xref: /openbmc/linux/drivers/ata/libata-core.c (revision 5a1ea477)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  *  libata-core.c - helper library for ATA
4  *
5  *  Maintained by:  Tejun Heo <tj@kernel.org>
6  *    		    Please ALWAYS copy linux-ide@vger.kernel.org
7  *		    on emails.
8  *
9  *  Copyright 2003-2004 Red Hat, Inc.  All rights reserved.
10  *  Copyright 2003-2004 Jeff Garzik
11  *
12  *  libata documentation is available via 'make {ps|pdf}docs',
13  *  as Documentation/driver-api/libata.rst
14  *
15  *  Hardware documentation available from http://www.t13.org/ and
16  *  http://www.sata-io.org/
17  *
18  *  Standards documents from:
19  *	http://www.t13.org (ATA standards, PCI DMA IDE spec)
20  *	http://www.t10.org (SCSI MMC - for ATAPI MMC)
21  *	http://www.sata-io.org (SATA)
22  *	http://www.compactflash.org (CF)
23  *	http://www.qic.org (QIC157 - Tape and DSC)
24  *	http://www.ce-ata.org (CE-ATA: not supported)
25  */
26 
27 #include <linux/kernel.h>
28 #include <linux/module.h>
29 #include <linux/pci.h>
30 #include <linux/init.h>
31 #include <linux/list.h>
32 #include <linux/mm.h>
33 #include <linux/spinlock.h>
34 #include <linux/blkdev.h>
35 #include <linux/delay.h>
36 #include <linux/timer.h>
37 #include <linux/time.h>
38 #include <linux/interrupt.h>
39 #include <linux/completion.h>
40 #include <linux/suspend.h>
41 #include <linux/workqueue.h>
42 #include <linux/scatterlist.h>
43 #include <linux/io.h>
44 #include <linux/async.h>
45 #include <linux/log2.h>
46 #include <linux/slab.h>
47 #include <linux/glob.h>
48 #include <scsi/scsi.h>
49 #include <scsi/scsi_cmnd.h>
50 #include <scsi/scsi_host.h>
51 #include <linux/libata.h>
52 #include <asm/byteorder.h>
53 #include <asm/unaligned.h>
54 #include <linux/cdrom.h>
55 #include <linux/ratelimit.h>
56 #include <linux/leds.h>
57 #include <linux/pm_runtime.h>
58 #include <linux/platform_device.h>
59 
60 #define CREATE_TRACE_POINTS
61 #include <trace/events/libata.h>
62 
63 #include "libata.h"
64 #include "libata-transport.h"
65 
66 /* debounce timing parameters in msecs { interval, duration, timeout } */
67 const unsigned long sata_deb_timing_normal[]		= {   5,  100, 2000 };
68 const unsigned long sata_deb_timing_hotplug[]		= {  25,  500, 2000 };
69 const unsigned long sata_deb_timing_long[]		= { 100, 2000, 5000 };
70 
71 const struct ata_port_operations ata_base_port_ops = {
72 	.prereset		= ata_std_prereset,
73 	.postreset		= ata_std_postreset,
74 	.error_handler		= ata_std_error_handler,
75 	.sched_eh		= ata_std_sched_eh,
76 	.end_eh			= ata_std_end_eh,
77 };
78 
79 const struct ata_port_operations sata_port_ops = {
80 	.inherits		= &ata_base_port_ops,
81 
82 	.qc_defer		= ata_std_qc_defer,
83 	.hardreset		= sata_std_hardreset,
84 };
85 
86 static unsigned int ata_dev_init_params(struct ata_device *dev,
87 					u16 heads, u16 sectors);
88 static unsigned int ata_dev_set_xfermode(struct ata_device *dev);
89 static void ata_dev_xfermask(struct ata_device *dev);
90 static unsigned long ata_dev_blacklisted(const struct ata_device *dev);
91 
92 atomic_t ata_print_id = ATOMIC_INIT(0);
93 
94 struct ata_force_param {
95 	const char	*name;
96 	unsigned int	cbl;
97 	int		spd_limit;
98 	unsigned long	xfer_mask;
99 	unsigned int	horkage_on;
100 	unsigned int	horkage_off;
101 	unsigned int	lflags;
102 };
103 
104 struct ata_force_ent {
105 	int			port;
106 	int			device;
107 	struct ata_force_param	param;
108 };
109 
110 static struct ata_force_ent *ata_force_tbl;
111 static int ata_force_tbl_size;
112 
113 static char ata_force_param_buf[PAGE_SIZE] __initdata;
114 /* param_buf is thrown away after initialization, disallow read */
115 module_param_string(force, ata_force_param_buf, sizeof(ata_force_param_buf), 0);
116 MODULE_PARM_DESC(force, "Force ATA configurations including cable type, link speed and transfer mode (see Documentation/admin-guide/kernel-parameters.rst for details)");
117 
118 static int atapi_enabled = 1;
119 module_param(atapi_enabled, int, 0444);
120 MODULE_PARM_DESC(atapi_enabled, "Enable discovery of ATAPI devices (0=off, 1=on [default])");
121 
122 static int atapi_dmadir = 0;
123 module_param(atapi_dmadir, int, 0444);
124 MODULE_PARM_DESC(atapi_dmadir, "Enable ATAPI DMADIR bridge support (0=off [default], 1=on)");
125 
126 int atapi_passthru16 = 1;
127 module_param(atapi_passthru16, int, 0444);
128 MODULE_PARM_DESC(atapi_passthru16, "Enable ATA_16 passthru for ATAPI devices (0=off, 1=on [default])");
129 
130 int libata_fua = 0;
131 module_param_named(fua, libata_fua, int, 0444);
132 MODULE_PARM_DESC(fua, "FUA support (0=off [default], 1=on)");
133 
134 static int ata_ignore_hpa;
135 module_param_named(ignore_hpa, ata_ignore_hpa, int, 0644);
136 MODULE_PARM_DESC(ignore_hpa, "Ignore HPA limit (0=keep BIOS limits, 1=ignore limits, using full disk)");
137 
138 static int libata_dma_mask = ATA_DMA_MASK_ATA|ATA_DMA_MASK_ATAPI|ATA_DMA_MASK_CFA;
139 module_param_named(dma, libata_dma_mask, int, 0444);
140 MODULE_PARM_DESC(dma, "DMA enable/disable (0x1==ATA, 0x2==ATAPI, 0x4==CF)");
141 
142 static int ata_probe_timeout;
143 module_param(ata_probe_timeout, int, 0444);
144 MODULE_PARM_DESC(ata_probe_timeout, "Set ATA probing timeout (seconds)");
145 
146 int libata_noacpi = 0;
147 module_param_named(noacpi, libata_noacpi, int, 0444);
148 MODULE_PARM_DESC(noacpi, "Disable the use of ACPI in probe/suspend/resume (0=off [default], 1=on)");
149 
150 int libata_allow_tpm = 0;
151 module_param_named(allow_tpm, libata_allow_tpm, int, 0444);
152 MODULE_PARM_DESC(allow_tpm, "Permit the use of TPM commands (0=off [default], 1=on)");
153 
154 static int atapi_an;
155 module_param(atapi_an, int, 0444);
156 MODULE_PARM_DESC(atapi_an, "Enable ATAPI AN media presence notification (0=0ff [default], 1=on)");
157 
158 MODULE_AUTHOR("Jeff Garzik");
159 MODULE_DESCRIPTION("Library module for ATA devices");
160 MODULE_LICENSE("GPL");
161 MODULE_VERSION(DRV_VERSION);
162 
163 
164 static bool ata_sstatus_online(u32 sstatus)
165 {
166 	return (sstatus & 0xf) == 0x3;
167 }
168 
169 /**
170  *	ata_link_next - link iteration helper
171  *	@link: the previous link, NULL to start
172  *	@ap: ATA port containing links to iterate
173  *	@mode: iteration mode, one of ATA_LITER_*
174  *
175  *	LOCKING:
176  *	Host lock or EH context.
177  *
178  *	RETURNS:
179  *	Pointer to the next link.
180  */
181 struct ata_link *ata_link_next(struct ata_link *link, struct ata_port *ap,
182 			       enum ata_link_iter_mode mode)
183 {
184 	BUG_ON(mode != ATA_LITER_EDGE &&
185 	       mode != ATA_LITER_PMP_FIRST && mode != ATA_LITER_HOST_FIRST);
186 
187 	/* NULL link indicates start of iteration */
188 	if (!link)
189 		switch (mode) {
190 		case ATA_LITER_EDGE:
191 		case ATA_LITER_PMP_FIRST:
192 			if (sata_pmp_attached(ap))
193 				return ap->pmp_link;
194 			/* fall through */
195 		case ATA_LITER_HOST_FIRST:
196 			return &ap->link;
197 		}
198 
199 	/* we just iterated over the host link, what's next? */
200 	if (link == &ap->link)
201 		switch (mode) {
202 		case ATA_LITER_HOST_FIRST:
203 			if (sata_pmp_attached(ap))
204 				return ap->pmp_link;
205 			/* fall through */
206 		case ATA_LITER_PMP_FIRST:
207 			if (unlikely(ap->slave_link))
208 				return ap->slave_link;
209 			/* fall through */
210 		case ATA_LITER_EDGE:
211 			return NULL;
212 		}
213 
214 	/* slave_link excludes PMP */
215 	if (unlikely(link == ap->slave_link))
216 		return NULL;
217 
218 	/* we were over a PMP link */
219 	if (++link < ap->pmp_link + ap->nr_pmp_links)
220 		return link;
221 
222 	if (mode == ATA_LITER_PMP_FIRST)
223 		return &ap->link;
224 
225 	return NULL;
226 }
227 
228 /**
229  *	ata_dev_next - device iteration helper
230  *	@dev: the previous device, NULL to start
231  *	@link: ATA link containing devices to iterate
232  *	@mode: iteration mode, one of ATA_DITER_*
233  *
234  *	LOCKING:
235  *	Host lock or EH context.
236  *
237  *	RETURNS:
238  *	Pointer to the next device.
239  */
240 struct ata_device *ata_dev_next(struct ata_device *dev, struct ata_link *link,
241 				enum ata_dev_iter_mode mode)
242 {
243 	BUG_ON(mode != ATA_DITER_ENABLED && mode != ATA_DITER_ENABLED_REVERSE &&
244 	       mode != ATA_DITER_ALL && mode != ATA_DITER_ALL_REVERSE);
245 
246 	/* NULL dev indicates start of iteration */
247 	if (!dev)
248 		switch (mode) {
249 		case ATA_DITER_ENABLED:
250 		case ATA_DITER_ALL:
251 			dev = link->device;
252 			goto check;
253 		case ATA_DITER_ENABLED_REVERSE:
254 		case ATA_DITER_ALL_REVERSE:
255 			dev = link->device + ata_link_max_devices(link) - 1;
256 			goto check;
257 		}
258 
259  next:
260 	/* move to the next one */
261 	switch (mode) {
262 	case ATA_DITER_ENABLED:
263 	case ATA_DITER_ALL:
264 		if (++dev < link->device + ata_link_max_devices(link))
265 			goto check;
266 		return NULL;
267 	case ATA_DITER_ENABLED_REVERSE:
268 	case ATA_DITER_ALL_REVERSE:
269 		if (--dev >= link->device)
270 			goto check;
271 		return NULL;
272 	}
273 
274  check:
275 	if ((mode == ATA_DITER_ENABLED || mode == ATA_DITER_ENABLED_REVERSE) &&
276 	    !ata_dev_enabled(dev))
277 		goto next;
278 	return dev;
279 }
280 
281 /**
282  *	ata_dev_phys_link - find physical link for a device
283  *	@dev: ATA device to look up physical link for
284  *
285  *	Look up physical link which @dev is attached to.  Note that
286  *	this is different from @dev->link only when @dev is on slave
287  *	link.  For all other cases, it's the same as @dev->link.
288  *
289  *	LOCKING:
290  *	Don't care.
291  *
292  *	RETURNS:
293  *	Pointer to the found physical link.
294  */
295 struct ata_link *ata_dev_phys_link(struct ata_device *dev)
296 {
297 	struct ata_port *ap = dev->link->ap;
298 
299 	if (!ap->slave_link)
300 		return dev->link;
301 	if (!dev->devno)
302 		return &ap->link;
303 	return ap->slave_link;
304 }
305 
306 /**
307  *	ata_force_cbl - force cable type according to libata.force
308  *	@ap: ATA port of interest
309  *
310  *	Force cable type according to libata.force and whine about it.
311  *	The last entry which has matching port number is used, so it
312  *	can be specified as part of device force parameters.  For
313  *	example, both "a:40c,1.00:udma4" and "1.00:40c,udma4" have the
314  *	same effect.
315  *
316  *	LOCKING:
317  *	EH context.
318  */
319 void ata_force_cbl(struct ata_port *ap)
320 {
321 	int i;
322 
323 	for (i = ata_force_tbl_size - 1; i >= 0; i--) {
324 		const struct ata_force_ent *fe = &ata_force_tbl[i];
325 
326 		if (fe->port != -1 && fe->port != ap->print_id)
327 			continue;
328 
329 		if (fe->param.cbl == ATA_CBL_NONE)
330 			continue;
331 
332 		ap->cbl = fe->param.cbl;
333 		ata_port_notice(ap, "FORCE: cable set to %s\n", fe->param.name);
334 		return;
335 	}
336 }
337 
338 /**
339  *	ata_force_link_limits - force link limits according to libata.force
340  *	@link: ATA link of interest
341  *
342  *	Force link flags and SATA spd limit according to libata.force
343  *	and whine about it.  When only the port part is specified
344  *	(e.g. 1:), the limit applies to all links connected to both
345  *	the host link and all fan-out ports connected via PMP.  If the
346  *	device part is specified as 0 (e.g. 1.00:), it specifies the
347  *	first fan-out link not the host link.  Device number 15 always
348  *	points to the host link whether PMP is attached or not.  If the
349  *	controller has slave link, device number 16 points to it.
350  *
351  *	LOCKING:
352  *	EH context.
353  */
354 static void ata_force_link_limits(struct ata_link *link)
355 {
356 	bool did_spd = false;
357 	int linkno = link->pmp;
358 	int i;
359 
360 	if (ata_is_host_link(link))
361 		linkno += 15;
362 
363 	for (i = ata_force_tbl_size - 1; i >= 0; i--) {
364 		const struct ata_force_ent *fe = &ata_force_tbl[i];
365 
366 		if (fe->port != -1 && fe->port != link->ap->print_id)
367 			continue;
368 
369 		if (fe->device != -1 && fe->device != linkno)
370 			continue;
371 
372 		/* only honor the first spd limit */
373 		if (!did_spd && fe->param.spd_limit) {
374 			link->hw_sata_spd_limit = (1 << fe->param.spd_limit) - 1;
375 			ata_link_notice(link, "FORCE: PHY spd limit set to %s\n",
376 					fe->param.name);
377 			did_spd = true;
378 		}
379 
380 		/* let lflags stack */
381 		if (fe->param.lflags) {
382 			link->flags |= fe->param.lflags;
383 			ata_link_notice(link,
384 					"FORCE: link flag 0x%x forced -> 0x%x\n",
385 					fe->param.lflags, link->flags);
386 		}
387 	}
388 }
389 
390 /**
391  *	ata_force_xfermask - force xfermask according to libata.force
392  *	@dev: ATA device of interest
393  *
394  *	Force xfer_mask according to libata.force and whine about it.
395  *	For consistency with link selection, device number 15 selects
396  *	the first device connected to the host link.
397  *
398  *	LOCKING:
399  *	EH context.
400  */
401 static void ata_force_xfermask(struct ata_device *dev)
402 {
403 	int devno = dev->link->pmp + dev->devno;
404 	int alt_devno = devno;
405 	int i;
406 
407 	/* allow n.15/16 for devices attached to host port */
408 	if (ata_is_host_link(dev->link))
409 		alt_devno += 15;
410 
411 	for (i = ata_force_tbl_size - 1; i >= 0; i--) {
412 		const struct ata_force_ent *fe = &ata_force_tbl[i];
413 		unsigned long pio_mask, mwdma_mask, udma_mask;
414 
415 		if (fe->port != -1 && fe->port != dev->link->ap->print_id)
416 			continue;
417 
418 		if (fe->device != -1 && fe->device != devno &&
419 		    fe->device != alt_devno)
420 			continue;
421 
422 		if (!fe->param.xfer_mask)
423 			continue;
424 
425 		ata_unpack_xfermask(fe->param.xfer_mask,
426 				    &pio_mask, &mwdma_mask, &udma_mask);
427 		if (udma_mask)
428 			dev->udma_mask = udma_mask;
429 		else if (mwdma_mask) {
430 			dev->udma_mask = 0;
431 			dev->mwdma_mask = mwdma_mask;
432 		} else {
433 			dev->udma_mask = 0;
434 			dev->mwdma_mask = 0;
435 			dev->pio_mask = pio_mask;
436 		}
437 
438 		ata_dev_notice(dev, "FORCE: xfer_mask set to %s\n",
439 			       fe->param.name);
440 		return;
441 	}
442 }
443 
444 /**
445  *	ata_force_horkage - force horkage according to libata.force
446  *	@dev: ATA device of interest
447  *
448  *	Force horkage according to libata.force and whine about it.
449  *	For consistency with link selection, device number 15 selects
450  *	the first device connected to the host link.
451  *
452  *	LOCKING:
453  *	EH context.
454  */
455 static void ata_force_horkage(struct ata_device *dev)
456 {
457 	int devno = dev->link->pmp + dev->devno;
458 	int alt_devno = devno;
459 	int i;
460 
461 	/* allow n.15/16 for devices attached to host port */
462 	if (ata_is_host_link(dev->link))
463 		alt_devno += 15;
464 
465 	for (i = 0; i < ata_force_tbl_size; i++) {
466 		const struct ata_force_ent *fe = &ata_force_tbl[i];
467 
468 		if (fe->port != -1 && fe->port != dev->link->ap->print_id)
469 			continue;
470 
471 		if (fe->device != -1 && fe->device != devno &&
472 		    fe->device != alt_devno)
473 			continue;
474 
475 		if (!(~dev->horkage & fe->param.horkage_on) &&
476 		    !(dev->horkage & fe->param.horkage_off))
477 			continue;
478 
479 		dev->horkage |= fe->param.horkage_on;
480 		dev->horkage &= ~fe->param.horkage_off;
481 
482 		ata_dev_notice(dev, "FORCE: horkage modified (%s)\n",
483 			       fe->param.name);
484 	}
485 }
486 
487 /**
488  *	atapi_cmd_type - Determine ATAPI command type from SCSI opcode
489  *	@opcode: SCSI opcode
490  *
491  *	Determine ATAPI command type from @opcode.
492  *
493  *	LOCKING:
494  *	None.
495  *
496  *	RETURNS:
497  *	ATAPI_{READ|WRITE|READ_CD|PASS_THRU|MISC}
498  */
499 int atapi_cmd_type(u8 opcode)
500 {
501 	switch (opcode) {
502 	case GPCMD_READ_10:
503 	case GPCMD_READ_12:
504 		return ATAPI_READ;
505 
506 	case GPCMD_WRITE_10:
507 	case GPCMD_WRITE_12:
508 	case GPCMD_WRITE_AND_VERIFY_10:
509 		return ATAPI_WRITE;
510 
511 	case GPCMD_READ_CD:
512 	case GPCMD_READ_CD_MSF:
513 		return ATAPI_READ_CD;
514 
515 	case ATA_16:
516 	case ATA_12:
517 		if (atapi_passthru16)
518 			return ATAPI_PASS_THRU;
519 		/* fall thru */
520 	default:
521 		return ATAPI_MISC;
522 	}
523 }
524 
525 /**
526  *	ata_tf_to_fis - Convert ATA taskfile to SATA FIS structure
527  *	@tf: Taskfile to convert
528  *	@pmp: Port multiplier port
529  *	@is_cmd: This FIS is for command
530  *	@fis: Buffer into which data will output
531  *
532  *	Converts a standard ATA taskfile to a Serial ATA
533  *	FIS structure (Register - Host to Device).
534  *
535  *	LOCKING:
536  *	Inherited from caller.
537  */
538 void ata_tf_to_fis(const struct ata_taskfile *tf, u8 pmp, int is_cmd, u8 *fis)
539 {
540 	fis[0] = 0x27;			/* Register - Host to Device FIS */
541 	fis[1] = pmp & 0xf;		/* Port multiplier number*/
542 	if (is_cmd)
543 		fis[1] |= (1 << 7);	/* bit 7 indicates Command FIS */
544 
545 	fis[2] = tf->command;
546 	fis[3] = tf->feature;
547 
548 	fis[4] = tf->lbal;
549 	fis[5] = tf->lbam;
550 	fis[6] = tf->lbah;
551 	fis[7] = tf->device;
552 
553 	fis[8] = tf->hob_lbal;
554 	fis[9] = tf->hob_lbam;
555 	fis[10] = tf->hob_lbah;
556 	fis[11] = tf->hob_feature;
557 
558 	fis[12] = tf->nsect;
559 	fis[13] = tf->hob_nsect;
560 	fis[14] = 0;
561 	fis[15] = tf->ctl;
562 
563 	fis[16] = tf->auxiliary & 0xff;
564 	fis[17] = (tf->auxiliary >> 8) & 0xff;
565 	fis[18] = (tf->auxiliary >> 16) & 0xff;
566 	fis[19] = (tf->auxiliary >> 24) & 0xff;
567 }
568 
569 /**
570  *	ata_tf_from_fis - Convert SATA FIS to ATA taskfile
571  *	@fis: Buffer from which data will be input
572  *	@tf: Taskfile to output
573  *
574  *	Converts a serial ATA FIS structure to a standard ATA taskfile.
575  *
576  *	LOCKING:
577  *	Inherited from caller.
578  */
579 
580 void ata_tf_from_fis(const u8 *fis, struct ata_taskfile *tf)
581 {
582 	tf->command	= fis[2];	/* status */
583 	tf->feature	= fis[3];	/* error */
584 
585 	tf->lbal	= fis[4];
586 	tf->lbam	= fis[5];
587 	tf->lbah	= fis[6];
588 	tf->device	= fis[7];
589 
590 	tf->hob_lbal	= fis[8];
591 	tf->hob_lbam	= fis[9];
592 	tf->hob_lbah	= fis[10];
593 
594 	tf->nsect	= fis[12];
595 	tf->hob_nsect	= fis[13];
596 }
597 
598 static const u8 ata_rw_cmds[] = {
599 	/* pio multi */
600 	ATA_CMD_READ_MULTI,
601 	ATA_CMD_WRITE_MULTI,
602 	ATA_CMD_READ_MULTI_EXT,
603 	ATA_CMD_WRITE_MULTI_EXT,
604 	0,
605 	0,
606 	0,
607 	ATA_CMD_WRITE_MULTI_FUA_EXT,
608 	/* pio */
609 	ATA_CMD_PIO_READ,
610 	ATA_CMD_PIO_WRITE,
611 	ATA_CMD_PIO_READ_EXT,
612 	ATA_CMD_PIO_WRITE_EXT,
613 	0,
614 	0,
615 	0,
616 	0,
617 	/* dma */
618 	ATA_CMD_READ,
619 	ATA_CMD_WRITE,
620 	ATA_CMD_READ_EXT,
621 	ATA_CMD_WRITE_EXT,
622 	0,
623 	0,
624 	0,
625 	ATA_CMD_WRITE_FUA_EXT
626 };
627 
628 /**
629  *	ata_rwcmd_protocol - set taskfile r/w commands and protocol
630  *	@tf: command to examine and configure
631  *	@dev: device tf belongs to
632  *
633  *	Examine the device configuration and tf->flags to calculate
634  *	the proper read/write commands and protocol to use.
635  *
636  *	LOCKING:
637  *	caller.
638  */
639 static int ata_rwcmd_protocol(struct ata_taskfile *tf, struct ata_device *dev)
640 {
641 	u8 cmd;
642 
643 	int index, fua, lba48, write;
644 
645 	fua = (tf->flags & ATA_TFLAG_FUA) ? 4 : 0;
646 	lba48 = (tf->flags & ATA_TFLAG_LBA48) ? 2 : 0;
647 	write = (tf->flags & ATA_TFLAG_WRITE) ? 1 : 0;
648 
649 	if (dev->flags & ATA_DFLAG_PIO) {
650 		tf->protocol = ATA_PROT_PIO;
651 		index = dev->multi_count ? 0 : 8;
652 	} else if (lba48 && (dev->link->ap->flags & ATA_FLAG_PIO_LBA48)) {
653 		/* Unable to use DMA due to host limitation */
654 		tf->protocol = ATA_PROT_PIO;
655 		index = dev->multi_count ? 0 : 8;
656 	} else {
657 		tf->protocol = ATA_PROT_DMA;
658 		index = 16;
659 	}
660 
661 	cmd = ata_rw_cmds[index + fua + lba48 + write];
662 	if (cmd) {
663 		tf->command = cmd;
664 		return 0;
665 	}
666 	return -1;
667 }
668 
669 /**
670  *	ata_tf_read_block - Read block address from ATA taskfile
671  *	@tf: ATA taskfile of interest
672  *	@dev: ATA device @tf belongs to
673  *
674  *	LOCKING:
675  *	None.
676  *
677  *	Read block address from @tf.  This function can handle all
678  *	three address formats - LBA, LBA48 and CHS.  tf->protocol and
679  *	flags select the address format to use.
680  *
681  *	RETURNS:
682  *	Block address read from @tf.
683  */
684 u64 ata_tf_read_block(const struct ata_taskfile *tf, struct ata_device *dev)
685 {
686 	u64 block = 0;
687 
688 	if (tf->flags & ATA_TFLAG_LBA) {
689 		if (tf->flags & ATA_TFLAG_LBA48) {
690 			block |= (u64)tf->hob_lbah << 40;
691 			block |= (u64)tf->hob_lbam << 32;
692 			block |= (u64)tf->hob_lbal << 24;
693 		} else
694 			block |= (tf->device & 0xf) << 24;
695 
696 		block |= tf->lbah << 16;
697 		block |= tf->lbam << 8;
698 		block |= tf->lbal;
699 	} else {
700 		u32 cyl, head, sect;
701 
702 		cyl = tf->lbam | (tf->lbah << 8);
703 		head = tf->device & 0xf;
704 		sect = tf->lbal;
705 
706 		if (!sect) {
707 			ata_dev_warn(dev,
708 				     "device reported invalid CHS sector 0\n");
709 			return U64_MAX;
710 		}
711 
712 		block = (cyl * dev->heads + head) * dev->sectors + sect - 1;
713 	}
714 
715 	return block;
716 }
717 
718 /**
719  *	ata_build_rw_tf - Build ATA taskfile for given read/write request
720  *	@tf: Target ATA taskfile
721  *	@dev: ATA device @tf belongs to
722  *	@block: Block address
723  *	@n_block: Number of blocks
724  *	@tf_flags: RW/FUA etc...
725  *	@tag: tag
726  *	@class: IO priority class
727  *
728  *	LOCKING:
729  *	None.
730  *
731  *	Build ATA taskfile @tf for read/write request described by
732  *	@block, @n_block, @tf_flags and @tag on @dev.
733  *
734  *	RETURNS:
735  *
736  *	0 on success, -ERANGE if the request is too large for @dev,
737  *	-EINVAL if the request is invalid.
738  */
739 int ata_build_rw_tf(struct ata_taskfile *tf, struct ata_device *dev,
740 		    u64 block, u32 n_block, unsigned int tf_flags,
741 		    unsigned int tag, int class)
742 {
743 	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
744 	tf->flags |= tf_flags;
745 
746 	if (ata_ncq_enabled(dev) && !ata_tag_internal(tag)) {
747 		/* yay, NCQ */
748 		if (!lba_48_ok(block, n_block))
749 			return -ERANGE;
750 
751 		tf->protocol = ATA_PROT_NCQ;
752 		tf->flags |= ATA_TFLAG_LBA | ATA_TFLAG_LBA48;
753 
754 		if (tf->flags & ATA_TFLAG_WRITE)
755 			tf->command = ATA_CMD_FPDMA_WRITE;
756 		else
757 			tf->command = ATA_CMD_FPDMA_READ;
758 
759 		tf->nsect = tag << 3;
760 		tf->hob_feature = (n_block >> 8) & 0xff;
761 		tf->feature = n_block & 0xff;
762 
763 		tf->hob_lbah = (block >> 40) & 0xff;
764 		tf->hob_lbam = (block >> 32) & 0xff;
765 		tf->hob_lbal = (block >> 24) & 0xff;
766 		tf->lbah = (block >> 16) & 0xff;
767 		tf->lbam = (block >> 8) & 0xff;
768 		tf->lbal = block & 0xff;
769 
770 		tf->device = ATA_LBA;
771 		if (tf->flags & ATA_TFLAG_FUA)
772 			tf->device |= 1 << 7;
773 
774 		if (dev->flags & ATA_DFLAG_NCQ_PRIO) {
775 			if (class == IOPRIO_CLASS_RT)
776 				tf->hob_nsect |= ATA_PRIO_HIGH <<
777 						 ATA_SHIFT_PRIO;
778 		}
779 	} else if (dev->flags & ATA_DFLAG_LBA) {
780 		tf->flags |= ATA_TFLAG_LBA;
781 
782 		if (lba_28_ok(block, n_block)) {
783 			/* use LBA28 */
784 			tf->device |= (block >> 24) & 0xf;
785 		} else if (lba_48_ok(block, n_block)) {
786 			if (!(dev->flags & ATA_DFLAG_LBA48))
787 				return -ERANGE;
788 
789 			/* use LBA48 */
790 			tf->flags |= ATA_TFLAG_LBA48;
791 
792 			tf->hob_nsect = (n_block >> 8) & 0xff;
793 
794 			tf->hob_lbah = (block >> 40) & 0xff;
795 			tf->hob_lbam = (block >> 32) & 0xff;
796 			tf->hob_lbal = (block >> 24) & 0xff;
797 		} else
798 			/* request too large even for LBA48 */
799 			return -ERANGE;
800 
801 		if (unlikely(ata_rwcmd_protocol(tf, dev) < 0))
802 			return -EINVAL;
803 
804 		tf->nsect = n_block & 0xff;
805 
806 		tf->lbah = (block >> 16) & 0xff;
807 		tf->lbam = (block >> 8) & 0xff;
808 		tf->lbal = block & 0xff;
809 
810 		tf->device |= ATA_LBA;
811 	} else {
812 		/* CHS */
813 		u32 sect, head, cyl, track;
814 
815 		/* The request -may- be too large for CHS addressing. */
816 		if (!lba_28_ok(block, n_block))
817 			return -ERANGE;
818 
819 		if (unlikely(ata_rwcmd_protocol(tf, dev) < 0))
820 			return -EINVAL;
821 
822 		/* Convert LBA to CHS */
823 		track = (u32)block / dev->sectors;
824 		cyl   = track / dev->heads;
825 		head  = track % dev->heads;
826 		sect  = (u32)block % dev->sectors + 1;
827 
828 		DPRINTK("block %u track %u cyl %u head %u sect %u\n",
829 			(u32)block, track, cyl, head, sect);
830 
831 		/* Check whether the converted CHS can fit.
832 		   Cylinder: 0-65535
833 		   Head: 0-15
834 		   Sector: 1-255*/
835 		if ((cyl >> 16) || (head >> 4) || (sect >> 8) || (!sect))
836 			return -ERANGE;
837 
838 		tf->nsect = n_block & 0xff; /* Sector count 0 means 256 sectors */
839 		tf->lbal = sect;
840 		tf->lbam = cyl;
841 		tf->lbah = cyl >> 8;
842 		tf->device |= head;
843 	}
844 
845 	return 0;
846 }
847 
848 /**
849  *	ata_pack_xfermask - Pack pio, mwdma and udma masks into xfer_mask
850  *	@pio_mask: pio_mask
851  *	@mwdma_mask: mwdma_mask
852  *	@udma_mask: udma_mask
853  *
854  *	Pack @pio_mask, @mwdma_mask and @udma_mask into a single
855  *	unsigned int xfer_mask.
856  *
857  *	LOCKING:
858  *	None.
859  *
860  *	RETURNS:
861  *	Packed xfer_mask.
862  */
863 unsigned long ata_pack_xfermask(unsigned long pio_mask,
864 				unsigned long mwdma_mask,
865 				unsigned long udma_mask)
866 {
867 	return ((pio_mask << ATA_SHIFT_PIO) & ATA_MASK_PIO) |
868 		((mwdma_mask << ATA_SHIFT_MWDMA) & ATA_MASK_MWDMA) |
869 		((udma_mask << ATA_SHIFT_UDMA) & ATA_MASK_UDMA);
870 }
871 
872 /**
873  *	ata_unpack_xfermask - Unpack xfer_mask into pio, mwdma and udma masks
874  *	@xfer_mask: xfer_mask to unpack
875  *	@pio_mask: resulting pio_mask
876  *	@mwdma_mask: resulting mwdma_mask
877  *	@udma_mask: resulting udma_mask
878  *
879  *	Unpack @xfer_mask into @pio_mask, @mwdma_mask and @udma_mask.
880  *	Any NULL destination masks will be ignored.
881  */
882 void ata_unpack_xfermask(unsigned long xfer_mask, unsigned long *pio_mask,
883 			 unsigned long *mwdma_mask, unsigned long *udma_mask)
884 {
885 	if (pio_mask)
886 		*pio_mask = (xfer_mask & ATA_MASK_PIO) >> ATA_SHIFT_PIO;
887 	if (mwdma_mask)
888 		*mwdma_mask = (xfer_mask & ATA_MASK_MWDMA) >> ATA_SHIFT_MWDMA;
889 	if (udma_mask)
890 		*udma_mask = (xfer_mask & ATA_MASK_UDMA) >> ATA_SHIFT_UDMA;
891 }
892 
893 static const struct ata_xfer_ent {
894 	int shift, bits;
895 	u8 base;
896 } ata_xfer_tbl[] = {
897 	{ ATA_SHIFT_PIO, ATA_NR_PIO_MODES, XFER_PIO_0 },
898 	{ ATA_SHIFT_MWDMA, ATA_NR_MWDMA_MODES, XFER_MW_DMA_0 },
899 	{ ATA_SHIFT_UDMA, ATA_NR_UDMA_MODES, XFER_UDMA_0 },
900 	{ -1, },
901 };
902 
903 /**
904  *	ata_xfer_mask2mode - Find matching XFER_* for the given xfer_mask
905  *	@xfer_mask: xfer_mask of interest
906  *
907  *	Return matching XFER_* value for @xfer_mask.  Only the highest
908  *	bit of @xfer_mask is considered.
909  *
910  *	LOCKING:
911  *	None.
912  *
913  *	RETURNS:
914  *	Matching XFER_* value, 0xff if no match found.
915  */
916 u8 ata_xfer_mask2mode(unsigned long xfer_mask)
917 {
918 	int highbit = fls(xfer_mask) - 1;
919 	const struct ata_xfer_ent *ent;
920 
921 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
922 		if (highbit >= ent->shift && highbit < ent->shift + ent->bits)
923 			return ent->base + highbit - ent->shift;
924 	return 0xff;
925 }
926 
927 /**
928  *	ata_xfer_mode2mask - Find matching xfer_mask for XFER_*
929  *	@xfer_mode: XFER_* of interest
930  *
931  *	Return matching xfer_mask for @xfer_mode.
932  *
933  *	LOCKING:
934  *	None.
935  *
936  *	RETURNS:
937  *	Matching xfer_mask, 0 if no match found.
938  */
939 unsigned long ata_xfer_mode2mask(u8 xfer_mode)
940 {
941 	const struct ata_xfer_ent *ent;
942 
943 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
944 		if (xfer_mode >= ent->base && xfer_mode < ent->base + ent->bits)
945 			return ((2 << (ent->shift + xfer_mode - ent->base)) - 1)
946 				& ~((1 << ent->shift) - 1);
947 	return 0;
948 }
949 
950 /**
951  *	ata_xfer_mode2shift - Find matching xfer_shift for XFER_*
952  *	@xfer_mode: XFER_* of interest
953  *
954  *	Return matching xfer_shift for @xfer_mode.
955  *
956  *	LOCKING:
957  *	None.
958  *
959  *	RETURNS:
960  *	Matching xfer_shift, -1 if no match found.
961  */
962 int ata_xfer_mode2shift(unsigned long xfer_mode)
963 {
964 	const struct ata_xfer_ent *ent;
965 
966 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
967 		if (xfer_mode >= ent->base && xfer_mode < ent->base + ent->bits)
968 			return ent->shift;
969 	return -1;
970 }
971 
972 /**
973  *	ata_mode_string - convert xfer_mask to string
974  *	@xfer_mask: mask of bits supported; only highest bit counts.
975  *
976  *	Determine string which represents the highest speed
977  *	(highest bit in @modemask).
978  *
979  *	LOCKING:
980  *	None.
981  *
982  *	RETURNS:
983  *	Constant C string representing highest speed listed in
984  *	@mode_mask, or the constant C string "<n/a>".
