xref: /linux/drivers/ata/libata-core.c (revision 071bf69a0220253a44acb8b2a27f7a262b9a46bf)
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/time.h>
54 #include <linux/interrupt.h>
55 #include <linux/completion.h>
56 #include <linux/suspend.h>
57 #include <linux/workqueue.h>
58 #include <linux/scatterlist.h>
59 #include <linux/io.h>
60 #include <linux/async.h>
61 #include <linux/log2.h>
62 #include <linux/slab.h>
63 #include <linux/glob.h>
64 #include <scsi/scsi.h>
65 #include <scsi/scsi_cmnd.h>
66 #include <scsi/scsi_host.h>
67 #include <linux/libata.h>
68 #include <asm/byteorder.h>
69 #include <asm/unaligned.h>
70 #include <linux/cdrom.h>
71 #include <linux/ratelimit.h>
72 #include <linux/leds.h>
73 #include <linux/pm_runtime.h>
74 #include <linux/platform_device.h>
75 
76 #define CREATE_TRACE_POINTS
77 #include <trace/events/libata.h>
78 
79 #include "libata.h"
80 #include "libata-transport.h"
81 
82 /* debounce timing parameters in msecs { interval, duration, timeout } */
83 const unsigned long sata_deb_timing_normal[]		= {   5,  100, 2000 };
84 const unsigned long sata_deb_timing_hotplug[]		= {  25,  500, 2000 };
85 const unsigned long sata_deb_timing_long[]		= { 100, 2000, 5000 };
86 
87 const struct ata_port_operations ata_base_port_ops = {
88 	.prereset		= ata_std_prereset,
89 	.postreset		= ata_std_postreset,
90 	.error_handler		= ata_std_error_handler,
91 	.sched_eh		= ata_std_sched_eh,
92 	.end_eh			= ata_std_end_eh,
93 };
94 
95 const struct ata_port_operations sata_port_ops = {
96 	.inherits		= &ata_base_port_ops,
97 
98 	.qc_defer		= ata_std_qc_defer,
99 	.hardreset		= sata_std_hardreset,
100 };
101 
102 static unsigned int ata_dev_init_params(struct ata_device *dev,
103 					u16 heads, u16 sectors);
104 static unsigned int ata_dev_set_xfermode(struct ata_device *dev);
105 static void ata_dev_xfermask(struct ata_device *dev);
106 static unsigned long ata_dev_blacklisted(const struct ata_device *dev);
107 
108 atomic_t ata_print_id = ATOMIC_INIT(0);
109 
110 struct ata_force_param {
111 	const char	*name;
112 	unsigned int	cbl;
113 	int		spd_limit;
114 	unsigned long	xfer_mask;
115 	unsigned int	horkage_on;
116 	unsigned int	horkage_off;
117 	unsigned int	lflags;
118 };
119 
120 struct ata_force_ent {
121 	int			port;
122 	int			device;
123 	struct ata_force_param	param;
124 };
125 
126 static struct ata_force_ent *ata_force_tbl;
127 static int ata_force_tbl_size;
128 
129 static char ata_force_param_buf[PAGE_SIZE] __initdata;
130 /* param_buf is thrown away after initialization, disallow read */
131 module_param_string(force, ata_force_param_buf, sizeof(ata_force_param_buf), 0);
132 MODULE_PARM_DESC(force, "Force ATA configurations including cable type, link speed and transfer mode (see Documentation/kernel-parameters.txt for details)");
133 
134 static int atapi_enabled = 1;
135 module_param(atapi_enabled, int, 0444);
136 MODULE_PARM_DESC(atapi_enabled, "Enable discovery of ATAPI devices (0=off, 1=on [default])");
137 
138 static int atapi_dmadir = 0;
139 module_param(atapi_dmadir, int, 0444);
140 MODULE_PARM_DESC(atapi_dmadir, "Enable ATAPI DMADIR bridge support (0=off [default], 1=on)");
141 
142 int atapi_passthru16 = 1;
143 module_param(atapi_passthru16, int, 0444);
144 MODULE_PARM_DESC(atapi_passthru16, "Enable ATA_16 passthru for ATAPI devices (0=off, 1=on [default])");
145 
146 int libata_fua = 0;
147 module_param_named(fua, libata_fua, int, 0444);
148 MODULE_PARM_DESC(fua, "FUA support (0=off [default], 1=on)");
149 
150 static int ata_ignore_hpa;
151 module_param_named(ignore_hpa, ata_ignore_hpa, int, 0644);
152 MODULE_PARM_DESC(ignore_hpa, "Ignore HPA limit (0=keep BIOS limits, 1=ignore limits, using full disk)");
153 
154 static int libata_dma_mask = ATA_DMA_MASK_ATA|ATA_DMA_MASK_ATAPI|ATA_DMA_MASK_CFA;
155 module_param_named(dma, libata_dma_mask, int, 0444);
156 MODULE_PARM_DESC(dma, "DMA enable/disable (0x1==ATA, 0x2==ATAPI, 0x4==CF)");
157 
158 static int ata_probe_timeout;
159 module_param(ata_probe_timeout, int, 0444);
160 MODULE_PARM_DESC(ata_probe_timeout, "Set ATA probing timeout (seconds)");
161 
162 int libata_noacpi = 0;
163 module_param_named(noacpi, libata_noacpi, int, 0444);
164 MODULE_PARM_DESC(noacpi, "Disable the use of ACPI in probe/suspend/resume (0=off [default], 1=on)");
165 
166 int libata_allow_tpm = 0;
167 module_param_named(allow_tpm, libata_allow_tpm, int, 0444);
168 MODULE_PARM_DESC(allow_tpm, "Permit the use of TPM commands (0=off [default], 1=on)");
169 
170 static int atapi_an;
171 module_param(atapi_an, int, 0444);
172 MODULE_PARM_DESC(atapi_an, "Enable ATAPI AN media presence notification (0=0ff [default], 1=on)");
173 
174 MODULE_AUTHOR("Jeff Garzik");
175 MODULE_DESCRIPTION("Library module for ATA devices");
176 MODULE_LICENSE("GPL");
177 MODULE_VERSION(DRV_VERSION);
178 
179 
180 static bool ata_sstatus_online(u32 sstatus)
181 {
182 	return (sstatus & 0xf) == 0x3;
183 }
184 
185 /**
186  *	ata_link_next - link iteration helper
187  *	@link: the previous link, NULL to start
188  *	@ap: ATA port containing links to iterate
189  *	@mode: iteration mode, one of ATA_LITER_*
190  *
191  *	LOCKING:
192  *	Host lock or EH context.
193  *
194  *	RETURNS:
195  *	Pointer to the next link.
196  */
197 struct ata_link *ata_link_next(struct ata_link *link, struct ata_port *ap,
198 			       enum ata_link_iter_mode mode)
199 {
200 	BUG_ON(mode != ATA_LITER_EDGE &&
201 	       mode != ATA_LITER_PMP_FIRST && mode != ATA_LITER_HOST_FIRST);
202 
203 	/* NULL link indicates start of iteration */
204 	if (!link)
205 		switch (mode) {
206 		case ATA_LITER_EDGE:
207 		case ATA_LITER_PMP_FIRST:
208 			if (sata_pmp_attached(ap))
209 				return ap->pmp_link;
210 			/* fall through */
211 		case ATA_LITER_HOST_FIRST:
212 			return &ap->link;
213 		}
214 
215 	/* we just iterated over the host link, what's next? */
216 	if (link == &ap->link)
217 		switch (mode) {
218 		case ATA_LITER_HOST_FIRST:
219 			if (sata_pmp_attached(ap))
220 				return ap->pmp_link;
221 			/* fall through */
222 		case ATA_LITER_PMP_FIRST:
223 			if (unlikely(ap->slave_link))
224 				return ap->slave_link;
225 			/* fall through */
226 		case ATA_LITER_EDGE:
227 			return NULL;
228 		}
229 
230 	/* slave_link excludes PMP */
231 	if (unlikely(link == ap->slave_link))
232 		return NULL;
233 
234 	/* we were over a PMP link */
235 	if (++link < ap->pmp_link + ap->nr_pmp_links)
236 		return link;
237 
238 	if (mode == ATA_LITER_PMP_FIRST)
239 		return &ap->link;
240 
241 	return NULL;
242 }
243 
244 /**
245  *	ata_dev_next - device iteration helper
246  *	@dev: the previous device, NULL to start
247  *	@link: ATA link containing devices to iterate
248  *	@mode: iteration mode, one of ATA_DITER_*
249  *
250  *	LOCKING:
251  *	Host lock or EH context.
252  *
253  *	RETURNS:
254  *	Pointer to the next device.
255  */
256 struct ata_device *ata_dev_next(struct ata_device *dev, struct ata_link *link,
257 				enum ata_dev_iter_mode mode)
258 {
259 	BUG_ON(mode != ATA_DITER_ENABLED && mode != ATA_DITER_ENABLED_REVERSE &&
260 	       mode != ATA_DITER_ALL && mode != ATA_DITER_ALL_REVERSE);
261 
262 	/* NULL dev indicates start of iteration */
263 	if (!dev)
264 		switch (mode) {
265 		case ATA_DITER_ENABLED:
266 		case ATA_DITER_ALL:
267 			dev = link->device;
268 			goto check;
269 		case ATA_DITER_ENABLED_REVERSE:
270 		case ATA_DITER_ALL_REVERSE:
271 			dev = link->device + ata_link_max_devices(link) - 1;
272 			goto check;
273 		}
274 
275  next:
276 	/* move to the next one */
277 	switch (mode) {
278 	case ATA_DITER_ENABLED:
279 	case ATA_DITER_ALL:
280 		if (++dev < link->device + ata_link_max_devices(link))
281 			goto check;
282 		return NULL;
283 	case ATA_DITER_ENABLED_REVERSE:
284 	case ATA_DITER_ALL_REVERSE:
285 		if (--dev >= link->device)
286 			goto check;
287 		return NULL;
288 	}
289 
290  check:
291 	if ((mode == ATA_DITER_ENABLED || mode == ATA_DITER_ENABLED_REVERSE) &&
292 	    !ata_dev_enabled(dev))
293 		goto next;
294 	return dev;
295 }
296 
297 /**
298  *	ata_dev_phys_link - find physical link for a device
299  *	@dev: ATA device to look up physical link for
300  *
301  *	Look up physical link which @dev is attached to.  Note that
302  *	this is different from @dev->link only when @dev is on slave
303  *	link.  For all other cases, it's the same as @dev->link.
304  *
305  *	LOCKING:
306  *	Don't care.
307  *
308  *	RETURNS:
309  *	Pointer to the found physical link.
310  */
311 struct ata_link *ata_dev_phys_link(struct ata_device *dev)
312 {
313 	struct ata_port *ap = dev->link->ap;
314 
315 	if (!ap->slave_link)
316 		return dev->link;
317 	if (!dev->devno)
318 		return &ap->link;
319 	return ap->slave_link;
320 }
321 
322 /**
323  *	ata_force_cbl - force cable type according to libata.force
324  *	@ap: ATA port of interest
325  *
326  *	Force cable type according to libata.force and whine about it.
327  *	The last entry which has matching port number is used, so it
328  *	can be specified as part of device force parameters.  For
329  *	example, both "a:40c,1.00:udma4" and "1.00:40c,udma4" have the
330  *	same effect.
331  *
332  *	LOCKING:
333  *	EH context.
334  */
335 void ata_force_cbl(struct ata_port *ap)
336 {
337 	int i;
338 
339 	for (i = ata_force_tbl_size - 1; i >= 0; i--) {
340 		const struct ata_force_ent *fe = &ata_force_tbl[i];
341 
342 		if (fe->port != -1 && fe->port != ap->print_id)
343 			continue;
344 
345 		if (fe->param.cbl == ATA_CBL_NONE)
346 			continue;
347 
348 		ap->cbl = fe->param.cbl;
349 		ata_port_notice(ap, "FORCE: cable set to %s\n", fe->param.name);
350 		return;
351 	}
352 }
353 
354 /**
355  *	ata_force_link_limits - force link limits according to libata.force
356  *	@link: ATA link of interest
357  *
358  *	Force link flags and SATA spd limit according to libata.force
359  *	and whine about it.  When only the port part is specified
360  *	(e.g. 1:), the limit applies to all links connected to both
361  *	the host link and all fan-out ports connected via PMP.  If the
362  *	device part is specified as 0 (e.g. 1.00:), it specifies the
363  *	first fan-out link not the host link.  Device number 15 always
364  *	points to the host link whether PMP is attached or not.  If the
365  *	controller has slave link, device number 16 points to it.
366  *
367  *	LOCKING:
368  *	EH context.
369  */
370 static void ata_force_link_limits(struct ata_link *link)
371 {
372 	bool did_spd = false;
373 	int linkno = link->pmp;
374 	int i;
375 
376 	if (ata_is_host_link(link))
377 		linkno += 15;
378 
379 	for (i = ata_force_tbl_size - 1; i >= 0; i--) {
380 		const struct ata_force_ent *fe = &ata_force_tbl[i];
381 
382 		if (fe->port != -1 && fe->port != link->ap->print_id)
383 			continue;
384 
385 		if (fe->device != -1 && fe->device != linkno)
386 			continue;
387 
388 		/* only honor the first spd limit */
389 		if (!did_spd && fe->param.spd_limit) {
390 			link->hw_sata_spd_limit = (1 << fe->param.spd_limit) - 1;
391 			ata_link_notice(link, "FORCE: PHY spd limit set to %s\n",
392 					fe->param.name);
393 			did_spd = true;
394 		}
395 
396 		/* let lflags stack */
397 		if (fe->param.lflags) {
398 			link->flags |= fe->param.lflags;
399 			ata_link_notice(link,
400 					"FORCE: link flag 0x%x forced -> 0x%x\n",
401 					fe->param.lflags, link->flags);
402 		}
403 	}
404 }
405 
406 /**
407  *	ata_force_xfermask - force xfermask according to libata.force
408  *	@dev: ATA device of interest
409  *
410  *	Force xfer_mask according to libata.force and whine about it.
411  *	For consistency with link selection, device number 15 selects
412  *	the first device connected to the host link.
413  *
414  *	LOCKING:
415  *	EH context.
416  */
417 static void ata_force_xfermask(struct ata_device *dev)
418 {
419 	int devno = dev->link->pmp + dev->devno;
420 	int alt_devno = devno;
421 	int i;
422 
423 	/* allow n.15/16 for devices attached to host port */
424 	if (ata_is_host_link(dev->link))
425 		alt_devno += 15;
426 
427 	for (i = ata_force_tbl_size - 1; i >= 0; i--) {
428 		const struct ata_force_ent *fe = &ata_force_tbl[i];
429 		unsigned long pio_mask, mwdma_mask, udma_mask;
430 
431 		if (fe->port != -1 && fe->port != dev->link->ap->print_id)
432 			continue;
433 
434 		if (fe->device != -1 && fe->device != devno &&
435 		    fe->device != alt_devno)
436 			continue;
437 
438 		if (!fe->param.xfer_mask)
439 			continue;
440 
441 		ata_unpack_xfermask(fe->param.xfer_mask,
442 				    &pio_mask, &mwdma_mask, &udma_mask);
443 		if (udma_mask)
444 			dev->udma_mask = udma_mask;
445 		else if (mwdma_mask) {
446 			dev->udma_mask = 0;
447 			dev->mwdma_mask = mwdma_mask;
448 		} else {
449 			dev->udma_mask = 0;
450 			dev->mwdma_mask = 0;
451 			dev->pio_mask = pio_mask;
452 		}
453 
454 		ata_dev_notice(dev, "FORCE: xfer_mask set to %s\n",
455 			       fe->param.name);
456 		return;
457 	}
458 }
459 
460 /**
461  *	ata_force_horkage - force horkage according to libata.force
462  *	@dev: ATA device of interest
463  *
464  *	Force horkage according to libata.force and whine about it.
465  *	For consistency with link selection, device number 15 selects
466  *	the first device connected to the host link.
467  *
468  *	LOCKING:
469  *	EH context.
470  */
471 static void ata_force_horkage(struct ata_device *dev)
472 {
473 	int devno = dev->link->pmp + dev->devno;
474 	int alt_devno = devno;
475 	int i;
476 
477 	/* allow n.15/16 for devices attached to host port */
478 	if (ata_is_host_link(dev->link))
479 		alt_devno += 15;
480 
481 	for (i = 0; i < ata_force_tbl_size; i++) {
482 		const struct ata_force_ent *fe = &ata_force_tbl[i];
483 
484 		if (fe->port != -1 && fe->port != dev->link->ap->print_id)
485 			continue;
486 
487 		if (fe->device != -1 && fe->device != devno &&
488 		    fe->device != alt_devno)
489 			continue;
490 
491 		if (!(~dev->horkage & fe->param.horkage_on) &&
492 		    !(dev->horkage & fe->param.horkage_off))
493 			continue;
494 
495 		dev->horkage |= fe->param.horkage_on;
496 		dev->horkage &= ~fe->param.horkage_off;
497 
498 		ata_dev_notice(dev, "FORCE: horkage modified (%s)\n",
499 			       fe->param.name);
500 	}
501 }
502 
503 /**
504  *	atapi_cmd_type - Determine ATAPI command type from SCSI opcode
505  *	@opcode: SCSI opcode
506  *
507  *	Determine ATAPI command type from @opcode.
508  *
509  *	LOCKING:
510  *	None.
511  *
512  *	RETURNS:
513  *	ATAPI_{READ|WRITE|READ_CD|PASS_THRU|MISC}
514  */
515 int atapi_cmd_type(u8 opcode)
516 {
517 	switch (opcode) {
518 	case GPCMD_READ_10:
519 	case GPCMD_READ_12:
520 		return ATAPI_READ;
521 
522 	case GPCMD_WRITE_10:
523 	case GPCMD_WRITE_12:
524 	case GPCMD_WRITE_AND_VERIFY_10:
525 		return ATAPI_WRITE;
526 
527 	case GPCMD_READ_CD:
528 	case GPCMD_READ_CD_MSF:
529 		return ATAPI_READ_CD;
530 
531 	case ATA_16:
532 	case ATA_12:
533 		if (atapi_passthru16)
534 			return ATAPI_PASS_THRU;
535 		/* fall thru */
536 	default:
537 		return ATAPI_MISC;
538 	}
539 }
540 
541 /**
542  *	ata_tf_to_fis - Convert ATA taskfile to SATA FIS structure
543  *	@tf: Taskfile to convert
544  *	@pmp: Port multiplier port
545  *	@is_cmd: This FIS is for command
546  *	@fis: Buffer into which data will output
547  *
548  *	Converts a standard ATA taskfile to a Serial ATA
549  *	FIS structure (Register - Host to Device).
550  *
551  *	LOCKING:
552  *	Inherited from caller.
553  */
554 void ata_tf_to_fis(const struct ata_taskfile *tf, u8 pmp, int is_cmd, u8 *fis)
555 {
556 	fis[0] = 0x27;			/* Register - Host to Device FIS */
557 	fis[1] = pmp & 0xf;		/* Port multiplier number*/
558 	if (is_cmd)
559 		fis[1] |= (1 << 7);	/* bit 7 indicates Command FIS */
560 
561 	fis[2] = tf->command;
562 	fis[3] = tf->feature;
563 
564 	fis[4] = tf->lbal;
565 	fis[5] = tf->lbam;
566 	fis[6] = tf->lbah;
567 	fis[7] = tf->device;
568 
569 	fis[8] = tf->hob_lbal;
570 	fis[9] = tf->hob_lbam;
571 	fis[10] = tf->hob_lbah;
572 	fis[11] = tf->hob_feature;
573 
574 	fis[12] = tf->nsect;
575 	fis[13] = tf->hob_nsect;
576 	fis[14] = 0;
577 	fis[15] = tf->ctl;
578 
579 	fis[16] = tf->auxiliary & 0xff;
580 	fis[17] = (tf->auxiliary >> 8) & 0xff;
581 	fis[18] = (tf->auxiliary >> 16) & 0xff;
582 	fis[19] = (tf->auxiliary >> 24) & 0xff;
583 }
584 
585 /**
586  *	ata_tf_from_fis - Convert SATA FIS to ATA taskfile
587  *	@fis: Buffer from which data will be input
588  *	@tf: Taskfile to output
589  *
590  *	Converts a serial ATA FIS structure to a standard ATA taskfile.
591  *
592  *	LOCKING:
593  *	Inherited from caller.
594  */
595 
596 void ata_tf_from_fis(const u8 *fis, struct ata_taskfile *tf)
597 {
598 	tf->command	= fis[2];	/* status */
599 	tf->feature	= fis[3];	/* error */
600 
601 	tf->lbal	= fis[4];
602 	tf->lbam	= fis[5];
603 	tf->lbah	= fis[6];
604 	tf->device	= fis[7];
605 
606 	tf->hob_lbal	= fis[8];
607 	tf->hob_lbam	= fis[9];
608 	tf->hob_lbah	= fis[10];
609 
610 	tf->nsect	= fis[12];
611 	tf->hob_nsect	= fis[13];
612 }
613 
614 static const u8 ata_rw_cmds[] = {
615 	/* pio multi */
616 	ATA_CMD_READ_MULTI,
617 	ATA_CMD_WRITE_MULTI,
618 	ATA_CMD_READ_MULTI_EXT,
619 	ATA_CMD_WRITE_MULTI_EXT,
620 	0,
621 	0,
622 	0,
623 	ATA_CMD_WRITE_MULTI_FUA_EXT,
624 	/* pio */
625 	ATA_CMD_PIO_READ,
626 	ATA_CMD_PIO_WRITE,
627 	ATA_CMD_PIO_READ_EXT,
628 	ATA_CMD_PIO_WRITE_EXT,
629 	0,
630 	0,
631 	0,
632 	0,
633 	/* dma */
634 	ATA_CMD_READ,
635 	ATA_CMD_WRITE,
636 	ATA_CMD_READ_EXT,
637 	ATA_CMD_WRITE_EXT,
638 	0,
639 	0,
640 	0,
641 	ATA_CMD_WRITE_FUA_EXT
642 };
643 
644 /**
645  *	ata_rwcmd_protocol - set taskfile r/w commands and protocol
646  *	@tf: command to examine and configure
647  *	@dev: device tf belongs to
648  *
649  *	Examine the device configuration and tf->flags to calculate
650  *	the proper read/write commands and protocol to use.
651  *
652  *	LOCKING:
653  *	caller.
654  */
655 static int ata_rwcmd_protocol(struct ata_taskfile *tf, struct ata_device *dev)
656 {
657 	u8 cmd;
658 
659 	int index, fua, lba48, write;
660 
661 	fua = (tf->flags & ATA_TFLAG_FUA) ? 4 : 0;
662 	lba48 = (tf->flags & ATA_TFLAG_LBA48) ? 2 : 0;
663 	write = (tf->flags & ATA_TFLAG_WRITE) ? 1 : 0;
664 
665 	if (dev->flags & ATA_DFLAG_PIO) {
666 		tf->protocol = ATA_PROT_PIO;
667 		index = dev->multi_count ? 0 : 8;
668 	} else if (lba48 && (dev->link->ap->flags & ATA_FLAG_PIO_LBA48)) {
669 		/* Unable to use DMA due to host limitation */
670 		tf->protocol = ATA_PROT_PIO;
671 		index = dev->multi_count ? 0 : 8;
672 	} else {
673 		tf->protocol = ATA_PROT_DMA;
674 		index = 16;
675 	}
676 
677 	cmd = ata_rw_cmds[index + fua + lba48 + write];
678 	if (cmd) {
679 		tf->command = cmd;
680 		return 0;
681 	}
682 	return -1;
683 }
684 
685 /**
686  *	ata_tf_read_block - Read block address from ATA taskfile
687  *	@tf: ATA taskfile of interest
688  *	@dev: ATA device @tf belongs to
689  *
690  *	LOCKING:
691  *	None.
692  *
693  *	Read block address from @tf.  This function can handle all
694  *	three address formats - LBA, LBA48 and CHS.  tf->protocol and
695  *	flags select the address format to use.
696  *
697  *	RETURNS:
698  *	Block address read from @tf.
699  */
700 u64 ata_tf_read_block(const struct ata_taskfile *tf, struct ata_device *dev)
701 {
702 	u64 block = 0;
703 
704 	if (tf->flags & ATA_TFLAG_LBA) {
705 		if (tf->flags & ATA_TFLAG_LBA48) {
706 			block |= (u64)tf->hob_lbah << 40;
707 			block |= (u64)tf->hob_lbam << 32;
708 			block |= (u64)tf->hob_lbal << 24;
709 		} else
710 			block |= (tf->device & 0xf) << 24;
711 
712 		block |= tf->lbah << 16;
713 		block |= tf->lbam << 8;
714 		block |= tf->lbal;
715 	} else {
716 		u32 cyl, head, sect;
717 
718 		cyl = tf->lbam | (tf->lbah << 8);
719 		head = tf->device & 0xf;
720 		sect = tf->lbal;
721 
722 		if (!sect) {
723 			ata_dev_warn(dev,
724 				     "device reported invalid CHS sector 0\n");
725 			return U64_MAX;
726 		}
727 
728 		block = (cyl * dev->heads + head) * dev->sectors + sect - 1;
729 	}
730 
731 	return block;
732 }
733 
734 /**
735  *	ata_build_rw_tf - Build ATA taskfile for given read/write request
736  *	@tf: Target ATA taskfile
737  *	@dev: ATA device @tf belongs to
738  *	@block: Block address
739  *	@n_block: Number of blocks
740  *	@tf_flags: RW/FUA etc...
741  *	@tag: tag
742  *
743  *	LOCKING:
744  *	None.
745  *
746  *	Build ATA taskfile @tf for read/write request described by
747  *	@block, @n_block, @tf_flags and @tag on @dev.
748  *
749  *	RETURNS:
750  *
751  *	0 on success, -ERANGE if the request is too large for @dev,
752  *	-EINVAL if the request is invalid.
753  */
754 int ata_build_rw_tf(struct ata_taskfile *tf, struct ata_device *dev,
755 		    u64 block, u32 n_block, unsigned int tf_flags,
756 		    unsigned int tag)
757 {
758 	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
759 	tf->flags |= tf_flags;
760 
761 	if (ata_ncq_enabled(dev) && likely(tag != ATA_TAG_INTERNAL)) {
762 		/* yay, NCQ */
763 		if (!lba_48_ok(block, n_block))
764 			return -ERANGE;
765 
766 		tf->protocol = ATA_PROT_NCQ;
767 		tf->flags |= ATA_TFLAG_LBA | ATA_TFLAG_LBA48;
768 
769 		if (tf->flags & ATA_TFLAG_WRITE)
770 			tf->command = ATA_CMD_FPDMA_WRITE;
771 		else
772 			tf->command = ATA_CMD_FPDMA_READ;
773 
774 		tf->nsect = tag << 3;
775 		tf->hob_feature = (n_block >> 8) & 0xff;
776 		tf->feature = n_block & 0xff;
777 
778 		tf->hob_lbah = (block >> 40) & 0xff;
779 		tf->hob_lbam = (block >> 32) & 0xff;
780 		tf->hob_lbal = (block >> 24) & 0xff;
781 		tf->lbah = (block >> 16) & 0xff;
782 		tf->lbam = (block >> 8) & 0xff;
783 		tf->lbal = block & 0xff;
784 
785 		tf->device = ATA_LBA;
786 		if (tf->flags & ATA_TFLAG_FUA)
787 			tf->device |= 1 << 7;
788 	} else if (dev->flags & ATA_DFLAG_LBA) {
789 		tf->flags |= ATA_TFLAG_LBA;
790 
791 		if (lba_28_ok(block, n_block)) {
792 			/* use LBA28 */
793 			tf->device |= (block >> 24) & 0xf;
794 		} else if (lba_48_ok(block, n_block)) {
795 			if (!(dev->flags & ATA_DFLAG_LBA48))
796 				return -ERANGE;
797 
798 			/* use LBA48 */
799 			tf->flags |= ATA_TFLAG_LBA48;
800 
801 			tf->hob_nsect = (n_block >> 8) & 0xff;
802 
803 			tf->hob_lbah = (block >> 40) & 0xff;
804 			tf->hob_lbam = (block >> 32) & 0xff;
805 			tf->hob_lbal = (block >> 24) & 0xff;
806 		} else
807 			/* request too large even for LBA48 */
808 			return -ERANGE;
809 
810 		if (unlikely(ata_rwcmd_protocol(tf, dev) < 0))
811 			return -EINVAL;
812 
813 		tf->nsect = n_block & 0xff;
814 
815 		tf->lbah = (block >> 16) & 0xff;
816 		tf->lbam = (block >> 8) & 0xff;
817 		tf->lbal = block & 0xff;
818 
819 		tf->device |= ATA_LBA;
820 	} else {
821 		/* CHS */
822 		u32 sect, head, cyl, track;
823 
824 		/* The request -may- be too large for CHS addressing. */
825 		if (!lba_28_ok(block, n_block))
826 			return -ERANGE;
827 
828 		if (unlikely(ata_rwcmd_protocol(tf, dev) < 0))
829 			return -EINVAL;
830 
831 		/* Convert LBA to CHS */
832 		track = (u32)block / dev->sectors;
833 		cyl   = track / dev->heads;
834 		head  = track % dev->heads;
835 		sect  = (u32)block % dev->sectors + 1;
836 
837 		DPRINTK("block %u track %u cyl %u head %u sect %u\n",
838 			(u32)block, track, cyl, head, sect);
839 
840 		/* Check whether the converted CHS can fit.
841 		   Cylinder: 0-65535
842 		   Head: 0-15
843 		   Sector: 1-255*/
844 		if ((cyl >> 16) || (head >> 4) || (sect >> 8) || (!sect))
845 			return -ERANGE;
846 
847 		tf->nsect = n_block & 0xff; /* Sector count 0 means 256 sectors */
848 		tf->lbal = sect;
849 		tf->lbam = cyl;
850 		tf->lbah = cyl >> 8;
851 		tf->device |= head;
852 	}
853 
854 	return 0;
855 }
856 
857 /**
858  *	ata_pack_xfermask - Pack pio, mwdma and udma masks into xfer_mask
859  *	@pio_mask: pio_mask
860  *	@mwdma_mask: mwdma_mask
861  *	@udma_mask: udma_mask
862  *
863  *	Pack @pio_mask, @mwdma_mask and @udma_mask into a single
864  *	unsigned int xfer_mask.
865  *
866  *	LOCKING:
867  *	None.
868  *
869  *	RETURNS:
870  *	Packed xfer_mask.
871  */
872 unsigned long ata_pack_xfermask(unsigned long pio_mask,
873 				unsigned long mwdma_mask,
874 				unsigned long udma_mask)
875 {
876 	return ((pio_mask << ATA_SHIFT_PIO) & ATA_MASK_PIO) |
877 		((mwdma_mask << ATA_SHIFT_MWDMA) & ATA_MASK_MWDMA) |
878 		((udma_mask << ATA_SHIFT_UDMA) & ATA_MASK_UDMA);
879 }
880 
881 /**
882  *	ata_unpack_xfermask - Unpack xfer_mask into pio, mwdma and udma masks
883  *	@xfer_mask: xfer_mask to unpack
884  *	@pio_mask: resulting pio_mask
885  *	@mwdma_mask: resulting mwdma_mask
886  *	@udma_mask: resulting udma_mask
887  *
888  *	Unpack @xfer_mask into @pio_mask, @mwdma_mask and @udma_mask.
889  *	Any NULL destination masks will be ignored.
890  */
891 void ata_unpack_xfermask(unsigned long xfer_mask, unsigned long *pio_mask,
892 			 unsigned long *mwdma_mask, unsigned long *udma_mask)
893 {
894 	if (pio_mask)
895 		*pio_mask = (xfer_mask & ATA_MASK_PIO) >> ATA_SHIFT_PIO;
896 	if (mwdma_mask)
897 		*mwdma_mask = (xfer_mask & ATA_MASK_MWDMA) >> ATA_SHIFT_MWDMA;
898 	if (udma_mask)
899 		*udma_mask = (xfer_mask & ATA_MASK_UDMA) >> ATA_SHIFT_UDMA;
900 }
901 
902 static const struct ata_xfer_ent {
903 	int shift, bits;
904 	u8 base;
905 } ata_xfer_tbl[] = {
906 	{ ATA_SHIFT_PIO, ATA_NR_PIO_MODES, XFER_PIO_0 },
907 	{ ATA_SHIFT_MWDMA, ATA_NR_MWDMA_MODES, XFER_MW_DMA_0 },
908 	{ ATA_SHIFT_UDMA, ATA_NR_UDMA_MODES, XFER_UDMA_0 },
909 	{ -1, },
910 };
911 
912 /**
913  *	ata_xfer_mask2mode - Find matching XFER_* for the given xfer_mask
914  *	@xfer_mask: xfer_mask of interest
915  *
916  *	Return matching XFER_* value for @xfer_mask.  Only the highest
917  *	bit of @xfer_mask is considered.
918  *
919  *	LOCKING:
920  *	None.
921  *
922  *	RETURNS:
923  *	Matching XFER_* value, 0xff if no match found.
924  */
925 u8 ata_xfer_mask2mode(unsigned long xfer_mask)
926 {
927 	int highbit = fls(xfer_mask) - 1;
928 	const struct ata_xfer_ent *ent;
929 
930 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
931 		if (highbit >= ent->shift && highbit < ent->shift + ent->bits)
932 			return ent->base + highbit - ent->shift;
933 	return 0xff;
934 }
935 
936 /**
937  *	ata_xfer_mode2mask - Find matching xfer_mask for XFER_*
938  *	@xfer_mode: XFER_* of interest
939  *
940  *	Return matching xfer_mask for @xfer_mode.
941  *
942  *	LOCKING:
943  *	None.
944  *
945  *	RETURNS:
946  *	Matching xfer_mask, 0 if no match found.
947  */
948 unsigned long ata_xfer_mode2mask(u8 xfer_mode)
949 {
950 	const struct ata_xfer_ent *ent;
951 
952 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
953 		if (xfer_mode >= ent->base && xfer_mode < ent->base + ent->bits)
954 			return ((2 << (ent->shift + xfer_mode - ent->base)) - 1)
955 				& ~((1 << ent->shift) - 1);
956 	return 0;
957 }
958 
959 /**
960  *	ata_xfer_mode2shift - Find matching xfer_shift for XFER_*
961  *	@xfer_mode: XFER_* of interest
962  *
963  *	Return matching xfer_shift for @xfer_mode.
964  *
965  *	LOCKING:
966  *	None.
967  *
968  *	RETURNS:
969  *	Matching xfer_shift, -1 if no match found.
970  */
971 int ata_xfer_mode2shift(unsigned long xfer_mode)
972 {
973 	const struct ata_xfer_ent *ent;
974 
975 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
976 		if (xfer_mode >= ent->base && xfer_mode < ent->base + ent->bits)
977 			return ent->shift;
978 	return -1;
979 }
980 
981 /**
982  *	ata_mode_string - convert xfer_mask to string
983  *	@xfer_mask: mask of bits supported; only highest bit counts.
984  *
985  *	Determine string which represents the highest speed
986  *	(highest bit in @modemask).
987  *
988  *	LOCKING:
989  *	None.
990  *
991  *	RETURNS:
992  *	Constant C string representing highest speed listed in
993  *	@mode_mask, or the constant C string "<n/a>".
