xref: /linux/drivers/ata/libata-core.c (revision f3449bf31d352f70c80a7993c272a7854ae98086)
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 #include "libata-transport.h"
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 void ata_dev_xfermask(struct ata_device *dev);
95 static unsigned long ata_dev_blacklisted(const struct ata_device *dev);
96 
97 unsigned int ata_print_id = 1;
98 
99 struct ata_force_param {
100 	const char	*name;
101 	unsigned int	cbl;
102 	int		spd_limit;
103 	unsigned long	xfer_mask;
104 	unsigned int	horkage_on;
105 	unsigned int	horkage_off;
106 	unsigned int	lflags;
107 };
108 
109 struct ata_force_ent {
110 	int			port;
111 	int			device;
112 	struct ata_force_param	param;
113 };
114 
115 static struct ata_force_ent *ata_force_tbl;
116 static int ata_force_tbl_size;
117 
118 static char ata_force_param_buf[PAGE_SIZE] __initdata;
119 /* param_buf is thrown away after initialization, disallow read */
120 module_param_string(force, ata_force_param_buf, sizeof(ata_force_param_buf), 0);
121 MODULE_PARM_DESC(force, "Force ATA configurations including cable type, link speed and transfer mode (see Documentation/kernel-parameters.txt for details)");
122 
123 static int atapi_enabled = 1;
124 module_param(atapi_enabled, int, 0444);
125 MODULE_PARM_DESC(atapi_enabled, "Enable discovery of ATAPI devices (0=off, 1=on [default])");
126 
127 static int atapi_dmadir = 0;
128 module_param(atapi_dmadir, int, 0444);
129 MODULE_PARM_DESC(atapi_dmadir, "Enable ATAPI DMADIR bridge support (0=off [default], 1=on)");
130 
131 int atapi_passthru16 = 1;
132 module_param(atapi_passthru16, int, 0444);
133 MODULE_PARM_DESC(atapi_passthru16, "Enable ATA_16 passthru for ATAPI devices (0=off, 1=on [default])");
134 
135 int libata_fua = 0;
136 module_param_named(fua, libata_fua, int, 0444);
137 MODULE_PARM_DESC(fua, "FUA support (0=off [default], 1=on)");
138 
139 static int ata_ignore_hpa;
140 module_param_named(ignore_hpa, ata_ignore_hpa, int, 0644);
141 MODULE_PARM_DESC(ignore_hpa, "Ignore HPA limit (0=keep BIOS limits, 1=ignore limits, using full disk)");
142 
143 static int libata_dma_mask = ATA_DMA_MASK_ATA|ATA_DMA_MASK_ATAPI|ATA_DMA_MASK_CFA;
144 module_param_named(dma, libata_dma_mask, int, 0444);
145 MODULE_PARM_DESC(dma, "DMA enable/disable (0x1==ATA, 0x2==ATAPI, 0x4==CF)");
146 
147 static int ata_probe_timeout;
148 module_param(ata_probe_timeout, int, 0444);
149 MODULE_PARM_DESC(ata_probe_timeout, "Set ATA probing timeout (seconds)");
150 
151 int libata_noacpi = 0;
152 module_param_named(noacpi, libata_noacpi, int, 0444);
153 MODULE_PARM_DESC(noacpi, "Disable the use of ACPI in probe/suspend/resume (0=off [default], 1=on)");
154 
155 int libata_allow_tpm = 0;
156 module_param_named(allow_tpm, libata_allow_tpm, int, 0444);
157 MODULE_PARM_DESC(allow_tpm, "Permit the use of TPM commands (0=off [default], 1=on)");
158 
159 static int atapi_an;
160 module_param(atapi_an, int, 0444);
161 MODULE_PARM_DESC(atapi_an, "Enable ATAPI AN media presence notification (0=0ff [default], 1=on)");
162 
163 MODULE_AUTHOR("Jeff Garzik");
164 MODULE_DESCRIPTION("Library module for ATA devices");
165 MODULE_LICENSE("GPL");
166 MODULE_VERSION(DRV_VERSION);
167 
168 
169 static bool ata_sstatus_online(u32 sstatus)
170 {
171 	return (sstatus & 0xf) == 0x3;
172 }
173 
174 /**
175  *	ata_link_next - link iteration helper
176  *	@link: the previous link, NULL to start
177  *	@ap: ATA port containing links to iterate
178  *	@mode: iteration mode, one of ATA_LITER_*
179  *
180  *	LOCKING:
181  *	Host lock or EH context.
182  *
183  *	RETURNS:
184  *	Pointer to the next link.
185  */
186 struct ata_link *ata_link_next(struct ata_link *link, struct ata_port *ap,
187 			       enum ata_link_iter_mode mode)
188 {
189 	BUG_ON(mode != ATA_LITER_EDGE &&
190 	       mode != ATA_LITER_PMP_FIRST && mode != ATA_LITER_HOST_FIRST);
191 
192 	/* NULL link indicates start of iteration */
193 	if (!link)
194 		switch (mode) {
195 		case ATA_LITER_EDGE:
196 		case ATA_LITER_PMP_FIRST:
197 			if (sata_pmp_attached(ap))
198 				return ap->pmp_link;
199 			/* fall through */
200 		case ATA_LITER_HOST_FIRST:
201 			return &ap->link;
202 		}
203 
204 	/* we just iterated over the host link, what's next? */
205 	if (link == &ap->link)
206 		switch (mode) {
207 		case ATA_LITER_HOST_FIRST:
208 			if (sata_pmp_attached(ap))
209 				return ap->pmp_link;
210 			/* fall through */
211 		case ATA_LITER_PMP_FIRST:
212 			if (unlikely(ap->slave_link))
213 				return ap->slave_link;
214 			/* fall through */
215 		case ATA_LITER_EDGE:
216 			return NULL;
217 		}
218 
219 	/* slave_link excludes PMP */
220 	if (unlikely(link == ap->slave_link))
221 		return NULL;
222 
223 	/* we were over a PMP link */
224 	if (++link < ap->pmp_link + ap->nr_pmp_links)
225 		return link;
226 
227 	if (mode == ATA_LITER_PMP_FIRST)
228 		return &ap->link;
229 
230 	return NULL;
231 }
232 
233 /**
234  *	ata_dev_next - device iteration helper
235  *	@dev: the previous device, NULL to start
236  *	@link: ATA link containing devices to iterate
237  *	@mode: iteration mode, one of ATA_DITER_*
238  *
239  *	LOCKING:
240  *	Host lock or EH context.
241  *
242  *	RETURNS:
243  *	Pointer to the next device.
244  */
245 struct ata_device *ata_dev_next(struct ata_device *dev, struct ata_link *link,
246 				enum ata_dev_iter_mode mode)
247 {
248 	BUG_ON(mode != ATA_DITER_ENABLED && mode != ATA_DITER_ENABLED_REVERSE &&
249 	       mode != ATA_DITER_ALL && mode != ATA_DITER_ALL_REVERSE);
250 
251 	/* NULL dev indicates start of iteration */
252 	if (!dev)
253 		switch (mode) {
254 		case ATA_DITER_ENABLED:
255 		case ATA_DITER_ALL:
256 			dev = link->device;
257 			goto check;
258 		case ATA_DITER_ENABLED_REVERSE:
259 		case ATA_DITER_ALL_REVERSE:
260 			dev = link->device + ata_link_max_devices(link) - 1;
261 			goto check;
262 		}
263 
264  next:
265 	/* move to the next one */
266 	switch (mode) {
267 	case ATA_DITER_ENABLED:
268 	case ATA_DITER_ALL:
269 		if (++dev < link->device + ata_link_max_devices(link))
270 			goto check;
271 		return NULL;
272 	case ATA_DITER_ENABLED_REVERSE:
273 	case ATA_DITER_ALL_REVERSE:
274 		if (--dev >= link->device)
275 			goto check;
276 		return NULL;
277 	}
278 
279  check:
280 	if ((mode == ATA_DITER_ENABLED || mode == ATA_DITER_ENABLED_REVERSE) &&
281 	    !ata_dev_enabled(dev))
282 		goto next;
283 	return dev;
284 }
285 
286 /**
287  *	ata_dev_phys_link - find physical link for a device
288  *	@dev: ATA device to look up physical link for
289  *
290  *	Look up physical link which @dev is attached to.  Note that
291  *	this is different from @dev->link only when @dev is on slave
292  *	link.  For all other cases, it's the same as @dev->link.
293  *
294  *	LOCKING:
295  *	Don't care.
296  *
297  *	RETURNS:
298  *	Pointer to the found physical link.
299  */
300 struct ata_link *ata_dev_phys_link(struct ata_device *dev)
301 {
302 	struct ata_port *ap = dev->link->ap;
303 
304 	if (!ap->slave_link)
305 		return dev->link;
306 	if (!dev->devno)
307 		return &ap->link;
308 	return ap->slave_link;
309 }
310 
311 /**
312  *	ata_force_cbl - force cable type according to libata.force
313  *	@ap: ATA port of interest
314  *
315  *	Force cable type according to libata.force and whine about it.
316  *	The last entry which has matching port number is used, so it
317  *	can be specified as part of device force parameters.  For
318  *	example, both "a:40c,1.00:udma4" and "1.00:40c,udma4" have the
319  *	same effect.
320  *
321  *	LOCKING:
322  *	EH context.
323  */
324 void ata_force_cbl(struct ata_port *ap)
325 {
326 	int i;
327 
328 	for (i = ata_force_tbl_size - 1; i >= 0; i--) {
329 		const struct ata_force_ent *fe = &ata_force_tbl[i];
330 
331 		if (fe->port != -1 && fe->port != ap->print_id)
332 			continue;
333 
334 		if (fe->param.cbl == ATA_CBL_NONE)
335 			continue;
336 
337 		ap->cbl = fe->param.cbl;
338 		ata_port_printk(ap, KERN_NOTICE,
339 				"FORCE: cable set to %s\n", fe->param.name);
340 		return;
341 	}
342 }
343 
344 /**
345  *	ata_force_link_limits - force link limits according to libata.force
346  *	@link: ATA link of interest
347  *
348  *	Force link flags and SATA spd limit according to libata.force
349  *	and whine about it.  When only the port part is specified
350  *	(e.g. 1:), the limit applies to all links connected to both
351  *	the host link and all fan-out ports connected via PMP.  If the
352  *	device part is specified as 0 (e.g. 1.00:), it specifies the
353  *	first fan-out link not the host link.  Device number 15 always
354  *	points to the host link whether PMP is attached or not.  If the
355  *	controller has slave link, device number 16 points to it.
356  *
357  *	LOCKING:
358  *	EH context.
359  */
360 static void ata_force_link_limits(struct ata_link *link)
361 {
362 	bool did_spd = false;
363 	int linkno = link->pmp;
364 	int i;
365 
366 	if (ata_is_host_link(link))
367 		linkno += 15;
368 
369 	for (i = ata_force_tbl_size - 1; i >= 0; i--) {
370 		const struct ata_force_ent *fe = &ata_force_tbl[i];
371 
372 		if (fe->port != -1 && fe->port != link->ap->print_id)
373 			continue;
374 
375 		if (fe->device != -1 && fe->device != linkno)
376 			continue;
377 
378 		/* only honor the first spd limit */
379 		if (!did_spd && fe->param.spd_limit) {
380 			link->hw_sata_spd_limit = (1 << fe->param.spd_limit) - 1;
381 			ata_link_printk(link, KERN_NOTICE,
382 					"FORCE: PHY spd limit set to %s\n",
383 					fe->param.name);
384 			did_spd = true;
385 		}
386 
387 		/* let lflags stack */
388 		if (fe->param.lflags) {
389 			link->flags |= fe->param.lflags;
390 			ata_link_printk(link, KERN_NOTICE,
391 					"FORCE: link flag 0x%x forced -> 0x%x\n",
392 					fe->param.lflags, link->flags);
393 		}
394 	}
395 }
396 
397 /**
398  *	ata_force_xfermask - force xfermask according to libata.force
399  *	@dev: ATA device of interest
400  *
401  *	Force xfer_mask according to libata.force and whine about it.
402  *	For consistency with link selection, device number 15 selects
403  *	the first device connected to the host link.
404  *
405  *	LOCKING:
406  *	EH context.
407  */
408 static void ata_force_xfermask(struct ata_device *dev)
409 {
410 	int devno = dev->link->pmp + dev->devno;
411 	int alt_devno = devno;
412 	int i;
413 
414 	/* allow n.15/16 for devices attached to host port */
415 	if (ata_is_host_link(dev->link))
416 		alt_devno += 15;
417 
418 	for (i = ata_force_tbl_size - 1; i >= 0; i--) {
419 		const struct ata_force_ent *fe = &ata_force_tbl[i];
420 		unsigned long pio_mask, mwdma_mask, udma_mask;
421 
422 		if (fe->port != -1 && fe->port != dev->link->ap->print_id)
423 			continue;
424 
425 		if (fe->device != -1 && fe->device != devno &&
426 		    fe->device != alt_devno)
427 			continue;
428 
429 		if (!fe->param.xfer_mask)
430 			continue;
431 
432 		ata_unpack_xfermask(fe->param.xfer_mask,
433 				    &pio_mask, &mwdma_mask, &udma_mask);
434 		if (udma_mask)
435 			dev->udma_mask = udma_mask;
436 		else if (mwdma_mask) {
437 			dev->udma_mask = 0;
438 			dev->mwdma_mask = mwdma_mask;
439 		} else {
440 			dev->udma_mask = 0;
441 			dev->mwdma_mask = 0;
442 			dev->pio_mask = pio_mask;
443 		}
444 
445 		ata_dev_printk(dev, KERN_NOTICE,
446 			"FORCE: xfer_mask set to %s\n", fe->param.name);
447 		return;
448 	}
449 }
450 
451 /**
452  *	ata_force_horkage - force horkage according to libata.force
453  *	@dev: ATA device of interest
454  *
455  *	Force horkage according to libata.force and whine about it.
456  *	For consistency with link selection, device number 15 selects
457  *	the first device connected to the host link.
458  *
459  *	LOCKING:
460  *	EH context.
461  */
462 static void ata_force_horkage(struct ata_device *dev)
463 {
464 	int devno = dev->link->pmp + dev->devno;
465 	int alt_devno = devno;
466 	int i;
467 
468 	/* allow n.15/16 for devices attached to host port */
469 	if (ata_is_host_link(dev->link))
470 		alt_devno += 15;
471 
472 	for (i = 0; i < ata_force_tbl_size; i++) {
473 		const struct ata_force_ent *fe = &ata_force_tbl[i];
474 
475 		if (fe->port != -1 && fe->port != dev->link->ap->print_id)
476 			continue;
477 
478 		if (fe->device != -1 && fe->device != devno &&
479 		    fe->device != alt_devno)
480 			continue;
481 
482 		if (!(~dev->horkage & fe->param.horkage_on) &&
483 		    !(dev->horkage & fe->param.horkage_off))
484 			continue;
485 
486 		dev->horkage |= fe->param.horkage_on;
487 		dev->horkage &= ~fe->param.horkage_off;
488 
489 		ata_dev_printk(dev, KERN_NOTICE,
490 			"FORCE: horkage modified (%s)\n", fe->param.name);
491 	}
492 }
493 
494 /**
495  *	atapi_cmd_type - Determine ATAPI command type from SCSI opcode
496  *	@opcode: SCSI opcode
497  *
498  *	Determine ATAPI command type from @opcode.
499  *
500  *	LOCKING:
501  *	None.
502  *
503  *	RETURNS:
504  *	ATAPI_{READ|WRITE|READ_CD|PASS_THRU|MISC}
505  */
506 int atapi_cmd_type(u8 opcode)
507 {
508 	switch (opcode) {
509 	case GPCMD_READ_10:
510 	case GPCMD_READ_12:
511 		return ATAPI_READ;
512 
513 	case GPCMD_WRITE_10:
514 	case GPCMD_WRITE_12:
515 	case GPCMD_WRITE_AND_VERIFY_10:
516 		return ATAPI_WRITE;
517 
518 	case GPCMD_READ_CD:
519 	case GPCMD_READ_CD_MSF:
520 		return ATAPI_READ_CD;
521 
522 	case ATA_16:
523 	case ATA_12:
524 		if (atapi_passthru16)
525 			return ATAPI_PASS_THRU;
526 		/* fall thru */
527 	default:
528 		return ATAPI_MISC;
529 	}
530 }
531 
532 /**
533  *	ata_tf_to_fis - Convert ATA taskfile to SATA FIS structure
534  *	@tf: Taskfile to convert
535  *	@pmp: Port multiplier port
536  *	@is_cmd: This FIS is for command
537  *	@fis: Buffer into which data will output
538  *
539  *	Converts a standard ATA taskfile to a Serial ATA
540  *	FIS structure (Register - Host to Device).
541  *
542  *	LOCKING:
543  *	Inherited from caller.
544  */
545 void ata_tf_to_fis(const struct ata_taskfile *tf, u8 pmp, int is_cmd, u8 *fis)
546 {
547 	fis[0] = 0x27;			/* Register - Host to Device FIS */
548 	fis[1] = pmp & 0xf;		/* Port multiplier number*/
549 	if (is_cmd)
550 		fis[1] |= (1 << 7);	/* bit 7 indicates Command FIS */
551 
552 	fis[2] = tf->command;
553 	fis[3] = tf->feature;
554 
555 	fis[4] = tf->lbal;
556 	fis[5] = tf->lbam;
557 	fis[6] = tf->lbah;
558 	fis[7] = tf->device;
559 
560 	fis[8] = tf->hob_lbal;
561 	fis[9] = tf->hob_lbam;
562 	fis[10] = tf->hob_lbah;
563 	fis[11] = tf->hob_feature;
564 
565 	fis[12] = tf->nsect;
566 	fis[13] = tf->hob_nsect;
567 	fis[14] = 0;
568 	fis[15] = tf->ctl;
569 
570 	fis[16] = 0;
571 	fis[17] = 0;
572 	fis[18] = 0;
573 	fis[19] = 0;
574 }
575 
576 /**
577  *	ata_tf_from_fis - Convert SATA FIS to ATA taskfile
578  *	@fis: Buffer from which data will be input
579  *	@tf: Taskfile to output
580  *
581  *	Converts a serial ATA FIS structure to a standard ATA taskfile.
582  *
583  *	LOCKING:
584  *	Inherited from caller.
585  */
586 
587 void ata_tf_from_fis(const u8 *fis, struct ata_taskfile *tf)
588 {
589 	tf->command	= fis[2];	/* status */
590 	tf->feature	= fis[3];	/* error */
591 
592 	tf->lbal	= fis[4];
593 	tf->lbam	= fis[5];
594 	tf->lbah	= fis[6];
595 	tf->device	= fis[7];
596 
597 	tf->hob_lbal	= fis[8];
598 	tf->hob_lbam	= fis[9];
599 	tf->hob_lbah	= fis[10];
600 
601 	tf->nsect	= fis[12];
602 	tf->hob_nsect	= fis[13];
603 }
604 
605 static const u8 ata_rw_cmds[] = {
606 	/* pio multi */
607 	ATA_CMD_READ_MULTI,
608 	ATA_CMD_WRITE_MULTI,
609 	ATA_CMD_READ_MULTI_EXT,
610 	ATA_CMD_WRITE_MULTI_EXT,
611 	0,
612 	0,
613 	0,
614 	ATA_CMD_WRITE_MULTI_FUA_EXT,
615 	/* pio */
616 	ATA_CMD_PIO_READ,
617 	ATA_CMD_PIO_WRITE,
618 	ATA_CMD_PIO_READ_EXT,
619 	ATA_CMD_PIO_WRITE_EXT,
620 	0,
621 	0,
622 	0,
623 	0,
624 	/* dma */
625 	ATA_CMD_READ,
626 	ATA_CMD_WRITE,
627 	ATA_CMD_READ_EXT,
628 	ATA_CMD_WRITE_EXT,
629 	0,
630 	0,
631 	0,
632 	ATA_CMD_WRITE_FUA_EXT
633 };
634 
635 /**
636  *	ata_rwcmd_protocol - set taskfile r/w commands and protocol
637  *	@tf: command to examine and configure
638  *	@dev: device tf belongs to
639  *
640  *	Examine the device configuration and tf->flags to calculate
641  *	the proper read/write commands and protocol to use.
642  *
643  *	LOCKING:
644  *	caller.
645  */
646 static int ata_rwcmd_protocol(struct ata_taskfile *tf, struct ata_device *dev)
647 {
648 	u8 cmd;
649 
650 	int index, fua, lba48, write;
651 
652 	fua = (tf->flags & ATA_TFLAG_FUA) ? 4 : 0;
653 	lba48 = (tf->flags & ATA_TFLAG_LBA48) ? 2 : 0;
654 	write = (tf->flags & ATA_TFLAG_WRITE) ? 1 : 0;
655 
656 	if (dev->flags & ATA_DFLAG_PIO) {
657 		tf->protocol = ATA_PROT_PIO;
658 		index = dev->multi_count ? 0 : 8;
659 	} else if (lba48 && (dev->link->ap->flags & ATA_FLAG_PIO_LBA48)) {
660 		/* Unable to use DMA due to host limitation */
661 		tf->protocol = ATA_PROT_PIO;
662 		index = dev->multi_count ? 0 : 8;
663 	} else {
664 		tf->protocol = ATA_PROT_DMA;
665 		index = 16;
666 	}
667 
668 	cmd = ata_rw_cmds[index + fua + lba48 + write];
669 	if (cmd) {
670 		tf->command = cmd;
671 		return 0;
672 	}
673 	return -1;
674 }
675 
676 /**
677  *	ata_tf_read_block - Read block address from ATA taskfile
678  *	@tf: ATA taskfile of interest
679  *	@dev: ATA device @tf belongs to
680  *
681  *	LOCKING:
682  *	None.
683  *
684  *	Read block address from @tf.  This function can handle all
685  *	three address formats - LBA, LBA48 and CHS.  tf->protocol and
686  *	flags select the address format to use.
687  *
688  *	RETURNS:
689  *	Block address read from @tf.
690  */
691 u64 ata_tf_read_block(struct ata_taskfile *tf, struct ata_device *dev)
692 {
693 	u64 block = 0;
694 
695 	if (tf->flags & ATA_TFLAG_LBA) {
696 		if (tf->flags & ATA_TFLAG_LBA48) {
697 			block |= (u64)tf->hob_lbah << 40;
698 			block |= (u64)tf->hob_lbam << 32;
699 			block |= (u64)tf->hob_lbal << 24;
700 		} else
701 			block |= (tf->device & 0xf) << 24;
702 
703 		block |= tf->lbah << 16;
704 		block |= tf->lbam << 8;
705 		block |= tf->lbal;
706 	} else {
707 		u32 cyl, head, sect;
708 
709 		cyl = tf->lbam | (tf->lbah << 8);
710 		head = tf->device & 0xf;
711 		sect = tf->lbal;
712 
713 		if (!sect) {
714 			ata_dev_printk(dev, KERN_WARNING, "device reported "
715 				       "invalid CHS sector 0\n");
716 			sect = 1; /* oh well */
717 		}
718 
719 		block = (cyl * dev->heads + head) * dev->sectors + sect - 1;
720 	}
721 
722 	return block;
723 }
724 
725 /**
726  *	ata_build_rw_tf - Build ATA taskfile for given read/write request
727  *	@tf: Target ATA taskfile
728  *	@dev: ATA device @tf belongs to
729  *	@block: Block address
730  *	@n_block: Number of blocks
731  *	@tf_flags: RW/FUA etc...
732  *	@tag: tag
733  *
734  *	LOCKING:
735  *	None.
736  *
737  *	Build ATA taskfile @tf for read/write request described by
738  *	@block, @n_block, @tf_flags and @tag on @dev.
739  *
740  *	RETURNS:
741  *
742  *	0 on success, -ERANGE if the request is too large for @dev,
743  *	-EINVAL if the request is invalid.
744  */
745 int ata_build_rw_tf(struct ata_taskfile *tf, struct ata_device *dev,
746 		    u64 block, u32 n_block, unsigned int tf_flags,
747 		    unsigned int tag)
748 {
749 	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
750 	tf->flags |= tf_flags;
751 
752 	if (ata_ncq_enabled(dev) && likely(tag != ATA_TAG_INTERNAL)) {
753 		/* yay, NCQ */
754 		if (!lba_48_ok(block, n_block))
755 			return -ERANGE;
756 
757 		tf->protocol = ATA_PROT_NCQ;
758 		tf->flags |= ATA_TFLAG_LBA | ATA_TFLAG_LBA48;
759 
760 		if (tf->flags & ATA_TFLAG_WRITE)
761 			tf->command = ATA_CMD_FPDMA_WRITE;
762 		else
763 			tf->command = ATA_CMD_FPDMA_READ;
764 
765 		tf->nsect = tag << 3;
766 		tf->hob_feature = (n_block >> 8) & 0xff;
767 		tf->feature = n_block & 0xff;
768 
769 		tf->hob_lbah = (block >> 40) & 0xff;
770 		tf->hob_lbam = (block >> 32) & 0xff;
771 		tf->hob_lbal = (block >> 24) & 0xff;
772 		tf->lbah = (block >> 16) & 0xff;
773 		tf->lbam = (block >> 8) & 0xff;
774 		tf->lbal = block & 0xff;
775 
776 		tf->device = 1 << 6;
777 		if (tf->flags & ATA_TFLAG_FUA)
778 			tf->device |= 1 << 7;
779 	} else if (dev->flags & ATA_DFLAG_LBA) {
780 		tf->flags |= ATA_TFLAG_LBA;
781 
782 		if (lba_28_ok(block, n_block)) {
783 			/* use LBA28 */
784 			tf->device |= (block >> 24) & 0xf;
785 		} else if (lba_48_ok(block, n_block)) {
786 			if (!(dev->flags & ATA_DFLAG_LBA48))
787 				return -ERANGE;
788 
789 			/* use LBA48 */
790 			tf->flags |= ATA_TFLAG_LBA48;
791 
792 			tf->hob_nsect = (n_block >> 8) & 0xff;
793 
794 			tf->hob_lbah = (block >> 40) & 0xff;
795 			tf->hob_lbam = (block >> 32) & 0xff;
796 			tf->hob_lbal = (block >> 24) & 0xff;
797 		} else
798 			/* request too large even for LBA48 */
799 			return -ERANGE;
800 
801 		if (unlikely(ata_rwcmd_protocol(tf, dev) < 0))
802 			return -EINVAL;
803 
804 		tf->nsect = n_block & 0xff;
805 
806 		tf->lbah = (block >> 16) & 0xff;
807 		tf->lbam = (block >> 8) & 0xff;
808 		tf->lbal = block & 0xff;
809 
810 		tf->device |= ATA_LBA;
811 	} else {
812 		/* CHS */
813 		u32 sect, head, cyl, track;
814 
815 		/* The request -may- be too large for CHS addressing. */
816 		if (!lba_28_ok(block, n_block))
817 			return -ERANGE;
818 
819 		if (unlikely(ata_rwcmd_protocol(tf, dev) < 0))
820 			return -EINVAL;
821 
822 		/* Convert LBA to CHS */
823 		track = (u32)block / dev->sectors;
824 		cyl   = track / dev->heads;
825 		head  = track % dev->heads;
826 		sect  = (u32)block % dev->sectors + 1;
827 
828 		DPRINTK("block %u track %u cyl %u head %u sect %u\n",
829 			(u32)block, track, cyl, head, sect);
830 
831 		/* Check whether the converted CHS can fit.
832 		   Cylinder: 0-65535
833 		   Head: 0-15
834 		   Sector: 1-255*/
835 		if ((cyl >> 16) || (head >> 4) || (sect >> 8) || (!sect))
836 			return -ERANGE;
837 
838 		tf->nsect = n_block & 0xff; /* Sector count 0 means 256 sectors */
839 		tf->lbal = sect;
840 		tf->lbam = cyl;
841 		tf->lbah = cyl >> 8;
842 		tf->device |= head;
843 	}
844 
845 	return 0;
846 }
847 
848 /**
849  *	ata_pack_xfermask - Pack pio, mwdma and udma masks into xfer_mask
850  *	@pio_mask: pio_mask
851  *	@mwdma_mask: mwdma_mask
852  *	@udma_mask: udma_mask
853  *
854  *	Pack @pio_mask, @mwdma_mask and @udma_mask into a single
855  *	unsigned int xfer_mask.
856  *
857  *	LOCKING:
858  *	None.
859  *
860  *	RETURNS:
861  *	Packed xfer_mask.
862  */
863 unsigned long ata_pack_xfermask(unsigned long pio_mask,
864 				unsigned long mwdma_mask,
865 				unsigned long udma_mask)
866 {
867 	return ((pio_mask << ATA_SHIFT_PIO) & ATA_MASK_PIO) |
868 		((mwdma_mask << ATA_SHIFT_MWDMA) & ATA_MASK_MWDMA) |
869 		((udma_mask << ATA_SHIFT_UDMA) & ATA_MASK_UDMA);
870 }
871 
872 /**
873  *	ata_unpack_xfermask - Unpack xfer_mask into pio, mwdma and udma masks
874  *	@xfer_mask: xfer_mask to unpack
875  *	@pio_mask: resulting pio_mask
876  *	@mwdma_mask: resulting mwdma_mask
877  *	@udma_mask: resulting udma_mask
878  *
879  *	Unpack @xfer_mask into @pio_mask, @mwdma_mask and @udma_mask.
880  *	Any NULL distination masks will be ignored.
881  */
882 void ata_unpack_xfermask(unsigned long xfer_mask, unsigned long *pio_mask,
883 			 unsigned long *mwdma_mask, unsigned long *udma_mask)
884 {
885 	if (pio_mask)
886 		*pio_mask = (xfer_mask & ATA_MASK_PIO) >> ATA_SHIFT_PIO;
887 	if (mwdma_mask)
888 		*mwdma_mask = (xfer_mask & ATA_MASK_MWDMA) >> ATA_SHIFT_MWDMA;
889 	if (udma_mask)
890 		*udma_mask = (xfer_mask & ATA_MASK_UDMA) >> ATA_SHIFT_UDMA;
891 }
892 
893 static const struct ata_xfer_ent {
894 	int shift, bits;
895 	u8 base;
896 } ata_xfer_tbl[] = {
897 	{ ATA_SHIFT_PIO, ATA_NR_PIO_MODES, XFER_PIO_0 },
898 	{ ATA_SHIFT_MWDMA, ATA_NR_MWDMA_MODES, XFER_MW_DMA_0 },
899 	{ ATA_SHIFT_UDMA, ATA_NR_UDMA_MODES, XFER_UDMA_0 },
900 	{ -1, },
901 };
902 
903 /**
904  *	ata_xfer_mask2mode - Find matching XFER_* for the given xfer_mask
905  *	@xfer_mask: xfer_mask of interest
906  *
907  *	Return matching XFER_* value for @xfer_mask.  Only the highest
908  *	bit of @xfer_mask is considered.
909  *
910  *	LOCKING:
911  *	None.
912  *
913  *	RETURNS:
914  *	Matching XFER_* value, 0xff if no match found.
915  */
916 u8 ata_xfer_mask2mode(unsigned long xfer_mask)
917 {
918 	int highbit = fls(xfer_mask) - 1;
919 	const struct ata_xfer_ent *ent;
920 
921 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
922 		if (highbit >= ent->shift && highbit < ent->shift + ent->bits)
923 			return ent->base + highbit - ent->shift;
924 	return 0xff;
925 }
926 
927 /**
928  *	ata_xfer_mode2mask - Find matching xfer_mask for XFER_*
929  *	@xfer_mode: XFER_* of interest
930  *
931  *	Return matching xfer_mask for @xfer_mode.
932  *
933  *	LOCKING:
934  *	None.
935  *
936  *	RETURNS:
937  *	Matching xfer_mask, 0 if no match found.
938  */
939 unsigned long ata_xfer_mode2mask(u8 xfer_mode)
940 {
941 	const struct ata_xfer_ent *ent;
942 
943 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
944 		if (xfer_mode >= ent->base && xfer_mode < ent->base + ent->bits)
945 			return ((2 << (ent->shift + xfer_mode - ent->base)) - 1)
946 				& ~((1 << ent->shift) - 1);
947 	return 0;
948 }
949 
950 /**
951  *	ata_xfer_mode2shift - Find matching xfer_shift for XFER_*
952  *	@xfer_mode: XFER_* of interest
953  *
954  *	Return matching xfer_shift for @xfer_mode.
955  *
956  *	LOCKING:
957  *	None.
958  *
959  *	RETURNS:
960  *	Matching xfer_shift, -1 if no match found.
961  */
962 int ata_xfer_mode2shift(unsigned long xfer_mode)
963 {
964 	const struct ata_xfer_ent *ent;
965 
966 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
967 		if (xfer_mode >= ent->base && xfer_mode < ent->base + ent->bits)
968 			return ent->shift;
969 	return -1;
970 }
971 
972 /**
973  *	ata_mode_string - convert xfer_mask to string
974  *	@xfer_mask: mask of bits supported; only highest bit counts.
