xref: /linux/drivers/ata/libata-core.c (revision d39d0ed196aa1685bb24771e92f78633c66ac9cb)
1 /*
2  *  libata-core.c - helper library for ATA
3  *
4  *  Maintained by:  Jeff Garzik <jgarzik@pobox.com>
5  *    		    Please ALWAYS copy linux-ide@vger.kernel.org
6  *		    on emails.
7  *
8  *  Copyright 2003-2004 Red Hat, Inc.  All rights reserved.
9  *  Copyright 2003-2004 Jeff Garzik
10  *
11  *
12  *  This program is free software; you can redistribute it and/or modify
13  *  it under the terms of the GNU General Public License as published by
14  *  the Free Software Foundation; either version 2, or (at your option)
15  *  any later version.
16  *
17  *  This program is distributed in the hope that it will be useful,
18  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
19  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  *  GNU General Public License for more details.
21  *
22  *  You should have received a copy of the GNU General Public License
23  *  along with this program; see the file COPYING.  If not, write to
24  *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
25  *
26  *
27  *  libata documentation is available via 'make {ps|pdf}docs',
28  *  as Documentation/DocBook/libata.*
29  *
30  *  Hardware documentation available from http://www.t13.org/ and
31  *  http://www.sata-io.org/
32  *
33  *  Standards documents from:
34  *	http://www.t13.org (ATA standards, PCI DMA IDE spec)
35  *	http://www.t10.org (SCSI MMC - for ATAPI MMC)
36  *	http://www.sata-io.org (SATA)
37  *	http://www.compactflash.org (CF)
38  *	http://www.qic.org (QIC157 - Tape and DSC)
39  *	http://www.ce-ata.org (CE-ATA: not supported)
40  *
41  */
42 
43 #include <linux/kernel.h>
44 #include <linux/module.h>
45 #include <linux/pci.h>
46 #include <linux/init.h>
47 #include <linux/list.h>
48 #include <linux/mm.h>
49 #include <linux/spinlock.h>
50 #include <linux/blkdev.h>
51 #include <linux/delay.h>
52 #include <linux/timer.h>
53 #include <linux/interrupt.h>
54 #include <linux/completion.h>
55 #include <linux/suspend.h>
56 #include <linux/workqueue.h>
57 #include <linux/scatterlist.h>
58 #include <linux/io.h>
59 #include <linux/async.h>
60 #include <linux/log2.h>
61 #include <linux/slab.h>
62 #include <scsi/scsi.h>
63 #include <scsi/scsi_cmnd.h>
64 #include <scsi/scsi_host.h>
65 #include <linux/libata.h>
66 #include <asm/byteorder.h>
67 #include <linux/cdrom.h>
68 #include <linux/ratelimit.h>
69 
70 #include "libata.h"
71 
72 
73 /* debounce timing parameters in msecs { interval, duration, timeout } */
74 const unsigned long sata_deb_timing_normal[]		= {   5,  100, 2000 };
75 const unsigned long sata_deb_timing_hotplug[]		= {  25,  500, 2000 };
76 const unsigned long sata_deb_timing_long[]		= { 100, 2000, 5000 };
77 
78 const struct ata_port_operations ata_base_port_ops = {
79 	.prereset		= ata_std_prereset,
80 	.postreset		= ata_std_postreset,
81 	.error_handler		= ata_std_error_handler,
82 };
83 
84 const struct ata_port_operations sata_port_ops = {
85 	.inherits		= &ata_base_port_ops,
86 
87 	.qc_defer		= ata_std_qc_defer,
88 	.hardreset		= sata_std_hardreset,
89 };
90 
91 static unsigned int ata_dev_init_params(struct ata_device *dev,
92 					u16 heads, u16 sectors);
93 static unsigned int ata_dev_set_xfermode(struct ata_device *dev);
94 static unsigned int ata_dev_set_feature(struct ata_device *dev,
95 					u8 enable, u8 feature);
96 static void ata_dev_xfermask(struct ata_device *dev);
97 static unsigned long ata_dev_blacklisted(const struct ata_device *dev);
98 
99 unsigned int ata_print_id = 1;
100 
101 struct ata_force_param {
102 	const char	*name;
103 	unsigned int	cbl;
104 	int		spd_limit;
105 	unsigned long	xfer_mask;
106 	unsigned int	horkage_on;
107 	unsigned int	horkage_off;
108 	unsigned int	lflags;
109 };
110 
111 struct ata_force_ent {
112 	int			port;
113 	int			device;
114 	struct ata_force_param	param;
115 };
116 
117 static struct ata_force_ent *ata_force_tbl;
118 static int ata_force_tbl_size;
119 
120 static char ata_force_param_buf[PAGE_SIZE] __initdata;
121 /* param_buf is thrown away after initialization, disallow read */
122 module_param_string(force, ata_force_param_buf, sizeof(ata_force_param_buf), 0);
123 MODULE_PARM_DESC(force, "Force ATA configurations including cable type, link speed and transfer mode (see Documentation/kernel-parameters.txt for details)");
124 
125 static int atapi_enabled = 1;
126 module_param(atapi_enabled, int, 0444);
127 MODULE_PARM_DESC(atapi_enabled, "Enable discovery of ATAPI devices (0=off, 1=on [default])");
128 
129 static int atapi_dmadir = 0;
130 module_param(atapi_dmadir, int, 0444);
131 MODULE_PARM_DESC(atapi_dmadir, "Enable ATAPI DMADIR bridge support (0=off [default], 1=on)");
132 
133 int atapi_passthru16 = 1;
134 module_param(atapi_passthru16, int, 0444);
135 MODULE_PARM_DESC(atapi_passthru16, "Enable ATA_16 passthru for ATAPI devices (0=off, 1=on [default])");
136 
137 int libata_fua = 0;
138 module_param_named(fua, libata_fua, int, 0444);
139 MODULE_PARM_DESC(fua, "FUA support (0=off [default], 1=on)");
140 
141 static int ata_ignore_hpa;
142 module_param_named(ignore_hpa, ata_ignore_hpa, int, 0644);
143 MODULE_PARM_DESC(ignore_hpa, "Ignore HPA limit (0=keep BIOS limits, 1=ignore limits, using full disk)");
144 
145 static int libata_dma_mask = ATA_DMA_MASK_ATA|ATA_DMA_MASK_ATAPI|ATA_DMA_MASK_CFA;
146 module_param_named(dma, libata_dma_mask, int, 0444);
147 MODULE_PARM_DESC(dma, "DMA enable/disable (0x1==ATA, 0x2==ATAPI, 0x4==CF)");
148 
149 static int ata_probe_timeout;
150 module_param(ata_probe_timeout, int, 0444);
151 MODULE_PARM_DESC(ata_probe_timeout, "Set ATA probing timeout (seconds)");
152 
153 int libata_noacpi = 0;
154 module_param_named(noacpi, libata_noacpi, int, 0444);
155 MODULE_PARM_DESC(noacpi, "Disable the use of ACPI in probe/suspend/resume (0=off [default], 1=on)");
156 
157 int libata_allow_tpm = 0;
158 module_param_named(allow_tpm, libata_allow_tpm, int, 0444);
159 MODULE_PARM_DESC(allow_tpm, "Permit the use of TPM commands (0=off [default], 1=on)");
160 
161 static int atapi_an;
162 module_param(atapi_an, int, 0444);
163 MODULE_PARM_DESC(atapi_an, "Enable ATAPI AN media presence notification (0=0ff [default], 1=on)");
164 
165 MODULE_AUTHOR("Jeff Garzik");
166 MODULE_DESCRIPTION("Library module for ATA devices");
167 MODULE_LICENSE("GPL");
168 MODULE_VERSION(DRV_VERSION);
169 
170 
171 static bool ata_sstatus_online(u32 sstatus)
172 {
173 	return (sstatus & 0xf) == 0x3;
174 }
175 
176 /**
177  *	ata_link_next - link iteration helper
178  *	@link: the previous link, NULL to start
179  *	@ap: ATA port containing links to iterate
180  *	@mode: iteration mode, one of ATA_LITER_*
181  *
182  *	LOCKING:
183  *	Host lock or EH context.
184  *
185  *	RETURNS:
186  *	Pointer to the next link.
187  */
188 struct ata_link *ata_link_next(struct ata_link *link, struct ata_port *ap,
189 			       enum ata_link_iter_mode mode)
190 {
191 	BUG_ON(mode != ATA_LITER_EDGE &&
192 	       mode != ATA_LITER_PMP_FIRST && mode != ATA_LITER_HOST_FIRST);
193 
194 	/* NULL link indicates start of iteration */
195 	if (!link)
196 		switch (mode) {
197 		case ATA_LITER_EDGE:
198 		case ATA_LITER_PMP_FIRST:
199 			if (sata_pmp_attached(ap))
200 				return ap->pmp_link;
201 			/* fall through */
202 		case ATA_LITER_HOST_FIRST:
203 			return &ap->link;
204 		}
205 
206 	/* we just iterated over the host link, what's next? */
207 	if (link == &ap->link)
208 		switch (mode) {
209 		case ATA_LITER_HOST_FIRST:
210 			if (sata_pmp_attached(ap))
211 				return ap->pmp_link;
212 			/* fall through */
213 		case ATA_LITER_PMP_FIRST:
214 			if (unlikely(ap->slave_link))
215 				return ap->slave_link;
216 			/* fall through */
217 		case ATA_LITER_EDGE:
218 			return NULL;
219 		}
220 
221 	/* slave_link excludes PMP */
222 	if (unlikely(link == ap->slave_link))
223 		return NULL;
224 
225 	/* we were over a PMP link */
226 	if (++link < ap->pmp_link + ap->nr_pmp_links)
227 		return link;
228 
229 	if (mode == ATA_LITER_PMP_FIRST)
230 		return &ap->link;
231 
232 	return NULL;
233 }
234 
235 /**
236  *	ata_dev_next - device iteration helper
237  *	@dev: the previous device, NULL to start
238  *	@link: ATA link containing devices to iterate
239  *	@mode: iteration mode, one of ATA_DITER_*
240  *
241  *	LOCKING:
242  *	Host lock or EH context.
243  *
244  *	RETURNS:
245  *	Pointer to the next device.
246  */
247 struct ata_device *ata_dev_next(struct ata_device *dev, struct ata_link *link,
248 				enum ata_dev_iter_mode mode)
249 {
250 	BUG_ON(mode != ATA_DITER_ENABLED && mode != ATA_DITER_ENABLED_REVERSE &&
251 	       mode != ATA_DITER_ALL && mode != ATA_DITER_ALL_REVERSE);
252 
253 	/* NULL dev indicates start of iteration */
254 	if (!dev)
255 		switch (mode) {
256 		case ATA_DITER_ENABLED:
257 		case ATA_DITER_ALL:
258 			dev = link->device;
259 			goto check;
260 		case ATA_DITER_ENABLED_REVERSE:
261 		case ATA_DITER_ALL_REVERSE:
262 			dev = link->device + ata_link_max_devices(link) - 1;
263 			goto check;
264 		}
265 
266  next:
267 	/* move to the next one */
268 	switch (mode) {
269 	case ATA_DITER_ENABLED:
270 	case ATA_DITER_ALL:
271 		if (++dev < link->device + ata_link_max_devices(link))
272 			goto check;
273 		return NULL;
274 	case ATA_DITER_ENABLED_REVERSE:
275 	case ATA_DITER_ALL_REVERSE:
276 		if (--dev >= link->device)
277 			goto check;
278 		return NULL;
279 	}
280 
281  check:
282 	if ((mode == ATA_DITER_ENABLED || mode == ATA_DITER_ENABLED_REVERSE) &&
283 	    !ata_dev_enabled(dev))
284 		goto next;
285 	return dev;
286 }
287 
288 /**
289  *	ata_dev_phys_link - find physical link for a device
290  *	@dev: ATA device to look up physical link for
291  *
292  *	Look up physical link which @dev is attached to.  Note that
293  *	this is different from @dev->link only when @dev is on slave
294  *	link.  For all other cases, it's the same as @dev->link.
295  *
296  *	LOCKING:
297  *	Don't care.
298  *
299  *	RETURNS:
300  *	Pointer to the found physical link.
301  */
302 struct ata_link *ata_dev_phys_link(struct ata_device *dev)
303 {
304 	struct ata_port *ap = dev->link->ap;
305 
306 	if (!ap->slave_link)
307 		return dev->link;
308 	if (!dev->devno)
309 		return &ap->link;
310 	return ap->slave_link;
311 }
312 
313 /**
314  *	ata_force_cbl - force cable type according to libata.force
315  *	@ap: ATA port of interest
316  *
317  *	Force cable type according to libata.force and whine about it.
318  *	The last entry which has matching port number is used, so it
319  *	can be specified as part of device force parameters.  For
320  *	example, both "a:40c,1.00:udma4" and "1.00:40c,udma4" have the
321  *	same effect.
322  *
323  *	LOCKING:
324  *	EH context.
325  */
326 void ata_force_cbl(struct ata_port *ap)
327 {
328 	int i;
329 
330 	for (i = ata_force_tbl_size - 1; i >= 0; i--) {
331 		const struct ata_force_ent *fe = &ata_force_tbl[i];
332 
333 		if (fe->port != -1 && fe->port != ap->print_id)
334 			continue;
335 
336 		if (fe->param.cbl == ATA_CBL_NONE)
337 			continue;
338 
339 		ap->cbl = fe->param.cbl;
340 		ata_port_printk(ap, KERN_NOTICE,
341 				"FORCE: cable set to %s\n", fe->param.name);
342 		return;
343 	}
344 }
345 
346 /**
347  *	ata_force_link_limits - force link limits according to libata.force
348  *	@link: ATA link of interest
349  *
350  *	Force link flags and SATA spd limit according to libata.force
351  *	and whine about it.  When only the port part is specified
352  *	(e.g. 1:), the limit applies to all links connected to both
353  *	the host link and all fan-out ports connected via PMP.  If the
354  *	device part is specified as 0 (e.g. 1.00:), it specifies the
355  *	first fan-out link not the host link.  Device number 15 always
356  *	points to the host link whether PMP is attached or not.  If the
357  *	controller has slave link, device number 16 points to it.
358  *
359  *	LOCKING:
360  *	EH context.
361  */
362 static void ata_force_link_limits(struct ata_link *link)
363 {
364 	bool did_spd = false;
365 	int linkno = link->pmp;
366 	int i;
367 
368 	if (ata_is_host_link(link))
369 		linkno += 15;
370 
371 	for (i = ata_force_tbl_size - 1; i >= 0; i--) {
372 		const struct ata_force_ent *fe = &ata_force_tbl[i];
373 
374 		if (fe->port != -1 && fe->port != link->ap->print_id)
375 			continue;
376 
377 		if (fe->device != -1 && fe->device != linkno)
378 			continue;
379 
380 		/* only honor the first spd limit */
381 		if (!did_spd && fe->param.spd_limit) {
382 			link->hw_sata_spd_limit = (1 << fe->param.spd_limit) - 1;
383 			ata_link_printk(link, KERN_NOTICE,
384 					"FORCE: PHY spd limit set to %s\n",
385 					fe->param.name);
386 			did_spd = true;
387 		}
388 
389 		/* let lflags stack */
390 		if (fe->param.lflags) {
391 			link->flags |= fe->param.lflags;
392 			ata_link_printk(link, KERN_NOTICE,
393 					"FORCE: link flag 0x%x forced -> 0x%x\n",
394 					fe->param.lflags, link->flags);
395 		}
396 	}
397 }
398 
399 /**
400  *	ata_force_xfermask - force xfermask according to libata.force
401  *	@dev: ATA device of interest
402  *
403  *	Force xfer_mask according to libata.force and whine about it.
404  *	For consistency with link selection, device number 15 selects
405  *	the first device connected to the host link.
406  *
407  *	LOCKING:
408  *	EH context.
409  */
410 static void ata_force_xfermask(struct ata_device *dev)
411 {
412 	int devno = dev->link->pmp + dev->devno;
413 	int alt_devno = devno;
414 	int i;
415 
416 	/* allow n.15/16 for devices attached to host port */
417 	if (ata_is_host_link(dev->link))
418 		alt_devno += 15;
419 
420 	for (i = ata_force_tbl_size - 1; i >= 0; i--) {
421 		const struct ata_force_ent *fe = &ata_force_tbl[i];
422 		unsigned long pio_mask, mwdma_mask, udma_mask;
423 
424 		if (fe->port != -1 && fe->port != dev->link->ap->print_id)
425 			continue;
426 
427 		if (fe->device != -1 && fe->device != devno &&
428 		    fe->device != alt_devno)
429 			continue;
430 
431 		if (!fe->param.xfer_mask)
432 			continue;
433 
434 		ata_unpack_xfermask(fe->param.xfer_mask,
435 				    &pio_mask, &mwdma_mask, &udma_mask);
436 		if (udma_mask)
437 			dev->udma_mask = udma_mask;
438 		else if (mwdma_mask) {
439 			dev->udma_mask = 0;
440 			dev->mwdma_mask = mwdma_mask;
441 		} else {
442 			dev->udma_mask = 0;
443 			dev->mwdma_mask = 0;
444 			dev->pio_mask = pio_mask;
445 		}
446 
447 		ata_dev_printk(dev, KERN_NOTICE,
448 			"FORCE: xfer_mask set to %s\n", fe->param.name);
449 		return;
450 	}
451 }
452 
453 /**
454  *	ata_force_horkage - force horkage according to libata.force
455  *	@dev: ATA device of interest
456  *
457  *	Force horkage according to libata.force and whine about it.
458  *	For consistency with link selection, device number 15 selects
459  *	the first device connected to the host link.
460  *
461  *	LOCKING:
462  *	EH context.
463  */
464 static void ata_force_horkage(struct ata_device *dev)
465 {
466 	int devno = dev->link->pmp + dev->devno;
467 	int alt_devno = devno;
468 	int i;
469 
470 	/* allow n.15/16 for devices attached to host port */
471 	if (ata_is_host_link(dev->link))
472 		alt_devno += 15;
473 
474 	for (i = 0; i < ata_force_tbl_size; i++) {
475 		const struct ata_force_ent *fe = &ata_force_tbl[i];
476 
477 		if (fe->port != -1 && fe->port != dev->link->ap->print_id)
478 			continue;
479 
480 		if (fe->device != -1 && fe->device != devno &&
481 		    fe->device != alt_devno)
482 			continue;
483 
484 		if (!(~dev->horkage & fe->param.horkage_on) &&
485 		    !(dev->horkage & fe->param.horkage_off))
486 			continue;
487 
488 		dev->horkage |= fe->param.horkage_on;
489 		dev->horkage &= ~fe->param.horkage_off;
490 
491 		ata_dev_printk(dev, KERN_NOTICE,
492 			"FORCE: horkage modified (%s)\n", fe->param.name);
493 	}
494 }
495 
496 /**
497  *	atapi_cmd_type - Determine ATAPI command type from SCSI opcode
498  *	@opcode: SCSI opcode
499  *
500  *	Determine ATAPI command type from @opcode.
501  *
502  *	LOCKING:
503  *	None.
504  *
505  *	RETURNS:
506  *	ATAPI_{READ|WRITE|READ_CD|PASS_THRU|MISC}
507  */
508 int atapi_cmd_type(u8 opcode)
509 {
510 	switch (opcode) {
511 	case GPCMD_READ_10:
512 	case GPCMD_READ_12:
513 		return ATAPI_READ;
514 
515 	case GPCMD_WRITE_10:
516 	case GPCMD_WRITE_12:
517 	case GPCMD_WRITE_AND_VERIFY_10:
518 		return ATAPI_WRITE;
519 
520 	case GPCMD_READ_CD:
521 	case GPCMD_READ_CD_MSF:
522 		return ATAPI_READ_CD;
523 
524 	case ATA_16:
525 	case ATA_12:
526 		if (atapi_passthru16)
527 			return ATAPI_PASS_THRU;
528 		/* fall thru */
529 	default:
530 		return ATAPI_MISC;
531 	}
532 }
533 
534 /**
535  *	ata_tf_to_fis - Convert ATA taskfile to SATA FIS structure
536  *	@tf: Taskfile to convert
537  *	@pmp: Port multiplier port
538  *	@is_cmd: This FIS is for command
539  *	@fis: Buffer into which data will output
540  *
541  *	Converts a standard ATA taskfile to a Serial ATA
542  *	FIS structure (Register - Host to Device).
543  *
544  *	LOCKING:
545  *	Inherited from caller.
546  */
547 void ata_tf_to_fis(const struct ata_taskfile *tf, u8 pmp, int is_cmd, u8 *fis)
548 {
549 	fis[0] = 0x27;			/* Register - Host to Device FIS */
550 	fis[1] = pmp & 0xf;		/* Port multiplier number*/
551 	if (is_cmd)
552 		fis[1] |= (1 << 7);	/* bit 7 indicates Command FIS */
553 
554 	fis[2] = tf->command;
555 	fis[3] = tf->feature;
556 
557 	fis[4] = tf->lbal;
558 	fis[5] = tf->lbam;
559 	fis[6] = tf->lbah;
560 	fis[7] = tf->device;
561 
562 	fis[8] = tf->hob_lbal;
563 	fis[9] = tf->hob_lbam;
564 	fis[10] = tf->hob_lbah;
565 	fis[11] = tf->hob_feature;
566 
567 	fis[12] = tf->nsect;
568 	fis[13] = tf->hob_nsect;
569 	fis[14] = 0;
570 	fis[15] = tf->ctl;
571 
572 	fis[16] = 0;
573 	fis[17] = 0;
574 	fis[18] = 0;
575 	fis[19] = 0;
576 }
577 
578 /**
579  *	ata_tf_from_fis - Convert SATA FIS to ATA taskfile
580  *	@fis: Buffer from which data will be input
581  *	@tf: Taskfile to output
582  *
583  *	Converts a serial ATA FIS structure to a standard ATA taskfile.
584  *
585  *	LOCKING:
586  *	Inherited from caller.
587  */
588 
589 void ata_tf_from_fis(const u8 *fis, struct ata_taskfile *tf)
590 {
591 	tf->command	= fis[2];	/* status */
592 	tf->feature	= fis[3];	/* error */
593 
594 	tf->lbal	= fis[4];
595 	tf->lbam	= fis[5];
596 	tf->lbah	= fis[6];
597 	tf->device	= fis[7];
598 
599 	tf->hob_lbal	= fis[8];
600 	tf->hob_lbam	= fis[9];
601 	tf->hob_lbah	= fis[10];
602 
603 	tf->nsect	= fis[12];
604 	tf->hob_nsect	= fis[13];
605 }
606 
607 static const u8 ata_rw_cmds[] = {
608 	/* pio multi */
609 	ATA_CMD_READ_MULTI,
610 	ATA_CMD_WRITE_MULTI,
611 	ATA_CMD_READ_MULTI_EXT,
612 	ATA_CMD_WRITE_MULTI_EXT,
613 	0,
614 	0,
615 	0,
616 	ATA_CMD_WRITE_MULTI_FUA_EXT,
617 	/* pio */
618 	ATA_CMD_PIO_READ,
619 	ATA_CMD_PIO_WRITE,
620 	ATA_CMD_PIO_READ_EXT,
621 	ATA_CMD_PIO_WRITE_EXT,
622 	0,
623 	0,
624 	0,
625 	0,
626 	/* dma */
627 	ATA_CMD_READ,
628 	ATA_CMD_WRITE,
629 	ATA_CMD_READ_EXT,
630 	ATA_CMD_WRITE_EXT,
631 	0,
632 	0,
633 	0,
634 	ATA_CMD_WRITE_FUA_EXT
635 };
636 
637 /**
638  *	ata_rwcmd_protocol - set taskfile r/w commands and protocol
639  *	@tf: command to examine and configure
640  *	@dev: device tf belongs to
641  *
642  *	Examine the device configuration and tf->flags to calculate
643  *	the proper read/write commands and protocol to use.
644  *
645  *	LOCKING:
646  *	caller.
647  */
648 static int ata_rwcmd_protocol(struct ata_taskfile *tf, struct ata_device *dev)
649 {
650 	u8 cmd;
651 
652 	int index, fua, lba48, write;
653 
654 	fua = (tf->flags & ATA_TFLAG_FUA) ? 4 : 0;
655 	lba48 = (tf->flags & ATA_TFLAG_LBA48) ? 2 : 0;
656 	write = (tf->flags & ATA_TFLAG_WRITE) ? 1 : 0;
657 
658 	if (dev->flags & ATA_DFLAG_PIO) {
659 		tf->protocol = ATA_PROT_PIO;
660 		index = dev->multi_count ? 0 : 8;
661 	} else if (lba48 && (dev->link->ap->flags & ATA_FLAG_PIO_LBA48)) {
662 		/* Unable to use DMA due to host limitation */
663 		tf->protocol = ATA_PROT_PIO;
664 		index = dev->multi_count ? 0 : 8;
665 	} else {
666 		tf->protocol = ATA_PROT_DMA;
667 		index = 16;
668 	}
669 
670 	cmd = ata_rw_cmds[index + fua + lba48 + write];
671 	if (cmd) {
672 		tf->command = cmd;
673 		return 0;
674 	}
675 	return -1;
676 }
677 
678 /**
679  *	ata_tf_read_block - Read block address from ATA taskfile
680  *	@tf: ATA taskfile of interest
681  *	@dev: ATA device @tf belongs to
682  *
683  *	LOCKING:
684  *	None.
685  *
686  *	Read block address from @tf.  This function can handle all
687  *	three address formats - LBA, LBA48 and CHS.  tf->protocol and
688  *	flags select the address format to use.
689  *
690  *	RETURNS:
691  *	Block address read from @tf.
692  */
693 u64 ata_tf_read_block(struct ata_taskfile *tf, struct ata_device *dev)
694 {
695 	u64 block = 0;
696 
697 	if (tf->flags & ATA_TFLAG_LBA) {
698 		if (tf->flags & ATA_TFLAG_LBA48) {
699 			block |= (u64)tf->hob_lbah << 40;
700 			block |= (u64)tf->hob_lbam << 32;
701 			block |= (u64)tf->hob_lbal << 24;
702 		} else
703 			block |= (tf->device & 0xf) << 24;
704 
705 		block |= tf->lbah << 16;
706 		block |= tf->lbam << 8;
707 		block |= tf->lbal;
708 	} else {
709 		u32 cyl, head, sect;
710 
711 		cyl = tf->lbam | (tf->lbah << 8);
712 		head = tf->device & 0xf;
713 		sect = tf->lbal;
714 
715 		if (!sect) {
716 			ata_dev_printk(dev, KERN_WARNING, "device reported "
717 				       "invalid CHS sector 0\n");
718 			sect = 1; /* oh well */
719 		}
720 
721 		block = (cyl * dev->heads + head) * dev->sectors + sect - 1;
722 	}
723 
724 	return block;
725 }
726 
727 /**
728  *	ata_build_rw_tf - Build ATA taskfile for given read/write request
729  *	@tf: Target ATA taskfile
730  *	@dev: ATA device @tf belongs to
731  *	@block: Block address
732  *	@n_block: Number of blocks
733  *	@tf_flags: RW/FUA etc...
734  *	@tag: tag
735  *
736  *	LOCKING:
737  *	None.
738  *
739  *	Build ATA taskfile @tf for read/write request described by
740  *	@block, @n_block, @tf_flags and @tag on @dev.
741  *
742  *	RETURNS:
743  *
744  *	0 on success, -ERANGE if the request is too large for @dev,
745  *	-EINVAL if the request is invalid.
746  */
747 int ata_build_rw_tf(struct ata_taskfile *tf, struct ata_device *dev,
748 		    u64 block, u32 n_block, unsigned int tf_flags,
749 		    unsigned int tag)
750 {
751 	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
752 	tf->flags |= tf_flags;
753 
754 	if (ata_ncq_enabled(dev) && likely(tag != ATA_TAG_INTERNAL)) {
755 		/* yay, NCQ */
756 		if (!lba_48_ok(block, n_block))
757 			return -ERANGE;
758 
759 		tf->protocol = ATA_PROT_NCQ;
760 		tf->flags |= ATA_TFLAG_LBA | ATA_TFLAG_LBA48;
761 
762 		if (tf->flags & ATA_TFLAG_WRITE)
763 			tf->command = ATA_CMD_FPDMA_WRITE;
764 		else
765 			tf->command = ATA_CMD_FPDMA_READ;
766 
767 		tf->nsect = tag << 3;
768 		tf->hob_feature = (n_block >> 8) & 0xff;
769 		tf->feature = n_block & 0xff;
770 
771 		tf->hob_lbah = (block >> 40) & 0xff;
772 		tf->hob_lbam = (block >> 32) & 0xff;
773 		tf->hob_lbal = (block >> 24) & 0xff;
774 		tf->lbah = (block >> 16) & 0xff;
775 		tf->lbam = (block >> 8) & 0xff;
776 		tf->lbal = block & 0xff;
777 
778 		tf->device = 1 << 6;
779 		if (tf->flags & ATA_TFLAG_FUA)
780 			tf->device |= 1 << 7;
781 	} else if (dev->flags & ATA_DFLAG_LBA) {
782 		tf->flags |= ATA_TFLAG_LBA;
783 
784 		if (lba_28_ok(block, n_block)) {
785 			/* use LBA28 */
786 			tf->device |= (block >> 24) & 0xf;
787 		} else if (lba_48_ok(block, n_block)) {
788 			if (!(dev->flags & ATA_DFLAG_LBA48))
789 				return -ERANGE;
790 
791 			/* use LBA48 */
792 			tf->flags |= ATA_TFLAG_LBA48;
793 
794 			tf->hob_nsect = (n_block >> 8) & 0xff;
795 
796 			tf->hob_lbah = (block >> 40) & 0xff;
797 			tf->hob_lbam = (block >> 32) & 0xff;
798 			tf->hob_lbal = (block >> 24) & 0xff;
799 		} else
800 			/* request too large even for LBA48 */
801 			return -ERANGE;
802 
803 		if (unlikely(ata_rwcmd_protocol(tf, dev) < 0))
804 			return -EINVAL;
805 
806 		tf->nsect = n_block & 0xff;
807 
808 		tf->lbah = (block >> 16) & 0xff;
809 		tf->lbam = (block >> 8) & 0xff;
810 		tf->lbal = block & 0xff;
811 
812 		tf->device |= ATA_LBA;
813 	} else {
814 		/* CHS */
815 		u32 sect, head, cyl, track;
816 
817 		/* The request -may- be too large for CHS addressing. */
818 		if (!lba_28_ok(block, n_block))
819 			return -ERANGE;
820 
821 		if (unlikely(ata_rwcmd_protocol(tf, dev) < 0))
822 			return -EINVAL;
823 
824 		/* Convert LBA to CHS */
825 		track = (u32)block / dev->sectors;
826 		cyl   = track / dev->heads;
827 		head  = track % dev->heads;
828 		sect  = (u32)block % dev->sectors + 1;
829 
830 		DPRINTK("block %u track %u cyl %u head %u sect %u\n",
831 			(u32)block, track, cyl, head, sect);
832 
833 		/* Check whether the converted CHS can fit.
834 		   Cylinder: 0-65535
835 		   Head: 0-15
836 		   Sector: 1-255*/
837 		if ((cyl >> 16) || (head >> 4) || (sect >> 8) || (!sect))
838 			return -ERANGE;
839 
840 		tf->nsect = n_block & 0xff; /* Sector count 0 means 256 sectors */
841 		tf->lbal = sect;
842 		tf->lbam = cyl;
843 		tf->lbah = cyl >> 8;
844 		tf->device |= head;
845 	}
846 
847 	return 0;
848 }
849 
850 /**
851  *	ata_pack_xfermask - Pack pio, mwdma and udma masks into xfer_mask
852  *	@pio_mask: pio_mask
853  *	@mwdma_mask: mwdma_mask
854  *	@udma_mask: udma_mask
855  *
856  *	Pack @pio_mask, @mwdma_mask and @udma_mask into a single
857  *	unsigned int xfer_mask.
858  *
859  *	LOCKING:
860  *	None.
861  *
862  *	RETURNS:
863  *	Packed xfer_mask.
864  */
865 unsigned long ata_pack_xfermask(unsigned long pio_mask,
866 				unsigned long mwdma_mask,
867 				unsigned long udma_mask)
868 {
869 	return ((pio_mask << ATA_SHIFT_PIO) & ATA_MASK_PIO) |
870 		((mwdma_mask << ATA_SHIFT_MWDMA) & ATA_MASK_MWDMA) |
871 		((udma_mask << ATA_SHIFT_UDMA) & ATA_MASK_UDMA);
872 }
873 
874 /**
875  *	ata_unpack_xfermask - Unpack xfer_mask into pio, mwdma and udma masks
876  *	@xfer_mask: xfer_mask to unpack
877  *	@pio_mask: resulting pio_mask
878  *	@mwdma_mask: resulting mwdma_mask
879  *	@udma_mask: resulting udma_mask
880  *
881  *	Unpack @xfer_mask into @pio_mask, @mwdma_mask and @udma_mask.
882  *	Any NULL distination masks will be ignored.