985  */
986 const char *ata_mode_string(unsigned long xfer_mask)
987 {
988 	static const char * const xfer_mode_str[] = {
989 		"PIO0",
990 		"PIO1",
991 		"PIO2",
992 		"PIO3",
993 		"PIO4",
994 		"PIO5",
995 		"PIO6",
996 		"MWDMA0",
997 		"MWDMA1",
998 		"MWDMA2",
999 		"MWDMA3",
1000 		"MWDMA4",
1001 		"UDMA/16",
1002 		"UDMA/25",
1003 		"UDMA/33",
1004 		"UDMA/44",
1005 		"UDMA/66",
1006 		"UDMA/100",
1007 		"UDMA/133",
1008 		"UDMA7",
1009 	};
1010 	int highbit;
1011 
1012 	highbit = fls(xfer_mask) - 1;
1013 	if (highbit >= 0 && highbit < ARRAY_SIZE(xfer_mode_str))
1014 		return xfer_mode_str[highbit];
1015 	return "<n/a>";
1016 }
1017 
1018 const char *sata_spd_string(unsigned int spd)
1019 {
1020 	static const char * const spd_str[] = {
1021 		"1.5 Gbps",
1022 		"3.0 Gbps",
1023 		"6.0 Gbps",
1024 	};
1025 
1026 	if (spd == 0 || (spd - 1) >= ARRAY_SIZE(spd_str))
1027 		return "<unknown>";
1028 	return spd_str[spd - 1];
1029 }
1030 
1031 /**
1032  *	ata_dev_classify - determine device type based on ATA-spec signature
1033  *	@tf: ATA taskfile register set for device to be identified
1034  *
1035  *	Determine from taskfile register contents whether a device is
1036  *	ATA or ATAPI, as per "Signature and persistence" section
1037  *	of ATA/PI spec (volume 1, sect 5.14).
1038  *
1039  *	LOCKING:
1040  *	None.
1041  *
1042  *	RETURNS:
1043  *	Device type, %ATA_DEV_ATA, %ATA_DEV_ATAPI, %ATA_DEV_PMP,
1044  *	%ATA_DEV_ZAC, or %ATA_DEV_UNKNOWN the event of failure.
1045  */
1046 unsigned int ata_dev_classify(const struct ata_taskfile *tf)
1047 {
1048 	/* Apple's open source Darwin code hints that some devices only
1049 	 * put a proper signature into the LBA mid/high registers,
1050 	 * So, we only check those.  It's sufficient for uniqueness.
1051 	 *
1052 	 * ATA/ATAPI-7 (d1532v1r1: Feb. 19, 2003) specified separate
1053 	 * signatures for ATA and ATAPI devices attached on SerialATA,
1054 	 * 0x3c/0xc3 and 0x69/0x96 respectively.  However, SerialATA
1055 	 * spec has never mentioned about using different signatures
1056 	 * for ATA/ATAPI devices.  Then, Serial ATA II: Port
1057 	 * Multiplier specification began to use 0x69/0x96 to identify
1058 	 * port multpliers and 0x3c/0xc3 to identify SEMB device.
1059 	 * ATA/ATAPI-7 dropped descriptions about 0x3c/0xc3 and
1060 	 * 0x69/0x96 shortly and described them as reserved for
1061 	 * SerialATA.
1062 	 *
1063 	 * We follow the current spec and consider that 0x69/0x96
1064 	 * identifies a port multiplier and 0x3c/0xc3 a SEMB device.
1065 	 * Unfortunately, WDC WD1600JS-62MHB5 (a hard drive) reports
1066 	 * SEMB signature.  This is worked around in
1067 	 * ata_dev_read_id().
1068 	 */
1069 	if ((tf->lbam == 0) && (tf->lbah == 0)) {
1070 		DPRINTK("found ATA device by sig\n");
1071 		return ATA_DEV_ATA;
1072 	}
1073 
1074 	if ((tf->lbam == 0x14) && (tf->lbah == 0xeb)) {
1075 		DPRINTK("found ATAPI device by sig\n");
1076 		return ATA_DEV_ATAPI;
1077 	}
1078 
1079 	if ((tf->lbam == 0x69) && (tf->lbah == 0x96)) {
1080 		DPRINTK("found PMP device by sig\n");
1081 		return ATA_DEV_PMP;
1082 	}
1083 
1084 	if ((tf->lbam == 0x3c) && (tf->lbah == 0xc3)) {
1085 		DPRINTK("found SEMB device by sig (could be ATA device)\n");
1086 		return ATA_DEV_SEMB;
1087 	}
1088 
1089 	if ((tf->lbam == 0xcd) && (tf->lbah == 0xab)) {
1090 		DPRINTK("found ZAC device by sig\n");
1091 		return ATA_DEV_ZAC;
1092 	}
1093 
1094 	DPRINTK("unknown device\n");
1095 	return ATA_DEV_UNKNOWN;
1096 }
1097 
1098 /**
1099  *	ata_id_string - Convert IDENTIFY DEVICE page into string
1100  *	@id: IDENTIFY DEVICE results we will examine
1101  *	@s: string into which data is output
1102  *	@ofs: offset into identify device page
1103  *	@len: length of string to return. must be an even number.
1104  *
1105  *	The strings in the IDENTIFY DEVICE page are broken up into
1106  *	16-bit chunks.  Run through the string, and output each
1107  *	8-bit chunk linearly, regardless of platform.
1108  *
1109  *	LOCKING:
1110  *	caller.
1111  */
1112 
1113 void ata_id_string(const u16 *id, unsigned char *s,
1114 		   unsigned int ofs, unsigned int len)
1115 {
1116 	unsigned int c;
1117 
1118 	BUG_ON(len & 1);
1119 
1120 	while (len > 0) {
1121 		c = id[ofs] >> 8;
1122 		*s = c;
1123 		s++;
1124 
1125 		c = id[ofs] & 0xff;
1126 		*s = c;
1127 		s++;
1128 
1129 		ofs++;
1130 		len -= 2;
1131 	}
1132 }
1133 
1134 /**
1135  *	ata_id_c_string - Convert IDENTIFY DEVICE page into C string
1136  *	@id: IDENTIFY DEVICE results we will examine
1137  *	@s: string into which data is output
1138  *	@ofs: offset into identify device page
1139  *	@len: length of string to return. must be an odd number.
1140  *
1141  *	This function is identical to ata_id_string except that it
1142  *	trims trailing spaces and terminates the resulting string with
1143  *	null.  @len must be actual maximum length (even number) + 1.
1144  *
1145  *	LOCKING:
1146  *	caller.
1147  */
1148 void ata_id_c_string(const u16 *id, unsigned char *s,
1149 		     unsigned int ofs, unsigned int len)
1150 {
1151 	unsigned char *p;
1152 
1153 	ata_id_string(id, s, ofs, len - 1);
1154 
1155 	p = s + strnlen(s, len - 1);
1156 	while (p > s && p[-1] == ' ')
1157 		p--;
1158 	*p = '\0';
1159 }
1160 
1161 static u64 ata_id_n_sectors(const u16 *id)
1162 {
1163 	if (ata_id_has_lba(id)) {
1164 		if (ata_id_has_lba48(id))
1165 			return ata_id_u64(id, ATA_ID_LBA_CAPACITY_2);
1166 		else
1167 			return ata_id_u32(id, ATA_ID_LBA_CAPACITY);
1168 	} else {
1169 		if (ata_id_current_chs_valid(id))
1170 			return id[ATA_ID_CUR_CYLS] * id[ATA_ID_CUR_HEADS] *
1171 			       id[ATA_ID_CUR_SECTORS];
1172 		else
1173 			return id[ATA_ID_CYLS] * id[ATA_ID_HEADS] *
1174 			       id[ATA_ID_SECTORS];
1175 	}
1176 }
1177 
1178 u64 ata_tf_to_lba48(const struct ata_taskfile *tf)
1179 {
1180 	u64 sectors = 0;
1181 
1182 	sectors |= ((u64)(tf->hob_lbah & 0xff)) << 40;
1183 	sectors |= ((u64)(tf->hob_lbam & 0xff)) << 32;
1184 	sectors |= ((u64)(tf->hob_lbal & 0xff)) << 24;
1185 	sectors |= (tf->lbah & 0xff) << 16;
1186 	sectors |= (tf->lbam & 0xff) << 8;
1187 	sectors |= (tf->lbal & 0xff);
1188 
1189 	return sectors;
1190 }
1191 
1192 u64 ata_tf_to_lba(const struct ata_taskfile *tf)
1193 {
1194 	u64 sectors = 0;
1195 
1196 	sectors |= (tf->device & 0x0f) << 24;
1197 	sectors |= (tf->lbah & 0xff) << 16;
1198 	sectors |= (tf->lbam & 0xff) << 8;
1199 	sectors |= (tf->lbal & 0xff);
1200 
1201 	return sectors;
1202 }
1203 
1204 /**
1205  *	ata_read_native_max_address - Read native max address
1206  *	@dev: target device
1207  *	@max_sectors: out parameter for the result native max address
1208  *
1209  *	Perform an LBA48 or LBA28 native size query upon the device in
1210  *	question.
1211  *
1212  *	RETURNS:
1213  *	0 on success, -EACCES if command is aborted by the drive.
1214  *	-EIO on other errors.
1215  */
1216 static int ata_read_native_max_address(struct ata_device *dev, u64 *max_sectors)
1217 {
1218 	unsigned int err_mask;
1219 	struct ata_taskfile tf;
1220 	int lba48 = ata_id_has_lba48(dev->id);
1221 
1222 	ata_tf_init(dev, &tf);
1223 
1224 	/* always clear all address registers */
1225 	tf.flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
1226 
1227 	if (lba48) {
1228 		tf.command = ATA_CMD_READ_NATIVE_MAX_EXT;
1229 		tf.flags |= ATA_TFLAG_LBA48;
1230 	} else
1231 		tf.command = ATA_CMD_READ_NATIVE_MAX;
1232 
1233 	tf.protocol = ATA_PROT_NODATA;
1234 	tf.device |= ATA_LBA;
1235 
1236 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
1237 	if (err_mask) {
1238 		ata_dev_warn(dev,
1239 			     "failed to read native max address (err_mask=0x%x)\n",
1240 			     err_mask);
1241 		if (err_mask == AC_ERR_DEV && (tf.feature & ATA_ABORTED))
1242 			return -EACCES;
1243 		return -EIO;
1244 	}
1245 
1246 	if (lba48)
1247 		*max_sectors = ata_tf_to_lba48(&tf) + 1;
1248 	else
1249 		*max_sectors = ata_tf_to_lba(&tf) + 1;
1250 	if (dev->horkage & ATA_HORKAGE_HPA_SIZE)
1251 		(*max_sectors)--;
1252 	return 0;
1253 }
1254 
1255 /**
1256  *	ata_set_max_sectors - Set max sectors
1257  *	@dev: target device
1258  *	@new_sectors: new max sectors value to set for the device
1259  *
1260  *	Set max sectors of @dev to @new_sectors.
1261  *
1262  *	RETURNS:
1263  *	0 on success, -EACCES if command is aborted or denied (due to
1264  *	previous non-volatile SET_MAX) by the drive.  -EIO on other
1265  *	errors.
1266  */
1267 static int ata_set_max_sectors(struct ata_device *dev, u64 new_sectors)
1268 {
1269 	unsigned int err_mask;
1270 	struct ata_taskfile tf;
1271 	int lba48 = ata_id_has_lba48(dev->id);
1272 
1273 	new_sectors--;
1274 
1275 	ata_tf_init(dev, &tf);
1276 
1277 	tf.flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
1278 
1279 	if (lba48) {
1280 		tf.command = ATA_CMD_SET_MAX_EXT;
1281 		tf.flags |= ATA_TFLAG_LBA48;
1282 
1283 		tf.hob_lbal = (new_sectors >> 24) & 0xff;
1284 		tf.hob_lbam = (new_sectors >> 32) & 0xff;
1285 		tf.hob_lbah = (new_sectors >> 40) & 0xff;
1286 	} else {
1287 		tf.command = ATA_CMD_SET_MAX;
1288 
1289 		tf.device |= (new_sectors >> 24) & 0xf;
1290 	}
1291 
1292 	tf.protocol = ATA_PROT_NODATA;
1293 	tf.device |= ATA_LBA;
1294 
1295 	tf.lbal = (new_sectors >> 0) & 0xff;
1296 	tf.lbam = (new_sectors >> 8) & 0xff;
1297 	tf.lbah = (new_sectors >> 16) & 0xff;
1298 
1299 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
1300 	if (err_mask) {
1301 		ata_dev_warn(dev,
1302 			     "failed to set max address (err_mask=0x%x)\n",
1303 			     err_mask);
1304 		if (err_mask == AC_ERR_DEV &&
1305 		    (tf.feature & (ATA_ABORTED | ATA_IDNF)))
1306 			return -EACCES;
1307 		return -EIO;
1308 	}
1309 
1310 	return 0;
1311 }
1312 
1313 /**
1314  *	ata_hpa_resize		-	Resize a device with an HPA set
1315  *	@dev: Device to resize
1316  *
1317  *	Read the size of an LBA28 or LBA48 disk with HPA features and resize
1318  *	it if required to the full size of the media. The caller must check
1319  *	the drive has the HPA feature set enabled.
1320  *
1321  *	RETURNS:
1322  *	0 on success, -errno on failure.
1323  */
1324 static int ata_hpa_resize(struct ata_device *dev)
1325 {
1326 	struct ata_eh_context *ehc = &dev->link->eh_context;
1327 	int print_info = ehc->i.flags & ATA_EHI_PRINTINFO;
1328 	bool unlock_hpa = ata_ignore_hpa || dev->flags & ATA_DFLAG_UNLOCK_HPA;
1329 	u64 sectors = ata_id_n_sectors(dev->id);
1330 	u64 native_sectors;
1331 	int rc;
1332 
1333 	/* do we need to do it? */
1334 	if ((dev->class != ATA_DEV_ATA && dev->class != ATA_DEV_ZAC) ||
1335 	    !ata_id_has_lba(dev->id) || !ata_id_hpa_enabled(dev->id) ||
1336 	    (dev->horkage & ATA_HORKAGE_BROKEN_HPA))
1337 		return 0;
1338 
1339 	/* read native max address */
1340 	rc = ata_read_native_max_address(dev, &native_sectors);
1341 	if (rc) {
1342 		/* If device aborted the command or HPA isn't going to
1343 		 * be unlocked, skip HPA resizing.
1344 		 */
1345 		if (rc == -EACCES || !unlock_hpa) {
1346 			ata_dev_warn(dev,
1347 				     "HPA support seems broken, skipping HPA handling\n");
1348 			dev->horkage |= ATA_HORKAGE_BROKEN_HPA;
1349 
1350 			/* we can continue if device aborted the command */
1351 			if (rc == -EACCES)
1352 				rc = 0;
1353 		}
1354 
1355 		return rc;
1356 	}
1357 	dev->n_native_sectors = native_sectors;
1358 
1359 	/* nothing to do? */
1360 	if (native_sectors <= sectors || !unlock_hpa) {
1361 		if (!print_info || native_sectors == sectors)
1362 			return 0;
1363 
1364 		if (native_sectors > sectors)
1365 			ata_dev_info(dev,
1366 				"HPA detected: current %llu, native %llu\n",
1367 				(unsigned long long)sectors,
1368 				(unsigned long long)native_sectors);
1369 		else if (native_sectors < sectors)
1370 			ata_dev_warn(dev,
1371 				"native sectors (%llu) is smaller than sectors (%llu)\n",
1372 				(unsigned long long)native_sectors,
1373 				(unsigned long long)sectors);
1374 		return 0;
1375 	}
1376 
1377 	/* let's unlock HPA */
1378 	rc = ata_set_max_sectors(dev, native_sectors);
1379 	if (rc == -EACCES) {
1380 		/* if device aborted the command, skip HPA resizing */
1381 		ata_dev_warn(dev,
1382 			     "device aborted resize (%llu -> %llu), skipping HPA handling\n",
1383 			     (unsigned long long)sectors,
1384 			     (unsigned long long)native_sectors);
1385 		dev->horkage |= ATA_HORKAGE_BROKEN_HPA;
1386 		return 0;
1387 	} else if (rc)
1388 		return rc;
1389 
1390 	/* re-read IDENTIFY data */
1391 	rc = ata_dev_reread_id(dev, 0);
1392 	if (rc) {
1393 		ata_dev_err(dev,
1394 			    "failed to re-read IDENTIFY data after HPA resizing\n");
1395 		return rc;
1396 	}
1397 
1398 	if (print_info) {
1399 		u64 new_sectors = ata_id_n_sectors(dev->id);
1400 		ata_dev_info(dev,
1401 			"HPA unlocked: %llu -> %llu, native %llu\n",
1402 			(unsigned long long)sectors,
1403 			(unsigned long long)new_sectors,
1404 			(unsigned long long)native_sectors);
1405 	}
1406 
1407 	return 0;
1408 }
1409 
1410 /**
1411  *	ata_dump_id - IDENTIFY DEVICE info debugging output
1412  *	@id: IDENTIFY DEVICE page to dump
1413  *
1414  *	Dump selected 16-bit words from the given IDENTIFY DEVICE
1415  *	page.
1416  *
1417  *	LOCKING:
1418  *	caller.
1419  */
1420 
1421 static inline void ata_dump_id(const u16 *id)
1422 {
1423 	DPRINTK("49==0x%04x  "
1424 		"53==0x%04x  "
1425 		"63==0x%04x  "
1426 		"64==0x%04x  "
1427 		"75==0x%04x  \n",
1428 		id[49],
1429 		id[53],
1430 		id[63],
1431 		id[64],
1432 		id[75]);
1433 	DPRINTK("80==0x%04x  "
1434 		"81==0x%04x  "
1435 		"82==0x%04x  "
1436 		"83==0x%04x  "
1437 		"84==0x%04x  \n",
1438 		id[80],
1439 		id[81],
1440 		id[82],
1441 		id[83],
1442 		id[84]);
1443 	DPRINTK("88==0x%04x  "
1444 		"93==0x%04x\n",
1445 		id[88],
1446 		id[93]);
1447 }
1448 
1449 /**
1450  *	ata_id_xfermask - Compute xfermask from the given IDENTIFY data
1451  *	@id: IDENTIFY data to compute xfer mask from
1452  *
1453  *	Compute the xfermask for this device. This is not as trivial
1454  *	as it seems if we must consider early devices correctly.
1455  *
1456  *	FIXME: pre IDE drive timing (do we care ?).
1457  *
1458  *	LOCKING:
1459  *	None.
1460  *
1461  *	RETURNS:
1462  *	Computed xfermask
1463  */
1464 unsigned long ata_id_xfermask(const u16 *id)
1465 {
1466 	unsigned long pio_mask, mwdma_mask, udma_mask;
1467 
1468 	/* Usual case. Word 53 indicates word 64 is valid */
1469 	if (id[ATA_ID_FIELD_VALID] & (1 << 1)) {
1470 		pio_mask = id[ATA_ID_PIO_MODES] & 0x03;
1471 		pio_mask <<= 3;
1472 		pio_mask |= 0x7;
1473 	} else {
1474 		/* If word 64 isn't valid then Word 51 high byte holds
1475 		 * the PIO timing number for the maximum. Turn it into
1476 		 * a mask.
1477 		 */
1478 		u8 mode = (id[ATA_ID_OLD_PIO_MODES] >> 8) & 0xFF;
1479 		if (mode < 5)	/* Valid PIO range */
1480 			pio_mask = (2 << mode) - 1;
1481 		else
1482 			pio_mask = 1;
1483 
1484 		/* But wait.. there's more. Design your standards by
1485 		 * committee and you too can get a free iordy field to
1486 		 * process. However its the speeds not the modes that
1487 		 * are supported... Note drivers using the timing API
1488 		 * will get this right anyway
1489 		 */
1490 	}
1491 
1492 	mwdma_mask = id[ATA_ID_MWDMA_MODES] & 0x07;
1493 
1494 	if (ata_id_is_cfa(id)) {
1495 		/*
1496 		 *	Process compact flash extended modes
1497 		 */
1498 		int pio = (id[ATA_ID_CFA_MODES] >> 0) & 0x7;
1499 		int dma = (id[ATA_ID_CFA_MODES] >> 3) & 0x7;
1500 
1501 		if (pio)
1502 			pio_mask |= (1 << 5);
1503 		if (pio > 1)
1504 			pio_mask |= (1 << 6);
1505 		if (dma)
1506 			mwdma_mask |= (1 << 3);
1507 		if (dma > 1)
1508 			mwdma_mask |= (1 << 4);
1509 	}
1510 
1511 	udma_mask = 0;
1512 	if (id[ATA_ID_FIELD_VALID] & (1 << 2))
1513 		udma_mask = id[ATA_ID_UDMA_MODES] & 0xff;
1514 
1515 	return ata_pack_xfermask(pio_mask, mwdma_mask, udma_mask);
1516 }
1517 
1518 static void ata_qc_complete_internal(struct ata_queued_cmd *qc)
1519 {
1520 	struct completion *waiting = qc->private_data;
1521 
1522 	complete(waiting);
1523 }
1524 
1525 /**
1526  *	ata_exec_internal_sg - execute libata internal command
1527  *	@dev: Device to which the command is sent
1528  *	@tf: Taskfile registers for the command and the result
1529  *	@cdb: CDB for packet command
1530  *	@dma_dir: Data transfer direction of the command
1531  *	@sgl: sg list for the data buffer of the command
1532  *	@n_elem: Number of sg entries
1533  *	@timeout: Timeout in msecs (0 for default)
1534  *
1535  *	Executes libata internal command with timeout.  @tf contains
1536  *	command on entry and result on return.  Timeout and error
1537  *	conditions are reported via return value.  No recovery action
1538  *	is taken after a command times out.  It's caller's duty to
1539  *	clean up after timeout.
1540  *
1541  *	LOCKING:
1542  *	None.  Should be called with kernel context, might sleep.
1543  *
1544  *	RETURNS:
1545  *	Zero on success, AC_ERR_* mask on failure
1546  */
1547 unsigned ata_exec_internal_sg(struct ata_device *dev,
1548 			      struct ata_taskfile *tf, const u8 *cdb,
1549 			      int dma_dir, struct scatterlist *sgl,
1550 			      unsigned int n_elem, unsigned long timeout)
1551 {
1552 	struct ata_link *link = dev->link;
1553 	struct ata_port *ap = link->ap;
1554 	u8 command = tf->command;
1555 	int auto_timeout = 0;
1556 	struct ata_queued_cmd *qc;
1557 	unsigned int preempted_tag;
1558 	u32 preempted_sactive;
1559 	u64 preempted_qc_active;
1560 	int preempted_nr_active_links;
1561 	DECLARE_COMPLETION_ONSTACK(wait);
1562 	unsigned long flags;
1563 	unsigned int err_mask;
1564 	int rc;
1565 
1566 	spin_lock_irqsave(ap->lock, flags);
1567 
1568 	/* no internal command while frozen */
1569 	if (ap->pflags & ATA_PFLAG_FROZEN) {
1570 		spin_unlock_irqrestore(ap->lock, flags);
1571 		return AC_ERR_SYSTEM;
1572 	}
1573 
1574 	/* initialize internal qc */
1575 	qc = __ata_qc_from_tag(ap, ATA_TAG_INTERNAL);
1576 
1577 	qc->tag = ATA_TAG_INTERNAL;
1578 	qc->hw_tag = 0;
1579 	qc->scsicmd = NULL;
1580 	qc->ap = ap;
1581 	qc->dev = dev;
1582 	ata_qc_reinit(qc);
1583 
1584 	preempted_tag = link->active_tag;
1585 	preempted_sactive = link->sactive;
1586 	preempted_qc_active = ap->qc_active;
1587 	preempted_nr_active_links = ap->nr_active_links;
1588 	link->active_tag = ATA_TAG_POISON;
1589 	link->sactive = 0;
1590 	ap->qc_active = 0;
1591 	ap->nr_active_links = 0;
1592 
1593 	/* prepare & issue qc */
1594 	qc->tf = *tf;
1595 	if (cdb)
1596 		memcpy(qc->cdb, cdb, ATAPI_CDB_LEN);
1597 
1598 	/* some SATA bridges need us to indicate data xfer direction */
1599 	if (tf->protocol == ATAPI_PROT_DMA && (dev->flags & ATA_DFLAG_DMADIR) &&
1600 	    dma_dir == DMA_FROM_DEVICE)
1601 		qc->tf.feature |= ATAPI_DMADIR;
1602 
1603 	qc->flags |= ATA_QCFLAG_RESULT_TF;
1604 	qc->dma_dir = dma_dir;
1605 	if (dma_dir != DMA_NONE) {
1606 		unsigned int i, buflen = 0;
1607 		struct scatterlist *sg;
1608 
1609 		for_each_sg(sgl, sg, n_elem, i)
1610 			buflen += sg->length;
1611 
1612 		ata_sg_init(qc, sgl, n_elem);
1613 		qc->nbytes = buflen;
1614 	}
1615 
1616 	qc->private_data = &wait;
1617 	qc->complete_fn = ata_qc_complete_internal;
1618 
1619 	ata_qc_issue(qc);
1620 
1621 	spin_unlock_irqrestore(ap->lock, flags);
1622 
1623 	if (!timeout) {
1624 		if (ata_probe_timeout)
1625 			timeout = ata_probe_timeout * 1000;
1626 		else {
1627 			timeout = ata_internal_cmd_timeout(dev, command);
1628 			auto_timeout = 1;
1629 		}
1630 	}
1631 
1632 	if (ap->ops->error_handler)
1633 		ata_eh_release(ap);
1634 
1635 	rc = wait_for_completion_timeout(&wait, msecs_to_jiffies(timeout));
1636 
1637 	if (ap->ops->error_handler)
1638 		ata_eh_acquire(ap);
1639 
1640 	ata_sff_flush_pio_task(ap);
1641 
1642 	if (!rc) {
1643 		spin_lock_irqsave(ap->lock, flags);
1644 
1645 		/* We're racing with irq here.  If we lose, the
1646 		 * following test prevents us from completing the qc
1647 		 * twice.  If we win, the port is frozen and will be
1648 		 * cleaned up by ->post_internal_cmd().
1649 		 */
1650 		if (qc->flags & ATA_QCFLAG_ACTIVE) {
1651 			qc->err_mask |= AC_ERR_TIMEOUT;
1652 
1653 			if (ap->ops->error_handler)
1654 				ata_port_freeze(ap);
1655 			else
1656 				ata_qc_complete(qc);
1657 
1658 			if (ata_msg_warn(ap))
1659 				ata_dev_warn(dev, "qc timeout (cmd 0x%x)\n",
1660 					     command);
1661 		}
1662 
1663 		spin_unlock_irqrestore(ap->lock, flags);
1664 	}
1665 
1666 	/* do post_internal_cmd */
1667 	if (ap->ops->post_internal_cmd)
1668 		ap->ops->post_internal_cmd(qc);
1669 
1670 	/* perform minimal error analysis */
1671 	if (qc->flags & ATA_QCFLAG_FAILED) {
1672 		if (qc->result_tf.command & (ATA_ERR | ATA_DF))
1673 			qc->err_mask |= AC_ERR_DEV;
1674 
1675 		if (!qc->err_mask)
1676 			qc->err_mask |= AC_ERR_OTHER;
1677 
1678 		if (qc->err_mask & ~AC_ERR_OTHER)
1679 			qc->err_mask &= ~AC_ERR_OTHER;
1680 	} else if (qc->tf.command == ATA_CMD_REQ_SENSE_DATA) {
1681 		qc->result_tf.command |= ATA_SENSE;
1682 	}
1683 
1684 	/* finish up */
1685 	spin_lock_irqsave(ap->lock, flags);
1686 
1687 	*tf = qc->result_tf;
1688 	err_mask = qc->err_mask;
1689 
1690 	ata_qc_free(qc);
1691 	link->active_tag = preempted_tag;
1692 	link->sactive = preempted_sactive;
1693 	ap->qc_active = preempted_qc_active;
1694 	ap->nr_active_links = preempted_nr_active_links;
1695 
1696 	spin_unlock_irqrestore(ap->lock, flags);
1697 
1698 	if ((err_mask & AC_ERR_TIMEOUT) && auto_timeout)
1699 		ata_internal_cmd_timed_out(dev, command);
1700 
1701 	return err_mask;
1702 }
1703 
1704 /**
1705  *	ata_exec_internal - execute libata internal command
1706  *	@dev: Device to which the command is sent
1707  *	@tf: Taskfile registers for the command and the result
1708  *	@cdb: CDB for packet command
1709  *	@dma_dir: Data transfer direction of the command
1710  *	@buf: Data buffer of the command
1711  *	@buflen: Length of data buffer
1712  *	@timeout: Timeout in msecs (0 for default)
1713  *
1714  *	Wrapper around ata_exec_internal_sg() which takes simple
1715  *	buffer instead of sg list.
1716  *
1717  *	LOCKING:
1718  *	None.  Should be called with kernel context, might sleep.
1719  *
1720  *	RETURNS:
1721  *	Zero on success, AC_ERR_* mask on failure
1722  */
1723 unsigned ata_exec_internal(struct ata_device *dev,
1724 			   struct ata_taskfile *tf, const u8 *cdb,
1725 			   int dma_dir, void *buf, unsigned int buflen,
1726 			   unsigned long timeout)
1727 {
1728 	struct scatterlist *psg = NULL, sg;
1729 	unsigned int n_elem = 0;
1730 
1731 	if (dma_dir != DMA_NONE) {
1732 		WARN_ON(!buf);
1733 		sg_init_one(&sg, buf, buflen);
1734 		psg = &sg;
1735 		n_elem++;
1736 	}
1737 
1738 	return ata_exec_internal_sg(dev, tf, cdb, dma_dir, psg, n_elem,
1739 				    timeout);
1740 }
1741 
1742 /**
1743  *	ata_pio_need_iordy	-	check if iordy needed
1744  *	@adev: ATA device
1745  *
1746  *	Check if the current speed of the device requires IORDY. Used
1747  *	by various controllers for chip configuration.
1748  */
1749 unsigned int ata_pio_need_iordy(const struct ata_device *adev)
1750 {
1751 	/* Don't set IORDY if we're preparing for reset.  IORDY may
1752 	 * lead to controller lock up on certain controllers if the
1753 	 * port is not occupied.  See bko#11703 for details.
1754 	 */
1755 	if (adev->link->ap->pflags & ATA_PFLAG_RESETTING)
1756 		return 0;
1757 	/* Controller doesn't support IORDY.  Probably a pointless
1758 	 * check as the caller should know this.
1759 	 */
1760 	if (adev->link->ap->flags & ATA_FLAG_NO_IORDY)
1761 		return 0;
1762 	/* CF spec. r4.1 Table 22 says no iordy on PIO5 and PIO6.  */
1763 	if (ata_id_is_cfa(adev->id)
1764 	    && (adev->pio_mode == XFER_PIO_5 || adev->pio_mode == XFER_PIO_6))
1765 		return 0;
1766 	/* PIO3 and higher it is mandatory */
1767 	if (adev->pio_mode > XFER_PIO_2)
1768 		return 1;
1769 	/* We turn it on when possible */
1770 	if (ata_id_has_iordy(adev->id))
1771 		return 1;
1772 	return 0;
1773 }
1774 
1775 /**
1776  *	ata_pio_mask_no_iordy	-	Return the non IORDY mask
1777  *	@adev: ATA device
1778  *
1779  *	Compute the highest mode possible if we are not using iordy. Return
1780  *	-1 if no iordy mode is available.
1781  */
1782 static u32 ata_pio_mask_no_iordy(const struct ata_device *adev)
1783 {
1784 	/* If we have no drive specific rule, then PIO 2 is non IORDY */
1785 	if (adev->id[ATA_ID_FIELD_VALID] & 2) {	/* EIDE */
1786 		u16 pio = adev->id[ATA_ID_EIDE_PIO];
1787 		/* Is the speed faster than the drive allows non IORDY ? */
1788 		if (pio) {
1789 			/* This is cycle times not frequency - watch the logic! */
1790 			if (pio > 240)	/* PIO2 is 240nS per cycle */
1791 				return 3 << ATA_SHIFT_PIO;
1792 			return 7 << ATA_SHIFT_PIO;
1793 		}
1794 	}
1795 	return 3 << ATA_SHIFT_PIO;
1796 }
1797 
1798 /**
1799  *	ata_do_dev_read_id		-	default ID read method
1800  *	@dev: device
1801  *	@tf: proposed taskfile
1802  *	@id: data buffer
1803  *
1804  *	Issue the identify taskfile and hand back the buffer containing
1805  *	identify data. For some RAID controllers and for pre ATA devices
1806  *	this function is wrapped or replaced by the driver
1807  */
1808 unsigned int ata_do_dev_read_id(struct ata_device *dev,
1809 					struct ata_taskfile *tf, u16 *id)
1810 {
1811 	return ata_exec_internal(dev, tf, NULL, DMA_FROM_DEVICE,
1812 				     id, sizeof(id[0]) * ATA_ID_WORDS, 0);
1813 }
1814 
1815 /**
1816  *	ata_dev_read_id - Read ID data from the specified device
1817  *	@dev: target device
1818  *	@p_class: pointer to class of the target device (may be changed)
1819  *	@flags: ATA_READID_* flags
1820  *	@id: buffer to read IDENTIFY data into
1821  *
1822  *	Read ID data from the specified device.  ATA_CMD_ID_ATA is
1823  *	performed on ATA devices and ATA_CMD_ID_ATAPI on ATAPI
1824  *	devices.  This function also issues ATA_CMD_INIT_DEV_PARAMS
1825  *	for pre-ATA4 drives.
1826  *
1827  *	FIXME: ATA_CMD_ID_ATA is optional for early drives and right
1828  *	now we abort if we hit that case.
1829  *
1830  *	LOCKING:
1831  *	Kernel thread context (may sleep)
1832  *
1833  *	RETURNS:
1834  *	0 on success, -errno otherwise.
1835  */
1836 int ata_dev_read_id(struct ata_device *dev, unsigned int *p_class,
1837 		    unsigned int flags, u16 *id)
1838 {
1839 	struct ata_port *ap = dev->link->ap;
1840 	unsigned int class = *p_class;
1841 	struct ata_taskfile tf;
1842 	unsigned int err_mask = 0;
1843 	const char *reason;
1844 	bool is_semb = class == ATA_DEV_SEMB;
1845 	int may_fallback = 1, tried_spinup = 0;
1846 	int rc;
1847 
1848 	if (ata_msg_ctl(ap))
1849 		ata_dev_dbg(dev, "%s: ENTER\n", __func__);
1850 
1851 retry:
1852 	ata_tf_init(dev, &tf);
1853 
1854 	switch (class) {
1855 	case ATA_DEV_SEMB:
1856 		class = ATA_DEV_ATA;	/* some hard drives report SEMB sig */
1857 		/* fall through */
1858 	case ATA_DEV_ATA:
1859 	case ATA_DEV_ZAC:
1860 		tf.command = ATA_CMD_ID_ATA;
1861 		break;
1862 	case ATA_DEV_ATAPI:
1863 		tf.command = ATA_CMD_ID_ATAPI;
1864 		break;
1865 	default:
1866 		rc = -ENODEV;
1867 		reason = "unsupported class";
1868 		goto err_out;
1869 	}
1870 
1871 	tf.protocol = ATA_PROT_PIO;
1872 
1873 	/* Some devices choke if TF registers contain garbage.  Make
1874 	 * sure those are properly initialized.
1875 	 */
1876 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1877 
1878 	/* Device presence detection is unreliable on some
1879 	 * controllers.  Always poll IDENTIFY if available.
1880 	 */
1881 	tf.flags |= ATA_TFLAG_POLLING;
1882 
1883 	if (ap->ops->read_id)
1884 		err_mask = ap->ops->read_id(dev, &tf, id);
1885 	else
1886 		err_mask = ata_do_dev_read_id(dev, &tf, id);
1887 
1888 	if (err_mask) {
1889 		if (err_mask & AC_ERR_NODEV_HINT) {
1890 			ata_dev_dbg(dev, "NODEV after polling detection\n");
1891 			return -ENOENT;
1892 		}
1893 
1894 		if (is_semb) {
1895 			ata_dev_info(dev,
1896 		     "IDENTIFY failed on device w/ SEMB sig, disabled\n");
1897 			/* SEMB is not supported yet */
1898 			*p_class = ATA_DEV_SEMB_UNSUP;
1899 			return 0;
1900 		}
1901 
1902 		if ((err_mask == AC_ERR_DEV) && (tf.feature & ATA_ABORTED)) {
1903 			/* Device or controller might have reported
1904 			 * the wrong device class.  Give a shot at the
1905 			 * other IDENTIFY if the current one is
1906 			 * aborted by the device.
1907 			 */
1908 			if (may_fallback) {
1909 				may_fallback = 0;
1910 
1911 				if (class == ATA_DEV_ATA)
1912 					class = ATA_DEV_ATAPI;
1913 				else
1914 					class = ATA_DEV_ATA;
1915 				goto retry;
1916 			}
1917 
1918 			/* Control reaches here iff the device aborted
1919 			 * both flavors of IDENTIFYs which happens
1920 			 * sometimes with phantom devices.
1921 			 */
1922 			ata_dev_dbg(dev,
1923 				    "both IDENTIFYs aborted, assuming NODEV\n");
1924 			return -ENOENT;
1925 		}
1926 
1927 		rc = -EIO;
1928 		reason = "I/O error";
1929 		goto err_out;
1930 	}
1931 
1932 	if (dev->horkage & ATA_HORKAGE_DUMP_ID) {
1933 		ata_dev_dbg(dev, "dumping IDENTIFY data, "
1934 			    "class=%d may_fallback=%d tried_spinup=%d\n",
1935 			    class, may_fallback, tried_spinup);
1936 		print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET,
1937 			       16, 2, id, ATA_ID_WORDS * sizeof(*id), true);
1938 	}
1939 
1940 	/* Falling back doesn't make sense if ID data was read
1941 	 * successfully at least once.
