xref: /openbmc/linux/drivers/ata/libata-core.c (revision db181ce0)
1 /*
2  *  libata-core.c - helper library for ATA
3  *
4  *  Maintained by:  Tejun Heo <tj@kernel.org>
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 #include <linux/pm_runtime.h>
70 #include <linux/platform_device.h>
71 
72 #include "libata.h"
73 #include "libata-transport.h"
74 
75 /* debounce timing parameters in msecs { interval, duration, timeout } */
76 const unsigned long sata_deb_timing_normal[]		= {   5,  100, 2000 };
77 const unsigned long sata_deb_timing_hotplug[]		= {  25,  500, 2000 };
78 const unsigned long sata_deb_timing_long[]		= { 100, 2000, 5000 };
79 
80 const struct ata_port_operations ata_base_port_ops = {
81 	.prereset		= ata_std_prereset,
82 	.postreset		= ata_std_postreset,
83 	.error_handler		= ata_std_error_handler,
84 	.sched_eh		= ata_std_sched_eh,
85 	.end_eh			= ata_std_end_eh,
86 };
87 
88 const struct ata_port_operations sata_port_ops = {
89 	.inherits		= &ata_base_port_ops,
90 
91 	.qc_defer		= ata_std_qc_defer,
92 	.hardreset		= sata_std_hardreset,
93 };
94 
95 static unsigned int ata_dev_init_params(struct ata_device *dev,
96 					u16 heads, u16 sectors);
97 static unsigned int ata_dev_set_xfermode(struct ata_device *dev);
98 static void ata_dev_xfermask(struct ata_device *dev);
99 static unsigned long ata_dev_blacklisted(const struct ata_device *dev);
100 
101 atomic_t ata_print_id = ATOMIC_INIT(0);
102 
103 struct ata_force_param {
104 	const char	*name;
105 	unsigned int	cbl;
106 	int		spd_limit;
107 	unsigned long	xfer_mask;
108 	unsigned int	horkage_on;
109 	unsigned int	horkage_off;
110 	unsigned int	lflags;
111 };
112 
113 struct ata_force_ent {
114 	int			port;
115 	int			device;
116 	struct ata_force_param	param;
117 };
118 
119 static struct ata_force_ent *ata_force_tbl;
120 static int ata_force_tbl_size;
121 
122 static char ata_force_param_buf[PAGE_SIZE] __initdata;
123 /* param_buf is thrown away after initialization, disallow read */
124 module_param_string(force, ata_force_param_buf, sizeof(ata_force_param_buf), 0);
125 MODULE_PARM_DESC(force, "Force ATA configurations including cable type, link speed and transfer mode (see Documentation/kernel-parameters.txt for details)");
126 
127 static int atapi_enabled = 1;
128 module_param(atapi_enabled, int, 0444);
129 MODULE_PARM_DESC(atapi_enabled, "Enable discovery of ATAPI devices (0=off, 1=on [default])");
130 
131 static int atapi_dmadir = 0;
132 module_param(atapi_dmadir, int, 0444);
133 MODULE_PARM_DESC(atapi_dmadir, "Enable ATAPI DMADIR bridge support (0=off [default], 1=on)");
134 
135 int atapi_passthru16 = 1;
136 module_param(atapi_passthru16, int, 0444);
137 MODULE_PARM_DESC(atapi_passthru16, "Enable ATA_16 passthru for ATAPI devices (0=off, 1=on [default])");
138 
139 int libata_fua = 0;
140 module_param_named(fua, libata_fua, int, 0444);
141 MODULE_PARM_DESC(fua, "FUA support (0=off [default], 1=on)");
142 
143 static int ata_ignore_hpa;
144 module_param_named(ignore_hpa, ata_ignore_hpa, int, 0644);
145 MODULE_PARM_DESC(ignore_hpa, "Ignore HPA limit (0=keep BIOS limits, 1=ignore limits, using full disk)");
146 
147 static int libata_dma_mask = ATA_DMA_MASK_ATA|ATA_DMA_MASK_ATAPI|ATA_DMA_MASK_CFA;
148 module_param_named(dma, libata_dma_mask, int, 0444);
149 MODULE_PARM_DESC(dma, "DMA enable/disable (0x1==ATA, 0x2==ATAPI, 0x4==CF)");
150 
151 static int ata_probe_timeout;
152 module_param(ata_probe_timeout, int, 0444);
153 MODULE_PARM_DESC(ata_probe_timeout, "Set ATA probing timeout (seconds)");
154 
155 int libata_noacpi = 0;
156 module_param_named(noacpi, libata_noacpi, int, 0444);
157 MODULE_PARM_DESC(noacpi, "Disable the use of ACPI in probe/suspend/resume (0=off [default], 1=on)");
158 
159 int libata_allow_tpm = 0;
160 module_param_named(allow_tpm, libata_allow_tpm, int, 0444);
161 MODULE_PARM_DESC(allow_tpm, "Permit the use of TPM commands (0=off [default], 1=on)");
162 
163 static int atapi_an;
164 module_param(atapi_an, int, 0444);
165 MODULE_PARM_DESC(atapi_an, "Enable ATAPI AN media presence notification (0=0ff [default], 1=on)");
166 
167 MODULE_AUTHOR("Jeff Garzik");
168 MODULE_DESCRIPTION("Library module for ATA devices");
169 MODULE_LICENSE("GPL");
170 MODULE_VERSION(DRV_VERSION);
171 
172 
173 static bool ata_sstatus_online(u32 sstatus)
174 {
175 	return (sstatus & 0xf) == 0x3;
176 }
177 
178 /**
179  *	ata_link_next - link iteration helper
180  *	@link: the previous link, NULL to start
181  *	@ap: ATA port containing links to iterate
182  *	@mode: iteration mode, one of ATA_LITER_*
183  *
184  *	LOCKING:
185  *	Host lock or EH context.
186  *
187  *	RETURNS:
188  *	Pointer to the next link.
189  */
190 struct ata_link *ata_link_next(struct ata_link *link, struct ata_port *ap,
191 			       enum ata_link_iter_mode mode)
192 {
193 	BUG_ON(mode != ATA_LITER_EDGE &&
194 	       mode != ATA_LITER_PMP_FIRST && mode != ATA_LITER_HOST_FIRST);
195 
196 	/* NULL link indicates start of iteration */
197 	if (!link)
198 		switch (mode) {
199 		case ATA_LITER_EDGE:
200 		case ATA_LITER_PMP_FIRST:
201 			if (sata_pmp_attached(ap))
202 				return ap->pmp_link;
203 			/* fall through */
204 		case ATA_LITER_HOST_FIRST:
205 			return &ap->link;
206 		}
207 
208 	/* we just iterated over the host link, what's next? */
209 	if (link == &ap->link)
210 		switch (mode) {
211 		case ATA_LITER_HOST_FIRST:
212 			if (sata_pmp_attached(ap))
213 				return ap->pmp_link;
214 			/* fall through */
215 		case ATA_LITER_PMP_FIRST:
216 			if (unlikely(ap->slave_link))
217 				return ap->slave_link;
218 			/* fall through */
219 		case ATA_LITER_EDGE:
220 			return NULL;
221 		}
222 
223 	/* slave_link excludes PMP */
224 	if (unlikely(link == ap->slave_link))
225 		return NULL;
226 
227 	/* we were over a PMP link */
228 	if (++link < ap->pmp_link + ap->nr_pmp_links)
229 		return link;
230 
231 	if (mode == ATA_LITER_PMP_FIRST)
232 		return &ap->link;
233 
234 	return NULL;
235 }
236 
237 /**
238  *	ata_dev_next - device iteration helper
239  *	@dev: the previous device, NULL to start
240  *	@link: ATA link containing devices to iterate
241  *	@mode: iteration mode, one of ATA_DITER_*
242  *
243  *	LOCKING:
244  *	Host lock or EH context.
245  *
246  *	RETURNS:
247  *	Pointer to the next device.
248  */
249 struct ata_device *ata_dev_next(struct ata_device *dev, struct ata_link *link,
250 				enum ata_dev_iter_mode mode)
251 {
252 	BUG_ON(mode != ATA_DITER_ENABLED && mode != ATA_DITER_ENABLED_REVERSE &&
253 	       mode != ATA_DITER_ALL && mode != ATA_DITER_ALL_REVERSE);
254 
255 	/* NULL dev indicates start of iteration */
256 	if (!dev)
257 		switch (mode) {
258 		case ATA_DITER_ENABLED:
259 		case ATA_DITER_ALL:
260 			dev = link->device;
261 			goto check;
262 		case ATA_DITER_ENABLED_REVERSE:
263 		case ATA_DITER_ALL_REVERSE:
264 			dev = link->device + ata_link_max_devices(link) - 1;
265 			goto check;
266 		}
267 
268  next:
269 	/* move to the next one */
270 	switch (mode) {
271 	case ATA_DITER_ENABLED:
272 	case ATA_DITER_ALL:
273 		if (++dev < link->device + ata_link_max_devices(link))
274 			goto check;
275 		return NULL;
276 	case ATA_DITER_ENABLED_REVERSE:
277 	case ATA_DITER_ALL_REVERSE:
278 		if (--dev >= link->device)
279 			goto check;
280 		return NULL;
281 	}
282 
283  check:
284 	if ((mode == ATA_DITER_ENABLED || mode == ATA_DITER_ENABLED_REVERSE) &&
285 	    !ata_dev_enabled(dev))
286 		goto next;
287 	return dev;
288 }
289 
290 /**
291  *	ata_dev_phys_link - find physical link for a device
292  *	@dev: ATA device to look up physical link for
293  *
294  *	Look up physical link which @dev is attached to.  Note that
295  *	this is different from @dev->link only when @dev is on slave
296  *	link.  For all other cases, it's the same as @dev->link.
297  *
298  *	LOCKING:
299  *	Don't care.
300  *
301  *	RETURNS:
302  *	Pointer to the found physical link.
303  */
304 struct ata_link *ata_dev_phys_link(struct ata_device *dev)
305 {
306 	struct ata_port *ap = dev->link->ap;
307 
308 	if (!ap->slave_link)
309 		return dev->link;
310 	if (!dev->devno)
311 		return &ap->link;
312 	return ap->slave_link;
313 }
314 
315 /**
316  *	ata_force_cbl - force cable type according to libata.force
317  *	@ap: ATA port of interest
318  *
319  *	Force cable type according to libata.force and whine about it.
320  *	The last entry which has matching port number is used, so it
321  *	can be specified as part of device force parameters.  For
322  *	example, both "a:40c,1.00:udma4" and "1.00:40c,udma4" have the
323  *	same effect.
324  *
325  *	LOCKING:
326  *	EH context.
327  */
328 void ata_force_cbl(struct ata_port *ap)
329 {
330 	int i;
331 
332 	for (i = ata_force_tbl_size - 1; i >= 0; i--) {
333 		const struct ata_force_ent *fe = &ata_force_tbl[i];
334 
335 		if (fe->port != -1 && fe->port != ap->print_id)
336 			continue;
337 
338 		if (fe->param.cbl == ATA_CBL_NONE)
339 			continue;
340 
341 		ap->cbl = fe->param.cbl;
342 		ata_port_notice(ap, "FORCE: cable set to %s\n", fe->param.name);
343 		return;
344 	}
345 }
346 
347 /**
348  *	ata_force_link_limits - force link limits according to libata.force
349  *	@link: ATA link of interest
350  *
351  *	Force link flags and SATA spd limit according to libata.force
352  *	and whine about it.  When only the port part is specified
353  *	(e.g. 1:), the limit applies to all links connected to both
354  *	the host link and all fan-out ports connected via PMP.  If the
355  *	device part is specified as 0 (e.g. 1.00:), it specifies the
356  *	first fan-out link not the host link.  Device number 15 always
357  *	points to the host link whether PMP is attached or not.  If the
358  *	controller has slave link, device number 16 points to it.
359  *
360  *	LOCKING:
361  *	EH context.
362  */
363 static void ata_force_link_limits(struct ata_link *link)
364 {
365 	bool did_spd = false;
366 	int linkno = link->pmp;
367 	int i;
368 
369 	if (ata_is_host_link(link))
370 		linkno += 15;
371 
372 	for (i = ata_force_tbl_size - 1; i >= 0; i--) {
373 		const struct ata_force_ent *fe = &ata_force_tbl[i];
374 
375 		if (fe->port != -1 && fe->port != link->ap->print_id)
376 			continue;
377 
378 		if (fe->device != -1 && fe->device != linkno)
379 			continue;
380 
381 		/* only honor the first spd limit */
382 		if (!did_spd && fe->param.spd_limit) {
383 			link->hw_sata_spd_limit = (1 << fe->param.spd_limit) - 1;
384 			ata_link_notice(link, "FORCE: PHY spd limit set to %s\n",
385 					fe->param.name);
386 			did_spd = true;
387 		}
388 
389 		/* let lflags stack */
390 		if (fe->param.lflags) {
391 			link->flags |= fe->param.lflags;
392 			ata_link_notice(link,
393 					"FORCE: link flag 0x%x forced -> 0x%x\n",
394 					fe->param.lflags, link->flags);
395 		}
396 	}
397 }
398 
399 /**
400  *	ata_force_xfermask - force xfermask according to libata.force
401  *	@dev: ATA device of interest
402  *
403  *	Force xfer_mask according to libata.force and whine about it.
404  *	For consistency with link selection, device number 15 selects
405  *	the first device connected to the host link.
406  *
407  *	LOCKING:
408  *	EH context.
409  */
410 static void ata_force_xfermask(struct ata_device *dev)
411 {
412 	int devno = dev->link->pmp + dev->devno;
413 	int alt_devno = devno;
414 	int i;
415 
416 	/* allow n.15/16 for devices attached to host port */
417 	if (ata_is_host_link(dev->link))
418 		alt_devno += 15;
419 
420 	for (i = ata_force_tbl_size - 1; i >= 0; i--) {
421 		const struct ata_force_ent *fe = &ata_force_tbl[i];
422 		unsigned long pio_mask, mwdma_mask, udma_mask;
423 
424 		if (fe->port != -1 && fe->port != dev->link->ap->print_id)
425 			continue;
426 
427 		if (fe->device != -1 && fe->device != devno &&
428 		    fe->device != alt_devno)
429 			continue;
430 
431 		if (!fe->param.xfer_mask)
432 			continue;
433 
434 		ata_unpack_xfermask(fe->param.xfer_mask,
435 				    &pio_mask, &mwdma_mask, &udma_mask);
436 		if (udma_mask)
437 			dev->udma_mask = udma_mask;
438 		else if (mwdma_mask) {
439 			dev->udma_mask = 0;
440 			dev->mwdma_mask = mwdma_mask;
441 		} else {
442 			dev->udma_mask = 0;
443 			dev->mwdma_mask = 0;
444 			dev->pio_mask = pio_mask;
445 		}
446 
447 		ata_dev_notice(dev, "FORCE: xfer_mask set to %s\n",
448 			       fe->param.name);
449 		return;
450 	}
451 }
452 
453 /**
454  *	ata_force_horkage - force horkage according to libata.force
455  *	@dev: ATA device of interest
456  *
457  *	Force horkage according to libata.force and whine about it.
458  *	For consistency with link selection, device number 15 selects
459  *	the first device connected to the host link.
460  *
461  *	LOCKING:
462  *	EH context.
463  */
464 static void ata_force_horkage(struct ata_device *dev)
465 {
466 	int devno = dev->link->pmp + dev->devno;
467 	int alt_devno = devno;
468 	int i;
469 
470 	/* allow n.15/16 for devices attached to host port */
471 	if (ata_is_host_link(dev->link))
472 		alt_devno += 15;
473 
474 	for (i = 0; i < ata_force_tbl_size; i++) {
475 		const struct ata_force_ent *fe = &ata_force_tbl[i];
476 
477 		if (fe->port != -1 && fe->port != dev->link->ap->print_id)
478 			continue;
479 
480 		if (fe->device != -1 && fe->device != devno &&
481 		    fe->device != alt_devno)
482 			continue;
483 
484 		if (!(~dev->horkage & fe->param.horkage_on) &&
485 		    !(dev->horkage & fe->param.horkage_off))
486 			continue;
487 
488 		dev->horkage |= fe->param.horkage_on;
489 		dev->horkage &= ~fe->param.horkage_off;
490 
491 		ata_dev_notice(dev, "FORCE: horkage modified (%s)\n",
492 			       fe->param.name);
493 	}
494 }
495 
496 /**
497  *	atapi_cmd_type - Determine ATAPI command type from SCSI opcode
498  *	@opcode: SCSI opcode
499  *
500  *	Determine ATAPI command type from @opcode.
501  *
502  *	LOCKING:
503  *	None.
504  *
505  *	RETURNS:
506  *	ATAPI_{READ|WRITE|READ_CD|PASS_THRU|MISC}
507  */
508 int atapi_cmd_type(u8 opcode)
509 {
510 	switch (opcode) {
511 	case GPCMD_READ_10:
512 	case GPCMD_READ_12:
513 		return ATAPI_READ;
514 
515 	case GPCMD_WRITE_10:
516 	case GPCMD_WRITE_12:
517 	case GPCMD_WRITE_AND_VERIFY_10:
518 		return ATAPI_WRITE;
519 
520 	case GPCMD_READ_CD:
521 	case GPCMD_READ_CD_MSF:
522 		return ATAPI_READ_CD;
523 
524 	case ATA_16:
525 	case ATA_12:
526 		if (atapi_passthru16)
527 			return ATAPI_PASS_THRU;
528 		/* fall thru */
529 	default:
530 		return ATAPI_MISC;
531 	}
532 }
533 
534 /**
535  *	ata_tf_to_fis - Convert ATA taskfile to SATA FIS structure
536  *	@tf: Taskfile to convert
537  *	@pmp: Port multiplier port
538  *	@is_cmd: This FIS is for command
539  *	@fis: Buffer into which data will output
540  *
541  *	Converts a standard ATA taskfile to a Serial ATA
542  *	FIS structure (Register - Host to Device).
543  *
544  *	LOCKING:
545  *	Inherited from caller.
546  */
547 void ata_tf_to_fis(const struct ata_taskfile *tf, u8 pmp, int is_cmd, u8 *fis)
548 {
549 	fis[0] = 0x27;			/* Register - Host to Device FIS */
550 	fis[1] = pmp & 0xf;		/* Port multiplier number*/
551 	if (is_cmd)
552 		fis[1] |= (1 << 7);	/* bit 7 indicates Command FIS */
553 
554 	fis[2] = tf->command;
555 	fis[3] = tf->feature;
556 
557 	fis[4] = tf->lbal;
558 	fis[5] = tf->lbam;
559 	fis[6] = tf->lbah;
560 	fis[7] = tf->device;
561 
562 	fis[8] = tf->hob_lbal;
563 	fis[9] = tf->hob_lbam;
564 	fis[10] = tf->hob_lbah;
565 	fis[11] = tf->hob_feature;
566 
567 	fis[12] = tf->nsect;
568 	fis[13] = tf->hob_nsect;
569 	fis[14] = 0;
570 	fis[15] = tf->ctl;
571 
572 	fis[16] = tf->auxiliary & 0xff;
573 	fis[17] = (tf->auxiliary >> 8) & 0xff;
574 	fis[18] = (tf->auxiliary >> 16) & 0xff;
575 	fis[19] = (tf->auxiliary >> 24) & 0xff;
576 }
577 
578 /**
579  *	ata_tf_from_fis - Convert SATA FIS to ATA taskfile
580  *	@fis: Buffer from which data will be input
581  *	@tf: Taskfile to output
582  *
583  *	Converts a serial ATA FIS structure to a standard ATA taskfile.
584  *
585  *	LOCKING:
586  *	Inherited from caller.
587  */
588 
589 void ata_tf_from_fis(const u8 *fis, struct ata_taskfile *tf)
590 {
591 	tf->command	= fis[2];	/* status */
592 	tf->feature	= fis[3];	/* error */
593 
594 	tf->lbal	= fis[4];
595 	tf->lbam	= fis[5];
596 	tf->lbah	= fis[6];
597 	tf->device	= fis[7];
598 
599 	tf->hob_lbal	= fis[8];
600 	tf->hob_lbam	= fis[9];
601 	tf->hob_lbah	= fis[10];
602 
603 	tf->nsect	= fis[12];
604 	tf->hob_nsect	= fis[13];
605 }
606 
607 static const u8 ata_rw_cmds[] = {
608 	/* pio multi */
609 	ATA_CMD_READ_MULTI,
610 	ATA_CMD_WRITE_MULTI,
611 	ATA_CMD_READ_MULTI_EXT,
612 	ATA_CMD_WRITE_MULTI_EXT,
613 	0,
614 	0,
615 	0,
616 	ATA_CMD_WRITE_MULTI_FUA_EXT,
617 	/* pio */
618 	ATA_CMD_PIO_READ,
619 	ATA_CMD_PIO_WRITE,
620 	ATA_CMD_PIO_READ_EXT,
621 	ATA_CMD_PIO_WRITE_EXT,
622 	0,
623 	0,
624 	0,
625 	0,
626 	/* dma */
627 	ATA_CMD_READ,
628 	ATA_CMD_WRITE,
629 	ATA_CMD_READ_EXT,
630 	ATA_CMD_WRITE_EXT,
631 	0,
632 	0,
633 	0,
634 	ATA_CMD_WRITE_FUA_EXT
635 };
636 
637 /**
638  *	ata_rwcmd_protocol - set taskfile r/w commands and protocol
639  *	@tf: command to examine and configure
640  *	@dev: device tf belongs to
641  *
642  *	Examine the device configuration and tf->flags to calculate
643  *	the proper read/write commands and protocol to use.
644  *
645  *	LOCKING:
646  *	caller.
647  */
648 static int ata_rwcmd_protocol(struct ata_taskfile *tf, struct ata_device *dev)
649 {
650 	u8 cmd;
651 
652 	int index, fua, lba48, write;
653 
654 	fua = (tf->flags & ATA_TFLAG_FUA) ? 4 : 0;
655 	lba48 = (tf->flags & ATA_TFLAG_LBA48) ? 2 : 0;
656 	write = (tf->flags & ATA_TFLAG_WRITE) ? 1 : 0;
657 
658 	if (dev->flags & ATA_DFLAG_PIO) {
659 		tf->protocol = ATA_PROT_PIO;
660 		index = dev->multi_count ? 0 : 8;
661 	} else if (lba48 && (dev->link->ap->flags & ATA_FLAG_PIO_LBA48)) {
662 		/* Unable to use DMA due to host limitation */
663 		tf->protocol = ATA_PROT_PIO;
664 		index = dev->multi_count ? 0 : 8;
665 	} else {
666 		tf->protocol = ATA_PROT_DMA;
667 		index = 16;
668 	}
669 
670 	cmd = ata_rw_cmds[index + fua + lba48 + write];
671 	if (cmd) {
672 		tf->command = cmd;
673 		return 0;
674 	}
675 	return -1;
676 }
677 
678 /**
679  *	ata_tf_read_block - Read block address from ATA taskfile
680  *	@tf: ATA taskfile of interest
681  *	@dev: ATA device @tf belongs to
682  *
683  *	LOCKING:
684  *	None.
685  *
686  *	Read block address from @tf.  This function can handle all
687  *	three address formats - LBA, LBA48 and CHS.  tf->protocol and
688  *	flags select the address format to use.
689  *
690  *	RETURNS:
691  *	Block address read from @tf.
692  */
693 u64 ata_tf_read_block(struct ata_taskfile *tf, struct ata_device *dev)
694 {
695 	u64 block = 0;
696 
697 	if (tf->flags & ATA_TFLAG_LBA) {
698 		if (tf->flags & ATA_TFLAG_LBA48) {
699 			block |= (u64)tf->hob_lbah << 40;
700 			block |= (u64)tf->hob_lbam << 32;
701 			block |= (u64)tf->hob_lbal << 24;
702 		} else
703 			block |= (tf->device & 0xf) << 24;
704 
705 		block |= tf->lbah << 16;
706 		block |= tf->lbam << 8;
707 		block |= tf->lbal;
708 	} else {
709 		u32 cyl, head, sect;
710 
711 		cyl = tf->lbam | (tf->lbah << 8);
712 		head = tf->device & 0xf;
713 		sect = tf->lbal;
714 
715 		if (!sect) {
716 			ata_dev_warn(dev,
717 				     "device reported invalid CHS sector 0\n");
718 			sect = 1; /* oh well */
719 		}
720 
721 		block = (cyl * dev->heads + head) * dev->sectors + sect - 1;
722 	}
723 
724 	return block;
725 }
726 
727 /**
728  *	ata_build_rw_tf - Build ATA taskfile for given read/write request
729  *	@tf: Target ATA taskfile
730  *	@dev: ATA device @tf belongs to
731  *	@block: Block address
732  *	@n_block: Number of blocks
733  *	@tf_flags: RW/FUA etc...
734  *	@tag: tag
735  *
736  *	LOCKING:
737  *	None.
738  *
739  *	Build ATA taskfile @tf for read/write request described by
740  *	@block, @n_block, @tf_flags and @tag on @dev.
741  *
742  *	RETURNS:
743  *
744  *	0 on success, -ERANGE if the request is too large for @dev,
745  *	-EINVAL if the request is invalid.
746  */
747 int ata_build_rw_tf(struct ata_taskfile *tf, struct ata_device *dev,
748 		    u64 block, u32 n_block, unsigned int tf_flags,
749 		    unsigned int tag)
750 {
751 	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
752 	tf->flags |= tf_flags;
753 
754 	if (ata_ncq_enabled(dev) && likely(tag != ATA_TAG_INTERNAL)) {
755 		/* yay, NCQ */
756 		if (!lba_48_ok(block, n_block))
757 			return -ERANGE;
758 
759 		tf->protocol = ATA_PROT_NCQ;
760 		tf->flags |= ATA_TFLAG_LBA | ATA_TFLAG_LBA48;
761 
762 		if (tf->flags & ATA_TFLAG_WRITE)
763 			tf->command = ATA_CMD_FPDMA_WRITE;
764 		else
765 			tf->command = ATA_CMD_FPDMA_READ;
766 
767 		tf->nsect = tag << 3;
768 		tf->hob_feature = (n_block >> 8) & 0xff;
769 		tf->feature = n_block & 0xff;
770 
771 		tf->hob_lbah = (block >> 40) & 0xff;
772 		tf->hob_lbam = (block >> 32) & 0xff;
773 		tf->hob_lbal = (block >> 24) & 0xff;
774 		tf->lbah = (block >> 16) & 0xff;
775 		tf->lbam = (block >> 8) & 0xff;
776 		tf->lbal = block & 0xff;
777 
778 		tf->device = ATA_LBA;
779 		if (tf->flags & ATA_TFLAG_FUA)
780 			tf->device |= 1 << 7;
781 	} else if (dev->flags & ATA_DFLAG_LBA) {
782 		tf->flags |= ATA_TFLAG_LBA;
783 
784 		if (lba_28_ok(block, n_block)) {
785 			/* use LBA28 */
786 			tf->device |= (block >> 24) & 0xf;
787 		} else if (lba_48_ok(block, n_block)) {
788 			if (!(dev->flags & ATA_DFLAG_LBA48))
789 				return -ERANGE;
790 
791 			/* use LBA48 */
792 			tf->flags |= ATA_TFLAG_LBA48;
793 
794 			tf->hob_nsect = (n_block >> 8) & 0xff;
795 
796 			tf->hob_lbah = (block >> 40) & 0xff;
797 			tf->hob_lbam = (block >> 32) & 0xff;
798 			tf->hob_lbal = (block >> 24) & 0xff;
799 		} else
800 			/* request too large even for LBA48 */
801 			return -ERANGE;
802 
803 		if (unlikely(ata_rwcmd_protocol(tf, dev) < 0))
804 			return -EINVAL;
805 
806 		tf->nsect = n_block & 0xff;
807 
808 		tf->lbah = (block >> 16) & 0xff;
809 		tf->lbam = (block >> 8) & 0xff;
810 		tf->lbal = block & 0xff;
811 
812 		tf->device |= ATA_LBA;
813 	} else {
814 		/* CHS */
815 		u32 sect, head, cyl, track;
816 
817 		/* The request -may- be too large for CHS addressing. */
818 		if (!lba_28_ok(block, n_block))
819 			return -ERANGE;
820 
821 		if (unlikely(ata_rwcmd_protocol(tf, dev) < 0))
822 			return -EINVAL;
823 
824 		/* Convert LBA to CHS */
825 		track = (u32)block / dev->sectors;
826 		cyl   = track / dev->heads;
827 		head  = track % dev->heads;
828 		sect  = (u32)block % dev->sectors + 1;
829 
830 		DPRINTK("block %u track %u cyl %u head %u sect %u\n",
831 			(u32)block, track, cyl, head, sect);
832 
833 		/* Check whether the converted CHS can fit.
834 		   Cylinder: 0-65535
835 		   Head: 0-15
836 		   Sector: 1-255*/
837 		if ((cyl >> 16) || (head >> 4) || (sect >> 8) || (!sect))
838 			return -ERANGE;
839 
840 		tf->nsect = n_block & 0xff; /* Sector count 0 means 256 sectors */
841 		tf->lbal = sect;
842 		tf->lbam = cyl;
843 		tf->lbah = cyl >> 8;
844 		tf->device |= head;
845 	}
846 
847 	return 0;
848 }
849 
850 /**
851  *	ata_pack_xfermask - Pack pio, mwdma and udma masks into xfer_mask
852  *	@pio_mask: pio_mask
853  *	@mwdma_mask: mwdma_mask
854  *	@udma_mask: udma_mask
855  *
856  *	Pack @pio_mask, @mwdma_mask and @udma_mask into a single
857  *	unsigned int xfer_mask.
858  *
859  *	LOCKING:
860  *	None.
861  *
862  *	RETURNS:
863  *	Packed xfer_mask.
864  */
865 unsigned long ata_pack_xfermask(unsigned long pio_mask,
866 				unsigned long mwdma_mask,
867 				unsigned long udma_mask)
868 {
869 	return ((pio_mask << ATA_SHIFT_PIO) & ATA_MASK_PIO) |
870 		((mwdma_mask << ATA_SHIFT_MWDMA) & ATA_MASK_MWDMA) |
871 		((udma_mask << ATA_SHIFT_UDMA) & ATA_MASK_UDMA);
872 }
873 
874 /**
875  *	ata_unpack_xfermask - Unpack xfer_mask into pio, mwdma and udma masks
876  *	@xfer_mask: xfer_mask to unpack
877  *	@pio_mask: resulting pio_mask
878  *	@mwdma_mask: resulting mwdma_mask
879  *	@udma_mask: resulting udma_mask
880  *
881  *	Unpack @xfer_mask into @pio_mask, @mwdma_mask and @udma_mask.
882  *	Any NULL distination masks will be ignored.
883  */
884 void ata_unpack_xfermask(unsigned long xfer_mask, unsigned long *pio_mask,
885 			 unsigned long *mwdma_mask, unsigned long *udma_mask)
886 {
887 	if (pio_mask)
888 		*pio_mask = (xfer_mask & ATA_MASK_PIO) >> ATA_SHIFT_PIO;
889 	if (mwdma_mask)
890 		*mwdma_mask = (xfer_mask & ATA_MASK_MWDMA) >> ATA_SHIFT_MWDMA;
891 	if (udma_mask)
892 		*udma_mask = (xfer_mask & ATA_MASK_UDMA) >> ATA_SHIFT_UDMA;
893 }
894 
895 static const struct ata_xfer_ent {
896 	int shift, bits;
897 	u8 base;
898 } ata_xfer_tbl[] = {
899 	{ ATA_SHIFT_PIO, ATA_NR_PIO_MODES, XFER_PIO_0 },
900 	{ ATA_SHIFT_MWDMA, ATA_NR_MWDMA_MODES, XFER_MW_DMA_0 },
901 	{ ATA_SHIFT_UDMA, ATA_NR_UDMA_MODES, XFER_UDMA_0 },
902 	{ -1, },
903 };
904 
905 /**
906  *	ata_xfer_mask2mode - Find matching XFER_* for the given xfer_mask
907  *	@xfer_mask: xfer_mask of interest
908  *
909  *	Return matching XFER_* value for @xfer_mask.  Only the highest
910  *	bit of @xfer_mask is considered.
911  *
912  *	LOCKING:
913  *	None.
914  *
915  *	RETURNS:
916  *	Matching XFER_* value, 0xff if no match found.
917  */
918 u8 ata_xfer_mask2mode(unsigned long xfer_mask)
919 {
920 	int highbit = fls(xfer_mask) - 1;
921 	const struct ata_xfer_ent *ent;
922 
923 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
924 		if (highbit >= ent->shift && highbit < ent->shift + ent->bits)
925 			return ent->base + highbit - ent->shift;
926 	return 0xff;
927 }
928 
929 /**
930  *	ata_xfer_mode2mask - Find matching xfer_mask for XFER_*
931  *	@xfer_mode: XFER_* of interest
932  *
933  *	Return matching xfer_mask for @xfer_mode.
934  *
935  *	LOCKING:
936  *	None.
937  *
938  *	RETURNS:
939  *	Matching xfer_mask, 0 if no match found.
940  */
941 unsigned long ata_xfer_mode2mask(u8 xfer_mode)
942 {
943 	const struct ata_xfer_ent *ent;
944 
945 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
946 		if (xfer_mode >= ent->base && xfer_mode < ent->base + ent->bits)
947 			return ((2 << (ent->shift + xfer_mode - ent->base)) - 1)
948 				& ~((1 << ent->shift) - 1);
949 	return 0;
950 }
951 
952 /**
953  *	ata_xfer_mode2shift - Find matching xfer_shift for XFER_*
954  *	@xfer_mode: XFER_* of interest
955  *
956  *	Return matching xfer_shift for @xfer_mode.
957  *
958  *	LOCKING:
959  *	None.
960  *
961  *	RETURNS:
962  *	Matching xfer_shift, -1 if no match found.
963  */
964 int ata_xfer_mode2shift(unsigned long xfer_mode)
965 {
966 	const struct ata_xfer_ent *ent;
967 
968 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
969 		if (xfer_mode >= ent->base && xfer_mode < ent->base + ent->bits)
970 			return ent->shift;
971 	return -1;
972 }
973 
974 /**
975  *	ata_mode_string - convert xfer_mask to string
976  *	@xfer_mask: mask of bits supported; only highest bit counts.
977  *
978  *	Determine string which represents the highest speed
979  *	(highest bit in @modemask).
980  *
981  *	LOCKING:
982  *	None.
983  *
984  *	RETURNS:
985  *	Constant C string representing highest speed listed in
986  *	@mode_mask, or the constant C string "<n/a>".