994  */
995 const char *ata_mode_string(unsigned long xfer_mask)
996 {
997 	static const char * const xfer_mode_str[] = {
998 		"PIO0",
999 		"PIO1",
1000 		"PIO2",
1001 		"PIO3",
1002 		"PIO4",
1003 		"PIO5",
1004 		"PIO6",
1005 		"MWDMA0",
1006 		"MWDMA1",
1007 		"MWDMA2",
1008 		"MWDMA3",
1009 		"MWDMA4",
1010 		"UDMA/16",
1011 		"UDMA/25",
1012 		"UDMA/33",
1013 		"UDMA/44",
1014 		"UDMA/66",
1015 		"UDMA/100",
1016 		"UDMA/133",
1017 		"UDMA7",
1018 	};
1019 	int highbit;
1020 
1021 	highbit = fls(xfer_mask) - 1;
1022 	if (highbit >= 0 && highbit < ARRAY_SIZE(xfer_mode_str))
1023 		return xfer_mode_str[highbit];
1024 	return "<n/a>";
1025 }
1026 
1027 const char *sata_spd_string(unsigned int spd)
1028 {
1029 	static const char * const spd_str[] = {
1030 		"1.5 Gbps",
1031 		"3.0 Gbps",
1032 		"6.0 Gbps",
1033 	};
1034 
1035 	if (spd == 0 || (spd - 1) >= ARRAY_SIZE(spd_str))
1036 		return "<unknown>";
1037 	return spd_str[spd - 1];
1038 }
1039 
1040 /**
1041  *	ata_dev_classify - determine device type based on ATA-spec signature
1042  *	@tf: ATA taskfile register set for device to be identified
1043  *
1044  *	Determine from taskfile register contents whether a device is
1045  *	ATA or ATAPI, as per "Signature and persistence" section
1046  *	of ATA/PI spec (volume 1, sect 5.14).
1047  *
1048  *	LOCKING:
1049  *	None.
1050  *
1051  *	RETURNS:
1052  *	Device type, %ATA_DEV_ATA, %ATA_DEV_ATAPI, %ATA_DEV_PMP,
1053  *	%ATA_DEV_ZAC, or %ATA_DEV_UNKNOWN the event of failure.
1054  */
1055 unsigned int ata_dev_classify(const struct ata_taskfile *tf)
1056 {
1057 	/* Apple's open source Darwin code hints that some devices only
1058 	 * put a proper signature into the LBA mid/high registers,
1059 	 * So, we only check those.  It's sufficient for uniqueness.
1060 	 *
1061 	 * ATA/ATAPI-7 (d1532v1r1: Feb. 19, 2003) specified separate
1062 	 * signatures for ATA and ATAPI devices attached on SerialATA,
1063 	 * 0x3c/0xc3 and 0x69/0x96 respectively.  However, SerialATA
1064 	 * spec has never mentioned about using different signatures
1065 	 * for ATA/ATAPI devices.  Then, Serial ATA II: Port
1066 	 * Multiplier specification began to use 0x69/0x96 to identify
1067 	 * port multpliers and 0x3c/0xc3 to identify SEMB device.
1068 	 * ATA/ATAPI-7 dropped descriptions about 0x3c/0xc3 and
1069 	 * 0x69/0x96 shortly and described them as reserved for
1070 	 * SerialATA.
1071 	 *
1072 	 * We follow the current spec and consider that 0x69/0x96
1073 	 * identifies a port multiplier and 0x3c/0xc3 a SEMB device.
1074 	 * Unfortunately, WDC WD1600JS-62MHB5 (a hard drive) reports
1075 	 * SEMB signature.  This is worked around in
1076 	 * ata_dev_read_id().
1077 	 */
1078 	if ((tf->lbam == 0) && (tf->lbah == 0)) {
1079 		DPRINTK("found ATA device by sig\n");
1080 		return ATA_DEV_ATA;
1081 	}
1082 
1083 	if ((tf->lbam == 0x14) && (tf->lbah == 0xeb)) {
1084 		DPRINTK("found ATAPI device by sig\n");
1085 		return ATA_DEV_ATAPI;
1086 	}
1087 
1088 	if ((tf->lbam == 0x69) && (tf->lbah == 0x96)) {
1089 		DPRINTK("found PMP device by sig\n");
1090 		return ATA_DEV_PMP;
1091 	}
1092 
1093 	if ((tf->lbam == 0x3c) && (tf->lbah == 0xc3)) {
1094 		DPRINTK("found SEMB device by sig (could be ATA device)\n");
1095 		return ATA_DEV_SEMB;
1096 	}
1097 
1098 	if ((tf->lbam == 0xcd) && (tf->lbah == 0xab)) {
1099 		DPRINTK("found ZAC device by sig\n");
1100 		return ATA_DEV_ZAC;
1101 	}
1102 
1103 	DPRINTK("unknown device\n");
1104 	return ATA_DEV_UNKNOWN;
1105 }
1106 
1107 /**
1108  *	ata_id_string - Convert IDENTIFY DEVICE page into string
1109  *	@id: IDENTIFY DEVICE results we will examine
1110  *	@s: string into which data is output
1111  *	@ofs: offset into identify device page
1112  *	@len: length of string to return. must be an even number.
1113  *
1114  *	The strings in the IDENTIFY DEVICE page are broken up into
1115  *	16-bit chunks.  Run through the string, and output each
1116  *	8-bit chunk linearly, regardless of platform.
1117  *
1118  *	LOCKING:
1119  *	caller.
1120  */
1121 
1122 void ata_id_string(const u16 *id, unsigned char *s,
1123 		   unsigned int ofs, unsigned int len)
1124 {
1125 	unsigned int c;
1126 
1127 	BUG_ON(len & 1);
1128 
1129 	while (len > 0) {
1130 		c = id[ofs] >> 8;
1131 		*s = c;
1132 		s++;
1133 
1134 		c = id[ofs] & 0xff;
1135 		*s = c;
1136 		s++;
1137 
1138 		ofs++;
1139 		len -= 2;
1140 	}
1141 }
1142 
1143 /**
1144  *	ata_id_c_string - Convert IDENTIFY DEVICE page into C string
1145  *	@id: IDENTIFY DEVICE results we will examine
1146  *	@s: string into which data is output
1147  *	@ofs: offset into identify device page
1148  *	@len: length of string to return. must be an odd number.
1149  *
1150  *	This function is identical to ata_id_string except that it
1151  *	trims trailing spaces and terminates the resulting string with
1152  *	null.  @len must be actual maximum length (even number) + 1.
1153  *
1154  *	LOCKING:
1155  *	caller.
1156  */
1157 void ata_id_c_string(const u16 *id, unsigned char *s,
1158 		     unsigned int ofs, unsigned int len)
1159 {
1160 	unsigned char *p;
1161 
1162 	ata_id_string(id, s, ofs, len - 1);
1163 
1164 	p = s + strnlen(s, len - 1);
1165 	while (p > s && p[-1] == ' ')
1166 		p--;
1167 	*p = '\0';
1168 }
1169 
1170 static u64 ata_id_n_sectors(const u16 *id)
1171 {
1172 	if (ata_id_has_lba(id)) {
1173 		if (ata_id_has_lba48(id))
1174 			return ata_id_u64(id, ATA_ID_LBA_CAPACITY_2);
1175 		else
1176 			return ata_id_u32(id, ATA_ID_LBA_CAPACITY);
1177 	} else {
1178 		if (ata_id_current_chs_valid(id))
1179 			return id[ATA_ID_CUR_CYLS] * id[ATA_ID_CUR_HEADS] *
1180 			       id[ATA_ID_CUR_SECTORS];
1181 		else
1182 			return id[ATA_ID_CYLS] * id[ATA_ID_HEADS] *
1183 			       id[ATA_ID_SECTORS];
1184 	}
1185 }
1186 
1187 u64 ata_tf_to_lba48(const struct ata_taskfile *tf)
1188 {
1189 	u64 sectors = 0;
1190 
1191 	sectors |= ((u64)(tf->hob_lbah & 0xff)) << 40;
1192 	sectors |= ((u64)(tf->hob_lbam & 0xff)) << 32;
1193 	sectors |= ((u64)(tf->hob_lbal & 0xff)) << 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 u64 ata_tf_to_lba(const struct ata_taskfile *tf)
1202 {
1203 	u64 sectors = 0;
1204 
1205 	sectors |= (tf->device & 0x0f) << 24;
1206 	sectors |= (tf->lbah & 0xff) << 16;
1207 	sectors |= (tf->lbam & 0xff) << 8;
1208 	sectors |= (tf->lbal & 0xff);
1209 
1210 	return sectors;
1211 }
1212 
1213 /**
1214  *	ata_read_native_max_address - Read native max address
1215  *	@dev: target device
1216  *	@max_sectors: out parameter for the result native max address
1217  *
1218  *	Perform an LBA48 or LBA28 native size query upon the device in
1219  *	question.
1220  *
1221  *	RETURNS:
1222  *	0 on success, -EACCES if command is aborted by the drive.
1223  *	-EIO on other errors.
1224  */
1225 static int ata_read_native_max_address(struct ata_device *dev, u64 *max_sectors)
1226 {
1227 	unsigned int err_mask;
1228 	struct ata_taskfile tf;
1229 	int lba48 = ata_id_has_lba48(dev->id);
1230 
1231 	ata_tf_init(dev, &tf);
1232 
1233 	/* always clear all address registers */
1234 	tf.flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
1235 
1236 	if (lba48) {
1237 		tf.command = ATA_CMD_READ_NATIVE_MAX_EXT;
1238 		tf.flags |= ATA_TFLAG_LBA48;
1239 	} else
1240 		tf.command = ATA_CMD_READ_NATIVE_MAX;
1241 
1242 	tf.protocol = ATA_PROT_NODATA;
1243 	tf.device |= ATA_LBA;
1244 
1245 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
1246 	if (err_mask) {
1247 		ata_dev_warn(dev,
1248 			     "failed to read native max address (err_mask=0x%x)\n",
1249 			     err_mask);
1250 		if (err_mask == AC_ERR_DEV && (tf.feature & ATA_ABORTED))
1251 			return -EACCES;
1252 		return -EIO;
1253 	}
1254 
1255 	if (lba48)
1256 		*max_sectors = ata_tf_to_lba48(&tf) + 1;
1257 	else
1258 		*max_sectors = ata_tf_to_lba(&tf) + 1;
1259 	if (dev->horkage & ATA_HORKAGE_HPA_SIZE)
1260 		(*max_sectors)--;
1261 	return 0;
1262 }
1263 
1264 /**
1265  *	ata_set_max_sectors - Set max sectors
1266  *	@dev: target device
1267  *	@new_sectors: new max sectors value to set for the device
1268  *
1269  *	Set max sectors of @dev to @new_sectors.
1270  *
1271  *	RETURNS:
1272  *	0 on success, -EACCES if command is aborted or denied (due to
1273  *	previous non-volatile SET_MAX) by the drive.  -EIO on other
1274  *	errors.
1275  */
1276 static int ata_set_max_sectors(struct ata_device *dev, u64 new_sectors)
1277 {
1278 	unsigned int err_mask;
1279 	struct ata_taskfile tf;
1280 	int lba48 = ata_id_has_lba48(dev->id);
1281 
1282 	new_sectors--;
1283 
1284 	ata_tf_init(dev, &tf);
1285 
1286 	tf.flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
1287 
1288 	if (lba48) {
1289 		tf.command = ATA_CMD_SET_MAX_EXT;
1290 		tf.flags |= ATA_TFLAG_LBA48;
1291 
1292 		tf.hob_lbal = (new_sectors >> 24) & 0xff;
1293 		tf.hob_lbam = (new_sectors >> 32) & 0xff;
1294 		tf.hob_lbah = (new_sectors >> 40) & 0xff;
1295 	} else {
1296 		tf.command = ATA_CMD_SET_MAX;
1297 
1298 		tf.device |= (new_sectors >> 24) & 0xf;
1299 	}
1300 
1301 	tf.protocol = ATA_PROT_NODATA;
1302 	tf.device |= ATA_LBA;
1303 
1304 	tf.lbal = (new_sectors >> 0) & 0xff;
1305 	tf.lbam = (new_sectors >> 8) & 0xff;
1306 	tf.lbah = (new_sectors >> 16) & 0xff;
1307 
1308 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
1309 	if (err_mask) {
1310 		ata_dev_warn(dev,
1311 			     "failed to set max address (err_mask=0x%x)\n",
1312 			     err_mask);
1313 		if (err_mask == AC_ERR_DEV &&
1314 		    (tf.feature & (ATA_ABORTED | ATA_IDNF)))
1315 			return -EACCES;
1316 		return -EIO;
1317 	}
1318 
1319 	return 0;
1320 }
1321 
1322 /**
1323  *	ata_hpa_resize		-	Resize a device with an HPA set
1324  *	@dev: Device to resize
1325  *
1326  *	Read the size of an LBA28 or LBA48 disk with HPA features and resize
1327  *	it if required to the full size of the media. The caller must check
1328  *	the drive has the HPA feature set enabled.
1329  *
1330  *	RETURNS:
1331  *	0 on success, -errno on failure.
1332  */
1333 static int ata_hpa_resize(struct ata_device *dev)
1334 {
1335 	struct ata_eh_context *ehc = &dev->link->eh_context;
1336 	int print_info = ehc->i.flags & ATA_EHI_PRINTINFO;
1337 	bool unlock_hpa = ata_ignore_hpa || dev->flags & ATA_DFLAG_UNLOCK_HPA;
1338 	u64 sectors = ata_id_n_sectors(dev->id);
1339 	u64 native_sectors;
1340 	int rc;
1341 
1342 	/* do we need to do it? */
1343 	if ((dev->class != ATA_DEV_ATA && dev->class != ATA_DEV_ZAC) ||
1344 	    !ata_id_has_lba(dev->id) || !ata_id_hpa_enabled(dev->id) ||
1345 	    (dev->horkage & ATA_HORKAGE_BROKEN_HPA))
1346 		return 0;
1347 
1348 	/* read native max address */
1349 	rc = ata_read_native_max_address(dev, &native_sectors);
1350 	if (rc) {
1351 		/* If device aborted the command or HPA isn't going to
1352 		 * be unlocked, skip HPA resizing.
1353 		 */
1354 		if (rc == -EACCES || !unlock_hpa) {
1355 			ata_dev_warn(dev,
1356 				     "HPA support seems broken, skipping HPA handling\n");
1357 			dev->horkage |= ATA_HORKAGE_BROKEN_HPA;
1358 
1359 			/* we can continue if device aborted the command */
1360 			if (rc == -EACCES)
1361 				rc = 0;
1362 		}
1363 
1364 		return rc;
1365 	}
1366 	dev->n_native_sectors = native_sectors;
1367 
1368 	/* nothing to do? */
1369 	if (native_sectors <= sectors || !unlock_hpa) {
1370 		if (!print_info || native_sectors == sectors)
1371 			return 0;
1372 
1373 		if (native_sectors > sectors)
1374 			ata_dev_info(dev,
1375 				"HPA detected: current %llu, native %llu\n",
1376 				(unsigned long long)sectors,
1377 				(unsigned long long)native_sectors);
1378 		else if (native_sectors < sectors)
1379 			ata_dev_warn(dev,
1380 				"native sectors (%llu) is smaller than sectors (%llu)\n",
1381 				(unsigned long long)native_sectors,
1382 				(unsigned long long)sectors);
1383 		return 0;
1384 	}
1385 
1386 	/* let's unlock HPA */
1387 	rc = ata_set_max_sectors(dev, native_sectors);
1388 	if (rc == -EACCES) {
1389 		/* if device aborted the command, skip HPA resizing */
1390 		ata_dev_warn(dev,
1391 			     "device aborted resize (%llu -> %llu), skipping HPA handling\n",
1392 			     (unsigned long long)sectors,
1393 			     (unsigned long long)native_sectors);
1394 		dev->horkage |= ATA_HORKAGE_BROKEN_HPA;
1395 		return 0;
1396 	} else if (rc)
1397 		return rc;
1398 
1399 	/* re-read IDENTIFY data */
1400 	rc = ata_dev_reread_id(dev, 0);
1401 	if (rc) {
1402 		ata_dev_err(dev,
1403 			    "failed to re-read IDENTIFY data after HPA resizing\n");
1404 		return rc;
1405 	}
1406 
1407 	if (print_info) {
1408 		u64 new_sectors = ata_id_n_sectors(dev->id);
1409 		ata_dev_info(dev,
1410 			"HPA unlocked: %llu -> %llu, native %llu\n",
1411 			(unsigned long long)sectors,
1412 			(unsigned long long)new_sectors,
1413 			(unsigned long long)native_sectors);
1414 	}
1415 
1416 	return 0;
1417 }
1418 
1419 /**
1420  *	ata_dump_id - IDENTIFY DEVICE info debugging output
1421  *	@id: IDENTIFY DEVICE page to dump
1422  *
1423  *	Dump selected 16-bit words from the given IDENTIFY DEVICE
1424  *	page.
1425  *
1426  *	LOCKING:
1427  *	caller.
1428  */
1429 
1430 static inline void ata_dump_id(const u16 *id)
1431 {
1432 	DPRINTK("49==0x%04x  "
1433 		"53==0x%04x  "
1434 		"63==0x%04x  "
1435 		"64==0x%04x  "
1436 		"75==0x%04x  \n",
1437 		id[49],
1438 		id[53],
1439 		id[63],
1440 		id[64],
1441 		id[75]);
1442 	DPRINTK("80==0x%04x  "
1443 		"81==0x%04x  "
1444 		"82==0x%04x  "
1445 		"83==0x%04x  "
1446 		"84==0x%04x  \n",
1447 		id[80],
1448 		id[81],
1449 		id[82],
1450 		id[83],
1451 		id[84]);
1452 	DPRINTK("88==0x%04x  "
1453 		"93==0x%04x\n",
1454 		id[88],
1455 		id[93]);
1456 }
1457 
1458 /**
1459  *	ata_id_xfermask - Compute xfermask from the given IDENTIFY data
1460  *	@id: IDENTIFY data to compute xfer mask from
1461  *
1462  *	Compute the xfermask for this device. This is not as trivial
1463  *	as it seems if we must consider early devices correctly.
1464  *
1465  *	FIXME: pre IDE drive timing (do we care ?).
1466  *
1467  *	LOCKING:
1468  *	None.
1469  *
1470  *	RETURNS:
1471  *	Computed xfermask
1472  */
1473 unsigned long ata_id_xfermask(const u16 *id)
1474 {
1475 	unsigned long pio_mask, mwdma_mask, udma_mask;
1476 
1477 	/* Usual case. Word 53 indicates word 64 is valid */
1478 	if (id[ATA_ID_FIELD_VALID] & (1 << 1)) {
1479 		pio_mask = id[ATA_ID_PIO_MODES] & 0x03;
1480 		pio_mask <<= 3;
1481 		pio_mask |= 0x7;
1482 	} else {
1483 		/* If word 64 isn't valid then Word 51 high byte holds
1484 		 * the PIO timing number for the maximum. Turn it into
1485 		 * a mask.
1486 		 */
1487 		u8 mode = (id[ATA_ID_OLD_PIO_MODES] >> 8) & 0xFF;
1488 		if (mode < 5)	/* Valid PIO range */
1489 			pio_mask = (2 << mode) - 1;
1490 		else
1491 			pio_mask = 1;
1492 
1493 		/* But wait.. there's more. Design your standards by
1494 		 * committee and you too can get a free iordy field to
1495 		 * process. However its the speeds not the modes that
1496 		 * are supported... Note drivers using the timing API
1497 		 * will get this right anyway
1498 		 */
1499 	}
1500 
1501 	mwdma_mask = id[ATA_ID_MWDMA_MODES] & 0x07;
1502 
1503 	if (ata_id_is_cfa(id)) {
1504 		/*
1505 		 *	Process compact flash extended modes
1506 		 */
1507 		int pio = (id[ATA_ID_CFA_MODES] >> 0) & 0x7;
1508 		int dma = (id[ATA_ID_CFA_MODES] >> 3) & 0x7;
1509 
1510 		if (pio)
1511 			pio_mask |= (1 << 5);
1512 		if (pio > 1)
1513 			pio_mask |= (1 << 6);
1514 		if (dma)
1515 			mwdma_mask |= (1 << 3);
1516 		if (dma > 1)
1517 			mwdma_mask |= (1 << 4);
1518 	}
1519 
1520 	udma_mask = 0;
1521 	if (id[ATA_ID_FIELD_VALID] & (1 << 2))
1522 		udma_mask = id[ATA_ID_UDMA_MODES] & 0xff;
1523 
1524 	return ata_pack_xfermask(pio_mask, mwdma_mask, udma_mask);
1525 }
1526 
1527 static void ata_qc_complete_internal(struct ata_queued_cmd *qc)
1528 {
1529 	struct completion *waiting = qc->private_data;
1530 
1531 	complete(waiting);
1532 }
1533 
1534 /**
1535  *	ata_exec_internal_sg - execute libata internal command
1536  *	@dev: Device to which the command is sent
1537  *	@tf: Taskfile registers for the command and the result
1538  *	@cdb: CDB for packet command
1539  *	@dma_dir: Data transfer direction of the command
1540  *	@sgl: sg list for the data buffer of the command
1541  *	@n_elem: Number of sg entries
1542  *	@timeout: Timeout in msecs (0 for default)
1543  *
1544  *	Executes libata internal command with timeout.  @tf contains
1545  *	command on entry and result on return.  Timeout and error
1546  *	conditions are reported via return value.  No recovery action
1547  *	is taken after a command times out.  It's caller's duty to
1548  *	clean up after timeout.
1549  *
1550  *	LOCKING:
1551  *	None.  Should be called with kernel context, might sleep.
1552  *
1553  *	RETURNS:
1554  *	Zero on success, AC_ERR_* mask on failure
1555  */
1556 unsigned ata_exec_internal_sg(struct ata_device *dev,
1557 			      struct ata_taskfile *tf, const u8 *cdb,
1558 			      int dma_dir, struct scatterlist *sgl,
1559 			      unsigned int n_elem, unsigned long timeout)
1560 {
1561 	struct ata_link *link = dev->link;
1562 	struct ata_port *ap = link->ap;
1563 	u8 command = tf->command;
1564 	int auto_timeout = 0;
1565 	struct ata_queued_cmd *qc;
1566 	unsigned int tag, preempted_tag;
1567 	u32 preempted_sactive, preempted_qc_active;
1568 	int preempted_nr_active_links;
1569 	DECLARE_COMPLETION_ONSTACK(wait);
1570 	unsigned long flags;
1571 	unsigned int err_mask;
1572 	int rc;
1573 
1574 	spin_lock_irqsave(ap->lock, flags);
1575 
1576 	/* no internal command while frozen */
1577 	if (ap->pflags & ATA_PFLAG_FROZEN) {
1578 		spin_unlock_irqrestore(ap->lock, flags);
1579 		return AC_ERR_SYSTEM;
1580 	}
1581 
1582 	/* initialize internal qc */
1583 
1584 	/* XXX: Tag 0 is used for drivers with legacy EH as some
1585 	 * drivers choke if any other tag is given.  This breaks
1586 	 * ata_tag_internal() test for those drivers.  Don't use new
1587 	 * EH stuff without converting to it.
1588 	 */
1589 	if (ap->ops->error_handler)
1590 		tag = ATA_TAG_INTERNAL;
1591 	else
1592 		tag = 0;
1593 
1594 	qc = __ata_qc_from_tag(ap, tag);
1595 
1596 	qc->tag = tag;
1597 	qc->scsicmd = NULL;
1598 	qc->ap = ap;
1599 	qc->dev = dev;
1600 	ata_qc_reinit(qc);
1601 
1602 	preempted_tag = link->active_tag;
1603 	preempted_sactive = link->sactive;
1604 	preempted_qc_active = ap->qc_active;
1605 	preempted_nr_active_links = ap->nr_active_links;
1606 	link->active_tag = ATA_TAG_POISON;
1607 	link->sactive = 0;
1608 	ap->qc_active = 0;
1609 	ap->nr_active_links = 0;
1610 
1611 	/* prepare & issue qc */
1612 	qc->tf = *tf;
1613 	if (cdb)
1614 		memcpy(qc->cdb, cdb, ATAPI_CDB_LEN);
1615 
1616 	/* some SATA bridges need us to indicate data xfer direction */
1617 	if (tf->protocol == ATAPI_PROT_DMA && (dev->flags & ATA_DFLAG_DMADIR) &&
1618 	    dma_dir == DMA_FROM_DEVICE)
1619 		qc->tf.feature |= ATAPI_DMADIR;
1620 
1621 	qc->flags |= ATA_QCFLAG_RESULT_TF;
1622 	qc->dma_dir = dma_dir;
1623 	if (dma_dir != DMA_NONE) {
1624 		unsigned int i, buflen = 0;
1625 		struct scatterlist *sg;
1626 
1627 		for_each_sg(sgl, sg, n_elem, i)
1628 			buflen += sg->length;
1629 
1630 		ata_sg_init(qc, sgl, n_elem);
1631 		qc->nbytes = buflen;
1632 	}
1633 
1634 	qc->private_data = &wait;
1635 	qc->complete_fn = ata_qc_complete_internal;
1636 
1637 	ata_qc_issue(qc);
1638 
1639 	spin_unlock_irqrestore(ap->lock, flags);
1640 
1641 	if (!timeout) {
1642 		if (ata_probe_timeout)
1643 			timeout = ata_probe_timeout * 1000;
1644 		else {
1645 			timeout = ata_internal_cmd_timeout(dev, command);
1646 			auto_timeout = 1;
1647 		}
1648 	}
1649 
1650 	if (ap->ops->error_handler)
1651 		ata_eh_release(ap);
1652 
1653 	rc = wait_for_completion_timeout(&wait, msecs_to_jiffies(timeout));
1654 
1655 	if (ap->ops->error_handler)
1656 		ata_eh_acquire(ap);
1657 
1658 	ata_sff_flush_pio_task(ap);
1659 
1660 	if (!rc) {
1661 		spin_lock_irqsave(ap->lock, flags);
1662 
1663 		/* We're racing with irq here.  If we lose, the
1664 		 * following test prevents us from completing the qc
1665 		 * twice.  If we win, the port is frozen and will be
1666 		 * cleaned up by ->post_internal_cmd().
1667 		 */
1668 		if (qc->flags & ATA_QCFLAG_ACTIVE) {
1669 			qc->err_mask |= AC_ERR_TIMEOUT;
1670 
1671 			if (ap->ops->error_handler)
1672 				ata_port_freeze(ap);
1673 			else
1674 				ata_qc_complete(qc);
1675 
1676 			if (ata_msg_warn(ap))
1677 				ata_dev_warn(dev, "qc timeout (cmd 0x%x)\n",
1678 					     command);
1679 		}
1680 
1681 		spin_unlock_irqrestore(ap->lock, flags);
1682 	}
1683 
1684 	/* do post_internal_cmd */
1685 	if (ap->ops->post_internal_cmd)
1686 		ap->ops->post_internal_cmd(qc);
1687 
1688 	/* perform minimal error analysis */
1689 	if (qc->flags & ATA_QCFLAG_FAILED) {
1690 		if (qc->result_tf.command & (ATA_ERR | ATA_DF))
1691 			qc->err_mask |= AC_ERR_DEV;
1692 
1693 		if (!qc->err_mask)
1694 			qc->err_mask |= AC_ERR_OTHER;
1695 
1696 		if (qc->err_mask & ~AC_ERR_OTHER)
1697 			qc->err_mask &= ~AC_ERR_OTHER;
1698 	}
1699 
1700 	/* finish up */
1701 	spin_lock_irqsave(ap->lock, flags);
1702 
1703 	*tf = qc->result_tf;
1704 	err_mask = qc->err_mask;
1705 
1706 	ata_qc_free(qc);
1707 	link->active_tag = preempted_tag;
1708 	link->sactive = preempted_sactive;
1709 	ap->qc_active = preempted_qc_active;
1710 	ap->nr_active_links = preempted_nr_active_links;
1711 
1712 	spin_unlock_irqrestore(ap->lock, flags);
1713 
1714 	if ((err_mask & AC_ERR_TIMEOUT) && auto_timeout)
1715 		ata_internal_cmd_timed_out(dev, command);
1716 
1717 	return err_mask;
1718 }
1719 
1720 /**
1721  *	ata_exec_internal - execute libata internal command
1722  *	@dev: Device to which the command is sent
1723  *	@tf: Taskfile registers for the command and the result
1724  *	@cdb: CDB for packet command
1725  *	@dma_dir: Data transfer direction of the command
1726  *	@buf: Data buffer of the command
1727  *	@buflen: Length of data buffer
1728  *	@timeout: Timeout in msecs (0 for default)
1729  *
1730  *	Wrapper around ata_exec_internal_sg() which takes simple
1731  *	buffer instead of sg list.
1732  *
1733  *	LOCKING:
1734  *	None.  Should be called with kernel context, might sleep.
1735  *
1736  *	RETURNS:
1737  *	Zero on success, AC_ERR_* mask on failure
1738  */
1739 unsigned ata_exec_internal(struct ata_device *dev,
1740 			   struct ata_taskfile *tf, const u8 *cdb,
1741 			   int dma_dir, void *buf, unsigned int buflen,
1742 			   unsigned long timeout)
1743 {
1744 	struct scatterlist *psg = NULL, sg;
1745 	unsigned int n_elem = 0;
1746 
1747 	if (dma_dir != DMA_NONE) {
1748 		WARN_ON(!buf);
1749 		sg_init_one(&sg, buf, buflen);
1750 		psg = &sg;
1751 		n_elem++;
1752 	}
1753 
1754 	return ata_exec_internal_sg(dev, tf, cdb, dma_dir, psg, n_elem,
1755 				    timeout);
1756 }
1757 
1758 /**
1759  *	ata_pio_need_iordy	-	check if iordy needed
1760  *	@adev: ATA device
1761  *
1762  *	Check if the current speed of the device requires IORDY. Used
1763  *	by various controllers for chip configuration.
1764  */
1765 unsigned int ata_pio_need_iordy(const struct ata_device *adev)
1766 {
1767 	/* Don't set IORDY if we're preparing for reset.  IORDY may
1768 	 * lead to controller lock up on certain controllers if the
1769 	 * port is not occupied.  See bko#11703 for details.
1770 	 */
1771 	if (adev->link->ap->pflags & ATA_PFLAG_RESETTING)
1772 		return 0;
1773 	/* Controller doesn't support IORDY.  Probably a pointless
1774 	 * check as the caller should know this.
1775 	 */
1776 	if (adev->link->ap->flags & ATA_FLAG_NO_IORDY)
1777 		return 0;
1778 	/* CF spec. r4.1 Table 22 says no iordy on PIO5 and PIO6.  */
1779 	if (ata_id_is_cfa(adev->id)
1780 	    && (adev->pio_mode == XFER_PIO_5 || adev->pio_mode == XFER_PIO_6))
1781 		return 0;
1782 	/* PIO3 and higher it is mandatory */
1783 	if (adev->pio_mode > XFER_PIO_2)
1784 		return 1;
1785 	/* We turn it on when possible */
1786 	if (ata_id_has_iordy(adev->id))
1787 		return 1;
1788 	return 0;
1789 }
1790 
1791 /**
1792  *	ata_pio_mask_no_iordy	-	Return the non IORDY mask
1793  *	@adev: ATA device
1794  *
1795  *	Compute the highest mode possible if we are not using iordy. Return
1796  *	-1 if no iordy mode is available.
1797  */
1798 static u32 ata_pio_mask_no_iordy(const struct ata_device *adev)
1799 {
1800 	/* If we have no drive specific rule, then PIO 2 is non IORDY */
1801 	if (adev->id[ATA_ID_FIELD_VALID] & 2) {	/* EIDE */
1802 		u16 pio = adev->id[ATA_ID_EIDE_PIO];
1803 		/* Is the speed faster than the drive allows non IORDY ? */
1804 		if (pio) {
1805 			/* This is cycle times not frequency - watch the logic! */
1806 			if (pio > 240)	/* PIO2 is 240nS per cycle */
1807 				return 3 << ATA_SHIFT_PIO;
1808 			return 7 << ATA_SHIFT_PIO;
1809 		}
1810 	}
1811 	return 3 << ATA_SHIFT_PIO;
1812 }
1813 
1814 /**
1815  *	ata_do_dev_read_id		-	default ID read method
1816  *	@dev: device
1817  *	@tf: proposed taskfile
1818  *	@id: data buffer
1819  *
1820  *	Issue the identify taskfile and hand back the buffer containing
1821  *	identify data. For some RAID controllers and for pre ATA devices
1822  *	this function is wrapped or replaced by the driver
1823  */
1824 unsigned int ata_do_dev_read_id(struct ata_device *dev,
1825 					struct ata_taskfile *tf, u16 *id)
1826 {
1827 	return ata_exec_internal(dev, tf, NULL, DMA_FROM_DEVICE,
1828 				     id, sizeof(id[0]) * ATA_ID_WORDS, 0);
1829 }
1830 
1831 /**
1832  *	ata_dev_read_id - Read ID data from the specified device
1833  *	@dev: target device
1834  *	@p_class: pointer to class of the target device (may be changed)
1835  *	@flags: ATA_READID_* flags
1836  *	@id: buffer to read IDENTIFY data into
1837  *
1838  *	Read ID data from the specified device.  ATA_CMD_ID_ATA is
1839  *	performed on ATA devices and ATA_CMD_ID_ATAPI on ATAPI
1840  *	devices.  This function also issues ATA_CMD_INIT_DEV_PARAMS
1841  *	for pre-ATA4 drives.
1842  *
1843  *	FIXME: ATA_CMD_ID_ATA is optional for early drives and right
1844  *	now we abort if we hit that case.
1845  *
1846  *	LOCKING:
1847  *	Kernel thread context (may sleep)
1848  *
1849  *	RETURNS:
1850  *	0 on success, -errno otherwise.
1851  */
1852 int ata_dev_read_id(struct ata_device *dev, unsigned int *p_class,
1853 		    unsigned int flags, u16 *id)
1854 {
1855 	struct ata_port *ap = dev->link->ap;
1856 	unsigned int class = *p_class;
1857 	struct ata_taskfile tf;
1858 	unsigned int err_mask = 0;
1859 	const char *reason;
1860 	bool is_semb = class == ATA_DEV_SEMB;
1861 	int may_fallback = 1, tried_spinup = 0;
1862 	int rc;
1863 
1864 	if (ata_msg_ctl(ap))
1865 		ata_dev_dbg(dev, "%s: ENTER\n", __func__);
1866 
1867 retry:
1868 	ata_tf_init(dev, &tf);
1869 
1870 	switch (class) {
1871 	case ATA_DEV_SEMB:
1872 		class = ATA_DEV_ATA;	/* some hard drives report SEMB sig */
1873 	case ATA_DEV_ATA:
1874 	case ATA_DEV_ZAC:
1875 		tf.command = ATA_CMD_ID_ATA;
1876 		break;
1877 	case ATA_DEV_ATAPI:
1878 		tf.command = ATA_CMD_ID_ATAPI;
1879 		break;
1880 	default:
1881 		rc = -ENODEV;
1882 		reason = "unsupported class";
1883 		goto err_out;
1884 	}
1885 
1886 	tf.protocol = ATA_PROT_PIO;
1887 
1888 	/* Some devices choke if TF registers contain garbage.  Make
1889 	 * sure those are properly initialized.
1890 	 */
1891 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1892 
1893 	/* Device presence detection is unreliable on some
1894 	 * controllers.  Always poll IDENTIFY if available.
1895 	 */
1896 	tf.flags |= ATA_TFLAG_POLLING;
1897 
1898 	if (ap->ops->read_id)
1899 		err_mask = ap->ops->read_id(dev, &tf, id);
1900 	else
1901 		err_mask = ata_do_dev_read_id(dev, &tf, id);
1902 
1903 	if (err_mask) {
1904 		if (err_mask & AC_ERR_NODEV_HINT) {
1905 			ata_dev_dbg(dev, "NODEV after polling detection\n");
1906 			return -ENOENT;
1907 		}
1908 
1909 		if (is_semb) {
1910 			ata_dev_info(dev,
1911 		     "IDENTIFY failed on device w/ SEMB sig, disabled\n");
1912 			/* SEMB is not supported yet */
1913 			*p_class = ATA_DEV_SEMB_UNSUP;
1914 			return 0;
1915 		}
1916 
1917 		if ((err_mask == AC_ERR_DEV) && (tf.feature & ATA_ABORTED)) {
1918 			/* Device or controller might have reported
1919 			 * the wrong device class.  Give a shot at the
1920 			 * other IDENTIFY if the current one is
1921 			 * aborted by the device.
1922 			 */
1923 			if (may_fallback) {
1924 				may_fallback = 0;
1925 
1926 				if (class == ATA_DEV_ATA)
1927 					class = ATA_DEV_ATAPI;
1928 				else
1929 					class = ATA_DEV_ATA;
1930 				goto retry;
1931 			}
1932 
1933 			/* Control reaches here iff the device aborted
1934 			 * both flavors of IDENTIFYs which happens
1935 			 * sometimes with phantom devices.