975  *
976  *	Determine string which represents the highest speed
977  *	(highest bit in @modemask).
978  *
979  *	LOCKING:
980  *	None.
981  *
982  *	RETURNS:
983  *	Constant C string representing highest speed listed in
984  *	@mode_mask, or the constant C string "<n/a>".
985  */
986 const char *ata_mode_string(unsigned long xfer_mask)
987 {
988 	static const char * const xfer_mode_str[] = {
989 		"PIO0",
990 		"PIO1",
991 		"PIO2",
992 		"PIO3",
993 		"PIO4",
994 		"PIO5",
995 		"PIO6",
996 		"MWDMA0",
997 		"MWDMA1",
998 		"MWDMA2",
999 		"MWDMA3",
1000 		"MWDMA4",
1001 		"UDMA/16",
1002 		"UDMA/25",
1003 		"UDMA/33",
1004 		"UDMA/44",
1005 		"UDMA/66",
1006 		"UDMA/100",
1007 		"UDMA/133",
1008 		"UDMA7",
1009 	};
1010 	int highbit;
1011 
1012 	highbit = fls(xfer_mask) - 1;
1013 	if (highbit >= 0 && highbit < ARRAY_SIZE(xfer_mode_str))
1014 		return xfer_mode_str[highbit];
1015 	return "<n/a>";
1016 }
1017 
1018 const char *sata_spd_string(unsigned int spd)
1019 {
1020 	static const char * const spd_str[] = {
1021 		"1.5 Gbps",
1022 		"3.0 Gbps",
1023 		"6.0 Gbps",
1024 	};
1025 
1026 	if (spd == 0 || (spd - 1) >= ARRAY_SIZE(spd_str))
1027 		return "<unknown>";
1028 	return spd_str[spd - 1];
1029 }
1030 
1031 /**
1032  *	ata_dev_classify - determine device type based on ATA-spec signature
1033  *	@tf: ATA taskfile register set for device to be identified
1034  *
1035  *	Determine from taskfile register contents whether a device is
1036  *	ATA or ATAPI, as per "Signature and persistence" section
1037  *	of ATA/PI spec (volume 1, sect 5.14).
1038  *
1039  *	LOCKING:
1040  *	None.
1041  *
1042  *	RETURNS:
1043  *	Device type, %ATA_DEV_ATA, %ATA_DEV_ATAPI, %ATA_DEV_PMP or
1044  *	%ATA_DEV_UNKNOWN the event of failure.
1045  */
1046 unsigned int ata_dev_classify(const struct ata_taskfile *tf)
1047 {
1048 	/* Apple's open source Darwin code hints that some devices only
1049 	 * put a proper signature into the LBA mid/high registers,
1050 	 * So, we only check those.  It's sufficient for uniqueness.
1051 	 *
1052 	 * ATA/ATAPI-7 (d1532v1r1: Feb. 19, 2003) specified separate
1053 	 * signatures for ATA and ATAPI devices attached on SerialATA,
1054 	 * 0x3c/0xc3 and 0x69/0x96 respectively.  However, SerialATA
1055 	 * spec has never mentioned about using different signatures
1056 	 * for ATA/ATAPI devices.  Then, Serial ATA II: Port
1057 	 * Multiplier specification began to use 0x69/0x96 to identify
1058 	 * port multpliers and 0x3c/0xc3 to identify SEMB device.
1059 	 * ATA/ATAPI-7 dropped descriptions about 0x3c/0xc3 and
1060 	 * 0x69/0x96 shortly and described them as reserved for
1061 	 * SerialATA.
1062 	 *
1063 	 * We follow the current spec and consider that 0x69/0x96
1064 	 * identifies a port multiplier and 0x3c/0xc3 a SEMB device.
1065 	 * Unfortunately, WDC WD1600JS-62MHB5 (a hard drive) reports
1066 	 * SEMB signature.  This is worked around in
1067 	 * ata_dev_read_id().
1068 	 */
1069 	if ((tf->lbam == 0) && (tf->lbah == 0)) {
1070 		DPRINTK("found ATA device by sig\n");
1071 		return ATA_DEV_ATA;
1072 	}
1073 
1074 	if ((tf->lbam == 0x14) && (tf->lbah == 0xeb)) {
1075 		DPRINTK("found ATAPI device by sig\n");
1076 		return ATA_DEV_ATAPI;
1077 	}
1078 
1079 	if ((tf->lbam == 0x69) && (tf->lbah == 0x96)) {
1080 		DPRINTK("found PMP device by sig\n");
1081 		return ATA_DEV_PMP;
1082 	}
1083 
1084 	if ((tf->lbam == 0x3c) && (tf->lbah == 0xc3)) {
1085 		DPRINTK("found SEMB device by sig (could be ATA device)\n");
1086 		return ATA_DEV_SEMB;
1087 	}
1088 
1089 	DPRINTK("unknown device\n");
1090 	return ATA_DEV_UNKNOWN;
1091 }
1092 
1093 /**
1094  *	ata_id_string - Convert IDENTIFY DEVICE page into string
1095  *	@id: IDENTIFY DEVICE results we will examine
1096  *	@s: string into which data is output
1097  *	@ofs: offset into identify device page
1098  *	@len: length of string to return. must be an even number.
1099  *
1100  *	The strings in the IDENTIFY DEVICE page are broken up into
1101  *	16-bit chunks.  Run through the string, and output each
1102  *	8-bit chunk linearly, regardless of platform.
1103  *
1104  *	LOCKING:
1105  *	caller.
1106  */
1107 
1108 void ata_id_string(const u16 *id, unsigned char *s,
1109 		   unsigned int ofs, unsigned int len)
1110 {
1111 	unsigned int c;
1112 
1113 	BUG_ON(len & 1);
1114 
1115 	while (len > 0) {
1116 		c = id[ofs] >> 8;
1117 		*s = c;
1118 		s++;
1119 
1120 		c = id[ofs] & 0xff;
1121 		*s = c;
1122 		s++;
1123 
1124 		ofs++;
1125 		len -= 2;
1126 	}
1127 }
1128 
1129 /**
1130  *	ata_id_c_string - Convert IDENTIFY DEVICE page into C string
1131  *	@id: IDENTIFY DEVICE results we will examine
1132  *	@s: string into which data is output
1133  *	@ofs: offset into identify device page
1134  *	@len: length of string to return. must be an odd number.
1135  *
1136  *	This function is identical to ata_id_string except that it
1137  *	trims trailing spaces and terminates the resulting string with
1138  *	null.  @len must be actual maximum length (even number) + 1.
1139  *
1140  *	LOCKING:
1141  *	caller.
1142  */
1143 void ata_id_c_string(const u16 *id, unsigned char *s,
1144 		     unsigned int ofs, unsigned int len)
1145 {
1146 	unsigned char *p;
1147 
1148 	ata_id_string(id, s, ofs, len - 1);
1149 
1150 	p = s + strnlen(s, len - 1);
1151 	while (p > s && p[-1] == ' ')
1152 		p--;
1153 	*p = '\0';
1154 }
1155 
1156 static u64 ata_id_n_sectors(const u16 *id)
1157 {
1158 	if (ata_id_has_lba(id)) {
1159 		if (ata_id_has_lba48(id))
1160 			return ata_id_u64(id, ATA_ID_LBA_CAPACITY_2);
1161 		else
1162 			return ata_id_u32(id, ATA_ID_LBA_CAPACITY);
1163 	} else {
1164 		if (ata_id_current_chs_valid(id))
1165 			return id[ATA_ID_CUR_CYLS] * id[ATA_ID_CUR_HEADS] *
1166 			       id[ATA_ID_CUR_SECTORS];
1167 		else
1168 			return id[ATA_ID_CYLS] * id[ATA_ID_HEADS] *
1169 			       id[ATA_ID_SECTORS];
1170 	}
1171 }
1172 
1173 u64 ata_tf_to_lba48(const struct ata_taskfile *tf)
1174 {
1175 	u64 sectors = 0;
1176 
1177 	sectors |= ((u64)(tf->hob_lbah & 0xff)) << 40;
1178 	sectors |= ((u64)(tf->hob_lbam & 0xff)) << 32;
1179 	sectors |= ((u64)(tf->hob_lbal & 0xff)) << 24;
1180 	sectors |= (tf->lbah & 0xff) << 16;
1181 	sectors |= (tf->lbam & 0xff) << 8;
1182 	sectors |= (tf->lbal & 0xff);
1183 
1184 	return sectors;
1185 }
1186 
1187 u64 ata_tf_to_lba(const struct ata_taskfile *tf)
1188 {
1189 	u64 sectors = 0;
1190 
1191 	sectors |= (tf->device & 0x0f) << 24;
1192 	sectors |= (tf->lbah & 0xff) << 16;
1193 	sectors |= (tf->lbam & 0xff) << 8;
1194 	sectors |= (tf->lbal & 0xff);
1195 
1196 	return sectors;
1197 }
1198 
1199 /**
1200  *	ata_read_native_max_address - Read native max address
1201  *	@dev: target device
1202  *	@max_sectors: out parameter for the result native max address
1203  *
1204  *	Perform an LBA48 or LBA28 native size query upon the device in
1205  *	question.
1206  *
1207  *	RETURNS:
1208  *	0 on success, -EACCES if command is aborted by the drive.
1209  *	-EIO on other errors.
1210  */
1211 static int ata_read_native_max_address(struct ata_device *dev, u64 *max_sectors)
1212 {
1213 	unsigned int err_mask;
1214 	struct ata_taskfile tf;
1215 	int lba48 = ata_id_has_lba48(dev->id);
1216 
1217 	ata_tf_init(dev, &tf);
1218 
1219 	/* always clear all address registers */
1220 	tf.flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
1221 
1222 	if (lba48) {
1223 		tf.command = ATA_CMD_READ_NATIVE_MAX_EXT;
1224 		tf.flags |= ATA_TFLAG_LBA48;
1225 	} else
1226 		tf.command = ATA_CMD_READ_NATIVE_MAX;
1227 
1228 	tf.protocol |= ATA_PROT_NODATA;
1229 	tf.device |= ATA_LBA;
1230 
1231 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
1232 	if (err_mask) {
1233 		ata_dev_printk(dev, KERN_WARNING, "failed to read native "
1234 			       "max address (err_mask=0x%x)\n", err_mask);
1235 		if (err_mask == AC_ERR_DEV && (tf.feature & ATA_ABORTED))
1236 			return -EACCES;
1237 		return -EIO;
1238 	}
1239 
1240 	if (lba48)
1241 		*max_sectors = ata_tf_to_lba48(&tf) + 1;
1242 	else
1243 		*max_sectors = ata_tf_to_lba(&tf) + 1;
1244 	if (dev->horkage & ATA_HORKAGE_HPA_SIZE)
1245 		(*max_sectors)--;
1246 	return 0;
1247 }
1248 
1249 /**
1250  *	ata_set_max_sectors - Set max sectors
1251  *	@dev: target device
1252  *	@new_sectors: new max sectors value to set for the device
1253  *
1254  *	Set max sectors of @dev to @new_sectors.
1255  *
1256  *	RETURNS:
1257  *	0 on success, -EACCES if command is aborted or denied (due to
1258  *	previous non-volatile SET_MAX) by the drive.  -EIO on other
1259  *	errors.
1260  */
1261 static int ata_set_max_sectors(struct ata_device *dev, u64 new_sectors)
1262 {
1263 	unsigned int err_mask;
1264 	struct ata_taskfile tf;
1265 	int lba48 = ata_id_has_lba48(dev->id);
1266 
1267 	new_sectors--;
1268 
1269 	ata_tf_init(dev, &tf);
1270 
1271 	tf.flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
1272 
1273 	if (lba48) {
1274 		tf.command = ATA_CMD_SET_MAX_EXT;
1275 		tf.flags |= ATA_TFLAG_LBA48;
1276 
1277 		tf.hob_lbal = (new_sectors >> 24) & 0xff;
1278 		tf.hob_lbam = (new_sectors >> 32) & 0xff;
1279 		tf.hob_lbah = (new_sectors >> 40) & 0xff;
1280 	} else {
1281 		tf.command = ATA_CMD_SET_MAX;
1282 
1283 		tf.device |= (new_sectors >> 24) & 0xf;
1284 	}
1285 
1286 	tf.protocol |= ATA_PROT_NODATA;
1287 	tf.device |= ATA_LBA;
1288 
1289 	tf.lbal = (new_sectors >> 0) & 0xff;
1290 	tf.lbam = (new_sectors >> 8) & 0xff;
1291 	tf.lbah = (new_sectors >> 16) & 0xff;
1292 
1293 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
1294 	if (err_mask) {
1295 		ata_dev_printk(dev, KERN_WARNING, "failed to set "
1296 			       "max address (err_mask=0x%x)\n", err_mask);
1297 		if (err_mask == AC_ERR_DEV &&
1298 		    (tf.feature & (ATA_ABORTED | ATA_IDNF)))
1299 			return -EACCES;
1300 		return -EIO;
1301 	}
1302 
1303 	return 0;
1304 }
1305 
1306 /**
1307  *	ata_hpa_resize		-	Resize a device with an HPA set
1308  *	@dev: Device to resize
1309  *
1310  *	Read the size of an LBA28 or LBA48 disk with HPA features and resize
1311  *	it if required to the full size of the media. The caller must check
1312  *	the drive has the HPA feature set enabled.
1313  *
1314  *	RETURNS:
1315  *	0 on success, -errno on failure.
1316  */
1317 static int ata_hpa_resize(struct ata_device *dev)
1318 {
1319 	struct ata_eh_context *ehc = &dev->link->eh_context;
1320 	int print_info = ehc->i.flags & ATA_EHI_PRINTINFO;
1321 	bool unlock_hpa = ata_ignore_hpa || dev->flags & ATA_DFLAG_UNLOCK_HPA;
1322 	u64 sectors = ata_id_n_sectors(dev->id);
1323 	u64 native_sectors;
1324 	int rc;
1325 
1326 	/* do we need to do it? */
1327 	if (dev->class != ATA_DEV_ATA ||
1328 	    !ata_id_has_lba(dev->id) || !ata_id_hpa_enabled(dev->id) ||
1329 	    (dev->horkage & ATA_HORKAGE_BROKEN_HPA))
1330 		return 0;
1331 
1332 	/* read native max address */
1333 	rc = ata_read_native_max_address(dev, &native_sectors);
1334 	if (rc) {
1335 		/* If device aborted the command or HPA isn't going to
1336 		 * be unlocked, skip HPA resizing.
1337 		 */
1338 		if (rc == -EACCES || !unlock_hpa) {
1339 			ata_dev_printk(dev, KERN_WARNING, "HPA support seems "
1340 				       "broken, skipping HPA handling\n");
1341 			dev->horkage |= ATA_HORKAGE_BROKEN_HPA;
1342 
1343 			/* we can continue if device aborted the command */
1344 			if (rc == -EACCES)
1345 				rc = 0;
1346 		}
1347 
1348 		return rc;
1349 	}
1350 	dev->n_native_sectors = native_sectors;
1351 
1352 	/* nothing to do? */
1353 	if (native_sectors <= sectors || !unlock_hpa) {
1354 		if (!print_info || native_sectors == sectors)
1355 			return 0;
1356 
1357 		if (native_sectors > sectors)
1358 			ata_dev_printk(dev, KERN_INFO,
1359 				"HPA detected: current %llu, native %llu\n",
1360 				(unsigned long long)sectors,
1361 				(unsigned long long)native_sectors);
1362 		else if (native_sectors < sectors)
1363 			ata_dev_printk(dev, KERN_WARNING,
1364 				"native sectors (%llu) is smaller than "
1365 				"sectors (%llu)\n",
1366 				(unsigned long long)native_sectors,
1367 				(unsigned long long)sectors);
1368 		return 0;
1369 	}
1370 
1371 	/* let's unlock HPA */
1372 	rc = ata_set_max_sectors(dev, native_sectors);
1373 	if (rc == -EACCES) {
1374 		/* if device aborted the command, skip HPA resizing */
1375 		ata_dev_printk(dev, KERN_WARNING, "device aborted resize "
1376 			       "(%llu -> %llu), skipping HPA handling\n",
1377 			       (unsigned long long)sectors,
1378 			       (unsigned long long)native_sectors);
1379 		dev->horkage |= ATA_HORKAGE_BROKEN_HPA;
1380 		return 0;
1381 	} else if (rc)
1382 		return rc;
1383 
1384 	/* re-read IDENTIFY data */
1385 	rc = ata_dev_reread_id(dev, 0);
1386 	if (rc) {
1387 		ata_dev_printk(dev, KERN_ERR, "failed to re-read IDENTIFY "
1388 			       "data after HPA resizing\n");
1389 		return rc;
1390 	}
1391 
1392 	if (print_info) {
1393 		u64 new_sectors = ata_id_n_sectors(dev->id);
1394 		ata_dev_printk(dev, KERN_INFO,
1395 			"HPA unlocked: %llu -> %llu, native %llu\n",
1396 			(unsigned long long)sectors,
1397 			(unsigned long long)new_sectors,
1398 			(unsigned long long)native_sectors);
1399 	}
1400 
1401 	return 0;
1402 }
1403 
1404 /**
1405  *	ata_dump_id - IDENTIFY DEVICE info debugging output
1406  *	@id: IDENTIFY DEVICE page to dump
1407  *
1408  *	Dump selected 16-bit words from the given IDENTIFY DEVICE
1409  *	page.
1410  *
1411  *	LOCKING:
1412  *	caller.
1413  */
1414 
1415 static inline void ata_dump_id(const u16 *id)
1416 {
1417 	DPRINTK("49==0x%04x  "
1418 		"53==0x%04x  "
1419 		"63==0x%04x  "
1420 		"64==0x%04x  "
1421 		"75==0x%04x  \n",
1422 		id[49],
1423 		id[53],
1424 		id[63],
1425 		id[64],
1426 		id[75]);
1427 	DPRINTK("80==0x%04x  "
1428 		"81==0x%04x  "
1429 		"82==0x%04x  "
1430 		"83==0x%04x  "
1431 		"84==0x%04x  \n",
1432 		id[80],
1433 		id[81],
1434 		id[82],
1435 		id[83],
1436 		id[84]);
1437 	DPRINTK("88==0x%04x  "
1438 		"93==0x%04x\n",
1439 		id[88],
1440 		id[93]);
1441 }
1442 
1443 /**
1444  *	ata_id_xfermask - Compute xfermask from the given IDENTIFY data
1445  *	@id: IDENTIFY data to compute xfer mask from
1446  *
1447  *	Compute the xfermask for this device. This is not as trivial
1448  *	as it seems if we must consider early devices correctly.
1449  *
1450  *	FIXME: pre IDE drive timing (do we care ?).
1451  *
1452  *	LOCKING:
1453  *	None.
1454  *
1455  *	RETURNS:
1456  *	Computed xfermask
1457  */
1458 unsigned long ata_id_xfermask(const u16 *id)
1459 {
1460 	unsigned long pio_mask, mwdma_mask, udma_mask;
1461 
1462 	/* Usual case. Word 53 indicates word 64 is valid */
1463 	if (id[ATA_ID_FIELD_VALID] & (1 << 1)) {
1464 		pio_mask = id[ATA_ID_PIO_MODES] & 0x03;
1465 		pio_mask <<= 3;
1466 		pio_mask |= 0x7;
1467 	} else {
1468 		/* If word 64 isn't valid then Word 51 high byte holds
1469 		 * the PIO timing number for the maximum. Turn it into
1470 		 * a mask.
1471 		 */
1472 		u8 mode = (id[ATA_ID_OLD_PIO_MODES] >> 8) & 0xFF;
1473 		if (mode < 5)	/* Valid PIO range */
1474 			pio_mask = (2 << mode) - 1;
1475 		else
1476 			pio_mask = 1;
1477 
1478 		/* But wait.. there's more. Design your standards by
1479 		 * committee and you too can get a free iordy field to
1480 		 * process. However its the speeds not the modes that
1481 		 * are supported... Note drivers using the timing API
1482 		 * will get this right anyway
1483 		 */
1484 	}
1485 
1486 	mwdma_mask = id[ATA_ID_MWDMA_MODES] & 0x07;
1487 
1488 	if (ata_id_is_cfa(id)) {
1489 		/*
1490 		 *	Process compact flash extended modes
1491 		 */
1492 		int pio = (id[ATA_ID_CFA_MODES] >> 0) & 0x7;
1493 		int dma = (id[ATA_ID_CFA_MODES] >> 3) & 0x7;
1494 
1495 		if (pio)
1496 			pio_mask |= (1 << 5);
1497 		if (pio > 1)
1498 			pio_mask |= (1 << 6);
1499 		if (dma)
1500 			mwdma_mask |= (1 << 3);
1501 		if (dma > 1)
1502 			mwdma_mask |= (1 << 4);
1503 	}
1504 
1505 	udma_mask = 0;
1506 	if (id[ATA_ID_FIELD_VALID] & (1 << 2))
1507 		udma_mask = id[ATA_ID_UDMA_MODES] & 0xff;
1508 
1509 	return ata_pack_xfermask(pio_mask, mwdma_mask, udma_mask);
1510 }
1511 
1512 static void ata_qc_complete_internal(struct ata_queued_cmd *qc)
1513 {
1514 	struct completion *waiting = qc->private_data;
1515 
1516 	complete(waiting);
1517 }
1518 
1519 /**
1520  *	ata_exec_internal_sg - execute libata internal command
1521  *	@dev: Device to which the command is sent
1522  *	@tf: Taskfile registers for the command and the result
1523  *	@cdb: CDB for packet command
1524  *	@dma_dir: Data tranfer direction of the command
1525  *	@sgl: sg list for the data buffer of the command
1526  *	@n_elem: Number of sg entries
1527  *	@timeout: Timeout in msecs (0 for default)
1528  *
1529  *	Executes libata internal command with timeout.  @tf contains
1530  *	command on entry and result on return.  Timeout and error
1531  *	conditions are reported via return value.  No recovery action
1532  *	is taken after a command times out.  It's caller's duty to
1533  *	clean up after timeout.
1534  *
1535  *	LOCKING:
1536  *	None.  Should be called with kernel context, might sleep.
1537  *
1538  *	RETURNS:
1539  *	Zero on success, AC_ERR_* mask on failure
1540  */
1541 unsigned ata_exec_internal_sg(struct ata_device *dev,
1542 			      struct ata_taskfile *tf, const u8 *cdb,
1543 			      int dma_dir, struct scatterlist *sgl,
1544 			      unsigned int n_elem, unsigned long timeout)
1545 {
1546 	struct ata_link *link = dev->link;
1547 	struct ata_port *ap = link->ap;
1548 	u8 command = tf->command;
1549 	int auto_timeout = 0;
1550 	struct ata_queued_cmd *qc;
1551 	unsigned int tag, preempted_tag;
1552 	u32 preempted_sactive, preempted_qc_active;
1553 	int preempted_nr_active_links;
1554 	DECLARE_COMPLETION_ONSTACK(wait);
1555 	unsigned long flags;
1556 	unsigned int err_mask;
1557 	int rc;
1558 
1559 	spin_lock_irqsave(ap->lock, flags);
1560 
1561 	/* no internal command while frozen */
1562 	if (ap->pflags & ATA_PFLAG_FROZEN) {
1563 		spin_unlock_irqrestore(ap->lock, flags);
1564 		return AC_ERR_SYSTEM;
1565 	}
1566 
1567 	/* initialize internal qc */
1568 
1569 	/* XXX: Tag 0 is used for drivers with legacy EH as some
1570 	 * drivers choke if any other tag is given.  This breaks
1571 	 * ata_tag_internal() test for those drivers.  Don't use new
1572 	 * EH stuff without converting to it.
1573 	 */
1574 	if (ap->ops->error_handler)
1575 		tag = ATA_TAG_INTERNAL;
1576 	else
1577 		tag = 0;
1578 
1579 	if (test_and_set_bit(tag, &ap->qc_allocated))
1580 		BUG();
1581 	qc = __ata_qc_from_tag(ap, tag);
1582 
1583 	qc->tag = tag;
1584 	qc->scsicmd = NULL;
1585 	qc->ap = ap;
1586 	qc->dev = dev;
1587 	ata_qc_reinit(qc);
1588 
1589 	preempted_tag = link->active_tag;
1590 	preempted_sactive = link->sactive;
1591 	preempted_qc_active = ap->qc_active;
1592 	preempted_nr_active_links = ap->nr_active_links;
1593 	link->active_tag = ATA_TAG_POISON;
1594 	link->sactive = 0;
1595 	ap->qc_active = 0;
1596 	ap->nr_active_links = 0;
1597 
1598 	/* prepare & issue qc */
1599 	qc->tf = *tf;
1600 	if (cdb)
1601 		memcpy(qc->cdb, cdb, ATAPI_CDB_LEN);
1602 	qc->flags |= ATA_QCFLAG_RESULT_TF;
1603 	qc->dma_dir = dma_dir;
1604 	if (dma_dir != DMA_NONE) {
1605 		unsigned int i, buflen = 0;
1606 		struct scatterlist *sg;
1607 
1608 		for_each_sg(sgl, sg, n_elem, i)
1609 			buflen += sg->length;
1610 
1611 		ata_sg_init(qc, sgl, n_elem);
1612 		qc->nbytes = buflen;
1613 	}
1614 
1615 	qc->private_data = &wait;
1616 	qc->complete_fn = ata_qc_complete_internal;
1617 
1618 	ata_qc_issue(qc);
1619 
1620 	spin_unlock_irqrestore(ap->lock, flags);
1621 
1622 	if (!timeout) {
1623 		if (ata_probe_timeout)
1624 			timeout = ata_probe_timeout * 1000;
1625 		else {
1626 			timeout = ata_internal_cmd_timeout(dev, command);
1627 			auto_timeout = 1;
1628 		}
1629 	}
1630 
1631 	if (ap->ops->error_handler)
1632 		ata_eh_release(ap);
1633 
1634 	rc = wait_for_completion_timeout(&wait, msecs_to_jiffies(timeout));
1635 
1636 	if (ap->ops->error_handler)
1637 		ata_eh_acquire(ap);
1638 
1639 	ata_sff_flush_pio_task(ap);
1640 
1641 	if (!rc) {
1642 		spin_lock_irqsave(ap->lock, flags);
1643 
1644 		/* We're racing with irq here.  If we lose, the
1645 		 * following test prevents us from completing the qc
1646 		 * twice.  If we win, the port is frozen and will be
1647 		 * cleaned up by ->post_internal_cmd().
1648 		 */
1649 		if (qc->flags & ATA_QCFLAG_ACTIVE) {
1650 			qc->err_mask |= AC_ERR_TIMEOUT;
1651 
1652 			if (ap->ops->error_handler)
1653 				ata_port_freeze(ap);
1654 			else
1655 				ata_qc_complete(qc);
1656 
1657 			if (ata_msg_warn(ap))
1658 				ata_dev_printk(dev, KERN_WARNING,
1659 					"qc timeout (cmd 0x%x)\n", command);
1660 		}
1661 
1662 		spin_unlock_irqrestore(ap->lock, flags);
1663 	}
1664 
1665 	/* do post_internal_cmd */
1666 	if (ap->ops->post_internal_cmd)
1667 		ap->ops->post_internal_cmd(qc);
1668 
1669 	/* perform minimal error analysis */
1670 	if (qc->flags & ATA_QCFLAG_FAILED) {
1671 		if (qc->result_tf.command & (ATA_ERR | ATA_DF))
1672 			qc->err_mask |= AC_ERR_DEV;
1673 
1674 		if (!qc->err_mask)
1675 			qc->err_mask |= AC_ERR_OTHER;
1676 
1677 		if (qc->err_mask & ~AC_ERR_OTHER)
1678 			qc->err_mask &= ~AC_ERR_OTHER;
1679 	}
1680 
1681 	/* finish up */
1682 	spin_lock_irqsave(ap->lock, flags);
1683 
1684 	*tf = qc->result_tf;
1685 	err_mask = qc->err_mask;
1686 
1687 	ata_qc_free(qc);
1688 	link->active_tag = preempted_tag;
1689 	link->sactive = preempted_sactive;
1690 	ap->qc_active = preempted_qc_active;
1691 	ap->nr_active_links = preempted_nr_active_links;
1692 
1693 	spin_unlock_irqrestore(ap->lock, flags);
1694 
1695 	if ((err_mask & AC_ERR_TIMEOUT) && auto_timeout)
1696 		ata_internal_cmd_timed_out(dev, command);
1697 
1698 	return err_mask;
1699 }
1700 
1701 /**
1702  *	ata_exec_internal - execute libata internal command
1703  *	@dev: Device to which the command is sent
1704  *	@tf: Taskfile registers for the command and the result
1705  *	@cdb: CDB for packet command
1706  *	@dma_dir: Data tranfer direction of the command
1707  *	@buf: Data buffer of the command
1708  *	@buflen: Length of data buffer
1709  *	@timeout: Timeout in msecs (0 for default)
1710  *
1711  *	Wrapper around ata_exec_internal_sg() which takes simple
1712  *	buffer instead of sg list.
1713  *
1714  *	LOCKING:
1715  *	None.  Should be called with kernel context, might sleep.
1716  *
1717  *	RETURNS:
1718  *	Zero on success, AC_ERR_* mask on failure
1719  */
1720 unsigned ata_exec_internal(struct ata_device *dev,
1721 			   struct ata_taskfile *tf, const u8 *cdb,
1722 			   int dma_dir, void *buf, unsigned int buflen,
1723 			   unsigned long timeout)
1724 {
1725 	struct scatterlist *psg = NULL, sg;
1726 	unsigned int n_elem = 0;
1727 
1728 	if (dma_dir != DMA_NONE) {
1729 		WARN_ON(!buf);
1730 		sg_init_one(&sg, buf, buflen);
1731 		psg = &sg;
1732 		n_elem++;
1733 	}
1734 
1735 	return ata_exec_internal_sg(dev, tf, cdb, dma_dir, psg, n_elem,
1736 				    timeout);
1737 }
1738 
1739 /**
1740  *	ata_do_simple_cmd - execute simple internal command
1741  *	@dev: Device to which the command is sent
1742  *	@cmd: Opcode to execute
1743  *
1744  *	Execute a 'simple' command, that only consists of the opcode
1745  *	'cmd' itself, without filling any other registers
1746  *
1747  *	LOCKING:
1748  *	Kernel thread context (may sleep).
1749  *
1750  *	RETURNS:
1751  *	Zero on success, AC_ERR_* mask on failure
1752  */
1753 unsigned int ata_do_simple_cmd(struct ata_device *dev, u8 cmd)
1754 {
1755 	struct ata_taskfile tf;
1756 
1757 	ata_tf_init(dev, &tf);
1758 
1759 	tf.command = cmd;
1760 	tf.flags |= ATA_TFLAG_DEVICE;
1761 	tf.protocol = ATA_PROT_NODATA;
1762 
1763 	return ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
1764 }
1765 
1766 /**
1767  *	ata_pio_need_iordy	-	check if iordy needed
1768  *	@adev: ATA device
1769  *
1770  *	Check if the current speed of the device requires IORDY. Used
1771  *	by various controllers for chip configuration.
1772  */
1773 unsigned int ata_pio_need_iordy(const struct ata_device *adev)
1774 {
1775 	/* Don't set IORDY if we're preparing for reset.  IORDY may
1776 	 * lead to controller lock up on certain controllers if the
1777 	 * port is not occupied.  See bko#11703 for details.
1778 	 */
1779 	if (adev->link->ap->pflags & ATA_PFLAG_RESETTING)
1780 		return 0;
1781 	/* Controller doesn't support IORDY.  Probably a pointless
1782 	 * check as the caller should know this.
1783 	 */
1784 	if (adev->link->ap->flags & ATA_FLAG_NO_IORDY)
1785 		return 0;
1786 	/* CF spec. r4.1 Table 22 says no iordy on PIO5 and PIO6.  */
1787 	if (ata_id_is_cfa(adev->id)
1788 	    && (adev->pio_mode == XFER_PIO_5 || adev->pio_mode == XFER_PIO_6))
1789 		return 0;
1790 	/* PIO3 and higher it is mandatory */
1791 	if (adev->pio_mode > XFER_PIO_2)
1792 		return 1;
1793 	/* We turn it on when possible */
1794 	if (ata_id_has_iordy(adev->id))
1795 		return 1;
1796 	return 0;
1797 }
1798 
1799 /**
1800  *	ata_pio_mask_no_iordy	-	Return the non IORDY mask
1801  *	@adev: ATA device
1802  *
1803  *	Compute the highest mode possible if we are not using iordy. Return
1804  *	-1 if no iordy mode is available.