883  */
884 void ata_unpack_xfermask(unsigned long xfer_mask, unsigned long *pio_mask,
885 			 unsigned long *mwdma_mask, unsigned long *udma_mask)
886 {
887 	if (pio_mask)
888 		*pio_mask = (xfer_mask & ATA_MASK_PIO) >> ATA_SHIFT_PIO;
889 	if (mwdma_mask)
890 		*mwdma_mask = (xfer_mask & ATA_MASK_MWDMA) >> ATA_SHIFT_MWDMA;
891 	if (udma_mask)
892 		*udma_mask = (xfer_mask & ATA_MASK_UDMA) >> ATA_SHIFT_UDMA;
893 }
894 
895 static const struct ata_xfer_ent {
896 	int shift, bits;
897 	u8 base;
898 } ata_xfer_tbl[] = {
899 	{ ATA_SHIFT_PIO, ATA_NR_PIO_MODES, XFER_PIO_0 },
900 	{ ATA_SHIFT_MWDMA, ATA_NR_MWDMA_MODES, XFER_MW_DMA_0 },
901 	{ ATA_SHIFT_UDMA, ATA_NR_UDMA_MODES, XFER_UDMA_0 },
902 	{ -1, },
903 };
904 
905 /**
906  *	ata_xfer_mask2mode - Find matching XFER_* for the given xfer_mask
907  *	@xfer_mask: xfer_mask of interest
908  *
909  *	Return matching XFER_* value for @xfer_mask.  Only the highest
910  *	bit of @xfer_mask is considered.
911  *
912  *	LOCKING:
913  *	None.
914  *
915  *	RETURNS:
916  *	Matching XFER_* value, 0xff if no match found.
917  */
918 u8 ata_xfer_mask2mode(unsigned long xfer_mask)
919 {
920 	int highbit = fls(xfer_mask) - 1;
921 	const struct ata_xfer_ent *ent;
922 
923 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
924 		if (highbit >= ent->shift && highbit < ent->shift + ent->bits)
925 			return ent->base + highbit - ent->shift;
926 	return 0xff;
927 }
928 
929 /**
930  *	ata_xfer_mode2mask - Find matching xfer_mask for XFER_*
931  *	@xfer_mode: XFER_* of interest
932  *
933  *	Return matching xfer_mask for @xfer_mode.
934  *
935  *	LOCKING:
936  *	None.
937  *
938  *	RETURNS:
939  *	Matching xfer_mask, 0 if no match found.
940  */
941 unsigned long ata_xfer_mode2mask(u8 xfer_mode)
942 {
943 	const struct ata_xfer_ent *ent;
944 
945 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
946 		if (xfer_mode >= ent->base && xfer_mode < ent->base + ent->bits)
947 			return ((2 << (ent->shift + xfer_mode - ent->base)) - 1)
948 				& ~((1 << ent->shift) - 1);
949 	return 0;
950 }
951 
952 /**
953  *	ata_xfer_mode2shift - Find matching xfer_shift for XFER_*
954  *	@xfer_mode: XFER_* of interest
955  *
956  *	Return matching xfer_shift for @xfer_mode.
957  *
958  *	LOCKING:
959  *	None.
960  *
961  *	RETURNS:
962  *	Matching xfer_shift, -1 if no match found.
963  */
964 int ata_xfer_mode2shift(unsigned long xfer_mode)
965 {
966 	const struct ata_xfer_ent *ent;
967 
968 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
969 		if (xfer_mode >= ent->base && xfer_mode < ent->base + ent->bits)
970 			return ent->shift;
971 	return -1;
972 }
973 
974 /**
975  *	ata_mode_string - convert xfer_mask to string
976  *	@xfer_mask: mask of bits supported; only highest bit counts.
977  *
978  *	Determine string which represents the highest speed
979  *	(highest bit in @modemask).
980  *
981  *	LOCKING:
982  *	None.
983  *
984  *	RETURNS:
985  *	Constant C string representing highest speed listed in
986  *	@mode_mask, or the constant C string "<n/a>".
987  */
988 const char *ata_mode_string(unsigned long xfer_mask)
989 {
990 	static const char * const xfer_mode_str[] = {
991 		"PIO0",
992 		"PIO1",
993 		"PIO2",
994 		"PIO3",
995 		"PIO4",
996 		"PIO5",
997 		"PIO6",
998 		"MWDMA0",
999 		"MWDMA1",
1000 		"MWDMA2",
1001 		"MWDMA3",
1002 		"MWDMA4",
1003 		"UDMA/16",
1004 		"UDMA/25",
1005 		"UDMA/33",
1006 		"UDMA/44",
1007 		"UDMA/66",
1008 		"UDMA/100",
1009 		"UDMA/133",
1010 		"UDMA7",
1011 	};
1012 	int highbit;
1013 
1014 	highbit = fls(xfer_mask) - 1;
1015 	if (highbit >= 0 && highbit < ARRAY_SIZE(xfer_mode_str))
1016 		return xfer_mode_str[highbit];
1017 	return "<n/a>";
1018 }
1019 
1020 static const char *sata_spd_string(unsigned int spd)
1021 {
1022 	static const char * const spd_str[] = {
1023 		"1.5 Gbps",
1024 		"3.0 Gbps",
1025 		"6.0 Gbps",
1026 	};
1027 
1028 	if (spd == 0 || (spd - 1) >= ARRAY_SIZE(spd_str))
1029 		return "<unknown>";
1030 	return spd_str[spd - 1];
1031 }
1032 
1033 static int ata_dev_set_dipm(struct ata_device *dev, enum link_pm policy)
1034 {
1035 	struct ata_link *link = dev->link;
1036 	struct ata_port *ap = link->ap;
1037 	u32 scontrol;
1038 	unsigned int err_mask;
1039 	int rc;
1040 
1041 	/*
1042 	 * disallow DIPM for drivers which haven't set
1043 	 * ATA_FLAG_IPM.  This is because when DIPM is enabled,
1044 	 * phy ready will be set in the interrupt status on
1045 	 * state changes, which will cause some drivers to
1046 	 * think there are errors - additionally drivers will
1047 	 * need to disable hot plug.
1048 	 */
1049 	if (!(ap->flags & ATA_FLAG_IPM) || !ata_dev_enabled(dev)) {
1050 		ap->pm_policy = NOT_AVAILABLE;
1051 		return -EINVAL;
1052 	}
1053 
1054 	/*
1055 	 * For DIPM, we will only enable it for the
1056 	 * min_power setting.
1057 	 *
1058 	 * Why?  Because Disks are too stupid to know that
1059 	 * If the host rejects a request to go to SLUMBER
1060 	 * they should retry at PARTIAL, and instead it
1061 	 * just would give up.  So, for medium_power to
1062 	 * work at all, we need to only allow HIPM.
1063 	 */
1064 	rc = sata_scr_read(link, SCR_CONTROL, &scontrol);
1065 	if (rc)
1066 		return rc;
1067 
1068 	switch (policy) {
1069 	case MIN_POWER:
1070 		/* no restrictions on IPM transitions */
1071 		scontrol &= ~(0x3 << 8);
1072 		rc = sata_scr_write(link, SCR_CONTROL, scontrol);
1073 		if (rc)
1074 			return rc;
1075 
1076 		/* enable DIPM */
1077 		if (dev->flags & ATA_DFLAG_DIPM)
1078 			err_mask = ata_dev_set_feature(dev,
1079 					SETFEATURES_SATA_ENABLE, SATA_DIPM);
1080 		break;
1081 	case MEDIUM_POWER:
1082 		/* allow IPM to PARTIAL */
1083 		scontrol &= ~(0x1 << 8);
1084 		scontrol |= (0x2 << 8);
1085 		rc = sata_scr_write(link, SCR_CONTROL, scontrol);
1086 		if (rc)
1087 			return rc;
1088 
1089 		/*
1090 		 * we don't have to disable DIPM since IPM flags
1091 		 * disallow transitions to SLUMBER, which effectively
1092 		 * disable DIPM if it does not support PARTIAL
1093 		 */
1094 		break;
1095 	case NOT_AVAILABLE:
1096 	case MAX_PERFORMANCE:
1097 		/* disable all IPM transitions */
1098 		scontrol |= (0x3 << 8);
1099 		rc = sata_scr_write(link, SCR_CONTROL, scontrol);
1100 		if (rc)
1101 			return rc;
1102 
1103 		/*
1104 		 * we don't have to disable DIPM since IPM flags
1105 		 * disallow all transitions which effectively
1106 		 * disable DIPM anyway.
1107 		 */
1108 		break;
1109 	}
1110 
1111 	/* FIXME: handle SET FEATURES failure */
1112 	(void) err_mask;
1113 
1114 	return 0;
1115 }
1116 
1117 /**
1118  *	ata_dev_enable_pm - enable SATA interface power management
1119  *	@dev:  device to enable power management
1120  *	@policy: the link power management policy
1121  *
1122  *	Enable SATA Interface power management.  This will enable
1123  *	Device Interface Power Management (DIPM) for min_power
1124  * 	policy, and then call driver specific callbacks for
1125  *	enabling Host Initiated Power management.
1126  *
1127  *	Locking: Caller.
1128  *	Returns: -EINVAL if IPM is not supported, 0 otherwise.
1129  */
1130 void ata_dev_enable_pm(struct ata_device *dev, enum link_pm policy)
1131 {
1132 	int rc = 0;
1133 	struct ata_port *ap = dev->link->ap;
1134 
1135 	/* set HIPM first, then DIPM */
1136 	if (ap->ops->enable_pm)
1137 		rc = ap->ops->enable_pm(ap, policy);
1138 	if (rc)
1139 		goto enable_pm_out;
1140 	rc = ata_dev_set_dipm(dev, policy);
1141 
1142 enable_pm_out:
1143 	if (rc)
1144 		ap->pm_policy = MAX_PERFORMANCE;
1145 	else
1146 		ap->pm_policy = policy;
1147 	return /* rc */;	/* hopefully we can use 'rc' eventually */
1148 }
1149 
1150 #ifdef CONFIG_PM
1151 /**
1152  *	ata_dev_disable_pm - disable SATA interface power management
1153  *	@dev: device to disable power management
1154  *
1155  *	Disable SATA Interface power management.  This will disable
1156  *	Device Interface Power Management (DIPM) without changing
1157  * 	policy,  call driver specific callbacks for disabling Host
1158  * 	Initiated Power management.
1159  *
1160  *	Locking: Caller.
1161  *	Returns: void
1162  */
1163 static void ata_dev_disable_pm(struct ata_device *dev)
1164 {
1165 	struct ata_port *ap = dev->link->ap;
1166 
1167 	ata_dev_set_dipm(dev, MAX_PERFORMANCE);
1168 	if (ap->ops->disable_pm)
1169 		ap->ops->disable_pm(ap);
1170 }
1171 #endif	/* CONFIG_PM */
1172 
1173 void ata_lpm_schedule(struct ata_port *ap, enum link_pm policy)
1174 {
1175 	ap->pm_policy = policy;
1176 	ap->link.eh_info.action |= ATA_EH_LPM;
1177 	ap->link.eh_info.flags |= ATA_EHI_NO_AUTOPSY;
1178 	ata_port_schedule_eh(ap);
1179 }
1180 
1181 #ifdef CONFIG_PM
1182 static void ata_lpm_enable(struct ata_host *host)
1183 {
1184 	struct ata_link *link;
1185 	struct ata_port *ap;
1186 	struct ata_device *dev;
1187 	int i;
1188 
1189 	for (i = 0; i < host->n_ports; i++) {
1190 		ap = host->ports[i];
1191 		ata_for_each_link(link, ap, EDGE) {
1192 			ata_for_each_dev(dev, link, ALL)
1193 				ata_dev_disable_pm(dev);
1194 		}
1195 	}
1196 }
1197 
1198 static void ata_lpm_disable(struct ata_host *host)
1199 {
1200 	int i;
1201 
1202 	for (i = 0; i < host->n_ports; i++) {
1203 		struct ata_port *ap = host->ports[i];
1204 		ata_lpm_schedule(ap, ap->pm_policy);
1205 	}
1206 }
1207 #endif	/* CONFIG_PM */
1208 
1209 /**
1210  *	ata_dev_classify - determine device type based on ATA-spec signature
1211  *	@tf: ATA taskfile register set for device to be identified
1212  *
1213  *	Determine from taskfile register contents whether a device is
1214  *	ATA or ATAPI, as per "Signature and persistence" section
1215  *	of ATA/PI spec (volume 1, sect 5.14).
1216  *
1217  *	LOCKING:
1218  *	None.
1219  *
1220  *	RETURNS:
1221  *	Device type, %ATA_DEV_ATA, %ATA_DEV_ATAPI, %ATA_DEV_PMP or
1222  *	%ATA_DEV_UNKNOWN the event of failure.
1223  */
1224 unsigned int ata_dev_classify(const struct ata_taskfile *tf)
1225 {
1226 	/* Apple's open source Darwin code hints that some devices only
1227 	 * put a proper signature into the LBA mid/high registers,
1228 	 * So, we only check those.  It's sufficient for uniqueness.
1229 	 *
1230 	 * ATA/ATAPI-7 (d1532v1r1: Feb. 19, 2003) specified separate
1231 	 * signatures for ATA and ATAPI devices attached on SerialATA,
1232 	 * 0x3c/0xc3 and 0x69/0x96 respectively.  However, SerialATA
1233 	 * spec has never mentioned about using different signatures
1234 	 * for ATA/ATAPI devices.  Then, Serial ATA II: Port
1235 	 * Multiplier specification began to use 0x69/0x96 to identify
1236 	 * port multpliers and 0x3c/0xc3 to identify SEMB device.
1237 	 * ATA/ATAPI-7 dropped descriptions about 0x3c/0xc3 and
1238 	 * 0x69/0x96 shortly and described them as reserved for
1239 	 * SerialATA.
1240 	 *
1241 	 * We follow the current spec and consider that 0x69/0x96
1242 	 * identifies a port multiplier and 0x3c/0xc3 a SEMB device.
1243 	 * Unfortunately, WDC WD1600JS-62MHB5 (a hard drive) reports
1244 	 * SEMB signature.  This is worked around in
1245 	 * ata_dev_read_id().
1246 	 */
1247 	if ((tf->lbam == 0) && (tf->lbah == 0)) {
1248 		DPRINTK("found ATA device by sig\n");
1249 		return ATA_DEV_ATA;
1250 	}
1251 
1252 	if ((tf->lbam == 0x14) && (tf->lbah == 0xeb)) {
1253 		DPRINTK("found ATAPI device by sig\n");
1254 		return ATA_DEV_ATAPI;
1255 	}
1256 
1257 	if ((tf->lbam == 0x69) && (tf->lbah == 0x96)) {
1258 		DPRINTK("found PMP device by sig\n");
1259 		return ATA_DEV_PMP;
1260 	}
1261 
1262 	if ((tf->lbam == 0x3c) && (tf->lbah == 0xc3)) {
1263 		DPRINTK("found SEMB device by sig (could be ATA device)\n");
1264 		return ATA_DEV_SEMB;
1265 	}
1266 
1267 	DPRINTK("unknown device\n");
1268 	return ATA_DEV_UNKNOWN;
1269 }
1270 
1271 /**
1272  *	ata_id_string - Convert IDENTIFY DEVICE page into string
1273  *	@id: IDENTIFY DEVICE results we will examine
1274  *	@s: string into which data is output
1275  *	@ofs: offset into identify device page
1276  *	@len: length of string to return. must be an even number.
1277  *
1278  *	The strings in the IDENTIFY DEVICE page are broken up into
1279  *	16-bit chunks.  Run through the string, and output each
1280  *	8-bit chunk linearly, regardless of platform.
1281  *
1282  *	LOCKING:
1283  *	caller.
1284  */
1285 
1286 void ata_id_string(const u16 *id, unsigned char *s,
1287 		   unsigned int ofs, unsigned int len)
1288 {
1289 	unsigned int c;
1290 
1291 	BUG_ON(len & 1);
1292 
1293 	while (len > 0) {
1294 		c = id[ofs] >> 8;
1295 		*s = c;
1296 		s++;
1297 
1298 		c = id[ofs] & 0xff;
1299 		*s = c;
1300 		s++;
1301 
1302 		ofs++;
1303 		len -= 2;
1304 	}
1305 }
1306 
1307 /**
1308  *	ata_id_c_string - Convert IDENTIFY DEVICE page into C string
1309  *	@id: IDENTIFY DEVICE results we will examine
1310  *	@s: string into which data is output
1311  *	@ofs: offset into identify device page
1312  *	@len: length of string to return. must be an odd number.
1313  *
1314  *	This function is identical to ata_id_string except that it
1315  *	trims trailing spaces and terminates the resulting string with
1316  *	null.  @len must be actual maximum length (even number) + 1.
1317  *
1318  *	LOCKING:
1319  *	caller.
1320  */
1321 void ata_id_c_string(const u16 *id, unsigned char *s,
1322 		     unsigned int ofs, unsigned int len)
1323 {
1324 	unsigned char *p;
1325 
1326 	ata_id_string(id, s, ofs, len - 1);
1327 
1328 	p = s + strnlen(s, len - 1);
1329 	while (p > s && p[-1] == ' ')
1330 		p--;
1331 	*p = '\0';
1332 }
1333 
1334 static u64 ata_id_n_sectors(const u16 *id)
1335 {
1336 	if (ata_id_has_lba(id)) {
1337 		if (ata_id_has_lba48(id))
1338 			return ata_id_u64(id, ATA_ID_LBA_CAPACITY_2);
1339 		else
1340 			return ata_id_u32(id, ATA_ID_LBA_CAPACITY);
1341 	} else {
1342 		if (ata_id_current_chs_valid(id))
1343 			return id[ATA_ID_CUR_CYLS] * id[ATA_ID_CUR_HEADS] *
1344 			       id[ATA_ID_CUR_SECTORS];
1345 		else
1346 			return id[ATA_ID_CYLS] * id[ATA_ID_HEADS] *
1347 			       id[ATA_ID_SECTORS];
1348 	}
1349 }
1350 
1351 u64 ata_tf_to_lba48(const struct ata_taskfile *tf)
1352 {
1353 	u64 sectors = 0;
1354 
1355 	sectors |= ((u64)(tf->hob_lbah & 0xff)) << 40;
1356 	sectors |= ((u64)(tf->hob_lbam & 0xff)) << 32;
1357 	sectors |= ((u64)(tf->hob_lbal & 0xff)) << 24;
1358 	sectors |= (tf->lbah & 0xff) << 16;
1359 	sectors |= (tf->lbam & 0xff) << 8;
1360 	sectors |= (tf->lbal & 0xff);
1361 
1362 	return sectors;
1363 }
1364 
1365 u64 ata_tf_to_lba(const struct ata_taskfile *tf)
1366 {
1367 	u64 sectors = 0;
1368 
1369 	sectors |= (tf->device & 0x0f) << 24;
1370 	sectors |= (tf->lbah & 0xff) << 16;
1371 	sectors |= (tf->lbam & 0xff) << 8;
1372 	sectors |= (tf->lbal & 0xff);
1373 
1374 	return sectors;
1375 }
1376 
1377 /**
1378  *	ata_read_native_max_address - Read native max address
1379  *	@dev: target device
1380  *	@max_sectors: out parameter for the result native max address
1381  *
1382  *	Perform an LBA48 or LBA28 native size query upon the device in
1383  *	question.
1384  *
1385  *	RETURNS:
1386  *	0 on success, -EACCES if command is aborted by the drive.
1387  *	-EIO on other errors.
1388  */
1389 static int ata_read_native_max_address(struct ata_device *dev, u64 *max_sectors)
1390 {
1391 	unsigned int err_mask;
1392 	struct ata_taskfile tf;
1393 	int lba48 = ata_id_has_lba48(dev->id);
1394 
1395 	ata_tf_init(dev, &tf);
1396 
1397 	/* always clear all address registers */
1398 	tf.flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
1399 
1400 	if (lba48) {
1401 		tf.command = ATA_CMD_READ_NATIVE_MAX_EXT;
1402 		tf.flags |= ATA_TFLAG_LBA48;
1403 	} else
1404 		tf.command = ATA_CMD_READ_NATIVE_MAX;
1405 
1406 	tf.protocol |= ATA_PROT_NODATA;
1407 	tf.device |= ATA_LBA;
1408 
1409 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
1410 	if (err_mask) {
1411 		ata_dev_printk(dev, KERN_WARNING, "failed to read native "
1412 			       "max address (err_mask=0x%x)\n", err_mask);
1413 		if (err_mask == AC_ERR_DEV && (tf.feature & ATA_ABORTED))
1414 			return -EACCES;
1415 		return -EIO;
1416 	}
1417 
1418 	if (lba48)
1419 		*max_sectors = ata_tf_to_lba48(&tf) + 1;
1420 	else
1421 		*max_sectors = ata_tf_to_lba(&tf) + 1;
1422 	if (dev->horkage & ATA_HORKAGE_HPA_SIZE)
1423 		(*max_sectors)--;
1424 	return 0;
1425 }
1426 
1427 /**
1428  *	ata_set_max_sectors - Set max sectors
1429  *	@dev: target device
1430  *	@new_sectors: new max sectors value to set for the device
1431  *
1432  *	Set max sectors of @dev to @new_sectors.
1433  *
1434  *	RETURNS:
1435  *	0 on success, -EACCES if command is aborted or denied (due to
1436  *	previous non-volatile SET_MAX) by the drive.  -EIO on other
1437  *	errors.
1438  */
1439 static int ata_set_max_sectors(struct ata_device *dev, u64 new_sectors)
1440 {
1441 	unsigned int err_mask;
1442 	struct ata_taskfile tf;
1443 	int lba48 = ata_id_has_lba48(dev->id);
1444 
1445 	new_sectors--;
1446 
1447 	ata_tf_init(dev, &tf);
1448 
1449 	tf.flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
1450 
1451 	if (lba48) {
1452 		tf.command = ATA_CMD_SET_MAX_EXT;
1453 		tf.flags |= ATA_TFLAG_LBA48;
1454 
1455 		tf.hob_lbal = (new_sectors >> 24) & 0xff;
1456 		tf.hob_lbam = (new_sectors >> 32) & 0xff;
1457 		tf.hob_lbah = (new_sectors >> 40) & 0xff;
1458 	} else {
1459 		tf.command = ATA_CMD_SET_MAX;
1460 
1461 		tf.device |= (new_sectors >> 24) & 0xf;
1462 	}
1463 
1464 	tf.protocol |= ATA_PROT_NODATA;
1465 	tf.device |= ATA_LBA;
1466 
1467 	tf.lbal = (new_sectors >> 0) & 0xff;
1468 	tf.lbam = (new_sectors >> 8) & 0xff;
1469 	tf.lbah = (new_sectors >> 16) & 0xff;
1470 
1471 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
1472 	if (err_mask) {
1473 		ata_dev_printk(dev, KERN_WARNING, "failed to set "
1474 			       "max address (err_mask=0x%x)\n", err_mask);
1475 		if (err_mask == AC_ERR_DEV &&
1476 		    (tf.feature & (ATA_ABORTED | ATA_IDNF)))
1477 			return -EACCES;
1478 		return -EIO;
1479 	}
1480 
1481 	return 0;
1482 }
1483 
1484 /**
1485  *	ata_hpa_resize		-	Resize a device with an HPA set
1486  *	@dev: Device to resize
1487  *
1488  *	Read the size of an LBA28 or LBA48 disk with HPA features and resize
1489  *	it if required to the full size of the media. The caller must check
1490  *	the drive has the HPA feature set enabled.
1491  *
1492  *	RETURNS:
1493  *	0 on success, -errno on failure.
1494  */
1495 static int ata_hpa_resize(struct ata_device *dev)
1496 {
1497 	struct ata_eh_context *ehc = &dev->link->eh_context;
1498 	int print_info = ehc->i.flags & ATA_EHI_PRINTINFO;
1499 	bool unlock_hpa = ata_ignore_hpa || dev->flags & ATA_DFLAG_UNLOCK_HPA;
1500 	u64 sectors = ata_id_n_sectors(dev->id);
1501 	u64 native_sectors;
1502 	int rc;
1503 
1504 	/* do we need to do it? */
1505 	if (dev->class != ATA_DEV_ATA ||
1506 	    !ata_id_has_lba(dev->id) || !ata_id_hpa_enabled(dev->id) ||
1507 	    (dev->horkage & ATA_HORKAGE_BROKEN_HPA))
1508 		return 0;
1509 
1510 	/* read native max address */
1511 	rc = ata_read_native_max_address(dev, &native_sectors);
1512 	if (rc) {
1513 		/* If device aborted the command or HPA isn't going to
1514 		 * be unlocked, skip HPA resizing.
1515 		 */
1516 		if (rc == -EACCES || !unlock_hpa) {
1517 			ata_dev_printk(dev, KERN_WARNING, "HPA support seems "
1518 				       "broken, skipping HPA handling\n");
1519 			dev->horkage |= ATA_HORKAGE_BROKEN_HPA;
1520 
1521 			/* we can continue if device aborted the command */
1522 			if (rc == -EACCES)
1523 				rc = 0;
1524 		}
1525 
1526 		return rc;
1527 	}
1528 	dev->n_native_sectors = native_sectors;
1529 
1530 	/* nothing to do? */
1531 	if (native_sectors <= sectors || !unlock_hpa) {
1532 		if (!print_info || native_sectors == sectors)
1533 			return 0;
1534 
1535 		if (native_sectors > sectors)
1536 			ata_dev_printk(dev, KERN_INFO,
1537 				"HPA detected: current %llu, native %llu\n",
1538 				(unsigned long long)sectors,
1539 				(unsigned long long)native_sectors);
1540 		else if (native_sectors < sectors)
1541 			ata_dev_printk(dev, KERN_WARNING,
1542 				"native sectors (%llu) is smaller than "
1543 				"sectors (%llu)\n",
1544 				(unsigned long long)native_sectors,
1545 				(unsigned long long)sectors);
1546 		return 0;
1547 	}
1548 
1549 	/* let's unlock HPA */
1550 	rc = ata_set_max_sectors(dev, native_sectors);
1551 	if (rc == -EACCES) {
1552 		/* if device aborted the command, skip HPA resizing */
1553 		ata_dev_printk(dev, KERN_WARNING, "device aborted resize "
1554 			       "(%llu -> %llu), skipping HPA handling\n",
1555 			       (unsigned long long)sectors,
1556 			       (unsigned long long)native_sectors);
1557 		dev->horkage |= ATA_HORKAGE_BROKEN_HPA;
1558 		return 0;
1559 	} else if (rc)
1560 		return rc;
1561 
1562 	/* re-read IDENTIFY data */
1563 	rc = ata_dev_reread_id(dev, 0);
1564 	if (rc) {
1565 		ata_dev_printk(dev, KERN_ERR, "failed to re-read IDENTIFY "
1566 			       "data after HPA resizing\n");
1567 		return rc;
1568 	}
1569 
1570 	if (print_info) {
1571 		u64 new_sectors = ata_id_n_sectors(dev->id);
1572 		ata_dev_printk(dev, KERN_INFO,
1573 			"HPA unlocked: %llu -> %llu, native %llu\n",
1574 			(unsigned long long)sectors,
1575 			(unsigned long long)new_sectors,
1576 			(unsigned long long)native_sectors);
1577 	}
1578 
1579 	return 0;
1580 }
1581 
1582 /**
1583  *	ata_dump_id - IDENTIFY DEVICE info debugging output
1584  *	@id: IDENTIFY DEVICE page to dump
1585  *
1586  *	Dump selected 16-bit words from the given IDENTIFY DEVICE
1587  *	page.
1588  *
1589  *	LOCKING:
1590  *	caller.
1591  */
1592 
1593 static inline void ata_dump_id(const u16 *id)
1594 {
1595 	DPRINTK("49==0x%04x  "
1596 		"53==0x%04x  "
1597 		"63==0x%04x  "
1598 		"64==0x%04x  "
1599 		"75==0x%04x  \n",
1600 		id[49],
1601 		id[53],
1602 		id[63],
1603 		id[64],
1604 		id[75]);
1605 	DPRINTK("80==0x%04x  "
1606 		"81==0x%04x  "
1607 		"82==0x%04x  "
1608 		"83==0x%04x  "
1609 		"84==0x%04x  \n",
1610 		id[80],
1611 		id[81],
1612 		id[82],
1613 		id[83],
1614 		id[84]);
1615 	DPRINTK("88==0x%04x  "
1616 		"93==0x%04x\n",
1617 		id[88],
1618 		id[93]);
1619 }
1620 
1621 /**
1622  *	ata_id_xfermask - Compute xfermask from the given IDENTIFY data
1623  *	@id: IDENTIFY data to compute xfer mask from
1624  *
1625  *	Compute the xfermask for this device. This is not as trivial
1626  *	as it seems if we must consider early devices correctly.
1627  *
1628  *	FIXME: pre IDE drive timing (do we care ?).
1629  *
1630  *	LOCKING:
1631  *	None.
1632  *
1633  *	RETURNS:
1634  *	Computed xfermask
1635  */
1636 unsigned long ata_id_xfermask(const u16 *id)
1637 {
1638 	unsigned long pio_mask, mwdma_mask, udma_mask;
1639 
1640 	/* Usual case. Word 53 indicates word 64 is valid */
1641 	if (id[ATA_ID_FIELD_VALID] & (1 << 1)) {
1642 		pio_mask = id[ATA_ID_PIO_MODES] & 0x03;
1643 		pio_mask <<= 3;
1644 		pio_mask |= 0x7;
1645 	} else {
1646 		/* If word 64 isn't valid then Word 51 high byte holds
1647 		 * the PIO timing number for the maximum. Turn it into
1648 		 * a mask.
1649 		 */
1650 		u8 mode = (id[ATA_ID_OLD_PIO_MODES] >> 8) & 0xFF;
1651 		if (mode < 5)	/* Valid PIO range */
1652 			pio_mask = (2 << mode) - 1;
1653 		else
1654 			pio_mask = 1;
1655 
1656 		/* But wait.. there's more. Design your standards by
1657 		 * committee and you too can get a free iordy field to
1658 		 * process. However its the speeds not the modes that
1659 		 * are supported... Note drivers using the timing API
1660 		 * will get this right anyway
1661 		 */
1662 	}
1663 
1664 	mwdma_mask = id[ATA_ID_MWDMA_MODES] & 0x07;
1665 
1666 	if (ata_id_is_cfa(id)) {
1667 		/*
1668 		 *	Process compact flash extended modes
1669 		 */
1670 		int pio = (id[ATA_ID_CFA_MODES] >> 0) & 0x7;
1671 		int dma = (id[ATA_ID_CFA_MODES] >> 3) & 0x7;
1672 
1673 		if (pio)
1674 			pio_mask |= (1 << 5);
1675 		if (pio > 1)
1676 			pio_mask |= (1 << 6);
1677 		if (dma)
1678 			mwdma_mask |= (1 << 3);
1679 		if (dma > 1)
1680 			mwdma_mask |= (1 << 4);
1681 	}
1682 
1683 	udma_mask = 0;
1684 	if (id[ATA_ID_FIELD_VALID] & (1 << 2))
1685 		udma_mask = id[ATA_ID_UDMA_MODES] & 0xff;
1686 
1687 	return ata_pack_xfermask(pio_mask, mwdma_mask, udma_mask);
1688 }
1689 
1690 static void ata_qc_complete_internal(struct ata_queued_cmd *qc)
1691 {
1692 	struct completion *waiting = qc->private_data;
1693 
1694 	complete(waiting);
1695 }
1696 
1697 /**
1698  *	ata_exec_internal_sg - execute libata internal command
1699  *	@dev: Device to which the command is sent
1700  *	@tf: Taskfile registers for the command and the result
1701  *	@cdb: CDB for packet command
1702  *	@dma_dir: Data tranfer direction of the command
1703  *	@sgl: sg list for the data buffer of the command
1704  *	@n_elem: Number of sg entries
1705  *	@timeout: Timeout in msecs (0 for default)
1706  *
1707  *	Executes libata internal command with timeout.  @tf contains
1708  *	command on entry and result on return.  Timeout and error
1709  *	conditions are reported via return value.  No recovery action
1710  *	is taken after a command times out.  It's caller's duty to
1711  *	clean up after timeout.
1712  *
1713  *	LOCKING:
1714  *	None.  Should be called with kernel context, might sleep.
1715  *
1716  *	RETURNS:
1717  *	Zero on success, AC_ERR_* mask on failure
1718  */
1719 unsigned ata_exec_internal_sg(struct ata_device *dev,
1720 			      struct ata_taskfile *tf, const u8 *cdb,
1721 			      int dma_dir, struct scatterlist *sgl,
1722 			      unsigned int n_elem, unsigned long timeout)
1723 {
1724 	struct ata_link *link = dev->link;
1725 	struct ata_port *ap = link->ap;
1726 	u8 command = tf->command;
1727 	int auto_timeout = 0;
1728 	struct ata_queued_cmd *qc;
1729 	unsigned int tag, preempted_tag;
1730 	u32 preempted_sactive, preempted_qc_active;
1731 	int preempted_nr_active_links;
1732 	DECLARE_COMPLETION_ONSTACK(wait);
1733 	unsigned long flags;
1734 	unsigned int err_mask;
1735 	int rc;
1736 
1737 	spin_lock_irqsave(ap->lock, flags);
1738 
1739 	/* no internal command while frozen */
1740 	if (ap->pflags & ATA_PFLAG_FROZEN) {
1741 		spin_unlock_irqrestore(ap->lock, flags);
1742 		return AC_ERR_SYSTEM;
1743 	}
1744 
1745 	/* initialize internal qc */
1746 
1747 	/* XXX: Tag 0 is used for drivers with legacy EH as some
1748 	 * drivers choke if any other tag is given.  This breaks
1749 	 * ata_tag_internal() test for those drivers.  Don't use new
1750 	 * EH stuff without converting to it.
