xref: /openbmc/linux/drivers/ata/libata-core.c (revision 8fa5723aa7e053d498336b48448b292fc2e0458b)
1 /*
2  *  libata-core.c - helper library for ATA
3  *
4  *  Maintained by:  Jeff Garzik <jgarzik@pobox.com>
5  *    		    Please ALWAYS copy linux-ide@vger.kernel.org
6  *		    on emails.
7  *
8  *  Copyright 2003-2004 Red Hat, Inc.  All rights reserved.
9  *  Copyright 2003-2004 Jeff Garzik
10  *
11  *
12  *  This program is free software; you can redistribute it and/or modify
13  *  it under the terms of the GNU General Public License as published by
14  *  the Free Software Foundation; either version 2, or (at your option)
15  *  any later version.
16  *
17  *  This program is distributed in the hope that it will be useful,
18  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
19  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  *  GNU General Public License for more details.
21  *
22  *  You should have received a copy of the GNU General Public License
23  *  along with this program; see the file COPYING.  If not, write to
24  *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
25  *
26  *
27  *  libata documentation is available via 'make {ps|pdf}docs',
28  *  as Documentation/DocBook/libata.*
29  *
30  *  Hardware documentation available from http://www.t13.org/ and
31  *  http://www.sata-io.org/
32  *
33  *  Standards documents from:
34  *	http://www.t13.org (ATA standards, PCI DMA IDE spec)
35  *	http://www.t10.org (SCSI MMC - for ATAPI MMC)
36  *	http://www.sata-io.org (SATA)
37  *	http://www.compactflash.org (CF)
38  *	http://www.qic.org (QIC157 - Tape and DSC)
39  *	http://www.ce-ata.org (CE-ATA: not supported)
40  *
41  */
42 
43 #include <linux/kernel.h>
44 #include <linux/module.h>
45 #include <linux/pci.h>
46 #include <linux/init.h>
47 #include <linux/list.h>
48 #include <linux/mm.h>
49 #include <linux/spinlock.h>
50 #include <linux/blkdev.h>
51 #include <linux/delay.h>
52 #include <linux/timer.h>
53 #include <linux/interrupt.h>
54 #include <linux/completion.h>
55 #include <linux/suspend.h>
56 #include <linux/workqueue.h>
57 #include <linux/scatterlist.h>
58 #include <linux/io.h>
59 #include <scsi/scsi.h>
60 #include <scsi/scsi_cmnd.h>
61 #include <scsi/scsi_host.h>
62 #include <linux/libata.h>
63 #include <asm/byteorder.h>
64 #include <linux/cdrom.h>
65 
66 #include "libata.h"
67 
68 
69 /* debounce timing parameters in msecs { interval, duration, timeout } */
70 const unsigned long sata_deb_timing_normal[]		= {   5,  100, 2000 };
71 const unsigned long sata_deb_timing_hotplug[]		= {  25,  500, 2000 };
72 const unsigned long sata_deb_timing_long[]		= { 100, 2000, 5000 };
73 
74 const struct ata_port_operations ata_base_port_ops = {
75 	.prereset		= ata_std_prereset,
76 	.postreset		= ata_std_postreset,
77 	.error_handler		= ata_std_error_handler,
78 };
79 
80 const struct ata_port_operations sata_port_ops = {
81 	.inherits		= &ata_base_port_ops,
82 
83 	.qc_defer		= ata_std_qc_defer,
84 	.hardreset		= sata_std_hardreset,
85 };
86 
87 static unsigned int ata_dev_init_params(struct ata_device *dev,
88 					u16 heads, u16 sectors);
89 static unsigned int ata_dev_set_xfermode(struct ata_device *dev);
90 static unsigned int ata_dev_set_feature(struct ata_device *dev,
91 					u8 enable, u8 feature);
92 static void ata_dev_xfermask(struct ata_device *dev);
93 static unsigned long ata_dev_blacklisted(const struct ata_device *dev);
94 
95 unsigned int ata_print_id = 1;
96 static struct workqueue_struct *ata_wq;
97 
98 struct workqueue_struct *ata_aux_wq;
99 
100 struct ata_force_param {
101 	const char	*name;
102 	unsigned int	cbl;
103 	int		spd_limit;
104 	unsigned long	xfer_mask;
105 	unsigned int	horkage_on;
106 	unsigned int	horkage_off;
107 	unsigned int	lflags;
108 };
109 
110 struct ata_force_ent {
111 	int			port;
112 	int			device;
113 	struct ata_force_param	param;
114 };
115 
116 static struct ata_force_ent *ata_force_tbl;
117 static int ata_force_tbl_size;
118 
119 static char ata_force_param_buf[PAGE_SIZE] __initdata;
120 /* param_buf is thrown away after initialization, disallow read */
121 module_param_string(force, ata_force_param_buf, sizeof(ata_force_param_buf), 0);
122 MODULE_PARM_DESC(force, "Force ATA configurations including cable type, link speed and transfer mode (see Documentation/kernel-parameters.txt for details)");
123 
124 static int atapi_enabled = 1;
125 module_param(atapi_enabled, int, 0444);
126 MODULE_PARM_DESC(atapi_enabled, "Enable discovery of ATAPI devices (0=off, 1=on)");
127 
128 static int atapi_dmadir = 0;
129 module_param(atapi_dmadir, int, 0444);
130 MODULE_PARM_DESC(atapi_dmadir, "Enable ATAPI DMADIR bridge support (0=off, 1=on)");
131 
132 int atapi_passthru16 = 1;
133 module_param(atapi_passthru16, int, 0444);
134 MODULE_PARM_DESC(atapi_passthru16, "Enable ATA_16 passthru for ATAPI devices; on by default (0=off, 1=on)");
135 
136 int libata_fua = 0;
137 module_param_named(fua, libata_fua, int, 0444);
138 MODULE_PARM_DESC(fua, "FUA support (0=off, 1=on)");
139 
140 static int ata_ignore_hpa;
141 module_param_named(ignore_hpa, ata_ignore_hpa, int, 0644);
142 MODULE_PARM_DESC(ignore_hpa, "Ignore HPA limit (0=keep BIOS limits, 1=ignore limits, using full disk)");
143 
144 static int libata_dma_mask = ATA_DMA_MASK_ATA|ATA_DMA_MASK_ATAPI|ATA_DMA_MASK_CFA;
145 module_param_named(dma, libata_dma_mask, int, 0444);
146 MODULE_PARM_DESC(dma, "DMA enable/disable (0x1==ATA, 0x2==ATAPI, 0x4==CF)");
147 
148 static int ata_probe_timeout;
149 module_param(ata_probe_timeout, int, 0444);
150 MODULE_PARM_DESC(ata_probe_timeout, "Set ATA probing timeout (seconds)");
151 
152 int libata_noacpi = 0;
153 module_param_named(noacpi, libata_noacpi, int, 0444);
154 MODULE_PARM_DESC(noacpi, "Disables the use of ACPI in probe/suspend/resume when set");
155 
156 int libata_allow_tpm = 0;
157 module_param_named(allow_tpm, libata_allow_tpm, int, 0444);
158 MODULE_PARM_DESC(allow_tpm, "Permit the use of TPM commands");
159 
160 MODULE_AUTHOR("Jeff Garzik");
161 MODULE_DESCRIPTION("Library module for ATA devices");
162 MODULE_LICENSE("GPL");
163 MODULE_VERSION(DRV_VERSION);
164 
165 
166 /*
167  * Iterator helpers.  Don't use directly.
168  *
169  * LOCKING:
170  * Host lock or EH context.
171  */
172 struct ata_link *__ata_port_next_link(struct ata_port *ap,
173 				      struct ata_link *link, bool dev_only)
174 {
175 	/* NULL link indicates start of iteration */
176 	if (!link) {
177 		if (dev_only && sata_pmp_attached(ap))
178 			return ap->pmp_link;
179 		return &ap->link;
180 	}
181 
182 	/* we just iterated over the host master link, what's next? */
183 	if (link == &ap->link) {
184 		if (!sata_pmp_attached(ap)) {
185 			if (unlikely(ap->slave_link) && !dev_only)
186 				return ap->slave_link;
187 			return NULL;
188 		}
189 		return ap->pmp_link;
190 	}
191 
192 	/* slave_link excludes PMP */
193 	if (unlikely(link == ap->slave_link))
194 		return NULL;
195 
196 	/* iterate to the next PMP link */
197 	if (++link < ap->pmp_link + ap->nr_pmp_links)
198 		return link;
199 	return NULL;
200 }
201 
202 /**
203  *	ata_dev_phys_link - find physical link for a device
204  *	@dev: ATA device to look up physical link for
205  *
206  *	Look up physical link which @dev is attached to.  Note that
207  *	this is different from @dev->link only when @dev is on slave
208  *	link.  For all other cases, it's the same as @dev->link.
209  *
210  *	LOCKING:
211  *	Don't care.
212  *
213  *	RETURNS:
214  *	Pointer to the found physical link.
215  */
216 struct ata_link *ata_dev_phys_link(struct ata_device *dev)
217 {
218 	struct ata_port *ap = dev->link->ap;
219 
220 	if (!ap->slave_link)
221 		return dev->link;
222 	if (!dev->devno)
223 		return &ap->link;
224 	return ap->slave_link;
225 }
226 
227 /**
228  *	ata_force_cbl - force cable type according to libata.force
229  *	@ap: ATA port of interest
230  *
231  *	Force cable type according to libata.force and whine about it.
232  *	The last entry which has matching port number is used, so it
233  *	can be specified as part of device force parameters.  For
234  *	example, both "a:40c,1.00:udma4" and "1.00:40c,udma4" have the
235  *	same effect.
236  *
237  *	LOCKING:
238  *	EH context.
239  */
240 void ata_force_cbl(struct ata_port *ap)
241 {
242 	int i;
243 
244 	for (i = ata_force_tbl_size - 1; i >= 0; i--) {
245 		const struct ata_force_ent *fe = &ata_force_tbl[i];
246 
247 		if (fe->port != -1 && fe->port != ap->print_id)
248 			continue;
249 
250 		if (fe->param.cbl == ATA_CBL_NONE)
251 			continue;
252 
253 		ap->cbl = fe->param.cbl;
254 		ata_port_printk(ap, KERN_NOTICE,
255 				"FORCE: cable set to %s\n", fe->param.name);
256 		return;
257 	}
258 }
259 
260 /**
261  *	ata_force_link_limits - force link limits according to libata.force
262  *	@link: ATA link of interest
263  *
264  *	Force link flags and SATA spd limit according to libata.force
265  *	and whine about it.  When only the port part is specified
266  *	(e.g. 1:), the limit applies to all links connected to both
267  *	the host link and all fan-out ports connected via PMP.  If the
268  *	device part is specified as 0 (e.g. 1.00:), it specifies the
269  *	first fan-out link not the host link.  Device number 15 always
270  *	points to the host link whether PMP is attached or not.  If the
271  *	controller has slave link, device number 16 points to it.
272  *
273  *	LOCKING:
274  *	EH context.
275  */
276 static void ata_force_link_limits(struct ata_link *link)
277 {
278 	bool did_spd = false;
279 	int linkno = link->pmp;
280 	int i;
281 
282 	if (ata_is_host_link(link))
283 		linkno += 15;
284 
285 	for (i = ata_force_tbl_size - 1; i >= 0; i--) {
286 		const struct ata_force_ent *fe = &ata_force_tbl[i];
287 
288 		if (fe->port != -1 && fe->port != link->ap->print_id)
289 			continue;
290 
291 		if (fe->device != -1 && fe->device != linkno)
292 			continue;
293 
294 		/* only honor the first spd limit */
295 		if (!did_spd && fe->param.spd_limit) {
296 			link->hw_sata_spd_limit = (1 << fe->param.spd_limit) - 1;
297 			ata_link_printk(link, KERN_NOTICE,
298 					"FORCE: PHY spd limit set to %s\n",
299 					fe->param.name);
300 			did_spd = true;
301 		}
302 
303 		/* let lflags stack */
304 		if (fe->param.lflags) {
305 			link->flags |= fe->param.lflags;
306 			ata_link_printk(link, KERN_NOTICE,
307 					"FORCE: link flag 0x%x forced -> 0x%x\n",
308 					fe->param.lflags, link->flags);
309 		}
310 	}
311 }
312 
313 /**
314  *	ata_force_xfermask - force xfermask according to libata.force
315  *	@dev: ATA device of interest
316  *
317  *	Force xfer_mask according to libata.force and whine about it.
318  *	For consistency with link selection, device number 15 selects
319  *	the first device connected to the host link.
320  *
321  *	LOCKING:
322  *	EH context.
323  */
324 static void ata_force_xfermask(struct ata_device *dev)
325 {
326 	int devno = dev->link->pmp + dev->devno;
327 	int alt_devno = devno;
328 	int i;
329 
330 	/* allow n.15/16 for devices attached to host port */
331 	if (ata_is_host_link(dev->link))
332 		alt_devno += 15;
333 
334 	for (i = ata_force_tbl_size - 1; i >= 0; i--) {
335 		const struct ata_force_ent *fe = &ata_force_tbl[i];
336 		unsigned long pio_mask, mwdma_mask, udma_mask;
337 
338 		if (fe->port != -1 && fe->port != dev->link->ap->print_id)
339 			continue;
340 
341 		if (fe->device != -1 && fe->device != devno &&
342 		    fe->device != alt_devno)
343 			continue;
344 
345 		if (!fe->param.xfer_mask)
346 			continue;
347 
348 		ata_unpack_xfermask(fe->param.xfer_mask,
349 				    &pio_mask, &mwdma_mask, &udma_mask);
350 		if (udma_mask)
351 			dev->udma_mask = udma_mask;
352 		else if (mwdma_mask) {
353 			dev->udma_mask = 0;
354 			dev->mwdma_mask = mwdma_mask;
355 		} else {
356 			dev->udma_mask = 0;
357 			dev->mwdma_mask = 0;
358 			dev->pio_mask = pio_mask;
359 		}
360 
361 		ata_dev_printk(dev, KERN_NOTICE,
362 			"FORCE: xfer_mask set to %s\n", fe->param.name);
363 		return;
364 	}
365 }
366 
367 /**
368  *	ata_force_horkage - force horkage according to libata.force
369  *	@dev: ATA device of interest
370  *
371  *	Force horkage according to libata.force and whine about it.
372  *	For consistency with link selection, device number 15 selects
373  *	the first device connected to the host link.
374  *
375  *	LOCKING:
376  *	EH context.
377  */
378 static void ata_force_horkage(struct ata_device *dev)
379 {
380 	int devno = dev->link->pmp + dev->devno;
381 	int alt_devno = devno;
382 	int i;
383 
384 	/* allow n.15/16 for devices attached to host port */
385 	if (ata_is_host_link(dev->link))
386 		alt_devno += 15;
387 
388 	for (i = 0; i < ata_force_tbl_size; i++) {
389 		const struct ata_force_ent *fe = &ata_force_tbl[i];
390 
391 		if (fe->port != -1 && fe->port != dev->link->ap->print_id)
392 			continue;
393 
394 		if (fe->device != -1 && fe->device != devno &&
395 		    fe->device != alt_devno)
396 			continue;
397 
398 		if (!(~dev->horkage & fe->param.horkage_on) &&
399 		    !(dev->horkage & fe->param.horkage_off))
400 			continue;
401 
402 		dev->horkage |= fe->param.horkage_on;
403 		dev->horkage &= ~fe->param.horkage_off;
404 
405 		ata_dev_printk(dev, KERN_NOTICE,
406 			"FORCE: horkage modified (%s)\n", fe->param.name);
407 	}
408 }
409 
410 /**
411  *	atapi_cmd_type - Determine ATAPI command type from SCSI opcode
412  *	@opcode: SCSI opcode
413  *
414  *	Determine ATAPI command type from @opcode.
415  *
416  *	LOCKING:
417  *	None.
418  *
419  *	RETURNS:
420  *	ATAPI_{READ|WRITE|READ_CD|PASS_THRU|MISC}
421  */
422 int atapi_cmd_type(u8 opcode)
423 {
424 	switch (opcode) {
425 	case GPCMD_READ_10:
426 	case GPCMD_READ_12:
427 		return ATAPI_READ;
428 
429 	case GPCMD_WRITE_10:
430 	case GPCMD_WRITE_12:
431 	case GPCMD_WRITE_AND_VERIFY_10:
432 		return ATAPI_WRITE;
433 
434 	case GPCMD_READ_CD:
435 	case GPCMD_READ_CD_MSF:
436 		return ATAPI_READ_CD;
437 
438 	case ATA_16:
439 	case ATA_12:
440 		if (atapi_passthru16)
441 			return ATAPI_PASS_THRU;
442 		/* fall thru */
443 	default:
444 		return ATAPI_MISC;
445 	}
446 }
447 
448 /**
449  *	ata_tf_to_fis - Convert ATA taskfile to SATA FIS structure
450  *	@tf: Taskfile to convert
451  *	@pmp: Port multiplier port
452  *	@is_cmd: This FIS is for command
453  *	@fis: Buffer into which data will output
454  *
455  *	Converts a standard ATA taskfile to a Serial ATA
456  *	FIS structure (Register - Host to Device).