1805  */
1806 static u32 ata_pio_mask_no_iordy(const struct ata_device *adev)
1807 {
1808 	/* If we have no drive specific rule, then PIO 2 is non IORDY */
1809 	if (adev->id[ATA_ID_FIELD_VALID] & 2) {	/* EIDE */
1810 		u16 pio = adev->id[ATA_ID_EIDE_PIO];
1811 		/* Is the speed faster than the drive allows non IORDY ? */
1812 		if (pio) {
1813 			/* This is cycle times not frequency - watch the logic! */
1814 			if (pio > 240)	/* PIO2 is 240nS per cycle */
1815 				return 3 << ATA_SHIFT_PIO;
1816 			return 7 << ATA_SHIFT_PIO;
1817 		}
1818 	}
1819 	return 3 << ATA_SHIFT_PIO;
1820 }
1821 
1822 /**
1823  *	ata_do_dev_read_id		-	default ID read method
1824  *	@dev: device
1825  *	@tf: proposed taskfile
1826  *	@id: data buffer
1827  *
1828  *	Issue the identify taskfile and hand back the buffer containing
1829  *	identify data. For some RAID controllers and for pre ATA devices
1830  *	this function is wrapped or replaced by the driver
1831  */
1832 unsigned int ata_do_dev_read_id(struct ata_device *dev,
1833 					struct ata_taskfile *tf, u16 *id)
1834 {
1835 	return ata_exec_internal(dev, tf, NULL, DMA_FROM_DEVICE,
1836 				     id, sizeof(id[0]) * ATA_ID_WORDS, 0);
1837 }
1838 
1839 /**
1840  *	ata_dev_read_id - Read ID data from the specified device
1841  *	@dev: target device
1842  *	@p_class: pointer to class of the target device (may be changed)
1843  *	@flags: ATA_READID_* flags
1844  *	@id: buffer to read IDENTIFY data into
1845  *
1846  *	Read ID data from the specified device.  ATA_CMD_ID_ATA is
1847  *	performed on ATA devices and ATA_CMD_ID_ATAPI on ATAPI
1848  *	devices.  This function also issues ATA_CMD_INIT_DEV_PARAMS
1849  *	for pre-ATA4 drives.
1850  *
1851  *	FIXME: ATA_CMD_ID_ATA is optional for early drives and right
1852  *	now we abort if we hit that case.
1853  *
1854  *	LOCKING:
1855  *	Kernel thread context (may sleep)
1856  *
1857  *	RETURNS:
1858  *	0 on success, -errno otherwise.
1859  */
1860 int ata_dev_read_id(struct ata_device *dev, unsigned int *p_class,
1861 		    unsigned int flags, u16 *id)
1862 {
1863 	struct ata_port *ap = dev->link->ap;
1864 	unsigned int class = *p_class;
1865 	struct ata_taskfile tf;
1866 	unsigned int err_mask = 0;
1867 	const char *reason;
1868 	bool is_semb = class == ATA_DEV_SEMB;
1869 	int may_fallback = 1, tried_spinup = 0;
1870 	int rc;
1871 
1872 	if (ata_msg_ctl(ap))
1873 		ata_dev_printk(dev, KERN_DEBUG, "%s: ENTER\n", __func__);
1874 
1875 retry:
1876 	ata_tf_init(dev, &tf);
1877 
1878 	switch (class) {
1879 	case ATA_DEV_SEMB:
1880 		class = ATA_DEV_ATA;	/* some hard drives report SEMB sig */
1881 	case ATA_DEV_ATA:
1882 		tf.command = ATA_CMD_ID_ATA;
1883 		break;
1884 	case ATA_DEV_ATAPI:
1885 		tf.command = ATA_CMD_ID_ATAPI;
1886 		break;
1887 	default:
1888 		rc = -ENODEV;
1889 		reason = "unsupported class";
1890 		goto err_out;
1891 	}
1892 
1893 	tf.protocol = ATA_PROT_PIO;
1894 
1895 	/* Some devices choke if TF registers contain garbage.  Make
1896 	 * sure those are properly initialized.
1897 	 */
1898 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1899 
1900 	/* Device presence detection is unreliable on some
1901 	 * controllers.  Always poll IDENTIFY if available.
1902 	 */
1903 	tf.flags |= ATA_TFLAG_POLLING;
1904 
1905 	if (ap->ops->read_id)
1906 		err_mask = ap->ops->read_id(dev, &tf, id);
1907 	else
1908 		err_mask = ata_do_dev_read_id(dev, &tf, id);
1909 
1910 	if (err_mask) {
1911 		if (err_mask & AC_ERR_NODEV_HINT) {
1912 			ata_dev_printk(dev, KERN_DEBUG,
1913 				       "NODEV after polling detection\n");
1914 			return -ENOENT;
1915 		}
1916 
1917 		if (is_semb) {
1918 			ata_dev_printk(dev, KERN_INFO, "IDENTIFY failed on "
1919 				       "device w/ SEMB sig, disabled\n");
1920 			/* SEMB is not supported yet */
1921 			*p_class = ATA_DEV_SEMB_UNSUP;
1922 			return 0;
1923 		}
1924 
1925 		if ((err_mask == AC_ERR_DEV) && (tf.feature & ATA_ABORTED)) {
1926 			/* Device or controller might have reported
1927 			 * the wrong device class.  Give a shot at the
1928 			 * other IDENTIFY if the current one is
1929 			 * aborted by the device.
1930 			 */
1931 			if (may_fallback) {
1932 				may_fallback = 0;
1933 
1934 				if (class == ATA_DEV_ATA)
1935 					class = ATA_DEV_ATAPI;
1936 				else
1937 					class = ATA_DEV_ATA;
1938 				goto retry;
1939 			}
1940 
1941 			/* Control reaches here iff the device aborted
1942 			 * both flavors of IDENTIFYs which happens
1943 			 * sometimes with phantom devices.
1944 			 */
1945 			ata_dev_printk(dev, KERN_DEBUG,
1946 				       "both IDENTIFYs aborted, assuming NODEV\n");
1947 			return -ENOENT;
1948 		}
1949 
1950 		rc = -EIO;
1951 		reason = "I/O error";
1952 		goto err_out;
1953 	}
1954 
1955 	if (dev->horkage & ATA_HORKAGE_DUMP_ID) {
1956 		ata_dev_printk(dev, KERN_DEBUG, "dumping IDENTIFY data, "
1957 			       "class=%d may_fallback=%d tried_spinup=%d\n",
1958 			       class, may_fallback, tried_spinup);
1959 		print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET,
1960 			       16, 2, id, ATA_ID_WORDS * sizeof(*id), true);
1961 	}
1962 
1963 	/* Falling back doesn't make sense if ID data was read
1964 	 * successfully at least once.
1965 	 */
1966 	may_fallback = 0;
1967 
1968 	swap_buf_le16(id, ATA_ID_WORDS);
1969 
1970 	/* sanity check */
1971 	rc = -EINVAL;
1972 	reason = "device reports invalid type";
1973 
1974 	if (class == ATA_DEV_ATA) {
1975 		if (!ata_id_is_ata(id) && !ata_id_is_cfa(id))
1976 			goto err_out;
1977 	} else {
1978 		if (ata_id_is_ata(id))
1979 			goto err_out;
1980 	}
1981 
1982 	if (!tried_spinup && (id[2] == 0x37c8 || id[2] == 0x738c)) {
1983 		tried_spinup = 1;
1984 		/*
1985 		 * Drive powered-up in standby mode, and requires a specific
1986 		 * SET_FEATURES spin-up subcommand before it will accept
1987 		 * anything other than the original IDENTIFY command.
1988 		 */
1989 		err_mask = ata_dev_set_feature(dev, SETFEATURES_SPINUP, 0);
1990 		if (err_mask && id[2] != 0x738c) {
1991 			rc = -EIO;
1992 			reason = "SPINUP failed";
1993 			goto err_out;
1994 		}
1995 		/*
1996 		 * If the drive initially returned incomplete IDENTIFY info,
1997 		 * we now must reissue the IDENTIFY command.
1998 		 */
1999 		if (id[2] == 0x37c8)
2000 			goto retry;
2001 	}
2002 
2003 	if ((flags & ATA_READID_POSTRESET) && class == ATA_DEV_ATA) {
2004 		/*
2005 		 * The exact sequence expected by certain pre-ATA4 drives is:
2006 		 * SRST RESET
2007 		 * IDENTIFY (optional in early ATA)
2008 		 * INITIALIZE DEVICE PARAMETERS (later IDE and ATA)
2009 		 * anything else..
2010 		 * Some drives were very specific about that exact sequence.
2011 		 *
2012 		 * Note that ATA4 says lba is mandatory so the second check
2013 		 * should never trigger.
2014 		 */
2015 		if (ata_id_major_version(id) < 4 || !ata_id_has_lba(id)) {
2016 			err_mask = ata_dev_init_params(dev, id[3], id[6]);
2017 			if (err_mask) {
2018 				rc = -EIO;
2019 				reason = "INIT_DEV_PARAMS failed";
2020 				goto err_out;
2021 			}
2022 
2023 			/* current CHS translation info (id[53-58]) might be
2024 			 * changed. reread the identify device info.
2025 			 */
2026 			flags &= ~ATA_READID_POSTRESET;
2027 			goto retry;
2028 		}
2029 	}
2030 
2031 	*p_class = class;
2032 
2033 	return 0;
2034 
2035  err_out:
2036 	if (ata_msg_warn(ap))
2037 		ata_dev_printk(dev, KERN_WARNING, "failed to IDENTIFY "
2038 			       "(%s, err_mask=0x%x)\n", reason, err_mask);
2039 	return rc;
2040 }
2041 
2042 static int ata_do_link_spd_horkage(struct ata_device *dev)
2043 {
2044 	struct ata_link *plink = ata_dev_phys_link(dev);
2045 	u32 target, target_limit;
2046 
2047 	if (!sata_scr_valid(plink))
2048 		return 0;
2049 
2050 	if (dev->horkage & ATA_HORKAGE_1_5_GBPS)
2051 		target = 1;
2052 	else
2053 		return 0;
2054 
2055 	target_limit = (1 << target) - 1;
2056 
2057 	/* if already on stricter limit, no need to push further */
2058 	if (plink->sata_spd_limit <= target_limit)
2059 		return 0;
2060 
2061 	plink->sata_spd_limit = target_limit;
2062 
2063 	/* Request another EH round by returning -EAGAIN if link is
2064 	 * going faster than the target speed.  Forward progress is
2065 	 * guaranteed by setting sata_spd_limit to target_limit above.
2066 	 */
2067 	if (plink->sata_spd > target) {
2068 		ata_dev_printk(dev, KERN_INFO,
2069 			       "applying link speed limit horkage to %s\n",
2070 			       sata_spd_string(target));
2071 		return -EAGAIN;
2072 	}
2073 	return 0;
2074 }
2075 
2076 static inline u8 ata_dev_knobble(struct ata_device *dev)
2077 {
2078 	struct ata_port *ap = dev->link->ap;
2079 
2080 	if (ata_dev_blacklisted(dev) & ATA_HORKAGE_BRIDGE_OK)
2081 		return 0;
2082 
2083 	return ((ap->cbl == ATA_CBL_SATA) && (!ata_id_is_sata(dev->id)));
2084 }
2085 
2086 static int ata_dev_config_ncq(struct ata_device *dev,
2087 			       char *desc, size_t desc_sz)
2088 {
2089 	struct ata_port *ap = dev->link->ap;
2090 	int hdepth = 0, ddepth = ata_id_queue_depth(dev->id);
2091 	unsigned int err_mask;
2092 	char *aa_desc = "";
2093 
2094 	if (!ata_id_has_ncq(dev->id)) {
2095 		desc[0] = '\0';
2096 		return 0;
2097 	}
2098 	if (dev->horkage & ATA_HORKAGE_NONCQ) {
2099 		snprintf(desc, desc_sz, "NCQ (not used)");
2100 		return 0;
2101 	}
2102 	if (ap->flags & ATA_FLAG_NCQ) {
2103 		hdepth = min(ap->scsi_host->can_queue, ATA_MAX_QUEUE - 1);
2104 		dev->flags |= ATA_DFLAG_NCQ;
2105 	}
2106 
2107 	if (!(dev->horkage & ATA_HORKAGE_BROKEN_FPDMA_AA) &&
2108 		(ap->flags & ATA_FLAG_FPDMA_AA) &&
2109 		ata_id_has_fpdma_aa(dev->id)) {
2110 		err_mask = ata_dev_set_feature(dev, SETFEATURES_SATA_ENABLE,
2111 			SATA_FPDMA_AA);
2112 		if (err_mask) {
2113 			ata_dev_printk(dev, KERN_ERR, "failed to enable AA"
2114 				"(error_mask=0x%x)\n", err_mask);
2115 			if (err_mask != AC_ERR_DEV) {
2116 				dev->horkage |= ATA_HORKAGE_BROKEN_FPDMA_AA;
2117 				return -EIO;
2118 			}
2119 		} else
2120 			aa_desc = ", AA";
2121 	}
2122 
2123 	if (hdepth >= ddepth)
2124 		snprintf(desc, desc_sz, "NCQ (depth %d)%s", ddepth, aa_desc);
2125 	else
2126 		snprintf(desc, desc_sz, "NCQ (depth %d/%d)%s", hdepth,
2127 			ddepth, aa_desc);
2128 	return 0;
2129 }
2130 
2131 /**
2132  *	ata_dev_configure - Configure the specified ATA/ATAPI device
2133  *	@dev: Target device to configure
2134  *
2135  *	Configure @dev according to @dev->id.  Generic and low-level
2136  *	driver specific fixups are also applied.
2137  *
2138  *	LOCKING:
2139  *	Kernel thread context (may sleep)
2140  *
2141  *	RETURNS:
2142  *	0 on success, -errno otherwise
2143  */
2144 int ata_dev_configure(struct ata_device *dev)
2145 {
2146 	struct ata_port *ap = dev->link->ap;
2147 	struct ata_eh_context *ehc = &dev->link->eh_context;
2148 	int print_info = ehc->i.flags & ATA_EHI_PRINTINFO;
2149 	const u16 *id = dev->id;
2150 	unsigned long xfer_mask;
2151 	char revbuf[7];		/* XYZ-99\0 */
2152 	char fwrevbuf[ATA_ID_FW_REV_LEN+1];
2153 	char modelbuf[ATA_ID_PROD_LEN+1];
2154 	int rc;
2155 
2156 	if (!ata_dev_enabled(dev) && ata_msg_info(ap)) {
2157 		ata_dev_printk(dev, KERN_INFO, "%s: ENTER/EXIT -- nodev\n",
2158 			       __func__);
2159 		return 0;
2160 	}
2161 
2162 	if (ata_msg_probe(ap))
2163 		ata_dev_printk(dev, KERN_DEBUG, "%s: ENTER\n", __func__);
2164 
2165 	/* set horkage */
2166 	dev->horkage |= ata_dev_blacklisted(dev);
2167 	ata_force_horkage(dev);
2168 
2169 	if (dev->horkage & ATA_HORKAGE_DISABLE) {
2170 		ata_dev_printk(dev, KERN_INFO,
2171 			       "unsupported device, disabling\n");
2172 		ata_dev_disable(dev);
2173 		return 0;
2174 	}
2175 
2176 	if ((!atapi_enabled || (ap->flags & ATA_FLAG_NO_ATAPI)) &&
2177 	    dev->class == ATA_DEV_ATAPI) {
2178 		ata_dev_printk(dev, KERN_WARNING,
2179 			"WARNING: ATAPI is %s, device ignored.\n",
2180 			atapi_enabled ? "not supported with this driver"
2181 				      : "disabled");
2182 		ata_dev_disable(dev);
2183 		return 0;
2184 	}
2185 
2186 	rc = ata_do_link_spd_horkage(dev);
2187 	if (rc)
2188 		return rc;
2189 
2190 	/* let ACPI work its magic */
2191 	rc = ata_acpi_on_devcfg(dev);
2192 	if (rc)
2193 		return rc;
2194 
2195 	/* massage HPA, do it early as it might change IDENTIFY data */
2196 	rc = ata_hpa_resize(dev);
2197 	if (rc)
2198 		return rc;
2199 
2200 	/* print device capabilities */
2201 	if (ata_msg_probe(ap))
2202 		ata_dev_printk(dev, KERN_DEBUG,
2203 			       "%s: cfg 49:%04x 82:%04x 83:%04x 84:%04x "
2204 			       "85:%04x 86:%04x 87:%04x 88:%04x\n",
2205 			       __func__,
2206 			       id[49], id[82], id[83], id[84],
2207 			       id[85], id[86], id[87], id[88]);
2208 
2209 	/* initialize to-be-configured parameters */
2210 	dev->flags &= ~ATA_DFLAG_CFG_MASK;
2211 	dev->max_sectors = 0;
2212 	dev->cdb_len = 0;
2213 	dev->n_sectors = 0;
2214 	dev->cylinders = 0;
2215 	dev->heads = 0;
2216 	dev->sectors = 0;
2217 	dev->multi_count = 0;
2218 
2219 	/*
2220 	 * common ATA, ATAPI feature tests
2221 	 */
2222 
2223 	/* find max transfer mode; for printk only */
2224 	xfer_mask = ata_id_xfermask(id);
2225 
2226 	if (ata_msg_probe(ap))
2227 		ata_dump_id(id);
2228 
2229 	/* SCSI only uses 4-char revisions, dump full 8 chars from ATA */
2230 	ata_id_c_string(dev->id, fwrevbuf, ATA_ID_FW_REV,
2231 			sizeof(fwrevbuf));
2232 
2233 	ata_id_c_string(dev->id, modelbuf, ATA_ID_PROD,
2234 			sizeof(modelbuf));
2235 
2236 	/* ATA-specific feature tests */
2237 	if (dev->class == ATA_DEV_ATA) {
2238 		if (ata_id_is_cfa(id)) {
2239 			/* CPRM may make this media unusable */
2240 			if (id[ATA_ID_CFA_KEY_MGMT] & 1)
2241 				ata_dev_printk(dev, KERN_WARNING,
2242 					       "supports DRM functions and may "
2243 					       "not be fully accessible.\n");
2244 			snprintf(revbuf, 7, "CFA");
2245 		} else {
2246 			snprintf(revbuf, 7, "ATA-%d", ata_id_major_version(id));
2247 			/* Warn the user if the device has TPM extensions */
2248 			if (ata_id_has_tpm(id))
2249 				ata_dev_printk(dev, KERN_WARNING,
2250 					       "supports DRM functions and may "
2251 					       "not be fully accessible.\n");
2252 		}
2253 
2254 		dev->n_sectors = ata_id_n_sectors(id);
2255 
2256 		/* get current R/W Multiple count setting */
2257 		if ((dev->id[47] >> 8) == 0x80 && (dev->id[59] & 0x100)) {
2258 			unsigned int max = dev->id[47] & 0xff;
2259 			unsigned int cnt = dev->id[59] & 0xff;
2260 			/* only recognize/allow powers of two here */
2261 			if (is_power_of_2(max) && is_power_of_2(cnt))
2262 				if (cnt <= max)
2263 					dev->multi_count = cnt;
2264 		}
2265 
2266 		if (ata_id_has_lba(id)) {
2267 			const char *lba_desc;
2268 			char ncq_desc[24];
2269 
2270 			lba_desc = "LBA";
2271 			dev->flags |= ATA_DFLAG_LBA;
2272 			if (ata_id_has_lba48(id)) {
2273 				dev->flags |= ATA_DFLAG_LBA48;
2274 				lba_desc = "LBA48";
2275 
2276 				if (dev->n_sectors >= (1UL << 28) &&
2277 				    ata_id_has_flush_ext(id))
2278 					dev->flags |= ATA_DFLAG_FLUSH_EXT;
2279 			}
2280 
2281 			/* config NCQ */
2282 			rc = ata_dev_config_ncq(dev, ncq_desc, sizeof(ncq_desc));
2283 			if (rc)
2284 				return rc;
2285 
2286 			/* print device info to dmesg */
2287 			if (ata_msg_drv(ap) && print_info) {
2288 				ata_dev_printk(dev, KERN_INFO,
2289 					"%s: %s, %s, max %s\n",
2290 					revbuf, modelbuf, fwrevbuf,
2291 					ata_mode_string(xfer_mask));
2292 				ata_dev_printk(dev, KERN_INFO,
2293 					"%Lu sectors, multi %u: %s %s\n",
2294 					(unsigned long long)dev->n_sectors,
2295 					dev->multi_count, lba_desc, ncq_desc);
2296 			}
2297 		} else {
2298 			/* CHS */
2299 
2300 			/* Default translation */
2301 			dev->cylinders	= id[1];
2302 			dev->heads	= id[3];
2303 			dev->sectors	= id[6];
2304 
2305 			if (ata_id_current_chs_valid(id)) {
2306 				/* Current CHS translation is valid. */
2307 				dev->cylinders = id[54];
2308 				dev->heads     = id[55];
2309 				dev->sectors   = id[56];
2310 			}
2311 
2312 			/* print device info to dmesg */
2313 			if (ata_msg_drv(ap) && print_info) {
2314 				ata_dev_printk(dev, KERN_INFO,
2315 					"%s: %s, %s, max %s\n",
2316 					revbuf,	modelbuf, fwrevbuf,
2317 					ata_mode_string(xfer_mask));
2318 				ata_dev_printk(dev, KERN_INFO,
2319 					"%Lu sectors, multi %u, CHS %u/%u/%u\n",
2320 					(unsigned long long)dev->n_sectors,
2321 					dev->multi_count, dev->cylinders,
2322 					dev->heads, dev->sectors);
2323 			}
2324 		}
2325 
2326 		dev->cdb_len = 16;
2327 	}
2328 
2329 	/* ATAPI-specific feature tests */
2330 	else if (dev->class == ATA_DEV_ATAPI) {
2331 		const char *cdb_intr_string = "";
2332 		const char *atapi_an_string = "";
2333 		const char *dma_dir_string = "";
2334 		u32 sntf;
2335 
2336 		rc = atapi_cdb_len(id);
2337 		if ((rc < 12) || (rc > ATAPI_CDB_LEN)) {
2338 			if (ata_msg_warn(ap))
2339 				ata_dev_printk(dev, KERN_WARNING,
2340 					       "unsupported CDB len\n");
2341 			rc = -EINVAL;
2342 			goto err_out_nosup;
2343 		}
2344 		dev->cdb_len = (unsigned int) rc;
2345 
2346 		/* Enable ATAPI AN if both the host and device have
2347 		 * the support.  If PMP is attached, SNTF is required
2348 		 * to enable ATAPI AN to discern between PHY status
2349 		 * changed notifications and ATAPI ANs.
2350 		 */
2351 		if (atapi_an &&
2352 		    (ap->flags & ATA_FLAG_AN) && ata_id_has_atapi_AN(id) &&
2353 		    (!sata_pmp_attached(ap) ||
2354 		     sata_scr_read(&ap->link, SCR_NOTIFICATION, &sntf) == 0)) {
2355 			unsigned int err_mask;
2356 
2357 			/* issue SET feature command to turn this on */
2358 			err_mask = ata_dev_set_feature(dev,
2359 					SETFEATURES_SATA_ENABLE, SATA_AN);
2360 			if (err_mask)
2361 				ata_dev_printk(dev, KERN_ERR,
2362 					"failed to enable ATAPI AN "
2363 					"(err_mask=0x%x)\n", err_mask);
2364 			else {
2365 				dev->flags |= ATA_DFLAG_AN;
2366 				atapi_an_string = ", ATAPI AN";
2367 			}
2368 		}
2369 
2370 		if (ata_id_cdb_intr(dev->id)) {
2371 			dev->flags |= ATA_DFLAG_CDB_INTR;
2372 			cdb_intr_string = ", CDB intr";
2373 		}
2374 
2375 		if (atapi_dmadir || atapi_id_dmadir(dev->id)) {
2376 			dev->flags |= ATA_DFLAG_DMADIR;
2377 			dma_dir_string = ", DMADIR";
2378 		}
2379 
2380 		/* print device info to dmesg */
2381 		if (ata_msg_drv(ap) && print_info)
2382 			ata_dev_printk(dev, KERN_INFO,
2383 				       "ATAPI: %s, %s, max %s%s%s%s\n",
2384 				       modelbuf, fwrevbuf,
2385 				       ata_mode_string(xfer_mask),
2386 				       cdb_intr_string, atapi_an_string,
2387 				       dma_dir_string);
2388 	}
2389 
2390 	/* determine max_sectors */
2391 	dev->max_sectors = ATA_MAX_SECTORS;
2392 	if (dev->flags & ATA_DFLAG_LBA48)
2393 		dev->max_sectors = ATA_MAX_SECTORS_LBA48;
2394 
2395 	/* Limit PATA drive on SATA cable bridge transfers to udma5,
2396 	   200 sectors */
2397 	if (ata_dev_knobble(dev)) {
2398 		if (ata_msg_drv(ap) && print_info)
2399 			ata_dev_printk(dev, KERN_INFO,
2400 				       "applying bridge limits\n");
2401 		dev->udma_mask &= ATA_UDMA5;
2402 		dev->max_sectors = ATA_MAX_SECTORS;
2403 	}
2404 
2405 	if ((dev->class == ATA_DEV_ATAPI) &&
2406 	    (atapi_command_packet_set(id) == TYPE_TAPE)) {
2407 		dev->max_sectors = ATA_MAX_SECTORS_TAPE;
2408 		dev->horkage |= ATA_HORKAGE_STUCK_ERR;
2409 	}
2410 
2411 	if (dev->horkage & ATA_HORKAGE_MAX_SEC_128)
2412 		dev->max_sectors = min_t(unsigned int, ATA_MAX_SECTORS_128,
2413 					 dev->max_sectors);
2414 
2415 	if (ap->ops->dev_config)
2416 		ap->ops->dev_config(dev);
2417 
2418 	if (dev->horkage & ATA_HORKAGE_DIAGNOSTIC) {
2419 		/* Let the user know. We don't want to disallow opens for
2420 		   rescue purposes, or in case the vendor is just a blithering
2421 		   idiot. Do this after the dev_config call as some controllers
2422 		   with buggy firmware may want to avoid reporting false device
2423 		   bugs */
2424 
2425 		if (print_info) {
2426 			ata_dev_printk(dev, KERN_WARNING,
2427 "Drive reports diagnostics failure. This may indicate a drive\n");
2428 			ata_dev_printk(dev, KERN_WARNING,
2429 "fault or invalid emulation. Contact drive vendor for information.\n");
2430 		}
2431 	}
2432 
2433 	if ((dev->horkage & ATA_HORKAGE_FIRMWARE_WARN) && print_info) {
2434 		ata_dev_printk(dev, KERN_WARNING, "WARNING: device requires "
2435 			       "firmware update to be fully functional.\n");
2436 		ata_dev_printk(dev, KERN_WARNING, "         contact the vendor "
2437 			       "or visit http://ata.wiki.kernel.org.\n");
2438 	}
2439 
2440 	return 0;
2441 
2442 err_out_nosup:
2443 	if (ata_msg_probe(ap))
2444 		ata_dev_printk(dev, KERN_DEBUG,
2445 			       "%s: EXIT, err\n", __func__);
2446 	return rc;
2447 }
2448 
2449 /**
2450  *	ata_cable_40wire	-	return 40 wire cable type
2451  *	@ap: port
2452  *
2453  *	Helper method for drivers which want to hardwire 40 wire cable
2454  *	detection.
2455  */
2456 
2457 int ata_cable_40wire(struct ata_port *ap)
2458 {
2459 	return ATA_CBL_PATA40;
2460 }
2461 
2462 /**
2463  *	ata_cable_80wire	-	return 80 wire cable type
2464  *	@ap: port
2465  *
2466  *	Helper method for drivers which want to hardwire 80 wire cable
2467  *	detection.
2468  */
2469 
2470 int ata_cable_80wire(struct ata_port *ap)
2471 {
2472 	return ATA_CBL_PATA80;
2473 }
2474 
2475 /**
2476  *	ata_cable_unknown	-	return unknown PATA cable.
2477  *	@ap: port
2478  *
2479  *	Helper method for drivers which have no PATA cable detection.
2480  */
2481 
2482 int ata_cable_unknown(struct ata_port *ap)
2483 {
2484 	return ATA_CBL_PATA_UNK;
2485 }
2486 
2487 /**
2488  *	ata_cable_ignore	-	return ignored PATA cable.
2489  *	@ap: port
2490  *
2491  *	Helper method for drivers which don't use cable type to limit
2492  *	transfer mode.
2493  */
2494 int ata_cable_ignore(struct ata_port *ap)
2495 {
2496 	return ATA_CBL_PATA_IGN;
2497 }
2498 
2499 /**
2500  *	ata_cable_sata	-	return SATA cable type
2501  *	@ap: port
2502  *
2503  *	Helper method for drivers which have SATA cables
2504  */
2505 
2506 int ata_cable_sata(struct ata_port *ap)
2507 {
2508 	return ATA_CBL_SATA;
2509 }
2510 
2511 /**
2512  *	ata_bus_probe - Reset and probe ATA bus
2513  *	@ap: Bus to probe
2514  *
2515  *	Master ATA bus probing function.  Initiates a hardware-dependent
2516  *	bus reset, then attempts to identify any devices found on
2517  *	the bus.
2518  *
2519  *	LOCKING:
2520  *	PCI/etc. bus probe sem.
2521  *
2522  *	RETURNS:
2523  *	Zero on success, negative errno otherwise.
2524  */
2525 
2526 int ata_bus_probe(struct ata_port *ap)
2527 {
2528 	unsigned int classes[ATA_MAX_DEVICES];
2529 	int tries[ATA_MAX_DEVICES];
2530 	int rc;
2531 	struct ata_device *dev;
2532 
2533 	ata_for_each_dev(dev, &ap->link, ALL)
2534 		tries[dev->devno] = ATA_PROBE_MAX_TRIES;
2535 
2536  retry:
2537 	ata_for_each_dev(dev, &ap->link, ALL) {
2538 		/* If we issue an SRST then an ATA drive (not ATAPI)
2539 		 * may change configuration and be in PIO0 timing. If
2540 		 * we do a hard reset (or are coming from power on)
2541 		 * this is true for ATA or ATAPI. Until we've set a
2542 		 * suitable controller mode we should not touch the
2543 		 * bus as we may be talking too fast.
2544 		 */
2545 		dev->pio_mode = XFER_PIO_0;
2546 
2547 		/* If the controller has a pio mode setup function
2548 		 * then use it to set the chipset to rights. Don't
2549 		 * touch the DMA setup as that will be dealt with when
2550 		 * configuring devices.
2551 		 */
2552 		if (ap->ops->set_piomode)
2553 			ap->ops->set_piomode(ap, dev);
2554 	}
2555 
2556 	/* reset and determine device classes */
2557 	ap->ops->phy_reset(ap);
2558 
2559 	ata_for_each_dev(dev, &ap->link, ALL) {
2560 		if (dev->class != ATA_DEV_UNKNOWN)
2561 			classes[dev->devno] = dev->class;
2562 		else
2563 			classes[dev->devno] = ATA_DEV_NONE;
2564 
2565 		dev->class = ATA_DEV_UNKNOWN;
2566 	}
2567 
2568 	/* read IDENTIFY page and configure devices. We have to do the identify
2569 	   specific sequence bass-ackwards so that PDIAG- is released by
2570 	   the slave device */
2571 
2572 	ata_for_each_dev(dev, &ap->link, ALL_REVERSE) {
2573 		if (tries[dev->devno])
2574 			dev->class = classes[dev->devno];
2575 
2576 		if (!ata_dev_enabled(dev))
2577 			continue;
2578 
2579 		rc = ata_dev_read_id(dev, &dev->class, ATA_READID_POSTRESET,
2580 				     dev->id);
2581 		if (rc)
2582 			goto fail;
2583 	}
2584 
2585 	/* Now ask for the cable type as PDIAG- should have been released */
2586 	if (ap->ops->cable_detect)
2587 		ap->cbl = ap->ops->cable_detect(ap);
2588 
2589 	/* We may have SATA bridge glue hiding here irrespective of
2590 	 * the reported cable types and sensed types.  When SATA
2591 	 * drives indicate we have a bridge, we don't know which end
2592 	 * of the link the bridge is which is a problem.
2593 	 */
2594 	ata_for_each_dev(dev, &ap->link, ENABLED)
2595 		if (ata_id_is_sata(dev->id))
2596 			ap->cbl = ATA_CBL_SATA;
2597 
2598 	/* After the identify sequence we can now set up the devices. We do
2599 	   this in the normal order so that the user doesn't get confused */
2600 
2601 	ata_for_each_dev(dev, &ap->link, ENABLED) {
2602 		ap->link.eh_context.i.flags |= ATA_EHI_PRINTINFO;
2603 		rc = ata_dev_configure(dev);
2604 		ap->link.eh_context.i.flags &= ~ATA_EHI_PRINTINFO;
2605 		if (rc)
2606 			goto fail;
2607 	}
2608 
2609 	/* configure transfer mode */
2610 	rc = ata_set_mode(&ap->link, &dev);
2611 	if (rc)
2612 		goto fail;
2613 
2614 	ata_for_each_dev(dev, &ap->link, ENABLED)
2615 		return 0;
2616 
2617 	return -ENODEV;
2618 
2619  fail:
2620 	tries[dev->devno]--;
2621 
2622 	switch (rc) {
2623 	case -EINVAL:
2624 		/* eeek, something went very wrong, give up */
2625 		tries[dev->devno] = 0;
2626 		break;
2627 
2628 	case -ENODEV:
2629 		/* give it just one more chance */
2630 		tries[dev->devno] = min(tries[dev->devno], 1);
2631 	case -EIO:
2632 		if (tries[dev->devno] == 1) {
2633 			/* This is the last chance, better to slow
2634 			 * down than lose it.