1942 	 */
1943 	may_fallback = 0;
1944 
1945 	swap_buf_le16(id, ATA_ID_WORDS);
1946 
1947 	/* sanity check */
1948 	rc = -EINVAL;
1949 	reason = "device reports invalid type";
1950 
1951 	if (class == ATA_DEV_ATA || class == ATA_DEV_ZAC) {
1952 		if (!ata_id_is_ata(id) && !ata_id_is_cfa(id))
1953 			goto err_out;
1954 		if (ap->host->flags & ATA_HOST_IGNORE_ATA &&
1955 							ata_id_is_ata(id)) {
1956 			ata_dev_dbg(dev,
1957 				"host indicates ignore ATA devices, ignored\n");
1958 			return -ENOENT;
1959 		}
1960 	} else {
1961 		if (ata_id_is_ata(id))
1962 			goto err_out;
1963 	}
1964 
1965 	if (!tried_spinup && (id[2] == 0x37c8 || id[2] == 0x738c)) {
1966 		tried_spinup = 1;
1967 		/*
1968 		 * Drive powered-up in standby mode, and requires a specific
1969 		 * SET_FEATURES spin-up subcommand before it will accept
1970 		 * anything other than the original IDENTIFY command.
1971 		 */
1972 		err_mask = ata_dev_set_feature(dev, SETFEATURES_SPINUP, 0);
1973 		if (err_mask && id[2] != 0x738c) {
1974 			rc = -EIO;
1975 			reason = "SPINUP failed";
1976 			goto err_out;
1977 		}
1978 		/*
1979 		 * If the drive initially returned incomplete IDENTIFY info,
1980 		 * we now must reissue the IDENTIFY command.
1981 		 */
1982 		if (id[2] == 0x37c8)
1983 			goto retry;
1984 	}
1985 
1986 	if ((flags & ATA_READID_POSTRESET) &&
1987 	    (class == ATA_DEV_ATA || class == ATA_DEV_ZAC)) {
1988 		/*
1989 		 * The exact sequence expected by certain pre-ATA4 drives is:
1990 		 * SRST RESET
1991 		 * IDENTIFY (optional in early ATA)
1992 		 * INITIALIZE DEVICE PARAMETERS (later IDE and ATA)
1993 		 * anything else..
1994 		 * Some drives were very specific about that exact sequence.
1995 		 *
1996 		 * Note that ATA4 says lba is mandatory so the second check
1997 		 * should never trigger.
1998 		 */
1999 		if (ata_id_major_version(id) < 4 || !ata_id_has_lba(id)) {
2000 			err_mask = ata_dev_init_params(dev, id[3], id[6]);
2001 			if (err_mask) {
2002 				rc = -EIO;
2003 				reason = "INIT_DEV_PARAMS failed";
2004 				goto err_out;
2005 			}
2006 
2007 			/* current CHS translation info (id[53-58]) might be
2008 			 * changed. reread the identify device info.
2009 			 */
2010 			flags &= ~ATA_READID_POSTRESET;
2011 			goto retry;
2012 		}
2013 	}
2014 
2015 	*p_class = class;
2016 
2017 	return 0;
2018 
2019  err_out:
2020 	if (ata_msg_warn(ap))
2021 		ata_dev_warn(dev, "failed to IDENTIFY (%s, err_mask=0x%x)\n",
2022 			     reason, err_mask);
2023 	return rc;
2024 }
2025 
2026 /**
2027  *	ata_read_log_page - read a specific log page
2028  *	@dev: target device
2029  *	@log: log to read
2030  *	@page: page to read
2031  *	@buf: buffer to store read page
2032  *	@sectors: number of sectors to read
2033  *
2034  *	Read log page using READ_LOG_EXT command.
2035  *
2036  *	LOCKING:
2037  *	Kernel thread context (may sleep).
2038  *
2039  *	RETURNS:
2040  *	0 on success, AC_ERR_* mask otherwise.
2041  */
2042 unsigned int ata_read_log_page(struct ata_device *dev, u8 log,
2043 			       u8 page, void *buf, unsigned int sectors)
2044 {
2045 	unsigned long ap_flags = dev->link->ap->flags;
2046 	struct ata_taskfile tf;
2047 	unsigned int err_mask;
2048 	bool dma = false;
2049 
2050 	DPRINTK("read log page - log 0x%x, page 0x%x\n", log, page);
2051 
2052 	/*
2053 	 * Return error without actually issuing the command on controllers
2054 	 * which e.g. lockup on a read log page.
2055 	 */
2056 	if (ap_flags & ATA_FLAG_NO_LOG_PAGE)
2057 		return AC_ERR_DEV;
2058 
2059 retry:
2060 	ata_tf_init(dev, &tf);
2061 	if (dev->dma_mode && ata_id_has_read_log_dma_ext(dev->id) &&
2062 	    !(dev->horkage & ATA_HORKAGE_NO_DMA_LOG)) {
2063 		tf.command = ATA_CMD_READ_LOG_DMA_EXT;
2064 		tf.protocol = ATA_PROT_DMA;
2065 		dma = true;
2066 	} else {
2067 		tf.command = ATA_CMD_READ_LOG_EXT;
2068 		tf.protocol = ATA_PROT_PIO;
2069 		dma = false;
2070 	}
2071 	tf.lbal = log;
2072 	tf.lbam = page;
2073 	tf.nsect = sectors;
2074 	tf.hob_nsect = sectors >> 8;
2075 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_LBA48 | ATA_TFLAG_DEVICE;
2076 
2077 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_FROM_DEVICE,
2078 				     buf, sectors * ATA_SECT_SIZE, 0);
2079 
2080 	if (err_mask && dma) {
2081 		dev->horkage |= ATA_HORKAGE_NO_DMA_LOG;
2082 		ata_dev_warn(dev, "READ LOG DMA EXT failed, trying PIO\n");
2083 		goto retry;
2084 	}
2085 
2086 	DPRINTK("EXIT, err_mask=%x\n", err_mask);
2087 	return err_mask;
2088 }
2089 
2090 static bool ata_log_supported(struct ata_device *dev, u8 log)
2091 {
2092 	struct ata_port *ap = dev->link->ap;
2093 
2094 	if (ata_read_log_page(dev, ATA_LOG_DIRECTORY, 0, ap->sector_buf, 1))
2095 		return false;
2096 	return get_unaligned_le16(&ap->sector_buf[log * 2]) ? true : false;
2097 }
2098 
2099 static bool ata_identify_page_supported(struct ata_device *dev, u8 page)
2100 {
2101 	struct ata_port *ap = dev->link->ap;
2102 	unsigned int err, i;
2103 
2104 	if (!ata_log_supported(dev, ATA_LOG_IDENTIFY_DEVICE)) {
2105 		ata_dev_warn(dev, "ATA Identify Device Log not supported\n");
2106 		return false;
2107 	}
2108 
2109 	/*
2110 	 * Read IDENTIFY DEVICE data log, page 0, to figure out if the page is
2111 	 * supported.
2112 	 */
2113 	err = ata_read_log_page(dev, ATA_LOG_IDENTIFY_DEVICE, 0, ap->sector_buf,
2114 				1);
2115 	if (err) {
2116 		ata_dev_info(dev,
2117 			     "failed to get Device Identify Log Emask 0x%x\n",
2118 			     err);
2119 		return false;
2120 	}
2121 
2122 	for (i = 0; i < ap->sector_buf[8]; i++) {
2123 		if (ap->sector_buf[9 + i] == page)
2124 			return true;
2125 	}
2126 
2127 	return false;
2128 }
2129 
2130 static int ata_do_link_spd_horkage(struct ata_device *dev)
2131 {
2132 	struct ata_link *plink = ata_dev_phys_link(dev);
2133 	u32 target, target_limit;
2134 
2135 	if (!sata_scr_valid(plink))
2136 		return 0;
2137 
2138 	if (dev->horkage & ATA_HORKAGE_1_5_GBPS)
2139 		target = 1;
2140 	else
2141 		return 0;
2142 
2143 	target_limit = (1 << target) - 1;
2144 
2145 	/* if already on stricter limit, no need to push further */
2146 	if (plink->sata_spd_limit <= target_limit)
2147 		return 0;
2148 
2149 	plink->sata_spd_limit = target_limit;
2150 
2151 	/* Request another EH round by returning -EAGAIN if link is
2152 	 * going faster than the target speed.  Forward progress is
2153 	 * guaranteed by setting sata_spd_limit to target_limit above.
2154 	 */
2155 	if (plink->sata_spd > target) {
2156 		ata_dev_info(dev, "applying link speed limit horkage to %s\n",
2157 			     sata_spd_string(target));
2158 		return -EAGAIN;
2159 	}
2160 	return 0;
2161 }
2162 
2163 static inline u8 ata_dev_knobble(struct ata_device *dev)
2164 {
2165 	struct ata_port *ap = dev->link->ap;
2166 
2167 	if (ata_dev_blacklisted(dev) & ATA_HORKAGE_BRIDGE_OK)
2168 		return 0;
2169 
2170 	return ((ap->cbl == ATA_CBL_SATA) && (!ata_id_is_sata(dev->id)));
2171 }
2172 
2173 static void ata_dev_config_ncq_send_recv(struct ata_device *dev)
2174 {
2175 	struct ata_port *ap = dev->link->ap;
2176 	unsigned int err_mask;
2177 
2178 	if (!ata_log_supported(dev, ATA_LOG_NCQ_SEND_RECV)) {
2179 		ata_dev_warn(dev, "NCQ Send/Recv Log not supported\n");
2180 		return;
2181 	}
2182 	err_mask = ata_read_log_page(dev, ATA_LOG_NCQ_SEND_RECV,
2183 				     0, ap->sector_buf, 1);
2184 	if (err_mask) {
2185 		ata_dev_dbg(dev,
2186 			    "failed to get NCQ Send/Recv Log Emask 0x%x\n",
2187 			    err_mask);
2188 	} else {
2189 		u8 *cmds = dev->ncq_send_recv_cmds;
2190 
2191 		dev->flags |= ATA_DFLAG_NCQ_SEND_RECV;
2192 		memcpy(cmds, ap->sector_buf, ATA_LOG_NCQ_SEND_RECV_SIZE);
2193 
2194 		if (dev->horkage & ATA_HORKAGE_NO_NCQ_TRIM) {
2195 			ata_dev_dbg(dev, "disabling queued TRIM support\n");
2196 			cmds[ATA_LOG_NCQ_SEND_RECV_DSM_OFFSET] &=
2197 				~ATA_LOG_NCQ_SEND_RECV_DSM_TRIM;
2198 		}
2199 	}
2200 }
2201 
2202 static void ata_dev_config_ncq_non_data(struct ata_device *dev)
2203 {
2204 	struct ata_port *ap = dev->link->ap;
2205 	unsigned int err_mask;
2206 
2207 	if (!ata_log_supported(dev, ATA_LOG_NCQ_NON_DATA)) {
2208 		ata_dev_warn(dev,
2209 			     "NCQ Send/Recv Log not supported\n");
2210 		return;
2211 	}
2212 	err_mask = ata_read_log_page(dev, ATA_LOG_NCQ_NON_DATA,
2213 				     0, ap->sector_buf, 1);
2214 	if (err_mask) {
2215 		ata_dev_dbg(dev,
2216 			    "failed to get NCQ Non-Data Log Emask 0x%x\n",
2217 			    err_mask);
2218 	} else {
2219 		u8 *cmds = dev->ncq_non_data_cmds;
2220 
2221 		memcpy(cmds, ap->sector_buf, ATA_LOG_NCQ_NON_DATA_SIZE);
2222 	}
2223 }
2224 
2225 static void ata_dev_config_ncq_prio(struct ata_device *dev)
2226 {
2227 	struct ata_port *ap = dev->link->ap;
2228 	unsigned int err_mask;
2229 
2230 	if (!(dev->flags & ATA_DFLAG_NCQ_PRIO_ENABLE)) {
2231 		dev->flags &= ~ATA_DFLAG_NCQ_PRIO;
2232 		return;
2233 	}
2234 
2235 	err_mask = ata_read_log_page(dev,
2236 				     ATA_LOG_IDENTIFY_DEVICE,
2237 				     ATA_LOG_SATA_SETTINGS,
2238 				     ap->sector_buf,
2239 				     1);
2240 	if (err_mask) {
2241 		ata_dev_dbg(dev,
2242 			    "failed to get Identify Device data, Emask 0x%x\n",
2243 			    err_mask);
2244 		return;
2245 	}
2246 
2247 	if (ap->sector_buf[ATA_LOG_NCQ_PRIO_OFFSET] & BIT(3)) {
2248 		dev->flags |= ATA_DFLAG_NCQ_PRIO;
2249 	} else {
2250 		dev->flags &= ~ATA_DFLAG_NCQ_PRIO;
2251 		ata_dev_dbg(dev, "SATA page does not support priority\n");
2252 	}
2253 
2254 }
2255 
2256 static int ata_dev_config_ncq(struct ata_device *dev,
2257 			       char *desc, size_t desc_sz)
2258 {
2259 	struct ata_port *ap = dev->link->ap;
2260 	int hdepth = 0, ddepth = ata_id_queue_depth(dev->id);
2261 	unsigned int err_mask;
2262 	char *aa_desc = "";
2263 
2264 	if (!ata_id_has_ncq(dev->id)) {
2265 		desc[0] = '\0';
2266 		return 0;
2267 	}
2268 	if (dev->horkage & ATA_HORKAGE_NONCQ) {
2269 		snprintf(desc, desc_sz, "NCQ (not used)");
2270 		return 0;
2271 	}
2272 	if (ap->flags & ATA_FLAG_NCQ) {
2273 		hdepth = min(ap->scsi_host->can_queue, ATA_MAX_QUEUE);
2274 		dev->flags |= ATA_DFLAG_NCQ;
2275 	}
2276 
2277 	if (!(dev->horkage & ATA_HORKAGE_BROKEN_FPDMA_AA) &&
2278 		(ap->flags & ATA_FLAG_FPDMA_AA) &&
2279 		ata_id_has_fpdma_aa(dev->id)) {
2280 		err_mask = ata_dev_set_feature(dev, SETFEATURES_SATA_ENABLE,
2281 			SATA_FPDMA_AA);
2282 		if (err_mask) {
2283 			ata_dev_err(dev,
2284 				    "failed to enable AA (error_mask=0x%x)\n",
2285 				    err_mask);
2286 			if (err_mask != AC_ERR_DEV) {
2287 				dev->horkage |= ATA_HORKAGE_BROKEN_FPDMA_AA;
2288 				return -EIO;
2289 			}
2290 		} else
2291 			aa_desc = ", AA";
2292 	}
2293 
2294 	if (hdepth >= ddepth)
2295 		snprintf(desc, desc_sz, "NCQ (depth %d)%s", ddepth, aa_desc);
2296 	else
2297 		snprintf(desc, desc_sz, "NCQ (depth %d/%d)%s", hdepth,
2298 			ddepth, aa_desc);
2299 
2300 	if ((ap->flags & ATA_FLAG_FPDMA_AUX)) {
2301 		if (ata_id_has_ncq_send_and_recv(dev->id))
2302 			ata_dev_config_ncq_send_recv(dev);
2303 		if (ata_id_has_ncq_non_data(dev->id))
2304 			ata_dev_config_ncq_non_data(dev);
2305 		if (ata_id_has_ncq_prio(dev->id))
2306 			ata_dev_config_ncq_prio(dev);
2307 	}
2308 
2309 	return 0;
2310 }
2311 
2312 static void ata_dev_config_sense_reporting(struct ata_device *dev)
2313 {
2314 	unsigned int err_mask;
2315 
2316 	if (!ata_id_has_sense_reporting(dev->id))
2317 		return;
2318 
2319 	if (ata_id_sense_reporting_enabled(dev->id))
2320 		return;
2321 
2322 	err_mask = ata_dev_set_feature(dev, SETFEATURE_SENSE_DATA, 0x1);
2323 	if (err_mask) {
2324 		ata_dev_dbg(dev,
2325 			    "failed to enable Sense Data Reporting, Emask 0x%x\n",
2326 			    err_mask);
2327 	}
2328 }
2329 
2330 static void ata_dev_config_zac(struct ata_device *dev)
2331 {
2332 	struct ata_port *ap = dev->link->ap;
2333 	unsigned int err_mask;
2334 	u8 *identify_buf = ap->sector_buf;
2335 
2336 	dev->zac_zones_optimal_open = U32_MAX;
2337 	dev->zac_zones_optimal_nonseq = U32_MAX;
2338 	dev->zac_zones_max_open = U32_MAX;
2339 
2340 	/*
2341 	 * Always set the 'ZAC' flag for Host-managed devices.
2342 	 */
2343 	if (dev->class == ATA_DEV_ZAC)
2344 		dev->flags |= ATA_DFLAG_ZAC;
2345 	else if (ata_id_zoned_cap(dev->id) == 0x01)
2346 		/*
2347 		 * Check for host-aware devices.
2348 		 */
2349 		dev->flags |= ATA_DFLAG_ZAC;
2350 
2351 	if (!(dev->flags & ATA_DFLAG_ZAC))
2352 		return;
2353 
2354 	if (!ata_identify_page_supported(dev, ATA_LOG_ZONED_INFORMATION)) {
2355 		ata_dev_warn(dev,
2356 			     "ATA Zoned Information Log not supported\n");
2357 		return;
2358 	}
2359 
2360 	/*
2361 	 * Read IDENTIFY DEVICE data log, page 9 (Zoned-device information)
2362 	 */
2363 	err_mask = ata_read_log_page(dev, ATA_LOG_IDENTIFY_DEVICE,
2364 				     ATA_LOG_ZONED_INFORMATION,
2365 				     identify_buf, 1);
2366 	if (!err_mask) {
2367 		u64 zoned_cap, opt_open, opt_nonseq, max_open;
2368 
2369 		zoned_cap = get_unaligned_le64(&identify_buf[8]);
2370 		if ((zoned_cap >> 63))
2371 			dev->zac_zoned_cap = (zoned_cap & 1);
2372 		opt_open = get_unaligned_le64(&identify_buf[24]);
2373 		if ((opt_open >> 63))
2374 			dev->zac_zones_optimal_open = (u32)opt_open;
2375 		opt_nonseq = get_unaligned_le64(&identify_buf[32]);
2376 		if ((opt_nonseq >> 63))
2377 			dev->zac_zones_optimal_nonseq = (u32)opt_nonseq;
2378 		max_open = get_unaligned_le64(&identify_buf[40]);
2379 		if ((max_open >> 63))
2380 			dev->zac_zones_max_open = (u32)max_open;
2381 	}
2382 }
2383 
2384 static void ata_dev_config_trusted(struct ata_device *dev)
2385 {
2386 	struct ata_port *ap = dev->link->ap;
2387 	u64 trusted_cap;
2388 	unsigned int err;
2389 
2390 	if (!ata_id_has_trusted(dev->id))
2391 		return;
2392 
2393 	if (!ata_identify_page_supported(dev, ATA_LOG_SECURITY)) {
2394 		ata_dev_warn(dev,
2395 			     "Security Log not supported\n");
2396 		return;
2397 	}
2398 
2399 	err = ata_read_log_page(dev, ATA_LOG_IDENTIFY_DEVICE, ATA_LOG_SECURITY,
2400 			ap->sector_buf, 1);
2401 	if (err) {
2402 		ata_dev_dbg(dev,
2403 			    "failed to read Security Log, Emask 0x%x\n", err);
2404 		return;
2405 	}
2406 
2407 	trusted_cap = get_unaligned_le64(&ap->sector_buf[40]);
2408 	if (!(trusted_cap & (1ULL << 63))) {
2409 		ata_dev_dbg(dev,
2410 			    "Trusted Computing capability qword not valid!\n");
2411 		return;
2412 	}
2413 
2414 	if (trusted_cap & (1 << 0))
2415 		dev->flags |= ATA_DFLAG_TRUSTED;
2416 }
2417 
2418 /**
2419  *	ata_dev_configure - Configure the specified ATA/ATAPI device
2420  *	@dev: Target device to configure
2421  *
2422  *	Configure @dev according to @dev->id.  Generic and low-level
2423  *	driver specific fixups are also applied.
2424  *
2425  *	LOCKING:
2426  *	Kernel thread context (may sleep)
2427  *
2428  *	RETURNS:
2429  *	0 on success, -errno otherwise
2430  */
2431 int ata_dev_configure(struct ata_device *dev)
2432 {
2433 	struct ata_port *ap = dev->link->ap;
2434 	struct ata_eh_context *ehc = &dev->link->eh_context;
2435 	int print_info = ehc->i.flags & ATA_EHI_PRINTINFO;
2436 	const u16 *id = dev->id;
2437 	unsigned long xfer_mask;
2438 	unsigned int err_mask;
2439 	char revbuf[7];		/* XYZ-99\0 */
2440 	char fwrevbuf[ATA_ID_FW_REV_LEN+1];
2441 	char modelbuf[ATA_ID_PROD_LEN+1];
2442 	int rc;
2443 
2444 	if (!ata_dev_enabled(dev) && ata_msg_info(ap)) {
2445 		ata_dev_info(dev, "%s: ENTER/EXIT -- nodev\n", __func__);
2446 		return 0;
2447 	}
2448 
2449 	if (ata_msg_probe(ap))
2450 		ata_dev_dbg(dev, "%s: ENTER\n", __func__);
2451 
2452 	/* set horkage */
2453 	dev->horkage |= ata_dev_blacklisted(dev);
2454 	ata_force_horkage(dev);
2455 
2456 	if (dev->horkage & ATA_HORKAGE_DISABLE) {
2457 		ata_dev_info(dev, "unsupported device, disabling\n");
2458 		ata_dev_disable(dev);
2459 		return 0;
2460 	}
2461 
2462 	if ((!atapi_enabled || (ap->flags & ATA_FLAG_NO_ATAPI)) &&
2463 	    dev->class == ATA_DEV_ATAPI) {
2464 		ata_dev_warn(dev, "WARNING: ATAPI is %s, device ignored\n",
2465 			     atapi_enabled ? "not supported with this driver"
2466 			     : "disabled");
2467 		ata_dev_disable(dev);
2468 		return 0;
2469 	}
2470 
2471 	rc = ata_do_link_spd_horkage(dev);
2472 	if (rc)
2473 		return rc;
2474 
2475 	/* some WD SATA-1 drives have issues with LPM, turn on NOLPM for them */
2476 	if ((dev->horkage & ATA_HORKAGE_WD_BROKEN_LPM) &&
2477 	    (id[ATA_ID_SATA_CAPABILITY] & 0xe) == 0x2)
2478 		dev->horkage |= ATA_HORKAGE_NOLPM;
2479 
2480 	if (ap->flags & ATA_FLAG_NO_LPM)
2481 		dev->horkage |= ATA_HORKAGE_NOLPM;
2482 
2483 	if (dev->horkage & ATA_HORKAGE_NOLPM) {
2484 		ata_dev_warn(dev, "LPM support broken, forcing max_power\n");
2485 		dev->link->ap->target_lpm_policy = ATA_LPM_MAX_POWER;
2486 	}
2487 
2488 	/* let ACPI work its magic */
2489 	rc = ata_acpi_on_devcfg(dev);
2490 	if (rc)
2491 		return rc;
2492 
2493 	/* massage HPA, do it early as it might change IDENTIFY data */
2494 	rc = ata_hpa_resize(dev);
2495 	if (rc)
2496 		return rc;
2497 
2498 	/* print device capabilities */
2499 	if (ata_msg_probe(ap))
2500 		ata_dev_dbg(dev,
2501 			    "%s: cfg 49:%04x 82:%04x 83:%04x 84:%04x "
2502 			    "85:%04x 86:%04x 87:%04x 88:%04x\n",
2503 			    __func__,
2504 			    id[49], id[82], id[83], id[84],
2505 			    id[85], id[86], id[87], id[88]);
2506 
2507 	/* initialize to-be-configured parameters */
2508 	dev->flags &= ~ATA_DFLAG_CFG_MASK;
2509 	dev->max_sectors = 0;
2510 	dev->cdb_len = 0;
2511 	dev->n_sectors = 0;
2512 	dev->cylinders = 0;
2513 	dev->heads = 0;
2514 	dev->sectors = 0;
2515 	dev->multi_count = 0;
2516 
2517 	/*
2518 	 * common ATA, ATAPI feature tests
2519 	 */
2520 
2521 	/* find max transfer mode; for printk only */
2522 	xfer_mask = ata_id_xfermask(id);
2523 
2524 	if (ata_msg_probe(ap))
2525 		ata_dump_id(id);
2526 
2527 	/* SCSI only uses 4-char revisions, dump full 8 chars from ATA */
2528 	ata_id_c_string(dev->id, fwrevbuf, ATA_ID_FW_REV,
2529 			sizeof(fwrevbuf));
2530 
2531 	ata_id_c_string(dev->id, modelbuf, ATA_ID_PROD,
2532 			sizeof(modelbuf));
2533 
2534 	/* ATA-specific feature tests */
2535 	if (dev->class == ATA_DEV_ATA || dev->class == ATA_DEV_ZAC) {
2536 		if (ata_id_is_cfa(id)) {
2537 			/* CPRM may make this media unusable */
2538 			if (id[ATA_ID_CFA_KEY_MGMT] & 1)
2539 				ata_dev_warn(dev,
2540 	"supports DRM functions and may not be fully accessible\n");
2541 			snprintf(revbuf, 7, "CFA");
2542 		} else {
2543 			snprintf(revbuf, 7, "ATA-%d", ata_id_major_version(id));
2544 			/* Warn the user if the device has TPM extensions */
2545 			if (ata_id_has_tpm(id))
2546 				ata_dev_warn(dev,
2547 	"supports DRM functions and may not be fully accessible\n");
2548 		}
2549 
2550 		dev->n_sectors = ata_id_n_sectors(id);
2551 
2552 		/* get current R/W Multiple count setting */
2553 		if ((dev->id[47] >> 8) == 0x80 && (dev->id[59] & 0x100)) {
2554 			unsigned int max = dev->id[47] & 0xff;
2555 			unsigned int cnt = dev->id[59] & 0xff;
2556 			/* only recognize/allow powers of two here */
2557 			if (is_power_of_2(max) && is_power_of_2(cnt))
2558 				if (cnt <= max)
2559 					dev->multi_count = cnt;
2560 		}
2561 
2562 		if (ata_id_has_lba(id)) {
2563 			const char *lba_desc;
2564 			char ncq_desc[24];
2565 
2566 			lba_desc = "LBA";
2567 			dev->flags |= ATA_DFLAG_LBA;
2568 			if (ata_id_has_lba48(id)) {
2569 				dev->flags |= ATA_DFLAG_LBA48;
2570 				lba_desc = "LBA48";
2571 
2572 				if (dev->n_sectors >= (1UL << 28) &&
2573 				    ata_id_has_flush_ext(id))
2574 					dev->flags |= ATA_DFLAG_FLUSH_EXT;
2575 			}
2576 
2577 			/* config NCQ */
2578 			rc = ata_dev_config_ncq(dev, ncq_desc, sizeof(ncq_desc));
2579 			if (rc)
2580 				return rc;
2581 
2582 			/* print device info to dmesg */
2583 			if (ata_msg_drv(ap) && print_info) {
2584 				ata_dev_info(dev, "%s: %s, %s, max %s\n",
2585 					     revbuf, modelbuf, fwrevbuf,
2586 					     ata_mode_string(xfer_mask));
2587 				ata_dev_info(dev,
2588 					     "%llu sectors, multi %u: %s %s\n",
2589 					(unsigned long long)dev->n_sectors,
2590 					dev->multi_count, lba_desc, ncq_desc);
2591 			}
2592 		} else {
2593 			/* CHS */
2594 
2595 			/* Default translation */
2596 			dev->cylinders	= id[1];
2597 			dev->heads	= id[3];
2598 			dev->sectors	= id[6];
2599 
2600 			if (ata_id_current_chs_valid(id)) {
2601 				/* Current CHS translation is valid. */
2602 				dev->cylinders = id[54];
2603 				dev->heads     = id[55];
2604 				dev->sectors   = id[56];
2605 			}
2606 
2607 			/* print device info to dmesg */
2608 			if (ata_msg_drv(ap) && print_info) {
2609 				ata_dev_info(dev, "%s: %s, %s, max %s\n",
2610 					     revbuf,	modelbuf, fwrevbuf,
2611 					     ata_mode_string(xfer_mask));
2612 				ata_dev_info(dev,
2613 					     "%llu sectors, multi %u, CHS %u/%u/%u\n",
2614 					     (unsigned long long)dev->n_sectors,
2615 					     dev->multi_count, dev->cylinders,
2616 					     dev->heads, dev->sectors);
2617 			}
2618 		}
2619 
2620 		/* Check and mark DevSlp capability. Get DevSlp timing variables
2621 		 * from SATA Settings page of Identify Device Data Log.
2622 		 */
2623 		if (ata_id_has_devslp(dev->id)) {
2624 			u8 *sata_setting = ap->sector_buf;
2625 			int i, j;
2626 
2627 			dev->flags |= ATA_DFLAG_DEVSLP;
2628 			err_mask = ata_read_log_page(dev,
2629 						     ATA_LOG_IDENTIFY_DEVICE,
2630 						     ATA_LOG_SATA_SETTINGS,
2631 						     sata_setting,
2632 						     1);
2633 			if (err_mask)
2634 				ata_dev_dbg(dev,
2635 					    "failed to get Identify Device Data, Emask 0x%x\n",
2636 					    err_mask);
2637 			else
2638 				for (i = 0; i < ATA_LOG_DEVSLP_SIZE; i++) {
2639 					j = ATA_LOG_DEVSLP_OFFSET + i;
2640 					dev->devslp_timing[i] = sata_setting[j];
2641 				}
2642 		}
2643 		ata_dev_config_sense_reporting(dev);
2644 		ata_dev_config_zac(dev);
2645 		ata_dev_config_trusted(dev);
2646 		dev->cdb_len = 32;
2647 	}
2648 
2649 	/* ATAPI-specific feature tests */
2650 	else if (dev->class == ATA_DEV_ATAPI) {
2651 		const char *cdb_intr_string = "";
2652 		const char *atapi_an_string = "";
2653 		const char *dma_dir_string = "";
2654 		u32 sntf;
2655 
2656 		rc = atapi_cdb_len(id);
2657 		if ((rc < 12) || (rc > ATAPI_CDB_LEN)) {
2658 			if (ata_msg_warn(ap))
2659 				ata_dev_warn(dev, "unsupported CDB len\n");
2660 			rc = -EINVAL;
2661 			goto err_out_nosup;
2662 		}
2663 		dev->cdb_len = (unsigned int) rc;
2664 
2665 		/* Enable ATAPI AN if both the host and device have
2666 		 * the support.  If PMP is attached, SNTF is required
2667 		 * to enable ATAPI AN to discern between PHY status
2668 		 * changed notifications and ATAPI ANs.
2669 		 */
2670 		if (atapi_an &&
2671 		    (ap->flags & ATA_FLAG_AN) && ata_id_has_atapi_AN(id) &&
2672 		    (!sata_pmp_attached(ap) ||
2673 		     sata_scr_read(&ap->link, SCR_NOTIFICATION, &sntf) == 0)) {
2674 			/* issue SET feature command to turn this on */
2675 			err_mask = ata_dev_set_feature(dev,
2676 					SETFEATURES_SATA_ENABLE, SATA_AN);
2677 			if (err_mask)
2678 				ata_dev_err(dev,
2679 					    "failed to enable ATAPI AN (err_mask=0x%x)\n",
2680 					    err_mask);
2681 			else {
2682 				dev->flags |= ATA_DFLAG_AN;
2683 				atapi_an_string = ", ATAPI AN";
2684 			}
2685 		}
2686 
2687 		if (ata_id_cdb_intr(dev->id)) {
2688 			dev->flags |= ATA_DFLAG_CDB_INTR;
2689 			cdb_intr_string = ", CDB intr";
2690 		}
2691 
2692 		if (atapi_dmadir || (dev->horkage & ATA_HORKAGE_ATAPI_DMADIR) || atapi_id_dmadir(dev->id)) {
2693 			dev->flags |= ATA_DFLAG_DMADIR;
2694 			dma_dir_string = ", DMADIR";
2695 		}
2696 
2697 		if (ata_id_has_da(dev->id)) {
2698 			dev->flags |= ATA_DFLAG_DA;
2699 			zpodd_init(dev);
2700 		}
2701 
2702 		/* print device info to dmesg */
2703 		if (ata_msg_drv(ap) && print_info)
2704 			ata_dev_info(dev,
2705 				     "ATAPI: %s, %s, max %s%s%s%s\n",
2706 				     modelbuf, fwrevbuf,
2707 				     ata_mode_string(xfer_mask),
2708 				     cdb_intr_string, atapi_an_string,
2709 				     dma_dir_string);
2710 	}
2711 
2712 	/* determine max_sectors */
2713 	dev->max_sectors = ATA_MAX_SECTORS;
2714 	if (dev->flags & ATA_DFLAG_LBA48)
2715 		dev->max_sectors = ATA_MAX_SECTORS_LBA48;
2716 
2717 	/* Limit PATA drive on SATA cable bridge transfers to udma5,
2718 	   200 sectors */
2719 	if (ata_dev_knobble(dev)) {
2720 		if (ata_msg_drv(ap) && print_info)
2721 			ata_dev_info(dev, "applying bridge limits\n");
2722 		dev->udma_mask &= ATA_UDMA5;
2723 		dev->max_sectors = ATA_MAX_SECTORS;
2724 	}
2725 
2726 	if ((dev->class == ATA_DEV_ATAPI) &&
2727 	    (atapi_command_packet_set(id) == TYPE_TAPE)) {
2728 		dev->max_sectors = ATA_MAX_SECTORS_TAPE;
2729 		dev->horkage |= ATA_HORKAGE_STUCK_ERR;
2730 	}
2731 
2732 	if (dev->horkage & ATA_HORKAGE_MAX_SEC_128)
2733 		dev->max_sectors = min_t(unsigned int, ATA_MAX_SECTORS_128,
2734 					 dev->max_sectors);
2735 
2736 	if (dev->horkage & ATA_HORKAGE_MAX_SEC_1024)
2737 		dev->max_sectors = min_t(unsigned int, ATA_MAX_SECTORS_1024,
2738 					 dev->max_sectors);
2739 
2740 	if (dev->horkage & ATA_HORKAGE_MAX_SEC_LBA48)
2741 		dev->max_sectors = ATA_MAX_SECTORS_LBA48;
2742 
2743 	if (ap->ops->dev_config)
2744 		ap->ops->dev_config(dev);
2745 
2746 	if (dev->horkage & ATA_HORKAGE_DIAGNOSTIC) {
2747 		/* Let the user know. We don't want to disallow opens for
2748 		   rescue purposes, or in case the vendor is just a blithering
2749 		   idiot. Do this after the dev_config call as some controllers
2750 		   with buggy firmware may want to avoid reporting false device
2751 		   bugs */
2752 
2753 		if (print_info) {
2754 			ata_dev_warn(dev,
2755 "Drive reports diagnostics failure. This may indicate a drive\n");
2756 			ata_dev_warn(dev,
2757 "fault or invalid emulation. Contact drive vendor for information.\n");
2758 		}
2759 	}
2760 
2761 	if ((dev->horkage & ATA_HORKAGE_FIRMWARE_WARN) && print_info) {
2762 		ata_dev_warn(dev, "WARNING: device requires firmware update to be fully functional\n");
2763 		ata_dev_warn(dev, "         contact the vendor or visit http://ata.wiki.kernel.org\n");
2764 	}
2765 
2766 	return 0;
2767 
2768 err_out_nosup:
2769 	if (ata_msg_probe(ap))
2770 		ata_dev_dbg(dev, "%s: EXIT, err\n", __func__);
2771 	return rc;
2772 }
2773 
2774 /**
2775  *	ata_cable_40wire	-	return 40 wire cable type
2776  *	@ap: port
2777  *
2778  *	Helper method for drivers which want to hardwire 40 wire cable
2779  *	detection.
2780  */
2781 
2782 int ata_cable_40wire(struct ata_port *ap)
2783 {
2784 	return ATA_CBL_PATA40;
2785 }
2786 
2787 /**
2788  *	ata_cable_80wire	-	return 80 wire cable type
2789  *	@ap: port
2790  *
2791  *	Helper method for drivers which want to hardwire 80 wire cable
2792  *	detection.
2793  */
2794 
2795 int ata_cable_80wire(struct ata_port *ap)
2796 {
2797 	return ATA_CBL_PATA80;
2798 }
2799 
2800 /**
2801  *	ata_cable_unknown	-	return unknown PATA cable.
2802  *	@ap: port
2803  *
2804  *	Helper method for drivers which have no PATA cable detection.
2805  */
2806 
2807 int ata_cable_unknown(struct ata_port *ap)
2808 {
2809 	return ATA_CBL_PATA_UNK;
2810 }
2811 
2812 /**
2813  *	ata_cable_ignore	-	return ignored PATA cable.
2814  *	@ap: port
2815  *
2816  *	Helper method for drivers which don't use cable type to limit
2817  *	transfer mode.
2818  */
2819 int ata_cable_ignore(struct ata_port *ap)
2820 {
2821 	return ATA_CBL_PATA_IGN;
2822 }
2823 
2824 /**
2825  *	ata_cable_sata	-	return SATA cable type
2826  *	@ap: port
2827  *
2828  *	Helper method for drivers which have SATA cables
2829  */
2830 
2831 int ata_cable_sata(struct ata_port *ap)
2832 {
2833 	return ATA_CBL_SATA;
2834 }
2835 
2836 /**
2837  *	ata_bus_probe - Reset and probe ATA bus
2838  *	@ap: Bus to probe
2839  *
2840  *	Master ATA bus probing function.  Initiates a hardware-dependent
2841  *	bus reset, then attempts to identify any devices found on
2842  *	the bus.