457  *
458  *	LOCKING:
459  *	Inherited from caller.
460  */
461 void ata_tf_to_fis(const struct ata_taskfile *tf, u8 pmp, int is_cmd, u8 *fis)
462 {
463 	fis[0] = 0x27;			/* Register - Host to Device FIS */
464 	fis[1] = pmp & 0xf;		/* Port multiplier number*/
465 	if (is_cmd)
466 		fis[1] |= (1 << 7);	/* bit 7 indicates Command FIS */
467 
468 	fis[2] = tf->command;
469 	fis[3] = tf->feature;
470 
471 	fis[4] = tf->lbal;
472 	fis[5] = tf->lbam;
473 	fis[6] = tf->lbah;
474 	fis[7] = tf->device;
475 
476 	fis[8] = tf->hob_lbal;
477 	fis[9] = tf->hob_lbam;
478 	fis[10] = tf->hob_lbah;
479 	fis[11] = tf->hob_feature;
480 
481 	fis[12] = tf->nsect;
482 	fis[13] = tf->hob_nsect;
483 	fis[14] = 0;
484 	fis[15] = tf->ctl;
485 
486 	fis[16] = 0;
487 	fis[17] = 0;
488 	fis[18] = 0;
489 	fis[19] = 0;
490 }
491 
492 /**
493  *	ata_tf_from_fis - Convert SATA FIS to ATA taskfile
494  *	@fis: Buffer from which data will be input
495  *	@tf: Taskfile to output
496  *
497  *	Converts a serial ATA FIS structure to a standard ATA taskfile.
498  *
499  *	LOCKING:
500  *	Inherited from caller.
501  */
502 
503 void ata_tf_from_fis(const u8 *fis, struct ata_taskfile *tf)
504 {
505 	tf->command	= fis[2];	/* status */
506 	tf->feature	= fis[3];	/* error */
507 
508 	tf->lbal	= fis[4];
509 	tf->lbam	= fis[5];
510 	tf->lbah	= fis[6];
511 	tf->device	= fis[7];
512 
513 	tf->hob_lbal	= fis[8];
514 	tf->hob_lbam	= fis[9];
515 	tf->hob_lbah	= fis[10];
516 
517 	tf->nsect	= fis[12];
518 	tf->hob_nsect	= fis[13];
519 }
520 
521 static const u8 ata_rw_cmds[] = {
522 	/* pio multi */
523 	ATA_CMD_READ_MULTI,
524 	ATA_CMD_WRITE_MULTI,
525 	ATA_CMD_READ_MULTI_EXT,
526 	ATA_CMD_WRITE_MULTI_EXT,
527 	0,
528 	0,
529 	0,
530 	ATA_CMD_WRITE_MULTI_FUA_EXT,
531 	/* pio */
532 	ATA_CMD_PIO_READ,
533 	ATA_CMD_PIO_WRITE,
534 	ATA_CMD_PIO_READ_EXT,
535 	ATA_CMD_PIO_WRITE_EXT,
536 	0,
537 	0,
538 	0,
539 	0,
540 	/* dma */
541 	ATA_CMD_READ,
542 	ATA_CMD_WRITE,
543 	ATA_CMD_READ_EXT,
544 	ATA_CMD_WRITE_EXT,
545 	0,
546 	0,
547 	0,
548 	ATA_CMD_WRITE_FUA_EXT
549 };
550 
551 /**
552  *	ata_rwcmd_protocol - set taskfile r/w commands and protocol
553  *	@tf: command to examine and configure
554  *	@dev: device tf belongs to
555  *
556  *	Examine the device configuration and tf->flags to calculate
557  *	the proper read/write commands and protocol to use.
558  *
559  *	LOCKING:
560  *	caller.
561  */
562 static int ata_rwcmd_protocol(struct ata_taskfile *tf, struct ata_device *dev)
563 {
564 	u8 cmd;
565 
566 	int index, fua, lba48, write;
567 
568 	fua = (tf->flags & ATA_TFLAG_FUA) ? 4 : 0;
569 	lba48 = (tf->flags & ATA_TFLAG_LBA48) ? 2 : 0;
570 	write = (tf->flags & ATA_TFLAG_WRITE) ? 1 : 0;
571 
572 	if (dev->flags & ATA_DFLAG_PIO) {
573 		tf->protocol = ATA_PROT_PIO;
574 		index = dev->multi_count ? 0 : 8;
575 	} else if (lba48 && (dev->link->ap->flags & ATA_FLAG_PIO_LBA48)) {
576 		/* Unable to use DMA due to host limitation */
577 		tf->protocol = ATA_PROT_PIO;
578 		index = dev->multi_count ? 0 : 8;
579 	} else {
580 		tf->protocol = ATA_PROT_DMA;
581 		index = 16;
582 	}
583 
584 	cmd = ata_rw_cmds[index + fua + lba48 + write];
585 	if (cmd) {
586 		tf->command = cmd;
587 		return 0;
588 	}
589 	return -1;
590 }
591 
592 /**
593  *	ata_tf_read_block - Read block address from ATA taskfile
594  *	@tf: ATA taskfile of interest
595  *	@dev: ATA device @tf belongs to
596  *
597  *	LOCKING:
598  *	None.
599  *
600  *	Read block address from @tf.  This function can handle all
601  *	three address formats - LBA, LBA48 and CHS.  tf->protocol and
602  *	flags select the address format to use.
603  *
604  *	RETURNS:
605  *	Block address read from @tf.
606  */
607 u64 ata_tf_read_block(struct ata_taskfile *tf, struct ata_device *dev)
608 {
609 	u64 block = 0;
610 
611 	if (tf->flags & ATA_TFLAG_LBA) {
612 		if (tf->flags & ATA_TFLAG_LBA48) {
613 			block |= (u64)tf->hob_lbah << 40;
614 			block |= (u64)tf->hob_lbam << 32;
615 			block |= tf->hob_lbal << 24;
616 		} else
617 			block |= (tf->device & 0xf) << 24;
618 
619 		block |= tf->lbah << 16;
620 		block |= tf->lbam << 8;
621 		block |= tf->lbal;
622 	} else {
623 		u32 cyl, head, sect;
624 
625 		cyl = tf->lbam | (tf->lbah << 8);
626 		head = tf->device & 0xf;
627 		sect = tf->lbal;
628 
629 		block = (cyl * dev->heads + head) * dev->sectors + sect;
630 	}
631 
632 	return block;
633 }
634 
635 /**
636  *	ata_build_rw_tf - Build ATA taskfile for given read/write request
637  *	@tf: Target ATA taskfile
638  *	@dev: ATA device @tf belongs to
639  *	@block: Block address
640  *	@n_block: Number of blocks
641  *	@tf_flags: RW/FUA etc...
642  *	@tag: tag
643  *
644  *	LOCKING:
645  *	None.
646  *
647  *	Build ATA taskfile @tf for read/write request described by
648  *	@block, @n_block, @tf_flags and @tag on @dev.
649  *
650  *	RETURNS:
651  *
652  *	0 on success, -ERANGE if the request is too large for @dev,
653  *	-EINVAL if the request is invalid.
654  */
655 int ata_build_rw_tf(struct ata_taskfile *tf, struct ata_device *dev,
656 		    u64 block, u32 n_block, unsigned int tf_flags,
657 		    unsigned int tag)
658 {
659 	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
660 	tf->flags |= tf_flags;
661 
662 	if (ata_ncq_enabled(dev) && likely(tag != ATA_TAG_INTERNAL)) {
663 		/* yay, NCQ */
664 		if (!lba_48_ok(block, n_block))
665 			return -ERANGE;
666 
667 		tf->protocol = ATA_PROT_NCQ;
668 		tf->flags |= ATA_TFLAG_LBA | ATA_TFLAG_LBA48;
669 
670 		if (tf->flags & ATA_TFLAG_WRITE)
671 			tf->command = ATA_CMD_FPDMA_WRITE;
672 		else
673 			tf->command = ATA_CMD_FPDMA_READ;
674 
675 		tf->nsect = tag << 3;
676 		tf->hob_feature = (n_block >> 8) & 0xff;
677 		tf->feature = n_block & 0xff;
678 
679 		tf->hob_lbah = (block >> 40) & 0xff;
680 		tf->hob_lbam = (block >> 32) & 0xff;
681 		tf->hob_lbal = (block >> 24) & 0xff;
682 		tf->lbah = (block >> 16) & 0xff;
683 		tf->lbam = (block >> 8) & 0xff;
684 		tf->lbal = block & 0xff;
685 
686 		tf->device = 1 << 6;
687 		if (tf->flags & ATA_TFLAG_FUA)
688 			tf->device |= 1 << 7;
689 	} else if (dev->flags & ATA_DFLAG_LBA) {
690 		tf->flags |= ATA_TFLAG_LBA;
691 
692 		if (lba_28_ok(block, n_block)) {
693 			/* use LBA28 */
694 			tf->device |= (block >> 24) & 0xf;
695 		} else if (lba_48_ok(block, n_block)) {
696 			if (!(dev->flags & ATA_DFLAG_LBA48))
697 				return -ERANGE;
698 
699 			/* use LBA48 */
700 			tf->flags |= ATA_TFLAG_LBA48;
701 
702 			tf->hob_nsect = (n_block >> 8) & 0xff;
703 
704 			tf->hob_lbah = (block >> 40) & 0xff;
705 			tf->hob_lbam = (block >> 32) & 0xff;
706 			tf->hob_lbal = (block >> 24) & 0xff;
707 		} else
708 			/* request too large even for LBA48 */
709 			return -ERANGE;
710 
711 		if (unlikely(ata_rwcmd_protocol(tf, dev) < 0))
712 			return -EINVAL;
713 
714 		tf->nsect = n_block & 0xff;
715 
716 		tf->lbah = (block >> 16) & 0xff;
717 		tf->lbam = (block >> 8) & 0xff;
718 		tf->lbal = block & 0xff;
719 
720 		tf->device |= ATA_LBA;
721 	} else {
722 		/* CHS */
723 		u32 sect, head, cyl, track;
724 
725 		/* The request -may- be too large for CHS addressing. */
726 		if (!lba_28_ok(block, n_block))
727 			return -ERANGE;
728 
729 		if (unlikely(ata_rwcmd_protocol(tf, dev) < 0))
730 			return -EINVAL;
731 
732 		/* Convert LBA to CHS */
733 		track = (u32)block / dev->sectors;
734 		cyl   = track / dev->heads;
735 		head  = track % dev->heads;
736 		sect  = (u32)block % dev->sectors + 1;
737 
738 		DPRINTK("block %u track %u cyl %u head %u sect %u\n",
739 			(u32)block, track, cyl, head, sect);
740 
741 		/* Check whether the converted CHS can fit.
742 		   Cylinder: 0-65535
743 		   Head: 0-15
744 		   Sector: 1-255*/
745 		if ((cyl >> 16) || (head >> 4) || (sect >> 8) || (!sect))
746 			return -ERANGE;
747 
748 		tf->nsect = n_block & 0xff; /* Sector count 0 means 256 sectors */
749 		tf->lbal = sect;
750 		tf->lbam = cyl;
751 		tf->lbah = cyl >> 8;
752 		tf->device |= head;
753 	}
754 
755 	return 0;
756 }
757 
758 /**
759  *	ata_pack_xfermask - Pack pio, mwdma and udma masks into xfer_mask
760  *	@pio_mask: pio_mask
761  *	@mwdma_mask: mwdma_mask
762  *	@udma_mask: udma_mask
763  *
764  *	Pack @pio_mask, @mwdma_mask and @udma_mask into a single
765  *	unsigned int xfer_mask.
766  *
767  *	LOCKING:
768  *	None.
769  *
770  *	RETURNS:
771  *	Packed xfer_mask.
772  */
773 unsigned long ata_pack_xfermask(unsigned long pio_mask,
774 				unsigned long mwdma_mask,
775 				unsigned long udma_mask)
776 {
777 	return ((pio_mask << ATA_SHIFT_PIO) & ATA_MASK_PIO) |
778 		((mwdma_mask << ATA_SHIFT_MWDMA) & ATA_MASK_MWDMA) |
779 		((udma_mask << ATA_SHIFT_UDMA) & ATA_MASK_UDMA);
780 }
781 
782 /**
783  *	ata_unpack_xfermask - Unpack xfer_mask into pio, mwdma and udma masks
784  *	@xfer_mask: xfer_mask to unpack
785  *	@pio_mask: resulting pio_mask
786  *	@mwdma_mask: resulting mwdma_mask
787  *	@udma_mask: resulting udma_mask
788  *
789  *	Unpack @xfer_mask into @pio_mask, @mwdma_mask and @udma_mask.
790  *	Any NULL distination masks will be ignored.
791  */
792 void ata_unpack_xfermask(unsigned long xfer_mask, unsigned long *pio_mask,
793 			 unsigned long *mwdma_mask, unsigned long *udma_mask)
794 {
795 	if (pio_mask)
796 		*pio_mask = (xfer_mask & ATA_MASK_PIO) >> ATA_SHIFT_PIO;
797 	if (mwdma_mask)
798 		*mwdma_mask = (xfer_mask & ATA_MASK_MWDMA) >> ATA_SHIFT_MWDMA;
799 	if (udma_mask)
800 		*udma_mask = (xfer_mask & ATA_MASK_UDMA) >> ATA_SHIFT_UDMA;
801 }
802 
803 static const struct ata_xfer_ent {
804 	int shift, bits;
805 	u8 base;
806 } ata_xfer_tbl[] = {
807 	{ ATA_SHIFT_PIO, ATA_NR_PIO_MODES, XFER_PIO_0 },
808 	{ ATA_SHIFT_MWDMA, ATA_NR_MWDMA_MODES, XFER_MW_DMA_0 },
809 	{ ATA_SHIFT_UDMA, ATA_NR_UDMA_MODES, XFER_UDMA_0 },
810 	{ -1, },
811 };
812 
813 /**
814  *	ata_xfer_mask2mode - Find matching XFER_* for the given xfer_mask
815  *	@xfer_mask: xfer_mask of interest
816  *
817  *	Return matching XFER_* value for @xfer_mask.  Only the highest
818  *	bit of @xfer_mask is considered.
819  *
820  *	LOCKING:
821  *	None.
822  *
823  *	RETURNS:
824  *	Matching XFER_* value, 0xff if no match found.
825  */
826 u8 ata_xfer_mask2mode(unsigned long xfer_mask)
827 {
828 	int highbit = fls(xfer_mask) - 1;
829 	const struct ata_xfer_ent *ent;
830 
831 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
832 		if (highbit >= ent->shift && highbit < ent->shift + ent->bits)
833 			return ent->base + highbit - ent->shift;
834 	return 0xff;
835 }
836 
837 /**
838  *	ata_xfer_mode2mask - Find matching xfer_mask for XFER_*
839  *	@xfer_mode: XFER_* of interest
840  *
841  *	Return matching xfer_mask for @xfer_mode.
842  *
843  *	LOCKING:
844  *	None.
845  *
846  *	RETURNS:
847  *	Matching xfer_mask, 0 if no match found.
848  */
849 unsigned long ata_xfer_mode2mask(u8 xfer_mode)
850 {
851 	const struct ata_xfer_ent *ent;
852 
853 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
854 		if (xfer_mode >= ent->base && xfer_mode < ent->base + ent->bits)
855 			return ((2 << (ent->shift + xfer_mode - ent->base)) - 1)
856 				& ~((1 << ent->shift) - 1);
857 	return 0;
858 }
859 
860 /**
861  *	ata_xfer_mode2shift - Find matching xfer_shift for XFER_*
862  *	@xfer_mode: XFER_* of interest
863  *
864  *	Return matching xfer_shift for @xfer_mode.
865  *
866  *	LOCKING:
867  *	None.
868  *
869  *	RETURNS:
870  *	Matching xfer_shift, -1 if no match found.
871  */
872 int ata_xfer_mode2shift(unsigned long xfer_mode)
873 {
874 	const struct ata_xfer_ent *ent;
875 
876 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
877 		if (xfer_mode >= ent->base && xfer_mode < ent->base + ent->bits)
878 			return ent->shift;
879 	return -1;
880 }
881 
882 /**
883  *	ata_mode_string - convert xfer_mask to string
884  *	@xfer_mask: mask of bits supported; only highest bit counts.