2635 			 */
2636 			sata_down_spd_limit(&ap->link, 0);
2637 			ata_down_xfermask_limit(dev, ATA_DNXFER_PIO);
2638 		}
2639 	}
2640 
2641 	if (!tries[dev->devno])
2642 		ata_dev_disable(dev);
2643 
2644 	goto retry;
2645 }
2646 
2647 /**
2648  *	sata_print_link_status - Print SATA link status
2649  *	@link: SATA link to printk link status about
2650  *
2651  *	This function prints link speed and status of a SATA link.
2652  *
2653  *	LOCKING:
2654  *	None.
2655  */
2656 static void sata_print_link_status(struct ata_link *link)
2657 {
2658 	u32 sstatus, scontrol, tmp;
2659 
2660 	if (sata_scr_read(link, SCR_STATUS, &sstatus))
2661 		return;
2662 	sata_scr_read(link, SCR_CONTROL, &scontrol);
2663 
2664 	if (ata_phys_link_online(link)) {
2665 		tmp = (sstatus >> 4) & 0xf;
2666 		ata_link_printk(link, KERN_INFO,
2667 				"SATA link up %s (SStatus %X SControl %X)\n",
2668 				sata_spd_string(tmp), sstatus, scontrol);
2669 	} else {
2670 		ata_link_printk(link, KERN_INFO,
2671 				"SATA link down (SStatus %X SControl %X)\n",
2672 				sstatus, scontrol);
2673 	}
2674 }
2675 
2676 /**
2677  *	ata_dev_pair		-	return other device on cable
2678  *	@adev: device
2679  *
2680  *	Obtain the other device on the same cable, or if none is
2681  *	present NULL is returned
2682  */
2683 
2684 struct ata_device *ata_dev_pair(struct ata_device *adev)
2685 {
2686 	struct ata_link *link = adev->link;
2687 	struct ata_device *pair = &link->device[1 - adev->devno];
2688 	if (!ata_dev_enabled(pair))
2689 		return NULL;
2690 	return pair;
2691 }
2692 
2693 /**
2694  *	sata_down_spd_limit - adjust SATA spd limit downward
2695  *	@link: Link to adjust SATA spd limit for
2696  *	@spd_limit: Additional limit
2697  *
2698  *	Adjust SATA spd limit of @link downward.  Note that this
2699  *	function only adjusts the limit.  The change must be applied
2700  *	using sata_set_spd().
2701  *
2702  *	If @spd_limit is non-zero, the speed is limited to equal to or
2703  *	lower than @spd_limit if such speed is supported.  If
2704  *	@spd_limit is slower than any supported speed, only the lowest
2705  *	supported speed is allowed.
2706  *
2707  *	LOCKING:
2708  *	Inherited from caller.
2709  *
2710  *	RETURNS:
2711  *	0 on success, negative errno on failure
2712  */
2713 int sata_down_spd_limit(struct ata_link *link, u32 spd_limit)
2714 {
2715 	u32 sstatus, spd, mask;
2716 	int rc, bit;
2717 
2718 	if (!sata_scr_valid(link))
2719 		return -EOPNOTSUPP;
2720 
2721 	/* If SCR can be read, use it to determine the current SPD.
2722 	 * If not, use cached value in link->sata_spd.
2723 	 */
2724 	rc = sata_scr_read(link, SCR_STATUS, &sstatus);
2725 	if (rc == 0 && ata_sstatus_online(sstatus))
2726 		spd = (sstatus >> 4) & 0xf;
2727 	else
2728 		spd = link->sata_spd;
2729 
2730 	mask = link->sata_spd_limit;
2731 	if (mask <= 1)
2732 		return -EINVAL;
2733 
2734 	/* unconditionally mask off the highest bit */
2735 	bit = fls(mask) - 1;
2736 	mask &= ~(1 << bit);
2737 
2738 	/* Mask off all speeds higher than or equal to the current
2739 	 * one.  Force 1.5Gbps if current SPD is not available.
2740 	 */
2741 	if (spd > 1)
2742 		mask &= (1 << (spd - 1)) - 1;
2743 	else
2744 		mask &= 1;
2745 
2746 	/* were we already at the bottom? */
2747 	if (!mask)
2748 		return -EINVAL;
2749 
2750 	if (spd_limit) {
2751 		if (mask & ((1 << spd_limit) - 1))
2752 			mask &= (1 << spd_limit) - 1;
2753 		else {
2754 			bit = ffs(mask) - 1;
2755 			mask = 1 << bit;
2756 		}
2757 	}
2758 
2759 	link->sata_spd_limit = mask;
2760 
2761 	ata_link_printk(link, KERN_WARNING, "limiting SATA link speed to %s\n",
2762 			sata_spd_string(fls(mask)));
2763 
2764 	return 0;
2765 }
2766 
2767 static int __sata_set_spd_needed(struct ata_link *link, u32 *scontrol)
2768 {
2769 	struct ata_link *host_link = &link->ap->link;
2770 	u32 limit, target, spd;
2771 
2772 	limit = link->sata_spd_limit;
2773 
2774 	/* Don't configure downstream link faster than upstream link.
2775 	 * It doesn't speed up anything and some PMPs choke on such
2776 	 * configuration.
2777 	 */
2778 	if (!ata_is_host_link(link) && host_link->sata_spd)
2779 		limit &= (1 << host_link->sata_spd) - 1;
2780 
2781 	if (limit == UINT_MAX)
2782 		target = 0;
2783 	else
2784 		target = fls(limit);
2785 
2786 	spd = (*scontrol >> 4) & 0xf;
2787 	*scontrol = (*scontrol & ~0xf0) | ((target & 0xf) << 4);
2788 
2789 	return spd != target;
2790 }
2791 
2792 /**
2793  *	sata_set_spd_needed - is SATA spd configuration needed
2794  *	@link: Link in question
2795  *
2796  *	Test whether the spd limit in SControl matches
2797  *	@link->sata_spd_limit.  This function is used to determine
2798  *	whether hardreset is necessary to apply SATA spd
2799  *	configuration.
2800  *
2801  *	LOCKING:
2802  *	Inherited from caller.
2803  *
2804  *	RETURNS:
2805  *	1 if SATA spd configuration is needed, 0 otherwise.
2806  */
2807 static int sata_set_spd_needed(struct ata_link *link)
2808 {
2809 	u32 scontrol;
2810 
2811 	if (sata_scr_read(link, SCR_CONTROL, &scontrol))
2812 		return 1;
2813 
2814 	return __sata_set_spd_needed(link, &scontrol);
2815 }
2816 
2817 /**
2818  *	sata_set_spd - set SATA spd according to spd limit
2819  *	@link: Link to set SATA spd for
2820  *
2821  *	Set SATA spd of @link according to sata_spd_limit.
2822  *
2823  *	LOCKING:
2824  *	Inherited from caller.
2825  *
2826  *	RETURNS:
2827  *	0 if spd doesn't need to be changed, 1 if spd has been
2828  *	changed.  Negative errno if SCR registers are inaccessible.
2829  */
2830 int sata_set_spd(struct ata_link *link)
2831 {
2832 	u32 scontrol;
2833 	int rc;
2834 
2835 	if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
2836 		return rc;
2837 
2838 	if (!__sata_set_spd_needed(link, &scontrol))
2839 		return 0;
2840 
2841 	if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
2842 		return rc;
2843 
2844 	return 1;
2845 }
2846 
2847 /*
2848  * This mode timing computation functionality is ported over from
2849  * drivers/ide/ide-timing.h and was originally written by Vojtech Pavlik
2850  */
2851 /*
2852  * PIO 0-4, MWDMA 0-2 and UDMA 0-6 timings (in nanoseconds).
2853  * These were taken from ATA/ATAPI-6 standard, rev 0a, except
2854  * for UDMA6, which is currently supported only by Maxtor drives.
2855  *
2856  * For PIO 5/6 MWDMA 3/4 see the CFA specification 3.0.
2857  */
2858 
2859 static const struct ata_timing ata_timing[] = {
2860 /*	{ XFER_PIO_SLOW, 120, 290, 240, 960, 290, 240, 0,  960,   0 }, */
2861 	{ XFER_PIO_0,     70, 290, 240, 600, 165, 150, 0,  600,   0 },
2862 	{ XFER_PIO_1,     50, 290,  93, 383, 125, 100, 0,  383,   0 },
2863 	{ XFER_PIO_2,     30, 290,  40, 330, 100,  90, 0,  240,   0 },
2864 	{ XFER_PIO_3,     30,  80,  70, 180,  80,  70, 0,  180,   0 },
2865 	{ XFER_PIO_4,     25,  70,  25, 120,  70,  25, 0,  120,   0 },
2866 	{ XFER_PIO_5,     15,  65,  25, 100,  65,  25, 0,  100,   0 },
2867 	{ XFER_PIO_6,     10,  55,  20,  80,  55,  20, 0,   80,   0 },
2868 
2869 	{ XFER_SW_DMA_0, 120,   0,   0,   0, 480, 480, 50, 960,   0 },
2870 	{ XFER_SW_DMA_1,  90,   0,   0,   0, 240, 240, 30, 480,   0 },
2871 	{ XFER_SW_DMA_2,  60,   0,   0,   0, 120, 120, 20, 240,   0 },
2872 
2873 	{ XFER_MW_DMA_0,  60,   0,   0,   0, 215, 215, 20, 480,   0 },
2874 	{ XFER_MW_DMA_1,  45,   0,   0,   0,  80,  50, 5,  150,   0 },
2875 	{ XFER_MW_DMA_2,  25,   0,   0,   0,  70,  25, 5,  120,   0 },
2876 	{ XFER_MW_DMA_3,  25,   0,   0,   0,  65,  25, 5,  100,   0 },
2877 	{ XFER_MW_DMA_4,  25,   0,   0,   0,  55,  20, 5,   80,   0 },
2878 
2879 /*	{ XFER_UDMA_SLOW,  0,   0,   0,   0,   0,   0, 0,    0, 150 }, */
2880 	{ XFER_UDMA_0,     0,   0,   0,   0,   0,   0, 0,    0, 120 },
2881 	{ XFER_UDMA_1,     0,   0,   0,   0,   0,   0, 0,    0,  80 },
2882 	{ XFER_UDMA_2,     0,   0,   0,   0,   0,   0, 0,    0,  60 },
2883 	{ XFER_UDMA_3,     0,   0,   0,   0,   0,   0, 0,    0,  45 },
2884 	{ XFER_UDMA_4,     0,   0,   0,   0,   0,   0, 0,    0,  30 },
2885 	{ XFER_UDMA_5,     0,   0,   0,   0,   0,   0, 0,    0,  20 },
2886 	{ XFER_UDMA_6,     0,   0,   0,   0,   0,   0, 0,    0,  15 },
2887 
2888 	{ 0xFF }
2889 };
2890 
2891 #define ENOUGH(v, unit)		(((v)-1)/(unit)+1)
2892 #define EZ(v, unit)		((v)?ENOUGH(v, unit):0)
2893 
2894 static void ata_timing_quantize(const struct ata_timing *t, struct ata_timing *q, int T, int UT)
2895 {
2896 	q->setup	= EZ(t->setup      * 1000,  T);
2897 	q->act8b	= EZ(t->act8b      * 1000,  T);
2898 	q->rec8b	= EZ(t->rec8b      * 1000,  T);
2899 	q->cyc8b	= EZ(t->cyc8b      * 1000,  T);
2900 	q->active	= EZ(t->active     * 1000,  T);
2901 	q->recover	= EZ(t->recover    * 1000,  T);
2902 	q->dmack_hold	= EZ(t->dmack_hold * 1000,  T);
2903 	q->cycle	= EZ(t->cycle      * 1000,  T);
2904 	q->udma		= EZ(t->udma       * 1000, UT);
2905 }
2906 
2907 void ata_timing_merge(const struct ata_timing *a, const struct ata_timing *b,
2908 		      struct ata_timing *m, unsigned int what)
2909 {
2910 	if (what & ATA_TIMING_SETUP  ) m->setup   = max(a->setup,   b->setup);
2911 	if (what & ATA_TIMING_ACT8B  ) m->act8b   = max(a->act8b,   b->act8b);
2912 	if (what & ATA_TIMING_REC8B  ) m->rec8b   = max(a->rec8b,   b->rec8b);
2913 	if (what & ATA_TIMING_CYC8B  ) m->cyc8b   = max(a->cyc8b,   b->cyc8b);
2914 	if (what & ATA_TIMING_ACTIVE ) m->active  = max(a->active,  b->active);
2915 	if (what & ATA_TIMING_RECOVER) m->recover = max(a->recover, b->recover);
2916 	if (what & ATA_TIMING_DMACK_HOLD) m->dmack_hold = max(a->dmack_hold, b->dmack_hold);
2917 	if (what & ATA_TIMING_CYCLE  ) m->cycle   = max(a->cycle,   b->cycle);
2918 	if (what & ATA_TIMING_UDMA   ) m->udma    = max(a->udma,    b->udma);
2919 }
2920 
2921 const struct ata_timing *ata_timing_find_mode(u8 xfer_mode)
2922 {
2923 	const struct ata_timing *t = ata_timing;
2924 
2925 	while (xfer_mode > t->mode)
2926 		t++;
2927 
2928 	if (xfer_mode == t->mode)
2929 		return t;
2930 	return NULL;
2931 }
2932 
2933 int ata_timing_compute(struct ata_device *adev, unsigned short speed,
2934 		       struct ata_timing *t, int T, int UT)
2935 {
2936 	const u16 *id = adev->id;
2937 	const struct ata_timing *s;
2938 	struct ata_timing p;
2939 
2940 	/*
2941 	 * Find the mode.
2942 	 */
2943 
2944 	if (!(s = ata_timing_find_mode(speed)))
2945 		return -EINVAL;
2946 
2947 	memcpy(t, s, sizeof(*s));
2948 
2949 	/*
2950 	 * If the drive is an EIDE drive, it can tell us it needs extended
2951 	 * PIO/MW_DMA cycle timing.
2952 	 */
2953 
2954 	if (id[ATA_ID_FIELD_VALID] & 2) {	/* EIDE drive */
2955 		memset(&p, 0, sizeof(p));
2956 
2957 		if (speed >= XFER_PIO_0 && speed <= XFER_SW_DMA_0) {
2958 			if (speed <= XFER_PIO_2)
2959 				p.cycle = p.cyc8b = id[ATA_ID_EIDE_PIO];
2960 			else if ((speed <= XFER_PIO_4) ||
2961 				 (speed == XFER_PIO_5 && !ata_id_is_cfa(id)))
2962 				p.cycle = p.cyc8b = id[ATA_ID_EIDE_PIO_IORDY];
2963 		} else if (speed >= XFER_MW_DMA_0 && speed <= XFER_MW_DMA_2)
2964 			p.cycle = id[ATA_ID_EIDE_DMA_MIN];
2965 
2966 		ata_timing_merge(&p, t, t, ATA_TIMING_CYCLE | ATA_TIMING_CYC8B);
2967 	}
2968 
2969 	/*
2970 	 * Convert the timing to bus clock counts.
2971 	 */
2972 
2973 	ata_timing_quantize(t, t, T, UT);
2974 
2975 	/*
2976 	 * Even in DMA/UDMA modes we still use PIO access for IDENTIFY,
2977 	 * S.M.A.R.T * and some other commands. We have to ensure that the
2978 	 * DMA cycle timing is slower/equal than the fastest PIO timing.
2979 	 */
2980 
2981 	if (speed > XFER_PIO_6) {
2982 		ata_timing_compute(adev, adev->pio_mode, &p, T, UT);
2983 		ata_timing_merge(&p, t, t, ATA_TIMING_ALL);
2984 	}
2985 
2986 	/*
2987 	 * Lengthen active & recovery time so that cycle time is correct.
2988 	 */
2989 
2990 	if (t->act8b + t->rec8b < t->cyc8b) {
2991 		t->act8b += (t->cyc8b - (t->act8b + t->rec8b)) / 2;
2992 		t->rec8b = t->cyc8b - t->act8b;
2993 	}
2994 
2995 	if (t->active + t->recover < t->cycle) {
2996 		t->active += (t->cycle - (t->active + t->recover)) / 2;
2997 		t->recover = t->cycle - t->active;
2998 	}
2999 
3000 	/* In a few cases quantisation may produce enough errors to
3001 	   leave t->cycle too low for the sum of active and recovery
3002 	   if so we must correct this */
3003 	if (t->active + t->recover > t->cycle)
3004 		t->cycle = t->active + t->recover;
3005 
3006 	return 0;
3007 }
3008 
3009 /**
3010  *	ata_timing_cycle2mode - find xfer mode for the specified cycle duration
3011  *	@xfer_shift: ATA_SHIFT_* value for transfer type to examine.
3012  *	@cycle: cycle duration in ns
3013  *
3014  *	Return matching xfer mode for @cycle.  The returned mode is of
3015  *	the transfer type specified by @xfer_shift.  If @cycle is too
3016  *	slow for @xfer_shift, 0xff is returned.  If @cycle is faster
3017  *	than the fastest known mode, the fasted mode is returned.
3018  *
3019  *	LOCKING:
3020  *	None.
3021  *
3022  *	RETURNS:
3023  *	Matching xfer_mode, 0xff if no match found.
3024  */
3025 u8 ata_timing_cycle2mode(unsigned int xfer_shift, int cycle)
3026 {
3027 	u8 base_mode = 0xff, last_mode = 0xff;
3028 	const struct ata_xfer_ent *ent;
3029 	const struct ata_timing *t;
3030 
3031 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
3032 		if (ent->shift == xfer_shift)
3033 			base_mode = ent->base;
3034 
3035 	for (t = ata_timing_find_mode(base_mode);
3036 	     t && ata_xfer_mode2shift(t->mode) == xfer_shift; t++) {
3037 		unsigned short this_cycle;
3038 
3039 		switch (xfer_shift) {
3040 		case ATA_SHIFT_PIO:
3041 		case ATA_SHIFT_MWDMA:
3042 			this_cycle = t->cycle;
3043 			break;
3044 		case ATA_SHIFT_UDMA:
3045 			this_cycle = t->udma;
3046 			break;
3047 		default:
3048 			return 0xff;
3049 		}
3050 
3051 		if (cycle > this_cycle)
3052 			break;
3053 
3054 		last_mode = t->mode;
3055 	}
3056 
3057 	return last_mode;
3058 }
3059 
3060 /**
3061  *	ata_down_xfermask_limit - adjust dev xfer masks downward
3062  *	@dev: Device to adjust xfer masks
3063  *	@sel: ATA_DNXFER_* selector
3064  *
3065  *	Adjust xfer masks of @dev downward.  Note that this function
3066  *	does not apply the change.  Invoking ata_set_mode() afterwards
3067  *	will apply the limit.
3068  *
3069  *	LOCKING:
3070  *	Inherited from caller.
3071  *
3072  *	RETURNS:
3073  *	0 on success, negative errno on failure
3074  */
3075 int ata_down_xfermask_limit(struct ata_device *dev, unsigned int sel)
3076 {
3077 	char buf[32];
3078 	unsigned long orig_mask, xfer_mask;
3079 	unsigned long pio_mask, mwdma_mask, udma_mask;
3080 	int quiet, highbit;
3081 
3082 	quiet = !!(sel & ATA_DNXFER_QUIET);
3083 	sel &= ~ATA_DNXFER_QUIET;
3084 
3085 	xfer_mask = orig_mask = ata_pack_xfermask(dev->pio_mask,
3086 						  dev->mwdma_mask,
3087 						  dev->udma_mask);
3088 	ata_unpack_xfermask(xfer_mask, &pio_mask, &mwdma_mask, &udma_mask);
3089 
3090 	switch (sel) {
3091 	case ATA_DNXFER_PIO:
3092 		highbit = fls(pio_mask) - 1;
3093 		pio_mask &= ~(1 << highbit);
3094 		break;
3095 
3096 	case ATA_DNXFER_DMA:
3097 		if (udma_mask) {
3098 			highbit = fls(udma_mask) - 1;
3099 			udma_mask &= ~(1 << highbit);
3100 			if (!udma_mask)
3101 				return -ENOENT;
3102 		} else if (mwdma_mask) {
3103 			highbit = fls(mwdma_mask) - 1;
3104 			mwdma_mask &= ~(1 << highbit);
3105 			if (!mwdma_mask)
3106 				return -ENOENT;
3107 		}
3108 		break;
3109 
3110 	case ATA_DNXFER_40C:
3111 		udma_mask &= ATA_UDMA_MASK_40C;
3112 		break;
3113 
3114 	case ATA_DNXFER_FORCE_PIO0:
3115 		pio_mask &= 1;
3116 	case ATA_DNXFER_FORCE_PIO:
3117 		mwdma_mask = 0;
3118 		udma_mask = 0;
3119 		break;
3120 
3121 	default:
3122 		BUG();
3123 	}
3124 
3125 	xfer_mask &= ata_pack_xfermask(pio_mask, mwdma_mask, udma_mask);
3126 
3127 	if (!(xfer_mask & ATA_MASK_PIO) || xfer_mask == orig_mask)
3128 		return -ENOENT;
3129 
3130 	if (!quiet) {
3131 		if (xfer_mask & (ATA_MASK_MWDMA | ATA_MASK_UDMA))
3132 			snprintf(buf, sizeof(buf), "%s:%s",
3133 				 ata_mode_string(xfer_mask),
3134 				 ata_mode_string(xfer_mask & ATA_MASK_PIO));
3135 		else
3136 			snprintf(buf, sizeof(buf), "%s",
3137 				 ata_mode_string(xfer_mask));
3138 
3139 		ata_dev_printk(dev, KERN_WARNING,
3140 			       "limiting speed to %s\n", buf);
3141 	}
3142 
3143 	ata_unpack_xfermask(xfer_mask, &dev->pio_mask, &dev->mwdma_mask,
3144 			    &dev->udma_mask);
3145 
3146 	return 0;
3147 }
3148 
3149 static int ata_dev_set_mode(struct ata_device *dev)
3150 {
3151 	struct ata_port *ap = dev->link->ap;
3152 	struct ata_eh_context *ehc = &dev->link->eh_context;
3153 	const bool nosetxfer = dev->horkage & ATA_HORKAGE_NOSETXFER;
3154 	const char *dev_err_whine = "";
3155 	int ign_dev_err = 0;
3156 	unsigned int err_mask = 0;
3157 	int rc;
3158 
3159 	dev->flags &= ~ATA_DFLAG_PIO;
3160 	if (dev->xfer_shift == ATA_SHIFT_PIO)
3161 		dev->flags |= ATA_DFLAG_PIO;
3162 
3163 	if (nosetxfer && ap->flags & ATA_FLAG_SATA && ata_id_is_sata(dev->id))
3164 		dev_err_whine = " (SET_XFERMODE skipped)";
3165 	else {
3166 		if (nosetxfer)
3167 			ata_dev_printk(dev, KERN_WARNING,
3168 				       "NOSETXFER but PATA detected - can't "
3169 				       "skip SETXFER, might malfunction\n");
3170 		err_mask = ata_dev_set_xfermode(dev);
3171 	}
3172 
3173 	if (err_mask & ~AC_ERR_DEV)
3174 		goto fail;
3175 
3176 	/* revalidate */
3177 	ehc->i.flags |= ATA_EHI_POST_SETMODE;
3178 	rc = ata_dev_revalidate(dev, ATA_DEV_UNKNOWN, 0);
3179 	ehc->i.flags &= ~ATA_EHI_POST_SETMODE;
3180 	if (rc)
3181 		return rc;
3182 
3183 	if (dev->xfer_shift == ATA_SHIFT_PIO) {
3184 		/* Old CFA may refuse this command, which is just fine */
3185 		if (ata_id_is_cfa(dev->id))
3186 			ign_dev_err = 1;
3187 		/* Catch several broken garbage emulations plus some pre
3188 		   ATA devices */
3189 		if (ata_id_major_version(dev->id) == 0 &&
3190 					dev->pio_mode <= XFER_PIO_2)
3191 			ign_dev_err = 1;
3192 		/* Some very old devices and some bad newer ones fail
3193 		   any kind of SET_XFERMODE request but support PIO0-2
3194 		   timings and no IORDY */
3195 		if (!ata_id_has_iordy(dev->id) && dev->pio_mode <= XFER_PIO_2)
3196 			ign_dev_err = 1;
3197 	}
3198 	/* Early MWDMA devices do DMA but don't allow DMA mode setting.
3199 	   Don't fail an MWDMA0 set IFF the device indicates it is in MWDMA0 */
3200 	if (dev->xfer_shift == ATA_SHIFT_MWDMA &&
3201 	    dev->dma_mode == XFER_MW_DMA_0 &&
3202 	    (dev->id[63] >> 8) & 1)
3203 		ign_dev_err = 1;
3204 
3205 	/* if the device is actually configured correctly, ignore dev err */
3206 	if (dev->xfer_mode == ata_xfer_mask2mode(ata_id_xfermask(dev->id)))
3207 		ign_dev_err = 1;
3208 
3209 	if (err_mask & AC_ERR_DEV) {
3210 		if (!ign_dev_err)
3211 			goto fail;
3212 		else
3213 			dev_err_whine = " (device error ignored)";
3214 	}
3215 
3216 	DPRINTK("xfer_shift=%u, xfer_mode=0x%x\n",
3217 		dev->xfer_shift, (int)dev->xfer_mode);
3218 
3219 	ata_dev_printk(dev, KERN_INFO, "configured for %s%s\n",
3220 		       ata_mode_string(ata_xfer_mode2mask(dev->xfer_mode)),
3221 		       dev_err_whine);
3222 
3223 	return 0;
3224 
3225  fail:
3226 	ata_dev_printk(dev, KERN_ERR, "failed to set xfermode "
3227 		       "(err_mask=0x%x)\n", err_mask);
3228 	return -EIO;
3229 }
3230 
3231 /**
3232  *	ata_do_set_mode - Program timings and issue SET FEATURES - XFER
3233  *	@link: link on which timings will be programmed
3234  *	@r_failed_dev: out parameter for failed device
3235  *
3236  *	Standard implementation of the function used to tune and set
3237  *	ATA device disk transfer mode (PIO3, UDMA6, etc.).  If
3238  *	ata_dev_set_mode() fails, pointer to the failing device is
3239  *	returned in @r_failed_dev.
3240  *
3241  *	LOCKING:
3242  *	PCI/etc. bus probe sem.
3243  *
3244  *	RETURNS:
3245  *	0 on success, negative errno otherwise
3246  */
3247 
3248 int ata_do_set_mode(struct ata_link *link, struct ata_device **r_failed_dev)
3249 {
3250 	struct ata_port *ap = link->ap;
3251 	struct ata_device *dev;
3252 	int rc = 0, used_dma = 0, found = 0;
3253 
3254 	/* step 1: calculate xfer_mask */
3255 	ata_for_each_dev(dev, link, ENABLED) {
3256 		unsigned long pio_mask, dma_mask;
3257 		unsigned int mode_mask;
3258 
3259 		mode_mask = ATA_DMA_MASK_ATA;
3260 		if (dev->class == ATA_DEV_ATAPI)
3261 			mode_mask = ATA_DMA_MASK_ATAPI;
3262 		else if (ata_id_is_cfa(dev->id))
3263 			mode_mask = ATA_DMA_MASK_CFA;
3264 
3265 		ata_dev_xfermask(dev);
3266 		ata_force_xfermask(dev);
3267 
3268 		pio_mask = ata_pack_xfermask(dev->pio_mask, 0, 0);
3269 		dma_mask = ata_pack_xfermask(0, dev->mwdma_mask, dev->udma_mask);
3270 
3271 		if (libata_dma_mask & mode_mask)
3272 			dma_mask = ata_pack_xfermask(0, dev->mwdma_mask, dev->udma_mask);
3273 		else
3274 			dma_mask = 0;
3275 
3276 		dev->pio_mode = ata_xfer_mask2mode(pio_mask);
3277 		dev->dma_mode = ata_xfer_mask2mode(dma_mask);
3278 
3279 		found = 1;
3280 		if (ata_dma_enabled(dev))
3281 			used_dma = 1;
3282 	}
3283 	if (!found)
3284 		goto out;
3285 
3286 	/* step 2: always set host PIO timings */
3287 	ata_for_each_dev(dev, link, ENABLED) {
3288 		if (dev->pio_mode == 0xff) {
3289 			ata_dev_printk(dev, KERN_WARNING, "no PIO support\n");
3290 			rc = -EINVAL;
3291 			goto out;
3292 		}
3293 
3294 		dev->xfer_mode = dev->pio_mode;
3295 		dev->xfer_shift = ATA_SHIFT_PIO;
3296 		if (ap->ops->set_piomode)
3297 			ap->ops->set_piomode(ap, dev);
3298 	}
3299 
3300 	/* step 3: set host DMA timings */
3301 	ata_for_each_dev(dev, link, ENABLED) {
3302 		if (!ata_dma_enabled(dev))
3303 			continue;
3304 
3305 		dev->xfer_mode = dev->dma_mode;
3306 		dev->xfer_shift = ata_xfer_mode2shift(dev->dma_mode);
3307 		if (ap->ops->set_dmamode)
3308 			ap->ops->set_dmamode(ap, dev);
3309 	}
3310 
3311 	/* step 4: update devices' xfer mode */
3312 	ata_for_each_dev(dev, link, ENABLED) {
3313 		rc = ata_dev_set_mode(dev);
3314 		if (rc)
3315 			goto out;
3316 	}
3317 
3318 	/* Record simplex status. If we selected DMA then the other
3319 	 * host channels are not permitted to do so.
3320 	 */
3321 	if (used_dma && (ap->host->flags & ATA_HOST_SIMPLEX))
3322 		ap->host->simplex_claimed = ap;
3323 
3324  out:
3325 	if (rc)
3326 		*r_failed_dev = dev;
3327 	return rc;
3328 }
3329 
3330 /**
3331  *	ata_wait_ready - wait for link to become ready
3332  *	@link: link to be waited on
3333  *	@deadline: deadline jiffies for the operation
3334  *	@check_ready: callback to check link readiness
3335  *
3336  *	Wait for @link to become ready.  @check_ready should return
3337  *	positive number if @link is ready, 0 if it isn't, -ENODEV if
3338  *	link doesn't seem to be occupied, other errno for other error
3339  *	conditions.
3340  *
3341  *	Transient -ENODEV conditions are allowed for
3342  *	ATA_TMOUT_FF_WAIT.
3343  *
3344  *	LOCKING:
3345  *	EH context.
3346  *
3347  *	RETURNS:
3348  *	0 if @linke is ready before @deadline; otherwise, -errno.
3349  */
3350 int ata_wait_ready(struct ata_link *link, unsigned long deadline,
3351 		   int (*check_ready)(struct ata_link *link))
3352 {
3353 	unsigned long start = jiffies;
3354 	unsigned long nodev_deadline;
3355 	int warned = 0;
3356 
3357 	/* choose which 0xff timeout to use, read comment in libata.h */
3358 	if (link->ap->host->flags & ATA_HOST_PARALLEL_SCAN)
3359 		nodev_deadline = ata_deadline(start, ATA_TMOUT_FF_WAIT_LONG);
3360 	else
3361 		nodev_deadline = ata_deadline(start, ATA_TMOUT_FF_WAIT);
3362 
3363 	/* Slave readiness can't be tested separately from master.  On
3364 	 * M/S emulation configuration, this function should be called
3365 	 * only on the master and it will handle both master and slave.
3366 	 */
3367 	WARN_ON(link == link->ap->slave_link);
3368 
3369 	if (time_after(nodev_deadline, deadline))
3370 		nodev_deadline = deadline;
3371 
3372 	while (1) {
3373 		unsigned long now = jiffies;
3374 		int ready, tmp;
3375 
3376 		ready = tmp = check_ready(link);
3377 		if (ready > 0)
3378 			return 0;
3379 
3380 		/*
3381 		 * -ENODEV could be transient.  Ignore -ENODEV if link
3382 		 * is online.  Also, some SATA devices take a long
3383 		 * time to clear 0xff after reset.  Wait for
3384 		 * ATA_TMOUT_FF_WAIT[_LONG] on -ENODEV if link isn't
3385 		 * offline.
3386 		 *
3387 		 * Note that some PATA controllers (pata_ali) explode
3388 		 * if status register is read more than once when
3389 		 * there's no device attached.