987  */
988 const char *ata_mode_string(unsigned long xfer_mask)
989 {
990 	static const char * const xfer_mode_str[] = {
991 		"PIO0",
992 		"PIO1",
993 		"PIO2",
994 		"PIO3",
995 		"PIO4",
996 		"PIO5",
997 		"PIO6",
998 		"MWDMA0",
999 		"MWDMA1",
1000 		"MWDMA2",
1001 		"MWDMA3",
1002 		"MWDMA4",
1003 		"UDMA/16",
1004 		"UDMA/25",
1005 		"UDMA/33",
1006 		"UDMA/44",
1007 		"UDMA/66",
1008 		"UDMA/100",
1009 		"UDMA/133",
1010 		"UDMA7",
1011 	};
1012 	int highbit;
1013 
1014 	highbit = fls(xfer_mask) - 1;
1015 	if (highbit >= 0 && highbit < ARRAY_SIZE(xfer_mode_str))
1016 		return xfer_mode_str[highbit];
1017 	return "<n/a>";
1018 }
1019 
1020 const char *sata_spd_string(unsigned int spd)
1021 {
1022 	static const char * const spd_str[] = {
1023 		"1.5 Gbps",
1024 		"3.0 Gbps",
1025 		"6.0 Gbps",
1026 	};
1027 
1028 	if (spd == 0 || (spd - 1) >= ARRAY_SIZE(spd_str))
1029 		return "<unknown>";
1030 	return spd_str[spd - 1];
1031 }
1032 
1033 /**
1034  *	ata_dev_classify - determine device type based on ATA-spec signature
1035  *	@tf: ATA taskfile register set for device to be identified
1036  *
1037  *	Determine from taskfile register contents whether a device is
1038  *	ATA or ATAPI, as per "Signature and persistence" section
1039  *	of ATA/PI spec (volume 1, sect 5.14).
1040  *
1041  *	LOCKING:
1042  *	None.
1043  *
1044  *	RETURNS:
1045  *	Device type, %ATA_DEV_ATA, %ATA_DEV_ATAPI, %ATA_DEV_PMP or
1046  *	%ATA_DEV_UNKNOWN the event of failure.
1047  */
1048 unsigned int ata_dev_classify(const struct ata_taskfile *tf)
1049 {
1050 	/* Apple's open source Darwin code hints that some devices only
1051 	 * put a proper signature into the LBA mid/high registers,
1052 	 * So, we only check those.  It's sufficient for uniqueness.
1053 	 *
1054 	 * ATA/ATAPI-7 (d1532v1r1: Feb. 19, 2003) specified separate
1055 	 * signatures for ATA and ATAPI devices attached on SerialATA,
1056 	 * 0x3c/0xc3 and 0x69/0x96 respectively.  However, SerialATA
1057 	 * spec has never mentioned about using different signatures
1058 	 * for ATA/ATAPI devices.  Then, Serial ATA II: Port
1059 	 * Multiplier specification began to use 0x69/0x96 to identify
1060 	 * port multpliers and 0x3c/0xc3 to identify SEMB device.
1061 	 * ATA/ATAPI-7 dropped descriptions about 0x3c/0xc3 and
1062 	 * 0x69/0x96 shortly and described them as reserved for
1063 	 * SerialATA.
1064 	 *
1065 	 * We follow the current spec and consider that 0x69/0x96
1066 	 * identifies a port multiplier and 0x3c/0xc3 a SEMB device.
1067 	 * Unfortunately, WDC WD1600JS-62MHB5 (a hard drive) reports
1068 	 * SEMB signature.  This is worked around in
1069 	 * ata_dev_read_id().
1070 	 */
1071 	if ((tf->lbam == 0) && (tf->lbah == 0)) {
1072 		DPRINTK("found ATA device by sig\n");
1073 		return ATA_DEV_ATA;
1074 	}
1075 
1076 	if ((tf->lbam == 0x14) && (tf->lbah == 0xeb)) {
1077 		DPRINTK("found ATAPI device by sig\n");
1078 		return ATA_DEV_ATAPI;
1079 	}
1080 
1081 	if ((tf->lbam == 0x69) && (tf->lbah == 0x96)) {
1082 		DPRINTK("found PMP device by sig\n");
1083 		return ATA_DEV_PMP;
1084 	}
1085 
1086 	if ((tf->lbam == 0x3c) && (tf->lbah == 0xc3)) {
1087 		DPRINTK("found SEMB device by sig (could be ATA device)\n");
1088 		return ATA_DEV_SEMB;
1089 	}
1090 
1091 	DPRINTK("unknown device\n");
1092 	return ATA_DEV_UNKNOWN;
1093 }
1094 
1095 /**
1096  *	ata_id_string - Convert IDENTIFY DEVICE page into string
1097  *	@id: IDENTIFY DEVICE results we will examine
1098  *	@s: string into which data is output
1099  *	@ofs: offset into identify device page
1100  *	@len: length of string to return. must be an even number.
1101  *
1102  *	The strings in the IDENTIFY DEVICE page are broken up into
1103  *	16-bit chunks.  Run through the string, and output each
1104  *	8-bit chunk linearly, regardless of platform.
1105  *
1106  *	LOCKING:
1107  *	caller.
1108  */
1109 
1110 void ata_id_string(const u16 *id, unsigned char *s,
1111 		   unsigned int ofs, unsigned int len)
1112 {
1113 	unsigned int c;
1114 
1115 	BUG_ON(len & 1);
1116 
1117 	while (len > 0) {
1118 		c = id[ofs] >> 8;
1119 		*s = c;
1120 		s++;
1121 
1122 		c = id[ofs] & 0xff;
1123 		*s = c;
1124 		s++;
1125 
1126 		ofs++;
1127 		len -= 2;
1128 	}
1129 }
1130 
1131 /**
1132  *	ata_id_c_string - Convert IDENTIFY DEVICE page into C string
1133  *	@id: IDENTIFY DEVICE results we will examine
1134  *	@s: string into which data is output
1135  *	@ofs: offset into identify device page
1136  *	@len: length of string to return. must be an odd number.
1137  *
1138  *	This function is identical to ata_id_string except that it
1139  *	trims trailing spaces and terminates the resulting string with
1140  *	null.  @len must be actual maximum length (even number) + 1.
1141  *
1142  *	LOCKING:
1143  *	caller.
1144  */
1145 void ata_id_c_string(const u16 *id, unsigned char *s,
1146 		     unsigned int ofs, unsigned int len)
1147 {
1148 	unsigned char *p;
1149 
1150 	ata_id_string(id, s, ofs, len - 1);
1151 
1152 	p = s + strnlen(s, len - 1);
1153 	while (p > s && p[-1] == ' ')
1154 		p--;
1155 	*p = '\0';
1156 }
1157 
1158 static u64 ata_id_n_sectors(const u16 *id)
1159 {
1160 	if (ata_id_has_lba(id)) {
1161 		if (ata_id_has_lba48(id))
1162 			return ata_id_u64(id, ATA_ID_LBA_CAPACITY_2);
1163 		else
1164 			return ata_id_u32(id, ATA_ID_LBA_CAPACITY);
1165 	} else {
1166 		if (ata_id_current_chs_valid(id))
1167 			return id[ATA_ID_CUR_CYLS] * id[ATA_ID_CUR_HEADS] *
1168 			       id[ATA_ID_CUR_SECTORS];
1169 		else
1170 			return id[ATA_ID_CYLS] * id[ATA_ID_HEADS] *
1171 			       id[ATA_ID_SECTORS];
1172 	}
1173 }
1174 
1175 u64 ata_tf_to_lba48(const struct ata_taskfile *tf)
1176 {
1177 	u64 sectors = 0;
1178 
1179 	sectors |= ((u64)(tf->hob_lbah & 0xff)) << 40;
1180 	sectors |= ((u64)(tf->hob_lbam & 0xff)) << 32;
1181 	sectors |= ((u64)(tf->hob_lbal & 0xff)) << 24;
1182 	sectors |= (tf->lbah & 0xff) << 16;
1183 	sectors |= (tf->lbam & 0xff) << 8;
1184 	sectors |= (tf->lbal & 0xff);
1185 
1186 	return sectors;
1187 }
1188 
1189 u64 ata_tf_to_lba(const struct ata_taskfile *tf)
1190 {
1191 	u64 sectors = 0;
1192 
1193 	sectors |= (tf->device & 0x0f) << 24;
1194 	sectors |= (tf->lbah & 0xff) << 16;
1195 	sectors |= (tf->lbam & 0xff) << 8;
1196 	sectors |= (tf->lbal & 0xff);
1197 
1198 	return sectors;
1199 }
1200 
1201 /**
1202  *	ata_read_native_max_address - Read native max address
1203  *	@dev: target device
1204  *	@max_sectors: out parameter for the result native max address
1205  *
1206  *	Perform an LBA48 or LBA28 native size query upon the device in
1207  *	question.
1208  *
1209  *	RETURNS:
1210  *	0 on success, -EACCES if command is aborted by the drive.
1211  *	-EIO on other errors.
1212  */
1213 static int ata_read_native_max_address(struct ata_device *dev, u64 *max_sectors)
1214 {
1215 	unsigned int err_mask;
1216 	struct ata_taskfile tf;
1217 	int lba48 = ata_id_has_lba48(dev->id);
1218 
1219 	ata_tf_init(dev, &tf);
1220 
1221 	/* always clear all address registers */
1222 	tf.flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
1223 
1224 	if (lba48) {
1225 		tf.command = ATA_CMD_READ_NATIVE_MAX_EXT;
1226 		tf.flags |= ATA_TFLAG_LBA48;
1227 	} else
1228 		tf.command = ATA_CMD_READ_NATIVE_MAX;
1229 
1230 	tf.protocol |= ATA_PROT_NODATA;
1231 	tf.device |= ATA_LBA;
1232 
1233 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
1234 	if (err_mask) {
1235 		ata_dev_warn(dev,
1236 			     "failed to read native max address (err_mask=0x%x)\n",
1237 			     err_mask);
1238 		if (err_mask == AC_ERR_DEV && (tf.feature & ATA_ABORTED))
1239 			return -EACCES;
1240 		return -EIO;
1241 	}
1242 
1243 	if (lba48)
1244 		*max_sectors = ata_tf_to_lba48(&tf) + 1;
1245 	else
1246 		*max_sectors = ata_tf_to_lba(&tf) + 1;
1247 	if (dev->horkage & ATA_HORKAGE_HPA_SIZE)
1248 		(*max_sectors)--;
1249 	return 0;
1250 }
1251 
1252 /**
1253  *	ata_set_max_sectors - Set max sectors
1254  *	@dev: target device
1255  *	@new_sectors: new max sectors value to set for the device
1256  *
1257  *	Set max sectors of @dev to @new_sectors.
1258  *
1259  *	RETURNS:
1260  *	0 on success, -EACCES if command is aborted or denied (due to
1261  *	previous non-volatile SET_MAX) by the drive.  -EIO on other
1262  *	errors.
1263  */
1264 static int ata_set_max_sectors(struct ata_device *dev, u64 new_sectors)
1265 {
1266 	unsigned int err_mask;
1267 	struct ata_taskfile tf;
1268 	int lba48 = ata_id_has_lba48(dev->id);
1269 
1270 	new_sectors--;
1271 
1272 	ata_tf_init(dev, &tf);
1273 
1274 	tf.flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
1275 
1276 	if (lba48) {
1277 		tf.command = ATA_CMD_SET_MAX_EXT;
1278 		tf.flags |= ATA_TFLAG_LBA48;
1279 
1280 		tf.hob_lbal = (new_sectors >> 24) & 0xff;
1281 		tf.hob_lbam = (new_sectors >> 32) & 0xff;
1282 		tf.hob_lbah = (new_sectors >> 40) & 0xff;
1283 	} else {
1284 		tf.command = ATA_CMD_SET_MAX;
1285 
1286 		tf.device |= (new_sectors >> 24) & 0xf;
1287 	}
1288 
1289 	tf.protocol |= ATA_PROT_NODATA;
1290 	tf.device |= ATA_LBA;
1291 
1292 	tf.lbal = (new_sectors >> 0) & 0xff;
1293 	tf.lbam = (new_sectors >> 8) & 0xff;
1294 	tf.lbah = (new_sectors >> 16) & 0xff;
1295 
1296 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
1297 	if (err_mask) {
1298 		ata_dev_warn(dev,
1299 			     "failed to set max address (err_mask=0x%x)\n",
1300 			     err_mask);
1301 		if (err_mask == AC_ERR_DEV &&
1302 		    (tf.feature & (ATA_ABORTED | ATA_IDNF)))
1303 			return -EACCES;
1304 		return -EIO;
1305 	}
1306 
1307 	return 0;
1308 }
1309 
1310 /**
1311  *	ata_hpa_resize		-	Resize a device with an HPA set
1312  *	@dev: Device to resize
1313  *
1314  *	Read the size of an LBA28 or LBA48 disk with HPA features and resize
1315  *	it if required to the full size of the media. The caller must check
1316  *	the drive has the HPA feature set enabled.
1317  *
1318  *	RETURNS:
1319  *	0 on success, -errno on failure.
1320  */
1321 static int ata_hpa_resize(struct ata_device *dev)
1322 {
1323 	struct ata_eh_context *ehc = &dev->link->eh_context;
1324 	int print_info = ehc->i.flags & ATA_EHI_PRINTINFO;
1325 	bool unlock_hpa = ata_ignore_hpa || dev->flags & ATA_DFLAG_UNLOCK_HPA;
1326 	u64 sectors = ata_id_n_sectors(dev->id);
1327 	u64 native_sectors;
1328 	int rc;
1329 
1330 	/* do we need to do it? */
1331 	if (dev->class != ATA_DEV_ATA ||
1332 	    !ata_id_has_lba(dev->id) || !ata_id_hpa_enabled(dev->id) ||
1333 	    (dev->horkage & ATA_HORKAGE_BROKEN_HPA))
1334 		return 0;
1335 
1336 	/* read native max address */
1337 	rc = ata_read_native_max_address(dev, &native_sectors);
1338 	if (rc) {
1339 		/* If device aborted the command or HPA isn't going to
1340 		 * be unlocked, skip HPA resizing.
1341 		 */
1342 		if (rc == -EACCES || !unlock_hpa) {
1343 			ata_dev_warn(dev,
1344 				     "HPA support seems broken, skipping HPA handling\n");
1345 			dev->horkage |= ATA_HORKAGE_BROKEN_HPA;
1346 
1347 			/* we can continue if device aborted the command */
1348 			if (rc == -EACCES)
1349 				rc = 0;
1350 		}
1351 
1352 		return rc;
1353 	}
1354 	dev->n_native_sectors = native_sectors;
1355 
1356 	/* nothing to do? */
1357 	if (native_sectors <= sectors || !unlock_hpa) {
1358 		if (!print_info || native_sectors == sectors)
1359 			return 0;
1360 
1361 		if (native_sectors > sectors)
1362 			ata_dev_info(dev,
1363 				"HPA detected: current %llu, native %llu\n",
1364 				(unsigned long long)sectors,
1365 				(unsigned long long)native_sectors);
1366 		else if (native_sectors < sectors)
1367 			ata_dev_warn(dev,
1368 				"native sectors (%llu) is smaller than sectors (%llu)\n",
1369 				(unsigned long long)native_sectors,
1370 				(unsigned long long)sectors);
1371 		return 0;
1372 	}
1373 
1374 	/* let's unlock HPA */
1375 	rc = ata_set_max_sectors(dev, native_sectors);
1376 	if (rc == -EACCES) {
1377 		/* if device aborted the command, skip HPA resizing */
1378 		ata_dev_warn(dev,
1379 			     "device aborted resize (%llu -> %llu), skipping HPA handling\n",
1380 			     (unsigned long long)sectors,
1381 			     (unsigned long long)native_sectors);
1382 		dev->horkage |= ATA_HORKAGE_BROKEN_HPA;
1383 		return 0;
1384 	} else if (rc)
1385 		return rc;
1386 
1387 	/* re-read IDENTIFY data */
1388 	rc = ata_dev_reread_id(dev, 0);
1389 	if (rc) {
1390 		ata_dev_err(dev,
1391 			    "failed to re-read IDENTIFY data after HPA resizing\n");
1392 		return rc;
1393 	}
1394 
1395 	if (print_info) {
1396 		u64 new_sectors = ata_id_n_sectors(dev->id);
1397 		ata_dev_info(dev,
1398 			"HPA unlocked: %llu -> %llu, native %llu\n",
1399 			(unsigned long long)sectors,
1400 			(unsigned long long)new_sectors,
1401 			(unsigned long long)native_sectors);
1402 	}
1403 
1404 	return 0;
1405 }
1406 
1407 /**
1408  *	ata_dump_id - IDENTIFY DEVICE info debugging output
1409  *	@id: IDENTIFY DEVICE page to dump
1410  *
1411  *	Dump selected 16-bit words from the given IDENTIFY DEVICE
1412  *	page.
1413  *
1414  *	LOCKING:
1415  *	caller.
1416  */
1417 
1418 static inline void ata_dump_id(const u16 *id)
1419 {
1420 	DPRINTK("49==0x%04x  "
1421 		"53==0x%04x  "
1422 		"63==0x%04x  "
1423 		"64==0x%04x  "
1424 		"75==0x%04x  \n",
1425 		id[49],
1426 		id[53],
1427 		id[63],
1428 		id[64],
1429 		id[75]);
1430 	DPRINTK("80==0x%04x  "
1431 		"81==0x%04x  "
1432 		"82==0x%04x  "
1433 		"83==0x%04x  "
1434 		"84==0x%04x  \n",
1435 		id[80],
1436 		id[81],
1437 		id[82],
1438 		id[83],
1439 		id[84]);
1440 	DPRINTK("88==0x%04x  "
1441 		"93==0x%04x\n",
1442 		id[88],
1443 		id[93]);
1444 }
1445 
1446 /**
1447  *	ata_id_xfermask - Compute xfermask from the given IDENTIFY data
1448  *	@id: IDENTIFY data to compute xfer mask from
1449  *
1450  *	Compute the xfermask for this device. This is not as trivial
1451  *	as it seems if we must consider early devices correctly.
1452  *
1453  *	FIXME: pre IDE drive timing (do we care ?).
1454  *
1455  *	LOCKING:
1456  *	None.
1457  *
1458  *	RETURNS:
1459  *	Computed xfermask
1460  */
1461 unsigned long ata_id_xfermask(const u16 *id)
1462 {
1463 	unsigned long pio_mask, mwdma_mask, udma_mask;
1464 
1465 	/* Usual case. Word 53 indicates word 64 is valid */
1466 	if (id[ATA_ID_FIELD_VALID] & (1 << 1)) {
1467 		pio_mask = id[ATA_ID_PIO_MODES] & 0x03;
1468 		pio_mask <<= 3;
1469 		pio_mask |= 0x7;
1470 	} else {
1471 		/* If word 64 isn't valid then Word 51 high byte holds
1472 		 * the PIO timing number for the maximum. Turn it into
1473 		 * a mask.
1474 		 */
1475 		u8 mode = (id[ATA_ID_OLD_PIO_MODES] >> 8) & 0xFF;
1476 		if (mode < 5)	/* Valid PIO range */
1477 			pio_mask = (2 << mode) - 1;
1478 		else
1479 			pio_mask = 1;
1480 
1481 		/* But wait.. there's more. Design your standards by
1482 		 * committee and you too can get a free iordy field to
1483 		 * process. However its the speeds not the modes that
1484 		 * are supported... Note drivers using the timing API
1485 		 * will get this right anyway
1486 		 */
1487 	}
1488 
1489 	mwdma_mask = id[ATA_ID_MWDMA_MODES] & 0x07;
1490 
1491 	if (ata_id_is_cfa(id)) {
1492 		/*
1493 		 *	Process compact flash extended modes
1494 		 */
1495 		int pio = (id[ATA_ID_CFA_MODES] >> 0) & 0x7;
1496 		int dma = (id[ATA_ID_CFA_MODES] >> 3) & 0x7;
1497 
1498 		if (pio)
1499 			pio_mask |= (1 << 5);
1500 		if (pio > 1)
1501 			pio_mask |= (1 << 6);
1502 		if (dma)
1503 			mwdma_mask |= (1 << 3);
1504 		if (dma > 1)
1505 			mwdma_mask |= (1 << 4);
1506 	}
1507 
1508 	udma_mask = 0;
1509 	if (id[ATA_ID_FIELD_VALID] & (1 << 2))
1510 		udma_mask = id[ATA_ID_UDMA_MODES] & 0xff;
1511 
1512 	return ata_pack_xfermask(pio_mask, mwdma_mask, udma_mask);
1513 }
1514 
1515 static void ata_qc_complete_internal(struct ata_queued_cmd *qc)
1516 {
1517 	struct completion *waiting = qc->private_data;
1518 
1519 	complete(waiting);
1520 }
1521 
1522 /**
1523  *	ata_exec_internal_sg - execute libata internal command
1524  *	@dev: Device to which the command is sent
1525  *	@tf: Taskfile registers for the command and the result
1526  *	@cdb: CDB for packet command
1527  *	@dma_dir: Data transfer direction of the command
1528  *	@sgl: sg list for the data buffer of the command
1529  *	@n_elem: Number of sg entries
1530  *	@timeout: Timeout in msecs (0 for default)
1531  *
1532  *	Executes libata internal command with timeout.  @tf contains
1533  *	command on entry and result on return.  Timeout and error
1534  *	conditions are reported via return value.  No recovery action
1535  *	is taken after a command times out.  It's caller's duty to
1536  *	clean up after timeout.
1537  *
1538  *	LOCKING:
1539  *	None.  Should be called with kernel context, might sleep.
1540  *
1541  *	RETURNS:
1542  *	Zero on success, AC_ERR_* mask on failure
1543  */
1544 unsigned ata_exec_internal_sg(struct ata_device *dev,
1545 			      struct ata_taskfile *tf, const u8 *cdb,
1546 			      int dma_dir, struct scatterlist *sgl,
1547 			      unsigned int n_elem, unsigned long timeout)
1548 {
1549 	struct ata_link *link = dev->link;
1550 	struct ata_port *ap = link->ap;
1551 	u8 command = tf->command;
1552 	int auto_timeout = 0;
1553 	struct ata_queued_cmd *qc;
1554 	unsigned int tag, preempted_tag;
1555 	u32 preempted_sactive, preempted_qc_active;
1556 	int preempted_nr_active_links;
1557 	DECLARE_COMPLETION_ONSTACK(wait);
1558 	unsigned long flags;
1559 	unsigned int err_mask;
1560 	int rc;
1561 
1562 	spin_lock_irqsave(ap->lock, flags);
1563 
1564 	/* no internal command while frozen */
1565 	if (ap->pflags & ATA_PFLAG_FROZEN) {
1566 		spin_unlock_irqrestore(ap->lock, flags);
1567 		return AC_ERR_SYSTEM;
1568 	}
1569 
1570 	/* initialize internal qc */
1571 
1572 	/* XXX: Tag 0 is used for drivers with legacy EH as some
1573 	 * drivers choke if any other tag is given.  This breaks
1574 	 * ata_tag_internal() test for those drivers.  Don't use new
1575 	 * EH stuff without converting to it.
1576 	 */
1577 	if (ap->ops->error_handler)
1578 		tag = ATA_TAG_INTERNAL;
1579 	else
1580 		tag = 0;
1581 
1582 	if (test_and_set_bit(tag, &ap->qc_allocated))
1583 		BUG();
1584 	qc = __ata_qc_from_tag(ap, tag);
1585 
1586 	qc->tag = tag;
1587 	qc->scsicmd = NULL;
1588 	qc->ap = ap;
1589 	qc->dev = dev;
1590 	ata_qc_reinit(qc);
1591 
1592 	preempted_tag = link->active_tag;
1593 	preempted_sactive = link->sactive;
1594 	preempted_qc_active = ap->qc_active;
1595 	preempted_nr_active_links = ap->nr_active_links;
1596 	link->active_tag = ATA_TAG_POISON;
1597 	link->sactive = 0;
1598 	ap->qc_active = 0;
1599 	ap->nr_active_links = 0;
1600 
1601 	/* prepare & issue qc */
1602 	qc->tf = *tf;
1603 	if (cdb)
1604 		memcpy(qc->cdb, cdb, ATAPI_CDB_LEN);
1605 
1606 	/* some SATA bridges need us to indicate data xfer direction */
1607 	if (tf->protocol == ATAPI_PROT_DMA && (dev->flags & ATA_DFLAG_DMADIR) &&
1608 	    dma_dir == DMA_FROM_DEVICE)
1609 		qc->tf.feature |= ATAPI_DMADIR;
1610 
1611 	qc->flags |= ATA_QCFLAG_RESULT_TF;
1612 	qc->dma_dir = dma_dir;
1613 	if (dma_dir != DMA_NONE) {
1614 		unsigned int i, buflen = 0;
1615 		struct scatterlist *sg;
1616 
1617 		for_each_sg(sgl, sg, n_elem, i)
1618 			buflen += sg->length;
1619 
1620 		ata_sg_init(qc, sgl, n_elem);
1621 		qc->nbytes = buflen;
1622 	}
1623 
1624 	qc->private_data = &wait;
1625 	qc->complete_fn = ata_qc_complete_internal;
1626 
1627 	ata_qc_issue(qc);
1628 
1629 	spin_unlock_irqrestore(ap->lock, flags);
1630 
1631 	if (!timeout) {
1632 		if (ata_probe_timeout)
1633 			timeout = ata_probe_timeout * 1000;
1634 		else {
1635 			timeout = ata_internal_cmd_timeout(dev, command);
1636 			auto_timeout = 1;
1637 		}
1638 	}
1639 
1640 	if (ap->ops->error_handler)
1641 		ata_eh_release(ap);
1642 
1643 	rc = wait_for_completion_timeout(&wait, msecs_to_jiffies(timeout));
1644 
1645 	if (ap->ops->error_handler)
1646 		ata_eh_acquire(ap);
1647 
1648 	ata_sff_flush_pio_task(ap);
1649 
1650 	if (!rc) {
1651 		spin_lock_irqsave(ap->lock, flags);
1652 
1653 		/* We're racing with irq here.  If we lose, the
1654 		 * following test prevents us from completing the qc
1655 		 * twice.  If we win, the port is frozen and will be
1656 		 * cleaned up by ->post_internal_cmd().
1657 		 */
1658 		if (qc->flags & ATA_QCFLAG_ACTIVE) {
1659 			qc->err_mask |= AC_ERR_TIMEOUT;
1660 
1661 			if (ap->ops->error_handler)
1662 				ata_port_freeze(ap);
1663 			else
1664 				ata_qc_complete(qc);
1665 
1666 			if (ata_msg_warn(ap))
1667 				ata_dev_warn(dev, "qc timeout (cmd 0x%x)\n",
1668 					     command);
1669 		}
1670 
1671 		spin_unlock_irqrestore(ap->lock, flags);
1672 	}
1673 
1674 	/* do post_internal_cmd */
1675 	if (ap->ops->post_internal_cmd)
1676 		ap->ops->post_internal_cmd(qc);
1677 
1678 	/* perform minimal error analysis */
1679 	if (qc->flags & ATA_QCFLAG_FAILED) {
1680 		if (qc->result_tf.command & (ATA_ERR | ATA_DF))
1681 			qc->err_mask |= AC_ERR_DEV;
1682 
1683 		if (!qc->err_mask)
1684 			qc->err_mask |= AC_ERR_OTHER;
1685 
1686 		if (qc->err_mask & ~AC_ERR_OTHER)
1687 			qc->err_mask &= ~AC_ERR_OTHER;
1688 	}
1689 
1690 	/* finish up */
1691 	spin_lock_irqsave(ap->lock, flags);
1692 
1693 	*tf = qc->result_tf;
1694 	err_mask = qc->err_mask;
1695 
1696 	ata_qc_free(qc);
1697 	link->active_tag = preempted_tag;
1698 	link->sactive = preempted_sactive;
1699 	ap->qc_active = preempted_qc_active;
1700 	ap->nr_active_links = preempted_nr_active_links;
1701 
1702 	spin_unlock_irqrestore(ap->lock, flags);
1703 
1704 	if ((err_mask & AC_ERR_TIMEOUT) && auto_timeout)
1705 		ata_internal_cmd_timed_out(dev, command);
1706 
1707 	return err_mask;
1708 }
1709 
1710 /**
1711  *	ata_exec_internal - execute libata internal command
1712  *	@dev: Device to which the command is sent
1713  *	@tf: Taskfile registers for the command and the result
1714  *	@cdb: CDB for packet command
1715  *	@dma_dir: Data transfer direction of the command
1716  *	@buf: Data buffer of the command
1717  *	@buflen: Length of data buffer
1718  *	@timeout: Timeout in msecs (0 for default)
1719  *
1720  *	Wrapper around ata_exec_internal_sg() which takes simple
1721  *	buffer instead of sg list.
1722  *
1723  *	LOCKING:
1724  *	None.  Should be called with kernel context, might sleep.
1725  *
1726  *	RETURNS:
1727  *	Zero on success, AC_ERR_* mask on failure
1728  */
1729 unsigned ata_exec_internal(struct ata_device *dev,
1730 			   struct ata_taskfile *tf, const u8 *cdb,
1731 			   int dma_dir, void *buf, unsigned int buflen,
1732 			   unsigned long timeout)
1733 {
1734 	struct scatterlist *psg = NULL, sg;
1735 	unsigned int n_elem = 0;
1736 
1737 	if (dma_dir != DMA_NONE) {
1738 		WARN_ON(!buf);
1739 		sg_init_one(&sg, buf, buflen);
1740 		psg = &sg;
1741 		n_elem++;
1742 	}
1743 
1744 	return ata_exec_internal_sg(dev, tf, cdb, dma_dir, psg, n_elem,
1745 				    timeout);
1746 }
1747 
1748 /**
1749  *	ata_do_simple_cmd - execute simple internal command
1750  *	@dev: Device to which the command is sent
1751  *	@cmd: Opcode to execute
1752  *
1753  *	Execute a 'simple' command, that only consists of the opcode
1754  *	'cmd' itself, without filling any other registers
1755  *
1756  *	LOCKING:
1757  *	Kernel thread context (may sleep).
1758  *
1759  *	RETURNS:
1760  *	Zero on success, AC_ERR_* mask on failure
1761  */
1762 unsigned int ata_do_simple_cmd(struct ata_device *dev, u8 cmd)
1763 {
1764 	struct ata_taskfile tf;
1765 
1766 	ata_tf_init(dev, &tf);
1767 
1768 	tf.command = cmd;
1769 	tf.flags |= ATA_TFLAG_DEVICE;
1770 	tf.protocol = ATA_PROT_NODATA;
1771 
1772 	return ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
1773 }
1774 
1775 /**
1776  *	ata_pio_need_iordy	-	check if iordy needed
1777  *	@adev: ATA device
1778  *
1779  *	Check if the current speed of the device requires IORDY. Used
1780  *	by various controllers for chip configuration.
1781  */
1782 unsigned int ata_pio_need_iordy(const struct ata_device *adev)
1783 {
1784 	/* Don't set IORDY if we're preparing for reset.  IORDY may
1785 	 * lead to controller lock up on certain controllers if the
1786 	 * port is not occupied.  See bko#11703 for details.
1787 	 */
1788 	if (adev->link->ap->pflags & ATA_PFLAG_RESETTING)
1789 		return 0;
1790 	/* Controller doesn't support IORDY.  Probably a pointless
1791 	 * check as the caller should know this.
1792 	 */
1793 	if (adev->link->ap->flags & ATA_FLAG_NO_IORDY)
1794 		return 0;
1795 	/* CF spec. r4.1 Table 22 says no iordy on PIO5 and PIO6.  */
1796 	if (ata_id_is_cfa(adev->id)
1797 	    && (adev->pio_mode == XFER_PIO_5 || adev->pio_mode == XFER_PIO_6))
1798 		return 0;
1799 	/* PIO3 and higher it is mandatory */
1800 	if (adev->pio_mode > XFER_PIO_2)
1801 		return 1;
1802 	/* We turn it on when possible */
1803 	if (ata_id_has_iordy(adev->id))
1804 		return 1;
1805 	return 0;
1806 }
1807 
1808 /**
1809  *	ata_pio_mask_no_iordy	-	Return the non IORDY mask
1810  *	@adev: ATA device
1811  *
1812  *	Compute the highest mode possible if we are not using iordy. Return
1813  *	-1 if no iordy mode is available.
1814  */
1815 static u32 ata_pio_mask_no_iordy(const struct ata_device *adev)
1816 {
1817 	/* If we have no drive specific rule, then PIO 2 is non IORDY */
1818 	if (adev->id[ATA_ID_FIELD_VALID] & 2) {	/* EIDE */
1819 		u16 pio = adev->id[ATA_ID_EIDE_PIO];
1820 		/* Is the speed faster than the drive allows non IORDY ? */
1821 		if (pio) {
1822 			/* This is cycle times not frequency - watch the logic! */
1823 			if (pio > 240)	/* PIO2 is 240nS per cycle */
1824 				return 3 << ATA_SHIFT_PIO;
1825 			return 7 << ATA_SHIFT_PIO;
1826 		}
1827 	}
1828 	return 3 << ATA_SHIFT_PIO;
1829 }
1830 
1831 /**
1832  *	ata_do_dev_read_id		-	default ID read method
1833  *	@dev: device
1834  *	@tf: proposed taskfile
1835  *	@id: data buffer
1836  *
1837  *	Issue the identify taskfile and hand back the buffer containing
1838  *	identify data. For some RAID controllers and for pre ATA devices
1839  *	this function is wrapped or replaced by the driver
1840  */
1841 unsigned int ata_do_dev_read_id(struct ata_device *dev,
1842 					struct ata_taskfile *tf, u16 *id)
1843 {
1844 	return ata_exec_internal(dev, tf, NULL, DMA_FROM_DEVICE,
1845 				     id, sizeof(id[0]) * ATA_ID_WORDS, 0);
1846 }
1847 
1848 /**
1849  *	ata_dev_read_id - Read ID data from the specified device
1850  *	@dev: target device
1851  *	@p_class: pointer to class of the target device (may be changed)
1852  *	@flags: ATA_READID_* flags
1853  *	@id: buffer to read IDENTIFY data into
1854  *
1855  *	Read ID data from the specified device.  ATA_CMD_ID_ATA is
1856  *	performed on ATA devices and ATA_CMD_ID_ATAPI on ATAPI
1857  *	devices.  This function also issues ATA_CMD_INIT_DEV_PARAMS
1858  *	for pre-ATA4 drives.
1859  *
1860  *	FIXME: ATA_CMD_ID_ATA is optional for early drives and right
1861  *	now we abort if we hit that case.
1862  *
1863  *	LOCKING:
1864  *	Kernel thread context (may sleep)
1865  *
1866  *	RETURNS:
1867  *	0 on success, -errno otherwise.