885  *
886  *	Determine string which represents the highest speed
887  *	(highest bit in @modemask).
888  *
889  *	LOCKING:
890  *	None.
891  *
892  *	RETURNS:
893  *	Constant C string representing highest speed listed in
894  *	@mode_mask, or the constant C string "<n/a>".
895  */
896 const char *ata_mode_string(unsigned long xfer_mask)
897 {
898 	static const char * const xfer_mode_str[] = {
899 		"PIO0",
900 		"PIO1",
901 		"PIO2",
902 		"PIO3",
903 		"PIO4",
904 		"PIO5",
905 		"PIO6",
906 		"MWDMA0",
907 		"MWDMA1",
908 		"MWDMA2",
909 		"MWDMA3",
910 		"MWDMA4",
911 		"UDMA/16",
912 		"UDMA/25",
913 		"UDMA/33",
914 		"UDMA/44",
915 		"UDMA/66",
916 		"UDMA/100",
917 		"UDMA/133",
918 		"UDMA7",
919 	};
920 	int highbit;
921 
922 	highbit = fls(xfer_mask) - 1;
923 	if (highbit >= 0 && highbit < ARRAY_SIZE(xfer_mode_str))
924 		return xfer_mode_str[highbit];
925 	return "<n/a>";
926 }
927 
928 static const char *sata_spd_string(unsigned int spd)
929 {
930 	static const char * const spd_str[] = {
931 		"1.5 Gbps",
932 		"3.0 Gbps",
933 	};
934 
935 	if (spd == 0 || (spd - 1) >= ARRAY_SIZE(spd_str))
936 		return "<unknown>";
937 	return spd_str[spd - 1];
938 }
939 
940 void ata_dev_disable(struct ata_device *dev)
941 {
942 	if (ata_dev_enabled(dev)) {
943 		if (ata_msg_drv(dev->link->ap))
944 			ata_dev_printk(dev, KERN_WARNING, "disabled\n");
945 		ata_acpi_on_disable(dev);
946 		ata_down_xfermask_limit(dev, ATA_DNXFER_FORCE_PIO0 |
947 					     ATA_DNXFER_QUIET);
948 		dev->class++;
949 	}
950 }
951 
952 static int ata_dev_set_dipm(struct ata_device *dev, enum link_pm policy)
953 {
954 	struct ata_link *link = dev->link;
955 	struct ata_port *ap = link->ap;
956 	u32 scontrol;
957 	unsigned int err_mask;
958 	int rc;
959 
960 	/*
961 	 * disallow DIPM for drivers which haven't set
962 	 * ATA_FLAG_IPM.  This is because when DIPM is enabled,
963 	 * phy ready will be set in the interrupt status on
964 	 * state changes, which will cause some drivers to
965 	 * think there are errors - additionally drivers will
966 	 * need to disable hot plug.
967 	 */
968 	if (!(ap->flags & ATA_FLAG_IPM) || !ata_dev_enabled(dev)) {
969 		ap->pm_policy = NOT_AVAILABLE;
970 		return -EINVAL;
971 	}
972 
973 	/*
974 	 * For DIPM, we will only enable it for the
975 	 * min_power setting.
976 	 *
977 	 * Why?  Because Disks are too stupid to know that
978 	 * If the host rejects a request to go to SLUMBER
979 	 * they should retry at PARTIAL, and instead it
980 	 * just would give up.  So, for medium_power to
981 	 * work at all, we need to only allow HIPM.
982 	 */
983 	rc = sata_scr_read(link, SCR_CONTROL, &scontrol);
984 	if (rc)
985 		return rc;
986 
987 	switch (policy) {
988 	case MIN_POWER:
989 		/* no restrictions on IPM transitions */
990 		scontrol &= ~(0x3 << 8);
991 		rc = sata_scr_write(link, SCR_CONTROL, scontrol);
992 		if (rc)
993 			return rc;
994 
995 		/* enable DIPM */
996 		if (dev->flags & ATA_DFLAG_DIPM)
997 			err_mask = ata_dev_set_feature(dev,
998 					SETFEATURES_SATA_ENABLE, SATA_DIPM);
999 		break;
1000 	case MEDIUM_POWER:
1001 		/* allow IPM to PARTIAL */
1002 		scontrol &= ~(0x1 << 8);
1003 		scontrol |= (0x2 << 8);
1004 		rc = sata_scr_write(link, SCR_CONTROL, scontrol);
1005 		if (rc)
1006 			return rc;
1007 
1008 		/*
1009 		 * we don't have to disable DIPM since IPM flags
1010 		 * disallow transitions to SLUMBER, which effectively
1011 		 * disable DIPM if it does not support PARTIAL
1012 		 */
1013 		break;
1014 	case NOT_AVAILABLE:
1015 	case MAX_PERFORMANCE:
1016 		/* disable all IPM transitions */
1017 		scontrol |= (0x3 << 8);
1018 		rc = sata_scr_write(link, SCR_CONTROL, scontrol);
1019 		if (rc)
1020 			return rc;
1021 
1022 		/*
1023 		 * we don't have to disable DIPM since IPM flags
1024 		 * disallow all transitions which effectively
1025 		 * disable DIPM anyway.
1026 		 */
1027 		break;
1028 	}
1029 
1030 	/* FIXME: handle SET FEATURES failure */
1031 	(void) err_mask;
1032 
1033 	return 0;
1034 }
1035 
1036 /**
1037  *	ata_dev_enable_pm - enable SATA interface power management
1038  *	@dev:  device to enable power management
1039  *	@policy: the link power management policy
1040  *
1041  *	Enable SATA Interface power management.  This will enable
1042  *	Device Interface Power Management (DIPM) for min_power
1043  * 	policy, and then call driver specific callbacks for
1044  *	enabling Host Initiated Power management.
1045  *
1046  *	Locking: Caller.
1047  *	Returns: -EINVAL if IPM is not supported, 0 otherwise.
1048  */
1049 void ata_dev_enable_pm(struct ata_device *dev, enum link_pm policy)
1050 {
1051 	int rc = 0;
1052 	struct ata_port *ap = dev->link->ap;
1053 
1054 	/* set HIPM first, then DIPM */
1055 	if (ap->ops->enable_pm)
1056 		rc = ap->ops->enable_pm(ap, policy);
1057 	if (rc)
1058 		goto enable_pm_out;
1059 	rc = ata_dev_set_dipm(dev, policy);
1060 
1061 enable_pm_out:
1062 	if (rc)
1063 		ap->pm_policy = MAX_PERFORMANCE;
1064 	else
1065 		ap->pm_policy = policy;
1066 	return /* rc */;	/* hopefully we can use 'rc' eventually */
1067 }
1068 
1069 #ifdef CONFIG_PM
1070 /**
1071  *	ata_dev_disable_pm - disable SATA interface power management
1072  *	@dev: device to disable power management
1073  *
1074  *	Disable SATA Interface power management.  This will disable
1075  *	Device Interface Power Management (DIPM) without changing
1076  * 	policy,  call driver specific callbacks for disabling Host
1077  * 	Initiated Power management.
1078  *
1079  *	Locking: Caller.
1080  *	Returns: void
1081  */
1082 static void ata_dev_disable_pm(struct ata_device *dev)
1083 {
1084 	struct ata_port *ap = dev->link->ap;
1085 
1086 	ata_dev_set_dipm(dev, MAX_PERFORMANCE);
1087 	if (ap->ops->disable_pm)
1088 		ap->ops->disable_pm(ap);
1089 }
1090 #endif	/* CONFIG_PM */
1091 
1092 void ata_lpm_schedule(struct ata_port *ap, enum link_pm policy)
1093 {
1094 	ap->pm_policy = policy;
1095 	ap->link.eh_info.action |= ATA_EH_LPM;
1096 	ap->link.eh_info.flags |= ATA_EHI_NO_AUTOPSY;
1097 	ata_port_schedule_eh(ap);
1098 }
1099 
1100 #ifdef CONFIG_PM
1101 static void ata_lpm_enable(struct ata_host *host)
1102 {
1103 	struct ata_link *link;
1104 	struct ata_port *ap;
1105 	struct ata_device *dev;
1106 	int i;
1107 
1108 	for (i = 0; i < host->n_ports; i++) {
1109 		ap = host->ports[i];
1110 		ata_port_for_each_link(link, ap) {
1111 			ata_link_for_each_dev(dev, link)
1112 				ata_dev_disable_pm(dev);
1113 		}
1114 	}
1115 }
1116 
1117 static void ata_lpm_disable(struct ata_host *host)
1118 {
1119 	int i;
1120 
1121 	for (i = 0; i < host->n_ports; i++) {
1122 		struct ata_port *ap = host->ports[i];
1123 		ata_lpm_schedule(ap, ap->pm_policy);
1124 	}
1125 }
1126 #endif	/* CONFIG_PM */
1127 
1128 /**
1129  *	ata_dev_classify - determine device type based on ATA-spec signature
1130  *	@tf: ATA taskfile register set for device to be identified
1131  *
1132  *	Determine from taskfile register contents whether a device is
1133  *	ATA or ATAPI, as per "Signature and persistence" section
1134  *	of ATA/PI spec (volume 1, sect 5.14).
1135  *
1136  *	LOCKING:
1137  *	None.
1138  *
1139  *	RETURNS:
1140  *	Device type, %ATA_DEV_ATA, %ATA_DEV_ATAPI, %ATA_DEV_PMP or
1141  *	%ATA_DEV_UNKNOWN the event of failure.
1142  */
1143 unsigned int ata_dev_classify(const struct ata_taskfile *tf)
1144 {
1145 	/* Apple's open source Darwin code hints that some devices only
1146 	 * put a proper signature into the LBA mid/high registers,
1147 	 * So, we only check those.  It's sufficient for uniqueness.
1148 	 *
1149 	 * ATA/ATAPI-7 (d1532v1r1: Feb. 19, 2003) specified separate
1150 	 * signatures for ATA and ATAPI devices attached on SerialATA,
1151 	 * 0x3c/0xc3 and 0x69/0x96 respectively.  However, SerialATA
1152 	 * spec has never mentioned about using different signatures
1153 	 * for ATA/ATAPI devices.  Then, Serial ATA II: Port
1154 	 * Multiplier specification began to use 0x69/0x96 to identify
1155 	 * port multpliers and 0x3c/0xc3 to identify SEMB device.
1156 	 * ATA/ATAPI-7 dropped descriptions about 0x3c/0xc3 and
1157 	 * 0x69/0x96 shortly and described them as reserved for
1158 	 * SerialATA.
1159 	 *
1160 	 * We follow the current spec and consider that 0x69/0x96
1161 	 * identifies a port multiplier and 0x3c/0xc3 a SEMB device.
1162 	 */
1163 	if ((tf->lbam == 0) && (tf->lbah == 0)) {
1164 		DPRINTK("found ATA device by sig\n");
1165 		return ATA_DEV_ATA;
1166 	}
1167 
1168 	if ((tf->lbam == 0x14) && (tf->lbah == 0xeb)) {
1169 		DPRINTK("found ATAPI device by sig\n");
1170 		return ATA_DEV_ATAPI;
1171 	}
1172 
1173 	if ((tf->lbam == 0x69) && (tf->lbah == 0x96)) {
1174 		DPRINTK("found PMP device by sig\n");
1175 		return ATA_DEV_PMP;
1176 	}
1177 
1178 	if ((tf->lbam == 0x3c) && (tf->lbah == 0xc3)) {
1179 		printk(KERN_INFO "ata: SEMB device ignored\n");
1180 		return ATA_DEV_SEMB_UNSUP; /* not yet */
1181 	}
1182 
1183 	DPRINTK("unknown device\n");
1184 	return ATA_DEV_UNKNOWN;
1185 }
1186 
1187 /**
1188  *	ata_id_string - Convert IDENTIFY DEVICE page into string
1189  *	@id: IDENTIFY DEVICE results we will examine
1190  *	@s: string into which data is output
1191  *	@ofs: offset into identify device page
1192  *	@len: length of string to return. must be an even number.
1193  *
1194  *	The strings in the IDENTIFY DEVICE page are broken up into
1195  *	16-bit chunks.  Run through the string, and output each
1196  *	8-bit chunk linearly, regardless of platform.
1197  *
1198  *	LOCKING:
1199  *	caller.
1200  */
1201 
1202 void ata_id_string(const u16 *id, unsigned char *s,
1203 		   unsigned int ofs, unsigned int len)
1204 {
1205 	unsigned int c;
1206 
1207 	BUG_ON(len & 1);
1208 
1209 	while (len > 0) {
1210 		c = id[ofs] >> 8;
1211 		*s = c;
1212 		s++;
1213 
1214 		c = id[ofs] & 0xff;
1215 		*s = c;
1216 		s++;
1217 
1218 		ofs++;
1219 		len -= 2;
1220 	}
1221 }
1222 
1223 /**
1224  *	ata_id_c_string - Convert IDENTIFY DEVICE page into C string
1225  *	@id: IDENTIFY DEVICE results we will examine
1226  *	@s: string into which data is output
1227  *	@ofs: offset into identify device page
1228  *	@len: length of string to return. must be an odd number.
1229  *
1230  *	This function is identical to ata_id_string except that it
1231  *	trims trailing spaces and terminates the resulting string with
1232  *	null.  @len must be actual maximum length (even number) + 1.
1233  *
1234  *	LOCKING:
1235  *	caller.
1236  */
1237 void ata_id_c_string(const u16 *id, unsigned char *s,
1238 		     unsigned int ofs, unsigned int len)
1239 {
1240 	unsigned char *p;
1241 
1242 	ata_id_string(id, s, ofs, len - 1);
1243 
1244 	p = s + strnlen(s, len - 1);
1245 	while (p > s && p[-1] == ' ')
1246 		p--;
1247 	*p = '\0';
1248 }
1249 
1250 static u64 ata_id_n_sectors(const u16 *id)
1251 {
1252 	if (ata_id_has_lba(id)) {
1253 		if (ata_id_has_lba48(id))
1254 			return ata_id_u64(id, 100);
1255 		else
1256 			return ata_id_u32(id, 60);
1257 	} else {
1258 		if (ata_id_current_chs_valid(id))
1259 			return ata_id_u32(id, 57);
1260 		else
1261 			return id[1] * id[3] * id[6];
1262 	}
1263 }
1264 
1265 u64 ata_tf_to_lba48(const struct ata_taskfile *tf)
1266 {
1267 	u64 sectors = 0;
1268 
1269 	sectors |= ((u64)(tf->hob_lbah & 0xff)) << 40;
1270 	sectors |= ((u64)(tf->hob_lbam & 0xff)) << 32;
1271 	sectors |= ((u64)(tf->hob_lbal & 0xff)) << 24;
1272 	sectors |= (tf->lbah & 0xff) << 16;
1273 	sectors |= (tf->lbam & 0xff) << 8;
1274 	sectors |= (tf->lbal & 0xff);
1275 
1276 	return sectors;
1277 }
1278 
1279 u64 ata_tf_to_lba(const struct ata_taskfile *tf)
1280 {
1281 	u64 sectors = 0;
1282 
1283 	sectors |= (tf->device & 0x0f) << 24;
1284 	sectors |= (tf->lbah & 0xff) << 16;
1285 	sectors |= (tf->lbam & 0xff) << 8;
1286 	sectors |= (tf->lbal & 0xff);
1287 
1288 	return sectors;
1289 }
1290 
1291 /**
1292  *	ata_read_native_max_address - Read native max address
1293  *	@dev: target device
1294  *	@max_sectors: out parameter for the result native max address
1295  *
1296  *	Perform an LBA48 or LBA28 native size query upon the device in
1297  *	question.
1298  *
1299  *	RETURNS:
1300  *	0 on success, -EACCES if command is aborted by the drive.
1301  *	-EIO on other errors.
1302  */
1303 static int ata_read_native_max_address(struct ata_device *dev, u64 *max_sectors)
1304 {
1305 	unsigned int err_mask;
1306 	struct ata_taskfile tf;
1307 	int lba48 = ata_id_has_lba48(dev->id);
1308 
1309 	ata_tf_init(dev, &tf);
1310 
1311 	/* always clear all address registers */
1312 	tf.flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
1313 
1314 	if (lba48) {
1315 		tf.command = ATA_CMD_READ_NATIVE_MAX_EXT;
1316 		tf.flags |= ATA_TFLAG_LBA48;
1317 	} else
1318 		tf.command = ATA_CMD_READ_NATIVE_MAX;
1319 
1320 	tf.protocol |= ATA_PROT_NODATA;
1321 	tf.device |= ATA_LBA;
1322 
1323 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
1324 	if (err_mask) {
1325 		ata_dev_printk(dev, KERN_WARNING, "failed to read native "
1326 			       "max address (err_mask=0x%x)\n", err_mask);
1327 		if (err_mask == AC_ERR_DEV && (tf.feature & ATA_ABORTED))
1328 			return -EACCES;
1329 		return -EIO;
1330 	}
1331 
1332 	if (lba48)
1333 		*max_sectors = ata_tf_to_lba48(&tf) + 1;
1334 	else
1335 		*max_sectors = ata_tf_to_lba(&tf) + 1;
1336 	if (dev->horkage & ATA_HORKAGE_HPA_SIZE)
1337 		(*max_sectors)--;
1338 	return 0;
1339 }
1340 
1341 /**
1342  *	ata_set_max_sectors - Set max sectors
1343  *	@dev: target device
1344  *	@new_sectors: new max sectors value to set for the device
1345  *
1346  *	Set max sectors of @dev to @new_sectors.