3390 		 */
3391 		if (ready == -ENODEV) {
3392 			if (ata_link_online(link))
3393 				ready = 0;
3394 			else if ((link->ap->flags & ATA_FLAG_SATA) &&
3395 				 !ata_link_offline(link) &&
3396 				 time_before(now, nodev_deadline))
3397 				ready = 0;
3398 		}
3399 
3400 		if (ready)
3401 			return ready;
3402 		if (time_after(now, deadline))
3403 			return -EBUSY;
3404 
3405 		if (!warned && time_after(now, start + 5 * HZ) &&
3406 		    (deadline - now > 3 * HZ)) {
3407 			ata_link_printk(link, KERN_WARNING,
3408 				"link is slow to respond, please be patient "
3409 				"(ready=%d)\n", tmp);
3410 			warned = 1;
3411 		}
3412 
3413 		ata_msleep(link->ap, 50);
3414 	}
3415 }
3416 
3417 /**
3418  *	ata_wait_after_reset - wait for link to become ready after reset
3419  *	@link: link to be waited on
3420  *	@deadline: deadline jiffies for the operation
3421  *	@check_ready: callback to check link readiness
3422  *
3423  *	Wait for @link to become ready after reset.
3424  *
3425  *	LOCKING:
3426  *	EH context.
3427  *
3428  *	RETURNS:
3429  *	0 if @linke is ready before @deadline; otherwise, -errno.
3430  */
3431 int ata_wait_after_reset(struct ata_link *link, unsigned long deadline,
3432 				int (*check_ready)(struct ata_link *link))
3433 {
3434 	ata_msleep(link->ap, ATA_WAIT_AFTER_RESET);
3435 
3436 	return ata_wait_ready(link, deadline, check_ready);
3437 }
3438 
3439 /**
3440  *	sata_link_debounce - debounce SATA phy status
3441  *	@link: ATA link to debounce SATA phy status for
3442  *	@params: timing parameters { interval, duratinon, timeout } in msec
3443  *	@deadline: deadline jiffies for the operation
3444  *
3445  *	Make sure SStatus of @link reaches stable state, determined by
3446  *	holding the same value where DET is not 1 for @duration polled
3447  *	every @interval, before @timeout.  Timeout constraints the
3448  *	beginning of the stable state.  Because DET gets stuck at 1 on
3449  *	some controllers after hot unplugging, this functions waits
3450  *	until timeout then returns 0 if DET is stable at 1.
3451  *
3452  *	@timeout is further limited by @deadline.  The sooner of the
3453  *	two is used.
3454  *
3455  *	LOCKING:
3456  *	Kernel thread context (may sleep)
3457  *
3458  *	RETURNS:
3459  *	0 on success, -errno on failure.
3460  */
3461 int sata_link_debounce(struct ata_link *link, const unsigned long *params,
3462 		       unsigned long deadline)
3463 {
3464 	unsigned long interval = params[0];
3465 	unsigned long duration = params[1];
3466 	unsigned long last_jiffies, t;
3467 	u32 last, cur;
3468 	int rc;
3469 
3470 	t = ata_deadline(jiffies, params[2]);
3471 	if (time_before(t, deadline))
3472 		deadline = t;
3473 
3474 	if ((rc = sata_scr_read(link, SCR_STATUS, &cur)))
3475 		return rc;
3476 	cur &= 0xf;
3477 
3478 	last = cur;
3479 	last_jiffies = jiffies;
3480 
3481 	while (1) {
3482 		ata_msleep(link->ap, interval);
3483 		if ((rc = sata_scr_read(link, SCR_STATUS, &cur)))
3484 			return rc;
3485 		cur &= 0xf;
3486 
3487 		/* DET stable? */
3488 		if (cur == last) {
3489 			if (cur == 1 && time_before(jiffies, deadline))
3490 				continue;
3491 			if (time_after(jiffies,
3492 				       ata_deadline(last_jiffies, duration)))
3493 				return 0;
3494 			continue;
3495 		}
3496 
3497 		/* unstable, start over */
3498 		last = cur;
3499 		last_jiffies = jiffies;
3500 
3501 		/* Check deadline.  If debouncing failed, return
3502 		 * -EPIPE to tell upper layer to lower link speed.
3503 		 */
3504 		if (time_after(jiffies, deadline))
3505 			return -EPIPE;
3506 	}
3507 }
3508 
3509 /**
3510  *	sata_link_resume - resume SATA link
3511  *	@link: ATA link to resume SATA
3512  *	@params: timing parameters { interval, duratinon, timeout } in msec
3513  *	@deadline: deadline jiffies for the operation
3514  *
3515  *	Resume SATA phy @link and debounce it.
3516  *
3517  *	LOCKING:
3518  *	Kernel thread context (may sleep)
3519  *
3520  *	RETURNS:
3521  *	0 on success, -errno on failure.
3522  */
3523 int sata_link_resume(struct ata_link *link, const unsigned long *params,
3524 		     unsigned long deadline)
3525 {
3526 	int tries = ATA_LINK_RESUME_TRIES;
3527 	u32 scontrol, serror;
3528 	int rc;
3529 
3530 	if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3531 		return rc;
3532 
3533 	/*
3534 	 * Writes to SControl sometimes get ignored under certain
3535 	 * controllers (ata_piix SIDPR).  Make sure DET actually is
3536 	 * cleared.
3537 	 */
3538 	do {
3539 		scontrol = (scontrol & 0x0f0) | 0x300;
3540 		if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
3541 			return rc;
3542 		/*
3543 		 * Some PHYs react badly if SStatus is pounded
3544 		 * immediately after resuming.  Delay 200ms before
3545 		 * debouncing.
3546 		 */
3547 		ata_msleep(link->ap, 200);
3548 
3549 		/* is SControl restored correctly? */
3550 		if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3551 			return rc;
3552 	} while ((scontrol & 0xf0f) != 0x300 && --tries);
3553 
3554 	if ((scontrol & 0xf0f) != 0x300) {
3555 		ata_link_printk(link, KERN_ERR,
3556 				"failed to resume link (SControl %X)\n",
3557 				scontrol);
3558 		return 0;
3559 	}
3560 
3561 	if (tries < ATA_LINK_RESUME_TRIES)
3562 		ata_link_printk(link, KERN_WARNING,
3563 				"link resume succeeded after %d retries\n",
3564 				ATA_LINK_RESUME_TRIES - tries);
3565 
3566 	if ((rc = sata_link_debounce(link, params, deadline)))
3567 		return rc;
3568 
3569 	/* clear SError, some PHYs require this even for SRST to work */
3570 	if (!(rc = sata_scr_read(link, SCR_ERROR, &serror)))
3571 		rc = sata_scr_write(link, SCR_ERROR, serror);
3572 
3573 	return rc != -EINVAL ? rc : 0;
3574 }
3575 
3576 /**
3577  *	sata_link_scr_lpm - manipulate SControl IPM and SPM fields
3578  *	@link: ATA link to manipulate SControl for
3579  *	@policy: LPM policy to configure
3580  *	@spm_wakeup: initiate LPM transition to active state
3581  *
3582  *	Manipulate the IPM field of the SControl register of @link
3583  *	according to @policy.  If @policy is ATA_LPM_MAX_POWER and
3584  *	@spm_wakeup is %true, the SPM field is manipulated to wake up
3585  *	the link.  This function also clears PHYRDY_CHG before
3586  *	returning.
3587  *
3588  *	LOCKING:
3589  *	EH context.
3590  *
3591  *	RETURNS:
3592  *	0 on succes, -errno otherwise.
3593  */
3594 int sata_link_scr_lpm(struct ata_link *link, enum ata_lpm_policy policy,
3595 		      bool spm_wakeup)
3596 {
3597 	struct ata_eh_context *ehc = &link->eh_context;
3598 	bool woken_up = false;
3599 	u32 scontrol;
3600 	int rc;
3601 
3602 	rc = sata_scr_read(link, SCR_CONTROL, &scontrol);
3603 	if (rc)
3604 		return rc;
3605 
3606 	switch (policy) {
3607 	case ATA_LPM_MAX_POWER:
3608 		/* disable all LPM transitions */
3609 		scontrol |= (0x3 << 8);
3610 		/* initiate transition to active state */
3611 		if (spm_wakeup) {
3612 			scontrol |= (0x4 << 12);
3613 			woken_up = true;
3614 		}
3615 		break;
3616 	case ATA_LPM_MED_POWER:
3617 		/* allow LPM to PARTIAL */
3618 		scontrol &= ~(0x1 << 8);
3619 		scontrol |= (0x2 << 8);
3620 		break;
3621 	case ATA_LPM_MIN_POWER:
3622 		/* no restrictions on LPM transitions */
3623 		scontrol &= ~(0x3 << 8);
3624 		break;
3625 	default:
3626 		WARN_ON(1);
3627 	}
3628 
3629 	rc = sata_scr_write(link, SCR_CONTROL, scontrol);
3630 	if (rc)
3631 		return rc;
3632 
3633 	/* give the link time to transit out of LPM state */
3634 	if (woken_up)
3635 		msleep(10);
3636 
3637 	/* clear PHYRDY_CHG from SError */
3638 	ehc->i.serror &= ~SERR_PHYRDY_CHG;
3639 	return sata_scr_write(link, SCR_ERROR, SERR_PHYRDY_CHG);
3640 }
3641 
3642 /**
3643  *	ata_std_prereset - prepare for reset
3644  *	@link: ATA link to be reset
3645  *	@deadline: deadline jiffies for the operation
3646  *
3647  *	@link is about to be reset.  Initialize it.  Failure from
3648  *	prereset makes libata abort whole reset sequence and give up
3649  *	that port, so prereset should be best-effort.  It does its
3650  *	best to prepare for reset sequence but if things go wrong, it
3651  *	should just whine, not fail.
3652  *
3653  *	LOCKING:
3654  *	Kernel thread context (may sleep)
3655  *
3656  *	RETURNS:
3657  *	0 on success, -errno otherwise.
3658  */
3659 int ata_std_prereset(struct ata_link *link, unsigned long deadline)
3660 {
3661 	struct ata_port *ap = link->ap;
3662 	struct ata_eh_context *ehc = &link->eh_context;
3663 	const unsigned long *timing = sata_ehc_deb_timing(ehc);
3664 	int rc;
3665 
3666 	/* if we're about to do hardreset, nothing more to do */
3667 	if (ehc->i.action & ATA_EH_HARDRESET)
3668 		return 0;
3669 
3670 	/* if SATA, resume link */
3671 	if (ap->flags & ATA_FLAG_SATA) {
3672 		rc = sata_link_resume(link, timing, deadline);
3673 		/* whine about phy resume failure but proceed */
3674 		if (rc && rc != -EOPNOTSUPP)
3675 			ata_link_printk(link, KERN_WARNING, "failed to resume "
3676 					"link for reset (errno=%d)\n", rc);
3677 	}
3678 
3679 	/* no point in trying softreset on offline link */
3680 	if (ata_phys_link_offline(link))
3681 		ehc->i.action &= ~ATA_EH_SOFTRESET;
3682 
3683 	return 0;
3684 }
3685 
3686 /**
3687  *	sata_link_hardreset - reset link via SATA phy reset
3688  *	@link: link to reset
3689  *	@timing: timing parameters { interval, duratinon, timeout } in msec
3690  *	@deadline: deadline jiffies for the operation
3691  *	@online: optional out parameter indicating link onlineness
3692  *	@check_ready: optional callback to check link readiness
3693  *
3694  *	SATA phy-reset @link using DET bits of SControl register.
3695  *	After hardreset, link readiness is waited upon using
3696  *	ata_wait_ready() if @check_ready is specified.  LLDs are
3697  *	allowed to not specify @check_ready and wait itself after this
3698  *	function returns.  Device classification is LLD's
3699  *	responsibility.
3700  *
3701  *	*@online is set to one iff reset succeeded and @link is online
3702  *	after reset.
3703  *
3704  *	LOCKING:
3705  *	Kernel thread context (may sleep)
3706  *
3707  *	RETURNS:
3708  *	0 on success, -errno otherwise.
3709  */
3710 int sata_link_hardreset(struct ata_link *link, const unsigned long *timing,
3711 			unsigned long deadline,
3712 			bool *online, int (*check_ready)(struct ata_link *))
3713 {
3714 	u32 scontrol;
3715 	int rc;
3716 
3717 	DPRINTK("ENTER\n");
3718 
3719 	if (online)
3720 		*online = false;
3721 
3722 	if (sata_set_spd_needed(link)) {
3723 		/* SATA spec says nothing about how to reconfigure
3724 		 * spd.  To be on the safe side, turn off phy during
3725 		 * reconfiguration.  This works for at least ICH7 AHCI
3726 		 * and Sil3124.
3727 		 */
3728 		if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3729 			goto out;
3730 
3731 		scontrol = (scontrol & 0x0f0) | 0x304;
3732 
3733 		if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
3734 			goto out;
3735 
3736 		sata_set_spd(link);
3737 	}
3738 
3739 	/* issue phy wake/reset */
3740 	if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3741 		goto out;
3742 
3743 	scontrol = (scontrol & 0x0f0) | 0x301;
3744 
3745 	if ((rc = sata_scr_write_flush(link, SCR_CONTROL, scontrol)))
3746 		goto out;
3747 
3748 	/* Couldn't find anything in SATA I/II specs, but AHCI-1.1
3749 	 * 10.4.2 says at least 1 ms.
3750 	 */
3751 	ata_msleep(link->ap, 1);
3752 
3753 	/* bring link back */
3754 	rc = sata_link_resume(link, timing, deadline);
3755 	if (rc)
3756 		goto out;
3757 	/* if link is offline nothing more to do */
3758 	if (ata_phys_link_offline(link))
3759 		goto out;
3760 
3761 	/* Link is online.  From this point, -ENODEV too is an error. */
3762 	if (online)
3763 		*online = true;
3764 
3765 	if (sata_pmp_supported(link->ap) && ata_is_host_link(link)) {
3766 		/* If PMP is supported, we have to do follow-up SRST.
3767 		 * Some PMPs don't send D2H Reg FIS after hardreset if
3768 		 * the first port is empty.  Wait only for
3769 		 * ATA_TMOUT_PMP_SRST_WAIT.
3770 		 */
3771 		if (check_ready) {
3772 			unsigned long pmp_deadline;
3773 
3774 			pmp_deadline = ata_deadline(jiffies,
3775 						    ATA_TMOUT_PMP_SRST_WAIT);
3776 			if (time_after(pmp_deadline, deadline))
3777 				pmp_deadline = deadline;
3778 			ata_wait_ready(link, pmp_deadline, check_ready);
3779 		}
3780 		rc = -EAGAIN;
3781 		goto out;
3782 	}
3783 
3784 	rc = 0;
3785 	if (check_ready)
3786 		rc = ata_wait_ready(link, deadline, check_ready);
3787  out:
3788 	if (rc && rc != -EAGAIN) {
3789 		/* online is set iff link is online && reset succeeded */
3790 		if (online)
3791 			*online = false;
3792 		ata_link_printk(link, KERN_ERR,
3793 				"COMRESET failed (errno=%d)\n", rc);
3794 	}
3795 	DPRINTK("EXIT, rc=%d\n", rc);
3796 	return rc;
3797 }
3798 
3799 /**
3800  *	sata_std_hardreset - COMRESET w/o waiting or classification
3801  *	@link: link to reset
3802  *	@class: resulting class of attached device
3803  *	@deadline: deadline jiffies for the operation
3804  *
3805  *	Standard SATA COMRESET w/o waiting or classification.
3806  *
3807  *	LOCKING:
3808  *	Kernel thread context (may sleep)
3809  *
3810  *	RETURNS:
3811  *	0 if link offline, -EAGAIN if link online, -errno on errors.
3812  */
3813 int sata_std_hardreset(struct ata_link *link, unsigned int *class,
3814 		       unsigned long deadline)
3815 {
3816 	const unsigned long *timing = sata_ehc_deb_timing(&link->eh_context);
3817 	bool online;
3818 	int rc;
3819 
3820 	/* do hardreset */
3821 	rc = sata_link_hardreset(link, timing, deadline, &online, NULL);
3822 	return online ? -EAGAIN : rc;
3823 }
3824 
3825 /**
3826  *	ata_std_postreset - standard postreset callback
3827  *	@link: the target ata_link
3828  *	@classes: classes of attached devices
3829  *
3830  *	This function is invoked after a successful reset.  Note that
3831  *	the device might have been reset more than once using
3832  *	different reset methods before postreset is invoked.
3833  *
3834  *	LOCKING:
3835  *	Kernel thread context (may sleep)
3836  */
3837 void ata_std_postreset(struct ata_link *link, unsigned int *classes)
3838 {
3839 	u32 serror;
3840 
3841 	DPRINTK("ENTER\n");
3842 
3843 	/* reset complete, clear SError */
3844 	if (!sata_scr_read(link, SCR_ERROR, &serror))
3845 		sata_scr_write(link, SCR_ERROR, serror);
3846 
3847 	/* print link status */
3848 	sata_print_link_status(link);
3849 
3850 	DPRINTK("EXIT\n");
3851 }
3852 
3853 /**
3854  *	ata_dev_same_device - Determine whether new ID matches configured device
3855  *	@dev: device to compare against
3856  *	@new_class: class of the new device
3857  *	@new_id: IDENTIFY page of the new device
3858  *
3859  *	Compare @new_class and @new_id against @dev and determine
3860  *	whether @dev is the device indicated by @new_class and
3861  *	@new_id.
3862  *
3863  *	LOCKING:
3864  *	None.
3865  *
3866  *	RETURNS:
3867  *	1 if @dev matches @new_class and @new_id, 0 otherwise.
3868  */
3869 static int ata_dev_same_device(struct ata_device *dev, unsigned int new_class,
3870 			       const u16 *new_id)
3871 {
3872 	const u16 *old_id = dev->id;
3873 	unsigned char model[2][ATA_ID_PROD_LEN + 1];
3874 	unsigned char serial[2][ATA_ID_SERNO_LEN + 1];
3875 
3876 	if (dev->class != new_class) {
3877 		ata_dev_printk(dev, KERN_INFO, "class mismatch %d != %d\n",
3878 			       dev->class, new_class);
3879 		return 0;
3880 	}
3881 
3882 	ata_id_c_string(old_id, model[0], ATA_ID_PROD, sizeof(model[0]));
3883 	ata_id_c_string(new_id, model[1], ATA_ID_PROD, sizeof(model[1]));
3884 	ata_id_c_string(old_id, serial[0], ATA_ID_SERNO, sizeof(serial[0]));
3885 	ata_id_c_string(new_id, serial[1], ATA_ID_SERNO, sizeof(serial[1]));
3886 
3887 	if (strcmp(model[0], model[1])) {
3888 		ata_dev_printk(dev, KERN_INFO, "model number mismatch "
3889 			       "'%s' != '%s'\n", model[0], model[1]);
3890 		return 0;
3891 	}
3892 
3893 	if (strcmp(serial[0], serial[1])) {
3894 		ata_dev_printk(dev, KERN_INFO, "serial number mismatch "
3895 			       "'%s' != '%s'\n", serial[0], serial[1]);
3896 		return 0;
3897 	}
3898 
3899 	return 1;
3900 }
3901 
3902 /**
3903  *	ata_dev_reread_id - Re-read IDENTIFY data
3904  *	@dev: target ATA device
3905  *	@readid_flags: read ID flags
3906  *
3907  *	Re-read IDENTIFY page and make sure @dev is still attached to
3908  *	the port.
3909  *
3910  *	LOCKING:
3911  *	Kernel thread context (may sleep)
3912  *
3913  *	RETURNS:
3914  *	0 on success, negative errno otherwise
3915  */
3916 int ata_dev_reread_id(struct ata_device *dev, unsigned int readid_flags)
3917 {
3918 	unsigned int class = dev->class;
3919 	u16 *id = (void *)dev->link->ap->sector_buf;
3920 	int rc;
3921 
3922 	/* read ID data */
3923 	rc = ata_dev_read_id(dev, &class, readid_flags, id);
3924 	if (rc)
3925 		return rc;
3926 
3927 	/* is the device still there? */
3928 	if (!ata_dev_same_device(dev, class, id))
3929 		return -ENODEV;
3930 
3931 	memcpy(dev->id, id, sizeof(id[0]) * ATA_ID_WORDS);
3932 	return 0;
3933 }
3934 
3935 /**
3936  *	ata_dev_revalidate - Revalidate ATA device
3937  *	@dev: device to revalidate
3938  *	@new_class: new class code
3939  *	@readid_flags: read ID flags
3940  *
3941  *	Re-read IDENTIFY page, make sure @dev is still attached to the
3942  *	port and reconfigure it according to the new IDENTIFY page.
3943  *
3944  *	LOCKING:
3945  *	Kernel thread context (may sleep)
3946  *
3947  *	RETURNS:
3948  *	0 on success, negative errno otherwise
3949  */
3950 int ata_dev_revalidate(struct ata_device *dev, unsigned int new_class,
3951 		       unsigned int readid_flags)
3952 {
3953 	u64 n_sectors = dev->n_sectors;
3954 	u64 n_native_sectors = dev->n_native_sectors;
3955 	int rc;
3956 
3957 	if (!ata_dev_enabled(dev))
3958 		return -ENODEV;
3959 
3960 	/* fail early if !ATA && !ATAPI to avoid issuing [P]IDENTIFY to PMP */
3961 	if (ata_class_enabled(new_class) &&
3962 	    new_class != ATA_DEV_ATA &&
3963 	    new_class != ATA_DEV_ATAPI &&
3964 	    new_class != ATA_DEV_SEMB) {
3965 		ata_dev_printk(dev, KERN_INFO, "class mismatch %u != %u\n",
3966 			       dev->class, new_class);
3967 		rc = -ENODEV;
3968 		goto fail;
3969 	}
3970 
3971 	/* re-read ID */
3972 	rc = ata_dev_reread_id(dev, readid_flags);
3973 	if (rc)
3974 		goto fail;
3975 
3976 	/* configure device according to the new ID */
3977 	rc = ata_dev_configure(dev);
3978 	if (rc)
3979 		goto fail;
3980 
3981 	/* verify n_sectors hasn't changed */
3982 	if (dev->class != ATA_DEV_ATA || !n_sectors ||
3983 	    dev->n_sectors == n_sectors)
3984 		return 0;
3985 
3986 	/* n_sectors has changed */
3987 	ata_dev_printk(dev, KERN_WARNING, "n_sectors mismatch %llu != %llu\n",
3988 		       (unsigned long long)n_sectors,
3989 		       (unsigned long long)dev->n_sectors);
3990 
3991 	/*
3992 	 * Something could have caused HPA to be unlocked
3993 	 * involuntarily.  If n_native_sectors hasn't changed and the
3994 	 * new size matches it, keep the device.
3995 	 */
3996 	if (dev->n_native_sectors == n_native_sectors &&
3997 	    dev->n_sectors > n_sectors && dev->n_sectors == n_native_sectors) {
3998 		ata_dev_printk(dev, KERN_WARNING,
3999 			       "new n_sectors matches native, probably "
4000 			       "late HPA unlock, n_sectors updated\n");
4001 		/* use the larger n_sectors */
4002 		return 0;
4003 	}
4004 
4005 	/*
4006 	 * Some BIOSes boot w/o HPA but resume w/ HPA locked.  Try
4007 	 * unlocking HPA in those cases.
4008 	 *
4009 	 * https://bugzilla.kernel.org/show_bug.cgi?id=15396
4010 	 */
4011 	if (dev->n_native_sectors == n_native_sectors &&
4012 	    dev->n_sectors < n_sectors && n_sectors == n_native_sectors &&
4013 	    !(dev->horkage & ATA_HORKAGE_BROKEN_HPA)) {
4014 		ata_dev_printk(dev, KERN_WARNING,
4015 			       "old n_sectors matches native, probably "
4016 			       "late HPA lock, will try to unlock HPA\n");
4017 		/* try unlocking HPA */
4018 		dev->flags |= ATA_DFLAG_UNLOCK_HPA;
4019 		rc = -EIO;
4020 	} else
4021 		rc = -ENODEV;
4022 
4023 	/* restore original n_[native_]sectors and fail */
4024 	dev->n_native_sectors = n_native_sectors;
4025 	dev->n_sectors = n_sectors;
4026  fail:
4027 	ata_dev_printk(dev, KERN_ERR, "revalidation failed (errno=%d)\n", rc);
4028 	return rc;
4029 }
4030 
4031 struct ata_blacklist_entry {
4032 	const char *model_num;
4033 	const char *model_rev;
4034 	unsigned long horkage;
4035 };
4036 
4037 static const struct ata_blacklist_entry ata_device_blacklist [] = {
4038 	/* Devices with DMA related problems under Linux */
4039 	{ "WDC AC11000H",	NULL,		ATA_HORKAGE_NODMA },
4040 	{ "WDC AC22100H",	NULL,		ATA_HORKAGE_NODMA },
4041 	{ "WDC AC32500H",	NULL,		ATA_HORKAGE_NODMA },
4042 	{ "WDC AC33100H",	NULL,		ATA_HORKAGE_NODMA },
4043 	{ "WDC AC31600H",	NULL,		ATA_HORKAGE_NODMA },
4044 	{ "WDC AC32100H",	"24.09P07",	ATA_HORKAGE_NODMA },
4045 	{ "WDC AC23200L",	"21.10N21",	ATA_HORKAGE_NODMA },
4046 	{ "Compaq CRD-8241B", 	NULL,		ATA_HORKAGE_NODMA },
4047 	{ "CRD-8400B",		NULL, 		ATA_HORKAGE_NODMA },
4048 	{ "CRD-848[02]B",	NULL,		ATA_HORKAGE_NODMA },
4049 	{ "CRD-84",		NULL,		ATA_HORKAGE_NODMA },
4050 	{ "SanDisk SDP3B",	NULL,		ATA_HORKAGE_NODMA },
4051 	{ "SanDisk SDP3B-64",	NULL,		ATA_HORKAGE_NODMA },
4052 	{ "SANYO CD-ROM CRD",	NULL,		ATA_HORKAGE_NODMA },
4053 	{ "HITACHI CDR-8",	NULL,		ATA_HORKAGE_NODMA },
4054 	{ "HITACHI CDR-8[34]35",NULL,		ATA_HORKAGE_NODMA },
4055 	{ "Toshiba CD-ROM XM-6202B", NULL,	ATA_HORKAGE_NODMA },
4056 	{ "TOSHIBA CD-ROM XM-1702BC", NULL,	ATA_HORKAGE_NODMA },
4057 	{ "CD-532E-A", 		NULL,		ATA_HORKAGE_NODMA },
4058 	{ "E-IDE CD-ROM CR-840",NULL,		ATA_HORKAGE_NODMA },
4059 	{ "CD-ROM Drive/F5A",	NULL,		ATA_HORKAGE_NODMA },
4060 	{ "WPI CDD-820", 	NULL,		ATA_HORKAGE_NODMA },
4061 	{ "SAMSUNG CD-ROM SC-148C", NULL,	ATA_HORKAGE_NODMA },
4062 	{ "SAMSUNG CD-ROM SC",	NULL,		ATA_HORKAGE_NODMA },
4063 	{ "ATAPI CD-ROM DRIVE 40X MAXIMUM",NULL,ATA_HORKAGE_NODMA },
4064 	{ "_NEC DV5800A", 	NULL,		ATA_HORKAGE_NODMA },
4065 	{ "SAMSUNG CD-ROM SN-124", "N001",	ATA_HORKAGE_NODMA },
4066 	{ "Seagate STT20000A", NULL,		ATA_HORKAGE_NODMA },
4067 	/* Odd clown on sil3726/4726 PMPs */
4068 	{ "Config  Disk",	NULL,		ATA_HORKAGE_DISABLE },
4069 
4070 	/* Weird ATAPI devices */
4071 	{ "TORiSAN DVD-ROM DRD-N216", NULL,	ATA_HORKAGE_MAX_SEC_128 },
4072 	{ "QUANTUM DAT    DAT72-000", NULL,	ATA_HORKAGE_ATAPI_MOD16_DMA },
4073 
4074 	/* Devices we expect to fail diagnostics */
4075 
4076 	/* Devices where NCQ should be avoided */
4077 	/* NCQ is slow */
4078 	{ "WDC WD740ADFD-00",	NULL,		ATA_HORKAGE_NONCQ },
4079 	{ "WDC WD740ADFD-00NLR1", NULL,		ATA_HORKAGE_NONCQ, },
4080 	/* http://thread.gmane.org/gmane.linux.ide/14907 */
4081 	{ "FUJITSU MHT2060BH",	NULL,		ATA_HORKAGE_NONCQ },
4082 	/* NCQ is broken */
4083 	{ "Maxtor *",		"BANC*",	ATA_HORKAGE_NONCQ },
4084 	{ "Maxtor 7V300F0",	"VA111630",	ATA_HORKAGE_NONCQ },
4085 	{ "ST380817AS",		"3.42",		ATA_HORKAGE_NONCQ },
4086 	{ "ST3160023AS",	"3.42",		ATA_HORKAGE_NONCQ },
4087 	{ "OCZ CORE_SSD",	"02.10104",	ATA_HORKAGE_NONCQ },
4088 
4089 	/* Seagate NCQ + FLUSH CACHE firmware bug */
4090 	{ "ST31500341AS",	"SD1[5-9]",	ATA_HORKAGE_NONCQ |
4091 						ATA_HORKAGE_FIRMWARE_WARN },
4092 
4093 	{ "ST31000333AS",	"SD1[5-9]",	ATA_HORKAGE_NONCQ |
4094 						ATA_HORKAGE_FIRMWARE_WARN },
4095 
4096 	{ "ST3640[36]23AS",	"SD1[5-9]",	ATA_HORKAGE_NONCQ |
4097 						ATA_HORKAGE_FIRMWARE_WARN },
4098 
4099 	{ "ST3320[68]13AS",	"SD1[5-9]",	ATA_HORKAGE_NONCQ |
4100 						ATA_HORKAGE_FIRMWARE_WARN },
4101 
4102 	/* Blacklist entries taken from Silicon Image 3124/3132
4103 	   Windows driver .inf file - also several Linux problem reports */
4104 	{ "HTS541060G9SA00",    "MB3OC60D",     ATA_HORKAGE_NONCQ, },
4105 	{ "HTS541080G9SA00",    "MB4OC60D",     ATA_HORKAGE_NONCQ, },
4106 	{ "HTS541010G9SA00",    "MBZOC60D",     ATA_HORKAGE_NONCQ, },
4107 
4108 	/* https://bugzilla.kernel.org/show_bug.cgi?id=15573 */
4109 	{ "C300-CTFDDAC128MAG",	"0001",		ATA_HORKAGE_NONCQ, },
4110 
4111 	/* devices which puke on READ_NATIVE_MAX */
4112 	{ "HDS724040KLSA80",	"KFAOA20N",	ATA_HORKAGE_BROKEN_HPA, },
4113 	{ "WDC WD3200JD-00KLB0", "WD-WCAMR1130137", ATA_HORKAGE_BROKEN_HPA },
4114 	{ "WDC WD2500JD-00HBB0", "WD-WMAL71490727", ATA_HORKAGE_BROKEN_HPA },
4115 	{ "MAXTOR 6L080L4",	"A93.0500",	ATA_HORKAGE_BROKEN_HPA },
4116 
4117 	/* this one allows HPA unlocking but fails IOs on the area */
4118 	{ "OCZ-VERTEX",		    "1.30",	ATA_HORKAGE_BROKEN_HPA },
4119 
4120 	/* Devices which report 1 sector over size HPA */
4121 	{ "ST340823A",		NULL,		ATA_HORKAGE_HPA_SIZE, },
4122 	{ "ST320413A",		NULL,		ATA_HORKAGE_HPA_SIZE, },
4123 	{ "ST310211A",		NULL,		ATA_HORKAGE_HPA_SIZE, },
4124 
4125 	/* Devices which get the IVB wrong */
4126 	{ "QUANTUM FIREBALLlct10 05", "A03.0900", ATA_HORKAGE_IVB, },
4127 	/* Maybe we should just blacklist TSSTcorp... */
4128 	{ "TSSTcorp CDDVDW SH-S202[HJN]", "SB0[01]",  ATA_HORKAGE_IVB, },
4129 
4130 	/* Devices that do not need bridging limits applied */
4131 	{ "MTRON MSP-SATA*",		NULL,	ATA_HORKAGE_BRIDGE_OK, },
4132 
4133 	/* Devices which aren't very happy with higher link speeds */
4134 	{ "WD My Book",			NULL,	ATA_HORKAGE_1_5_GBPS, },
4135 
4136 	/*
4137 	 * Devices which choke on SETXFER.  Applies only if both the
4138 	 * device and controller are SATA.
4139 	 */
4140 	{ "PIONEER DVD-RW  DVRTD08",	"1.00",	ATA_HORKAGE_NOSETXFER },
4141 
4142 	/* End Marker */
4143 	{ }
4144 };
4145 
4146 /**
4147  *	glob_match - match a text string against a glob-style pattern
4148  *	@text: the string to be examined
4149  *	@pattern: the glob-style pattern to be matched against
4150  *
4151  *	Either/both of text and pattern can be empty strings.