1751 	 */
1752 	if (ap->ops->error_handler)
1753 		tag = ATA_TAG_INTERNAL;
1754 	else
1755 		tag = 0;
1756 
1757 	if (test_and_set_bit(tag, &ap->qc_allocated))
1758 		BUG();
1759 	qc = __ata_qc_from_tag(ap, tag);
1760 
1761 	qc->tag = tag;
1762 	qc->scsicmd = NULL;
1763 	qc->ap = ap;
1764 	qc->dev = dev;
1765 	ata_qc_reinit(qc);
1766 
1767 	preempted_tag = link->active_tag;
1768 	preempted_sactive = link->sactive;
1769 	preempted_qc_active = ap->qc_active;
1770 	preempted_nr_active_links = ap->nr_active_links;
1771 	link->active_tag = ATA_TAG_POISON;
1772 	link->sactive = 0;
1773 	ap->qc_active = 0;
1774 	ap->nr_active_links = 0;
1775 
1776 	/* prepare & issue qc */
1777 	qc->tf = *tf;
1778 	if (cdb)
1779 		memcpy(qc->cdb, cdb, ATAPI_CDB_LEN);
1780 	qc->flags |= ATA_QCFLAG_RESULT_TF;
1781 	qc->dma_dir = dma_dir;
1782 	if (dma_dir != DMA_NONE) {
1783 		unsigned int i, buflen = 0;
1784 		struct scatterlist *sg;
1785 
1786 		for_each_sg(sgl, sg, n_elem, i)
1787 			buflen += sg->length;
1788 
1789 		ata_sg_init(qc, sgl, n_elem);
1790 		qc->nbytes = buflen;
1791 	}
1792 
1793 	qc->private_data = &wait;
1794 	qc->complete_fn = ata_qc_complete_internal;
1795 
1796 	ata_qc_issue(qc);
1797 
1798 	spin_unlock_irqrestore(ap->lock, flags);
1799 
1800 	if (!timeout) {
1801 		if (ata_probe_timeout)
1802 			timeout = ata_probe_timeout * 1000;
1803 		else {
1804 			timeout = ata_internal_cmd_timeout(dev, command);
1805 			auto_timeout = 1;
1806 		}
1807 	}
1808 
1809 	rc = wait_for_completion_timeout(&wait, msecs_to_jiffies(timeout));
1810 
1811 	ata_sff_flush_pio_task(ap);
1812 
1813 	if (!rc) {
1814 		spin_lock_irqsave(ap->lock, flags);
1815 
1816 		/* We're racing with irq here.  If we lose, the
1817 		 * following test prevents us from completing the qc
1818 		 * twice.  If we win, the port is frozen and will be
1819 		 * cleaned up by ->post_internal_cmd().
1820 		 */
1821 		if (qc->flags & ATA_QCFLAG_ACTIVE) {
1822 			qc->err_mask |= AC_ERR_TIMEOUT;
1823 
1824 			if (ap->ops->error_handler)
1825 				ata_port_freeze(ap);
1826 			else
1827 				ata_qc_complete(qc);
1828 
1829 			if (ata_msg_warn(ap))
1830 				ata_dev_printk(dev, KERN_WARNING,
1831 					"qc timeout (cmd 0x%x)\n", command);
1832 		}
1833 
1834 		spin_unlock_irqrestore(ap->lock, flags);
1835 	}
1836 
1837 	/* do post_internal_cmd */
1838 	if (ap->ops->post_internal_cmd)
1839 		ap->ops->post_internal_cmd(qc);
1840 
1841 	/* perform minimal error analysis */
1842 	if (qc->flags & ATA_QCFLAG_FAILED) {
1843 		if (qc->result_tf.command & (ATA_ERR | ATA_DF))
1844 			qc->err_mask |= AC_ERR_DEV;
1845 
1846 		if (!qc->err_mask)
1847 			qc->err_mask |= AC_ERR_OTHER;
1848 
1849 		if (qc->err_mask & ~AC_ERR_OTHER)
1850 			qc->err_mask &= ~AC_ERR_OTHER;
1851 	}
1852 
1853 	/* finish up */
1854 	spin_lock_irqsave(ap->lock, flags);
1855 
1856 	*tf = qc->result_tf;
1857 	err_mask = qc->err_mask;
1858 
1859 	ata_qc_free(qc);
1860 	link->active_tag = preempted_tag;
1861 	link->sactive = preempted_sactive;
1862 	ap->qc_active = preempted_qc_active;
1863 	ap->nr_active_links = preempted_nr_active_links;
1864 
1865 	spin_unlock_irqrestore(ap->lock, flags);
1866 
1867 	if ((err_mask & AC_ERR_TIMEOUT) && auto_timeout)
1868 		ata_internal_cmd_timed_out(dev, command);
1869 
1870 	return err_mask;
1871 }
1872 
1873 /**
1874  *	ata_exec_internal - execute libata internal command
1875  *	@dev: Device to which the command is sent
1876  *	@tf: Taskfile registers for the command and the result
1877  *	@cdb: CDB for packet command
1878  *	@dma_dir: Data tranfer direction of the command
1879  *	@buf: Data buffer of the command
1880  *	@buflen: Length of data buffer
1881  *	@timeout: Timeout in msecs (0 for default)
1882  *
1883  *	Wrapper around ata_exec_internal_sg() which takes simple
1884  *	buffer instead of sg list.
1885  *
1886  *	LOCKING:
1887  *	None.  Should be called with kernel context, might sleep.
1888  *
1889  *	RETURNS:
1890  *	Zero on success, AC_ERR_* mask on failure
1891  */
1892 unsigned ata_exec_internal(struct ata_device *dev,
1893 			   struct ata_taskfile *tf, const u8 *cdb,
1894 			   int dma_dir, void *buf, unsigned int buflen,
1895 			   unsigned long timeout)
1896 {
1897 	struct scatterlist *psg = NULL, sg;
1898 	unsigned int n_elem = 0;
1899 
1900 	if (dma_dir != DMA_NONE) {
1901 		WARN_ON(!buf);
1902 		sg_init_one(&sg, buf, buflen);
1903 		psg = &sg;
1904 		n_elem++;
1905 	}
1906 
1907 	return ata_exec_internal_sg(dev, tf, cdb, dma_dir, psg, n_elem,
1908 				    timeout);
1909 }
1910 
1911 /**
1912  *	ata_do_simple_cmd - execute simple internal command
1913  *	@dev: Device to which the command is sent
1914  *	@cmd: Opcode to execute
1915  *
1916  *	Execute a 'simple' command, that only consists of the opcode
1917  *	'cmd' itself, without filling any other registers
1918  *
1919  *	LOCKING:
1920  *	Kernel thread context (may sleep).
1921  *
1922  *	RETURNS:
1923  *	Zero on success, AC_ERR_* mask on failure
1924  */
1925 unsigned int ata_do_simple_cmd(struct ata_device *dev, u8 cmd)
1926 {
1927 	struct ata_taskfile tf;
1928 
1929 	ata_tf_init(dev, &tf);
1930 
1931 	tf.command = cmd;
1932 	tf.flags |= ATA_TFLAG_DEVICE;
1933 	tf.protocol = ATA_PROT_NODATA;
1934 
1935 	return ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
1936 }
1937 
1938 /**
1939  *	ata_pio_need_iordy	-	check if iordy needed
1940  *	@adev: ATA device
1941  *
1942  *	Check if the current speed of the device requires IORDY. Used
1943  *	by various controllers for chip configuration.
1944  */
1945 unsigned int ata_pio_need_iordy(const struct ata_device *adev)
1946 {
1947 	/* Don't set IORDY if we're preparing for reset.  IORDY may
1948 	 * lead to controller lock up on certain controllers if the
1949 	 * port is not occupied.  See bko#11703 for details.
1950 	 */
1951 	if (adev->link->ap->pflags & ATA_PFLAG_RESETTING)
1952 		return 0;
1953 	/* Controller doesn't support IORDY.  Probably a pointless
1954 	 * check as the caller should know this.
1955 	 */
1956 	if (adev->link->ap->flags & ATA_FLAG_NO_IORDY)
1957 		return 0;
1958 	/* CF spec. r4.1 Table 22 says no iordy on PIO5 and PIO6.  */
1959 	if (ata_id_is_cfa(adev->id)
1960 	    && (adev->pio_mode == XFER_PIO_5 || adev->pio_mode == XFER_PIO_6))
1961 		return 0;
1962 	/* PIO3 and higher it is mandatory */
1963 	if (adev->pio_mode > XFER_PIO_2)
1964 		return 1;
1965 	/* We turn it on when possible */
1966 	if (ata_id_has_iordy(adev->id))
1967 		return 1;
1968 	return 0;
1969 }
1970 
1971 /**
1972  *	ata_pio_mask_no_iordy	-	Return the non IORDY mask
1973  *	@adev: ATA device
1974  *
1975  *	Compute the highest mode possible if we are not using iordy. Return
1976  *	-1 if no iordy mode is available.
1977  */
1978 static u32 ata_pio_mask_no_iordy(const struct ata_device *adev)
1979 {
1980 	/* If we have no drive specific rule, then PIO 2 is non IORDY */
1981 	if (adev->id[ATA_ID_FIELD_VALID] & 2) {	/* EIDE */
1982 		u16 pio = adev->id[ATA_ID_EIDE_PIO];
1983 		/* Is the speed faster than the drive allows non IORDY ? */
1984 		if (pio) {
1985 			/* This is cycle times not frequency - watch the logic! */
1986 			if (pio > 240)	/* PIO2 is 240nS per cycle */
1987 				return 3 << ATA_SHIFT_PIO;
1988 			return 7 << ATA_SHIFT_PIO;
1989 		}
1990 	}
1991 	return 3 << ATA_SHIFT_PIO;
1992 }
1993 
1994 /**
1995  *	ata_do_dev_read_id		-	default ID read method
1996  *	@dev: device
1997  *	@tf: proposed taskfile
1998  *	@id: data buffer
1999  *
2000  *	Issue the identify taskfile and hand back the buffer containing
2001  *	identify data. For some RAID controllers and for pre ATA devices
2002  *	this function is wrapped or replaced by the driver
2003  */
2004 unsigned int ata_do_dev_read_id(struct ata_device *dev,
2005 					struct ata_taskfile *tf, u16 *id)
2006 {
2007 	return ata_exec_internal(dev, tf, NULL, DMA_FROM_DEVICE,
2008 				     id, sizeof(id[0]) * ATA_ID_WORDS, 0);
2009 }
2010 
2011 /**
2012  *	ata_dev_read_id - Read ID data from the specified device
2013  *	@dev: target device
2014  *	@p_class: pointer to class of the target device (may be changed)
2015  *	@flags: ATA_READID_* flags
2016  *	@id: buffer to read IDENTIFY data into
2017  *
2018  *	Read ID data from the specified device.  ATA_CMD_ID_ATA is
2019  *	performed on ATA devices and ATA_CMD_ID_ATAPI on ATAPI
2020  *	devices.  This function also issues ATA_CMD_INIT_DEV_PARAMS
2021  *	for pre-ATA4 drives.
2022  *
2023  *	FIXME: ATA_CMD_ID_ATA is optional for early drives and right
2024  *	now we abort if we hit that case.
2025  *
2026  *	LOCKING:
2027  *	Kernel thread context (may sleep)
2028  *
2029  *	RETURNS:
2030  *	0 on success, -errno otherwise.
2031  */
2032 int ata_dev_read_id(struct ata_device *dev, unsigned int *p_class,
2033 		    unsigned int flags, u16 *id)
2034 {
2035 	struct ata_port *ap = dev->link->ap;
2036 	unsigned int class = *p_class;
2037 	struct ata_taskfile tf;
2038 	unsigned int err_mask = 0;
2039 	const char *reason;
2040 	bool is_semb = class == ATA_DEV_SEMB;
2041 	int may_fallback = 1, tried_spinup = 0;
2042 	int rc;
2043 
2044 	if (ata_msg_ctl(ap))
2045 		ata_dev_printk(dev, KERN_DEBUG, "%s: ENTER\n", __func__);
2046 
2047 retry:
2048 	ata_tf_init(dev, &tf);
2049 
2050 	switch (class) {
2051 	case ATA_DEV_SEMB:
2052 		class = ATA_DEV_ATA;	/* some hard drives report SEMB sig */
2053 	case ATA_DEV_ATA:
2054 		tf.command = ATA_CMD_ID_ATA;
2055 		break;
2056 	case ATA_DEV_ATAPI:
2057 		tf.command = ATA_CMD_ID_ATAPI;
2058 		break;
2059 	default:
2060 		rc = -ENODEV;
2061 		reason = "unsupported class";
2062 		goto err_out;
2063 	}
2064 
2065 	tf.protocol = ATA_PROT_PIO;
2066 
2067 	/* Some devices choke if TF registers contain garbage.  Make
2068 	 * sure those are properly initialized.
2069 	 */
2070 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
2071 
2072 	/* Device presence detection is unreliable on some
2073 	 * controllers.  Always poll IDENTIFY if available.
2074 	 */
2075 	tf.flags |= ATA_TFLAG_POLLING;
2076 
2077 	if (ap->ops->read_id)
2078 		err_mask = ap->ops->read_id(dev, &tf, id);
2079 	else
2080 		err_mask = ata_do_dev_read_id(dev, &tf, id);
2081 
2082 	if (err_mask) {
2083 		if (err_mask & AC_ERR_NODEV_HINT) {
2084 			ata_dev_printk(dev, KERN_DEBUG,
2085 				       "NODEV after polling detection\n");
2086 			return -ENOENT;
2087 		}
2088 
2089 		if (is_semb) {
2090 			ata_dev_printk(dev, KERN_INFO, "IDENTIFY failed on "
2091 				       "device w/ SEMB sig, disabled\n");
2092 			/* SEMB is not supported yet */
2093 			*p_class = ATA_DEV_SEMB_UNSUP;
2094 			return 0;
2095 		}
2096 
2097 		if ((err_mask == AC_ERR_DEV) && (tf.feature & ATA_ABORTED)) {
2098 			/* Device or controller might have reported
2099 			 * the wrong device class.  Give a shot at the
2100 			 * other IDENTIFY if the current one is
2101 			 * aborted by the device.
2102 			 */
2103 			if (may_fallback) {
2104 				may_fallback = 0;
2105 
2106 				if (class == ATA_DEV_ATA)
2107 					class = ATA_DEV_ATAPI;
2108 				else
2109 					class = ATA_DEV_ATA;
2110 				goto retry;
2111 			}
2112 
2113 			/* Control reaches here iff the device aborted
2114 			 * both flavors of IDENTIFYs which happens
2115 			 * sometimes with phantom devices.
2116 			 */
2117 			ata_dev_printk(dev, KERN_DEBUG,
2118 				       "both IDENTIFYs aborted, assuming NODEV\n");
2119 			return -ENOENT;
2120 		}
2121 
2122 		rc = -EIO;
2123 		reason = "I/O error";
2124 		goto err_out;
2125 	}
2126 
2127 	if (dev->horkage & ATA_HORKAGE_DUMP_ID) {
2128 		ata_dev_printk(dev, KERN_DEBUG, "dumping IDENTIFY data, "
2129 			       "class=%d may_fallback=%d tried_spinup=%d\n",
2130 			       class, may_fallback, tried_spinup);
2131 		print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET,
2132 			       16, 2, id, ATA_ID_WORDS * sizeof(*id), true);
2133 	}
2134 
2135 	/* Falling back doesn't make sense if ID data was read
2136 	 * successfully at least once.
2137 	 */
2138 	may_fallback = 0;
2139 
2140 	swap_buf_le16(id, ATA_ID_WORDS);
2141 
2142 	/* sanity check */
2143 	rc = -EINVAL;
2144 	reason = "device reports invalid type";
2145 
2146 	if (class == ATA_DEV_ATA) {
2147 		if (!ata_id_is_ata(id) && !ata_id_is_cfa(id))
2148 			goto err_out;
2149 	} else {
2150 		if (ata_id_is_ata(id))
2151 			goto err_out;
2152 	}
2153 
2154 	if (!tried_spinup && (id[2] == 0x37c8 || id[2] == 0x738c)) {
2155 		tried_spinup = 1;
2156 		/*
2157 		 * Drive powered-up in standby mode, and requires a specific
2158 		 * SET_FEATURES spin-up subcommand before it will accept
2159 		 * anything other than the original IDENTIFY command.
2160 		 */
2161 		err_mask = ata_dev_set_feature(dev, SETFEATURES_SPINUP, 0);
2162 		if (err_mask && id[2] != 0x738c) {
2163 			rc = -EIO;
2164 			reason = "SPINUP failed";
2165 			goto err_out;
2166 		}
2167 		/*
2168 		 * If the drive initially returned incomplete IDENTIFY info,
2169 		 * we now must reissue the IDENTIFY command.
2170 		 */
2171 		if (id[2] == 0x37c8)
2172 			goto retry;
2173 	}
2174 
2175 	if ((flags & ATA_READID_POSTRESET) && class == ATA_DEV_ATA) {
2176 		/*
2177 		 * The exact sequence expected by certain pre-ATA4 drives is:
2178 		 * SRST RESET
2179 		 * IDENTIFY (optional in early ATA)
2180 		 * INITIALIZE DEVICE PARAMETERS (later IDE and ATA)
2181 		 * anything else..
2182 		 * Some drives were very specific about that exact sequence.
2183 		 *
2184 		 * Note that ATA4 says lba is mandatory so the second check
2185 		 * should never trigger.
2186 		 */
2187 		if (ata_id_major_version(id) < 4 || !ata_id_has_lba(id)) {
2188 			err_mask = ata_dev_init_params(dev, id[3], id[6]);
2189 			if (err_mask) {
2190 				rc = -EIO;
2191 				reason = "INIT_DEV_PARAMS failed";
2192 				goto err_out;
2193 			}
2194 
2195 			/* current CHS translation info (id[53-58]) might be
2196 			 * changed. reread the identify device info.
2197 			 */
2198 			flags &= ~ATA_READID_POSTRESET;
2199 			goto retry;
2200 		}
2201 	}
2202 
2203 	*p_class = class;
2204 
2205 	return 0;
2206 
2207  err_out:
2208 	if (ata_msg_warn(ap))
2209 		ata_dev_printk(dev, KERN_WARNING, "failed to IDENTIFY "
2210 			       "(%s, err_mask=0x%x)\n", reason, err_mask);
2211 	return rc;
2212 }
2213 
2214 static int ata_do_link_spd_horkage(struct ata_device *dev)
2215 {
2216 	struct ata_link *plink = ata_dev_phys_link(dev);
2217 	u32 target, target_limit;
2218 
2219 	if (!sata_scr_valid(plink))
2220 		return 0;
2221 
2222 	if (dev->horkage & ATA_HORKAGE_1_5_GBPS)
2223 		target = 1;
2224 	else
2225 		return 0;
2226 
2227 	target_limit = (1 << target) - 1;
2228 
2229 	/* if already on stricter limit, no need to push further */
2230 	if (plink->sata_spd_limit <= target_limit)
2231 		return 0;
2232 
2233 	plink->sata_spd_limit = target_limit;
2234 
2235 	/* Request another EH round by returning -EAGAIN if link is
2236 	 * going faster than the target speed.  Forward progress is
2237 	 * guaranteed by setting sata_spd_limit to target_limit above.
2238 	 */
2239 	if (plink->sata_spd > target) {
2240 		ata_dev_printk(dev, KERN_INFO,
2241 			       "applying link speed limit horkage to %s\n",
2242 			       sata_spd_string(target));
2243 		return -EAGAIN;
2244 	}
2245 	return 0;
2246 }
2247 
2248 static inline u8 ata_dev_knobble(struct ata_device *dev)
2249 {
2250 	struct ata_port *ap = dev->link->ap;
2251 
2252 	if (ata_dev_blacklisted(dev) & ATA_HORKAGE_BRIDGE_OK)
2253 		return 0;
2254 
2255 	return ((ap->cbl == ATA_CBL_SATA) && (!ata_id_is_sata(dev->id)));
2256 }
2257 
2258 static int ata_dev_config_ncq(struct ata_device *dev,
2259 			       char *desc, size_t desc_sz)
2260 {
2261 	struct ata_port *ap = dev->link->ap;
2262 	int hdepth = 0, ddepth = ata_id_queue_depth(dev->id);
2263 	unsigned int err_mask;
2264 	char *aa_desc = "";
2265 
2266 	if (!ata_id_has_ncq(dev->id)) {
2267 		desc[0] = '\0';
2268 		return 0;
2269 	}
2270 	if (dev->horkage & ATA_HORKAGE_NONCQ) {
2271 		snprintf(desc, desc_sz, "NCQ (not used)");
2272 		return 0;
2273 	}
2274 	if (ap->flags & ATA_FLAG_NCQ) {
2275 		hdepth = min(ap->scsi_host->can_queue, ATA_MAX_QUEUE - 1);
2276 		dev->flags |= ATA_DFLAG_NCQ;
2277 	}
2278 
2279 	if (!(dev->horkage & ATA_HORKAGE_BROKEN_FPDMA_AA) &&
2280 		(ap->flags & ATA_FLAG_FPDMA_AA) &&
2281 		ata_id_has_fpdma_aa(dev->id)) {
2282 		err_mask = ata_dev_set_feature(dev, SETFEATURES_SATA_ENABLE,
2283 			SATA_FPDMA_AA);
2284 		if (err_mask) {
2285 			ata_dev_printk(dev, KERN_ERR, "failed to enable AA"
2286 				"(error_mask=0x%x)\n", err_mask);
2287 			if (err_mask != AC_ERR_DEV) {
2288 				dev->horkage |= ATA_HORKAGE_BROKEN_FPDMA_AA;
2289 				return -EIO;
2290 			}
2291 		} else
2292 			aa_desc = ", AA";
2293 	}
2294 
2295 	if (hdepth >= ddepth)
2296 		snprintf(desc, desc_sz, "NCQ (depth %d)%s", ddepth, aa_desc);
2297 	else
2298 		snprintf(desc, desc_sz, "NCQ (depth %d/%d)%s", hdepth,
2299 			ddepth, aa_desc);
2300 	return 0;
2301 }
2302 
2303 /**
2304  *	ata_dev_configure - Configure the specified ATA/ATAPI device
2305  *	@dev: Target device to configure
2306  *
2307  *	Configure @dev according to @dev->id.  Generic and low-level
2308  *	driver specific fixups are also applied.
2309  *
2310  *	LOCKING:
2311  *	Kernel thread context (may sleep)
2312  *
2313  *	RETURNS:
2314  *	0 on success, -errno otherwise
2315  */
2316 int ata_dev_configure(struct ata_device *dev)
2317 {
2318 	struct ata_port *ap = dev->link->ap;
2319 	struct ata_eh_context *ehc = &dev->link->eh_context;
2320 	int print_info = ehc->i.flags & ATA_EHI_PRINTINFO;
2321 	const u16 *id = dev->id;
2322 	unsigned long xfer_mask;
2323 	char revbuf[7];		/* XYZ-99\0 */
2324 	char fwrevbuf[ATA_ID_FW_REV_LEN+1];
2325 	char modelbuf[ATA_ID_PROD_LEN+1];
2326 	int rc;
2327 
2328 	if (!ata_dev_enabled(dev) && ata_msg_info(ap)) {
2329 		ata_dev_printk(dev, KERN_INFO, "%s: ENTER/EXIT -- nodev\n",
2330 			       __func__);
2331 		return 0;
2332 	}
2333 
2334 	if (ata_msg_probe(ap))
2335 		ata_dev_printk(dev, KERN_DEBUG, "%s: ENTER\n", __func__);
2336 
2337 	/* set horkage */
2338 	dev->horkage |= ata_dev_blacklisted(dev);
2339 	ata_force_horkage(dev);
2340 
2341 	if (dev->horkage & ATA_HORKAGE_DISABLE) {
2342 		ata_dev_printk(dev, KERN_INFO,
2343 			       "unsupported device, disabling\n");
2344 		ata_dev_disable(dev);
2345 		return 0;
2346 	}
2347 
2348 	if ((!atapi_enabled || (ap->flags & ATA_FLAG_NO_ATAPI)) &&
2349 	    dev->class == ATA_DEV_ATAPI) {
2350 		ata_dev_printk(dev, KERN_WARNING,
2351 			"WARNING: ATAPI is %s, device ignored.\n",
2352 			atapi_enabled ? "not supported with this driver"
2353 				      : "disabled");
2354 		ata_dev_disable(dev);
2355 		return 0;
2356 	}
2357 
2358 	rc = ata_do_link_spd_horkage(dev);
2359 	if (rc)
2360 		return rc;
2361 
2362 	/* let ACPI work its magic */
2363 	rc = ata_acpi_on_devcfg(dev);
2364 	if (rc)
2365 		return rc;
2366 
2367 	/* massage HPA, do it early as it might change IDENTIFY data */
2368 	rc = ata_hpa_resize(dev);
2369 	if (rc)
2370 		return rc;
2371 
2372 	/* print device capabilities */
2373 	if (ata_msg_probe(ap))
2374 		ata_dev_printk(dev, KERN_DEBUG,
2375 			       "%s: cfg 49:%04x 82:%04x 83:%04x 84:%04x "
2376 			       "85:%04x 86:%04x 87:%04x 88:%04x\n",
2377 			       __func__,
2378 			       id[49], id[82], id[83], id[84],
2379 			       id[85], id[86], id[87], id[88]);
2380 
2381 	/* initialize to-be-configured parameters */
2382 	dev->flags &= ~ATA_DFLAG_CFG_MASK;
2383 	dev->max_sectors = 0;
2384 	dev->cdb_len = 0;
2385 	dev->n_sectors = 0;
2386 	dev->cylinders = 0;
2387 	dev->heads = 0;
2388 	dev->sectors = 0;
2389 	dev->multi_count = 0;
2390 
2391 	/*
2392 	 * common ATA, ATAPI feature tests
2393 	 */
2394 
2395 	/* find max transfer mode; for printk only */
2396 	xfer_mask = ata_id_xfermask(id);
2397 
2398 	if (ata_msg_probe(ap))
2399 		ata_dump_id(id);
2400 
2401 	/* SCSI only uses 4-char revisions, dump full 8 chars from ATA */
2402 	ata_id_c_string(dev->id, fwrevbuf, ATA_ID_FW_REV,
2403 			sizeof(fwrevbuf));
2404 
2405 	ata_id_c_string(dev->id, modelbuf, ATA_ID_PROD,
2406 			sizeof(modelbuf));
2407 
2408 	/* ATA-specific feature tests */
2409 	if (dev->class == ATA_DEV_ATA) {
2410 		if (ata_id_is_cfa(id)) {
2411 			/* CPRM may make this media unusable */
2412 			if (id[ATA_ID_CFA_KEY_MGMT] & 1)
2413 				ata_dev_printk(dev, KERN_WARNING,
2414 					       "supports DRM functions and may "
2415 					       "not be fully accessable.\n");
2416 			snprintf(revbuf, 7, "CFA");
2417 		} else {
2418 			snprintf(revbuf, 7, "ATA-%d", ata_id_major_version(id));
2419 			/* Warn the user if the device has TPM extensions */
2420 			if (ata_id_has_tpm(id))
2421 				ata_dev_printk(dev, KERN_WARNING,
2422 					       "supports DRM functions and may "
2423 					       "not be fully accessable.\n");
2424 		}
2425 
2426 		dev->n_sectors = ata_id_n_sectors(id);
2427 
2428 		/* get current R/W Multiple count setting */
2429 		if ((dev->id[47] >> 8) == 0x80 && (dev->id[59] & 0x100)) {
2430 			unsigned int max = dev->id[47] & 0xff;
2431 			unsigned int cnt = dev->id[59] & 0xff;
2432 			/* only recognize/allow powers of two here */
2433 			if (is_power_of_2(max) && is_power_of_2(cnt))
2434 				if (cnt <= max)
2435 					dev->multi_count = cnt;
2436 		}
2437 
2438 		if (ata_id_has_lba(id)) {
2439 			const char *lba_desc;
2440 			char ncq_desc[24];
2441 
2442 			lba_desc = "LBA";
2443 			dev->flags |= ATA_DFLAG_LBA;
2444 			if (ata_id_has_lba48(id)) {
2445 				dev->flags |= ATA_DFLAG_LBA48;
2446 				lba_desc = "LBA48";
2447 
2448 				if (dev->n_sectors >= (1UL << 28) &&
2449 				    ata_id_has_flush_ext(id))
2450 					dev->flags |= ATA_DFLAG_FLUSH_EXT;
2451 			}
2452 
2453 			/* config NCQ */
2454 			rc = ata_dev_config_ncq(dev, ncq_desc, sizeof(ncq_desc));
2455 			if (rc)
2456 				return rc;
2457 
2458 			/* print device info to dmesg */
2459 			if (ata_msg_drv(ap) && print_info) {
2460 				ata_dev_printk(dev, KERN_INFO,
2461 					"%s: %s, %s, max %s\n",
2462 					revbuf, modelbuf, fwrevbuf,
2463 					ata_mode_string(xfer_mask));
2464 				ata_dev_printk(dev, KERN_INFO,
2465 					"%Lu sectors, multi %u: %s %s\n",
2466 					(unsigned long long)dev->n_sectors,
2467 					dev->multi_count, lba_desc, ncq_desc);
2468 			}
2469 		} else {
2470 			/* CHS */
2471 
2472 			/* Default translation */
2473 			dev->cylinders	= id[1];
2474 			dev->heads	= id[3];
2475 			dev->sectors	= id[6];
2476 
2477 			if (ata_id_current_chs_valid(id)) {
2478 				/* Current CHS translation is valid. */
2479 				dev->cylinders = id[54];
2480 				dev->heads     = id[55];
2481 				dev->sectors   = id[56];
2482 			}
2483 
2484 			/* print device info to dmesg */
2485 			if (ata_msg_drv(ap) && print_info) {
2486 				ata_dev_printk(dev, KERN_INFO,
2487 					"%s: %s, %s, max %s\n",
2488 					revbuf,	modelbuf, fwrevbuf,
2489 					ata_mode_string(xfer_mask));
2490 				ata_dev_printk(dev, KERN_INFO,
2491 					"%Lu sectors, multi %u, CHS %u/%u/%u\n",
2492 					(unsigned long long)dev->n_sectors,
2493 					dev->multi_count, dev->cylinders,
2494 					dev->heads, dev->sectors);
2495 			}
2496 		}
2497 
2498 		dev->cdb_len = 16;
2499 	}
2500 
2501 	/* ATAPI-specific feature tests */
2502 	else if (dev->class == ATA_DEV_ATAPI) {
2503 		const char *cdb_intr_string = "";
2504 		const char *atapi_an_string = "";
2505 		const char *dma_dir_string = "";
2506 		u32 sntf;
2507 
2508 		rc = atapi_cdb_len(id);
2509 		if ((rc < 12) || (rc > ATAPI_CDB_LEN)) {
2510 			if (ata_msg_warn(ap))
2511 				ata_dev_printk(dev, KERN_WARNING,
2512 					       "unsupported CDB len\n");
2513 			rc = -EINVAL;
2514 			goto err_out_nosup;
2515 		}
2516 		dev->cdb_len = (unsigned int) rc;
2517 
2518 		/* Enable ATAPI AN if both the host and device have
2519 		 * the support.  If PMP is attached, SNTF is required
2520 		 * to enable ATAPI AN to discern between PHY status
2521 		 * changed notifications and ATAPI ANs.