1936 			 */
1937 			ata_dev_dbg(dev,
1938 				    "both IDENTIFYs aborted, assuming NODEV\n");
1939 			return -ENOENT;
1940 		}
1941 
1942 		rc = -EIO;
1943 		reason = "I/O error";
1944 		goto err_out;
1945 	}
1946 
1947 	if (dev->horkage & ATA_HORKAGE_DUMP_ID) {
1948 		ata_dev_dbg(dev, "dumping IDENTIFY data, "
1949 			    "class=%d may_fallback=%d tried_spinup=%d\n",
1950 			    class, may_fallback, tried_spinup);
1951 		print_hex_dump(KERN_DEBUG, "", DUMP_PREFIX_OFFSET,
1952 			       16, 2, id, ATA_ID_WORDS * sizeof(*id), true);
1953 	}
1954 
1955 	/* Falling back doesn't make sense if ID data was read
1956 	 * successfully at least once.
1957 	 */
1958 	may_fallback = 0;
1959 
1960 	swap_buf_le16(id, ATA_ID_WORDS);
1961 
1962 	/* sanity check */
1963 	rc = -EINVAL;
1964 	reason = "device reports invalid type";
1965 
1966 	if (class == ATA_DEV_ATA || class == ATA_DEV_ZAC) {
1967 		if (!ata_id_is_ata(id) && !ata_id_is_cfa(id))
1968 			goto err_out;
1969 		if (ap->host->flags & ATA_HOST_IGNORE_ATA &&
1970 							ata_id_is_ata(id)) {
1971 			ata_dev_dbg(dev,
1972 				"host indicates ignore ATA devices, ignored\n");
1973 			return -ENOENT;
1974 		}
1975 	} else {
1976 		if (ata_id_is_ata(id))
1977 			goto err_out;
1978 	}
1979 
1980 	if (!tried_spinup && (id[2] == 0x37c8 || id[2] == 0x738c)) {
1981 		tried_spinup = 1;
1982 		/*
1983 		 * Drive powered-up in standby mode, and requires a specific
1984 		 * SET_FEATURES spin-up subcommand before it will accept
1985 		 * anything other than the original IDENTIFY command.
1986 		 */
1987 		err_mask = ata_dev_set_feature(dev, SETFEATURES_SPINUP, 0);
1988 		if (err_mask && id[2] != 0x738c) {
1989 			rc = -EIO;
1990 			reason = "SPINUP failed";
1991 			goto err_out;
1992 		}
1993 		/*
1994 		 * If the drive initially returned incomplete IDENTIFY info,
1995 		 * we now must reissue the IDENTIFY command.
1996 		 */
1997 		if (id[2] == 0x37c8)
1998 			goto retry;
1999 	}
2000 
2001 	if ((flags & ATA_READID_POSTRESET) &&
2002 	    (class == ATA_DEV_ATA || class == ATA_DEV_ZAC)) {
2003 		/*
2004 		 * The exact sequence expected by certain pre-ATA4 drives is:
2005 		 * SRST RESET
2006 		 * IDENTIFY (optional in early ATA)
2007 		 * INITIALIZE DEVICE PARAMETERS (later IDE and ATA)
2008 		 * anything else..
2009 		 * Some drives were very specific about that exact sequence.
2010 		 *
2011 		 * Note that ATA4 says lba is mandatory so the second check
2012 		 * should never trigger.
2013 		 */
2014 		if (ata_id_major_version(id) < 4 || !ata_id_has_lba(id)) {
2015 			err_mask = ata_dev_init_params(dev, id[3], id[6]);
2016 			if (err_mask) {
2017 				rc = -EIO;
2018 				reason = "INIT_DEV_PARAMS failed";
2019 				goto err_out;
2020 			}
2021 
2022 			/* current CHS translation info (id[53-58]) might be
2023 			 * changed. reread the identify device info.
2024 			 */
2025 			flags &= ~ATA_READID_POSTRESET;
2026 			goto retry;
2027 		}
2028 	}
2029 
2030 	*p_class = class;
2031 
2032 	return 0;
2033 
2034  err_out:
2035 	if (ata_msg_warn(ap))
2036 		ata_dev_warn(dev, "failed to IDENTIFY (%s, err_mask=0x%x)\n",
2037 			     reason, err_mask);
2038 	return rc;
2039 }
2040 
2041 static int ata_do_link_spd_horkage(struct ata_device *dev)
2042 {
2043 	struct ata_link *plink = ata_dev_phys_link(dev);
2044 	u32 target, target_limit;
2045 
2046 	if (!sata_scr_valid(plink))
2047 		return 0;
2048 
2049 	if (dev->horkage & ATA_HORKAGE_1_5_GBPS)
2050 		target = 1;
2051 	else
2052 		return 0;
2053 
2054 	target_limit = (1 << target) - 1;
2055 
2056 	/* if already on stricter limit, no need to push further */
2057 	if (plink->sata_spd_limit <= target_limit)
2058 		return 0;
2059 
2060 	plink->sata_spd_limit = target_limit;
2061 
2062 	/* Request another EH round by returning -EAGAIN if link is
2063 	 * going faster than the target speed.  Forward progress is
2064 	 * guaranteed by setting sata_spd_limit to target_limit above.
2065 	 */
2066 	if (plink->sata_spd > target) {
2067 		ata_dev_info(dev, "applying link speed limit horkage to %s\n",
2068 			     sata_spd_string(target));
2069 		return -EAGAIN;
2070 	}
2071 	return 0;
2072 }
2073 
2074 static inline u8 ata_dev_knobble(struct ata_device *dev)
2075 {
2076 	struct ata_port *ap = dev->link->ap;
2077 
2078 	if (ata_dev_blacklisted(dev) & ATA_HORKAGE_BRIDGE_OK)
2079 		return 0;
2080 
2081 	return ((ap->cbl == ATA_CBL_SATA) && (!ata_id_is_sata(dev->id)));
2082 }
2083 
2084 static void ata_dev_config_ncq_send_recv(struct ata_device *dev)
2085 {
2086 	struct ata_port *ap = dev->link->ap;
2087 	unsigned int err_mask;
2088 	int log_index = ATA_LOG_NCQ_SEND_RECV * 2;
2089 	u16 log_pages;
2090 
2091 	err_mask = ata_read_log_page(dev, ATA_LOG_DIRECTORY,
2092 				     0, ap->sector_buf, 1);
2093 	if (err_mask) {
2094 		ata_dev_dbg(dev,
2095 			    "failed to get Log Directory Emask 0x%x\n",
2096 			    err_mask);
2097 		return;
2098 	}
2099 	log_pages = get_unaligned_le16(&ap->sector_buf[log_index]);
2100 	if (!log_pages) {
2101 		ata_dev_warn(dev,
2102 			     "NCQ Send/Recv Log not supported\n");
2103 		return;
2104 	}
2105 	err_mask = ata_read_log_page(dev, ATA_LOG_NCQ_SEND_RECV,
2106 				     0, ap->sector_buf, 1);
2107 	if (err_mask) {
2108 		ata_dev_dbg(dev,
2109 			    "failed to get NCQ Send/Recv Log Emask 0x%x\n",
2110 			    err_mask);
2111 	} else {
2112 		u8 *cmds = dev->ncq_send_recv_cmds;
2113 
2114 		dev->flags |= ATA_DFLAG_NCQ_SEND_RECV;
2115 		memcpy(cmds, ap->sector_buf, ATA_LOG_NCQ_SEND_RECV_SIZE);
2116 
2117 		if (dev->horkage & ATA_HORKAGE_NO_NCQ_TRIM) {
2118 			ata_dev_dbg(dev, "disabling queued TRIM support\n");
2119 			cmds[ATA_LOG_NCQ_SEND_RECV_DSM_OFFSET] &=
2120 				~ATA_LOG_NCQ_SEND_RECV_DSM_TRIM;
2121 		}
2122 	}
2123 }
2124 
2125 static void ata_dev_config_ncq_non_data(struct ata_device *dev)
2126 {
2127 	struct ata_port *ap = dev->link->ap;
2128 	unsigned int err_mask;
2129 	int log_index = ATA_LOG_NCQ_NON_DATA * 2;
2130 	u16 log_pages;
2131 
2132 	err_mask = ata_read_log_page(dev, ATA_LOG_DIRECTORY,
2133 				     0, ap->sector_buf, 1);
2134 	if (err_mask) {
2135 		ata_dev_dbg(dev,
2136 			    "failed to get Log Directory Emask 0x%x\n",
2137 			    err_mask);
2138 		return;
2139 	}
2140 	log_pages = get_unaligned_le16(&ap->sector_buf[log_index]);
2141 	if (!log_pages) {
2142 		ata_dev_warn(dev,
2143 			     "NCQ Send/Recv Log not supported\n");
2144 		return;
2145 	}
2146 	err_mask = ata_read_log_page(dev, ATA_LOG_NCQ_NON_DATA,
2147 				     0, ap->sector_buf, 1);
2148 	if (err_mask) {
2149 		ata_dev_dbg(dev,
2150 			    "failed to get NCQ Non-Data Log Emask 0x%x\n",
2151 			    err_mask);
2152 	} else {
2153 		u8 *cmds = dev->ncq_non_data_cmds;
2154 
2155 		memcpy(cmds, ap->sector_buf, ATA_LOG_NCQ_NON_DATA_SIZE);
2156 	}
2157 }
2158 
2159 static int ata_dev_config_ncq(struct ata_device *dev,
2160 			       char *desc, size_t desc_sz)
2161 {
2162 	struct ata_port *ap = dev->link->ap;
2163 	int hdepth = 0, ddepth = ata_id_queue_depth(dev->id);
2164 	unsigned int err_mask;
2165 	char *aa_desc = "";
2166 
2167 	if (!ata_id_has_ncq(dev->id)) {
2168 		desc[0] = '\0';
2169 		return 0;
2170 	}
2171 	if (dev->horkage & ATA_HORKAGE_NONCQ) {
2172 		snprintf(desc, desc_sz, "NCQ (not used)");
2173 		return 0;
2174 	}
2175 	if (ap->flags & ATA_FLAG_NCQ) {
2176 		hdepth = min(ap->scsi_host->can_queue, ATA_MAX_QUEUE - 1);
2177 		dev->flags |= ATA_DFLAG_NCQ;
2178 	}
2179 
2180 	if (!(dev->horkage & ATA_HORKAGE_BROKEN_FPDMA_AA) &&
2181 		(ap->flags & ATA_FLAG_FPDMA_AA) &&
2182 		ata_id_has_fpdma_aa(dev->id)) {
2183 		err_mask = ata_dev_set_feature(dev, SETFEATURES_SATA_ENABLE,
2184 			SATA_FPDMA_AA);
2185 		if (err_mask) {
2186 			ata_dev_err(dev,
2187 				    "failed to enable AA (error_mask=0x%x)\n",
2188 				    err_mask);
2189 			if (err_mask != AC_ERR_DEV) {
2190 				dev->horkage |= ATA_HORKAGE_BROKEN_FPDMA_AA;
2191 				return -EIO;
2192 			}
2193 		} else
2194 			aa_desc = ", AA";
2195 	}
2196 
2197 	if (hdepth >= ddepth)
2198 		snprintf(desc, desc_sz, "NCQ (depth %d)%s", ddepth, aa_desc);
2199 	else
2200 		snprintf(desc, desc_sz, "NCQ (depth %d/%d)%s", hdepth,
2201 			ddepth, aa_desc);
2202 
2203 	if ((ap->flags & ATA_FLAG_FPDMA_AUX)) {
2204 		if (ata_id_has_ncq_send_and_recv(dev->id))
2205 			ata_dev_config_ncq_send_recv(dev);
2206 		if (ata_id_has_ncq_non_data(dev->id))
2207 			ata_dev_config_ncq_non_data(dev);
2208 	}
2209 
2210 	return 0;
2211 }
2212 
2213 static void ata_dev_config_sense_reporting(struct ata_device *dev)
2214 {
2215 	unsigned int err_mask;
2216 
2217 	if (!ata_id_has_sense_reporting(dev->id))
2218 		return;
2219 
2220 	if (ata_id_sense_reporting_enabled(dev->id))
2221 		return;
2222 
2223 	err_mask = ata_dev_set_feature(dev, SETFEATURE_SENSE_DATA, 0x1);
2224 	if (err_mask) {
2225 		ata_dev_dbg(dev,
2226 			    "failed to enable Sense Data Reporting, Emask 0x%x\n",
2227 			    err_mask);
2228 	}
2229 }
2230 
2231 static void ata_dev_config_zac(struct ata_device *dev)
2232 {
2233 	struct ata_port *ap = dev->link->ap;
2234 	unsigned int err_mask;
2235 	u8 *identify_buf = ap->sector_buf;
2236 	int log_index = ATA_LOG_SATA_ID_DEV_DATA * 2, i, found = 0;
2237 	u16 log_pages;
2238 
2239 	dev->zac_zones_optimal_open = U32_MAX;
2240 	dev->zac_zones_optimal_nonseq = U32_MAX;
2241 	dev->zac_zones_max_open = U32_MAX;
2242 
2243 	/*
2244 	 * Always set the 'ZAC' flag for Host-managed devices.
2245 	 */
2246 	if (dev->class == ATA_DEV_ZAC)
2247 		dev->flags |= ATA_DFLAG_ZAC;
2248 	else if (ata_id_zoned_cap(dev->id) == 0x01)
2249 		/*
2250 		 * Check for host-aware devices.
2251 		 */
2252 		dev->flags |= ATA_DFLAG_ZAC;
2253 
2254 	if (!(dev->flags & ATA_DFLAG_ZAC))
2255 		return;
2256 
2257 	/*
2258 	 * Read Log Directory to figure out if IDENTIFY DEVICE log
2259 	 * is supported.
2260 	 */
2261 	err_mask = ata_read_log_page(dev, ATA_LOG_DIRECTORY,
2262 				     0, ap->sector_buf, 1);
2263 	if (err_mask) {
2264 		ata_dev_info(dev,
2265 			     "failed to get Log Directory Emask 0x%x\n",
2266 			     err_mask);
2267 		return;
2268 	}
2269 	log_pages = get_unaligned_le16(&ap->sector_buf[log_index]);
2270 	if (log_pages == 0) {
2271 		ata_dev_warn(dev,
2272 			     "ATA Identify Device Log not supported\n");
2273 		return;
2274 	}
2275 	/*
2276 	 * Read IDENTIFY DEVICE data log, page 0, to figure out
2277 	 * if page 9 is supported.
2278 	 */
2279 	err_mask = ata_read_log_page(dev, ATA_LOG_SATA_ID_DEV_DATA, 0,
2280 				     identify_buf, 1);
2281 	if (err_mask) {
2282 		ata_dev_info(dev,
2283 			     "failed to get Device Identify Log Emask 0x%x\n",
2284 			     err_mask);
2285 		return;
2286 	}
2287 	log_pages = identify_buf[8];
2288 	for (i = 0; i < log_pages; i++) {
2289 		if (identify_buf[9 + i] == ATA_LOG_ZONED_INFORMATION) {
2290 			found++;
2291 			break;
2292 		}
2293 	}
2294 	if (!found) {
2295 		ata_dev_warn(dev,
2296 			     "ATA Zoned Information Log not supported\n");
2297 		return;
2298 	}
2299 
2300 	/*
2301 	 * Read IDENTIFY DEVICE data log, page 9 (Zoned-device information)
2302 	 */
2303 	err_mask = ata_read_log_page(dev, ATA_LOG_SATA_ID_DEV_DATA,
2304 				     ATA_LOG_ZONED_INFORMATION,
2305 				     identify_buf, 1);
2306 	if (!err_mask) {
2307 		u64 zoned_cap, opt_open, opt_nonseq, max_open;
2308 
2309 		zoned_cap = get_unaligned_le64(&identify_buf[8]);
2310 		if ((zoned_cap >> 63))
2311 			dev->zac_zoned_cap = (zoned_cap & 1);
2312 		opt_open = get_unaligned_le64(&identify_buf[24]);
2313 		if ((opt_open >> 63))
2314 			dev->zac_zones_optimal_open = (u32)opt_open;
2315 		opt_nonseq = get_unaligned_le64(&identify_buf[32]);
2316 		if ((opt_nonseq >> 63))
2317 			dev->zac_zones_optimal_nonseq = (u32)opt_nonseq;
2318 		max_open = get_unaligned_le64(&identify_buf[40]);
2319 		if ((max_open >> 63))
2320 			dev->zac_zones_max_open = (u32)max_open;
2321 	}
2322 }
2323 
2324 /**
2325  *	ata_dev_configure - Configure the specified ATA/ATAPI device
2326  *	@dev: Target device to configure
2327  *
2328  *	Configure @dev according to @dev->id.  Generic and low-level
2329  *	driver specific fixups are also applied.
2330  *
2331  *	LOCKING:
2332  *	Kernel thread context (may sleep)
2333  *
2334  *	RETURNS:
2335  *	0 on success, -errno otherwise
2336  */
2337 int ata_dev_configure(struct ata_device *dev)
2338 {
2339 	struct ata_port *ap = dev->link->ap;
2340 	struct ata_eh_context *ehc = &dev->link->eh_context;
2341 	int print_info = ehc->i.flags & ATA_EHI_PRINTINFO;
2342 	const u16 *id = dev->id;
2343 	unsigned long xfer_mask;
2344 	unsigned int err_mask;
2345 	char revbuf[7];		/* XYZ-99\0 */
2346 	char fwrevbuf[ATA_ID_FW_REV_LEN+1];
2347 	char modelbuf[ATA_ID_PROD_LEN+1];
2348 	int rc;
2349 
2350 	if (!ata_dev_enabled(dev) && ata_msg_info(ap)) {
2351 		ata_dev_info(dev, "%s: ENTER/EXIT -- nodev\n", __func__);
2352 		return 0;
2353 	}
2354 
2355 	if (ata_msg_probe(ap))
2356 		ata_dev_dbg(dev, "%s: ENTER\n", __func__);
2357 
2358 	/* set horkage */
2359 	dev->horkage |= ata_dev_blacklisted(dev);
2360 	ata_force_horkage(dev);
2361 
2362 	if (dev->horkage & ATA_HORKAGE_DISABLE) {
2363 		ata_dev_info(dev, "unsupported device, disabling\n");
2364 		ata_dev_disable(dev);
2365 		return 0;
2366 	}
2367 
2368 	if ((!atapi_enabled || (ap->flags & ATA_FLAG_NO_ATAPI)) &&
2369 	    dev->class == ATA_DEV_ATAPI) {
2370 		ata_dev_warn(dev, "WARNING: ATAPI is %s, device ignored\n",
2371 			     atapi_enabled ? "not supported with this driver"
2372 			     : "disabled");
2373 		ata_dev_disable(dev);
2374 		return 0;
2375 	}
2376 
2377 	rc = ata_do_link_spd_horkage(dev);
2378 	if (rc)
2379 		return rc;
2380 
2381 	/* some WD SATA-1 drives have issues with LPM, turn on NOLPM for them */
2382 	if ((dev->horkage & ATA_HORKAGE_WD_BROKEN_LPM) &&
2383 	    (id[ATA_ID_SATA_CAPABILITY] & 0xe) == 0x2)
2384 		dev->horkage |= ATA_HORKAGE_NOLPM;
2385 
2386 	if (dev->horkage & ATA_HORKAGE_NOLPM) {
2387 		ata_dev_warn(dev, "LPM support broken, forcing max_power\n");
2388 		dev->link->ap->target_lpm_policy = ATA_LPM_MAX_POWER;
2389 	}
2390 
2391 	/* let ACPI work its magic */
2392 	rc = ata_acpi_on_devcfg(dev);
2393 	if (rc)
2394 		return rc;
2395 
2396 	/* massage HPA, do it early as it might change IDENTIFY data */
2397 	rc = ata_hpa_resize(dev);
2398 	if (rc)
2399 		return rc;
2400 
2401 	/* print device capabilities */
2402 	if (ata_msg_probe(ap))
2403 		ata_dev_dbg(dev,
2404 			    "%s: cfg 49:%04x 82:%04x 83:%04x 84:%04x "
2405 			    "85:%04x 86:%04x 87:%04x 88:%04x\n",
2406 			    __func__,
2407 			    id[49], id[82], id[83], id[84],
2408 			    id[85], id[86], id[87], id[88]);
2409 
2410 	/* initialize to-be-configured parameters */
2411 	dev->flags &= ~ATA_DFLAG_CFG_MASK;
2412 	dev->max_sectors = 0;
2413 	dev->cdb_len = 0;
2414 	dev->n_sectors = 0;
2415 	dev->cylinders = 0;
2416 	dev->heads = 0;
2417 	dev->sectors = 0;
2418 	dev->multi_count = 0;
2419 
2420 	/*
2421 	 * common ATA, ATAPI feature tests
2422 	 */
2423 
2424 	/* find max transfer mode; for printk only */
2425 	xfer_mask = ata_id_xfermask(id);
2426 
2427 	if (ata_msg_probe(ap))
2428 		ata_dump_id(id);
2429 
2430 	/* SCSI only uses 4-char revisions, dump full 8 chars from ATA */
2431 	ata_id_c_string(dev->id, fwrevbuf, ATA_ID_FW_REV,
2432 			sizeof(fwrevbuf));
2433 
2434 	ata_id_c_string(dev->id, modelbuf, ATA_ID_PROD,
2435 			sizeof(modelbuf));
2436 
2437 	/* ATA-specific feature tests */
2438 	if (dev->class == ATA_DEV_ATA || dev->class == ATA_DEV_ZAC) {
2439 		if (ata_id_is_cfa(id)) {
2440 			/* CPRM may make this media unusable */
2441 			if (id[ATA_ID_CFA_KEY_MGMT] & 1)
2442 				ata_dev_warn(dev,
2443 	"supports DRM functions and may not be fully accessible\n");
2444 			snprintf(revbuf, 7, "CFA");
2445 		} else {
2446 			snprintf(revbuf, 7, "ATA-%d", ata_id_major_version(id));
2447 			/* Warn the user if the device has TPM extensions */
2448 			if (ata_id_has_tpm(id))
2449 				ata_dev_warn(dev,
2450 	"supports DRM functions and may not be fully accessible\n");
2451 		}
2452 
2453 		dev->n_sectors = ata_id_n_sectors(id);
2454 
2455 		/* get current R/W Multiple count setting */
2456 		if ((dev->id[47] >> 8) == 0x80 && (dev->id[59] & 0x100)) {
2457 			unsigned int max = dev->id[47] & 0xff;
2458 			unsigned int cnt = dev->id[59] & 0xff;
2459 			/* only recognize/allow powers of two here */
2460 			if (is_power_of_2(max) && is_power_of_2(cnt))
2461 				if (cnt <= max)
2462 					dev->multi_count = cnt;
2463 		}
2464 
2465 		if (ata_id_has_lba(id)) {
2466 			const char *lba_desc;
2467 			char ncq_desc[24];
2468 
2469 			lba_desc = "LBA";
2470 			dev->flags |= ATA_DFLAG_LBA;
2471 			if (ata_id_has_lba48(id)) {
2472 				dev->flags |= ATA_DFLAG_LBA48;
2473 				lba_desc = "LBA48";
2474 
2475 				if (dev->n_sectors >= (1UL << 28) &&
2476 				    ata_id_has_flush_ext(id))
2477 					dev->flags |= ATA_DFLAG_FLUSH_EXT;
2478 			}
2479 
2480 			/* config NCQ */
2481 			rc = ata_dev_config_ncq(dev, ncq_desc, sizeof(ncq_desc));
2482 			if (rc)
2483 				return rc;
2484 
2485 			/* print device info to dmesg */
2486 			if (ata_msg_drv(ap) && print_info) {
2487 				ata_dev_info(dev, "%s: %s, %s, max %s\n",
2488 					     revbuf, modelbuf, fwrevbuf,
2489 					     ata_mode_string(xfer_mask));
2490 				ata_dev_info(dev,
2491 					     "%llu sectors, multi %u: %s %s\n",
2492 					(unsigned long long)dev->n_sectors,
2493 					dev->multi_count, lba_desc, ncq_desc);
2494 			}
2495 		} else {
2496 			/* CHS */
2497 
2498 			/* Default translation */
2499 			dev->cylinders	= id[1];
2500 			dev->heads	= id[3];
2501 			dev->sectors	= id[6];
2502 
2503 			if (ata_id_current_chs_valid(id)) {
2504 				/* Current CHS translation is valid. */
2505 				dev->cylinders = id[54];
2506 				dev->heads     = id[55];
2507 				dev->sectors   = id[56];
2508 			}
2509 
2510 			/* print device info to dmesg */
2511 			if (ata_msg_drv(ap) && print_info) {
2512 				ata_dev_info(dev, "%s: %s, %s, max %s\n",
2513 					     revbuf,	modelbuf, fwrevbuf,
2514 					     ata_mode_string(xfer_mask));
2515 				ata_dev_info(dev,
2516 					     "%llu sectors, multi %u, CHS %u/%u/%u\n",
2517 					     (unsigned long long)dev->n_sectors,
2518 					     dev->multi_count, dev->cylinders,
2519 					     dev->heads, dev->sectors);
2520 			}
2521 		}
2522 
2523 		/* Check and mark DevSlp capability. Get DevSlp timing variables
2524 		 * from SATA Settings page of Identify Device Data Log.
2525 		 */
2526 		if (ata_id_has_devslp(dev->id)) {
2527 			u8 *sata_setting = ap->sector_buf;
2528 			int i, j;
2529 
2530 			dev->flags |= ATA_DFLAG_DEVSLP;
2531 			err_mask = ata_read_log_page(dev,
2532 						     ATA_LOG_SATA_ID_DEV_DATA,
2533 						     ATA_LOG_SATA_SETTINGS,
2534 						     sata_setting,
2535 						     1);
2536 			if (err_mask)
2537 				ata_dev_dbg(dev,
2538 					    "failed to get Identify Device Data, Emask 0x%x\n",
2539 					    err_mask);
2540 			else
2541 				for (i = 0; i < ATA_LOG_DEVSLP_SIZE; i++) {
2542 					j = ATA_LOG_DEVSLP_OFFSET + i;
2543 					dev->devslp_timing[i] = sata_setting[j];
2544 				}
2545 		}
2546 		ata_dev_config_sense_reporting(dev);
2547 		ata_dev_config_zac(dev);
2548 		dev->cdb_len = 16;
2549 	}
2550 
2551 	/* ATAPI-specific feature tests */
2552 	else if (dev->class == ATA_DEV_ATAPI) {
2553 		const char *cdb_intr_string = "";
2554 		const char *atapi_an_string = "";
2555 		const char *dma_dir_string = "";
2556 		u32 sntf;
2557 
2558 		rc = atapi_cdb_len(id);
2559 		if ((rc < 12) || (rc > ATAPI_CDB_LEN)) {
2560 			if (ata_msg_warn(ap))
2561 				ata_dev_warn(dev, "unsupported CDB len\n");
2562 			rc = -EINVAL;
2563 			goto err_out_nosup;
2564 		}
2565 		dev->cdb_len = (unsigned int) rc;
2566 
2567 		/* Enable ATAPI AN if both the host and device have
2568 		 * the support.  If PMP is attached, SNTF is required
2569 		 * to enable ATAPI AN to discern between PHY status
2570 		 * changed notifications and ATAPI ANs.
2571 		 */
2572 		if (atapi_an &&
2573 		    (ap->flags & ATA_FLAG_AN) && ata_id_has_atapi_AN(id) &&
2574 		    (!sata_pmp_attached(ap) ||
2575 		     sata_scr_read(&ap->link, SCR_NOTIFICATION, &sntf) == 0)) {
2576 			/* issue SET feature command to turn this on */
2577 			err_mask = ata_dev_set_feature(dev,
2578 					SETFEATURES_SATA_ENABLE, SATA_AN);
2579 			if (err_mask)
2580 				ata_dev_err(dev,
2581 					    "failed to enable ATAPI AN (err_mask=0x%x)\n",
2582 					    err_mask);
2583 			else {
2584 				dev->flags |= ATA_DFLAG_AN;
2585 				atapi_an_string = ", ATAPI AN";
2586 			}
2587 		}
2588 
2589 		if (ata_id_cdb_intr(dev->id)) {
2590 			dev->flags |= ATA_DFLAG_CDB_INTR;
2591 			cdb_intr_string = ", CDB intr";
2592 		}
2593 
2594 		if (atapi_dmadir || (dev->horkage & ATA_HORKAGE_ATAPI_DMADIR) || atapi_id_dmadir(dev->id)) {
2595 			dev->flags |= ATA_DFLAG_DMADIR;
2596 			dma_dir_string = ", DMADIR";
2597 		}
2598 
2599 		if (ata_id_has_da(dev->id)) {
2600 			dev->flags |= ATA_DFLAG_DA;
2601 			zpodd_init(dev);
2602 		}
2603 
2604 		/* print device info to dmesg */
2605 		if (ata_msg_drv(ap) && print_info)
2606 			ata_dev_info(dev,
2607 				     "ATAPI: %s, %s, max %s%s%s%s\n",
2608 				     modelbuf, fwrevbuf,
2609 				     ata_mode_string(xfer_mask),
2610 				     cdb_intr_string, atapi_an_string,
2611 				     dma_dir_string);
2612 	}
2613 
2614 	/* determine max_sectors */
2615 	dev->max_sectors = ATA_MAX_SECTORS;
2616 	if (dev->flags & ATA_DFLAG_LBA48)
2617 		dev->max_sectors = ATA_MAX_SECTORS_LBA48;
2618 
2619 	/* Limit PATA drive on SATA cable bridge transfers to udma5,
2620 	   200 sectors */
2621 	if (ata_dev_knobble(dev)) {
2622 		if (ata_msg_drv(ap) && print_info)
2623 			ata_dev_info(dev, "applying bridge limits\n");
2624 		dev->udma_mask &= ATA_UDMA5;
2625 		dev->max_sectors = ATA_MAX_SECTORS;
2626 	}
2627 
2628 	if ((dev->class == ATA_DEV_ATAPI) &&
2629 	    (atapi_command_packet_set(id) == TYPE_TAPE)) {
2630 		dev->max_sectors = ATA_MAX_SECTORS_TAPE;
2631 		dev->horkage |= ATA_HORKAGE_STUCK_ERR;
2632 	}
2633 
2634 	if (dev->horkage & ATA_HORKAGE_MAX_SEC_128)
2635 		dev->max_sectors = min_t(unsigned int, ATA_MAX_SECTORS_128,
2636 					 dev->max_sectors);
2637 
2638 	if (dev->horkage & ATA_HORKAGE_MAX_SEC_1024)
2639 		dev->max_sectors = min_t(unsigned int, ATA_MAX_SECTORS_1024,
2640 					 dev->max_sectors);
2641 
2642 	if (dev->horkage & ATA_HORKAGE_MAX_SEC_LBA48)
2643 		dev->max_sectors = ATA_MAX_SECTORS_LBA48;
2644 
2645 	if (ap->ops->dev_config)
2646 		ap->ops->dev_config(dev);
2647 
2648 	if (dev->horkage & ATA_HORKAGE_DIAGNOSTIC) {
2649 		/* Let the user know. We don't want to disallow opens for
2650 		   rescue purposes, or in case the vendor is just a blithering
2651 		   idiot. Do this after the dev_config call as some controllers
2652 		   with buggy firmware may want to avoid reporting false device
2653 		   bugs */
2654 
2655 		if (print_info) {
2656 			ata_dev_warn(dev,
2657 "Drive reports diagnostics failure. This may indicate a drive\n");
2658 			ata_dev_warn(dev,
2659 "fault or invalid emulation. Contact drive vendor for information.\n");
2660 		}
2661 	}
2662 
2663 	if ((dev->horkage & ATA_HORKAGE_FIRMWARE_WARN) && print_info) {
2664 		ata_dev_warn(dev, "WARNING: device requires firmware update to be fully functional\n");
2665 		ata_dev_warn(dev, "         contact the vendor or visit http://ata.wiki.kernel.org\n");
2666 	}
2667 
2668 	return 0;
2669 
2670 err_out_nosup:
2671 	if (ata_msg_probe(ap))
2672 		ata_dev_dbg(dev, "%s: EXIT, err\n", __func__);
2673 	return rc;
2674 }
2675 
2676 /**
2677  *	ata_cable_40wire	-	return 40 wire cable type
2678  *	@ap: port
2679  *
2680  *	Helper method for drivers which want to hardwire 40 wire cable
2681  *	detection.
2682  */
2683 
2684 int ata_cable_40wire(struct ata_port *ap)
2685 {
2686 	return ATA_CBL_PATA40;
2687 }
2688 
2689 /**
2690  *	ata_cable_80wire	-	return 80 wire cable type
2691  *	@ap: port
2692  *
2693  *	Helper method for drivers which want to hardwire 80 wire cable
2694  *	detection.
2695  */
2696 
2697 int ata_cable_80wire(struct ata_port *ap)
2698 {
2699 	return ATA_CBL_PATA80;
2700 }
2701 
2702 /**
2703  *	ata_cable_unknown	-	return unknown PATA cable.
2704  *	@ap: port
2705  *
2706  *	Helper method for drivers which have no PATA cable detection.
2707  */
2708 
2709 int ata_cable_unknown(struct ata_port *ap)
2710 {
2711 	return ATA_CBL_PATA_UNK;
2712 }
2713 
2714 /**
2715  *	ata_cable_ignore	-	return ignored PATA cable.
2716  *	@ap: port
2717  *
2718  *	Helper method for drivers which don't use cable type to limit
2719  *	transfer mode.
2720  */
2721 int ata_cable_ignore(struct ata_port *ap)
2722 {
2723 	return ATA_CBL_PATA_IGN;
2724 }
2725 
2726 /**
2727  *	ata_cable_sata	-	return SATA cable type
2728  *	@ap: port
2729  *
2730  *	Helper method for drivers which have SATA cables
2731  */
2732 
2733 int ata_cable_sata(struct ata_port *ap)
2734 {
2735 	return ATA_CBL_SATA;
2736 }
2737 
2738 /**
2739  *	ata_bus_probe - Reset and probe ATA bus
2740  *	@ap: Bus to probe
2741  *
2742  *	Master ATA bus probing function.  Initiates a hardware-dependent
2743  *	bus reset, then attempts to identify any devices found on
2744  *	the bus.
2745  *
2746  *	LOCKING:
2747  *	PCI/etc. bus probe sem.
2748  *
2749  *	RETURNS:
2750  *	Zero on success, negative errno otherwise.
2751  */
2752 
2753 int ata_bus_probe(struct ata_port *ap)
2754 {
2755 	unsigned int classes[ATA_MAX_DEVICES];
2756 	int tries[ATA_MAX_DEVICES];
2757 	int rc;
2758 	struct ata_device *dev;
2759 
2760 	ata_for_each_dev(dev, &ap->link, ALL)
2761 		tries[dev->devno] = ATA_PROBE_MAX_TRIES;
2762 
2763  retry:
2764 	ata_for_each_dev(dev, &ap->link, ALL) {
2765 		/* If we issue an SRST then an ATA drive (not ATAPI)
2766 		 * may change configuration and be in PIO0 timing. If
2767 		 * we do a hard reset (or are coming from power on)
2768 		 * this is true for ATA or ATAPI. Until we've set a
2769 		 * suitable controller mode we should not touch the
2770 		 * bus as we may be talking too fast.
2771 		 */
2772 		dev->pio_mode = XFER_PIO_0;
2773 		dev->dma_mode = 0xff;
2774 
2775 		/* If the controller has a pio mode setup function
2776 		 * then use it to set the chipset to rights. Don't
2777 		 * touch the DMA setup as that will be dealt with when
2778 		 * configuring devices.
