_valid(sk, asc, ascq)) {
1397 			ret = -EIO;
1398 			continue;
1399 		}
1400 
1401 		/* Set sense without also setting scsicmd->result */
1402 		scsi_build_sense_buffer(dev->flags & ATA_DFLAG_D_SENSE,
1403 					qc->scsicmd->sense_buffer, sk,
1404 					asc, ascq);
1405 		qc->flags |= ATA_QCFLAG_SENSE_VALID;
1406 
1407 		/*
1408 		 * If we have sense data, call scsi_check_sense() in order to
1409 		 * set the correct SCSI ML byte (if any). No point in checking
1410 		 * the return value, since the command has already completed
1411 		 * successfully.
1412 		 */
1413 		scsi_check_sense(qc->scsicmd);
1414 	}
1415 
1416 	return ret;
1417 }
1418 EXPORT_SYMBOL_GPL(ata_eh_read_sense_success_ncq_log);
1419 
1420 /**
1421  *	ata_eh_analyze_ncq_error - analyze NCQ error
1422  *	@link: ATA link to analyze NCQ error for
1423  *
1424  *	Read log page 10h, determine the offending qc and acquire
1425  *	error status TF.  For NCQ device errors, all LLDDs have to do
1426  *	is setting AC_ERR_DEV in ehi->err_mask.  This function takes
1427  *	care of the rest.
1428  *
1429  *	LOCKING:
1430  *	Kernel thread context (may sleep).
1431  */
1432 void ata_eh_analyze_ncq_error(struct ata_link *link)
1433 {
1434 	struct ata_port *ap = link->ap;
1435 	struct ata_eh_context *ehc = &link->eh_context;
1436 	struct ata_device *dev = link->device;
1437 	struct ata_queued_cmd *qc;
1438 	struct ata_taskfile tf;
1439 	int tag, rc;
1440 
1441 	/* if frozen, we can't do much */
1442 	if (ata_port_is_frozen(ap))
1443 		return;
1444 
1445 	/* is it NCQ device error? */
1446 	if (!link->sactive || !(ehc->i.err_mask & AC_ERR_DEV))
1447 		return;
1448 
1449 	/* has LLDD analyzed already? */
1450 	ata_qc_for_each_raw(ap, qc, tag) {
1451 		if (!(qc->flags & ATA_QCFLAG_EH))
1452 			continue;
1453 
1454 		if (qc->err_mask)
1455 			return;
1456 	}
1457 
1458 	/* okay, this error is ours */
1459 	memset(&tf, 0, sizeof(tf));
1460 	rc = ata_eh_read_log_10h(dev, &tag, &tf);
1461 	if (rc) {
1462 		ata_link_err(link, "failed to read log page 10h (errno=%d)\n",
1463 			     rc);
1464 		return;
1465 	}
1466 
1467 	if (!(link->sactive & (1 << tag))) {
1468 		ata_link_err(link, "log page 10h reported inactive tag %d\n",
1469 			     tag);
1470 		return;
1471 	}
1472 
1473 	/* we've got the perpetrator, condemn it */
1474 	qc = __ata_qc_from_tag(ap, tag);
1475 	memcpy(&qc->result_tf, &tf, sizeof(tf));
1476 	qc->result_tf.flags = ATA_TFLAG_ISADDR | ATA_TFLAG_LBA | ATA_TFLAG_LBA48;
1477 	qc->err_mask |= AC_ERR_DEV | AC_ERR_NCQ;
1478 
1479 	/*
1480 	 * If the device supports NCQ autosense, ata_eh_read_log_10h() will have
1481 	 * stored the sense data in qc->result_tf.auxiliary.
1482 	 */
1483 	if (qc->result_tf.auxiliary) {
1484 		char sense_key, asc, ascq;
1485 
1486 		sense_key = (qc->result_tf.auxiliary >> 16) & 0xff;
1487 		asc = (qc->result_tf.auxiliary >> 8) & 0xff;
1488 		ascq = qc->result_tf.auxiliary & 0xff;
1489 		if (ata_scsi_sense_is_valid(sense_key, asc, ascq)) {
1490 			ata_scsi_set_sense(dev, qc->scsicmd, sense_key, asc,
1491 					   ascq);
1492 			ata_scsi_set_sense_information(dev, qc->scsicmd,
1493 						       &qc->result_tf);
1494 			qc->flags |= ATA_QCFLAG_SENSE_VALID;
1495 		}
1496 	}
1497 
1498 	ata_qc_for_each_raw(ap, qc, tag) {
1499 		if (!(qc->flags & ATA_QCFLAG_EH) ||
1500 		    qc->flags & ATA_QCFLAG_EH_SUCCESS_CMD ||
1501 		    ata_dev_phys_link(qc->dev) != link)
1502 			continue;
1503 
1504 		/* Skip the single QC which caused the NCQ error. */
1505 		if (qc->err_mask)
1506 			continue;
1507 
1508 		/*
1509 		 * For SATA, the STATUS and ERROR fields are shared for all NCQ
1510 		 * commands that were completed with the same SDB FIS.
1511 		 * Therefore, we have to clear the ATA_ERR bit for all QCs
1512 		 * except the one that caused the NCQ error.
1513 		 */
1514 		qc->result_tf.status &= ~ATA_ERR;
1515 		qc->result_tf.error = 0;
1516 
1517 		/*
1518 		 * If we get a NCQ error, that means that a single command was
1519 		 * aborted. All other failed commands for our link should be
1520 		 * retried and has no business of going though further scrutiny
1521 		 * by ata_eh_link_autopsy().
1522 		 */
1523 		qc->flags |= ATA_QCFLAG_RETRY;
1524 	}
1525 
1526 	ehc->i.err_mask &= ~AC_ERR_DEV;
1527 }
1528 EXPORT_SYMBOL_GPL(ata_eh_analyze_ncq_error);
1529