2843  *
2844  *	LOCKING:
2845  *	PCI/etc. bus probe sem.
2846  *
2847  *	RETURNS:
2848  *	Zero on success, negative errno otherwise.
2849  */
2850 
2851 int ata_bus_probe(struct ata_port *ap)
2852 {
2853 	unsigned int classes[ATA_MAX_DEVICES];
2854 	int tries[ATA_MAX_DEVICES];
2855 	int rc;
2856 	struct ata_device *dev;
2857 
2858 	ata_for_each_dev(dev, &ap->link, ALL)
2859 		tries[dev->devno] = ATA_PROBE_MAX_TRIES;
2860 
2861  retry:
2862 	ata_for_each_dev(dev, &ap->link, ALL) {
2863 		/* If we issue an SRST then an ATA drive (not ATAPI)
2864 		 * may change configuration and be in PIO0 timing. If
2865 		 * we do a hard reset (or are coming from power on)
2866 		 * this is true for ATA or ATAPI. Until we've set a
2867 		 * suitable controller mode we should not touch the
2868 		 * bus as we may be talking too fast.
2869 		 */
2870 		dev->pio_mode = XFER_PIO_0;
2871 		dev->dma_mode = 0xff;
2872 
2873 		/* If the controller has a pio mode setup function
2874 		 * then use it to set the chipset to rights. Don't
2875 		 * touch the DMA setup as that will be dealt with when
2876 		 * configuring devices.
2877 		 */
2878 		if (ap->ops->set_piomode)
2879 			ap->ops->set_piomode(ap, dev);
2880 	}
2881 
2882 	/* reset and determine device classes */
2883 	ap->ops->phy_reset(ap);
2884 
2885 	ata_for_each_dev(dev, &ap->link, ALL) {
2886 		if (dev->class != ATA_DEV_UNKNOWN)
2887 			classes[dev->devno] = dev->class;
2888 		else
2889 			classes[dev->devno] = ATA_DEV_NONE;
2890 
2891 		dev->class = ATA_DEV_UNKNOWN;
2892 	}
2893 
2894 	/* read IDENTIFY page and configure devices. We have to do the identify
2895 	   specific sequence bass-ackwards so that PDIAG- is released by
2896 	   the slave device */
2897 
2898 	ata_for_each_dev(dev, &ap->link, ALL_REVERSE) {
2899 		if (tries[dev->devno])
2900 			dev->class = classes[dev->devno];
2901 
2902 		if (!ata_dev_enabled(dev))
2903 			continue;
2904 
2905 		rc = ata_dev_read_id(dev, &dev->class, ATA_READID_POSTRESET,
2906 				     dev->id);
2907 		if (rc)
2908 			goto fail;
2909 	}
2910 
2911 	/* Now ask for the cable type as PDIAG- should have been released */
2912 	if (ap->ops->cable_detect)
2913 		ap->cbl = ap->ops->cable_detect(ap);
2914 
2915 	/* We may have SATA bridge glue hiding here irrespective of
2916 	 * the reported cable types and sensed types.  When SATA
2917 	 * drives indicate we have a bridge, we don't know which end
2918 	 * of the link the bridge is which is a problem.
2919 	 */
2920 	ata_for_each_dev(dev, &ap->link, ENABLED)
2921 		if (ata_id_is_sata(dev->id))
2922 			ap->cbl = ATA_CBL_SATA;
2923 
2924 	/* After the identify sequence we can now set up the devices. We do
2925 	   this in the normal order so that the user doesn't get confused */
2926 
2927 	ata_for_each_dev(dev, &ap->link, ENABLED) {
2928 		ap->link.eh_context.i.flags |= ATA_EHI_PRINTINFO;
2929 		rc = ata_dev_configure(dev);
2930 		ap->link.eh_context.i.flags &= ~ATA_EHI_PRINTINFO;
2931 		if (rc)
2932 			goto fail;
2933 	}
2934 
2935 	/* configure transfer mode */
2936 	rc = ata_set_mode(&ap->link, &dev);
2937 	if (rc)
2938 		goto fail;
2939 
2940 	ata_for_each_dev(dev, &ap->link, ENABLED)
2941 		return 0;
2942 
2943 	return -ENODEV;
2944 
2945  fail:
2946 	tries[dev->devno]--;
2947 
2948 	switch (rc) {
2949 	case -EINVAL:
2950 		/* eeek, something went very wrong, give up */
2951 		tries[dev->devno] = 0;
2952 		break;
2953 
2954 	case -ENODEV:
2955 		/* give it just one more chance */
2956 		tries[dev->devno] = min(tries[dev->devno], 1);
2957 		/* fall through */
2958 	case -EIO:
2959 		if (tries[dev->devno] == 1) {
2960 			/* This is the last chance, better to slow
2961 			 * down than lose it.
2962 			 */
2963 			sata_down_spd_limit(&ap->link, 0);
2964 			ata_down_xfermask_limit(dev, ATA_DNXFER_PIO);
2965 		}
2966 	}
2967 
2968 	if (!tries[dev->devno])
2969 		ata_dev_disable(dev);
2970 
2971 	goto retry;
2972 }
2973 
2974 /**
2975  *	sata_print_link_status - Print SATA link status
2976  *	@link: SATA link to printk link status about
2977  *
2978  *	This function prints link speed and status of a SATA link.
2979  *
2980  *	LOCKING:
2981  *	None.
2982  */
2983 static void sata_print_link_status(struct ata_link *link)
2984 {
2985 	u32 sstatus, scontrol, tmp;
2986 
2987 	if (sata_scr_read(link, SCR_STATUS, &sstatus))
2988 		return;
2989 	sata_scr_read(link, SCR_CONTROL, &scontrol);
2990 
2991 	if (ata_phys_link_online(link)) {
2992 		tmp = (sstatus >> 4) & 0xf;
2993 		ata_link_info(link, "SATA link up %s (SStatus %X SControl %X)\n",
2994 			      sata_spd_string(tmp), sstatus, scontrol);
2995 	} else {
2996 		ata_link_info(link, "SATA link down (SStatus %X SControl %X)\n",
2997 			      sstatus, scontrol);
2998 	}
2999 }
3000 
3001 /**
3002  *	ata_dev_pair		-	return other device on cable
3003  *	@adev: device
3004  *
3005  *	Obtain the other device on the same cable, or if none is
3006  *	present NULL is returned
3007  */
3008 
3009 struct ata_device *ata_dev_pair(struct ata_device *adev)
3010 {
3011 	struct ata_link *link = adev->link;
3012 	struct ata_device *pair = &link->device[1 - adev->devno];
3013 	if (!ata_dev_enabled(pair))
3014 		return NULL;
3015 	return pair;
3016 }
3017 
3018 /**
3019  *	sata_down_spd_limit - adjust SATA spd limit downward
3020  *	@link: Link to adjust SATA spd limit for
3021  *	@spd_limit: Additional limit
3022  *
3023  *	Adjust SATA spd limit of @link downward.  Note that this
3024  *	function only adjusts the limit.  The change must be applied
3025  *	using sata_set_spd().
3026  *
3027  *	If @spd_limit is non-zero, the speed is limited to equal to or
3028  *	lower than @spd_limit if such speed is supported.  If
3029  *	@spd_limit is slower than any supported speed, only the lowest
3030  *	supported speed is allowed.
3031  *
3032  *	LOCKING:
3033  *	Inherited from caller.
3034  *
3035  *	RETURNS:
3036  *	0 on success, negative errno on failure
3037  */
3038 int sata_down_spd_limit(struct ata_link *link, u32 spd_limit)
3039 {
3040 	u32 sstatus, spd, mask;
3041 	int rc, bit;
3042 
3043 	if (!sata_scr_valid(link))
3044 		return -EOPNOTSUPP;
3045 
3046 	/* If SCR can be read, use it to determine the current SPD.
3047 	 * If not, use cached value in link->sata_spd.
3048 	 */
3049 	rc = sata_scr_read(link, SCR_STATUS, &sstatus);
3050 	if (rc == 0 && ata_sstatus_online(sstatus))
3051 		spd = (sstatus >> 4) & 0xf;
3052 	else
3053 		spd = link->sata_spd;
3054 
3055 	mask = link->sata_spd_limit;
3056 	if (mask <= 1)
3057 		return -EINVAL;
3058 
3059 	/* unconditionally mask off the highest bit */
3060 	bit = fls(mask) - 1;
3061 	mask &= ~(1 << bit);
3062 
3063 	/*
3064 	 * Mask off all speeds higher than or equal to the current one.  At
3065 	 * this point, if current SPD is not available and we previously
3066 	 * recorded the link speed from SStatus, the driver has already
3067 	 * masked off the highest bit so mask should already be 1 or 0.
3068 	 * Otherwise, we should not force 1.5Gbps on a link where we have
3069 	 * not previously recorded speed from SStatus.  Just return in this
3070 	 * case.
3071 	 */
3072 	if (spd > 1)
3073 		mask &= (1 << (spd - 1)) - 1;
3074 	else
3075 		return -EINVAL;
3076 
3077 	/* were we already at the bottom? */
3078 	if (!mask)
3079 		return -EINVAL;
3080 
3081 	if (spd_limit) {
3082 		if (mask & ((1 << spd_limit) - 1))
3083 			mask &= (1 << spd_limit) - 1;
3084 		else {
3085 			bit = ffs(mask) - 1;
3086 			mask = 1 << bit;
3087 		}
3088 	}
3089 
3090 	link->sata_spd_limit = mask;
3091 
3092 	ata_link_warn(link, "limiting SATA link speed to %s\n",
3093 		      sata_spd_string(fls(mask)));
3094 
3095 	return 0;
3096 }
3097 
3098 static int __sata_set_spd_needed(struct ata_link *link, u32 *scontrol)
3099 {
3100 	struct ata_link *host_link = &link->ap->link;
3101 	u32 limit, target, spd;
3102 
3103 	limit = link->sata_spd_limit;
3104 
3105 	/* Don't configure downstream link faster than upstream link.
3106 	 * It doesn't speed up anything and some PMPs choke on such
3107 	 * configuration.
3108 	 */
3109 	if (!ata_is_host_link(link) && host_link->sata_spd)
3110 		limit &= (1 << host_link->sata_spd) - 1;
3111 
3112 	if (limit == UINT_MAX)
3113 		target = 0;
3114 	else
3115 		target = fls(limit);
3116 
3117 	spd = (*scontrol >> 4) & 0xf;
3118 	*scontrol = (*scontrol & ~0xf0) | ((target & 0xf) << 4);
3119 
3120 	return spd != target;
3121 }
3122 
3123 /**
3124  *	sata_set_spd_needed - is SATA spd configuration needed
3125  *	@link: Link in question
3126  *
3127  *	Test whether the spd limit in SControl matches
3128  *	@link->sata_spd_limit.  This function is used to determine
3129  *	whether hardreset is necessary to apply SATA spd
3130  *	configuration.
3131  *
3132  *	LOCKING:
3133  *	Inherited from caller.
3134  *
3135  *	RETURNS:
3136  *	1 if SATA spd configuration is needed, 0 otherwise.
3137  */
3138 static int sata_set_spd_needed(struct ata_link *link)
3139 {
3140 	u32 scontrol;
3141 
3142 	if (sata_scr_read(link, SCR_CONTROL, &scontrol))
3143 		return 1;
3144 
3145 	return __sata_set_spd_needed(link, &scontrol);
3146 }
3147 
3148 /**
3149  *	sata_set_spd - set SATA spd according to spd limit
3150  *	@link: Link to set SATA spd for
3151  *
3152  *	Set SATA spd of @link according to sata_spd_limit.
3153  *
3154  *	LOCKING:
3155  *	Inherited from caller.
3156  *
3157  *	RETURNS:
3158  *	0 if spd doesn't need to be changed, 1 if spd has been
3159  *	changed.  Negative errno if SCR registers are inaccessible.
3160  */
3161 int sata_set_spd(struct ata_link *link)
3162 {
3163 	u32 scontrol;
3164 	int rc;
3165 
3166 	if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3167 		return rc;
3168 
3169 	if (!__sata_set_spd_needed(link, &scontrol))
3170 		return 0;
3171 
3172 	if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
3173 		return rc;
3174 
3175 	return 1;
3176 }
3177 
3178 /*
3179  * This mode timing computation functionality is ported over from
3180  * drivers/ide/ide-timing.h and was originally written by Vojtech Pavlik
3181  */
3182 /*
3183  * PIO 0-4, MWDMA 0-2 and UDMA 0-6 timings (in nanoseconds).
3184  * These were taken from ATA/ATAPI-6 standard, rev 0a, except
3185  * for UDMA6, which is currently supported only by Maxtor drives.
3186  *
3187  * For PIO 5/6 MWDMA 3/4 see the CFA specification 3.0.
3188  */
3189 
3190 static const struct ata_timing ata_timing[] = {
3191 /*	{ XFER_PIO_SLOW, 120, 290, 240, 960, 290, 240, 0,  960,   0 }, */
3192 	{ XFER_PIO_0,     70, 290, 240, 600, 165, 150, 0,  600,   0 },
3193 	{ XFER_PIO_1,     50, 290,  93, 383, 125, 100, 0,  383,   0 },
3194 	{ XFER_PIO_2,     30, 290,  40, 330, 100,  90, 0,  240,   0 },
3195 	{ XFER_PIO_3,     30,  80,  70, 180,  80,  70, 0,  180,   0 },
3196 	{ XFER_PIO_4,     25,  70,  25, 120,  70,  25, 0,  120,   0 },
3197 	{ XFER_PIO_5,     15,  65,  25, 100,  65,  25, 0,  100,   0 },
3198 	{ XFER_PIO_6,     10,  55,  20,  80,  55,  20, 0,   80,   0 },
3199 
3200 	{ XFER_SW_DMA_0, 120,   0,   0,   0, 480, 480, 50, 960,   0 },
3201 	{ XFER_SW_DMA_1,  90,   0,   0,   0, 240, 240, 30, 480,   0 },
3202 	{ XFER_SW_DMA_2,  60,   0,   0,   0, 120, 120, 20, 240,   0 },
3203 
3204 	{ XFER_MW_DMA_0,  60,   0,   0,   0, 215, 215, 20, 480,   0 },
3205 	{ XFER_MW_DMA_1,  45,   0,   0,   0,  80,  50, 5,  150,   0 },
3206 	{ XFER_MW_DMA_2,  25,   0,   0,   0,  70,  25, 5,  120,   0 },
3207 	{ XFER_MW_DMA_3,  25,   0,   0,   0,  65,  25, 5,  100,   0 },
3208 	{ XFER_MW_DMA_4,  25,   0,   0,   0,  55,  20, 5,   80,   0 },
3209 
3210 /*	{ XFER_UDMA_SLOW,  0,   0,   0,   0,   0,   0, 0,    0, 150 }, */
3211 	{ XFER_UDMA_0,     0,   0,   0,   0,   0,   0, 0,    0, 120 },
3212 	{ XFER_UDMA_1,     0,   0,   0,   0,   0,   0, 0,    0,  80 },
3213 	{ XFER_UDMA_2,     0,   0,   0,   0,   0,   0, 0,    0,  60 },
3214 	{ XFER_UDMA_3,     0,   0,   0,   0,   0,   0, 0,    0,  45 },
3215 	{ XFER_UDMA_4,     0,   0,   0,   0,   0,   0, 0,    0,  30 },
3216 	{ XFER_UDMA_5,     0,   0,   0,   0,   0,   0, 0,    0,  20 },
3217 	{ XFER_UDMA_6,     0,   0,   0,   0,   0,   0, 0,    0,  15 },
3218 
3219 	{ 0xFF }
3220 };
3221 
3222 #define ENOUGH(v, unit)		(((v)-1)/(unit)+1)
3223 #define EZ(v, unit)		((v)?ENOUGH(((v) * 1000), unit):0)
3224 
3225 static void ata_timing_quantize(const struct ata_timing *t, struct ata_timing *q, int T, int UT)
3226 {
3227 	q->setup	= EZ(t->setup,       T);
3228 	q->act8b	= EZ(t->act8b,       T);
3229 	q->rec8b	= EZ(t->rec8b,       T);
3230 	q->cyc8b	= EZ(t->cyc8b,       T);
3231 	q->active	= EZ(t->active,      T);
3232 	q->recover	= EZ(t->recover,     T);
3233 	q->dmack_hold	= EZ(t->dmack_hold,  T);
3234 	q->cycle	= EZ(t->cycle,       T);
3235 	q->udma		= EZ(t->udma,       UT);
3236 }
3237 
3238 void ata_timing_merge(const struct ata_timing *a, const struct ata_timing *b,
3239 		      struct ata_timing *m, unsigned int what)
3240 {
3241 	if (what & ATA_TIMING_SETUP  ) m->setup   = max(a->setup,   b->setup);
3242 	if (what & ATA_TIMING_ACT8B  ) m->act8b   = max(a->act8b,   b->act8b);
3243 	if (what & ATA_TIMING_REC8B  ) m->rec8b   = max(a->rec8b,   b->rec8b);
3244 	if (what & ATA_TIMING_CYC8B  ) m->cyc8b   = max(a->cyc8b,   b->cyc8b);
3245 	if (what & ATA_TIMING_ACTIVE ) m->active  = max(a->active,  b->active);
3246 	if (what & ATA_TIMING_RECOVER) m->recover = max(a->recover, b->recover);
3247 	if (what & ATA_TIMING_DMACK_HOLD) m->dmack_hold = max(a->dmack_hold, b->dmack_hold);
3248 	if (what & ATA_TIMING_CYCLE  ) m->cycle   = max(a->cycle,   b->cycle);
3249 	if (what & ATA_TIMING_UDMA   ) m->udma    = max(a->udma,    b->udma);
3250 }
3251 
3252 const struct ata_timing *ata_timing_find_mode(u8 xfer_mode)
3253 {
3254 	const struct ata_timing *t = ata_timing;
3255 
3256 	while (xfer_mode > t->mode)
3257 		t++;
3258 
3259 	if (xfer_mode == t->mode)
3260 		return t;
3261 
3262 	WARN_ONCE(true, "%s: unable to find timing for xfer_mode 0x%x\n",
3263 			__func__, xfer_mode);
3264 
3265 	return NULL;
3266 }
3267 
3268 int ata_timing_compute(struct ata_device *adev, unsigned short speed,
3269 		       struct ata_timing *t, int T, int UT)
3270 {
3271 	const u16 *id = adev->id;
3272 	const struct ata_timing *s;
3273 	struct ata_timing p;
3274 
3275 	/*
3276 	 * Find the mode.
3277 	 */
3278 
3279 	if (!(s = ata_timing_find_mode(speed)))
3280 		return -EINVAL;
3281 
3282 	memcpy(t, s, sizeof(*s));
3283 
3284 	/*
3285 	 * If the drive is an EIDE drive, it can tell us it needs extended
3286 	 * PIO/MW_DMA cycle timing.
3287 	 */
3288 
3289 	if (id[ATA_ID_FIELD_VALID] & 2) {	/* EIDE drive */
3290 		memset(&p, 0, sizeof(p));
3291 
3292 		if (speed >= XFER_PIO_0 && speed < XFER_SW_DMA_0) {
3293 			if (speed <= XFER_PIO_2)
3294 				p.cycle = p.cyc8b = id[ATA_ID_EIDE_PIO];
3295 			else if ((speed <= XFER_PIO_4) ||
3296 				 (speed == XFER_PIO_5 && !ata_id_is_cfa(id)))
3297 				p.cycle = p.cyc8b = id[ATA_ID_EIDE_PIO_IORDY];
3298 		} else if (speed >= XFER_MW_DMA_0 && speed <= XFER_MW_DMA_2)
3299 			p.cycle = id[ATA_ID_EIDE_DMA_MIN];
3300 
3301 		ata_timing_merge(&p, t, t, ATA_TIMING_CYCLE | ATA_TIMING_CYC8B);
3302 	}
3303 
3304 	/*
3305 	 * Convert the timing to bus clock counts.
3306 	 */
3307 
3308 	ata_timing_quantize(t, t, T, UT);
3309 
3310 	/*
3311 	 * Even in DMA/UDMA modes we still use PIO access for IDENTIFY,
3312 	 * S.M.A.R.T * and some other commands. We have to ensure that the
3313 	 * DMA cycle timing is slower/equal than the fastest PIO timing.
3314 	 */
3315 
3316 	if (speed > XFER_PIO_6) {
3317 		ata_timing_compute(adev, adev->pio_mode, &p, T, UT);
3318 		ata_timing_merge(&p, t, t, ATA_TIMING_ALL);
3319 	}
3320 
3321 	/*
3322 	 * Lengthen active & recovery time so that cycle time is correct.
3323 	 */
3324 
3325 	if (t->act8b + t->rec8b < t->cyc8b) {
3326 		t->act8b += (t->cyc8b - (t->act8b + t->rec8b)) / 2;
3327 		t->rec8b = t->cyc8b - t->act8b;
3328 	}
3329 
3330 	if (t->active + t->recover < t->cycle) {
3331 		t->active += (t->cycle - (t->active + t->recover)) / 2;
3332 		t->recover = t->cycle - t->active;
3333 	}
3334 
3335 	/* In a few cases quantisation may produce enough errors to
3336 	   leave t->cycle too low for the sum of active and recovery
3337 	   if so we must correct this */
3338 	if (t->active + t->recover > t->cycle)
3339 		t->cycle = t->active + t->recover;
3340 
3341 	return 0;
3342 }
3343 
3344 /**
3345  *	ata_timing_cycle2mode - find xfer mode for the specified cycle duration
3346  *	@xfer_shift: ATA_SHIFT_* value for transfer type to examine.
3347  *	@cycle: cycle duration in ns
3348  *
3349  *	Return matching xfer mode for @cycle.  The returned mode is of
3350  *	the transfer type specified by @xfer_shift.  If @cycle is too
3351  *	slow for @xfer_shift, 0xff is returned.  If @cycle is faster
3352  *	than the fastest known mode, the fasted mode is returned.
3353  *
3354  *	LOCKING:
3355  *	None.
3356  *
3357  *	RETURNS:
3358  *	Matching xfer_mode, 0xff if no match found.
3359  */
3360 u8 ata_timing_cycle2mode(unsigned int xfer_shift, int cycle)
3361 {
3362 	u8 base_mode = 0xff, last_mode = 0xff;
3363 	const struct ata_xfer_ent *ent;
3364 	const struct ata_timing *t;
3365 
3366 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
3367 		if (ent->shift == xfer_shift)
3368 			base_mode = ent->base;
3369 
3370 	for (t = ata_timing_find_mode(base_mode);
3371 	     t && ata_xfer_mode2shift(t->mode) == xfer_shift; t++) {
3372 		unsigned short this_cycle;
3373 
3374 		switch (xfer_shift) {
3375 		case ATA_SHIFT_PIO:
3376 		case ATA_SHIFT_MWDMA:
3377 			this_cycle = t->cycle;
3378 			break;
3379 		case ATA_SHIFT_UDMA:
3380 			this_cycle = t->udma;
3381 			break;
3382 		default:
3383 			return 0xff;
3384 		}
3385 
3386 		if (cycle > this_cycle)
3387 			break;
3388 
3389 		last_mode = t->mode;
3390 	}
3391 
3392 	return last_mode;
3393 }
3394 
3395 /**
3396  *	ata_down_xfermask_limit - adjust dev xfer masks downward
3397  *	@dev: Device to adjust xfer masks
3398  *	@sel: ATA_DNXFER_* selector
3399  *
3400  *	Adjust xfer masks of @dev downward.  Note that this function
3401  *	does not apply the change.  Invoking ata_set_mode() afterwards
3402  *	will apply the limit.
3403  *
3404  *	LOCKING:
3405  *	Inherited from caller.
3406  *
3407  *	RETURNS:
3408  *	0 on success, negative errno on failure
3409  */
3410 int ata_down_xfermask_limit(struct ata_device *dev, unsigned int sel)
3411 {
3412 	char buf[32];
3413 	unsigned long orig_mask, xfer_mask;
3414 	unsigned long pio_mask, mwdma_mask, udma_mask;
3415 	int quiet, highbit;
3416 
3417 	quiet = !!(sel & ATA_DNXFER_QUIET);
3418 	sel &= ~ATA_DNXFER_QUIET;
3419 
3420 	xfer_mask = orig_mask = ata_pack_xfermask(dev->pio_mask,
3421 						  dev->mwdma_mask,
3422 						  dev->udma_mask);
3423 	ata_unpack_xfermask(xfer_mask, &pio_mask, &mwdma_mask, &udma_mask);
3424 
3425 	switch (sel) {
3426 	case ATA_DNXFER_PIO:
3427 		highbit = fls(pio_mask) - 1;
3428 		pio_mask &= ~(1 << highbit);
3429 		break;
3430 
3431 	case ATA_DNXFER_DMA:
3432 		if (udma_mask) {
3433 			highbit = fls(udma_mask) - 1;
3434 			udma_mask &= ~(1 << highbit);
3435 			if (!udma_mask)
3436 				return -ENOENT;
3437 		} else if (mwdma_mask) {
3438 			highbit = fls(mwdma_mask) - 1;
3439 			mwdma_mask &= ~(1 << highbit);
3440 			if (!mwdma_mask)
3441 				return -ENOENT;
3442 		}
3443 		break;
3444 
3445 	case ATA_DNXFER_40C:
3446 		udma_mask &= ATA_UDMA_MASK_40C;
3447 		break;
3448 
3449 	case ATA_DNXFER_FORCE_PIO0:
3450 		pio_mask &= 1;
3451 		/* fall through */
3452 	case ATA_DNXFER_FORCE_PIO:
3453 		mwdma_mask = 0;
3454 		udma_mask = 0;
3455 		break;
3456 
3457 	default:
3458 		BUG();
3459 	}
3460 
3461 	xfer_mask &= ata_pack_xfermask(pio_mask, mwdma_mask, udma_mask);
3462 
3463 	if (!(xfer_mask & ATA_MASK_PIO) || xfer_mask == orig_mask)
3464 		return -ENOENT;
3465 
3466 	if (!quiet) {
3467 		if (xfer_mask & (ATA_MASK_MWDMA | ATA_MASK_UDMA))
3468 			snprintf(buf, sizeof(buf), "%s:%s",
3469 				 ata_mode_string(xfer_mask),
3470 				 ata_mode_string(xfer_mask & ATA_MASK_PIO));
3471 		else
3472 			snprintf(buf, sizeof(buf), "%s",
3473 				 ata_mode_string(xfer_mask));
3474 
3475 		ata_dev_warn(dev, "limiting speed to %s\n", buf);
3476 	}
3477 
3478 	ata_unpack_xfermask(xfer_mask, &dev->pio_mask, &dev->mwdma_mask,
3479 			    &dev->udma_mask);
3480 
3481 	return 0;
3482 }
3483 
3484 static int ata_dev_set_mode(struct ata_device *dev)
3485 {
3486 	struct ata_port *ap = dev->link->ap;
3487 	struct ata_eh_context *ehc = &dev->link->eh_context;
3488 	const bool nosetxfer = dev->horkage & ATA_HORKAGE_NOSETXFER;
3489 	const char *dev_err_whine = "";
3490 	int ign_dev_err = 0;
3491 	unsigned int err_mask = 0;
3492 	int rc;
3493 
3494 	dev->flags &= ~ATA_DFLAG_PIO;
3495 	if (dev->xfer_shift == ATA_SHIFT_PIO)
3496 		dev->flags |= ATA_DFLAG_PIO;
3497 
3498 	if (nosetxfer && ap->flags & ATA_FLAG_SATA && ata_id_is_sata(dev->id))
3499 		dev_err_whine = " (SET_XFERMODE skipped)";
3500 	else {
3501 		if (nosetxfer)
3502 			ata_dev_warn(dev,
3503 				     "NOSETXFER but PATA detected - can't "
3504 				     "skip SETXFER, might malfunction\n");
3505 		err_mask = ata_dev_set_xfermode(dev);
3506 	}
3507 
3508 	if (err_mask & ~AC_ERR_DEV)
3509 		goto fail;
3510 
3511 	/* revalidate */
3512 	ehc->i.flags |= ATA_EHI_POST_SETMODE;
3513 	rc = ata_dev_revalidate(dev, ATA_DEV_UNKNOWN, 0);
3514 	ehc->i.flags &= ~ATA_EHI_POST_SETMODE;
3515 	if (rc)
3516 		return rc;
3517 
3518 	if (dev->xfer_shift == ATA_SHIFT_PIO) {
3519 		/* Old CFA may refuse this command, which is just fine */
3520 		if (ata_id_is_cfa(dev->id))
3521 			ign_dev_err = 1;
3522 		/* Catch several broken garbage emulations plus some pre
3523 		   ATA devices */
3524 		if (ata_id_major_version(dev->id) == 0 &&
3525 					dev->pio_mode <= XFER_PIO_2)
3526 			ign_dev_err = 1;
3527 		/* Some very old devices and some bad newer ones fail
3528 		   any kind of SET_XFERMODE request but support PIO0-2
3529 		   timings and no IORDY */
3530 		if (!ata_id_has_iordy(dev->id) && dev->pio_mode <= XFER_PIO_2)
3531 			ign_dev_err = 1;
3532 	}
3533 	/* Early MWDMA devices do DMA but don't allow DMA mode setting.
3534 	   Don't fail an MWDMA0 set IFF the device indicates it is in MWDMA0 */
3535 	if (dev->xfer_shift == ATA_SHIFT_MWDMA &&
3536 	    dev->dma_mode == XFER_MW_DMA_0 &&
3537 	    (dev->id[63] >> 8) & 1)
3538 		ign_dev_err = 1;
3539 
3540 	/* if the device is actually configured correctly, ignore dev err */
3541 	if (dev->xfer_mode == ata_xfer_mask2mode(ata_id_xfermask(dev->id)))
3542 		ign_dev_err = 1;
3543 
3544 	if (err_mask & AC_ERR_DEV) {
3545 		if (!ign_dev_err)
3546 			goto fail;
3547 		else
3548 			dev_err_whine = " (device error ignored)";
3549 	}
3550 
3551 	DPRINTK("xfer_shift=%u, xfer_mode=0x%x\n",
3552 		dev->xfer_shift, (int)dev->xfer_mode);
3553 
3554 	if (!(ehc->i.flags & ATA_EHI_QUIET) ||
3555 	    ehc->i.flags & ATA_EHI_DID_HARDRESET)
3556 		ata_dev_info(dev, "configured for %s%s\n",
3557 			     ata_mode_string(ata_xfer_mode2mask(dev->xfer_mode)),
3558 			     dev_err_whine);
3559 
3560 	return 0;
3561 
3562  fail:
3563 	ata_dev_err(dev, "failed to set xfermode (err_mask=0x%x)\n", err_mask);
3564 	return -EIO;
3565 }
3566 
3567 /**
3568  *	ata_do_set_mode - Program timings and issue SET FEATURES - XFER
3569  *	@link: link on which timings will be programmed
3570  *	@r_failed_dev: out parameter for failed device
3571  *
3572  *	Standard implementation of the function used to tune and set
3573  *	ATA device disk transfer mode (PIO3, UDMA6, etc.).  If
3574  *	ata_dev_set_mode() fails, pointer to the failing device is
3575  *	returned in @r_failed_dev.
3576  *
3577  *	LOCKING:
3578  *	PCI/etc. bus probe sem.
3579  *
3580  *	RETURNS:
3581  *	0 on success, negative errno otherwise
3582  */
3583 
3584 int ata_do_set_mode(struct ata_link *link, struct ata_device **r_failed_dev)
3585 {
3586 	struct ata_port *ap = link->ap;
3587 	struct ata_device *dev;
3588 	int rc = 0, used_dma = 0, found = 0;
3589 
3590 	/* step 1: calculate xfer_mask */
3591 	ata_for_each_dev(dev, link, ENABLED) {
3592 		unsigned long pio_mask, dma_mask;
3593 		unsigned int mode_mask;
3594 
3595 		mode_mask = ATA_DMA_MASK_ATA;
3596 		if (dev->class == ATA_DEV_ATAPI)
3597 			mode_mask = ATA_DMA_MASK_ATAPI;
3598 		else if (ata_id_is_cfa(dev->id))
3599 			mode_mask = ATA_DMA_MASK_CFA;
3600 
3601 		ata_dev_xfermask(dev);
3602 		ata_force_xfermask(dev);
3603 
3604 		pio_mask = ata_pack_xfermask(dev->pio_mask, 0, 0);
3605 
3606 		if (libata_dma_mask & mode_mask)
3607 			dma_mask = ata_pack_xfermask(0, dev->mwdma_mask,
3608 						     dev->udma_mask);
3609 		else
3610 			dma_mask = 0;
3611 
3612 		dev->pio_mode = ata_xfer_mask2mode(pio_mask);
3613 		dev->dma_mode = ata_xfer_mask2mode(dma_mask);
3614 
3615 		found = 1;
3616 		if (ata_dma_enabled(dev))
3617 			used_dma = 1;
3618 	}
3619 	if (!found)
3620 		goto out;
3621 
3622 	/* step 2: always set host PIO timings */
3623 	ata_for_each_dev(dev, link, ENABLED) {
3624 		if (dev->pio_mode == 0xff) {
3625 			ata_dev_warn(dev, "no PIO support\n");
3626 			rc = -EINVAL;
3627 			goto out;
3628 		}
3629 
3630 		dev->xfer_mode = dev->pio_mode;
3631 		dev->xfer_shift = ATA_SHIFT_PIO;
3632 		if (ap->ops->set_piomode)
3633 			ap->ops->set_piomode(ap, dev);
3634 	}
3635 
3636 	/* step 3: set host DMA timings */
3637 	ata_for_each_dev(dev, link, ENABLED) {
3638 		if (!ata_dma_enabled(dev))
3639 			continue;
3640 
3641 		dev->xfer_mode = dev->dma_mode;
3642 		dev->xfer_shift = ata_xfer_mode2shift(dev->dma_mode);
3643 		if (ap->ops->set_dmamode)
3644 			ap->ops->set_dmamode(ap, dev);
3645 	}
3646 
3647 	/* step 4: update devices' xfer mode */
3648 	ata_for_each_dev(dev, link, ENABLED) {
3649 		rc = ata_dev_set_mode(dev);
3650 		if (rc)
3651 			goto out;
3652 	}
3653 
3654 	/* Record simplex status. If we selected DMA then the other
3655 	 * host channels are not permitted to do so.
3656 	 */
3657 	if (used_dma && (ap->host->flags & ATA_HOST_SIMPLEX))
3658 		ap->host->simplex_claimed = ap;
3659 
3660  out:
3661 	if (rc)
3662 		*r_failed_dev = dev;
3663 	return rc;
3664 }
3665 
3666 /**
3667  *	ata_wait_ready - wait for link to become ready
3668  *	@link: link to be waited on
3669  *	@deadline: deadline jiffies for the operation
3670  *	@check_ready: callback to check link readiness
3671  *
3672  *	Wait for @link to become ready.  @check_ready should return
3673  *	positive number if @link is ready, 0 if it isn't, -ENODEV if
3674  *	link doesn't seem to be occupied, other errno for other error
3675  *	conditions.
3676  *
3677  *	Transient -ENODEV conditions are allowed for
3678  *	ATA_TMOUT_FF_WAIT.
3679  *
3680  *	LOCKING:
3681  *	EH context.
3682  *
3683  *	RETURNS:
3684  *	0 if @link is ready before @deadline; otherwise, -errno.
3685  */
3686 int ata_wait_ready(struct ata_link *link, unsigned long deadline,
3687 		   int (*check_ready)(struct ata_link *link))
3688 {
3689 	unsigned long start = jiffies;
3690 	unsigned long nodev_deadline;
3691 	int warned = 0;
3692 
3693 	/* choose which 0xff timeout to use, read comment in libata.h */
3694 	if (link->ap->host->flags & ATA_HOST_PARALLEL_SCAN)
3695 		nodev_deadline = ata_deadline(start, ATA_TMOUT_FF_WAIT_LONG);
3696 	else
3697 		nodev_deadline = ata_deadline(start, ATA_TMOUT_FF_WAIT);
3698 
3699 	/* Slave readiness can't be tested separately from master.  On
3700 	 * M/S emulation configuration, this function should be called
3701 	 * only on the master and it will handle both master and slave.
3702 	 */
3703 	WARN_ON(link == link->ap->slave_link);
3704 
3705 	if (time_after(nodev_deadline, deadline))
3706 		nodev_deadline = deadline;
3707 
3708 	while (1) {
3709 		unsigned long now = jiffies;
3710 		int ready, tmp;
3711 
3712 		ready = tmp = check_ready(link);
3713 		if (ready > 0)
3714 			return 0;
3715 
3716 		/*
3717 		 * -ENODEV could be transient.  Ignore -ENODEV if link
3718 		 * is online.  Also, some SATA devices take a long
3719 		 * time to clear 0xff after reset.  Wait for
3720 		 * ATA_TMOUT_FF_WAIT[_LONG] on -ENODEV if link isn't
3721 		 * offline.
3722 		 *
3723 		 * Note that some PATA controllers (pata_ali) explode
3724 		 * if status register is read more than once when
3725 		 * there's no device attached.