2779 		 */
2780 		if (ap->ops->set_piomode)
2781 			ap->ops->set_piomode(ap, dev);
2782 	}
2783 
2784 	/* reset and determine device classes */
2785 	ap->ops->phy_reset(ap);
2786 
2787 	ata_for_each_dev(dev, &ap->link, ALL) {
2788 		if (dev->class != ATA_DEV_UNKNOWN)
2789 			classes[dev->devno] = dev->class;
2790 		else
2791 			classes[dev->devno] = ATA_DEV_NONE;
2792 
2793 		dev->class = ATA_DEV_UNKNOWN;
2794 	}
2795 
2796 	/* read IDENTIFY page and configure devices. We have to do the identify
2797 	   specific sequence bass-ackwards so that PDIAG- is released by
2798 	   the slave device */
2799 
2800 	ata_for_each_dev(dev, &ap->link, ALL_REVERSE) {
2801 		if (tries[dev->devno])
2802 			dev->class = classes[dev->devno];
2803 
2804 		if (!ata_dev_enabled(dev))
2805 			continue;
2806 
2807 		rc = ata_dev_read_id(dev, &dev->class, ATA_READID_POSTRESET,
2808 				     dev->id);
2809 		if (rc)
2810 			goto fail;
2811 	}
2812 
2813 	/* Now ask for the cable type as PDIAG- should have been released */
2814 	if (ap->ops->cable_detect)
2815 		ap->cbl = ap->ops->cable_detect(ap);
2816 
2817 	/* We may have SATA bridge glue hiding here irrespective of
2818 	 * the reported cable types and sensed types.  When SATA
2819 	 * drives indicate we have a bridge, we don't know which end
2820 	 * of the link the bridge is which is a problem.
2821 	 */
2822 	ata_for_each_dev(dev, &ap->link, ENABLED)
2823 		if (ata_id_is_sata(dev->id))
2824 			ap->cbl = ATA_CBL_SATA;
2825 
2826 	/* After the identify sequence we can now set up the devices. We do
2827 	   this in the normal order so that the user doesn't get confused */
2828 
2829 	ata_for_each_dev(dev, &ap->link, ENABLED) {
2830 		ap->link.eh_context.i.flags |= ATA_EHI_PRINTINFO;
2831 		rc = ata_dev_configure(dev);
2832 		ap->link.eh_context.i.flags &= ~ATA_EHI_PRINTINFO;
2833 		if (rc)
2834 			goto fail;
2835 	}
2836 
2837 	/* configure transfer mode */
2838 	rc = ata_set_mode(&ap->link, &dev);
2839 	if (rc)
2840 		goto fail;
2841 
2842 	ata_for_each_dev(dev, &ap->link, ENABLED)
2843 		return 0;
2844 
2845 	return -ENODEV;
2846 
2847  fail:
2848 	tries[dev->devno]--;
2849 
2850 	switch (rc) {
2851 	case -EINVAL:
2852 		/* eeek, something went very wrong, give up */
2853 		tries[dev->devno] = 0;
2854 		break;
2855 
2856 	case -ENODEV:
2857 		/* give it just one more chance */
2858 		tries[dev->devno] = min(tries[dev->devno], 1);
2859 	case -EIO:
2860 		if (tries[dev->devno] == 1) {
2861 			/* This is the last chance, better to slow
2862 			 * down than lose it.
2863 			 */
2864 			sata_down_spd_limit(&ap->link, 0);
2865 			ata_down_xfermask_limit(dev, ATA_DNXFER_PIO);
2866 		}
2867 	}
2868 
2869 	if (!tries[dev->devno])
2870 		ata_dev_disable(dev);
2871 
2872 	goto retry;
2873 }
2874 
2875 /**
2876  *	sata_print_link_status - Print SATA link status
2877  *	@link: SATA link to printk link status about
2878  *
2879  *	This function prints link speed and status of a SATA link.
2880  *
2881  *	LOCKING:
2882  *	None.
2883  */
2884 static void sata_print_link_status(struct ata_link *link)
2885 {
2886 	u32 sstatus, scontrol, tmp;
2887 
2888 	if (sata_scr_read(link, SCR_STATUS, &sstatus))
2889 		return;
2890 	sata_scr_read(link, SCR_CONTROL, &scontrol);
2891 
2892 	if (ata_phys_link_online(link)) {
2893 		tmp = (sstatus >> 4) & 0xf;
2894 		ata_link_info(link, "SATA link up %s (SStatus %X SControl %X)\n",
2895 			      sata_spd_string(tmp), sstatus, scontrol);
2896 	} else {
2897 		ata_link_info(link, "SATA link down (SStatus %X SControl %X)\n",
2898 			      sstatus, scontrol);
2899 	}
2900 }
2901 
2902 /**
2903  *	ata_dev_pair		-	return other device on cable
2904  *	@adev: device
2905  *
2906  *	Obtain the other device on the same cable, or if none is
2907  *	present NULL is returned
2908  */
2909 
2910 struct ata_device *ata_dev_pair(struct ata_device *adev)
2911 {
2912 	struct ata_link *link = adev->link;
2913 	struct ata_device *pair = &link->device[1 - adev->devno];
2914 	if (!ata_dev_enabled(pair))
2915 		return NULL;
2916 	return pair;
2917 }
2918 
2919 /**
2920  *	sata_down_spd_limit - adjust SATA spd limit downward
2921  *	@link: Link to adjust SATA spd limit for
2922  *	@spd_limit: Additional limit
2923  *
2924  *	Adjust SATA spd limit of @link downward.  Note that this
2925  *	function only adjusts the limit.  The change must be applied
2926  *	using sata_set_spd().
2927  *
2928  *	If @spd_limit is non-zero, the speed is limited to equal to or
2929  *	lower than @spd_limit if such speed is supported.  If
2930  *	@spd_limit is slower than any supported speed, only the lowest
2931  *	supported speed is allowed.
2932  *
2933  *	LOCKING:
2934  *	Inherited from caller.
2935  *
2936  *	RETURNS:
2937  *	0 on success, negative errno on failure
2938  */
2939 int sata_down_spd_limit(struct ata_link *link, u32 spd_limit)
2940 {
2941 	u32 sstatus, spd, mask;
2942 	int rc, bit;
2943 
2944 	if (!sata_scr_valid(link))
2945 		return -EOPNOTSUPP;
2946 
2947 	/* If SCR can be read, use it to determine the current SPD.
2948 	 * If not, use cached value in link->sata_spd.
2949 	 */
2950 	rc = sata_scr_read(link, SCR_STATUS, &sstatus);
2951 	if (rc == 0 && ata_sstatus_online(sstatus))
2952 		spd = (sstatus >> 4) & 0xf;
2953 	else
2954 		spd = link->sata_spd;
2955 
2956 	mask = link->sata_spd_limit;
2957 	if (mask <= 1)
2958 		return -EINVAL;
2959 
2960 	/* unconditionally mask off the highest bit */
2961 	bit = fls(mask) - 1;
2962 	mask &= ~(1 << bit);
2963 
2964 	/* Mask off all speeds higher than or equal to the current
2965 	 * one.  Force 1.5Gbps if current SPD is not available.
2966 	 */
2967 	if (spd > 1)
2968 		mask &= (1 << (spd - 1)) - 1;
2969 	else
2970 		mask &= 1;
2971 
2972 	/* were we already at the bottom? */
2973 	if (!mask)
2974 		return -EINVAL;
2975 
2976 	if (spd_limit) {
2977 		if (mask & ((1 << spd_limit) - 1))
2978 			mask &= (1 << spd_limit) - 1;
2979 		else {
2980 			bit = ffs(mask) - 1;
2981 			mask = 1 << bit;
2982 		}
2983 	}
2984 
2985 	link->sata_spd_limit = mask;
2986 
2987 	ata_link_warn(link, "limiting SATA link speed to %s\n",
2988 		      sata_spd_string(fls(mask)));
2989 
2990 	return 0;
2991 }
2992 
2993 static int __sata_set_spd_needed(struct ata_link *link, u32 *scontrol)
2994 {
2995 	struct ata_link *host_link = &link->ap->link;
2996 	u32 limit, target, spd;
2997 
2998 	limit = link->sata_spd_limit;
2999 
3000 	/* Don't configure downstream link faster than upstream link.
3001 	 * It doesn't speed up anything and some PMPs choke on such
3002 	 * configuration.
3003 	 */
3004 	if (!ata_is_host_link(link) && host_link->sata_spd)
3005 		limit &= (1 << host_link->sata_spd) - 1;
3006 
3007 	if (limit == UINT_MAX)
3008 		target = 0;
3009 	else
3010 		target = fls(limit);
3011 
3012 	spd = (*scontrol >> 4) & 0xf;
3013 	*scontrol = (*scontrol & ~0xf0) | ((target & 0xf) << 4);
3014 
3015 	return spd != target;
3016 }
3017 
3018 /**
3019  *	sata_set_spd_needed - is SATA spd configuration needed
3020  *	@link: Link in question
3021  *
3022  *	Test whether the spd limit in SControl matches
3023  *	@link->sata_spd_limit.  This function is used to determine
3024  *	whether hardreset is necessary to apply SATA spd
3025  *	configuration.
3026  *
3027  *	LOCKING:
3028  *	Inherited from caller.
3029  *
3030  *	RETURNS:
3031  *	1 if SATA spd configuration is needed, 0 otherwise.
3032  */
3033 static int sata_set_spd_needed(struct ata_link *link)
3034 {
3035 	u32 scontrol;
3036 
3037 	if (sata_scr_read(link, SCR_CONTROL, &scontrol))
3038 		return 1;
3039 
3040 	return __sata_set_spd_needed(link, &scontrol);
3041 }
3042 
3043 /**
3044  *	sata_set_spd - set SATA spd according to spd limit
3045  *	@link: Link to set SATA spd for
3046  *
3047  *	Set SATA spd of @link according to sata_spd_limit.
3048  *
3049  *	LOCKING:
3050  *	Inherited from caller.
3051  *
3052  *	RETURNS:
3053  *	0 if spd doesn't need to be changed, 1 if spd has been
3054  *	changed.  Negative errno if SCR registers are inaccessible.
3055  */
3056 int sata_set_spd(struct ata_link *link)
3057 {
3058 	u32 scontrol;
3059 	int rc;
3060 
3061 	if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3062 		return rc;
3063 
3064 	if (!__sata_set_spd_needed(link, &scontrol))
3065 		return 0;
3066 
3067 	if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
3068 		return rc;
3069 
3070 	return 1;
3071 }
3072 
3073 /*
3074  * This mode timing computation functionality is ported over from
3075  * drivers/ide/ide-timing.h and was originally written by Vojtech Pavlik
3076  */
3077 /*
3078  * PIO 0-4, MWDMA 0-2 and UDMA 0-6 timings (in nanoseconds).
3079  * These were taken from ATA/ATAPI-6 standard, rev 0a, except
3080  * for UDMA6, which is currently supported only by Maxtor drives.
3081  *
3082  * For PIO 5/6 MWDMA 3/4 see the CFA specification 3.0.
3083  */
3084 
3085 static const struct ata_timing ata_timing[] = {
3086 /*	{ XFER_PIO_SLOW, 120, 290, 240, 960, 290, 240, 0,  960,   0 }, */
3087 	{ XFER_PIO_0,     70, 290, 240, 600, 165, 150, 0,  600,   0 },
3088 	{ XFER_PIO_1,     50, 290,  93, 383, 125, 100, 0,  383,   0 },
3089 	{ XFER_PIO_2,     30, 290,  40, 330, 100,  90, 0,  240,   0 },
3090 	{ XFER_PIO_3,     30,  80,  70, 180,  80,  70, 0,  180,   0 },
3091 	{ XFER_PIO_4,     25,  70,  25, 120,  70,  25, 0,  120,   0 },
3092 	{ XFER_PIO_5,     15,  65,  25, 100,  65,  25, 0,  100,   0 },
3093 	{ XFER_PIO_6,     10,  55,  20,  80,  55,  20, 0,   80,   0 },
3094 
3095 	{ XFER_SW_DMA_0, 120,   0,   0,   0, 480, 480, 50, 960,   0 },
3096 	{ XFER_SW_DMA_1,  90,   0,   0,   0, 240, 240, 30, 480,   0 },
3097 	{ XFER_SW_DMA_2,  60,   0,   0,   0, 120, 120, 20, 240,   0 },
3098 
3099 	{ XFER_MW_DMA_0,  60,   0,   0,   0, 215, 215, 20, 480,   0 },
3100 	{ XFER_MW_DMA_1,  45,   0,   0,   0,  80,  50, 5,  150,   0 },
3101 	{ XFER_MW_DMA_2,  25,   0,   0,   0,  70,  25, 5,  120,   0 },
3102 	{ XFER_MW_DMA_3,  25,   0,   0,   0,  65,  25, 5,  100,   0 },
3103 	{ XFER_MW_DMA_4,  25,   0,   0,   0,  55,  20, 5,   80,   0 },
3104 
3105 /*	{ XFER_UDMA_SLOW,  0,   0,   0,   0,   0,   0, 0,    0, 150 }, */
3106 	{ XFER_UDMA_0,     0,   0,   0,   0,   0,   0, 0,    0, 120 },
3107 	{ XFER_UDMA_1,     0,   0,   0,   0,   0,   0, 0,    0,  80 },
3108 	{ XFER_UDMA_2,     0,   0,   0,   0,   0,   0, 0,    0,  60 },
3109 	{ XFER_UDMA_3,     0,   0,   0,   0,   0,   0, 0,    0,  45 },
3110 	{ XFER_UDMA_4,     0,   0,   0,   0,   0,   0, 0,    0,  30 },
3111 	{ XFER_UDMA_5,     0,   0,   0,   0,   0,   0, 0,    0,  20 },
3112 	{ XFER_UDMA_6,     0,   0,   0,   0,   0,   0, 0,    0,  15 },
3113 
3114 	{ 0xFF }
3115 };
3116 
3117 #define ENOUGH(v, unit)		(((v)-1)/(unit)+1)
3118 #define EZ(v, unit)		((v)?ENOUGH(v, unit):0)
3119 
3120 static void ata_timing_quantize(const struct ata_timing *t, struct ata_timing *q, int T, int UT)
3121 {
3122 	q->setup	= EZ(t->setup      * 1000,  T);
3123 	q->act8b	= EZ(t->act8b      * 1000,  T);
3124 	q->rec8b	= EZ(t->rec8b      * 1000,  T);
3125 	q->cyc8b	= EZ(t->cyc8b      * 1000,  T);
3126 	q->active	= EZ(t->active     * 1000,  T);
3127 	q->recover	= EZ(t->recover    * 1000,  T);
3128 	q->dmack_hold	= EZ(t->dmack_hold * 1000,  T);
3129 	q->cycle	= EZ(t->cycle      * 1000,  T);
3130 	q->udma		= EZ(t->udma       * 1000, UT);
3131 }
3132 
3133 void ata_timing_merge(const struct ata_timing *a, const struct ata_timing *b,
3134 		      struct ata_timing *m, unsigned int what)
3135 {
3136 	if (what & ATA_TIMING_SETUP  ) m->setup   = max(a->setup,   b->setup);
3137 	if (what & ATA_TIMING_ACT8B  ) m->act8b   = max(a->act8b,   b->act8b);
3138 	if (what & ATA_TIMING_REC8B  ) m->rec8b   = max(a->rec8b,   b->rec8b);
3139 	if (what & ATA_TIMING_CYC8B  ) m->cyc8b   = max(a->cyc8b,   b->cyc8b);
3140 	if (what & ATA_TIMING_ACTIVE ) m->active  = max(a->active,  b->active);
3141 	if (what & ATA_TIMING_RECOVER) m->recover = max(a->recover, b->recover);
3142 	if (what & ATA_TIMING_DMACK_HOLD) m->dmack_hold = max(a->dmack_hold, b->dmack_hold);
3143 	if (what & ATA_TIMING_CYCLE  ) m->cycle   = max(a->cycle,   b->cycle);
3144 	if (what & ATA_TIMING_UDMA   ) m->udma    = max(a->udma,    b->udma);
3145 }
3146 
3147 const struct ata_timing *ata_timing_find_mode(u8 xfer_mode)
3148 {
3149 	const struct ata_timing *t = ata_timing;
3150 
3151 	while (xfer_mode > t->mode)
3152 		t++;
3153 
3154 	if (xfer_mode == t->mode)
3155 		return t;
3156 
3157 	WARN_ONCE(true, "%s: unable to find timing for xfer_mode 0x%x\n",
3158 			__func__, xfer_mode);
3159 
3160 	return NULL;
3161 }
3162 
3163 int ata_timing_compute(struct ata_device *adev, unsigned short speed,
3164 		       struct ata_timing *t, int T, int UT)
3165 {
3166 	const u16 *id = adev->id;
3167 	const struct ata_timing *s;
3168 	struct ata_timing p;
3169 
3170 	/*
3171 	 * Find the mode.
3172 	 */
3173 
3174 	if (!(s = ata_timing_find_mode(speed)))
3175 		return -EINVAL;
3176 
3177 	memcpy(t, s, sizeof(*s));
3178 
3179 	/*
3180 	 * If the drive is an EIDE drive, it can tell us it needs extended
3181 	 * PIO/MW_DMA cycle timing.
3182 	 */
3183 
3184 	if (id[ATA_ID_FIELD_VALID] & 2) {	/* EIDE drive */
3185 		memset(&p, 0, sizeof(p));
3186 
3187 		if (speed >= XFER_PIO_0 && speed < XFER_SW_DMA_0) {
3188 			if (speed <= XFER_PIO_2)
3189 				p.cycle = p.cyc8b = id[ATA_ID_EIDE_PIO];
3190 			else if ((speed <= XFER_PIO_4) ||
3191 				 (speed == XFER_PIO_5 && !ata_id_is_cfa(id)))
3192 				p.cycle = p.cyc8b = id[ATA_ID_EIDE_PIO_IORDY];
3193 		} else if (speed >= XFER_MW_DMA_0 && speed <= XFER_MW_DMA_2)
3194 			p.cycle = id[ATA_ID_EIDE_DMA_MIN];
3195 
3196 		ata_timing_merge(&p, t, t, ATA_TIMING_CYCLE | ATA_TIMING_CYC8B);
3197 	}
3198 
3199 	/*
3200 	 * Convert the timing to bus clock counts.
3201 	 */
3202 
3203 	ata_timing_quantize(t, t, T, UT);
3204 
3205 	/*
3206 	 * Even in DMA/UDMA modes we still use PIO access for IDENTIFY,
3207 	 * S.M.A.R.T * and some other commands. We have to ensure that the
3208 	 * DMA cycle timing is slower/equal than the fastest PIO timing.
3209 	 */
3210 
3211 	if (speed > XFER_PIO_6) {
3212 		ata_timing_compute(adev, adev->pio_mode, &p, T, UT);
3213 		ata_timing_merge(&p, t, t, ATA_TIMING_ALL);
3214 	}
3215 
3216 	/*
3217 	 * Lengthen active & recovery time so that cycle time is correct.
3218 	 */
3219 
3220 	if (t->act8b + t->rec8b < t->cyc8b) {
3221 		t->act8b += (t->cyc8b - (t->act8b + t->rec8b)) / 2;
3222 		t->rec8b = t->cyc8b - t->act8b;
3223 	}
3224 
3225 	if (t->active + t->recover < t->cycle) {
3226 		t->active += (t->cycle - (t->active + t->recover)) / 2;
3227 		t->recover = t->cycle - t->active;
3228 	}
3229 
3230 	/* In a few cases quantisation may produce enough errors to
3231 	   leave t->cycle too low for the sum of active and recovery
3232 	   if so we must correct this */
3233 	if (t->active + t->recover > t->cycle)
3234 		t->cycle = t->active + t->recover;
3235 
3236 	return 0;
3237 }
3238 
3239 /**
3240  *	ata_timing_cycle2mode - find xfer mode for the specified cycle duration
3241  *	@xfer_shift: ATA_SHIFT_* value for transfer type to examine.
3242  *	@cycle: cycle duration in ns
3243  *
3244  *	Return matching xfer mode for @cycle.  The returned mode is of
3245  *	the transfer type specified by @xfer_shift.  If @cycle is too
3246  *	slow for @xfer_shift, 0xff is returned.  If @cycle is faster
3247  *	than the fastest known mode, the fasted mode is returned.
3248  *
3249  *	LOCKING:
3250  *	None.
3251  *
3252  *	RETURNS:
3253  *	Matching xfer_mode, 0xff if no match found.
3254  */
3255 u8 ata_timing_cycle2mode(unsigned int xfer_shift, int cycle)
3256 {
3257 	u8 base_mode = 0xff, last_mode = 0xff;
3258 	const struct ata_xfer_ent *ent;
3259 	const struct ata_timing *t;
3260 
3261 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
3262 		if (ent->shift == xfer_shift)
3263 			base_mode = ent->base;
3264 
3265 	for (t = ata_timing_find_mode(base_mode);
3266 	     t && ata_xfer_mode2shift(t->mode) == xfer_shift; t++) {
3267 		unsigned short this_cycle;
3268 
3269 		switch (xfer_shift) {
3270 		case ATA_SHIFT_PIO:
3271 		case ATA_SHIFT_MWDMA:
3272 			this_cycle = t->cycle;
3273 			break;
3274 		case ATA_SHIFT_UDMA:
3275 			this_cycle = t->udma;
3276 			break;
3277 		default:
3278 			return 0xff;
3279 		}
3280 
3281 		if (cycle > this_cycle)
3282 			break;
3283 
3284 		last_mode = t->mode;
3285 	}
3286 
3287 	return last_mode;
3288 }
3289 
3290 /**
3291  *	ata_down_xfermask_limit - adjust dev xfer masks downward
3292  *	@dev: Device to adjust xfer masks
3293  *	@sel: ATA_DNXFER_* selector
3294  *
3295  *	Adjust xfer masks of @dev downward.  Note that this function
3296  *	does not apply the change.  Invoking ata_set_mode() afterwards
3297  *	will apply the limit.
3298  *
3299  *	LOCKING:
3300  *	Inherited from caller.
3301  *
3302  *	RETURNS:
3303  *	0 on success, negative errno on failure
3304  */
3305 int ata_down_xfermask_limit(struct ata_device *dev, unsigned int sel)
3306 {
3307 	char buf[32];
3308 	unsigned long orig_mask, xfer_mask;
3309 	unsigned long pio_mask, mwdma_mask, udma_mask;
3310 	int quiet, highbit;
3311 
3312 	quiet = !!(sel & ATA_DNXFER_QUIET);
3313 	sel &= ~ATA_DNXFER_QUIET;
3314 
3315 	xfer_mask = orig_mask = ata_pack_xfermask(dev->pio_mask,
3316 						  dev->mwdma_mask,
3317 						  dev->udma_mask);
3318 	ata_unpack_xfermask(xfer_mask, &pio_mask, &mwdma_mask, &udma_mask);
3319 
3320 	switch (sel) {
3321 	case ATA_DNXFER_PIO:
3322 		highbit = fls(pio_mask) - 1;
3323 		pio_mask &= ~(1 << highbit);
3324 		break;
3325 
3326 	case ATA_DNXFER_DMA:
3327 		if (udma_mask) {
3328 			highbit = fls(udma_mask) - 1;
3329 			udma_mask &= ~(1 << highbit);
3330 			if (!udma_mask)
3331 				return -ENOENT;
3332 		} else if (mwdma_mask) {
3333 			highbit = fls(mwdma_mask) - 1;
3334 			mwdma_mask &= ~(1 << highbit);
3335 			if (!mwdma_mask)
3336 				return -ENOENT;
3337 		}
3338 		break;
3339 
3340 	case ATA_DNXFER_40C:
3341 		udma_mask &= ATA_UDMA_MASK_40C;
3342 		break;
3343 
3344 	case ATA_DNXFER_FORCE_PIO0:
3345 		pio_mask &= 1;
3346 	case ATA_DNXFER_FORCE_PIO:
3347 		mwdma_mask = 0;
3348 		udma_mask = 0;
3349 		break;
3350 
3351 	default:
3352 		BUG();
3353 	}
3354 
3355 	xfer_mask &= ata_pack_xfermask(pio_mask, mwdma_mask, udma_mask);
3356 
3357 	if (!(xfer_mask & ATA_MASK_PIO) || xfer_mask == orig_mask)
3358 		return -ENOENT;
3359 
3360 	if (!quiet) {
3361 		if (xfer_mask & (ATA_MASK_MWDMA | ATA_MASK_UDMA))
3362 			snprintf(buf, sizeof(buf), "%s:%s",
3363 				 ata_mode_string(xfer_mask),
3364 				 ata_mode_string(xfer_mask & ATA_MASK_PIO));
3365 		else
3366 			snprintf(buf, sizeof(buf), "%s",
3367 				 ata_mode_string(xfer_mask));
3368 
3369 		ata_dev_warn(dev, "limiting speed to %s\n", buf);
3370 	}
3371 
3372 	ata_unpack_xfermask(xfer_mask, &dev->pio_mask, &dev->mwdma_mask,
3373 			    &dev->udma_mask);
3374 
3375 	return 0;
3376 }
3377 
3378 static int ata_dev_set_mode(struct ata_device *dev)
3379 {
3380 	struct ata_port *ap = dev->link->ap;
3381 	struct ata_eh_context *ehc = &dev->link->eh_context;
3382 	const bool nosetxfer = dev->horkage & ATA_HORKAGE_NOSETXFER;
3383 	const char *dev_err_whine = "";
3384 	int ign_dev_err = 0;
3385 	unsigned int err_mask = 0;
3386 	int rc;
3387 
3388 	dev->flags &= ~ATA_DFLAG_PIO;
3389 	if (dev->xfer_shift == ATA_SHIFT_PIO)
3390 		dev->flags |= ATA_DFLAG_PIO;
3391 
3392 	if (nosetxfer && ap->flags & ATA_FLAG_SATA && ata_id_is_sata(dev->id))
3393 		dev_err_whine = " (SET_XFERMODE skipped)";
3394 	else {
3395 		if (nosetxfer)
3396 			ata_dev_warn(dev,
3397 				     "NOSETXFER but PATA detected - can't "
3398 				     "skip SETXFER, might malfunction\n");
3399 		err_mask = ata_dev_set_xfermode(dev);
3400 	}
3401 
3402 	if (err_mask & ~AC_ERR_DEV)
3403 		goto fail;
3404 
3405 	/* revalidate */
3406 	ehc->i.flags |= ATA_EHI_POST_SETMODE;
3407 	rc = ata_dev_revalidate(dev, ATA_DEV_UNKNOWN, 0);
3408 	ehc->i.flags &= ~ATA_EHI_POST_SETMODE;
3409 	if (rc)
3410 		return rc;
3411 
3412 	if (dev->xfer_shift == ATA_SHIFT_PIO) {
3413 		/* Old CFA may refuse this command, which is just fine */
3414 		if (ata_id_is_cfa(dev->id))
3415 			ign_dev_err = 1;
3416 		/* Catch several broken garbage emulations plus some pre
3417 		   ATA devices */
3418 		if (ata_id_major_version(dev->id) == 0 &&
3419 					dev->pio_mode <= XFER_PIO_2)
3420 			ign_dev_err = 1;
3421 		/* Some very old devices and some bad newer ones fail
3422 		   any kind of SET_XFERMODE request but support PIO0-2
3423 		   timings and no IORDY */
3424 		if (!ata_id_has_iordy(dev->id) && dev->pio_mode <= XFER_PIO_2)
3425 			ign_dev_err = 1;
3426 	}
3427 	/* Early MWDMA devices do DMA but don't allow DMA mode setting.
3428 	   Don't fail an MWDMA0 set IFF the device indicates it is in MWDMA0 */
3429 	if (dev->xfer_shift == ATA_SHIFT_MWDMA &&
3430 	    dev->dma_mode == XFER_MW_DMA_0 &&
3431 	    (dev->id[63] >> 8) & 1)
3432 		ign_dev_err = 1;
3433 
3434 	/* if the device is actually configured correctly, ignore dev err */
3435 	if (dev->xfer_mode == ata_xfer_mask2mode(ata_id_xfermask(dev->id)))
3436 		ign_dev_err = 1;
3437 
3438 	if (err_mask & AC_ERR_DEV) {
3439 		if (!ign_dev_err)
3440 			goto fail;
3441 		else
3442 			dev_err_whine = " (device error ignored)";
3443 	}
3444 
3445 	DPRINTK("xfer_shift=%u, xfer_mode=0x%x\n",
3446 		dev->xfer_shift, (int)dev->xfer_mode);
3447 
3448 	ata_dev_info(dev, "configured for %s%s\n",
3449 		     ata_mode_string(ata_xfer_mode2mask(dev->xfer_mode)),
3450 		     dev_err_whine);
3451 
3452 	return 0;
3453 
3454  fail:
3455 	ata_dev_err(dev, "failed to set xfermode (err_mask=0x%x)\n", err_mask);
3456 	return -EIO;
3457 }
3458 
3459 /**
3460  *	ata_do_set_mode - Program timings and issue SET FEATURES - XFER
3461  *	@link: link on which timings will be programmed
3462  *	@r_failed_dev: out parameter for failed device
3463  *
3464  *	Standard implementation of the function used to tune and set
3465  *	ATA device disk transfer mode (PIO3, UDMA6, etc.).  If
3466  *	ata_dev_set_mode() fails, pointer to the failing device is
3467  *	returned in @r_failed_dev.
3468  *
3469  *	LOCKING:
3470  *	PCI/etc. bus probe sem.
3471  *
3472  *	RETURNS:
3473  *	0 on success, negative errno otherwise
3474  */
3475 
3476 int ata_do_set_mode(struct ata_link *link, struct ata_device **r_failed_dev)
3477 {
3478 	struct ata_port *ap = link->ap;
3479 	struct ata_device *dev;
3480 	int rc = 0, used_dma = 0, found = 0;
3481 
3482 	/* step 1: calculate xfer_mask */
3483 	ata_for_each_dev(dev, link, ENABLED) {
3484 		unsigned long pio_mask, dma_mask;
3485 		unsigned int mode_mask;
3486 
3487 		mode_mask = ATA_DMA_MASK_ATA;
3488 		if (dev->class == ATA_DEV_ATAPI)
3489 			mode_mask = ATA_DMA_MASK_ATAPI;
3490 		else if (ata_id_is_cfa(dev->id))
3491 			mode_mask = ATA_DMA_MASK_CFA;
3492 
3493 		ata_dev_xfermask(dev);
3494 		ata_force_xfermask(dev);
3495 
3496 		pio_mask = ata_pack_xfermask(dev->pio_mask, 0, 0);
3497 
3498 		if (libata_dma_mask & mode_mask)
3499 			dma_mask = ata_pack_xfermask(0, dev->mwdma_mask,
3500 						     dev->udma_mask);
3501 		else
3502 			dma_mask = 0;
3503 
3504 		dev->pio_mode = ata_xfer_mask2mode(pio_mask);
3505 		dev->dma_mode = ata_xfer_mask2mode(dma_mask);
3506 
3507 		found = 1;
3508 		if (ata_dma_enabled(dev))
3509 			used_dma = 1;
3510 	}
3511 	if (!found)
3512 		goto out;
3513 
3514 	/* step 2: always set host PIO timings */
3515 	ata_for_each_dev(dev, link, ENABLED) {
3516 		if (dev->pio_mode == 0xff) {
3517 			ata_dev_warn(dev, "no PIO support\n");
3518 			rc = -EINVAL;
3519 			goto out;
3520 		}
3521 
3522 		dev->xfer_mode = dev->pio_mode;
3523 		dev->xfer_shift = ATA_SHIFT_PIO;
3524 		if (ap->ops->set_piomode)
3525 			ap->ops->set_piomode(ap, dev);
3526 	}
3527 
3528 	/* step 3: set host DMA timings */
3529 	ata_for_each_dev(dev, link, ENABLED) {
3530 		if (!ata_dma_enabled(dev))
3531 			continue;
3532 
3533 		dev->xfer_mode = dev->dma_mode;
3534 		dev->xfer_shift = ata_xfer_mode2shift(dev->dma_mode);
3535 		if (ap->ops->set_dmamode)
3536 			ap->ops->set_dmamode(ap, dev);
3537 	}
3538 
3539 	/* step 4: update devices' xfer mode */
3540 	ata_for_each_dev(dev, link, ENABLED) {
3541 		rc = ata_dev_set_mode(dev);
3542 		if (rc)
3543 			goto out;
3544 	}
3545 
3546 	/* Record simplex status. If we selected DMA then the other
3547 	 * host channels are not permitted to do so.
3548 	 */
3549 	if (used_dma && (ap->host->flags & ATA_HOST_SIMPLEX))
3550 		ap->host->simplex_claimed = ap;
3551 
3552  out:
3553 	if (rc)
3554 		*r_failed_dev = dev;
3555 	return rc;
3556 }
3557 
3558 /**
3559  *	ata_wait_ready - wait for link to become ready
3560  *	@link: link to be waited on
3561  *	@deadline: deadline jiffies for the operation
3562  *	@check_ready: callback to check link readiness
3563  *
3564  *	Wait for @link to become ready.  @check_ready should return
3565  *	positive number if @link is ready, 0 if it isn't, -ENODEV if
3566  *	link doesn't seem to be occupied, other errno for other error
3567  *	conditions.
3568  *
3569  *	Transient -ENODEV conditions are allowed for
3570  *	ATA_TMOUT_FF_WAIT.
3571  *
3572  *	LOCKING:
3573  *	EH context.
3574  *
3575  *	RETURNS:
3576  *	0 if @link is ready before @deadline; otherwise, -errno.
3577  */
3578 int ata_wait_ready(struct ata_link *link, unsigned long deadline,
3579 		   int (*check_ready)(struct ata_link *link))
3580 {
3581 	unsigned long start = jiffies;
3582 	unsigned long nodev_deadline;
3583 	int warned = 0;
3584 
3585 	/* choose which 0xff timeout to use, read comment in libata.h */
3586 	if (link->ap->host->flags & ATA_HOST_PARALLEL_SCAN)
3587 		nodev_deadline = ata_deadline(start, ATA_TMOUT_FF_WAIT_LONG);
3588 	else
3589 		nodev_deadline = ata_deadline(start, ATA_TMOUT_FF_WAIT);
3590 
3591 	/* Slave readiness can't be tested separately from master.  On
3592 	 * M/S emulation configuration, this function should be called
3593 	 * only on the master and it will handle both master and slave.
3594 	 */
3595 	WARN_ON(link == link->ap->slave_link);
3596 
3597 	if (time_after(nodev_deadline, deadline))
3598 		nodev_deadline = deadline;
3599 
3600 	while (1) {
3601 		unsigned long now = jiffies;
3602 		int ready, tmp;
3603 
3604 		ready = tmp = check_ready(link);
3605 		if (ready > 0)
3606 			return 0;
3607 
3608 		/*
3609 		 * -ENODEV could be transient.  Ignore -ENODEV if link
3610 		 * is online.  Also, some SATA devices take a long
3611 		 * time to clear 0xff after reset.  Wait for
3612 		 * ATA_TMOUT_FF_WAIT[_LONG] on -ENODEV if link isn't
3613 		 * offline.
3614 		 *
3615 		 * Note that some PATA controllers (pata_ali) explode
3616 		 * if status register is read more than once when
3617 		 * there's no device attached.
3618 		 */
3619 		if (ready == -ENODEV) {
3620 			if (ata_link_online(link))
3621 				ready = 0;
3622 			else if ((link->ap->flags & ATA_FLAG_SATA) &&
3623 				 !ata_link_offline(link) &&
3624 				 time_before(now, nodev_deadline))
3625 				ready = 0;
3626 		}
3627 
3628 		if (ready)
3629 			return ready;
3630 		if (time_after(now, deadline))
3631 			return -EBUSY;
3632 
3633 		if (!warned && time_after(now, start + 5 * HZ) &&
3634 		    (deadline - now > 3 * HZ)) {
3635 			ata_link_warn(link,
3636 				"link is slow to respond, please be patient "
3637 				"(ready=%d)\n", tmp);
3638 			warned = 1;
3639 		}
3640 
3641 		ata_msleep(link->ap, 50);
3642 	}
3643 }
3644 
3645 /**
3646  *	ata_wait_after_reset - wait for link to become ready after reset
3647  *	@link: link to be waited on
3648  *	@deadline: deadline jiffies for the operation
3649  *	@check_ready: callback to check link readiness
3650  *
3651  *	Wait for @link to become ready after reset.
3652  *
3653  *	LOCKING:
3654  *	EH context.
3655  *
3656  *	RETURNS:
3657  *	0 if @link is ready before @deadline; otherwise, -errno.