1868  */
1869 int ata_dev_read_id(struct ata_device *dev, unsigned int *p_class,
1870 		    unsigned int flags, u16 *id)
1871 {
1872 	struct ata_port *ap = dev->link->ap;
1873 	unsigned int class = *p_class;
1874 	struct ata_taskfile tf;
1875 	unsigned int err_mask = 0;
1876 	const char *reason;
1877 	bool is_semb = class == ATA_DEV_SEMB;
1878 	int may_fallback = 1, tried_spinup = 0;
1879 	int rc;
1880 
1881 	if (ata_msg_ctl(ap))
1882 		ata_dev_dbg(dev, "%s: ENTER\n", __func__);
1883 
1884 retry:
1885 	ata_tf_init(dev, &tf);
1886 
1887 	switch (class) {
1888 	case ATA_DEV_SEMB:
1889 		class = ATA_DEV_ATA;	/* some hard drives report SEMB sig */
1890 	case ATA_DEV_ATA:
1891 		tf.command = ATA_CMD_ID_ATA;
1892 		break;
1893 	case ATA_DEV_ATAPI:
1894 		tf.command = ATA_CMD_ID_ATAPI;
1895 		break;
1896 	default:
1897 		rc = -ENODEV;
1898 		reason = "unsupported class";
1899 		goto err_out;
1900 	}
1901 
1902 	tf.protocol = ATA_PROT_PIO;
1903 
1904 	/* Some devices choke if TF registers contain garbage.  Make
1905 	 * sure those are properly initialized.
1906 	 */
1907 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1908 
1909 	/* Device presence detection is unreliable on some
1910 	 * controllers.  Always poll IDENTIFY if available.
1911 	 */
1912 	tf.flags |= ATA_TFLAG_POLLING;
1913 
1914 	if (ap->ops->read_id)
1915 		err_mask = ap->ops->read_id(dev, &tf, id);
1916 	else
1917 		err_mask = ata_do_dev_read_id(dev, &tf, id);
1918 
1919 	if (err_mask) {
1920 		if (err_mask & AC_ERR_NODEV_HINT) {
1921 			ata_dev_dbg(dev, "NODEV after polling detection\n");
1922 			return -ENOENT;
1923 		}
1924 
1925 		if (is_semb) {
1926 			ata_dev_info(dev,
1927 		     "IDENTIFY failed on device w/ SEMB sig, disabled\n");
1928 			/* SEMB is not supported yet */
1929 			*p_class = ATA_DEV_SEMB_UNSUP;
1930 			return 0;
1931 		}
1932 
1933 		if ((err_mask == AC_ERR_DEV) && (tf.feature & ATA_ABORTED)) {
1934 			/* Device or controller might have reported
1935 			 * the wrong device class.  Give a shot at the
1936 			 * other IDENTIFY if the current one is
1937 			 * aborted by the device.
1938 			 */
1939 			if (may_fallback) {
1940 				may_fallback = 0;
1941 
1942 				if (class == ATA_DEV_ATA)
1943 					class = ATA_DEV_ATAPI;
1944 				else
1945 					class = ATA_DEV_ATA;
1946 				goto retry;
1947 			}
1948 
1949 			/* Control reaches here iff the device aborted
1950 			 * both flavors of IDENTIFYs which happens
1951 			 * sometimes with phantom devices.
1952 			 */
1953 			ata_dev_dbg(dev,
1954 				    "both IDENTIFYs aborted, assuming NODEV\n");
1955 			return -ENOENT;
1956 		}
1957 
1958 		rc = -EIO;
1959 		reason = "I/O error";
1960 		goto err_out;
1961 	}
1962 
1963 	if (dev->horkage & ATA_HORKAGE_DUMP_ID) {
1964 		ata_dev_dbg(dev, "dumping IDENTIFY data, "
1965 			    "class=%d may_fallback=%d tried_spinup=%d\n",
1966 			    class, may_fallback, tried_spinup);
1967 		print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET,
1968 			       16, 2, id, ATA_ID_WORDS * sizeof(*id), true);
1969 	}
1970 
1971 	/* Falling back doesn't make sense if ID data was read
1972 	 * successfully at least once.
1973 	 */
1974 	may_fallback = 0;
1975 
1976 	swap_buf_le16(id, ATA_ID_WORDS);
1977 
1978 	/* sanity check */
1979 	rc = -EINVAL;
1980 	reason = "device reports invalid type";
1981 
1982 	if (class == ATA_DEV_ATA) {
1983 		if (!ata_id_is_ata(id) && !ata_id_is_cfa(id))
1984 			goto err_out;
1985 		if (ap->host->flags & ATA_HOST_IGNORE_ATA &&
1986 							ata_id_is_ata(id)) {
1987 			ata_dev_dbg(dev,
1988 				"host indicates ignore ATA devices, ignored\n");
1989 			return -ENOENT;
1990 		}
1991 	} else {
1992 		if (ata_id_is_ata(id))
1993 			goto err_out;
1994 	}
1995 
1996 	if (!tried_spinup && (id[2] == 0x37c8 || id[2] == 0x738c)) {
1997 		tried_spinup = 1;
1998 		/*
1999 		 * Drive powered-up in standby mode, and requires a specific
2000 		 * SET_FEATURES spin-up subcommand before it will accept
2001 		 * anything other than the original IDENTIFY command.
2002 		 */
2003 		err_mask = ata_dev_set_feature(dev, SETFEATURES_SPINUP, 0);
2004 		if (err_mask && id[2] != 0x738c) {
2005 			rc = -EIO;
2006 			reason = "SPINUP failed";
2007 			goto err_out;
2008 		}
2009 		/*
2010 		 * If the drive initially returned incomplete IDENTIFY info,
2011 		 * we now must reissue the IDENTIFY command.
2012 		 */
2013 		if (id[2] == 0x37c8)
2014 			goto retry;
2015 	}
2016 
2017 	if ((flags & ATA_READID_POSTRESET) && class == ATA_DEV_ATA) {
2018 		/*
2019 		 * The exact sequence expected by certain pre-ATA4 drives is:
2020 		 * SRST RESET
2021 		 * IDENTIFY (optional in early ATA)
2022 		 * INITIALIZE DEVICE PARAMETERS (later IDE and ATA)
2023 		 * anything else..
2024 		 * Some drives were very specific about that exact sequence.
2025 		 *
2026 		 * Note that ATA4 says lba is mandatory so the second check
2027 		 * should never trigger.
2028 		 */
2029 		if (ata_id_major_version(id) < 4 || !ata_id_has_lba(id)) {
2030 			err_mask = ata_dev_init_params(dev, id[3], id[6]);
2031 			if (err_mask) {
2032 				rc = -EIO;
2033 				reason = "INIT_DEV_PARAMS failed";
2034 				goto err_out;
2035 			}
2036 
2037 			/* current CHS translation info (id[53-58]) might be
2038 			 * changed. reread the identify device info.
2039 			 */
2040 			flags &= ~ATA_READID_POSTRESET;
2041 			goto retry;
2042 		}
2043 	}
2044 
2045 	*p_class = class;
2046 
2047 	return 0;
2048 
2049  err_out:
2050 	if (ata_msg_warn(ap))
2051 		ata_dev_warn(dev, "failed to IDENTIFY (%s, err_mask=0x%x)\n",
2052 			     reason, err_mask);
2053 	return rc;
2054 }
2055 
2056 static int ata_do_link_spd_horkage(struct ata_device *dev)
2057 {
2058 	struct ata_link *plink = ata_dev_phys_link(dev);
2059 	u32 target, target_limit;
2060 
2061 	if (!sata_scr_valid(plink))
2062 		return 0;
2063 
2064 	if (dev->horkage & ATA_HORKAGE_1_5_GBPS)
2065 		target = 1;
2066 	else
2067 		return 0;
2068 
2069 	target_limit = (1 << target) - 1;
2070 
2071 	/* if already on stricter limit, no need to push further */
2072 	if (plink->sata_spd_limit <= target_limit)
2073 		return 0;
2074 
2075 	plink->sata_spd_limit = target_limit;
2076 
2077 	/* Request another EH round by returning -EAGAIN if link is
2078 	 * going faster than the target speed.  Forward progress is
2079 	 * guaranteed by setting sata_spd_limit to target_limit above.
2080 	 */
2081 	if (plink->sata_spd > target) {
2082 		ata_dev_info(dev, "applying link speed limit horkage to %s\n",
2083 			     sata_spd_string(target));
2084 		return -EAGAIN;
2085 	}
2086 	return 0;
2087 }
2088 
2089 static inline u8 ata_dev_knobble(struct ata_device *dev)
2090 {
2091 	struct ata_port *ap = dev->link->ap;
2092 
2093 	if (ata_dev_blacklisted(dev) & ATA_HORKAGE_BRIDGE_OK)
2094 		return 0;
2095 
2096 	return ((ap->cbl == ATA_CBL_SATA) && (!ata_id_is_sata(dev->id)));
2097 }
2098 
2099 static int ata_dev_config_ncq(struct ata_device *dev,
2100 			       char *desc, size_t desc_sz)
2101 {
2102 	struct ata_port *ap = dev->link->ap;
2103 	int hdepth = 0, ddepth = ata_id_queue_depth(dev->id);
2104 	unsigned int err_mask;
2105 	char *aa_desc = "";
2106 
2107 	if (!ata_id_has_ncq(dev->id)) {
2108 		desc[0] = '\0';
2109 		return 0;
2110 	}
2111 	if (dev->horkage & ATA_HORKAGE_NONCQ) {
2112 		snprintf(desc, desc_sz, "NCQ (not used)");
2113 		return 0;
2114 	}
2115 	if (ap->flags & ATA_FLAG_NCQ) {
2116 		hdepth = min(ap->scsi_host->can_queue, ATA_MAX_QUEUE - 1);
2117 		dev->flags |= ATA_DFLAG_NCQ;
2118 	}
2119 
2120 	if (!(dev->horkage & ATA_HORKAGE_BROKEN_FPDMA_AA) &&
2121 		(ap->flags & ATA_FLAG_FPDMA_AA) &&
2122 		ata_id_has_fpdma_aa(dev->id)) {
2123 		err_mask = ata_dev_set_feature(dev, SETFEATURES_SATA_ENABLE,
2124 			SATA_FPDMA_AA);
2125 		if (err_mask) {
2126 			ata_dev_err(dev,
2127 				    "failed to enable AA (error_mask=0x%x)\n",
2128 				    err_mask);
2129 			if (err_mask != AC_ERR_DEV) {
2130 				dev->horkage |= ATA_HORKAGE_BROKEN_FPDMA_AA;
2131 				return -EIO;
2132 			}
2133 		} else
2134 			aa_desc = ", AA";
2135 	}
2136 
2137 	if (hdepth >= ddepth)
2138 		snprintf(desc, desc_sz, "NCQ (depth %d)%s", ddepth, aa_desc);
2139 	else
2140 		snprintf(desc, desc_sz, "NCQ (depth %d/%d)%s", hdepth,
2141 			ddepth, aa_desc);
2142 
2143 	if ((ap->flags & ATA_FLAG_FPDMA_AUX) &&
2144 	    ata_id_has_ncq_send_and_recv(dev->id)) {
2145 		err_mask = ata_read_log_page(dev, ATA_LOG_NCQ_SEND_RECV,
2146 					     0, ap->sector_buf, 1);
2147 		if (err_mask) {
2148 			ata_dev_dbg(dev,
2149 				    "failed to get NCQ Send/Recv Log Emask 0x%x\n",
2150 				    err_mask);
2151 		} else {
2152 			u8 *cmds = dev->ncq_send_recv_cmds;
2153 
2154 			dev->flags |= ATA_DFLAG_NCQ_SEND_RECV;
2155 			memcpy(cmds, ap->sector_buf, ATA_LOG_NCQ_SEND_RECV_SIZE);
2156 
2157 			if (dev->horkage & ATA_HORKAGE_NO_NCQ_TRIM) {
2158 				ata_dev_dbg(dev, "disabling queued TRIM support\n");
2159 				cmds[ATA_LOG_NCQ_SEND_RECV_DSM_OFFSET] &=
2160 					~ATA_LOG_NCQ_SEND_RECV_DSM_TRIM;
2161 			}
2162 		}
2163 	}
2164 
2165 	return 0;
2166 }
2167 
2168 /**
2169  *	ata_dev_configure - Configure the specified ATA/ATAPI device
2170  *	@dev: Target device to configure
2171  *
2172  *	Configure @dev according to @dev->id.  Generic and low-level
2173  *	driver specific fixups are also applied.
2174  *
2175  *	LOCKING:
2176  *	Kernel thread context (may sleep)
2177  *
2178  *	RETURNS:
2179  *	0 on success, -errno otherwise
2180  */
2181 int ata_dev_configure(struct ata_device *dev)
2182 {
2183 	struct ata_port *ap = dev->link->ap;
2184 	struct ata_eh_context *ehc = &dev->link->eh_context;
2185 	int print_info = ehc->i.flags & ATA_EHI_PRINTINFO;
2186 	const u16 *id = dev->id;
2187 	unsigned long xfer_mask;
2188 	unsigned int err_mask;
2189 	char revbuf[7];		/* XYZ-99\0 */
2190 	char fwrevbuf[ATA_ID_FW_REV_LEN+1];
2191 	char modelbuf[ATA_ID_PROD_LEN+1];
2192 	int rc;
2193 
2194 	if (!ata_dev_enabled(dev) && ata_msg_info(ap)) {
2195 		ata_dev_info(dev, "%s: ENTER/EXIT -- nodev\n", __func__);
2196 		return 0;
2197 	}
2198 
2199 	if (ata_msg_probe(ap))
2200 		ata_dev_dbg(dev, "%s: ENTER\n", __func__);
2201 
2202 	/* set horkage */
2203 	dev->horkage |= ata_dev_blacklisted(dev);
2204 	ata_force_horkage(dev);
2205 
2206 	if (dev->horkage & ATA_HORKAGE_DISABLE) {
2207 		ata_dev_info(dev, "unsupported device, disabling\n");
2208 		ata_dev_disable(dev);
2209 		return 0;
2210 	}
2211 
2212 	if ((!atapi_enabled || (ap->flags & ATA_FLAG_NO_ATAPI)) &&
2213 	    dev->class == ATA_DEV_ATAPI) {
2214 		ata_dev_warn(dev, "WARNING: ATAPI is %s, device ignored\n",
2215 			     atapi_enabled ? "not supported with this driver"
2216 			     : "disabled");
2217 		ata_dev_disable(dev);
2218 		return 0;
2219 	}
2220 
2221 	rc = ata_do_link_spd_horkage(dev);
2222 	if (rc)
2223 		return rc;
2224 
2225 	/* some WD SATA-1 drives have issues with LPM, turn on NOLPM for them */
2226 	if ((dev->horkage & ATA_HORKAGE_WD_BROKEN_LPM) &&
2227 	    (id[ATA_ID_SATA_CAPABILITY] & 0xe) == 0x2)
2228 		dev->horkage |= ATA_HORKAGE_NOLPM;
2229 
2230 	if (dev->horkage & ATA_HORKAGE_NOLPM) {
2231 		ata_dev_warn(dev, "LPM support broken, forcing max_power\n");
2232 		dev->link->ap->target_lpm_policy = ATA_LPM_MAX_POWER;
2233 	}
2234 
2235 	/* let ACPI work its magic */
2236 	rc = ata_acpi_on_devcfg(dev);
2237 	if (rc)
2238 		return rc;
2239 
2240 	/* massage HPA, do it early as it might change IDENTIFY data */
2241 	rc = ata_hpa_resize(dev);
2242 	if (rc)
2243 		return rc;
2244 
2245 	/* print device capabilities */
2246 	if (ata_msg_probe(ap))
2247 		ata_dev_dbg(dev,
2248 			    "%s: cfg 49:%04x 82:%04x 83:%04x 84:%04x "
2249 			    "85:%04x 86:%04x 87:%04x 88:%04x\n",
2250 			    __func__,
2251 			    id[49], id[82], id[83], id[84],
2252 			    id[85], id[86], id[87], id[88]);
2253 
2254 	/* initialize to-be-configured parameters */
2255 	dev->flags &= ~ATA_DFLAG_CFG_MASK;
2256 	dev->max_sectors = 0;
2257 	dev->cdb_len = 0;
2258 	dev->n_sectors = 0;
2259 	dev->cylinders = 0;
2260 	dev->heads = 0;
2261 	dev->sectors = 0;
2262 	dev->multi_count = 0;
2263 
2264 	/*
2265 	 * common ATA, ATAPI feature tests
2266 	 */
2267 
2268 	/* find max transfer mode; for printk only */
2269 	xfer_mask = ata_id_xfermask(id);
2270 
2271 	if (ata_msg_probe(ap))
2272 		ata_dump_id(id);
2273 
2274 	/* SCSI only uses 4-char revisions, dump full 8 chars from ATA */
2275 	ata_id_c_string(dev->id, fwrevbuf, ATA_ID_FW_REV,
2276 			sizeof(fwrevbuf));
2277 
2278 	ata_id_c_string(dev->id, modelbuf, ATA_ID_PROD,
2279 			sizeof(modelbuf));
2280 
2281 	/* ATA-specific feature tests */
2282 	if (dev->class == ATA_DEV_ATA) {
2283 		if (ata_id_is_cfa(id)) {
2284 			/* CPRM may make this media unusable */
2285 			if (id[ATA_ID_CFA_KEY_MGMT] & 1)
2286 				ata_dev_warn(dev,
2287 	"supports DRM functions and may not be fully accessible\n");
2288 			snprintf(revbuf, 7, "CFA");
2289 		} else {
2290 			snprintf(revbuf, 7, "ATA-%d", ata_id_major_version(id));
2291 			/* Warn the user if the device has TPM extensions */
2292 			if (ata_id_has_tpm(id))
2293 				ata_dev_warn(dev,
2294 	"supports DRM functions and may not be fully accessible\n");
2295 		}
2296 
2297 		dev->n_sectors = ata_id_n_sectors(id);
2298 
2299 		/* get current R/W Multiple count setting */
2300 		if ((dev->id[47] >> 8) == 0x80 && (dev->id[59] & 0x100)) {
2301 			unsigned int max = dev->id[47] & 0xff;
2302 			unsigned int cnt = dev->id[59] & 0xff;
2303 			/* only recognize/allow powers of two here */
2304 			if (is_power_of_2(max) && is_power_of_2(cnt))
2305 				if (cnt <= max)
2306 					dev->multi_count = cnt;
2307 		}
2308 
2309 		if (ata_id_has_lba(id)) {
2310 			const char *lba_desc;
2311 			char ncq_desc[24];
2312 
2313 			lba_desc = "LBA";
2314 			dev->flags |= ATA_DFLAG_LBA;
2315 			if (ata_id_has_lba48(id)) {
2316 				dev->flags |= ATA_DFLAG_LBA48;
2317 				lba_desc = "LBA48";
2318 
2319 				if (dev->n_sectors >= (1UL << 28) &&
2320 				    ata_id_has_flush_ext(id))
2321 					dev->flags |= ATA_DFLAG_FLUSH_EXT;
2322 			}
2323 
2324 			/* config NCQ */
2325 			rc = ata_dev_config_ncq(dev, ncq_desc, sizeof(ncq_desc));
2326 			if (rc)
2327 				return rc;
2328 
2329 			/* print device info to dmesg */
2330 			if (ata_msg_drv(ap) && print_info) {
2331 				ata_dev_info(dev, "%s: %s, %s, max %s\n",
2332 					     revbuf, modelbuf, fwrevbuf,
2333 					     ata_mode_string(xfer_mask));
2334 				ata_dev_info(dev,
2335 					     "%llu sectors, multi %u: %s %s\n",
2336 					(unsigned long long)dev->n_sectors,
2337 					dev->multi_count, lba_desc, ncq_desc);
2338 			}
2339 		} else {
2340 			/* CHS */
2341 
2342 			/* Default translation */
2343 			dev->cylinders	= id[1];
2344 			dev->heads	= id[3];
2345 			dev->sectors	= id[6];
2346 
2347 			if (ata_id_current_chs_valid(id)) {
2348 				/* Current CHS translation is valid. */
2349 				dev->cylinders = id[54];
2350 				dev->heads     = id[55];
2351 				dev->sectors   = id[56];
2352 			}
2353 
2354 			/* print device info to dmesg */
2355 			if (ata_msg_drv(ap) && print_info) {
2356 				ata_dev_info(dev, "%s: %s, %s, max %s\n",
2357 					     revbuf,	modelbuf, fwrevbuf,
2358 					     ata_mode_string(xfer_mask));
2359 				ata_dev_info(dev,
2360 					     "%llu sectors, multi %u, CHS %u/%u/%u\n",
2361 					     (unsigned long long)dev->n_sectors,
2362 					     dev->multi_count, dev->cylinders,
2363 					     dev->heads, dev->sectors);
2364 			}
2365 		}
2366 
2367 		/* Check and mark DevSlp capability. Get DevSlp timing variables
2368 		 * from SATA Settings page of Identify Device Data Log.
2369 		 */
2370 		if (ata_id_has_devslp(dev->id)) {
2371 			u8 *sata_setting = ap->sector_buf;
2372 			int i, j;
2373 
2374 			dev->flags |= ATA_DFLAG_DEVSLP;
2375 			err_mask = ata_read_log_page(dev,
2376 						     ATA_LOG_SATA_ID_DEV_DATA,
2377 						     ATA_LOG_SATA_SETTINGS,
2378 						     sata_setting,
2379 						     1);
2380 			if (err_mask)
2381 				ata_dev_dbg(dev,
2382 					    "failed to get Identify Device Data, Emask 0x%x\n",
2383 					    err_mask);
2384 			else
2385 				for (i = 0; i < ATA_LOG_DEVSLP_SIZE; i++) {
2386 					j = ATA_LOG_DEVSLP_OFFSET + i;
2387 					dev->devslp_timing[i] = sata_setting[j];
2388 				}
2389 		}
2390 
2391 		dev->cdb_len = 16;
2392 	}
2393 
2394 	/* ATAPI-specific feature tests */
2395 	else if (dev->class == ATA_DEV_ATAPI) {
2396 		const char *cdb_intr_string = "";
2397 		const char *atapi_an_string = "";
2398 		const char *dma_dir_string = "";
2399 		u32 sntf;
2400 
2401 		rc = atapi_cdb_len(id);
2402 		if ((rc < 12) || (rc > ATAPI_CDB_LEN)) {
2403 			if (ata_msg_warn(ap))
2404 				ata_dev_warn(dev, "unsupported CDB len\n");
2405 			rc = -EINVAL;
2406 			goto err_out_nosup;
2407 		}
2408 		dev->cdb_len = (unsigned int) rc;
2409 
2410 		/* Enable ATAPI AN if both the host and device have
2411 		 * the support.  If PMP is attached, SNTF is required
2412 		 * to enable ATAPI AN to discern between PHY status
2413 		 * changed notifications and ATAPI ANs.
2414 		 */
2415 		if (atapi_an &&
2416 		    (ap->flags & ATA_FLAG_AN) && ata_id_has_atapi_AN(id) &&
2417 		    (!sata_pmp_attached(ap) ||
2418 		     sata_scr_read(&ap->link, SCR_NOTIFICATION, &sntf) == 0)) {
2419 			/* issue SET feature command to turn this on */
2420 			err_mask = ata_dev_set_feature(dev,
2421 					SETFEATURES_SATA_ENABLE, SATA_AN);
2422 			if (err_mask)
2423 				ata_dev_err(dev,
2424 					    "failed to enable ATAPI AN (err_mask=0x%x)\n",
2425 					    err_mask);
2426 			else {
2427 				dev->flags |= ATA_DFLAG_AN;
2428 				atapi_an_string = ", ATAPI AN";
2429 			}
2430 		}
2431 
2432 		if (ata_id_cdb_intr(dev->id)) {
2433 			dev->flags |= ATA_DFLAG_CDB_INTR;
2434 			cdb_intr_string = ", CDB intr";
2435 		}
2436 
2437 		if (atapi_dmadir || (dev->horkage & ATA_HORKAGE_ATAPI_DMADIR) || atapi_id_dmadir(dev->id)) {
2438 			dev->flags |= ATA_DFLAG_DMADIR;
2439 			dma_dir_string = ", DMADIR";
2440 		}
2441 
2442 		if (ata_id_has_da(dev->id)) {
2443 			dev->flags |= ATA_DFLAG_DA;
2444 			zpodd_init(dev);
2445 		}
2446 
2447 		/* print device info to dmesg */
2448 		if (ata_msg_drv(ap) && print_info)
2449 			ata_dev_info(dev,
2450 				     "ATAPI: %s, %s, max %s%s%s%s\n",
2451 				     modelbuf, fwrevbuf,
2452 				     ata_mode_string(xfer_mask),
2453 				     cdb_intr_string, atapi_an_string,
2454 				     dma_dir_string);
2455 	}
2456 
2457 	/* determine max_sectors */
2458 	dev->max_sectors = ATA_MAX_SECTORS;
2459 	if (dev->flags & ATA_DFLAG_LBA48)
2460 		dev->max_sectors = ATA_MAX_SECTORS_LBA48;
2461 
2462 	/* Limit PATA drive on SATA cable bridge transfers to udma5,
2463 	   200 sectors */
2464 	if (ata_dev_knobble(dev)) {
2465 		if (ata_msg_drv(ap) && print_info)
2466 			ata_dev_info(dev, "applying bridge limits\n");
2467 		dev->udma_mask &= ATA_UDMA5;
2468 		dev->max_sectors = ATA_MAX_SECTORS;
2469 	}
2470 
2471 	if ((dev->class == ATA_DEV_ATAPI) &&
2472 	    (atapi_command_packet_set(id) == TYPE_TAPE)) {
2473 		dev->max_sectors = ATA_MAX_SECTORS_TAPE;
2474 		dev->horkage |= ATA_HORKAGE_STUCK_ERR;
2475 	}
2476 
2477 	if (dev->horkage & ATA_HORKAGE_MAX_SEC_128)
2478 		dev->max_sectors = min_t(unsigned int, ATA_MAX_SECTORS_128,
2479 					 dev->max_sectors);
2480 
2481 	if (dev->horkage & ATA_HORKAGE_MAX_SEC_LBA48)
2482 		dev->max_sectors = ATA_MAX_SECTORS_LBA48;
2483 
2484 	if (ap->ops->dev_config)
2485 		ap->ops->dev_config(dev);
2486 
2487 	if (dev->horkage & ATA_HORKAGE_DIAGNOSTIC) {
2488 		/* Let the user know. We don't want to disallow opens for
2489 		   rescue purposes, or in case the vendor is just a blithering
2490 		   idiot. Do this after the dev_config call as some controllers
2491 		   with buggy firmware may want to avoid reporting false device
2492 		   bugs */
2493 
2494 		if (print_info) {
2495 			ata_dev_warn(dev,
2496 "Drive reports diagnostics failure. This may indicate a drive\n");
2497 			ata_dev_warn(dev,
2498 "fault or invalid emulation. Contact drive vendor for information.\n");
2499 		}
2500 	}
2501 
2502 	if ((dev->horkage & ATA_HORKAGE_FIRMWARE_WARN) && print_info) {
2503 		ata_dev_warn(dev, "WARNING: device requires firmware update to be fully functional\n");
2504 		ata_dev_warn(dev, "         contact the vendor or visit http://ata.wiki.kernel.org\n");
2505 	}
2506 
2507 	return 0;
2508 
2509 err_out_nosup:
2510 	if (ata_msg_probe(ap))
2511 		ata_dev_dbg(dev, "%s: EXIT, err\n", __func__);
2512 	return rc;
2513 }
2514 
2515 /**
2516  *	ata_cable_40wire	-	return 40 wire cable type
2517  *	@ap: port
2518  *
2519  *	Helper method for drivers which want to hardwire 40 wire cable
2520  *	detection.
2521  */
2522 
2523 int ata_cable_40wire(struct ata_port *ap)
2524 {
2525 	return ATA_CBL_PATA40;
2526 }
2527 
2528 /**
2529  *	ata_cable_80wire	-	return 80 wire cable type
2530  *	@ap: port
2531  *
2532  *	Helper method for drivers which want to hardwire 80 wire cable
2533  *	detection.
2534  */
2535 
2536 int ata_cable_80wire(struct ata_port *ap)
2537 {
2538 	return ATA_CBL_PATA80;
2539 }
2540 
2541 /**
2542  *	ata_cable_unknown	-	return unknown PATA cable.
2543  *	@ap: port
2544  *
2545  *	Helper method for drivers which have no PATA cable detection.
2546  */
2547 
2548 int ata_cable_unknown(struct ata_port *ap)
2549 {
2550 	return ATA_CBL_PATA_UNK;
2551 }
2552 
2553 /**
2554  *	ata_cable_ignore	-	return ignored PATA cable.
2555  *	@ap: port
2556  *
2557  *	Helper method for drivers which don't use cable type to limit
2558  *	transfer mode.
2559  */
2560 int ata_cable_ignore(struct ata_port *ap)
2561 {
2562 	return ATA_CBL_PATA_IGN;
2563 }
2564 
2565 /**
2566  *	ata_cable_sata	-	return SATA cable type
2567  *	@ap: port
2568  *
2569  *	Helper method for drivers which have SATA cables
2570  */
2571 
2572 int ata_cable_sata(struct ata_port *ap)
2573 {
2574 	return ATA_CBL_SATA;
2575 }
2576 
2577 /**
2578  *	ata_bus_probe - Reset and probe ATA bus
2579  *	@ap: Bus to probe
2580  *
2581  *	Master ATA bus probing function.  Initiates a hardware-dependent
2582  *	bus reset, then attempts to identify any devices found on
2583  *	the bus.
2584  *
2585  *	LOCKING:
2586  *	PCI/etc. bus probe sem.
2587  *
2588  *	RETURNS:
2589  *	Zero on success, negative errno otherwise.
2590  */
2591 
2592 int ata_bus_probe(struct ata_port *ap)
2593 {
2594 	unsigned int classes[ATA_MAX_DEVICES];
2595 	int tries[ATA_MAX_DEVICES];
2596 	int rc;
2597 	struct ata_device *dev;
2598 
2599 	ata_for_each_dev(dev, &ap->link, ALL)
2600 		tries[dev->devno] = ATA_PROBE_MAX_TRIES;
2601 
2602  retry:
2603 	ata_for_each_dev(dev, &ap->link, ALL) {
2604 		/* If we issue an SRST then an ATA drive (not ATAPI)
2605 		 * may change configuration and be in PIO0 timing. If
2606 		 * we do a hard reset (or are coming from power on)
2607 		 * this is true for ATA or ATAPI. Until we've set a
2608 		 * suitable controller mode we should not touch the
2609 		 * bus as we may be talking too fast.
2610 		 */
2611 		dev->pio_mode = XFER_PIO_0;
2612 		dev->dma_mode = 0xff;
2613 
2614 		/* If the controller has a pio mode setup function
2615 		 * then use it to set the chipset to rights. Don't
2616 		 * touch the DMA setup as that will be dealt with when
2617 		 * configuring devices.
2618 		 */
2619 		if (ap->ops->set_piomode)
2620 			ap->ops->set_piomode(ap, dev);
2621 	}
2622 
2623 	/* reset and determine device classes */
2624 	ap->ops->phy_reset(ap);
2625 
2626 	ata_for_each_dev(dev, &ap->link, ALL) {
2627 		if (dev->class != ATA_DEV_UNKNOWN)
2628 			classes[dev->devno] = dev->class;
2629 		else
2630 			classes[dev->devno] = ATA_DEV_NONE;
2631 
2632 		dev->class = ATA_DEV_UNKNOWN;
2633 	}
2634 
2635 	/* read IDENTIFY page and configure devices. We have to do the identify
2636 	   specific sequence bass-ackwards so that PDIAG- is released by
2637 	   the slave device */
2638 
2639 	ata_for_each_dev(dev, &ap->link, ALL_REVERSE) {
2640 		if (tries[dev->devno])
2641 			dev->class = classes[dev->devno];
2642 
2643 		if (!ata_dev_enabled(dev))
2644 			continue;
2645 
2646 		rc = ata_dev_read_id(dev, &dev->class, ATA_READID_POSTRESET,
2647 				     dev->id);
2648 		if (rc)
2649 			goto fail;
2650 	}
2651 
2652 	/* Now ask for the cable type as PDIAG- should have been released */
2653 	if (ap->ops->cable_detect)
2654 		ap->cbl = ap->ops->cable_detect(ap);
2655 
2656 	/* We may have SATA bridge glue hiding here irrespective of
2657 	 * the reported cable types and sensed types.  When SATA
2658 	 * drives indicate we have a bridge, we don't know which end
2659 	 * of the link the bridge is which is a problem.
2660 	 */
2661 	ata_for_each_dev(dev, &ap->link, ENABLED)
2662 		if (ata_id_is_sata(dev->id))
2663 			ap->cbl = ATA_CBL_SATA;
2664 
2665 	/* After the identify sequence we can now set up the devices. We do
2666 	   this in the normal order so that the user doesn't get confused */
2667 
2668 	ata_for_each_dev(dev, &ap->link, ENABLED) {
2669 		ap->link.eh_context.i.flags |= ATA_EHI_PRINTINFO;
2670 		rc = ata_dev_configure(dev);
2671 		ap->link.eh_context.i.flags &= ~ATA_EHI_PRINTINFO;
2672 		if (rc)
2673 			goto fail;
2674 	}
2675 
2676 	/* configure transfer mode */
2677 	rc = ata_set_mode(&ap->link, &dev);
2678 	if (rc)
2679 		goto fail;
2680 
2681 	ata_for_each_dev(dev, &ap->link, ENABLED)
2682 		return 0;
2683 
2684 	return -ENODEV;
2685 
2686  fail:
2687 	tries[dev->devno]--;
2688 
2689 	switch (rc) {
2690 	case -EINVAL:
2691 		/* eeek, something went very wrong, give up */
2692 		tries[dev->devno] = 0;
2693 		break;
2694 
2695 	case -ENODEV:
2696 		/* give it just one more chance */
2697 		tries[dev->devno] = min(tries[dev->devno], 1);
2698 	case -EIO:
2699 		if (tries[dev->devno] == 1) {
2700 			/* This is the last chance, better to slow
2701 			 * down than lose it.
2702 			 */
2703 			sata_down_spd_limit(&ap->link, 0);
2704 			ata_down_xfermask_limit(dev, ATA_DNXFER_PIO);
2705 		}
2706 	}
2707 
2708 	if (!tries[dev->devno])
2709 		ata_dev_disable(dev);
2710 
2711 	goto retry;
2712 }
2713 
2714 /**
2715  *	sata_print_link_status - Print SATA link status
2716  *	@link: SATA link to printk link status about
2717  *
2718  *	This function prints link speed and status of a SATA link.
2719  *
2720  *	LOCKING:
2721  *	None.