1347  *
1348  *	RETURNS:
1349  *	0 on success, -EACCES if command is aborted or denied (due to
1350  *	previous non-volatile SET_MAX) by the drive.  -EIO on other
1351  *	errors.
1352  */
1353 static int ata_set_max_sectors(struct ata_device *dev, u64 new_sectors)
1354 {
1355 	unsigned int err_mask;
1356 	struct ata_taskfile tf;
1357 	int lba48 = ata_id_has_lba48(dev->id);
1358 
1359 	new_sectors--;
1360 
1361 	ata_tf_init(dev, &tf);
1362 
1363 	tf.flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
1364 
1365 	if (lba48) {
1366 		tf.command = ATA_CMD_SET_MAX_EXT;
1367 		tf.flags |= ATA_TFLAG_LBA48;
1368 
1369 		tf.hob_lbal = (new_sectors >> 24) & 0xff;
1370 		tf.hob_lbam = (new_sectors >> 32) & 0xff;
1371 		tf.hob_lbah = (new_sectors >> 40) & 0xff;
1372 	} else {
1373 		tf.command = ATA_CMD_SET_MAX;
1374 
1375 		tf.device |= (new_sectors >> 24) & 0xf;
1376 	}
1377 
1378 	tf.protocol |= ATA_PROT_NODATA;
1379 	tf.device |= ATA_LBA;
1380 
1381 	tf.lbal = (new_sectors >> 0) & 0xff;
1382 	tf.lbam = (new_sectors >> 8) & 0xff;
1383 	tf.lbah = (new_sectors >> 16) & 0xff;
1384 
1385 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
1386 	if (err_mask) {
1387 		ata_dev_printk(dev, KERN_WARNING, "failed to set "
1388 			       "max address (err_mask=0x%x)\n", err_mask);
1389 		if (err_mask == AC_ERR_DEV &&
1390 		    (tf.feature & (ATA_ABORTED | ATA_IDNF)))
1391 			return -EACCES;
1392 		return -EIO;
1393 	}
1394 
1395 	return 0;
1396 }
1397 
1398 /**
1399  *	ata_hpa_resize		-	Resize a device with an HPA set
1400  *	@dev: Device to resize
1401  *
1402  *	Read the size of an LBA28 or LBA48 disk with HPA features and resize
1403  *	it if required to the full size of the media. The caller must check
1404  *	the drive has the HPA feature set enabled.
1405  *
1406  *	RETURNS:
1407  *	0 on success, -errno on failure.
1408  */
1409 static int ata_hpa_resize(struct ata_device *dev)
1410 {
1411 	struct ata_eh_context *ehc = &dev->link->eh_context;
1412 	int print_info = ehc->i.flags & ATA_EHI_PRINTINFO;
1413 	u64 sectors = ata_id_n_sectors(dev->id);
1414 	u64 native_sectors;
1415 	int rc;
1416 
1417 	/* do we need to do it? */
1418 	if (dev->class != ATA_DEV_ATA ||
1419 	    !ata_id_has_lba(dev->id) || !ata_id_hpa_enabled(dev->id) ||
1420 	    (dev->horkage & ATA_HORKAGE_BROKEN_HPA))
1421 		return 0;
1422 
1423 	/* read native max address */
1424 	rc = ata_read_native_max_address(dev, &native_sectors);
1425 	if (rc) {
1426 		/* If device aborted the command or HPA isn't going to
1427 		 * be unlocked, skip HPA resizing.
1428 		 */
1429 		if (rc == -EACCES || !ata_ignore_hpa) {
1430 			ata_dev_printk(dev, KERN_WARNING, "HPA support seems "
1431 				       "broken, skipping HPA handling\n");
1432 			dev->horkage |= ATA_HORKAGE_BROKEN_HPA;
1433 
1434 			/* we can continue if device aborted the command */
1435 			if (rc == -EACCES)
1436 				rc = 0;
1437 		}
1438 
1439 		return rc;
1440 	}
1441 
1442 	/* nothing to do? */
1443 	if (native_sectors <= sectors || !ata_ignore_hpa) {
1444 		if (!print_info || native_sectors == sectors)
1445 			return 0;
1446 
1447 		if (native_sectors > sectors)
1448 			ata_dev_printk(dev, KERN_INFO,
1449 				"HPA detected: current %llu, native %llu\n",
1450 				(unsigned long long)sectors,
1451 				(unsigned long long)native_sectors);
1452 		else if (native_sectors < sectors)
1453 			ata_dev_printk(dev, KERN_WARNING,
1454 				"native sectors (%llu) is smaller than "
1455 				"sectors (%llu)\n",
1456 				(unsigned long long)native_sectors,
1457 				(unsigned long long)sectors);
1458 		return 0;
1459 	}
1460 
1461 	/* let's unlock HPA */
1462 	rc = ata_set_max_sectors(dev, native_sectors);
1463 	if (rc == -EACCES) {
1464 		/* if device aborted the command, skip HPA resizing */
1465 		ata_dev_printk(dev, KERN_WARNING, "device aborted resize "
1466 			       "(%llu -> %llu), skipping HPA handling\n",
1467 			       (unsigned long long)sectors,
1468 			       (unsigned long long)native_sectors);
1469 		dev->horkage |= ATA_HORKAGE_BROKEN_HPA;
1470 		return 0;
1471 	} else if (rc)
1472 		return rc;
1473 
1474 	/* re-read IDENTIFY data */
1475 	rc = ata_dev_reread_id(dev, 0);
1476 	if (rc) {
1477 		ata_dev_printk(dev, KERN_ERR, "failed to re-read IDENTIFY "
1478 			       "data after HPA resizing\n");
1479 		return rc;
1480 	}
1481 
1482 	if (print_info) {
1483 		u64 new_sectors = ata_id_n_sectors(dev->id);
1484 		ata_dev_printk(dev, KERN_INFO,
1485 			"HPA unlocked: %llu -> %llu, native %llu\n",
1486 			(unsigned long long)sectors,
1487 			(unsigned long long)new_sectors,
1488 			(unsigned long long)native_sectors);
1489 	}
1490 
1491 	return 0;
1492 }
1493 
1494 /**
1495  *	ata_dump_id - IDENTIFY DEVICE info debugging output
1496  *	@id: IDENTIFY DEVICE page to dump
1497  *
1498  *	Dump selected 16-bit words from the given IDENTIFY DEVICE
1499  *	page.
1500  *
1501  *	LOCKING:
1502  *	caller.
1503  */
1504 
1505 static inline void ata_dump_id(const u16 *id)
1506 {
1507 	DPRINTK("49==0x%04x  "
1508 		"53==0x%04x  "
1509 		"63==0x%04x  "
1510 		"64==0x%04x  "
1511 		"75==0x%04x  \n",
1512 		id[49],
1513 		id[53],
1514 		id[63],
1515 		id[64],
1516 		id[75]);
1517 	DPRINTK("80==0x%04x  "
1518 		"81==0x%04x  "
1519 		"82==0x%04x  "
1520 		"83==0x%04x  "
1521 		"84==0x%04x  \n",
1522 		id[80],
1523 		id[81],
1524 		id[82],
1525 		id[83],
1526 		id[84]);
1527 	DPRINTK("88==0x%04x  "
1528 		"93==0x%04x\n",
1529 		id[88],
1530 		id[93]);
1531 }
1532 
1533 /**
1534  *	ata_id_xfermask - Compute xfermask from the given IDENTIFY data
1535  *	@id: IDENTIFY data to compute xfer mask from
1536  *
1537  *	Compute the xfermask for this device. This is not as trivial
1538  *	as it seems if we must consider early devices correctly.
1539  *
1540  *	FIXME: pre IDE drive timing (do we care ?).
1541  *
1542  *	LOCKING:
1543  *	None.
1544  *
1545  *	RETURNS:
1546  *	Computed xfermask
1547  */
1548 unsigned long ata_id_xfermask(const u16 *id)
1549 {
1550 	unsigned long pio_mask, mwdma_mask, udma_mask;
1551 
1552 	/* Usual case. Word 53 indicates word 64 is valid */
1553 	if (id[ATA_ID_FIELD_VALID] & (1 << 1)) {
1554 		pio_mask = id[ATA_ID_PIO_MODES] & 0x03;
1555 		pio_mask <<= 3;
1556 		pio_mask |= 0x7;
1557 	} else {
1558 		/* If word 64 isn't valid then Word 51 high byte holds
1559 		 * the PIO timing number for the maximum. Turn it into
1560 		 * a mask.
1561 		 */
1562 		u8 mode = (id[ATA_ID_OLD_PIO_MODES] >> 8) & 0xFF;
1563 		if (mode < 5)	/* Valid PIO range */
1564 			pio_mask = (2 << mode) - 1;
1565 		else
1566 			pio_mask = 1;
1567 
1568 		/* But wait.. there's more. Design your standards by
1569 		 * committee and you too can get a free iordy field to
1570 		 * process. However its the speeds not the modes that
1571 		 * are supported... Note drivers using the timing API
1572 		 * will get this right anyway
1573 		 */
1574 	}
1575 
1576 	mwdma_mask = id[ATA_ID_MWDMA_MODES] & 0x07;
1577 
1578 	if (ata_id_is_cfa(id)) {
1579 		/*
1580 		 *	Process compact flash extended modes
1581 		 */
1582 		int pio = id[163] & 0x7;
1583 		int dma = (id[163] >> 3) & 7;
1584 
1585 		if (pio)
1586 			pio_mask |= (1 << 5);
1587 		if (pio > 1)
1588 			pio_mask |= (1 << 6);
1589 		if (dma)
1590 			mwdma_mask |= (1 << 3);
1591 		if (dma > 1)
1592 			mwdma_mask |= (1 << 4);
1593 	}
1594 
1595 	udma_mask = 0;
1596 	if (id[ATA_ID_FIELD_VALID] & (1 << 2))
1597 		udma_mask = id[ATA_ID_UDMA_MODES] & 0xff;
1598 
1599 	return ata_pack_xfermask(pio_mask, mwdma_mask, udma_mask);
1600 }
1601 
1602 /**
1603  *	ata_pio_queue_task - Queue port_task
1604  *	@ap: The ata_port to queue port_task for
1605  *	@data: data for @fn to use
1606  *	@delay: delay time in msecs for workqueue function
1607  *
1608  *	Schedule @fn(@data) for execution after @delay jiffies using
1609  *	port_task.  There is one port_task per port and it's the
1610  *	user(low level driver)'s responsibility to make sure that only
1611  *	one task is active at any given time.
1612  *
1613  *	libata core layer takes care of synchronization between
1614  *	port_task and EH.  ata_pio_queue_task() may be ignored for EH
1615  *	synchronization.
1616  *
1617  *	LOCKING:
1618  *	Inherited from caller.
1619  */
1620 void ata_pio_queue_task(struct ata_port *ap, void *data, unsigned long delay)
1621 {
1622 	ap->port_task_data = data;
1623 
1624 	/* may fail if ata_port_flush_task() in progress */
1625 	queue_delayed_work(ata_wq, &ap->port_task, msecs_to_jiffies(delay));
1626 }
1627 
1628 /**
1629  *	ata_port_flush_task - Flush port_task
1630  *	@ap: The ata_port to flush port_task for
1631  *
1632  *	After this function completes, port_task is guranteed not to
1633  *	be running or scheduled.
1634  *
1635  *	LOCKING:
1636  *	Kernel thread context (may sleep)
1637  */
1638 void ata_port_flush_task(struct ata_port *ap)
1639 {
1640 	DPRINTK("ENTER\n");
1641 
1642 	cancel_rearming_delayed_work(&ap->port_task);
1643 
1644 	if (ata_msg_ctl(ap))
1645 		ata_port_printk(ap, KERN_DEBUG, "%s: EXIT\n", __func__);
1646 }
1647 
1648 static void ata_qc_complete_internal(struct ata_queued_cmd *qc)
1649 {
1650 	struct completion *waiting = qc->private_data;
1651 
1652 	complete(waiting);
1653 }
1654 
1655 /**
1656  *	ata_exec_internal_sg - execute libata internal command
1657  *	@dev: Device to which the command is sent
1658  *	@tf: Taskfile registers for the command and the result
1659  *	@cdb: CDB for packet command
1660  *	@dma_dir: Data tranfer direction of the command
1661  *	@sgl: sg list for the data buffer of the command
1662  *	@n_elem: Number of sg entries
1663  *	@timeout: Timeout in msecs (0 for default)
1664  *
1665  *	Executes libata internal command with timeout.  @tf contains
1666  *	command on entry and result on return.  Timeout and error
1667  *	conditions are reported via return value.  No recovery action
1668  *	is taken after a command times out.  It's caller's duty to
1669  *	clean up after timeout.
1670  *
1671  *	LOCKING:
1672  *	None.  Should be called with kernel context, might sleep.
1673  *
1674  *	RETURNS:
1675  *	Zero on success, AC_ERR_* mask on failure
1676  */
1677 unsigned ata_exec_internal_sg(struct ata_device *dev,
1678 			      struct ata_taskfile *tf, const u8 *cdb,
1679 			      int dma_dir, struct scatterlist *sgl,
1680 			      unsigned int n_elem, unsigned long timeout)
1681 {
1682 	struct ata_link *link = dev->link;
1683 	struct ata_port *ap = link->ap;
1684 	u8 command = tf->command;
1685 	int auto_timeout = 0;
1686 	struct ata_queued_cmd *qc;
1687 	unsigned int tag, preempted_tag;
1688 	u32 preempted_sactive, preempted_qc_active;
1689 	int preempted_nr_active_links;
1690 	DECLARE_COMPLETION_ONSTACK(wait);
1691 	unsigned long flags;
1692 	unsigned int err_mask;
1693 	int rc;
1694 
1695 	spin_lock_irqsave(ap->lock, flags);
1696 
1697 	/* no internal command while frozen */
1698 	if (ap->pflags & ATA_PFLAG_FROZEN) {
1699 		spin_unlock_irqrestore(ap->lock, flags);
1700 		return AC_ERR_SYSTEM;
1701 	}
1702 
1703 	/* initialize internal qc */
1704 
1705 	/* XXX: Tag 0 is used for drivers with legacy EH as some
1706 	 * drivers choke if any other tag is given.  This breaks
1707 	 * ata_tag_internal() test for those drivers.  Don't use new
1708 	 * EH stuff without converting to it.
1709 	 */
1710 	if (ap->ops->error_handler)
1711 		tag = ATA_TAG_INTERNAL;
1712 	else
1713 		tag = 0;
1714 
1715 	qc = __ata_qc_from_tag(ap, tag);
1716 
1717 	qc->tag = tag;
1718 	qc->scsicmd = NULL;
1719 	qc->ap = ap;
1720 	qc->dev = dev;
1721 	ata_qc_reinit(qc);
1722 
1723 	preempted_tag = link->active_tag;
1724 	preempted_sactive = link->sactive;
1725 	preempted_qc_active = ap->qc_active;
1726 	preempted_nr_active_links = ap->nr_active_links;
1727 	link->active_tag = ATA_TAG_POISON;
1728 	link->sactive = 0;
1729 	ap->qc_active = 0;
1730 	ap->nr_active_links = 0;
1731 
1732 	/* prepare & issue qc */
1733 	qc->tf = *tf;
1734 	if (cdb)
1735 		memcpy(qc->cdb, cdb, ATAPI_CDB_LEN);
1736 	qc->flags |= ATA_QCFLAG_RESULT_TF;
1737 	qc->dma_dir = dma_dir;
1738 	if (dma_dir != DMA_NONE) {
1739 		unsigned int i, buflen = 0;
1740 		struct scatterlist *sg;
1741 
1742 		for_each_sg(sgl, sg, n_elem, i)
1743 			buflen += sg->length;
1744 
1745 		ata_sg_init(qc, sgl, n_elem);
1746 		qc->nbytes = buflen;
1747 	}
1748 
1749 	qc->private_data = &wait;
1750 	qc->complete_fn = ata_qc_complete_internal;
1751 
1752 	ata_qc_issue(qc);
1753 
1754 	spin_unlock_irqrestore(ap->lock, flags);
1755 
1756 	if (!timeout) {
1757 		if (ata_probe_timeout)
1758 			timeout = ata_probe_timeout * 1000;
1759 		else {
1760 			timeout = ata_internal_cmd_timeout(dev, command);
1761 			auto_timeout = 1;
1762 		}
1763 	}
1764 
1765 	rc = wait_for_completion_timeout(&wait, msecs_to_jiffies(timeout));
1766 
1767 	ata_port_flush_task(ap);
1768 
1769 	if (!rc) {
1770 		spin_lock_irqsave(ap->lock, flags);
1771 
1772 		/* We're racing with irq here.  If we lose, the
1773 		 * following test prevents us from completing the qc
1774 		 * twice.  If we win, the port is frozen and will be
1775 		 * cleaned up by ->post_internal_cmd().