3658  */
3659 int ata_wait_after_reset(struct ata_link *link, unsigned long deadline,
3660 				int (*check_ready)(struct ata_link *link))
3661 {
3662 	ata_msleep(link->ap, ATA_WAIT_AFTER_RESET);
3663 
3664 	return ata_wait_ready(link, deadline, check_ready);
3665 }
3666 
3667 /**
3668  *	sata_link_debounce - debounce SATA phy status
3669  *	@link: ATA link to debounce SATA phy status for
3670  *	@params: timing parameters { interval, duration, timeout } in msec
3671  *	@deadline: deadline jiffies for the operation
3672  *
3673  *	Make sure SStatus of @link reaches stable state, determined by
3674  *	holding the same value where DET is not 1 for @duration polled
3675  *	every @interval, before @timeout.  Timeout constraints the
3676  *	beginning of the stable state.  Because DET gets stuck at 1 on
3677  *	some controllers after hot unplugging, this functions waits
3678  *	until timeout then returns 0 if DET is stable at 1.
3679  *
3680  *	@timeout is further limited by @deadline.  The sooner of the
3681  *	two is used.
3682  *
3683  *	LOCKING:
3684  *	Kernel thread context (may sleep)
3685  *
3686  *	RETURNS:
3687  *	0 on success, -errno on failure.
3688  */
3689 int sata_link_debounce(struct ata_link *link, const unsigned long *params,
3690 		       unsigned long deadline)
3691 {
3692 	unsigned long interval = params[0];
3693 	unsigned long duration = params[1];
3694 	unsigned long last_jiffies, t;
3695 	u32 last, cur;
3696 	int rc;
3697 
3698 	t = ata_deadline(jiffies, params[2]);
3699 	if (time_before(t, deadline))
3700 		deadline = t;
3701 
3702 	if ((rc = sata_scr_read(link, SCR_STATUS, &cur)))
3703 		return rc;
3704 	cur &= 0xf;
3705 
3706 	last = cur;
3707 	last_jiffies = jiffies;
3708 
3709 	while (1) {
3710 		ata_msleep(link->ap, interval);
3711 		if ((rc = sata_scr_read(link, SCR_STATUS, &cur)))
3712 			return rc;
3713 		cur &= 0xf;
3714 
3715 		/* DET stable? */
3716 		if (cur == last) {
3717 			if (cur == 1 && time_before(jiffies, deadline))
3718 				continue;
3719 			if (time_after(jiffies,
3720 				       ata_deadline(last_jiffies, duration)))
3721 				return 0;
3722 			continue;
3723 		}
3724 
3725 		/* unstable, start over */
3726 		last = cur;
3727 		last_jiffies = jiffies;
3728 
3729 		/* Check deadline.  If debouncing failed, return
3730 		 * -EPIPE to tell upper layer to lower link speed.
3731 		 */
3732 		if (time_after(jiffies, deadline))
3733 			return -EPIPE;
3734 	}
3735 }
3736 
3737 /**
3738  *	sata_link_resume - resume SATA link
3739  *	@link: ATA link to resume SATA
3740  *	@params: timing parameters { interval, duration, timeout } in msec
3741  *	@deadline: deadline jiffies for the operation
3742  *
3743  *	Resume SATA phy @link and debounce it.
3744  *
3745  *	LOCKING:
3746  *	Kernel thread context (may sleep)
3747  *
3748  *	RETURNS:
3749  *	0 on success, -errno on failure.
3750  */
3751 int sata_link_resume(struct ata_link *link, const unsigned long *params,
3752 		     unsigned long deadline)
3753 {
3754 	int tries = ATA_LINK_RESUME_TRIES;
3755 	u32 scontrol, serror;
3756 	int rc;
3757 
3758 	if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3759 		return rc;
3760 
3761 	/*
3762 	 * Writes to SControl sometimes get ignored under certain
3763 	 * controllers (ata_piix SIDPR).  Make sure DET actually is
3764 	 * cleared.
3765 	 */
3766 	do {
3767 		scontrol = (scontrol & 0x0f0) | 0x300;
3768 		if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
3769 			return rc;
3770 		/*
3771 		 * Some PHYs react badly if SStatus is pounded
3772 		 * immediately after resuming.  Delay 200ms before
3773 		 * debouncing.
3774 		 */
3775 		if (!(link->flags & ATA_LFLAG_NO_DB_DELAY))
3776 			ata_msleep(link->ap, 200);
3777 
3778 		/* is SControl restored correctly? */
3779 		if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3780 			return rc;
3781 	} while ((scontrol & 0xf0f) != 0x300 && --tries);
3782 
3783 	if ((scontrol & 0xf0f) != 0x300) {
3784 		ata_link_warn(link, "failed to resume link (SControl %X)\n",
3785 			     scontrol);
3786 		return 0;
3787 	}
3788 
3789 	if (tries < ATA_LINK_RESUME_TRIES)
3790 		ata_link_warn(link, "link resume succeeded after %d retries\n",
3791 			      ATA_LINK_RESUME_TRIES - tries);
3792 
3793 	if ((rc = sata_link_debounce(link, params, deadline)))
3794 		return rc;
3795 
3796 	/* clear SError, some PHYs require this even for SRST to work */
3797 	if (!(rc = sata_scr_read(link, SCR_ERROR, &serror)))
3798 		rc = sata_scr_write(link, SCR_ERROR, serror);
3799 
3800 	return rc != -EINVAL ? rc : 0;
3801 }
3802 
3803 /**
3804  *	sata_link_scr_lpm - manipulate SControl IPM and SPM fields
3805  *	@link: ATA link to manipulate SControl for
3806  *	@policy: LPM policy to configure
3807  *	@spm_wakeup: initiate LPM transition to active state
3808  *
3809  *	Manipulate the IPM field of the SControl register of @link
3810  *	according to @policy.  If @policy is ATA_LPM_MAX_POWER and
3811  *	@spm_wakeup is %true, the SPM field is manipulated to wake up
3812  *	the link.  This function also clears PHYRDY_CHG before
3813  *	returning.
3814  *
3815  *	LOCKING:
3816  *	EH context.
3817  *
3818  *	RETURNS:
3819  *	0 on success, -errno otherwise.
3820  */
3821 int sata_link_scr_lpm(struct ata_link *link, enum ata_lpm_policy policy,
3822 		      bool spm_wakeup)
3823 {
3824 	struct ata_eh_context *ehc = &link->eh_context;
3825 	bool woken_up = false;
3826 	u32 scontrol;
3827 	int rc;
3828 
3829 	rc = sata_scr_read(link, SCR_CONTROL, &scontrol);
3830 	if (rc)
3831 		return rc;
3832 
3833 	switch (policy) {
3834 	case ATA_LPM_MAX_POWER:
3835 		/* disable all LPM transitions */
3836 		scontrol |= (0x7 << 8);
3837 		/* initiate transition to active state */
3838 		if (spm_wakeup) {
3839 			scontrol |= (0x4 << 12);
3840 			woken_up = true;
3841 		}
3842 		break;
3843 	case ATA_LPM_MED_POWER:
3844 		/* allow LPM to PARTIAL */
3845 		scontrol &= ~(0x1 << 8);
3846 		scontrol |= (0x6 << 8);
3847 		break;
3848 	case ATA_LPM_MIN_POWER:
3849 		if (ata_link_nr_enabled(link) > 0)
3850 			/* no restrictions on LPM transitions */
3851 			scontrol &= ~(0x7 << 8);
3852 		else {
3853 			/* empty port, power off */
3854 			scontrol &= ~0xf;
3855 			scontrol |= (0x1 << 2);
3856 		}
3857 		break;
3858 	default:
3859 		WARN_ON(1);
3860 	}
3861 
3862 	rc = sata_scr_write(link, SCR_CONTROL, scontrol);
3863 	if (rc)
3864 		return rc;
3865 
3866 	/* give the link time to transit out of LPM state */
3867 	if (woken_up)
3868 		msleep(10);
3869 
3870 	/* clear PHYRDY_CHG from SError */
3871 	ehc->i.serror &= ~SERR_PHYRDY_CHG;
3872 	return sata_scr_write(link, SCR_ERROR, SERR_PHYRDY_CHG);
3873 }
3874 
3875 /**
3876  *	ata_std_prereset - prepare for reset
3877  *	@link: ATA link to be reset
3878  *	@deadline: deadline jiffies for the operation
3879  *
3880  *	@link is about to be reset.  Initialize it.  Failure from
3881  *	prereset makes libata abort whole reset sequence and give up
3882  *	that port, so prereset should be best-effort.  It does its
3883  *	best to prepare for reset sequence but if things go wrong, it
3884  *	should just whine, not fail.
3885  *
3886  *	LOCKING:
3887  *	Kernel thread context (may sleep)
3888  *
3889  *	RETURNS:
3890  *	0 on success, -errno otherwise.
3891  */
3892 int ata_std_prereset(struct ata_link *link, unsigned long deadline)
3893 {
3894 	struct ata_port *ap = link->ap;
3895 	struct ata_eh_context *ehc = &link->eh_context;
3896 	const unsigned long *timing = sata_ehc_deb_timing(ehc);
3897 	int rc;
3898 
3899 	/* if we're about to do hardreset, nothing more to do */
3900 	if (ehc->i.action & ATA_EH_HARDRESET)
3901 		return 0;
3902 
3903 	/* if SATA, resume link */
3904 	if (ap->flags & ATA_FLAG_SATA) {
3905 		rc = sata_link_resume(link, timing, deadline);
3906 		/* whine about phy resume failure but proceed */
3907 		if (rc && rc != -EOPNOTSUPP)
3908 			ata_link_warn(link,
3909 				      "failed to resume link for reset (errno=%d)\n",
3910 				      rc);
3911 	}
3912 
3913 	/* no point in trying softreset on offline link */
3914 	if (ata_phys_link_offline(link))
3915 		ehc->i.action &= ~ATA_EH_SOFTRESET;
3916 
3917 	return 0;
3918 }
3919 
3920 /**
3921  *	sata_link_hardreset - reset link via SATA phy reset
3922  *	@link: link to reset
3923  *	@timing: timing parameters { interval, duration, timeout } in msec
3924  *	@deadline: deadline jiffies for the operation
3925  *	@online: optional out parameter indicating link onlineness
3926  *	@check_ready: optional callback to check link readiness
3927  *
3928  *	SATA phy-reset @link using DET bits of SControl register.
3929  *	After hardreset, link readiness is waited upon using
3930  *	ata_wait_ready() if @check_ready is specified.  LLDs are
3931  *	allowed to not specify @check_ready and wait itself after this
3932  *	function returns.  Device classification is LLD's
3933  *	responsibility.
3934  *
3935  *	*@online is set to one iff reset succeeded and @link is online
3936  *	after reset.
3937  *
3938  *	LOCKING:
3939  *	Kernel thread context (may sleep)
3940  *
3941  *	RETURNS:
3942  *	0 on success, -errno otherwise.
3943  */
3944 int sata_link_hardreset(struct ata_link *link, const unsigned long *timing,
3945 			unsigned long deadline,
3946 			bool *online, int (*check_ready)(struct ata_link *))
3947 {
3948 	u32 scontrol;
3949 	int rc;
3950 
3951 	DPRINTK("ENTER\n");
3952 
3953 	if (online)
3954 		*online = false;
3955 
3956 	if (sata_set_spd_needed(link)) {
3957 		/* SATA spec says nothing about how to reconfigure
3958 		 * spd.  To be on the safe side, turn off phy during
3959 		 * reconfiguration.  This works for at least ICH7 AHCI
3960 		 * and Sil3124.
3961 		 */
3962 		if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3963 			goto out;
3964 
3965 		scontrol = (scontrol & 0x0f0) | 0x304;
3966 
3967 		if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
3968 			goto out;
3969 
3970 		sata_set_spd(link);
3971 	}
3972 
3973 	/* issue phy wake/reset */
3974 	if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3975 		goto out;
3976 
3977 	scontrol = (scontrol & 0x0f0) | 0x301;
3978 
3979 	if ((rc = sata_scr_write_flush(link, SCR_CONTROL, scontrol)))
3980 		goto out;
3981 
3982 	/* Couldn't find anything in SATA I/II specs, but AHCI-1.1
3983 	 * 10.4.2 says at least 1 ms.
3984 	 */
3985 	ata_msleep(link->ap, 1);
3986 
3987 	/* bring link back */
3988 	rc = sata_link_resume(link, timing, deadline);
3989 	if (rc)
3990 		goto out;
3991 	/* if link is offline nothing more to do */
3992 	if (ata_phys_link_offline(link))
3993 		goto out;
3994 
3995 	/* Link is online.  From this point, -ENODEV too is an error. */
3996 	if (online)
3997 		*online = true;
3998 
3999 	if (sata_pmp_supported(link->ap) && ata_is_host_link(link)) {
4000 		/* If PMP is supported, we have to do follow-up SRST.
4001 		 * Some PMPs don't send D2H Reg FIS after hardreset if
4002 		 * the first port is empty.  Wait only for
4003 		 * ATA_TMOUT_PMP_SRST_WAIT.
4004 		 */
4005 		if (check_ready) {
4006 			unsigned long pmp_deadline;
4007 
4008 			pmp_deadline = ata_deadline(jiffies,
4009 						    ATA_TMOUT_PMP_SRST_WAIT);
4010 			if (time_after(pmp_deadline, deadline))
4011 				pmp_deadline = deadline;
4012 			ata_wait_ready(link, pmp_deadline, check_ready);
4013 		}
4014 		rc = -EAGAIN;
4015 		goto out;
4016 	}
4017 
4018 	rc = 0;
4019 	if (check_ready)
4020 		rc = ata_wait_ready(link, deadline, check_ready);
4021  out:
4022 	if (rc && rc != -EAGAIN) {
4023 		/* online is set iff link is online && reset succeeded */
4024 		if (online)
4025 			*online = false;
4026 		ata_link_err(link, "COMRESET failed (errno=%d)\n", rc);
4027 	}
4028 	DPRINTK("EXIT, rc=%d\n", rc);
4029 	return rc;
4030 }
4031 
4032 /**
4033  *	sata_std_hardreset - COMRESET w/o waiting or classification
4034  *	@link: link to reset
4035  *	@class: resulting class of attached device
4036  *	@deadline: deadline jiffies for the operation
4037  *
4038  *	Standard SATA COMRESET w/o waiting or classification.
4039  *
4040  *	LOCKING:
4041  *	Kernel thread context (may sleep)
4042  *
4043  *	RETURNS:
4044  *	0 if link offline, -EAGAIN if link online, -errno on errors.
4045  */
4046 int sata_std_hardreset(struct ata_link *link, unsigned int *class,
4047 		       unsigned long deadline)
4048 {
4049 	const unsigned long *timing = sata_ehc_deb_timing(&link->eh_context);
4050 	bool online;
4051 	int rc;
4052 
4053 	/* do hardreset */
4054 	rc = sata_link_hardreset(link, timing, deadline, &online, NULL);
4055 	return online ? -EAGAIN : rc;
4056 }
4057 
4058 /**
4059  *	ata_std_postreset - standard postreset callback
4060  *	@link: the target ata_link
4061  *	@classes: classes of attached devices
4062  *
4063  *	This function is invoked after a successful reset.  Note that
4064  *	the device might have been reset more than once using
4065  *	different reset methods before postreset is invoked.
4066  *
4067  *	LOCKING:
4068  *	Kernel thread context (may sleep)
4069  */
4070 void ata_std_postreset(struct ata_link *link, unsigned int *classes)
4071 {
4072 	u32 serror;
4073 
4074 	DPRINTK("ENTER\n");
4075 
4076 	/* reset complete, clear SError */
4077 	if (!sata_scr_read(link, SCR_ERROR, &serror))
4078 		sata_scr_write(link, SCR_ERROR, serror);
4079 
4080 	/* print link status */
4081 	sata_print_link_status(link);
4082 
4083 	DPRINTK("EXIT\n");
4084 }
4085 
4086 /**
4087  *	ata_dev_same_device - Determine whether new ID matches configured device
4088  *	@dev: device to compare against
4089  *	@new_class: class of the new device
4090  *	@new_id: IDENTIFY page of the new device
4091  *
4092  *	Compare @new_class and @new_id against @dev and determine
4093  *	whether @dev is the device indicated by @new_class and
4094  *	@new_id.
4095  *
4096  *	LOCKING:
4097  *	None.
4098  *
4099  *	RETURNS:
4100  *	1 if @dev matches @new_class and @new_id, 0 otherwise.
4101  */
4102 static int ata_dev_same_device(struct ata_device *dev, unsigned int new_class,
4103 			       const u16 *new_id)
4104 {
4105 	const u16 *old_id = dev->id;
4106 	unsigned char model[2][ATA_ID_PROD_LEN + 1];
4107 	unsigned char serial[2][ATA_ID_SERNO_LEN + 1];
4108 
4109 	if (dev->class != new_class) {
4110 		ata_dev_info(dev, "class mismatch %d != %d\n",
4111 			     dev->class, new_class);
4112 		return 0;
4113 	}
4114 
4115 	ata_id_c_string(old_id, model[0], ATA_ID_PROD, sizeof(model[0]));
4116 	ata_id_c_string(new_id, model[1], ATA_ID_PROD, sizeof(model[1]));
4117 	ata_id_c_string(old_id, serial[0], ATA_ID_SERNO, sizeof(serial[0]));
4118 	ata_id_c_string(new_id, serial[1], ATA_ID_SERNO, sizeof(serial[1]));
4119 
4120 	if (strcmp(model[0], model[1])) {
4121 		ata_dev_info(dev, "model number mismatch '%s' != '%s'\n",
4122 			     model[0], model[1]);
4123 		return 0;
4124 	}
4125 
4126 	if (strcmp(serial[0], serial[1])) {
4127 		ata_dev_info(dev, "serial number mismatch '%s' != '%s'\n",
4128 			     serial[0], serial[1]);
4129 		return 0;
4130 	}
4131 
4132 	return 1;
4133 }
4134 
4135 /**
4136  *	ata_dev_reread_id - Re-read IDENTIFY data
4137  *	@dev: target ATA device
4138  *	@readid_flags: read ID flags
4139  *
4140  *	Re-read IDENTIFY page and make sure @dev is still attached to
4141  *	the port.
4142  *
4143  *	LOCKING:
4144  *	Kernel thread context (may sleep)
4145  *
4146  *	RETURNS:
4147  *	0 on success, negative errno otherwise
4148  */
4149 int ata_dev_reread_id(struct ata_device *dev, unsigned int readid_flags)
4150 {
4151 	unsigned int class = dev->class;
4152 	u16 *id = (void *)dev->link->ap->sector_buf;
4153 	int rc;
4154 
4155 	/* read ID data */
4156 	rc = ata_dev_read_id(dev, &class, readid_flags, id);
4157 	if (rc)
4158 		return rc;
4159 
4160 	/* is the device still there? */
4161 	if (!ata_dev_same_device(dev, class, id))
4162 		return -ENODEV;
4163 
4164 	memcpy(dev->id, id, sizeof(id[0]) * ATA_ID_WORDS);
4165 	return 0;
4166 }
4167 
4168 /**
4169  *	ata_dev_revalidate - Revalidate ATA device
4170  *	@dev: device to revalidate
4171  *	@new_class: new class code
4172  *	@readid_flags: read ID flags
4173  *
4174  *	Re-read IDENTIFY page, make sure @dev is still attached to the
4175  *	port and reconfigure it according to the new IDENTIFY page.
4176  *
4177  *	LOCKING:
4178  *	Kernel thread context (may sleep)
4179  *
4180  *	RETURNS:
4181  *	0 on success, negative errno otherwise
4182  */
4183 int ata_dev_revalidate(struct ata_device *dev, unsigned int new_class,
4184 		       unsigned int readid_flags)
4185 {
4186 	u64 n_sectors = dev->n_sectors;
4187 	u64 n_native_sectors = dev->n_native_sectors;
4188 	int rc;
4189 
4190 	if (!ata_dev_enabled(dev))
4191 		return -ENODEV;
4192 
4193 	/* fail early if !ATA && !ATAPI to avoid issuing [P]IDENTIFY to PMP */
4194 	if (ata_class_enabled(new_class) &&
4195 	    new_class != ATA_DEV_ATA &&
4196 	    new_class != ATA_DEV_ATAPI &&
4197 	    new_class != ATA_DEV_ZAC &&
4198 	    new_class != ATA_DEV_SEMB) {
4199 		ata_dev_info(dev, "class mismatch %u != %u\n",
4200 			     dev->class, new_class);
4201 		rc = -ENODEV;
4202 		goto fail;
4203 	}
4204 
4205 	/* re-read ID */
4206 	rc = ata_dev_reread_id(dev, readid_flags);
4207 	if (rc)
4208 		goto fail;
4209 
4210 	/* configure device according to the new ID */
4211 	rc = ata_dev_configure(dev);
4212 	if (rc)
4213 		goto fail;
4214 
4215 	/* verify n_sectors hasn't changed */
4216 	if (dev->class != ATA_DEV_ATA || !n_sectors ||
4217 	    dev->n_sectors == n_sectors)
4218 		return 0;
4219 
4220 	/* n_sectors has changed */
4221 	ata_dev_warn(dev, "n_sectors mismatch %llu != %llu\n",
4222 		     (unsigned long long)n_sectors,
4223 		     (unsigned long long)dev->n_sectors);
4224 
4225 	/*
4226 	 * Something could have caused HPA to be unlocked
4227 	 * involuntarily.  If n_native_sectors hasn't changed and the
4228 	 * new size matches it, keep the device.
4229 	 */
4230 	if (dev->n_native_sectors == n_native_sectors &&
4231 	    dev->n_sectors > n_sectors && dev->n_sectors == n_native_sectors) {
4232 		ata_dev_warn(dev,
4233 			     "new n_sectors matches native, probably "
4234 			     "late HPA unlock, n_sectors updated\n");
4235 		/* use the larger n_sectors */
4236 		return 0;
4237 	}
4238 
4239 	/*
4240 	 * Some BIOSes boot w/o HPA but resume w/ HPA locked.  Try
4241 	 * unlocking HPA in those cases.
4242 	 *
4243 	 * https://bugzilla.kernel.org/show_bug.cgi?id=15396
4244 	 */
4245 	if (dev->n_native_sectors == n_native_sectors &&
4246 	    dev->n_sectors < n_sectors && n_sectors == n_native_sectors &&
4247 	    !(dev->horkage & ATA_HORKAGE_BROKEN_HPA)) {
4248 		ata_dev_warn(dev,
4249 			     "old n_sectors matches native, probably "
4250 			     "late HPA lock, will try to unlock HPA\n");
4251 		/* try unlocking HPA */
4252 		dev->flags |= ATA_DFLAG_UNLOCK_HPA;
4253 		rc = -EIO;
4254 	} else
4255 		rc = -ENODEV;
4256 
4257 	/* restore original n_[native_]sectors and fail */
4258 	dev->n_native_sectors = n_native_sectors;
4259 	dev->n_sectors = n_sectors;
4260  fail:
4261 	ata_dev_err(dev, "revalidation failed (errno=%d)\n", rc);
4262 	return rc;
4263 }
4264 
4265 struct ata_blacklist_entry {
4266 	const char *model_num;
4267 	const char *model_rev;
4268 	unsigned long horkage;
4269 };
4270 
4271 static const struct ata_blacklist_entry ata_device_blacklist [] = {
4272 	/* Devices with DMA related problems under Linux */
4273 	{ "WDC AC11000H",	NULL,		ATA_HORKAGE_NODMA },
4274 	{ "WDC AC22100H",	NULL,		ATA_HORKAGE_NODMA },
4275 	{ "WDC AC32500H",	NULL,		ATA_HORKAGE_NODMA },
4276 	{ "WDC AC33100H",	NULL,		ATA_HORKAGE_NODMA },
4277 	{ "WDC AC31600H",	NULL,		ATA_HORKAGE_NODMA },
4278 	{ "WDC AC32100H",	"24.09P07",	ATA_HORKAGE_NODMA },
4279 	{ "WDC AC23200L",	"21.10N21",	ATA_HORKAGE_NODMA },
4280 	{ "Compaq CRD-8241B", 	NULL,		ATA_HORKAGE_NODMA },
4281 	{ "CRD-8400B",		NULL, 		ATA_HORKAGE_NODMA },
4282 	{ "CRD-848[02]B",	NULL,		ATA_HORKAGE_NODMA },
4283 	{ "CRD-84",		NULL,		ATA_HORKAGE_NODMA },
4284 	{ "SanDisk SDP3B",	NULL,		ATA_HORKAGE_NODMA },
4285 	{ "SanDisk SDP3B-64",	NULL,		ATA_HORKAGE_NODMA },
4286 	{ "SANYO CD-ROM CRD",	NULL,		ATA_HORKAGE_NODMA },
4287 	{ "HITACHI CDR-8",	NULL,		ATA_HORKAGE_NODMA },
4288 	{ "HITACHI CDR-8[34]35",NULL,		ATA_HORKAGE_NODMA },
4289 	{ "Toshiba CD-ROM XM-6202B", NULL,	ATA_HORKAGE_NODMA },
4290 	{ "TOSHIBA CD-ROM XM-1702BC", NULL,	ATA_HORKAGE_NODMA },
4291 	{ "CD-532E-A", 		NULL,		ATA_HORKAGE_NODMA },
4292 	{ "E-IDE CD-ROM CR-840",NULL,		ATA_HORKAGE_NODMA },
4293 	{ "CD-ROM Drive/F5A",	NULL,		ATA_HORKAGE_NODMA },
4294 	{ "WPI CDD-820", 	NULL,		ATA_HORKAGE_NODMA },
4295 	{ "SAMSUNG CD-ROM SC-148C", NULL,	ATA_HORKAGE_NODMA },
4296 	{ "SAMSUNG CD-ROM SC",	NULL,		ATA_HORKAGE_NODMA },
4297 	{ "ATAPI CD-ROM DRIVE 40X MAXIMUM",NULL,ATA_HORKAGE_NODMA },
4298 	{ "_NEC DV5800A", 	NULL,		ATA_HORKAGE_NODMA },
4299 	{ "SAMSUNG CD-ROM SN-124", "N001",	ATA_HORKAGE_NODMA },
4300 	{ "Seagate STT20000A", NULL,		ATA_HORKAGE_NODMA },
4301 	{ " 2GB ATA Flash Disk", "ADMA428M",	ATA_HORKAGE_NODMA },
4302 	{ "VRFDFC22048UCHC-TE*", NULL,		ATA_HORKAGE_NODMA },
4303 	/* Odd clown on sil3726/4726 PMPs */
4304 	{ "Config  Disk",	NULL,		ATA_HORKAGE_DISABLE },
4305 
4306 	/* Weird ATAPI devices */
4307 	{ "TORiSAN DVD-ROM DRD-N216", NULL,	ATA_HORKAGE_MAX_SEC_128 },
4308 	{ "QUANTUM DAT    DAT72-000", NULL,	ATA_HORKAGE_ATAPI_MOD16_DMA },
4309 	{ "Slimtype DVD A  DS8A8SH", NULL,	ATA_HORKAGE_MAX_SEC_LBA48 },
4310 	{ "Slimtype DVD A  DS8A9SH", NULL,	ATA_HORKAGE_MAX_SEC_LBA48 },
4311 
4312 	/*
4313 	 * Causes silent data corruption with higher max sects.
4314 	 * http://lkml.kernel.org/g/x49wpy40ysk.fsf@segfault.boston.devel.redhat.com
4315 	 */
4316 	{ "ST380013AS",		"3.20",		ATA_HORKAGE_MAX_SEC_1024 },
4317 
4318 	/*
4319 	 * Device times out with higher max sects.
4320 	 * https://bugzilla.kernel.org/show_bug.cgi?id=121671
4321 	 */
4322 	{ "LITEON CX1-JB256-HP", NULL,		ATA_HORKAGE_MAX_SEC_1024 },
4323 
4324 	/* Devices we expect to fail diagnostics */
4325 
4326 	/* Devices where NCQ should be avoided */
4327 	/* NCQ is slow */
4328 	{ "WDC WD740ADFD-00",	NULL,		ATA_HORKAGE_NONCQ },
4329 	{ "WDC WD740ADFD-00NLR1", NULL,		ATA_HORKAGE_NONCQ, },
4330 	/* http://thread.gmane.org/gmane.linux.ide/14907 */
4331 	{ "FUJITSU MHT2060BH",	NULL,		ATA_HORKAGE_NONCQ },
4332 	/* NCQ is broken */
4333 	{ "Maxtor *",		"BANC*",	ATA_HORKAGE_NONCQ },
4334 	{ "Maxtor 7V300F0",	"VA111630",	ATA_HORKAGE_NONCQ },
4335 	{ "ST380817AS",		"3.42",		ATA_HORKAGE_NONCQ },
4336 	{ "ST3160023AS",	"3.42",		ATA_HORKAGE_NONCQ },
4337 	{ "OCZ CORE_SSD",	"02.10104",	ATA_HORKAGE_NONCQ },
4338 
4339 	/* Seagate NCQ + FLUSH CACHE firmware bug */
4340 	{ "ST31500341AS",	"SD1[5-9]",	ATA_HORKAGE_NONCQ |
4341 						ATA_HORKAGE_FIRMWARE_WARN },
4342 
4343 	{ "ST31000333AS",	"SD1[5-9]",	ATA_HORKAGE_NONCQ |
4344 						ATA_HORKAGE_FIRMWARE_WARN },
4345 
4346 	{ "ST3640[36]23AS",	"SD1[5-9]",	ATA_HORKAGE_NONCQ |
4347 						ATA_HORKAGE_FIRMWARE_WARN },
4348 
4349 	{ "ST3320[68]13AS",	"SD1[5-9]",	ATA_HORKAGE_NONCQ |
4350 						ATA_HORKAGE_FIRMWARE_WARN },
4351 
4352 	/* drives which fail FPDMA_AA activation (some may freeze afterwards) */
4353 	{ "ST1000LM024 HN-M101MBB", "2AR10001",	ATA_HORKAGE_BROKEN_FPDMA_AA },
4354 	{ "ST1000LM024 HN-M101MBB", "2BA30001",	ATA_HORKAGE_BROKEN_FPDMA_AA },
4355 	{ "VB0250EAVER",	"HPG7",		ATA_HORKAGE_BROKEN_FPDMA_AA },
4356 
4357 	/* Blacklist entries taken from Silicon Image 3124/3132
4358 	   Windows driver .inf file - also several Linux problem reports */
4359 	{ "HTS541060G9SA00",    "MB3OC60D",     ATA_HORKAGE_NONCQ, },
4360 	{ "HTS541080G9SA00",    "MB4OC60D",     ATA_HORKAGE_NONCQ, },
4361 	{ "HTS541010G9SA00",    "MBZOC60D",     ATA_HORKAGE_NONCQ, },
4362 
4363 	/* https://bugzilla.kernel.org/show_bug.cgi?id=15573 */
4364 	{ "C300-CTFDDAC128MAG",	"0001",		ATA_HORKAGE_NONCQ, },
4365 
4366 	/* devices which puke on READ_NATIVE_MAX */
4367 	{ "HDS724040KLSA80",	"KFAOA20N",	ATA_HORKAGE_BROKEN_HPA, },
4368 	{ "WDC WD3200JD-00KLB0", "WD-WCAMR1130137", ATA_HORKAGE_BROKEN_HPA },
4369 	{ "WDC WD2500JD-00HBB0", "WD-WMAL71490727", ATA_HORKAGE_BROKEN_HPA },
4370 	{ "MAXTOR 6L080L4",	"A93.0500",	ATA_HORKAGE_BROKEN_HPA },
4371 
4372 	/* this one allows HPA unlocking but fails IOs on the area */
4373 	{ "OCZ-VERTEX",		    "1.30",	ATA_HORKAGE_BROKEN_HPA },
4374 
4375 	/* Devices which report 1 sector over size HPA */
4376 	{ "ST340823A",		NULL,		ATA_HORKAGE_HPA_SIZE, },
4377 	{ "ST320413A",		NULL,		ATA_HORKAGE_HPA_SIZE, },
4378 	{ "ST310211A",		NULL,		ATA_HORKAGE_HPA_SIZE, },
4379 
4380 	/* Devices which get the IVB wrong */
4381 	{ "QUANTUM FIREBALLlct10 05", "A03.0900", ATA_HORKAGE_IVB, },
4382 	/* Maybe we should just blacklist TSSTcorp... */
4383 	{ "TSSTcorp CDDVDW SH-S202[HJN]", "SB0[01]",  ATA_HORKAGE_IVB, },
4384 
4385 	/* Devices that do not need bridging limits applied */
4386 	{ "MTRON MSP-SATA*",		NULL,	ATA_HORKAGE_BRIDGE_OK, },
4387 	{ "BUFFALO HD-QSU2/R5",		NULL,	ATA_HORKAGE_BRIDGE_OK, },
4388 
4389 	/* Devices which aren't very happy with higher link speeds */
4390 	{ "WD My Book",			NULL,	ATA_HORKAGE_1_5_GBPS, },
4391 	{ "Seagate FreeAgent GoFlex",	NULL,	ATA_HORKAGE_1_5_GBPS, },
4392 
4393 	/*
4394 	 * Devices which choke on SETXFER.  Applies only if both the
4395 	 * device and controller are SATA.
4396 	 */
4397 	{ "PIONEER DVD-RW  DVRTD08",	NULL,	ATA_HORKAGE_NOSETXFER },
4398 	{ "PIONEER DVD-RW  DVRTD08A",	NULL,	ATA_HORKAGE_NOSETXFER },
4399 	{ "PIONEER DVD-RW  DVR-215",	NULL,	ATA_HORKAGE_NOSETXFER },
4400 	{ "PIONEER DVD-RW  DVR-212D",	NULL,	ATA_HORKAGE_NOSETXFER },
4401 	{ "PIONEER DVD-RW  DVR-216D",	NULL,	ATA_HORKAGE_NOSETXFER },
4402 
4403 	/* devices that don't properly handle queued TRIM commands */
4404 	{ "Micron_M500_*",		NULL,	ATA_HORKAGE_NO_NCQ_TRIM |
4405 						ATA_HORKAGE_ZERO_AFTER_TRIM, },
4406 	{ "Crucial_CT*M500*",		NULL,	ATA_HORKAGE_NO_NCQ_TRIM |
4407 						ATA_HORKAGE_ZERO_AFTER_TRIM, },
4408 	{ "Micron_M5[15]0_*",		"MU01",	ATA_HORKAGE_NO_NCQ_TRIM |
4409 						ATA_HORKAGE_ZERO_AFTER_TRIM, },
4410 	{ "Crucial_CT*M550*",		"MU01",	ATA_HORKAGE_NO_NCQ_TRIM |
4411 						ATA_HORKAGE_ZERO_AFTER_TRIM, },
4412 	{ "Crucial_CT*MX100*",		"MU01",	ATA_HORKAGE_NO_NCQ_TRIM |
4413 						ATA_HORKAGE_ZERO_AFTER_TRIM, },
4414 	{ "Samsung SSD 8*",		NULL,	ATA_HORKAGE_NO_NCQ_TRIM |
4415 						ATA_HORKAGE_ZERO_AFTER_TRIM, },
4416 	{ "FCCT*M500*",			NULL,	ATA_HORKAGE_NO_NCQ_TRIM |
4417 						ATA_HORKAGE_ZERO_AFTER_TRIM, },
4418 
4419 	/* devices that don't properly handle TRIM commands */
4420 	{ "SuperSSpeed S238*",		NULL,	ATA_HORKAGE_NOTRIM, },
4421 
4422 	/*
4423 	 * As defined, the DRAT (Deterministic Read After Trim) and RZAT
4424 	 * (Return Zero After Trim) flags in the ATA Command Set are
4425 	 * unreliable in the sense that they only define what happens if
4426 	 * the device successfully executed the DSM TRIM command. TRIM
4427 	 * is only advisory, however, and the device is free to silently
4428 	 * ignore all or parts of the request.
4429 	 *
4430 	 * Whitelist drives that are known to reliably return zeroes
4431 	 * after TRIM.
4432 	 */
4433 
4434 	/*
4435 	 * The intel 510 drive has buggy DRAT/RZAT. Explicitly exclude
4436 	 * that model before whitelisting all other intel SSDs.