2522 		 */
2523 		if (atapi_an &&
2524 		    (ap->flags & ATA_FLAG_AN) && ata_id_has_atapi_AN(id) &&
2525 		    (!sata_pmp_attached(ap) ||
2526 		     sata_scr_read(&ap->link, SCR_NOTIFICATION, &sntf) == 0)) {
2527 			unsigned int err_mask;
2528 
2529 			/* issue SET feature command to turn this on */
2530 			err_mask = ata_dev_set_feature(dev,
2531 					SETFEATURES_SATA_ENABLE, SATA_AN);
2532 			if (err_mask)
2533 				ata_dev_printk(dev, KERN_ERR,
2534 					"failed to enable ATAPI AN "
2535 					"(err_mask=0x%x)\n", err_mask);
2536 			else {
2537 				dev->flags |= ATA_DFLAG_AN;
2538 				atapi_an_string = ", ATAPI AN";
2539 			}
2540 		}
2541 
2542 		if (ata_id_cdb_intr(dev->id)) {
2543 			dev->flags |= ATA_DFLAG_CDB_INTR;
2544 			cdb_intr_string = ", CDB intr";
2545 		}
2546 
2547 		if (atapi_dmadir || atapi_id_dmadir(dev->id)) {
2548 			dev->flags |= ATA_DFLAG_DMADIR;
2549 			dma_dir_string = ", DMADIR";
2550 		}
2551 
2552 		/* print device info to dmesg */
2553 		if (ata_msg_drv(ap) && print_info)
2554 			ata_dev_printk(dev, KERN_INFO,
2555 				       "ATAPI: %s, %s, max %s%s%s%s\n",
2556 				       modelbuf, fwrevbuf,
2557 				       ata_mode_string(xfer_mask),
2558 				       cdb_intr_string, atapi_an_string,
2559 				       dma_dir_string);
2560 	}
2561 
2562 	/* determine max_sectors */
2563 	dev->max_sectors = ATA_MAX_SECTORS;
2564 	if (dev->flags & ATA_DFLAG_LBA48)
2565 		dev->max_sectors = ATA_MAX_SECTORS_LBA48;
2566 
2567 	if (!(dev->horkage & ATA_HORKAGE_IPM)) {
2568 		if (ata_id_has_hipm(dev->id))
2569 			dev->flags |= ATA_DFLAG_HIPM;
2570 		if (ata_id_has_dipm(dev->id))
2571 			dev->flags |= ATA_DFLAG_DIPM;
2572 	}
2573 
2574 	/* Limit PATA drive on SATA cable bridge transfers to udma5,
2575 	   200 sectors */
2576 	if (ata_dev_knobble(dev)) {
2577 		if (ata_msg_drv(ap) && print_info)
2578 			ata_dev_printk(dev, KERN_INFO,
2579 				       "applying bridge limits\n");
2580 		dev->udma_mask &= ATA_UDMA5;
2581 		dev->max_sectors = ATA_MAX_SECTORS;
2582 	}
2583 
2584 	if ((dev->class == ATA_DEV_ATAPI) &&
2585 	    (atapi_command_packet_set(id) == TYPE_TAPE)) {
2586 		dev->max_sectors = ATA_MAX_SECTORS_TAPE;
2587 		dev->horkage |= ATA_HORKAGE_STUCK_ERR;
2588 	}
2589 
2590 	if (dev->horkage & ATA_HORKAGE_MAX_SEC_128)
2591 		dev->max_sectors = min_t(unsigned int, ATA_MAX_SECTORS_128,
2592 					 dev->max_sectors);
2593 
2594 	if (ata_dev_blacklisted(dev) & ATA_HORKAGE_IPM) {
2595 		dev->horkage |= ATA_HORKAGE_IPM;
2596 
2597 		/* reset link pm_policy for this port to no pm */
2598 		ap->pm_policy = MAX_PERFORMANCE;
2599 	}
2600 
2601 	if (ap->ops->dev_config)
2602 		ap->ops->dev_config(dev);
2603 
2604 	if (dev->horkage & ATA_HORKAGE_DIAGNOSTIC) {
2605 		/* Let the user know. We don't want to disallow opens for
2606 		   rescue purposes, or in case the vendor is just a blithering
2607 		   idiot. Do this after the dev_config call as some controllers
2608 		   with buggy firmware may want to avoid reporting false device
2609 		   bugs */
2610 
2611 		if (print_info) {
2612 			ata_dev_printk(dev, KERN_WARNING,
2613 "Drive reports diagnostics failure. This may indicate a drive\n");
2614 			ata_dev_printk(dev, KERN_WARNING,
2615 "fault or invalid emulation. Contact drive vendor for information.\n");
2616 		}
2617 	}
2618 
2619 	if ((dev->horkage & ATA_HORKAGE_FIRMWARE_WARN) && print_info) {
2620 		ata_dev_printk(dev, KERN_WARNING, "WARNING: device requires "
2621 			       "firmware update to be fully functional.\n");
2622 		ata_dev_printk(dev, KERN_WARNING, "         contact the vendor "
2623 			       "or visit http://ata.wiki.kernel.org.\n");
2624 	}
2625 
2626 	return 0;
2627 
2628 err_out_nosup:
2629 	if (ata_msg_probe(ap))
2630 		ata_dev_printk(dev, KERN_DEBUG,
2631 			       "%s: EXIT, err\n", __func__);
2632 	return rc;
2633 }
2634 
2635 /**
2636  *	ata_cable_40wire	-	return 40 wire cable type
2637  *	@ap: port
2638  *
2639  *	Helper method for drivers which want to hardwire 40 wire cable
2640  *	detection.
2641  */
2642 
2643 int ata_cable_40wire(struct ata_port *ap)
2644 {
2645 	return ATA_CBL_PATA40;
2646 }
2647 
2648 /**
2649  *	ata_cable_80wire	-	return 80 wire cable type
2650  *	@ap: port
2651  *
2652  *	Helper method for drivers which want to hardwire 80 wire cable
2653  *	detection.
2654  */
2655 
2656 int ata_cable_80wire(struct ata_port *ap)
2657 {
2658 	return ATA_CBL_PATA80;
2659 }
2660 
2661 /**
2662  *	ata_cable_unknown	-	return unknown PATA cable.
2663  *	@ap: port
2664  *
2665  *	Helper method for drivers which have no PATA cable detection.
2666  */
2667 
2668 int ata_cable_unknown(struct ata_port *ap)
2669 {
2670 	return ATA_CBL_PATA_UNK;
2671 }
2672 
2673 /**
2674  *	ata_cable_ignore	-	return ignored PATA cable.
2675  *	@ap: port
2676  *
2677  *	Helper method for drivers which don't use cable type to limit
2678  *	transfer mode.
2679  */
2680 int ata_cable_ignore(struct ata_port *ap)
2681 {
2682 	return ATA_CBL_PATA_IGN;
2683 }
2684 
2685 /**
2686  *	ata_cable_sata	-	return SATA cable type
2687  *	@ap: port
2688  *
2689  *	Helper method for drivers which have SATA cables
2690  */
2691 
2692 int ata_cable_sata(struct ata_port *ap)
2693 {
2694 	return ATA_CBL_SATA;
2695 }
2696 
2697 /**
2698  *	ata_bus_probe - Reset and probe ATA bus
2699  *	@ap: Bus to probe
2700  *
2701  *	Master ATA bus probing function.  Initiates a hardware-dependent
2702  *	bus reset, then attempts to identify any devices found on
2703  *	the bus.
2704  *
2705  *	LOCKING:
2706  *	PCI/etc. bus probe sem.
2707  *
2708  *	RETURNS:
2709  *	Zero on success, negative errno otherwise.
2710  */
2711 
2712 int ata_bus_probe(struct ata_port *ap)
2713 {
2714 	unsigned int classes[ATA_MAX_DEVICES];
2715 	int tries[ATA_MAX_DEVICES];
2716 	int rc;
2717 	struct ata_device *dev;
2718 
2719 	ata_for_each_dev(dev, &ap->link, ALL)
2720 		tries[dev->devno] = ATA_PROBE_MAX_TRIES;
2721 
2722  retry:
2723 	ata_for_each_dev(dev, &ap->link, ALL) {
2724 		/* If we issue an SRST then an ATA drive (not ATAPI)
2725 		 * may change configuration and be in PIO0 timing. If
2726 		 * we do a hard reset (or are coming from power on)
2727 		 * this is true for ATA or ATAPI. Until we've set a
2728 		 * suitable controller mode we should not touch the
2729 		 * bus as we may be talking too fast.
2730 		 */
2731 		dev->pio_mode = XFER_PIO_0;
2732 
2733 		/* If the controller has a pio mode setup function
2734 		 * then use it to set the chipset to rights. Don't
2735 		 * touch the DMA setup as that will be dealt with when
2736 		 * configuring devices.
2737 		 */
2738 		if (ap->ops->set_piomode)
2739 			ap->ops->set_piomode(ap, dev);
2740 	}
2741 
2742 	/* reset and determine device classes */
2743 	ap->ops->phy_reset(ap);
2744 
2745 	ata_for_each_dev(dev, &ap->link, ALL) {
2746 		if (dev->class != ATA_DEV_UNKNOWN)
2747 			classes[dev->devno] = dev->class;
2748 		else
2749 			classes[dev->devno] = ATA_DEV_NONE;
2750 
2751 		dev->class = ATA_DEV_UNKNOWN;
2752 	}
2753 
2754 	/* read IDENTIFY page and configure devices. We have to do the identify
2755 	   specific sequence bass-ackwards so that PDIAG- is released by
2756 	   the slave device */
2757 
2758 	ata_for_each_dev(dev, &ap->link, ALL_REVERSE) {
2759 		if (tries[dev->devno])
2760 			dev->class = classes[dev->devno];
2761 
2762 		if (!ata_dev_enabled(dev))
2763 			continue;
2764 
2765 		rc = ata_dev_read_id(dev, &dev->class, ATA_READID_POSTRESET,
2766 				     dev->id);
2767 		if (rc)
2768 			goto fail;
2769 	}
2770 
2771 	/* Now ask for the cable type as PDIAG- should have been released */
2772 	if (ap->ops->cable_detect)
2773 		ap->cbl = ap->ops->cable_detect(ap);
2774 
2775 	/* We may have SATA bridge glue hiding here irrespective of
2776 	 * the reported cable types and sensed types.  When SATA
2777 	 * drives indicate we have a bridge, we don't know which end
2778 	 * of the link the bridge is which is a problem.
2779 	 */
2780 	ata_for_each_dev(dev, &ap->link, ENABLED)
2781 		if (ata_id_is_sata(dev->id))
2782 			ap->cbl = ATA_CBL_SATA;
2783 
2784 	/* After the identify sequence we can now set up the devices. We do
2785 	   this in the normal order so that the user doesn't get confused */
2786 
2787 	ata_for_each_dev(dev, &ap->link, ENABLED) {
2788 		ap->link.eh_context.i.flags |= ATA_EHI_PRINTINFO;
2789 		rc = ata_dev_configure(dev);
2790 		ap->link.eh_context.i.flags &= ~ATA_EHI_PRINTINFO;
2791 		if (rc)
2792 			goto fail;
2793 	}
2794 
2795 	/* configure transfer mode */
2796 	rc = ata_set_mode(&ap->link, &dev);
2797 	if (rc)
2798 		goto fail;
2799 
2800 	ata_for_each_dev(dev, &ap->link, ENABLED)
2801 		return 0;
2802 
2803 	return -ENODEV;
2804 
2805  fail:
2806 	tries[dev->devno]--;
2807 
2808 	switch (rc) {
2809 	case -EINVAL:
2810 		/* eeek, something went very wrong, give up */
2811 		tries[dev->devno] = 0;
2812 		break;
2813 
2814 	case -ENODEV:
2815 		/* give it just one more chance */
2816 		tries[dev->devno] = min(tries[dev->devno], 1);
2817 	case -EIO:
2818 		if (tries[dev->devno] == 1) {
2819 			/* This is the last chance, better to slow
2820 			 * down than lose it.
2821 			 */
2822 			sata_down_spd_limit(&ap->link, 0);
2823 			ata_down_xfermask_limit(dev, ATA_DNXFER_PIO);
2824 		}
2825 	}
2826 
2827 	if (!tries[dev->devno])
2828 		ata_dev_disable(dev);
2829 
2830 	goto retry;
2831 }
2832 
2833 /**
2834  *	sata_print_link_status - Print SATA link status
2835  *	@link: SATA link to printk link status about
2836  *
2837  *	This function prints link speed and status of a SATA link.
2838  *
2839  *	LOCKING:
2840  *	None.
2841  */
2842 static void sata_print_link_status(struct ata_link *link)
2843 {
2844 	u32 sstatus, scontrol, tmp;
2845 
2846 	if (sata_scr_read(link, SCR_STATUS, &sstatus))
2847 		return;
2848 	sata_scr_read(link, SCR_CONTROL, &scontrol);
2849 
2850 	if (ata_phys_link_online(link)) {
2851 		tmp = (sstatus >> 4) & 0xf;
2852 		ata_link_printk(link, KERN_INFO,
2853 				"SATA link up %s (SStatus %X SControl %X)\n",
2854 				sata_spd_string(tmp), sstatus, scontrol);
2855 	} else {
2856 		ata_link_printk(link, KERN_INFO,
2857 				"SATA link down (SStatus %X SControl %X)\n",
2858 				sstatus, scontrol);
2859 	}
2860 }
2861 
2862 /**
2863  *	ata_dev_pair		-	return other device on cable
2864  *	@adev: device
2865  *
2866  *	Obtain the other device on the same cable, or if none is
2867  *	present NULL is returned
2868  */
2869 
2870 struct ata_device *ata_dev_pair(struct ata_device *adev)
2871 {
2872 	struct ata_link *link = adev->link;
2873 	struct ata_device *pair = &link->device[1 - adev->devno];
2874 	if (!ata_dev_enabled(pair))
2875 		return NULL;
2876 	return pair;
2877 }
2878 
2879 /**
2880  *	sata_down_spd_limit - adjust SATA spd limit downward
2881  *	@link: Link to adjust SATA spd limit for
2882  *	@spd_limit: Additional limit
2883  *
2884  *	Adjust SATA spd limit of @link downward.  Note that this
2885  *	function only adjusts the limit.  The change must be applied
2886  *	using sata_set_spd().
2887  *
2888  *	If @spd_limit is non-zero, the speed is limited to equal to or
2889  *	lower than @spd_limit if such speed is supported.  If
2890  *	@spd_limit is slower than any supported speed, only the lowest
2891  *	supported speed is allowed.
2892  *
2893  *	LOCKING:
2894  *	Inherited from caller.
2895  *
2896  *	RETURNS:
2897  *	0 on success, negative errno on failure
2898  */
2899 int sata_down_spd_limit(struct ata_link *link, u32 spd_limit)
2900 {
2901 	u32 sstatus, spd, mask;
2902 	int rc, bit;
2903 
2904 	if (!sata_scr_valid(link))
2905 		return -EOPNOTSUPP;
2906 
2907 	/* If SCR can be read, use it to determine the current SPD.
2908 	 * If not, use cached value in link->sata_spd.
2909 	 */
2910 	rc = sata_scr_read(link, SCR_STATUS, &sstatus);
2911 	if (rc == 0 && ata_sstatus_online(sstatus))
2912 		spd = (sstatus >> 4) & 0xf;
2913 	else
2914 		spd = link->sata_spd;
2915 
2916 	mask = link->sata_spd_limit;
2917 	if (mask <= 1)
2918 		return -EINVAL;
2919 
2920 	/* unconditionally mask off the highest bit */
2921 	bit = fls(mask) - 1;
2922 	mask &= ~(1 << bit);
2923 
2924 	/* Mask off all speeds higher than or equal to the current
2925 	 * one.  Force 1.5Gbps if current SPD is not available.
2926 	 */
2927 	if (spd > 1)
2928 		mask &= (1 << (spd - 1)) - 1;
2929 	else
2930 		mask &= 1;
2931 
2932 	/* were we already at the bottom? */
2933 	if (!mask)
2934 		return -EINVAL;
2935 
2936 	if (spd_limit) {
2937 		if (mask & ((1 << spd_limit) - 1))
2938 			mask &= (1 << spd_limit) - 1;
2939 		else {
2940 			bit = ffs(mask) - 1;
2941 			mask = 1 << bit;
2942 		}
2943 	}
2944 
2945 	link->sata_spd_limit = mask;
2946 
2947 	ata_link_printk(link, KERN_WARNING, "limiting SATA link speed to %s\n",
2948 			sata_spd_string(fls(mask)));
2949 
2950 	return 0;
2951 }
2952 
2953 static int __sata_set_spd_needed(struct ata_link *link, u32 *scontrol)
2954 {
2955 	struct ata_link *host_link = &link->ap->link;
2956 	u32 limit, target, spd;
2957 
2958 	limit = link->sata_spd_limit;
2959 
2960 	/* Don't configure downstream link faster than upstream link.
2961 	 * It doesn't speed up anything and some PMPs choke on such
2962 	 * configuration.
2963 	 */
2964 	if (!ata_is_host_link(link) && host_link->sata_spd)
2965 		limit &= (1 << host_link->sata_spd) - 1;
2966 
2967 	if (limit == UINT_MAX)
2968 		target = 0;
2969 	else
2970 		target = fls(limit);
2971 
2972 	spd = (*scontrol >> 4) & 0xf;
2973 	*scontrol = (*scontrol & ~0xf0) | ((target & 0xf) << 4);
2974 
2975 	return spd != target;
2976 }
2977 
2978 /**
2979  *	sata_set_spd_needed - is SATA spd configuration needed
2980  *	@link: Link in question
2981  *
2982  *	Test whether the spd limit in SControl matches
2983  *	@link->sata_spd_limit.  This function is used to determine
2984  *	whether hardreset is necessary to apply SATA spd
2985  *	configuration.
2986  *
2987  *	LOCKING:
2988  *	Inherited from caller.
2989  *
2990  *	RETURNS:
2991  *	1 if SATA spd configuration is needed, 0 otherwise.
2992  */
2993 static int sata_set_spd_needed(struct ata_link *link)
2994 {
2995 	u32 scontrol;
2996 
2997 	if (sata_scr_read(link, SCR_CONTROL, &scontrol))
2998 		return 1;
2999 
3000 	return __sata_set_spd_needed(link, &scontrol);
3001 }
3002 
3003 /**
3004  *	sata_set_spd - set SATA spd according to spd limit
3005  *	@link: Link to set SATA spd for
3006  *
3007  *	Set SATA spd of @link according to sata_spd_limit.
3008  *
3009  *	LOCKING:
3010  *	Inherited from caller.
3011  *
3012  *	RETURNS:
3013  *	0 if spd doesn't need to be changed, 1 if spd has been
3014  *	changed.  Negative errno if SCR registers are inaccessible.
3015  */
3016 int sata_set_spd(struct ata_link *link)
3017 {
3018 	u32 scontrol;
3019 	int rc;
3020 
3021 	if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3022 		return rc;
3023 
3024 	if (!__sata_set_spd_needed(link, &scontrol))
3025 		return 0;
3026 
3027 	if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
3028 		return rc;
3029 
3030 	return 1;
3031 }
3032 
3033 /*
3034  * This mode timing computation functionality is ported over from
3035  * drivers/ide/ide-timing.h and was originally written by Vojtech Pavlik
3036  */
3037 /*
3038  * PIO 0-4, MWDMA 0-2 and UDMA 0-6 timings (in nanoseconds).
3039  * These were taken from ATA/ATAPI-6 standard, rev 0a, except
3040  * for UDMA6, which is currently supported only by Maxtor drives.
3041  *
3042  * For PIO 5/6 MWDMA 3/4 see the CFA specification 3.0.
3043  */
3044 
3045 static const struct ata_timing ata_timing[] = {
3046 /*	{ XFER_PIO_SLOW, 120, 290, 240, 960, 290, 240, 0,  960,   0 }, */
3047 	{ XFER_PIO_0,     70, 290, 240, 600, 165, 150, 0,  600,   0 },
3048 	{ XFER_PIO_1,     50, 290,  93, 383, 125, 100, 0,  383,   0 },
3049 	{ XFER_PIO_2,     30, 290,  40, 330, 100,  90, 0,  240,   0 },
3050 	{ XFER_PIO_3,     30,  80,  70, 180,  80,  70, 0,  180,   0 },
3051 	{ XFER_PIO_4,     25,  70,  25, 120,  70,  25, 0,  120,   0 },
3052 	{ XFER_PIO_5,     15,  65,  25, 100,  65,  25, 0,  100,   0 },
3053 	{ XFER_PIO_6,     10,  55,  20,  80,  55,  20, 0,   80,   0 },
3054 
3055 	{ XFER_SW_DMA_0, 120,   0,   0,   0, 480, 480, 50, 960,   0 },
3056 	{ XFER_SW_DMA_1,  90,   0,   0,   0, 240, 240, 30, 480,   0 },
3057 	{ XFER_SW_DMA_2,  60,   0,   0,   0, 120, 120, 20, 240,   0 },
3058 
3059 	{ XFER_MW_DMA_0,  60,   0,   0,   0, 215, 215, 20, 480,   0 },
3060 	{ XFER_MW_DMA_1,  45,   0,   0,   0,  80,  50, 5,  150,   0 },
3061 	{ XFER_MW_DMA_2,  25,   0,   0,   0,  70,  25, 5,  120,   0 },
3062 	{ XFER_MW_DMA_3,  25,   0,   0,   0,  65,  25, 5,  100,   0 },
3063 	{ XFER_MW_DMA_4,  25,   0,   0,   0,  55,  20, 5,   80,   0 },
3064 
3065 /*	{ XFER_UDMA_SLOW,  0,   0,   0,   0,   0,   0, 0,    0, 150 }, */
3066 	{ XFER_UDMA_0,     0,   0,   0,   0,   0,   0, 0,    0, 120 },
3067 	{ XFER_UDMA_1,     0,   0,   0,   0,   0,   0, 0,    0,  80 },
3068 	{ XFER_UDMA_2,     0,   0,   0,   0,   0,   0, 0,    0,  60 },
3069 	{ XFER_UDMA_3,     0,   0,   0,   0,   0,   0, 0,    0,  45 },
3070 	{ XFER_UDMA_4,     0,   0,   0,   0,   0,   0, 0,    0,  30 },
3071 	{ XFER_UDMA_5,     0,   0,   0,   0,   0,   0, 0,    0,  20 },
3072 	{ XFER_UDMA_6,     0,   0,   0,   0,   0,   0, 0,    0,  15 },
3073 
3074 	{ 0xFF }
3075 };
3076 
3077 #define ENOUGH(v, unit)		(((v)-1)/(unit)+1)
3078 #define EZ(v, unit)		((v)?ENOUGH(v, unit):0)
3079 
3080 static void ata_timing_quantize(const struct ata_timing *t, struct ata_timing *q, int T, int UT)
3081 {
3082 	q->setup	= EZ(t->setup      * 1000,  T);
3083 	q->act8b	= EZ(t->act8b      * 1000,  T);
3084 	q->rec8b	= EZ(t->rec8b      * 1000,  T);
3085 	q->cyc8b	= EZ(t->cyc8b      * 1000,  T);
3086 	q->active	= EZ(t->active     * 1000,  T);
3087 	q->recover	= EZ(t->recover    * 1000,  T);
3088 	q->dmack_hold	= EZ(t->dmack_hold * 1000,  T);
3089 	q->cycle	= EZ(t->cycle      * 1000,  T);
3090 	q->udma		= EZ(t->udma       * 1000, UT);
3091 }
3092 
3093 void ata_timing_merge(const struct ata_timing *a, const struct ata_timing *b,
3094 		      struct ata_timing *m, unsigned int what)
3095 {
3096 	if (what & ATA_TIMING_SETUP  ) m->setup   = max(a->setup,   b->setup);
3097 	if (what & ATA_TIMING_ACT8B  ) m->act8b   = max(a->act8b,   b->act8b);
3098 	if (what & ATA_TIMING_REC8B  ) m->rec8b   = max(a->rec8b,   b->rec8b);
3099 	if (what & ATA_TIMING_CYC8B  ) m->cyc8b   = max(a->cyc8b,   b->cyc8b);
3100 	if (what & ATA_TIMING_ACTIVE ) m->active  = max(a->active,  b->active);
3101 	if (what & ATA_TIMING_RECOVER) m->recover = max(a->recover, b->recover);
3102 	if (what & ATA_TIMING_DMACK_HOLD) m->dmack_hold = max(a->dmack_hold, b->dmack_hold);
3103 	if (what & ATA_TIMING_CYCLE  ) m->cycle   = max(a->cycle,   b->cycle);
3104 	if (what & ATA_TIMING_UDMA   ) m->udma    = max(a->udma,    b->udma);
3105 }
3106 
3107 const struct ata_timing *ata_timing_find_mode(u8 xfer_mode)
3108 {
3109 	const struct ata_timing *t = ata_timing;
3110 
3111 	while (xfer_mode > t->mode)
3112 		t++;
3113 
3114 	if (xfer_mode == t->mode)
3115 		return t;
3116 	return NULL;
3117 }
3118 
3119 int ata_timing_compute(struct ata_device *adev, unsigned short speed,
3120 		       struct ata_timing *t, int T, int UT)
3121 {
3122 	const u16 *id = adev->id;
3123 	const struct ata_timing *s;
3124 	struct ata_timing p;
3125 
3126 	/*
3127 	 * Find the mode.
3128 	 */
3129 
3130 	if (!(s = ata_timing_find_mode(speed)))
3131 		return -EINVAL;
3132 
3133 	memcpy(t, s, sizeof(*s));
3134 
3135 	/*
3136 	 * If the drive is an EIDE drive, it can tell us it needs extended
3137 	 * PIO/MW_DMA cycle timing.
3138 	 */
3139 
3140 	if (id[ATA_ID_FIELD_VALID] & 2) {	/* EIDE drive */
3141 		memset(&p, 0, sizeof(p));
3142 
3143 		if (speed >= XFER_PIO_0 && speed <= XFER_SW_DMA_0) {
3144 			if (speed <= XFER_PIO_2)
3145 				p.cycle = p.cyc8b = id[ATA_ID_EIDE_PIO];
3146 			else if ((speed <= XFER_PIO_4) ||
3147 				 (speed == XFER_PIO_5 && !ata_id_is_cfa(id)))
3148 				p.cycle = p.cyc8b = id[ATA_ID_EIDE_PIO_IORDY];
3149 		} else if (speed >= XFER_MW_DMA_0 && speed <= XFER_MW_DMA_2)
3150 			p.cycle = id[ATA_ID_EIDE_DMA_MIN];
3151 
3152 		ata_timing_merge(&p, t, t, ATA_TIMING_CYCLE | ATA_TIMING_CYC8B);
3153 	}
3154 
3155 	/*
3156 	 * Convert the timing to bus clock counts.
3157 	 */
3158 
3159 	ata_timing_quantize(t, t, T, UT);
3160 
3161 	/*
3162 	 * Even in DMA/UDMA modes we still use PIO access for IDENTIFY,
3163 	 * S.M.A.R.T * and some other commands. We have to ensure that the
3164 	 * DMA cycle timing is slower/equal than the fastest PIO timing.
3165 	 */
3166 
3167 	if (speed > XFER_PIO_6) {
3168 		ata_timing_compute(adev, adev->pio_mode, &p, T, UT);
3169 		ata_timing_merge(&p, t, t, ATA_TIMING_ALL);
3170 	}
3171 
3172 	/*
3173 	 * Lengthen active & recovery time so that cycle time is correct.
3174 	 */
3175 
3176 	if (t->act8b + t->rec8b < t->cyc8b) {
3177 		t->act8b += (t->cyc8b - (t->act8b + t->rec8b)) / 2;
3178 		t->rec8b = t->cyc8b - t->act8b;
3179 	}
3180 
3181 	if (t->active + t->recover < t->cycle) {
3182 		t->active += (t->cycle - (t->active + t->recover)) / 2;
3183 		t->recover = t->cycle - t->active;
3184 	}
3185 
3186 	/* In a few cases quantisation may produce enough errors to
3187 	   leave t->cycle too low for the sum of active and recovery
3188 	   if so we must correct this */
3189 	if (t->active + t->recover > t->cycle)
3190 		t->cycle = t->active + t->recover;
3191 
3192 	return 0;
3193 }
3194 
3195 /**
3196  *	ata_timing_cycle2mode - find xfer mode for the specified cycle duration
3197  *	@xfer_shift: ATA_SHIFT_* value for transfer type to examine.
3198  *	@cycle: cycle duration in ns
3199  *
3200  *	Return matching xfer mode for @cycle.  The returned mode is of
3201  *	the transfer type specified by @xfer_shift.  If @cycle is too
3202  *	slow for @xfer_shift, 0xff is returned.  If @cycle is faster
3203  *	than the fastest known mode, the fasted mode is returned.
3204  *
3205  *	LOCKING:
3206  *	None.
3207  *
3208  *	RETURNS:
3209  *	Matching xfer_mode, 0xff if no match found.
3210  */
3211 u8 ata_timing_cycle2mode(unsigned int xfer_shift, int cycle)
3212 {
3213 	u8 base_mode = 0xff, last_mode = 0xff;
3214 	const struct ata_xfer_ent *ent;
3215 	const struct ata_timing *t;
3216 
3217 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
3218 		if (ent->shift == xfer_shift)
3219 			base_mode = ent->base;
3220 
3221 	for (t = ata_timing_find_mode(base_mode);
3222 	     t && ata_xfer_mode2shift(t->mode) == xfer_shift; t++) {
3223 		unsigned short this_cycle;
3224 
3225 		switch (xfer_shift) {
3226 		case ATA_SHIFT_PIO:
3227 		case ATA_SHIFT_MWDMA:
3228 			this_cycle = t->cycle;
3229 			break;
3230 		case ATA_SHIFT_UDMA:
3231 			this_cycle = t->udma;
3232 			break;
3233 		default:
3234 			return 0xff;
3235 		}
3236 
3237 		if (cycle > this_cycle)
3238 			break;
3239 
3240 		last_mode = t->mode;
3241 	}
3242 
3243 	return last_mode;
3244 }
3245 
3246 /**
3247  *	ata_down_xfermask_limit - adjust dev xfer masks downward
3248  *	@dev: Device to adjust xfer masks
3249  *	@sel: ATA_DNXFER_* selector
3250  *
3251  *	Adjust xfer masks of @dev downward.  Note that this function
3252  *	does not apply the change.  Invoking ata_set_mode() afterwards
3253  *	will apply the limit.
3254  *
3255  *	LOCKING:
3256  *	Inherited from caller.
3257  *
3258  *	RETURNS:
3259  *	0 on success, negative errno on failure
3260  */
3261 int ata_down_xfermask_limit(struct ata_device *dev, unsigned int sel)
3262 {
3263 	char buf[32];
3264 	unsigned long orig_mask, xfer_mask;
3265 	unsigned long pio_mask, mwdma_mask, udma_mask;
3266 	int quiet, highbit;
3267 
3268 	quiet = !!(sel & ATA_DNXFER_QUIET);
3269 	sel &= ~ATA_DNXFER_QUIET;
3270 
3271 	xfer_mask = orig_mask = ata_pack_xfermask(dev->pio_mask,
3272 						  dev->mwdma_mask,
3273 						  dev->udma_mask);
3274 	ata_unpack_xfermask(xfer_mask, &pio_mask, &mwdma_mask, &udma_mask);
3275 
3276 	switch (sel) {
3277 	case ATA_DNXFER_PIO:
3278 		highbit = fls(pio_mask) - 1;
3279 		pio_mask &= ~(1 << highbit);
3280 		break;
3281 
3282 	case ATA_DNXFER_DMA:
3283 		if (udma_mask) {
3284 			highbit = fls(udma_mask) - 1;
3285 			udma_mask &= ~(1 << highbit);
3286 			if (!udma_mask)
3287 				return -ENOENT;
3288 		} else if (mwdma_mask) {
3289 			highbit = fls(mwdma_mask) - 1;
3290 			mwdma_mask &= ~(1 << highbit);
3291 			if (!mwdma_mask)
3292 				return -ENOENT;
3293 		}
3294 		break;
3295 
3296 	case ATA_DNXFER_40C:
3297 		udma_mask &= ATA_UDMA_MASK_40C;
3298 		break;
3299 
3300 	case ATA_DNXFER_FORCE_PIO0:
3301 		pio_mask &= 1;
3302 	case ATA_DNXFER_FORCE_PIO:
3303 		mwdma_mask = 0;
3304 		udma_mask = 0;
3305 		break;
3306 
3307 	default:
3308 		BUG();
3309 	}
3310 
3311 	xfer_mask &= ata_pack_xfermask(pio_mask, mwdma_mask, udma_mask);
3312 
3313 	if (!(xfer_mask & ATA_MASK_PIO) || xfer_mask == orig_mask)
3314 		return -ENOENT;
3315 
3316 	if (!quiet) {
3317 		if (xfer_mask & (ATA_MASK_MWDMA | ATA_MASK_UDMA))
3318 			snprintf(buf, sizeof(buf), "%s:%s",
3319 				 ata_mode_string(xfer_mask),
3320 				 ata_mode_string(xfer_mask & ATA_MASK_PIO));
3321 		else
3322 			snprintf(buf, sizeof(buf), "%s",
3323 				 ata_mode_string(xfer_mask));
3324 
3325 		ata_dev_printk(dev, KERN_WARNING,
3326 			       "limiting speed to %s\n", buf);
3327 	}
3328 
3329 	ata_unpack_xfermask(xfer_mask, &dev->pio_mask, &dev->mwdma_mask,
3330 			    &dev->udma_mask);
3331 
3332 	return 0;
3333 }
3334 
3335 static int ata_dev_set_mode(struct ata_device *dev)
3336 {
3337 	struct ata_port *ap = dev->link->ap;
3338 	struct ata_eh_context *ehc = &dev->link->eh_context;
3339 	const bool nosetxfer = dev->horkage & ATA_HORKAGE_NOSETXFER;
3340 	const char *dev_err_whine = "";
3341 	int ign_dev_err = 0;
3342 	unsigned int err_mask = 0;
3343 	int rc;
3344 
3345 	dev->flags &= ~ATA_DFLAG_PIO;
3346 	if (dev->xfer_shift == ATA_SHIFT_PIO)
3347 		dev->flags |= ATA_DFLAG_PIO;
3348 
3349 	if (nosetxfer && ap->flags & ATA_FLAG_SATA && ata_id_is_sata(dev->id))
3350 		dev_err_whine = " (SET_XFERMODE skipped)";
3351 	else {
3352 		if (nosetxfer)
3353 			ata_dev_printk(dev, KERN_WARNING,
3354 				       "NOSETXFER but PATA detected - can't "
3355 				       "skip SETXFER, might malfunction\n");
3356 		err_mask = ata_dev_set_xfermode(dev);
3357 	}
3358 
3359 	if (err_mask & ~AC_ERR_DEV)
3360 		goto fail;
3361 
3362 	/* revalidate */
3363 	ehc->i.flags |= ATA_EHI_POST_SETMODE;
3364 	rc = ata_dev_revalidate(dev, ATA_DEV_UNKNOWN, 0);
3365 	ehc->i.flags &= ~ATA_EHI_POST_SETMODE;
3366 	if (rc)
3367 		return rc;
3368 
3369 	if (dev->xfer_shift == ATA_SHIFT_PIO) {
3370 		/* Old CFA may refuse this command, which is just fine */
3371 		if (ata_id_is_cfa(dev->id))
3372 			ign_dev_err = 1;
3373 		/* Catch several broken garbage emulations plus some pre
3374 		   ATA devices */
3375 		if (ata_id_major_version(dev->id) == 0 &&
3376 					dev->pio_mode <= XFER_PIO_2)
3377 			ign_dev_err = 1;
3378 		/* Some very old devices and some bad newer ones fail
3379 		   any kind of SET_XFERMODE request but support PIO0-2
3380 		   timings and no IORDY */
3381 		if (!ata_id_has_iordy(dev->id) && dev->pio_mode <= XFER_PIO_2)
3382 			ign_dev_err = 1;
3383 	}
3384 	/* Early MWDMA devices do DMA but don't allow DMA mode setting.