4152  *
4153  *	Match text against a glob-style pattern, with wildcards and simple sets:
4154  *
4155  *		?	matches any single character.
4156  *		*	matches any run of characters.
4157  *		[xyz]	matches a single character from the set: x, y, or z.
4158  *		[a-d]	matches a single character from the range: a, b, c, or d.
4159  *		[a-d0-9] matches a single character from either range.
4160  *
4161  *	The special characters ?, [, -, or *, can be matched using a set, eg. [*]
4162  *	Behaviour with malformed patterns is undefined, though generally reasonable.
4163  *
4164  *	Sample patterns:  "SD1?",  "SD1[0-5]",  "*R0",  "SD*1?[012]*xx"
4165  *
4166  *	This function uses one level of recursion per '*' in pattern.
4167  *	Since it calls _nothing_ else, and has _no_ explicit local variables,
4168  *	this will not cause stack problems for any reasonable use here.
4169  *
4170  *	RETURNS:
4171  *	0 on match, 1 otherwise.
4172  */
4173 static int glob_match (const char *text, const char *pattern)
4174 {
4175 	do {
4176 		/* Match single character or a '?' wildcard */
4177 		if (*text == *pattern || *pattern == '?') {
4178 			if (!*pattern++)
4179 				return 0;  /* End of both strings: match */
4180 		} else {
4181 			/* Match single char against a '[' bracketed ']' pattern set */
4182 			if (!*text || *pattern != '[')
4183 				break;  /* Not a pattern set */
4184 			while (*++pattern && *pattern != ']' && *text != *pattern) {
4185 				if (*pattern == '-' && *(pattern - 1) != '[')
4186 					if (*text > *(pattern - 1) && *text < *(pattern + 1)) {
4187 						++pattern;
4188 						break;
4189 					}
4190 			}
4191 			if (!*pattern || *pattern == ']')
4192 				return 1;  /* No match */
4193 			while (*pattern && *pattern++ != ']');
4194 		}
4195 	} while (*++text && *pattern);
4196 
4197 	/* Match any run of chars against a '*' wildcard */
4198 	if (*pattern == '*') {
4199 		if (!*++pattern)
4200 			return 0;  /* Match: avoid recursion at end of pattern */
4201 		/* Loop to handle additional pattern chars after the wildcard */
4202 		while (*text) {
4203 			if (glob_match(text, pattern) == 0)
4204 				return 0;  /* Remainder matched */
4205 			++text;  /* Absorb (match) this char and try again */
4206 		}
4207 	}
4208 	if (!*text && !*pattern)
4209 		return 0;  /* End of both strings: match */
4210 	return 1;  /* No match */
4211 }
4212 
4213 static unsigned long ata_dev_blacklisted(const struct ata_device *dev)
4214 {
4215 	unsigned char model_num[ATA_ID_PROD_LEN + 1];
4216 	unsigned char model_rev[ATA_ID_FW_REV_LEN + 1];
4217 	const struct ata_blacklist_entry *ad = ata_device_blacklist;
4218 
4219 	ata_id_c_string(dev->id, model_num, ATA_ID_PROD, sizeof(model_num));
4220 	ata_id_c_string(dev->id, model_rev, ATA_ID_FW_REV, sizeof(model_rev));
4221 
4222 	while (ad->model_num) {
4223 		if (!glob_match(model_num, ad->model_num)) {
4224 			if (ad->model_rev == NULL)
4225 				return ad->horkage;
4226 			if (!glob_match(model_rev, ad->model_rev))
4227 				return ad->horkage;
4228 		}
4229 		ad++;
4230 	}
4231 	return 0;
4232 }
4233 
4234 static int ata_dma_blacklisted(const struct ata_device *dev)
4235 {
4236 	/* We don't support polling DMA.
4237 	 * DMA blacklist those ATAPI devices with CDB-intr (and use PIO)
4238 	 * if the LLDD handles only interrupts in the HSM_ST_LAST state.
4239 	 */
4240 	if ((dev->link->ap->flags & ATA_FLAG_PIO_POLLING) &&
4241 	    (dev->flags & ATA_DFLAG_CDB_INTR))
4242 		return 1;
4243 	return (dev->horkage & ATA_HORKAGE_NODMA) ? 1 : 0;
4244 }
4245 
4246 /**
4247  *	ata_is_40wire		-	check drive side detection
4248  *	@dev: device
4249  *
4250  *	Perform drive side detection decoding, allowing for device vendors
4251  *	who can't follow the documentation.
4252  */
4253 
4254 static int ata_is_40wire(struct ata_device *dev)
4255 {
4256 	if (dev->horkage & ATA_HORKAGE_IVB)
4257 		return ata_drive_40wire_relaxed(dev->id);
4258 	return ata_drive_40wire(dev->id);
4259 }
4260 
4261 /**
4262  *	cable_is_40wire		-	40/80/SATA decider
4263  *	@ap: port to consider
4264  *
4265  *	This function encapsulates the policy for speed management
4266  *	in one place. At the moment we don't cache the result but
4267  *	there is a good case for setting ap->cbl to the result when
4268  *	we are called with unknown cables (and figuring out if it
4269  *	impacts hotplug at all).
4270  *
4271  *	Return 1 if the cable appears to be 40 wire.
4272  */
4273 
4274 static int cable_is_40wire(struct ata_port *ap)
4275 {
4276 	struct ata_link *link;
4277 	struct ata_device *dev;
4278 
4279 	/* If the controller thinks we are 40 wire, we are. */
4280 	if (ap->cbl == ATA_CBL_PATA40)
4281 		return 1;
4282 
4283 	/* If the controller thinks we are 80 wire, we are. */
4284 	if (ap->cbl == ATA_CBL_PATA80 || ap->cbl == ATA_CBL_SATA)
4285 		return 0;
4286 
4287 	/* If the system is known to be 40 wire short cable (eg
4288 	 * laptop), then we allow 80 wire modes even if the drive
4289 	 * isn't sure.
4290 	 */
4291 	if (ap->cbl == ATA_CBL_PATA40_SHORT)
4292 		return 0;
4293 
4294 	/* If the controller doesn't know, we scan.
4295 	 *
4296 	 * Note: We look for all 40 wire detects at this point.  Any
4297 	 *       80 wire detect is taken to be 80 wire cable because
4298 	 * - in many setups only the one drive (slave if present) will
4299 	 *   give a valid detect
4300 	 * - if you have a non detect capable drive you don't want it
4301 	 *   to colour the choice
4302 	 */
4303 	ata_for_each_link(link, ap, EDGE) {
4304 		ata_for_each_dev(dev, link, ENABLED) {
4305 			if (!ata_is_40wire(dev))
4306 				return 0;
4307 		}
4308 	}
4309 	return 1;
4310 }
4311 
4312 /**
4313  *	ata_dev_xfermask - Compute supported xfermask of the given device
4314  *	@dev: Device to compute xfermask for
4315  *
4316  *	Compute supported xfermask of @dev and store it in
4317  *	dev->*_mask.  This function is responsible for applying all
4318  *	known limits including host controller limits, device
4319  *	blacklist, etc...
4320  *
4321  *	LOCKING:
4322  *	None.
4323  */
4324 static void ata_dev_xfermask(struct ata_device *dev)
4325 {
4326 	struct ata_link *link = dev->link;
4327 	struct ata_port *ap = link->ap;
4328 	struct ata_host *host = ap->host;
4329 	unsigned long xfer_mask;
4330 
4331 	/* controller modes available */
4332 	xfer_mask = ata_pack_xfermask(ap->pio_mask,
4333 				      ap->mwdma_mask, ap->udma_mask);
4334 
4335 	/* drive modes available */
4336 	xfer_mask &= ata_pack_xfermask(dev->pio_mask,
4337 				       dev->mwdma_mask, dev->udma_mask);
4338 	xfer_mask &= ata_id_xfermask(dev->id);
4339 
4340 	/*
4341 	 *	CFA Advanced TrueIDE timings are not allowed on a shared
4342 	 *	cable
4343 	 */
4344 	if (ata_dev_pair(dev)) {
4345 		/* No PIO5 or PIO6 */
4346 		xfer_mask &= ~(0x03 << (ATA_SHIFT_PIO + 5));
4347 		/* No MWDMA3 or MWDMA 4 */
4348 		xfer_mask &= ~(0x03 << (ATA_SHIFT_MWDMA + 3));
4349 	}
4350 
4351 	if (ata_dma_blacklisted(dev)) {
4352 		xfer_mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA);
4353 		ata_dev_printk(dev, KERN_WARNING,
4354 			       "device is on DMA blacklist, disabling DMA\n");
4355 	}
4356 
4357 	if ((host->flags & ATA_HOST_SIMPLEX) &&
4358 	    host->simplex_claimed && host->simplex_claimed != ap) {
4359 		xfer_mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA);
4360 		ata_dev_printk(dev, KERN_WARNING, "simplex DMA is claimed by "
4361 			       "other device, disabling DMA\n");
4362 	}
4363 
4364 	if (ap->flags & ATA_FLAG_NO_IORDY)
4365 		xfer_mask &= ata_pio_mask_no_iordy(dev);
4366 
4367 	if (ap->ops->mode_filter)
4368 		xfer_mask = ap->ops->mode_filter(dev, xfer_mask);
4369 
4370 	/* Apply cable rule here.  Don't apply it early because when
4371 	 * we handle hot plug the cable type can itself change.
4372 	 * Check this last so that we know if the transfer rate was
4373 	 * solely limited by the cable.
4374 	 * Unknown or 80 wire cables reported host side are checked
4375 	 * drive side as well. Cases where we know a 40wire cable
4376 	 * is used safely for 80 are not checked here.
4377 	 */
4378 	if (xfer_mask & (0xF8 << ATA_SHIFT_UDMA))
4379 		/* UDMA/44 or higher would be available */
4380 		if (cable_is_40wire(ap)) {
4381 			ata_dev_printk(dev, KERN_WARNING,
4382 				 "limited to UDMA/33 due to 40-wire cable\n");
4383 			xfer_mask &= ~(0xF8 << ATA_SHIFT_UDMA);
4384 		}
4385 
4386 	ata_unpack_xfermask(xfer_mask, &dev->pio_mask,
4387 			    &dev->mwdma_mask, &dev->udma_mask);
4388 }
4389 
4390 /**
4391  *	ata_dev_set_xfermode - Issue SET FEATURES - XFER MODE command
4392  *	@dev: Device to which command will be sent
4393  *
4394  *	Issue SET FEATURES - XFER MODE command to device @dev
4395  *	on port @ap.
4396  *
4397  *	LOCKING:
4398  *	PCI/etc. bus probe sem.
4399  *
4400  *	RETURNS:
4401  *	0 on success, AC_ERR_* mask otherwise.
4402  */
4403 
4404 static unsigned int ata_dev_set_xfermode(struct ata_device *dev)
4405 {
4406 	struct ata_taskfile tf;
4407 	unsigned int err_mask;
4408 
4409 	/* set up set-features taskfile */
4410 	DPRINTK("set features - xfer mode\n");
4411 
4412 	/* Some controllers and ATAPI devices show flaky interrupt
4413 	 * behavior after setting xfer mode.  Use polling instead.
4414 	 */
4415 	ata_tf_init(dev, &tf);
4416 	tf.command = ATA_CMD_SET_FEATURES;
4417 	tf.feature = SETFEATURES_XFER;
4418 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE | ATA_TFLAG_POLLING;
4419 	tf.protocol = ATA_PROT_NODATA;
4420 	/* If we are using IORDY we must send the mode setting command */
4421 	if (ata_pio_need_iordy(dev))
4422 		tf.nsect = dev->xfer_mode;
4423 	/* If the device has IORDY and the controller does not - turn it off */
4424  	else if (ata_id_has_iordy(dev->id))
4425 		tf.nsect = 0x01;
4426 	else /* In the ancient relic department - skip all of this */
4427 		return 0;
4428 
4429 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
4430 
4431 	DPRINTK("EXIT, err_mask=%x\n", err_mask);
4432 	return err_mask;
4433 }
4434 
4435 /**
4436  *	ata_dev_set_feature - Issue SET FEATURES - SATA FEATURES
4437  *	@dev: Device to which command will be sent
4438  *	@enable: Whether to enable or disable the feature
4439  *	@feature: The sector count represents the feature to set
4440  *
4441  *	Issue SET FEATURES - SATA FEATURES command to device @dev
4442  *	on port @ap with sector count
4443  *
4444  *	LOCKING:
4445  *	PCI/etc. bus probe sem.
4446  *
4447  *	RETURNS:
4448  *	0 on success, AC_ERR_* mask otherwise.
4449  */
4450 unsigned int ata_dev_set_feature(struct ata_device *dev, u8 enable, u8 feature)
4451 {
4452 	struct ata_taskfile tf;
4453 	unsigned int err_mask;
4454 
4455 	/* set up set-features taskfile */
4456 	DPRINTK("set features - SATA features\n");
4457 
4458 	ata_tf_init(dev, &tf);
4459 	tf.command = ATA_CMD_SET_FEATURES;
4460 	tf.feature = enable;
4461 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
4462 	tf.protocol = ATA_PROT_NODATA;
4463 	tf.nsect = feature;
4464 
4465 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
4466 
4467 	DPRINTK("EXIT, err_mask=%x\n", err_mask);
4468 	return err_mask;
4469 }
4470 
4471 /**
4472  *	ata_dev_init_params - Issue INIT DEV PARAMS command
4473  *	@dev: Device to which command will be sent
4474  *	@heads: Number of heads (taskfile parameter)
4475  *	@sectors: Number of sectors (taskfile parameter)
4476  *
4477  *	LOCKING:
4478  *	Kernel thread context (may sleep)
4479  *
4480  *	RETURNS:
4481  *	0 on success, AC_ERR_* mask otherwise.
4482  */
4483 static unsigned int ata_dev_init_params(struct ata_device *dev,
4484 					u16 heads, u16 sectors)
4485 {
4486 	struct ata_taskfile tf;
4487 	unsigned int err_mask;
4488 
4489 	/* Number of sectors per track 1-255. Number of heads 1-16 */
4490 	if (sectors < 1 || sectors > 255 || heads < 1 || heads > 16)
4491 		return AC_ERR_INVALID;
4492 
4493 	/* set up init dev params taskfile */
4494 	DPRINTK("init dev params \n");
4495 
4496 	ata_tf_init(dev, &tf);
4497 	tf.command = ATA_CMD_INIT_DEV_PARAMS;
4498 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
4499 	tf.protocol = ATA_PROT_NODATA;
4500 	tf.nsect = sectors;
4501 	tf.device |= (heads - 1) & 0x0f; /* max head = num. of heads - 1 */
4502 
4503 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
4504 	/* A clean abort indicates an original or just out of spec drive
4505 	   and we should continue as we issue the setup based on the
4506 	   drive reported working geometry */
4507 	if (err_mask == AC_ERR_DEV && (tf.feature & ATA_ABORTED))
4508 		err_mask = 0;
4509 
4510 	DPRINTK("EXIT, err_mask=%x\n", err_mask);
4511 	return err_mask;
4512 }
4513 
4514 /**
4515  *	ata_sg_clean - Unmap DMA memory associated with command
4516  *	@qc: Command containing DMA memory to be released
4517  *
4518  *	Unmap all mapped DMA memory associated with this command.
4519  *
4520  *	LOCKING:
4521  *	spin_lock_irqsave(host lock)
4522  */
4523 void ata_sg_clean(struct ata_queued_cmd *qc)
4524 {
4525 	struct ata_port *ap = qc->ap;
4526 	struct scatterlist *sg = qc->sg;
4527 	int dir = qc->dma_dir;
4528 
4529 	WARN_ON_ONCE(sg == NULL);
4530 
4531 	VPRINTK("unmapping %u sg elements\n", qc->n_elem);
4532 
4533 	if (qc->n_elem)
4534 		dma_unmap_sg(ap->dev, sg, qc->orig_n_elem, dir);
4535 
4536 	qc->flags &= ~ATA_QCFLAG_DMAMAP;
4537 	qc->sg = NULL;
4538 }
4539 
4540 /**
4541  *	atapi_check_dma - Check whether ATAPI DMA can be supported
4542  *	@qc: Metadata associated with taskfile to check
4543  *
4544  *	Allow low-level driver to filter ATA PACKET commands, returning
4545  *	a status indicating whether or not it is OK to use DMA for the
4546  *	supplied PACKET command.
4547  *
4548  *	LOCKING:
4549  *	spin_lock_irqsave(host lock)
4550  *
4551  *	RETURNS: 0 when ATAPI DMA can be used
4552  *               nonzero otherwise
4553  */
4554 int atapi_check_dma(struct ata_queued_cmd *qc)
4555 {
4556 	struct ata_port *ap = qc->ap;
4557 
4558 	/* Don't allow DMA if it isn't multiple of 16 bytes.  Quite a
4559 	 * few ATAPI devices choke on such DMA requests.
4560 	 */
4561 	if (!(qc->dev->horkage & ATA_HORKAGE_ATAPI_MOD16_DMA) &&
4562 	    unlikely(qc->nbytes & 15))
4563 		return 1;
4564 
4565 	if (ap->ops->check_atapi_dma)
4566 		return ap->ops->check_atapi_dma(qc);
4567 
4568 	return 0;
4569 }
4570 
4571 /**
4572  *	ata_std_qc_defer - Check whether a qc needs to be deferred
4573  *	@qc: ATA command in question
4574  *
4575  *	Non-NCQ commands cannot run with any other command, NCQ or
4576  *	not.  As upper layer only knows the queue depth, we are
4577  *	responsible for maintaining exclusion.  This function checks
4578  *	whether a new command @qc can be issued.
4579  *
4580  *	LOCKING:
4581  *	spin_lock_irqsave(host lock)
4582  *
4583  *	RETURNS:
4584  *	ATA_DEFER_* if deferring is needed, 0 otherwise.
4585  */
4586 int ata_std_qc_defer(struct ata_queued_cmd *qc)
4587 {
4588 	struct ata_link *link = qc->dev->link;
4589 
4590 	if (qc->tf.protocol == ATA_PROT_NCQ) {
4591 		if (!ata_tag_valid(link->active_tag))
4592 			return 0;
4593 	} else {
4594 		if (!ata_tag_valid(link->active_tag) && !link->sactive)
4595 			return 0;
4596 	}
4597 
4598 	return ATA_DEFER_LINK;
4599 }
4600 
4601 void ata_noop_qc_prep(struct ata_queued_cmd *qc) { }
4602 
4603 /**
4604  *	ata_sg_init - Associate command with scatter-gather table.
4605  *	@qc: Command to be associated
4606  *	@sg: Scatter-gather table.
4607  *	@n_elem: Number of elements in s/g table.
4608  *
4609  *	Initialize the data-related elements of queued_cmd @qc
4610  *	to point to a scatter-gather table @sg, containing @n_elem
4611  *	elements.
4612  *
4613  *	LOCKING:
4614  *	spin_lock_irqsave(host lock)
4615  */
4616 void ata_sg_init(struct ata_queued_cmd *qc, struct scatterlist *sg,
4617 		 unsigned int n_elem)
4618 {
4619 	qc->sg = sg;
4620 	qc->n_elem = n_elem;
4621 	qc->cursg = qc->sg;
4622 }
4623 
4624 /**
4625  *	ata_sg_setup - DMA-map the scatter-gather table associated with a command.
4626  *	@qc: Command with scatter-gather table to be mapped.
4627  *
4628  *	DMA-map the scatter-gather table associated with queued_cmd @qc.
4629  *
4630  *	LOCKING:
4631  *	spin_lock_irqsave(host lock)
4632  *
4633  *	RETURNS:
4634  *	Zero on success, negative on error.
4635  *
4636  */
4637 static int ata_sg_setup(struct ata_queued_cmd *qc)
4638 {
4639 	struct ata_port *ap = qc->ap;
4640 	unsigned int n_elem;
4641 
4642 	VPRINTK("ENTER, ata%u\n", ap->print_id);
4643 
4644 	n_elem = dma_map_sg(ap->dev, qc->sg, qc->n_elem, qc->dma_dir);
4645 	if (n_elem < 1)
4646 		return -1;
4647 
4648 	DPRINTK("%d sg elements mapped\n", n_elem);
4649 	qc->orig_n_elem = qc->n_elem;
4650 	qc->n_elem = n_elem;
4651 	qc->flags |= ATA_QCFLAG_DMAMAP;
4652 
4653 	return 0;
4654 }
4655 
4656 /**
4657  *	swap_buf_le16 - swap halves of 16-bit words in place
4658  *	@buf:  Buffer to swap
4659  *	@buf_words:  Number of 16-bit words in buffer.
4660  *
4661  *	Swap halves of 16-bit words if needed to convert from
4662  *	little-endian byte order to native cpu byte order, or
4663  *	vice-versa.
4664  *
4665  *	LOCKING:
4666  *	Inherited from caller.
4667  */
4668 void swap_buf_le16(u16 *buf, unsigned int buf_words)
4669 {
4670 #ifdef __BIG_ENDIAN
4671 	unsigned int i;
4672 
4673 	for (i = 0; i < buf_words; i++)
4674 		buf[i] = le16_to_cpu(buf[i]);
4675 #endif /* __BIG_ENDIAN */
4676 }
4677 
4678 /**
4679  *	ata_qc_new - Request an available ATA command, for queueing
4680  *	@ap: target port
4681  *
4682  *	LOCKING:
4683  *	None.
4684  */
4685 
4686 static struct ata_queued_cmd *ata_qc_new(struct ata_port *ap)
4687 {
4688 	struct ata_queued_cmd *qc = NULL;
4689 	unsigned int i;
4690 
4691 	/* no command while frozen */
4692 	if (unlikely(ap->pflags & ATA_PFLAG_FROZEN))
4693 		return NULL;
4694 
4695 	/* the last tag is reserved for internal command. */
4696 	for (i = 0; i < ATA_MAX_QUEUE - 1; i++)
4697 		if (!test_and_set_bit(i, &ap->qc_allocated)) {
4698 			qc = __ata_qc_from_tag(ap, i);
4699 			break;
4700 		}
4701 
4702 	if (qc)
4703 		qc->tag = i;
4704 
4705 	return qc;
4706 }
4707 
4708 /**
4709  *	ata_qc_new_init - Request an available ATA command, and initialize it
4710  *	@dev: Device from whom we request an available command structure
4711  *
4712  *	LOCKING:
4713  *	None.
4714  */
4715 
4716 struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev)
4717 {
4718 	struct ata_port *ap = dev->link->ap;
4719 	struct ata_queued_cmd *qc;
4720 
4721 	qc = ata_qc_new(ap);
4722 	if (qc) {
4723 		qc->scsicmd = NULL;
4724 		qc->ap = ap;
4725 		qc->dev = dev;
4726 
4727 		ata_qc_reinit(qc);
4728 	}
4729 
4730 	return qc;
4731 }
4732 
4733 /**
4734  *	ata_qc_free - free unused ata_queued_cmd
4735  *	@qc: Command to complete
4736  *
4737  *	Designed to free unused ata_queued_cmd object
4738  *	in case something prevents using it.
4739  *
4740  *	LOCKING:
4741  *	spin_lock_irqsave(host lock)
4742  */
4743 void ata_qc_free(struct ata_queued_cmd *qc)
4744 {
4745 	struct ata_port *ap;
4746 	unsigned int tag;
4747 
4748 	WARN_ON_ONCE(qc == NULL); /* ata_qc_from_tag _might_ return NULL */
4749 	ap = qc->ap;
4750 
4751 	qc->flags = 0;
4752 	tag = qc->tag;
4753 	if (likely(ata_tag_valid(tag))) {
4754 		qc->tag = ATA_TAG_POISON;
4755 		clear_bit(tag, &ap->qc_allocated);
4756 	}
4757 }
4758 
4759 void __ata_qc_complete(struct ata_queued_cmd *qc)
4760 {
4761 	struct ata_port *ap;
4762 	struct ata_link *link;
4763 
4764 	WARN_ON_ONCE(qc == NULL); /* ata_qc_from_tag _might_ return NULL */
4765 	WARN_ON_ONCE(!(qc->flags & ATA_QCFLAG_ACTIVE));
4766 	ap = qc->ap;
4767 	link = qc->dev->link;
4768 
4769 	if (likely(qc->flags & ATA_QCFLAG_DMAMAP))
4770 		ata_sg_clean(qc);
4771 
4772 	/* command should be marked inactive atomically with qc completion */
4773 	if (qc->tf.protocol == ATA_PROT_NCQ) {
4774 		link->sactive &= ~(1 << qc->tag);
4775 		if (!link->sactive)
4776 			ap->nr_active_links--;
4777 	} else {
4778 		link->active_tag = ATA_TAG_POISON;
4779 		ap->nr_active_links--;
4780 	}
4781 
4782 	/* clear exclusive status */
4783 	if (unlikely(qc->flags & ATA_QCFLAG_CLEAR_EXCL &&
4784 		     ap->excl_link == link))
4785 		ap->excl_link = NULL;
4786 
4787 	/* atapi: mark qc as inactive to prevent the interrupt handler
4788 	 * from completing the command twice later, before the error handler
4789 	 * is called. (when rc != 0 and atapi request sense is needed)
4790 	 */
4791 	qc->flags &= ~ATA_QCFLAG_ACTIVE;
4792 	ap->qc_active &= ~(1 << qc->tag);
4793 
4794 	/* call completion callback */
4795 	qc->complete_fn(qc);
4796 }
4797 
4798 static void fill_result_tf(struct ata_queued_cmd *qc)
4799 {
4800 	struct ata_port *ap = qc->ap;
4801 
4802 	qc->result_tf.flags = qc->tf.flags;
4803 	ap->ops->qc_fill_rtf(qc);
4804 }
4805 
4806 static void ata_verify_xfer(struct ata_queued_cmd *qc)
4807 {
4808 	struct ata_device *dev = qc->dev;
4809 
4810 	if (ata_tag_internal(qc->tag))
4811 		return;
4812 
4813 	if (ata_is_nodata(qc->tf.protocol))
4814 		return;
4815 
4816 	if ((dev->mwdma_mask || dev->udma_mask) && ata_is_pio(qc->tf.protocol))
4817 		return;
4818 
4819 	dev->flags &= ~ATA_DFLAG_DUBIOUS_XFER;
4820 }
4821 
4822 /**
4823  *	ata_qc_complete - Complete an active ATA command
4824  *	@qc: Command to complete
4825  *
4826  *	Indicate to the mid and upper layers that an ATA command has
4827  *	completed, with either an ok or not-ok status.
4828  *
4829  *	Refrain from calling this function multiple times when
4830  *	successfully completing multiple NCQ commands.
4831  *	ata_qc_complete_multiple() should be used instead, which will
4832  *	properly update IRQ expect state.
4833  *
4834  *	LOCKING:
4835  *	spin_lock_irqsave(host lock)
4836  */
4837 void ata_qc_complete(struct ata_queued_cmd *qc)
4838 {
4839 	struct ata_port *ap = qc->ap;
4840 
4841 	/* XXX: New EH and old EH use different mechanisms to
4842 	 * synchronize EH with regular execution path.
4843 	 *
4844 	 * In new EH, a failed qc is marked with ATA_QCFLAG_FAILED.
4845 	 * Normal execution path is responsible for not accessing a
4846 	 * failed qc.  libata core enforces the rule by returning NULL
4847 	 * from ata_qc_from_tag() for failed qcs.
4848 	 *
4849 	 * Old EH depends on ata_qc_complete() nullifying completion
4850 	 * requests if ATA_QCFLAG_EH_SCHEDULED is set.  Old EH does
4851 	 * not synchronize with interrupt handler.  Only PIO task is
4852 	 * taken care of.
4853 	 */
4854 	if (ap->ops->error_handler) {
4855 		struct ata_device *dev = qc->dev;
4856 		struct ata_eh_info *ehi = &dev->link->eh_info;
4857 
4858 		if (unlikely(qc->err_mask))
4859 			qc->flags |= ATA_QCFLAG_FAILED;
4860 
4861 		if (unlikely(qc->flags & ATA_QCFLAG_FAILED)) {
4862 			/* always fill result TF for failed qc */
4863 			fill_result_tf(qc);
4864 
4865 			if (!ata_tag_internal(qc->tag))
4866 				ata_qc_schedule_eh(qc);
4867 			else
4868 				__ata_qc_complete(qc);
4869 			return;
4870 		}
4871 
4872 		WARN_ON_ONCE(ap->pflags & ATA_PFLAG_FROZEN);
4873 
4874 		/* read result TF if requested */
4875 		if (qc->flags & ATA_QCFLAG_RESULT_TF)
4876 			fill_result_tf(qc);
4877 
4878 		/* Some commands need post-processing after successful
4879 		 * completion.
4880 		 */
4881 		switch (qc->tf.command) {
4882 		case ATA_CMD_SET_FEATURES:
4883 			if (qc->tf.feature != SETFEATURES_WC_ON &&
4884 			    qc->tf.feature != SETFEATURES_WC_OFF)
4885 				break;
4886 			/* fall through */
4887 		case ATA_CMD_INIT_DEV_PARAMS: /* CHS translation changed */
4888 		case ATA_CMD_SET_MULTI: /* multi_count changed */
4889 			/* revalidate device */
4890 			ehi->dev_action[dev->devno] |= ATA_EH_REVALIDATE;
4891 			ata_port_schedule_eh(ap);
4892 			break;
4893 
4894 		case ATA_CMD_SLEEP:
4895 			dev->flags |= ATA_DFLAG_SLEEPING;
4896 			break;
4897 		}
4898 
4899 		if (unlikely(dev->flags & ATA_DFLAG_DUBIOUS_XFER))
4900 			ata_verify_xfer(qc);
4901 
4902 		__ata_qc_complete(qc);
4903 	} else {
4904 		if (qc->flags & ATA_QCFLAG_EH_SCHEDULED)
4905 			return;
4906 
4907 		/* read result TF if failed or requested */
4908 		if (qc->err_mask || qc->flags & ATA_QCFLAG_RESULT_TF)
4909 			fill_result_tf(qc);
4910 
4911 		__ata_qc_complete(qc);
4912 	}
4913 }
4914 
4915 /**
4916  *	ata_qc_complete_multiple - Complete multiple qcs successfully
4917  *	@ap: port in question
4918  *	@qc_active: new qc_active mask
4919  *
4920  *	Complete in-flight commands.  This functions is meant to be
4921  *	called from low-level driver's interrupt routine to complete
4922  *	requests normally.  ap->qc_active and @qc_active is compared
4923  *	and commands are completed accordingly.
4924  *
4925  *	Always use this function when completing multiple NCQ commands
4926  *	from IRQ handlers instead of calling ata_qc_complete()
4927  *	multiple times to keep IRQ expect status properly in sync.
4928  *
4929  *	LOCKING:
4930  *	spin_lock_irqsave(host lock)
4931  *
4932  *	RETURNS:
4933  *	Number of completed commands on success, -errno otherwise.
4934  */
4935 int ata_qc_complete_multiple(struct ata_port *ap, u32 qc_active)
4936 {
4937 	int nr_done = 0;
4938 	u32 done_mask;
4939 
4940 	done_mask = ap->qc_active ^ qc_active;
4941 
4942 	if (unlikely(done_mask & qc_active)) {
4943 		ata_port_printk(ap, KERN_ERR, "illegal qc_active transition "
4944 				"(%08x->%08x)\n", ap->qc_active, qc_active);
4945 		return -EINVAL;
4946 	}
4947 
4948 	while (done_mask) {
4949 		struct ata_queued_cmd *qc;
4950 		unsigned int tag = __ffs(done_mask);
4951 
4952 		qc = ata_qc_from_tag(ap, tag);
4953 		if (qc) {
4954 			ata_qc_complete(qc);
4955 			nr_done++;
4956 		}
4957 		done_mask &= ~(1 << tag);
4958 	}
4959 
4960 	return nr_done;
4961 }
4962 
4963 /**
4964  *	ata_qc_issue - issue taskfile to device
4965  *	@qc: command to issue to device
4966  *
4967  *	Prepare an ATA command to submission to device.
4968  *	This includes mapping the data into a DMA-able
4969  *	area, filling in the S/G table, and finally
4970  *	writing the taskfile to hardware, starting the command.
4971  *
4972  *	LOCKING:
4973  *	spin_lock_irqsave(host lock)
4974  */
4975 void ata_qc_issue(struct ata_queued_cmd *qc)
4976 {
4977 	struct ata_port *ap = qc->ap;
4978 	struct ata_link *link = qc->dev->link;
4979 	u8 prot = qc->tf.protocol;
4980 
4981 	/* Make sure only one non-NCQ command is outstanding.  The
4982 	 * check is skipped for old EH because it reuses active qc to
4983 	 * request ATAPI sense.