4437 	 */
4438 	{ "INTEL*SSDSC2MH*",		NULL,	0, },
4439 
4440 	{ "Micron*",			NULL,	ATA_HORKAGE_ZERO_AFTER_TRIM, },
4441 	{ "Crucial*",			NULL,	ATA_HORKAGE_ZERO_AFTER_TRIM, },
4442 	{ "INTEL*SSD*", 		NULL,	ATA_HORKAGE_ZERO_AFTER_TRIM, },
4443 	{ "SSD*INTEL*",			NULL,	ATA_HORKAGE_ZERO_AFTER_TRIM, },
4444 	{ "Samsung*SSD*",		NULL,	ATA_HORKAGE_ZERO_AFTER_TRIM, },
4445 	{ "SAMSUNG*SSD*",		NULL,	ATA_HORKAGE_ZERO_AFTER_TRIM, },
4446 	{ "ST[1248][0248]0[FH]*",	NULL,	ATA_HORKAGE_ZERO_AFTER_TRIM, },
4447 
4448 	/*
4449 	 * Some WD SATA-I drives spin up and down erratically when the link
4450 	 * is put into the slumber mode.  We don't have full list of the
4451 	 * affected devices.  Disable LPM if the device matches one of the
4452 	 * known prefixes and is SATA-1.  As a side effect LPM partial is
4453 	 * lost too.
4454 	 *
4455 	 * https://bugzilla.kernel.org/show_bug.cgi?id=57211
4456 	 */
4457 	{ "WDC WD800JD-*",		NULL,	ATA_HORKAGE_WD_BROKEN_LPM },
4458 	{ "WDC WD1200JD-*",		NULL,	ATA_HORKAGE_WD_BROKEN_LPM },
4459 	{ "WDC WD1600JD-*",		NULL,	ATA_HORKAGE_WD_BROKEN_LPM },
4460 	{ "WDC WD2000JD-*",		NULL,	ATA_HORKAGE_WD_BROKEN_LPM },
4461 	{ "WDC WD2500JD-*",		NULL,	ATA_HORKAGE_WD_BROKEN_LPM },
4462 	{ "WDC WD3000JD-*",		NULL,	ATA_HORKAGE_WD_BROKEN_LPM },
4463 	{ "WDC WD3200JD-*",		NULL,	ATA_HORKAGE_WD_BROKEN_LPM },
4464 
4465 	/* End Marker */
4466 	{ }
4467 };
4468 
4469 static unsigned long ata_dev_blacklisted(const struct ata_device *dev)
4470 {
4471 	unsigned char model_num[ATA_ID_PROD_LEN + 1];
4472 	unsigned char model_rev[ATA_ID_FW_REV_LEN + 1];
4473 	const struct ata_blacklist_entry *ad = ata_device_blacklist;
4474 
4475 	ata_id_c_string(dev->id, model_num, ATA_ID_PROD, sizeof(model_num));
4476 	ata_id_c_string(dev->id, model_rev, ATA_ID_FW_REV, sizeof(model_rev));
4477 
4478 	while (ad->model_num) {
4479 		if (glob_match(ad->model_num, model_num)) {
4480 			if (ad->model_rev == NULL)
4481 				return ad->horkage;
4482 			if (glob_match(ad->model_rev, model_rev))
4483 				return ad->horkage;
4484 		}
4485 		ad++;
4486 	}
4487 	return 0;
4488 }
4489 
4490 static int ata_dma_blacklisted(const struct ata_device *dev)
4491 {
4492 	/* We don't support polling DMA.
4493 	 * DMA blacklist those ATAPI devices with CDB-intr (and use PIO)
4494 	 * if the LLDD handles only interrupts in the HSM_ST_LAST state.
4495 	 */
4496 	if ((dev->link->ap->flags & ATA_FLAG_PIO_POLLING) &&
4497 	    (dev->flags & ATA_DFLAG_CDB_INTR))
4498 		return 1;
4499 	return (dev->horkage & ATA_HORKAGE_NODMA) ? 1 : 0;
4500 }
4501 
4502 /**
4503  *	ata_is_40wire		-	check drive side detection
4504  *	@dev: device
4505  *
4506  *	Perform drive side detection decoding, allowing for device vendors
4507  *	who can't follow the documentation.
4508  */
4509 
4510 static int ata_is_40wire(struct ata_device *dev)
4511 {
4512 	if (dev->horkage & ATA_HORKAGE_IVB)
4513 		return ata_drive_40wire_relaxed(dev->id);
4514 	return ata_drive_40wire(dev->id);
4515 }
4516 
4517 /**
4518  *	cable_is_40wire		-	40/80/SATA decider
4519  *	@ap: port to consider
4520  *
4521  *	This function encapsulates the policy for speed management
4522  *	in one place. At the moment we don't cache the result but
4523  *	there is a good case for setting ap->cbl to the result when
4524  *	we are called with unknown cables (and figuring out if it
4525  *	impacts hotplug at all).
4526  *
4527  *	Return 1 if the cable appears to be 40 wire.
4528  */
4529 
4530 static int cable_is_40wire(struct ata_port *ap)
4531 {
4532 	struct ata_link *link;
4533 	struct ata_device *dev;
4534 
4535 	/* If the controller thinks we are 40 wire, we are. */
4536 	if (ap->cbl == ATA_CBL_PATA40)
4537 		return 1;
4538 
4539 	/* If the controller thinks we are 80 wire, we are. */
4540 	if (ap->cbl == ATA_CBL_PATA80 || ap->cbl == ATA_CBL_SATA)
4541 		return 0;
4542 
4543 	/* If the system is known to be 40 wire short cable (eg
4544 	 * laptop), then we allow 80 wire modes even if the drive
4545 	 * isn't sure.
4546 	 */
4547 	if (ap->cbl == ATA_CBL_PATA40_SHORT)
4548 		return 0;
4549 
4550 	/* If the controller doesn't know, we scan.
4551 	 *
4552 	 * Note: We look for all 40 wire detects at this point.  Any
4553 	 *       80 wire detect is taken to be 80 wire cable because
4554 	 * - in many setups only the one drive (slave if present) will
4555 	 *   give a valid detect
4556 	 * - if you have a non detect capable drive you don't want it
4557 	 *   to colour the choice
4558 	 */
4559 	ata_for_each_link(link, ap, EDGE) {
4560 		ata_for_each_dev(dev, link, ENABLED) {
4561 			if (!ata_is_40wire(dev))
4562 				return 0;
4563 		}
4564 	}
4565 	return 1;
4566 }
4567 
4568 /**
4569  *	ata_dev_xfermask - Compute supported xfermask of the given device
4570  *	@dev: Device to compute xfermask for
4571  *
4572  *	Compute supported xfermask of @dev and store it in
4573  *	dev->*_mask.  This function is responsible for applying all
4574  *	known limits including host controller limits, device
4575  *	blacklist, etc...
4576  *
4577  *	LOCKING:
4578  *	None.
4579  */
4580 static void ata_dev_xfermask(struct ata_device *dev)
4581 {
4582 	struct ata_link *link = dev->link;
4583 	struct ata_port *ap = link->ap;
4584 	struct ata_host *host = ap->host;
4585 	unsigned long xfer_mask;
4586 
4587 	/* controller modes available */
4588 	xfer_mask = ata_pack_xfermask(ap->pio_mask,
4589 				      ap->mwdma_mask, ap->udma_mask);
4590 
4591 	/* drive modes available */
4592 	xfer_mask &= ata_pack_xfermask(dev->pio_mask,
4593 				       dev->mwdma_mask, dev->udma_mask);
4594 	xfer_mask &= ata_id_xfermask(dev->id);
4595 
4596 	/*
4597 	 *	CFA Advanced TrueIDE timings are not allowed on a shared
4598 	 *	cable
4599 	 */
4600 	if (ata_dev_pair(dev)) {
4601 		/* No PIO5 or PIO6 */
4602 		xfer_mask &= ~(0x03 << (ATA_SHIFT_PIO + 5));
4603 		/* No MWDMA3 or MWDMA 4 */
4604 		xfer_mask &= ~(0x03 << (ATA_SHIFT_MWDMA + 3));
4605 	}
4606 
4607 	if (ata_dma_blacklisted(dev)) {
4608 		xfer_mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA);
4609 		ata_dev_warn(dev,
4610 			     "device is on DMA blacklist, disabling DMA\n");
4611 	}
4612 
4613 	if ((host->flags & ATA_HOST_SIMPLEX) &&
4614 	    host->simplex_claimed && host->simplex_claimed != ap) {
4615 		xfer_mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA);
4616 		ata_dev_warn(dev,
4617 			     "simplex DMA is claimed by other device, disabling DMA\n");
4618 	}
4619 
4620 	if (ap->flags & ATA_FLAG_NO_IORDY)
4621 		xfer_mask &= ata_pio_mask_no_iordy(dev);
4622 
4623 	if (ap->ops->mode_filter)
4624 		xfer_mask = ap->ops->mode_filter(dev, xfer_mask);
4625 
4626 	/* Apply cable rule here.  Don't apply it early because when
4627 	 * we handle hot plug the cable type can itself change.
4628 	 * Check this last so that we know if the transfer rate was
4629 	 * solely limited by the cable.
4630 	 * Unknown or 80 wire cables reported host side are checked
4631 	 * drive side as well. Cases where we know a 40wire cable
4632 	 * is used safely for 80 are not checked here.
4633 	 */
4634 	if (xfer_mask & (0xF8 << ATA_SHIFT_UDMA))
4635 		/* UDMA/44 or higher would be available */
4636 		if (cable_is_40wire(ap)) {
4637 			ata_dev_warn(dev,
4638 				     "limited to UDMA/33 due to 40-wire cable\n");
4639 			xfer_mask &= ~(0xF8 << ATA_SHIFT_UDMA);
4640 		}
4641 
4642 	ata_unpack_xfermask(xfer_mask, &dev->pio_mask,
4643 			    &dev->mwdma_mask, &dev->udma_mask);
4644 }
4645 
4646 /**
4647  *	ata_dev_set_xfermode - Issue SET FEATURES - XFER MODE command
4648  *	@dev: Device to which command will be sent
4649  *
4650  *	Issue SET FEATURES - XFER MODE command to device @dev
4651  *	on port @ap.
4652  *
4653  *	LOCKING:
4654  *	PCI/etc. bus probe sem.
4655  *
4656  *	RETURNS:
4657  *	0 on success, AC_ERR_* mask otherwise.
4658  */
4659 
4660 static unsigned int ata_dev_set_xfermode(struct ata_device *dev)
4661 {
4662 	struct ata_taskfile tf;
4663 	unsigned int err_mask;
4664 
4665 	/* set up set-features taskfile */
4666 	DPRINTK("set features - xfer mode\n");
4667 
4668 	/* Some controllers and ATAPI devices show flaky interrupt
4669 	 * behavior after setting xfer mode.  Use polling instead.
4670 	 */
4671 	ata_tf_init(dev, &tf);
4672 	tf.command = ATA_CMD_SET_FEATURES;
4673 	tf.feature = SETFEATURES_XFER;
4674 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE | ATA_TFLAG_POLLING;
4675 	tf.protocol = ATA_PROT_NODATA;
4676 	/* If we are using IORDY we must send the mode setting command */
4677 	if (ata_pio_need_iordy(dev))
4678 		tf.nsect = dev->xfer_mode;
4679 	/* If the device has IORDY and the controller does not - turn it off */
4680  	else if (ata_id_has_iordy(dev->id))
4681 		tf.nsect = 0x01;
4682 	else /* In the ancient relic department - skip all of this */
4683 		return 0;
4684 
4685 	/* On some disks, this command causes spin-up, so we need longer timeout */
4686 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 15000);
4687 
4688 	DPRINTK("EXIT, err_mask=%x\n", err_mask);
4689 	return err_mask;
4690 }
4691 
4692 /**
4693  *	ata_dev_set_feature - Issue SET FEATURES - SATA FEATURES
4694  *	@dev: Device to which command will be sent
4695  *	@enable: Whether to enable or disable the feature
4696  *	@feature: The sector count represents the feature to set
4697  *
4698  *	Issue SET FEATURES - SATA FEATURES command to device @dev
4699  *	on port @ap with sector count
4700  *
4701  *	LOCKING:
4702  *	PCI/etc. bus probe sem.
4703  *
4704  *	RETURNS:
4705  *	0 on success, AC_ERR_* mask otherwise.
4706  */
4707 unsigned int ata_dev_set_feature(struct ata_device *dev, u8 enable, u8 feature)
4708 {
4709 	struct ata_taskfile tf;
4710 	unsigned int err_mask;
4711 	unsigned long timeout = 0;
4712 
4713 	/* set up set-features taskfile */
4714 	DPRINTK("set features - SATA features\n");
4715 
4716 	ata_tf_init(dev, &tf);
4717 	tf.command = ATA_CMD_SET_FEATURES;
4718 	tf.feature = enable;
4719 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
4720 	tf.protocol = ATA_PROT_NODATA;
4721 	tf.nsect = feature;
4722 
4723 	if (enable == SETFEATURES_SPINUP)
4724 		timeout = ata_probe_timeout ?
4725 			  ata_probe_timeout * 1000 : SETFEATURES_SPINUP_TIMEOUT;
4726 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, timeout);
4727 
4728 	DPRINTK("EXIT, err_mask=%x\n", err_mask);
4729 	return err_mask;
4730 }
4731 EXPORT_SYMBOL_GPL(ata_dev_set_feature);
4732 
4733 /**
4734  *	ata_dev_init_params - Issue INIT DEV PARAMS command
4735  *	@dev: Device to which command will be sent
4736  *	@heads: Number of heads (taskfile parameter)
4737  *	@sectors: Number of sectors (taskfile parameter)
4738  *
4739  *	LOCKING:
4740  *	Kernel thread context (may sleep)
4741  *
4742  *	RETURNS:
4743  *	0 on success, AC_ERR_* mask otherwise.
4744  */
4745 static unsigned int ata_dev_init_params(struct ata_device *dev,
4746 					u16 heads, u16 sectors)
4747 {
4748 	struct ata_taskfile tf;
4749 	unsigned int err_mask;
4750 
4751 	/* Number of sectors per track 1-255. Number of heads 1-16 */
4752 	if (sectors < 1 || sectors > 255 || heads < 1 || heads > 16)
4753 		return AC_ERR_INVALID;
4754 
4755 	/* set up init dev params taskfile */
4756 	DPRINTK("init dev params \n");
4757 
4758 	ata_tf_init(dev, &tf);
4759 	tf.command = ATA_CMD_INIT_DEV_PARAMS;
4760 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
4761 	tf.protocol = ATA_PROT_NODATA;
4762 	tf.nsect = sectors;
4763 	tf.device |= (heads - 1) & 0x0f; /* max head = num. of heads - 1 */
4764 
4765 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
4766 	/* A clean abort indicates an original or just out of spec drive
4767 	   and we should continue as we issue the setup based on the
4768 	   drive reported working geometry */
4769 	if (err_mask == AC_ERR_DEV && (tf.feature & ATA_ABORTED))
4770 		err_mask = 0;
4771 
4772 	DPRINTK("EXIT, err_mask=%x\n", err_mask);
4773 	return err_mask;
4774 }
4775 
4776 /**
4777  *	ata_sg_clean - Unmap DMA memory associated with command
4778  *	@qc: Command containing DMA memory to be released
4779  *
4780  *	Unmap all mapped DMA memory associated with this command.
4781  *
4782  *	LOCKING:
4783  *	spin_lock_irqsave(host lock)
4784  */
4785 void ata_sg_clean(struct ata_queued_cmd *qc)
4786 {
4787 	struct ata_port *ap = qc->ap;
4788 	struct scatterlist *sg = qc->sg;
4789 	int dir = qc->dma_dir;
4790 
4791 	WARN_ON_ONCE(sg == NULL);
4792 
4793 	VPRINTK("unmapping %u sg elements\n", qc->n_elem);
4794 
4795 	if (qc->n_elem)
4796 		dma_unmap_sg(ap->dev, sg, qc->orig_n_elem, dir);
4797 
4798 	qc->flags &= ~ATA_QCFLAG_DMAMAP;
4799 	qc->sg = NULL;
4800 }
4801 
4802 /**
4803  *	atapi_check_dma - Check whether ATAPI DMA can be supported
4804  *	@qc: Metadata associated with taskfile to check
4805  *
4806  *	Allow low-level driver to filter ATA PACKET commands, returning
4807  *	a status indicating whether or not it is OK to use DMA for the
4808  *	supplied PACKET command.
4809  *
4810  *	LOCKING:
4811  *	spin_lock_irqsave(host lock)
4812  *
4813  *	RETURNS: 0 when ATAPI DMA can be used
4814  *               nonzero otherwise
4815  */
4816 int atapi_check_dma(struct ata_queued_cmd *qc)
4817 {
4818 	struct ata_port *ap = qc->ap;
4819 
4820 	/* Don't allow DMA if it isn't multiple of 16 bytes.  Quite a
4821 	 * few ATAPI devices choke on such DMA requests.
4822 	 */
4823 	if (!(qc->dev->horkage & ATA_HORKAGE_ATAPI_MOD16_DMA) &&
4824 	    unlikely(qc->nbytes & 15))
4825 		return 1;
4826 
4827 	if (ap->ops->check_atapi_dma)
4828 		return ap->ops->check_atapi_dma(qc);
4829 
4830 	return 0;
4831 }
4832 
4833 /**
4834  *	ata_std_qc_defer - Check whether a qc needs to be deferred
4835  *	@qc: ATA command in question
4836  *
4837  *	Non-NCQ commands cannot run with any other command, NCQ or
4838  *	not.  As upper layer only knows the queue depth, we are
4839  *	responsible for maintaining exclusion.  This function checks
4840  *	whether a new command @qc can be issued.
4841  *
4842  *	LOCKING:
4843  *	spin_lock_irqsave(host lock)
4844  *
4845  *	RETURNS:
4846  *	ATA_DEFER_* if deferring is needed, 0 otherwise.
4847  */
4848 int ata_std_qc_defer(struct ata_queued_cmd *qc)
4849 {
4850 	struct ata_link *link = qc->dev->link;
4851 
4852 	if (ata_is_ncq(qc->tf.protocol)) {
4853 		if (!ata_tag_valid(link->active_tag))
4854 			return 0;
4855 	} else {
4856 		if (!ata_tag_valid(link->active_tag) && !link->sactive)
4857 			return 0;
4858 	}
4859 
4860 	return ATA_DEFER_LINK;
4861 }
4862 
4863 void ata_noop_qc_prep(struct ata_queued_cmd *qc) { }
4864 
4865 /**
4866  *	ata_sg_init - Associate command with scatter-gather table.
4867  *	@qc: Command to be associated
4868  *	@sg: Scatter-gather table.
4869  *	@n_elem: Number of elements in s/g table.
4870  *
4871  *	Initialize the data-related elements of queued_cmd @qc
4872  *	to point to a scatter-gather table @sg, containing @n_elem
4873  *	elements.
4874  *
4875  *	LOCKING:
4876  *	spin_lock_irqsave(host lock)
4877  */
4878 void ata_sg_init(struct ata_queued_cmd *qc, struct scatterlist *sg,
4879 		 unsigned int n_elem)
4880 {
4881 	qc->sg = sg;
4882 	qc->n_elem = n_elem;
4883 	qc->cursg = qc->sg;
4884 }
4885 
4886 /**
4887  *	ata_sg_setup - DMA-map the scatter-gather table associated with a command.
4888  *	@qc: Command with scatter-gather table to be mapped.
4889  *
4890  *	DMA-map the scatter-gather table associated with queued_cmd @qc.
4891  *
4892  *	LOCKING:
4893  *	spin_lock_irqsave(host lock)
4894  *
4895  *	RETURNS:
4896  *	Zero on success, negative on error.
4897  *
4898  */
4899 static int ata_sg_setup(struct ata_queued_cmd *qc)
4900 {
4901 	struct ata_port *ap = qc->ap;
4902 	unsigned int n_elem;
4903 
4904 	VPRINTK("ENTER, ata%u\n", ap->print_id);
4905 
4906 	n_elem = dma_map_sg(ap->dev, qc->sg, qc->n_elem, qc->dma_dir);
4907 	if (n_elem < 1)
4908 		return -1;
4909 
4910 	DPRINTK("%d sg elements mapped\n", n_elem);
4911 	qc->orig_n_elem = qc->n_elem;
4912 	qc->n_elem = n_elem;
4913 	qc->flags |= ATA_QCFLAG_DMAMAP;
4914 
4915 	return 0;
4916 }
4917 
4918 /**
4919  *	swap_buf_le16 - swap halves of 16-bit words in place
4920  *	@buf:  Buffer to swap
4921  *	@buf_words:  Number of 16-bit words in buffer.
4922  *
4923  *	Swap halves of 16-bit words if needed to convert from
4924  *	little-endian byte order to native cpu byte order, or
4925  *	vice-versa.
4926  *
4927  *	LOCKING:
4928  *	Inherited from caller.
4929  */
4930 void swap_buf_le16(u16 *buf, unsigned int buf_words)
4931 {
4932 #ifdef __BIG_ENDIAN
4933 	unsigned int i;
4934 
4935 	for (i = 0; i < buf_words; i++)
4936 		buf[i] = le16_to_cpu(buf[i]);
4937 #endif /* __BIG_ENDIAN */
4938 }
4939 
4940 /**
4941  *	ata_qc_new_init - Request an available ATA command, and initialize it
4942  *	@dev: Device from whom we request an available command structure
4943  *	@tag: tag
4944  *
4945  *	LOCKING:
4946  *	None.
4947  */
4948 
4949 struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev, int tag)
4950 {
4951 	struct ata_port *ap = dev->link->ap;
4952 	struct ata_queued_cmd *qc;
4953 
4954 	/* no command while frozen */
4955 	if (unlikely(ap->pflags & ATA_PFLAG_FROZEN))
4956 		return NULL;
4957 
4958 	/* libsas case */
4959 	if (ap->flags & ATA_FLAG_SAS_HOST) {
4960 		tag = ata_sas_allocate_tag(ap);
4961 		if (tag < 0)
4962 			return NULL;
4963 	}
4964 
4965 	qc = __ata_qc_from_tag(ap, tag);
4966 	qc->tag = tag;
4967 	qc->scsicmd = NULL;
4968 	qc->ap = ap;
4969 	qc->dev = dev;
4970 
4971 	ata_qc_reinit(qc);
4972 
4973 	return qc;
4974 }
4975 
4976 /**
4977  *	ata_qc_free - free unused ata_queued_cmd
4978  *	@qc: Command to complete
4979  *
4980  *	Designed to free unused ata_queued_cmd object
4981  *	in case something prevents using it.
4982  *
4983  *	LOCKING:
4984  *	spin_lock_irqsave(host lock)
4985  */
4986 void ata_qc_free(struct ata_queued_cmd *qc)
4987 {
4988 	struct ata_port *ap;
4989 	unsigned int tag;
4990 
4991 	WARN_ON_ONCE(qc == NULL); /* ata_qc_from_tag _might_ return NULL */
4992 	ap = qc->ap;
4993 
4994 	qc->flags = 0;
4995 	tag = qc->tag;
4996 	if (likely(ata_tag_valid(tag))) {
4997 		qc->tag = ATA_TAG_POISON;
4998 		if (ap->flags & ATA_FLAG_SAS_HOST)
4999 			ata_sas_free_tag(tag, ap);
5000 	}
5001 }
5002 
5003 void __ata_qc_complete(struct ata_queued_cmd *qc)
5004 {
5005 	struct ata_port *ap;
5006 	struct ata_link *link;
5007 
5008 	WARN_ON_ONCE(qc == NULL); /* ata_qc_from_tag _might_ return NULL */
5009 	WARN_ON_ONCE(!(qc->flags & ATA_QCFLAG_ACTIVE));
5010 	ap = qc->ap;
5011 	link = qc->dev->link;
5012 
5013 	if (likely(qc->flags & ATA_QCFLAG_DMAMAP))
5014 		ata_sg_clean(qc);
5015 
5016 	/* command should be marked inactive atomically with qc completion */
5017 	if (ata_is_ncq(qc->tf.protocol)) {
5018 		link->sactive &= ~(1 << qc->tag);
5019 		if (!link->sactive)
5020 			ap->nr_active_links--;
5021 	} else {
5022 		link->active_tag = ATA_TAG_POISON;
5023 		ap->nr_active_links--;
5024 	}
5025 
5026 	/* clear exclusive status */
5027 	if (unlikely(qc->flags & ATA_QCFLAG_CLEAR_EXCL &&
5028 		     ap->excl_link == link))
5029 		ap->excl_link = NULL;
5030 
5031 	/* atapi: mark qc as inactive to prevent the interrupt handler
5032 	 * from completing the command twice later, before the error handler
5033 	 * is called. (when rc != 0 and atapi request sense is needed)
5034 	 */
5035 	qc->flags &= ~ATA_QCFLAG_ACTIVE;
5036 	ap->qc_active &= ~(1 << qc->tag);
5037 
5038 	/* call completion callback */
5039 	qc->complete_fn(qc);
5040 }
5041 
5042 static void fill_result_tf(struct ata_queued_cmd *qc)
5043 {
5044 	struct ata_port *ap = qc->ap;
5045 
5046 	qc->result_tf.flags = qc->tf.flags;
5047 	ap->ops->qc_fill_rtf(qc);
5048 }
5049 
5050 static void ata_verify_xfer(struct ata_queued_cmd *qc)
5051 {
5052 	struct ata_device *dev = qc->dev;
5053 
5054 	if (!ata_is_data(qc->tf.protocol))
5055 		return;
5056 
5057 	if ((dev->mwdma_mask || dev->udma_mask) && ata_is_pio(qc->tf.protocol))
5058 		return;
5059 
5060 	dev->flags &= ~ATA_DFLAG_DUBIOUS_XFER;
5061 }
5062 
5063 /**
5064  *	ata_qc_complete - Complete an active ATA command
5065  *	@qc: Command to complete
5066  *
5067  *	Indicate to the mid and upper layers that an ATA command has
5068  *	completed, with either an ok or not-ok status.
5069  *
5070  *	Refrain from calling this function multiple times when
5071  *	successfully completing multiple NCQ commands.
5072  *	ata_qc_complete_multiple() should be used instead, which will
5073  *	properly update IRQ expect state.
5074  *
5075  *	LOCKING:
5076  *	spin_lock_irqsave(host lock)
5077  */
5078 void ata_qc_complete(struct ata_queued_cmd *qc)
5079 {
5080 	struct ata_port *ap = qc->ap;
5081 
5082 	/* Trigger the LED (if available) */
5083 	ledtrig_disk_activity();
5084 
5085 	/* XXX: New EH and old EH use different mechanisms to
5086 	 * synchronize EH with regular execution path.
5087 	 *
5088 	 * In new EH, a failed qc is marked with ATA_QCFLAG_FAILED.
5089 	 * Normal execution path is responsible for not accessing a
5090 	 * failed qc.  libata core enforces the rule by returning NULL
5091 	 * from ata_qc_from_tag() for failed qcs.
5092 	 *
5093 	 * Old EH depends on ata_qc_complete() nullifying completion
5094 	 * requests if ATA_QCFLAG_EH_SCHEDULED is set.  Old EH does
5095 	 * not synchronize with interrupt handler.  Only PIO task is
5096 	 * taken care of.
5097 	 */
5098 	if (ap->ops->error_handler) {
5099 		struct ata_device *dev = qc->dev;
5100 		struct ata_eh_info *ehi = &dev->link->eh_info;
5101 
5102 		if (unlikely(qc->err_mask))
5103 			qc->flags |= ATA_QCFLAG_FAILED;
5104 
5105 		/*
5106 		 * Finish internal commands without any further processing
5107 		 * and always with the result TF filled.
5108 		 */
5109 		if (unlikely(ata_tag_internal(qc->tag))) {
5110 			fill_result_tf(qc);
5111 			trace_ata_qc_complete_internal(qc);
5112 			__ata_qc_complete(qc);
5113 			return;
5114 		}
5115 
5116 		/*
5117 		 * Non-internal qc has failed.  Fill the result TF and
5118 		 * summon EH.
5119 		 */
5120 		if (unlikely(qc->flags & ATA_QCFLAG_FAILED)) {
5121 			fill_result_tf(qc);
5122 			trace_ata_qc_complete_failed(qc);
5123 			ata_qc_schedule_eh(qc);
5124 			return;
5125 		}
5126 
5127 		WARN_ON_ONCE(ap->pflags & ATA_PFLAG_FROZEN);
5128 
5129 		/* read result TF if requested */
5130 		if (qc->flags & ATA_QCFLAG_RESULT_TF)
5131 			fill_result_tf(qc);
5132 
5133 		trace_ata_qc_complete_done(qc);
5134 		/* Some commands need post-processing after successful
5135 		 * completion.
5136 		 */
5137 		switch (qc->tf.command) {
5138 		case ATA_CMD_SET_FEATURES:
5139 			if (qc->tf.feature != SETFEATURES_WC_ON &&
5140 			    qc->tf.feature != SETFEATURES_WC_OFF &&
5141 			    qc->tf.feature != SETFEATURES_RA_ON &&
5142 			    qc->tf.feature != SETFEATURES_RA_OFF)
5143 				break;
5144 			/* fall through */
5145 		case ATA_CMD_INIT_DEV_PARAMS: /* CHS translation changed */
5146 		case ATA_CMD_SET_MULTI: /* multi_count changed */
5147 			/* revalidate device */
5148 			ehi->dev_action[dev->devno] |= ATA_EH_REVALIDATE;
5149 			ata_port_schedule_eh(ap);
5150 			break;
5151 
5152 		case ATA_CMD_SLEEP:
5153 			dev->flags |= ATA_DFLAG_SLEEPING;
5154 			break;
5155 		}
5156 
5157 		if (unlikely(dev->flags & ATA_DFLAG_DUBIOUS_XFER))
5158 			ata_verify_xfer(qc);
5159 
5160 		__ata_qc_complete(qc);
5161 	} else {
5162 		if (qc->flags & ATA_QCFLAG_EH_SCHEDULED)
5163 			return;
5164 
5165 		/* read result TF if failed or requested */
5166 		if (qc->err_mask || qc->flags & ATA_QCFLAG_RESULT_TF)
5167 			fill_result_tf(qc);
5168 
5169 		__ata_qc_complete(qc);
5170 	}
5171 }
5172 
5173 /**
5174  *	ata_qc_complete_multiple - Complete multiple qcs successfully
5175  *	@ap: port in question
5176  *	@qc_active: new qc_active mask
5177  *
5178  *	Complete in-flight commands.  This functions is meant to be
5179  *	called from low-level driver's interrupt routine to complete
5180  *	requests normally.  ap->qc_active and @qc_active is compared
5181  *	and commands are completed accordingly.
5182  *
5183  *	Always use this function when completing multiple NCQ commands
5184  *	from IRQ handlers instead of calling ata_qc_complete()
5185  *	multiple times to keep IRQ expect status properly in sync.
5186  *
5187  *	LOCKING:
5188  *	spin_lock_irqsave(host lock)
5189  *
5190  *	RETURNS:
5191  *	Number of completed commands on success, -errno otherwise.
5192  */
5193 int ata_qc_complete_multiple(struct ata_port *ap, u32 qc_active)
5194 {
5195 	int nr_done = 0;
5196 	u32 done_mask;
5197 
5198 	done_mask = ap->qc_active ^ qc_active;
5199 
5200 	if (unlikely(done_mask & qc_active)) {
5201 		ata_port_err(ap, "illegal qc_active transition (%08x->%08x)\n",
5202 			     ap->qc_active, qc_active);
5203 		return -EINVAL;
5204 	}
5205 
5206 	while (done_mask) {
5207 		struct ata_queued_cmd *qc;
5208 		unsigned int tag = __ffs(done_mask);
5209 
5210 		qc = ata_qc_from_tag(ap, tag);
5211 		if (qc) {
5212 			ata_qc_complete(qc);
5213 			nr_done++;
5214 		}
5215 		done_mask &= ~(1 << tag);
5216 	}
5217 
5218 	return nr_done;
5219 }
5220 
5221 /**
5222  *	ata_qc_issue - issue taskfile to device
5223  *	@qc: command to issue to device
5224  *
5225  *	Prepare an ATA command to submission to device.
5226  *	This includes mapping the data into a DMA-able
5227  *	area, filling in the S/G table, and finally
5228  *	writing the taskfile to hardware, starting the command.
5229  *
5230  *	LOCKING:
5231  *	spin_lock_irqsave(host lock)
5232  */
5233 void ata_qc_issue(struct ata_queued_cmd *qc)
5234 {
5235 	struct ata_port *ap = qc->ap;
5236 	struct ata_link *link = qc->dev->link;
5237 	u8 prot = qc->tf.protocol;
5238 
5239 	/* Make sure only one non-NCQ command is outstanding.  The
5240 	 * check is skipped for old EH because it reuses active qc to
5241 	 * request ATAPI sense.
5242 	 */
5243 	WARN_ON_ONCE(ap->ops->error_handler && ata_tag_valid(link->active_tag));
5244 
5245 	if (ata_is_ncq(prot)) {
5246 		WARN_ON_ONCE(link->sactive & (1 << qc->tag));
5247 
5248 		if (!link->sactive)
5249 			ap->nr_active_links++;
5250 		link->sactive |= 1 << qc->tag;
5251 	} else {
5252 		WARN_ON_ONCE(link->sactive);
5253 
5254 		ap->nr_active_links++;
5255 		link->active_tag = qc->tag;
5256 	}
5257 
5258 	qc->flags |= ATA_QCFLAG_ACTIVE;
5259 	ap->qc_active |= 1 << qc->tag;
5260 
5261 	/*
5262 	 * We guarantee to LLDs that they will have at least one
5263 	 * non-zero sg if the command is a data command.
5264 	 */
5265 	if (WARN_ON_ONCE(ata_is_data(prot) &&
5266 			 (!qc->sg || !qc->n_elem || !qc->nbytes)))
5267 		goto sys_err;
5268 
5269 	if (ata_is_dma(prot) || (ata_is_pio(prot) &&
5270 				 (ap->flags & ATA_FLAG_PIO_DMA)))
5271 		if (ata_sg_setup(qc))
5272 			goto sys_err;
5273 
5274 	/* if device is sleeping, schedule reset and abort the link */
5275 	if (unlikely(qc->dev->flags & ATA_DFLAG_SLEEPING)) {
5276 		link->eh_info.action |= ATA_EH_RESET;
5277 		ata_ehi_push_desc(&link->eh_info, "waking up from sleep");
5278 		ata_link_abort(link);
5279 		return;
5280 	}
5281 
5282 	ap->ops->qc_prep(qc);
5283 	trace_ata_qc_issue(qc);
5284 	qc->err_mask |= ap->ops->qc_issue(qc);
5285 	if (unlikely(qc->err_mask))
5286 		goto err;
5287 	return;
5288 
5289 sys_err:
5290 	qc->err_mask |= AC_ERR_SYSTEM;
5291 err:
5292 	ata_qc_complete(qc);
5293 }
5294 
5295 /**
5296  *	sata_scr_valid - test whether SCRs are accessible
5297  *	@link: ATA link to test SCR accessibility for
5298  *
5299  *	Test whether SCRs are accessible for @link.
5300  *
5301  *	LOCKING:
5302  *	None.
5303  *
5304  *	RETURNS:
5305  *	1 if SCRs are accessible, 0 otherwise.
5306  */
5307 int sata_scr_valid(struct ata_link *link)
5308 {
5309 	struct ata_port *ap = link->ap;
5310 
5311 	return (ap->flags & ATA_FLAG_SATA) && ap->ops->scr_read;
5312 }
5313 
5314 /**
5315  *	sata_scr_read - read SCR register of the specified port
5316  *	@link: ATA link to read SCR for
5317  *	@reg: SCR to read
5318  *	@val: Place to store read value
5319  *
5320  *	Read SCR register @reg of @link into *@val.  This function is
5321  *	guaranteed to succeed if @link is ap->link, the cable type of
5322  *	the port is SATA and the port implements ->scr_read.