3385 	   Don't fail an MWDMA0 set IFF the device indicates it is in MWDMA0 */
3386 	if (dev->xfer_shift == ATA_SHIFT_MWDMA &&
3387 	    dev->dma_mode == XFER_MW_DMA_0 &&
3388 	    (dev->id[63] >> 8) & 1)
3389 		ign_dev_err = 1;
3390 
3391 	/* if the device is actually configured correctly, ignore dev err */
3392 	if (dev->xfer_mode == ata_xfer_mask2mode(ata_id_xfermask(dev->id)))
3393 		ign_dev_err = 1;
3394 
3395 	if (err_mask & AC_ERR_DEV) {
3396 		if (!ign_dev_err)
3397 			goto fail;
3398 		else
3399 			dev_err_whine = " (device error ignored)";
3400 	}
3401 
3402 	DPRINTK("xfer_shift=%u, xfer_mode=0x%x\n",
3403 		dev->xfer_shift, (int)dev->xfer_mode);
3404 
3405 	ata_dev_printk(dev, KERN_INFO, "configured for %s%s\n",
3406 		       ata_mode_string(ata_xfer_mode2mask(dev->xfer_mode)),
3407 		       dev_err_whine);
3408 
3409 	return 0;
3410 
3411  fail:
3412 	ata_dev_printk(dev, KERN_ERR, "failed to set xfermode "
3413 		       "(err_mask=0x%x)\n", err_mask);
3414 	return -EIO;
3415 }
3416 
3417 /**
3418  *	ata_do_set_mode - Program timings and issue SET FEATURES - XFER
3419  *	@link: link on which timings will be programmed
3420  *	@r_failed_dev: out parameter for failed device
3421  *
3422  *	Standard implementation of the function used to tune and set
3423  *	ATA device disk transfer mode (PIO3, UDMA6, etc.).  If
3424  *	ata_dev_set_mode() fails, pointer to the failing device is
3425  *	returned in @r_failed_dev.
3426  *
3427  *	LOCKING:
3428  *	PCI/etc. bus probe sem.
3429  *
3430  *	RETURNS:
3431  *	0 on success, negative errno otherwise
3432  */
3433 
3434 int ata_do_set_mode(struct ata_link *link, struct ata_device **r_failed_dev)
3435 {
3436 	struct ata_port *ap = link->ap;
3437 	struct ata_device *dev;
3438 	int rc = 0, used_dma = 0, found = 0;
3439 
3440 	/* step 1: calculate xfer_mask */
3441 	ata_for_each_dev(dev, link, ENABLED) {
3442 		unsigned long pio_mask, dma_mask;
3443 		unsigned int mode_mask;
3444 
3445 		mode_mask = ATA_DMA_MASK_ATA;
3446 		if (dev->class == ATA_DEV_ATAPI)
3447 			mode_mask = ATA_DMA_MASK_ATAPI;
3448 		else if (ata_id_is_cfa(dev->id))
3449 			mode_mask = ATA_DMA_MASK_CFA;
3450 
3451 		ata_dev_xfermask(dev);
3452 		ata_force_xfermask(dev);
3453 
3454 		pio_mask = ata_pack_xfermask(dev->pio_mask, 0, 0);
3455 		dma_mask = ata_pack_xfermask(0, dev->mwdma_mask, dev->udma_mask);
3456 
3457 		if (libata_dma_mask & mode_mask)
3458 			dma_mask = ata_pack_xfermask(0, dev->mwdma_mask, dev->udma_mask);
3459 		else
3460 			dma_mask = 0;
3461 
3462 		dev->pio_mode = ata_xfer_mask2mode(pio_mask);
3463 		dev->dma_mode = ata_xfer_mask2mode(dma_mask);
3464 
3465 		found = 1;
3466 		if (ata_dma_enabled(dev))
3467 			used_dma = 1;
3468 	}
3469 	if (!found)
3470 		goto out;
3471 
3472 	/* step 2: always set host PIO timings */
3473 	ata_for_each_dev(dev, link, ENABLED) {
3474 		if (dev->pio_mode == 0xff) {
3475 			ata_dev_printk(dev, KERN_WARNING, "no PIO support\n");
3476 			rc = -EINVAL;
3477 			goto out;
3478 		}
3479 
3480 		dev->xfer_mode = dev->pio_mode;
3481 		dev->xfer_shift = ATA_SHIFT_PIO;
3482 		if (ap->ops->set_piomode)
3483 			ap->ops->set_piomode(ap, dev);
3484 	}
3485 
3486 	/* step 3: set host DMA timings */
3487 	ata_for_each_dev(dev, link, ENABLED) {
3488 		if (!ata_dma_enabled(dev))
3489 			continue;
3490 
3491 		dev->xfer_mode = dev->dma_mode;
3492 		dev->xfer_shift = ata_xfer_mode2shift(dev->dma_mode);
3493 		if (ap->ops->set_dmamode)
3494 			ap->ops->set_dmamode(ap, dev);
3495 	}
3496 
3497 	/* step 4: update devices' xfer mode */
3498 	ata_for_each_dev(dev, link, ENABLED) {
3499 		rc = ata_dev_set_mode(dev);
3500 		if (rc)
3501 			goto out;
3502 	}
3503 
3504 	/* Record simplex status. If we selected DMA then the other
3505 	 * host channels are not permitted to do so.
3506 	 */
3507 	if (used_dma && (ap->host->flags & ATA_HOST_SIMPLEX))
3508 		ap->host->simplex_claimed = ap;
3509 
3510  out:
3511 	if (rc)
3512 		*r_failed_dev = dev;
3513 	return rc;
3514 }
3515 
3516 /**
3517  *	ata_wait_ready - wait for link to become ready
3518  *	@link: link to be waited on
3519  *	@deadline: deadline jiffies for the operation
3520  *	@check_ready: callback to check link readiness
3521  *
3522  *	Wait for @link to become ready.  @check_ready should return
3523  *	positive number if @link is ready, 0 if it isn't, -ENODEV if
3524  *	link doesn't seem to be occupied, other errno for other error
3525  *	conditions.
3526  *
3527  *	Transient -ENODEV conditions are allowed for
3528  *	ATA_TMOUT_FF_WAIT.
3529  *
3530  *	LOCKING:
3531  *	EH context.
3532  *
3533  *	RETURNS:
3534  *	0 if @linke is ready before @deadline; otherwise, -errno.
3535  */
3536 int ata_wait_ready(struct ata_link *link, unsigned long deadline,
3537 		   int (*check_ready)(struct ata_link *link))
3538 {
3539 	unsigned long start = jiffies;
3540 	unsigned long nodev_deadline;
3541 	int warned = 0;
3542 
3543 	/* choose which 0xff timeout to use, read comment in libata.h */
3544 	if (link->ap->host->flags & ATA_HOST_PARALLEL_SCAN)
3545 		nodev_deadline = ata_deadline(start, ATA_TMOUT_FF_WAIT_LONG);
3546 	else
3547 		nodev_deadline = ata_deadline(start, ATA_TMOUT_FF_WAIT);
3548 
3549 	/* Slave readiness can't be tested separately from master.  On
3550 	 * M/S emulation configuration, this function should be called
3551 	 * only on the master and it will handle both master and slave.
3552 	 */
3553 	WARN_ON(link == link->ap->slave_link);
3554 
3555 	if (time_after(nodev_deadline, deadline))
3556 		nodev_deadline = deadline;
3557 
3558 	while (1) {
3559 		unsigned long now = jiffies;
3560 		int ready, tmp;
3561 
3562 		ready = tmp = check_ready(link);
3563 		if (ready > 0)
3564 			return 0;
3565 
3566 		/*
3567 		 * -ENODEV could be transient.  Ignore -ENODEV if link
3568 		 * is online.  Also, some SATA devices take a long
3569 		 * time to clear 0xff after reset.  Wait for
3570 		 * ATA_TMOUT_FF_WAIT[_LONG] on -ENODEV if link isn't
3571 		 * offline.
3572 		 *
3573 		 * Note that some PATA controllers (pata_ali) explode
3574 		 * if status register is read more than once when
3575 		 * there's no device attached.
3576 		 */
3577 		if (ready == -ENODEV) {
3578 			if (ata_link_online(link))
3579 				ready = 0;
3580 			else if ((link->ap->flags & ATA_FLAG_SATA) &&
3581 				 !ata_link_offline(link) &&
3582 				 time_before(now, nodev_deadline))
3583 				ready = 0;
3584 		}
3585 
3586 		if (ready)
3587 			return ready;
3588 		if (time_after(now, deadline))
3589 			return -EBUSY;
3590 
3591 		if (!warned && time_after(now, start + 5 * HZ) &&
3592 		    (deadline - now > 3 * HZ)) {
3593 			ata_link_printk(link, KERN_WARNING,
3594 				"link is slow to respond, please be patient "
3595 				"(ready=%d)\n", tmp);
3596 			warned = 1;
3597 		}
3598 
3599 		msleep(50);
3600 	}
3601 }
3602 
3603 /**
3604  *	ata_wait_after_reset - wait for link to become ready after reset
3605  *	@link: link to be waited on
3606  *	@deadline: deadline jiffies for the operation
3607  *	@check_ready: callback to check link readiness
3608  *
3609  *	Wait for @link to become ready after reset.
3610  *
3611  *	LOCKING:
3612  *	EH context.
3613  *
3614  *	RETURNS:
3615  *	0 if @linke is ready before @deadline; otherwise, -errno.
3616  */
3617 int ata_wait_after_reset(struct ata_link *link, unsigned long deadline,
3618 				int (*check_ready)(struct ata_link *link))
3619 {
3620 	msleep(ATA_WAIT_AFTER_RESET);
3621 
3622 	return ata_wait_ready(link, deadline, check_ready);
3623 }
3624 
3625 /**
3626  *	sata_link_debounce - debounce SATA phy status
3627  *	@link: ATA link to debounce SATA phy status for
3628  *	@params: timing parameters { interval, duratinon, timeout } in msec
3629  *	@deadline: deadline jiffies for the operation
3630  *
3631 *	Make sure SStatus of @link reaches stable state, determined by
3632  *	holding the same value where DET is not 1 for @duration polled
3633  *	every @interval, before @timeout.  Timeout constraints the
3634  *	beginning of the stable state.  Because DET gets stuck at 1 on
3635  *	some controllers after hot unplugging, this functions waits
3636  *	until timeout then returns 0 if DET is stable at 1.
3637  *
3638  *	@timeout is further limited by @deadline.  The sooner of the
3639  *	two is used.
3640  *
3641  *	LOCKING:
3642  *	Kernel thread context (may sleep)
3643  *
3644  *	RETURNS:
3645  *	0 on success, -errno on failure.
3646  */
3647 int sata_link_debounce(struct ata_link *link, const unsigned long *params,
3648 		       unsigned long deadline)
3649 {
3650 	unsigned long interval = params[0];
3651 	unsigned long duration = params[1];
3652 	unsigned long last_jiffies, t;
3653 	u32 last, cur;
3654 	int rc;
3655 
3656 	t = ata_deadline(jiffies, params[2]);
3657 	if (time_before(t, deadline))
3658 		deadline = t;
3659 
3660 	if ((rc = sata_scr_read(link, SCR_STATUS, &cur)))
3661 		return rc;
3662 	cur &= 0xf;
3663 
3664 	last = cur;
3665 	last_jiffies = jiffies;
3666 
3667 	while (1) {
3668 		msleep(interval);
3669 		if ((rc = sata_scr_read(link, SCR_STATUS, &cur)))
3670 			return rc;
3671 		cur &= 0xf;
3672 
3673 		/* DET stable? */
3674 		if (cur == last) {
3675 			if (cur == 1 && time_before(jiffies, deadline))
3676 				continue;
3677 			if (time_after(jiffies,
3678 				       ata_deadline(last_jiffies, duration)))
3679 				return 0;
3680 			continue;
3681 		}
3682 
3683 		/* unstable, start over */
3684 		last = cur;
3685 		last_jiffies = jiffies;
3686 
3687 		/* Check deadline.  If debouncing failed, return
3688 		 * -EPIPE to tell upper layer to lower link speed.
3689 		 */
3690 		if (time_after(jiffies, deadline))
3691 			return -EPIPE;
3692 	}
3693 }
3694 
3695 /**
3696  *	sata_link_resume - resume SATA link
3697  *	@link: ATA link to resume SATA
3698  *	@params: timing parameters { interval, duratinon, timeout } in msec
3699  *	@deadline: deadline jiffies for the operation
3700  *
3701  *	Resume SATA phy @link and debounce it.
3702  *
3703  *	LOCKING:
3704  *	Kernel thread context (may sleep)
3705  *
3706  *	RETURNS:
3707  *	0 on success, -errno on failure.
3708  */
3709 int sata_link_resume(struct ata_link *link, const unsigned long *params,
3710 		     unsigned long deadline)
3711 {
3712 	int tries = ATA_LINK_RESUME_TRIES;
3713 	u32 scontrol, serror;
3714 	int rc;
3715 
3716 	if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3717 		return rc;
3718 
3719 	/*
3720 	 * Writes to SControl sometimes get ignored under certain
3721 	 * controllers (ata_piix SIDPR).  Make sure DET actually is
3722 	 * cleared.
3723 	 */
3724 	do {
3725 		scontrol = (scontrol & 0x0f0) | 0x300;
3726 		if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
3727 			return rc;
3728 		/*
3729 		 * Some PHYs react badly if SStatus is pounded
3730 		 * immediately after resuming.  Delay 200ms before
3731 		 * debouncing.
3732 		 */
3733 		msleep(200);
3734 
3735 		/* is SControl restored correctly? */
3736 		if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3737 			return rc;
3738 	} while ((scontrol & 0xf0f) != 0x300 && --tries);
3739 
3740 	if ((scontrol & 0xf0f) != 0x300) {
3741 		ata_link_printk(link, KERN_ERR,
3742 				"failed to resume link (SControl %X)\n",
3743 				scontrol);
3744 		return 0;
3745 	}
3746 
3747 	if (tries < ATA_LINK_RESUME_TRIES)
3748 		ata_link_printk(link, KERN_WARNING,
3749 				"link resume succeeded after %d retries\n",
3750 				ATA_LINK_RESUME_TRIES - tries);
3751 
3752 	if ((rc = sata_link_debounce(link, params, deadline)))
3753 		return rc;
3754 
3755 	/* clear SError, some PHYs require this even for SRST to work */
3756 	if (!(rc = sata_scr_read(link, SCR_ERROR, &serror)))
3757 		rc = sata_scr_write(link, SCR_ERROR, serror);
3758 
3759 	return rc != -EINVAL ? rc : 0;
3760 }
3761 
3762 /**
3763  *	ata_std_prereset - prepare for reset
3764  *	@link: ATA link to be reset
3765  *	@deadline: deadline jiffies for the operation
3766  *
3767  *	@link is about to be reset.  Initialize it.  Failure from
3768  *	prereset makes libata abort whole reset sequence and give up
3769  *	that port, so prereset should be best-effort.  It does its
3770  *	best to prepare for reset sequence but if things go wrong, it
3771  *	should just whine, not fail.
3772  *
3773  *	LOCKING:
3774  *	Kernel thread context (may sleep)
3775  *
3776  *	RETURNS:
3777  *	0 on success, -errno otherwise.
3778  */
3779 int ata_std_prereset(struct ata_link *link, unsigned long deadline)
3780 {
3781 	struct ata_port *ap = link->ap;
3782 	struct ata_eh_context *ehc = &link->eh_context;
3783 	const unsigned long *timing = sata_ehc_deb_timing(ehc);
3784 	int rc;
3785 
3786 	/* if we're about to do hardreset, nothing more to do */
3787 	if (ehc->i.action & ATA_EH_HARDRESET)
3788 		return 0;
3789 
3790 	/* if SATA, resume link */
3791 	if (ap->flags & ATA_FLAG_SATA) {
3792 		rc = sata_link_resume(link, timing, deadline);
3793 		/* whine about phy resume failure but proceed */
3794 		if (rc && rc != -EOPNOTSUPP)
3795 			ata_link_printk(link, KERN_WARNING, "failed to resume "
3796 					"link for reset (errno=%d)\n", rc);
3797 	}
3798 
3799 	/* no point in trying softreset on offline link */
3800 	if (ata_phys_link_offline(link))
3801 		ehc->i.action &= ~ATA_EH_SOFTRESET;
3802 
3803 	return 0;
3804 }
3805 
3806 /**
3807  *	sata_link_hardreset - reset link via SATA phy reset
3808  *	@link: link to reset
3809  *	@timing: timing parameters { interval, duratinon, timeout } in msec
3810  *	@deadline: deadline jiffies for the operation
3811  *	@online: optional out parameter indicating link onlineness
3812  *	@check_ready: optional callback to check link readiness
3813  *
3814  *	SATA phy-reset @link using DET bits of SControl register.
3815  *	After hardreset, link readiness is waited upon using
3816  *	ata_wait_ready() if @check_ready is specified.  LLDs are
3817  *	allowed to not specify @check_ready and wait itself after this
3818  *	function returns.  Device classification is LLD's
3819  *	responsibility.
3820  *
3821  *	*@online is set to one iff reset succeeded and @link is online
3822  *	after reset.
3823  *
3824  *	LOCKING:
3825  *	Kernel thread context (may sleep)
3826  *
3827  *	RETURNS:
3828  *	0 on success, -errno otherwise.
3829  */
3830 int sata_link_hardreset(struct ata_link *link, const unsigned long *timing,
3831 			unsigned long deadline,
3832 			bool *online, int (*check_ready)(struct ata_link *))
3833 {
3834 	u32 scontrol;
3835 	int rc;
3836 
3837 	DPRINTK("ENTER\n");
3838 
3839 	if (online)
3840 		*online = false;
3841 
3842 	if (sata_set_spd_needed(link)) {
3843 		/* SATA spec says nothing about how to reconfigure
3844 		 * spd.  To be on the safe side, turn off phy during
3845 		 * reconfiguration.  This works for at least ICH7 AHCI
3846 		 * and Sil3124.
3847 		 */
3848 		if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3849 			goto out;
3850 
3851 		scontrol = (scontrol & 0x0f0) | 0x304;
3852 
3853 		if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
3854 			goto out;
3855 
3856 		sata_set_spd(link);
3857 	}
3858 
3859 	/* issue phy wake/reset */
3860 	if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3861 		goto out;
3862 
3863 	scontrol = (scontrol & 0x0f0) | 0x301;
3864 
3865 	if ((rc = sata_scr_write_flush(link, SCR_CONTROL, scontrol)))
3866 		goto out;
3867 
3868 	/* Couldn't find anything in SATA I/II specs, but AHCI-1.1
3869 	 * 10.4.2 says at least 1 ms.
3870 	 */
3871 	msleep(1);
3872 
3873 	/* bring link back */
3874 	rc = sata_link_resume(link, timing, deadline);
3875 	if (rc)
3876 		goto out;
3877 	/* if link is offline nothing more to do */
3878 	if (ata_phys_link_offline(link))
3879 		goto out;
3880 
3881 	/* Link is online.  From this point, -ENODEV too is an error. */
3882 	if (online)
3883 		*online = true;
3884 
3885 	if (sata_pmp_supported(link->ap) && ata_is_host_link(link)) {
3886 		/* If PMP is supported, we have to do follow-up SRST.
3887 		 * Some PMPs don't send D2H Reg FIS after hardreset if
3888 		 * the first port is empty.  Wait only for
3889 		 * ATA_TMOUT_PMP_SRST_WAIT.
3890 		 */
3891 		if (check_ready) {
3892 			unsigned long pmp_deadline;
3893 
3894 			pmp_deadline = ata_deadline(jiffies,
3895 						    ATA_TMOUT_PMP_SRST_WAIT);
3896 			if (time_after(pmp_deadline, deadline))
3897 				pmp_deadline = deadline;
3898 			ata_wait_ready(link, pmp_deadline, check_ready);
3899 		}
3900 		rc = -EAGAIN;
3901 		goto out;
3902 	}
3903 
3904 	rc = 0;
3905 	if (check_ready)
3906 		rc = ata_wait_ready(link, deadline, check_ready);
3907  out:
3908 	if (rc && rc != -EAGAIN) {
3909 		/* online is set iff link is online && reset succeeded */
3910 		if (online)
3911 			*online = false;
3912 		ata_link_printk(link, KERN_ERR,
3913 				"COMRESET failed (errno=%d)\n", rc);
3914 	}
3915 	DPRINTK("EXIT, rc=%d\n", rc);
3916 	return rc;
3917 }
3918 
3919 /**
3920  *	sata_std_hardreset - COMRESET w/o waiting or classification
3921  *	@link: link to reset
3922  *	@class: resulting class of attached device
3923  *	@deadline: deadline jiffies for the operation
3924  *
3925  *	Standard SATA COMRESET w/o waiting or classification.
3926  *
3927  *	LOCKING:
3928  *	Kernel thread context (may sleep)
3929  *
3930  *	RETURNS:
3931  *	0 if link offline, -EAGAIN if link online, -errno on errors.
3932  */
3933 int sata_std_hardreset(struct ata_link *link, unsigned int *class,
3934 		       unsigned long deadline)
3935 {
3936 	const unsigned long *timing = sata_ehc_deb_timing(&link->eh_context);
3937 	bool online;
3938 	int rc;
3939 
3940 	/* do hardreset */
3941 	rc = sata_link_hardreset(link, timing, deadline, &online, NULL);
3942 	return online ? -EAGAIN : rc;
3943 }
3944 
3945 /**
3946  *	ata_std_postreset - standard postreset callback
3947  *	@link: the target ata_link
3948  *	@classes: classes of attached devices
3949  *
3950  *	This function is invoked after a successful reset.  Note that
3951  *	the device might have been reset more than once using
3952  *	different reset methods before postreset is invoked.
3953  *
3954  *	LOCKING:
3955  *	Kernel thread context (may sleep)
3956  */
3957 void ata_std_postreset(struct ata_link *link, unsigned int *classes)
3958 {
3959 	u32 serror;
3960 
3961 	DPRINTK("ENTER\n");
3962 
3963 	/* reset complete, clear SError */
3964 	if (!sata_scr_read(link, SCR_ERROR, &serror))
3965 		sata_scr_write(link, SCR_ERROR, serror);
3966 
3967 	/* print link status */
3968 	sata_print_link_status(link);
3969 
3970 	DPRINTK("EXIT\n");
3971 }
3972 
3973 /**
3974  *	ata_dev_same_device - Determine whether new ID matches configured device
3975  *	@dev: device to compare against
3976  *	@new_class: class of the new device
3977  *	@new_id: IDENTIFY page of the new device
3978  *
3979  *	Compare @new_class and @new_id against @dev and determine
3980  *	whether @dev is the device indicated by @new_class and
3981  *	@new_id.
3982  *
3983  *	LOCKING:
3984  *	None.
3985  *
3986  *	RETURNS:
3987  *	1 if @dev matches @new_class and @new_id, 0 otherwise.
3988  */
3989 static int ata_dev_same_device(struct ata_device *dev, unsigned int new_class,
3990 			       const u16 *new_id)
3991 {
3992 	const u16 *old_id = dev->id;
3993 	unsigned char model[2][ATA_ID_PROD_LEN + 1];
3994 	unsigned char serial[2][ATA_ID_SERNO_LEN + 1];
3995 
3996 	if (dev->class != new_class) {
3997 		ata_dev_printk(dev, KERN_INFO, "class mismatch %d != %d\n",
3998 			       dev->class, new_class);
3999 		return 0;
4000 	}
4001 
4002 	ata_id_c_string(old_id, model[0], ATA_ID_PROD, sizeof(model[0]));
4003 	ata_id_c_string(new_id, model[1], ATA_ID_PROD, sizeof(model[1]));
4004 	ata_id_c_string(old_id, serial[0], ATA_ID_SERNO, sizeof(serial[0]));
4005 	ata_id_c_string(new_id, serial[1], ATA_ID_SERNO, sizeof(serial[1]));
4006 
4007 	if (strcmp(model[0], model[1])) {
4008 		ata_dev_printk(dev, KERN_INFO, "model number mismatch "
4009 			       "'%s' != '%s'\n", model[0], model[1]);
4010 		return 0;
4011 	}
4012 
4013 	if (strcmp(serial[0], serial[1])) {
4014 		ata_dev_printk(dev, KERN_INFO, "serial number mismatch "
4015 			       "'%s' != '%s'\n", serial[0], serial[1]);
4016 		return 0;
4017 	}
4018 
4019 	return 1;
4020 }
4021 
4022 /**
4023  *	ata_dev_reread_id - Re-read IDENTIFY data
4024  *	@dev: target ATA device
4025  *	@readid_flags: read ID flags
4026  *
4027  *	Re-read IDENTIFY page and make sure @dev is still attached to
4028  *	the port.
4029  *
4030  *	LOCKING:
4031  *	Kernel thread context (may sleep)
4032  *
4033  *	RETURNS:
4034  *	0 on success, negative errno otherwise
4035  */
4036 int ata_dev_reread_id(struct ata_device *dev, unsigned int readid_flags)
4037 {
4038 	unsigned int class = dev->class;
4039 	u16 *id = (void *)dev->link->ap->sector_buf;
4040 	int rc;
4041 
4042 	/* read ID data */
4043 	rc = ata_dev_read_id(dev, &class, readid_flags, id);
4044 	if (rc)
4045 		return rc;
4046 
4047 	/* is the device still there? */
4048 	if (!ata_dev_same_device(dev, class, id))
4049 		return -ENODEV;
4050 
4051 	memcpy(dev->id, id, sizeof(id[0]) * ATA_ID_WORDS);
4052 	return 0;
4053 }
4054 
4055 /**
4056  *	ata_dev_revalidate - Revalidate ATA device
4057  *	@dev: device to revalidate
4058  *	@new_class: new class code
4059  *	@readid_flags: read ID flags
4060  *
4061  *	Re-read IDENTIFY page, make sure @dev is still attached to the
4062  *	port and reconfigure it according to the new IDENTIFY page.
4063  *
4064  *	LOCKING:
4065  *	Kernel thread context (may sleep)
4066  *
4067  *	RETURNS:
4068  *	0 on success, negative errno otherwise
4069  */
4070 int ata_dev_revalidate(struct ata_device *dev, unsigned int new_class,
4071 		       unsigned int readid_flags)
4072 {
4073 	u64 n_sectors = dev->n_sectors;
4074 	u64 n_native_sectors = dev->n_native_sectors;
4075 	int rc;
4076 
4077 	if (!ata_dev_enabled(dev))
4078 		return -ENODEV;
4079 
4080 	/* fail early if !ATA && !ATAPI to avoid issuing [P]IDENTIFY to PMP */
4081 	if (ata_class_enabled(new_class) &&
4082 	    new_class != ATA_DEV_ATA &&
4083 	    new_class != ATA_DEV_ATAPI &&
4084 	    new_class != ATA_DEV_SEMB) {
4085 		ata_dev_printk(dev, KERN_INFO, "class mismatch %u != %u\n",
4086 			       dev->class, new_class);
4087 		rc = -ENODEV;
4088 		goto fail;
4089 	}
4090 
4091 	/* re-read ID */
4092 	rc = ata_dev_reread_id(dev, readid_flags);
4093 	if (rc)
4094 		goto fail;
4095 
4096 	/* configure device according to the new ID */
4097 	rc = ata_dev_configure(dev);
4098 	if (rc)
4099 		goto fail;
4100 
4101 	/* verify n_sectors hasn't changed */
4102 	if (dev->class != ATA_DEV_ATA || !n_sectors ||
4103 	    dev->n_sectors == n_sectors)
4104 		return 0;
4105 
4106 	/* n_sectors has changed */
4107 	ata_dev_printk(dev, KERN_WARNING, "n_sectors mismatch %llu != %llu\n",
4108 		       (unsigned long long)n_sectors,
4109 		       (unsigned long long)dev->n_sectors);
4110 
4111 	/*
4112 	 * Something could have caused HPA to be unlocked
4113 	 * involuntarily.  If n_native_sectors hasn't changed and the
4114 	 * new size matches it, keep the device.
4115 	 */
4116 	if (dev->n_native_sectors == n_native_sectors &&
4117 	    dev->n_sectors > n_sectors && dev->n_sectors == n_native_sectors) {
4118 		ata_dev_printk(dev, KERN_WARNING,
4119 			       "new n_sectors matches native, probably "
4120 			       "late HPA unlock, n_sectors updated\n");
4121 		/* use the larger n_sectors */
4122 		return 0;
4123 	}
4124 
4125 	/*
4126 	 * Some BIOSes boot w/o HPA but resume w/ HPA locked.  Try
4127 	 * unlocking HPA in those cases.
4128 	 *
4129 	 * https://bugzilla.kernel.org/show_bug.cgi?id=15396
4130 	 */
4131 	if (dev->n_native_sectors == n_native_sectors &&
4132 	    dev->n_sectors < n_sectors && n_sectors == n_native_sectors &&
4133 	    !(dev->horkage & ATA_HORKAGE_BROKEN_HPA)) {
4134 		ata_dev_printk(dev, KERN_WARNING,
4135 			       "old n_sectors matches native, probably "
4136 			       "late HPA lock, will try to unlock HPA\n");
4137 		/* try unlocking HPA */
4138 		dev->flags |= ATA_DFLAG_UNLOCK_HPA;
4139 		rc = -EIO;
4140 	} else
4141 		rc = -ENODEV;
4142 
4143 	/* restore original n_[native_]sectors and fail */
4144 	dev->n_native_sectors = n_native_sectors;
4145 	dev->n_sectors = n_sectors;
4146  fail:
4147 	ata_dev_printk(dev, KERN_ERR, "revalidation failed (errno=%d)\n", rc);
4148 	return rc;
4149 }
4150 
4151 struct ata_blacklist_entry {
4152 	const char *model_num;
4153 	const char *model_rev;
4154 	unsigned long horkage;
4155 };
4156 
4157 static const struct ata_blacklist_entry ata_device_blacklist [] = {
4158 	/* Devices with DMA related problems under Linux */
4159 	{ "WDC AC11000H",	NULL,		ATA_HORKAGE_NODMA },
4160 	{ "WDC AC22100H",	NULL,		ATA_HORKAGE_NODMA },
4161 	{ "WDC AC32500H",	NULL,		ATA_HORKAGE_NODMA },
4162 	{ "WDC AC33100H",	NULL,		ATA_HORKAGE_NODMA },
4163 	{ "WDC AC31600H",	NULL,		ATA_HORKAGE_NODMA },
4164 	{ "WDC AC32100H",	"24.09P07",	ATA_HORKAGE_NODMA },
4165 	{ "WDC AC23200L",	"21.10N21",	ATA_HORKAGE_NODMA },
4166 	{ "Compaq CRD-8241B", 	NULL,		ATA_HORKAGE_NODMA },
4167 	{ "CRD-8400B",		NULL, 		ATA_HORKAGE_NODMA },
4168 	{ "CRD-848[02]B",	NULL,		ATA_HORKAGE_NODMA },
4169 	{ "CRD-84",		NULL,		ATA_HORKAGE_NODMA },
4170 	{ "SanDisk SDP3B",	NULL,		ATA_HORKAGE_NODMA },
4171 	{ "SanDisk SDP3B-64",	NULL,		ATA_HORKAGE_NODMA },
4172 	{ "SANYO CD-ROM CRD",	NULL,		ATA_HORKAGE_NODMA },
4173 	{ "HITACHI CDR-8",	NULL,		ATA_HORKAGE_NODMA },
4174 	{ "HITACHI CDR-8[34]35",NULL,		ATA_HORKAGE_NODMA },
4175 	{ "Toshiba CD-ROM XM-6202B", NULL,	ATA_HORKAGE_NODMA },
4176 	{ "TOSHIBA CD-ROM XM-1702BC", NULL,	ATA_HORKAGE_NODMA },
4177 	{ "CD-532E-A", 		NULL,		ATA_HORKAGE_NODMA },
4178 	{ "E-IDE CD-ROM CR-840",NULL,		ATA_HORKAGE_NODMA },
4179 	{ "CD-ROM Drive/F5A",	NULL,		ATA_HORKAGE_NODMA },
4180 	{ "WPI CDD-820", 	NULL,		ATA_HORKAGE_NODMA },
4181 	{ "SAMSUNG CD-ROM SC-148C", NULL,	ATA_HORKAGE_NODMA },
4182 	{ "SAMSUNG CD-ROM SC",	NULL,		ATA_HORKAGE_NODMA },
4183 	{ "ATAPI CD-ROM DRIVE 40X MAXIMUM",NULL,ATA_HORKAGE_NODMA },
4184 	{ "_NEC DV5800A", 	NULL,		ATA_HORKAGE_NODMA },
4185 	{ "SAMSUNG CD-ROM SN-124", "N001",	ATA_HORKAGE_NODMA },
4186 	{ "Seagate STT20000A", NULL,		ATA_HORKAGE_NODMA },
4187 	/* Odd clown on sil3726/4726 PMPs */
4188 	{ "Config  Disk",	NULL,		ATA_HORKAGE_DISABLE },
4189 
4190 	/* Weird ATAPI devices */
4191 	{ "TORiSAN DVD-ROM DRD-N216", NULL,	ATA_HORKAGE_MAX_SEC_128 },
4192 	{ "QUANTUM DAT    DAT72-000", NULL,	ATA_HORKAGE_ATAPI_MOD16_DMA },
4193 
4194 	/* Devices we expect to fail diagnostics */
4195 
4196 	/* Devices where NCQ should be avoided */
4197 	/* NCQ is slow */
4198 	{ "WDC WD740ADFD-00",	NULL,		ATA_HORKAGE_NONCQ },
4199 	{ "WDC WD740ADFD-00NLR1", NULL,		ATA_HORKAGE_NONCQ, },
4200 	/* http://thread.gmane.org/gmane.linux.ide/14907 */
4201 	{ "FUJITSU MHT2060BH",	NULL,		ATA_HORKAGE_NONCQ },
4202 	/* NCQ is broken */
4203 	{ "Maxtor *",		"BANC*",	ATA_HORKAGE_NONCQ },
4204 	{ "Maxtor 7V300F0",	"VA111630",	ATA_HORKAGE_NONCQ },
4205 	{ "ST380817AS",		"3.42",		ATA_HORKAGE_NONCQ },
4206 	{ "ST3160023AS",	"3.42",		ATA_HORKAGE_NONCQ },
4207 	{ "OCZ CORE_SSD",	"02.10104",	ATA_HORKAGE_NONCQ },
4208 
4209 	/* Seagate NCQ + FLUSH CACHE firmware bug */
4210 	{ "ST31500341AS",	"SD1[5-9]",	ATA_HORKAGE_NONCQ |
4211 						ATA_HORKAGE_FIRMWARE_WARN },
4212 
4213 	{ "ST31000333AS",	"SD1[5-9]",	ATA_HORKAGE_NONCQ |
4214 						ATA_HORKAGE_FIRMWARE_WARN },
4215 
4216 	{ "ST3640[36]23AS",	"SD1[5-9]",	ATA_HORKAGE_NONCQ |
4217 						ATA_HORKAGE_FIRMWARE_WARN },
4218 
4219 	{ "ST3320[68]13AS",	"SD1[5-9]",	ATA_HORKAGE_NONCQ |
4220 						ATA_HORKAGE_FIRMWARE_WARN },
4221 
4222 	/* Blacklist entries taken from Silicon Image 3124/3132
4223 	   Windows driver .inf file - also several Linux problem reports */
4224 	{ "HTS541060G9SA00",    "MB3OC60D",     ATA_HORKAGE_NONCQ, },
4225 	{ "HTS541080G9SA00",    "MB4OC60D",     ATA_HORKAGE_NONCQ, },
4226 	{ "HTS541010G9SA00",    "MBZOC60D",     ATA_HORKAGE_NONCQ, },
4227 
4228 	/* https://bugzilla.kernel.org/show_bug.cgi?id=15573 */
4229 	{ "C300-CTFDDAC128MAG",	"0001",		ATA_HORKAGE_NONCQ, },
4230 
4231 	/* devices which puke on READ_NATIVE_MAX */
4232 	{ "HDS724040KLSA80",	"KFAOA20N",	ATA_HORKAGE_BROKEN_HPA, },
4233 	{ "WDC WD3200JD-00KLB0", "WD-WCAMR1130137", ATA_HORKAGE_BROKEN_HPA },
4234 	{ "WDC WD2500JD-00HBB0", "WD-WMAL71490727", ATA_HORKAGE_BROKEN_HPA },
4235 	{ "MAXTOR 6L080L4",	"A93.0500",	ATA_HORKAGE_BROKEN_HPA },
4236 
4237 	/* this one allows HPA unlocking but fails IOs on the area */
4238 	{ "OCZ-VERTEX",		    "1.30",	ATA_HORKAGE_BROKEN_HPA },
4239 
4240 	/* Devices which report 1 sector over size HPA */
4241 	{ "ST340823A",		NULL,		ATA_HORKAGE_HPA_SIZE, },
4242 	{ "ST320413A",		NULL,		ATA_HORKAGE_HPA_SIZE, },
4243 	{ "ST310211A",		NULL,		ATA_HORKAGE_HPA_SIZE, },
4244 
4245 	/* Devices which get the IVB wrong */
4246 	{ "QUANTUM FIREBALLlct10 05", "A03.0900", ATA_HORKAGE_IVB, },
4247 	/* Maybe we should just blacklist TSSTcorp... */
4248 	{ "TSSTcorp CDDVDW SH-S202[HJN]", "SB0[01]",  ATA_HORKAGE_IVB, },
4249 
4250 	/* Devices that do not need bridging limits applied */
4251 	{ "MTRON MSP-SATA*",		NULL,	ATA_HORKAGE_BRIDGE_OK, },
4252 
4253 	/* Devices which aren't very happy with higher link speeds */
4254 	{ "WD My Book",			NULL,	ATA_HORKAGE_1_5_GBPS, },
4255 
4256 	/*
4257 	 * Devices which choke on SETXFER.  Applies only if both the
4258 	 * device and controller are SATA.