2722  */
2723 static void sata_print_link_status(struct ata_link *link)
2724 {
2725 	u32 sstatus, scontrol, tmp;
2726 
2727 	if (sata_scr_read(link, SCR_STATUS, &sstatus))
2728 		return;
2729 	sata_scr_read(link, SCR_CONTROL, &scontrol);
2730 
2731 	if (ata_phys_link_online(link)) {
2732 		tmp = (sstatus >> 4) & 0xf;
2733 		ata_link_info(link, "SATA link up %s (SStatus %X SControl %X)\n",
2734 			      sata_spd_string(tmp), sstatus, scontrol);
2735 	} else {
2736 		ata_link_info(link, "SATA link down (SStatus %X SControl %X)\n",
2737 			      sstatus, scontrol);
2738 	}
2739 }
2740 
2741 /**
2742  *	ata_dev_pair		-	return other device on cable
2743  *	@adev: device
2744  *
2745  *	Obtain the other device on the same cable, or if none is
2746  *	present NULL is returned
2747  */
2748 
2749 struct ata_device *ata_dev_pair(struct ata_device *adev)
2750 {
2751 	struct ata_link *link = adev->link;
2752 	struct ata_device *pair = &link->device[1 - adev->devno];
2753 	if (!ata_dev_enabled(pair))
2754 		return NULL;
2755 	return pair;
2756 }
2757 
2758 /**
2759  *	sata_down_spd_limit - adjust SATA spd limit downward
2760  *	@link: Link to adjust SATA spd limit for
2761  *	@spd_limit: Additional limit
2762  *
2763  *	Adjust SATA spd limit of @link downward.  Note that this
2764  *	function only adjusts the limit.  The change must be applied
2765  *	using sata_set_spd().
2766  *
2767  *	If @spd_limit is non-zero, the speed is limited to equal to or
2768  *	lower than @spd_limit if such speed is supported.  If
2769  *	@spd_limit is slower than any supported speed, only the lowest
2770  *	supported speed is allowed.
2771  *
2772  *	LOCKING:
2773  *	Inherited from caller.
2774  *
2775  *	RETURNS:
2776  *	0 on success, negative errno on failure
2777  */
2778 int sata_down_spd_limit(struct ata_link *link, u32 spd_limit)
2779 {
2780 	u32 sstatus, spd, mask;
2781 	int rc, bit;
2782 
2783 	if (!sata_scr_valid(link))
2784 		return -EOPNOTSUPP;
2785 
2786 	/* If SCR can be read, use it to determine the current SPD.
2787 	 * If not, use cached value in link->sata_spd.
2788 	 */
2789 	rc = sata_scr_read(link, SCR_STATUS, &sstatus);
2790 	if (rc == 0 && ata_sstatus_online(sstatus))
2791 		spd = (sstatus >> 4) & 0xf;
2792 	else
2793 		spd = link->sata_spd;
2794 
2795 	mask = link->sata_spd_limit;
2796 	if (mask <= 1)
2797 		return -EINVAL;
2798 
2799 	/* unconditionally mask off the highest bit */
2800 	bit = fls(mask) - 1;
2801 	mask &= ~(1 << bit);
2802 
2803 	/* Mask off all speeds higher than or equal to the current
2804 	 * one.  Force 1.5Gbps if current SPD is not available.
2805 	 */
2806 	if (spd > 1)
2807 		mask &= (1 << (spd - 1)) - 1;
2808 	else
2809 		mask &= 1;
2810 
2811 	/* were we already at the bottom? */
2812 	if (!mask)
2813 		return -EINVAL;
2814 
2815 	if (spd_limit) {
2816 		if (mask & ((1 << spd_limit) - 1))
2817 			mask &= (1 << spd_limit) - 1;
2818 		else {
2819 			bit = ffs(mask) - 1;
2820 			mask = 1 << bit;
2821 		}
2822 	}
2823 
2824 	link->sata_spd_limit = mask;
2825 
2826 	ata_link_warn(link, "limiting SATA link speed to %s\n",
2827 		      sata_spd_string(fls(mask)));
2828 
2829 	return 0;
2830 }
2831 
2832 static int __sata_set_spd_needed(struct ata_link *link, u32 *scontrol)
2833 {
2834 	struct ata_link *host_link = &link->ap->link;
2835 	u32 limit, target, spd;
2836 
2837 	limit = link->sata_spd_limit;
2838 
2839 	/* Don't configure downstream link faster than upstream link.
2840 	 * It doesn't speed up anything and some PMPs choke on such
2841 	 * configuration.
2842 	 */
2843 	if (!ata_is_host_link(link) && host_link->sata_spd)
2844 		limit &= (1 << host_link->sata_spd) - 1;
2845 
2846 	if (limit == UINT_MAX)
2847 		target = 0;
2848 	else
2849 		target = fls(limit);
2850 
2851 	spd = (*scontrol >> 4) & 0xf;
2852 	*scontrol = (*scontrol & ~0xf0) | ((target & 0xf) << 4);
2853 
2854 	return spd != target;
2855 }
2856 
2857 /**
2858  *	sata_set_spd_needed - is SATA spd configuration needed
2859  *	@link: Link in question
2860  *
2861  *	Test whether the spd limit in SControl matches
2862  *	@link->sata_spd_limit.  This function is used to determine
2863  *	whether hardreset is necessary to apply SATA spd
2864  *	configuration.
2865  *
2866  *	LOCKING:
2867  *	Inherited from caller.
2868  *
2869  *	RETURNS:
2870  *	1 if SATA spd configuration is needed, 0 otherwise.
2871  */
2872 static int sata_set_spd_needed(struct ata_link *link)
2873 {
2874 	u32 scontrol;
2875 
2876 	if (sata_scr_read(link, SCR_CONTROL, &scontrol))
2877 		return 1;
2878 
2879 	return __sata_set_spd_needed(link, &scontrol);
2880 }
2881 
2882 /**
2883  *	sata_set_spd - set SATA spd according to spd limit
2884  *	@link: Link to set SATA spd for
2885  *
2886  *	Set SATA spd of @link according to sata_spd_limit.
2887  *
2888  *	LOCKING:
2889  *	Inherited from caller.
2890  *
2891  *	RETURNS:
2892  *	0 if spd doesn't need to be changed, 1 if spd has been
2893  *	changed.  Negative errno if SCR registers are inaccessible.
2894  */
2895 int sata_set_spd(struct ata_link *link)
2896 {
2897 	u32 scontrol;
2898 	int rc;
2899 
2900 	if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
2901 		return rc;
2902 
2903 	if (!__sata_set_spd_needed(link, &scontrol))
2904 		return 0;
2905 
2906 	if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
2907 		return rc;
2908 
2909 	return 1;
2910 }
2911 
2912 /*
2913  * This mode timing computation functionality is ported over from
2914  * drivers/ide/ide-timing.h and was originally written by Vojtech Pavlik
2915  */
2916 /*
2917  * PIO 0-4, MWDMA 0-2 and UDMA 0-6 timings (in nanoseconds).
2918  * These were taken from ATA/ATAPI-6 standard, rev 0a, except
2919  * for UDMA6, which is currently supported only by Maxtor drives.
2920  *
2921  * For PIO 5/6 MWDMA 3/4 see the CFA specification 3.0.
2922  */
2923 
2924 static const struct ata_timing ata_timing[] = {
2925 /*	{ XFER_PIO_SLOW, 120, 290, 240, 960, 290, 240, 0,  960,   0 }, */
2926 	{ XFER_PIO_0,     70, 290, 240, 600, 165, 150, 0,  600,   0 },
2927 	{ XFER_PIO_1,     50, 290,  93, 383, 125, 100, 0,  383,   0 },
2928 	{ XFER_PIO_2,     30, 290,  40, 330, 100,  90, 0,  240,   0 },
2929 	{ XFER_PIO_3,     30,  80,  70, 180,  80,  70, 0,  180,   0 },
2930 	{ XFER_PIO_4,     25,  70,  25, 120,  70,  25, 0,  120,   0 },
2931 	{ XFER_PIO_5,     15,  65,  25, 100,  65,  25, 0,  100,   0 },
2932 	{ XFER_PIO_6,     10,  55,  20,  80,  55,  20, 0,   80,   0 },
2933 
2934 	{ XFER_SW_DMA_0, 120,   0,   0,   0, 480, 480, 50, 960,   0 },
2935 	{ XFER_SW_DMA_1,  90,   0,   0,   0, 240, 240, 30, 480,   0 },
2936 	{ XFER_SW_DMA_2,  60,   0,   0,   0, 120, 120, 20, 240,   0 },
2937 
2938 	{ XFER_MW_DMA_0,  60,   0,   0,   0, 215, 215, 20, 480,   0 },
2939 	{ XFER_MW_DMA_1,  45,   0,   0,   0,  80,  50, 5,  150,   0 },
2940 	{ XFER_MW_DMA_2,  25,   0,   0,   0,  70,  25, 5,  120,   0 },
2941 	{ XFER_MW_DMA_3,  25,   0,   0,   0,  65,  25, 5,  100,   0 },
2942 	{ XFER_MW_DMA_4,  25,   0,   0,   0,  55,  20, 5,   80,   0 },
2943 
2944 /*	{ XFER_UDMA_SLOW,  0,   0,   0,   0,   0,   0, 0,    0, 150 }, */
2945 	{ XFER_UDMA_0,     0,   0,   0,   0,   0,   0, 0,    0, 120 },
2946 	{ XFER_UDMA_1,     0,   0,   0,   0,   0,   0, 0,    0,  80 },
2947 	{ XFER_UDMA_2,     0,   0,   0,   0,   0,   0, 0,    0,  60 },
2948 	{ XFER_UDMA_3,     0,   0,   0,   0,   0,   0, 0,    0,  45 },
2949 	{ XFER_UDMA_4,     0,   0,   0,   0,   0,   0, 0,    0,  30 },
2950 	{ XFER_UDMA_5,     0,   0,   0,   0,   0,   0, 0,    0,  20 },
2951 	{ XFER_UDMA_6,     0,   0,   0,   0,   0,   0, 0,    0,  15 },
2952 
2953 	{ 0xFF }
2954 };
2955 
2956 #define ENOUGH(v, unit)		(((v)-1)/(unit)+1)
2957 #define EZ(v, unit)		((v)?ENOUGH(v, unit):0)
2958 
2959 static void ata_timing_quantize(const struct ata_timing *t, struct ata_timing *q, int T, int UT)
2960 {
2961 	q->setup	= EZ(t->setup      * 1000,  T);
2962 	q->act8b	= EZ(t->act8b      * 1000,  T);
2963 	q->rec8b	= EZ(t->rec8b      * 1000,  T);
2964 	q->cyc8b	= EZ(t->cyc8b      * 1000,  T);
2965 	q->active	= EZ(t->active     * 1000,  T);
2966 	q->recover	= EZ(t->recover    * 1000,  T);
2967 	q->dmack_hold	= EZ(t->dmack_hold * 1000,  T);
2968 	q->cycle	= EZ(t->cycle      * 1000,  T);
2969 	q->udma		= EZ(t->udma       * 1000, UT);
2970 }
2971 
2972 void ata_timing_merge(const struct ata_timing *a, const struct ata_timing *b,
2973 		      struct ata_timing *m, unsigned int what)
2974 {
2975 	if (what & ATA_TIMING_SETUP  ) m->setup   = max(a->setup,   b->setup);
2976 	if (what & ATA_TIMING_ACT8B  ) m->act8b   = max(a->act8b,   b->act8b);
2977 	if (what & ATA_TIMING_REC8B  ) m->rec8b   = max(a->rec8b,   b->rec8b);
2978 	if (what & ATA_TIMING_CYC8B  ) m->cyc8b   = max(a->cyc8b,   b->cyc8b);
2979 	if (what & ATA_TIMING_ACTIVE ) m->active  = max(a->active,  b->active);
2980 	if (what & ATA_TIMING_RECOVER) m->recover = max(a->recover, b->recover);
2981 	if (what & ATA_TIMING_DMACK_HOLD) m->dmack_hold = max(a->dmack_hold, b->dmack_hold);
2982 	if (what & ATA_TIMING_CYCLE  ) m->cycle   = max(a->cycle,   b->cycle);
2983 	if (what & ATA_TIMING_UDMA   ) m->udma    = max(a->udma,    b->udma);
2984 }
2985 
2986 const struct ata_timing *ata_timing_find_mode(u8 xfer_mode)
2987 {
2988 	const struct ata_timing *t = ata_timing;
2989 
2990 	while (xfer_mode > t->mode)
2991 		t++;
2992 
2993 	if (xfer_mode == t->mode)
2994 		return t;
2995 
2996 	WARN_ONCE(true, "%s: unable to find timing for xfer_mode 0x%x\n",
2997 			__func__, xfer_mode);
2998 
2999 	return NULL;
3000 }
3001 
3002 int ata_timing_compute(struct ata_device *adev, unsigned short speed,
3003 		       struct ata_timing *t, int T, int UT)
3004 {
3005 	const u16 *id = adev->id;
3006 	const struct ata_timing *s;
3007 	struct ata_timing p;
3008 
3009 	/*
3010 	 * Find the mode.
3011 	 */
3012 
3013 	if (!(s = ata_timing_find_mode(speed)))
3014 		return -EINVAL;
3015 
3016 	memcpy(t, s, sizeof(*s));
3017 
3018 	/*
3019 	 * If the drive is an EIDE drive, it can tell us it needs extended
3020 	 * PIO/MW_DMA cycle timing.
3021 	 */
3022 
3023 	if (id[ATA_ID_FIELD_VALID] & 2) {	/* EIDE drive */
3024 		memset(&p, 0, sizeof(p));
3025 
3026 		if (speed >= XFER_PIO_0 && speed < XFER_SW_DMA_0) {
3027 			if (speed <= XFER_PIO_2)
3028 				p.cycle = p.cyc8b = id[ATA_ID_EIDE_PIO];
3029 			else if ((speed <= XFER_PIO_4) ||
3030 				 (speed == XFER_PIO_5 && !ata_id_is_cfa(id)))
3031 				p.cycle = p.cyc8b = id[ATA_ID_EIDE_PIO_IORDY];
3032 		} else if (speed >= XFER_MW_DMA_0 && speed <= XFER_MW_DMA_2)
3033 			p.cycle = id[ATA_ID_EIDE_DMA_MIN];
3034 
3035 		ata_timing_merge(&p, t, t, ATA_TIMING_CYCLE | ATA_TIMING_CYC8B);
3036 	}
3037 
3038 	/*
3039 	 * Convert the timing to bus clock counts.
3040 	 */
3041 
3042 	ata_timing_quantize(t, t, T, UT);
3043 
3044 	/*
3045 	 * Even in DMA/UDMA modes we still use PIO access for IDENTIFY,
3046 	 * S.M.A.R.T * and some other commands. We have to ensure that the
3047 	 * DMA cycle timing is slower/equal than the fastest PIO timing.
3048 	 */
3049 
3050 	if (speed > XFER_PIO_6) {
3051 		ata_timing_compute(adev, adev->pio_mode, &p, T, UT);
3052 		ata_timing_merge(&p, t, t, ATA_TIMING_ALL);
3053 	}
3054 
3055 	/*
3056 	 * Lengthen active & recovery time so that cycle time is correct.
3057 	 */
3058 
3059 	if (t->act8b + t->rec8b < t->cyc8b) {
3060 		t->act8b += (t->cyc8b - (t->act8b + t->rec8b)) / 2;
3061 		t->rec8b = t->cyc8b - t->act8b;
3062 	}
3063 
3064 	if (t->active + t->recover < t->cycle) {
3065 		t->active += (t->cycle - (t->active + t->recover)) / 2;
3066 		t->recover = t->cycle - t->active;
3067 	}
3068 
3069 	/* In a few cases quantisation may produce enough errors to
3070 	   leave t->cycle too low for the sum of active and recovery
3071 	   if so we must correct this */
3072 	if (t->active + t->recover > t->cycle)
3073 		t->cycle = t->active + t->recover;
3074 
3075 	return 0;
3076 }
3077 
3078 /**
3079  *	ata_timing_cycle2mode - find xfer mode for the specified cycle duration
3080  *	@xfer_shift: ATA_SHIFT_* value for transfer type to examine.
3081  *	@cycle: cycle duration in ns
3082  *
3083  *	Return matching xfer mode for @cycle.  The returned mode is of
3084  *	the transfer type specified by @xfer_shift.  If @cycle is too
3085  *	slow for @xfer_shift, 0xff is returned.  If @cycle is faster
3086  *	than the fastest known mode, the fasted mode is returned.
3087  *
3088  *	LOCKING:
3089  *	None.
3090  *
3091  *	RETURNS:
3092  *	Matching xfer_mode, 0xff if no match found.
3093  */
3094 u8 ata_timing_cycle2mode(unsigned int xfer_shift, int cycle)
3095 {
3096 	u8 base_mode = 0xff, last_mode = 0xff;
3097 	const struct ata_xfer_ent *ent;
3098 	const struct ata_timing *t;
3099 
3100 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
3101 		if (ent->shift == xfer_shift)
3102 			base_mode = ent->base;
3103 
3104 	for (t = ata_timing_find_mode(base_mode);
3105 	     t && ata_xfer_mode2shift(t->mode) == xfer_shift; t++) {
3106 		unsigned short this_cycle;
3107 
3108 		switch (xfer_shift) {
3109 		case ATA_SHIFT_PIO:
3110 		case ATA_SHIFT_MWDMA:
3111 			this_cycle = t->cycle;
3112 			break;
3113 		case ATA_SHIFT_UDMA:
3114 			this_cycle = t->udma;
3115 			break;
3116 		default:
3117 			return 0xff;
3118 		}
3119 
3120 		if (cycle > this_cycle)
3121 			break;
3122 
3123 		last_mode = t->mode;
3124 	}
3125 
3126 	return last_mode;
3127 }
3128 
3129 /**
3130  *	ata_down_xfermask_limit - adjust dev xfer masks downward
3131  *	@dev: Device to adjust xfer masks
3132  *	@sel: ATA_DNXFER_* selector
3133  *
3134  *	Adjust xfer masks of @dev downward.  Note that this function
3135  *	does not apply the change.  Invoking ata_set_mode() afterwards
3136  *	will apply the limit.
3137  *
3138  *	LOCKING:
3139  *	Inherited from caller.
3140  *
3141  *	RETURNS:
3142  *	0 on success, negative errno on failure
3143  */
3144 int ata_down_xfermask_limit(struct ata_device *dev, unsigned int sel)
3145 {
3146 	char buf[32];
3147 	unsigned long orig_mask, xfer_mask;
3148 	unsigned long pio_mask, mwdma_mask, udma_mask;
3149 	int quiet, highbit;
3150 
3151 	quiet = !!(sel & ATA_DNXFER_QUIET);
3152 	sel &= ~ATA_DNXFER_QUIET;
3153 
3154 	xfer_mask = orig_mask = ata_pack_xfermask(dev->pio_mask,
3155 						  dev->mwdma_mask,
3156 						  dev->udma_mask);
3157 	ata_unpack_xfermask(xfer_mask, &pio_mask, &mwdma_mask, &udma_mask);
3158 
3159 	switch (sel) {
3160 	case ATA_DNXFER_PIO:
3161 		highbit = fls(pio_mask) - 1;
3162 		pio_mask &= ~(1 << highbit);
3163 		break;
3164 
3165 	case ATA_DNXFER_DMA:
3166 		if (udma_mask) {
3167 			highbit = fls(udma_mask) - 1;
3168 			udma_mask &= ~(1 << highbit);
3169 			if (!udma_mask)
3170 				return -ENOENT;
3171 		} else if (mwdma_mask) {
3172 			highbit = fls(mwdma_mask) - 1;
3173 			mwdma_mask &= ~(1 << highbit);
3174 			if (!mwdma_mask)
3175 				return -ENOENT;
3176 		}
3177 		break;
3178 
3179 	case ATA_DNXFER_40C:
3180 		udma_mask &= ATA_UDMA_MASK_40C;
3181 		break;
3182 
3183 	case ATA_DNXFER_FORCE_PIO0:
3184 		pio_mask &= 1;
3185 	case ATA_DNXFER_FORCE_PIO:
3186 		mwdma_mask = 0;
3187 		udma_mask = 0;
3188 		break;
3189 
3190 	default:
3191 		BUG();
3192 	}
3193 
3194 	xfer_mask &= ata_pack_xfermask(pio_mask, mwdma_mask, udma_mask);
3195 
3196 	if (!(xfer_mask & ATA_MASK_PIO) || xfer_mask == orig_mask)
3197 		return -ENOENT;
3198 
3199 	if (!quiet) {
3200 		if (xfer_mask & (ATA_MASK_MWDMA | ATA_MASK_UDMA))
3201 			snprintf(buf, sizeof(buf), "%s:%s",
3202 				 ata_mode_string(xfer_mask),
3203 				 ata_mode_string(xfer_mask & ATA_MASK_PIO));
3204 		else
3205 			snprintf(buf, sizeof(buf), "%s",
3206 				 ata_mode_string(xfer_mask));
3207 
3208 		ata_dev_warn(dev, "limiting speed to %s\n", buf);
3209 	}
3210 
3211 	ata_unpack_xfermask(xfer_mask, &dev->pio_mask, &dev->mwdma_mask,
3212 			    &dev->udma_mask);
3213 
3214 	return 0;
3215 }
3216 
3217 static int ata_dev_set_mode(struct ata_device *dev)
3218 {
3219 	struct ata_port *ap = dev->link->ap;
3220 	struct ata_eh_context *ehc = &dev->link->eh_context;
3221 	const bool nosetxfer = dev->horkage & ATA_HORKAGE_NOSETXFER;
3222 	const char *dev_err_whine = "";
3223 	int ign_dev_err = 0;
3224 	unsigned int err_mask = 0;
3225 	int rc;
3226 
3227 	dev->flags &= ~ATA_DFLAG_PIO;
3228 	if (dev->xfer_shift == ATA_SHIFT_PIO)
3229 		dev->flags |= ATA_DFLAG_PIO;
3230 
3231 	if (nosetxfer && ap->flags & ATA_FLAG_SATA && ata_id_is_sata(dev->id))
3232 		dev_err_whine = " (SET_XFERMODE skipped)";
3233 	else {
3234 		if (nosetxfer)
3235 			ata_dev_warn(dev,
3236 				     "NOSETXFER but PATA detected - can't "
3237 				     "skip SETXFER, might malfunction\n");
3238 		err_mask = ata_dev_set_xfermode(dev);
3239 	}
3240 
3241 	if (err_mask & ~AC_ERR_DEV)
3242 		goto fail;
3243 
3244 	/* revalidate */
3245 	ehc->i.flags |= ATA_EHI_POST_SETMODE;
3246 	rc = ata_dev_revalidate(dev, ATA_DEV_UNKNOWN, 0);
3247 	ehc->i.flags &= ~ATA_EHI_POST_SETMODE;
3248 	if (rc)
3249 		return rc;
3250 
3251 	if (dev->xfer_shift == ATA_SHIFT_PIO) {
3252 		/* Old CFA may refuse this command, which is just fine */
3253 		if (ata_id_is_cfa(dev->id))
3254 			ign_dev_err = 1;
3255 		/* Catch several broken garbage emulations plus some pre
3256 		   ATA devices */
3257 		if (ata_id_major_version(dev->id) == 0 &&
3258 					dev->pio_mode <= XFER_PIO_2)
3259 			ign_dev_err = 1;
3260 		/* Some very old devices and some bad newer ones fail
3261 		   any kind of SET_XFERMODE request but support PIO0-2
3262 		   timings and no IORDY */
3263 		if (!ata_id_has_iordy(dev->id) && dev->pio_mode <= XFER_PIO_2)
3264 			ign_dev_err = 1;
3265 	}
3266 	/* Early MWDMA devices do DMA but don't allow DMA mode setting.
3267 	   Don't fail an MWDMA0 set IFF the device indicates it is in MWDMA0 */
3268 	if (dev->xfer_shift == ATA_SHIFT_MWDMA &&
3269 	    dev->dma_mode == XFER_MW_DMA_0 &&
3270 	    (dev->id[63] >> 8) & 1)
3271 		ign_dev_err = 1;
3272 
3273 	/* if the device is actually configured correctly, ignore dev err */
3274 	if (dev->xfer_mode == ata_xfer_mask2mode(ata_id_xfermask(dev->id)))
3275 		ign_dev_err = 1;
3276 
3277 	if (err_mask & AC_ERR_DEV) {
3278 		if (!ign_dev_err)
3279 			goto fail;
3280 		else
3281 			dev_err_whine = " (device error ignored)";
3282 	}
3283 
3284 	DPRINTK("xfer_shift=%u, xfer_mode=0x%x\n",
3285 		dev->xfer_shift, (int)dev->xfer_mode);
3286 
3287 	ata_dev_info(dev, "configured for %s%s\n",
3288 		     ata_mode_string(ata_xfer_mode2mask(dev->xfer_mode)),
3289 		     dev_err_whine);
3290 
3291 	return 0;
3292 
3293  fail:
3294 	ata_dev_err(dev, "failed to set xfermode (err_mask=0x%x)\n", err_mask);
3295 	return -EIO;
3296 }
3297 
3298 /**
3299  *	ata_do_set_mode - Program timings and issue SET FEATURES - XFER
3300  *	@link: link on which timings will be programmed
3301  *	@r_failed_dev: out parameter for failed device
3302  *
3303  *	Standard implementation of the function used to tune and set
3304  *	ATA device disk transfer mode (PIO3, UDMA6, etc.).  If
3305  *	ata_dev_set_mode() fails, pointer to the failing device is
3306  *	returned in @r_failed_dev.
3307  *
3308  *	LOCKING:
3309  *	PCI/etc. bus probe sem.
3310  *
3311  *	RETURNS:
3312  *	0 on success, negative errno otherwise
3313  */
3314 
3315 int ata_do_set_mode(struct ata_link *link, struct ata_device **r_failed_dev)
3316 {
3317 	struct ata_port *ap = link->ap;
3318 	struct ata_device *dev;
3319 	int rc = 0, used_dma = 0, found = 0;
3320 
3321 	/* step 1: calculate xfer_mask */
3322 	ata_for_each_dev(dev, link, ENABLED) {
3323 		unsigned long pio_mask, dma_mask;
3324 		unsigned int mode_mask;
3325 
3326 		mode_mask = ATA_DMA_MASK_ATA;
3327 		if (dev->class == ATA_DEV_ATAPI)
3328 			mode_mask = ATA_DMA_MASK_ATAPI;
3329 		else if (ata_id_is_cfa(dev->id))
3330 			mode_mask = ATA_DMA_MASK_CFA;
3331 
3332 		ata_dev_xfermask(dev);
3333 		ata_force_xfermask(dev);
3334 
3335 		pio_mask = ata_pack_xfermask(dev->pio_mask, 0, 0);
3336 
3337 		if (libata_dma_mask & mode_mask)
3338 			dma_mask = ata_pack_xfermask(0, dev->mwdma_mask,
3339 						     dev->udma_mask);
3340 		else
3341 			dma_mask = 0;
3342 
3343 		dev->pio_mode = ata_xfer_mask2mode(pio_mask);
3344 		dev->dma_mode = ata_xfer_mask2mode(dma_mask);
3345 
3346 		found = 1;
3347 		if (ata_dma_enabled(dev))
3348 			used_dma = 1;
3349 	}
3350 	if (!found)
3351 		goto out;
3352 
3353 	/* step 2: always set host PIO timings */
3354 	ata_for_each_dev(dev, link, ENABLED) {
3355 		if (dev->pio_mode == 0xff) {
3356 			ata_dev_warn(dev, "no PIO support\n");
3357 			rc = -EINVAL;
3358 			goto out;
3359 		}
3360 
3361 		dev->xfer_mode = dev->pio_mode;
3362 		dev->xfer_shift = ATA_SHIFT_PIO;
3363 		if (ap->ops->set_piomode)
3364 			ap->ops->set_piomode(ap, dev);
3365 	}
3366 
3367 	/* step 3: set host DMA timings */
3368 	ata_for_each_dev(dev, link, ENABLED) {
3369 		if (!ata_dma_enabled(dev))
3370 			continue;
3371 
3372 		dev->xfer_mode = dev->dma_mode;
3373 		dev->xfer_shift = ata_xfer_mode2shift(dev->dma_mode);
3374 		if (ap->ops->set_dmamode)
3375 			ap->ops->set_dmamode(ap, dev);
3376 	}
3377 
3378 	/* step 4: update devices' xfer mode */
3379 	ata_for_each_dev(dev, link, ENABLED) {
3380 		rc = ata_dev_set_mode(dev);
3381 		if (rc)
3382 			goto out;
3383 	}
3384 
3385 	/* Record simplex status. If we selected DMA then the other
3386 	 * host channels are not permitted to do so.
3387 	 */
3388 	if (used_dma && (ap->host->flags & ATA_HOST_SIMPLEX))
3389 		ap->host->simplex_claimed = ap;
3390 
3391  out:
3392 	if (rc)
3393 		*r_failed_dev = dev;
3394 	return rc;
3395 }
3396 
3397 /**
3398  *	ata_wait_ready - wait for link to become ready
3399  *	@link: link to be waited on
3400  *	@deadline: deadline jiffies for the operation
3401  *	@check_ready: callback to check link readiness
3402  *
3403  *	Wait for @link to become ready.  @check_ready should return
3404  *	positive number if @link is ready, 0 if it isn't, -ENODEV if
3405  *	link doesn't seem to be occupied, other errno for other error
3406  *	conditions.
3407  *
3408  *	Transient -ENODEV conditions are allowed for
3409  *	ATA_TMOUT_FF_WAIT.
3410  *
3411  *	LOCKING:
3412  *	EH context.
3413  *
3414  *	RETURNS:
3415  *	0 if @linke is ready before @deadline; otherwise, -errno.
3416  */
3417 int ata_wait_ready(struct ata_link *link, unsigned long deadline,
3418 		   int (*check_ready)(struct ata_link *link))
3419 {
3420 	unsigned long start = jiffies;
3421 	unsigned long nodev_deadline;
3422 	int warned = 0;
3423 
3424 	/* choose which 0xff timeout to use, read comment in libata.h */
3425 	if (link->ap->host->flags & ATA_HOST_PARALLEL_SCAN)
3426 		nodev_deadline = ata_deadline(start, ATA_TMOUT_FF_WAIT_LONG);
3427 	else
3428 		nodev_deadline = ata_deadline(start, ATA_TMOUT_FF_WAIT);
3429 
3430 	/* Slave readiness can't be tested separately from master.  On
3431 	 * M/S emulation configuration, this function should be called
3432 	 * only on the master and it will handle both master and slave.
3433 	 */
3434 	WARN_ON(link == link->ap->slave_link);
3435 
3436 	if (time_after(nodev_deadline, deadline))
3437 		nodev_deadline = deadline;
3438 
3439 	while (1) {
3440 		unsigned long now = jiffies;
3441 		int ready, tmp;
3442 
3443 		ready = tmp = check_ready(link);
3444 		if (ready > 0)
3445 			return 0;
3446 
3447 		/*
3448 		 * -ENODEV could be transient.  Ignore -ENODEV if link
3449 		 * is online.  Also, some SATA devices take a long
3450 		 * time to clear 0xff after reset.  Wait for
3451 		 * ATA_TMOUT_FF_WAIT[_LONG] on -ENODEV if link isn't
3452 		 * offline.
3453 		 *
3454 		 * Note that some PATA controllers (pata_ali) explode
3455 		 * if status register is read more than once when
3456 		 * there's no device attached.
3457 		 */
3458 		if (ready == -ENODEV) {
3459 			if (ata_link_online(link))
3460 				ready = 0;
3461 			else if ((link->ap->flags & ATA_FLAG_SATA) &&
3462 				 !ata_link_offline(link) &&
3463 				 time_before(now, nodev_deadline))
3464 				ready = 0;
3465 		}
3466 
3467 		if (ready)
3468 			return ready;
3469 		if (time_after(now, deadline))
3470 			return -EBUSY;
3471 
3472 		if (!warned && time_after(now, start + 5 * HZ) &&
3473 		    (deadline - now > 3 * HZ)) {
3474 			ata_link_warn(link,
3475 				"link is slow to respond, please be patient "
3476 				"(ready=%d)\n", tmp);
3477 			warned = 1;
3478 		}
3479 
3480 		ata_msleep(link->ap, 50);
3481 	}
3482 }
3483 
3484 /**
3485  *	ata_wait_after_reset - wait for link to become ready after reset
3486  *	@link: link to be waited on
3487  *	@deadline: deadline jiffies for the operation
3488  *	@check_ready: callback to check link readiness
3489  *
3490  *	Wait for @link to become ready after reset.
3491  *
3492  *	LOCKING:
3493  *	EH context.
3494  *
3495  *	RETURNS:
3496  *	0 if @linke is ready before @deadline; otherwise, -errno.
3497  */
3498 int ata_wait_after_reset(struct ata_link *link, unsigned long deadline,
3499 				int (*check_ready)(struct ata_link *link))
3500 {
3501 	ata_msleep(link->ap, ATA_WAIT_AFTER_RESET);
3502 
3503 	return ata_wait_ready(link, deadline, check_ready);
3504 }
3505 
3506 /**
3507  *	sata_link_debounce - debounce SATA phy status
3508  *	@link: ATA link to debounce SATA phy status for
3509  *	@params: timing parameters { interval, duratinon, timeout } in msec
3510  *	@deadline: deadline jiffies for the operation
3511  *
3512  *	Make sure SStatus of @link reaches stable state, determined by
3513  *	holding the same value where DET is not 1 for @duration polled
3514  *	every @interval, before @timeout.  Timeout constraints the
3515  *	beginning of the stable state.  Because DET gets stuck at 1 on
3516  *	some controllers after hot unplugging, this functions waits
3517  *	until timeout then returns 0 if DET is stable at 1.
3518  *
3519  *	@timeout is further limited by @deadline.  The sooner of the
3520  *	two is used.
3521  *
3522  *	LOCKING:
3523  *	Kernel thread context (may sleep)
3524  *
3525  *	RETURNS:
3526  *	0 on success, -errno on failure.
3527  */
3528 int sata_link_debounce(struct ata_link *link, const unsigned long *params,
3529 		       unsigned long deadline)
3530 {
3531 	unsigned long interval = params[0];
3532 	unsigned long duration = params[1];
3533 	unsigned long last_jiffies, t;
3534 	u32 last, cur;
3535 	int rc;
3536 
3537 	t = ata_deadline(jiffies, params[2]);
3538 	if (time_before(t, deadline))
3539 		deadline = t;
3540 
3541 	if ((rc = sata_scr_read(link, SCR_STATUS, &cur)))
3542 		return rc;
3543 	cur &= 0xf;
3544 
3545 	last = cur;
3546 	last_jiffies = jiffies;
3547 
3548 	while (1) {
3549 		ata_msleep(link->ap, interval);
3550 		if ((rc = sata_scr_read(link, SCR_STATUS, &cur)))
3551 			return rc;
3552 		cur &= 0xf;
3553 
3554 		/* DET stable? */
3555 		if (cur == last) {
3556 			if (cur == 1 && time_before(jiffies, deadline))
3557 				continue;
3558 			if (time_after(jiffies,
3559 				       ata_deadline(last_jiffies, duration)))
3560 				return 0;
3561 			continue;
3562 		}
3563 
3564 		/* unstable, start over */
3565 		last = cur;
3566 		last_jiffies = jiffies;
3567 
3568 		/* Check deadline.  If debouncing failed, return
3569 		 * -EPIPE to tell upper layer to lower link speed.