5323  *
5324  *	LOCKING:
5325  *	None if @link is ap->link.  Kernel thread context otherwise.
5326  *
5327  *	RETURNS:
5328  *	0 on success, negative errno on failure.
5329  */
5330 int sata_scr_read(struct ata_link *link, int reg, u32 *val)
5331 {
5332 	if (ata_is_host_link(link)) {
5333 		if (sata_scr_valid(link))
5334 			return link->ap->ops->scr_read(link, reg, val);
5335 		return -EOPNOTSUPP;
5336 	}
5337 
5338 	return sata_pmp_scr_read(link, reg, val);
5339 }
5340 
5341 /**
5342  *	sata_scr_write - write SCR register of the specified port
5343  *	@link: ATA link to write SCR for
5344  *	@reg: SCR to write
5345  *	@val: value to write
5346  *
5347  *	Write @val to SCR register @reg of @link.  This function is
5348  *	guaranteed to succeed if @link is ap->link, the cable type of
5349  *	the port is SATA and the port implements ->scr_read.
5350  *
5351  *	LOCKING:
5352  *	None if @link is ap->link.  Kernel thread context otherwise.
5353  *
5354  *	RETURNS:
5355  *	0 on success, negative errno on failure.
5356  */
5357 int sata_scr_write(struct ata_link *link, int reg, u32 val)
5358 {
5359 	if (ata_is_host_link(link)) {
5360 		if (sata_scr_valid(link))
5361 			return link->ap->ops->scr_write(link, reg, val);
5362 		return -EOPNOTSUPP;
5363 	}
5364 
5365 	return sata_pmp_scr_write(link, reg, val);
5366 }
5367 
5368 /**
5369  *	sata_scr_write_flush - write SCR register of the specified port and flush
5370  *	@link: ATA link to write SCR for
5371  *	@reg: SCR to write
5372  *	@val: value to write
5373  *
5374  *	This function is identical to sata_scr_write() except that this
5375  *	function performs flush after writing to the register.
5376  *
5377  *	LOCKING:
5378  *	None if @link is ap->link.  Kernel thread context otherwise.
5379  *
5380  *	RETURNS:
5381  *	0 on success, negative errno on failure.
5382  */
5383 int sata_scr_write_flush(struct ata_link *link, int reg, u32 val)
5384 {
5385 	if (ata_is_host_link(link)) {
5386 		int rc;
5387 
5388 		if (sata_scr_valid(link)) {
5389 			rc = link->ap->ops->scr_write(link, reg, val);
5390 			if (rc == 0)
5391 				rc = link->ap->ops->scr_read(link, reg, &val);
5392 			return rc;
5393 		}
5394 		return -EOPNOTSUPP;
5395 	}
5396 
5397 	return sata_pmp_scr_write(link, reg, val);
5398 }
5399 
5400 /**
5401  *	ata_phys_link_online - test whether the given link is online
5402  *	@link: ATA link to test
5403  *
5404  *	Test whether @link is online.  Note that this function returns
5405  *	0 if online status of @link cannot be obtained, so
5406  *	ata_link_online(link) != !ata_link_offline(link).
5407  *
5408  *	LOCKING:
5409  *	None.
5410  *
5411  *	RETURNS:
5412  *	True if the port online status is available and online.
5413  */
5414 bool ata_phys_link_online(struct ata_link *link)
5415 {
5416 	u32 sstatus;
5417 
5418 	if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0 &&
5419 	    ata_sstatus_online(sstatus))
5420 		return true;
5421 	return false;
5422 }
5423 
5424 /**
5425  *	ata_phys_link_offline - test whether the given link is offline
5426  *	@link: ATA link to test
5427  *
5428  *	Test whether @link is offline.  Note that this function
5429  *	returns 0 if offline status of @link cannot be obtained, so
5430  *	ata_link_online(link) != !ata_link_offline(link).
5431  *
5432  *	LOCKING:
5433  *	None.
5434  *
5435  *	RETURNS:
5436  *	True if the port offline status is available and offline.
5437  */
5438 bool ata_phys_link_offline(struct ata_link *link)
5439 {
5440 	u32 sstatus;
5441 
5442 	if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0 &&
5443 	    !ata_sstatus_online(sstatus))
5444 		return true;
5445 	return false;
5446 }
5447 
5448 /**
5449  *	ata_link_online - test whether the given link is online
5450  *	@link: ATA link to test
5451  *
5452  *	Test whether @link is online.  This is identical to
5453  *	ata_phys_link_online() when there's no slave link.  When
5454  *	there's a slave link, this function should only be called on
5455  *	the master link and will return true if any of M/S links is
5456  *	online.
5457  *
5458  *	LOCKING:
5459  *	None.
5460  *
5461  *	RETURNS:
5462  *	True if the port online status is available and online.
5463  */
5464 bool ata_link_online(struct ata_link *link)
5465 {
5466 	struct ata_link *slave = link->ap->slave_link;
5467 
5468 	WARN_ON(link == slave);	/* shouldn't be called on slave link */
5469 
5470 	return ata_phys_link_online(link) ||
5471 		(slave && ata_phys_link_online(slave));
5472 }
5473 
5474 /**
5475  *	ata_link_offline - test whether the given link is offline
5476  *	@link: ATA link to test
5477  *
5478  *	Test whether @link is offline.  This is identical to
5479  *	ata_phys_link_offline() when there's no slave link.  When
5480  *	there's a slave link, this function should only be called on
5481  *	the master link and will return true if both M/S links are
5482  *	offline.
5483  *
5484  *	LOCKING:
5485  *	None.
5486  *
5487  *	RETURNS:
5488  *	True if the port offline status is available and offline.
5489  */
5490 bool ata_link_offline(struct ata_link *link)
5491 {
5492 	struct ata_link *slave = link->ap->slave_link;
5493 
5494 	WARN_ON(link == slave);	/* shouldn't be called on slave link */
5495 
5496 	return ata_phys_link_offline(link) &&
5497 		(!slave || ata_phys_link_offline(slave));
5498 }
5499 
5500 #ifdef CONFIG_PM
5501 static void ata_port_request_pm(struct ata_port *ap, pm_message_t mesg,
5502 				unsigned int action, unsigned int ehi_flags,
5503 				bool async)
5504 {
5505 	struct ata_link *link;
5506 	unsigned long flags;
5507 
5508 	/* Previous resume operation might still be in
5509 	 * progress.  Wait for PM_PENDING to clear.
5510 	 */
5511 	if (ap->pflags & ATA_PFLAG_PM_PENDING) {
5512 		ata_port_wait_eh(ap);
5513 		WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
5514 	}
5515 
5516 	/* request PM ops to EH */
5517 	spin_lock_irqsave(ap->lock, flags);
5518 
5519 	ap->pm_mesg = mesg;
5520 	ap->pflags |= ATA_PFLAG_PM_PENDING;
5521 	ata_for_each_link(link, ap, HOST_FIRST) {
5522 		link->eh_info.action |= action;
5523 		link->eh_info.flags |= ehi_flags;
5524 	}
5525 
5526 	ata_port_schedule_eh(ap);
5527 
5528 	spin_unlock_irqrestore(ap->lock, flags);
5529 
5530 	if (!async) {
5531 		ata_port_wait_eh(ap);
5532 		WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
5533 	}
5534 }
5535 
5536 /*
5537  * On some hardware, device fails to respond after spun down for suspend.  As
5538  * the device won't be used before being resumed, we don't need to touch the
5539  * device.  Ask EH to skip the usual stuff and proceed directly to suspend.
5540  *
5541  * http://thread.gmane.org/gmane.linux.ide/46764
5542  */
5543 static const unsigned int ata_port_suspend_ehi = ATA_EHI_QUIET
5544 						 | ATA_EHI_NO_AUTOPSY
5545 						 | ATA_EHI_NO_RECOVERY;
5546 
5547 static void ata_port_suspend(struct ata_port *ap, pm_message_t mesg)
5548 {
5549 	ata_port_request_pm(ap, mesg, 0, ata_port_suspend_ehi, false);
5550 }
5551 
5552 static void ata_port_suspend_async(struct ata_port *ap, pm_message_t mesg)
5553 {
5554 	ata_port_request_pm(ap, mesg, 0, ata_port_suspend_ehi, true);
5555 }
5556 
5557 static int ata_port_pm_suspend(struct device *dev)
5558 {
5559 	struct ata_port *ap = to_ata_port(dev);
5560 
5561 	if (pm_runtime_suspended(dev))
5562 		return 0;
5563 
5564 	ata_port_suspend(ap, PMSG_SUSPEND);
5565 	return 0;
5566 }
5567 
5568 static int ata_port_pm_freeze(struct device *dev)
5569 {
5570 	struct ata_port *ap = to_ata_port(dev);
5571 
5572 	if (pm_runtime_suspended(dev))
5573 		return 0;
5574 
5575 	ata_port_suspend(ap, PMSG_FREEZE);
5576 	return 0;
5577 }
5578 
5579 static int ata_port_pm_poweroff(struct device *dev)
5580 {
5581 	ata_port_suspend(to_ata_port(dev), PMSG_HIBERNATE);
5582 	return 0;
5583 }
5584 
5585 static const unsigned int ata_port_resume_ehi = ATA_EHI_NO_AUTOPSY
5586 						| ATA_EHI_QUIET;
5587 
5588 static void ata_port_resume(struct ata_port *ap, pm_message_t mesg)
5589 {
5590 	ata_port_request_pm(ap, mesg, ATA_EH_RESET, ata_port_resume_ehi, false);
5591 }
5592 
5593 static void ata_port_resume_async(struct ata_port *ap, pm_message_t mesg)
5594 {
5595 	ata_port_request_pm(ap, mesg, ATA_EH_RESET, ata_port_resume_ehi, true);
5596 }
5597 
5598 static int ata_port_pm_resume(struct device *dev)
5599 {
5600 	ata_port_resume_async(to_ata_port(dev), PMSG_RESUME);
5601 	pm_runtime_disable(dev);
5602 	pm_runtime_set_active(dev);
5603 	pm_runtime_enable(dev);
5604 	return 0;
5605 }
5606 
5607 /*
5608  * For ODDs, the upper layer will poll for media change every few seconds,
5609  * which will make it enter and leave suspend state every few seconds. And
5610  * as each suspend will cause a hard/soft reset, the gain of runtime suspend
5611  * is very little and the ODD may malfunction after constantly being reset.
5612  * So the idle callback here will not proceed to suspend if a non-ZPODD capable
5613  * ODD is attached to the port.
5614  */
5615 static int ata_port_runtime_idle(struct device *dev)
5616 {
5617 	struct ata_port *ap = to_ata_port(dev);
5618 	struct ata_link *link;
5619 	struct ata_device *adev;
5620 
5621 	ata_for_each_link(link, ap, HOST_FIRST) {
5622 		ata_for_each_dev(adev, link, ENABLED)
5623 			if (adev->class == ATA_DEV_ATAPI &&
5624 			    !zpodd_dev_enabled(adev))
5625 				return -EBUSY;
5626 	}
5627 
5628 	return 0;
5629 }
5630 
5631 static int ata_port_runtime_suspend(struct device *dev)
5632 {
5633 	ata_port_suspend(to_ata_port(dev), PMSG_AUTO_SUSPEND);
5634 	return 0;
5635 }
5636 
5637 static int ata_port_runtime_resume(struct device *dev)
5638 {
5639 	ata_port_resume(to_ata_port(dev), PMSG_AUTO_RESUME);
5640 	return 0;
5641 }
5642 
5643 static const struct dev_pm_ops ata_port_pm_ops = {
5644 	.suspend = ata_port_pm_suspend,
5645 	.resume = ata_port_pm_resume,
5646 	.freeze = ata_port_pm_freeze,
5647 	.thaw = ata_port_pm_resume,
5648 	.poweroff = ata_port_pm_poweroff,
5649 	.restore = ata_port_pm_resume,
5650 
5651 	.runtime_suspend = ata_port_runtime_suspend,
5652 	.runtime_resume = ata_port_runtime_resume,
5653 	.runtime_idle = ata_port_runtime_idle,
5654 };
5655 
5656 /* sas ports don't participate in pm runtime management of ata_ports,
5657  * and need to resume ata devices at the domain level, not the per-port
5658  * level. sas suspend/resume is async to allow parallel port recovery
5659  * since sas has multiple ata_port instances per Scsi_Host.
5660  */
5661 void ata_sas_port_suspend(struct ata_port *ap)
5662 {
5663 	ata_port_suspend_async(ap, PMSG_SUSPEND);
5664 }
5665 EXPORT_SYMBOL_GPL(ata_sas_port_suspend);
5666 
5667 void ata_sas_port_resume(struct ata_port *ap)
5668 {
5669 	ata_port_resume_async(ap, PMSG_RESUME);
5670 }
5671 EXPORT_SYMBOL_GPL(ata_sas_port_resume);
5672 
5673 /**
5674  *	ata_host_suspend - suspend host
5675  *	@host: host to suspend
5676  *	@mesg: PM message
5677  *
5678  *	Suspend @host.  Actual operation is performed by port suspend.
5679  */
5680 int ata_host_suspend(struct ata_host *host, pm_message_t mesg)
5681 {
5682 	host->dev->power.power_state = mesg;
5683 	return 0;
5684 }
5685 
5686 /**
5687  *	ata_host_resume - resume host
5688  *	@host: host to resume
5689  *
5690  *	Resume @host.  Actual operation is performed by port resume.
5691  */
5692 void ata_host_resume(struct ata_host *host)
5693 {
5694 	host->dev->power.power_state = PMSG_ON;
5695 }
5696 #endif
5697 
5698 struct device_type ata_port_type = {
5699 	.name = "ata_port",
5700 #ifdef CONFIG_PM
5701 	.pm = &ata_port_pm_ops,
5702 #endif
5703 };
5704 
5705 /**
5706  *	ata_dev_init - Initialize an ata_device structure
5707  *	@dev: Device structure to initialize
5708  *
5709  *	Initialize @dev in preparation for probing.
5710  *
5711  *	LOCKING:
5712  *	Inherited from caller.
5713  */
5714 void ata_dev_init(struct ata_device *dev)
5715 {
5716 	struct ata_link *link = ata_dev_phys_link(dev);
5717 	struct ata_port *ap = link->ap;
5718 	unsigned long flags;
5719 
5720 	/* SATA spd limit is bound to the attached device, reset together */
5721 	link->sata_spd_limit = link->hw_sata_spd_limit;
5722 	link->sata_spd = 0;
5723 
5724 	/* High bits of dev->flags are used to record warm plug
5725 	 * requests which occur asynchronously.  Synchronize using
5726 	 * host lock.
5727 	 */
5728 	spin_lock_irqsave(ap->lock, flags);
5729 	dev->flags &= ~ATA_DFLAG_INIT_MASK;
5730 	dev->horkage = 0;
5731 	spin_unlock_irqrestore(ap->lock, flags);
5732 
5733 	memset((void *)dev + ATA_DEVICE_CLEAR_BEGIN, 0,
5734 	       ATA_DEVICE_CLEAR_END - ATA_DEVICE_CLEAR_BEGIN);
5735 	dev->pio_mask = UINT_MAX;
5736 	dev->mwdma_mask = UINT_MAX;
5737 	dev->udma_mask = UINT_MAX;
5738 }
5739 
5740 /**
5741  *	ata_link_init - Initialize an ata_link structure
5742  *	@ap: ATA port link is attached to
5743  *	@link: Link structure to initialize
5744  *	@pmp: Port multiplier port number
5745  *
5746  *	Initialize @link.
5747  *
5748  *	LOCKING:
5749  *	Kernel thread context (may sleep)
5750  */
5751 void ata_link_init(struct ata_port *ap, struct ata_link *link, int pmp)
5752 {
5753 	int i;
5754 
5755 	/* clear everything except for devices */
5756 	memset((void *)link + ATA_LINK_CLEAR_BEGIN, 0,
5757 	       ATA_LINK_CLEAR_END - ATA_LINK_CLEAR_BEGIN);
5758 
5759 	link->ap = ap;
5760 	link->pmp = pmp;
5761 	link->active_tag = ATA_TAG_POISON;
5762 	link->hw_sata_spd_limit = UINT_MAX;
5763 
5764 	/* can't use iterator, ap isn't initialized yet */
5765 	for (i = 0; i < ATA_MAX_DEVICES; i++) {
5766 		struct ata_device *dev = &link->device[i];
5767 
5768 		dev->link = link;
5769 		dev->devno = dev - link->device;
5770 #ifdef CONFIG_ATA_ACPI
5771 		dev->gtf_filter = ata_acpi_gtf_filter;
5772 #endif
5773 		ata_dev_init(dev);
5774 	}
5775 }
5776 
5777 /**
5778  *	sata_link_init_spd - Initialize link->sata_spd_limit
5779  *	@link: Link to configure sata_spd_limit for
5780  *
5781  *	Initialize @link->[hw_]sata_spd_limit to the currently
5782  *	configured value.
5783  *
5784  *	LOCKING:
5785  *	Kernel thread context (may sleep).
5786  *
5787  *	RETURNS:
5788  *	0 on success, -errno on failure.
5789  */
5790 int sata_link_init_spd(struct ata_link *link)
5791 {
5792 	u8 spd;
5793 	int rc;
5794 
5795 	rc = sata_scr_read(link, SCR_CONTROL, &link->saved_scontrol);
5796 	if (rc)
5797 		return rc;
5798 
5799 	spd = (link->saved_scontrol >> 4) & 0xf;
5800 	if (spd)
5801 		link->hw_sata_spd_limit &= (1 << spd) - 1;
5802 
5803 	ata_force_link_limits(link);
5804 
5805 	link->sata_spd_limit = link->hw_sata_spd_limit;
5806 
5807 	return 0;
5808 }
5809 
5810 /**
5811  *	ata_port_alloc - allocate and initialize basic ATA port resources
5812  *	@host: ATA host this allocated port belongs to
5813  *
5814  *	Allocate and initialize basic ATA port resources.
5815  *
5816  *	RETURNS:
5817  *	Allocate ATA port on success, NULL on failure.
5818  *
5819  *	LOCKING:
5820  *	Inherited from calling layer (may sleep).
5821  */
5822 struct ata_port *ata_port_alloc(struct ata_host *host)
5823 {
5824 	struct ata_port *ap;
5825 
5826 	DPRINTK("ENTER\n");
5827 
5828 	ap = kzalloc(sizeof(*ap), GFP_KERNEL);
5829 	if (!ap)
5830 		return NULL;
5831 
5832 	ap->pflags |= ATA_PFLAG_INITIALIZING | ATA_PFLAG_FROZEN;
5833 	ap->lock = &host->lock;
5834 	ap->print_id = -1;
5835 	ap->local_port_no = -1;
5836 	ap->host = host;
5837 	ap->dev = host->dev;
5838 
5839 #if defined(ATA_VERBOSE_DEBUG)
5840 	/* turn on all debugging levels */
5841 	ap->msg_enable = 0x00FF;
5842 #elif defined(ATA_DEBUG)
5843 	ap->msg_enable = ATA_MSG_DRV | ATA_MSG_INFO | ATA_MSG_CTL | ATA_MSG_WARN | ATA_MSG_ERR;
5844 #else
5845 	ap->msg_enable = ATA_MSG_DRV | ATA_MSG_ERR | ATA_MSG_WARN;
5846 #endif
5847 
5848 	mutex_init(&ap->scsi_scan_mutex);
5849 	INIT_DELAYED_WORK(&ap->hotplug_task, ata_scsi_hotplug);
5850 	INIT_WORK(&ap->scsi_rescan_task, ata_scsi_dev_rescan);
5851 	INIT_LIST_HEAD(&ap->eh_done_q);
5852 	init_waitqueue_head(&ap->eh_wait_q);
5853 	init_completion(&ap->park_req_pending);
5854 	init_timer_deferrable(&ap->fastdrain_timer);
5855 	ap->fastdrain_timer.function = ata_eh_fastdrain_timerfn;
5856 	ap->fastdrain_timer.data = (unsigned long)ap;
5857 
5858 	ap->cbl = ATA_CBL_NONE;
5859 
5860 	ata_link_init(ap, &ap->link, 0);
5861 
5862 #ifdef ATA_IRQ_TRAP
5863 	ap->stats.unhandled_irq = 1;
5864 	ap->stats.idle_irq = 1;
5865 #endif
5866 	ata_sff_port_init(ap);
5867 
5868 	return ap;
5869 }
5870 
5871 static void ata_host_release(struct device *gendev, void *res)
5872 {
5873 	struct ata_host *host = dev_get_drvdata(gendev);
5874 	int i;
5875 
5876 	for (i = 0; i < host->n_ports; i++) {
5877 		struct ata_port *ap = host->ports[i];
5878 
5879 		if (!ap)
5880 			continue;
5881 
5882 		if (ap->scsi_host)
5883 			scsi_host_put(ap->scsi_host);
5884 
5885 		kfree(ap->pmp_link);
5886 		kfree(ap->slave_link);
5887 		kfree(ap);
5888 		host->ports[i] = NULL;
5889 	}
5890 
5891 	dev_set_drvdata(gendev, NULL);
5892 }
5893 
5894 /**
5895  *	ata_host_alloc - allocate and init basic ATA host resources
5896  *	@dev: generic device this host is associated with
5897  *	@max_ports: maximum number of ATA ports associated with this host
5898  *
5899  *	Allocate and initialize basic ATA host resources.  LLD calls
5900  *	this function to allocate a host, initializes it fully and
5901  *	attaches it using ata_host_register().
5902  *
5903  *	@max_ports ports are allocated and host->n_ports is
5904  *	initialized to @max_ports.  The caller is allowed to decrease
5905  *	host->n_ports before calling ata_host_register().  The unused
5906  *	ports will be automatically freed on registration.
5907  *
5908  *	RETURNS:
5909  *	Allocate ATA host on success, NULL on failure.
5910  *
5911  *	LOCKING:
5912  *	Inherited from calling layer (may sleep).
5913  */
5914 struct ata_host *ata_host_alloc(struct device *dev, int max_ports)
5915 {
5916 	struct ata_host *host;
5917 	size_t sz;
5918 	int i;
5919 
5920 	DPRINTK("ENTER\n");
5921 
5922 	if (!devres_open_group(dev, NULL, GFP_KERNEL))
5923 		return NULL;
5924 
5925 	/* alloc a container for our list of ATA ports (buses) */
5926 	sz = sizeof(struct ata_host) + (max_ports + 1) * sizeof(void *);
5927 	/* alloc a container for our list of ATA ports (buses) */
5928 	host = devres_alloc(ata_host_release, sz, GFP_KERNEL);
5929 	if (!host)
5930 		goto err_out;
5931 
5932 	devres_add(dev, host);
5933 	dev_set_drvdata(dev, host);
5934 
5935 	spin_lock_init(&host->lock);
5936 	mutex_init(&host->eh_mutex);
5937 	host->dev = dev;
5938 	host->n_ports = max_ports;
5939 
5940 	/* allocate ports bound to this host */
5941 	for (i = 0; i < max_ports; i++) {
5942 		struct ata_port *ap;
5943 
5944 		ap = ata_port_alloc(host);
5945 		if (!ap)
5946 			goto err_out;
5947 
5948 		ap->port_no = i;
5949 		host->ports[i] = ap;
5950 	}
5951 
5952 	devres_remove_group(dev, NULL);
5953 	return host;
5954 
5955  err_out:
5956 	devres_release_group(dev, NULL);
5957 	return NULL;
5958 }
5959 
5960 /**
5961  *	ata_host_alloc_pinfo - alloc host and init with port_info array
5962  *	@dev: generic device this host is associated with
5963  *	@ppi: array of ATA port_info to initialize host with
5964  *	@n_ports: number of ATA ports attached to this host
5965  *
5966  *	Allocate ATA host and initialize with info from @ppi.  If NULL
5967  *	terminated, @ppi may contain fewer entries than @n_ports.  The
5968  *	last entry will be used for the remaining ports.
5969  *
5970  *	RETURNS:
5971  *	Allocate ATA host on success, NULL on failure.
5972  *
5973  *	LOCKING:
5974  *	Inherited from calling layer (may sleep).
5975  */
5976 struct ata_host *ata_host_alloc_pinfo(struct device *dev,
5977 				      const struct ata_port_info * const * ppi,
5978 				      int n_ports)
5979 {
5980 	const struct ata_port_info *pi;
5981 	struct ata_host *host;
5982 	int i, j;
5983 
5984 	host = ata_host_alloc(dev, n_ports);
5985 	if (!host)
5986 		return NULL;
5987 
5988 	for (i = 0, j = 0, pi = NULL; i < host->n_ports; i++) {
5989 		struct ata_port *ap = host->ports[i];
5990 
5991 		if (ppi[j])
5992 			pi = ppi[j++];
5993 
5994 		ap->pio_mask = pi->pio_mask;
5995 		ap->mwdma_mask = pi->mwdma_mask;
5996 		ap->udma_mask = pi->udma_mask;
5997 		ap->flags |= pi->flags;
5998 		ap->link.flags |= pi->link_flags;
5999 		ap->ops = pi->port_ops;
6000 
6001 		if (!host->ops && (pi->port_ops != &ata_dummy_port_ops))
6002 			host->ops = pi->port_ops;
6003 	}
6004 
6005 	return host;
6006 }
6007 
6008 /**
6009  *	ata_slave_link_init - initialize slave link
6010  *	@ap: port to initialize slave link for
6011  *
6012  *	Create and initialize slave link for @ap.  This enables slave
6013  *	link handling on the port.
6014  *
6015  *	In libata, a port contains links and a link contains devices.
6016  *	There is single host link but if a PMP is attached to it,
6017  *	there can be multiple fan-out links.  On SATA, there's usually
6018  *	a single device connected to a link but PATA and SATA
6019  *	controllers emulating TF based interface can have two - master
6020  *	and slave.
6021  *
6022  *	However, there are a few controllers which don't fit into this
6023  *	abstraction too well - SATA controllers which emulate TF
6024  *	interface with both master and slave devices but also have
6025  *	separate SCR register sets for each device.  These controllers
6026  *	need separate links for physical link handling
6027  *	(e.g. onlineness, link speed) but should be treated like a
6028  *	traditional M/S controller for everything else (e.g. command
6029  *	issue, softreset).
6030  *
6031  *	slave_link is libata's way of handling this class of
6032  *	controllers without impacting core layer too much.  For
6033  *	anything other than physical link handling, the default host
6034  *	link is used for both master and slave.  For physical link
6035  *	handling, separate @ap->slave_link is used.  All dirty details
6036  *	are implemented inside libata core layer.  From LLD's POV, the
6037  *	only difference is that prereset, hardreset and postreset are
6038  *	called once more for the slave link, so the reset sequence
6039  *	looks like the following.
6040  *
6041  *	prereset(M) -> prereset(S) -> hardreset(M) -> hardreset(S) ->
6042  *	softreset(M) -> postreset(M) -> postreset(S)
6043  *
6044  *	Note that softreset is called only for the master.  Softreset
6045  *	resets both M/S by definition, so SRST on master should handle
6046  *	both (the standard method will work just fine).
6047  *
6048  *	LOCKING:
6049  *	Should be called before host is registered.
6050  *
6051  *	RETURNS:
6052  *	0 on success, -errno on failure.
6053  */
6054 int ata_slave_link_init(struct ata_port *ap)
6055 {
6056 	struct ata_link *link;
6057 
6058 	WARN_ON(ap->slave_link);
6059 	WARN_ON(ap->flags & ATA_FLAG_PMP);
6060 
6061 	link = kzalloc(sizeof(*link), GFP_KERNEL);
6062 	if (!link)
6063 		return -ENOMEM;
6064 
6065 	ata_link_init(ap, link, 1);
6066 	ap->slave_link = link;
6067 	return 0;
6068 }
6069 
6070 static void ata_host_stop(struct device *gendev, void *res)
6071 {
6072 	struct ata_host *host = dev_get_drvdata(gendev);
6073 	int i;
6074 
6075 	WARN_ON(!(host->flags & ATA_HOST_STARTED));
6076 
6077 	for (i = 0; i < host->n_ports; i++) {
6078 		struct ata_port *ap = host->ports[i];
6079 
6080 		if (ap->ops->port_stop)
6081 			ap->ops->port_stop(ap);
6082 	}
6083 
6084 	if (host->ops->host_stop)
6085 		host->ops->host_stop(host);
6086 }
6087 
6088 /**
6089  *	ata_finalize_port_ops - finalize ata_port_operations
6090  *	@ops: ata_port_operations to finalize
6091  *
6092  *	An ata_port_operations can inherit from another ops and that
6093  *	ops can again inherit from another.  This can go on as many
6094  *	times as necessary as long as there is no loop in the
6095  *	inheritance chain.
6096  *
6097  *	Ops tables are finalized when the host is started.  NULL or
6098  *	unspecified entries are inherited from the closet ancestor
6099  *	which has the method and the entry is populated with it.
6100  *	After finalization, the ops table directly points to all the
6101  *	methods and ->inherits is no longer necessary and cleared.
6102  *
6103  *	Using ATA_OP_NULL, inheriting ops can force a method to NULL.
6104  *
6105  *	LOCKING:
6106  *	None.
6107  */
6108 static void ata_finalize_port_ops(struct ata_port_operations *ops)
6109 {
6110 	static DEFINE_SPINLOCK(lock);
6111 	const struct ata_port_operations *cur;
6112 	void **begin = (void **)ops;
6113 	void **end = (void **)&ops->inherits;
6114 	void **pp;
6115 
6116 	if (!ops || !ops->inherits)
6117 		return;
6118 
6119 	spin_lock(&lock);
6120 
6121 	for (cur = ops->inherits; cur; cur = cur->inherits) {
6122 		void **inherit = (void **)cur;
6123 
6124 		for (pp = begin; pp < end; pp++, inherit++)
6125 			if (!*pp)
6126 				*pp = *inherit;
6127 	}
6128 
6129 	for (pp = begin; pp < end; pp++)
6130 		if (IS_ERR(*pp))
6131 			*pp = NULL;
6132 
6133 	ops->inherits = NULL;
6134 
6135 	spin_unlock(&lock);
6136 }
6137 
6138 /**
6139  *	ata_host_start - start and freeze ports of an ATA host
6140  *	@host: ATA host to start ports for
6141  *
6142  *	Start and then freeze ports of @host.  Started status is
6143  *	recorded in host->flags, so this function can be called
6144  *	multiple times.  Ports are guaranteed to get started only
6145  *	once.  If host->ops isn't initialized yet, its set to the
6146  *	first non-dummy port ops.
6147  *
6148  *	LOCKING:
6149  *	Inherited from calling layer (may sleep).
6150  *
6151  *	RETURNS:
6152  *	0 if all ports are started successfully, -errno otherwise.
6153  */
6154 int ata_host_start(struct ata_host *host)
6155 {
6156 	int have_stop = 0;
6157 	void *start_dr = NULL;
6158 	int i, rc;
6159 
6160 	if (host->flags & ATA_HOST_STARTED)
6161 		return 0;
6162 
6163 	ata_finalize_port_ops(host->ops);
6164 
6165 	for (i = 0; i < host->n_ports; i++) {
6166 		struct ata_port *ap = host->ports[i];
6167 
6168 		ata_finalize_port_ops(ap->ops);
6169 
6170 		if (!host->ops && !ata_port_is_dummy(ap))
6171 			host->ops = ap->ops;
6172 
6173 		if (ap->ops->port_stop)
6174 			have_stop = 1;
6175 	}
6176 
6177 	if (host->ops->host_stop)
6178 		have_stop = 1;
6179 
6180 	if (have_stop) {
6181 		start_dr = devres_alloc(ata_host_stop, 0, GFP_KERNEL);
6182 		if (!start_dr)
6183 			return -ENOMEM;
6184 	}
6185 
6186 	for (i = 0; i < host->n_ports; i++) {
6187 		struct ata_port *ap = host->ports[i];
6188 
6189 		if (ap->ops->port_start) {
6190 			rc = ap->ops->port_start(ap);
6191 			if (rc) {
6192 				if (rc != -ENODEV)
6193 					dev_err(host->dev,
6194 						"failed to start port %d (errno=%d)\n",
6195 						i, rc);
6196 				goto err_out;
6197 			}
6198 		}
6199 		ata_eh_freeze_port(ap);
6200 	}
6201 
6202 	if (start_dr)
6203 		devres_add(host->dev, start_dr);
6204 	host->flags |= ATA_HOST_STARTED;
6205 	return 0;
6206 
6207  err_out:
6208 	while (--i >= 0) {
6209 		struct ata_port *ap = host->ports[i];
6210 
6211 		if (ap->ops->port_stop)
6212 			ap->ops->port_stop(ap);
6213 	}
6214 	devres_free(start_dr);
6215 	return rc;
6216 }
6217 
6218 /**
6219  *	ata_sas_host_init - Initialize a host struct for sas (ipr, libsas)
6220  *	@host:	host to initialize
6221  *	@dev:	device host is attached to
6222  *	@ops:	port_ops
6223  *
6224  */
6225 void ata_host_init(struct ata_host *host, struct device *dev,
6226 		   struct ata_port_operations *ops)
6227 {
6228 	spin_lock_init(&host->lock);
6229 	mutex_init(&host->eh_mutex);
6230 	host->n_tags = ATA_MAX_QUEUE - 1;
6231 	host->dev = dev;
6232 	host->ops = ops;
6233 }
6234 
6235 void __ata_port_probe(struct ata_port *ap)
6236 {
6237 	struct ata_eh_info *ehi = &ap->link.eh_info;
6238 	unsigned long flags;
6239 
6240 	/* kick EH for boot probing */
6241 	spin_lock_irqsave(ap->lock, flags);
6242 
6243 	ehi->probe_mask |= ATA_ALL_DEVICES;
6244 	ehi->action |= ATA_EH_RESET;
6245 	ehi->flags |= ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET;
6246 
6247 	ap->pflags &= ~ATA_PFLAG_INITIALIZING;
6248 	ap->pflags |= ATA_PFLAG_LOADING;
6249 	ata_port_schedule_eh(ap);
6250 
6251 	spin_unlock_irqrestore(ap->lock, flags);
6252 }
6253 
6254 int ata_port_probe(struct ata_port *ap)
6255 {
6256 	int rc = 0;
6257 
6258 	if (ap->ops->error_handler) {
6259 		__ata_port_probe(ap);
6260 		ata_port_wait_eh(ap);
6261 	} else {
6262 		DPRINTK("ata%u: bus probe begin\n", ap->print_id);
6263 		rc = ata_bus_probe(ap);
6264 		DPRINTK("ata%u: bus probe end\n", ap->print_id);
6265 	}
6266 	return rc;
6267 }
6268 
6269 
6270 static void async_port_probe(void *data, async_cookie_t cookie)
6271 {
6272 	struct ata_port *ap = data;
6273 
6274 	/*
6275 	 * If we're not allowed to scan this host in parallel,
6276 	 * we need to wait until all previous scans have completed
6277 	 * before going further.
6278 	 * Jeff Garzik says this is only within a controller, so we
6279 	 * don't need to wait for port 0, only for later ports.
6280 	 */
6281 	if (!(ap->host->flags & ATA_HOST_PARALLEL_SCAN) && ap->port_no != 0)
6282 		async_synchronize_cookie(cookie);
6283 
6284 	(void)ata_port_probe(ap);
6285 
6286 	/* in order to keep device order, we need to synchronize at this point */
6287 	async_synchronize_cookie(cookie);
6288 
6289 	ata_scsi_scan_host(ap, 1);
6290 }
6291 
6292 /**
6293  *	ata_host_register - register initialized ATA host
6294  *	@host: ATA host to register
6295  *	@sht: template for SCSI host
6296  *
6297  *	Register initialized ATA host.  @host is allocated using
6298  *	ata_host_alloc() and fully initialized by LLD.  This function
6299  *	starts ports, registers @host with ATA and SCSI layers and
6300  *	probe registered devices.
6301  *
6302  *	LOCKING:
6303  *	Inherited from calling layer (may sleep).
6304  *
6305  *	RETURNS:
6306  *	0 on success, -errno otherwise.