4259 	 */
4260 	{ "PIONEER DVD-RW  DVRTD08",	"1.00",	ATA_HORKAGE_NOSETXFER },
4261 
4262 	/* End Marker */
4263 	{ }
4264 };
4265 
4266 /**
4267  *	glob_match - match a text string against a glob-style pattern
4268  *	@text: the string to be examined
4269  *	@pattern: the glob-style pattern to be matched against
4270  *
4271  *	Either/both of text and pattern can be empty strings.
4272  *
4273  *	Match text against a glob-style pattern, with wildcards and simple sets:
4274  *
4275  *		?	matches any single character.
4276  *		*	matches any run of characters.
4277  *		[xyz]	matches a single character from the set: x, y, or z.
4278  *		[a-d]	matches a single character from the range: a, b, c, or d.
4279  *		[a-d0-9] matches a single character from either range.
4280  *
4281  *	The special characters ?, [, -, or *, can be matched using a set, eg. [*]
4282  *	Behaviour with malformed patterns is undefined, though generally reasonable.
4283  *
4284  *	Sample patterns:  "SD1?",  "SD1[0-5]",  "*R0",  "SD*1?[012]*xx"
4285  *
4286  *	This function uses one level of recursion per '*' in pattern.
4287  *	Since it calls _nothing_ else, and has _no_ explicit local variables,
4288  *	this will not cause stack problems for any reasonable use here.
4289  *
4290  *	RETURNS:
4291  *	0 on match, 1 otherwise.
4292  */
4293 static int glob_match (const char *text, const char *pattern)
4294 {
4295 	do {
4296 		/* Match single character or a '?' wildcard */
4297 		if (*text == *pattern || *pattern == '?') {
4298 			if (!*pattern++)
4299 				return 0;  /* End of both strings: match */
4300 		} else {
4301 			/* Match single char against a '[' bracketed ']' pattern set */
4302 			if (!*text || *pattern != '[')
4303 				break;  /* Not a pattern set */
4304 			while (*++pattern && *pattern != ']' && *text != *pattern) {
4305 				if (*pattern == '-' && *(pattern - 1) != '[')
4306 					if (*text > *(pattern - 1) && *text < *(pattern + 1)) {
4307 						++pattern;
4308 						break;
4309 					}
4310 			}
4311 			if (!*pattern || *pattern == ']')
4312 				return 1;  /* No match */
4313 			while (*pattern && *pattern++ != ']');
4314 		}
4315 	} while (*++text && *pattern);
4316 
4317 	/* Match any run of chars against a '*' wildcard */
4318 	if (*pattern == '*') {
4319 		if (!*++pattern)
4320 			return 0;  /* Match: avoid recursion at end of pattern */
4321 		/* Loop to handle additional pattern chars after the wildcard */
4322 		while (*text) {
4323 			if (glob_match(text, pattern) == 0)
4324 				return 0;  /* Remainder matched */
4325 			++text;  /* Absorb (match) this char and try again */
4326 		}
4327 	}
4328 	if (!*text && !*pattern)
4329 		return 0;  /* End of both strings: match */
4330 	return 1;  /* No match */
4331 }
4332 
4333 static unsigned long ata_dev_blacklisted(const struct ata_device *dev)
4334 {
4335 	unsigned char model_num[ATA_ID_PROD_LEN + 1];
4336 	unsigned char model_rev[ATA_ID_FW_REV_LEN + 1];
4337 	const struct ata_blacklist_entry *ad = ata_device_blacklist;
4338 
4339 	ata_id_c_string(dev->id, model_num, ATA_ID_PROD, sizeof(model_num));
4340 	ata_id_c_string(dev->id, model_rev, ATA_ID_FW_REV, sizeof(model_rev));
4341 
4342 	while (ad->model_num) {
4343 		if (!glob_match(model_num, ad->model_num)) {
4344 			if (ad->model_rev == NULL)
4345 				return ad->horkage;
4346 			if (!glob_match(model_rev, ad->model_rev))
4347 				return ad->horkage;
4348 		}
4349 		ad++;
4350 	}
4351 	return 0;
4352 }
4353 
4354 static int ata_dma_blacklisted(const struct ata_device *dev)
4355 {
4356 	/* We don't support polling DMA.
4357 	 * DMA blacklist those ATAPI devices with CDB-intr (and use PIO)
4358 	 * if the LLDD handles only interrupts in the HSM_ST_LAST state.
4359 	 */
4360 	if ((dev->link->ap->flags & ATA_FLAG_PIO_POLLING) &&
4361 	    (dev->flags & ATA_DFLAG_CDB_INTR))
4362 		return 1;
4363 	return (dev->horkage & ATA_HORKAGE_NODMA) ? 1 : 0;
4364 }
4365 
4366 /**
4367  *	ata_is_40wire		-	check drive side detection
4368  *	@dev: device
4369  *
4370  *	Perform drive side detection decoding, allowing for device vendors
4371  *	who can't follow the documentation.
4372  */
4373 
4374 static int ata_is_40wire(struct ata_device *dev)
4375 {
4376 	if (dev->horkage & ATA_HORKAGE_IVB)
4377 		return ata_drive_40wire_relaxed(dev->id);
4378 	return ata_drive_40wire(dev->id);
4379 }
4380 
4381 /**
4382  *	cable_is_40wire		-	40/80/SATA decider
4383  *	@ap: port to consider
4384  *
4385  *	This function encapsulates the policy for speed management
4386  *	in one place. At the moment we don't cache the result but
4387  *	there is a good case for setting ap->cbl to the result when
4388  *	we are called with unknown cables (and figuring out if it
4389  *	impacts hotplug at all).
4390  *
4391  *	Return 1 if the cable appears to be 40 wire.
4392  */
4393 
4394 static int cable_is_40wire(struct ata_port *ap)
4395 {
4396 	struct ata_link *link;
4397 	struct ata_device *dev;
4398 
4399 	/* If the controller thinks we are 40 wire, we are. */
4400 	if (ap->cbl == ATA_CBL_PATA40)
4401 		return 1;
4402 
4403 	/* If the controller thinks we are 80 wire, we are. */
4404 	if (ap->cbl == ATA_CBL_PATA80 || ap->cbl == ATA_CBL_SATA)
4405 		return 0;
4406 
4407 	/* If the system is known to be 40 wire short cable (eg
4408 	 * laptop), then we allow 80 wire modes even if the drive
4409 	 * isn't sure.
4410 	 */
4411 	if (ap->cbl == ATA_CBL_PATA40_SHORT)
4412 		return 0;
4413 
4414 	/* If the controller doesn't know, we scan.
4415 	 *
4416 	 * Note: We look for all 40 wire detects at this point.  Any
4417 	 *       80 wire detect is taken to be 80 wire cable because
4418 	 * - in many setups only the one drive (slave if present) will
4419 	 *   give a valid detect
4420 	 * - if you have a non detect capable drive you don't want it
4421 	 *   to colour the choice
4422 	 */
4423 	ata_for_each_link(link, ap, EDGE) {
4424 		ata_for_each_dev(dev, link, ENABLED) {
4425 			if (!ata_is_40wire(dev))
4426 				return 0;
4427 		}
4428 	}
4429 	return 1;
4430 }
4431 
4432 /**
4433  *	ata_dev_xfermask - Compute supported xfermask of the given device
4434  *	@dev: Device to compute xfermask for
4435  *
4436  *	Compute supported xfermask of @dev and store it in
4437  *	dev->*_mask.  This function is responsible for applying all
4438  *	known limits including host controller limits, device
4439  *	blacklist, etc...
4440  *
4441  *	LOCKING:
4442  *	None.
4443  */
4444 static void ata_dev_xfermask(struct ata_device *dev)
4445 {
4446 	struct ata_link *link = dev->link;
4447 	struct ata_port *ap = link->ap;
4448 	struct ata_host *host = ap->host;
4449 	unsigned long xfer_mask;
4450 
4451 	/* controller modes available */
4452 	xfer_mask = ata_pack_xfermask(ap->pio_mask,
4453 				      ap->mwdma_mask, ap->udma_mask);
4454 
4455 	/* drive modes available */
4456 	xfer_mask &= ata_pack_xfermask(dev->pio_mask,
4457 				       dev->mwdma_mask, dev->udma_mask);
4458 	xfer_mask &= ata_id_xfermask(dev->id);
4459 
4460 	/*
4461 	 *	CFA Advanced TrueIDE timings are not allowed on a shared
4462 	 *	cable
4463 	 */
4464 	if (ata_dev_pair(dev)) {
4465 		/* No PIO5 or PIO6 */
4466 		xfer_mask &= ~(0x03 << (ATA_SHIFT_PIO + 5));
4467 		/* No MWDMA3 or MWDMA 4 */
4468 		xfer_mask &= ~(0x03 << (ATA_SHIFT_MWDMA + 3));
4469 	}
4470 
4471 	if (ata_dma_blacklisted(dev)) {
4472 		xfer_mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA);
4473 		ata_dev_printk(dev, KERN_WARNING,
4474 			       "device is on DMA blacklist, disabling DMA\n");
4475 	}
4476 
4477 	if ((host->flags & ATA_HOST_SIMPLEX) &&
4478 	    host->simplex_claimed && host->simplex_claimed != ap) {
4479 		xfer_mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA);
4480 		ata_dev_printk(dev, KERN_WARNING, "simplex DMA is claimed by "
4481 			       "other device, disabling DMA\n");
4482 	}
4483 
4484 	if (ap->flags & ATA_FLAG_NO_IORDY)
4485 		xfer_mask &= ata_pio_mask_no_iordy(dev);
4486 
4487 	if (ap->ops->mode_filter)
4488 		xfer_mask = ap->ops->mode_filter(dev, xfer_mask);
4489 
4490 	/* Apply cable rule here.  Don't apply it early because when
4491 	 * we handle hot plug the cable type can itself change.
4492 	 * Check this last so that we know if the transfer rate was
4493 	 * solely limited by the cable.
4494 	 * Unknown or 80 wire cables reported host side are checked
4495 	 * drive side as well. Cases where we know a 40wire cable
4496 	 * is used safely for 80 are not checked here.
4497 	 */
4498 	if (xfer_mask & (0xF8 << ATA_SHIFT_UDMA))
4499 		/* UDMA/44 or higher would be available */
4500 		if (cable_is_40wire(ap)) {
4501 			ata_dev_printk(dev, KERN_WARNING,
4502 				 "limited to UDMA/33 due to 40-wire cable\n");
4503 			xfer_mask &= ~(0xF8 << ATA_SHIFT_UDMA);
4504 		}
4505 
4506 	ata_unpack_xfermask(xfer_mask, &dev->pio_mask,
4507 			    &dev->mwdma_mask, &dev->udma_mask);
4508 }
4509 
4510 /**
4511  *	ata_dev_set_xfermode - Issue SET FEATURES - XFER MODE command
4512  *	@dev: Device to which command will be sent
4513  *
4514  *	Issue SET FEATURES - XFER MODE command to device @dev
4515  *	on port @ap.
4516  *
4517  *	LOCKING:
4518  *	PCI/etc. bus probe sem.
4519  *
4520  *	RETURNS:
4521  *	0 on success, AC_ERR_* mask otherwise.
4522  */
4523 
4524 static unsigned int ata_dev_set_xfermode(struct ata_device *dev)
4525 {
4526 	struct ata_taskfile tf;
4527 	unsigned int err_mask;
4528 
4529 	/* set up set-features taskfile */
4530 	DPRINTK("set features - xfer mode\n");
4531 
4532 	/* Some controllers and ATAPI devices show flaky interrupt
4533 	 * behavior after setting xfer mode.  Use polling instead.
4534 	 */
4535 	ata_tf_init(dev, &tf);
4536 	tf.command = ATA_CMD_SET_FEATURES;
4537 	tf.feature = SETFEATURES_XFER;
4538 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE | ATA_TFLAG_POLLING;
4539 	tf.protocol = ATA_PROT_NODATA;
4540 	/* If we are using IORDY we must send the mode setting command */
4541 	if (ata_pio_need_iordy(dev))
4542 		tf.nsect = dev->xfer_mode;
4543 	/* If the device has IORDY and the controller does not - turn it off */
4544  	else if (ata_id_has_iordy(dev->id))
4545 		tf.nsect = 0x01;
4546 	else /* In the ancient relic department - skip all of this */
4547 		return 0;
4548 
4549 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
4550 
4551 	DPRINTK("EXIT, err_mask=%x\n", err_mask);
4552 	return err_mask;
4553 }
4554 /**
4555  *	ata_dev_set_feature - Issue SET FEATURES - SATA FEATURES
4556  *	@dev: Device to which command will be sent
4557  *	@enable: Whether to enable or disable the feature
4558  *	@feature: The sector count represents the feature to set
4559  *
4560  *	Issue SET FEATURES - SATA FEATURES command to device @dev
4561  *	on port @ap with sector count
4562  *
4563  *	LOCKING:
4564  *	PCI/etc. bus probe sem.
4565  *
4566  *	RETURNS:
4567  *	0 on success, AC_ERR_* mask otherwise.
4568  */
4569 static unsigned int ata_dev_set_feature(struct ata_device *dev, u8 enable,
4570 					u8 feature)
4571 {
4572 	struct ata_taskfile tf;
4573 	unsigned int err_mask;
4574 
4575 	/* set up set-features taskfile */
4576 	DPRINTK("set features - SATA features\n");
4577 
4578 	ata_tf_init(dev, &tf);
4579 	tf.command = ATA_CMD_SET_FEATURES;
4580 	tf.feature = enable;
4581 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
4582 	tf.protocol = ATA_PROT_NODATA;
4583 	tf.nsect = feature;
4584 
4585 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
4586 
4587 	DPRINTK("EXIT, err_mask=%x\n", err_mask);
4588 	return err_mask;
4589 }
4590 
4591 /**
4592  *	ata_dev_init_params - Issue INIT DEV PARAMS command
4593  *	@dev: Device to which command will be sent
4594  *	@heads: Number of heads (taskfile parameter)
4595  *	@sectors: Number of sectors (taskfile parameter)
4596  *
4597  *	LOCKING:
4598  *	Kernel thread context (may sleep)
4599  *
4600  *	RETURNS:
4601  *	0 on success, AC_ERR_* mask otherwise.
4602  */
4603 static unsigned int ata_dev_init_params(struct ata_device *dev,
4604 					u16 heads, u16 sectors)
4605 {
4606 	struct ata_taskfile tf;
4607 	unsigned int err_mask;
4608 
4609 	/* Number of sectors per track 1-255. Number of heads 1-16 */
4610 	if (sectors < 1 || sectors > 255 || heads < 1 || heads > 16)
4611 		return AC_ERR_INVALID;
4612 
4613 	/* set up init dev params taskfile */
4614 	DPRINTK("init dev params \n");
4615 
4616 	ata_tf_init(dev, &tf);
4617 	tf.command = ATA_CMD_INIT_DEV_PARAMS;
4618 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
4619 	tf.protocol = ATA_PROT_NODATA;
4620 	tf.nsect = sectors;
4621 	tf.device |= (heads - 1) & 0x0f; /* max head = num. of heads - 1 */
4622 
4623 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
4624 	/* A clean abort indicates an original or just out of spec drive
4625 	   and we should continue as we issue the setup based on the
4626 	   drive reported working geometry */
4627 	if (err_mask == AC_ERR_DEV && (tf.feature & ATA_ABORTED))
4628 		err_mask = 0;
4629 
4630 	DPRINTK("EXIT, err_mask=%x\n", err_mask);
4631 	return err_mask;
4632 }
4633 
4634 /**
4635  *	ata_sg_clean - Unmap DMA memory associated with command
4636  *	@qc: Command containing DMA memory to be released
4637  *
4638  *	Unmap all mapped DMA memory associated with this command.
4639  *
4640  *	LOCKING:
4641  *	spin_lock_irqsave(host lock)
4642  */
4643 void ata_sg_clean(struct ata_queued_cmd *qc)
4644 {
4645 	struct ata_port *ap = qc->ap;
4646 	struct scatterlist *sg = qc->sg;
4647 	int dir = qc->dma_dir;
4648 
4649 	WARN_ON_ONCE(sg == NULL);
4650 
4651 	VPRINTK("unmapping %u sg elements\n", qc->n_elem);
4652 
4653 	if (qc->n_elem)
4654 		dma_unmap_sg(ap->dev, sg, qc->orig_n_elem, dir);
4655 
4656 	qc->flags &= ~ATA_QCFLAG_DMAMAP;
4657 	qc->sg = NULL;
4658 }
4659 
4660 /**
4661  *	atapi_check_dma - Check whether ATAPI DMA can be supported
4662  *	@qc: Metadata associated with taskfile to check
4663  *
4664  *	Allow low-level driver to filter ATA PACKET commands, returning
4665  *	a status indicating whether or not it is OK to use DMA for the
4666  *	supplied PACKET command.
4667  *
4668  *	LOCKING:
4669  *	spin_lock_irqsave(host lock)
4670  *
4671  *	RETURNS: 0 when ATAPI DMA can be used
4672  *               nonzero otherwise
4673  */
4674 int atapi_check_dma(struct ata_queued_cmd *qc)
4675 {
4676 	struct ata_port *ap = qc->ap;
4677 
4678 	/* Don't allow DMA if it isn't multiple of 16 bytes.  Quite a
4679 	 * few ATAPI devices choke on such DMA requests.
4680 	 */
4681 	if (!(qc->dev->horkage & ATA_HORKAGE_ATAPI_MOD16_DMA) &&
4682 	    unlikely(qc->nbytes & 15))
4683 		return 1;
4684 
4685 	if (ap->ops->check_atapi_dma)
4686 		return ap->ops->check_atapi_dma(qc);
4687 
4688 	return 0;
4689 }
4690 
4691 /**
4692  *	ata_std_qc_defer - Check whether a qc needs to be deferred
4693  *	@qc: ATA command in question
4694  *
4695  *	Non-NCQ commands cannot run with any other command, NCQ or
4696  *	not.  As upper layer only knows the queue depth, we are
4697  *	responsible for maintaining exclusion.  This function checks
4698  *	whether a new command @qc can be issued.
4699  *
4700  *	LOCKING:
4701  *	spin_lock_irqsave(host lock)
4702  *
4703  *	RETURNS:
4704  *	ATA_DEFER_* if deferring is needed, 0 otherwise.
4705  */
4706 int ata_std_qc_defer(struct ata_queued_cmd *qc)
4707 {
4708 	struct ata_link *link = qc->dev->link;
4709 
4710 	if (qc->tf.protocol == ATA_PROT_NCQ) {
4711 		if (!ata_tag_valid(link->active_tag))
4712 			return 0;
4713 	} else {
4714 		if (!ata_tag_valid(link->active_tag) && !link->sactive)
4715 			return 0;
4716 	}
4717 
4718 	return ATA_DEFER_LINK;
4719 }
4720 
4721 void ata_noop_qc_prep(struct ata_queued_cmd *qc) { }
4722 
4723 /**
4724  *	ata_sg_init - Associate command with scatter-gather table.
4725  *	@qc: Command to be associated
4726  *	@sg: Scatter-gather table.
4727  *	@n_elem: Number of elements in s/g table.
4728  *
4729  *	Initialize the data-related elements of queued_cmd @qc
4730  *	to point to a scatter-gather table @sg, containing @n_elem
4731  *	elements.
4732  *
4733  *	LOCKING:
4734  *	spin_lock_irqsave(host lock)
4735  */
4736 void ata_sg_init(struct ata_queued_cmd *qc, struct scatterlist *sg,
4737 		 unsigned int n_elem)
4738 {
4739 	qc->sg = sg;
4740 	qc->n_elem = n_elem;
4741 	qc->cursg = qc->sg;
4742 }
4743 
4744 /**
4745  *	ata_sg_setup - DMA-map the scatter-gather table associated with a command.
4746  *	@qc: Command with scatter-gather table to be mapped.
4747  *
4748  *	DMA-map the scatter-gather table associated with queued_cmd @qc.
4749  *
4750  *	LOCKING:
4751  *	spin_lock_irqsave(host lock)
4752  *
4753  *	RETURNS:
4754  *	Zero on success, negative on error.
4755  *
4756  */
4757 static int ata_sg_setup(struct ata_queued_cmd *qc)
4758 {
4759 	struct ata_port *ap = qc->ap;
4760 	unsigned int n_elem;
4761 
4762 	VPRINTK("ENTER, ata%u\n", ap->print_id);
4763 
4764 	n_elem = dma_map_sg(ap->dev, qc->sg, qc->n_elem, qc->dma_dir);
4765 	if (n_elem < 1)
4766 		return -1;
4767 
4768 	DPRINTK("%d sg elements mapped\n", n_elem);
4769 	qc->orig_n_elem = qc->n_elem;
4770 	qc->n_elem = n_elem;
4771 	qc->flags |= ATA_QCFLAG_DMAMAP;
4772 
4773 	return 0;
4774 }
4775 
4776 /**
4777  *	swap_buf_le16 - swap halves of 16-bit words in place
4778  *	@buf:  Buffer to swap
4779  *	@buf_words:  Number of 16-bit words in buffer.
4780  *
4781  *	Swap halves of 16-bit words if needed to convert from
4782  *	little-endian byte order to native cpu byte order, or
4783  *	vice-versa.
4784  *
4785  *	LOCKING:
4786  *	Inherited from caller.
4787  */
4788 void swap_buf_le16(u16 *buf, unsigned int buf_words)
4789 {
4790 #ifdef __BIG_ENDIAN
4791 	unsigned int i;
4792 
4793 	for (i = 0; i < buf_words; i++)
4794 		buf[i] = le16_to_cpu(buf[i]);
4795 #endif /* __BIG_ENDIAN */
4796 }
4797 
4798 /**
4799  *	ata_qc_new - Request an available ATA command, for queueing
4800  *	@ap: target port
4801  *
4802  *	LOCKING:
4803  *	None.
4804  */
4805 
4806 static struct ata_queued_cmd *ata_qc_new(struct ata_port *ap)
4807 {
4808 	struct ata_queued_cmd *qc = NULL;
4809 	unsigned int i;
4810 
4811 	/* no command while frozen */
4812 	if (unlikely(ap->pflags & ATA_PFLAG_FROZEN))
4813 		return NULL;
4814 
4815 	/* the last tag is reserved for internal command. */
4816 	for (i = 0; i < ATA_MAX_QUEUE - 1; i++)
4817 		if (!test_and_set_bit(i, &ap->qc_allocated)) {
4818 			qc = __ata_qc_from_tag(ap, i);
4819 			break;
4820 		}
4821 
4822 	if (qc)
4823 		qc->tag = i;
4824 
4825 	return qc;
4826 }
4827 
4828 /**
4829  *	ata_qc_new_init - Request an available ATA command, and initialize it
4830  *	@dev: Device from whom we request an available command structure
4831  *
4832  *	LOCKING:
4833  *	None.
4834  */
4835 
4836 struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev)
4837 {
4838 	struct ata_port *ap = dev->link->ap;
4839 	struct ata_queued_cmd *qc;
4840 
4841 	qc = ata_qc_new(ap);
4842 	if (qc) {
4843 		qc->scsicmd = NULL;
4844 		qc->ap = ap;
4845 		qc->dev = dev;
4846 
4847 		ata_qc_reinit(qc);
4848 	}
4849 
4850 	return qc;
4851 }
4852 
4853 /**
4854  *	ata_qc_free - free unused ata_queued_cmd
4855  *	@qc: Command to complete
4856  *
4857  *	Designed to free unused ata_queued_cmd object
4858  *	in case something prevents using it.
4859  *
4860  *	LOCKING:
4861  *	spin_lock_irqsave(host lock)
4862  */
4863 void ata_qc_free(struct ata_queued_cmd *qc)
4864 {
4865 	struct ata_port *ap;
4866 	unsigned int tag;
4867 
4868 	WARN_ON_ONCE(qc == NULL); /* ata_qc_from_tag _might_ return NULL */
4869 	ap = qc->ap;
4870 
4871 	qc->flags = 0;
4872 	tag = qc->tag;
4873 	if (likely(ata_tag_valid(tag))) {
4874 		qc->tag = ATA_TAG_POISON;
4875 		clear_bit(tag, &ap->qc_allocated);
4876 	}
4877 }
4878 
4879 void __ata_qc_complete(struct ata_queued_cmd *qc)
4880 {
4881 	struct ata_port *ap;
4882 	struct ata_link *link;
4883 
4884 	WARN_ON_ONCE(qc == NULL); /* ata_qc_from_tag _might_ return NULL */
4885 	WARN_ON_ONCE(!(qc->flags & ATA_QCFLAG_ACTIVE));
4886 	ap = qc->ap;
4887 	link = qc->dev->link;
4888 
4889 	if (likely(qc->flags & ATA_QCFLAG_DMAMAP))
4890 		ata_sg_clean(qc);
4891 
4892 	/* command should be marked inactive atomically with qc completion */
4893 	if (qc->tf.protocol == ATA_PROT_NCQ) {
4894 		link->sactive &= ~(1 << qc->tag);
4895 		if (!link->sactive)
4896 			ap->nr_active_links--;
4897 	} else {
4898 		link->active_tag = ATA_TAG_POISON;
4899 		ap->nr_active_links--;
4900 	}
4901 
4902 	/* clear exclusive status */
4903 	if (unlikely(qc->flags & ATA_QCFLAG_CLEAR_EXCL &&
4904 		     ap->excl_link == link))
4905 		ap->excl_link = NULL;
4906 
4907 	/* atapi: mark qc as inactive to prevent the interrupt handler
4908 	 * from completing the command twice later, before the error handler
4909 	 * is called. (when rc != 0 and atapi request sense is needed)
4910 	 */
4911 	qc->flags &= ~ATA_QCFLAG_ACTIVE;
4912 	ap->qc_active &= ~(1 << qc->tag);
4913 
4914 	/* call completion callback */
4915 	qc->complete_fn(qc);
4916 }
4917 
4918 static void fill_result_tf(struct ata_queued_cmd *qc)
4919 {
4920 	struct ata_port *ap = qc->ap;
4921 
4922 	qc->result_tf.flags = qc->tf.flags;
4923 	ap->ops->qc_fill_rtf(qc);
4924 }
4925 
4926 static void ata_verify_xfer(struct ata_queued_cmd *qc)
4927 {
4928 	struct ata_device *dev = qc->dev;
4929 
4930 	if (ata_tag_internal(qc->tag))
4931 		return;
4932 
4933 	if (ata_is_nodata(qc->tf.protocol))
4934 		return;
4935 
4936 	if ((dev->mwdma_mask || dev->udma_mask) && ata_is_pio(qc->tf.protocol))
4937 		return;
4938 
4939 	dev->flags &= ~ATA_DFLAG_DUBIOUS_XFER;
4940 }
4941 
4942 /**
4943  *	ata_qc_complete - Complete an active ATA command
4944  *	@qc: Command to complete
4945  *
4946  *	Indicate to the mid and upper layers that an ATA
4947  *	command has completed, with either an ok or not-ok status.
4948  *
4949  *	LOCKING:
4950  *	spin_lock_irqsave(host lock)
4951  */
4952 void ata_qc_complete(struct ata_queued_cmd *qc)
4953 {
4954 	struct ata_port *ap = qc->ap;
4955 
4956 	/* XXX: New EH and old EH use different mechanisms to
4957 	 * synchronize EH with regular execution path.
4958 	 *
4959 	 * In new EH, a failed qc is marked with ATA_QCFLAG_FAILED.
4960 	 * Normal execution path is responsible for not accessing a
4961 	 * failed qc.  libata core enforces the rule by returning NULL
4962 	 * from ata_qc_from_tag() for failed qcs.
4963 	 *
4964 	 * Old EH depends on ata_qc_complete() nullifying completion
4965 	 * requests if ATA_QCFLAG_EH_SCHEDULED is set.  Old EH does
4966 	 * not synchronize with interrupt handler.  Only PIO task is
4967 	 * taken care of.
4968 	 */
4969 	if (ap->ops->error_handler) {
4970 		struct ata_device *dev = qc->dev;
4971 		struct ata_eh_info *ehi = &dev->link->eh_info;
4972 
4973 		if (unlikely(qc->err_mask))
4974 			qc->flags |= ATA_QCFLAG_FAILED;
4975 
4976 		if (unlikely(qc->flags & ATA_QCFLAG_FAILED)) {
4977 			/* always fill result TF for failed qc */
4978 			fill_result_tf(qc);
4979 
4980 			if (!ata_tag_internal(qc->tag))
4981 				ata_qc_schedule_eh(qc);
4982 			else
4983 				__ata_qc_complete(qc);
4984 			return;
4985 		}
4986 
4987 		WARN_ON_ONCE(ap->pflags & ATA_PFLAG_FROZEN);
4988 
4989 		/* read result TF if requested */
4990 		if (qc->flags & ATA_QCFLAG_RESULT_TF)
4991 			fill_result_tf(qc);
4992 
4993 		/* Some commands need post-processing after successful
4994 		 * completion.