1776 		 */
1777 		if (qc->flags & ATA_QCFLAG_ACTIVE) {
1778 			qc->err_mask |= AC_ERR_TIMEOUT;
1779 
1780 			if (ap->ops->error_handler)
1781 				ata_port_freeze(ap);
1782 			else
1783 				ata_qc_complete(qc);
1784 
1785 			if (ata_msg_warn(ap))
1786 				ata_dev_printk(dev, KERN_WARNING,
1787 					"qc timeout (cmd 0x%x)\n", command);
1788 		}
1789 
1790 		spin_unlock_irqrestore(ap->lock, flags);
1791 	}
1792 
1793 	/* do post_internal_cmd */
1794 	if (ap->ops->post_internal_cmd)
1795 		ap->ops->post_internal_cmd(qc);
1796 
1797 	/* perform minimal error analysis */
1798 	if (qc->flags & ATA_QCFLAG_FAILED) {
1799 		if (qc->result_tf.command & (ATA_ERR | ATA_DF))
1800 			qc->err_mask |= AC_ERR_DEV;
1801 
1802 		if (!qc->err_mask)
1803 			qc->err_mask |= AC_ERR_OTHER;
1804 
1805 		if (qc->err_mask & ~AC_ERR_OTHER)
1806 			qc->err_mask &= ~AC_ERR_OTHER;
1807 	}
1808 
1809 	/* finish up */
1810 	spin_lock_irqsave(ap->lock, flags);
1811 
1812 	*tf = qc->result_tf;
1813 	err_mask = qc->err_mask;
1814 
1815 	ata_qc_free(qc);
1816 	link->active_tag = preempted_tag;
1817 	link->sactive = preempted_sactive;
1818 	ap->qc_active = preempted_qc_active;
1819 	ap->nr_active_links = preempted_nr_active_links;
1820 
1821 	/* XXX - Some LLDDs (sata_mv) disable port on command failure.
1822 	 * Until those drivers are fixed, we detect the condition
1823 	 * here, fail the command with AC_ERR_SYSTEM and reenable the
1824 	 * port.
1825 	 *
1826 	 * Note that this doesn't change any behavior as internal
1827 	 * command failure results in disabling the device in the
1828 	 * higher layer for LLDDs without new reset/EH callbacks.
1829 	 *
1830 	 * Kill the following code as soon as those drivers are fixed.
1831 	 */
1832 	if (ap->flags & ATA_FLAG_DISABLED) {
1833 		err_mask |= AC_ERR_SYSTEM;
1834 		ata_port_probe(ap);
1835 	}
1836 
1837 	spin_unlock_irqrestore(ap->lock, flags);
1838 
1839 	if ((err_mask & AC_ERR_TIMEOUT) && auto_timeout)
1840 		ata_internal_cmd_timed_out(dev, command);
1841 
1842 	return err_mask;
1843 }
1844 
1845 /**
1846  *	ata_exec_internal - execute libata internal command
1847  *	@dev: Device to which the command is sent
1848  *	@tf: Taskfile registers for the command and the result
1849  *	@cdb: CDB for packet command
1850  *	@dma_dir: Data tranfer direction of the command
1851  *	@buf: Data buffer of the command
1852  *	@buflen: Length of data buffer
1853  *	@timeout: Timeout in msecs (0 for default)
1854  *
1855  *	Wrapper around ata_exec_internal_sg() which takes simple
1856  *	buffer instead of sg list.
1857  *
1858  *	LOCKING:
1859  *	None.  Should be called with kernel context, might sleep.
1860  *
1861  *	RETURNS:
1862  *	Zero on success, AC_ERR_* mask on failure
1863  */
1864 unsigned ata_exec_internal(struct ata_device *dev,
1865 			   struct ata_taskfile *tf, const u8 *cdb,
1866 			   int dma_dir, void *buf, unsigned int buflen,
1867 			   unsigned long timeout)
1868 {
1869 	struct scatterlist *psg = NULL, sg;
1870 	unsigned int n_elem = 0;
1871 
1872 	if (dma_dir != DMA_NONE) {
1873 		WARN_ON(!buf);
1874 		sg_init_one(&sg, buf, buflen);
1875 		psg = &sg;
1876 		n_elem++;
1877 	}
1878 
1879 	return ata_exec_internal_sg(dev, tf, cdb, dma_dir, psg, n_elem,
1880 				    timeout);
1881 }
1882 
1883 /**
1884  *	ata_do_simple_cmd - execute simple internal command
1885  *	@dev: Device to which the command is sent
1886  *	@cmd: Opcode to execute
1887  *
1888  *	Execute a 'simple' command, that only consists of the opcode
1889  *	'cmd' itself, without filling any other registers
1890  *
1891  *	LOCKING:
1892  *	Kernel thread context (may sleep).
1893  *
1894  *	RETURNS:
1895  *	Zero on success, AC_ERR_* mask on failure
1896  */
1897 unsigned int ata_do_simple_cmd(struct ata_device *dev, u8 cmd)
1898 {
1899 	struct ata_taskfile tf;
1900 
1901 	ata_tf_init(dev, &tf);
1902 
1903 	tf.command = cmd;
1904 	tf.flags |= ATA_TFLAG_DEVICE;
1905 	tf.protocol = ATA_PROT_NODATA;
1906 
1907 	return ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
1908 }
1909 
1910 /**
1911  *	ata_pio_need_iordy	-	check if iordy needed
1912  *	@adev: ATA device
1913  *
1914  *	Check if the current speed of the device requires IORDY. Used
1915  *	by various controllers for chip configuration.
1916  */
1917 
1918 unsigned int ata_pio_need_iordy(const struct ata_device *adev)
1919 {
1920 	/* Controller doesn't support  IORDY. Probably a pointless check
1921 	   as the caller should know this */
1922 	if (adev->link->ap->flags & ATA_FLAG_NO_IORDY)
1923 		return 0;
1924 	/* PIO3 and higher it is mandatory */
1925 	if (adev->pio_mode > XFER_PIO_2)
1926 		return 1;
1927 	/* We turn it on when possible */
1928 	if (ata_id_has_iordy(adev->id))
1929 		return 1;
1930 	return 0;
1931 }
1932 
1933 /**
1934  *	ata_pio_mask_no_iordy	-	Return the non IORDY mask
1935  *	@adev: ATA device
1936  *
1937  *	Compute the highest mode possible if we are not using iordy. Return
1938  *	-1 if no iordy mode is available.
1939  */
1940 
1941 static u32 ata_pio_mask_no_iordy(const struct ata_device *adev)
1942 {
1943 	/* If we have no drive specific rule, then PIO 2 is non IORDY */
1944 	if (adev->id[ATA_ID_FIELD_VALID] & 2) {	/* EIDE */
1945 		u16 pio = adev->id[ATA_ID_EIDE_PIO];
1946 		/* Is the speed faster than the drive allows non IORDY ? */
1947 		if (pio) {
1948 			/* This is cycle times not frequency - watch the logic! */
1949 			if (pio > 240)	/* PIO2 is 240nS per cycle */
1950 				return 3 << ATA_SHIFT_PIO;
1951 			return 7 << ATA_SHIFT_PIO;
1952 		}
1953 	}
1954 	return 3 << ATA_SHIFT_PIO;
1955 }
1956 
1957 /**
1958  *	ata_do_dev_read_id		-	default ID read method
1959  *	@dev: device
1960  *	@tf: proposed taskfile
1961  *	@id: data buffer
1962  *
1963  *	Issue the identify taskfile and hand back the buffer containing
1964  *	identify data. For some RAID controllers and for pre ATA devices
1965  *	this function is wrapped or replaced by the driver
1966  */
1967 unsigned int ata_do_dev_read_id(struct ata_device *dev,
1968 					struct ata_taskfile *tf, u16 *id)
1969 {
1970 	return ata_exec_internal(dev, tf, NULL, DMA_FROM_DEVICE,
1971 				     id, sizeof(id[0]) * ATA_ID_WORDS, 0);
1972 }
1973 
1974 /**
1975  *	ata_dev_read_id - Read ID data from the specified device
1976  *	@dev: target device
1977  *	@p_class: pointer to class of the target device (may be changed)
1978  *	@flags: ATA_READID_* flags
1979  *	@id: buffer to read IDENTIFY data into
1980  *
1981  *	Read ID data from the specified device.  ATA_CMD_ID_ATA is
1982  *	performed on ATA devices and ATA_CMD_ID_ATAPI on ATAPI
1983  *	devices.  This function also issues ATA_CMD_INIT_DEV_PARAMS
1984  *	for pre-ATA4 drives.
1985  *
1986  *	FIXME: ATA_CMD_ID_ATA is optional for early drives and right
1987  *	now we abort if we hit that case.
1988  *
1989  *	LOCKING:
1990  *	Kernel thread context (may sleep)
1991  *
1992  *	RETURNS:
1993  *	0 on success, -errno otherwise.
1994  */
1995 int ata_dev_read_id(struct ata_device *dev, unsigned int *p_class,
1996 		    unsigned int flags, u16 *id)
1997 {
1998 	struct ata_port *ap = dev->link->ap;
1999 	unsigned int class = *p_class;
2000 	struct ata_taskfile tf;
2001 	unsigned int err_mask = 0;
2002 	const char *reason;
2003 	int may_fallback = 1, tried_spinup = 0;
2004 	int rc;
2005 
2006 	if (ata_msg_ctl(ap))
2007 		ata_dev_printk(dev, KERN_DEBUG, "%s: ENTER\n", __func__);
2008 
2009 retry:
2010 	ata_tf_init(dev, &tf);
2011 
2012 	switch (class) {
2013 	case ATA_DEV_ATA:
2014 		tf.command = ATA_CMD_ID_ATA;
2015 		break;
2016 	case ATA_DEV_ATAPI:
2017 		tf.command = ATA_CMD_ID_ATAPI;
2018 		break;
2019 	default:
2020 		rc = -ENODEV;
2021 		reason = "unsupported class";
2022 		goto err_out;
2023 	}
2024 
2025 	tf.protocol = ATA_PROT_PIO;
2026 
2027 	/* Some devices choke if TF registers contain garbage.  Make
2028 	 * sure those are properly initialized.
2029 	 */
2030 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
2031 
2032 	/* Device presence detection is unreliable on some
2033 	 * controllers.  Always poll IDENTIFY if available.
2034 	 */
2035 	tf.flags |= ATA_TFLAG_POLLING;
2036 
2037 	if (ap->ops->read_id)
2038 		err_mask = ap->ops->read_id(dev, &tf, id);
2039 	else
2040 		err_mask = ata_do_dev_read_id(dev, &tf, id);
2041 
2042 	if (err_mask) {
2043 		if (err_mask & AC_ERR_NODEV_HINT) {
2044 			ata_dev_printk(dev, KERN_DEBUG,
2045 				       "NODEV after polling detection\n");
2046 			return -ENOENT;
2047 		}
2048 
2049 		if ((err_mask == AC_ERR_DEV) && (tf.feature & ATA_ABORTED)) {
2050 			/* Device or controller might have reported
2051 			 * the wrong device class.  Give a shot at the
2052 			 * other IDENTIFY if the current one is
2053 			 * aborted by the device.
2054 			 */
2055 			if (may_fallback) {
2056 				may_fallback = 0;
2057 
2058 				if (class == ATA_DEV_ATA)
2059 					class = ATA_DEV_ATAPI;
2060 				else
2061 					class = ATA_DEV_ATA;
2062 				goto retry;
2063 			}
2064 
2065 			/* Control reaches here iff the device aborted
2066 			 * both flavors of IDENTIFYs which happens
2067 			 * sometimes with phantom devices.
2068 			 */
2069 			ata_dev_printk(dev, KERN_DEBUG,
2070 				       "both IDENTIFYs aborted, assuming NODEV\n");
2071 			return -ENOENT;
2072 		}
2073 
2074 		rc = -EIO;
2075 		reason = "I/O error";
2076 		goto err_out;
2077 	}
2078 
2079 	/* Falling back doesn't make sense if ID data was read
2080 	 * successfully at least once.
2081 	 */
2082 	may_fallback = 0;
2083 
2084 	swap_buf_le16(id, ATA_ID_WORDS);
2085 
2086 	/* sanity check */
2087 	rc = -EINVAL;
2088 	reason = "device reports invalid type";
2089 
2090 	if (class == ATA_DEV_ATA) {
2091 		if (!ata_id_is_ata(id) && !ata_id_is_cfa(id))
2092 			goto err_out;
2093 	} else {
2094 		if (ata_id_is_ata(id))
2095 			goto err_out;
2096 	}
2097 
2098 	if (!tried_spinup && (id[2] == 0x37c8 || id[2] == 0x738c)) {
2099 		tried_spinup = 1;
2100 		/*
2101 		 * Drive powered-up in standby mode, and requires a specific
2102 		 * SET_FEATURES spin-up subcommand before it will accept
2103 		 * anything other than the original IDENTIFY command.
2104 		 */
2105 		err_mask = ata_dev_set_feature(dev, SETFEATURES_SPINUP, 0);
2106 		if (err_mask && id[2] != 0x738c) {
2107 			rc = -EIO;
2108 			reason = "SPINUP failed";
2109 			goto err_out;
2110 		}
2111 		/*
2112 		 * If the drive initially returned incomplete IDENTIFY info,
2113 		 * we now must reissue the IDENTIFY command.
2114 		 */
2115 		if (id[2] == 0x37c8)
2116 			goto retry;
2117 	}
2118 
2119 	if ((flags & ATA_READID_POSTRESET) && class == ATA_DEV_ATA) {
2120 		/*
2121 		 * The exact sequence expected by certain pre-ATA4 drives is:
2122 		 * SRST RESET
2123 		 * IDENTIFY (optional in early ATA)
2124 		 * INITIALIZE DEVICE PARAMETERS (later IDE and ATA)
2125 		 * anything else..
2126 		 * Some drives were very specific about that exact sequence.
2127 		 *
2128 		 * Note that ATA4 says lba is mandatory so the second check
2129 		 * shoud never trigger.
2130 		 */
2131 		if (ata_id_major_version(id) < 4 || !ata_id_has_lba(id)) {
2132 			err_mask = ata_dev_init_params(dev, id[3], id[6]);
2133 			if (err_mask) {
2134 				rc = -EIO;
2135 				reason = "INIT_DEV_PARAMS failed";
2136 				goto err_out;
2137 			}
2138 
2139 			/* current CHS translation info (id[53-58]) might be
2140 			 * changed. reread the identify device info.
2141 			 */
2142 			flags &= ~ATA_READID_POSTRESET;
2143 			goto retry;
2144 		}
2145 	}
2146 
2147 	*p_class = class;
2148 
2149 	return 0;
2150 
2151  err_out:
2152 	if (ata_msg_warn(ap))
2153 		ata_dev_printk(dev, KERN_WARNING, "failed to IDENTIFY "
2154 			       "(%s, err_mask=0x%x)\n", reason, err_mask);
2155 	return rc;
2156 }
2157 
2158 static inline u8 ata_dev_knobble(struct ata_device *dev)
2159 {
2160 	struct ata_port *ap = dev->link->ap;
2161 
2162 	if (ata_dev_blacklisted(dev) & ATA_HORKAGE_BRIDGE_OK)
2163 		return 0;
2164 
2165 	return ((ap->cbl == ATA_CBL_SATA) && (!ata_id_is_sata(dev->id)));
2166 }
2167 
2168 static void ata_dev_config_ncq(struct ata_device *dev,
2169 			       char *desc, size_t desc_sz)
2170 {
2171 	struct ata_port *ap = dev->link->ap;
2172 	int hdepth = 0, ddepth = ata_id_queue_depth(dev->id);
2173 
2174 	if (!ata_id_has_ncq(dev->id)) {
2175 		desc[0] = '\0';
2176 		return;
2177 	}
2178 	if (dev->horkage & ATA_HORKAGE_NONCQ) {
2179 		snprintf(desc, desc_sz, "NCQ (not used)");
2180 		return;
2181 	}
2182 	if (ap->flags & ATA_FLAG_NCQ) {
2183 		hdepth = min(ap->scsi_host->can_queue, ATA_MAX_QUEUE - 1);
2184 		dev->flags |= ATA_DFLAG_NCQ;
2185 	}
2186 
2187 	if (hdepth >= ddepth)
2188 		snprintf(desc, desc_sz, "NCQ (depth %d)", ddepth);
2189 	else
2190 		snprintf(desc, desc_sz, "NCQ (depth %d/%d)", hdepth, ddepth);
2191 }
2192 
2193 /**
2194  *	ata_dev_configure - Configure the specified ATA/ATAPI device
2195  *	@dev: Target device to configure
2196  *
2197  *	Configure @dev according to @dev->id.  Generic and low-level
2198  *	driver specific fixups are also applied.