3726 		 */
3727 		if (ready == -ENODEV) {
3728 			if (ata_link_online(link))
3729 				ready = 0;
3730 			else if ((link->ap->flags & ATA_FLAG_SATA) &&
3731 				 !ata_link_offline(link) &&
3732 				 time_before(now, nodev_deadline))
3733 				ready = 0;
3734 		}
3735 
3736 		if (ready)
3737 			return ready;
3738 		if (time_after(now, deadline))
3739 			return -EBUSY;
3740 
3741 		if (!warned && time_after(now, start + 5 * HZ) &&
3742 		    (deadline - now > 3 * HZ)) {
3743 			ata_link_warn(link,
3744 				"link is slow to respond, please be patient "
3745 				"(ready=%d)\n", tmp);
3746 			warned = 1;
3747 		}
3748 
3749 		ata_msleep(link->ap, 50);
3750 	}
3751 }
3752 
3753 /**
3754  *	ata_wait_after_reset - wait for link to become ready after reset
3755  *	@link: link to be waited on
3756  *	@deadline: deadline jiffies for the operation
3757  *	@check_ready: callback to check link readiness
3758  *
3759  *	Wait for @link to become ready after reset.
3760  *
3761  *	LOCKING:
3762  *	EH context.
3763  *
3764  *	RETURNS:
3765  *	0 if @link is ready before @deadline; otherwise, -errno.
3766  */
3767 int ata_wait_after_reset(struct ata_link *link, unsigned long deadline,
3768 				int (*check_ready)(struct ata_link *link))
3769 {
3770 	ata_msleep(link->ap, ATA_WAIT_AFTER_RESET);
3771 
3772 	return ata_wait_ready(link, deadline, check_ready);
3773 }
3774 
3775 /**
3776  *	sata_link_debounce - debounce SATA phy status
3777  *	@link: ATA link to debounce SATA phy status for
3778  *	@params: timing parameters { interval, duration, timeout } in msec
3779  *	@deadline: deadline jiffies for the operation
3780  *
3781  *	Make sure SStatus of @link reaches stable state, determined by
3782  *	holding the same value where DET is not 1 for @duration polled
3783  *	every @interval, before @timeout.  Timeout constraints the
3784  *	beginning of the stable state.  Because DET gets stuck at 1 on
3785  *	some controllers after hot unplugging, this functions waits
3786  *	until timeout then returns 0 if DET is stable at 1.
3787  *
3788  *	@timeout is further limited by @deadline.  The sooner of the
3789  *	two is used.
3790  *
3791  *	LOCKING:
3792  *	Kernel thread context (may sleep)
3793  *
3794  *	RETURNS:
3795  *	0 on success, -errno on failure.
3796  */
3797 int sata_link_debounce(struct ata_link *link, const unsigned long *params,
3798 		       unsigned long deadline)
3799 {
3800 	unsigned long interval = params[0];
3801 	unsigned long duration = params[1];
3802 	unsigned long last_jiffies, t;
3803 	u32 last, cur;
3804 	int rc;
3805 
3806 	t = ata_deadline(jiffies, params[2]);
3807 	if (time_before(t, deadline))
3808 		deadline = t;
3809 
3810 	if ((rc = sata_scr_read(link, SCR_STATUS, &cur)))
3811 		return rc;
3812 	cur &= 0xf;
3813 
3814 	last = cur;
3815 	last_jiffies = jiffies;
3816 
3817 	while (1) {
3818 		ata_msleep(link->ap, interval);
3819 		if ((rc = sata_scr_read(link, SCR_STATUS, &cur)))
3820 			return rc;
3821 		cur &= 0xf;
3822 
3823 		/* DET stable? */
3824 		if (cur == last) {
3825 			if (cur == 1 && time_before(jiffies, deadline))
3826 				continue;
3827 			if (time_after(jiffies,
3828 				       ata_deadline(last_jiffies, duration)))
3829 				return 0;
3830 			continue;
3831 		}
3832 
3833 		/* unstable, start over */
3834 		last = cur;
3835 		last_jiffies = jiffies;
3836 
3837 		/* Check deadline.  If debouncing failed, return
3838 		 * -EPIPE to tell upper layer to lower link speed.
3839 		 */
3840 		if (time_after(jiffies, deadline))
3841 			return -EPIPE;
3842 	}
3843 }
3844 
3845 /**
3846  *	sata_link_resume - resume SATA link
3847  *	@link: ATA link to resume SATA
3848  *	@params: timing parameters { interval, duration, timeout } in msec
3849  *	@deadline: deadline jiffies for the operation
3850  *
3851  *	Resume SATA phy @link and debounce it.
3852  *
3853  *	LOCKING:
3854  *	Kernel thread context (may sleep)
3855  *
3856  *	RETURNS:
3857  *	0 on success, -errno on failure.
3858  */
3859 int sata_link_resume(struct ata_link *link, const unsigned long *params,
3860 		     unsigned long deadline)
3861 {
3862 	int tries = ATA_LINK_RESUME_TRIES;
3863 	u32 scontrol, serror;
3864 	int rc;
3865 
3866 	if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3867 		return rc;
3868 
3869 	/*
3870 	 * Writes to SControl sometimes get ignored under certain
3871 	 * controllers (ata_piix SIDPR).  Make sure DET actually is
3872 	 * cleared.
3873 	 */
3874 	do {
3875 		scontrol = (scontrol & 0x0f0) | 0x300;
3876 		if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
3877 			return rc;
3878 		/*
3879 		 * Some PHYs react badly if SStatus is pounded
3880 		 * immediately after resuming.  Delay 200ms before
3881 		 * debouncing.
3882 		 */
3883 		if (!(link->flags & ATA_LFLAG_NO_DB_DELAY))
3884 			ata_msleep(link->ap, 200);
3885 
3886 		/* is SControl restored correctly? */
3887 		if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3888 			return rc;
3889 	} while ((scontrol & 0xf0f) != 0x300 && --tries);
3890 
3891 	if ((scontrol & 0xf0f) != 0x300) {
3892 		ata_link_warn(link, "failed to resume link (SControl %X)\n",
3893 			     scontrol);
3894 		return 0;
3895 	}
3896 
3897 	if (tries < ATA_LINK_RESUME_TRIES)
3898 		ata_link_warn(link, "link resume succeeded after %d retries\n",
3899 			      ATA_LINK_RESUME_TRIES - tries);
3900 
3901 	if ((rc = sata_link_debounce(link, params, deadline)))
3902 		return rc;
3903 
3904 	/* clear SError, some PHYs require this even for SRST to work */
3905 	if (!(rc = sata_scr_read(link, SCR_ERROR, &serror)))
3906 		rc = sata_scr_write(link, SCR_ERROR, serror);
3907 
3908 	return rc != -EINVAL ? rc : 0;
3909 }
3910 
3911 /**
3912  *	sata_link_scr_lpm - manipulate SControl IPM and SPM fields
3913  *	@link: ATA link to manipulate SControl for
3914  *	@policy: LPM policy to configure
3915  *	@spm_wakeup: initiate LPM transition to active state
3916  *
3917  *	Manipulate the IPM field of the SControl register of @link
3918  *	according to @policy.  If @policy is ATA_LPM_MAX_POWER and
3919  *	@spm_wakeup is %true, the SPM field is manipulated to wake up
3920  *	the link.  This function also clears PHYRDY_CHG before
3921  *	returning.
3922  *
3923  *	LOCKING:
3924  *	EH context.
3925  *
3926  *	RETURNS:
3927  *	0 on success, -errno otherwise.
3928  */
3929 int sata_link_scr_lpm(struct ata_link *link, enum ata_lpm_policy policy,
3930 		      bool spm_wakeup)
3931 {
3932 	struct ata_eh_context *ehc = &link->eh_context;
3933 	bool woken_up = false;
3934 	u32 scontrol;
3935 	int rc;
3936 
3937 	rc = sata_scr_read(link, SCR_CONTROL, &scontrol);
3938 	if (rc)
3939 		return rc;
3940 
3941 	switch (policy) {
3942 	case ATA_LPM_MAX_POWER:
3943 		/* disable all LPM transitions */
3944 		scontrol |= (0x7 << 8);
3945 		/* initiate transition to active state */
3946 		if (spm_wakeup) {
3947 			scontrol |= (0x4 << 12);
3948 			woken_up = true;
3949 		}
3950 		break;
3951 	case ATA_LPM_MED_POWER:
3952 		/* allow LPM to PARTIAL */
3953 		scontrol &= ~(0x1 << 8);
3954 		scontrol |= (0x6 << 8);
3955 		break;
3956 	case ATA_LPM_MED_POWER_WITH_DIPM:
3957 	case ATA_LPM_MIN_POWER_WITH_PARTIAL:
3958 	case ATA_LPM_MIN_POWER:
3959 		if (ata_link_nr_enabled(link) > 0)
3960 			/* no restrictions on LPM transitions */
3961 			scontrol &= ~(0x7 << 8);
3962 		else {
3963 			/* empty port, power off */
3964 			scontrol &= ~0xf;
3965 			scontrol |= (0x1 << 2);
3966 		}
3967 		break;
3968 	default:
3969 		WARN_ON(1);
3970 	}
3971 
3972 	rc = sata_scr_write(link, SCR_CONTROL, scontrol);
3973 	if (rc)
3974 		return rc;
3975 
3976 	/* give the link time to transit out of LPM state */
3977 	if (woken_up)
3978 		msleep(10);
3979 
3980 	/* clear PHYRDY_CHG from SError */
3981 	ehc->i.serror &= ~SERR_PHYRDY_CHG;
3982 	return sata_scr_write(link, SCR_ERROR, SERR_PHYRDY_CHG);
3983 }
3984 
3985 /**
3986  *	ata_std_prereset - prepare for reset
3987  *	@link: ATA link to be reset
3988  *	@deadline: deadline jiffies for the operation
3989  *
3990  *	@link is about to be reset.  Initialize it.  Failure from
3991  *	prereset makes libata abort whole reset sequence and give up
3992  *	that port, so prereset should be best-effort.  It does its
3993  *	best to prepare for reset sequence but if things go wrong, it
3994  *	should just whine, not fail.
3995  *
3996  *	LOCKING:
3997  *	Kernel thread context (may sleep)
3998  *
3999  *	RETURNS:
4000  *	0 on success, -errno otherwise.
4001  */
4002 int ata_std_prereset(struct ata_link *link, unsigned long deadline)
4003 {
4004 	struct ata_port *ap = link->ap;
4005 	struct ata_eh_context *ehc = &link->eh_context;
4006 	const unsigned long *timing = sata_ehc_deb_timing(ehc);
4007 	int rc;
4008 
4009 	/* if we're about to do hardreset, nothing more to do */
4010 	if (ehc->i.action & ATA_EH_HARDRESET)
4011 		return 0;
4012 
4013 	/* if SATA, resume link */
4014 	if (ap->flags & ATA_FLAG_SATA) {
4015 		rc = sata_link_resume(link, timing, deadline);
4016 		/* whine about phy resume failure but proceed */
4017 		if (rc && rc != -EOPNOTSUPP)
4018 			ata_link_warn(link,
4019 				      "failed to resume link for reset (errno=%d)\n",
4020 				      rc);
4021 	}
4022 
4023 	/* no point in trying softreset on offline link */
4024 	if (ata_phys_link_offline(link))
4025 		ehc->i.action &= ~ATA_EH_SOFTRESET;
4026 
4027 	return 0;
4028 }
4029 
4030 /**
4031  *	sata_link_hardreset - reset link via SATA phy reset
4032  *	@link: link to reset
4033  *	@timing: timing parameters { interval, duration, timeout } in msec
4034  *	@deadline: deadline jiffies for the operation
4035  *	@online: optional out parameter indicating link onlineness
4036  *	@check_ready: optional callback to check link readiness
4037  *
4038  *	SATA phy-reset @link using DET bits of SControl register.
4039  *	After hardreset, link readiness is waited upon using
4040  *	ata_wait_ready() if @check_ready is specified.  LLDs are
4041  *	allowed to not specify @check_ready and wait itself after this
4042  *	function returns.  Device classification is LLD's
4043  *	responsibility.
4044  *
4045  *	*@online is set to one iff reset succeeded and @link is online
4046  *	after reset.
4047  *
4048  *	LOCKING:
4049  *	Kernel thread context (may sleep)
4050  *
4051  *	RETURNS:
4052  *	0 on success, -errno otherwise.
4053  */
4054 int sata_link_hardreset(struct ata_link *link, const unsigned long *timing,
4055 			unsigned long deadline,
4056 			bool *online, int (*check_ready)(struct ata_link *))
4057 {
4058 	u32 scontrol;
4059 	int rc;
4060 
4061 	DPRINTK("ENTER\n");
4062 
4063 	if (online)
4064 		*online = false;
4065 
4066 	if (sata_set_spd_needed(link)) {
4067 		/* SATA spec says nothing about how to reconfigure
4068 		 * spd.  To be on the safe side, turn off phy during
4069 		 * reconfiguration.  This works for at least ICH7 AHCI
4070 		 * and Sil3124.
4071 		 */
4072 		if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
4073 			goto out;
4074 
4075 		scontrol = (scontrol & 0x0f0) | 0x304;
4076 
4077 		if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
4078 			goto out;
4079 
4080 		sata_set_spd(link);
4081 	}
4082 
4083 	/* issue phy wake/reset */
4084 	if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
4085 		goto out;
4086 
4087 	scontrol = (scontrol & 0x0f0) | 0x301;
4088 
4089 	if ((rc = sata_scr_write_flush(link, SCR_CONTROL, scontrol)))
4090 		goto out;
4091 
4092 	/* Couldn't find anything in SATA I/II specs, but AHCI-1.1
4093 	 * 10.4.2 says at least 1 ms.
4094 	 */
4095 	ata_msleep(link->ap, 1);
4096 
4097 	/* bring link back */
4098 	rc = sata_link_resume(link, timing, deadline);
4099 	if (rc)
4100 		goto out;
4101 	/* if link is offline nothing more to do */
4102 	if (ata_phys_link_offline(link))
4103 		goto out;
4104 
4105 	/* Link is online.  From this point, -ENODEV too is an error. */
4106 	if (online)
4107 		*online = true;
4108 
4109 	if (sata_pmp_supported(link->ap) && ata_is_host_link(link)) {
4110 		/* If PMP is supported, we have to do follow-up SRST.
4111 		 * Some PMPs don't send D2H Reg FIS after hardreset if
4112 		 * the first port is empty.  Wait only for
4113 		 * ATA_TMOUT_PMP_SRST_WAIT.
4114 		 */
4115 		if (check_ready) {
4116 			unsigned long pmp_deadline;
4117 
4118 			pmp_deadline = ata_deadline(jiffies,
4119 						    ATA_TMOUT_PMP_SRST_WAIT);
4120 			if (time_after(pmp_deadline, deadline))
4121 				pmp_deadline = deadline;
4122 			ata_wait_ready(link, pmp_deadline, check_ready);
4123 		}
4124 		rc = -EAGAIN;
4125 		goto out;
4126 	}
4127 
4128 	rc = 0;
4129 	if (check_ready)
4130 		rc = ata_wait_ready(link, deadline, check_ready);
4131  out:
4132 	if (rc && rc != -EAGAIN) {
4133 		/* online is set iff link is online && reset succeeded */
4134 		if (online)
4135 			*online = false;
4136 		ata_link_err(link, "COMRESET failed (errno=%d)\n", rc);
4137 	}
4138 	DPRINTK("EXIT, rc=%d\n", rc);
4139 	return rc;
4140 }
4141 
4142 /**
4143  *	sata_std_hardreset - COMRESET w/o waiting or classification
4144  *	@link: link to reset
4145  *	@class: resulting class of attached device
4146  *	@deadline: deadline jiffies for the operation
4147  *
4148  *	Standard SATA COMRESET w/o waiting or classification.
4149  *
4150  *	LOCKING:
4151  *	Kernel thread context (may sleep)
4152  *
4153  *	RETURNS:
4154  *	0 if link offline, -EAGAIN if link online, -errno on errors.
4155  */
4156 int sata_std_hardreset(struct ata_link *link, unsigned int *class,
4157 		       unsigned long deadline)
4158 {
4159 	const unsigned long *timing = sata_ehc_deb_timing(&link->eh_context);
4160 	bool online;
4161 	int rc;
4162 
4163 	/* do hardreset */
4164 	rc = sata_link_hardreset(link, timing, deadline, &online, NULL);
4165 	return online ? -EAGAIN : rc;
4166 }
4167 
4168 /**
4169  *	ata_std_postreset - standard postreset callback
4170  *	@link: the target ata_link
4171  *	@classes: classes of attached devices
4172  *
4173  *	This function is invoked after a successful reset.  Note that
4174  *	the device might have been reset more than once using
4175  *	different reset methods before postreset is invoked.
4176  *
4177  *	LOCKING:
4178  *	Kernel thread context (may sleep)
4179  */
4180 void ata_std_postreset(struct ata_link *link, unsigned int *classes)
4181 {
4182 	u32 serror;
4183 
4184 	DPRINTK("ENTER\n");
4185 
4186 	/* reset complete, clear SError */
4187 	if (!sata_scr_read(link, SCR_ERROR, &serror))
4188 		sata_scr_write(link, SCR_ERROR, serror);
4189 
4190 	/* print link status */
4191 	sata_print_link_status(link);
4192 
4193 	DPRINTK("EXIT\n");
4194 }
4195 
4196 /**
4197  *	ata_dev_same_device - Determine whether new ID matches configured device
4198  *	@dev: device to compare against
4199  *	@new_class: class of the new device
4200  *	@new_id: IDENTIFY page of the new device
4201  *
4202  *	Compare @new_class and @new_id against @dev and determine
4203  *	whether @dev is the device indicated by @new_class and
4204  *	@new_id.
4205  *
4206  *	LOCKING:
4207  *	None.
4208  *
4209  *	RETURNS:
4210  *	1 if @dev matches @new_class and @new_id, 0 otherwise.
4211  */
4212 static int ata_dev_same_device(struct ata_device *dev, unsigned int new_class,
4213 			       const u16 *new_id)
4214 {
4215 	const u16 *old_id = dev->id;
4216 	unsigned char model[2][ATA_ID_PROD_LEN + 1];
4217 	unsigned char serial[2][ATA_ID_SERNO_LEN + 1];
4218 
4219 	if (dev->class != new_class) {
4220 		ata_dev_info(dev, "class mismatch %d != %d\n",
4221 			     dev->class, new_class);
4222 		return 0;
4223 	}
4224 
4225 	ata_id_c_string(old_id, model[0], ATA_ID_PROD, sizeof(model[0]));
4226 	ata_id_c_string(new_id, model[1], ATA_ID_PROD, sizeof(model[1]));
4227 	ata_id_c_string(old_id, serial[0], ATA_ID_SERNO, sizeof(serial[0]));
4228 	ata_id_c_string(new_id, serial[1], ATA_ID_SERNO, sizeof(serial[1]));
4229 
4230 	if (strcmp(model[0], model[1])) {
4231 		ata_dev_info(dev, "model number mismatch '%s' != '%s'\n",
4232 			     model[0], model[1]);
4233 		return 0;
4234 	}
4235 
4236 	if (strcmp(serial[0], serial[1])) {
4237 		ata_dev_info(dev, "serial number mismatch '%s' != '%s'\n",
4238 			     serial[0], serial[1]);
4239 		return 0;
4240 	}
4241 
4242 	return 1;
4243 }
4244 
4245 /**
4246  *	ata_dev_reread_id - Re-read IDENTIFY data
4247  *	@dev: target ATA device
4248  *	@readid_flags: read ID flags
4249  *
4250  *	Re-read IDENTIFY page and make sure @dev is still attached to
4251  *	the port.
4252  *
4253  *	LOCKING:
4254  *	Kernel thread context (may sleep)
4255  *
4256  *	RETURNS:
4257  *	0 on success, negative errno otherwise
4258  */
4259 int ata_dev_reread_id(struct ata_device *dev, unsigned int readid_flags)
4260 {
4261 	unsigned int class = dev->class;
4262 	u16 *id = (void *)dev->link->ap->sector_buf;
4263 	int rc;
4264 
4265 	/* read ID data */
4266 	rc = ata_dev_read_id(dev, &class, readid_flags, id);
4267 	if (rc)
4268 		return rc;
4269 
4270 	/* is the device still there? */
4271 	if (!ata_dev_same_device(dev, class, id))
4272 		return -ENODEV;
4273 
4274 	memcpy(dev->id, id, sizeof(id[0]) * ATA_ID_WORDS);
4275 	return 0;
4276 }
4277 
4278 /**
4279  *	ata_dev_revalidate - Revalidate ATA device
4280  *	@dev: device to revalidate
4281  *	@new_class: new class code
4282  *	@readid_flags: read ID flags
4283  *
4284  *	Re-read IDENTIFY page, make sure @dev is still attached to the
4285  *	port and reconfigure it according to the new IDENTIFY page.
4286  *
4287  *	LOCKING:
4288  *	Kernel thread context (may sleep)
4289  *
4290  *	RETURNS:
4291  *	0 on success, negative errno otherwise
4292  */
4293 int ata_dev_revalidate(struct ata_device *dev, unsigned int new_class,
4294 		       unsigned int readid_flags)
4295 {
4296 	u64 n_sectors = dev->n_sectors;
4297 	u64 n_native_sectors = dev->n_native_sectors;
4298 	int rc;
4299 
4300 	if (!ata_dev_enabled(dev))
4301 		return -ENODEV;
4302 
4303 	/* fail early if !ATA && !ATAPI to avoid issuing [P]IDENTIFY to PMP */
4304 	if (ata_class_enabled(new_class) &&
4305 	    new_class != ATA_DEV_ATA &&
4306 	    new_class != ATA_DEV_ATAPI &&
4307 	    new_class != ATA_DEV_ZAC &&
4308 	    new_class != ATA_DEV_SEMB) {
4309 		ata_dev_info(dev, "class mismatch %u != %u\n",
4310 			     dev->class, new_class);
4311 		rc = -ENODEV;
4312 		goto fail;
4313 	}
4314 
4315 	/* re-read ID */
4316 	rc = ata_dev_reread_id(dev, readid_flags);
4317 	if (rc)
4318 		goto fail;
4319 
4320 	/* configure device according to the new ID */
4321 	rc = ata_dev_configure(dev);
4322 	if (rc)
4323 		goto fail;
4324 
4325 	/* verify n_sectors hasn't changed */
4326 	if (dev->class != ATA_DEV_ATA || !n_sectors ||
4327 	    dev->n_sectors == n_sectors)
4328 		return 0;
4329 
4330 	/* n_sectors has changed */
4331 	ata_dev_warn(dev, "n_sectors mismatch %llu != %llu\n",
4332 		     (unsigned long long)n_sectors,
4333 		     (unsigned long long)dev->n_sectors);
4334 
4335 	/*
4336 	 * Something could have caused HPA to be unlocked
4337 	 * involuntarily.  If n_native_sectors hasn't changed and the
4338 	 * new size matches it, keep the device.
4339 	 */
4340 	if (dev->n_native_sectors == n_native_sectors &&
4341 	    dev->n_sectors > n_sectors && dev->n_sectors == n_native_sectors) {
4342 		ata_dev_warn(dev,
4343 			     "new n_sectors matches native, probably "
4344 			     "late HPA unlock, n_sectors updated\n");
4345 		/* use the larger n_sectors */
4346 		return 0;
4347 	}
4348 
4349 	/*
4350 	 * Some BIOSes boot w/o HPA but resume w/ HPA locked.  Try
4351 	 * unlocking HPA in those cases.
4352 	 *
4353 	 * https://bugzilla.kernel.org/show_bug.cgi?id=15396
4354 	 */
4355 	if (dev->n_native_sectors == n_native_sectors &&
4356 	    dev->n_sectors < n_sectors && n_sectors == n_native_sectors &&
4357 	    !(dev->horkage & ATA_HORKAGE_BROKEN_HPA)) {
4358 		ata_dev_warn(dev,
4359 			     "old n_sectors matches native, probably "
4360 			     "late HPA lock, will try to unlock HPA\n");
4361 		/* try unlocking HPA */
4362 		dev->flags |= ATA_DFLAG_UNLOCK_HPA;
4363 		rc = -EIO;
4364 	} else
4365 		rc = -ENODEV;
4366 
4367 	/* restore original n_[native_]sectors and fail */
4368 	dev->n_native_sectors = n_native_sectors;
4369 	dev->n_sectors = n_sectors;
4370  fail:
4371 	ata_dev_err(dev, "revalidation failed (errno=%d)\n", rc);
4372 	return rc;
4373 }
4374 
4375 struct ata_blacklist_entry {
4376 	const char *model_num;
4377 	const char *model_rev;
4378 	unsigned long horkage;
4379 };
4380 
4381 static const struct ata_blacklist_entry ata_device_blacklist [] = {
4382 	/* Devices with DMA related problems under Linux */
4383 	{ "WDC AC11000H",	NULL,		ATA_HORKAGE_NODMA },
4384 	{ "WDC AC22100H",	NULL,		ATA_HORKAGE_NODMA },
4385 	{ "WDC AC32500H",	NULL,		ATA_HORKAGE_NODMA },
4386 	{ "WDC AC33100H",	NULL,		ATA_HORKAGE_NODMA },
4387 	{ "WDC AC31600H",	NULL,		ATA_HORKAGE_NODMA },
4388 	{ "WDC AC32100H",	"24.09P07",	ATA_HORKAGE_NODMA },
4389 	{ "WDC AC23200L",	"21.10N21",	ATA_HORKAGE_NODMA },
4390 	{ "Compaq CRD-8241B", 	NULL,		ATA_HORKAGE_NODMA },
4391 	{ "CRD-8400B",		NULL, 		ATA_HORKAGE_NODMA },
4392 	{ "CRD-848[02]B",	NULL,		ATA_HORKAGE_NODMA },
4393 	{ "CRD-84",		NULL,		ATA_HORKAGE_NODMA },
4394 	{ "SanDisk SDP3B",	NULL,		ATA_HORKAGE_NODMA },
4395 	{ "SanDisk SDP3B-64",	NULL,		ATA_HORKAGE_NODMA },
4396 	{ "SANYO CD-ROM CRD",	NULL,		ATA_HORKAGE_NODMA },
4397 	{ "HITACHI CDR-8",	NULL,		ATA_HORKAGE_NODMA },
4398 	{ "HITACHI CDR-8[34]35",NULL,		ATA_HORKAGE_NODMA },
4399 	{ "Toshiba CD-ROM XM-6202B", NULL,	ATA_HORKAGE_NODMA },
4400 	{ "TOSHIBA CD-ROM XM-1702BC", NULL,	ATA_HORKAGE_NODMA },
4401 	{ "CD-532E-A", 		NULL,		ATA_HORKAGE_NODMA },
4402 	{ "E-IDE CD-ROM CR-840",NULL,		ATA_HORKAGE_NODMA },
4403 	{ "CD-ROM Drive/F5A",	NULL,		ATA_HORKAGE_NODMA },
4404 	{ "WPI CDD-820", 	NULL,		ATA_HORKAGE_NODMA },
4405 	{ "SAMSUNG CD-ROM SC-148C", NULL,	ATA_HORKAGE_NODMA },
4406 	{ "SAMSUNG CD-ROM SC",	NULL,		ATA_HORKAGE_NODMA },
4407 	{ "ATAPI CD-ROM DRIVE 40X MAXIMUM",NULL,ATA_HORKAGE_NODMA },
4408 	{ "_NEC DV5800A", 	NULL,		ATA_HORKAGE_NODMA },
4409 	{ "SAMSUNG CD-ROM SN-124", "N001",	ATA_HORKAGE_NODMA },
4410 	{ "Seagate STT20000A", NULL,		ATA_HORKAGE_NODMA },
4411 	{ " 2GB ATA Flash Disk", "ADMA428M",	ATA_HORKAGE_NODMA },
4412 	{ "VRFDFC22048UCHC-TE*", NULL,		ATA_HORKAGE_NODMA },
4413 	/* Odd clown on sil3726/4726 PMPs */
4414 	{ "Config  Disk",	NULL,		ATA_HORKAGE_DISABLE },
4415 
4416 	/* Weird ATAPI devices */
4417 	{ "TORiSAN DVD-ROM DRD-N216", NULL,	ATA_HORKAGE_MAX_SEC_128 },
4418 	{ "QUANTUM DAT    DAT72-000", NULL,	ATA_HORKAGE_ATAPI_MOD16_DMA },
4419 	{ "Slimtype DVD A  DS8A8SH", NULL,	ATA_HORKAGE_MAX_SEC_LBA48 },
4420 	{ "Slimtype DVD A  DS8A9SH", NULL,	ATA_HORKAGE_MAX_SEC_LBA48 },
4421 
4422 	/*
4423 	 * Causes silent data corruption with higher max sects.
4424 	 * http://lkml.kernel.org/g/x49wpy40ysk.fsf@segfault.boston.devel.redhat.com
4425 	 */
4426 	{ "ST380013AS",		"3.20",		ATA_HORKAGE_MAX_SEC_1024 },
4427 
4428 	/*
4429 	 * These devices time out with higher max sects.
4430 	 * https://bugzilla.kernel.org/show_bug.cgi?id=121671
4431 	 */
4432 	{ "LITEON CX1-JB*-HP",	NULL,		ATA_HORKAGE_MAX_SEC_1024 },
4433 	{ "LITEON EP1-*",	NULL,		ATA_HORKAGE_MAX_SEC_1024 },
4434 
4435 	/* Devices we expect to fail diagnostics */
4436 
4437 	/* Devices where NCQ should be avoided */
4438 	/* NCQ is slow */
4439 	{ "WDC WD740ADFD-00",	NULL,		ATA_HORKAGE_NONCQ },
4440 	{ "WDC WD740ADFD-00NLR1", NULL,		ATA_HORKAGE_NONCQ, },
4441 	/* http://thread.gmane.org/gmane.linux.ide/14907 */
4442 	{ "FUJITSU MHT2060BH",	NULL,		ATA_HORKAGE_NONCQ },
4443 	/* NCQ is broken */
4444 	{ "Maxtor *",		"BANC*",	ATA_HORKAGE_NONCQ },
4445 	{ "Maxtor 7V300F0",	"VA111630",	ATA_HORKAGE_NONCQ },
4446 	{ "ST380817AS",		"3.42",		ATA_HORKAGE_NONCQ },
4447 	{ "ST3160023AS",	"3.42",		ATA_HORKAGE_NONCQ },
4448 	{ "OCZ CORE_SSD",	"02.10104",	ATA_HORKAGE_NONCQ },
4449 
4450 	/* Seagate NCQ + FLUSH CACHE firmware bug */
4451 	{ "ST31500341AS",	"SD1[5-9]",	ATA_HORKAGE_NONCQ |
4452 						ATA_HORKAGE_FIRMWARE_WARN },
4453 
4454 	{ "ST31000333AS",	"SD1[5-9]",	ATA_HORKAGE_NONCQ |
4455 						ATA_HORKAGE_FIRMWARE_WARN },
4456 
4457 	{ "ST3640[36]23AS",	"SD1[5-9]",	ATA_HORKAGE_NONCQ |
4458 						ATA_HORKAGE_FIRMWARE_WARN },
4459 
4460 	{ "ST3320[68]13AS",	"SD1[5-9]",	ATA_HORKAGE_NONCQ |
4461 						ATA_HORKAGE_FIRMWARE_WARN },
4462 
4463 	/* drives which fail FPDMA_AA activation (some may freeze afterwards) */
4464 	{ "ST1000LM024 HN-M101MBB", "2AR10001",	ATA_HORKAGE_BROKEN_FPDMA_AA },
4465 	{ "ST1000LM024 HN-M101MBB", "2BA30001",	ATA_HORKAGE_BROKEN_FPDMA_AA },
4466 	{ "VB0250EAVER",	"HPG7",		ATA_HORKAGE_BROKEN_FPDMA_AA },
4467 
4468 	/* Blacklist entries taken from Silicon Image 3124/3132
4469 	   Windows driver .inf file - also several Linux problem reports */
4470 	{ "HTS541060G9SA00",    "MB3OC60D",     ATA_HORKAGE_NONCQ, },
4471 	{ "HTS541080G9SA00",    "MB4OC60D",     ATA_HORKAGE_NONCQ, },
4472 	{ "HTS541010G9SA00",    "MBZOC60D",     ATA_HORKAGE_NONCQ, },
4473 
4474 	/* https://bugzilla.kernel.org/show_bug.cgi?id=15573 */
4475 	{ "C300-CTFDDAC128MAG",	"0001",		ATA_HORKAGE_NONCQ, },
4476 
4477 	/* Some Sandisk SSDs lock up hard with NCQ enabled.  Reported on
4478 	   SD7SN6S256G and SD8SN8U256G */
4479 	{ "SanDisk SD[78]SN*G",	NULL,		ATA_HORKAGE_NONCQ, },
4480 
4481 	/* devices which puke on READ_NATIVE_MAX */
4482 	{ "HDS724040KLSA80",	"KFAOA20N",	ATA_HORKAGE_BROKEN_HPA, },
4483 	{ "WDC WD3200JD-00KLB0", "WD-WCAMR1130137", ATA_HORKAGE_BROKEN_HPA },
4484 	{ "WDC WD2500JD-00HBB0", "WD-WMAL71490727", ATA_HORKAGE_BROKEN_HPA },
4485 	{ "MAXTOR 6L080L4",	"A93.0500",	ATA_HORKAGE_BROKEN_HPA },
4486 
4487 	/* this one allows HPA unlocking but fails IOs on the area */
4488 	{ "OCZ-VERTEX",		    "1.30",	ATA_HORKAGE_BROKEN_HPA },
4489 
4490 	/* Devices which report 1 sector over size HPA */
4491 	{ "ST340823A",		NULL,		ATA_HORKAGE_HPA_SIZE, },
4492 	{ "ST320413A",		NULL,		ATA_HORKAGE_HPA_SIZE, },
4493 	{ "ST310211A",		NULL,		ATA_HORKAGE_HPA_SIZE, },
4494 
4495 	/* Devices which get the IVB wrong */
4496 	{ "QUANTUM FIREBALLlct10 05", "A03.0900", ATA_HORKAGE_IVB, },
4497 	/* Maybe we should just blacklist TSSTcorp... */
4498 	{ "TSSTcorp CDDVDW SH-S202[HJN]", "SB0[01]",  ATA_HORKAGE_IVB, },
4499 
4500 	/* Devices that do not need bridging limits applied */
4501 	{ "MTRON MSP-SATA*",		NULL,	ATA_HORKAGE_BRIDGE_OK, },
4502 	{ "BUFFALO HD-QSU2/R5",		NULL,	ATA_HORKAGE_BRIDGE_OK, },
4503 
4504 	/* Devices which aren't very happy with higher link speeds */
4505 	{ "WD My Book",			NULL,	ATA_HORKAGE_1_5_GBPS, },
4506 	{ "Seagate FreeAgent GoFlex",	NULL,	ATA_HORKAGE_1_5_GBPS, },
4507 
4508 	/*
4509 	 * Devices which choke on SETXFER.  Applies only if both the
4510 	 * device and controller are SATA.
4511 	 */
4512 	{ "PIONEER DVD-RW  DVRTD08",	NULL,	ATA_HORKAGE_NOSETXFER },
4513 	{ "PIONEER DVD-RW  DVRTD08A",	NULL,	ATA_HORKAGE_NOSETXFER },
4514 	{ "PIONEER DVD-RW  DVR-215",	NULL,	ATA_HORKAGE_NOSETXFER },
4515 	{ "PIONEER DVD-RW  DVR-212D",	NULL,	ATA_HORKAGE_NOSETXFER },
4516 	{ "PIONEER DVD-RW  DVR-216D",	NULL,	ATA_HORKAGE_NOSETXFER },
4517 
4518 	/* Crucial BX100 SSD 500GB has broken LPM support */
4519 	{ "CT500BX100SSD1",		NULL,	ATA_HORKAGE_NOLPM },
4520 
4521 	/* 512GB MX100 with MU01 firmware has both queued TRIM and LPM issues */
4522 	{ "Crucial_CT512MX100*",	"MU01",	ATA_HORKAGE_NO_NCQ_TRIM |
4523 						ATA_HORKAGE_ZERO_AFTER_TRIM |
4524 						ATA_HORKAGE_NOLPM, },
4525 	/* 512GB MX100 with newer firmware has only LPM issues */
4526 	{ "Crucial_CT512MX100*",	NULL,	ATA_HORKAGE_ZERO_AFTER_TRIM |
4527 						ATA_HORKAGE_NOLPM, },
4528 
4529 	/* 480GB+ M500 SSDs have both queued TRIM and LPM issues */
4530 	{ "Crucial_CT480M500*",		NULL,	ATA_HORKAGE_NO_NCQ_TRIM |
4531 						ATA_HORKAGE_ZERO_AFTER_TRIM |
4532 						ATA_HORKAGE_NOLPM, },
4533 	{ "Crucial_CT960M500*",		NULL,	ATA_HORKAGE_NO_NCQ_TRIM |
4534 						ATA_HORKAGE_ZERO_AFTER_TRIM |
4535 						ATA_HORKAGE_NOLPM, },
4536 
4537 	/* These specific Samsung models/firmware-revs do not handle LPM well */
4538 	{ "SAMSUNG MZMPC128HBFU-000MV", "CXM14M1Q", ATA_HORKAGE_NOLPM, },
4539 	{ "SAMSUNG SSD PM830 mSATA *",  "CXM13D1Q", ATA_HORKAGE_NOLPM, },
4540 	{ "SAMSUNG MZ7TD256HAFV-000L9", NULL,       ATA_HORKAGE_NOLPM, },
4541 	{ "SAMSUNG MZ7TE512HMHP-000L1", "EXT06L0Q", ATA_HORKAGE_NOLPM, },
4542 
4543 	/* devices that don't properly handle queued TRIM commands */
4544 	{ "Micron_M500IT_*",		"MU01",	ATA_HORKAGE_NO_NCQ_TRIM |
4545 						ATA_HORKAGE_ZERO_AFTER_TRIM, },
4546 	{ "Micron_M500_*",		NULL,	ATA_HORKAGE_NO_NCQ_TRIM |
4547 						ATA_HORKAGE_ZERO_AFTER_TRIM, },
4548 	{ "Crucial_CT*M500*",		NULL,	ATA_HORKAGE_NO_NCQ_TRIM |
4549 						ATA_HORKAGE_ZERO_AFTER_TRIM, },
4550 	{ "Micron_M5[15]0_*",		"MU01",	ATA_HORKAGE_NO_NCQ_TRIM |
4551 						ATA_HORKAGE_ZERO_AFTER_TRIM, },
4552 	{ "Crucial_CT*M550*",		"MU01",	ATA_HORKAGE_NO_NCQ_TRIM |
4553 						ATA_HORKAGE_ZERO_AFTER_TRIM, },
4554 	{ "Crucial_CT*MX100*",		"MU01",	ATA_HORKAGE_NO_NCQ_TRIM |
4555 						ATA_HORKAGE_ZERO_AFTER_TRIM, },
4556 	{ "Samsung SSD 840*",		NULL,	ATA_HORKAGE_NO_NCQ_TRIM |
4557 						ATA_HORKAGE_ZERO_AFTER_TRIM, },
4558 	{ "Samsung SSD 850*",		NULL,	ATA_HORKAGE_NO_NCQ_TRIM |
4559 						ATA_HORKAGE_ZERO_AFTER_TRIM, },
4560 	{ "FCCT*M500*",			NULL,	ATA_HORKAGE_NO_NCQ_TRIM |
4561 						ATA_HORKAGE_ZERO_AFTER_TRIM, },
4562 
4563 	/* devices that don't properly handle TRIM commands */
4564 	{ "SuperSSpeed S238*",		NULL,	ATA_HORKAGE_NOTRIM, },
4565 
4566 	/*
4567 	 * As defined, the DRAT (Deterministic Read After Trim) and RZAT
4568 	 * (Return Zero After Trim) flags in the ATA Command Set are
4569 	 * unreliable in the sense that they only define what happens if
4570 	 * the device successfully executed the DSM TRIM command. TRIM
4571 	 * is only advisory, however, and the device is free to silently
4572 	 * ignore all or parts of the request.