3570 		 */
3571 		if (time_after(jiffies, deadline))
3572 			return -EPIPE;
3573 	}
3574 }
3575 
3576 /**
3577  *	sata_link_resume - resume SATA link
3578  *	@link: ATA link to resume SATA
3579  *	@params: timing parameters { interval, duratinon, timeout } in msec
3580  *	@deadline: deadline jiffies for the operation
3581  *
3582  *	Resume SATA phy @link and debounce it.
3583  *
3584  *	LOCKING:
3585  *	Kernel thread context (may sleep)
3586  *
3587  *	RETURNS:
3588  *	0 on success, -errno on failure.
3589  */
3590 int sata_link_resume(struct ata_link *link, const unsigned long *params,
3591 		     unsigned long deadline)
3592 {
3593 	int tries = ATA_LINK_RESUME_TRIES;
3594 	u32 scontrol, serror;
3595 	int rc;
3596 
3597 	if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3598 		return rc;
3599 
3600 	/*
3601 	 * Writes to SControl sometimes get ignored under certain
3602 	 * controllers (ata_piix SIDPR).  Make sure DET actually is
3603 	 * cleared.
3604 	 */
3605 	do {
3606 		scontrol = (scontrol & 0x0f0) | 0x300;
3607 		if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
3608 			return rc;
3609 		/*
3610 		 * Some PHYs react badly if SStatus is pounded
3611 		 * immediately after resuming.  Delay 200ms before
3612 		 * debouncing.
3613 		 */
3614 		ata_msleep(link->ap, 200);
3615 
3616 		/* is SControl restored correctly? */
3617 		if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3618 			return rc;
3619 	} while ((scontrol & 0xf0f) != 0x300 && --tries);
3620 
3621 	if ((scontrol & 0xf0f) != 0x300) {
3622 		ata_link_warn(link, "failed to resume link (SControl %X)\n",
3623 			     scontrol);
3624 		return 0;
3625 	}
3626 
3627 	if (tries < ATA_LINK_RESUME_TRIES)
3628 		ata_link_warn(link, "link resume succeeded after %d retries\n",
3629 			      ATA_LINK_RESUME_TRIES - tries);
3630 
3631 	if ((rc = sata_link_debounce(link, params, deadline)))
3632 		return rc;
3633 
3634 	/* clear SError, some PHYs require this even for SRST to work */
3635 	if (!(rc = sata_scr_read(link, SCR_ERROR, &serror)))
3636 		rc = sata_scr_write(link, SCR_ERROR, serror);
3637 
3638 	return rc != -EINVAL ? rc : 0;
3639 }
3640 
3641 /**
3642  *	sata_link_scr_lpm - manipulate SControl IPM and SPM fields
3643  *	@link: ATA link to manipulate SControl for
3644  *	@policy: LPM policy to configure
3645  *	@spm_wakeup: initiate LPM transition to active state
3646  *
3647  *	Manipulate the IPM field of the SControl register of @link
3648  *	according to @policy.  If @policy is ATA_LPM_MAX_POWER and
3649  *	@spm_wakeup is %true, the SPM field is manipulated to wake up
3650  *	the link.  This function also clears PHYRDY_CHG before
3651  *	returning.
3652  *
3653  *	LOCKING:
3654  *	EH context.
3655  *
3656  *	RETURNS:
3657  *	0 on succes, -errno otherwise.
3658  */
3659 int sata_link_scr_lpm(struct ata_link *link, enum ata_lpm_policy policy,
3660 		      bool spm_wakeup)
3661 {
3662 	struct ata_eh_context *ehc = &link->eh_context;
3663 	bool woken_up = false;
3664 	u32 scontrol;
3665 	int rc;
3666 
3667 	rc = sata_scr_read(link, SCR_CONTROL, &scontrol);
3668 	if (rc)
3669 		return rc;
3670 
3671 	switch (policy) {
3672 	case ATA_LPM_MAX_POWER:
3673 		/* disable all LPM transitions */
3674 		scontrol |= (0x7 << 8);
3675 		/* initiate transition to active state */
3676 		if (spm_wakeup) {
3677 			scontrol |= (0x4 << 12);
3678 			woken_up = true;
3679 		}
3680 		break;
3681 	case ATA_LPM_MED_POWER:
3682 		/* allow LPM to PARTIAL */
3683 		scontrol &= ~(0x1 << 8);
3684 		scontrol |= (0x6 << 8);
3685 		break;
3686 	case ATA_LPM_MIN_POWER:
3687 		if (ata_link_nr_enabled(link) > 0)
3688 			/* no restrictions on LPM transitions */
3689 			scontrol &= ~(0x7 << 8);
3690 		else {
3691 			/* empty port, power off */
3692 			scontrol &= ~0xf;
3693 			scontrol |= (0x1 << 2);
3694 		}
3695 		break;
3696 	default:
3697 		WARN_ON(1);
3698 	}
3699 
3700 	rc = sata_scr_write(link, SCR_CONTROL, scontrol);
3701 	if (rc)
3702 		return rc;
3703 
3704 	/* give the link time to transit out of LPM state */
3705 	if (woken_up)
3706 		msleep(10);
3707 
3708 	/* clear PHYRDY_CHG from SError */
3709 	ehc->i.serror &= ~SERR_PHYRDY_CHG;
3710 	return sata_scr_write(link, SCR_ERROR, SERR_PHYRDY_CHG);
3711 }
3712 
3713 /**
3714  *	ata_std_prereset - prepare for reset
3715  *	@link: ATA link to be reset
3716  *	@deadline: deadline jiffies for the operation
3717  *
3718  *	@link is about to be reset.  Initialize it.  Failure from
3719  *	prereset makes libata abort whole reset sequence and give up
3720  *	that port, so prereset should be best-effort.  It does its
3721  *	best to prepare for reset sequence but if things go wrong, it
3722  *	should just whine, not fail.
3723  *
3724  *	LOCKING:
3725  *	Kernel thread context (may sleep)
3726  *
3727  *	RETURNS:
3728  *	0 on success, -errno otherwise.
3729  */
3730 int ata_std_prereset(struct ata_link *link, unsigned long deadline)
3731 {
3732 	struct ata_port *ap = link->ap;
3733 	struct ata_eh_context *ehc = &link->eh_context;
3734 	const unsigned long *timing = sata_ehc_deb_timing(ehc);
3735 	int rc;
3736 
3737 	/* if we're about to do hardreset, nothing more to do */
3738 	if (ehc->i.action & ATA_EH_HARDRESET)
3739 		return 0;
3740 
3741 	/* if SATA, resume link */
3742 	if (ap->flags & ATA_FLAG_SATA) {
3743 		rc = sata_link_resume(link, timing, deadline);
3744 		/* whine about phy resume failure but proceed */
3745 		if (rc && rc != -EOPNOTSUPP)
3746 			ata_link_warn(link,
3747 				      "failed to resume link for reset (errno=%d)\n",
3748 				      rc);
3749 	}
3750 
3751 	/* no point in trying softreset on offline link */
3752 	if (ata_phys_link_offline(link))
3753 		ehc->i.action &= ~ATA_EH_SOFTRESET;
3754 
3755 	return 0;
3756 }
3757 
3758 /**
3759  *	sata_link_hardreset - reset link via SATA phy reset
3760  *	@link: link to reset
3761  *	@timing: timing parameters { interval, duratinon, timeout } in msec
3762  *	@deadline: deadline jiffies for the operation
3763  *	@online: optional out parameter indicating link onlineness
3764  *	@check_ready: optional callback to check link readiness
3765  *
3766  *	SATA phy-reset @link using DET bits of SControl register.
3767  *	After hardreset, link readiness is waited upon using
3768  *	ata_wait_ready() if @check_ready is specified.  LLDs are
3769  *	allowed to not specify @check_ready and wait itself after this
3770  *	function returns.  Device classification is LLD's
3771  *	responsibility.
3772  *
3773  *	*@online is set to one iff reset succeeded and @link is online
3774  *	after reset.
3775  *
3776  *	LOCKING:
3777  *	Kernel thread context (may sleep)
3778  *
3779  *	RETURNS:
3780  *	0 on success, -errno otherwise.
3781  */
3782 int sata_link_hardreset(struct ata_link *link, const unsigned long *timing,
3783 			unsigned long deadline,
3784 			bool *online, int (*check_ready)(struct ata_link *))
3785 {
3786 	u32 scontrol;
3787 	int rc;
3788 
3789 	DPRINTK("ENTER\n");
3790 
3791 	if (online)
3792 		*online = false;
3793 
3794 	if (sata_set_spd_needed(link)) {
3795 		/* SATA spec says nothing about how to reconfigure
3796 		 * spd.  To be on the safe side, turn off phy during
3797 		 * reconfiguration.  This works for at least ICH7 AHCI
3798 		 * and Sil3124.
3799 		 */
3800 		if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3801 			goto out;
3802 
3803 		scontrol = (scontrol & 0x0f0) | 0x304;
3804 
3805 		if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
3806 			goto out;
3807 
3808 		sata_set_spd(link);
3809 	}
3810 
3811 	/* issue phy wake/reset */
3812 	if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3813 		goto out;
3814 
3815 	scontrol = (scontrol & 0x0f0) | 0x301;
3816 
3817 	if ((rc = sata_scr_write_flush(link, SCR_CONTROL, scontrol)))
3818 		goto out;
3819 
3820 	/* Couldn't find anything in SATA I/II specs, but AHCI-1.1
3821 	 * 10.4.2 says at least 1 ms.
3822 	 */
3823 	ata_msleep(link->ap, 1);
3824 
3825 	/* bring link back */
3826 	rc = sata_link_resume(link, timing, deadline);
3827 	if (rc)
3828 		goto out;
3829 	/* if link is offline nothing more to do */
3830 	if (ata_phys_link_offline(link))
3831 		goto out;
3832 
3833 	/* Link is online.  From this point, -ENODEV too is an error. */
3834 	if (online)
3835 		*online = true;
3836 
3837 	if (sata_pmp_supported(link->ap) && ata_is_host_link(link)) {
3838 		/* If PMP is supported, we have to do follow-up SRST.
3839 		 * Some PMPs don't send D2H Reg FIS after hardreset if
3840 		 * the first port is empty.  Wait only for
3841 		 * ATA_TMOUT_PMP_SRST_WAIT.
3842 		 */
3843 		if (check_ready) {
3844 			unsigned long pmp_deadline;
3845 
3846 			pmp_deadline = ata_deadline(jiffies,
3847 						    ATA_TMOUT_PMP_SRST_WAIT);
3848 			if (time_after(pmp_deadline, deadline))
3849 				pmp_deadline = deadline;
3850 			ata_wait_ready(link, pmp_deadline, check_ready);
3851 		}
3852 		rc = -EAGAIN;
3853 		goto out;
3854 	}
3855 
3856 	rc = 0;
3857 	if (check_ready)
3858 		rc = ata_wait_ready(link, deadline, check_ready);
3859  out:
3860 	if (rc && rc != -EAGAIN) {
3861 		/* online is set iff link is online && reset succeeded */
3862 		if (online)
3863 			*online = false;
3864 		ata_link_err(link, "COMRESET failed (errno=%d)\n", rc);
3865 	}
3866 	DPRINTK("EXIT, rc=%d\n", rc);
3867 	return rc;
3868 }
3869 
3870 /**
3871  *	sata_std_hardreset - COMRESET w/o waiting or classification
3872  *	@link: link to reset
3873  *	@class: resulting class of attached device
3874  *	@deadline: deadline jiffies for the operation
3875  *
3876  *	Standard SATA COMRESET w/o waiting or classification.
3877  *
3878  *	LOCKING:
3879  *	Kernel thread context (may sleep)
3880  *
3881  *	RETURNS:
3882  *	0 if link offline, -EAGAIN if link online, -errno on errors.
3883  */
3884 int sata_std_hardreset(struct ata_link *link, unsigned int *class,
3885 		       unsigned long deadline)
3886 {
3887 	const unsigned long *timing = sata_ehc_deb_timing(&link->eh_context);
3888 	bool online;
3889 	int rc;
3890 
3891 	/* do hardreset */
3892 	rc = sata_link_hardreset(link, timing, deadline, &online, NULL);
3893 	return online ? -EAGAIN : rc;
3894 }
3895 
3896 /**
3897  *	ata_std_postreset - standard postreset callback
3898  *	@link: the target ata_link
3899  *	@classes: classes of attached devices
3900  *
3901  *	This function is invoked after a successful reset.  Note that
3902  *	the device might have been reset more than once using
3903  *	different reset methods before postreset is invoked.
3904  *
3905  *	LOCKING:
3906  *	Kernel thread context (may sleep)
3907  */
3908 void ata_std_postreset(struct ata_link *link, unsigned int *classes)
3909 {
3910 	u32 serror;
3911 
3912 	DPRINTK("ENTER\n");
3913 
3914 	/* reset complete, clear SError */
3915 	if (!sata_scr_read(link, SCR_ERROR, &serror))
3916 		sata_scr_write(link, SCR_ERROR, serror);
3917 
3918 	/* print link status */
3919 	sata_print_link_status(link);
3920 
3921 	DPRINTK("EXIT\n");
3922 }
3923 
3924 /**
3925  *	ata_dev_same_device - Determine whether new ID matches configured device
3926  *	@dev: device to compare against
3927  *	@new_class: class of the new device
3928  *	@new_id: IDENTIFY page of the new device
3929  *
3930  *	Compare @new_class and @new_id against @dev and determine
3931  *	whether @dev is the device indicated by @new_class and
3932  *	@new_id.
3933  *
3934  *	LOCKING:
3935  *	None.
3936  *
3937  *	RETURNS:
3938  *	1 if @dev matches @new_class and @new_id, 0 otherwise.
3939  */
3940 static int ata_dev_same_device(struct ata_device *dev, unsigned int new_class,
3941 			       const u16 *new_id)
3942 {
3943 	const u16 *old_id = dev->id;
3944 	unsigned char model[2][ATA_ID_PROD_LEN + 1];
3945 	unsigned char serial[2][ATA_ID_SERNO_LEN + 1];
3946 
3947 	if (dev->class != new_class) {
3948 		ata_dev_info(dev, "class mismatch %d != %d\n",
3949 			     dev->class, new_class);
3950 		return 0;
3951 	}
3952 
3953 	ata_id_c_string(old_id, model[0], ATA_ID_PROD, sizeof(model[0]));
3954 	ata_id_c_string(new_id, model[1], ATA_ID_PROD, sizeof(model[1]));
3955 	ata_id_c_string(old_id, serial[0], ATA_ID_SERNO, sizeof(serial[0]));
3956 	ata_id_c_string(new_id, serial[1], ATA_ID_SERNO, sizeof(serial[1]));
3957 
3958 	if (strcmp(model[0], model[1])) {
3959 		ata_dev_info(dev, "model number mismatch '%s' != '%s'\n",
3960 			     model[0], model[1]);
3961 		return 0;
3962 	}
3963 
3964 	if (strcmp(serial[0], serial[1])) {
3965 		ata_dev_info(dev, "serial number mismatch '%s' != '%s'\n",
3966 			     serial[0], serial[1]);
3967 		return 0;
3968 	}
3969 
3970 	return 1;
3971 }
3972 
3973 /**
3974  *	ata_dev_reread_id - Re-read IDENTIFY data
3975  *	@dev: target ATA device
3976  *	@readid_flags: read ID flags
3977  *
3978  *	Re-read IDENTIFY page and make sure @dev is still attached to
3979  *	the port.
3980  *
3981  *	LOCKING:
3982  *	Kernel thread context (may sleep)
3983  *
3984  *	RETURNS:
3985  *	0 on success, negative errno otherwise
3986  */
3987 int ata_dev_reread_id(struct ata_device *dev, unsigned int readid_flags)
3988 {
3989 	unsigned int class = dev->class;
3990 	u16 *id = (void *)dev->link->ap->sector_buf;
3991 	int rc;
3992 
3993 	/* read ID data */
3994 	rc = ata_dev_read_id(dev, &class, readid_flags, id);
3995 	if (rc)
3996 		return rc;
3997 
3998 	/* is the device still there? */
3999 	if (!ata_dev_same_device(dev, class, id))
4000 		return -ENODEV;
4001 
4002 	memcpy(dev->id, id, sizeof(id[0]) * ATA_ID_WORDS);
4003 	return 0;
4004 }
4005 
4006 /**
4007  *	ata_dev_revalidate - Revalidate ATA device
4008  *	@dev: device to revalidate
4009  *	@new_class: new class code
4010  *	@readid_flags: read ID flags
4011  *
4012  *	Re-read IDENTIFY page, make sure @dev is still attached to the
4013  *	port and reconfigure it according to the new IDENTIFY page.
4014  *
4015  *	LOCKING:
4016  *	Kernel thread context (may sleep)
4017  *
4018  *	RETURNS:
4019  *	0 on success, negative errno otherwise
4020  */
4021 int ata_dev_revalidate(struct ata_device *dev, unsigned int new_class,
4022 		       unsigned int readid_flags)
4023 {
4024 	u64 n_sectors = dev->n_sectors;
4025 	u64 n_native_sectors = dev->n_native_sectors;
4026 	int rc;
4027 
4028 	if (!ata_dev_enabled(dev))
4029 		return -ENODEV;
4030 
4031 	/* fail early if !ATA && !ATAPI to avoid issuing [P]IDENTIFY to PMP */
4032 	if (ata_class_enabled(new_class) &&
4033 	    new_class != ATA_DEV_ATA &&
4034 	    new_class != ATA_DEV_ATAPI &&
4035 	    new_class != ATA_DEV_SEMB) {
4036 		ata_dev_info(dev, "class mismatch %u != %u\n",
4037 			     dev->class, new_class);
4038 		rc = -ENODEV;
4039 		goto fail;
4040 	}
4041 
4042 	/* re-read ID */
4043 	rc = ata_dev_reread_id(dev, readid_flags);
4044 	if (rc)
4045 		goto fail;
4046 
4047 	/* configure device according to the new ID */
4048 	rc = ata_dev_configure(dev);
4049 	if (rc)
4050 		goto fail;
4051 
4052 	/* verify n_sectors hasn't changed */
4053 	if (dev->class != ATA_DEV_ATA || !n_sectors ||
4054 	    dev->n_sectors == n_sectors)
4055 		return 0;
4056 
4057 	/* n_sectors has changed */
4058 	ata_dev_warn(dev, "n_sectors mismatch %llu != %llu\n",
4059 		     (unsigned long long)n_sectors,
4060 		     (unsigned long long)dev->n_sectors);
4061 
4062 	/*
4063 	 * Something could have caused HPA to be unlocked
4064 	 * involuntarily.  If n_native_sectors hasn't changed and the
4065 	 * new size matches it, keep the device.
4066 	 */
4067 	if (dev->n_native_sectors == n_native_sectors &&
4068 	    dev->n_sectors > n_sectors && dev->n_sectors == n_native_sectors) {
4069 		ata_dev_warn(dev,
4070 			     "new n_sectors matches native, probably "
4071 			     "late HPA unlock, n_sectors updated\n");
4072 		/* use the larger n_sectors */
4073 		return 0;
4074 	}
4075 
4076 	/*
4077 	 * Some BIOSes boot w/o HPA but resume w/ HPA locked.  Try
4078 	 * unlocking HPA in those cases.
4079 	 *
4080 	 * https://bugzilla.kernel.org/show_bug.cgi?id=15396
4081 	 */
4082 	if (dev->n_native_sectors == n_native_sectors &&
4083 	    dev->n_sectors < n_sectors && n_sectors == n_native_sectors &&
4084 	    !(dev->horkage & ATA_HORKAGE_BROKEN_HPA)) {
4085 		ata_dev_warn(dev,
4086 			     "old n_sectors matches native, probably "
4087 			     "late HPA lock, will try to unlock HPA\n");
4088 		/* try unlocking HPA */
4089 		dev->flags |= ATA_DFLAG_UNLOCK_HPA;
4090 		rc = -EIO;
4091 	} else
4092 		rc = -ENODEV;
4093 
4094 	/* restore original n_[native_]sectors and fail */
4095 	dev->n_native_sectors = n_native_sectors;
4096 	dev->n_sectors = n_sectors;
4097  fail:
4098 	ata_dev_err(dev, "revalidation failed (errno=%d)\n", rc);
4099 	return rc;
4100 }
4101 
4102 struct ata_blacklist_entry {
4103 	const char *model_num;
4104 	const char *model_rev;
4105 	unsigned long horkage;
4106 };
4107 
4108 static const struct ata_blacklist_entry ata_device_blacklist [] = {
4109 	/* Devices with DMA related problems under Linux */
4110 	{ "WDC AC11000H",	NULL,		ATA_HORKAGE_NODMA },
4111 	{ "WDC AC22100H",	NULL,		ATA_HORKAGE_NODMA },
4112 	{ "WDC AC32500H",	NULL,		ATA_HORKAGE_NODMA },
4113 	{ "WDC AC33100H",	NULL,		ATA_HORKAGE_NODMA },
4114 	{ "WDC AC31600H",	NULL,		ATA_HORKAGE_NODMA },
4115 	{ "WDC AC32100H",	"24.09P07",	ATA_HORKAGE_NODMA },
4116 	{ "WDC AC23200L",	"21.10N21",	ATA_HORKAGE_NODMA },
4117 	{ "Compaq CRD-8241B", 	NULL,		ATA_HORKAGE_NODMA },
4118 	{ "CRD-8400B",		NULL, 		ATA_HORKAGE_NODMA },
4119 	{ "CRD-848[02]B",	NULL,		ATA_HORKAGE_NODMA },
4120 	{ "CRD-84",		NULL,		ATA_HORKAGE_NODMA },
4121 	{ "SanDisk SDP3B",	NULL,		ATA_HORKAGE_NODMA },
4122 	{ "SanDisk SDP3B-64",	NULL,		ATA_HORKAGE_NODMA },
4123 	{ "SANYO CD-ROM CRD",	NULL,		ATA_HORKAGE_NODMA },
4124 	{ "HITACHI CDR-8",	NULL,		ATA_HORKAGE_NODMA },
4125 	{ "HITACHI CDR-8[34]35",NULL,		ATA_HORKAGE_NODMA },
4126 	{ "Toshiba CD-ROM XM-6202B", NULL,	ATA_HORKAGE_NODMA },
4127 	{ "TOSHIBA CD-ROM XM-1702BC", NULL,	ATA_HORKAGE_NODMA },
4128 	{ "CD-532E-A", 		NULL,		ATA_HORKAGE_NODMA },
4129 	{ "E-IDE CD-ROM CR-840",NULL,		ATA_HORKAGE_NODMA },
4130 	{ "CD-ROM Drive/F5A",	NULL,		ATA_HORKAGE_NODMA },
4131 	{ "WPI CDD-820", 	NULL,		ATA_HORKAGE_NODMA },
4132 	{ "SAMSUNG CD-ROM SC-148C", NULL,	ATA_HORKAGE_NODMA },
4133 	{ "SAMSUNG CD-ROM SC",	NULL,		ATA_HORKAGE_NODMA },
4134 	{ "ATAPI CD-ROM DRIVE 40X MAXIMUM",NULL,ATA_HORKAGE_NODMA },
4135 	{ "_NEC DV5800A", 	NULL,		ATA_HORKAGE_NODMA },
4136 	{ "SAMSUNG CD-ROM SN-124", "N001",	ATA_HORKAGE_NODMA },
4137 	{ "Seagate STT20000A", NULL,		ATA_HORKAGE_NODMA },
4138 	{ " 2GB ATA Flash Disk", "ADMA428M",	ATA_HORKAGE_NODMA },
4139 	/* Odd clown on sil3726/4726 PMPs */
4140 	{ "Config  Disk",	NULL,		ATA_HORKAGE_DISABLE },
4141 
4142 	/* Weird ATAPI devices */
4143 	{ "TORiSAN DVD-ROM DRD-N216", NULL,	ATA_HORKAGE_MAX_SEC_128 },
4144 	{ "QUANTUM DAT    DAT72-000", NULL,	ATA_HORKAGE_ATAPI_MOD16_DMA },
4145 	{ "Slimtype DVD A  DS8A8SH", NULL,	ATA_HORKAGE_MAX_SEC_LBA48 },
4146 	{ "Slimtype DVD A  DS8A9SH", NULL,	ATA_HORKAGE_MAX_SEC_LBA48 },
4147 
4148 	/* Devices we expect to fail diagnostics */
4149 
4150 	/* Devices where NCQ should be avoided */
4151 	/* NCQ is slow */
4152 	{ "WDC WD740ADFD-00",	NULL,		ATA_HORKAGE_NONCQ },
4153 	{ "WDC WD740ADFD-00NLR1", NULL,		ATA_HORKAGE_NONCQ, },
4154 	/* http://thread.gmane.org/gmane.linux.ide/14907 */
4155 	{ "FUJITSU MHT2060BH",	NULL,		ATA_HORKAGE_NONCQ },
4156 	/* NCQ is broken */
4157 	{ "Maxtor *",		"BANC*",	ATA_HORKAGE_NONCQ },
4158 	{ "Maxtor 7V300F0",	"VA111630",	ATA_HORKAGE_NONCQ },
4159 	{ "ST380817AS",		"3.42",		ATA_HORKAGE_NONCQ },
4160 	{ "ST3160023AS",	"3.42",		ATA_HORKAGE_NONCQ },
4161 	{ "OCZ CORE_SSD",	"02.10104",	ATA_HORKAGE_NONCQ },
4162 
4163 	/* Seagate NCQ + FLUSH CACHE firmware bug */
4164 	{ "ST31500341AS",	"SD1[5-9]",	ATA_HORKAGE_NONCQ |
4165 						ATA_HORKAGE_FIRMWARE_WARN },
4166 
4167 	{ "ST31000333AS",	"SD1[5-9]",	ATA_HORKAGE_NONCQ |
4168 						ATA_HORKAGE_FIRMWARE_WARN },
4169 
4170 	{ "ST3640[36]23AS",	"SD1[5-9]",	ATA_HORKAGE_NONCQ |
4171 						ATA_HORKAGE_FIRMWARE_WARN },
4172 
4173 	{ "ST3320[68]13AS",	"SD1[5-9]",	ATA_HORKAGE_NONCQ |
4174 						ATA_HORKAGE_FIRMWARE_WARN },
4175 
4176 	/* Seagate Momentus SpinPoint M8 seem to have FPMDA_AA issues */
4177 	{ "ST1000LM024 HN-M101MBB", "2AR10001",	ATA_HORKAGE_BROKEN_FPDMA_AA },
4178 	{ "ST1000LM024 HN-M101MBB", "2BA30001",	ATA_HORKAGE_BROKEN_FPDMA_AA },
4179 
4180 	/* Blacklist entries taken from Silicon Image 3124/3132
4181 	   Windows driver .inf file - also several Linux problem reports */
4182 	{ "HTS541060G9SA00",    "MB3OC60D",     ATA_HORKAGE_NONCQ, },
4183 	{ "HTS541080G9SA00",    "MB4OC60D",     ATA_HORKAGE_NONCQ, },
4184 	{ "HTS541010G9SA00",    "MBZOC60D",     ATA_HORKAGE_NONCQ, },
4185 
4186 	/* https://bugzilla.kernel.org/show_bug.cgi?id=15573 */
4187 	{ "C300-CTFDDAC128MAG",	"0001",		ATA_HORKAGE_NONCQ, },
4188 
4189 	/* devices which puke on READ_NATIVE_MAX */
4190 	{ "HDS724040KLSA80",	"KFAOA20N",	ATA_HORKAGE_BROKEN_HPA, },
4191 	{ "WDC WD3200JD-00KLB0", "WD-WCAMR1130137", ATA_HORKAGE_BROKEN_HPA },
4192 	{ "WDC WD2500JD-00HBB0", "WD-WMAL71490727", ATA_HORKAGE_BROKEN_HPA },
4193 	{ "MAXTOR 6L080L4",	"A93.0500",	ATA_HORKAGE_BROKEN_HPA },
4194 
4195 	/* this one allows HPA unlocking but fails IOs on the area */
4196 	{ "OCZ-VERTEX",		    "1.30",	ATA_HORKAGE_BROKEN_HPA },
4197 
4198 	/* Devices which report 1 sector over size HPA */
4199 	{ "ST340823A",		NULL,		ATA_HORKAGE_HPA_SIZE, },
4200 	{ "ST320413A",		NULL,		ATA_HORKAGE_HPA_SIZE, },
4201 	{ "ST310211A",		NULL,		ATA_HORKAGE_HPA_SIZE, },
4202 
4203 	/* Devices which get the IVB wrong */
4204 	{ "QUANTUM FIREBALLlct10 05", "A03.0900", ATA_HORKAGE_IVB, },
4205 	/* Maybe we should just blacklist TSSTcorp... */
4206 	{ "TSSTcorp CDDVDW SH-S202[HJN]", "SB0[01]",  ATA_HORKAGE_IVB, },
4207 
4208 	/* Devices that do not need bridging limits applied */
4209 	{ "MTRON MSP-SATA*",		NULL,	ATA_HORKAGE_BRIDGE_OK, },
4210 	{ "BUFFALO HD-QSU2/R5",		NULL,	ATA_HORKAGE_BRIDGE_OK, },
4211 
4212 	/* Devices which aren't very happy with higher link speeds */
4213 	{ "WD My Book",			NULL,	ATA_HORKAGE_1_5_GBPS, },
4214 	{ "Seagate FreeAgent GoFlex",	NULL,	ATA_HORKAGE_1_5_GBPS, },
4215 
4216 	/*
4217 	 * Devices which choke on SETXFER.  Applies only if both the
4218 	 * device and controller are SATA.
4219 	 */
4220 	{ "PIONEER DVD-RW  DVRTD08",	NULL,	ATA_HORKAGE_NOSETXFER },
4221 	{ "PIONEER DVD-RW  DVRTD08A",	NULL,	ATA_HORKAGE_NOSETXFER },
4222 	{ "PIONEER DVD-RW  DVR-215",	NULL,	ATA_HORKAGE_NOSETXFER },
4223 	{ "PIONEER DVD-RW  DVR-212D",	NULL,	ATA_HORKAGE_NOSETXFER },
4224 	{ "PIONEER DVD-RW  DVR-216D",	NULL,	ATA_HORKAGE_NOSETXFER },
4225 
4226 	/* devices that don't properly handle queued TRIM commands */
4227 	{ "Micron_M500*",		NULL,	ATA_HORKAGE_NO_NCQ_TRIM, },
4228 	{ "Crucial_CT???M500SSD*",	NULL,	ATA_HORKAGE_NO_NCQ_TRIM, },
4229 	{ "Micron_M550*",		NULL,	ATA_HORKAGE_NO_NCQ_TRIM, },
4230 	{ "Crucial_CT???M550SSD*",	NULL,	ATA_HORKAGE_NO_NCQ_TRIM, },
4231 
4232 	/*
4233 	 * Some WD SATA-I drives spin up and down erratically when the link
4234 	 * is put into the slumber mode.  We don't have full list of the
4235 	 * affected devices.  Disable LPM if the device matches one of the
4236 	 * known prefixes and is SATA-1.  As a side effect LPM partial is
4237 	 * lost too.
4238 	 *
4239 	 * https://bugzilla.kernel.org/show_bug.cgi?id=57211
4240 	 */
4241 	{ "WDC WD800JD-*",		NULL,	ATA_HORKAGE_WD_BROKEN_LPM },
4242 	{ "WDC WD1200JD-*",		NULL,	ATA_HORKAGE_WD_BROKEN_LPM },
4243 	{ "WDC WD1600JD-*",		NULL,	ATA_HORKAGE_WD_BROKEN_LPM },
4244 	{ "WDC WD2000JD-*",		NULL,	ATA_HORKAGE_WD_BROKEN_LPM },
4245 	{ "WDC WD2500JD-*",		NULL,	ATA_HORKAGE_WD_BROKEN_LPM },
4246 	{ "WDC WD3000JD-*",		NULL,	ATA_HORKAGE_WD_BROKEN_LPM },
4247 	{ "WDC WD3200JD-*",		NULL,	ATA_HORKAGE_WD_BROKEN_LPM },
4248 
4249 	/* End Marker */
4250 	{ }
4251 };
4252 
4253 /**
4254  *	glob_match - match a text string against a glob-style pattern
4255  *	@text: the string to be examined
4256  *	@pattern: the glob-style pattern to be matched against
4257  *
4258  *	Either/both of text and pattern can be empty strings.
4259  *
4260  *	Match text against a glob-style pattern, with wildcards and simple sets:
4261  *
4262  *		?	matches any single character.
4263  *		*	matches any run of characters.
4264  *		[xyz]	matches a single character from the set: x, y, or z.
4265  *		[a-d]	matches a single character from the range: a, b, c, or d.
4266  *		[a-d0-9] matches a single character from either range.
4267  *
4268  *	The special characters ?, [, -, or *, can be matched using a set, eg. [*]
4269  *	Behaviour with malformed patterns is undefined, though generally reasonable.
4270  *
4271  *	Sample patterns:  "SD1?",  "SD1[0-5]",  "*R0",  "SD*1?[012]*xx"
4272  *
4273  *	This function uses one level of recursion per '*' in pattern.
4274  *	Since it calls _nothing_ else, and has _no_ explicit local variables,
4275  *	this will not cause stack problems for any reasonable use here.
4276  *
4277  *	RETURNS:
4278  *	0 on match, 1 otherwise.