2199  *
2200  *	LOCKING:
2201  *	Kernel thread context (may sleep)
2202  *
2203  *	RETURNS:
2204  *	0 on success, -errno otherwise
2205  */
2206 int ata_dev_configure(struct ata_device *dev)
2207 {
2208 	struct ata_port *ap = dev->link->ap;
2209 	struct ata_eh_context *ehc = &dev->link->eh_context;
2210 	int print_info = ehc->i.flags & ATA_EHI_PRINTINFO;
2211 	const u16 *id = dev->id;
2212 	unsigned long xfer_mask;
2213 	char revbuf[7];		/* XYZ-99\0 */
2214 	char fwrevbuf[ATA_ID_FW_REV_LEN+1];
2215 	char modelbuf[ATA_ID_PROD_LEN+1];
2216 	int rc;
2217 
2218 	if (!ata_dev_enabled(dev) && ata_msg_info(ap)) {
2219 		ata_dev_printk(dev, KERN_INFO, "%s: ENTER/EXIT -- nodev\n",
2220 			       __func__);
2221 		return 0;
2222 	}
2223 
2224 	if (ata_msg_probe(ap))
2225 		ata_dev_printk(dev, KERN_DEBUG, "%s: ENTER\n", __func__);
2226 
2227 	/* set horkage */
2228 	dev->horkage |= ata_dev_blacklisted(dev);
2229 	ata_force_horkage(dev);
2230 
2231 	if (dev->horkage & ATA_HORKAGE_DISABLE) {
2232 		ata_dev_printk(dev, KERN_INFO,
2233 			       "unsupported device, disabling\n");
2234 		ata_dev_disable(dev);
2235 		return 0;
2236 	}
2237 
2238 	if ((!atapi_enabled || (ap->flags & ATA_FLAG_NO_ATAPI)) &&
2239 	    dev->class == ATA_DEV_ATAPI) {
2240 		ata_dev_printk(dev, KERN_WARNING,
2241 			"WARNING: ATAPI is %s, device ignored.\n",
2242 			atapi_enabled ? "not supported with this driver"
2243 				      : "disabled");
2244 		ata_dev_disable(dev);
2245 		return 0;
2246 	}
2247 
2248 	/* let ACPI work its magic */
2249 	rc = ata_acpi_on_devcfg(dev);
2250 	if (rc)
2251 		return rc;
2252 
2253 	/* massage HPA, do it early as it might change IDENTIFY data */
2254 	rc = ata_hpa_resize(dev);
2255 	if (rc)
2256 		return rc;
2257 
2258 	/* print device capabilities */
2259 	if (ata_msg_probe(ap))
2260 		ata_dev_printk(dev, KERN_DEBUG,
2261 			       "%s: cfg 49:%04x 82:%04x 83:%04x 84:%04x "
2262 			       "85:%04x 86:%04x 87:%04x 88:%04x\n",
2263 			       __func__,
2264 			       id[49], id[82], id[83], id[84],
2265 			       id[85], id[86], id[87], id[88]);
2266 
2267 	/* initialize to-be-configured parameters */
2268 	dev->flags &= ~ATA_DFLAG_CFG_MASK;
2269 	dev->max_sectors = 0;
2270 	dev->cdb_len = 0;
2271 	dev->n_sectors = 0;
2272 	dev->cylinders = 0;
2273 	dev->heads = 0;
2274 	dev->sectors = 0;
2275 
2276 	/*
2277 	 * common ATA, ATAPI feature tests
2278 	 */
2279 
2280 	/* find max transfer mode; for printk only */
2281 	xfer_mask = ata_id_xfermask(id);
2282 
2283 	if (ata_msg_probe(ap))
2284 		ata_dump_id(id);
2285 
2286 	/* SCSI only uses 4-char revisions, dump full 8 chars from ATA */
2287 	ata_id_c_string(dev->id, fwrevbuf, ATA_ID_FW_REV,
2288 			sizeof(fwrevbuf));
2289 
2290 	ata_id_c_string(dev->id, modelbuf, ATA_ID_PROD,
2291 			sizeof(modelbuf));
2292 
2293 	/* ATA-specific feature tests */
2294 	if (dev->class == ATA_DEV_ATA) {
2295 		if (ata_id_is_cfa(id)) {
2296 			if (id[162] & 1) /* CPRM may make this media unusable */
2297 				ata_dev_printk(dev, KERN_WARNING,
2298 					       "supports DRM functions and may "
2299 					       "not be fully accessable.\n");
2300 			snprintf(revbuf, 7, "CFA");
2301 		} else {
2302 			snprintf(revbuf, 7, "ATA-%d", ata_id_major_version(id));
2303 			/* Warn the user if the device has TPM extensions */
2304 			if (ata_id_has_tpm(id))
2305 				ata_dev_printk(dev, KERN_WARNING,
2306 					       "supports DRM functions and may "
2307 					       "not be fully accessable.\n");
2308 		}
2309 
2310 		dev->n_sectors = ata_id_n_sectors(id);
2311 
2312 		if (dev->id[59] & 0x100)
2313 			dev->multi_count = dev->id[59] & 0xff;
2314 
2315 		if (ata_id_has_lba(id)) {
2316 			const char *lba_desc;
2317 			char ncq_desc[20];
2318 
2319 			lba_desc = "LBA";
2320 			dev->flags |= ATA_DFLAG_LBA;
2321 			if (ata_id_has_lba48(id)) {
2322 				dev->flags |= ATA_DFLAG_LBA48;
2323 				lba_desc = "LBA48";
2324 
2325 				if (dev->n_sectors >= (1UL << 28) &&
2326 				    ata_id_has_flush_ext(id))
2327 					dev->flags |= ATA_DFLAG_FLUSH_EXT;
2328 			}
2329 
2330 			/* config NCQ */
2331 			ata_dev_config_ncq(dev, ncq_desc, sizeof(ncq_desc));
2332 
2333 			/* print device info to dmesg */
2334 			if (ata_msg_drv(ap) && print_info) {
2335 				ata_dev_printk(dev, KERN_INFO,
2336 					"%s: %s, %s, max %s\n",
2337 					revbuf, modelbuf, fwrevbuf,
2338 					ata_mode_string(xfer_mask));
2339 				ata_dev_printk(dev, KERN_INFO,
2340 					"%Lu sectors, multi %u: %s %s\n",
2341 					(unsigned long long)dev->n_sectors,
2342 					dev->multi_count, lba_desc, ncq_desc);
2343 			}
2344 		} else {
2345 			/* CHS */
2346 
2347 			/* Default translation */
2348 			dev->cylinders	= id[1];
2349 			dev->heads	= id[3];
2350 			dev->sectors	= id[6];
2351 
2352 			if (ata_id_current_chs_valid(id)) {
2353 				/* Current CHS translation is valid. */
2354 				dev->cylinders = id[54];
2355 				dev->heads     = id[55];
2356 				dev->sectors   = id[56];
2357 			}
2358 
2359 			/* print device info to dmesg */
2360 			if (ata_msg_drv(ap) && print_info) {
2361 				ata_dev_printk(dev, KERN_INFO,
2362 					"%s: %s, %s, max %s\n",
2363 					revbuf,	modelbuf, fwrevbuf,
2364 					ata_mode_string(xfer_mask));
2365 				ata_dev_printk(dev, KERN_INFO,
2366 					"%Lu sectors, multi %u, CHS %u/%u/%u\n",
2367 					(unsigned long long)dev->n_sectors,
2368 					dev->multi_count, dev->cylinders,
2369 					dev->heads, dev->sectors);
2370 			}
2371 		}
2372 
2373 		dev->cdb_len = 16;
2374 	}
2375 
2376 	/* ATAPI-specific feature tests */
2377 	else if (dev->class == ATA_DEV_ATAPI) {
2378 		const char *cdb_intr_string = "";
2379 		const char *atapi_an_string = "";
2380 		const char *dma_dir_string = "";
2381 		u32 sntf;
2382 
2383 		rc = atapi_cdb_len(id);
2384 		if ((rc < 12) || (rc > ATAPI_CDB_LEN)) {
2385 			if (ata_msg_warn(ap))
2386 				ata_dev_printk(dev, KERN_WARNING,
2387 					       "unsupported CDB len\n");
2388 			rc = -EINVAL;
2389 			goto err_out_nosup;
2390 		}
2391 		dev->cdb_len = (unsigned int) rc;
2392 
2393 		/* Enable ATAPI AN if both the host and device have
2394 		 * the support.  If PMP is attached, SNTF is required
2395 		 * to enable ATAPI AN to discern between PHY status
2396 		 * changed notifications and ATAPI ANs.
2397 		 */
2398 		if ((ap->flags & ATA_FLAG_AN) && ata_id_has_atapi_AN(id) &&
2399 		    (!sata_pmp_attached(ap) ||
2400 		     sata_scr_read(&ap->link, SCR_NOTIFICATION, &sntf) == 0)) {
2401 			unsigned int err_mask;
2402 
2403 			/* issue SET feature command to turn this on */
2404 			err_mask = ata_dev_set_feature(dev,
2405 					SETFEATURES_SATA_ENABLE, SATA_AN);
2406 			if (err_mask)
2407 				ata_dev_printk(dev, KERN_ERR,
2408 					"failed to enable ATAPI AN "
2409 					"(err_mask=0x%x)\n", err_mask);
2410 			else {
2411 				dev->flags |= ATA_DFLAG_AN;
2412 				atapi_an_string = ", ATAPI AN";
2413 			}
2414 		}
2415 
2416 		if (ata_id_cdb_intr(dev->id)) {
2417 			dev->flags |= ATA_DFLAG_CDB_INTR;
2418 			cdb_intr_string = ", CDB intr";
2419 		}
2420 
2421 		if (atapi_dmadir || atapi_id_dmadir(dev->id)) {
2422 			dev->flags |= ATA_DFLAG_DMADIR;
2423 			dma_dir_string = ", DMADIR";
2424 		}
2425 
2426 		/* print device info to dmesg */
2427 		if (ata_msg_drv(ap) && print_info)
2428 			ata_dev_printk(dev, KERN_INFO,
2429 				       "ATAPI: %s, %s, max %s%s%s%s\n",
2430 				       modelbuf, fwrevbuf,
2431 				       ata_mode_string(xfer_mask),
2432 				       cdb_intr_string, atapi_an_string,
2433 				       dma_dir_string);
2434 	}
2435 
2436 	/* determine max_sectors */
2437 	dev->max_sectors = ATA_MAX_SECTORS;
2438 	if (dev->flags & ATA_DFLAG_LBA48)
2439 		dev->max_sectors = ATA_MAX_SECTORS_LBA48;
2440 
2441 	if (!(dev->horkage & ATA_HORKAGE_IPM)) {
2442 		if (ata_id_has_hipm(dev->id))
2443 			dev->flags |= ATA_DFLAG_HIPM;
2444 		if (ata_id_has_dipm(dev->id))
2445 			dev->flags |= ATA_DFLAG_DIPM;
2446 	}
2447 
2448 	/* Limit PATA drive on SATA cable bridge transfers to udma5,
2449 	   200 sectors */
2450 	if (ata_dev_knobble(dev)) {
2451 		if (ata_msg_drv(ap) && print_info)
2452 			ata_dev_printk(dev, KERN_INFO,
2453 				       "applying bridge limits\n");
2454 		dev->udma_mask &= ATA_UDMA5;
2455 		dev->max_sectors = ATA_MAX_SECTORS;
2456 	}
2457 
2458 	if ((dev->class == ATA_DEV_ATAPI) &&
2459 	    (atapi_command_packet_set(id) == TYPE_TAPE)) {
2460 		dev->max_sectors = ATA_MAX_SECTORS_TAPE;
2461 		dev->horkage |= ATA_HORKAGE_STUCK_ERR;
2462 	}
2463 
2464 	if (dev->horkage & ATA_HORKAGE_MAX_SEC_128)
2465 		dev->max_sectors = min_t(unsigned int, ATA_MAX_SECTORS_128,
2466 					 dev->max_sectors);
2467 
2468 	if (ata_dev_blacklisted(dev) & ATA_HORKAGE_IPM) {
2469 		dev->horkage |= ATA_HORKAGE_IPM;
2470 
2471 		/* reset link pm_policy for this port to no pm */
2472 		ap->pm_policy = MAX_PERFORMANCE;
2473 	}
2474 
2475 	if (ap->ops->dev_config)
2476 		ap->ops->dev_config(dev);
2477 
2478 	if (dev->horkage & ATA_HORKAGE_DIAGNOSTIC) {
2479 		/* Let the user know. We don't want to disallow opens for
2480 		   rescue purposes, or in case the vendor is just a blithering
2481 		   idiot. Do this after the dev_config call as some controllers
2482 		   with buggy firmware may want to avoid reporting false device
2483 		   bugs */
2484 
2485 		if (print_info) {
2486 			ata_dev_printk(dev, KERN_WARNING,
2487 "Drive reports diagnostics failure. This may indicate a drive\n");
2488 			ata_dev_printk(dev, KERN_WARNING,
2489 "fault or invalid emulation. Contact drive vendor for information.\n");
2490 		}
2491 	}
2492 
2493 	return 0;
2494 
2495 err_out_nosup:
2496 	if (ata_msg_probe(ap))
2497 		ata_dev_printk(dev, KERN_DEBUG,
2498 			       "%s: EXIT, err\n", __func__);
2499 	return rc;
2500 }
2501 
2502 /**
2503  *	ata_cable_40wire	-	return 40 wire cable type
2504  *	@ap: port
2505  *
2506  *	Helper method for drivers which want to hardwire 40 wire cable
2507  *	detection.
2508  */
2509 
2510 int ata_cable_40wire(struct ata_port *ap)
2511 {
2512 	return ATA_CBL_PATA40;
2513 }
2514 
2515 /**
2516  *	ata_cable_80wire	-	return 80 wire cable type
2517  *	@ap: port
2518  *
2519  *	Helper method for drivers which want to hardwire 80 wire cable
2520  *	detection.
2521  */
2522 
2523 int ata_cable_80wire(struct ata_port *ap)
2524 {
2525 	return ATA_CBL_PATA80;
2526 }
2527 
2528 /**
2529  *	ata_cable_unknown	-	return unknown PATA cable.
2530  *	@ap: port
2531  *
2532  *	Helper method for drivers which have no PATA cable detection.
2533  */
2534 
2535 int ata_cable_unknown(struct ata_port *ap)
2536 {
2537 	return ATA_CBL_PATA_UNK;
2538 }
2539 
2540 /**
2541  *	ata_cable_ignore	-	return ignored PATA cable.
2542  *	@ap: port
2543  *
2544  *	Helper method for drivers which don't use cable type to limit
2545  *	transfer mode.
2546  */
2547 int ata_cable_ignore(struct ata_port *ap)
2548 {
2549 	return ATA_CBL_PATA_IGN;
2550 }
2551 
2552 /**
2553  *	ata_cable_sata	-	return SATA cable type
2554  *	@ap: port
2555  *
2556  *	Helper method for drivers which have SATA cables
2557  */
2558 
2559 int ata_cable_sata(struct ata_port *ap)
2560 {
2561 	return ATA_CBL_SATA;
2562 }
2563 
2564 /**
2565  *	ata_bus_probe - Reset and probe ATA bus
2566  *	@ap: Bus to probe
2567  *
2568  *	Master ATA bus probing function.  Initiates a hardware-dependent
2569  *	bus reset, then attempts to identify any devices found on
2570  *	the bus.
2571  *
2572  *	LOCKING:
2573  *	PCI/etc. bus probe sem.
2574  *
2575  *	RETURNS:
2576  *	Zero on success, negative errno otherwise.