4573 	 *
4574 	 * Whitelist drives that are known to reliably return zeroes
4575 	 * after TRIM.
4576 	 */
4577 
4578 	/*
4579 	 * The intel 510 drive has buggy DRAT/RZAT. Explicitly exclude
4580 	 * that model before whitelisting all other intel SSDs.
4581 	 */
4582 	{ "INTEL*SSDSC2MH*",		NULL,	0, },
4583 
4584 	{ "Micron*",			NULL,	ATA_HORKAGE_ZERO_AFTER_TRIM, },
4585 	{ "Crucial*",			NULL,	ATA_HORKAGE_ZERO_AFTER_TRIM, },
4586 	{ "INTEL*SSD*", 		NULL,	ATA_HORKAGE_ZERO_AFTER_TRIM, },
4587 	{ "SSD*INTEL*",			NULL,	ATA_HORKAGE_ZERO_AFTER_TRIM, },
4588 	{ "Samsung*SSD*",		NULL,	ATA_HORKAGE_ZERO_AFTER_TRIM, },
4589 	{ "SAMSUNG*SSD*",		NULL,	ATA_HORKAGE_ZERO_AFTER_TRIM, },
4590 	{ "SAMSUNG*MZ7KM*",		NULL,	ATA_HORKAGE_ZERO_AFTER_TRIM, },
4591 	{ "ST[1248][0248]0[FH]*",	NULL,	ATA_HORKAGE_ZERO_AFTER_TRIM, },
4592 
4593 	/*
4594 	 * Some WD SATA-I drives spin up and down erratically when the link
4595 	 * is put into the slumber mode.  We don't have full list of the
4596 	 * affected devices.  Disable LPM if the device matches one of the
4597 	 * known prefixes and is SATA-1.  As a side effect LPM partial is
4598 	 * lost too.
4599 	 *
4600 	 * https://bugzilla.kernel.org/show_bug.cgi?id=57211
4601 	 */
4602 	{ "WDC WD800JD-*",		NULL,	ATA_HORKAGE_WD_BROKEN_LPM },
4603 	{ "WDC WD1200JD-*",		NULL,	ATA_HORKAGE_WD_BROKEN_LPM },
4604 	{ "WDC WD1600JD-*",		NULL,	ATA_HORKAGE_WD_BROKEN_LPM },
4605 	{ "WDC WD2000JD-*",		NULL,	ATA_HORKAGE_WD_BROKEN_LPM },
4606 	{ "WDC WD2500JD-*",		NULL,	ATA_HORKAGE_WD_BROKEN_LPM },
4607 	{ "WDC WD3000JD-*",		NULL,	ATA_HORKAGE_WD_BROKEN_LPM },
4608 	{ "WDC WD3200JD-*",		NULL,	ATA_HORKAGE_WD_BROKEN_LPM },
4609 
4610 	/* End Marker */
4611 	{ }
4612 };
4613 
4614 static unsigned long ata_dev_blacklisted(const struct ata_device *dev)
4615 {
4616 	unsigned char model_num[ATA_ID_PROD_LEN + 1];
4617 	unsigned char model_rev[ATA_ID_FW_REV_LEN + 1];
4618 	const struct ata_blacklist_entry *ad = ata_device_blacklist;
4619 
4620 	ata_id_c_string(dev->id, model_num, ATA_ID_PROD, sizeof(model_num));
4621 	ata_id_c_string(dev->id, model_rev, ATA_ID_FW_REV, sizeof(model_rev));
4622 
4623 	while (ad->model_num) {
4624 		if (glob_match(ad->model_num, model_num)) {
4625 			if (ad->model_rev == NULL)
4626 				return ad->horkage;
4627 			if (glob_match(ad->model_rev, model_rev))
4628 				return ad->horkage;
4629 		}
4630 		ad++;
4631 	}
4632 	return 0;
4633 }
4634 
4635 static int ata_dma_blacklisted(const struct ata_device *dev)
4636 {
4637 	/* We don't support polling DMA.
4638 	 * DMA blacklist those ATAPI devices with CDB-intr (and use PIO)
4639 	 * if the LLDD handles only interrupts in the HSM_ST_LAST state.
4640 	 */
4641 	if ((dev->link->ap->flags & ATA_FLAG_PIO_POLLING) &&
4642 	    (dev->flags & ATA_DFLAG_CDB_INTR))
4643 		return 1;
4644 	return (dev->horkage & ATA_HORKAGE_NODMA) ? 1 : 0;
4645 }
4646 
4647 /**
4648  *	ata_is_40wire		-	check drive side detection
4649  *	@dev: device
4650  *
4651  *	Perform drive side detection decoding, allowing for device vendors
4652  *	who can't follow the documentation.
4653  */
4654 
4655 static int ata_is_40wire(struct ata_device *dev)
4656 {
4657 	if (dev->horkage & ATA_HORKAGE_IVB)
4658 		return ata_drive_40wire_relaxed(dev->id);
4659 	return ata_drive_40wire(dev->id);
4660 }
4661 
4662 /**
4663  *	cable_is_40wire		-	40/80/SATA decider
4664  *	@ap: port to consider
4665  *
4666  *	This function encapsulates the policy for speed management
4667  *	in one place. At the moment we don't cache the result but
4668  *	there is a good case for setting ap->cbl to the result when
4669  *	we are called with unknown cables (and figuring out if it
4670  *	impacts hotplug at all).
4671  *
4672  *	Return 1 if the cable appears to be 40 wire.
4673  */
4674 
4675 static int cable_is_40wire(struct ata_port *ap)
4676 {
4677 	struct ata_link *link;
4678 	struct ata_device *dev;
4679 
4680 	/* If the controller thinks we are 40 wire, we are. */
4681 	if (ap->cbl == ATA_CBL_PATA40)
4682 		return 1;
4683 
4684 	/* If the controller thinks we are 80 wire, we are. */
4685 	if (ap->cbl == ATA_CBL_PATA80 || ap->cbl == ATA_CBL_SATA)
4686 		return 0;
4687 
4688 	/* If the system is known to be 40 wire short cable (eg
4689 	 * laptop), then we allow 80 wire modes even if the drive
4690 	 * isn't sure.
4691 	 */
4692 	if (ap->cbl == ATA_CBL_PATA40_SHORT)
4693 		return 0;
4694 
4695 	/* If the controller doesn't know, we scan.
4696 	 *
4697 	 * Note: We look for all 40 wire detects at this point.  Any
4698 	 *       80 wire detect is taken to be 80 wire cable because
4699 	 * - in many setups only the one drive (slave if present) will
4700 	 *   give a valid detect
4701 	 * - if you have a non detect capable drive you don't want it
4702 	 *   to colour the choice
4703 	 */
4704 	ata_for_each_link(link, ap, EDGE) {
4705 		ata_for_each_dev(dev, link, ENABLED) {
4706 			if (!ata_is_40wire(dev))
4707 				return 0;
4708 		}
4709 	}
4710 	return 1;
4711 }
4712 
4713 /**
4714  *	ata_dev_xfermask - Compute supported xfermask of the given device
4715  *	@dev: Device to compute xfermask for
4716  *
4717  *	Compute supported xfermask of @dev and store it in
4718  *	dev->*_mask.  This function is responsible for applying all
4719  *	known limits including host controller limits, device
4720  *	blacklist, etc...
4721  *
4722  *	LOCKING:
4723  *	None.
4724  */
4725 static void ata_dev_xfermask(struct ata_device *dev)
4726 {
4727 	struct ata_link *link = dev->link;
4728 	struct ata_port *ap = link->ap;
4729 	struct ata_host *host = ap->host;
4730 	unsigned long xfer_mask;
4731 
4732 	/* controller modes available */
4733 	xfer_mask = ata_pack_xfermask(ap->pio_mask,
4734 				      ap->mwdma_mask, ap->udma_mask);
4735 
4736 	/* drive modes available */
4737 	xfer_mask &= ata_pack_xfermask(dev->pio_mask,
4738 				       dev->mwdma_mask, dev->udma_mask);
4739 	xfer_mask &= ata_id_xfermask(dev->id);
4740 
4741 	/*
4742 	 *	CFA Advanced TrueIDE timings are not allowed on a shared
4743 	 *	cable
4744 	 */
4745 	if (ata_dev_pair(dev)) {
4746 		/* No PIO5 or PIO6 */
4747 		xfer_mask &= ~(0x03 << (ATA_SHIFT_PIO + 5));
4748 		/* No MWDMA3 or MWDMA 4 */
4749 		xfer_mask &= ~(0x03 << (ATA_SHIFT_MWDMA + 3));
4750 	}
4751 
4752 	if (ata_dma_blacklisted(dev)) {
4753 		xfer_mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA);
4754 		ata_dev_warn(dev,
4755 			     "device is on DMA blacklist, disabling DMA\n");
4756 	}
4757 
4758 	if ((host->flags & ATA_HOST_SIMPLEX) &&
4759 	    host->simplex_claimed && host->simplex_claimed != ap) {
4760 		xfer_mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA);
4761 		ata_dev_warn(dev,
4762 			     "simplex DMA is claimed by other device, disabling DMA\n");
4763 	}
4764 
4765 	if (ap->flags & ATA_FLAG_NO_IORDY)
4766 		xfer_mask &= ata_pio_mask_no_iordy(dev);
4767 
4768 	if (ap->ops->mode_filter)
4769 		xfer_mask = ap->ops->mode_filter(dev, xfer_mask);
4770 
4771 	/* Apply cable rule here.  Don't apply it early because when
4772 	 * we handle hot plug the cable type can itself change.
4773 	 * Check this last so that we know if the transfer rate was
4774 	 * solely limited by the cable.
4775 	 * Unknown or 80 wire cables reported host side are checked
4776 	 * drive side as well. Cases where we know a 40wire cable
4777 	 * is used safely for 80 are not checked here.
4778 	 */
4779 	if (xfer_mask & (0xF8 << ATA_SHIFT_UDMA))
4780 		/* UDMA/44 or higher would be available */
4781 		if (cable_is_40wire(ap)) {
4782 			ata_dev_warn(dev,
4783 				     "limited to UDMA/33 due to 40-wire cable\n");
4784 			xfer_mask &= ~(0xF8 << ATA_SHIFT_UDMA);
4785 		}
4786 
4787 	ata_unpack_xfermask(xfer_mask, &dev->pio_mask,
4788 			    &dev->mwdma_mask, &dev->udma_mask);
4789 }
4790 
4791 /**
4792  *	ata_dev_set_xfermode - Issue SET FEATURES - XFER MODE command
4793  *	@dev: Device to which command will be sent
4794  *
4795  *	Issue SET FEATURES - XFER MODE command to device @dev
4796  *	on port @ap.
4797  *
4798  *	LOCKING:
4799  *	PCI/etc. bus probe sem.
4800  *
4801  *	RETURNS:
4802  *	0 on success, AC_ERR_* mask otherwise.
4803  */
4804 
4805 static unsigned int ata_dev_set_xfermode(struct ata_device *dev)
4806 {
4807 	struct ata_taskfile tf;
4808 	unsigned int err_mask;
4809 
4810 	/* set up set-features taskfile */
4811 	DPRINTK("set features - xfer mode\n");
4812 
4813 	/* Some controllers and ATAPI devices show flaky interrupt
4814 	 * behavior after setting xfer mode.  Use polling instead.
4815 	 */
4816 	ata_tf_init(dev, &tf);
4817 	tf.command = ATA_CMD_SET_FEATURES;
4818 	tf.feature = SETFEATURES_XFER;
4819 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE | ATA_TFLAG_POLLING;
4820 	tf.protocol = ATA_PROT_NODATA;
4821 	/* If we are using IORDY we must send the mode setting command */
4822 	if (ata_pio_need_iordy(dev))
4823 		tf.nsect = dev->xfer_mode;
4824 	/* If the device has IORDY and the controller does not - turn it off */
4825  	else if (ata_id_has_iordy(dev->id))
4826 		tf.nsect = 0x01;
4827 	else /* In the ancient relic department - skip all of this */
4828 		return 0;
4829 
4830 	/* On some disks, this command causes spin-up, so we need longer timeout */
4831 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 15000);
4832 
4833 	DPRINTK("EXIT, err_mask=%x\n", err_mask);
4834 	return err_mask;
4835 }
4836 
4837 /**
4838  *	ata_dev_set_feature - Issue SET FEATURES - SATA FEATURES
4839  *	@dev: Device to which command will be sent
4840  *	@enable: Whether to enable or disable the feature
4841  *	@feature: The sector count represents the feature to set
4842  *
4843  *	Issue SET FEATURES - SATA FEATURES command to device @dev
4844  *	on port @ap with sector count
4845  *
4846  *	LOCKING:
4847  *	PCI/etc. bus probe sem.
4848  *
4849  *	RETURNS:
4850  *	0 on success, AC_ERR_* mask otherwise.
4851  */
4852 unsigned int ata_dev_set_feature(struct ata_device *dev, u8 enable, u8 feature)
4853 {
4854 	struct ata_taskfile tf;
4855 	unsigned int err_mask;
4856 	unsigned long timeout = 0;
4857 
4858 	/* set up set-features taskfile */
4859 	DPRINTK("set features - SATA features\n");
4860 
4861 	ata_tf_init(dev, &tf);
4862 	tf.command = ATA_CMD_SET_FEATURES;
4863 	tf.feature = enable;
4864 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
4865 	tf.protocol = ATA_PROT_NODATA;
4866 	tf.nsect = feature;
4867 
4868 	if (enable == SETFEATURES_SPINUP)
4869 		timeout = ata_probe_timeout ?
4870 			  ata_probe_timeout * 1000 : SETFEATURES_SPINUP_TIMEOUT;
4871 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, timeout);
4872 
4873 	DPRINTK("EXIT, err_mask=%x\n", err_mask);
4874 	return err_mask;
4875 }
4876 EXPORT_SYMBOL_GPL(ata_dev_set_feature);
4877 
4878 /**
4879  *	ata_dev_init_params - Issue INIT DEV PARAMS command
4880  *	@dev: Device to which command will be sent
4881  *	@heads: Number of heads (taskfile parameter)
4882  *	@sectors: Number of sectors (taskfile parameter)
4883  *
4884  *	LOCKING:
4885  *	Kernel thread context (may sleep)
4886  *
4887  *	RETURNS:
4888  *	0 on success, AC_ERR_* mask otherwise.
4889  */
4890 static unsigned int ata_dev_init_params(struct ata_device *dev,
4891 					u16 heads, u16 sectors)
4892 {
4893 	struct ata_taskfile tf;
4894 	unsigned int err_mask;
4895 
4896 	/* Number of sectors per track 1-255. Number of heads 1-16 */
4897 	if (sectors < 1 || sectors > 255 || heads < 1 || heads > 16)
4898 		return AC_ERR_INVALID;
4899 
4900 	/* set up init dev params taskfile */
4901 	DPRINTK("init dev params \n");
4902 
4903 	ata_tf_init(dev, &tf);
4904 	tf.command = ATA_CMD_INIT_DEV_PARAMS;
4905 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
4906 	tf.protocol = ATA_PROT_NODATA;
4907 	tf.nsect = sectors;
4908 	tf.device |= (heads - 1) & 0x0f; /* max head = num. of heads - 1 */
4909 
4910 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
4911 	/* A clean abort indicates an original or just out of spec drive
4912 	   and we should continue as we issue the setup based on the
4913 	   drive reported working geometry */
4914 	if (err_mask == AC_ERR_DEV && (tf.feature & ATA_ABORTED))
4915 		err_mask = 0;
4916 
4917 	DPRINTK("EXIT, err_mask=%x\n", err_mask);
4918 	return err_mask;
4919 }
4920 
4921 /**
4922  *	atapi_check_dma - Check whether ATAPI DMA can be supported
4923  *	@qc: Metadata associated with taskfile to check
4924  *
4925  *	Allow low-level driver to filter ATA PACKET commands, returning
4926  *	a status indicating whether or not it is OK to use DMA for the
4927  *	supplied PACKET command.
4928  *
4929  *	LOCKING:
4930  *	spin_lock_irqsave(host lock)
4931  *
4932  *	RETURNS: 0 when ATAPI DMA can be used
4933  *               nonzero otherwise
4934  */
4935 int atapi_check_dma(struct ata_queued_cmd *qc)
4936 {
4937 	struct ata_port *ap = qc->ap;
4938 
4939 	/* Don't allow DMA if it isn't multiple of 16 bytes.  Quite a
4940 	 * few ATAPI devices choke on such DMA requests.
4941 	 */
4942 	if (!(qc->dev->horkage & ATA_HORKAGE_ATAPI_MOD16_DMA) &&
4943 	    unlikely(qc->nbytes & 15))
4944 		return 1;
4945 
4946 	if (ap->ops->check_atapi_dma)
4947 		return ap->ops->check_atapi_dma(qc);
4948 
4949 	return 0;
4950 }
4951 
4952 /**
4953  *	ata_std_qc_defer - Check whether a qc needs to be deferred
4954  *	@qc: ATA command in question
4955  *
4956  *	Non-NCQ commands cannot run with any other command, NCQ or
4957  *	not.  As upper layer only knows the queue depth, we are
4958  *	responsible for maintaining exclusion.  This function checks
4959  *	whether a new command @qc can be issued.
4960  *
4961  *	LOCKING:
4962  *	spin_lock_irqsave(host lock)
4963  *
4964  *	RETURNS:
4965  *	ATA_DEFER_* if deferring is needed, 0 otherwise.
4966  */
4967 int ata_std_qc_defer(struct ata_queued_cmd *qc)
4968 {
4969 	struct ata_link *link = qc->dev->link;
4970 
4971 	if (ata_is_ncq(qc->tf.protocol)) {
4972 		if (!ata_tag_valid(link->active_tag))
4973 			return 0;
4974 	} else {
4975 		if (!ata_tag_valid(link->active_tag) && !link->sactive)
4976 			return 0;
4977 	}
4978 
4979 	return ATA_DEFER_LINK;
4980 }
4981 
4982 void ata_noop_qc_prep(struct ata_queued_cmd *qc) { }
4983 
4984 /**
4985  *	ata_sg_init - Associate command with scatter-gather table.
4986  *	@qc: Command to be associated
4987  *	@sg: Scatter-gather table.
4988  *	@n_elem: Number of elements in s/g table.
4989  *
4990  *	Initialize the data-related elements of queued_cmd @qc
4991  *	to point to a scatter-gather table @sg, containing @n_elem
4992  *	elements.
4993  *
4994  *	LOCKING:
4995  *	spin_lock_irqsave(host lock)
4996  */
4997 void ata_sg_init(struct ata_queued_cmd *qc, struct scatterlist *sg,
4998 		 unsigned int n_elem)
4999 {
5000 	qc->sg = sg;
5001 	qc->n_elem = n_elem;
5002 	qc->cursg = qc->sg;
5003 }
5004 
5005 #ifdef CONFIG_HAS_DMA
5006 
5007 /**
5008  *	ata_sg_clean - Unmap DMA memory associated with command
5009  *	@qc: Command containing DMA memory to be released
5010  *
5011  *	Unmap all mapped DMA memory associated with this command.
5012  *
5013  *	LOCKING:
5014  *	spin_lock_irqsave(host lock)
5015  */
5016 static void ata_sg_clean(struct ata_queued_cmd *qc)
5017 {
5018 	struct ata_port *ap = qc->ap;
5019 	struct scatterlist *sg = qc->sg;
5020 	int dir = qc->dma_dir;
5021 
5022 	WARN_ON_ONCE(sg == NULL);
5023 
5024 	VPRINTK("unmapping %u sg elements\n", qc->n_elem);
5025 
5026 	if (qc->n_elem)
5027 		dma_unmap_sg(ap->dev, sg, qc->orig_n_elem, dir);
5028 
5029 	qc->flags &= ~ATA_QCFLAG_DMAMAP;
5030 	qc->sg = NULL;
5031 }
5032 
5033 /**
5034  *	ata_sg_setup - DMA-map the scatter-gather table associated with a command.
5035  *	@qc: Command with scatter-gather table to be mapped.
5036  *
5037  *	DMA-map the scatter-gather table associated with queued_cmd @qc.
5038  *
5039  *	LOCKING:
5040  *	spin_lock_irqsave(host lock)
5041  *
5042  *	RETURNS:
5043  *	Zero on success, negative on error.
5044  *
5045  */
5046 static int ata_sg_setup(struct ata_queued_cmd *qc)
5047 {
5048 	struct ata_port *ap = qc->ap;
5049 	unsigned int n_elem;
5050 
5051 	VPRINTK("ENTER, ata%u\n", ap->print_id);
5052 
5053 	n_elem = dma_map_sg(ap->dev, qc->sg, qc->n_elem, qc->dma_dir);
5054 	if (n_elem < 1)
5055 		return -1;
5056 
5057 	VPRINTK("%d sg elements mapped\n", n_elem);
5058 	qc->orig_n_elem = qc->n_elem;
5059 	qc->n_elem = n_elem;
5060 	qc->flags |= ATA_QCFLAG_DMAMAP;
5061 
5062 	return 0;
5063 }
5064 
5065 #else /* !CONFIG_HAS_DMA */
5066 
5067 static inline void ata_sg_clean(struct ata_queued_cmd *qc) {}
5068 static inline int ata_sg_setup(struct ata_queued_cmd *qc) { return -1; }
5069 
5070 #endif /* !CONFIG_HAS_DMA */
5071 
5072 /**
5073  *	swap_buf_le16 - swap halves of 16-bit words in place
5074  *	@buf:  Buffer to swap
5075  *	@buf_words:  Number of 16-bit words in buffer.
5076  *
5077  *	Swap halves of 16-bit words if needed to convert from
5078  *	little-endian byte order to native cpu byte order, or
5079  *	vice-versa.
5080  *
5081  *	LOCKING:
5082  *	Inherited from caller.
5083  */
5084 void swap_buf_le16(u16 *buf, unsigned int buf_words)
5085 {
5086 #ifdef __BIG_ENDIAN
5087 	unsigned int i;
5088 
5089 	for (i = 0; i < buf_words; i++)
5090 		buf[i] = le16_to_cpu(buf[i]);
5091 #endif /* __BIG_ENDIAN */
5092 }
5093 
5094 /**
5095  *	ata_qc_new_init - Request an available ATA command, and initialize it
5096  *	@dev: Device from whom we request an available command structure
5097  *	@tag: tag
5098  *
5099  *	LOCKING:
5100  *	None.
5101  */
5102 
5103 struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev, int tag)
5104 {
5105 	struct ata_port *ap = dev->link->ap;
5106 	struct ata_queued_cmd *qc;
5107 
5108 	/* no command while frozen */
5109 	if (unlikely(ap->pflags & ATA_PFLAG_FROZEN))
5110 		return NULL;
5111 
5112 	/* libsas case */
5113 	if (ap->flags & ATA_FLAG_SAS_HOST) {
5114 		tag = ata_sas_allocate_tag(ap);
5115 		if (tag < 0)
5116 			return NULL;
5117 	}
5118 
5119 	qc = __ata_qc_from_tag(ap, tag);
5120 	qc->tag = qc->hw_tag = tag;
5121 	qc->scsicmd = NULL;
5122 	qc->ap = ap;
5123 	qc->dev = dev;
5124 
5125 	ata_qc_reinit(qc);
5126 
5127 	return qc;
5128 }
5129 
5130 /**
5131  *	ata_qc_free - free unused ata_queued_cmd
5132  *	@qc: Command to complete
5133  *
5134  *	Designed to free unused ata_queued_cmd object
5135  *	in case something prevents using it.
5136  *
5137  *	LOCKING:
5138  *	spin_lock_irqsave(host lock)
5139  */
5140 void ata_qc_free(struct ata_queued_cmd *qc)
5141 {
5142 	struct ata_port *ap;
5143 	unsigned int tag;
5144 
5145 	WARN_ON_ONCE(qc == NULL); /* ata_qc_from_tag _might_ return NULL */
5146 	ap = qc->ap;
5147 
5148 	qc->flags = 0;
5149 	tag = qc->tag;
5150 	if (ata_tag_valid(tag)) {
5151 		qc->tag = ATA_TAG_POISON;
5152 		if (ap->flags & ATA_FLAG_SAS_HOST)
5153 			ata_sas_free_tag(tag, ap);
5154 	}
5155 }
5156 
5157 void __ata_qc_complete(struct ata_queued_cmd *qc)
5158 {
5159 	struct ata_port *ap;
5160 	struct ata_link *link;
5161 
5162 	WARN_ON_ONCE(qc == NULL); /* ata_qc_from_tag _might_ return NULL */
5163 	WARN_ON_ONCE(!(qc->flags & ATA_QCFLAG_ACTIVE));
5164 	ap = qc->ap;
5165 	link = qc->dev->link;
5166 
5167 	if (likely(qc->flags & ATA_QCFLAG_DMAMAP))
5168 		ata_sg_clean(qc);
5169 
5170 	/* command should be marked inactive atomically with qc completion */
5171 	if (ata_is_ncq(qc->tf.protocol)) {
5172 		link->sactive &= ~(1 << qc->hw_tag);
5173 		if (!link->sactive)
5174 			ap->nr_active_links--;
5175 	} else {
5176 		link->active_tag = ATA_TAG_POISON;
5177 		ap->nr_active_links--;
5178 	}
5179 
5180 	/* clear exclusive status */
5181 	if (unlikely(qc->flags & ATA_QCFLAG_CLEAR_EXCL &&
5182 		     ap->excl_link == link))
5183 		ap->excl_link = NULL;
5184 
5185 	/* atapi: mark qc as inactive to prevent the interrupt handler
5186 	 * from completing the command twice later, before the error handler
5187 	 * is called. (when rc != 0 and atapi request sense is needed)
5188 	 */
5189 	qc->flags &= ~ATA_QCFLAG_ACTIVE;
5190 	ap->qc_active &= ~(1ULL << qc->tag);
5191 
5192 	/* call completion callback */
5193 	qc->complete_fn(qc);
5194 }
5195 
5196 static void fill_result_tf(struct ata_queued_cmd *qc)
5197 {
5198 	struct ata_port *ap = qc->ap;
5199 
5200 	qc->result_tf.flags = qc->tf.flags;
5201 	ap->ops->qc_fill_rtf(qc);
5202 }
5203 
5204 static void ata_verify_xfer(struct ata_queued_cmd *qc)
5205 {
5206 	struct ata_device *dev = qc->dev;
5207 
5208 	if (!ata_is_data(qc->tf.protocol))
5209 		return;
5210 
5211 	if ((dev->mwdma_mask || dev->udma_mask) && ata_is_pio(qc->tf.protocol))
5212 		return;
5213 
5214 	dev->flags &= ~ATA_DFLAG_DUBIOUS_XFER;
5215 }
5216 
5217 /**
5218  *	ata_qc_complete - Complete an active ATA command
5219  *	@qc: Command to complete
5220  *
5221  *	Indicate to the mid and upper layers that an ATA command has
5222  *	completed, with either an ok or not-ok status.
5223  *
5224  *	Refrain from calling this function multiple times when
5225  *	successfully completing multiple NCQ commands.
5226  *	ata_qc_complete_multiple() should be used instead, which will
5227  *	properly update IRQ expect state.
5228  *
5229  *	LOCKING:
5230  *	spin_lock_irqsave(host lock)
5231  */
5232 void ata_qc_complete(struct ata_queued_cmd *qc)
5233 {
5234 	struct ata_port *ap = qc->ap;
5235 
5236 	/* Trigger the LED (if available) */
5237 	ledtrig_disk_activity(!!(qc->tf.flags & ATA_TFLAG_WRITE));
5238 
5239 	/* XXX: New EH and old EH use different mechanisms to
5240 	 * synchronize EH with regular execution path.
5241 	 *
5242 	 * In new EH, a failed qc is marked with ATA_QCFLAG_FAILED.
5243 	 * Normal execution path is responsible for not accessing a
5244 	 * failed qc.  libata core enforces the rule by returning NULL
5245 	 * from ata_qc_from_tag() for failed qcs.
5246 	 *
5247 	 * Old EH depends on ata_qc_complete() nullifying completion
5248 	 * requests if ATA_QCFLAG_EH_SCHEDULED is set.  Old EH does
5249 	 * not synchronize with interrupt handler.  Only PIO task is
5250 	 * taken care of.
5251 	 */
5252 	if (ap->ops->error_handler) {
5253 		struct ata_device *dev = qc->dev;
5254 		struct ata_eh_info *ehi = &dev->link->eh_info;
5255 
5256 		if (unlikely(qc->err_mask))
5257 			qc->flags |= ATA_QCFLAG_FAILED;
5258 
5259 		/*
5260 		 * Finish internal commands without any further processing
5261 		 * and always with the result TF filled.
5262 		 */
5263 		if (unlikely(ata_tag_internal(qc->tag))) {
5264 			fill_result_tf(qc);
5265 			trace_ata_qc_complete_internal(qc);
5266 			__ata_qc_complete(qc);
5267 			return;
5268 		}
5269 
5270 		/*
5271 		 * Non-internal qc has failed.  Fill the result TF and
5272 		 * summon EH.
5273 		 */
5274 		if (unlikely(qc->flags & ATA_QCFLAG_FAILED)) {
5275 			fill_result_tf(qc);
5276 			trace_ata_qc_complete_failed(qc);
5277 			ata_qc_schedule_eh(qc);
5278 			return;
5279 		}
5280 
5281 		WARN_ON_ONCE(ap->pflags & ATA_PFLAG_FROZEN);
5282 
5283 		/* read result TF if requested */
5284 		if (qc->flags & ATA_QCFLAG_RESULT_TF)
5285 			fill_result_tf(qc);
5286 
5287 		trace_ata_qc_complete_done(qc);
5288 		/* Some commands need post-processing after successful
5289 		 * completion.
5290 		 */
5291 		switch (qc->tf.command) {
5292 		case ATA_CMD_SET_FEATURES:
5293 			if (qc->tf.feature != SETFEATURES_WC_ON &&
5294 			    qc->tf.feature != SETFEATURES_WC_OFF &&
5295 			    qc->tf.feature != SETFEATURES_RA_ON &&
5296 			    qc->tf.feature != SETFEATURES_RA_OFF)
5297 				break;
5298 			/* fall through */
5299 		case ATA_CMD_INIT_DEV_PARAMS: /* CHS translation changed */
5300 		case ATA_CMD_SET_MULTI: /* multi_count changed */
5301 			/* revalidate device */
5302 			ehi->dev_action[dev->devno] |= ATA_EH_REVALIDATE;
5303 			ata_port_schedule_eh(ap);
5304 			break;
5305 
5306 		case ATA_CMD_SLEEP:
5307 			dev->flags |= ATA_DFLAG_SLEEPING;
5308 			break;
5309 		}
5310 
5311 		if (unlikely(dev->flags & ATA_DFLAG_DUBIOUS_XFER))
5312 			ata_verify_xfer(qc);
5313 
5314 		__ata_qc_complete(qc);
5315 	} else {
5316 		if (qc->flags & ATA_QCFLAG_EH_SCHEDULED)
5317 			return;
5318 
5319 		/* read result TF if failed or requested */
5320 		if (qc->err_mask || qc->flags & ATA_QCFLAG_RESULT_TF)
5321 			fill_result_tf(qc);
5322 
5323 		__ata_qc_complete(qc);
5324 	}
5325 }
5326 
5327 /**
5328  *	ata_qc_complete_multiple - Complete multiple qcs successfully
5329  *	@ap: port in question
5330  *	@qc_active: new qc_active mask
5331  *
5332  *	Complete in-flight commands.  This functions is meant to be
5333  *	called from low-level driver's interrupt routine to complete
5334  *	requests normally.  ap->qc_active and @qc_active is compared
5335  *	and commands are completed accordingly.
5336  *
5337  *	Always use this function when completing multiple NCQ commands
5338  *	from IRQ handlers instead of calling ata_qc_complete()
5339  *	multiple times to keep IRQ expect status properly in sync.
5340  *
5341  *	LOCKING:
5342  *	spin_lock_irqsave(host lock)
5343  *
5344  *	RETURNS:
5345  *	Number of completed commands on success, -errno otherwise.
5346  */
5347 int ata_qc_complete_multiple(struct ata_port *ap, u64 qc_active)
5348 {
5349 	u64 done_mask, ap_qc_active = ap->qc_active;
5350 	int nr_done = 0;
5351 
5352 	/*
5353 	 * If the internal tag is set on ap->qc_active, then we care about
5354 	 * bit0 on the passed in qc_active mask. Move that bit up to match
5355 	 * the internal tag.
5356 	 */
5357 	if (ap_qc_active & (1ULL << ATA_TAG_INTERNAL)) {
5358 		qc_active |= (qc_active & 0x01) << ATA_TAG_INTERNAL;
5359 		qc_active ^= qc_active & 0x01;
5360 	}
5361 
5362 	done_mask = ap_qc_active ^ qc_active;
5363 
5364 	if (unlikely(done_mask & qc_active)) {
5365 		ata_port_err(ap, "illegal qc_active transition (%08llx->%08llx)\n",
5366 			     ap->qc_active, qc_active);
5367 		return -EINVAL;
5368 	}
5369 
5370 	while (done_mask) {
5371 		struct ata_queued_cmd *qc;
5372 		unsigned int tag = __ffs64(done_mask);
5373 
5374 		qc = ata_qc_from_tag(ap, tag);
5375 		if (qc) {
5376 			ata_qc_complete(qc);
5377 			nr_done++;
5378 		}
5379 		done_mask &= ~(1ULL << tag);
5380 	}
5381 
5382 	return nr_done;
5383 }
5384 
5385 /**
5386  *	ata_qc_issue - issue taskfile to device
5387  *	@qc: command to issue to device
5388  *
5389  *	Prepare an ATA command to submission to device.
5390  *	This includes mapping the data into a DMA-able
5391  *	area, filling in the S/G table, and finally
5392  *	writing the taskfile to hardware, starting the command.
5393  *
5394  *	LOCKING:
5395  *	spin_lock_irqsave(host lock)
5396  */
5397 void ata_qc_issue(struct ata_queued_cmd *qc)
5398 {
5399 	struct ata_port *ap = qc->ap;
5400 	struct ata_link *link = qc->dev->link;
5401 	u8 prot = qc->tf.protocol;
5402 
5403 	/* Make sure only one non-NCQ command is outstanding.  The
5404 	 * check is skipped for old EH because it reuses active qc to
5405 	 * request ATAPI sense.
5406 	 */
5407 	WARN_ON_ONCE(ap->ops->error_handler && ata_tag_valid(link->active_tag));
5408 
5409 	if (ata_is_ncq(prot)) {
5410 		WARN_ON_ONCE(link->sactive & (1 << qc->hw_tag));
5411 
5412 		if (!link->sactive)
5413 			ap->nr_active_links++;
5414 		link->sactive |= 1 << qc->hw_tag;
5415 	} else {
5416 		WARN_ON_ONCE(link->sactive);
5417 
5418 		ap->nr_active_links++;
5419 		link->active_tag = qc->tag;
5420 	}
5421 
5422 	qc->flags |= ATA_QCFLAG_ACTIVE;
5423 	ap->qc_active |= 1ULL << qc->tag;
5424 
5425 	/*
5426 	 * We guarantee to LLDs that they will have at least one
5427 	 * non-zero sg if the command is a data command.