4984 	 */
4985 	WARN_ON_ONCE(ap->ops->error_handler && ata_tag_valid(link->active_tag));
4986 
4987 	if (ata_is_ncq(prot)) {
4988 		WARN_ON_ONCE(link->sactive & (1 << qc->tag));
4989 
4990 		if (!link->sactive)
4991 			ap->nr_active_links++;
4992 		link->sactive |= 1 << qc->tag;
4993 	} else {
4994 		WARN_ON_ONCE(link->sactive);
4995 
4996 		ap->nr_active_links++;
4997 		link->active_tag = qc->tag;
4998 	}
4999 
5000 	qc->flags |= ATA_QCFLAG_ACTIVE;
5001 	ap->qc_active |= 1 << qc->tag;
5002 
5003 	/*
5004 	 * We guarantee to LLDs that they will have at least one
5005 	 * non-zero sg if the command is a data command.
5006 	 */
5007 	if (WARN_ON_ONCE(ata_is_data(prot) &&
5008 			 (!qc->sg || !qc->n_elem || !qc->nbytes)))
5009 		goto sys_err;
5010 
5011 	if (ata_is_dma(prot) || (ata_is_pio(prot) &&
5012 				 (ap->flags & ATA_FLAG_PIO_DMA)))
5013 		if (ata_sg_setup(qc))
5014 			goto sys_err;
5015 
5016 	/* if device is sleeping, schedule reset and abort the link */
5017 	if (unlikely(qc->dev->flags & ATA_DFLAG_SLEEPING)) {
5018 		link->eh_info.action |= ATA_EH_RESET;
5019 		ata_ehi_push_desc(&link->eh_info, "waking up from sleep");
5020 		ata_link_abort(link);
5021 		return;
5022 	}
5023 
5024 	ap->ops->qc_prep(qc);
5025 
5026 	qc->err_mask |= ap->ops->qc_issue(qc);
5027 	if (unlikely(qc->err_mask))
5028 		goto err;
5029 	return;
5030 
5031 sys_err:
5032 	qc->err_mask |= AC_ERR_SYSTEM;
5033 err:
5034 	ata_qc_complete(qc);
5035 }
5036 
5037 /**
5038  *	sata_scr_valid - test whether SCRs are accessible
5039  *	@link: ATA link to test SCR accessibility for
5040  *
5041  *	Test whether SCRs are accessible for @link.
5042  *
5043  *	LOCKING:
5044  *	None.
5045  *
5046  *	RETURNS:
5047  *	1 if SCRs are accessible, 0 otherwise.
5048  */
5049 int sata_scr_valid(struct ata_link *link)
5050 {
5051 	struct ata_port *ap = link->ap;
5052 
5053 	return (ap->flags & ATA_FLAG_SATA) && ap->ops->scr_read;
5054 }
5055 
5056 /**
5057  *	sata_scr_read - read SCR register of the specified port
5058  *	@link: ATA link to read SCR for
5059  *	@reg: SCR to read
5060  *	@val: Place to store read value
5061  *
5062  *	Read SCR register @reg of @link into *@val.  This function is
5063  *	guaranteed to succeed if @link is ap->link, the cable type of
5064  *	the port is SATA and the port implements ->scr_read.
5065  *
5066  *	LOCKING:
5067  *	None if @link is ap->link.  Kernel thread context otherwise.
5068  *
5069  *	RETURNS:
5070  *	0 on success, negative errno on failure.
5071  */
5072 int sata_scr_read(struct ata_link *link, int reg, u32 *val)
5073 {
5074 	if (ata_is_host_link(link)) {
5075 		if (sata_scr_valid(link))
5076 			return link->ap->ops->scr_read(link, reg, val);
5077 		return -EOPNOTSUPP;
5078 	}
5079 
5080 	return sata_pmp_scr_read(link, reg, val);
5081 }
5082 
5083 /**
5084  *	sata_scr_write - write SCR register of the specified port
5085  *	@link: ATA link to write SCR for
5086  *	@reg: SCR to write
5087  *	@val: value to write
5088  *
5089  *	Write @val to SCR register @reg of @link.  This function is
5090  *	guaranteed to succeed if @link is ap->link, the cable type of
5091  *	the port is SATA and the port implements ->scr_read.
5092  *
5093  *	LOCKING:
5094  *	None if @link is ap->link.  Kernel thread context otherwise.
5095  *
5096  *	RETURNS:
5097  *	0 on success, negative errno on failure.
5098  */
5099 int sata_scr_write(struct ata_link *link, int reg, u32 val)
5100 {
5101 	if (ata_is_host_link(link)) {
5102 		if (sata_scr_valid(link))
5103 			return link->ap->ops->scr_write(link, reg, val);
5104 		return -EOPNOTSUPP;
5105 	}
5106 
5107 	return sata_pmp_scr_write(link, reg, val);
5108 }
5109 
5110 /**
5111  *	sata_scr_write_flush - write SCR register of the specified port and flush
5112  *	@link: ATA link to write SCR for
5113  *	@reg: SCR to write
5114  *	@val: value to write
5115  *
5116  *	This function is identical to sata_scr_write() except that this
5117  *	function performs flush after writing to the register.
5118  *
5119  *	LOCKING:
5120  *	None if @link is ap->link.  Kernel thread context otherwise.
5121  *
5122  *	RETURNS:
5123  *	0 on success, negative errno on failure.
5124  */
5125 int sata_scr_write_flush(struct ata_link *link, int reg, u32 val)
5126 {
5127 	if (ata_is_host_link(link)) {
5128 		int rc;
5129 
5130 		if (sata_scr_valid(link)) {
5131 			rc = link->ap->ops->scr_write(link, reg, val);
5132 			if (rc == 0)
5133 				rc = link->ap->ops->scr_read(link, reg, &val);
5134 			return rc;
5135 		}
5136 		return -EOPNOTSUPP;
5137 	}
5138 
5139 	return sata_pmp_scr_write(link, reg, val);
5140 }
5141 
5142 /**
5143  *	ata_phys_link_online - test whether the given link is online
5144  *	@link: ATA link to test
5145  *
5146  *	Test whether @link is online.  Note that this function returns
5147  *	0 if online status of @link cannot be obtained, so
5148  *	ata_link_online(link) != !ata_link_offline(link).
5149  *
5150  *	LOCKING:
5151  *	None.
5152  *
5153  *	RETURNS:
5154  *	True if the port online status is available and online.
5155  */
5156 bool ata_phys_link_online(struct ata_link *link)
5157 {
5158 	u32 sstatus;
5159 
5160 	if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0 &&
5161 	    ata_sstatus_online(sstatus))
5162 		return true;
5163 	return false;
5164 }
5165 
5166 /**
5167  *	ata_phys_link_offline - test whether the given link is offline
5168  *	@link: ATA link to test
5169  *
5170  *	Test whether @link is offline.  Note that this function
5171  *	returns 0 if offline status of @link cannot be obtained, so
5172  *	ata_link_online(link) != !ata_link_offline(link).
5173  *
5174  *	LOCKING:
5175  *	None.
5176  *
5177  *	RETURNS:
5178  *	True if the port offline status is available and offline.
5179  */
5180 bool ata_phys_link_offline(struct ata_link *link)
5181 {
5182 	u32 sstatus;
5183 
5184 	if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0 &&
5185 	    !ata_sstatus_online(sstatus))
5186 		return true;
5187 	return false;
5188 }
5189 
5190 /**
5191  *	ata_link_online - test whether the given link is online
5192  *	@link: ATA link to test
5193  *
5194  *	Test whether @link is online.  This is identical to
5195  *	ata_phys_link_online() when there's no slave link.  When
5196  *	there's a slave link, this function should only be called on
5197  *	the master link and will return true if any of M/S links is
5198  *	online.
5199  *
5200  *	LOCKING:
5201  *	None.
5202  *
5203  *	RETURNS:
5204  *	True if the port online status is available and online.
5205  */
5206 bool ata_link_online(struct ata_link *link)
5207 {
5208 	struct ata_link *slave = link->ap->slave_link;
5209 
5210 	WARN_ON(link == slave);	/* shouldn't be called on slave link */
5211 
5212 	return ata_phys_link_online(link) ||
5213 		(slave && ata_phys_link_online(slave));
5214 }
5215 
5216 /**
5217  *	ata_link_offline - test whether the given link is offline
5218  *	@link: ATA link to test
5219  *
5220  *	Test whether @link is offline.  This is identical to
5221  *	ata_phys_link_offline() when there's no slave link.  When
5222  *	there's a slave link, this function should only be called on
5223  *	the master link and will return true if both M/S links are
5224  *	offline.
5225  *
5226  *	LOCKING:
5227  *	None.
5228  *
5229  *	RETURNS:
5230  *	True if the port offline status is available and offline.
5231  */
5232 bool ata_link_offline(struct ata_link *link)
5233 {
5234 	struct ata_link *slave = link->ap->slave_link;
5235 
5236 	WARN_ON(link == slave);	/* shouldn't be called on slave link */
5237 
5238 	return ata_phys_link_offline(link) &&
5239 		(!slave || ata_phys_link_offline(slave));
5240 }
5241 
5242 #ifdef CONFIG_PM
5243 static int ata_host_request_pm(struct ata_host *host, pm_message_t mesg,
5244 			       unsigned int action, unsigned int ehi_flags,
5245 			       int wait)
5246 {
5247 	unsigned long flags;
5248 	int i, rc;
5249 
5250 	for (i = 0; i < host->n_ports; i++) {
5251 		struct ata_port *ap = host->ports[i];
5252 		struct ata_link *link;
5253 
5254 		/* Previous resume operation might still be in
5255 		 * progress.  Wait for PM_PENDING to clear.
5256 		 */
5257 		if (ap->pflags & ATA_PFLAG_PM_PENDING) {
5258 			ata_port_wait_eh(ap);
5259 			WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
5260 		}
5261 
5262 		/* request PM ops to EH */
5263 		spin_lock_irqsave(ap->lock, flags);
5264 
5265 		ap->pm_mesg = mesg;
5266 		if (wait) {
5267 			rc = 0;
5268 			ap->pm_result = &rc;
5269 		}
5270 
5271 		ap->pflags |= ATA_PFLAG_PM_PENDING;
5272 		ata_for_each_link(link, ap, HOST_FIRST) {
5273 			link->eh_info.action |= action;
5274 			link->eh_info.flags |= ehi_flags;
5275 		}
5276 
5277 		ata_port_schedule_eh(ap);
5278 
5279 		spin_unlock_irqrestore(ap->lock, flags);
5280 
5281 		/* wait and check result */
5282 		if (wait) {
5283 			ata_port_wait_eh(ap);
5284 			WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
5285 			if (rc)
5286 				return rc;
5287 		}
5288 	}
5289 
5290 	return 0;
5291 }
5292 
5293 /**
5294  *	ata_host_suspend - suspend host
5295  *	@host: host to suspend
5296  *	@mesg: PM message
5297  *
5298  *	Suspend @host.  Actual operation is performed by EH.  This
5299  *	function requests EH to perform PM operations and waits for EH
5300  *	to finish.
5301  *
5302  *	LOCKING:
5303  *	Kernel thread context (may sleep).
5304  *
5305  *	RETURNS:
5306  *	0 on success, -errno on failure.
5307  */
5308 int ata_host_suspend(struct ata_host *host, pm_message_t mesg)
5309 {
5310 	unsigned int ehi_flags = ATA_EHI_QUIET;
5311 	int rc;
5312 
5313 	/*
5314 	 * On some hardware, device fails to respond after spun down
5315 	 * for suspend.  As the device won't be used before being
5316 	 * resumed, we don't need to touch the device.  Ask EH to skip
5317 	 * the usual stuff and proceed directly to suspend.
5318 	 *
5319 	 * http://thread.gmane.org/gmane.linux.ide/46764
5320 	 */
5321 	if (mesg.event == PM_EVENT_SUSPEND)
5322 		ehi_flags |= ATA_EHI_NO_AUTOPSY | ATA_EHI_NO_RECOVERY;
5323 
5324 	rc = ata_host_request_pm(host, mesg, 0, ehi_flags, 1);
5325 	if (rc == 0)
5326 		host->dev->power.power_state = mesg;
5327 	return rc;
5328 }
5329 
5330 /**
5331  *	ata_host_resume - resume host
5332  *	@host: host to resume
5333  *
5334  *	Resume @host.  Actual operation is performed by EH.  This
5335  *	function requests EH to perform PM operations and returns.
5336  *	Note that all resume operations are performed parallely.
5337  *
5338  *	LOCKING:
5339  *	Kernel thread context (may sleep).
5340  */
5341 void ata_host_resume(struct ata_host *host)
5342 {
5343 	ata_host_request_pm(host, PMSG_ON, ATA_EH_RESET,
5344 			    ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET, 0);
5345 	host->dev->power.power_state = PMSG_ON;
5346 }
5347 #endif
5348 
5349 /**
5350  *	ata_dev_init - Initialize an ata_device structure
5351  *	@dev: Device structure to initialize
5352  *
5353  *	Initialize @dev in preparation for probing.
5354  *
5355  *	LOCKING:
5356  *	Inherited from caller.
5357  */
5358 void ata_dev_init(struct ata_device *dev)
5359 {
5360 	struct ata_link *link = ata_dev_phys_link(dev);
5361 	struct ata_port *ap = link->ap;
5362 	unsigned long flags;
5363 
5364 	/* SATA spd limit is bound to the attached device, reset together */
5365 	link->sata_spd_limit = link->hw_sata_spd_limit;
5366 	link->sata_spd = 0;
5367 
5368 	/* High bits of dev->flags are used to record warm plug
5369 	 * requests which occur asynchronously.  Synchronize using
5370 	 * host lock.
5371 	 */
5372 	spin_lock_irqsave(ap->lock, flags);
5373 	dev->flags &= ~ATA_DFLAG_INIT_MASK;
5374 	dev->horkage = 0;
5375 	spin_unlock_irqrestore(ap->lock, flags);
5376 
5377 	memset((void *)dev + ATA_DEVICE_CLEAR_BEGIN, 0,
5378 	       ATA_DEVICE_CLEAR_END - ATA_DEVICE_CLEAR_BEGIN);
5379 	dev->pio_mask = UINT_MAX;
5380 	dev->mwdma_mask = UINT_MAX;
5381 	dev->udma_mask = UINT_MAX;
5382 }
5383 
5384 /**
5385  *	ata_link_init - Initialize an ata_link structure
5386  *	@ap: ATA port link is attached to
5387  *	@link: Link structure to initialize
5388  *	@pmp: Port multiplier port number
5389  *
5390  *	Initialize @link.
5391  *
5392  *	LOCKING:
5393  *	Kernel thread context (may sleep)
5394  */
5395 void ata_link_init(struct ata_port *ap, struct ata_link *link, int pmp)
5396 {
5397 	int i;
5398 
5399 	/* clear everything except for devices */
5400 	memset((void *)link + ATA_LINK_CLEAR_BEGIN, 0,
5401 	       ATA_LINK_CLEAR_END - ATA_LINK_CLEAR_BEGIN);
5402 
5403 	link->ap = ap;
5404 	link->pmp = pmp;
5405 	link->active_tag = ATA_TAG_POISON;
5406 	link->hw_sata_spd_limit = UINT_MAX;
5407 
5408 	/* can't use iterator, ap isn't initialized yet */
5409 	for (i = 0; i < ATA_MAX_DEVICES; i++) {
5410 		struct ata_device *dev = &link->device[i];
5411 
5412 		dev->link = link;
5413 		dev->devno = dev - link->device;
5414 #ifdef CONFIG_ATA_ACPI
5415 		dev->gtf_filter = ata_acpi_gtf_filter;
5416 #endif
5417 		ata_dev_init(dev);
5418 	}
5419 }
5420 
5421 /**
5422  *	sata_link_init_spd - Initialize link->sata_spd_limit
5423  *	@link: Link to configure sata_spd_limit for
5424  *
5425  *	Initialize @link->[hw_]sata_spd_limit to the currently
5426  *	configured value.
5427  *
5428  *	LOCKING:
5429  *	Kernel thread context (may sleep).
5430  *
5431  *	RETURNS:
5432  *	0 on success, -errno on failure.
5433  */
5434 int sata_link_init_spd(struct ata_link *link)
5435 {
5436 	u8 spd;
5437 	int rc;
5438 
5439 	rc = sata_scr_read(link, SCR_CONTROL, &link->saved_scontrol);
5440 	if (rc)
5441 		return rc;
5442 
5443 	spd = (link->saved_scontrol >> 4) & 0xf;
5444 	if (spd)
5445 		link->hw_sata_spd_limit &= (1 << spd) - 1;
5446 
5447 	ata_force_link_limits(link);
5448 
5449 	link->sata_spd_limit = link->hw_sata_spd_limit;
5450 
5451 	return 0;
5452 }
5453 
5454 /**
5455  *	ata_port_alloc - allocate and initialize basic ATA port resources
5456  *	@host: ATA host this allocated port belongs to
5457  *
5458  *	Allocate and initialize basic ATA port resources.
5459  *
5460  *	RETURNS:
5461  *	Allocate ATA port on success, NULL on failure.
5462  *
5463  *	LOCKING:
5464  *	Inherited from calling layer (may sleep).
5465  */
5466 struct ata_port *ata_port_alloc(struct ata_host *host)
5467 {
5468 	struct ata_port *ap;
5469 
5470 	DPRINTK("ENTER\n");
5471 
5472 	ap = kzalloc(sizeof(*ap), GFP_KERNEL);
5473 	if (!ap)
5474 		return NULL;
5475 
5476 	ap->pflags |= ATA_PFLAG_INITIALIZING;
5477 	ap->lock = &host->lock;
5478 	ap->print_id = -1;
5479 	ap->host = host;
5480 	ap->dev = host->dev;
5481 
5482 #if defined(ATA_VERBOSE_DEBUG)
5483 	/* turn on all debugging levels */
5484 	ap->msg_enable = 0x00FF;
5485 #elif defined(ATA_DEBUG)
5486 	ap->msg_enable = ATA_MSG_DRV | ATA_MSG_INFO | ATA_MSG_CTL | ATA_MSG_WARN | ATA_MSG_ERR;
5487 #else
5488 	ap->msg_enable = ATA_MSG_DRV | ATA_MSG_ERR | ATA_MSG_WARN;
5489 #endif
5490 
5491 	mutex_init(&ap->scsi_scan_mutex);
5492 	INIT_DELAYED_WORK(&ap->hotplug_task, ata_scsi_hotplug);
5493 	INIT_WORK(&ap->scsi_rescan_task, ata_scsi_dev_rescan);
5494 	INIT_LIST_HEAD(&ap->eh_done_q);
5495 	init_waitqueue_head(&ap->eh_wait_q);
5496 	init_completion(&ap->park_req_pending);
5497 	init_timer_deferrable(&ap->fastdrain_timer);
5498 	ap->fastdrain_timer.function = ata_eh_fastdrain_timerfn;
5499 	ap->fastdrain_timer.data = (unsigned long)ap;
5500 
5501 	ap->cbl = ATA_CBL_NONE;
5502 
5503 	ata_link_init(ap, &ap->link, 0);
5504 
5505 #ifdef ATA_IRQ_TRAP
5506 	ap->stats.unhandled_irq = 1;
5507 	ap->stats.idle_irq = 1;
5508 #endif
5509 	ata_sff_port_init(ap);
5510 
5511 	return ap;
5512 }
5513 
5514 static void ata_host_release(struct device *gendev, void *res)
5515 {
5516 	struct ata_host *host = dev_get_drvdata(gendev);
5517 	int i;
5518 
5519 	for (i = 0; i < host->n_ports; i++) {
5520 		struct ata_port *ap = host->ports[i];
5521 
5522 		if (!ap)
5523 			continue;
5524 
5525 		if (ap->scsi_host)
5526 			scsi_host_put(ap->scsi_host);
5527 
5528 		kfree(ap->pmp_link);
5529 		kfree(ap->slave_link);
5530 		kfree(ap);
5531 		host->ports[i] = NULL;
5532 	}
5533 
5534 	dev_set_drvdata(gendev, NULL);
5535 }
5536 
5537 /**
5538  *	ata_host_alloc - allocate and init basic ATA host resources
5539  *	@dev: generic device this host is associated with
5540  *	@max_ports: maximum number of ATA ports associated with this host
5541  *
5542  *	Allocate and initialize basic ATA host resources.  LLD calls
5543  *	this function to allocate a host, initializes it fully and
5544  *	attaches it using ata_host_register().
5545  *
5546  *	@max_ports ports are allocated and host->n_ports is
5547  *	initialized to @max_ports.  The caller is allowed to decrease
5548  *	host->n_ports before calling ata_host_register().  The unused
5549  *	ports will be automatically freed on registration.
5550  *
5551  *	RETURNS:
5552  *	Allocate ATA host on success, NULL on failure.
5553  *
5554  *	LOCKING:
5555  *	Inherited from calling layer (may sleep).
5556  */
5557 struct ata_host *ata_host_alloc(struct device *dev, int max_ports)
5558 {
5559 	struct ata_host *host;
5560 	size_t sz;
5561 	int i;
5562 
5563 	DPRINTK("ENTER\n");
5564 
5565 	if (!devres_open_group(dev, NULL, GFP_KERNEL))
5566 		return NULL;
5567 
5568 	/* alloc a container for our list of ATA ports (buses) */
5569 	sz = sizeof(struct ata_host) + (max_ports + 1) * sizeof(void *);
5570 	/* alloc a container for our list of ATA ports (buses) */
5571 	host = devres_alloc(ata_host_release, sz, GFP_KERNEL);
5572 	if (!host)
5573 		goto err_out;
5574 
5575 	devres_add(dev, host);
5576 	dev_set_drvdata(dev, host);
5577 
5578 	spin_lock_init(&host->lock);
5579 	mutex_init(&host->eh_mutex);
5580 	host->dev = dev;
5581 	host->n_ports = max_ports;
5582 
5583 	/* allocate ports bound to this host */
5584 	for (i = 0; i < max_ports; i++) {
5585 		struct ata_port *ap;
5586 
5587 		ap = ata_port_alloc(host);
5588 		if (!ap)
5589 			goto err_out;
5590 
5591 		ap->port_no = i;
5592 		host->ports[i] = ap;
5593 	}
5594 
5595 	devres_remove_group(dev, NULL);
5596 	return host;
5597 
5598  err_out:
5599 	devres_release_group(dev, NULL);
5600 	return NULL;
5601 }
5602 
5603 /**
5604  *	ata_host_alloc_pinfo - alloc host and init with port_info array
5605  *	@dev: generic device this host is associated with
5606  *	@ppi: array of ATA port_info to initialize host with
5607  *	@n_ports: number of ATA ports attached to this host
5608  *
5609  *	Allocate ATA host and initialize with info from @ppi.  If NULL
5610  *	terminated, @ppi may contain fewer entries than @n_ports.  The
5611  *	last entry will be used for the remaining ports.
5612  *
5613  *	RETURNS:
5614  *	Allocate ATA host on success, NULL on failure.
5615  *
5616  *	LOCKING:
5617  *	Inherited from calling layer (may sleep).
5618  */
5619 struct ata_host *ata_host_alloc_pinfo(struct device *dev,
5620 				      const struct ata_port_info * const * ppi,
5621 				      int n_ports)
5622 {
5623 	const struct ata_port_info *pi;
5624 	struct ata_host *host;
5625 	int i, j;
5626 
5627 	host = ata_host_alloc(dev, n_ports);
5628 	if (!host)
5629 		return NULL;
5630 
5631 	for (i = 0, j = 0, pi = NULL; i < host->n_ports; i++) {
5632 		struct ata_port *ap = host->ports[i];
5633 
5634 		if (ppi[j])
5635 			pi = ppi[j++];
5636 
5637 		ap->pio_mask = pi->pio_mask;
5638 		ap->mwdma_mask = pi->mwdma_mask;
5639 		ap->udma_mask = pi->udma_mask;
5640 		ap->flags |= pi->flags;
5641 		ap->link.flags |= pi->link_flags;
5642 		ap->ops = pi->port_ops;
5643 
5644 		if (!host->ops && (pi->port_ops != &ata_dummy_port_ops))
5645 			host->ops = pi->port_ops;
5646 	}
5647 
5648 	return host;
5649 }
5650 
5651 /**
5652  *	ata_slave_link_init - initialize slave link
5653  *	@ap: port to initialize slave link for
5654  *
5655  *	Create and initialize slave link for @ap.  This enables slave
5656  *	link handling on the port.
5657  *
5658  *	In libata, a port contains links and a link contains devices.
5659  *	There is single host link but if a PMP is attached to it,
5660  *	there can be multiple fan-out links.  On SATA, there's usually
5661  *	a single device connected to a link but PATA and SATA
5662  *	controllers emulating TF based interface can have two - master
5663  *	and slave.
5664  *
5665  *	However, there are a few controllers which don't fit into this
5666  *	abstraction too well - SATA controllers which emulate TF
5667  *	interface with both master and slave devices but also have
5668  *	separate SCR register sets for each device.  These controllers
5669  *	need separate links for physical link handling
5670  *	(e.g. onlineness, link speed) but should be treated like a
5671  *	traditional M/S controller for everything else (e.g. command
5672  *	issue, softreset).
5673  *
5674  *	slave_link is libata's way of handling this class of
5675  *	controllers without impacting core layer too much.  For
5676  *	anything other than physical link handling, the default host
5677  *	link is used for both master and slave.  For physical link
5678  *	handling, separate @ap->slave_link is used.  All dirty details
5679  *	are implemented inside libata core layer.  From LLD's POV, the
5680  *	only difference is that prereset, hardreset and postreset are
5681  *	called once more for the slave link, so the reset sequence
5682  *	looks like the following.
5683  *
5684  *	prereset(M) -> prereset(S) -> hardreset(M) -> hardreset(S) ->
5685  *	softreset(M) -> postreset(M) -> postreset(S)
5686  *
5687  *	Note that softreset is called only for the master.  Softreset
5688  *	resets both M/S by definition, so SRST on master should handle
5689  *	both (the standard method will work just fine).
5690  *
5691  *	LOCKING:
5692  *	Should be called before host is registered.
5693  *
5694  *	RETURNS:
5695  *	0 on success, -errno on failure.
5696  */
5697 int ata_slave_link_init(struct ata_port *ap)
5698 {
5699 	struct ata_link *link;
5700 
5701 	WARN_ON(ap->slave_link);
5702 	WARN_ON(ap->flags & ATA_FLAG_PMP);
5703 
5704 	link = kzalloc(sizeof(*link), GFP_KERNEL);
5705 	if (!link)
5706 		return -ENOMEM;
5707 
5708 	ata_link_init(ap, link, 1);
5709 	ap->slave_link = link;
5710 	return 0;
5711 }
5712 
5713 static void ata_host_stop(struct device *gendev, void *res)
5714 {
5715 	struct ata_host *host = dev_get_drvdata(gendev);
5716 	int i;
5717 
5718 	WARN_ON(!(host->flags & ATA_HOST_STARTED));
5719 
5720 	for (i = 0; i < host->n_ports; i++) {
5721 		struct ata_port *ap = host->ports[i];
5722 
5723 		if (ap->ops->port_stop)
5724 			ap->ops->port_stop(ap);
5725 	}
5726 
5727 	if (host->ops->host_stop)
5728 		host->ops->host_stop(host);
5729 }
5730 
5731 /**
5732  *	ata_finalize_port_ops - finalize ata_port_operations
5733  *	@ops: ata_port_operations to finalize
5734  *
5735  *	An ata_port_operations can inherit from another ops and that
5736  *	ops can again inherit from another.  This can go on as many
5737  *	times as necessary as long as there is no loop in the
5738  *	inheritance chain.
5739  *
5740  *	Ops tables are finalized when the host is started.  NULL or
5741  *	unspecified entries are inherited from the closet ancestor
5742  *	which has the method and the entry is populated with it.
5743  *	After finalization, the ops table directly points to all the
5744  *	methods and ->inherits is no longer necessary and cleared.
5745  *
5746  *	Using ATA_OP_NULL, inheriting ops can force a method to NULL.
5747  *
5748  *	LOCKING:
5749  *	None.
5750  */
5751 static void ata_finalize_port_ops(struct ata_port_operations *ops)
5752 {
5753 	static DEFINE_SPINLOCK(lock);
5754 	const struct ata_port_operations *cur;
5755 	void **begin = (void **)ops;
5756 	void **end = (void **)&ops->inherits;
5757 	void **pp;
5758 
5759 	if (!ops || !ops->inherits)
5760 		return;
5761 
5762 	spin_lock(&lock);
5763 
5764 	for (cur = ops->inherits; cur; cur = cur->inherits) {
5765 		void **inherit = (void **)cur;
5766 
5767 		for (pp = begin; pp < end; pp++, inherit++)
5768 			if (!*pp)
5769 				*pp = *inherit;
5770 	}
5771 
5772 	for (pp = begin; pp < end; pp++)
5773 		if (IS_ERR(*pp))
5774 			*pp = NULL;
5775 
5776 	ops->inherits = NULL;
5777 
5778 	spin_unlock(&lock);
5779 }
5780 
5781 /**
5782  *	ata_host_start - start and freeze ports of an ATA host
5783  *	@host: ATA host to start ports for
5784  *
5785  *	Start and then freeze ports of @host.  Started status is
5786  *	recorded in host->flags, so this function can be called
5787  *	multiple times.  Ports are guaranteed to get started only
5788  *	once.  If host->ops isn't initialized yet, its set to the
5789  *	first non-dummy port ops.
5790  *
5791  *	LOCKING:
5792  *	Inherited from calling layer (may sleep).
5793  *
5794  *	RETURNS:
5795  *	0 if all ports are started successfully, -errno otherwise.
5796  */
5797 int ata_host_start(struct ata_host *host)
5798 {
5799 	int have_stop = 0;
5800 	void *start_dr = NULL;
5801 	int i, rc;
5802 
5803 	if (host->flags & ATA_HOST_STARTED)
5804 		return 0;
5805 
5806 	ata_finalize_port_ops(host->ops);
5807 
5808 	for (i = 0; i < host->n_ports; i++) {
5809 		struct ata_port *ap = host->ports[i];
5810 
5811 		ata_finalize_port_ops(ap->ops);
5812 
5813 		if (!host->ops && !ata_port_is_dummy(ap))
5814 			host->ops = ap->ops;
5815 
5816 		if (ap->ops->port_stop)
5817 			have_stop = 1;
5818 	}
5819 
5820 	if (host->ops->host_stop)
5821 		have_stop = 1;
5822 
5823 	if (have_stop) {
5824 		start_dr = devres_alloc(ata_host_stop, 0, GFP_KERNEL);
5825 		if (!start_dr)
5826 			return -ENOMEM;
5827 	}
5828 
5829 	for (i = 0; i < host->n_ports; i++) {
5830 		struct ata_port *ap = host->ports[i];
5831 
5832 		if (ap->ops->port_start) {
5833 			rc = ap->ops->port_start(ap);
5834 			if (rc) {
5835 				if (rc != -ENODEV)
5836 					dev_printk(KERN_ERR, host->dev,
5837 						"failed to start port %d "
5838 						"(errno=%d)\n", i, rc);
5839 				goto err_out;
5840 			}
5841 		}
5842 		ata_eh_freeze_port(ap);
5843 	}
5844 
5845 	if (start_dr)
5846 		devres_add(host->dev, start_dr);
5847 	host->flags |= ATA_HOST_STARTED;
5848 	return 0;
5849 
5850  err_out:
5851 	while (--i >= 0) {
5852 		struct ata_port *ap = host->ports[i];
5853 
5854 		if (ap->ops->port_stop)
5855 			ap->ops->port_stop(ap);
5856 	}
5857 	devres_free(start_dr);
5858 	return rc;
5859 }
5860 
5861 /**
5862  *	ata_sas_host_init - Initialize a host struct
5863  *	@host:	host to initialize
5864  *	@dev:	device host is attached to
5865  *	@flags:	host flags
5866  *	@ops:	port_ops
5867  *
5868  *	LOCKING:
5869  *	PCI/etc. bus probe sem.
5870  *
5871  */
5872 /* KILLME - the only user left is ipr */
5873 void ata_host_init(struct ata_host *host, struct device *dev,
5874 		   unsigned long flags, struct ata_port_operations *ops)
5875 {
5876 	spin_lock_init(&host->lock);
5877 	mutex_init(&host->eh_mutex);
5878 	host->dev = dev;
5879 	host->flags = flags;
5880 	host->ops = ops;
5881 }
5882 
5883 
5884 static void async_port_probe(void *data, async_cookie_t cookie)
5885 {
5886 	int rc;
5887 	struct ata_port *ap = data;
5888 
5889 	/*
5890 	 * If we're not allowed to scan this host in parallel,
5891 	 * we need to wait until all previous scans have completed
5892 	 * before going further.
5893 	 * Jeff Garzik says this is only within a controller, so we
5894 	 * don't need to wait for port 0, only for later ports.