4995 		 */
4996 		switch (qc->tf.command) {
4997 		case ATA_CMD_SET_FEATURES:
4998 			if (qc->tf.feature != SETFEATURES_WC_ON &&
4999 			    qc->tf.feature != SETFEATURES_WC_OFF)
5000 				break;
5001 			/* fall through */
5002 		case ATA_CMD_INIT_DEV_PARAMS: /* CHS translation changed */
5003 		case ATA_CMD_SET_MULTI: /* multi_count changed */
5004 			/* revalidate device */
5005 			ehi->dev_action[dev->devno] |= ATA_EH_REVALIDATE;
5006 			ata_port_schedule_eh(ap);
5007 			break;
5008 
5009 		case ATA_CMD_SLEEP:
5010 			dev->flags |= ATA_DFLAG_SLEEPING;
5011 			break;
5012 		}
5013 
5014 		if (unlikely(dev->flags & ATA_DFLAG_DUBIOUS_XFER))
5015 			ata_verify_xfer(qc);
5016 
5017 		__ata_qc_complete(qc);
5018 	} else {
5019 		if (qc->flags & ATA_QCFLAG_EH_SCHEDULED)
5020 			return;
5021 
5022 		/* read result TF if failed or requested */
5023 		if (qc->err_mask || qc->flags & ATA_QCFLAG_RESULT_TF)
5024 			fill_result_tf(qc);
5025 
5026 		__ata_qc_complete(qc);
5027 	}
5028 }
5029 
5030 /**
5031  *	ata_qc_complete_multiple - Complete multiple qcs successfully
5032  *	@ap: port in question
5033  *	@qc_active: new qc_active mask
5034  *
5035  *	Complete in-flight commands.  This functions is meant to be
5036  *	called from low-level driver's interrupt routine to complete
5037  *	requests normally.  ap->qc_active and @qc_active is compared
5038  *	and commands are completed accordingly.
5039  *
5040  *	LOCKING:
5041  *	spin_lock_irqsave(host lock)
5042  *
5043  *	RETURNS:
5044  *	Number of completed commands on success, -errno otherwise.
5045  */
5046 int ata_qc_complete_multiple(struct ata_port *ap, u32 qc_active)
5047 {
5048 	int nr_done = 0;
5049 	u32 done_mask;
5050 
5051 	done_mask = ap->qc_active ^ qc_active;
5052 
5053 	if (unlikely(done_mask & qc_active)) {
5054 		ata_port_printk(ap, KERN_ERR, "illegal qc_active transition "
5055 				"(%08x->%08x)\n", ap->qc_active, qc_active);
5056 		return -EINVAL;
5057 	}
5058 
5059 	while (done_mask) {
5060 		struct ata_queued_cmd *qc;
5061 		unsigned int tag = __ffs(done_mask);
5062 
5063 		qc = ata_qc_from_tag(ap, tag);
5064 		if (qc) {
5065 			ata_qc_complete(qc);
5066 			nr_done++;
5067 		}
5068 		done_mask &= ~(1 << tag);
5069 	}
5070 
5071 	return nr_done;
5072 }
5073 
5074 /**
5075  *	ata_qc_issue - issue taskfile to device
5076  *	@qc: command to issue to device
5077  *
5078  *	Prepare an ATA command to submission to device.
5079  *	This includes mapping the data into a DMA-able
5080  *	area, filling in the S/G table, and finally
5081  *	writing the taskfile to hardware, starting the command.
5082  *
5083  *	LOCKING:
5084  *	spin_lock_irqsave(host lock)
5085  */
5086 void ata_qc_issue(struct ata_queued_cmd *qc)
5087 {
5088 	struct ata_port *ap = qc->ap;
5089 	struct ata_link *link = qc->dev->link;
5090 	u8 prot = qc->tf.protocol;
5091 
5092 	/* Make sure only one non-NCQ command is outstanding.  The
5093 	 * check is skipped for old EH because it reuses active qc to
5094 	 * request ATAPI sense.
5095 	 */
5096 	WARN_ON_ONCE(ap->ops->error_handler && ata_tag_valid(link->active_tag));
5097 
5098 	if (ata_is_ncq(prot)) {
5099 		WARN_ON_ONCE(link->sactive & (1 << qc->tag));
5100 
5101 		if (!link->sactive)
5102 			ap->nr_active_links++;
5103 		link->sactive |= 1 << qc->tag;
5104 	} else {
5105 		WARN_ON_ONCE(link->sactive);
5106 
5107 		ap->nr_active_links++;
5108 		link->active_tag = qc->tag;
5109 	}
5110 
5111 	qc->flags |= ATA_QCFLAG_ACTIVE;
5112 	ap->qc_active |= 1 << qc->tag;
5113 
5114 	/* We guarantee to LLDs that they will have at least one
5115 	 * non-zero sg if the command is a data command.
5116 	 */
5117 	BUG_ON(ata_is_data(prot) && (!qc->sg || !qc->n_elem || !qc->nbytes));
5118 
5119 	if (ata_is_dma(prot) || (ata_is_pio(prot) &&
5120 				 (ap->flags & ATA_FLAG_PIO_DMA)))
5121 		if (ata_sg_setup(qc))
5122 			goto sg_err;
5123 
5124 	/* if device is sleeping, schedule reset and abort the link */
5125 	if (unlikely(qc->dev->flags & ATA_DFLAG_SLEEPING)) {
5126 		link->eh_info.action |= ATA_EH_RESET;
5127 		ata_ehi_push_desc(&link->eh_info, "waking up from sleep");
5128 		ata_link_abort(link);
5129 		return;
5130 	}
5131 
5132 	ap->ops->qc_prep(qc);
5133 
5134 	qc->err_mask |= ap->ops->qc_issue(qc);
5135 	if (unlikely(qc->err_mask))
5136 		goto err;
5137 	return;
5138 
5139 sg_err:
5140 	qc->err_mask |= AC_ERR_SYSTEM;
5141 err:
5142 	ata_qc_complete(qc);
5143 }
5144 
5145 /**
5146  *	sata_scr_valid - test whether SCRs are accessible
5147  *	@link: ATA link to test SCR accessibility for
5148  *
5149  *	Test whether SCRs are accessible for @link.
5150  *
5151  *	LOCKING:
5152  *	None.
5153  *
5154  *	RETURNS:
5155  *	1 if SCRs are accessible, 0 otherwise.
5156  */
5157 int sata_scr_valid(struct ata_link *link)
5158 {
5159 	struct ata_port *ap = link->ap;
5160 
5161 	return (ap->flags & ATA_FLAG_SATA) && ap->ops->scr_read;
5162 }
5163 
5164 /**
5165  *	sata_scr_read - read SCR register of the specified port
5166  *	@link: ATA link to read SCR for
5167  *	@reg: SCR to read
5168  *	@val: Place to store read value
5169  *
5170  *	Read SCR register @reg of @link into *@val.  This function is
5171  *	guaranteed to succeed if @link is ap->link, the cable type of
5172  *	the port is SATA and the port implements ->scr_read.
5173  *
5174  *	LOCKING:
5175  *	None if @link is ap->link.  Kernel thread context otherwise.
5176  *
5177  *	RETURNS:
5178  *	0 on success, negative errno on failure.
5179  */
5180 int sata_scr_read(struct ata_link *link, int reg, u32 *val)
5181 {
5182 	if (ata_is_host_link(link)) {
5183 		if (sata_scr_valid(link))
5184 			return link->ap->ops->scr_read(link, reg, val);
5185 		return -EOPNOTSUPP;
5186 	}
5187 
5188 	return sata_pmp_scr_read(link, reg, val);
5189 }
5190 
5191 /**
5192  *	sata_scr_write - write SCR register of the specified port
5193  *	@link: ATA link to write SCR for
5194  *	@reg: SCR to write
5195  *	@val: value to write
5196  *
5197  *	Write @val to SCR register @reg of @link.  This function is
5198  *	guaranteed to succeed if @link is ap->link, the cable type of
5199  *	the port is SATA and the port implements ->scr_read.
5200  *
5201  *	LOCKING:
5202  *	None if @link is ap->link.  Kernel thread context otherwise.
5203  *
5204  *	RETURNS:
5205  *	0 on success, negative errno on failure.
5206  */
5207 int sata_scr_write(struct ata_link *link, int reg, u32 val)
5208 {
5209 	if (ata_is_host_link(link)) {
5210 		if (sata_scr_valid(link))
5211 			return link->ap->ops->scr_write(link, reg, val);
5212 		return -EOPNOTSUPP;
5213 	}
5214 
5215 	return sata_pmp_scr_write(link, reg, val);
5216 }
5217 
5218 /**
5219  *	sata_scr_write_flush - write SCR register of the specified port and flush
5220  *	@link: ATA link to write SCR for
5221  *	@reg: SCR to write
5222  *	@val: value to write
5223  *
5224  *	This function is identical to sata_scr_write() except that this
5225  *	function performs flush after writing to the register.
5226  *
5227  *	LOCKING:
5228  *	None if @link is ap->link.  Kernel thread context otherwise.
5229  *
5230  *	RETURNS:
5231  *	0 on success, negative errno on failure.
5232  */
5233 int sata_scr_write_flush(struct ata_link *link, int reg, u32 val)
5234 {
5235 	if (ata_is_host_link(link)) {
5236 		int rc;
5237 
5238 		if (sata_scr_valid(link)) {
5239 			rc = link->ap->ops->scr_write(link, reg, val);
5240 			if (rc == 0)
5241 				rc = link->ap->ops->scr_read(link, reg, &val);
5242 			return rc;
5243 		}
5244 		return -EOPNOTSUPP;
5245 	}
5246 
5247 	return sata_pmp_scr_write(link, reg, val);
5248 }
5249 
5250 /**
5251  *	ata_phys_link_online - test whether the given link is online
5252  *	@link: ATA link to test
5253  *
5254  *	Test whether @link is online.  Note that this function returns
5255  *	0 if online status of @link cannot be obtained, so
5256  *	ata_link_online(link) != !ata_link_offline(link).
5257  *
5258  *	LOCKING:
5259  *	None.
5260  *
5261  *	RETURNS:
5262  *	True if the port online status is available and online.
5263  */
5264 bool ata_phys_link_online(struct ata_link *link)
5265 {
5266 	u32 sstatus;
5267 
5268 	if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0 &&
5269 	    ata_sstatus_online(sstatus))
5270 		return true;
5271 	return false;
5272 }
5273 
5274 /**
5275  *	ata_phys_link_offline - test whether the given link is offline
5276  *	@link: ATA link to test
5277  *
5278  *	Test whether @link is offline.  Note that this function
5279  *	returns 0 if offline status of @link cannot be obtained, so
5280  *	ata_link_online(link) != !ata_link_offline(link).
5281  *
5282  *	LOCKING:
5283  *	None.
5284  *
5285  *	RETURNS:
5286  *	True if the port offline status is available and offline.
5287  */
5288 bool ata_phys_link_offline(struct ata_link *link)
5289 {
5290 	u32 sstatus;
5291 
5292 	if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0 &&
5293 	    !ata_sstatus_online(sstatus))
5294 		return true;
5295 	return false;
5296 }
5297 
5298 /**
5299  *	ata_link_online - test whether the given link is online
5300  *	@link: ATA link to test
5301  *
5302  *	Test whether @link is online.  This is identical to
5303  *	ata_phys_link_online() when there's no slave link.  When
5304  *	there's a slave link, this function should only be called on
5305  *	the master link and will return true if any of M/S links is
5306  *	online.
5307  *
5308  *	LOCKING:
5309  *	None.
5310  *
5311  *	RETURNS:
5312  *	True if the port online status is available and online.
5313  */
5314 bool ata_link_online(struct ata_link *link)
5315 {
5316 	struct ata_link *slave = link->ap->slave_link;
5317 
5318 	WARN_ON(link == slave);	/* shouldn't be called on slave link */
5319 
5320 	return ata_phys_link_online(link) ||
5321 		(slave && ata_phys_link_online(slave));
5322 }
5323 
5324 /**
5325  *	ata_link_offline - test whether the given link is offline
5326  *	@link: ATA link to test
5327  *
5328  *	Test whether @link is offline.  This is identical to
5329  *	ata_phys_link_offline() when there's no slave link.  When
5330  *	there's a slave link, this function should only be called on
5331  *	the master link and will return true if both M/S links are
5332  *	offline.
5333  *
5334  *	LOCKING:
5335  *	None.
5336  *
5337  *	RETURNS:
5338  *	True if the port offline status is available and offline.
5339  */
5340 bool ata_link_offline(struct ata_link *link)
5341 {
5342 	struct ata_link *slave = link->ap->slave_link;
5343 
5344 	WARN_ON(link == slave);	/* shouldn't be called on slave link */
5345 
5346 	return ata_phys_link_offline(link) &&
5347 		(!slave || ata_phys_link_offline(slave));
5348 }
5349 
5350 #ifdef CONFIG_PM
5351 static int ata_host_request_pm(struct ata_host *host, pm_message_t mesg,
5352 			       unsigned int action, unsigned int ehi_flags,
5353 			       int wait)
5354 {
5355 	unsigned long flags;
5356 	int i, rc;
5357 
5358 	for (i = 0; i < host->n_ports; i++) {
5359 		struct ata_port *ap = host->ports[i];
5360 		struct ata_link *link;
5361 
5362 		/* Previous resume operation might still be in
5363 		 * progress.  Wait for PM_PENDING to clear.
5364 		 */
5365 		if (ap->pflags & ATA_PFLAG_PM_PENDING) {
5366 			ata_port_wait_eh(ap);
5367 			WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
5368 		}
5369 
5370 		/* request PM ops to EH */
5371 		spin_lock_irqsave(ap->lock, flags);
5372 
5373 		ap->pm_mesg = mesg;
5374 		if (wait) {
5375 			rc = 0;
5376 			ap->pm_result = &rc;
5377 		}
5378 
5379 		ap->pflags |= ATA_PFLAG_PM_PENDING;
5380 		ata_for_each_link(link, ap, HOST_FIRST) {
5381 			link->eh_info.action |= action;
5382 			link->eh_info.flags |= ehi_flags;
5383 		}
5384 
5385 		ata_port_schedule_eh(ap);
5386 
5387 		spin_unlock_irqrestore(ap->lock, flags);
5388 
5389 		/* wait and check result */
5390 		if (wait) {
5391 			ata_port_wait_eh(ap);
5392 			WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
5393 			if (rc)
5394 				return rc;
5395 		}
5396 	}
5397 
5398 	return 0;
5399 }
5400 
5401 /**
5402  *	ata_host_suspend - suspend host
5403  *	@host: host to suspend
5404  *	@mesg: PM message
5405  *
5406  *	Suspend @host.  Actual operation is performed by EH.  This
5407  *	function requests EH to perform PM operations and waits for EH
5408  *	to finish.
5409  *
5410  *	LOCKING:
5411  *	Kernel thread context (may sleep).
5412  *
5413  *	RETURNS:
5414  *	0 on success, -errno on failure.
5415  */
5416 int ata_host_suspend(struct ata_host *host, pm_message_t mesg)
5417 {
5418 	int rc;
5419 
5420 	/*
5421 	 * disable link pm on all ports before requesting
5422 	 * any pm activity
5423 	 */
5424 	ata_lpm_enable(host);
5425 
5426 	rc = ata_host_request_pm(host, mesg, 0, ATA_EHI_QUIET, 1);
5427 	if (rc == 0)
5428 		host->dev->power.power_state = mesg;
5429 	return rc;
5430 }
5431 
5432 /**
5433  *	ata_host_resume - resume host
5434  *	@host: host to resume
5435  *
5436  *	Resume @host.  Actual operation is performed by EH.  This
5437  *	function requests EH to perform PM operations and returns.
5438  *	Note that all resume operations are performed parallely.
5439  *
5440  *	LOCKING:
5441  *	Kernel thread context (may sleep).
5442  */
5443 void ata_host_resume(struct ata_host *host)
5444 {
5445 	ata_host_request_pm(host, PMSG_ON, ATA_EH_RESET,
5446 			    ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET, 0);
5447 	host->dev->power.power_state = PMSG_ON;
5448 
5449 	/* reenable link pm */
5450 	ata_lpm_disable(host);
5451 }
5452 #endif
5453 
5454 /**
5455  *	ata_dev_init - Initialize an ata_device structure
5456  *	@dev: Device structure to initialize
5457  *
5458  *	Initialize @dev in preparation for probing.
5459  *
5460  *	LOCKING:
5461  *	Inherited from caller.
5462  */
5463 void ata_dev_init(struct ata_device *dev)
5464 {
5465 	struct ata_link *link = ata_dev_phys_link(dev);
5466 	struct ata_port *ap = link->ap;
5467 	unsigned long flags;
5468 
5469 	/* SATA spd limit is bound to the attached device, reset together */
5470 	link->sata_spd_limit = link->hw_sata_spd_limit;
5471 	link->sata_spd = 0;
5472 
5473 	/* High bits of dev->flags are used to record warm plug
5474 	 * requests which occur asynchronously.  Synchronize using
5475 	 * host lock.
5476 	 */
5477 	spin_lock_irqsave(ap->lock, flags);
5478 	dev->flags &= ~ATA_DFLAG_INIT_MASK;
5479 	dev->horkage = 0;
5480 	spin_unlock_irqrestore(ap->lock, flags);
5481 
5482 	memset((void *)dev + ATA_DEVICE_CLEAR_BEGIN, 0,
5483 	       ATA_DEVICE_CLEAR_END - ATA_DEVICE_CLEAR_BEGIN);
5484 	dev->pio_mask = UINT_MAX;
5485 	dev->mwdma_mask = UINT_MAX;
5486 	dev->udma_mask = UINT_MAX;
5487 }
5488 
5489 /**
5490  *	ata_link_init - Initialize an ata_link structure
5491  *	@ap: ATA port link is attached to
5492  *	@link: Link structure to initialize
5493  *	@pmp: Port multiplier port number
5494  *
5495  *	Initialize @link.
5496  *
5497  *	LOCKING:
5498  *	Kernel thread context (may sleep)
5499  */
5500 void ata_link_init(struct ata_port *ap, struct ata_link *link, int pmp)
5501 {
5502 	int i;
5503 
5504 	/* clear everything except for devices */
5505 	memset(link, 0, offsetof(struct ata_link, device[0]));
5506 
5507 	link->ap = ap;
5508 	link->pmp = pmp;
5509 	link->active_tag = ATA_TAG_POISON;
5510 	link->hw_sata_spd_limit = UINT_MAX;
5511 
5512 	/* can't use iterator, ap isn't initialized yet */
5513 	for (i = 0; i < ATA_MAX_DEVICES; i++) {
5514 		struct ata_device *dev = &link->device[i];
5515 
5516 		dev->link = link;
5517 		dev->devno = dev - link->device;
5518 #ifdef CONFIG_ATA_ACPI
5519 		dev->gtf_filter = ata_acpi_gtf_filter;
5520 #endif
5521 		ata_dev_init(dev);
5522 	}
5523 }
5524 
5525 /**
5526  *	sata_link_init_spd - Initialize link->sata_spd_limit
5527  *	@link: Link to configure sata_spd_limit for
5528  *
5529  *	Initialize @link->[hw_]sata_spd_limit to the currently
5530  *	configured value.
5531  *
5532  *	LOCKING:
5533  *	Kernel thread context (may sleep).
5534  *
5535  *	RETURNS:
5536  *	0 on success, -errno on failure.
5537  */
5538 int sata_link_init_spd(struct ata_link *link)
5539 {
5540 	u8 spd;
5541 	int rc;
5542 
5543 	rc = sata_scr_read(link, SCR_CONTROL, &link->saved_scontrol);
5544 	if (rc)
5545 		return rc;
5546 
5547 	spd = (link->saved_scontrol >> 4) & 0xf;
5548 	if (spd)
5549 		link->hw_sata_spd_limit &= (1 << spd) - 1;
5550 
5551 	ata_force_link_limits(link);
5552 
5553 	link->sata_spd_limit = link->hw_sata_spd_limit;
5554 
5555 	return 0;
5556 }
5557 
5558 /**
5559  *	ata_port_alloc - allocate and initialize basic ATA port resources
5560  *	@host: ATA host this allocated port belongs to
5561  *
5562  *	Allocate and initialize basic ATA port resources.
5563  *
5564  *	RETURNS:
5565  *	Allocate ATA port on success, NULL on failure.
5566  *
5567  *	LOCKING:
5568  *	Inherited from calling layer (may sleep).
5569  */
5570 struct ata_port *ata_port_alloc(struct ata_host *host)
5571 {
5572 	struct ata_port *ap;
5573 
5574 	DPRINTK("ENTER\n");
5575 
5576 	ap = kzalloc(sizeof(*ap), GFP_KERNEL);
5577 	if (!ap)
5578 		return NULL;
5579 
5580 	ap->pflags |= ATA_PFLAG_INITIALIZING;
5581 	ap->lock = &host->lock;
5582 	ap->print_id = -1;
5583 	ap->host = host;
5584 	ap->dev = host->dev;
5585 
5586 #if defined(ATA_VERBOSE_DEBUG)
5587 	/* turn on all debugging levels */
5588 	ap->msg_enable = 0x00FF;
5589 #elif defined(ATA_DEBUG)
5590 	ap->msg_enable = ATA_MSG_DRV | ATA_MSG_INFO | ATA_MSG_CTL | ATA_MSG_WARN | ATA_MSG_ERR;
5591 #else
5592 	ap->msg_enable = ATA_MSG_DRV | ATA_MSG_ERR | ATA_MSG_WARN;
5593 #endif
5594 
5595 	mutex_init(&ap->scsi_scan_mutex);
5596 	INIT_DELAYED_WORK(&ap->hotplug_task, ata_scsi_hotplug);
5597 	INIT_WORK(&ap->scsi_rescan_task, ata_scsi_dev_rescan);
5598 	INIT_LIST_HEAD(&ap->eh_done_q);
5599 	init_waitqueue_head(&ap->eh_wait_q);
5600 	init_completion(&ap->park_req_pending);
5601 	init_timer_deferrable(&ap->fastdrain_timer);
5602 	ap->fastdrain_timer.function = ata_eh_fastdrain_timerfn;
5603 	ap->fastdrain_timer.data = (unsigned long)ap;
5604 
5605 	ap->cbl = ATA_CBL_NONE;
5606 
5607 	ata_link_init(ap, &ap->link, 0);
5608 
5609 #ifdef ATA_IRQ_TRAP
5610 	ap->stats.unhandled_irq = 1;
5611 	ap->stats.idle_irq = 1;
5612 #endif
5613 	ata_sff_port_init(ap);
5614 
5615 	return ap;
5616 }
5617 
5618 static void ata_host_release(struct device *gendev, void *res)
5619 {
5620 	struct ata_host *host = dev_get_drvdata(gendev);
5621 	int i;
5622 
5623 	for (i = 0; i < host->n_ports; i++) {
5624 		struct ata_port *ap = host->ports[i];
5625 
5626 		if (!ap)
5627 			continue;
5628 
5629 		if (ap->scsi_host)
5630 			scsi_host_put(ap->scsi_host);
5631 
5632 		kfree(ap->pmp_link);
5633 		kfree(ap->slave_link);
5634 		kfree(ap);
5635 		host->ports[i] = NULL;
5636 	}
5637 
5638 	dev_set_drvdata(gendev, NULL);
5639 }
5640 
5641 /**
5642  *	ata_host_alloc - allocate and init basic ATA host resources
5643  *	@dev: generic device this host is associated with
5644  *	@max_ports: maximum number of ATA ports associated with this host
5645  *
5646  *	Allocate and initialize basic ATA host resources.  LLD calls
5647  *	this function to allocate a host, initializes it fully and
5648  *	attaches it using ata_host_register().
5649  *
5650  *	@max_ports ports are allocated and host->n_ports is
5651  *	initialized to @max_ports.  The caller is allowed to decrease
5652  *	host->n_ports before calling ata_host_register().  The unused
5653  *	ports will be automatically freed on registration.
5654  *
5655  *	RETURNS:
5656  *	Allocate ATA host on success, NULL on failure.
5657  *
5658  *	LOCKING:
5659  *	Inherited from calling layer (may sleep).
5660  */
5661 struct ata_host *ata_host_alloc(struct device *dev, int max_ports)
5662 {
5663 	struct ata_host *host;
5664 	size_t sz;
5665 	int i;
5666 
5667 	DPRINTK("ENTER\n");
5668 
5669 	if (!devres_open_group(dev, NULL, GFP_KERNEL))
5670 		return NULL;
5671 
5672 	/* alloc a container for our list of ATA ports (buses) */
5673 	sz = sizeof(struct ata_host) + (max_ports + 1) * sizeof(void *);
5674 	/* alloc a container for our list of ATA ports (buses) */
5675 	host = devres_alloc(ata_host_release, sz, GFP_KERNEL);
5676 	if (!host)
5677 		goto err_out;
5678 
5679 	devres_add(dev, host);
5680 	dev_set_drvdata(dev, host);
5681 
5682 	spin_lock_init(&host->lock);
5683 	host->dev = dev;
5684 	host->n_ports = max_ports;
5685 
5686 	/* allocate ports bound to this host */
5687 	for (i = 0; i < max_ports; i++) {
5688 		struct ata_port *ap;
5689 
5690 		ap = ata_port_alloc(host);
5691 		if (!ap)
5692 			goto err_out;
5693 
5694 		ap->port_no = i;
5695 		host->ports[i] = ap;
5696 	}
5697 
5698 	devres_remove_group(dev, NULL);
5699 	return host;
5700 
5701  err_out:
5702 	devres_release_group(dev, NULL);
5703 	return NULL;
5704 }
5705 
5706 /**
5707  *	ata_host_alloc_pinfo - alloc host and init with port_info array
5708  *	@dev: generic device this host is associated with
5709  *	@ppi: array of ATA port_info to initialize host with
5710  *	@n_ports: number of ATA ports attached to this host
5711  *
5712  *	Allocate ATA host and initialize with info from @ppi.  If NULL
5713  *	terminated, @ppi may contain fewer entries than @n_ports.  The
5714  *	last entry will be used for the remaining ports.
5715  *
5716  *	RETURNS:
5717  *	Allocate ATA host on success, NULL on failure.
5718  *
5719  *	LOCKING:
5720  *	Inherited from calling layer (may sleep).
5721  */
5722 struct ata_host *ata_host_alloc_pinfo(struct device *dev,
5723 				      const struct ata_port_info * const * ppi,
5724 				      int n_ports)
5725 {
5726 	const struct ata_port_info *pi;
5727 	struct ata_host *host;
5728 	int i, j;
5729 
5730 	host = ata_host_alloc(dev, n_ports);
5731 	if (!host)
5732 		return NULL;
5733 
5734 	for (i = 0, j = 0, pi = NULL; i < host->n_ports; i++) {
5735 		struct ata_port *ap = host->ports[i];
5736 
5737 		if (ppi[j])
5738 			pi = ppi[j++];
5739 
5740 		ap->pio_mask = pi->pio_mask;
5741 		ap->mwdma_mask = pi->mwdma_mask;
5742 		ap->udma_mask = pi->udma_mask;
5743 		ap->flags |= pi->flags;
5744 		ap->link.flags |= pi->link_flags;
5745 		ap->ops = pi->port_ops;
5746 
5747 		if (!host->ops && (pi->port_ops != &ata_dummy_port_ops))
5748 			host->ops = pi->port_ops;
5749 	}
5750 
5751 	return host;
5752 }
5753 
5754 /**
5755  *	ata_slave_link_init - initialize slave link
5756  *	@ap: port to initialize slave link for
5757  *
5758  *	Create and initialize slave link for @ap.  This enables slave
5759  *	link handling on the port.
5760  *
5761  *	In libata, a port contains links and a link contains devices.
5762  *	There is single host link but if a PMP is attached to it,
5763  *	there can be multiple fan-out links.  On SATA, there's usually
5764  *	a single device connected to a link but PATA and SATA
5765  *	controllers emulating TF based interface can have two - master
5766  *	and slave.
5767  *
5768  *	However, there are a few controllers which don't fit into this
5769  *	abstraction too well - SATA controllers which emulate TF
5770  *	interface with both master and slave devices but also have
5771  *	separate SCR register sets for each device.  These controllers
5772  *	need separate links for physical link handling
5773  *	(e.g. onlineness, link speed) but should be treated like a
5774  *	traditional M/S controller for everything else (e.g. command
5775  *	issue, softreset).
5776  *
5777  *	slave_link is libata's way of handling this class of
5778  *	controllers without impacting core layer too much.  For
5779  *	anything other than physical link handling, the default host
5780  *	link is used for both master and slave.  For physical link
5781  *	handling, separate @ap->slave_link is used.  All dirty details
5782  *	are implemented inside libata core layer.  From LLD's POV, the
5783  *	only difference is that prereset, hardreset and postreset are
5784  *	called once more for the slave link, so the reset sequence
5785  *	looks like the following.
5786  *
5787  *	prereset(M) -> prereset(S) -> hardreset(M) -> hardreset(S) ->
5788  *	softreset(M) -> postreset(M) -> postreset(S)
5789  *
5790  *	Note that softreset is called only for the master.  Softreset
5791  *	resets both M/S by definition, so SRST on master should handle
5792  *	both (the standard method will work just fine).
5793  *
5794  *	LOCKING:
5795  *	Should be called before host is registered.
5796  *
5797  *	RETURNS:
5798  *	0 on success, -errno on failure.
5799  */
5800 int ata_slave_link_init(struct ata_port *ap)
5801 {
5802 	struct ata_link *link;
5803 
5804 	WARN_ON(ap->slave_link);
5805 	WARN_ON(ap->flags & ATA_FLAG_PMP);
5806 
5807 	link = kzalloc(sizeof(*link), GFP_KERNEL);
5808 	if (!link)
5809 		return -ENOMEM;
5810 
5811 	ata_link_init(ap, link, 1);
5812 	ap->slave_link = link;
5813 	return 0;
5814 }
5815 
5816 static void ata_host_stop(struct device *gendev, void *res)
5817 {
5818 	struct ata_host *host = dev_get_drvdata(gendev);
5819 	int i;
5820 
5821 	WARN_ON(!(host->flags & ATA_HOST_STARTED));
5822 
5823 	for (i = 0; i < host->n_ports; i++) {
5824 		struct ata_port *ap = host->ports[i];
5825 
5826 		if (ap->ops->port_stop)
5827 			ap->ops->port_stop(ap);
5828 	}
5829 
5830 	if (host->ops->host_stop)
5831 		host->ops->host_stop(host);
5832 }
5833 
5834 /**
5835  *	ata_finalize_port_ops - finalize ata_port_operations
5836  *	@ops: ata_port_operations to finalize
5837  *
5838  *	An ata_port_operations can inherit from another ops and that
5839  *	ops can again inherit from another.  This can go on as many
5840  *	times as necessary as long as there is no loop in the
5841  *	inheritance chain.
5842  *
5843  *	Ops tables are finalized when the host is started.  NULL or
5844  *	unspecified entries are inherited from the closet ancestor
5845  *	which has the method and the entry is populated with it.
5846  *	After finalization, the ops table directly points to all the
5847  *	methods and ->inherits is no longer necessary and cleared.
5848  *
5849  *	Using ATA_OP_NULL, inheriting ops can force a method to NULL.
5850  *
5851  *	LOCKING:
5852  *	None.
5853  */
5854 static void ata_finalize_port_ops(struct ata_port_operations *ops)
5855 {
5856 	static DEFINE_SPINLOCK(lock);
5857 	const struct ata_port_operations *cur;
5858 	void **begin = (void **)ops;
5859 	void **end = (void **)&ops->inherits;
5860 	void **pp;
5861 
5862 	if (!ops || !ops->inherits)
5863 		return;
5864 
5865 	spin_lock(&lock);
5866 
5867 	for (cur = ops->inherits; cur; cur = cur->inherits) {
5868 		void **inherit = (void **)cur;
5869 
5870 		for (pp = begin; pp < end; pp++, inherit++)
5871 			if (!*pp)
5872 				*pp = *inherit;
5873 	}
5874 
5875 	for (pp = begin; pp < end; pp++)
5876 		if (IS_ERR(*pp))
5877 			*pp = NULL;
5878 
5879 	ops->inherits = NULL;
5880 
5881 	spin_unlock(&lock);
5882 }
5883 
5884 /**
5885  *	ata_host_start - start and freeze ports of an ATA host
5886  *	@host: ATA host to start ports for
5887  *
5888  *	Start and then freeze ports of @host.  Started status is
5889  *	recorded in host->flags, so this function can be called
5890  *	multiple times.  Ports are guaranteed to get started only
5891  *	once.  If host->ops isn't initialized yet, its set to the
5892  *	first non-dummy port ops.
5893  *
5894  *	LOCKING:
5895  *	Inherited from calling layer (may sleep).
5896  *
5897  *	RETURNS:
5898  *	0 if all ports are started successfully, -errno otherwise.