5428 	 */
5429 	if (ata_is_data(prot) && (!qc->sg || !qc->n_elem || !qc->nbytes))
5430 		goto sys_err;
5431 
5432 	if (ata_is_dma(prot) || (ata_is_pio(prot) &&
5433 				 (ap->flags & ATA_FLAG_PIO_DMA)))
5434 		if (ata_sg_setup(qc))
5435 			goto sys_err;
5436 
5437 	/* if device is sleeping, schedule reset and abort the link */
5438 	if (unlikely(qc->dev->flags & ATA_DFLAG_SLEEPING)) {
5439 		link->eh_info.action |= ATA_EH_RESET;
5440 		ata_ehi_push_desc(&link->eh_info, "waking up from sleep");
5441 		ata_link_abort(link);
5442 		return;
5443 	}
5444 
5445 	ap->ops->qc_prep(qc);
5446 	trace_ata_qc_issue(qc);
5447 	qc->err_mask |= ap->ops->qc_issue(qc);
5448 	if (unlikely(qc->err_mask))
5449 		goto err;
5450 	return;
5451 
5452 sys_err:
5453 	qc->err_mask |= AC_ERR_SYSTEM;
5454 err:
5455 	ata_qc_complete(qc);
5456 }
5457 
5458 /**
5459  *	sata_scr_valid - test whether SCRs are accessible
5460  *	@link: ATA link to test SCR accessibility for
5461  *
5462  *	Test whether SCRs are accessible for @link.
5463  *
5464  *	LOCKING:
5465  *	None.
5466  *
5467  *	RETURNS:
5468  *	1 if SCRs are accessible, 0 otherwise.
5469  */
5470 int sata_scr_valid(struct ata_link *link)
5471 {
5472 	struct ata_port *ap = link->ap;
5473 
5474 	return (ap->flags & ATA_FLAG_SATA) && ap->ops->scr_read;
5475 }
5476 
5477 /**
5478  *	sata_scr_read - read SCR register of the specified port
5479  *	@link: ATA link to read SCR for
5480  *	@reg: SCR to read
5481  *	@val: Place to store read value
5482  *
5483  *	Read SCR register @reg of @link into *@val.  This function is
5484  *	guaranteed to succeed if @link is ap->link, the cable type of
5485  *	the port is SATA and the port implements ->scr_read.
5486  *
5487  *	LOCKING:
5488  *	None if @link is ap->link.  Kernel thread context otherwise.
5489  *
5490  *	RETURNS:
5491  *	0 on success, negative errno on failure.
5492  */
5493 int sata_scr_read(struct ata_link *link, int reg, u32 *val)
5494 {
5495 	if (ata_is_host_link(link)) {
5496 		if (sata_scr_valid(link))
5497 			return link->ap->ops->scr_read(link, reg, val);
5498 		return -EOPNOTSUPP;
5499 	}
5500 
5501 	return sata_pmp_scr_read(link, reg, val);
5502 }
5503 
5504 /**
5505  *	sata_scr_write - write SCR register of the specified port
5506  *	@link: ATA link to write SCR for
5507  *	@reg: SCR to write
5508  *	@val: value to write
5509  *
5510  *	Write @val to SCR register @reg of @link.  This function is
5511  *	guaranteed to succeed if @link is ap->link, the cable type of
5512  *	the port is SATA and the port implements ->scr_read.
5513  *
5514  *	LOCKING:
5515  *	None if @link is ap->link.  Kernel thread context otherwise.
5516  *
5517  *	RETURNS:
5518  *	0 on success, negative errno on failure.
5519  */
5520 int sata_scr_write(struct ata_link *link, int reg, u32 val)
5521 {
5522 	if (ata_is_host_link(link)) {
5523 		if (sata_scr_valid(link))
5524 			return link->ap->ops->scr_write(link, reg, val);
5525 		return -EOPNOTSUPP;
5526 	}
5527 
5528 	return sata_pmp_scr_write(link, reg, val);
5529 }
5530 
5531 /**
5532  *	sata_scr_write_flush - write SCR register of the specified port and flush
5533  *	@link: ATA link to write SCR for
5534  *	@reg: SCR to write
5535  *	@val: value to write
5536  *
5537  *	This function is identical to sata_scr_write() except that this
5538  *	function performs flush after writing to the register.
5539  *
5540  *	LOCKING:
5541  *	None if @link is ap->link.  Kernel thread context otherwise.
5542  *
5543  *	RETURNS:
5544  *	0 on success, negative errno on failure.
5545  */
5546 int sata_scr_write_flush(struct ata_link *link, int reg, u32 val)
5547 {
5548 	if (ata_is_host_link(link)) {
5549 		int rc;
5550 
5551 		if (sata_scr_valid(link)) {
5552 			rc = link->ap->ops->scr_write(link, reg, val);
5553 			if (rc == 0)
5554 				rc = link->ap->ops->scr_read(link, reg, &val);
5555 			return rc;
5556 		}
5557 		return -EOPNOTSUPP;
5558 	}
5559 
5560 	return sata_pmp_scr_write(link, reg, val);
5561 }
5562 
5563 /**
5564  *	ata_phys_link_online - test whether the given link is online
5565  *	@link: ATA link to test
5566  *
5567  *	Test whether @link is online.  Note that this function returns
5568  *	0 if online status of @link cannot be obtained, so
5569  *	ata_link_online(link) != !ata_link_offline(link).
5570  *
5571  *	LOCKING:
5572  *	None.
5573  *
5574  *	RETURNS:
5575  *	True if the port online status is available and online.
5576  */
5577 bool ata_phys_link_online(struct ata_link *link)
5578 {
5579 	u32 sstatus;
5580 
5581 	if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0 &&
5582 	    ata_sstatus_online(sstatus))
5583 		return true;
5584 	return false;
5585 }
5586 
5587 /**
5588  *	ata_phys_link_offline - test whether the given link is offline
5589  *	@link: ATA link to test
5590  *
5591  *	Test whether @link is offline.  Note that this function
5592  *	returns 0 if offline status of @link cannot be obtained, so
5593  *	ata_link_online(link) != !ata_link_offline(link).
5594  *
5595  *	LOCKING:
5596  *	None.
5597  *
5598  *	RETURNS:
5599  *	True if the port offline status is available and offline.
5600  */
5601 bool ata_phys_link_offline(struct ata_link *link)
5602 {
5603 	u32 sstatus;
5604 
5605 	if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0 &&
5606 	    !ata_sstatus_online(sstatus))
5607 		return true;
5608 	return false;
5609 }
5610 
5611 /**
5612  *	ata_link_online - test whether the given link is online
5613  *	@link: ATA link to test
5614  *
5615  *	Test whether @link is online.  This is identical to
5616  *	ata_phys_link_online() when there's no slave link.  When
5617  *	there's a slave link, this function should only be called on
5618  *	the master link and will return true if any of M/S links is
5619  *	online.
5620  *
5621  *	LOCKING:
5622  *	None.
5623  *
5624  *	RETURNS:
5625  *	True if the port online status is available and online.
5626  */
5627 bool ata_link_online(struct ata_link *link)
5628 {
5629 	struct ata_link *slave = link->ap->slave_link;
5630 
5631 	WARN_ON(link == slave);	/* shouldn't be called on slave link */
5632 
5633 	return ata_phys_link_online(link) ||
5634 		(slave && ata_phys_link_online(slave));
5635 }
5636 
5637 /**
5638  *	ata_link_offline - test whether the given link is offline
5639  *	@link: ATA link to test
5640  *
5641  *	Test whether @link is offline.  This is identical to
5642  *	ata_phys_link_offline() when there's no slave link.  When
5643  *	there's a slave link, this function should only be called on
5644  *	the master link and will return true if both M/S links are
5645  *	offline.
5646  *
5647  *	LOCKING:
5648  *	None.
5649  *
5650  *	RETURNS:
5651  *	True if the port offline status is available and offline.
5652  */
5653 bool ata_link_offline(struct ata_link *link)
5654 {
5655 	struct ata_link *slave = link->ap->slave_link;
5656 
5657 	WARN_ON(link == slave);	/* shouldn't be called on slave link */
5658 
5659 	return ata_phys_link_offline(link) &&
5660 		(!slave || ata_phys_link_offline(slave));
5661 }
5662 
5663 #ifdef CONFIG_PM
5664 static void ata_port_request_pm(struct ata_port *ap, pm_message_t mesg,
5665 				unsigned int action, unsigned int ehi_flags,
5666 				bool async)
5667 {
5668 	struct ata_link *link;
5669 	unsigned long flags;
5670 
5671 	/* Previous resume operation might still be in
5672 	 * progress.  Wait for PM_PENDING to clear.
5673 	 */
5674 	if (ap->pflags & ATA_PFLAG_PM_PENDING) {
5675 		ata_port_wait_eh(ap);
5676 		WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
5677 	}
5678 
5679 	/* request PM ops to EH */
5680 	spin_lock_irqsave(ap->lock, flags);
5681 
5682 	ap->pm_mesg = mesg;
5683 	ap->pflags |= ATA_PFLAG_PM_PENDING;
5684 	ata_for_each_link(link, ap, HOST_FIRST) {
5685 		link->eh_info.action |= action;
5686 		link->eh_info.flags |= ehi_flags;
5687 	}
5688 
5689 	ata_port_schedule_eh(ap);
5690 
5691 	spin_unlock_irqrestore(ap->lock, flags);
5692 
5693 	if (!async) {
5694 		ata_port_wait_eh(ap);
5695 		WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
5696 	}
5697 }
5698 
5699 /*
5700  * On some hardware, device fails to respond after spun down for suspend.  As
5701  * the device won't be used before being resumed, we don't need to touch the
5702  * device.  Ask EH to skip the usual stuff and proceed directly to suspend.
5703  *
5704  * http://thread.gmane.org/gmane.linux.ide/46764
5705  */
5706 static const unsigned int ata_port_suspend_ehi = ATA_EHI_QUIET
5707 						 | ATA_EHI_NO_AUTOPSY
5708 						 | ATA_EHI_NO_RECOVERY;
5709 
5710 static void ata_port_suspend(struct ata_port *ap, pm_message_t mesg)
5711 {
5712 	ata_port_request_pm(ap, mesg, 0, ata_port_suspend_ehi, false);
5713 }
5714 
5715 static void ata_port_suspend_async(struct ata_port *ap, pm_message_t mesg)
5716 {
5717 	ata_port_request_pm(ap, mesg, 0, ata_port_suspend_ehi, true);
5718 }
5719 
5720 static int ata_port_pm_suspend(struct device *dev)
5721 {
5722 	struct ata_port *ap = to_ata_port(dev);
5723 
5724 	if (pm_runtime_suspended(dev))
5725 		return 0;
5726 
5727 	ata_port_suspend(ap, PMSG_SUSPEND);
5728 	return 0;
5729 }
5730 
5731 static int ata_port_pm_freeze(struct device *dev)
5732 {
5733 	struct ata_port *ap = to_ata_port(dev);
5734 
5735 	if (pm_runtime_suspended(dev))
5736 		return 0;
5737 
5738 	ata_port_suspend(ap, PMSG_FREEZE);
5739 	return 0;
5740 }
5741 
5742 static int ata_port_pm_poweroff(struct device *dev)
5743 {
5744 	ata_port_suspend(to_ata_port(dev), PMSG_HIBERNATE);
5745 	return 0;
5746 }
5747 
5748 static const unsigned int ata_port_resume_ehi = ATA_EHI_NO_AUTOPSY
5749 						| ATA_EHI_QUIET;
5750 
5751 static void ata_port_resume(struct ata_port *ap, pm_message_t mesg)
5752 {
5753 	ata_port_request_pm(ap, mesg, ATA_EH_RESET, ata_port_resume_ehi, false);
5754 }
5755 
5756 static void ata_port_resume_async(struct ata_port *ap, pm_message_t mesg)
5757 {
5758 	ata_port_request_pm(ap, mesg, ATA_EH_RESET, ata_port_resume_ehi, true);
5759 }
5760 
5761 static int ata_port_pm_resume(struct device *dev)
5762 {
5763 	ata_port_resume_async(to_ata_port(dev), PMSG_RESUME);
5764 	pm_runtime_disable(dev);
5765 	pm_runtime_set_active(dev);
5766 	pm_runtime_enable(dev);
5767 	return 0;
5768 }
5769 
5770 /*
5771  * For ODDs, the upper layer will poll for media change every few seconds,
5772  * which will make it enter and leave suspend state every few seconds. And
5773  * as each suspend will cause a hard/soft reset, the gain of runtime suspend
5774  * is very little and the ODD may malfunction after constantly being reset.
5775  * So the idle callback here will not proceed to suspend if a non-ZPODD capable
5776  * ODD is attached to the port.
5777  */
5778 static int ata_port_runtime_idle(struct device *dev)
5779 {
5780 	struct ata_port *ap = to_ata_port(dev);
5781 	struct ata_link *link;
5782 	struct ata_device *adev;
5783 
5784 	ata_for_each_link(link, ap, HOST_FIRST) {
5785 		ata_for_each_dev(adev, link, ENABLED)
5786 			if (adev->class == ATA_DEV_ATAPI &&
5787 			    !zpodd_dev_enabled(adev))
5788 				return -EBUSY;
5789 	}
5790 
5791 	return 0;
5792 }
5793 
5794 static int ata_port_runtime_suspend(struct device *dev)
5795 {
5796 	ata_port_suspend(to_ata_port(dev), PMSG_AUTO_SUSPEND);
5797 	return 0;
5798 }
5799 
5800 static int ata_port_runtime_resume(struct device *dev)
5801 {
5802 	ata_port_resume(to_ata_port(dev), PMSG_AUTO_RESUME);
5803 	return 0;
5804 }
5805 
5806 static const struct dev_pm_ops ata_port_pm_ops = {
5807 	.suspend = ata_port_pm_suspend,
5808 	.resume = ata_port_pm_resume,
5809 	.freeze = ata_port_pm_freeze,
5810 	.thaw = ata_port_pm_resume,
5811 	.poweroff = ata_port_pm_poweroff,
5812 	.restore = ata_port_pm_resume,
5813 
5814 	.runtime_suspend = ata_port_runtime_suspend,
5815 	.runtime_resume = ata_port_runtime_resume,
5816 	.runtime_idle = ata_port_runtime_idle,
5817 };
5818 
5819 /* sas ports don't participate in pm runtime management of ata_ports,
5820  * and need to resume ata devices at the domain level, not the per-port
5821  * level. sas suspend/resume is async to allow parallel port recovery
5822  * since sas has multiple ata_port instances per Scsi_Host.
5823  */
5824 void ata_sas_port_suspend(struct ata_port *ap)
5825 {
5826 	ata_port_suspend_async(ap, PMSG_SUSPEND);
5827 }
5828 EXPORT_SYMBOL_GPL(ata_sas_port_suspend);
5829 
5830 void ata_sas_port_resume(struct ata_port *ap)
5831 {
5832 	ata_port_resume_async(ap, PMSG_RESUME);
5833 }
5834 EXPORT_SYMBOL_GPL(ata_sas_port_resume);
5835 
5836 /**
5837  *	ata_host_suspend - suspend host
5838  *	@host: host to suspend
5839  *	@mesg: PM message
5840  *
5841  *	Suspend @host.  Actual operation is performed by port suspend.
5842  */
5843 int ata_host_suspend(struct ata_host *host, pm_message_t mesg)
5844 {
5845 	host->dev->power.power_state = mesg;
5846 	return 0;
5847 }
5848 
5849 /**
5850  *	ata_host_resume - resume host
5851  *	@host: host to resume
5852  *
5853  *	Resume @host.  Actual operation is performed by port resume.
5854  */
5855 void ata_host_resume(struct ata_host *host)
5856 {
5857 	host->dev->power.power_state = PMSG_ON;
5858 }
5859 #endif
5860 
5861 const struct device_type ata_port_type = {
5862 	.name = "ata_port",
5863 #ifdef CONFIG_PM
5864 	.pm = &ata_port_pm_ops,
5865 #endif
5866 };
5867 
5868 /**
5869  *	ata_dev_init - Initialize an ata_device structure
5870  *	@dev: Device structure to initialize
5871  *
5872  *	Initialize @dev in preparation for probing.
5873  *
5874  *	LOCKING:
5875  *	Inherited from caller.
5876  */
5877 void ata_dev_init(struct ata_device *dev)
5878 {
5879 	struct ata_link *link = ata_dev_phys_link(dev);
5880 	struct ata_port *ap = link->ap;
5881 	unsigned long flags;
5882 
5883 	/* SATA spd limit is bound to the attached device, reset together */
5884 	link->sata_spd_limit = link->hw_sata_spd_limit;
5885 	link->sata_spd = 0;
5886 
5887 	/* High bits of dev->flags are used to record warm plug
5888 	 * requests which occur asynchronously.  Synchronize using
5889 	 * host lock.
5890 	 */
5891 	spin_lock_irqsave(ap->lock, flags);
5892 	dev->flags &= ~ATA_DFLAG_INIT_MASK;
5893 	dev->horkage = 0;
5894 	spin_unlock_irqrestore(ap->lock, flags);
5895 
5896 	memset((void *)dev + ATA_DEVICE_CLEAR_BEGIN, 0,
5897 	       ATA_DEVICE_CLEAR_END - ATA_DEVICE_CLEAR_BEGIN);
5898 	dev->pio_mask = UINT_MAX;
5899 	dev->mwdma_mask = UINT_MAX;
5900 	dev->udma_mask = UINT_MAX;
5901 }
5902 
5903 /**
5904  *	ata_link_init - Initialize an ata_link structure
5905  *	@ap: ATA port link is attached to
5906  *	@link: Link structure to initialize
5907  *	@pmp: Port multiplier port number
5908  *
5909  *	Initialize @link.
5910  *
5911  *	LOCKING:
5912  *	Kernel thread context (may sleep)
5913  */
5914 void ata_link_init(struct ata_port *ap, struct ata_link *link, int pmp)
5915 {
5916 	int i;
5917 
5918 	/* clear everything except for devices */
5919 	memset((void *)link + ATA_LINK_CLEAR_BEGIN, 0,
5920 	       ATA_LINK_CLEAR_END - ATA_LINK_CLEAR_BEGIN);
5921 
5922 	link->ap = ap;
5923 	link->pmp = pmp;
5924 	link->active_tag = ATA_TAG_POISON;
5925 	link->hw_sata_spd_limit = UINT_MAX;
5926 
5927 	/* can't use iterator, ap isn't initialized yet */
5928 	for (i = 0; i < ATA_MAX_DEVICES; i++) {
5929 		struct ata_device *dev = &link->device[i];
5930 
5931 		dev->link = link;
5932 		dev->devno = dev - link->device;
5933 #ifdef CONFIG_ATA_ACPI
5934 		dev->gtf_filter = ata_acpi_gtf_filter;
5935 #endif
5936 		ata_dev_init(dev);
5937 	}
5938 }
5939 
5940 /**
5941  *	sata_link_init_spd - Initialize link->sata_spd_limit
5942  *	@link: Link to configure sata_spd_limit for
5943  *
5944  *	Initialize @link->[hw_]sata_spd_limit to the currently
5945  *	configured value.
5946  *
5947  *	LOCKING:
5948  *	Kernel thread context (may sleep).
5949  *
5950  *	RETURNS:
5951  *	0 on success, -errno on failure.
5952  */
5953 int sata_link_init_spd(struct ata_link *link)
5954 {
5955 	u8 spd;
5956 	int rc;
5957 
5958 	rc = sata_scr_read(link, SCR_CONTROL, &link->saved_scontrol);
5959 	if (rc)
5960 		return rc;
5961 
5962 	spd = (link->saved_scontrol >> 4) & 0xf;
5963 	if (spd)
5964 		link->hw_sata_spd_limit &= (1 << spd) - 1;
5965 
5966 	ata_force_link_limits(link);
5967 
5968 	link->sata_spd_limit = link->hw_sata_spd_limit;
5969 
5970 	return 0;
5971 }
5972 
5973 /**
5974  *	ata_port_alloc - allocate and initialize basic ATA port resources
5975  *	@host: ATA host this allocated port belongs to
5976  *
5977  *	Allocate and initialize basic ATA port resources.
5978  *
5979  *	RETURNS:
5980  *	Allocate ATA port on success, NULL on failure.
5981  *
5982  *	LOCKING:
5983  *	Inherited from calling layer (may sleep).
5984  */
5985 struct ata_port *ata_port_alloc(struct ata_host *host)
5986 {
5987 	struct ata_port *ap;
5988 
5989 	DPRINTK("ENTER\n");
5990 
5991 	ap = kzalloc(sizeof(*ap), GFP_KERNEL);
5992 	if (!ap)
5993 		return NULL;
5994 
5995 	ap->pflags |= ATA_PFLAG_INITIALIZING | ATA_PFLAG_FROZEN;
5996 	ap->lock = &host->lock;
5997 	ap->print_id = -1;
5998 	ap->local_port_no = -1;
5999 	ap->host = host;
6000 	ap->dev = host->dev;
6001 
6002 #if defined(ATA_VERBOSE_DEBUG)
6003 	/* turn on all debugging levels */
6004 	ap->msg_enable = 0x00FF;
6005 #elif defined(ATA_DEBUG)
6006 	ap->msg_enable = ATA_MSG_DRV | ATA_MSG_INFO | ATA_MSG_CTL | ATA_MSG_WARN | ATA_MSG_ERR;
6007 #else
6008 	ap->msg_enable = ATA_MSG_DRV | ATA_MSG_ERR | ATA_MSG_WARN;
6009 #endif
6010 
6011 	mutex_init(&ap->scsi_scan_mutex);
6012 	INIT_DELAYED_WORK(&ap->hotplug_task, ata_scsi_hotplug);
6013 	INIT_WORK(&ap->scsi_rescan_task, ata_scsi_dev_rescan);
6014 	INIT_LIST_HEAD(&ap->eh_done_q);
6015 	init_waitqueue_head(&ap->eh_wait_q);
6016 	init_completion(&ap->park_req_pending);
6017 	timer_setup(&ap->fastdrain_timer, ata_eh_fastdrain_timerfn,
6018 		    TIMER_DEFERRABLE);
6019 
6020 	ap->cbl = ATA_CBL_NONE;
6021 
6022 	ata_link_init(ap, &ap->link, 0);
6023 
6024 #ifdef ATA_IRQ_TRAP
6025 	ap->stats.unhandled_irq = 1;
6026 	ap->stats.idle_irq = 1;
6027 #endif
6028 	ata_sff_port_init(ap);
6029 
6030 	return ap;
6031 }
6032 
6033 static void ata_devres_release(struct device *gendev, void *res)
6034 {
6035 	struct ata_host *host = dev_get_drvdata(gendev);
6036 	int i;
6037 
6038 	for (i = 0; i < host->n_ports; i++) {
6039 		struct ata_port *ap = host->ports[i];
6040 
6041 		if (!ap)
6042 			continue;
6043 
6044 		if (ap->scsi_host)
6045 			scsi_host_put(ap->scsi_host);
6046 
6047 	}
6048 
6049 	dev_set_drvdata(gendev, NULL);
6050 	ata_host_put(host);
6051 }
6052 
6053 static void ata_host_release(struct kref *kref)
6054 {
6055 	struct ata_host *host = container_of(kref, struct ata_host, kref);
6056 	int i;
6057 
6058 	for (i = 0; i < host->n_ports; i++) {
6059 		struct ata_port *ap = host->ports[i];
6060 
6061 		kfree(ap->pmp_link);
6062 		kfree(ap->slave_link);
6063 		kfree(ap);
6064 		host->ports[i] = NULL;
6065 	}
6066 	kfree(host);
6067 }
6068 
6069 void ata_host_get(struct ata_host *host)
6070 {
6071 	kref_get(&host->kref);
6072 }
6073 
6074 void ata_host_put(struct ata_host *host)
6075 {
6076 	kref_put(&host->kref, ata_host_release);
6077 }
6078 
6079 /**
6080  *	ata_host_alloc - allocate and init basic ATA host resources
6081  *	@dev: generic device this host is associated with
6082  *	@max_ports: maximum number of ATA ports associated with this host
6083  *
6084  *	Allocate and initialize basic ATA host resources.  LLD calls
6085  *	this function to allocate a host, initializes it fully and
6086  *	attaches it using ata_host_register().
6087  *
6088  *	@max_ports ports are allocated and host->n_ports is
6089  *	initialized to @max_ports.  The caller is allowed to decrease
6090  *	host->n_ports before calling ata_host_register().  The unused
6091  *	ports will be automatically freed on registration.
6092  *
6093  *	RETURNS:
6094  *	Allocate ATA host on success, NULL on failure.
6095  *
6096  *	LOCKING:
6097  *	Inherited from calling layer (may sleep).
6098  */
6099 struct ata_host *ata_host_alloc(struct device *dev, int max_ports)
6100 {
6101 	struct ata_host *host;
6102 	size_t sz;
6103 	int i;
6104 	void *dr;
6105 
6106 	DPRINTK("ENTER\n");
6107 
6108 	/* alloc a container for our list of ATA ports (buses) */
6109 	sz = sizeof(struct ata_host) + (max_ports + 1) * sizeof(void *);
6110 	host = kzalloc(sz, GFP_KERNEL);
6111 	if (!host)
6112 		return NULL;
6113 
6114 	if (!devres_open_group(dev, NULL, GFP_KERNEL))
6115 		goto err_free;
6116 
6117 	dr = devres_alloc(ata_devres_release, 0, GFP_KERNEL);
6118 	if (!dr)
6119 		goto err_out;
6120 
6121 	devres_add(dev, dr);
6122 	dev_set_drvdata(dev, host);
6123 
6124 	spin_lock_init(&host->lock);
6125 	mutex_init(&host->eh_mutex);
6126 	host->dev = dev;
6127 	host->n_ports = max_ports;
6128 	kref_init(&host->kref);
6129 
6130 	/* allocate ports bound to this host */
6131 	for (i = 0; i < max_ports; i++) {
6132 		struct ata_port *ap;
6133 
6134 		ap = ata_port_alloc(host);
6135 		if (!ap)
6136 			goto err_out;
6137 
6138 		ap->port_no = i;
6139 		host->ports[i] = ap;
6140 	}
6141 
6142 	devres_remove_group(dev, NULL);
6143 	return host;
6144 
6145  err_out:
6146 	devres_release_group(dev, NULL);
6147  err_free:
6148 	kfree(host);
6149 	return NULL;
6150 }
6151 
6152 /**
6153  *	ata_host_alloc_pinfo - alloc host and init with port_info array
6154  *	@dev: generic device this host is associated with
6155  *	@ppi: array of ATA port_info to initialize host with
6156  *	@n_ports: number of ATA ports attached to this host
6157  *
6158  *	Allocate ATA host and initialize with info from @ppi.  If NULL
6159  *	terminated, @ppi may contain fewer entries than @n_ports.  The
6160  *	last entry will be used for the remaining ports.
6161  *
6162  *	RETURNS:
6163  *	Allocate ATA host on success, NULL on failure.
6164  *
6165  *	LOCKING:
6166  *	Inherited from calling layer (may sleep).
6167  */
6168 struct ata_host *ata_host_alloc_pinfo(struct device *dev,
6169 				      const struct ata_port_info * const * ppi,
6170 				      int n_ports)
6171 {
6172 	const struct ata_port_info *pi;
6173 	struct ata_host *host;
6174 	int i, j;
6175 
6176 	host = ata_host_alloc(dev, n_ports);
6177 	if (!host)
6178 		return NULL;
6179 
6180 	for (i = 0, j = 0, pi = NULL; i < host->n_ports; i++) {
6181 		struct ata_port *ap = host->ports[i];
6182 
6183 		if (ppi[j])
6184 			pi = ppi[j++];
6185 
6186 		ap->pio_mask = pi->pio_mask;
6187 		ap->mwdma_mask = pi->mwdma_mask;
6188 		ap->udma_mask = pi->udma_mask;
6189 		ap->flags |= pi->flags;
6190 		ap->link.flags |= pi->link_flags;
6191 		ap->ops = pi->port_ops;
6192 
6193 		if (!host->ops && (pi->port_ops != &ata_dummy_port_ops))
6194 			host->ops = pi->port_ops;
6195 	}
6196 
6197 	return host;
6198 }
6199 
6200 /**
6201  *	ata_slave_link_init - initialize slave link
6202  *	@ap: port to initialize slave link for
6203  *
6204  *	Create and initialize slave link for @ap.  This enables slave
6205  *	link handling on the port.
6206  *
6207  *	In libata, a port contains links and a link contains devices.
6208  *	There is single host link but if a PMP is attached to it,
6209  *	there can be multiple fan-out links.  On SATA, there's usually
6210  *	a single device connected to a link but PATA and SATA
6211  *	controllers emulating TF based interface can have two - master
6212  *	and slave.
6213  *
6214  *	However, there are a few controllers which don't fit into this
6215  *	abstraction too well - SATA controllers which emulate TF
6216  *	interface with both master and slave devices but also have
6217  *	separate SCR register sets for each device.  These controllers
6218  *	need separate links for physical link handling
6219  *	(e.g. onlineness, link speed) but should be treated like a
6220  *	traditional M/S controller for everything else (e.g. command
6221  *	issue, softreset).
6222  *
6223  *	slave_link is libata's way of handling this class of
6224  *	controllers without impacting core layer too much.  For
6225  *	anything other than physical link handling, the default host
6226  *	link is used for both master and slave.  For physical link
6227  *	handling, separate @ap->slave_link is used.  All dirty details
6228  *	are implemented inside libata core layer.  From LLD's POV, the
6229  *	only difference is that prereset, hardreset and postreset are
6230  *	called once more for the slave link, so the reset sequence
6231  *	looks like the following.
6232  *
6233  *	prereset(M) -> prereset(S) -> hardreset(M) -> hardreset(S) ->
6234  *	softreset(M) -> postreset(M) -> postreset(S)
6235  *
6236  *	Note that softreset is called only for the master.  Softreset
6237  *	resets both M/S by definition, so SRST on master should handle
6238  *	both (the standard method will work just fine).
6239  *
6240  *	LOCKING:
6241  *	Should be called before host is registered.
6242  *
6243  *	RETURNS:
6244  *	0 on success, -errno on failure.
6245  */
6246 int ata_slave_link_init(struct ata_port *ap)
6247 {
6248 	struct ata_link *link;
6249 
6250 	WARN_ON(ap->slave_link);
6251 	WARN_ON(ap->flags & ATA_FLAG_PMP);
6252 
6253 	link = kzalloc(sizeof(*link), GFP_KERNEL);
6254 	if (!link)
6255 		return -ENOMEM;
6256 
6257 	ata_link_init(ap, link, 1);
6258 	ap->slave_link = link;
6259 	return 0;
6260 }
6261 
6262 static void ata_host_stop(struct device *gendev, void *res)
6263 {
6264 	struct ata_host *host = dev_get_drvdata(gendev);
6265 	int i;
6266 
6267 	WARN_ON(!(host->flags & ATA_HOST_STARTED));
6268 
6269 	for (i = 0; i < host->n_ports; i++) {
6270 		struct ata_port *ap = host->ports[i];
6271 
6272 		if (ap->ops->port_stop)
6273 			ap->ops->port_stop(ap);
6274 	}
6275 
6276 	if (host->ops->host_stop)
6277 		host->ops->host_stop(host);
6278 }
6279 
6280 /**
6281  *	ata_finalize_port_ops - finalize ata_port_operations
6282  *	@ops: ata_port_operations to finalize
6283  *
6284  *	An ata_port_operations can inherit from another ops and that
6285  *	ops can again inherit from another.  This can go on as many
6286  *	times as necessary as long as there is no loop in the
6287  *	inheritance chain.
6288  *
6289  *	Ops tables are finalized when the host is started.  NULL or
6290  *	unspecified entries are inherited from the closet ancestor
6291  *	which has the method and the entry is populated with it.
6292  *	After finalization, the ops table directly points to all the
6293  *	methods and ->inherits is no longer necessary and cleared.
6294  *
6295  *	Using ATA_OP_NULL, inheriting ops can force a method to NULL.
6296  *
6297  *	LOCKING:
6298  *	None.
6299  */
6300 static void ata_finalize_port_ops(struct ata_port_operations *ops)
6301 {
6302 	static DEFINE_SPINLOCK(lock);
6303 	const struct ata_port_operations *cur;
6304 	void **begin = (void **)ops;
6305 	void **end = (void **)&ops->inherits;
6306 	void **pp;
6307 
6308 	if (!ops || !ops->inherits)
6309 		return;
6310 
6311 	spin_lock(&lock);
6312 
6313 	for (cur = ops->inherits; cur; cur = cur->inherits) {
6314 		void **inherit = (void **)cur;
6315 
6316 		for (pp = begin; pp < end; pp++, inherit++)
6317 			if (!*pp)
6318 				*pp = *inherit;
6319 	}
6320 
6321 	for (pp = begin; pp < end; pp++)
6322 		if (IS_ERR(*pp))
6323 			*pp = NULL;
6324 
6325 	ops->inherits = NULL;
6326 
6327 	spin_unlock(&lock);
6328 }
6329 
6330 /**
6331  *	ata_host_start - start and freeze ports of an ATA host
6332  *	@host: ATA host to start ports for
6333  *
6334  *	Start and then freeze ports of @host.  Started status is
6335  *	recorded in host->flags, so this function can be called
6336  *	multiple times.  Ports are guaranteed to get started only
6337  *	once.  If host->ops isn't initialized yet, its set to the
6338  *	first non-dummy port ops.
6339  *
6340  *	LOCKING:
6341  *	Inherited from calling layer (may sleep).
6342  *
6343  *	RETURNS:
6344  *	0 if all ports are started successfully, -errno otherwise.
6345  */
6346 int ata_host_start(struct ata_host *host)
6347 {
6348 	int have_stop = 0;
6349 	void *start_dr = NULL;
6350 	int i, rc;
6351 
6352 	if (host->flags & ATA_HOST_STARTED)
6353 		return 0;
6354 
6355 	ata_finalize_port_ops(host->ops);
6356 
6357 	for (i = 0; i < host->n_ports; i++) {
6358 		struct ata_port *ap = host->ports[i];
6359 
6360 		ata_finalize_port_ops(ap->ops);
6361 
6362 		if (!host->ops && !ata_port_is_dummy(ap))
6363 			host->ops = ap->ops;
6364 
6365 		if (ap->ops->port_stop)
6366 			have_stop = 1;
6367 	}
6368 
6369 	if (host->ops->host_stop)
6370 		have_stop = 1;
6371 
6372 	if (have_stop) {
6373 		start_dr = devres_alloc(ata_host_stop, 0, GFP_KERNEL);
6374 		if (!start_dr)
6375 			return -ENOMEM;
6376 	}
6377 
6378 	for (i = 0; i < host->n_ports; i++) {
6379 		struct ata_port *ap = host->ports[i];
6380 
6381 		if (ap->ops->port_start) {
6382 			rc = ap->ops->port_start(ap);
6383 			if (rc) {
6384 				if (rc != -ENODEV)
6385 					dev_err(host->dev,
6386 						"failed to start port %d (errno=%d)\n",
6387 						i, rc);
6388 				goto err_out;
6389 			}
6390 		}
6391 		ata_eh_freeze_port(ap);
6392 	}
6393 
6394 	if (start_dr)
6395 		devres_add(host->dev, start_dr);
6396 	host->flags |= ATA_HOST_STARTED;
6397 	return 0;
6398 
6399  err_out:
6400 	while (--i >= 0) {
6401 		struct ata_port *ap = host->ports[i];
6402 
6403 		if (ap->ops->port_stop)
6404 			ap->ops->port_stop(ap);
6405 	}
6406 	devres_free(start_dr);
6407 	return rc;
6408 }
6409 
6410 /**
6411  *	ata_sas_host_init - Initialize a host struct for sas (ipr, libsas)
6412  *	@host:	host to initialize
6413  *	@dev:	device host is attached to
6414  *	@ops:	port_ops
6415  *
6416  */
6417 void ata_host_init(struct ata_host *host, struct device *dev,
6418 		   struct ata_port_operations *ops)
6419 {
6420 	spin_lock_init(&host->lock);
6421 	mutex_init(&host->eh_mutex);
6422 	host->n_tags = ATA_MAX_QUEUE;
6423 	host->dev = dev;
6424 	host->ops = ops;
6425 	kref_init(&host->kref);
6426 }
6427 
6428 void __ata_port_probe(struct ata_port *ap)
6429 {
6430 	struct ata_eh_info *ehi = &ap->link.eh_info;
6431 	unsigned long flags;
6432 
6433 	/* kick EH for boot probing */
6434 	spin_lock_irqsave(ap->lock, flags);
6435 
6436 	ehi->probe_mask |= ATA_ALL_DEVICES;
6437 	ehi->action |= ATA_EH_RESET;
6438 	ehi->flags |= ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET;
6439 
6440 	ap->pflags &= ~ATA_PFLAG_INITIALIZING;
6441 	ap->pflags |= ATA_PFLAG_LOADING;
6442 	ata_port_schedule_eh(ap);
6443 
6444 	spin_unlock_irqrestore(ap->lock, flags);
6445 }
6446 
6447 int ata_port_probe(struct ata_port *ap)
6448 {
6449 	int rc = 0;
6450 
6451 	if (ap->ops->error_handler) {
6452 		__ata_port_probe(ap);
6453 		ata_port_wait_eh(ap);
6454 	} else {
6455 		DPRINTK("ata%u: bus probe begin\n", ap->print_id);
6456 		rc = ata_bus_probe(ap);
6457 		DPRINTK("ata%u: bus probe end\n", ap->print_id);
6458 	}
6459 	return rc;
6460 }
6461 
6462 
6463 static void async_port_probe(void *data, async_cookie_t cookie)
6464 {
6465 	struct ata_port *ap = data;
6466 
6467 	/*
6468 	 * If we're not allowed to scan this host in parallel,
6469 	 * we need to wait until all previous scans have completed
6470 	 * before going further.