2577  */
2578 
2579 int ata_bus_probe(struct ata_port *ap)
2580 {
2581 	unsigned int classes[ATA_MAX_DEVICES];
2582 	int tries[ATA_MAX_DEVICES];
2583 	int rc;
2584 	struct ata_device *dev;
2585 
2586 	ata_port_probe(ap);
2587 
2588 	ata_link_for_each_dev(dev, &ap->link)
2589 		tries[dev->devno] = ATA_PROBE_MAX_TRIES;
2590 
2591  retry:
2592 	ata_link_for_each_dev(dev, &ap->link) {
2593 		/* If we issue an SRST then an ATA drive (not ATAPI)
2594 		 * may change configuration and be in PIO0 timing. If
2595 		 * we do a hard reset (or are coming from power on)
2596 		 * this is true for ATA or ATAPI. Until we've set a
2597 		 * suitable controller mode we should not touch the
2598 		 * bus as we may be talking too fast.
2599 		 */
2600 		dev->pio_mode = XFER_PIO_0;
2601 
2602 		/* If the controller has a pio mode setup function
2603 		 * then use it to set the chipset to rights. Don't
2604 		 * touch the DMA setup as that will be dealt with when
2605 		 * configuring devices.
2606 		 */
2607 		if (ap->ops->set_piomode)
2608 			ap->ops->set_piomode(ap, dev);
2609 	}
2610 
2611 	/* reset and determine device classes */
2612 	ap->ops->phy_reset(ap);
2613 
2614 	ata_link_for_each_dev(dev, &ap->link) {
2615 		if (!(ap->flags & ATA_FLAG_DISABLED) &&
2616 		    dev->class != ATA_DEV_UNKNOWN)
2617 			classes[dev->devno] = dev->class;
2618 		else
2619 			classes[dev->devno] = ATA_DEV_NONE;
2620 
2621 		dev->class = ATA_DEV_UNKNOWN;
2622 	}
2623 
2624 	ata_port_probe(ap);
2625 
2626 	/* read IDENTIFY page and configure devices. We have to do the identify
2627 	   specific sequence bass-ackwards so that PDIAG- is released by
2628 	   the slave device */
2629 
2630 	ata_link_for_each_dev_reverse(dev, &ap->link) {
2631 		if (tries[dev->devno])
2632 			dev->class = classes[dev->devno];
2633 
2634 		if (!ata_dev_enabled(dev))
2635 			continue;
2636 
2637 		rc = ata_dev_read_id(dev, &dev->class, ATA_READID_POSTRESET,
2638 				     dev->id);
2639 		if (rc)
2640 			goto fail;
2641 	}
2642 
2643 	/* Now ask for the cable type as PDIAG- should have been released */
2644 	if (ap->ops->cable_detect)
2645 		ap->cbl = ap->ops->cable_detect(ap);
2646 
2647 	/* We may have SATA bridge glue hiding here irrespective of the
2648 	   reported cable types and sensed types */
2649 	ata_link_for_each_dev(dev, &ap->link) {
2650 		if (!ata_dev_enabled(dev))
2651 			continue;
2652 		/* SATA drives indicate we have a bridge. We don't know which
2653 		   end of the link the bridge is which is a problem */
2654 		if (ata_id_is_sata(dev->id))
2655 			ap->cbl = ATA_CBL_SATA;
2656 	}
2657 
2658 	/* After the identify sequence we can now set up the devices. We do
2659 	   this in the normal order so that the user doesn't get confused */
2660 
2661 	ata_link_for_each_dev(dev, &ap->link) {
2662 		if (!ata_dev_enabled(dev))
2663 			continue;
2664 
2665 		ap->link.eh_context.i.flags |= ATA_EHI_PRINTINFO;
2666 		rc = ata_dev_configure(dev);
2667 		ap->link.eh_context.i.flags &= ~ATA_EHI_PRINTINFO;
2668 		if (rc)
2669 			goto fail;
2670 	}
2671 
2672 	/* configure transfer mode */
2673 	rc = ata_set_mode(&ap->link, &dev);
2674 	if (rc)
2675 		goto fail;
2676 
2677 	ata_link_for_each_dev(dev, &ap->link)
2678 		if (ata_dev_enabled(dev))
2679 			return 0;
2680 
2681 	/* no device present, disable port */
2682 	ata_port_disable(ap);
2683 	return -ENODEV;
2684 
2685  fail:
2686 	tries[dev->devno]--;
2687 
2688 	switch (rc) {
2689 	case -EINVAL:
2690 		/* eeek, something went very wrong, give up */
2691 		tries[dev->devno] = 0;
2692 		break;
2693 
2694 	case -ENODEV:
2695 		/* give it just one more chance */
2696 		tries[dev->devno] = min(tries[dev->devno], 1);
2697 	case -EIO:
2698 		if (tries[dev->devno] == 1) {
2699 			/* This is the last chance, better to slow
2700 			 * down than lose it.
2701 			 */
2702 			sata_down_spd_limit(&ap->link);
2703 			ata_down_xfermask_limit(dev, ATA_DNXFER_PIO);
2704 		}
2705 	}
2706 
2707 	if (!tries[dev->devno])
2708 		ata_dev_disable(dev);
2709 
2710 	goto retry;
2711 }
2712 
2713 /**
2714  *	ata_port_probe - Mark port as enabled
2715  *	@ap: Port for which we indicate enablement
2716  *
2717  *	Modify @ap data structure such that the system
2718  *	thinks that the entire port is enabled.
2719  *
2720  *	LOCKING: host lock, or some other form of
2721  *	serialization.
2722  */
2723 
2724 void ata_port_probe(struct ata_port *ap)
2725 {
2726 	ap->flags &= ~ATA_FLAG_DISABLED;
2727 }
2728 
2729 /**
2730  *	sata_print_link_status - Print SATA link status
2731  *	@link: SATA link to printk link status about
2732  *
2733  *	This function prints link speed and status of a SATA link.
2734  *
2735  *	LOCKING:
2736  *	None.
2737  */
2738 static void sata_print_link_status(struct ata_link *link)
2739 {
2740 	u32 sstatus, scontrol, tmp;
2741 
2742 	if (sata_scr_read(link, SCR_STATUS, &sstatus))
2743 		return;
2744 	sata_scr_read(link, SCR_CONTROL, &scontrol);
2745 
2746 	if (ata_phys_link_online(link)) {
2747 		tmp = (sstatus >> 4) & 0xf;
2748 		ata_link_printk(link, KERN_INFO,
2749 				"SATA link up %s (SStatus %X SControl %X)\n",
2750 				sata_spd_string(tmp), sstatus, scontrol);
2751 	} else {
2752 		ata_link_printk(link, KERN_INFO,
2753 				"SATA link down (SStatus %X SControl %X)\n",
2754 				sstatus, scontrol);
2755 	}
2756 }
2757 
2758 /**
2759  *	ata_dev_pair		-	return other device on cable
2760  *	@adev: device
2761  *
2762  *	Obtain the other device on the same cable, or if none is
2763  *	present NULL is returned
2764  */
2765 
2766 struct ata_device *ata_dev_pair(struct ata_device *adev)
2767 {
2768 	struct ata_link *link = adev->link;
2769 	struct ata_device *pair = &link->device[1 - adev->devno];
2770 	if (!ata_dev_enabled(pair))
2771 		return NULL;
2772 	return pair;
2773 }
2774 
2775 /**
2776  *	ata_port_disable - Disable port.
2777  *	@ap: Port to be disabled.
2778  *
2779  *	Modify @ap data structure such that the system
2780  *	thinks that the entire port is disabled, and should
2781  *	never attempt to probe or communicate with devices
2782  *	on this port.
2783  *
2784  *	LOCKING: host lock, or some other form of
2785  *	serialization.
2786  */
2787 
2788 void ata_port_disable(struct ata_port *ap)
2789 {
2790 	ap->link.device[0].class = ATA_DEV_NONE;
2791 	ap->link.device[1].class = ATA_DEV_NONE;
2792 	ap->flags |= ATA_FLAG_DISABLED;
2793 }
2794 
2795 /**
2796  *	sata_down_spd_limit - adjust SATA spd limit downward
2797  *	@link: Link to adjust SATA spd limit for
2798  *
2799  *	Adjust SATA spd limit of @link downward.  Note that this
2800  *	function only adjusts the limit.  The change must be applied
2801  *	using sata_set_spd().
2802  *
2803  *	LOCKING:
2804  *	Inherited from caller.
2805  *
2806  *	RETURNS:
2807  *	0 on success, negative errno on failure
2808  */
2809 int sata_down_spd_limit(struct ata_link *link)
2810 {
2811 	u32 sstatus, spd, mask;
2812 	int rc, highbit;
2813 
2814 	if (!sata_scr_valid(link))
2815 		return -EOPNOTSUPP;
2816 
2817 	/* If SCR can be read, use it to determine the current SPD.
2818 	 * If not, use cached value in link->sata_spd.
2819 	 */
2820 	rc = sata_scr_read(link, SCR_STATUS, &sstatus);
2821 	if (rc == 0)
2822 		spd = (sstatus >> 4) & 0xf;
2823 	else
2824 		spd = link->sata_spd;
2825 
2826 	mask = link->sata_spd_limit;
2827 	if (mask <= 1)
2828 		return -EINVAL;
2829 
2830 	/* unconditionally mask off the highest bit */
2831 	highbit = fls(mask) - 1;
2832 	mask &= ~(1 << highbit);
2833 
2834 	/* Mask off all speeds higher than or equal to the current
2835 	 * one.  Force 1.5Gbps if current SPD is not available.
2836 	 */
2837 	if (spd > 1)
2838 		mask &= (1 << (spd - 1)) - 1;
2839 	else
2840 		mask &= 1;
2841 
2842 	/* were we already at the bottom? */
2843 	if (!mask)
2844 		return -EINVAL;
2845 
2846 	link->sata_spd_limit = mask;
2847 
2848 	ata_link_printk(link, KERN_WARNING, "limiting SATA link speed to %s\n",
2849 			sata_spd_string(fls(mask)));
2850 
2851 	return 0;
2852 }
2853 
2854 static int __sata_set_spd_needed(struct ata_link *link, u32 *scontrol)
2855 {
2856 	struct ata_link *host_link = &link->ap->link;
2857 	u32 limit, target, spd;
2858 
2859 	limit = link->sata_spd_limit;
2860 
2861 	/* Don't configure downstream link faster than upstream link.
2862 	 * It doesn't speed up anything and some PMPs choke on such
2863 	 * configuration.
2864 	 */
2865 	if (!ata_is_host_link(link) && host_link->sata_spd)
2866 		limit &= (1 << host_link->sata_spd) - 1;
2867 
2868 	if (limit == UINT_MAX)
2869 		target = 0;
2870 	else
2871 		target = fls(limit);
2872 
2873 	spd = (*scontrol >> 4) & 0xf;
2874 	*scontrol = (*scontrol & ~0xf0) | ((target & 0xf) << 4);
2875 
2876 	return spd != target;
2877 }
2878 
2879 /**
2880  *	sata_set_spd_needed - is SATA spd configuration needed
2881  *	@link: Link in question
2882  *
2883  *	Test whether the spd limit in SControl matches
2884  *	@link->sata_spd_limit.  This function is used to determine
2885  *	whether hardreset is necessary to apply SATA spd
2886  *	configuration.
2887  *
2888  *	LOCKING:
2889  *	Inherited from caller.
2890  *
2891  *	RETURNS:
2892  *	1 if SATA spd configuration is needed, 0 otherwise.
2893  */
2894 static int sata_set_spd_needed(struct ata_link *link)
2895 {
2896 	u32 scontrol;
2897 
2898 	if (sata_scr_read(link, SCR_CONTROL, &scontrol))
2899 		return 1;
2900 
2901 	return __sata_set_spd_needed(link, &scontrol);
2902 }
2903 
2904 /**
2905  *	sata_set_spd - set SATA spd according to spd limit
2906  *	@link: Link to set SATA spd for
2907  *
2908  *	Set SATA spd of @link according to sata_spd_limit.
2909  *
2910  *	LOCKING:
2911  *	Inherited from caller.
2912  *
2913  *	RETURNS:
2914  *	0 if spd doesn't need to be changed, 1 if spd has been
2915  *	changed.  Negative errno if SCR registers are inaccessible.
2916  */
2917 int sata_set_spd(struct ata_link *link)
2918 {
2919 	u32 scontrol;
2920 	int rc;
2921 
2922 	if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
2923 		return rc;
2924 
2925 	if (!__sata_set_spd_needed(link, &scontrol))
2926 		return 0;
2927 
2928 	if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
2929 		return rc;
2930 
2931 	return 1;
2932 }
2933 
2934 /*
2935  * This mode timing computation functionality is ported over from
2936  * drivers/ide/ide-timing.h and was originally written by Vojtech Pavlik
2937  */
2938 /*
2939  * PIO 0-4, MWDMA 0-2 and UDMA 0-6 timings (in nanoseconds).
2940  * These were taken from ATA/ATAPI-6 standard, rev 0a, except
2941  * for UDMA6, which is currently supported only by Maxtor drives.
2942  *
2943  * For PIO 5/6 MWDMA 3/4 see the CFA specification 3.0.
2944  */
2945 
2946 static const struct ata_timing ata_timing[] = {
2947 /*	{ XFER_PIO_SLOW, 120, 290, 240, 960, 290, 240, 960,   0 }, */
2948 	{ XFER_PIO_0,     70, 290, 240, 600, 165, 150, 600,   0 },
2949 	{ XFER_PIO_1,     50, 290,  93, 383, 125, 100, 383,   0 },
2950 	{ XFER_PIO_2,     30, 290,  40, 330, 100,  90, 240,   0 },
2951 	{ XFER_PIO_3,     30,  80,  70, 180,  80,  70, 180,   0 },
2952 	{ XFER_PIO_4,     25,  70,  25, 120,  70,  25, 120,   0 },
2953 	{ XFER_PIO_5,     15,  65,  25, 100,  65,  25, 100,   0 },
2954 	{ XFER_PIO_6,     10,  55,  20,  80,  55,  20,  80,   0 },
2955 
2956 	{ XFER_SW_DMA_0, 120,   0,   0,   0, 480, 480, 960,   0 },
2957 	{ XFER_SW_DMA_1,  90,   0,   0,   0, 240, 240, 480,   0 },
2958 	{ XFER_SW_DMA_2,  60,   0,   0,   0, 120, 120, 240,   0 },
2959 
2960 	{ XFER_MW_DMA_0,  60,   0,   0,   0, 215, 215, 480,   0 },
2961 	{ XFER_MW_DMA_1,  45,   0,   0,   0,  80,  50, 150,   0 },
2962 	{ XFER_MW_DMA_2,  25,   0,   0,   0,  70,  25, 120,   0 },
2963 	{ XFER_MW_DMA_3,  25,   0,   0,   0,  65,  25, 100,   0 },
2964 	{ XFER_MW_DMA_4,  25,   0,   0,   0,  55,  20,  80,   0 },
2965 
2966 /*	{ XFER_UDMA_SLOW,  0,   0,   0,   0,   0,   0,   0, 150 }, */
2967 	{ XFER_UDMA_0,     0,   0,   0,   0,   0,   0,   0, 120 },
2968 	{ XFER_UDMA_1,     0,   0,   0,   0,   0,   0,   0,  80 },
2969 	{ XFER_UDMA_2,     0,   0,   0,   0,   0,   0,   0,  60 },
2970 	{ XFER_UDMA_3,     0,   0,   0,   0,   0,   0,   0,  45 },
2971 	{ XFER_UDMA_4,     0,   0,   0,   0,   0,   0,   0,  30 },
2972 	{ XFER_UDMA_5,     0,   0,   0,   0,   0,   0,   0,  20 },
2973 	{ XFER_UDMA_6,     0,   0,   0,   0,   0,   0,   0,  15 },
2974 
2975 	{ 0xFF }
2976 };
2977 
2978 #define ENOUGH(v, unit)		(((v)-1)/(unit)+1)
2979 #define EZ(v, unit)		((v)?ENOUGH(v, unit):0)
2980 
2981 static void ata_timing_quantize(const struct ata_timing *t, struct ata_timing *q, int T, int UT)
2982 {
2983 	q->setup   = EZ(t->setup   * 1000,  T);
2984 	q->act8b   = EZ(t->act8b   * 1000,  T);
2985 	q->rec8b   = EZ(t->rec8b   * 1000,  T);
2986 	q->cyc8b   = EZ(t->cyc8b   * 1000,  T);
2987 	q->active  = EZ(t->active  * 1000,  T);
2988 	q->recover = EZ(t->recover * 1000,  T);
2989 	q->cycle   = EZ(t->cycle   * 1000,  T);
2990 	q->udma    = EZ(t->udma    * 1000, UT);
2991 }
2992 
2993 void ata_timing_merge(const struct ata_timing *a, const struct ata_timing *b,
2994 		      struct ata_timing *m, unsigned int what)
2995 {
2996 	if (what & ATA_TIMING_SETUP  ) m->setup   = max(a->setup,   b->setup);
2997 	if (what & ATA_TIMING_ACT8B  ) m->act8b   = max(a->act8b,   b->act8b);
2998 	if (what & ATA_TIMING_REC8B  ) m->rec8b   = max(a->rec8b,   b->rec8b);
2999 	if (what & ATA_TIMING_CYC8B  ) m->cyc8b   = max(a->cyc8b,   b->cyc8b);
3000 	if (what & ATA_TIMING_ACTIVE ) m->active  = max(a->active,  b->active);
3001 	if (what & ATA_TIMING_RECOVER) m->recover = max(a->recover, b->recover);
3002 	if (what & ATA_TIMING_CYCLE  ) m->cycle   = max(a->cycle,   b->cycle);
3003 	if (what & ATA_TIMING_UDMA   ) m->udma    = max(a->udma,    b->udma);
3004 }
3005 
3006 const struct ata_timing *ata_timing_find_mode(u8 xfer_mode)
3007 {
3008 	const struct ata_timing *t = ata_timing;
3009 
3010 	while (xfer_mode > t->mode)
3011 		t++;
3012 
3013 	if (xfer_mode == t->mode)
3014 		return t;
3015 	return NULL;
3016 }
3017 
3018 int ata_timing_compute(struct ata_device *adev, unsigned short speed,
3019 		       struct ata_timing *t, int T, int UT)
3020 {
3021 	const struct ata_timing *s;
3022 	struct ata_timing p;
3023 
3024 	/*
3025 	 * Find the mode.