5899  */
5900 int ata_host_start(struct ata_host *host)
5901 {
5902 	int have_stop = 0;
5903 	void *start_dr = NULL;
5904 	int i, rc;
5905 
5906 	if (host->flags & ATA_HOST_STARTED)
5907 		return 0;
5908 
5909 	ata_finalize_port_ops(host->ops);
5910 
5911 	for (i = 0; i < host->n_ports; i++) {
5912 		struct ata_port *ap = host->ports[i];
5913 
5914 		ata_finalize_port_ops(ap->ops);
5915 
5916 		if (!host->ops && !ata_port_is_dummy(ap))
5917 			host->ops = ap->ops;
5918 
5919 		if (ap->ops->port_stop)
5920 			have_stop = 1;
5921 	}
5922 
5923 	if (host->ops->host_stop)
5924 		have_stop = 1;
5925 
5926 	if (have_stop) {
5927 		start_dr = devres_alloc(ata_host_stop, 0, GFP_KERNEL);
5928 		if (!start_dr)
5929 			return -ENOMEM;
5930 	}
5931 
5932 	for (i = 0; i < host->n_ports; i++) {
5933 		struct ata_port *ap = host->ports[i];
5934 
5935 		if (ap->ops->port_start) {
5936 			rc = ap->ops->port_start(ap);
5937 			if (rc) {
5938 				if (rc != -ENODEV)
5939 					dev_printk(KERN_ERR, host->dev,
5940 						"failed to start port %d "
5941 						"(errno=%d)\n", i, rc);
5942 				goto err_out;
5943 			}
5944 		}
5945 		ata_eh_freeze_port(ap);
5946 	}
5947 
5948 	if (start_dr)
5949 		devres_add(host->dev, start_dr);
5950 	host->flags |= ATA_HOST_STARTED;
5951 	return 0;
5952 
5953  err_out:
5954 	while (--i >= 0) {
5955 		struct ata_port *ap = host->ports[i];
5956 
5957 		if (ap->ops->port_stop)
5958 			ap->ops->port_stop(ap);
5959 	}
5960 	devres_free(start_dr);
5961 	return rc;
5962 }
5963 
5964 /**
5965  *	ata_sas_host_init - Initialize a host struct
5966  *	@host:	host to initialize
5967  *	@dev:	device host is attached to
5968  *	@flags:	host flags
5969  *	@ops:	port_ops
5970  *
5971  *	LOCKING:
5972  *	PCI/etc. bus probe sem.
5973  *
5974  */
5975 /* KILLME - the only user left is ipr */
5976 void ata_host_init(struct ata_host *host, struct device *dev,
5977 		   unsigned long flags, struct ata_port_operations *ops)
5978 {
5979 	spin_lock_init(&host->lock);
5980 	host->dev = dev;
5981 	host->flags = flags;
5982 	host->ops = ops;
5983 }
5984 
5985 
5986 static void async_port_probe(void *data, async_cookie_t cookie)
5987 {
5988 	int rc;
5989 	struct ata_port *ap = data;
5990 
5991 	/*
5992 	 * If we're not allowed to scan this host in parallel,
5993 	 * we need to wait until all previous scans have completed
5994 	 * before going further.
5995 	 * Jeff Garzik says this is only within a controller, so we
5996 	 * don't need to wait for port 0, only for later ports.
5997 	 */
5998 	if (!(ap->host->flags & ATA_HOST_PARALLEL_SCAN) && ap->port_no != 0)
5999 		async_synchronize_cookie(cookie);
6000 
6001 	/* probe */
6002 	if (ap->ops->error_handler) {
6003 		struct ata_eh_info *ehi = &ap->link.eh_info;
6004 		unsigned long flags;
6005 
6006 		/* kick EH for boot probing */
6007 		spin_lock_irqsave(ap->lock, flags);
6008 
6009 		ehi->probe_mask |= ATA_ALL_DEVICES;
6010 		ehi->action |= ATA_EH_RESET | ATA_EH_LPM;
6011 		ehi->flags |= ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET;
6012 
6013 		ap->pflags &= ~ATA_PFLAG_INITIALIZING;
6014 		ap->pflags |= ATA_PFLAG_LOADING;
6015 		ata_port_schedule_eh(ap);
6016 
6017 		spin_unlock_irqrestore(ap->lock, flags);
6018 
6019 		/* wait for EH to finish */
6020 		ata_port_wait_eh(ap);
6021 	} else {
6022 		DPRINTK("ata%u: bus probe begin\n", ap->print_id);
6023 		rc = ata_bus_probe(ap);
6024 		DPRINTK("ata%u: bus probe end\n", ap->print_id);
6025 
6026 		if (rc) {
6027 			/* FIXME: do something useful here?
6028 			 * Current libata behavior will
6029 			 * tear down everything when
6030 			 * the module is removed
6031 			 * or the h/w is unplugged.
6032 			 */
6033 		}
6034 	}
6035 
6036 	/* in order to keep device order, we need to synchronize at this point */
6037 	async_synchronize_cookie(cookie);
6038 
6039 	ata_scsi_scan_host(ap, 1);
6040 
6041 }
6042 /**
6043  *	ata_host_register - register initialized ATA host
6044  *	@host: ATA host to register
6045  *	@sht: template for SCSI host
6046  *
6047  *	Register initialized ATA host.  @host is allocated using
6048  *	ata_host_alloc() and fully initialized by LLD.  This function
6049  *	starts ports, registers @host with ATA and SCSI layers and
6050  *	probe registered devices.
6051  *
6052  *	LOCKING:
6053  *	Inherited from calling layer (may sleep).
6054  *
6055  *	RETURNS:
6056  *	0 on success, -errno otherwise.
6057  */
6058 int ata_host_register(struct ata_host *host, struct scsi_host_template *sht)
6059 {
6060 	int i, rc;
6061 
6062 	/* host must have been started */
6063 	if (!(host->flags & ATA_HOST_STARTED)) {
6064 		dev_printk(KERN_ERR, host->dev,
6065 			   "BUG: trying to register unstarted host\n");
6066 		WARN_ON(1);
6067 		return -EINVAL;
6068 	}
6069 
6070 	/* Blow away unused ports.  This happens when LLD can't
6071 	 * determine the exact number of ports to allocate at
6072 	 * allocation time.
6073 	 */
6074 	for (i = host->n_ports; host->ports[i]; i++)
6075 		kfree(host->ports[i]);
6076 
6077 	/* give ports names and add SCSI hosts */
6078 	for (i = 0; i < host->n_ports; i++)
6079 		host->ports[i]->print_id = ata_print_id++;
6080 
6081 	rc = ata_scsi_add_hosts(host, sht);
6082 	if (rc)
6083 		return rc;
6084 
6085 	/* associate with ACPI nodes */
6086 	ata_acpi_associate(host);
6087 
6088 	/* set cable, sata_spd_limit and report */
6089 	for (i = 0; i < host->n_ports; i++) {
6090 		struct ata_port *ap = host->ports[i];
6091 		unsigned long xfer_mask;
6092 
6093 		/* set SATA cable type if still unset */
6094 		if (ap->cbl == ATA_CBL_NONE && (ap->flags & ATA_FLAG_SATA))
6095 			ap->cbl = ATA_CBL_SATA;
6096 
6097 		/* init sata_spd_limit to the current value */
6098 		sata_link_init_spd(&ap->link);
6099 		if (ap->slave_link)
6100 			sata_link_init_spd(ap->slave_link);
6101 
6102 		/* print per-port info to dmesg */
6103 		xfer_mask = ata_pack_xfermask(ap->pio_mask, ap->mwdma_mask,
6104 					      ap->udma_mask);
6105 
6106 		if (!ata_port_is_dummy(ap)) {
6107 			ata_port_printk(ap, KERN_INFO,
6108 					"%cATA max %s %s\n",
6109 					(ap->flags & ATA_FLAG_SATA) ? 'S' : 'P',
6110 					ata_mode_string(xfer_mask),
6111 					ap->link.eh_info.desc);
6112 			ata_ehi_clear_desc(&ap->link.eh_info);
6113 		} else
6114 			ata_port_printk(ap, KERN_INFO, "DUMMY\n");
6115 	}
6116 
6117 	/* perform each probe asynchronously */
6118 	for (i = 0; i < host->n_ports; i++) {
6119 		struct ata_port *ap = host->ports[i];
6120 		async_schedule(async_port_probe, ap);
6121 	}
6122 
6123 	return 0;
6124 }
6125 
6126 /**
6127  *	ata_host_activate - start host, request IRQ and register it
6128  *	@host: target ATA host
6129  *	@irq: IRQ to request
6130  *	@irq_handler: irq_handler used when requesting IRQ
6131  *	@irq_flags: irq_flags used when requesting IRQ
6132  *	@sht: scsi_host_template to use when registering the host
6133  *
6134  *	After allocating an ATA host and initializing it, most libata
6135  *	LLDs perform three steps to activate the host - start host,
6136  *	request IRQ and register it.  This helper takes necessasry
6137  *	arguments and performs the three steps in one go.
6138  *
6139  *	An invalid IRQ skips the IRQ registration and expects the host to
6140  *	have set polling mode on the port. In this case, @irq_handler
6141  *	should be NULL.
6142  *
6143  *	LOCKING:
6144  *	Inherited from calling layer (may sleep).
6145  *
6146  *	RETURNS:
6147  *	0 on success, -errno otherwise.
6148  */
6149 int ata_host_activate(struct ata_host *host, int irq,
6150 		      irq_handler_t irq_handler, unsigned long irq_flags,
6151 		      struct scsi_host_template *sht)
6152 {
6153 	int i, rc;
6154 
6155 	rc = ata_host_start(host);
6156 	if (rc)
6157 		return rc;
6158 
6159 	/* Special case for polling mode */
6160 	if (!irq) {
6161 		WARN_ON(irq_handler);
6162 		return ata_host_register(host, sht);
6163 	}
6164 
6165 	rc = devm_request_irq(host->dev, irq, irq_handler, irq_flags,
6166 			      dev_driver_string(host->dev), host);
6167 	if (rc)
6168 		return rc;
6169 
6170 	for (i = 0; i < host->n_ports; i++)
6171 		ata_port_desc(host->ports[i], "irq %d", irq);
6172 
6173 	rc = ata_host_register(host, sht);
6174 	/* if failed, just free the IRQ and leave ports alone */
6175 	if (rc)
6176 		devm_free_irq(host->dev, irq, host);
6177 
6178 	return rc;
6179 }
6180 
6181 /**
6182  *	ata_port_detach - Detach ATA port in prepration of device removal
6183  *	@ap: ATA port to be detached
6184  *
6185  *	Detach all ATA devices and the associated SCSI devices of @ap;
6186  *	then, remove the associated SCSI host.  @ap is guaranteed to
6187  *	be quiescent on return from this function.
6188  *
6189  *	LOCKING:
6190  *	Kernel thread context (may sleep).
6191  */
6192 static void ata_port_detach(struct ata_port *ap)
6193 {
6194 	unsigned long flags;
6195 
6196 	if (!ap->ops->error_handler)
6197 		goto skip_eh;
6198 
6199 	/* tell EH we're leaving & flush EH */
6200 	spin_lock_irqsave(ap->lock, flags);
6201 	ap->pflags |= ATA_PFLAG_UNLOADING;
6202 	ata_port_schedule_eh(ap);
6203 	spin_unlock_irqrestore(ap->lock, flags);
6204 
6205 	/* wait till EH commits suicide */
6206 	ata_port_wait_eh(ap);
6207 
6208 	/* it better be dead now */
6209 	WARN_ON(!(ap->pflags & ATA_PFLAG_UNLOADED));
6210 
6211 	cancel_rearming_delayed_work(&ap->hotplug_task);
6212 
6213  skip_eh:
6214 	/* remove the associated SCSI host */
6215 	scsi_remove_host(ap->scsi_host);
6216 }
6217 
6218 /**
6219  *	ata_host_detach - Detach all ports of an ATA host
6220  *	@host: Host to detach
6221  *
6222  *	Detach all ports of @host.
6223  *
6224  *	LOCKING:
6225  *	Kernel thread context (may sleep).
6226  */
6227 void ata_host_detach(struct ata_host *host)
6228 {
6229 	int i;
6230 
6231 	for (i = 0; i < host->n_ports; i++)
6232 		ata_port_detach(host->ports[i]);
6233 
6234 	/* the host is dead now, dissociate ACPI */
6235 	ata_acpi_dissociate(host);
6236 }
6237 
6238 #ifdef CONFIG_PCI
6239 
6240 /**
6241  *	ata_pci_remove_one - PCI layer callback for device removal
6242  *	@pdev: PCI device that was removed
6243  *
6244  *	PCI layer indicates to libata via this hook that hot-unplug or
6245  *	module unload event has occurred.  Detach all ports.  Resource
6246  *	release is handled via devres.
6247  *
6248  *	LOCKING:
6249  *	Inherited from PCI layer (may sleep).
6250  */
6251 void ata_pci_remove_one(struct pci_dev *pdev)
6252 {
6253 	struct device *dev = &pdev->dev;
6254 	struct ata_host *host = dev_get_drvdata(dev);
6255 
6256 	ata_host_detach(host);
6257 }
6258 
6259 /* move to PCI subsystem */
6260 int pci_test_config_bits(struct pci_dev *pdev, const struct pci_bits *bits)
6261 {
6262 	unsigned long tmp = 0;
6263 
6264 	switch (bits->width) {
6265 	case 1: {
6266 		u8 tmp8 = 0;
6267 		pci_read_config_byte(pdev, bits->reg, &tmp8);
6268 		tmp = tmp8;
6269 		break;
6270 	}
6271 	case 2: {
6272 		u16 tmp16 = 0;
6273 		pci_read_config_word(pdev, bits->reg, &tmp16);
6274 		tmp = tmp16;
6275 		break;
6276 	}
6277 	case 4: {
6278 		u32 tmp32 = 0;
6279 		pci_read_config_dword(pdev, bits->reg, &tmp32);
6280 		tmp = tmp32;
6281 		break;
6282 	}
6283 
6284 	default:
6285 		return -EINVAL;
6286 	}
6287 
6288 	tmp &= bits->mask;
6289 
6290 	return (tmp == bits->val) ? 1 : 0;
6291 }
6292 
6293 #ifdef CONFIG_PM
6294 void ata_pci_device_do_suspend(struct pci_dev *pdev, pm_message_t mesg)
6295 {
6296 	pci_save_state(pdev);
6297 	pci_disable_device(pdev);
6298 
6299 	if (mesg.event & PM_EVENT_SLEEP)
6300 		pci_set_power_state(pdev, PCI_D3hot);
6301 }
6302 
6303 int ata_pci_device_do_resume(struct pci_dev *pdev)
6304 {
6305 	int rc;
6306 
6307 	pci_set_power_state(pdev, PCI_D0);
6308 	pci_restore_state(pdev);
6309 
6310 	rc = pcim_enable_device(pdev);
6311 	if (rc) {
6312 		dev_printk(KERN_ERR, &pdev->dev,
6313 			   "failed to enable device after resume (%d)\n", rc);
6314 		return rc;
6315 	}
6316 
6317 	pci_set_master(pdev);
6318 	return 0;
6319 }
6320 
6321 int ata_pci_device_suspend(struct pci_dev *pdev, pm_message_t mesg)
6322 {
6323 	struct ata_host *host = dev_get_drvdata(&pdev->dev);
6324 	int rc = 0;
6325 
6326 	rc = ata_host_suspend(host, mesg);
6327 	if (rc)
6328 		return rc;
6329 
6330 	ata_pci_device_do_suspend(pdev, mesg);
6331 
6332 	return 0;
6333 }
6334 
6335 int ata_pci_device_resume(struct pci_dev *pdev)
6336 {
6337 	struct ata_host *host = dev_get_drvdata(&pdev->dev);
6338 	int rc;
6339 
6340 	rc = ata_pci_device_do_resume(pdev);
6341 	if (rc == 0)
6342 		ata_host_resume(host);
6343 	return rc;
6344 }
6345 #endif /* CONFIG_PM */
6346 
6347 #endif /* CONFIG_PCI */
6348 
6349 static int __init ata_parse_force_one(char **cur,
6350 				      struct ata_force_ent *force_ent,
6351 				      const char **reason)
6352 {
6353 	/* FIXME: Currently, there's no way to tag init const data and
6354 	 * using __initdata causes build failure on some versions of
6355 	 * gcc.  Once __initdataconst is implemented, add const to the
6356 	 * following structure.
6357 	 */
6358 	static struct ata_force_param force_tbl[] __initdata = {
6359 		{ "40c",	.cbl		= ATA_CBL_PATA40 },
6360 		{ "80c",	.cbl		= ATA_CBL_PATA80 },
6361 		{ "short40c",	.cbl		= ATA_CBL_PATA40_SHORT },
6362 		{ "unk",	.cbl		= ATA_CBL_PATA_UNK },
6363 		{ "ign",	.cbl		= ATA_CBL_PATA_IGN },
6364 		{ "sata",	.cbl		= ATA_CBL_SATA },
6365 		{ "1.5Gbps",	.spd_limit	= 1 },
6366 		{ "3.0Gbps",	.spd_limit	= 2 },
6367 		{ "noncq",	.horkage_on	= ATA_HORKAGE_NONCQ },
6368 		{ "ncq",	.horkage_off	= ATA_HORKAGE_NONCQ },
6369 		{ "dump_id",	.horkage_on	= ATA_HORKAGE_DUMP_ID },
6370 		{ "pio0",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 0) },
6371 		{ "pio1",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 1) },
6372 		{ "pio2",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 2) },
6373 		{ "pio3",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 3) },
6374 		{ "pio4",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 4) },
6375 		{ "pio5",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 5) },
6376 		{ "pio6",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 6) },
6377 		{ "mwdma0",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 0) },
6378 		{ "mwdma1",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 1) },
6379 		{ "mwdma2",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 2) },
6380 		{ "mwdma3",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 3) },
6381 		{ "mwdma4",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 4) },
6382 		{ "udma0",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 0) },
6383 		{ "udma16",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 0) },
6384 		{ "udma/16",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 0) },
6385 		{ "udma1",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 1) },
6386 		{ "udma25",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 1) },
6387 		{ "udma/25",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 1) },
6388 		{ "udma2",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 2) },
6389 		{ "udma33",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 2) },
6390 		{ "udma/33",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 2) },
6391 		{ "udma3",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 3) },
6392 		{ "udma44",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 3) },
6393 		{ "udma/44",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 3) },
6394 		{ "udma4",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 4) },
6395 		{ "udma66",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 4) },
6396 		{ "udma/66",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 4) },
6397 		{ "udma5",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 5) },
6398 		{ "udma100",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 5) },
6399 		{ "udma/100",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 5) },
6400 		{ "udma6",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 6) },
6401 		{ "udma133",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 6) },
6402 		{ "udma/133",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 6) },
6403 		{ "udma7",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 7) },
6404 		{ "nohrst",	.lflags		= ATA_LFLAG_NO_HRST },
6405 		{ "nosrst",	.lflags		= ATA_LFLAG_NO_SRST },
6406 		{ "norst",	.lflags		= ATA_LFLAG_NO_HRST | ATA_LFLAG_NO_SRST },
6407 	};
6408 	char *start = *cur, *p = *cur;
6409 	char *id, *val, *endp;
6410 	const struct ata_force_param *match_fp = NULL;
6411 	int nr_matches = 0, i;
6412 
6413 	/* find where this param ends and update *cur */
6414 	while (*p != '\0' && *p != ',')
6415 		p++;
6416 
6417 	if (*p == '\0')
6418 		*cur = p;
6419 	else
6420 		*cur = p + 1;
6421 
6422 	*p = '\0';
6423 
6424 	/* parse */
6425 	p = strchr(start, ':');
6426 	if (!p) {
6427 		val = strstrip(start);
6428 		goto parse_val;
6429 	}
6430 	*p = '\0';
6431 
6432 	id = strstrip(start);
6433 	val = strstrip(p + 1);
6434 
6435 	/* parse id */
6436 	p = strchr(id, '.');
6437 	if (p) {
6438 		*p++ = '\0';
6439 		force_ent->device = simple_strtoul(p, &endp, 10);
6440 		if (p == endp || *endp != '\0') {
6441 			*reason = "invalid device";
6442 			return -EINVAL;
6443 		}
6444 	}
6445 
6446 	force_ent->port = simple_strtoul(id, &endp, 10);
6447 	if (p == endp || *endp != '\0') {
6448 		*reason = "invalid port/link";
6449 		return -EINVAL;
6450 	}
6451 
6452  parse_val:
6453 	/* parse val, allow shortcuts so that both 1.5 and 1.5Gbps work */
6454 	for (i = 0; i < ARRAY_SIZE(force_tbl); i++) {
6455 		const struct ata_force_param *fp = &force_tbl[i];
6456 
6457 		if (strncasecmp(val, fp->name, strlen(val)))
6458 			continue;
6459 
6460 		nr_matches++;
6461 		match_fp = fp;
6462 
6463 		if (strcasecmp(val, fp->name) == 0) {
6464 			nr_matches = 1;
6465 			break;
6466 		}
6467 	}
6468 
6469 	if (!nr_matches) {
6470 		*reason = "unknown value";
6471 		return -EINVAL;
6472 	}
6473 	if (nr_matches > 1) {
6474 		*reason = "ambigious value";
6475 		return -EINVAL;
6476 	}
6477 
6478 	force_ent->param = *match_fp;
6479 
6480 	return 0;
6481 }
6482 
6483 static void __init ata_parse_force_param(void)
6484 {
6485 	int idx = 0, size = 1;
6486 	int last_port = -1, last_device = -1;
6487 	char *p, *cur, *next;
6488 
6489 	/* calculate maximum number of params and allocate force_tbl */
6490 	for (p = ata_force_param_buf; *p; p++)
6491 		if (*p == ',')
6492 			size++;
6493 
6494 	ata_force_tbl = kzalloc(sizeof(ata_force_tbl[0]) * size, GFP_KERNEL);
6495 	if (!ata_force_tbl) {
6496 		printk(KERN_WARNING "ata: failed to extend force table, "
6497 		       "libata.force ignored\n");
6498 		return;
6499 	}
6500 
6501 	/* parse and populate the table */
6502 	for (cur = ata_force_param_buf; *cur != '\0'; cur = next) {
6503 		const char *reason = "";
6504 		struct ata_force_ent te = { .port = -1, .device = -1 };
6505 
6506 		next = cur;
6507 		if (ata_parse_force_one(&next, &te, &reason)) {
6508 			printk(KERN_WARNING "ata: failed to parse force "
6509 			       "parameter \"%s\" (%s)\n",
6510 			       cur, reason);
6511 			continue;
6512 		}
6513 
6514 		if (te.port == -1) {
6515 			te.port = last_port;
6516 			te.device = last_device;
6517 		}
6518 
6519 		ata_force_tbl[idx++] = te;
6520 
6521 		last_port = te.port;
6522 		last_device = te.device;
6523 	}
6524 
6525 	ata_force_tbl_size = idx;
6526 }
6527 
6528 static int __init ata_init(void)
6529 {
6530 	int rc = -ENOMEM;
6531 
6532 	ata_parse_force_param();
6533 
6534 	rc = ata_sff_init();
6535 	if (rc) {
6536 		kfree(ata_force_tbl);
6537 		return rc;
6538 	}
6539 
6540 	printk(KERN_DEBUG "libata version " DRV_VERSION " loaded.\n");
6541 	return 0;
6542 }
6543 
6544 static void __exit ata_exit(void)
6545 {
6546 	ata_sff_exit();
6547 	kfree(ata_force_tbl);
6548 }
6549 
6550 subsys_initcall(ata_init);
6551 module_exit(ata_exit);
6552 
6553 static DEFINE_RATELIMIT_STATE(ratelimit, HZ / 5, 1);
6554 
6555 int ata_ratelimit(void)
6556 {
6557 	return __ratelimit(&ratelimit);
6558 }
6559 
6560 /**
6561  *	ata_wait_register - wait until register value changes
6562  *	@reg: IO-mapped register
6563  *	@mask: Mask to apply to read register value
6564  *	@val: Wait condition
6565  *	@interval: polling interval in milliseconds
6566  *	@timeout: timeout in milliseconds
6567  *
6568  *	Waiting for some bits of register to change is a common
6569  *	operation for ATA controllers.  This function reads 32bit LE
6570  *	IO-mapped register @reg and tests for the following condition.
6571  *
6572  *	(*@reg & mask) != val
6573  *
6574  *	If the condition is met, it returns; otherwise, the process is
6575  *	repeated after @interval_msec until timeout.
6576  *
6577  *	LOCKING:
6578  *	Kernel thread context (may sleep)
6579  *
6580  *	RETURNS:
6581  *	The final register value.
6582  */
6583 u32 ata_wait_register(void __iomem *reg, u32 mask, u32 val,
6584 		      unsigned long interval, unsigned long timeout)
6585 {
6586 	unsigned long deadline;
6587 	u32 tmp;
6588 
6589 	tmp = ioread32(reg);
6590 
6591 	/* Calculate timeout _after_ the first read to make sure
6592 	 * preceding writes reach the controller before starting to
6593 	 * eat away the timeout.
6594 	 */
6595 	deadline = ata_deadline(jiffies, timeout);
6596 
6597 	while ((tmp & mask) == val && time_before(jiffies, deadline)) {
6598 		msleep(interval);
6599 		tmp = ioread32(reg);
6600 	}
6601 
6602 	return tmp;
6603 }
6604 
6605 /*
6606  * Dummy port_ops
6607  */
6608 static unsigned int ata_dummy_qc_issue(struct ata_queued_cmd *qc)
6609 {
6610 	return AC_ERR_SYSTEM;
6611 }
6612 
6613 static void ata_dummy_error_handler(struct ata_port *ap)
6614 {
6615 	/* truly dummy */
6616 }
6617 
6618 struct ata_port_operations ata_dummy_port_ops = {
6619 	.qc_prep		= ata_noop_qc_prep,
6620 	.qc_issue		= ata_dummy_qc_issue,
6621 	.error_handler		= ata_dummy_error_handler,
6622 };
6623 
6624 const struct ata_port_info ata_dummy_port_info = {
6625 	.port_ops		= &ata_dummy_port_ops,
6626 };
6627 
6628 /*
6629  * libata is essentially a library of internal helper functions for
6630  * low-level ATA host controller drivers.  As such, the API/ABI is
6631  * likely to change as new drivers are added and updated.
6632  * Do not depend on ABI/API stability.
6633  */
6634 EXPORT_SYMBOL_GPL(sata_deb_timing_normal);
6635 EXPORT_SYMBOL_GPL(sata_deb_timing_hotplug);
6636 EXPORT_SYMBOL_GPL(sata_deb_timing_long);
6637 EXPORT_SYMBOL_GPL(ata_base_port_ops);
6638 EXPORT_SYMBOL_GPL(sata_port_ops);
6639 EXPORT_SYMBOL_GPL(ata_dummy_port_ops);
6640 EXPORT_SYMBOL_GPL(ata_dummy_port_info);
6641 EXPORT_SYMBOL_GPL(ata_link_next);
6642 EXPORT_SYMBOL_GPL(ata_dev_next);
6643 EXPORT_SYMBOL_GPL(ata_std_bios_param);
6644 EXPORT_SYMBOL_GPL(ata_scsi_unlock_native_capacity);
6645 EXPORT_SYMBOL_GPL(ata_host_init);
6646 EXPORT_SYMBOL_GPL(ata_host_alloc);
6647 EXPORT_SYMBOL_GPL(ata_host_alloc_pinfo);
6648 EXPORT_SYMBOL_GPL(ata_slave_link_init);
6649 EXPORT_SYMBOL_GPL(ata_host_start);
6650 EXPORT_SYMBOL_GPL(ata_host_register);
6651 EXPORT_SYMBOL_GPL(ata_host_activate);
6652 EXPORT_SYMBOL_GPL(ata_host_detach);
6653 EXPORT_SYMBOL_GPL(ata_sg_init);
6654 EXPORT_SYMBOL_GPL(ata_qc_complete);
6655 EXPORT_SYMBOL_GPL(ata_qc_complete_multiple);
6656 EXPORT_SYMBOL_GPL(atapi_cmd_type);
6657 EXPORT_SYMBOL_GPL(ata_tf_to_fis);
6658 EXPORT_SYMBOL_GPL(ata_tf_from_fis);
6659 EXPORT_SYMBOL_GPL(ata_pack_xfermask);
6660 EXPORT_SYMBOL_GPL(ata_unpack_xfermask);
6661 EXPORT_SYMBOL_GPL(ata_xfer_mask2mode);
6662 EXPORT_SYMBOL_GPL(ata_xfer_mode2mask);
6663 EXPORT_SYMBOL_GPL(ata_xfer_mode2shift);
6664 EXPORT_SYMBOL_GPL(ata_mode_string);
6665 EXPORT_SYMBOL_GPL(ata_id_xfermask);
6666 EXPORT_SYMBOL_GPL(ata_do_set_mode);
6667 EXPORT_SYMBOL_GPL(ata_std_qc_defer);
6668 EXPORT_SYMBOL_GPL(ata_noop_qc_prep);
6669 EXPORT_SYMBOL_GPL(ata_dev_disable);
6670 EXPORT_SYMBOL_GPL(sata_set_spd);
6671 EXPORT_SYMBOL_GPL(ata_wait_after_reset);
6672 EXPORT_SYMBOL_GPL(sata_link_debounce);
6673 EXPORT_SYMBOL_GPL(sata_link_resume);
6674 EXPORT_SYMBOL_GPL(ata_std_prereset);
6675 EXPORT_SYMBOL_GPL(sata_link_hardreset);
6676 EXPORT_SYMBOL_GPL(sata_std_hardreset);
6677 EXPORT_SYMBOL_GPL(ata_std_postreset);
6678 EXPORT_SYMBOL_GPL(ata_dev_classify);
6679 EXPORT_SYMBOL_GPL(ata_dev_pair);
6680 EXPORT_SYMBOL_GPL(ata_ratelimit);
6681 EXPORT_SYMBOL_GPL(ata_wait_register);
6682 EXPORT_SYMBOL_GPL(ata_scsi_queuecmd);
6683 EXPORT_SYMBOL_GPL(ata_scsi_slave_config);
6684 EXPORT_SYMBOL_GPL(ata_scsi_slave_destroy);
6685 EXPORT_SYMBOL_GPL(ata_scsi_change_queue_depth);
6686 EXPORT_SYMBOL_GPL(sata_scr_valid);
6687 EXPORT_SYMBOL_GPL(sata_scr_read);
6688 EXPORT_SYMBOL_GPL(sata_scr_write);
6689 EXPORT_SYMBOL_GPL(sata_scr_write_flush);
6690 EXPORT_SYMBOL_GPL(ata_link_online);
6691 EXPORT_SYMBOL_GPL(ata_link_offline);
6692 #ifdef CONFIG_PM
6693 EXPORT_SYMBOL_GPL(ata_host_suspend);
6694 EXPORT_SYMBOL_GPL(ata_host_resume);
6695 #endif /* CONFIG_PM */
6696 EXPORT_SYMBOL_GPL(ata_id_string);
6697 EXPORT_SYMBOL_GPL(ata_id_c_string);
6698 EXPORT_SYMBOL_GPL(ata_do_dev_read_id);
6699 EXPORT_SYMBOL_GPL(ata_scsi_simulate);
6700 
6701 EXPORT_SYMBOL_GPL(ata_pio_need_iordy);
6702 EXPORT_SYMBOL_GPL(ata_timing_find_mode);
6703 EXPORT_SYMBOL_GPL(ata_timing_compute);
6704 EXPORT_SYMBOL_GPL(ata_timing_merge);
6705 EXPORT_SYMBOL_GPL(ata_timing_cycle2mode);
6706 
6707 #ifdef CONFIG_PCI
6708 EXPORT_SYMBOL_GPL(pci_test_config_bits);
6709 EXPORT_SYMBOL_GPL(ata_pci_remove_one);
6710 #ifdef CONFIG_PM
6711 EXPORT_SYMBOL_GPL(ata_pci_device_do_suspend);
6712 EXPORT_SYMBOL_GPL(ata_pci_device_do_resume);
6713 EXPORT_SYMBOL_GPL(ata_pci_device_suspend);
6714 EXPORT_SYMBOL_GPL(ata_pci_device_resume);
6715 #endif /* CONFIG_PM */
6716 #endif /* CONFIG_PCI */
6717 
6718 EXPORT_SYMBOL_GPL(__ata_ehi_push_desc);
6719 EXPORT_SYMBOL_GPL(ata_ehi_push_desc);
6720 EXPORT_SYMBOL_GPL(ata_ehi_clear_desc);
6721 EXPORT_SYMBOL_GPL(ata_port_desc);
6722 #ifdef CONFIG_PCI
6723 EXPORT_SYMBOL_GPL(ata_port_pbar_desc);
6724 #endif /* CONFIG_PCI */
6725 EXPORT_SYMBOL_GPL(ata_port_schedule_eh);
6726 EXPORT_SYMBOL_GPL(ata_link_abort);
6727 EXPORT_SYMBOL_GPL(ata_port_abort);
6728 EXPORT_SYMBOL_GPL(ata_port_freeze);
6729 EXPORT_SYMBOL_GPL(sata_async_notification);
6730 EXPORT_SYMBOL_GPL(ata_eh_freeze_port);
6731 EXPORT_SYMBOL_GPL(ata_eh_thaw_port);
6732 EXPORT_SYMBOL_GPL(ata_eh_qc_complete);
6733 EXPORT_SYMBOL_GPL(ata_eh_qc_retry);
6734 EXPORT_SYMBOL_GPL(ata_eh_analyze_ncq_error);
6735 EXPORT_SYMBOL_GPL(ata_do_eh);
6736 EXPORT_SYMBOL_GPL(ata_std_error_handler);
6737 
6738 EXPORT_SYMBOL_GPL(ata_cable_40wire);
6739 EXPORT_SYMBOL_GPL(ata_cable_80wire);
6740 EXPORT_SYMBOL_GPL(ata_cable_unknown);
6741 EXPORT_SYMBOL_GPL(ata_cable_ignore);
6742 EXPORT_SYMBOL_GPL(ata_cable_sata);
6743