5895 	 */
5896 	if (!(ap->host->flags & ATA_HOST_PARALLEL_SCAN) && ap->port_no != 0)
5897 		async_synchronize_cookie(cookie);
5898 
5899 	/* probe */
5900 	if (ap->ops->error_handler) {
5901 		struct ata_eh_info *ehi = &ap->link.eh_info;
5902 		unsigned long flags;
5903 
5904 		/* kick EH for boot probing */
5905 		spin_lock_irqsave(ap->lock, flags);
5906 
5907 		ehi->probe_mask |= ATA_ALL_DEVICES;
5908 		ehi->action |= ATA_EH_RESET;
5909 		ehi->flags |= ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET;
5910 
5911 		ap->pflags &= ~ATA_PFLAG_INITIALIZING;
5912 		ap->pflags |= ATA_PFLAG_LOADING;
5913 		ata_port_schedule_eh(ap);
5914 
5915 		spin_unlock_irqrestore(ap->lock, flags);
5916 
5917 		/* wait for EH to finish */
5918 		ata_port_wait_eh(ap);
5919 	} else {
5920 		DPRINTK("ata%u: bus probe begin\n", ap->print_id);
5921 		rc = ata_bus_probe(ap);
5922 		DPRINTK("ata%u: bus probe end\n", ap->print_id);
5923 
5924 		if (rc) {
5925 			/* FIXME: do something useful here?
5926 			 * Current libata behavior will
5927 			 * tear down everything when
5928 			 * the module is removed
5929 			 * or the h/w is unplugged.
5930 			 */
5931 		}
5932 	}
5933 
5934 	/* in order to keep device order, we need to synchronize at this point */
5935 	async_synchronize_cookie(cookie);
5936 
5937 	ata_scsi_scan_host(ap, 1);
5938 
5939 }
5940 /**
5941  *	ata_host_register - register initialized ATA host
5942  *	@host: ATA host to register
5943  *	@sht: template for SCSI host
5944  *
5945  *	Register initialized ATA host.  @host is allocated using
5946  *	ata_host_alloc() and fully initialized by LLD.  This function
5947  *	starts ports, registers @host with ATA and SCSI layers and
5948  *	probe registered devices.
5949  *
5950  *	LOCKING:
5951  *	Inherited from calling layer (may sleep).
5952  *
5953  *	RETURNS:
5954  *	0 on success, -errno otherwise.
5955  */
5956 int ata_host_register(struct ata_host *host, struct scsi_host_template *sht)
5957 {
5958 	int i, rc;
5959 
5960 	/* host must have been started */
5961 	if (!(host->flags & ATA_HOST_STARTED)) {
5962 		dev_printk(KERN_ERR, host->dev,
5963 			   "BUG: trying to register unstarted host\n");
5964 		WARN_ON(1);
5965 		return -EINVAL;
5966 	}
5967 
5968 	/* Blow away unused ports.  This happens when LLD can't
5969 	 * determine the exact number of ports to allocate at
5970 	 * allocation time.
5971 	 */
5972 	for (i = host->n_ports; host->ports[i]; i++)
5973 		kfree(host->ports[i]);
5974 
5975 	/* give ports names and add SCSI hosts */
5976 	for (i = 0; i < host->n_ports; i++)
5977 		host->ports[i]->print_id = ata_print_id++;
5978 
5979 
5980 	/* Create associated sysfs transport objects  */
5981 	for (i = 0; i < host->n_ports; i++) {
5982 		rc = ata_tport_add(host->dev,host->ports[i]);
5983 		if (rc) {
5984 			goto err_tadd;
5985 		}
5986 	}
5987 
5988 	rc = ata_scsi_add_hosts(host, sht);
5989 	if (rc)
5990 		goto err_tadd;
5991 
5992 	/* associate with ACPI nodes */
5993 	ata_acpi_associate(host);
5994 
5995 	/* set cable, sata_spd_limit and report */
5996 	for (i = 0; i < host->n_ports; i++) {
5997 		struct ata_port *ap = host->ports[i];
5998 		unsigned long xfer_mask;
5999 
6000 		/* set SATA cable type if still unset */
6001 		if (ap->cbl == ATA_CBL_NONE && (ap->flags & ATA_FLAG_SATA))
6002 			ap->cbl = ATA_CBL_SATA;
6003 
6004 		/* init sata_spd_limit to the current value */
6005 		sata_link_init_spd(&ap->link);
6006 		if (ap->slave_link)
6007 			sata_link_init_spd(ap->slave_link);
6008 
6009 		/* print per-port info to dmesg */
6010 		xfer_mask = ata_pack_xfermask(ap->pio_mask, ap->mwdma_mask,
6011 					      ap->udma_mask);
6012 
6013 		if (!ata_port_is_dummy(ap)) {
6014 			ata_port_printk(ap, KERN_INFO,
6015 					"%cATA max %s %s\n",
6016 					(ap->flags & ATA_FLAG_SATA) ? 'S' : 'P',
6017 					ata_mode_string(xfer_mask),
6018 					ap->link.eh_info.desc);
6019 			ata_ehi_clear_desc(&ap->link.eh_info);
6020 		} else
6021 			ata_port_printk(ap, KERN_INFO, "DUMMY\n");
6022 	}
6023 
6024 	/* perform each probe asynchronously */
6025 	for (i = 0; i < host->n_ports; i++) {
6026 		struct ata_port *ap = host->ports[i];
6027 		async_schedule(async_port_probe, ap);
6028 	}
6029 
6030 	return 0;
6031 
6032  err_tadd:
6033 	while (--i >= 0) {
6034 		ata_tport_delete(host->ports[i]);
6035 	}
6036 	return rc;
6037 
6038 }
6039 
6040 /**
6041  *	ata_host_activate - start host, request IRQ and register it
6042  *	@host: target ATA host
6043  *	@irq: IRQ to request
6044  *	@irq_handler: irq_handler used when requesting IRQ
6045  *	@irq_flags: irq_flags used when requesting IRQ
6046  *	@sht: scsi_host_template to use when registering the host
6047  *
6048  *	After allocating an ATA host and initializing it, most libata
6049  *	LLDs perform three steps to activate the host - start host,
6050  *	request IRQ and register it.  This helper takes necessasry
6051  *	arguments and performs the three steps in one go.
6052  *
6053  *	An invalid IRQ skips the IRQ registration and expects the host to
6054  *	have set polling mode on the port. In this case, @irq_handler
6055  *	should be NULL.
6056  *
6057  *	LOCKING:
6058  *	Inherited from calling layer (may sleep).
6059  *
6060  *	RETURNS:
6061  *	0 on success, -errno otherwise.
6062  */
6063 int ata_host_activate(struct ata_host *host, int irq,
6064 		      irq_handler_t irq_handler, unsigned long irq_flags,
6065 		      struct scsi_host_template *sht)
6066 {
6067 	int i, rc;
6068 
6069 	rc = ata_host_start(host);
6070 	if (rc)
6071 		return rc;
6072 
6073 	/* Special case for polling mode */
6074 	if (!irq) {
6075 		WARN_ON(irq_handler);
6076 		return ata_host_register(host, sht);
6077 	}
6078 
6079 	rc = devm_request_irq(host->dev, irq, irq_handler, irq_flags,
6080 			      dev_driver_string(host->dev), host);
6081 	if (rc)
6082 		return rc;
6083 
6084 	for (i = 0; i < host->n_ports; i++)
6085 		ata_port_desc(host->ports[i], "irq %d", irq);
6086 
6087 	rc = ata_host_register(host, sht);
6088 	/* if failed, just free the IRQ and leave ports alone */
6089 	if (rc)
6090 		devm_free_irq(host->dev, irq, host);
6091 
6092 	return rc;
6093 }
6094 
6095 /**
6096  *	ata_port_detach - Detach ATA port in prepration of device removal
6097  *	@ap: ATA port to be detached
6098  *
6099  *	Detach all ATA devices and the associated SCSI devices of @ap;
6100  *	then, remove the associated SCSI host.  @ap is guaranteed to
6101  *	be quiescent on return from this function.
6102  *
6103  *	LOCKING:
6104  *	Kernel thread context (may sleep).
6105  */
6106 static void ata_port_detach(struct ata_port *ap)
6107 {
6108 	unsigned long flags;
6109 
6110 	if (!ap->ops->error_handler)
6111 		goto skip_eh;
6112 
6113 	/* tell EH we're leaving & flush EH */
6114 	spin_lock_irqsave(ap->lock, flags);
6115 	ap->pflags |= ATA_PFLAG_UNLOADING;
6116 	ata_port_schedule_eh(ap);
6117 	spin_unlock_irqrestore(ap->lock, flags);
6118 
6119 	/* wait till EH commits suicide */
6120 	ata_port_wait_eh(ap);
6121 
6122 	/* it better be dead now */
6123 	WARN_ON(!(ap->pflags & ATA_PFLAG_UNLOADED));
6124 
6125 	cancel_rearming_delayed_work(&ap->hotplug_task);
6126 
6127  skip_eh:
6128 	if (ap->pmp_link) {
6129 		int i;
6130 		for (i = 0; i < SATA_PMP_MAX_PORTS; i++)
6131 			ata_tlink_delete(&ap->pmp_link[i]);
6132 	}
6133 	ata_tport_delete(ap);
6134 
6135 	/* remove the associated SCSI host */
6136 	scsi_remove_host(ap->scsi_host);
6137 }
6138 
6139 /**
6140  *	ata_host_detach - Detach all ports of an ATA host
6141  *	@host: Host to detach
6142  *
6143  *	Detach all ports of @host.
6144  *
6145  *	LOCKING:
6146  *	Kernel thread context (may sleep).
6147  */
6148 void ata_host_detach(struct ata_host *host)
6149 {
6150 	int i;
6151 
6152 	for (i = 0; i < host->n_ports; i++)
6153 		ata_port_detach(host->ports[i]);
6154 
6155 	/* the host is dead now, dissociate ACPI */
6156 	ata_acpi_dissociate(host);
6157 }
6158 
6159 #ifdef CONFIG_PCI
6160 
6161 /**
6162  *	ata_pci_remove_one - PCI layer callback for device removal
6163  *	@pdev: PCI device that was removed
6164  *
6165  *	PCI layer indicates to libata via this hook that hot-unplug or
6166  *	module unload event has occurred.  Detach all ports.  Resource
6167  *	release is handled via devres.
6168  *
6169  *	LOCKING:
6170  *	Inherited from PCI layer (may sleep).
6171  */
6172 void ata_pci_remove_one(struct pci_dev *pdev)
6173 {
6174 	struct device *dev = &pdev->dev;
6175 	struct ata_host *host = dev_get_drvdata(dev);
6176 
6177 	ata_host_detach(host);
6178 }
6179 
6180 /* move to PCI subsystem */
6181 int pci_test_config_bits(struct pci_dev *pdev, const struct pci_bits *bits)
6182 {
6183 	unsigned long tmp = 0;
6184 
6185 	switch (bits->width) {
6186 	case 1: {
6187 		u8 tmp8 = 0;
6188 		pci_read_config_byte(pdev, bits->reg, &tmp8);
6189 		tmp = tmp8;
6190 		break;
6191 	}
6192 	case 2: {
6193 		u16 tmp16 = 0;
6194 		pci_read_config_word(pdev, bits->reg, &tmp16);
6195 		tmp = tmp16;
6196 		break;
6197 	}
6198 	case 4: {
6199 		u32 tmp32 = 0;
6200 		pci_read_config_dword(pdev, bits->reg, &tmp32);
6201 		tmp = tmp32;
6202 		break;
6203 	}
6204 
6205 	default:
6206 		return -EINVAL;
6207 	}
6208 
6209 	tmp &= bits->mask;
6210 
6211 	return (tmp == bits->val) ? 1 : 0;
6212 }
6213 
6214 #ifdef CONFIG_PM
6215 void ata_pci_device_do_suspend(struct pci_dev *pdev, pm_message_t mesg)
6216 {
6217 	pci_save_state(pdev);
6218 	pci_disable_device(pdev);
6219 
6220 	if (mesg.event & PM_EVENT_SLEEP)
6221 		pci_set_power_state(pdev, PCI_D3hot);
6222 }
6223 
6224 int ata_pci_device_do_resume(struct pci_dev *pdev)
6225 {
6226 	int rc;
6227 
6228 	pci_set_power_state(pdev, PCI_D0);
6229 	pci_restore_state(pdev);
6230 
6231 	rc = pcim_enable_device(pdev);
6232 	if (rc) {
6233 		dev_printk(KERN_ERR, &pdev->dev,
6234 			   "failed to enable device after resume (%d)\n", rc);
6235 		return rc;
6236 	}
6237 
6238 	pci_set_master(pdev);
6239 	return 0;
6240 }
6241 
6242 int ata_pci_device_suspend(struct pci_dev *pdev, pm_message_t mesg)
6243 {
6244 	struct ata_host *host = dev_get_drvdata(&pdev->dev);
6245 	int rc = 0;
6246 
6247 	rc = ata_host_suspend(host, mesg);
6248 	if (rc)
6249 		return rc;
6250 
6251 	ata_pci_device_do_suspend(pdev, mesg);
6252 
6253 	return 0;
6254 }
6255 
6256 int ata_pci_device_resume(struct pci_dev *pdev)
6257 {
6258 	struct ata_host *host = dev_get_drvdata(&pdev->dev);
6259 	int rc;
6260 
6261 	rc = ata_pci_device_do_resume(pdev);
6262 	if (rc == 0)
6263 		ata_host_resume(host);
6264 	return rc;
6265 }
6266 #endif /* CONFIG_PM */
6267 
6268 #endif /* CONFIG_PCI */
6269 
6270 static int __init ata_parse_force_one(char **cur,
6271 				      struct ata_force_ent *force_ent,
6272 				      const char **reason)
6273 {
6274 	/* FIXME: Currently, there's no way to tag init const data and
6275 	 * using __initdata causes build failure on some versions of
6276 	 * gcc.  Once __initdataconst is implemented, add const to the
6277 	 * following structure.
6278 	 */
6279 	static struct ata_force_param force_tbl[] __initdata = {
6280 		{ "40c",	.cbl		= ATA_CBL_PATA40 },
6281 		{ "80c",	.cbl		= ATA_CBL_PATA80 },
6282 		{ "short40c",	.cbl		= ATA_CBL_PATA40_SHORT },
6283 		{ "unk",	.cbl		= ATA_CBL_PATA_UNK },
6284 		{ "ign",	.cbl		= ATA_CBL_PATA_IGN },
6285 		{ "sata",	.cbl		= ATA_CBL_SATA },
6286 		{ "1.5Gbps",	.spd_limit	= 1 },
6287 		{ "3.0Gbps",	.spd_limit	= 2 },
6288 		{ "noncq",	.horkage_on	= ATA_HORKAGE_NONCQ },
6289 		{ "ncq",	.horkage_off	= ATA_HORKAGE_NONCQ },
6290 		{ "dump_id",	.horkage_on	= ATA_HORKAGE_DUMP_ID },
6291 		{ "pio0",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 0) },
6292 		{ "pio1",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 1) },
6293 		{ "pio2",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 2) },
6294 		{ "pio3",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 3) },
6295 		{ "pio4",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 4) },
6296 		{ "pio5",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 5) },
6297 		{ "pio6",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 6) },
6298 		{ "mwdma0",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 0) },
6299 		{ "mwdma1",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 1) },
6300 		{ "mwdma2",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 2) },
6301 		{ "mwdma3",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 3) },
6302 		{ "mwdma4",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 4) },
6303 		{ "udma0",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 0) },
6304 		{ "udma16",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 0) },
6305 		{ "udma/16",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 0) },
6306 		{ "udma1",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 1) },
6307 		{ "udma25",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 1) },
6308 		{ "udma/25",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 1) },
6309 		{ "udma2",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 2) },
6310 		{ "udma33",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 2) },
6311 		{ "udma/33",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 2) },
6312 		{ "udma3",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 3) },
6313 		{ "udma44",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 3) },
6314 		{ "udma/44",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 3) },
6315 		{ "udma4",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 4) },
6316 		{ "udma66",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 4) },
6317 		{ "udma/66",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 4) },
6318 		{ "udma5",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 5) },
6319 		{ "udma100",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 5) },
6320 		{ "udma/100",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 5) },
6321 		{ "udma6",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 6) },
6322 		{ "udma133",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 6) },
6323 		{ "udma/133",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 6) },
6324 		{ "udma7",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 7) },
6325 		{ "nohrst",	.lflags		= ATA_LFLAG_NO_HRST },
6326 		{ "nosrst",	.lflags		= ATA_LFLAG_NO_SRST },
6327 		{ "norst",	.lflags		= ATA_LFLAG_NO_HRST | ATA_LFLAG_NO_SRST },
6328 	};
6329 	char *start = *cur, *p = *cur;
6330 	char *id, *val, *endp;
6331 	const struct ata_force_param *match_fp = NULL;
6332 	int nr_matches = 0, i;
6333 
6334 	/* find where this param ends and update *cur */
6335 	while (*p != '\0' && *p != ',')
6336 		p++;
6337 
6338 	if (*p == '\0')
6339 		*cur = p;
6340 	else
6341 		*cur = p + 1;
6342 
6343 	*p = '\0';
6344 
6345 	/* parse */
6346 	p = strchr(start, ':');
6347 	if (!p) {
6348 		val = strstrip(start);
6349 		goto parse_val;
6350 	}
6351 	*p = '\0';
6352 
6353 	id = strstrip(start);
6354 	val = strstrip(p + 1);
6355 
6356 	/* parse id */
6357 	p = strchr(id, '.');
6358 	if (p) {
6359 		*p++ = '\0';
6360 		force_ent->device = simple_strtoul(p, &endp, 10);
6361 		if (p == endp || *endp != '\0') {
6362 			*reason = "invalid device";
6363 			return -EINVAL;
6364 		}
6365 	}
6366 
6367 	force_ent->port = simple_strtoul(id, &endp, 10);
6368 	if (p == endp || *endp != '\0') {
6369 		*reason = "invalid port/link";
6370 		return -EINVAL;
6371 	}
6372 
6373  parse_val:
6374 	/* parse val, allow shortcuts so that both 1.5 and 1.5Gbps work */
6375 	for (i = 0; i < ARRAY_SIZE(force_tbl); i++) {
6376 		const struct ata_force_param *fp = &force_tbl[i];
6377 
6378 		if (strncasecmp(val, fp->name, strlen(val)))
6379 			continue;
6380 
6381 		nr_matches++;
6382 		match_fp = fp;
6383 
6384 		if (strcasecmp(val, fp->name) == 0) {
6385 			nr_matches = 1;
6386 			break;
6387 		}
6388 	}
6389 
6390 	if (!nr_matches) {
6391 		*reason = "unknown value";
6392 		return -EINVAL;
6393 	}
6394 	if (nr_matches > 1) {
6395 		*reason = "ambigious value";
6396 		return -EINVAL;
6397 	}
6398 
6399 	force_ent->param = *match_fp;
6400 
6401 	return 0;
6402 }
6403 
6404 static void __init ata_parse_force_param(void)
6405 {
6406 	int idx = 0, size = 1;
6407 	int last_port = -1, last_device = -1;
6408 	char *p, *cur, *next;
6409 
6410 	/* calculate maximum number of params and allocate force_tbl */
6411 	for (p = ata_force_param_buf; *p; p++)
6412 		if (*p == ',')
6413 			size++;
6414 
6415 	ata_force_tbl = kzalloc(sizeof(ata_force_tbl[0]) * size, GFP_KERNEL);
6416 	if (!ata_force_tbl) {
6417 		printk(KERN_WARNING "ata: failed to extend force table, "
6418 		       "libata.force ignored\n");
6419 		return;
6420 	}
6421 
6422 	/* parse and populate the table */
6423 	for (cur = ata_force_param_buf; *cur != '\0'; cur = next) {
6424 		const char *reason = "";
6425 		struct ata_force_ent te = { .port = -1, .device = -1 };
6426 
6427 		next = cur;
6428 		if (ata_parse_force_one(&next, &te, &reason)) {
6429 			printk(KERN_WARNING "ata: failed to parse force "
6430 			       "parameter \"%s\" (%s)\n",
6431 			       cur, reason);
6432 			continue;
6433 		}
6434 
6435 		if (te.port == -1) {
6436 			te.port = last_port;
6437 			te.device = last_device;
6438 		}
6439 
6440 		ata_force_tbl[idx++] = te;
6441 
6442 		last_port = te.port;
6443 		last_device = te.device;
6444 	}
6445 
6446 	ata_force_tbl_size = idx;
6447 }
6448 
6449 static int __init ata_init(void)
6450 {
6451 	int rc;
6452 
6453 	ata_parse_force_param();
6454 
6455 	rc = ata_sff_init();
6456 	if (rc) {
6457 		kfree(ata_force_tbl);
6458 		return rc;
6459 	}
6460 
6461 	libata_transport_init();
6462 	ata_scsi_transport_template = ata_attach_transport();
6463 	if (!ata_scsi_transport_template) {
6464 		ata_sff_exit();
6465 		rc = -ENOMEM;
6466 		goto err_out;
6467 	}
6468 
6469 	printk(KERN_DEBUG "libata version " DRV_VERSION " loaded.\n");
6470 	return 0;
6471 
6472 err_out:
6473 	return rc;
6474 }
6475 
6476 static void __exit ata_exit(void)
6477 {
6478 	ata_release_transport(ata_scsi_transport_template);
6479 	libata_transport_exit();
6480 	ata_sff_exit();
6481 	kfree(ata_force_tbl);
6482 }
6483 
6484 subsys_initcall(ata_init);
6485 module_exit(ata_exit);
6486 
6487 static DEFINE_RATELIMIT_STATE(ratelimit, HZ / 5, 1);
6488 
6489 int ata_ratelimit(void)
6490 {
6491 	return __ratelimit(&ratelimit);
6492 }
6493 
6494 /**
6495  *	ata_msleep - ATA EH owner aware msleep
6496  *	@ap: ATA port to attribute the sleep to
6497  *	@msecs: duration to sleep in milliseconds
6498  *
6499  *	Sleeps @msecs.  If the current task is owner of @ap's EH, the
6500  *	ownership is released before going to sleep and reacquired
6501  *	after the sleep is complete.  IOW, other ports sharing the
6502  *	@ap->host will be allowed to own the EH while this task is
6503  *	sleeping.
6504  *
6505  *	LOCKING:
6506  *	Might sleep.
6507  */
6508 void ata_msleep(struct ata_port *ap, unsigned int msecs)
6509 {
6510 	bool owns_eh = ap && ap->host->eh_owner == current;
6511 
6512 	if (owns_eh)
6513 		ata_eh_release(ap);
6514 
6515 	msleep(msecs);
6516 
6517 	if (owns_eh)
6518 		ata_eh_acquire(ap);
6519 }
6520 
6521 /**
6522  *	ata_wait_register - wait until register value changes
6523  *	@ap: ATA port to wait register for, can be NULL
6524  *	@reg: IO-mapped register
6525  *	@mask: Mask to apply to read register value
6526  *	@val: Wait condition
6527  *	@interval: polling interval in milliseconds
6528  *	@timeout: timeout in milliseconds
6529  *
6530  *	Waiting for some bits of register to change is a common
6531  *	operation for ATA controllers.  This function reads 32bit LE
6532  *	IO-mapped register @reg and tests for the following condition.
6533  *
6534  *	(*@reg & mask) != val
6535  *
6536  *	If the condition is met, it returns; otherwise, the process is
6537  *	repeated after @interval_msec until timeout.
6538  *
6539  *	LOCKING:
6540  *	Kernel thread context (may sleep)
6541  *
6542  *	RETURNS:
6543  *	The final register value.
6544  */
6545 u32 ata_wait_register(struct ata_port *ap, void __iomem *reg, u32 mask, u32 val,
6546 		      unsigned long interval, unsigned long timeout)
6547 {
6548 	unsigned long deadline;
6549 	u32 tmp;
6550 
6551 	tmp = ioread32(reg);
6552 
6553 	/* Calculate timeout _after_ the first read to make sure
6554 	 * preceding writes reach the controller before starting to
6555 	 * eat away the timeout.
6556 	 */
6557 	deadline = ata_deadline(jiffies, timeout);
6558 
6559 	while ((tmp & mask) == val && time_before(jiffies, deadline)) {
6560 		ata_msleep(ap, interval);
6561 		tmp = ioread32(reg);
6562 	}
6563 
6564 	return tmp;
6565 }
6566 
6567 /*
6568  * Dummy port_ops
6569  */
6570 static unsigned int ata_dummy_qc_issue(struct ata_queued_cmd *qc)
6571 {
6572 	return AC_ERR_SYSTEM;
6573 }
6574 
6575 static void ata_dummy_error_handler(struct ata_port *ap)
6576 {
6577 	/* truly dummy */
6578 }
6579 
6580 struct ata_port_operations ata_dummy_port_ops = {
6581 	.qc_prep		= ata_noop_qc_prep,
6582 	.qc_issue		= ata_dummy_qc_issue,
6583 	.error_handler		= ata_dummy_error_handler,
6584 };
6585 
6586 const struct ata_port_info ata_dummy_port_info = {
6587 	.port_ops		= &ata_dummy_port_ops,
6588 };
6589 
6590 /*
6591  * libata is essentially a library of internal helper functions for
6592  * low-level ATA host controller drivers.  As such, the API/ABI is
6593  * likely to change as new drivers are added and updated.
6594  * Do not depend on ABI/API stability.
6595  */
6596 EXPORT_SYMBOL_GPL(sata_deb_timing_normal);
6597 EXPORT_SYMBOL_GPL(sata_deb_timing_hotplug);
6598 EXPORT_SYMBOL_GPL(sata_deb_timing_long);
6599 EXPORT_SYMBOL_GPL(ata_base_port_ops);
6600 EXPORT_SYMBOL_GPL(sata_port_ops);
6601 EXPORT_SYMBOL_GPL(ata_dummy_port_ops);
6602 EXPORT_SYMBOL_GPL(ata_dummy_port_info);
6603 EXPORT_SYMBOL_GPL(ata_link_next);
6604 EXPORT_SYMBOL_GPL(ata_dev_next);
6605 EXPORT_SYMBOL_GPL(ata_std_bios_param);
6606 EXPORT_SYMBOL_GPL(ata_scsi_unlock_native_capacity);
6607 EXPORT_SYMBOL_GPL(ata_host_init);
6608 EXPORT_SYMBOL_GPL(ata_host_alloc);
6609 EXPORT_SYMBOL_GPL(ata_host_alloc_pinfo);
6610 EXPORT_SYMBOL_GPL(ata_slave_link_init);
6611 EXPORT_SYMBOL_GPL(ata_host_start);
6612 EXPORT_SYMBOL_GPL(ata_host_register);
6613 EXPORT_SYMBOL_GPL(ata_host_activate);
6614 EXPORT_SYMBOL_GPL(ata_host_detach);
6615 EXPORT_SYMBOL_GPL(ata_sg_init);
6616 EXPORT_SYMBOL_GPL(ata_qc_complete);
6617 EXPORT_SYMBOL_GPL(ata_qc_complete_multiple);
6618 EXPORT_SYMBOL_GPL(atapi_cmd_type);
6619 EXPORT_SYMBOL_GPL(ata_tf_to_fis);
6620 EXPORT_SYMBOL_GPL(ata_tf_from_fis);
6621 EXPORT_SYMBOL_GPL(ata_pack_xfermask);
6622 EXPORT_SYMBOL_GPL(ata_unpack_xfermask);
6623 EXPORT_SYMBOL_GPL(ata_xfer_mask2mode);
6624 EXPORT_SYMBOL_GPL(ata_xfer_mode2mask);
6625 EXPORT_SYMBOL_GPL(ata_xfer_mode2shift);
6626 EXPORT_SYMBOL_GPL(ata_mode_string);
6627 EXPORT_SYMBOL_GPL(ata_id_xfermask);
6628 EXPORT_SYMBOL_GPL(ata_do_set_mode);
6629 EXPORT_SYMBOL_GPL(ata_std_qc_defer);
6630 EXPORT_SYMBOL_GPL(ata_noop_qc_prep);
6631 EXPORT_SYMBOL_GPL(ata_dev_disable);
6632 EXPORT_SYMBOL_GPL(sata_set_spd);
6633 EXPORT_SYMBOL_GPL(ata_wait_after_reset);
6634 EXPORT_SYMBOL_GPL(sata_link_debounce);
6635 EXPORT_SYMBOL_GPL(sata_link_resume);
6636 EXPORT_SYMBOL_GPL(sata_link_scr_lpm);
6637 EXPORT_SYMBOL_GPL(ata_std_prereset);
6638 EXPORT_SYMBOL_GPL(sata_link_hardreset);
6639 EXPORT_SYMBOL_GPL(sata_std_hardreset);
6640 EXPORT_SYMBOL_GPL(ata_std_postreset);
6641 EXPORT_SYMBOL_GPL(ata_dev_classify);
6642 EXPORT_SYMBOL_GPL(ata_dev_pair);
6643 EXPORT_SYMBOL_GPL(ata_ratelimit);
6644 EXPORT_SYMBOL_GPL(ata_msleep);
6645 EXPORT_SYMBOL_GPL(ata_wait_register);
6646 EXPORT_SYMBOL_GPL(ata_scsi_queuecmd);
6647 EXPORT_SYMBOL_GPL(ata_scsi_slave_config);
6648 EXPORT_SYMBOL_GPL(ata_scsi_slave_destroy);
6649 EXPORT_SYMBOL_GPL(ata_scsi_change_queue_depth);
6650 EXPORT_SYMBOL_GPL(sata_scr_valid);
6651 EXPORT_SYMBOL_GPL(sata_scr_read);
6652 EXPORT_SYMBOL_GPL(sata_scr_write);
6653 EXPORT_SYMBOL_GPL(sata_scr_write_flush);
6654 EXPORT_SYMBOL_GPL(ata_link_online);
6655 EXPORT_SYMBOL_GPL(ata_link_offline);
6656 #ifdef CONFIG_PM
6657 EXPORT_SYMBOL_GPL(ata_host_suspend);
6658 EXPORT_SYMBOL_GPL(ata_host_resume);
6659 #endif /* CONFIG_PM */
6660 EXPORT_SYMBOL_GPL(ata_id_string);
6661 EXPORT_SYMBOL_GPL(ata_id_c_string);
6662 EXPORT_SYMBOL_GPL(ata_do_dev_read_id);
6663 EXPORT_SYMBOL_GPL(ata_scsi_simulate);
6664 
6665 EXPORT_SYMBOL_GPL(ata_pio_need_iordy);
6666 EXPORT_SYMBOL_GPL(ata_timing_find_mode);
6667 EXPORT_SYMBOL_GPL(ata_timing_compute);
6668 EXPORT_SYMBOL_GPL(ata_timing_merge);
6669 EXPORT_SYMBOL_GPL(ata_timing_cycle2mode);
6670 
6671 #ifdef CONFIG_PCI
6672 EXPORT_SYMBOL_GPL(pci_test_config_bits);
6673 EXPORT_SYMBOL_GPL(ata_pci_remove_one);
6674 #ifdef CONFIG_PM
6675 EXPORT_SYMBOL_GPL(ata_pci_device_do_suspend);
6676 EXPORT_SYMBOL_GPL(ata_pci_device_do_resume);
6677 EXPORT_SYMBOL_GPL(ata_pci_device_suspend);
6678 EXPORT_SYMBOL_GPL(ata_pci_device_resume);
6679 #endif /* CONFIG_PM */
6680 #endif /* CONFIG_PCI */
6681 
6682 EXPORT_SYMBOL_GPL(__ata_ehi_push_desc);
6683 EXPORT_SYMBOL_GPL(ata_ehi_push_desc);
6684 EXPORT_SYMBOL_GPL(ata_ehi_clear_desc);
6685 EXPORT_SYMBOL_GPL(ata_port_desc);
6686 #ifdef CONFIG_PCI
6687 EXPORT_SYMBOL_GPL(ata_port_pbar_desc);
6688 #endif /* CONFIG_PCI */
6689 EXPORT_SYMBOL_GPL(ata_port_schedule_eh);
6690 EXPORT_SYMBOL_GPL(ata_link_abort);
6691 EXPORT_SYMBOL_GPL(ata_port_abort);
6692 EXPORT_SYMBOL_GPL(ata_port_freeze);
6693 EXPORT_SYMBOL_GPL(sata_async_notification);
6694 EXPORT_SYMBOL_GPL(ata_eh_freeze_port);
6695 EXPORT_SYMBOL_GPL(ata_eh_thaw_port);
6696 EXPORT_SYMBOL_GPL(ata_eh_qc_complete);
6697 EXPORT_SYMBOL_GPL(ata_eh_qc_retry);
6698 EXPORT_SYMBOL_GPL(ata_eh_analyze_ncq_error);
6699 EXPORT_SYMBOL_GPL(ata_do_eh);
6700 EXPORT_SYMBOL_GPL(ata_std_error_handler);
6701 
6702 EXPORT_SYMBOL_GPL(ata_cable_40wire);
6703 EXPORT_SYMBOL_GPL(ata_cable_80wire);
6704 EXPORT_SYMBOL_GPL(ata_cable_unknown);
6705 EXPORT_SYMBOL_GPL(ata_cable_ignore);
6706 EXPORT_SYMBOL_GPL(ata_cable_sata);
6707