6471 	 * Jeff Garzik says this is only within a controller, so we
6472 	 * don't need to wait for port 0, only for later ports.
6473 	 */
6474 	if (!(ap->host->flags & ATA_HOST_PARALLEL_SCAN) && ap->port_no != 0)
6475 		async_synchronize_cookie(cookie);
6476 
6477 	(void)ata_port_probe(ap);
6478 
6479 	/* in order to keep device order, we need to synchronize at this point */
6480 	async_synchronize_cookie(cookie);
6481 
6482 	ata_scsi_scan_host(ap, 1);
6483 }
6484 
6485 /**
6486  *	ata_host_register - register initialized ATA host
6487  *	@host: ATA host to register
6488  *	@sht: template for SCSI host
6489  *
6490  *	Register initialized ATA host.  @host is allocated using
6491  *	ata_host_alloc() and fully initialized by LLD.  This function
6492  *	starts ports, registers @host with ATA and SCSI layers and
6493  *	probe registered devices.
6494  *
6495  *	LOCKING:
6496  *	Inherited from calling layer (may sleep).
6497  *
6498  *	RETURNS:
6499  *	0 on success, -errno otherwise.
6500  */
6501 int ata_host_register(struct ata_host *host, struct scsi_host_template *sht)
6502 {
6503 	int i, rc;
6504 
6505 	host->n_tags = clamp(sht->can_queue, 1, ATA_MAX_QUEUE);
6506 
6507 	/* host must have been started */
6508 	if (!(host->flags & ATA_HOST_STARTED)) {
6509 		dev_err(host->dev, "BUG: trying to register unstarted host\n");
6510 		WARN_ON(1);
6511 		return -EINVAL;
6512 	}
6513 
6514 	/* Blow away unused ports.  This happens when LLD can't
6515 	 * determine the exact number of ports to allocate at
6516 	 * allocation time.
6517 	 */
6518 	for (i = host->n_ports; host->ports[i]; i++)
6519 		kfree(host->ports[i]);
6520 
6521 	/* give ports names and add SCSI hosts */
6522 	for (i = 0; i < host->n_ports; i++) {
6523 		host->ports[i]->print_id = atomic_inc_return(&ata_print_id);
6524 		host->ports[i]->local_port_no = i + 1;
6525 	}
6526 
6527 	/* Create associated sysfs transport objects  */
6528 	for (i = 0; i < host->n_ports; i++) {
6529 		rc = ata_tport_add(host->dev,host->ports[i]);
6530 		if (rc) {
6531 			goto err_tadd;
6532 		}
6533 	}
6534 
6535 	rc = ata_scsi_add_hosts(host, sht);
6536 	if (rc)
6537 		goto err_tadd;
6538 
6539 	/* set cable, sata_spd_limit and report */
6540 	for (i = 0; i < host->n_ports; i++) {
6541 		struct ata_port *ap = host->ports[i];
6542 		unsigned long xfer_mask;
6543 
6544 		/* set SATA cable type if still unset */
6545 		if (ap->cbl == ATA_CBL_NONE && (ap->flags & ATA_FLAG_SATA))
6546 			ap->cbl = ATA_CBL_SATA;
6547 
6548 		/* init sata_spd_limit to the current value */
6549 		sata_link_init_spd(&ap->link);
6550 		if (ap->slave_link)
6551 			sata_link_init_spd(ap->slave_link);
6552 
6553 		/* print per-port info to dmesg */
6554 		xfer_mask = ata_pack_xfermask(ap->pio_mask, ap->mwdma_mask,
6555 					      ap->udma_mask);
6556 
6557 		if (!ata_port_is_dummy(ap)) {
6558 			ata_port_info(ap, "%cATA max %s %s\n",
6559 				      (ap->flags & ATA_FLAG_SATA) ? 'S' : 'P',
6560 				      ata_mode_string(xfer_mask),
6561 				      ap->link.eh_info.desc);
6562 			ata_ehi_clear_desc(&ap->link.eh_info);
6563 		} else
6564 			ata_port_info(ap, "DUMMY\n");
6565 	}
6566 
6567 	/* perform each probe asynchronously */
6568 	for (i = 0; i < host->n_ports; i++) {
6569 		struct ata_port *ap = host->ports[i];
6570 		async_schedule(async_port_probe, ap);
6571 	}
6572 
6573 	return 0;
6574 
6575  err_tadd:
6576 	while (--i >= 0) {
6577 		ata_tport_delete(host->ports[i]);
6578 	}
6579 	return rc;
6580 
6581 }
6582 
6583 /**
6584  *	ata_host_activate - start host, request IRQ and register it
6585  *	@host: target ATA host
6586  *	@irq: IRQ to request
6587  *	@irq_handler: irq_handler used when requesting IRQ
6588  *	@irq_flags: irq_flags used when requesting IRQ
6589  *	@sht: scsi_host_template to use when registering the host
6590  *
6591  *	After allocating an ATA host and initializing it, most libata
6592  *	LLDs perform three steps to activate the host - start host,
6593  *	request IRQ and register it.  This helper takes necessary
6594  *	arguments and performs the three steps in one go.
6595  *
6596  *	An invalid IRQ skips the IRQ registration and expects the host to
6597  *	have set polling mode on the port. In this case, @irq_handler
6598  *	should be NULL.
6599  *
6600  *	LOCKING:
6601  *	Inherited from calling layer (may sleep).
6602  *
6603  *	RETURNS:
6604  *	0 on success, -errno otherwise.
6605  */
6606 int ata_host_activate(struct ata_host *host, int irq,
6607 		      irq_handler_t irq_handler, unsigned long irq_flags,
6608 		      struct scsi_host_template *sht)
6609 {
6610 	int i, rc;
6611 	char *irq_desc;
6612 
6613 	rc = ata_host_start(host);
6614 	if (rc)
6615 		return rc;
6616 
6617 	/* Special case for polling mode */
6618 	if (!irq) {
6619 		WARN_ON(irq_handler);
6620 		return ata_host_register(host, sht);
6621 	}
6622 
6623 	irq_desc = devm_kasprintf(host->dev, GFP_KERNEL, "%s[%s]",
6624 				  dev_driver_string(host->dev),
6625 				  dev_name(host->dev));
6626 	if (!irq_desc)
6627 		return -ENOMEM;
6628 
6629 	rc = devm_request_irq(host->dev, irq, irq_handler, irq_flags,
6630 			      irq_desc, host);
6631 	if (rc)
6632 		return rc;
6633 
6634 	for (i = 0; i < host->n_ports; i++)
6635 		ata_port_desc(host->ports[i], "irq %d", irq);
6636 
6637 	rc = ata_host_register(host, sht);
6638 	/* if failed, just free the IRQ and leave ports alone */
6639 	if (rc)
6640 		devm_free_irq(host->dev, irq, host);
6641 
6642 	return rc;
6643 }
6644 
6645 /**
6646  *	ata_port_detach - Detach ATA port in preparation of device removal
6647  *	@ap: ATA port to be detached
6648  *
6649  *	Detach all ATA devices and the associated SCSI devices of @ap;
6650  *	then, remove the associated SCSI host.  @ap is guaranteed to
6651  *	be quiescent on return from this function.
6652  *
6653  *	LOCKING:
6654  *	Kernel thread context (may sleep).
6655  */
6656 static void ata_port_detach(struct ata_port *ap)
6657 {
6658 	unsigned long flags;
6659 	struct ata_link *link;
6660 	struct ata_device *dev;
6661 
6662 	if (!ap->ops->error_handler)
6663 		goto skip_eh;
6664 
6665 	/* tell EH we're leaving & flush EH */
6666 	spin_lock_irqsave(ap->lock, flags);
6667 	ap->pflags |= ATA_PFLAG_UNLOADING;
6668 	ata_port_schedule_eh(ap);
6669 	spin_unlock_irqrestore(ap->lock, flags);
6670 
6671 	/* wait till EH commits suicide */
6672 	ata_port_wait_eh(ap);
6673 
6674 	/* it better be dead now */
6675 	WARN_ON(!(ap->pflags & ATA_PFLAG_UNLOADED));
6676 
6677 	cancel_delayed_work_sync(&ap->hotplug_task);
6678 
6679  skip_eh:
6680 	/* clean up zpodd on port removal */
6681 	ata_for_each_link(link, ap, HOST_FIRST) {
6682 		ata_for_each_dev(dev, link, ALL) {
6683 			if (zpodd_dev_enabled(dev))
6684 				zpodd_exit(dev);
6685 		}
6686 	}
6687 	if (ap->pmp_link) {
6688 		int i;
6689 		for (i = 0; i < SATA_PMP_MAX_PORTS; i++)
6690 			ata_tlink_delete(&ap->pmp_link[i]);
6691 	}
6692 	/* remove the associated SCSI host */
6693 	scsi_remove_host(ap->scsi_host);
6694 	ata_tport_delete(ap);
6695 }
6696 
6697 /**
6698  *	ata_host_detach - Detach all ports of an ATA host
6699  *	@host: Host to detach
6700  *
6701  *	Detach all ports of @host.
6702  *
6703  *	LOCKING:
6704  *	Kernel thread context (may sleep).
6705  */
6706 void ata_host_detach(struct ata_host *host)
6707 {
6708 	int i;
6709 
6710 	for (i = 0; i < host->n_ports; i++)
6711 		ata_port_detach(host->ports[i]);
6712 
6713 	/* the host is dead now, dissociate ACPI */
6714 	ata_acpi_dissociate(host);
6715 }
6716 
6717 #ifdef CONFIG_PCI
6718 
6719 /**
6720  *	ata_pci_remove_one - PCI layer callback for device removal
6721  *	@pdev: PCI device that was removed
6722  *
6723  *	PCI layer indicates to libata via this hook that hot-unplug or
6724  *	module unload event has occurred.  Detach all ports.  Resource
6725  *	release is handled via devres.
6726  *
6727  *	LOCKING:
6728  *	Inherited from PCI layer (may sleep).
6729  */
6730 void ata_pci_remove_one(struct pci_dev *pdev)
6731 {
6732 	struct ata_host *host = pci_get_drvdata(pdev);
6733 
6734 	ata_host_detach(host);
6735 }
6736 
6737 /* move to PCI subsystem */
6738 int pci_test_config_bits(struct pci_dev *pdev, const struct pci_bits *bits)
6739 {
6740 	unsigned long tmp = 0;
6741 
6742 	switch (bits->width) {
6743 	case 1: {
6744 		u8 tmp8 = 0;
6745 		pci_read_config_byte(pdev, bits->reg, &tmp8);
6746 		tmp = tmp8;
6747 		break;
6748 	}
6749 	case 2: {
6750 		u16 tmp16 = 0;
6751 		pci_read_config_word(pdev, bits->reg, &tmp16);
6752 		tmp = tmp16;
6753 		break;
6754 	}
6755 	case 4: {
6756 		u32 tmp32 = 0;
6757 		pci_read_config_dword(pdev, bits->reg, &tmp32);
6758 		tmp = tmp32;
6759 		break;
6760 	}
6761 
6762 	default:
6763 		return -EINVAL;
6764 	}
6765 
6766 	tmp &= bits->mask;
6767 
6768 	return (tmp == bits->val) ? 1 : 0;
6769 }
6770 
6771 #ifdef CONFIG_PM
6772 void ata_pci_device_do_suspend(struct pci_dev *pdev, pm_message_t mesg)
6773 {
6774 	pci_save_state(pdev);
6775 	pci_disable_device(pdev);
6776 
6777 	if (mesg.event & PM_EVENT_SLEEP)
6778 		pci_set_power_state(pdev, PCI_D3hot);
6779 }
6780 
6781 int ata_pci_device_do_resume(struct pci_dev *pdev)
6782 {
6783 	int rc;
6784 
6785 	pci_set_power_state(pdev, PCI_D0);
6786 	pci_restore_state(pdev);
6787 
6788 	rc = pcim_enable_device(pdev);
6789 	if (rc) {
6790 		dev_err(&pdev->dev,
6791 			"failed to enable device after resume (%d)\n", rc);
6792 		return rc;
6793 	}
6794 
6795 	pci_set_master(pdev);
6796 	return 0;
6797 }
6798 
6799 int ata_pci_device_suspend(struct pci_dev *pdev, pm_message_t mesg)
6800 {
6801 	struct ata_host *host = pci_get_drvdata(pdev);
6802 	int rc = 0;
6803 
6804 	rc = ata_host_suspend(host, mesg);
6805 	if (rc)
6806 		return rc;
6807 
6808 	ata_pci_device_do_suspend(pdev, mesg);
6809 
6810 	return 0;
6811 }
6812 
6813 int ata_pci_device_resume(struct pci_dev *pdev)
6814 {
6815 	struct ata_host *host = pci_get_drvdata(pdev);
6816 	int rc;
6817 
6818 	rc = ata_pci_device_do_resume(pdev);
6819 	if (rc == 0)
6820 		ata_host_resume(host);
6821 	return rc;
6822 }
6823 #endif /* CONFIG_PM */
6824 
6825 #endif /* CONFIG_PCI */
6826 
6827 /**
6828  *	ata_platform_remove_one - Platform layer callback for device removal
6829  *	@pdev: Platform device that was removed
6830  *
6831  *	Platform layer indicates to libata via this hook that hot-unplug or
6832  *	module unload event has occurred.  Detach all ports.  Resource
6833  *	release is handled via devres.
6834  *
6835  *	LOCKING:
6836  *	Inherited from platform layer (may sleep).
6837  */
6838 int ata_platform_remove_one(struct platform_device *pdev)
6839 {
6840 	struct ata_host *host = platform_get_drvdata(pdev);
6841 
6842 	ata_host_detach(host);
6843 
6844 	return 0;
6845 }
6846 
6847 static int __init ata_parse_force_one(char **cur,
6848 				      struct ata_force_ent *force_ent,
6849 				      const char **reason)
6850 {
6851 	static const struct ata_force_param force_tbl[] __initconst = {
6852 		{ "40c",	.cbl		= ATA_CBL_PATA40 },
6853 		{ "80c",	.cbl		= ATA_CBL_PATA80 },
6854 		{ "short40c",	.cbl		= ATA_CBL_PATA40_SHORT },
6855 		{ "unk",	.cbl		= ATA_CBL_PATA_UNK },
6856 		{ "ign",	.cbl		= ATA_CBL_PATA_IGN },
6857 		{ "sata",	.cbl		= ATA_CBL_SATA },
6858 		{ "1.5Gbps",	.spd_limit	= 1 },
6859 		{ "3.0Gbps",	.spd_limit	= 2 },
6860 		{ "noncq",	.horkage_on	= ATA_HORKAGE_NONCQ },
6861 		{ "ncq",	.horkage_off	= ATA_HORKAGE_NONCQ },
6862 		{ "noncqtrim",	.horkage_on	= ATA_HORKAGE_NO_NCQ_TRIM },
6863 		{ "ncqtrim",	.horkage_off	= ATA_HORKAGE_NO_NCQ_TRIM },
6864 		{ "dump_id",	.horkage_on	= ATA_HORKAGE_DUMP_ID },
6865 		{ "pio0",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 0) },
6866 		{ "pio1",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 1) },
6867 		{ "pio2",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 2) },
6868 		{ "pio3",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 3) },
6869 		{ "pio4",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 4) },
6870 		{ "pio5",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 5) },
6871 		{ "pio6",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 6) },
6872 		{ "mwdma0",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 0) },
6873 		{ "mwdma1",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 1) },
6874 		{ "mwdma2",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 2) },
6875 		{ "mwdma3",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 3) },
6876 		{ "mwdma4",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 4) },
6877 		{ "udma0",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 0) },
6878 		{ "udma16",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 0) },
6879 		{ "udma/16",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 0) },
6880 		{ "udma1",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 1) },
6881 		{ "udma25",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 1) },
6882 		{ "udma/25",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 1) },
6883 		{ "udma2",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 2) },
6884 		{ "udma33",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 2) },
6885 		{ "udma/33",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 2) },
6886 		{ "udma3",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 3) },
6887 		{ "udma44",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 3) },
6888 		{ "udma/44",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 3) },
6889 		{ "udma4",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 4) },
6890 		{ "udma66",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 4) },
6891 		{ "udma/66",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 4) },
6892 		{ "udma5",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 5) },
6893 		{ "udma100",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 5) },
6894 		{ "udma/100",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 5) },
6895 		{ "udma6",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 6) },
6896 		{ "udma133",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 6) },
6897 		{ "udma/133",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 6) },
6898 		{ "udma7",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 7) },
6899 		{ "nohrst",	.lflags		= ATA_LFLAG_NO_HRST },
6900 		{ "nosrst",	.lflags		= ATA_LFLAG_NO_SRST },
6901 		{ "norst",	.lflags		= ATA_LFLAG_NO_HRST | ATA_LFLAG_NO_SRST },
6902 		{ "rstonce",	.lflags		= ATA_LFLAG_RST_ONCE },
6903 		{ "atapi_dmadir", .horkage_on	= ATA_HORKAGE_ATAPI_DMADIR },
6904 		{ "disable",	.horkage_on	= ATA_HORKAGE_DISABLE },
6905 	};
6906 	char *start = *cur, *p = *cur;
6907 	char *id, *val, *endp;
6908 	const struct ata_force_param *match_fp = NULL;
6909 	int nr_matches = 0, i;
6910 
6911 	/* find where this param ends and update *cur */
6912 	while (*p != '\0' && *p != ',')
6913 		p++;
6914 
6915 	if (*p == '\0')
6916 		*cur = p;
6917 	else
6918 		*cur = p + 1;
6919 
6920 	*p = '\0';
6921 
6922 	/* parse */
6923 	p = strchr(start, ':');
6924 	if (!p) {
6925 		val = strstrip(start);
6926 		goto parse_val;
6927 	}
6928 	*p = '\0';
6929 
6930 	id = strstrip(start);
6931 	val = strstrip(p + 1);
6932 
6933 	/* parse id */
6934 	p = strchr(id, '.');
6935 	if (p) {
6936 		*p++ = '\0';
6937 		force_ent->device = simple_strtoul(p, &endp, 10);
6938 		if (p == endp || *endp != '\0') {
6939 			*reason = "invalid device";
6940 			return -EINVAL;
6941 		}
6942 	}
6943 
6944 	force_ent->port = simple_strtoul(id, &endp, 10);
6945 	if (id == endp || *endp != '\0') {
6946 		*reason = "invalid port/link";
6947 		return -EINVAL;
6948 	}
6949 
6950  parse_val:
6951 	/* parse val, allow shortcuts so that both 1.5 and 1.5Gbps work */
6952 	for (i = 0; i < ARRAY_SIZE(force_tbl); i++) {
6953 		const struct ata_force_param *fp = &force_tbl[i];
6954 
6955 		if (strncasecmp(val, fp->name, strlen(val)))
6956 			continue;
6957 
6958 		nr_matches++;
6959 		match_fp = fp;
6960 
6961 		if (strcasecmp(val, fp->name) == 0) {
6962 			nr_matches = 1;
6963 			break;
6964 		}
6965 	}
6966 
6967 	if (!nr_matches) {
6968 		*reason = "unknown value";
6969 		return -EINVAL;
6970 	}
6971 	if (nr_matches > 1) {
6972 		*reason = "ambiguous value";
6973 		return -EINVAL;
6974 	}
6975 
6976 	force_ent->param = *match_fp;
6977 
6978 	return 0;
6979 }
6980 
6981 static void __init ata_parse_force_param(void)
6982 {
6983 	int idx = 0, size = 1;
6984 	int last_port = -1, last_device = -1;
6985 	char *p, *cur, *next;
6986 
6987 	/* calculate maximum number of params and allocate force_tbl */
6988 	for (p = ata_force_param_buf; *p; p++)
6989 		if (*p == ',')
6990 			size++;
6991 
6992 	ata_force_tbl = kcalloc(size, sizeof(ata_force_tbl[0]), GFP_KERNEL);
6993 	if (!ata_force_tbl) {
6994 		printk(KERN_WARNING "ata: failed to extend force table, "
6995 		       "libata.force ignored\n");
6996 		return;
6997 	}
6998 
6999 	/* parse and populate the table */
7000 	for (cur = ata_force_param_buf; *cur != '\0'; cur = next) {
7001 		const char *reason = "";
7002 		struct ata_force_ent te = { .port = -1, .device = -1 };
7003 
7004 		next = cur;
7005 		if (ata_parse_force_one(&next, &te, &reason)) {
7006 			printk(KERN_WARNING "ata: failed to parse force "
7007 			       "parameter \"%s\" (%s)\n",
7008 			       cur, reason);
7009 			continue;
7010 		}
7011 
7012 		if (te.port == -1) {
7013 			te.port = last_port;
7014 			te.device = last_device;
7015 		}
7016 
7017 		ata_force_tbl[idx++] = te;
7018 
7019 		last_port = te.port;
7020 		last_device = te.device;
7021 	}
7022 
7023 	ata_force_tbl_size = idx;
7024 }
7025 
7026 static int __init ata_init(void)
7027 {
7028 	int rc;
7029 
7030 	ata_parse_force_param();
7031 
7032 	rc = ata_sff_init();
7033 	if (rc) {
7034 		kfree(ata_force_tbl);
7035 		return rc;
7036 	}
7037 
7038 	libata_transport_init();
7039 	ata_scsi_transport_template = ata_attach_transport();
7040 	if (!ata_scsi_transport_template) {
7041 		ata_sff_exit();
7042 		rc = -ENOMEM;
7043 		goto err_out;
7044 	}
7045 
7046 	printk(KERN_DEBUG "libata version " DRV_VERSION " loaded.\n");
7047 	return 0;
7048 
7049 err_out:
7050 	return rc;
7051 }
7052 
7053 static void __exit ata_exit(void)
7054 {
7055 	ata_release_transport(ata_scsi_transport_template);
7056 	libata_transport_exit();
7057 	ata_sff_exit();
7058 	kfree(ata_force_tbl);
7059 }
7060 
7061 subsys_initcall(ata_init);
7062 module_exit(ata_exit);
7063 
7064 static DEFINE_RATELIMIT_STATE(ratelimit, HZ / 5, 1);
7065 
7066 int ata_ratelimit(void)
7067 {
7068 	return __ratelimit(&ratelimit);
7069 }
7070 
7071 /**
7072  *	ata_msleep - ATA EH owner aware msleep
7073  *	@ap: ATA port to attribute the sleep to
7074  *	@msecs: duration to sleep in milliseconds
7075  *
7076  *	Sleeps @msecs.  If the current task is owner of @ap's EH, the
7077  *	ownership is released before going to sleep and reacquired
7078  *	after the sleep is complete.  IOW, other ports sharing the
7079  *	@ap->host will be allowed to own the EH while this task is
7080  *	sleeping.
7081  *
7082  *	LOCKING:
7083  *	Might sleep.
7084  */
7085 void ata_msleep(struct ata_port *ap, unsigned int msecs)
7086 {
7087 	bool owns_eh = ap && ap->host->eh_owner == current;
7088 
7089 	if (owns_eh)
7090 		ata_eh_release(ap);
7091 
7092 	if (msecs < 20) {
7093 		unsigned long usecs = msecs * USEC_PER_MSEC;
7094 		usleep_range(usecs, usecs + 50);
7095 	} else {
7096 		msleep(msecs);
7097 	}
7098 
7099 	if (owns_eh)
7100 		ata_eh_acquire(ap);
7101 }
7102 
7103 /**
7104  *	ata_wait_register - wait until register value changes
7105  *	@ap: ATA port to wait register for, can be NULL
7106  *	@reg: IO-mapped register
7107  *	@mask: Mask to apply to read register value
7108  *	@val: Wait condition
7109  *	@interval: polling interval in milliseconds
7110  *	@timeout: timeout in milliseconds
7111  *
7112  *	Waiting for some bits of register to change is a common
7113  *	operation for ATA controllers.  This function reads 32bit LE
7114  *	IO-mapped register @reg and tests for the following condition.
7115  *
7116  *	(*@reg & mask) != val
7117  *
7118  *	If the condition is met, it returns; otherwise, the process is
7119  *	repeated after @interval_msec until timeout.
7120  *
7121  *	LOCKING:
7122  *	Kernel thread context (may sleep)
7123  *
7124  *	RETURNS:
7125  *	The final register value.
7126  */
7127 u32 ata_wait_register(struct ata_port *ap, void __iomem *reg, u32 mask, u32 val,
7128 		      unsigned long interval, unsigned long timeout)
7129 {
7130 	unsigned long deadline;
7131 	u32 tmp;
7132 
7133 	tmp = ioread32(reg);
7134 
7135 	/* Calculate timeout _after_ the first read to make sure
7136 	 * preceding writes reach the controller before starting to
7137 	 * eat away the timeout.
7138 	 */
7139 	deadline = ata_deadline(jiffies, timeout);
7140 
7141 	while ((tmp & mask) == val && time_before(jiffies, deadline)) {
7142 		ata_msleep(ap, interval);
7143 		tmp = ioread32(reg);
7144 	}
7145 
7146 	return tmp;
7147 }
7148 
7149 /**
7150  *	sata_lpm_ignore_phy_events - test if PHY event should be ignored
7151  *	@link: Link receiving the event
7152  *
7153  *	Test whether the received PHY event has to be ignored or not.
7154  *
7155  *	LOCKING:
7156  *	None:
7157  *
7158  *	RETURNS:
7159  *	True if the event has to be ignored.
7160  */
7161 bool sata_lpm_ignore_phy_events(struct ata_link *link)
7162 {
7163 	unsigned long lpm_timeout = link->last_lpm_change +
7164 				    msecs_to_jiffies(ATA_TMOUT_SPURIOUS_PHY);
7165 
7166 	/* if LPM is enabled, PHYRDY doesn't mean anything */
7167 	if (link->lpm_policy > ATA_LPM_MAX_POWER)
7168 		return true;
7169 
7170 	/* ignore the first PHY event after the LPM policy changed
7171 	 * as it is might be spurious
7172 	 */
7173 	if ((link->flags & ATA_LFLAG_CHANGED) &&
7174 	    time_before(jiffies, lpm_timeout))
7175 		return true;
7176 
7177 	return false;
7178 }
7179 EXPORT_SYMBOL_GPL(sata_lpm_ignore_phy_events);
7180 
7181 /*
7182  * Dummy port_ops
7183  */
7184 static unsigned int ata_dummy_qc_issue(struct ata_queued_cmd *qc)
7185 {
7186 	return AC_ERR_SYSTEM;
7187 }
7188 
7189 static void ata_dummy_error_handler(struct ata_port *ap)
7190 {
7191 	/* truly dummy */
7192 }
7193 
7194 struct ata_port_operations ata_dummy_port_ops = {
7195 	.qc_prep		= ata_noop_qc_prep,
7196 	.qc_issue		= ata_dummy_qc_issue,
7197 	.error_handler		= ata_dummy_error_handler,
7198 	.sched_eh		= ata_std_sched_eh,
7199 	.end_eh			= ata_std_end_eh,
7200 };
7201 
7202 const struct ata_port_info ata_dummy_port_info = {
7203 	.port_ops		= &ata_dummy_port_ops,
7204 };
7205 
7206 /*
7207  * Utility print functions
7208  */
7209 void ata_port_printk(const struct ata_port *ap, const char *level,
7210 		     const char *fmt, ...)
7211 {
7212 	struct va_format vaf;
7213 	va_list args;
7214 
7215 	va_start(args, fmt);
7216 
7217 	vaf.fmt = fmt;
7218 	vaf.va = &args;
7219 
7220 	printk("%sata%u: %pV", level, ap->print_id, &vaf);
7221 
7222 	va_end(args);
7223 }
7224 EXPORT_SYMBOL(ata_port_printk);
7225 
7226 void ata_link_printk(const struct ata_link *link, const char *level,
7227 		     const char *fmt, ...)
7228 {
7229 	struct va_format vaf;
7230 	va_list args;
7231 
7232 	va_start(args, fmt);
7233 
7234 	vaf.fmt = fmt;
7235 	vaf.va = &args;
7236 
7237 	if (sata_pmp_attached(link->ap) || link->ap->slave_link)
7238 		printk("%sata%u.%02u: %pV",
7239 		       level, link->ap->print_id, link->pmp, &vaf);
7240 	else
7241 		printk("%sata%u: %pV",
7242 		       level, link->ap->print_id, &vaf);
7243 
7244 	va_end(args);
7245 }
7246 EXPORT_SYMBOL(ata_link_printk);
7247 
7248 void ata_dev_printk(const struct ata_device *dev, const char *level,
7249 		    const char *fmt, ...)
7250 {
7251 	struct va_format vaf;
7252 	va_list args;
7253 
7254 	va_start(args, fmt);
7255 
7256 	vaf.fmt = fmt;
7257 	vaf.va = &args;
7258 
7259 	printk("%sata%u.%02u: %pV",
7260 	       level, dev->link->ap->print_id, dev->link->pmp + dev->devno,
7261 	       &vaf);
7262 
7263 	va_end(args);
7264 }
7265 EXPORT_SYMBOL(ata_dev_printk);
7266 
7267 void ata_print_version(const struct device *dev, const char *version)
7268 {
7269 	dev_printk(KERN_DEBUG, dev, "version %s\n", version);
7270 }
7271 EXPORT_SYMBOL(ata_print_version);
7272 
7273 /*
7274  * libata is essentially a library of internal helper functions for
7275  * low-level ATA host controller drivers.  As such, the API/ABI is
7276  * likely to change as new drivers are added and updated.
7277  * Do not depend on ABI/API stability.
7278  */
7279 EXPORT_SYMBOL_GPL(sata_deb_timing_normal);
7280 EXPORT_SYMBOL_GPL(sata_deb_timing_hotplug);
7281 EXPORT_SYMBOL_GPL(sata_deb_timing_long);
7282 EXPORT_SYMBOL_GPL(ata_base_port_ops);
7283 EXPORT_SYMBOL_GPL(sata_port_ops);
7284 EXPORT_SYMBOL_GPL(ata_dummy_port_ops);
7285 EXPORT_SYMBOL_GPL(ata_dummy_port_info);
7286 EXPORT_SYMBOL_GPL(ata_link_next);
7287 EXPORT_SYMBOL_GPL(ata_dev_next);
7288 EXPORT_SYMBOL_GPL(ata_std_bios_param);
7289 EXPORT_SYMBOL_GPL(ata_scsi_unlock_native_capacity);
7290 EXPORT_SYMBOL_GPL(ata_host_init);
7291 EXPORT_SYMBOL_GPL(ata_host_alloc);
7292 EXPORT_SYMBOL_GPL(ata_host_alloc_pinfo);
7293 EXPORT_SYMBOL_GPL(ata_slave_link_init);
7294 EXPORT_SYMBOL_GPL(ata_host_start);
7295 EXPORT_SYMBOL_GPL(ata_host_register);
7296 EXPORT_SYMBOL_GPL(ata_host_activate);
7297 EXPORT_SYMBOL_GPL(ata_host_detach);
7298 EXPORT_SYMBOL_GPL(ata_sg_init);
7299 EXPORT_SYMBOL_GPL(ata_qc_complete);
7300 EXPORT_SYMBOL_GPL(ata_qc_complete_multiple);
7301 EXPORT_SYMBOL_GPL(atapi_cmd_type);
7302 EXPORT_SYMBOL_GPL(ata_tf_to_fis);
7303 EXPORT_SYMBOL_GPL(ata_tf_from_fis);
7304 EXPORT_SYMBOL_GPL(ata_pack_xfermask);
7305 EXPORT_SYMBOL_GPL(ata_unpack_xfermask);
7306 EXPORT_SYMBOL_GPL(ata_xfer_mask2mode);
7307 EXPORT_SYMBOL_GPL(ata_xfer_mode2mask);
7308 EXPORT_SYMBOL_GPL(ata_xfer_mode2shift);
7309 EXPORT_SYMBOL_GPL(ata_mode_string);
7310 EXPORT_SYMBOL_GPL(ata_id_xfermask);
7311 EXPORT_SYMBOL_GPL(ata_do_set_mode);
7312 EXPORT_SYMBOL_GPL(ata_std_qc_defer);
7313 EXPORT_SYMBOL_GPL(ata_noop_qc_prep);
7314 EXPORT_SYMBOL_GPL(ata_dev_disable);
7315 EXPORT_SYMBOL_GPL(sata_set_spd);
7316 EXPORT_SYMBOL_GPL(ata_wait_after_reset);
7317 EXPORT_SYMBOL_GPL(sata_link_debounce);
7318 EXPORT_SYMBOL_GPL(sata_link_resume);
7319 EXPORT_SYMBOL_GPL(sata_link_scr_lpm);
7320 EXPORT_SYMBOL_GPL(ata_std_prereset);
7321 EXPORT_SYMBOL_GPL(sata_link_hardreset);
7322 EXPORT_SYMBOL_GPL(sata_std_hardreset);
7323 EXPORT_SYMBOL_GPL(ata_std_postreset);
7324 EXPORT_SYMBOL_GPL(ata_dev_classify);
7325 EXPORT_SYMBOL_GPL(ata_dev_pair);
7326 EXPORT_SYMBOL_GPL(ata_ratelimit);
7327 EXPORT_SYMBOL_GPL(ata_msleep);
7328 EXPORT_SYMBOL_GPL(ata_wait_register);
7329 EXPORT_SYMBOL_GPL(ata_scsi_queuecmd);
7330 EXPORT_SYMBOL_GPL(ata_scsi_slave_config);
7331 EXPORT_SYMBOL_GPL(ata_scsi_slave_destroy);
7332 EXPORT_SYMBOL_GPL(ata_scsi_change_queue_depth);
7333 EXPORT_SYMBOL_GPL(__ata_change_queue_depth);
7334 EXPORT_SYMBOL_GPL(sata_scr_valid);
7335 EXPORT_SYMBOL_GPL(sata_scr_read);
7336 EXPORT_SYMBOL_GPL(sata_scr_write);
7337 EXPORT_SYMBOL_GPL(sata_scr_write_flush);
7338 EXPORT_SYMBOL_GPL(ata_link_online);
7339 EXPORT_SYMBOL_GPL(ata_link_offline);
7340 #ifdef CONFIG_PM
7341 EXPORT_SYMBOL_GPL(ata_host_suspend);
7342 EXPORT_SYMBOL_GPL(ata_host_resume);
7343 #endif /* CONFIG_PM */
7344 EXPORT_SYMBOL_GPL(ata_id_string);
7345 EXPORT_SYMBOL_GPL(ata_id_c_string);
7346 EXPORT_SYMBOL_GPL(ata_do_dev_read_id);
7347 EXPORT_SYMBOL_GPL(ata_scsi_simulate);
7348 
7349 EXPORT_SYMBOL_GPL(ata_pio_need_iordy);
7350 EXPORT_SYMBOL_GPL(ata_timing_find_mode);
7351 EXPORT_SYMBOL_GPL(ata_timing_compute);
7352 EXPORT_SYMBOL_GPL(ata_timing_merge);
7353 EXPORT_SYMBOL_GPL(ata_timing_cycle2mode);
7354 
7355 #ifdef CONFIG_PCI
7356 EXPORT_SYMBOL_GPL(pci_test_config_bits);
7357 EXPORT_SYMBOL_GPL(ata_pci_remove_one);
7358 #ifdef CONFIG_PM
7359 EXPORT_SYMBOL_GPL(ata_pci_device_do_suspend);
7360 EXPORT_SYMBOL_GPL(ata_pci_device_do_resume);
7361 EXPORT_SYMBOL_GPL(ata_pci_device_suspend);
7362 EXPORT_SYMBOL_GPL(ata_pci_device_resume);
7363 #endif /* CONFIG_PM */
7364 #endif /* CONFIG_PCI */
7365 
7366 EXPORT_SYMBOL_GPL(ata_platform_remove_one);
7367 
7368 EXPORT_SYMBOL_GPL(__ata_ehi_push_desc);
7369 EXPORT_SYMBOL_GPL(ata_ehi_push_desc);
7370 EXPORT_SYMBOL_GPL(ata_ehi_clear_desc);
7371 EXPORT_SYMBOL_GPL(ata_port_desc);
7372 #ifdef CONFIG_PCI
7373 EXPORT_SYMBOL_GPL(ata_port_pbar_desc);
7374 #endif /* CONFIG_PCI */
7375 EXPORT_SYMBOL_GPL(ata_port_schedule_eh);
7376 EXPORT_SYMBOL_GPL(ata_link_abort);
7377 EXPORT_SYMBOL_GPL(ata_port_abort);
7378 EXPORT_SYMBOL_GPL(ata_port_freeze);
7379 EXPORT_SYMBOL_GPL(sata_async_notification);
7380 EXPORT_SYMBOL_GPL(ata_eh_freeze_port);
7381 EXPORT_SYMBOL_GPL(ata_eh_thaw_port);
7382 EXPORT_SYMBOL_GPL(ata_eh_qc_complete);
7383 EXPORT_SYMBOL_GPL(ata_eh_qc_retry);
7384 EXPORT_SYMBOL_GPL(ata_eh_analyze_ncq_error);
7385 EXPORT_SYMBOL_GPL(ata_do_eh);
7386 EXPORT_SYMBOL_GPL(ata_std_error_handler);
7387 
7388 EXPORT_SYMBOL_GPL(ata_cable_40wire);
7389 EXPORT_SYMBOL_GPL(ata_cable_80wire);
7390 EXPORT_SYMBOL_GPL(ata_cable_unknown);
7391 EXPORT_SYMBOL_GPL(ata_cable_ignore);
7392 EXPORT_SYMBOL_GPL(ata_cable_sata);
7393 EXPORT_SYMBOL_GPL(ata_host_get);
7394 EXPORT_SYMBOL_GPL(ata_host_put);
7395