6307  */
6308 int ata_host_register(struct ata_host *host, struct scsi_host_template *sht)
6309 {
6310 	int i, rc;
6311 
6312 	host->n_tags = clamp(sht->can_queue, 1, ATA_MAX_QUEUE - 1);
6313 
6314 	/* host must have been started */
6315 	if (!(host->flags & ATA_HOST_STARTED)) {
6316 		dev_err(host->dev, "BUG: trying to register unstarted host\n");
6317 		WARN_ON(1);
6318 		return -EINVAL;
6319 	}
6320 
6321 	/* Blow away unused ports.  This happens when LLD can't
6322 	 * determine the exact number of ports to allocate at
6323 	 * allocation time.
6324 	 */
6325 	for (i = host->n_ports; host->ports[i]; i++)
6326 		kfree(host->ports[i]);
6327 
6328 	/* give ports names and add SCSI hosts */
6329 	for (i = 0; i < host->n_ports; i++) {
6330 		host->ports[i]->print_id = atomic_inc_return(&ata_print_id);
6331 		host->ports[i]->local_port_no = i + 1;
6332 	}
6333 
6334 	/* Create associated sysfs transport objects  */
6335 	for (i = 0; i < host->n_ports; i++) {
6336 		rc = ata_tport_add(host->dev,host->ports[i]);
6337 		if (rc) {
6338 			goto err_tadd;
6339 		}
6340 	}
6341 
6342 	rc = ata_scsi_add_hosts(host, sht);
6343 	if (rc)
6344 		goto err_tadd;
6345 
6346 	/* set cable, sata_spd_limit and report */
6347 	for (i = 0; i < host->n_ports; i++) {
6348 		struct ata_port *ap = host->ports[i];
6349 		unsigned long xfer_mask;
6350 
6351 		/* set SATA cable type if still unset */
6352 		if (ap->cbl == ATA_CBL_NONE && (ap->flags & ATA_FLAG_SATA))
6353 			ap->cbl = ATA_CBL_SATA;
6354 
6355 		/* init sata_spd_limit to the current value */
6356 		sata_link_init_spd(&ap->link);
6357 		if (ap->slave_link)
6358 			sata_link_init_spd(ap->slave_link);
6359 
6360 		/* print per-port info to dmesg */
6361 		xfer_mask = ata_pack_xfermask(ap->pio_mask, ap->mwdma_mask,
6362 					      ap->udma_mask);
6363 
6364 		if (!ata_port_is_dummy(ap)) {
6365 			ata_port_info(ap, "%cATA max %s %s\n",
6366 				      (ap->flags & ATA_FLAG_SATA) ? 'S' : 'P',
6367 				      ata_mode_string(xfer_mask),
6368 				      ap->link.eh_info.desc);
6369 			ata_ehi_clear_desc(&ap->link.eh_info);
6370 		} else
6371 			ata_port_info(ap, "DUMMY\n");
6372 	}
6373 
6374 	/* perform each probe asynchronously */
6375 	for (i = 0; i < host->n_ports; i++) {
6376 		struct ata_port *ap = host->ports[i];
6377 		async_schedule(async_port_probe, ap);
6378 	}
6379 
6380 	return 0;
6381 
6382  err_tadd:
6383 	while (--i >= 0) {
6384 		ata_tport_delete(host->ports[i]);
6385 	}
6386 	return rc;
6387 
6388 }
6389 
6390 /**
6391  *	ata_host_activate - start host, request IRQ and register it
6392  *	@host: target ATA host
6393  *	@irq: IRQ to request
6394  *	@irq_handler: irq_handler used when requesting IRQ
6395  *	@irq_flags: irq_flags used when requesting IRQ
6396  *	@sht: scsi_host_template to use when registering the host
6397  *
6398  *	After allocating an ATA host and initializing it, most libata
6399  *	LLDs perform three steps to activate the host - start host,
6400  *	request IRQ and register it.  This helper takes necessary
6401  *	arguments and performs the three steps in one go.
6402  *
6403  *	An invalid IRQ skips the IRQ registration and expects the host to
6404  *	have set polling mode on the port. In this case, @irq_handler
6405  *	should be NULL.
6406  *
6407  *	LOCKING:
6408  *	Inherited from calling layer (may sleep).
6409  *
6410  *	RETURNS:
6411  *	0 on success, -errno otherwise.
6412  */
6413 int ata_host_activate(struct ata_host *host, int irq,
6414 		      irq_handler_t irq_handler, unsigned long irq_flags,
6415 		      struct scsi_host_template *sht)
6416 {
6417 	int i, rc;
6418 	char *irq_desc;
6419 
6420 	rc = ata_host_start(host);
6421 	if (rc)
6422 		return rc;
6423 
6424 	/* Special case for polling mode */
6425 	if (!irq) {
6426 		WARN_ON(irq_handler);
6427 		return ata_host_register(host, sht);
6428 	}
6429 
6430 	irq_desc = devm_kasprintf(host->dev, GFP_KERNEL, "%s[%s]",
6431 				  dev_driver_string(host->dev),
6432 				  dev_name(host->dev));
6433 	if (!irq_desc)
6434 		return -ENOMEM;
6435 
6436 	rc = devm_request_irq(host->dev, irq, irq_handler, irq_flags,
6437 			      irq_desc, host);
6438 	if (rc)
6439 		return rc;
6440 
6441 	for (i = 0; i < host->n_ports; i++)
6442 		ata_port_desc(host->ports[i], "irq %d", irq);
6443 
6444 	rc = ata_host_register(host, sht);
6445 	/* if failed, just free the IRQ and leave ports alone */
6446 	if (rc)
6447 		devm_free_irq(host->dev, irq, host);
6448 
6449 	return rc;
6450 }
6451 
6452 /**
6453  *	ata_port_detach - Detach ATA port in preparation of device removal
6454  *	@ap: ATA port to be detached
6455  *
6456  *	Detach all ATA devices and the associated SCSI devices of @ap;
6457  *	then, remove the associated SCSI host.  @ap is guaranteed to
6458  *	be quiescent on return from this function.
6459  *
6460  *	LOCKING:
6461  *	Kernel thread context (may sleep).
6462  */
6463 static void ata_port_detach(struct ata_port *ap)
6464 {
6465 	unsigned long flags;
6466 	struct ata_link *link;
6467 	struct ata_device *dev;
6468 
6469 	if (!ap->ops->error_handler)
6470 		goto skip_eh;
6471 
6472 	/* tell EH we're leaving & flush EH */
6473 	spin_lock_irqsave(ap->lock, flags);
6474 	ap->pflags |= ATA_PFLAG_UNLOADING;
6475 	ata_port_schedule_eh(ap);
6476 	spin_unlock_irqrestore(ap->lock, flags);
6477 
6478 	/* wait till EH commits suicide */
6479 	ata_port_wait_eh(ap);
6480 
6481 	/* it better be dead now */
6482 	WARN_ON(!(ap->pflags & ATA_PFLAG_UNLOADED));
6483 
6484 	cancel_delayed_work_sync(&ap->hotplug_task);
6485 
6486  skip_eh:
6487 	/* clean up zpodd on port removal */
6488 	ata_for_each_link(link, ap, HOST_FIRST) {
6489 		ata_for_each_dev(dev, link, ALL) {
6490 			if (zpodd_dev_enabled(dev))
6491 				zpodd_exit(dev);
6492 		}
6493 	}
6494 	if (ap->pmp_link) {
6495 		int i;
6496 		for (i = 0; i < SATA_PMP_MAX_PORTS; i++)
6497 			ata_tlink_delete(&ap->pmp_link[i]);
6498 	}
6499 	/* remove the associated SCSI host */
6500 	scsi_remove_host(ap->scsi_host);
6501 	ata_tport_delete(ap);
6502 }
6503 
6504 /**
6505  *	ata_host_detach - Detach all ports of an ATA host
6506  *	@host: Host to detach
6507  *
6508  *	Detach all ports of @host.
6509  *
6510  *	LOCKING:
6511  *	Kernel thread context (may sleep).
6512  */
6513 void ata_host_detach(struct ata_host *host)
6514 {
6515 	int i;
6516 
6517 	for (i = 0; i < host->n_ports; i++)
6518 		ata_port_detach(host->ports[i]);
6519 
6520 	/* the host is dead now, dissociate ACPI */
6521 	ata_acpi_dissociate(host);
6522 }
6523 
6524 #ifdef CONFIG_PCI
6525 
6526 /**
6527  *	ata_pci_remove_one - PCI layer callback for device removal
6528  *	@pdev: PCI device that was removed
6529  *
6530  *	PCI layer indicates to libata via this hook that hot-unplug or
6531  *	module unload event has occurred.  Detach all ports.  Resource
6532  *	release is handled via devres.
6533  *
6534  *	LOCKING:
6535  *	Inherited from PCI layer (may sleep).
6536  */
6537 void ata_pci_remove_one(struct pci_dev *pdev)
6538 {
6539 	struct ata_host *host = pci_get_drvdata(pdev);
6540 
6541 	ata_host_detach(host);
6542 }
6543 
6544 /* move to PCI subsystem */
6545 int pci_test_config_bits(struct pci_dev *pdev, const struct pci_bits *bits)
6546 {
6547 	unsigned long tmp = 0;
6548 
6549 	switch (bits->width) {
6550 	case 1: {
6551 		u8 tmp8 = 0;
6552 		pci_read_config_byte(pdev, bits->reg, &tmp8);
6553 		tmp = tmp8;
6554 		break;
6555 	}
6556 	case 2: {
6557 		u16 tmp16 = 0;
6558 		pci_read_config_word(pdev, bits->reg, &tmp16);
6559 		tmp = tmp16;
6560 		break;
6561 	}
6562 	case 4: {
6563 		u32 tmp32 = 0;
6564 		pci_read_config_dword(pdev, bits->reg, &tmp32);
6565 		tmp = tmp32;
6566 		break;
6567 	}
6568 
6569 	default:
6570 		return -EINVAL;
6571 	}
6572 
6573 	tmp &= bits->mask;
6574 
6575 	return (tmp == bits->val) ? 1 : 0;
6576 }
6577 
6578 #ifdef CONFIG_PM
6579 void ata_pci_device_do_suspend(struct pci_dev *pdev, pm_message_t mesg)
6580 {
6581 	pci_save_state(pdev);
6582 	pci_disable_device(pdev);
6583 
6584 	if (mesg.event & PM_EVENT_SLEEP)
6585 		pci_set_power_state(pdev, PCI_D3hot);
6586 }
6587 
6588 int ata_pci_device_do_resume(struct pci_dev *pdev)
6589 {
6590 	int rc;
6591 
6592 	pci_set_power_state(pdev, PCI_D0);
6593 	pci_restore_state(pdev);
6594 
6595 	rc = pcim_enable_device(pdev);
6596 	if (rc) {
6597 		dev_err(&pdev->dev,
6598 			"failed to enable device after resume (%d)\n", rc);
6599 		return rc;
6600 	}
6601 
6602 	pci_set_master(pdev);
6603 	return 0;
6604 }
6605 
6606 int ata_pci_device_suspend(struct pci_dev *pdev, pm_message_t mesg)
6607 {
6608 	struct ata_host *host = pci_get_drvdata(pdev);
6609 	int rc = 0;
6610 
6611 	rc = ata_host_suspend(host, mesg);
6612 	if (rc)
6613 		return rc;
6614 
6615 	ata_pci_device_do_suspend(pdev, mesg);
6616 
6617 	return 0;
6618 }
6619 
6620 int ata_pci_device_resume(struct pci_dev *pdev)
6621 {
6622 	struct ata_host *host = pci_get_drvdata(pdev);
6623 	int rc;
6624 
6625 	rc = ata_pci_device_do_resume(pdev);
6626 	if (rc == 0)
6627 		ata_host_resume(host);
6628 	return rc;
6629 }
6630 #endif /* CONFIG_PM */
6631 
6632 #endif /* CONFIG_PCI */
6633 
6634 /**
6635  *	ata_platform_remove_one - Platform layer callback for device removal
6636  *	@pdev: Platform device that was removed
6637  *
6638  *	Platform layer indicates to libata via this hook that hot-unplug or
6639  *	module unload event has occurred.  Detach all ports.  Resource
6640  *	release is handled via devres.
6641  *
6642  *	LOCKING:
6643  *	Inherited from platform layer (may sleep).
6644  */
6645 int ata_platform_remove_one(struct platform_device *pdev)
6646 {
6647 	struct ata_host *host = platform_get_drvdata(pdev);
6648 
6649 	ata_host_detach(host);
6650 
6651 	return 0;
6652 }
6653 
6654 static int __init ata_parse_force_one(char **cur,
6655 				      struct ata_force_ent *force_ent,
6656 				      const char **reason)
6657 {
6658 	static const struct ata_force_param force_tbl[] __initconst = {
6659 		{ "40c",	.cbl		= ATA_CBL_PATA40 },
6660 		{ "80c",	.cbl		= ATA_CBL_PATA80 },
6661 		{ "short40c",	.cbl		= ATA_CBL_PATA40_SHORT },
6662 		{ "unk",	.cbl		= ATA_CBL_PATA_UNK },
6663 		{ "ign",	.cbl		= ATA_CBL_PATA_IGN },
6664 		{ "sata",	.cbl		= ATA_CBL_SATA },
6665 		{ "1.5Gbps",	.spd_limit	= 1 },
6666 		{ "3.0Gbps",	.spd_limit	= 2 },
6667 		{ "noncq",	.horkage_on	= ATA_HORKAGE_NONCQ },
6668 		{ "ncq",	.horkage_off	= ATA_HORKAGE_NONCQ },
6669 		{ "noncqtrim",	.horkage_on	= ATA_HORKAGE_NO_NCQ_TRIM },
6670 		{ "ncqtrim",	.horkage_off	= ATA_HORKAGE_NO_NCQ_TRIM },
6671 		{ "dump_id",	.horkage_on	= ATA_HORKAGE_DUMP_ID },
6672 		{ "pio0",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 0) },
6673 		{ "pio1",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 1) },
6674 		{ "pio2",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 2) },
6675 		{ "pio3",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 3) },
6676 		{ "pio4",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 4) },
6677 		{ "pio5",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 5) },
6678 		{ "pio6",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 6) },
6679 		{ "mwdma0",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 0) },
6680 		{ "mwdma1",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 1) },
6681 		{ "mwdma2",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 2) },
6682 		{ "mwdma3",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 3) },
6683 		{ "mwdma4",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 4) },
6684 		{ "udma0",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 0) },
6685 		{ "udma16",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 0) },
6686 		{ "udma/16",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 0) },
6687 		{ "udma1",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 1) },
6688 		{ "udma25",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 1) },
6689 		{ "udma/25",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 1) },
6690 		{ "udma2",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 2) },
6691 		{ "udma33",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 2) },
6692 		{ "udma/33",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 2) },
6693 		{ "udma3",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 3) },
6694 		{ "udma44",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 3) },
6695 		{ "udma/44",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 3) },
6696 		{ "udma4",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 4) },
6697 		{ "udma66",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 4) },
6698 		{ "udma/66",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 4) },
6699 		{ "udma5",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 5) },
6700 		{ "udma100",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 5) },
6701 		{ "udma/100",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 5) },
6702 		{ "udma6",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 6) },
6703 		{ "udma133",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 6) },
6704 		{ "udma/133",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 6) },
6705 		{ "udma7",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 7) },
6706 		{ "nohrst",	.lflags		= ATA_LFLAG_NO_HRST },
6707 		{ "nosrst",	.lflags		= ATA_LFLAG_NO_SRST },
6708 		{ "norst",	.lflags		= ATA_LFLAG_NO_HRST | ATA_LFLAG_NO_SRST },
6709 		{ "rstonce",	.lflags		= ATA_LFLAG_RST_ONCE },
6710 		{ "atapi_dmadir", .horkage_on	= ATA_HORKAGE_ATAPI_DMADIR },
6711 		{ "disable",	.horkage_on	= ATA_HORKAGE_DISABLE },
6712 	};
6713 	char *start = *cur, *p = *cur;
6714 	char *id, *val, *endp;
6715 	const struct ata_force_param *match_fp = NULL;
6716 	int nr_matches = 0, i;
6717 
6718 	/* find where this param ends and update *cur */
6719 	while (*p != '\0' && *p != ',')
6720 		p++;
6721 
6722 	if (*p == '\0')
6723 		*cur = p;
6724 	else
6725 		*cur = p + 1;
6726 
6727 	*p = '\0';
6728 
6729 	/* parse */
6730 	p = strchr(start, ':');
6731 	if (!p) {
6732 		val = strstrip(start);
6733 		goto parse_val;
6734 	}
6735 	*p = '\0';
6736 
6737 	id = strstrip(start);
6738 	val = strstrip(p + 1);
6739 
6740 	/* parse id */
6741 	p = strchr(id, '.');
6742 	if (p) {
6743 		*p++ = '\0';
6744 		force_ent->device = simple_strtoul(p, &endp, 10);
6745 		if (p == endp || *endp != '\0') {
6746 			*reason = "invalid device";
6747 			return -EINVAL;
6748 		}
6749 	}
6750 
6751 	force_ent->port = simple_strtoul(id, &endp, 10);
6752 	if (p == endp || *endp != '\0') {
6753 		*reason = "invalid port/link";
6754 		return -EINVAL;
6755 	}
6756 
6757  parse_val:
6758 	/* parse val, allow shortcuts so that both 1.5 and 1.5Gbps work */
6759 	for (i = 0; i < ARRAY_SIZE(force_tbl); i++) {
6760 		const struct ata_force_param *fp = &force_tbl[i];
6761 
6762 		if (strncasecmp(val, fp->name, strlen(val)))
6763 			continue;
6764 
6765 		nr_matches++;
6766 		match_fp = fp;
6767 
6768 		if (strcasecmp(val, fp->name) == 0) {
6769 			nr_matches = 1;
6770 			break;
6771 		}
6772 	}
6773 
6774 	if (!nr_matches) {
6775 		*reason = "unknown value";
6776 		return -EINVAL;
6777 	}
6778 	if (nr_matches > 1) {
6779 		*reason = "ambigious value";
6780 		return -EINVAL;
6781 	}
6782 
6783 	force_ent->param = *match_fp;
6784 
6785 	return 0;
6786 }
6787 
6788 static void __init ata_parse_force_param(void)
6789 {
6790 	int idx = 0, size = 1;
6791 	int last_port = -1, last_device = -1;
6792 	char *p, *cur, *next;
6793 
6794 	/* calculate maximum number of params and allocate force_tbl */
6795 	for (p = ata_force_param_buf; *p; p++)
6796 		if (*p == ',')
6797 			size++;
6798 
6799 	ata_force_tbl = kzalloc(sizeof(ata_force_tbl[0]) * size, GFP_KERNEL);
6800 	if (!ata_force_tbl) {
6801 		printk(KERN_WARNING "ata: failed to extend force table, "
6802 		       "libata.force ignored\n");
6803 		return;
6804 	}
6805 
6806 	/* parse and populate the table */
6807 	for (cur = ata_force_param_buf; *cur != '\0'; cur = next) {
6808 		const char *reason = "";
6809 		struct ata_force_ent te = { .port = -1, .device = -1 };
6810 
6811 		next = cur;
6812 		if (ata_parse_force_one(&next, &te, &reason)) {
6813 			printk(KERN_WARNING "ata: failed to parse force "
6814 			       "parameter \"%s\" (%s)\n",
6815 			       cur, reason);
6816 			continue;
6817 		}
6818 
6819 		if (te.port == -1) {
6820 			te.port = last_port;
6821 			te.device = last_device;
6822 		}
6823 
6824 		ata_force_tbl[idx++] = te;
6825 
6826 		last_port = te.port;
6827 		last_device = te.device;
6828 	}
6829 
6830 	ata_force_tbl_size = idx;
6831 }
6832 
6833 static int __init ata_init(void)
6834 {
6835 	int rc;
6836 
6837 	ata_parse_force_param();
6838 
6839 	rc = ata_sff_init();
6840 	if (rc) {
6841 		kfree(ata_force_tbl);
6842 		return rc;
6843 	}
6844 
6845 	libata_transport_init();
6846 	ata_scsi_transport_template = ata_attach_transport();
6847 	if (!ata_scsi_transport_template) {
6848 		ata_sff_exit();
6849 		rc = -ENOMEM;
6850 		goto err_out;
6851 	}
6852 
6853 	printk(KERN_DEBUG "libata version " DRV_VERSION " loaded.\n");
6854 	return 0;
6855 
6856 err_out:
6857 	return rc;
6858 }
6859 
6860 static void __exit ata_exit(void)
6861 {
6862 	ata_release_transport(ata_scsi_transport_template);
6863 	libata_transport_exit();
6864 	ata_sff_exit();
6865 	kfree(ata_force_tbl);
6866 }
6867 
6868 subsys_initcall(ata_init);
6869 module_exit(ata_exit);
6870 
6871 static DEFINE_RATELIMIT_STATE(ratelimit, HZ / 5, 1);
6872 
6873 int ata_ratelimit(void)
6874 {
6875 	return __ratelimit(&ratelimit);
6876 }
6877 
6878 /**
6879  *	ata_msleep - ATA EH owner aware msleep
6880  *	@ap: ATA port to attribute the sleep to
6881  *	@msecs: duration to sleep in milliseconds
6882  *
6883  *	Sleeps @msecs.  If the current task is owner of @ap's EH, the
6884  *	ownership is released before going to sleep and reacquired
6885  *	after the sleep is complete.  IOW, other ports sharing the
6886  *	@ap->host will be allowed to own the EH while this task is
6887  *	sleeping.
6888  *
6889  *	LOCKING:
6890  *	Might sleep.
6891  */
6892 void ata_msleep(struct ata_port *ap, unsigned int msecs)
6893 {
6894 	bool owns_eh = ap && ap->host->eh_owner == current;
6895 
6896 	if (owns_eh)
6897 		ata_eh_release(ap);
6898 
6899 	if (msecs < 20) {
6900 		unsigned long usecs = msecs * USEC_PER_MSEC;
6901 		usleep_range(usecs, usecs + 50);
6902 	} else {
6903 		msleep(msecs);
6904 	}
6905 
6906 	if (owns_eh)
6907 		ata_eh_acquire(ap);
6908 }
6909 
6910 /**
6911  *	ata_wait_register - wait until register value changes
6912  *	@ap: ATA port to wait register for, can be NULL
6913  *	@reg: IO-mapped register
6914  *	@mask: Mask to apply to read register value
6915  *	@val: Wait condition
6916  *	@interval: polling interval in milliseconds
6917  *	@timeout: timeout in milliseconds
6918  *
6919  *	Waiting for some bits of register to change is a common
6920  *	operation for ATA controllers.  This function reads 32bit LE
6921  *	IO-mapped register @reg and tests for the following condition.
6922  *
6923  *	(*@reg & mask) != val
6924  *
6925  *	If the condition is met, it returns; otherwise, the process is
6926  *	repeated after @interval_msec until timeout.
6927  *
6928  *	LOCKING:
6929  *	Kernel thread context (may sleep)
6930  *
6931  *	RETURNS:
6932  *	The final register value.
6933  */
6934 u32 ata_wait_register(struct ata_port *ap, void __iomem *reg, u32 mask, u32 val,
6935 		      unsigned long interval, unsigned long timeout)
6936 {
6937 	unsigned long deadline;
6938 	u32 tmp;
6939 
6940 	tmp = ioread32(reg);
6941 
6942 	/* Calculate timeout _after_ the first read to make sure
6943 	 * preceding writes reach the controller before starting to
6944 	 * eat away the timeout.
6945 	 */
6946 	deadline = ata_deadline(jiffies, timeout);
6947 
6948 	while ((tmp & mask) == val && time_before(jiffies, deadline)) {
6949 		ata_msleep(ap, interval);
6950 		tmp = ioread32(reg);
6951 	}
6952 
6953 	return tmp;
6954 }
6955 
6956 /**
6957  *	sata_lpm_ignore_phy_events - test if PHY event should be ignored
6958  *	@link: Link receiving the event
6959  *
6960  *	Test whether the received PHY event has to be ignored or not.
6961  *
6962  *	LOCKING:
6963  *	None:
6964  *
6965  *	RETURNS:
6966  *	True if the event has to be ignored.
6967  */
6968 bool sata_lpm_ignore_phy_events(struct ata_link *link)
6969 {
6970 	unsigned long lpm_timeout = link->last_lpm_change +
6971 				    msecs_to_jiffies(ATA_TMOUT_SPURIOUS_PHY);
6972 
6973 	/* if LPM is enabled, PHYRDY doesn't mean anything */
6974 	if (link->lpm_policy > ATA_LPM_MAX_POWER)
6975 		return true;
6976 
6977 	/* ignore the first PHY event after the LPM policy changed
6978 	 * as it is might be spurious
6979 	 */
6980 	if ((link->flags & ATA_LFLAG_CHANGED) &&
6981 	    time_before(jiffies, lpm_timeout))
6982 		return true;
6983 
6984 	return false;
6985 }
6986 EXPORT_SYMBOL_GPL(sata_lpm_ignore_phy_events);
6987 
6988 /*
6989  * Dummy port_ops
6990  */
6991 static unsigned int ata_dummy_qc_issue(struct ata_queued_cmd *qc)
6992 {
6993 	return AC_ERR_SYSTEM;
6994 }
6995 
6996 static void ata_dummy_error_handler(struct ata_port *ap)
6997 {
6998 	/* truly dummy */
6999 }
7000 
7001 struct ata_port_operations ata_dummy_port_ops = {
7002 	.qc_prep		= ata_noop_qc_prep,
7003 	.qc_issue		= ata_dummy_qc_issue,
7004 	.error_handler		= ata_dummy_error_handler,
7005 	.sched_eh		= ata_std_sched_eh,
7006 	.end_eh			= ata_std_end_eh,
7007 };
7008 
7009 const struct ata_port_info ata_dummy_port_info = {
7010 	.port_ops		= &ata_dummy_port_ops,
7011 };
7012 
7013 /*
7014  * Utility print functions
7015  */
7016 void ata_port_printk(const struct ata_port *ap, const char *level,
7017 		     const char *fmt, ...)
7018 {
7019 	struct va_format vaf;
7020 	va_list args;
7021 
7022 	va_start(args, fmt);
7023 
7024 	vaf.fmt = fmt;
7025 	vaf.va = &args;
7026 
7027 	printk("%sata%u: %pV", level, ap->print_id, &vaf);
7028 
7029 	va_end(args);
7030 }
7031 EXPORT_SYMBOL(ata_port_printk);
7032 
7033 void ata_link_printk(const struct ata_link *link, const char *level,
7034 		     const char *fmt, ...)
7035 {
7036 	struct va_format vaf;
7037 	va_list args;
7038 
7039 	va_start(args, fmt);
7040 
7041 	vaf.fmt = fmt;
7042 	vaf.va = &args;
7043 
7044 	if (sata_pmp_attached(link->ap) || link->ap->slave_link)
7045 		printk("%sata%u.%02u: %pV",
7046 		       level, link->ap->print_id, link->pmp, &vaf);
7047 	else
7048 		printk("%sata%u: %pV",
7049 		       level, link->ap->print_id, &vaf);
7050 
7051 	va_end(args);
7052 }
7053 EXPORT_SYMBOL(ata_link_printk);
7054 
7055 void ata_dev_printk(const struct ata_device *dev, const char *level,
7056 		    const char *fmt, ...)
7057 {
7058 	struct va_format vaf;
7059 	va_list args;
7060 
7061 	va_start(args, fmt);
7062 
7063 	vaf.fmt = fmt;
7064 	vaf.va = &args;
7065 
7066 	printk("%sata%u.%02u: %pV",
7067 	       level, dev->link->ap->print_id, dev->link->pmp + dev->devno,
7068 	       &vaf);
7069 
7070 	va_end(args);
7071 }
7072 EXPORT_SYMBOL(ata_dev_printk);
7073 
7074 void ata_print_version(const struct device *dev, const char *version)
7075 {
7076 	dev_printk(KERN_DEBUG, dev, "version %s\n", version);
7077 }
7078 EXPORT_SYMBOL(ata_print_version);
7079 
7080 /*
7081  * libata is essentially a library of internal helper functions for
7082  * low-level ATA host controller drivers.  As such, the API/ABI is
7083  * likely to change as new drivers are added and updated.
7084  * Do not depend on ABI/API stability.
7085  */
7086 EXPORT_SYMBOL_GPL(sata_deb_timing_normal);
7087 EXPORT_SYMBOL_GPL(sata_deb_timing_hotplug);
7088 EXPORT_SYMBOL_GPL(sata_deb_timing_long);
7089 EXPORT_SYMBOL_GPL(ata_base_port_ops);
7090 EXPORT_SYMBOL_GPL(sata_port_ops);
7091 EXPORT_SYMBOL_GPL(ata_dummy_port_ops);
7092 EXPORT_SYMBOL_GPL(ata_dummy_port_info);
7093 EXPORT_SYMBOL_GPL(ata_link_next);
7094 EXPORT_SYMBOL_GPL(ata_dev_next);
7095 EXPORT_SYMBOL_GPL(ata_std_bios_param);
7096 EXPORT_SYMBOL_GPL(ata_scsi_unlock_native_capacity);
7097 EXPORT_SYMBOL_GPL(ata_host_init);
7098 EXPORT_SYMBOL_GPL(ata_host_alloc);
7099 EXPORT_SYMBOL_GPL(ata_host_alloc_pinfo);
7100 EXPORT_SYMBOL_GPL(ata_slave_link_init);
7101 EXPORT_SYMBOL_GPL(ata_host_start);
7102 EXPORT_SYMBOL_GPL(ata_host_register);
7103 EXPORT_SYMBOL_GPL(ata_host_activate);
7104 EXPORT_SYMBOL_GPL(ata_host_detach);
7105 EXPORT_SYMBOL_GPL(ata_sg_init);
7106 EXPORT_SYMBOL_GPL(ata_qc_complete);
7107 EXPORT_SYMBOL_GPL(ata_qc_complete_multiple);
7108 EXPORT_SYMBOL_GPL(atapi_cmd_type);
7109 EXPORT_SYMBOL_GPL(ata_tf_to_fis);
7110 EXPORT_SYMBOL_GPL(ata_tf_from_fis);
7111 EXPORT_SYMBOL_GPL(ata_pack_xfermask);
7112 EXPORT_SYMBOL_GPL(ata_unpack_xfermask);
7113 EXPORT_SYMBOL_GPL(ata_xfer_mask2mode);
7114 EXPORT_SYMBOL_GPL(ata_xfer_mode2mask);
7115 EXPORT_SYMBOL_GPL(ata_xfer_mode2shift);
7116 EXPORT_SYMBOL_GPL(ata_mode_string);
7117 EXPORT_SYMBOL_GPL(ata_id_xfermask);
7118 EXPORT_SYMBOL_GPL(ata_do_set_mode);
7119 EXPORT_SYMBOL_GPL(ata_std_qc_defer);
7120 EXPORT_SYMBOL_GPL(ata_noop_qc_prep);
7121 EXPORT_SYMBOL_GPL(ata_dev_disable);
7122 EXPORT_SYMBOL_GPL(sata_set_spd);
7123 EXPORT_SYMBOL_GPL(ata_wait_after_reset);
7124 EXPORT_SYMBOL_GPL(sata_link_debounce);
7125 EXPORT_SYMBOL_GPL(sata_link_resume);
7126 EXPORT_SYMBOL_GPL(sata_link_scr_lpm);
7127 EXPORT_SYMBOL_GPL(ata_std_prereset);
7128 EXPORT_SYMBOL_GPL(sata_link_hardreset);
7129 EXPORT_SYMBOL_GPL(sata_std_hardreset);
7130 EXPORT_SYMBOL_GPL(ata_std_postreset);
7131 EXPORT_SYMBOL_GPL(ata_dev_classify);
7132 EXPORT_SYMBOL_GPL(ata_dev_pair);
7133 EXPORT_SYMBOL_GPL(ata_ratelimit);
7134 EXPORT_SYMBOL_GPL(ata_msleep);
7135 EXPORT_SYMBOL_GPL(ata_wait_register);
7136 EXPORT_SYMBOL_GPL(ata_scsi_queuecmd);
7137 EXPORT_SYMBOL_GPL(ata_scsi_slave_config);
7138 EXPORT_SYMBOL_GPL(ata_scsi_slave_destroy);
7139 EXPORT_SYMBOL_GPL(ata_scsi_change_queue_depth);
7140 EXPORT_SYMBOL_GPL(__ata_change_queue_depth);
7141 EXPORT_SYMBOL_GPL(sata_scr_valid);
7142 EXPORT_SYMBOL_GPL(sata_scr_read);
7143 EXPORT_SYMBOL_GPL(sata_scr_write);
7144 EXPORT_SYMBOL_GPL(sata_scr_write_flush);
7145 EXPORT_SYMBOL_GPL(ata_link_online);
7146 EXPORT_SYMBOL_GPL(ata_link_offline);
7147 #ifdef CONFIG_PM
7148 EXPORT_SYMBOL_GPL(ata_host_suspend);
7149 EXPORT_SYMBOL_GPL(ata_host_resume);
7150 #endif /* CONFIG_PM */
7151 EXPORT_SYMBOL_GPL(ata_id_string);
7152 EXPORT_SYMBOL_GPL(ata_id_c_string);
7153 EXPORT_SYMBOL_GPL(ata_do_dev_read_id);
7154 EXPORT_SYMBOL_GPL(ata_scsi_simulate);
7155 
7156 EXPORT_SYMBOL_GPL(ata_pio_need_iordy);
7157 EXPORT_SYMBOL_GPL(ata_timing_find_mode);
7158 EXPORT_SYMBOL_GPL(ata_timing_compute);
7159 EXPORT_SYMBOL_GPL(ata_timing_merge);
7160 EXPORT_SYMBOL_GPL(ata_timing_cycle2mode);
7161 
7162 #ifdef CONFIG_PCI
7163 EXPORT_SYMBOL_GPL(pci_test_config_bits);
7164 EXPORT_SYMBOL_GPL(ata_pci_remove_one);
7165 #ifdef CONFIG_PM
7166 EXPORT_SYMBOL_GPL(ata_pci_device_do_suspend);
7167 EXPORT_SYMBOL_GPL(ata_pci_device_do_resume);
7168 EXPORT_SYMBOL_GPL(ata_pci_device_suspend);
7169 EXPORT_SYMBOL_GPL(ata_pci_device_resume);
7170 #endif /* CONFIG_PM */
7171 #endif /* CONFIG_PCI */
7172 
7173 EXPORT_SYMBOL_GPL(ata_platform_remove_one);
7174 
7175 EXPORT_SYMBOL_GPL(__ata_ehi_push_desc);
7176 EXPORT_SYMBOL_GPL(ata_ehi_push_desc);
7177 EXPORT_SYMBOL_GPL(ata_ehi_clear_desc);
7178 EXPORT_SYMBOL_GPL(ata_port_desc);
7179 #ifdef CONFIG_PCI
7180 EXPORT_SYMBOL_GPL(ata_port_pbar_desc);
7181 #endif /* CONFIG_PCI */
7182 EXPORT_SYMBOL_GPL(ata_port_schedule_eh);
7183 EXPORT_SYMBOL_GPL(ata_link_abort);
7184 EXPORT_SYMBOL_GPL(ata_port_abort);
7185 EXPORT_SYMBOL_GPL(ata_port_freeze);
7186 EXPORT_SYMBOL_GPL(sata_async_notification);
7187 EXPORT_SYMBOL_GPL(ata_eh_freeze_port);
7188 EXPORT_SYMBOL_GPL(ata_eh_thaw_port);
7189 EXPORT_SYMBOL_GPL(ata_eh_qc_complete);
7190 EXPORT_SYMBOL_GPL(ata_eh_qc_retry);
7191 EXPORT_SYMBOL_GPL(ata_eh_analyze_ncq_error);
7192 EXPORT_SYMBOL_GPL(ata_do_eh);
7193 EXPORT_SYMBOL_GPL(ata_std_error_handler);
7194 
7195 EXPORT_SYMBOL_GPL(ata_cable_40wire);
7196 EXPORT_SYMBOL_GPL(ata_cable_80wire);
7197 EXPORT_SYMBOL_GPL(ata_cable_unknown);
7198 EXPORT_SYMBOL_GPL(ata_cable_ignore);
7199 EXPORT_SYMBOL_GPL(ata_cable_sata);
7200