4279  */
4280 static int glob_match (const char *text, const char *pattern)
4281 {
4282 	do {
4283 		/* Match single character or a '?' wildcard */
4284 		if (*text == *pattern || *pattern == '?') {
4285 			if (!*pattern++)
4286 				return 0;  /* End of both strings: match */
4287 		} else {
4288 			/* Match single char against a '[' bracketed ']' pattern set */
4289 			if (!*text || *pattern != '[')
4290 				break;  /* Not a pattern set */
4291 			while (*++pattern && *pattern != ']' && *text != *pattern) {
4292 				if (*pattern == '-' && *(pattern - 1) != '[')
4293 					if (*text > *(pattern - 1) && *text < *(pattern + 1)) {
4294 						++pattern;
4295 						break;
4296 					}
4297 			}
4298 			if (!*pattern || *pattern == ']')
4299 				return 1;  /* No match */
4300 			while (*pattern && *pattern++ != ']');
4301 		}
4302 	} while (*++text && *pattern);
4303 
4304 	/* Match any run of chars against a '*' wildcard */
4305 	if (*pattern == '*') {
4306 		if (!*++pattern)
4307 			return 0;  /* Match: avoid recursion at end of pattern */
4308 		/* Loop to handle additional pattern chars after the wildcard */
4309 		while (*text) {
4310 			if (glob_match(text, pattern) == 0)
4311 				return 0;  /* Remainder matched */
4312 			++text;  /* Absorb (match) this char and try again */
4313 		}
4314 	}
4315 	if (!*text && !*pattern)
4316 		return 0;  /* End of both strings: match */
4317 	return 1;  /* No match */
4318 }
4319 
4320 static unsigned long ata_dev_blacklisted(const struct ata_device *dev)
4321 {
4322 	unsigned char model_num[ATA_ID_PROD_LEN + 1];
4323 	unsigned char model_rev[ATA_ID_FW_REV_LEN + 1];
4324 	const struct ata_blacklist_entry *ad = ata_device_blacklist;
4325 
4326 	ata_id_c_string(dev->id, model_num, ATA_ID_PROD, sizeof(model_num));
4327 	ata_id_c_string(dev->id, model_rev, ATA_ID_FW_REV, sizeof(model_rev));
4328 
4329 	while (ad->model_num) {
4330 		if (!glob_match(model_num, ad->model_num)) {
4331 			if (ad->model_rev == NULL)
4332 				return ad->horkage;
4333 			if (!glob_match(model_rev, ad->model_rev))
4334 				return ad->horkage;
4335 		}
4336 		ad++;
4337 	}
4338 	return 0;
4339 }
4340 
4341 static int ata_dma_blacklisted(const struct ata_device *dev)
4342 {
4343 	/* We don't support polling DMA.
4344 	 * DMA blacklist those ATAPI devices with CDB-intr (and use PIO)
4345 	 * if the LLDD handles only interrupts in the HSM_ST_LAST state.
4346 	 */
4347 	if ((dev->link->ap->flags & ATA_FLAG_PIO_POLLING) &&
4348 	    (dev->flags & ATA_DFLAG_CDB_INTR))
4349 		return 1;
4350 	return (dev->horkage & ATA_HORKAGE_NODMA) ? 1 : 0;
4351 }
4352 
4353 /**
4354  *	ata_is_40wire		-	check drive side detection
4355  *	@dev: device
4356  *
4357  *	Perform drive side detection decoding, allowing for device vendors
4358  *	who can't follow the documentation.
4359  */
4360 
4361 static int ata_is_40wire(struct ata_device *dev)
4362 {
4363 	if (dev->horkage & ATA_HORKAGE_IVB)
4364 		return ata_drive_40wire_relaxed(dev->id);
4365 	return ata_drive_40wire(dev->id);
4366 }
4367 
4368 /**
4369  *	cable_is_40wire		-	40/80/SATA decider
4370  *	@ap: port to consider
4371  *
4372  *	This function encapsulates the policy for speed management
4373  *	in one place. At the moment we don't cache the result but
4374  *	there is a good case for setting ap->cbl to the result when
4375  *	we are called with unknown cables (and figuring out if it
4376  *	impacts hotplug at all).
4377  *
4378  *	Return 1 if the cable appears to be 40 wire.
4379  */
4380 
4381 static int cable_is_40wire(struct ata_port *ap)
4382 {
4383 	struct ata_link *link;
4384 	struct ata_device *dev;
4385 
4386 	/* If the controller thinks we are 40 wire, we are. */
4387 	if (ap->cbl == ATA_CBL_PATA40)
4388 		return 1;
4389 
4390 	/* If the controller thinks we are 80 wire, we are. */
4391 	if (ap->cbl == ATA_CBL_PATA80 || ap->cbl == ATA_CBL_SATA)
4392 		return 0;
4393 
4394 	/* If the system is known to be 40 wire short cable (eg
4395 	 * laptop), then we allow 80 wire modes even if the drive
4396 	 * isn't sure.
4397 	 */
4398 	if (ap->cbl == ATA_CBL_PATA40_SHORT)
4399 		return 0;
4400 
4401 	/* If the controller doesn't know, we scan.
4402 	 *
4403 	 * Note: We look for all 40 wire detects at this point.  Any
4404 	 *       80 wire detect is taken to be 80 wire cable because
4405 	 * - in many setups only the one drive (slave if present) will
4406 	 *   give a valid detect
4407 	 * - if you have a non detect capable drive you don't want it
4408 	 *   to colour the choice
4409 	 */
4410 	ata_for_each_link(link, ap, EDGE) {
4411 		ata_for_each_dev(dev, link, ENABLED) {
4412 			if (!ata_is_40wire(dev))
4413 				return 0;
4414 		}
4415 	}
4416 	return 1;
4417 }
4418 
4419 /**
4420  *	ata_dev_xfermask - Compute supported xfermask of the given device
4421  *	@dev: Device to compute xfermask for
4422  *
4423  *	Compute supported xfermask of @dev and store it in
4424  *	dev->*_mask.  This function is responsible for applying all
4425  *	known limits including host controller limits, device
4426  *	blacklist, etc...
4427  *
4428  *	LOCKING:
4429  *	None.
4430  */
4431 static void ata_dev_xfermask(struct ata_device *dev)
4432 {
4433 	struct ata_link *link = dev->link;
4434 	struct ata_port *ap = link->ap;
4435 	struct ata_host *host = ap->host;
4436 	unsigned long xfer_mask;
4437 
4438 	/* controller modes available */
4439 	xfer_mask = ata_pack_xfermask(ap->pio_mask,
4440 				      ap->mwdma_mask, ap->udma_mask);
4441 
4442 	/* drive modes available */
4443 	xfer_mask &= ata_pack_xfermask(dev->pio_mask,
4444 				       dev->mwdma_mask, dev->udma_mask);
4445 	xfer_mask &= ata_id_xfermask(dev->id);
4446 
4447 	/*
4448 	 *	CFA Advanced TrueIDE timings are not allowed on a shared
4449 	 *	cable
4450 	 */
4451 	if (ata_dev_pair(dev)) {
4452 		/* No PIO5 or PIO6 */
4453 		xfer_mask &= ~(0x03 << (ATA_SHIFT_PIO + 5));
4454 		/* No MWDMA3 or MWDMA 4 */
4455 		xfer_mask &= ~(0x03 << (ATA_SHIFT_MWDMA + 3));
4456 	}
4457 
4458 	if (ata_dma_blacklisted(dev)) {
4459 		xfer_mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA);
4460 		ata_dev_warn(dev,
4461 			     "device is on DMA blacklist, disabling DMA\n");
4462 	}
4463 
4464 	if ((host->flags & ATA_HOST_SIMPLEX) &&
4465 	    host->simplex_claimed && host->simplex_claimed != ap) {
4466 		xfer_mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA);
4467 		ata_dev_warn(dev,
4468 			     "simplex DMA is claimed by other device, disabling DMA\n");
4469 	}
4470 
4471 	if (ap->flags & ATA_FLAG_NO_IORDY)
4472 		xfer_mask &= ata_pio_mask_no_iordy(dev);
4473 
4474 	if (ap->ops->mode_filter)
4475 		xfer_mask = ap->ops->mode_filter(dev, xfer_mask);
4476 
4477 	/* Apply cable rule here.  Don't apply it early because when
4478 	 * we handle hot plug the cable type can itself change.
4479 	 * Check this last so that we know if the transfer rate was
4480 	 * solely limited by the cable.
4481 	 * Unknown or 80 wire cables reported host side are checked
4482 	 * drive side as well. Cases where we know a 40wire cable
4483 	 * is used safely for 80 are not checked here.
4484 	 */
4485 	if (xfer_mask & (0xF8 << ATA_SHIFT_UDMA))
4486 		/* UDMA/44 or higher would be available */
4487 		if (cable_is_40wire(ap)) {
4488 			ata_dev_warn(dev,
4489 				     "limited to UDMA/33 due to 40-wire cable\n");
4490 			xfer_mask &= ~(0xF8 << ATA_SHIFT_UDMA);
4491 		}
4492 
4493 	ata_unpack_xfermask(xfer_mask, &dev->pio_mask,
4494 			    &dev->mwdma_mask, &dev->udma_mask);
4495 }
4496 
4497 /**
4498  *	ata_dev_set_xfermode - Issue SET FEATURES - XFER MODE command
4499  *	@dev: Device to which command will be sent
4500  *
4501  *	Issue SET FEATURES - XFER MODE command to device @dev
4502  *	on port @ap.
4503  *
4504  *	LOCKING:
4505  *	PCI/etc. bus probe sem.
4506  *
4507  *	RETURNS:
4508  *	0 on success, AC_ERR_* mask otherwise.
4509  */
4510 
4511 static unsigned int ata_dev_set_xfermode(struct ata_device *dev)
4512 {
4513 	struct ata_taskfile tf;
4514 	unsigned int err_mask;
4515 
4516 	/* set up set-features taskfile */
4517 	DPRINTK("set features - xfer mode\n");
4518 
4519 	/* Some controllers and ATAPI devices show flaky interrupt
4520 	 * behavior after setting xfer mode.  Use polling instead.
4521 	 */
4522 	ata_tf_init(dev, &tf);
4523 	tf.command = ATA_CMD_SET_FEATURES;
4524 	tf.feature = SETFEATURES_XFER;
4525 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE | ATA_TFLAG_POLLING;
4526 	tf.protocol = ATA_PROT_NODATA;
4527 	/* If we are using IORDY we must send the mode setting command */
4528 	if (ata_pio_need_iordy(dev))
4529 		tf.nsect = dev->xfer_mode;
4530 	/* If the device has IORDY and the controller does not - turn it off */
4531  	else if (ata_id_has_iordy(dev->id))
4532 		tf.nsect = 0x01;
4533 	else /* In the ancient relic department - skip all of this */
4534 		return 0;
4535 
4536 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
4537 
4538 	DPRINTK("EXIT, err_mask=%x\n", err_mask);
4539 	return err_mask;
4540 }
4541 
4542 /**
4543  *	ata_dev_set_feature - Issue SET FEATURES - SATA FEATURES
4544  *	@dev: Device to which command will be sent
4545  *	@enable: Whether to enable or disable the feature
4546  *	@feature: The sector count represents the feature to set
4547  *
4548  *	Issue SET FEATURES - SATA FEATURES command to device @dev
4549  *	on port @ap with sector count
4550  *
4551  *	LOCKING:
4552  *	PCI/etc. bus probe sem.
4553  *
4554  *	RETURNS:
4555  *	0 on success, AC_ERR_* mask otherwise.
4556  */
4557 unsigned int ata_dev_set_feature(struct ata_device *dev, u8 enable, u8 feature)
4558 {
4559 	struct ata_taskfile tf;
4560 	unsigned int err_mask;
4561 
4562 	/* set up set-features taskfile */
4563 	DPRINTK("set features - SATA features\n");
4564 
4565 	ata_tf_init(dev, &tf);
4566 	tf.command = ATA_CMD_SET_FEATURES;
4567 	tf.feature = enable;
4568 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
4569 	tf.protocol = ATA_PROT_NODATA;
4570 	tf.nsect = feature;
4571 
4572 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
4573 
4574 	DPRINTK("EXIT, err_mask=%x\n", err_mask);
4575 	return err_mask;
4576 }
4577 EXPORT_SYMBOL_GPL(ata_dev_set_feature);
4578 
4579 /**
4580  *	ata_dev_init_params - Issue INIT DEV PARAMS command
4581  *	@dev: Device to which command will be sent
4582  *	@heads: Number of heads (taskfile parameter)
4583  *	@sectors: Number of sectors (taskfile parameter)
4584  *
4585  *	LOCKING:
4586  *	Kernel thread context (may sleep)
4587  *
4588  *	RETURNS:
4589  *	0 on success, AC_ERR_* mask otherwise.
4590  */
4591 static unsigned int ata_dev_init_params(struct ata_device *dev,
4592 					u16 heads, u16 sectors)
4593 {
4594 	struct ata_taskfile tf;
4595 	unsigned int err_mask;
4596 
4597 	/* Number of sectors per track 1-255. Number of heads 1-16 */
4598 	if (sectors < 1 || sectors > 255 || heads < 1 || heads > 16)
4599 		return AC_ERR_INVALID;
4600 
4601 	/* set up init dev params taskfile */
4602 	DPRINTK("init dev params \n");
4603 
4604 	ata_tf_init(dev, &tf);
4605 	tf.command = ATA_CMD_INIT_DEV_PARAMS;
4606 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
4607 	tf.protocol = ATA_PROT_NODATA;
4608 	tf.nsect = sectors;
4609 	tf.device |= (heads - 1) & 0x0f; /* max head = num. of heads - 1 */
4610 
4611 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
4612 	/* A clean abort indicates an original or just out of spec drive
4613 	   and we should continue as we issue the setup based on the
4614 	   drive reported working geometry */
4615 	if (err_mask == AC_ERR_DEV && (tf.feature & ATA_ABORTED))
4616 		err_mask = 0;
4617 
4618 	DPRINTK("EXIT, err_mask=%x\n", err_mask);
4619 	return err_mask;
4620 }
4621 
4622 /**
4623  *	ata_sg_clean - Unmap DMA memory associated with command
4624  *	@qc: Command containing DMA memory to be released
4625  *
4626  *	Unmap all mapped DMA memory associated with this command.
4627  *
4628  *	LOCKING:
4629  *	spin_lock_irqsave(host lock)
4630  */
4631 void ata_sg_clean(struct ata_queued_cmd *qc)
4632 {
4633 	struct ata_port *ap = qc->ap;
4634 	struct scatterlist *sg = qc->sg;
4635 	int dir = qc->dma_dir;
4636 
4637 	WARN_ON_ONCE(sg == NULL);
4638 
4639 	VPRINTK("unmapping %u sg elements\n", qc->n_elem);
4640 
4641 	if (qc->n_elem)
4642 		dma_unmap_sg(ap->dev, sg, qc->orig_n_elem, dir);
4643 
4644 	qc->flags &= ~ATA_QCFLAG_DMAMAP;
4645 	qc->sg = NULL;
4646 }
4647 
4648 /**
4649  *	atapi_check_dma - Check whether ATAPI DMA can be supported
4650  *	@qc: Metadata associated with taskfile to check
4651  *
4652  *	Allow low-level driver to filter ATA PACKET commands, returning
4653  *	a status indicating whether or not it is OK to use DMA for the
4654  *	supplied PACKET command.
4655  *
4656  *	LOCKING:
4657  *	spin_lock_irqsave(host lock)
4658  *
4659  *	RETURNS: 0 when ATAPI DMA can be used
4660  *               nonzero otherwise
4661  */
4662 int atapi_check_dma(struct ata_queued_cmd *qc)
4663 {
4664 	struct ata_port *ap = qc->ap;
4665 
4666 	/* Don't allow DMA if it isn't multiple of 16 bytes.  Quite a
4667 	 * few ATAPI devices choke on such DMA requests.
4668 	 */
4669 	if (!(qc->dev->horkage & ATA_HORKAGE_ATAPI_MOD16_DMA) &&
4670 	    unlikely(qc->nbytes & 15))
4671 		return 1;
4672 
4673 	if (ap->ops->check_atapi_dma)
4674 		return ap->ops->check_atapi_dma(qc);
4675 
4676 	return 0;
4677 }
4678 
4679 /**
4680  *	ata_std_qc_defer - Check whether a qc needs to be deferred
4681  *	@qc: ATA command in question
4682  *
4683  *	Non-NCQ commands cannot run with any other command, NCQ or
4684  *	not.  As upper layer only knows the queue depth, we are
4685  *	responsible for maintaining exclusion.  This function checks
4686  *	whether a new command @qc can be issued.
4687  *
4688  *	LOCKING:
4689  *	spin_lock_irqsave(host lock)
4690  *
4691  *	RETURNS:
4692  *	ATA_DEFER_* if deferring is needed, 0 otherwise.
4693  */
4694 int ata_std_qc_defer(struct ata_queued_cmd *qc)
4695 {
4696 	struct ata_link *link = qc->dev->link;
4697 
4698 	if (qc->tf.protocol == ATA_PROT_NCQ) {
4699 		if (!ata_tag_valid(link->active_tag))
4700 			return 0;
4701 	} else {
4702 		if (!ata_tag_valid(link->active_tag) && !link->sactive)
4703 			return 0;
4704 	}
4705 
4706 	return ATA_DEFER_LINK;
4707 }
4708 
4709 void ata_noop_qc_prep(struct ata_queued_cmd *qc) { }
4710 
4711 /**
4712  *	ata_sg_init - Associate command with scatter-gather table.
4713  *	@qc: Command to be associated
4714  *	@sg: Scatter-gather table.
4715  *	@n_elem: Number of elements in s/g table.
4716  *
4717  *	Initialize the data-related elements of queued_cmd @qc
4718  *	to point to a scatter-gather table @sg, containing @n_elem
4719  *	elements.
4720  *
4721  *	LOCKING:
4722  *	spin_lock_irqsave(host lock)
4723  */
4724 void ata_sg_init(struct ata_queued_cmd *qc, struct scatterlist *sg,
4725 		 unsigned int n_elem)
4726 {
4727 	qc->sg = sg;
4728 	qc->n_elem = n_elem;
4729 	qc->cursg = qc->sg;
4730 }
4731 
4732 /**
4733  *	ata_sg_setup - DMA-map the scatter-gather table associated with a command.
4734  *	@qc: Command with scatter-gather table to be mapped.
4735  *
4736  *	DMA-map the scatter-gather table associated with queued_cmd @qc.
4737  *
4738  *	LOCKING:
4739  *	spin_lock_irqsave(host lock)
4740  *
4741  *	RETURNS:
4742  *	Zero on success, negative on error.
4743  *
4744  */
4745 static int ata_sg_setup(struct ata_queued_cmd *qc)
4746 {
4747 	struct ata_port *ap = qc->ap;
4748 	unsigned int n_elem;
4749 
4750 	VPRINTK("ENTER, ata%u\n", ap->print_id);
4751 
4752 	n_elem = dma_map_sg(ap->dev, qc->sg, qc->n_elem, qc->dma_dir);
4753 	if (n_elem < 1)
4754 		return -1;
4755 
4756 	DPRINTK("%d sg elements mapped\n", n_elem);
4757 	qc->orig_n_elem = qc->n_elem;
4758 	qc->n_elem = n_elem;
4759 	qc->flags |= ATA_QCFLAG_DMAMAP;
4760 
4761 	return 0;
4762 }
4763 
4764 /**
4765  *	swap_buf_le16 - swap halves of 16-bit words in place
4766  *	@buf:  Buffer to swap
4767  *	@buf_words:  Number of 16-bit words in buffer.
4768  *
4769  *	Swap halves of 16-bit words if needed to convert from
4770  *	little-endian byte order to native cpu byte order, or
4771  *	vice-versa.
4772  *
4773  *	LOCKING:
4774  *	Inherited from caller.
4775  */
4776 void swap_buf_le16(u16 *buf, unsigned int buf_words)
4777 {
4778 #ifdef __BIG_ENDIAN
4779 	unsigned int i;
4780 
4781 	for (i = 0; i < buf_words; i++)
4782 		buf[i] = le16_to_cpu(buf[i]);
4783 #endif /* __BIG_ENDIAN */
4784 }
4785 
4786 /**
4787  *	ata_qc_new - Request an available ATA command, for queueing
4788  *	@ap: target port
4789  *
4790  *	LOCKING:
4791  *	None.
4792  */
4793 
4794 static struct ata_queued_cmd *ata_qc_new(struct ata_port *ap)
4795 {
4796 	struct ata_queued_cmd *qc = NULL;
4797 	unsigned int i, tag;
4798 
4799 	/* no command while frozen */
4800 	if (unlikely(ap->pflags & ATA_PFLAG_FROZEN))
4801 		return NULL;
4802 
4803 	for (i = 0; i < ATA_MAX_QUEUE; i++) {
4804 		tag = (i + ap->last_tag + 1) % ATA_MAX_QUEUE;
4805 
4806 		/* the last tag is reserved for internal command. */
4807 		if (tag == ATA_TAG_INTERNAL)
4808 			continue;
4809 
4810 		if (!test_and_set_bit(tag, &ap->qc_allocated)) {
4811 			qc = __ata_qc_from_tag(ap, tag);
4812 			qc->tag = tag;
4813 			ap->last_tag = tag;
4814 			break;
4815 		}
4816 	}
4817 
4818 	return qc;
4819 }
4820 
4821 /**
4822  *	ata_qc_new_init - Request an available ATA command, and initialize it
4823  *	@dev: Device from whom we request an available command structure
4824  *
4825  *	LOCKING:
4826  *	None.
4827  */
4828 
4829 struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev)
4830 {
4831 	struct ata_port *ap = dev->link->ap;
4832 	struct ata_queued_cmd *qc;
4833 
4834 	qc = ata_qc_new(ap);
4835 	if (qc) {
4836 		qc->scsicmd = NULL;
4837 		qc->ap = ap;
4838 		qc->dev = dev;
4839 
4840 		ata_qc_reinit(qc);
4841 	}
4842 
4843 	return qc;
4844 }
4845 
4846 /**
4847  *	ata_qc_free - free unused ata_queued_cmd
4848  *	@qc: Command to complete
4849  *
4850  *	Designed to free unused ata_queued_cmd object
4851  *	in case something prevents using it.
4852  *
4853  *	LOCKING:
4854  *	spin_lock_irqsave(host lock)
4855  */
4856 void ata_qc_free(struct ata_queued_cmd *qc)
4857 {
4858 	struct ata_port *ap;
4859 	unsigned int tag;
4860 
4861 	WARN_ON_ONCE(qc == NULL); /* ata_qc_from_tag _might_ return NULL */
4862 	ap = qc->ap;
4863 
4864 	qc->flags = 0;
4865 	tag = qc->tag;
4866 	if (likely(ata_tag_valid(tag))) {
4867 		qc->tag = ATA_TAG_POISON;
4868 		clear_bit(tag, &ap->qc_allocated);
4869 	}
4870 }
4871 
4872 void __ata_qc_complete(struct ata_queued_cmd *qc)
4873 {
4874 	struct ata_port *ap;
4875 	struct ata_link *link;
4876 
4877 	WARN_ON_ONCE(qc == NULL); /* ata_qc_from_tag _might_ return NULL */
4878 	WARN_ON_ONCE(!(qc->flags & ATA_QCFLAG_ACTIVE));
4879 	ap = qc->ap;
4880 	link = qc->dev->link;
4881 
4882 	if (likely(qc->flags & ATA_QCFLAG_DMAMAP))
4883 		ata_sg_clean(qc);
4884 
4885 	/* command should be marked inactive atomically with qc completion */
4886 	if (qc->tf.protocol == ATA_PROT_NCQ) {
4887 		link->sactive &= ~(1 << qc->tag);
4888 		if (!link->sactive)
4889 			ap->nr_active_links--;
4890 	} else {
4891 		link->active_tag = ATA_TAG_POISON;
4892 		ap->nr_active_links--;
4893 	}
4894 
4895 	/* clear exclusive status */
4896 	if (unlikely(qc->flags & ATA_QCFLAG_CLEAR_EXCL &&
4897 		     ap->excl_link == link))
4898 		ap->excl_link = NULL;
4899 
4900 	/* atapi: mark qc as inactive to prevent the interrupt handler
4901 	 * from completing the command twice later, before the error handler
4902 	 * is called. (when rc != 0 and atapi request sense is needed)
4903 	 */
4904 	qc->flags &= ~ATA_QCFLAG_ACTIVE;
4905 	ap->qc_active &= ~(1 << qc->tag);
4906 
4907 	/* call completion callback */
4908 	qc->complete_fn(qc);
4909 }
4910 
4911 static void fill_result_tf(struct ata_queued_cmd *qc)
4912 {
4913 	struct ata_port *ap = qc->ap;
4914 
4915 	qc->result_tf.flags = qc->tf.flags;
4916 	ap->ops->qc_fill_rtf(qc);
4917 }
4918 
4919 static void ata_verify_xfer(struct ata_queued_cmd *qc)
4920 {
4921 	struct ata_device *dev = qc->dev;
4922 
4923 	if (ata_is_nodata(qc->tf.protocol))
4924 		return;
4925 
4926 	if ((dev->mwdma_mask || dev->udma_mask) && ata_is_pio(qc->tf.protocol))
4927 		return;
4928 
4929 	dev->flags &= ~ATA_DFLAG_DUBIOUS_XFER;
4930 }
4931 
4932 /**
4933  *	ata_qc_complete - Complete an active ATA command
4934  *	@qc: Command to complete
4935  *
4936  *	Indicate to the mid and upper layers that an ATA command has
4937  *	completed, with either an ok or not-ok status.
4938  *
4939  *	Refrain from calling this function multiple times when
4940  *	successfully completing multiple NCQ commands.
4941  *	ata_qc_complete_multiple() should be used instead, which will
4942  *	properly update IRQ expect state.
4943  *
4944  *	LOCKING:
4945  *	spin_lock_irqsave(host lock)
4946  */
4947 void ata_qc_complete(struct ata_queued_cmd *qc)
4948 {
4949 	struct ata_port *ap = qc->ap;
4950 
4951 	/* XXX: New EH and old EH use different mechanisms to
4952 	 * synchronize EH with regular execution path.
4953 	 *
4954 	 * In new EH, a failed qc is marked with ATA_QCFLAG_FAILED.
4955 	 * Normal execution path is responsible for not accessing a
4956 	 * failed qc.  libata core enforces the rule by returning NULL
4957 	 * from ata_qc_from_tag() for failed qcs.
4958 	 *
4959 	 * Old EH depends on ata_qc_complete() nullifying completion
4960 	 * requests if ATA_QCFLAG_EH_SCHEDULED is set.  Old EH does
4961 	 * not synchronize with interrupt handler.  Only PIO task is
4962 	 * taken care of.
4963 	 */
4964 	if (ap->ops->error_handler) {
4965 		struct ata_device *dev = qc->dev;
4966 		struct ata_eh_info *ehi = &dev->link->eh_info;
4967 
4968 		if (unlikely(qc->err_mask))
4969 			qc->flags |= ATA_QCFLAG_FAILED;
4970 
4971 		/*
4972 		 * Finish internal commands without any further processing
4973 		 * and always with the result TF filled.
4974 		 */
4975 		if (unlikely(ata_tag_internal(qc->tag))) {
4976 			fill_result_tf(qc);
4977 			__ata_qc_complete(qc);
4978 			return;
4979 		}
4980 
4981 		/*
4982 		 * Non-internal qc has failed.  Fill the result TF and
4983 		 * summon EH.
4984 		 */
4985 		if (unlikely(qc->flags & ATA_QCFLAG_FAILED)) {
4986 			fill_result_tf(qc);
4987 			ata_qc_schedule_eh(qc);
4988 			return;
4989 		}
4990 
4991 		WARN_ON_ONCE(ap->pflags & ATA_PFLAG_FROZEN);
4992 
4993 		/* read result TF if requested */
4994 		if (qc->flags & ATA_QCFLAG_RESULT_TF)
4995 			fill_result_tf(qc);
4996 
4997 		/* Some commands need post-processing after successful
4998 		 * completion.
4999 		 */
5000 		switch (qc->tf.command) {
5001 		case ATA_CMD_SET_FEATURES:
5002 			if (qc->tf.feature != SETFEATURES_WC_ON &&
5003 			    qc->tf.feature != SETFEATURES_WC_OFF)
5004 				break;
5005 			/* fall through */
5006 		case ATA_CMD_INIT_DEV_PARAMS: /* CHS translation changed */
5007 		case ATA_CMD_SET_MULTI: /* multi_count changed */
5008 			/* revalidate device */
5009 			ehi->dev_action[dev->devno] |= ATA_EH_REVALIDATE;
5010 			ata_port_schedule_eh(ap);
5011 			break;
5012 
5013 		case ATA_CMD_SLEEP:
5014 			dev->flags |= ATA_DFLAG_SLEEPING;
5015 			break;
5016 		}
5017 
5018 		if (unlikely(dev->flags & ATA_DFLAG_DUBIOUS_XFER))
5019 			ata_verify_xfer(qc);
5020 
5021 		__ata_qc_complete(qc);
5022 	} else {
5023 		if (qc->flags & ATA_QCFLAG_EH_SCHEDULED)
5024 			return;
5025 
5026 		/* read result TF if failed or requested */
5027 		if (qc->err_mask || qc->flags & ATA_QCFLAG_RESULT_TF)
5028 			fill_result_tf(qc);
5029 
5030 		__ata_qc_complete(qc);
5031 	}
5032 }
5033 
5034 /**
5035  *	ata_qc_complete_multiple - Complete multiple qcs successfully
5036  *	@ap: port in question
5037  *	@qc_active: new qc_active mask
5038  *
5039  *	Complete in-flight commands.  This functions is meant to be
5040  *	called from low-level driver's interrupt routine to complete
5041  *	requests normally.  ap->qc_active and @qc_active is compared
5042  *	and commands are completed accordingly.
5043  *
5044  *	Always use this function when completing multiple NCQ commands
5045  *	from IRQ handlers instead of calling ata_qc_complete()
5046  *	multiple times to keep IRQ expect status properly in sync.
5047  *
5048  *	LOCKING:
5049  *	spin_lock_irqsave(host lock)
5050  *
5051  *	RETURNS:
5052  *	Number of completed commands on success, -errno otherwise.
5053  */
5054 int ata_qc_complete_multiple(struct ata_port *ap, u32 qc_active)
5055 {
5056 	int nr_done = 0;
5057 	u32 done_mask;
5058 
5059 	done_mask = ap->qc_active ^ qc_active;
5060 
5061 	if (unlikely(done_mask & qc_active)) {
5062 		ata_port_err(ap, "illegal qc_active transition (%08x->%08x)\n",
5063 			     ap->qc_active, qc_active);
5064 		return -EINVAL;
5065 	}
5066 
5067 	while (done_mask) {
5068 		struct ata_queued_cmd *qc;
5069 		unsigned int tag = __ffs(done_mask);
5070 
5071 		qc = ata_qc_from_tag(ap, tag);
5072 		if (qc) {
5073 			ata_qc_complete(qc);
5074 			nr_done++;
5075 		}
5076 		done_mask &= ~(1 << tag);
5077 	}
5078 
5079 	return nr_done;
5080 }
5081 
5082 /**
5083  *	ata_qc_issue - issue taskfile to device
5084  *	@qc: command to issue to device
5085  *
5086  *	Prepare an ATA command to submission to device.
5087  *	This includes mapping the data into a DMA-able
5088  *	area, filling in the S/G table, and finally
5089  *	writing the taskfile to hardware, starting the command.
5090  *
5091  *	LOCKING:
5092  *	spin_lock_irqsave(host lock)
5093  */
5094 void ata_qc_issue(struct ata_queued_cmd *qc)
5095 {
5096 	struct ata_port *ap = qc->ap;
5097 	struct ata_link *link = qc->dev->link;
5098 	u8 prot = qc->tf.protocol;
5099 
5100 	/* Make sure only one non-NCQ command is outstanding.  The
5101 	 * check is skipped for old EH because it reuses active qc to
5102 	 * request ATAPI sense.
5103 	 */
5104 	WARN_ON_ONCE(ap->ops->error_handler && ata_tag_valid(link->active_tag));
5105 
5106 	if (ata_is_ncq(prot)) {
5107 		WARN_ON_ONCE(link->sactive & (1 << qc->tag));
5108 
5109 		if (!link->sactive)
5110 			ap->nr_active_links++;
5111 		link->sactive |= 1 << qc->tag;
5112 	} else {
5113 		WARN_ON_ONCE(link->sactive);
5114 
5115 		ap->nr_active_links++;
5116 		link->active_tag = qc->tag;
5117 	}
5118 
5119 	qc->flags |= ATA_QCFLAG_ACTIVE;
5120 	ap->qc_active |= 1 << qc->tag;
5121 
5122 	/*
5123 	 * We guarantee to LLDs that they will have at least one
5124 	 * non-zero sg if the command is a data command.
5125 	 */
5126 	if (WARN_ON_ONCE(ata_is_data(prot) &&
5127 			 (!qc->sg || !qc->n_elem || !qc->nbytes)))
5128 		goto sys_err;
5129 
5130 	if (ata_is_dma(prot) || (ata_is_pio(prot) &&
5131 				 (ap->flags & ATA_FLAG_PIO_DMA)))
5132 		if (ata_sg_setup(qc))
5133 			goto sys_err;
5134 
5135 	/* if device is sleeping, schedule reset and abort the link */
5136 	if (unlikely(qc->dev->flags & ATA_DFLAG_SLEEPING)) {
5137 		link->eh_info.action |= ATA_EH_RESET;
5138 		ata_ehi_push_desc(&link->eh_info, "waking up from sleep");
5139 		ata_link_abort(link);
5140 		return;
5141 	}
5142 
5143 	ap->ops->qc_prep(qc);
5144 
5145 	qc->err_mask |= ap->ops->qc_issue(qc);
5146 	if (unlikely(qc->err_mask))
5147 		goto err;
5148 	return;
5149 
5150 sys_err:
5151 	qc->err_mask |= AC_ERR_SYSTEM;
5152 err:
5153 	ata_qc_complete(qc);
5154 }
5155 
5156 /**
5157  *	sata_scr_valid - test whether SCRs are accessible
5158  *	@link: ATA link to test SCR accessibility for
5159  *
5160  *	Test whether SCRs are accessible for @link.
5161  *
5162  *	LOCKING:
5163  *	None.
5164  *
5165  *	RETURNS:
5166  *	1 if SCRs are accessible, 0 otherwise.
5167  */
5168 int sata_scr_valid(struct ata_link *link)
5169 {
5170 	struct ata_port *ap = link->ap;
5171 
5172 	return (ap->flags & ATA_FLAG_SATA) && ap->ops->scr_read;
5173 }
5174 
5175 /**
5176  *	sata_scr_read - read SCR register of the specified port
5177  *	@link: ATA link to read SCR for
5178  *	@reg: SCR to read
5179  *	@val: Place to store read value
5180  *
5181  *	Read SCR register @reg of @link into *@val.  This function is
5182  *	guaranteed to succeed if @link is ap->link, the cable type of
5183  *	the port is SATA and the port implements ->scr_read.
5184  *
5185  *	LOCKING:
5186  *	None if @link is ap->link.  Kernel thread context otherwise.
5187  *
5188  *	RETURNS:
5189  *	0 on success, negative errno on failure.
5190  */
5191 int sata_scr_read(struct ata_link *link, int reg, u32 *val)
5192 {
5193 	if (ata_is_host_link(link)) {
5194 		if (sata_scr_valid(link))
5195 			return link->ap->ops->scr_read(link, reg, val);
5196 		return -EOPNOTSUPP;
5197 	}
5198 
5199 	return sata_pmp_scr_read(link, reg, val);
5200 }
5201 
5202 /**
5203  *	sata_scr_write - write SCR register of the specified port
5204  *	@link: ATA link to write SCR for
5205  *	@reg: SCR to write
5206  *	@val: value to write
5207  *
5208  *	Write @val to SCR register @reg of @link.  This function is
5209  *	guaranteed to succeed if @link is ap->link, the cable type of
5210  *	the port is SATA and the port implements ->scr_read.
5211  *
5212  *	LOCKING:
5213  *	None if @link is ap->link.  Kernel thread context otherwise.
5214  *
5215  *	RETURNS:
5216  *	0 on success, negative errno on failure.
5217  */
5218 int sata_scr_write(struct ata_link *link, int reg, u32 val)
5219 {
5220 	if (ata_is_host_link(link)) {
5221 		if (sata_scr_valid(link))
5222 			return link->ap->ops->scr_write(link, reg, val);
5223 		return -EOPNOTSUPP;
5224 	}
5225 
5226 	return sata_pmp_scr_write(link, reg, val);
5227 }
5228 
5229 /**
5230  *	sata_scr_write_flush - write SCR register of the specified port and flush
5231  *	@link: ATA link to write SCR for
5232  *	@reg: SCR to write
5233  *	@val: value to write
5234  *
5235  *	This function is identical to sata_scr_write() except that this
5236  *	function performs flush after writing to the register.
5237  *
5238  *	LOCKING:
5239  *	None if @link is ap->link.  Kernel thread context otherwise.
5240  *
5241  *	RETURNS:
5242  *	0 on success, negative errno on failure.
5243  */
5244 int sata_scr_write_flush(struct ata_link *link, int reg, u32 val)
5245 {
5246 	if (ata_is_host_link(link)) {
5247 		int rc;
5248 
5249 		if (sata_scr_valid(link)) {
5250 			rc = link->ap->ops->scr_write(link, reg, val);
5251 			if (rc == 0)
5252 				rc = link->ap->ops->scr_read(link, reg, &val);
5253 			return rc;
5254 		}
5255 		return -EOPNOTSUPP;
5256 	}
5257 
5258 	return sata_pmp_scr_write(link, reg, val);
5259 }
5260 
5261 /**
5262  *	ata_phys_link_online - test whether the given link is online
5263  *	@link: ATA link to test
5264  *
5265  *	Test whether @link is online.  Note that this function returns
5266  *	0 if online status of @link cannot be obtained, so
5267  *	ata_link_online(link) != !ata_link_offline(link).
5268  *
5269  *	LOCKING:
5270  *	None.
5271  *
5272  *	RETURNS:
5273  *	True if the port online status is available and online.
5274  */
5275 bool ata_phys_link_online(struct ata_link *link)
5276 {
5277 	u32 sstatus;
5278 
5279 	if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0 &&
5280 	    ata_sstatus_online(sstatus))
5281 		return true;
5282 	return false;
5283 }
5284 
5285 /**
5286  *	ata_phys_link_offline - test whether the given link is offline
5287  *	@link: ATA link to test
5288  *
5289  *	Test whether @link is offline.  Note that this function
5290  *	returns 0 if offline status of @link cannot be obtained, so
5291  *	ata_link_online(link) != !ata_link_offline(link).
5292  *
5293  *	LOCKING:
5294  *	None.
5295  *
5296  *	RETURNS:
5297  *	True if the port offline status is available and offline.
5298  */
5299 bool ata_phys_link_offline(struct ata_link *link)
5300 {
5301 	u32 sstatus;
5302 
5303 	if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0 &&
5304 	    !ata_sstatus_online(sstatus))
5305 		return true;
5306 	return false;
5307 }
5308 
5309 /**
5310  *	ata_link_online - test whether the given link is online
5311  *	@link: ATA link to test
5312  *
5313  *	Test whether @link is online.  This is identical to
5314  *	ata_phys_link_online() when there's no slave link.  When
5315  *	there's a slave link, this function should only be called on
5316  *	the master link and will return true if any of M/S links is
5317  *	online.
5318  *
5319  *	LOCKING:
5320  *	None.
5321  *
5322  *	RETURNS:
5323  *	True if the port online status is available and online.
5324  */
5325 bool ata_link_online(struct ata_link *link)
5326 {
5327 	struct ata_link *slave = link->ap->slave_link;
5328 
5329 	WARN_ON(link == slave);	/* shouldn't be called on slave link */
5330 
5331 	return ata_phys_link_online(link) ||
5332 		(slave && ata_phys_link_online(slave));
5333 }
5334 
5335 /**
5336  *	ata_link_offline - test whether the given link is offline
5337  *	@link: ATA link to test
5338  *
5339  *	Test whether @link is offline.  This is identical to
5340  *	ata_phys_link_offline() when there's no slave link.  When
5341  *	there's a slave link, this function should only be called on
5342  *	the master link and will return true if both M/S links are
5343  *	offline.
5344  *
5345  *	LOCKING:
5346  *	None.
5347  *
5348  *	RETURNS:
5349  *	True if the port offline status is available and offline.
5350  */
5351 bool ata_link_offline(struct ata_link *link)
5352 {
5353 	struct ata_link *slave = link->ap->slave_link;
5354 
5355 	WARN_ON(link == slave);	/* shouldn't be called on slave link */
5356 
5357 	return ata_phys_link_offline(link) &&
5358 		(!slave || ata_phys_link_offline(slave));
5359 }
5360 
5361 #ifdef CONFIG_PM
5362 static void ata_port_request_pm(struct ata_port *ap, pm_message_t mesg,
5363 				unsigned int action, unsigned int ehi_flags,
5364 				bool async)
5365 {
5366 	struct ata_link *link;
5367 	unsigned long flags;
5368 
5369 	/* Previous resume operation might still be in
5370 	 * progress.  Wait for PM_PENDING to clear.
5371 	 */
5372 	if (ap->pflags & ATA_PFLAG_PM_PENDING) {
5373 		ata_port_wait_eh(ap);
5374 		WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
5375 	}
5376 
5377 	/* request PM ops to EH */
5378 	spin_lock_irqsave(ap->lock, flags);
5379 
5380 	ap->pm_mesg = mesg;
5381 	ap->pflags |= ATA_PFLAG_PM_PENDING;
5382 	ata_for_each_link(link, ap, HOST_FIRST) {
5383 		link->eh_info.action |= action;
5384 		link->eh_info.flags |= ehi_flags;
5385 	}
5386 
5387 	ata_port_schedule_eh(ap);
5388 
5389 	spin_unlock_irqrestore(ap->lock, flags);
5390 
5391 	if (!async) {
5392 		ata_port_wait_eh(ap);
5393 		WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
5394 	}
5395 }
5396 
5397 /*
5398  * On some hardware, device fails to respond after spun down for suspend.  As
5399  * the device won't be used before being resumed, we don't need to touch the
5400  * device.  Ask EH to skip the usual stuff and proceed directly to suspend.
5401  *
5402  * http://thread.gmane.org/gmane.linux.ide/46764
5403  */
5404 static const unsigned int ata_port_suspend_ehi = ATA_EHI_QUIET
5405 						 | ATA_EHI_NO_AUTOPSY
5406 						 | ATA_EHI_NO_RECOVERY;
5407 
5408 static void ata_port_suspend(struct ata_port *ap, pm_message_t mesg)
5409 {
5410 	ata_port_request_pm(ap, mesg, 0, ata_port_suspend_ehi, false);
5411 }
5412 
5413 static void ata_port_suspend_async(struct ata_port *ap, pm_message_t mesg)
5414 {
5415 	ata_port_request_pm(ap, mesg, 0, ata_port_suspend_ehi, true);
5416 }
5417 
5418 static int ata_port_pm_suspend(struct device *dev)
5419 {
5420 	struct ata_port *ap = to_ata_port(dev);
5421 
5422 	if (pm_runtime_suspended(dev))
5423 		return 0;
5424 
5425 	ata_port_suspend(ap, PMSG_SUSPEND);
5426 	return 0;
5427 }
5428 
5429 static int ata_port_pm_freeze(struct device *dev)
5430 {
5431 	struct ata_port *ap = to_ata_port(dev);
5432 
5433 	if (pm_runtime_suspended(dev))
5434 		return 0;
5435 
5436 	ata_port_suspend(ap, PMSG_FREEZE);
5437 	return 0;
5438 }
5439 
5440 static int ata_port_pm_poweroff(struct device *dev)
5441 {
5442 	ata_port_suspend(to_ata_port(dev), PMSG_HIBERNATE);
5443 	return 0;
5444 }
5445 
5446 static const unsigned int ata_port_resume_ehi = ATA_EHI_NO_AUTOPSY
5447 						| ATA_EHI_QUIET;
5448 
5449 static void ata_port_resume(struct ata_port *ap, pm_message_t mesg)
5450 {
5451 	ata_port_request_pm(ap, mesg, ATA_EH_RESET, ata_port_resume_ehi, false);
5452 }
5453 
5454 static void ata_port_resume_async(struct ata_port *ap, pm_message_t mesg)
5455 {
5456 	ata_port_request_pm(ap, mesg, ATA_EH_RESET, ata_port_resume_ehi, true);
5457 }
5458 
5459 static int ata_port_pm_resume(struct device *dev)
5460 {
5461 	ata_port_resume_async(to_ata_port(dev), PMSG_RESUME);
5462 	pm_runtime_disable(dev);
5463 	pm_runtime_set_active(dev);
5464 	pm_runtime_enable(dev);
5465 	return 0;
5466 }
5467 
5468 /*
5469  * For ODDs, the upper layer will poll for media change every few seconds,
5470  * which will make it enter and leave suspend state every few seconds. And
5471  * as each suspend will cause a hard/soft reset, the gain of runtime suspend
5472  * is very little and the ODD may malfunction after constantly being reset.
5473  * So the idle callback here will not proceed to suspend if a non-ZPODD capable
5474  * ODD is attached to the port.
5475  */
5476 static int ata_port_runtime_idle(struct device *dev)
5477 {
5478 	struct ata_port *ap = to_ata_port(dev);
5479 	struct ata_link *link;
5480 	struct ata_device *adev;
5481 
5482 	ata_for_each_link(link, ap, HOST_FIRST) {
5483 		ata_for_each_dev(adev, link, ENABLED)
5484 			if (adev->class == ATA_DEV_ATAPI &&
5485 			    !zpodd_dev_enabled(adev))
5486 				return -EBUSY;
5487 	}
5488 
5489 	return 0;
5490 }
5491 
5492 static int ata_port_runtime_suspend(struct device *dev)
5493 {
5494 	ata_port_suspend(to_ata_port(dev), PMSG_AUTO_SUSPEND);
5495 	return 0;
5496 }
5497 
5498 static int ata_port_runtime_resume(struct device *dev)
5499 {
5500 	ata_port_resume(to_ata_port(dev), PMSG_AUTO_RESUME);
5501 	return 0;
5502 }
5503 
5504 static const struct dev_pm_ops ata_port_pm_ops = {
5505 	.suspend = ata_port_pm_suspend,
5506 	.resume = ata_port_pm_resume,
5507 	.freeze = ata_port_pm_freeze,
5508 	.thaw = ata_port_pm_resume,
5509 	.poweroff = ata_port_pm_poweroff,
5510 	.restore = ata_port_pm_resume,
5511 
5512 	.runtime_suspend = ata_port_runtime_suspend,
5513 	.runtime_resume = ata_port_runtime_resume,
5514 	.runtime_idle = ata_port_runtime_idle,
5515 };
5516 
5517 /* sas ports don't participate in pm runtime management of ata_ports,
5518  * and need to resume ata devices at the domain level, not the per-port
5519  * level. sas suspend/resume is async to allow parallel port recovery
5520  * since sas has multiple ata_port instances per Scsi_Host.
5521  */
5522 void ata_sas_port_suspend(struct ata_port *ap)
5523 {
5524 	ata_port_suspend_async(ap, PMSG_SUSPEND);
5525 }
5526 EXPORT_SYMBOL_GPL(ata_sas_port_suspend);
5527 
5528 void ata_sas_port_resume(struct ata_port *ap)
5529 {
5530 	ata_port_resume_async(ap, PMSG_RESUME);
5531 }
5532 EXPORT_SYMBOL_GPL(ata_sas_port_resume);
5533 
5534 /**
5535  *	ata_host_suspend - suspend host
5536  *	@host: host to suspend
5537  *	@mesg: PM message
5538  *
5539  *	Suspend @host.  Actual operation is performed by port suspend.
5540  */
5541 int ata_host_suspend(struct ata_host *host, pm_message_t mesg)
5542 {
5543 	host->dev->power.power_state = mesg;
5544 	return 0;
5545 }
5546 
5547 /**
5548  *	ata_host_resume - resume host
5549  *	@host: host to resume
5550  *
5551  *	Resume @host.  Actual operation is performed by port resume.
5552  */
5553 void ata_host_resume(struct ata_host *host)
5554 {
5555 	host->dev->power.power_state = PMSG_ON;
5556 }
5557 #endif
5558 
5559 struct device_type ata_port_type = {
5560 	.name = "ata_port",
5561 #ifdef CONFIG_PM
5562 	.pm = &ata_port_pm_ops,
5563 #endif
5564 };
5565 
5566 /**
5567  *	ata_dev_init - Initialize an ata_device structure
5568  *	@dev: Device structure to initialize
5569  *
5570  *	Initialize @dev in preparation for probing.
5571  *
5572  *	LOCKING:
5573  *	Inherited from caller.
5574  */
5575 void ata_dev_init(struct ata_device *dev)
5576 {
5577 	struct ata_link *link = ata_dev_phys_link(dev);
5578 	struct ata_port *ap = link->ap;
5579 	unsigned long flags;
5580 
5581 	/* SATA spd limit is bound to the attached device, reset together */
5582 	link->sata_spd_limit = link->hw_sata_spd_limit;
5583 	link->sata_spd = 0;
5584 
5585 	/* High bits of dev->flags are used to record warm plug
5586 	 * requests which occur asynchronously.  Synchronize using
5587 	 * host lock.
5588 	 */
5589 	spin_lock_irqsave(ap->lock, flags);
5590 	dev->flags &= ~ATA_DFLAG_INIT_MASK;
5591 	dev->horkage = 0;
5592 	spin_unlock_irqrestore(ap->lock, flags);
5593 
5594 	memset((void *)dev + ATA_DEVICE_CLEAR_BEGIN, 0,
5595 	       ATA_DEVICE_CLEAR_END - ATA_DEVICE_CLEAR_BEGIN);
5596 	dev->pio_mask = UINT_MAX;
5597 	dev->mwdma_mask = UINT_MAX;
5598 	dev->udma_mask = UINT_MAX;
5599 }
5600 
5601 /**
5602  *	ata_link_init - Initialize an ata_link structure
5603  *	@ap: ATA port link is attached to
5604  *	@link: Link structure to initialize
5605  *	@pmp: Port multiplier port number
5606  *
5607  *	Initialize @link.
5608  *
5609  *	LOCKING:
5610  *	Kernel thread context (may sleep)
5611  */
5612 void ata_link_init(struct ata_port *ap, struct ata_link *link, int pmp)
5613 {
5614 	int i;
5615 
5616 	/* clear everything except for devices */
5617 	memset((void *)link + ATA_LINK_CLEAR_BEGIN, 0,
5618 	       ATA_LINK_CLEAR_END - ATA_LINK_CLEAR_BEGIN);
5619 
5620 	link->ap = ap;
5621 	link->pmp = pmp;
5622 	link->active_tag = ATA_TAG_POISON;
5623 	link->hw_sata_spd_limit = UINT_MAX;
5624 
5625 	/* can't use iterator, ap isn't initialized yet */
5626 	for (i = 0; i < ATA_MAX_DEVICES; i++) {
5627 		struct ata_device *dev = &link->device[i];
5628 
5629 		dev->link = link;
5630 		dev->devno = dev - link->device;
5631 #ifdef CONFIG_ATA_ACPI
5632 		dev->gtf_filter = ata_acpi_gtf_filter;
5633 #endif
5634 		ata_dev_init(dev);
5635 	}
5636 }
5637 
5638 /**
5639  *	sata_link_init_spd - Initialize link->sata_spd_limit
5640  *	@link: Link to configure sata_spd_limit for
5641  *
5642  *	Initialize @link->[hw_]sata_spd_limit to the currently
5643  *	configured value.
5644  *
5645  *	LOCKING:
5646  *	Kernel thread context (may sleep).
5647  *
5648  *	RETURNS:
5649  *	0 on success, -errno on failure.
5650  */
5651 int sata_link_init_spd(struct ata_link *link)
5652 {
5653 	u8 spd;
5654 	int rc;
5655 
5656 	rc = sata_scr_read(link, SCR_CONTROL, &link->saved_scontrol);
5657 	if (rc)
5658 		return rc;
5659 
5660 	spd = (link->saved_scontrol >> 4) & 0xf;
5661 	if (spd)
5662 		link->hw_sata_spd_limit &= (1 << spd) - 1;
5663 
5664 	ata_force_link_limits(link);
5665 
5666 	link->sata_spd_limit = link->hw_sata_spd_limit;
5667 
5668 	return 0;
5669 }
5670 
5671 /**
5672  *	ata_port_alloc - allocate and initialize basic ATA port resources
5673  *	@host: ATA host this allocated port belongs to
5674  *
5675  *	Allocate and initialize basic ATA port resources.
5676  *
5677  *	RETURNS:
5678  *	Allocate ATA port on success, NULL on failure.
5679  *
5680  *	LOCKING:
5681  *	Inherited from calling layer (may sleep).
5682  */
5683 struct ata_port *ata_port_alloc(struct ata_host *host)
5684 {
5685 	struct ata_port *ap;
5686 
5687 	DPRINTK("ENTER\n");
5688 
5689 	ap = kzalloc(sizeof(*ap), GFP_KERNEL);
5690 	if (!ap)
5691 		return NULL;
5692 
5693 	ap->pflags |= ATA_PFLAG_INITIALIZING | ATA_PFLAG_FROZEN;
5694 	ap->lock = &host->lock;
5695 	ap->print_id = -1;
5696 	ap->local_port_no = -1;
5697 	ap->host = host;
5698 	ap->dev = host->dev;
5699 
5700 #if defined(ATA_VERBOSE_DEBUG)
5701 	/* turn on all debugging levels */
5702 	ap->msg_enable = 0x00FF;
5703 #elif defined(ATA_DEBUG)
5704 	ap->msg_enable = ATA_MSG_DRV | ATA_MSG_INFO | ATA_MSG_CTL | ATA_MSG_WARN | ATA_MSG_ERR;
5705 #else
5706 	ap->msg_enable = ATA_MSG_DRV | ATA_MSG_ERR | ATA_MSG_WARN;
5707 #endif
5708 
5709 	mutex_init(&ap->scsi_scan_mutex);
5710 	INIT_DELAYED_WORK(&ap->hotplug_task, ata_scsi_hotplug);
5711 	INIT_WORK(&ap->scsi_rescan_task, ata_scsi_dev_rescan);
5712 	INIT_LIST_HEAD(&ap->eh_done_q);
5713 	init_waitqueue_head(&ap->eh_wait_q);
5714 	init_completion(&ap->park_req_pending);
5715 	init_timer_deferrable(&ap->fastdrain_timer);
5716 	ap->fastdrain_timer.function = ata_eh_fastdrain_timerfn;
5717 	ap->fastdrain_timer.data = (unsigned long)ap;
5718 
5719 	ap->cbl = ATA_CBL_NONE;
5720 
5721 	ata_link_init(ap, &ap->link, 0);
5722 
5723 #ifdef ATA_IRQ_TRAP
5724 	ap->stats.unhandled_irq = 1;
5725 	ap->stats.idle_irq = 1;
5726 #endif
5727 	ata_sff_port_init(ap);
5728 
5729 	return ap;
5730 }
5731 
5732 static void ata_host_release(struct device *gendev, void *res)
5733 {
5734 	struct ata_host *host = dev_get_drvdata(gendev);
5735 	int i;
5736 
5737 	for (i = 0; i < host->n_ports; i++) {
5738 		struct ata_port *ap = host->ports[i];
5739 
5740 		if (!ap)
5741 			continue;
5742 
5743 		if (ap->scsi_host)
5744 			scsi_host_put(ap->scsi_host);
5745 
5746 		kfree(ap->pmp_link);
5747 		kfree(ap->slave_link);
5748 		kfree(ap);
5749 		host->ports[i] = NULL;
5750 	}
5751 
5752 	dev_set_drvdata(gendev, NULL);
5753 }
5754 
5755 /**
5756  *	ata_host_alloc - allocate and init basic ATA host resources
5757  *	@dev: generic device this host is associated with
5758  *	@max_ports: maximum number of ATA ports associated with this host
5759  *
5760  *	Allocate and initialize basic ATA host resources.  LLD calls
5761  *	this function to allocate a host, initializes it fully and
5762  *	attaches it using ata_host_register().
5763  *
5764  *	@max_ports ports are allocated and host->n_ports is
5765  *	initialized to @max_ports.  The caller is allowed to decrease
5766  *	host->n_ports before calling ata_host_register().  The unused
5767  *	ports will be automatically freed on registration.
5768  *
5769  *	RETURNS:
5770  *	Allocate ATA host on success, NULL on failure.
5771  *
5772  *	LOCKING:
5773  *	Inherited from calling layer (may sleep).
5774  */
5775 struct ata_host *ata_host_alloc(struct device *dev, int max_ports)
5776 {
5777 	struct ata_host *host;
5778 	size_t sz;
5779 	int i;
5780 
5781 	DPRINTK("ENTER\n");
5782 
5783 	if (!devres_open_group(dev, NULL, GFP_KERNEL))
5784 		return NULL;
5785 
5786 	/* alloc a container for our list of ATA ports (buses) */
5787 	sz = sizeof(struct ata_host) + (max_ports + 1) * sizeof(void *);
5788 	/* alloc a container for our list of ATA ports (buses) */
5789 	host = devres_alloc(ata_host_release, sz, GFP_KERNEL);
5790 	if (!host)
5791 		goto err_out;
5792 
5793 	devres_add(dev, host);
5794 	dev_set_drvdata(dev, host);
5795 
5796 	spin_lock_init(&host->lock);
5797 	mutex_init(&host->eh_mutex);
5798 	host->dev = dev;
5799 	host->n_ports = max_ports;
5800 
5801 	/* allocate ports bound to this host */
5802 	for (i = 0; i < max_ports; i++) {
5803 		struct ata_port *ap;
5804 
5805 		ap = ata_port_alloc(host);
5806 		if (!ap)
5807 			goto err_out;
5808 
5809 		ap->port_no = i;
5810 		host->ports[i] = ap;
5811 	}
5812 
5813 	devres_remove_group(dev, NULL);
5814 	return host;
5815 
5816  err_out:
5817 	devres_release_group(dev, NULL);
5818 	return NULL;
5819 }
5820 
5821 /**
5822  *	ata_host_alloc_pinfo - alloc host and init with port_info array
5823  *	@dev: generic device this host is associated with
5824  *	@ppi: array of ATA port_info to initialize host with
5825  *	@n_ports: number of ATA ports attached to this host
5826  *
5827  *	Allocate ATA host and initialize with info from @ppi.  If NULL
5828  *	terminated, @ppi may contain fewer entries than @n_ports.  The
5829  *	last entry will be used for the remaining ports.
5830  *
5831  *	RETURNS:
5832  *	Allocate ATA host on success, NULL on failure.
5833  *
5834  *	LOCKING:
5835  *	Inherited from calling layer (may sleep).
5836  */
5837 struct ata_host *ata_host_alloc_pinfo(struct device *dev,
5838 				      const struct ata_port_info * const * ppi,
5839 				      int n_ports)
5840 {
5841 	const struct ata_port_info *pi;
5842 	struct ata_host *host;
5843 	int i, j;
5844 
5845 	host = ata_host_alloc(dev, n_ports);
5846 	if (!host)
5847 		return NULL;
5848 
5849 	for (i = 0, j = 0, pi = NULL; i < host->n_ports; i++) {
5850 		struct ata_port *ap = host->ports[i];
5851 
5852 		if (ppi[j])
5853 			pi = ppi[j++];
5854 
5855 		ap->pio_mask = pi->pio_mask;
5856 		ap->mwdma_mask = pi->mwdma_mask;
5857 		ap->udma_mask = pi->udma_mask;
5858 		ap->flags |= pi->flags;
5859 		ap->link.flags |= pi->link_flags;
5860 		ap->ops = pi->port_ops;
5861 
5862 		if (!host->ops && (pi->port_ops != &ata_dummy_port_ops))
5863 			host->ops = pi->port_ops;
5864 	}
5865 
5866 	return host;
5867 }
5868 
5869 /**
5870  *	ata_slave_link_init - initialize slave link
5871  *	@ap: port to initialize slave link for
5872  *
5873  *	Create and initialize slave link for @ap.  This enables slave
5874  *	link handling on the port.
5875  *
5876  *	In libata, a port contains links and a link contains devices.
5877  *	There is single host link but if a PMP is attached to it,
5878  *	there can be multiple fan-out links.  On SATA, there's usually
5879  *	a single device connected to a link but PATA and SATA
5880  *	controllers emulating TF based interface can have two - master
5881  *	and slave.
5882  *
5883  *	However, there are a few controllers which don't fit into this
5884  *	abstraction too well - SATA controllers which emulate TF
5885  *	interface with both master and slave devices but also have
5886  *	separate SCR register sets for each device.  These controllers
5887  *	need separate links for physical link handling
5888  *	(e.g. onlineness, link speed) but should be treated like a
5889  *	traditional M/S controller for everything else (e.g. command
5890  *	issue, softreset).
5891  *
5892  *	slave_link is libata's way of handling this class of
5893  *	controllers without impacting core layer too much.  For
5894  *	anything other than physical link handling, the default host
5895  *	link is used for both master and slave.  For physical link
5896  *	handling, separate @ap->slave_link is used.  All dirty details
5897  *	are implemented inside libata core layer.  From LLD's POV, the
5898  *	only difference is that prereset, hardreset and postreset are
5899  *	called once more for the slave link, so the reset sequence
5900  *	looks like the following.
5901  *
5902  *	prereset(M) -> prereset(S) -> hardreset(M) -> hardreset(S) ->
5903  *	softreset(M) -> postreset(M) -> postreset(S)
5904  *
5905  *	Note that softreset is called only for the master.  Softreset
5906  *	resets both M/S by definition, so SRST on master should handle
5907  *	both (the standard method will work just fine).
5908  *
5909  *	LOCKING:
5910  *	Should be called before host is registered.
5911  *
5912  *	RETURNS:
5913  *	0 on success, -errno on failure.
5914  */
5915 int ata_slave_link_init(struct ata_port *ap)
5916 {
5917 	struct ata_link *link;
5918 
5919 	WARN_ON(ap->slave_link);
5920 	WARN_ON(ap->flags & ATA_FLAG_PMP);
5921 
5922 	link = kzalloc(sizeof(*link), GFP_KERNEL);
5923 	if (!link)
5924 		return -ENOMEM;
5925 
5926 	ata_link_init(ap, link, 1);
5927 	ap->slave_link = link;
5928 	return 0;
5929 }
5930 
5931 static void ata_host_stop(struct device *gendev, void *res)
5932 {
5933 	struct ata_host *host = dev_get_drvdata(gendev);
5934 	int i;
5935 
5936 	WARN_ON(!(host->flags & ATA_HOST_STARTED));
5937 
5938 	for (i = 0; i < host->n_ports; i++) {
5939 		struct ata_port *ap = host->ports[i];
5940 
5941 		if (ap->ops->port_stop)
5942 			ap->ops->port_stop(ap);
5943 	}
5944 
5945 	if (host->ops->host_stop)
5946 		host->ops->host_stop(host);
5947 }
5948 
5949 /**
5950  *	ata_finalize_port_ops - finalize ata_port_operations
5951  *	@ops: ata_port_operations to finalize
5952  *
5953  *	An ata_port_operations can inherit from another ops and that
5954  *	ops can again inherit from another.  This can go on as many
5955  *	times as necessary as long as there is no loop in the
5956  *	inheritance chain.
5957  *
5958  *	Ops tables are finalized when the host is started.  NULL or
5959  *	unspecified entries are inherited from the closet ancestor
5960  *	which has the method and the entry is populated with it.
5961  *	After finalization, the ops table directly points to all the
5962  *	methods and ->inherits is no longer necessary and cleared.
5963  *
5964  *	Using ATA_OP_NULL, inheriting ops can force a method to NULL.
5965  *
5966  *	LOCKING:
5967  *	None.
5968  */
5969 static void ata_finalize_port_ops(struct ata_port_operations *ops)
5970 {
5971 	static DEFINE_SPINLOCK(lock);
5972 	const struct ata_port_operations *cur;
5973 	void **begin = (void **)ops;
5974 	void **end = (void **)&ops->inherits;
5975 	void **pp;
5976 
5977 	if (!ops || !ops->inherits)
5978 		return;
5979 
5980 	spin_lock(&lock);
5981 
5982 	for (cur = ops->inherits; cur; cur = cur->inherits) {
5983 		void **inherit = (void **)cur;
5984 
5985 		for (pp = begin; pp < end; pp++, inherit++)
5986 			if (!*pp)
5987 				*pp = *inherit;
5988 	}
5989 
5990 	for (pp = begin; pp < end; pp++)
5991 		if (IS_ERR(*pp))
5992 			*pp = NULL;
5993 
5994 	ops->inherits = NULL;
5995 
5996 	spin_unlock(&lock);
5997 }
5998 
5999 /**
6000  *	ata_host_start - start and freeze ports of an ATA host
6001  *	@host: ATA host to start ports for
6002  *
6003  *	Start and then freeze ports of @host.  Started status is
6004  *	recorded in host->flags, so this function can be called
6005  *	multiple times.  Ports are guaranteed to get started only
6006  *	once.  If host->ops isn't initialized yet, its set to the
6007  *	first non-dummy port ops.
6008  *
6009  *	LOCKING:
6010  *	Inherited from calling layer (may sleep).
6011  *
6012  *	RETURNS:
6013  *	0 if all ports are started successfully, -errno otherwise.
6014  */
6015 int ata_host_start(struct ata_host *host)
6016 {
6017 	int have_stop = 0;
6018 	void *start_dr = NULL;
6019 	int i, rc;
6020 
6021 	if (host->flags & ATA_HOST_STARTED)
6022 		return 0;
6023 
6024 	ata_finalize_port_ops(host->ops);
6025 
6026 	for (i = 0; i < host->n_ports; i++) {
6027 		struct ata_port *ap = host->ports[i];
6028 
6029 		ata_finalize_port_ops(ap->ops);
6030 
6031 		if (!host->ops && !ata_port_is_dummy(ap))
6032 			host->ops = ap->ops;
6033 
6034 		if (ap->ops->port_stop)
6035 			have_stop = 1;
6036 	}
6037 
6038 	if (host->ops->host_stop)
6039 		have_stop = 1;
6040 
6041 	if (have_stop) {
6042 		start_dr = devres_alloc(ata_host_stop, 0, GFP_KERNEL);
6043 		if (!start_dr)
6044 			return -ENOMEM;
6045 	}
6046 
6047 	for (i = 0; i < host->n_ports; i++) {
6048 		struct ata_port *ap = host->ports[i];
6049 
6050 		if (ap->ops->port_start) {
6051 			rc = ap->ops->port_start(ap);
6052 			if (rc) {
6053 				if (rc != -ENODEV)
6054 					dev_err(host->dev,
6055 						"failed to start port %d (errno=%d)\n",
6056 						i, rc);
6057 				goto err_out;
6058 			}
6059 		}
6060 		ata_eh_freeze_port(ap);
6061 	}
6062 
6063 	if (start_dr)
6064 		devres_add(host->dev, start_dr);
6065 	host->flags |= ATA_HOST_STARTED;
6066 	return 0;
6067 
6068  err_out:
6069 	while (--i >= 0) {
6070 		struct ata_port *ap = host->ports[i];
6071 
6072 		if (ap->ops->port_stop)
6073 			ap->ops->port_stop(ap);
6074 	}
6075 	devres_free(start_dr);
6076 	return rc;
6077 }
6078 
6079 /**
6080  *	ata_sas_host_init - Initialize a host struct for sas (ipr, libsas)
6081  *	@host:	host to initialize
6082  *	@dev:	device host is attached to
6083  *	@ops:	port_ops
6084  *
6085  */
6086 void ata_host_init(struct ata_host *host, struct device *dev,
6087 		   struct ata_port_operations *ops)
6088 {
6089 	spin_lock_init(&host->lock);
6090 	mutex_init(&host->eh_mutex);
6091 	host->dev = dev;
6092 	host->ops = ops;
6093 }
6094 
6095 void __ata_port_probe(struct ata_port *ap)
6096 {
6097 	struct ata_eh_info *ehi = &ap->link.eh_info;
6098 	unsigned long flags;
6099 
6100 	/* kick EH for boot probing */
6101 	spin_lock_irqsave(ap->lock, flags);
6102 
6103 	ehi->probe_mask |= ATA_ALL_DEVICES;
6104 	ehi->action |= ATA_EH_RESET;
6105 	ehi->flags |= ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET;
6106 
6107 	ap->pflags &= ~ATA_PFLAG_INITIALIZING;
6108 	ap->pflags |= ATA_PFLAG_LOADING;
6109 	ata_port_schedule_eh(ap);
6110 
6111 	spin_unlock_irqrestore(ap->lock, flags);
6112 }
6113 
6114 int ata_port_probe(struct ata_port *ap)
6115 {
6116 	int rc = 0;
6117 
6118 	if (ap->ops->error_handler) {
6119 		__ata_port_probe(ap);
6120 		ata_port_wait_eh(ap);
6121 	} else {
6122 		DPRINTK("ata%u: bus probe begin\n", ap->print_id);
6123 		rc = ata_bus_probe(ap);
6124 		DPRINTK("ata%u: bus probe end\n", ap->print_id);
6125 	}
6126 	return rc;
6127 }
6128 
6129 
6130 static void async_port_probe(void *data, async_cookie_t cookie)
6131 {
6132 	struct ata_port *ap = data;
6133 
6134 	/*
6135 	 * If we're not allowed to scan this host in parallel,
6136 	 * we need to wait until all previous scans have completed
6137 	 * before going further.
6138 	 * Jeff Garzik says this is only within a controller, so we
6139 	 * don't need to wait for port 0, only for later ports.
6140 	 */
6141 	if (!(ap->host->flags & ATA_HOST_PARALLEL_SCAN) && ap->port_no != 0)
6142 		async_synchronize_cookie(cookie);
6143 
6144 	(void)ata_port_probe(ap);
6145 
6146 	/* in order to keep device order, we need to synchronize at this point */
6147 	async_synchronize_cookie(cookie);
6148 
6149 	ata_scsi_scan_host(ap, 1);
6150 }
6151 
6152 /**
6153  *	ata_host_register - register initialized ATA host
6154  *	@host: ATA host to register
6155  *	@sht: template for SCSI host
6156  *
6157  *	Register initialized ATA host.  @host is allocated using
6158  *	ata_host_alloc() and fully initialized by LLD.  This function
6159  *	starts ports, registers @host with ATA and SCSI layers and
6160  *	probe registered devices.
6161  *
6162  *	LOCKING:
6163  *	Inherited from calling layer (may sleep).
6164  *
6165  *	RETURNS:
6166  *	0 on success, -errno otherwise.
6167  */
6168 int ata_host_register(struct ata_host *host, struct scsi_host_template *sht)
6169 {
6170 	int i, rc;
6171 
6172 	/* host must have been started */
6173 	if (!(host->flags & ATA_HOST_STARTED)) {
6174 		dev_err(host->dev, "BUG: trying to register unstarted host\n");
6175 		WARN_ON(1);
6176 		return -EINVAL;
6177 	}
6178 
6179 	/* Blow away unused ports.  This happens when LLD can't
6180 	 * determine the exact number of ports to allocate at
6181 	 * allocation time.
6182 	 */
6183 	for (i = host->n_ports; host->ports[i]; i++)
6184 		kfree(host->ports[i]);
6185 
6186 	/* give ports names and add SCSI hosts */
6187 	for (i = 0; i < host->n_ports; i++) {
6188 		host->ports[i]->print_id = atomic_inc_return(&ata_print_id);
6189 		host->ports[i]->local_port_no = i + 1;
6190 	}
6191 
6192 	/* Create associated sysfs transport objects  */
6193 	for (i = 0; i < host->n_ports; i++) {
6194 		rc = ata_tport_add(host->dev,host->ports[i]);
6195 		if (rc) {
6196 			goto err_tadd;
6197 		}
6198 	}
6199 
6200 	rc = ata_scsi_add_hosts(host, sht);
6201 	if (rc)
6202 		goto err_tadd;
6203 
6204 	/* set cable, sata_spd_limit and report */
6205 	for (i = 0; i < host->n_ports; i++) {
6206 		struct ata_port *ap = host->ports[i];
6207 		unsigned long xfer_mask;
6208 
6209 		/* set SATA cable type if still unset */
6210 		if (ap->cbl == ATA_CBL_NONE && (ap->flags & ATA_FLAG_SATA))
6211 			ap->cbl = ATA_CBL_SATA;
6212 
6213 		/* init sata_spd_limit to the current value */
6214 		sata_link_init_spd(&ap->link);
6215 		if (ap->slave_link)
6216 			sata_link_init_spd(ap->slave_link);
6217 
6218 		/* print per-port info to dmesg */
6219 		xfer_mask = ata_pack_xfermask(ap->pio_mask, ap->mwdma_mask,
6220 					      ap->udma_mask);
6221 
6222 		if (!ata_port_is_dummy(ap)) {
6223 			ata_port_info(ap, "%cATA max %s %s\n",
6224 				      (ap->flags & ATA_FLAG_SATA) ? 'S' : 'P',
6225 				      ata_mode_string(xfer_mask),
6226 				      ap->link.eh_info.desc);
6227 			ata_ehi_clear_desc(&ap->link.eh_info);
6228 		} else
6229 			ata_port_info(ap, "DUMMY\n");
6230 	}
6231 
6232 	/* perform each probe asynchronously */
6233 	for (i = 0; i < host->n_ports; i++) {
6234 		struct ata_port *ap = host->ports[i];
6235 		async_schedule(async_port_probe, ap);
6236 	}
6237 
6238 	return 0;
6239 
6240  err_tadd:
6241 	while (--i >= 0) {
6242 		ata_tport_delete(host->ports[i]);
6243 	}
6244 	return rc;
6245 
6246 }
6247 
6248 /**
6249  *	ata_host_activate - start host, request IRQ and register it
6250  *	@host: target ATA host
6251  *	@irq: IRQ to request
6252  *	@irq_handler: irq_handler used when requesting IRQ
6253  *	@irq_flags: irq_flags used when requesting IRQ
6254  *	@sht: scsi_host_template to use when registering the host
6255  *
6256  *	After allocating an ATA host and initializing it, most libata
6257  *	LLDs perform three steps to activate the host - start host,
6258  *	request IRQ and register it.  This helper takes necessasry
6259  *	arguments and performs the three steps in one go.
6260  *
6261  *	An invalid IRQ skips the IRQ registration and expects the host to
6262  *	have set polling mode on the port. In this case, @irq_handler
6263  *	should be NULL.
6264  *
6265  *	LOCKING:
6266  *	Inherited from calling layer (may sleep).
6267  *
6268  *	RETURNS:
6269  *	0 on success, -errno otherwise.
6270  */
6271 int ata_host_activate(struct ata_host *host, int irq,
6272 		      irq_handler_t irq_handler, unsigned long irq_flags,
6273 		      struct scsi_host_template *sht)
6274 {
6275 	int i, rc;
6276 
6277 	rc = ata_host_start(host);
6278 	if (rc)
6279 		return rc;
6280 
6281 	/* Special case for polling mode */
6282 	if (!irq) {
6283 		WARN_ON(irq_handler);
6284 		return ata_host_register(host, sht);
6285 	}
6286 
6287 	rc = devm_request_irq(host->dev, irq, irq_handler, irq_flags,
6288 			      dev_driver_string(host->dev), host);
6289 	if (rc)
6290 		return rc;
6291 
6292 	for (i = 0; i < host->n_ports; i++)
6293 		ata_port_desc(host->ports[i], "irq %d", irq);
6294 
6295 	rc = ata_host_register(host, sht);
6296 	/* if failed, just free the IRQ and leave ports alone */
6297 	if (rc)
6298 		devm_free_irq(host->dev, irq, host);
6299 
6300 	return rc;
6301 }
6302 
6303 /**
6304  *	ata_port_detach - Detach ATA port in prepration of device removal
6305  *	@ap: ATA port to be detached
6306  *
6307  *	Detach all ATA devices and the associated SCSI devices of @ap;
6308  *	then, remove the associated SCSI host.  @ap is guaranteed to
6309  *	be quiescent on return from this function.
6310  *
6311  *	LOCKING:
6312  *	Kernel thread context (may sleep).
6313  */
6314 static void ata_port_detach(struct ata_port *ap)
6315 {
6316 	unsigned long flags;
6317 	struct ata_link *link;
6318 	struct ata_device *dev;
6319 
6320 	if (!ap->ops->error_handler)
6321 		goto skip_eh;
6322 
6323 	/* tell EH we're leaving & flush EH */
6324 	spin_lock_irqsave(ap->lock, flags);
6325 	ap->pflags |= ATA_PFLAG_UNLOADING;
6326 	ata_port_schedule_eh(ap);
6327 	spin_unlock_irqrestore(ap->lock, flags);
6328 
6329 	/* wait till EH commits suicide */
6330 	ata_port_wait_eh(ap);
6331 
6332 	/* it better be dead now */
6333 	WARN_ON(!(ap->pflags & ATA_PFLAG_UNLOADED));
6334 
6335 	cancel_delayed_work_sync(&ap->hotplug_task);
6336 
6337  skip_eh:
6338 	/* clean up zpodd on port removal */
6339 	ata_for_each_link(link, ap, HOST_FIRST) {
6340 		ata_for_each_dev(dev, link, ALL) {
6341 			if (zpodd_dev_enabled(dev))
6342 				zpodd_exit(dev);
6343 		}
6344 	}
6345 	if (ap->pmp_link) {
6346 		int i;
6347 		for (i = 0; i < SATA_PMP_MAX_PORTS; i++)
6348 			ata_tlink_delete(&ap->pmp_link[i]);
6349 	}
6350 	/* remove the associated SCSI host */
6351 	scsi_remove_host(ap->scsi_host);
6352 	ata_tport_delete(ap);
6353 }
6354 
6355 /**
6356  *	ata_host_detach - Detach all ports of an ATA host
6357  *	@host: Host to detach
6358  *
6359  *	Detach all ports of @host.
6360  *
6361  *	LOCKING:
6362  *	Kernel thread context (may sleep).
6363  */
6364 void ata_host_detach(struct ata_host *host)
6365 {
6366 	int i;
6367 
6368 	for (i = 0; i < host->n_ports; i++)
6369 		ata_port_detach(host->ports[i]);
6370 
6371 	/* the host is dead now, dissociate ACPI */
6372 	ata_acpi_dissociate(host);
6373 }
6374 
6375 #ifdef CONFIG_PCI
6376 
6377 /**
6378  *	ata_pci_remove_one - PCI layer callback for device removal
6379  *	@pdev: PCI device that was removed
6380  *
6381  *	PCI layer indicates to libata via this hook that hot-unplug or
6382  *	module unload event has occurred.  Detach all ports.  Resource
6383  *	release is handled via devres.
6384  *
6385  *	LOCKING:
6386  *	Inherited from PCI layer (may sleep).
6387  */
6388 void ata_pci_remove_one(struct pci_dev *pdev)
6389 {
6390 	struct ata_host *host = pci_get_drvdata(pdev);
6391 
6392 	ata_host_detach(host);
6393 }
6394 
6395 /* move to PCI subsystem */
6396 int pci_test_config_bits(struct pci_dev *pdev, const struct pci_bits *bits)
6397 {
6398 	unsigned long tmp = 0;
6399 
6400 	switch (bits->width) {
6401 	case 1: {
6402 		u8 tmp8 = 0;
6403 		pci_read_config_byte(pdev, bits->reg, &tmp8);
6404 		tmp = tmp8;
6405 		break;
6406 	}
6407 	case 2: {
6408 		u16 tmp16 = 0;
6409 		pci_read_config_word(pdev, bits->reg, &tmp16);
6410 		tmp = tmp16;
6411 		break;
6412 	}
6413 	case 4: {
6414 		u32 tmp32 = 0;
6415 		pci_read_config_dword(pdev, bits->reg, &tmp32);
6416 		tmp = tmp32;
6417 		break;
6418 	}
6419 
6420 	default:
6421 		return -EINVAL;
6422 	}
6423 
6424 	tmp &= bits->mask;
6425 
6426 	return (tmp == bits->val) ? 1 : 0;
6427 }
6428 
6429 #ifdef CONFIG_PM
6430 void ata_pci_device_do_suspend(struct pci_dev *pdev, pm_message_t mesg)
6431 {
6432 	pci_save_state(pdev);
6433 	pci_disable_device(pdev);
6434 
6435 	if (mesg.event & PM_EVENT_SLEEP)
6436 		pci_set_power_state(pdev, PCI_D3hot);
6437 }
6438 
6439 int ata_pci_device_do_resume(struct pci_dev *pdev)
6440 {
6441 	int rc;
6442 
6443 	pci_set_power_state(pdev, PCI_D0);
6444 	pci_restore_state(pdev);
6445 
6446 	rc = pcim_enable_device(pdev);
6447 	if (rc) {
6448 		dev_err(&pdev->dev,
6449 			"failed to enable device after resume (%d)\n", rc);
6450 		return rc;
6451 	}
6452 
6453 	pci_set_master(pdev);
6454 	return 0;
6455 }
6456 
6457 int ata_pci_device_suspend(struct pci_dev *pdev, pm_message_t mesg)
6458 {
6459 	struct ata_host *host = pci_get_drvdata(pdev);
6460 	int rc = 0;
6461 
6462 	rc = ata_host_suspend(host, mesg);
6463 	if (rc)
6464 		return rc;
6465 
6466 	ata_pci_device_do_suspend(pdev, mesg);
6467 
6468 	return 0;
6469 }
6470 
6471 int ata_pci_device_resume(struct pci_dev *pdev)
6472 {
6473 	struct ata_host *host = pci_get_drvdata(pdev);
6474 	int rc;
6475 
6476 	rc = ata_pci_device_do_resume(pdev);
6477 	if (rc == 0)
6478 		ata_host_resume(host);
6479 	return rc;
6480 }
6481 #endif /* CONFIG_PM */
6482 
6483 #endif /* CONFIG_PCI */
6484 
6485 /**
6486  *	ata_platform_remove_one - Platform layer callback for device removal
6487  *	@pdev: Platform device that was removed
6488  *
6489  *	Platform layer indicates to libata via this hook that hot-unplug or
6490  *	module unload event has occurred.  Detach all ports.  Resource
6491  *	release is handled via devres.
6492  *
6493  *	LOCKING:
6494  *	Inherited from platform layer (may sleep).
6495  */
6496 int ata_platform_remove_one(struct platform_device *pdev)
6497 {
6498 	struct ata_host *host = platform_get_drvdata(pdev);
6499 
6500 	ata_host_detach(host);
6501 
6502 	return 0;
6503 }
6504 
6505 static int __init ata_parse_force_one(char **cur,
6506 				      struct ata_force_ent *force_ent,
6507 				      const char **reason)
6508 {
6509 	/* FIXME: Currently, there's no way to tag init const data and
6510 	 * using __initdata causes build failure on some versions of
6511 	 * gcc.  Once __initdataconst is implemented, add const to the
6512 	 * following structure.
6513 	 */
6514 	static struct ata_force_param force_tbl[] __initdata = {
6515 		{ "40c",	.cbl		= ATA_CBL_PATA40 },
6516 		{ "80c",	.cbl		= ATA_CBL_PATA80 },
6517 		{ "short40c",	.cbl		= ATA_CBL_PATA40_SHORT },
6518 		{ "unk",	.cbl		= ATA_CBL_PATA_UNK },
6519 		{ "ign",	.cbl		= ATA_CBL_PATA_IGN },
6520 		{ "sata",	.cbl		= ATA_CBL_SATA },
6521 		{ "1.5Gbps",	.spd_limit	= 1 },
6522 		{ "3.0Gbps",	.spd_limit	= 2 },
6523 		{ "noncq",	.horkage_on	= ATA_HORKAGE_NONCQ },
6524 		{ "ncq",	.horkage_off	= ATA_HORKAGE_NONCQ },
6525 		{ "dump_id",	.horkage_on	= ATA_HORKAGE_DUMP_ID },
6526 		{ "pio0",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 0) },
6527 		{ "pio1",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 1) },
6528 		{ "pio2",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 2) },
6529 		{ "pio3",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 3) },
6530 		{ "pio4",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 4) },
6531 		{ "pio5",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 5) },
6532 		{ "pio6",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 6) },
6533 		{ "mwdma0",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 0) },
6534 		{ "mwdma1",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 1) },
6535 		{ "mwdma2",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 2) },
6536 		{ "mwdma3",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 3) },
6537 		{ "mwdma4",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 4) },
6538 		{ "udma0",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 0) },
6539 		{ "udma16",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 0) },
6540 		{ "udma/16",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 0) },
6541 		{ "udma1",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 1) },
6542 		{ "udma25",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 1) },
6543 		{ "udma/25",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 1) },
6544 		{ "udma2",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 2) },
6545 		{ "udma33",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 2) },
6546 		{ "udma/33",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 2) },
6547 		{ "udma3",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 3) },
6548 		{ "udma44",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 3) },
6549 		{ "udma/44",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 3) },
6550 		{ "udma4",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 4) },
6551 		{ "udma66",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 4) },
6552 		{ "udma/66",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 4) },
6553 		{ "udma5",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 5) },
6554 		{ "udma100",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 5) },
6555 		{ "udma/100",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 5) },
6556 		{ "udma6",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 6) },
6557 		{ "udma133",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 6) },
6558 		{ "udma/133",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 6) },
6559 		{ "udma7",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 7) },
6560 		{ "nohrst",	.lflags		= ATA_LFLAG_NO_HRST },
6561 		{ "nosrst",	.lflags		= ATA_LFLAG_NO_SRST },
6562 		{ "norst",	.lflags		= ATA_LFLAG_NO_HRST | ATA_LFLAG_NO_SRST },
6563 		{ "rstonce",	.lflags		= ATA_LFLAG_RST_ONCE },
6564 		{ "atapi_dmadir", .horkage_on	= ATA_HORKAGE_ATAPI_DMADIR },
6565 		{ "disable",	.horkage_on	= ATA_HORKAGE_DISABLE },
6566 	};
6567 	char *start = *cur, *p = *cur;
6568 	char *id, *val, *endp;
6569 	const struct ata_force_param *match_fp = NULL;
6570 	int nr_matches = 0, i;
6571 
6572 	/* find where this param ends and update *cur */
6573 	while (*p != '\0' && *p != ',')
6574 		p++;
6575 
6576 	if (*p == '\0')
6577 		*cur = p;
6578 	else
6579 		*cur = p + 1;
6580 
6581 	*p = '\0';
6582 
6583 	/* parse */
6584 	p = strchr(start, ':');
6585 	if (!p) {
6586 		val = strstrip(start);
6587 		goto parse_val;
6588 	}
6589 	*p = '\0';
6590 
6591 	id = strstrip(start);
6592 	val = strstrip(p + 1);
6593 
6594 	/* parse id */
6595 	p = strchr(id, '.');
6596 	if (p) {
6597 		*p++ = '\0';
6598 		force_ent->device = simple_strtoul(p, &endp, 10);
6599 		if (p == endp || *endp != '\0') {
6600 			*reason = "invalid device";
6601 			return -EINVAL;
6602 		}
6603 	}
6604 
6605 	force_ent->port = simple_strtoul(id, &endp, 10);
6606 	if (p == endp || *endp != '\0') {
6607 		*reason = "invalid port/link";
6608 		return -EINVAL;
6609 	}
6610 
6611  parse_val:
6612 	/* parse val, allow shortcuts so that both 1.5 and 1.5Gbps work */
6613 	for (i = 0; i < ARRAY_SIZE(force_tbl); i++) {
6614 		const struct ata_force_param *fp = &force_tbl[i];
6615 
6616 		if (strncasecmp(val, fp->name, strlen(val)))
6617 			continue;
6618 
6619 		nr_matches++;
6620 		match_fp = fp;
6621 
6622 		if (strcasecmp(val, fp->name) == 0) {
6623 			nr_matches = 1;
6624 			break;
6625 		}
6626 	}
6627 
6628 	if (!nr_matches) {
6629 		*reason = "unknown value";
6630 		return -EINVAL;
6631 	}
6632 	if (nr_matches > 1) {
6633 		*reason = "ambigious value";
6634 		return -EINVAL;
6635 	}
6636 
6637 	force_ent->param = *match_fp;
6638 
6639 	return 0;
6640 }
6641 
6642 static void __init ata_parse_force_param(void)
6643 {
6644 	int idx = 0, size = 1;
6645 	int last_port = -1, last_device = -1;
6646 	char *p, *cur, *next;
6647 
6648 	/* calculate maximum number of params and allocate force_tbl */
6649 	for (p = ata_force_param_buf; *p; p++)
6650 		if (*p == ',')
6651 			size++;
6652 
6653 	ata_force_tbl = kzalloc(sizeof(ata_force_tbl[0]) * size, GFP_KERNEL);
6654 	if (!ata_force_tbl) {
6655 		printk(KERN_WARNING "ata: failed to extend force table, "
6656 		       "libata.force ignored\n");
6657 		return;
6658 	}
6659 
6660 	/* parse and populate the table */
6661 	for (cur = ata_force_param_buf; *cur != '\0'; cur = next) {
6662 		const char *reason = "";
6663 		struct ata_force_ent te = { .port = -1, .device = -1 };
6664 
6665 		next = cur;
6666 		if (ata_parse_force_one(&next, &te, &reason)) {
6667 			printk(KERN_WARNING "ata: failed to parse force "
6668 			       "parameter \"%s\" (%s)\n",
6669 			       cur, reason);
6670 			continue;
6671 		}
6672 
6673 		if (te.port == -1) {
6674 			te.port = last_port;
6675 			te.device = last_device;
6676 		}
6677 
6678 		ata_force_tbl[idx++] = te;
6679 
6680 		last_port = te.port;
6681 		last_device = te.device;
6682 	}
6683 
6684 	ata_force_tbl_size = idx;
6685 }
6686 
6687 static int __init ata_init(void)
6688 {
6689 	int rc;
6690 
6691 	ata_parse_force_param();
6692 
6693 	rc = ata_sff_init();
6694 	if (rc) {
6695 		kfree(ata_force_tbl);
6696 		return rc;
6697 	}
6698 
6699 	libata_transport_init();
6700 	ata_scsi_transport_template = ata_attach_transport();
6701 	if (!ata_scsi_transport_template) {
6702 		ata_sff_exit();
6703 		rc = -ENOMEM;
6704 		goto err_out;
6705 	}
6706 
6707 	printk(KERN_DEBUG "libata version " DRV_VERSION " loaded.\n");
6708 	return 0;
6709 
6710 err_out:
6711 	return rc;
6712 }
6713 
6714 static void __exit ata_exit(void)
6715 {
6716 	ata_release_transport(ata_scsi_transport_template);
6717 	libata_transport_exit();
6718 	ata_sff_exit();
6719 	kfree(ata_force_tbl);
6720 }
6721 
6722 subsys_initcall(ata_init);
6723 module_exit(ata_exit);
6724 
6725 static DEFINE_RATELIMIT_STATE(ratelimit, HZ / 5, 1);
6726 
6727 int ata_ratelimit(void)
6728 {
6729 	return __ratelimit(&ratelimit);
6730 }
6731 
6732 /**
6733  *	ata_msleep - ATA EH owner aware msleep
6734  *	@ap: ATA port to attribute the sleep to
6735  *	@msecs: duration to sleep in milliseconds
6736  *
6737  *	Sleeps @msecs.  If the current task is owner of @ap's EH, the
6738  *	ownership is released before going to sleep and reacquired
6739  *	after the sleep is complete.  IOW, other ports sharing the
6740  *	@ap->host will be allowed to own the EH while this task is
6741  *	sleeping.
6742  *
6743  *	LOCKING:
6744  *	Might sleep.
6745  */
6746 void ata_msleep(struct ata_port *ap, unsigned int msecs)
6747 {
6748 	bool owns_eh = ap && ap->host->eh_owner == current;
6749 
6750 	if (owns_eh)
6751 		ata_eh_release(ap);
6752 
6753 	msleep(msecs);
6754 
6755 	if (owns_eh)
6756 		ata_eh_acquire(ap);
6757 }
6758 
6759 /**
6760  *	ata_wait_register - wait until register value changes
6761  *	@ap: ATA port to wait register for, can be NULL
6762  *	@reg: IO-mapped register
6763  *	@mask: Mask to apply to read register value
6764  *	@val: Wait condition
6765  *	@interval: polling interval in milliseconds
6766  *	@timeout: timeout in milliseconds
6767  *
6768  *	Waiting for some bits of register to change is a common
6769  *	operation for ATA controllers.  This function reads 32bit LE
6770  *	IO-mapped register @reg and tests for the following condition.
6771  *
6772  *	(*@reg & mask) != val
6773  *
6774  *	If the condition is met, it returns; otherwise, the process is
6775  *	repeated after @interval_msec until timeout.
6776  *
6777  *	LOCKING:
6778  *	Kernel thread context (may sleep)
6779  *
6780  *	RETURNS:
6781  *	The final register value.
6782  */
6783 u32 ata_wait_register(struct ata_port *ap, void __iomem *reg, u32 mask, u32 val,
6784 		      unsigned long interval, unsigned long timeout)
6785 {
6786 	unsigned long deadline;
6787 	u32 tmp;
6788 
6789 	tmp = ioread32(reg);
6790 
6791 	/* Calculate timeout _after_ the first read to make sure
6792 	 * preceding writes reach the controller before starting to
6793 	 * eat away the timeout.
6794 	 */
6795 	deadline = ata_deadline(jiffies, timeout);
6796 
6797 	while ((tmp & mask) == val && time_before(jiffies, deadline)) {
6798 		ata_msleep(ap, interval);
6799 		tmp = ioread32(reg);
6800 	}
6801 
6802 	return tmp;
6803 }
6804 
6805 /*
6806  * Dummy port_ops
6807  */
6808 static unsigned int ata_dummy_qc_issue(struct ata_queued_cmd *qc)
6809 {
6810 	return AC_ERR_SYSTEM;
6811 }
6812 
6813 static void ata_dummy_error_handler(struct ata_port *ap)
6814 {
6815 	/* truly dummy */
6816 }
6817 
6818 struct ata_port_operations ata_dummy_port_ops = {
6819 	.qc_prep		= ata_noop_qc_prep,
6820 	.qc_issue		= ata_dummy_qc_issue,
6821 	.error_handler		= ata_dummy_error_handler,
6822 	.sched_eh		= ata_std_sched_eh,
6823 	.end_eh			= ata_std_end_eh,
6824 };
6825 
6826 const struct ata_port_info ata_dummy_port_info = {
6827 	.port_ops		= &ata_dummy_port_ops,
6828 };
6829 
6830 /*
6831  * Utility print functions
6832  */
6833 int ata_port_printk(const struct ata_port *ap, const char *level,
6834 		    const char *fmt, ...)
6835 {
6836 	struct va_format vaf;
6837 	va_list args;
6838 	int r;
6839 
6840 	va_start(args, fmt);
6841 
6842 	vaf.fmt = fmt;
6843 	vaf.va = &args;
6844 
6845 	r = printk("%sata%u: %pV", level, ap->print_id, &vaf);
6846 
6847 	va_end(args);
6848 
6849 	return r;
6850 }
6851 EXPORT_SYMBOL(ata_port_printk);
6852 
6853 int ata_link_printk(const struct ata_link *link, const char *level,
6854 		    const char *fmt, ...)
6855 {
6856 	struct va_format vaf;
6857 	va_list args;
6858 	int r;
6859 
6860 	va_start(args, fmt);
6861 
6862 	vaf.fmt = fmt;
6863 	vaf.va = &args;
6864 
6865 	if (sata_pmp_attached(link->ap) || link->ap->slave_link)
6866 		r = printk("%sata%u.%02u: %pV",
6867 			   level, link->ap->print_id, link->pmp, &vaf);
6868 	else
6869 		r = printk("%sata%u: %pV",
6870 			   level, link->ap->print_id, &vaf);
6871 
6872 	va_end(args);
6873 
6874 	return r;
6875 }
6876 EXPORT_SYMBOL(ata_link_printk);
6877 
6878 int ata_dev_printk(const struct ata_device *dev, const char *level,
6879 		    const char *fmt, ...)
6880 {
6881 	struct va_format vaf;
6882 	va_list args;
6883 	int r;
6884 
6885 	va_start(args, fmt);
6886 
6887 	vaf.fmt = fmt;
6888 	vaf.va = &args;
6889 
6890 	r = printk("%sata%u.%02u: %pV",
6891 		   level, dev->link->ap->print_id, dev->link->pmp + dev->devno,
6892 		   &vaf);
6893 
6894 	va_end(args);
6895 
6896 	return r;
6897 }
6898 EXPORT_SYMBOL(ata_dev_printk);
6899 
6900 void ata_print_version(const struct device *dev, const char *version)
6901 {
6902 	dev_printk(KERN_DEBUG, dev, "version %s\n", version);
6903 }
6904 EXPORT_SYMBOL(ata_print_version);
6905 
6906 /*
6907  * libata is essentially a library of internal helper functions for
6908  * low-level ATA host controller drivers.  As such, the API/ABI is
6909  * likely to change as new drivers are added and updated.
6910  * Do not depend on ABI/API stability.
6911  */
6912 EXPORT_SYMBOL_GPL(sata_deb_timing_normal);
6913 EXPORT_SYMBOL_GPL(sata_deb_timing_hotplug);
6914 EXPORT_SYMBOL_GPL(sata_deb_timing_long);
6915 EXPORT_SYMBOL_GPL(ata_base_port_ops);
6916 EXPORT_SYMBOL_GPL(sata_port_ops);
6917 EXPORT_SYMBOL_GPL(ata_dummy_port_ops);
6918 EXPORT_SYMBOL_GPL(ata_dummy_port_info);
6919 EXPORT_SYMBOL_GPL(ata_link_next);
6920 EXPORT_SYMBOL_GPL(ata_dev_next);
6921 EXPORT_SYMBOL_GPL(ata_std_bios_param);
6922 EXPORT_SYMBOL_GPL(ata_scsi_unlock_native_capacity);
6923 EXPORT_SYMBOL_GPL(ata_host_init);
6924 EXPORT_SYMBOL_GPL(ata_host_alloc);
6925 EXPORT_SYMBOL_GPL(ata_host_alloc_pinfo);
6926 EXPORT_SYMBOL_GPL(ata_slave_link_init);
6927 EXPORT_SYMBOL_GPL(ata_host_start);
6928 EXPORT_SYMBOL_GPL(ata_host_register);
6929 EXPORT_SYMBOL_GPL(ata_host_activate);
6930 EXPORT_SYMBOL_GPL(ata_host_detach);
6931 EXPORT_SYMBOL_GPL(ata_sg_init);
6932 EXPORT_SYMBOL_GPL(ata_qc_complete);
6933 EXPORT_SYMBOL_GPL(ata_qc_complete_multiple);
6934 EXPORT_SYMBOL_GPL(atapi_cmd_type);
6935 EXPORT_SYMBOL_GPL(ata_tf_to_fis);
6936 EXPORT_SYMBOL_GPL(ata_tf_from_fis);
6937 EXPORT_SYMBOL_GPL(ata_pack_xfermask);
6938 EXPORT_SYMBOL_GPL(ata_unpack_xfermask);
6939 EXPORT_SYMBOL_GPL(ata_xfer_mask2mode);
6940 EXPORT_SYMBOL_GPL(ata_xfer_mode2mask);
6941 EXPORT_SYMBOL_GPL(ata_xfer_mode2shift);
6942 EXPORT_SYMBOL_GPL(ata_mode_string);
6943 EXPORT_SYMBOL_GPL(ata_id_xfermask);
6944 EXPORT_SYMBOL_GPL(ata_do_set_mode);
6945 EXPORT_SYMBOL_GPL(ata_std_qc_defer);
6946 EXPORT_SYMBOL_GPL(ata_noop_qc_prep);
6947 EXPORT_SYMBOL_GPL(ata_dev_disable);
6948 EXPORT_SYMBOL_GPL(sata_set_spd);
6949 EXPORT_SYMBOL_GPL(ata_wait_after_reset);
6950 EXPORT_SYMBOL_GPL(sata_link_debounce);
6951 EXPORT_SYMBOL_GPL(sata_link_resume);
6952 EXPORT_SYMBOL_GPL(sata_link_scr_lpm);
6953 EXPORT_SYMBOL_GPL(ata_std_prereset);
6954 EXPORT_SYMBOL_GPL(sata_link_hardreset);
6955 EXPORT_SYMBOL_GPL(sata_std_hardreset);
6956 EXPORT_SYMBOL_GPL(ata_std_postreset);
6957 EXPORT_SYMBOL_GPL(ata_dev_classify);
6958 EXPORT_SYMBOL_GPL(ata_dev_pair);
6959 EXPORT_SYMBOL_GPL(ata_ratelimit);
6960 EXPORT_SYMBOL_GPL(ata_msleep);
6961 EXPORT_SYMBOL_GPL(ata_wait_register);
6962 EXPORT_SYMBOL_GPL(ata_scsi_queuecmd);
6963 EXPORT_SYMBOL_GPL(ata_scsi_slave_config);
6964 EXPORT_SYMBOL_GPL(ata_scsi_slave_destroy);
6965 EXPORT_SYMBOL_GPL(ata_scsi_change_queue_depth);
6966 EXPORT_SYMBOL_GPL(__ata_change_queue_depth);
6967 EXPORT_SYMBOL_GPL(sata_scr_valid);
6968 EXPORT_SYMBOL_GPL(sata_scr_read);
6969 EXPORT_SYMBOL_GPL(sata_scr_write);
6970 EXPORT_SYMBOL_GPL(sata_scr_write_flush);
6971 EXPORT_SYMBOL_GPL(ata_link_online);
6972 EXPORT_SYMBOL_GPL(ata_link_offline);
6973 #ifdef CONFIG_PM
6974 EXPORT_SYMBOL_GPL(ata_host_suspend);
6975 EXPORT_SYMBOL_GPL(ata_host_resume);
6976 #endif /* CONFIG_PM */
6977 EXPORT_SYMBOL_GPL(ata_id_string);
6978 EXPORT_SYMBOL_GPL(ata_id_c_string);
6979 EXPORT_SYMBOL_GPL(ata_do_dev_read_id);
6980 EXPORT_SYMBOL_GPL(ata_scsi_simulate);
6981 
6982 EXPORT_SYMBOL_GPL(ata_pio_need_iordy);
6983 EXPORT_SYMBOL_GPL(ata_timing_find_mode);
6984 EXPORT_SYMBOL_GPL(ata_timing_compute);
6985 EXPORT_SYMBOL_GPL(ata_timing_merge);
6986 EXPORT_SYMBOL_GPL(ata_timing_cycle2mode);
6987 
6988 #ifdef CONFIG_PCI
6989 EXPORT_SYMBOL_GPL(pci_test_config_bits);
6990 EXPORT_SYMBOL_GPL(ata_pci_remove_one);
6991 #ifdef CONFIG_PM
6992 EXPORT_SYMBOL_GPL(ata_pci_device_do_suspend);
6993 EXPORT_SYMBOL_GPL(ata_pci_device_do_resume);
6994 EXPORT_SYMBOL_GPL(ata_pci_device_suspend);
6995 EXPORT_SYMBOL_GPL(ata_pci_device_resume);
6996 #endif /* CONFIG_PM */
6997 #endif /* CONFIG_PCI */
6998 
6999 EXPORT_SYMBOL_GPL(ata_platform_remove_one);
7000 
7001 EXPORT_SYMBOL_GPL(__ata_ehi_push_desc);
7002 EXPORT_SYMBOL_GPL(ata_ehi_push_desc);
7003 EXPORT_SYMBOL_GPL(ata_ehi_clear_desc);
7004 EXPORT_SYMBOL_GPL(ata_port_desc);
7005 #ifdef CONFIG_PCI
7006 EXPORT_SYMBOL_GPL(ata_port_pbar_desc);
7007 #endif /* CONFIG_PCI */
7008 EXPORT_SYMBOL_GPL(ata_port_schedule_eh);
7009 EXPORT_SYMBOL_GPL(ata_link_abort);
7010 EXPORT_SYMBOL_GPL(ata_port_abort);
7011 EXPORT_SYMBOL_GPL(ata_port_freeze);
7012 EXPORT_SYMBOL_GPL(sata_async_notification);
7013 EXPORT_SYMBOL_GPL(ata_eh_freeze_port);
7014 EXPORT_SYMBOL_GPL(ata_eh_thaw_port);
7015 EXPORT_SYMBOL_GPL(ata_eh_qc_complete);
7016 EXPORT_SYMBOL_GPL(ata_eh_qc_retry);
7017 EXPORT_SYMBOL_GPL(ata_eh_analyze_ncq_error);
7018 EXPORT_SYMBOL_GPL(ata_do_eh);
7019 EXPORT_SYMBOL_GPL(ata_std_error_handler);
7020 
7021 EXPORT_SYMBOL_GPL(ata_cable_40wire);
7022 EXPORT_SYMBOL_GPL(ata_cable_80wire);
7023 EXPORT_SYMBOL_GPL(ata_cable_unknown);
7024 EXPORT_SYMBOL_GPL(ata_cable_ignore);
7025 EXPORT_SYMBOL_GPL(ata_cable_sata);
7026