3026 	 */
3027 
3028 	if (!(s = ata_timing_find_mode(speed)))
3029 		return -EINVAL;
3030 
3031 	memcpy(t, s, sizeof(*s));
3032 
3033 	/*
3034 	 * If the drive is an EIDE drive, it can tell us it needs extended
3035 	 * PIO/MW_DMA cycle timing.
3036 	 */
3037 
3038 	if (adev->id[ATA_ID_FIELD_VALID] & 2) {	/* EIDE drive */
3039 		memset(&p, 0, sizeof(p));
3040 		if (speed >= XFER_PIO_0 && speed <= XFER_SW_DMA_0) {
3041 			if (speed <= XFER_PIO_2) p.cycle = p.cyc8b = adev->id[ATA_ID_EIDE_PIO];
3042 					    else p.cycle = p.cyc8b = adev->id[ATA_ID_EIDE_PIO_IORDY];
3043 		} else if (speed >= XFER_MW_DMA_0 && speed <= XFER_MW_DMA_2) {
3044 			p.cycle = adev->id[ATA_ID_EIDE_DMA_MIN];
3045 		}
3046 		ata_timing_merge(&p, t, t, ATA_TIMING_CYCLE | ATA_TIMING_CYC8B);
3047 	}
3048 
3049 	/*
3050 	 * Convert the timing to bus clock counts.
3051 	 */
3052 
3053 	ata_timing_quantize(t, t, T, UT);
3054 
3055 	/*
3056 	 * Even in DMA/UDMA modes we still use PIO access for IDENTIFY,
3057 	 * S.M.A.R.T * and some other commands. We have to ensure that the
3058 	 * DMA cycle timing is slower/equal than the fastest PIO timing.
3059 	 */
3060 
3061 	if (speed > XFER_PIO_6) {
3062 		ata_timing_compute(adev, adev->pio_mode, &p, T, UT);
3063 		ata_timing_merge(&p, t, t, ATA_TIMING_ALL);
3064 	}
3065 
3066 	/*
3067 	 * Lengthen active & recovery time so that cycle time is correct.
3068 	 */
3069 
3070 	if (t->act8b + t->rec8b < t->cyc8b) {
3071 		t->act8b += (t->cyc8b - (t->act8b + t->rec8b)) / 2;
3072 		t->rec8b = t->cyc8b - t->act8b;
3073 	}
3074 
3075 	if (t->active + t->recover < t->cycle) {
3076 		t->active += (t->cycle - (t->active + t->recover)) / 2;
3077 		t->recover = t->cycle - t->active;
3078 	}
3079 
3080 	/* In a few cases quantisation may produce enough errors to
3081 	   leave t->cycle too low for the sum of active and recovery
3082 	   if so we must correct this */
3083 	if (t->active + t->recover > t->cycle)
3084 		t->cycle = t->active + t->recover;
3085 
3086 	return 0;
3087 }
3088 
3089 /**
3090  *	ata_timing_cycle2mode - find xfer mode for the specified cycle duration
3091  *	@xfer_shift: ATA_SHIFT_* value for transfer type to examine.
3092  *	@cycle: cycle duration in ns
3093  *
3094  *	Return matching xfer mode for @cycle.  The returned mode is of
3095  *	the transfer type specified by @xfer_shift.  If @cycle is too
3096  *	slow for @xfer_shift, 0xff is returned.  If @cycle is faster
3097  *	than the fastest known mode, the fasted mode is returned.
3098  *
3099  *	LOCKING:
3100  *	None.
3101  *
3102  *	RETURNS:
3103  *	Matching xfer_mode, 0xff if no match found.
3104  */
3105 u8 ata_timing_cycle2mode(unsigned int xfer_shift, int cycle)
3106 {
3107 	u8 base_mode = 0xff, last_mode = 0xff;
3108 	const struct ata_xfer_ent *ent;
3109 	const struct ata_timing *t;
3110 
3111 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
3112 		if (ent->shift == xfer_shift)
3113 			base_mode = ent->base;
3114 
3115 	for (t = ata_timing_find_mode(base_mode);
3116 	     t && ata_xfer_mode2shift(t->mode) == xfer_shift; t++) {
3117 		unsigned short this_cycle;
3118 
3119 		switch (xfer_shift) {
3120 		case ATA_SHIFT_PIO:
3121 		case ATA_SHIFT_MWDMA:
3122 			this_cycle = t->cycle;
3123 			break;
3124 		case ATA_SHIFT_UDMA:
3125 			this_cycle = t->udma;
3126 			break;
3127 		default:
3128 			return 0xff;
3129 		}
3130 
3131 		if (cycle > this_cycle)
3132 			break;
3133 
3134 		last_mode = t->mode;
3135 	}
3136 
3137 	return last_mode;
3138 }
3139 
3140 /**
3141  *	ata_down_xfermask_limit - adjust dev xfer masks downward
3142  *	@dev: Device to adjust xfer masks
3143  *	@sel: ATA_DNXFER_* selector
3144  *
3145  *	Adjust xfer masks of @dev downward.  Note that this function
3146  *	does not apply the change.  Invoking ata_set_mode() afterwards
3147  *	will apply the limit.
3148  *
3149  *	LOCKING:
3150  *	Inherited from caller.
3151  *
3152  *	RETURNS:
3153  *	0 on success, negative errno on failure
3154  */
3155 int ata_down_xfermask_limit(struct ata_device *dev, unsigned int sel)
3156 {
3157 	char buf[32];
3158 	unsigned long orig_mask, xfer_mask;
3159 	unsigned long pio_mask, mwdma_mask, udma_mask;
3160 	int quiet, highbit;
3161 
3162 	quiet = !!(sel & ATA_DNXFER_QUIET);
3163 	sel &= ~ATA_DNXFER_QUIET;
3164 
3165 	xfer_mask = orig_mask = ata_pack_xfermask(dev->pio_mask,
3166 						  dev->mwdma_mask,
3167 						  dev->udma_mask);
3168 	ata_unpack_xfermask(xfer_mask, &pio_mask, &mwdma_mask, &udma_mask);
3169 
3170 	switch (sel) {
3171 	case ATA_DNXFER_PIO:
3172 		highbit = fls(pio_mask) - 1;
3173 		pio_mask &= ~(1 << highbit);
3174 		break;
3175 
3176 	case ATA_DNXFER_DMA:
3177 		if (udma_mask) {
3178 			highbit = fls(udma_mask) - 1;
3179 			udma_mask &= ~(1 << highbit);
3180 			if (!udma_mask)
3181 				return -ENOENT;
3182 		} else if (mwdma_mask) {
3183 			highbit = fls(mwdma_mask) - 1;
3184 			mwdma_mask &= ~(1 << highbit);
3185 			if (!mwdma_mask)
3186 				return -ENOENT;
3187 		}
3188 		break;
3189 
3190 	case ATA_DNXFER_40C:
3191 		udma_mask &= ATA_UDMA_MASK_40C;
3192 		break;
3193 
3194 	case ATA_DNXFER_FORCE_PIO0:
3195 		pio_mask &= 1;
3196 	case ATA_DNXFER_FORCE_PIO:
3197 		mwdma_mask = 0;
3198 		udma_mask = 0;
3199 		break;
3200 
3201 	default:
3202 		BUG();
3203 	}
3204 
3205 	xfer_mask &= ata_pack_xfermask(pio_mask, mwdma_mask, udma_mask);
3206 
3207 	if (!(xfer_mask & ATA_MASK_PIO) || xfer_mask == orig_mask)
3208 		return -ENOENT;
3209 
3210 	if (!quiet) {
3211 		if (xfer_mask & (ATA_MASK_MWDMA | ATA_MASK_UDMA))
3212 			snprintf(buf, sizeof(buf), "%s:%s",
3213 				 ata_mode_string(xfer_mask),
3214 				 ata_mode_string(xfer_mask & ATA_MASK_PIO));
3215 		else
3216 			snprintf(buf, sizeof(buf), "%s",
3217 				 ata_mode_string(xfer_mask));
3218 
3219 		ata_dev_printk(dev, KERN_WARNING,
3220 			       "limiting speed to %s\n", buf);
3221 	}
3222 
3223 	ata_unpack_xfermask(xfer_mask, &dev->pio_mask, &dev->mwdma_mask,
3224 			    &dev->udma_mask);
3225 
3226 	return 0;
3227 }
3228 
3229 static int ata_dev_set_mode(struct ata_device *dev)
3230 {
3231 	struct ata_eh_context *ehc = &dev->link->eh_context;
3232 	const char *dev_err_whine = "";
3233 	int ign_dev_err = 0;
3234 	unsigned int err_mask;
3235 	int rc;
3236 
3237 	dev->flags &= ~ATA_DFLAG_PIO;
3238 	if (dev->xfer_shift == ATA_SHIFT_PIO)
3239 		dev->flags |= ATA_DFLAG_PIO;
3240 
3241 	err_mask = ata_dev_set_xfermode(dev);
3242 
3243 	if (err_mask & ~AC_ERR_DEV)
3244 		goto fail;
3245 
3246 	/* revalidate */
3247 	ehc->i.flags |= ATA_EHI_POST_SETMODE;
3248 	rc = ata_dev_revalidate(dev, ATA_DEV_UNKNOWN, 0);
3249 	ehc->i.flags &= ~ATA_EHI_POST_SETMODE;
3250 	if (rc)
3251 		return rc;
3252 
3253 	if (dev->xfer_shift == ATA_SHIFT_PIO) {
3254 		/* Old CFA may refuse this command, which is just fine */
3255 		if (ata_id_is_cfa(dev->id))
3256 			ign_dev_err = 1;
3257 		/* Catch several broken garbage emulations plus some pre
3258 		   ATA devices */
3259 		if (ata_id_major_version(dev->id) == 0 &&
3260 					dev->pio_mode <= XFER_PIO_2)
3261 			ign_dev_err = 1;
3262 		/* Some very old devices and some bad newer ones fail
3263 		   any kind of SET_XFERMODE request but support PIO0-2
3264 		   timings and no IORDY */
3265 		if (!ata_id_has_iordy(dev->id) && dev->pio_mode <= XFER_PIO_2)
3266 			ign_dev_err = 1;
3267 	}
3268 	/* Early MWDMA devices do DMA but don't allow DMA mode setting.
3269 	   Don't fail an MWDMA0 set IFF the device indicates it is in MWDMA0 */
3270 	if (dev->xfer_shift == ATA_SHIFT_MWDMA &&
3271 	    dev->dma_mode == XFER_MW_DMA_0 &&
3272 	    (dev->id[63] >> 8) & 1)
3273 		ign_dev_err = 1;
3274 
3275 	/* if the device is actually configured correctly, ignore dev err */
3276 	if (dev->xfer_mode == ata_xfer_mask2mode(ata_id_xfermask(dev->id)))
3277 		ign_dev_err = 1;
3278 
3279 	if (err_mask & AC_ERR_DEV) {
3280 		if (!ign_dev_err)
3281 			goto fail;
3282 		else
3283 			dev_err_whine = " (device error ignored)";
3284 	}
3285 
3286 	DPRINTK("xfer_shift=%u, xfer_mode=0x%x\n",
3287 		dev->xfer_shift, (int)dev->xfer_mode);
3288 
3289 	ata_dev_printk(dev, KERN_INFO, "configured for %s%s\n",
3290 		       ata_mode_string(ata_xfer_mode2mask(dev->xfer_mode)),
3291 		       dev_err_whine);
3292 
3293 	return 0;
3294 
3295  fail:
3296 	ata_dev_printk(dev, KERN_ERR, "failed to set xfermode "
3297 		       "(err_mask=0x%x)\n", err_mask);
3298 	return -EIO;
3299 }
3300 
3301 /**
3302  *	ata_do_set_mode - Program timings and issue SET FEATURES - XFER
3303  *	@link: link on which timings will be programmed
3304  *	@r_failed_dev: out parameter for failed device
3305  *
3306  *	Standard implementation of the function used to tune and set
3307  *	ATA device disk transfer mode (PIO3, UDMA6, etc.).  If
3308  *	ata_dev_set_mode() fails, pointer to the failing device is
3309  *	returned in @r_failed_dev.
3310  *
3311  *	LOCKING:
3312  *	PCI/etc. bus probe sem.
3313  *
3314  *	RETURNS:
3315  *	0 on success, negative errno otherwise
3316  */
3317 
3318 int ata_do_set_mode(struct ata_link *link, struct ata_device **r_failed_dev)
3319 {
3320 	struct ata_port *ap = link->ap;
3321 	struct ata_device *dev;
3322 	int rc = 0, used_dma = 0, found = 0;
3323 
3324 	/* step 1: calculate xfer_mask */
3325 	ata_link_for_each_dev(dev, link) {
3326 		unsigned long pio_mask, dma_mask;
3327 		unsigned int mode_mask;
3328 
3329 		if (!ata_dev_enabled(dev))
3330 			continue;
3331 
3332 		mode_mask = ATA_DMA_MASK_ATA;
3333 		if (dev->class == ATA_DEV_ATAPI)
3334 			mode_mask = ATA_DMA_MASK_ATAPI;
3335 		else if (ata_id_is_cfa(dev->id))
3336 			mode_mask = ATA_DMA_MASK_CFA;
3337 
3338 		ata_dev_xfermask(dev);
3339 		ata_force_xfermask(dev);
3340 
3341 		pio_mask = ata_pack_xfermask(dev->pio_mask, 0, 0);
3342 		dma_mask = ata_pack_xfermask(0, dev->mwdma_mask, dev->udma_mask);
3343 
3344 		if (libata_dma_mask & mode_mask)
3345 			dma_mask = ata_pack_xfermask(0, dev->mwdma_mask, dev->udma_mask);
3346 		else
3347 			dma_mask = 0;
3348 
3349 		dev->pio_mode = ata_xfer_mask2mode(pio_mask);
3350 		dev->dma_mode = ata_xfer_mask2mode(dma_mask);
3351 
3352 		found = 1;
3353 		if (ata_dma_enabled(dev))
3354 			used_dma = 1;
3355 	}
3356 	if (!found)
3357 		goto out;
3358 
3359 	/* step 2: always set host PIO timings */
3360 	ata_link_for_each_dev(dev, link) {
3361 		if (!ata_dev_enabled(dev))
3362 			continue;
3363 
3364 		if (dev->pio_mode == 0xff) {
3365 			ata_dev_printk(dev, KERN_WARNING, "no PIO support\n");
3366 			rc = -EINVAL;
3367 			goto out;
3368 		}
3369 
3370 		dev->xfer_mode = dev->pio_mode;
3371 		dev->xfer_shift = ATA_SHIFT_PIO;
3372 		if (ap->ops->set_piomode)
3373 			ap->ops->set_piomode(ap, dev);
3374 	}
3375 
3376 	/* step 3: set host DMA timings */
3377 	ata_link_for_each_dev(dev, link) {
3378 		if (!ata_dev_enabled(dev) || !ata_dma_enabled(dev))
3379 			continue;
3380 
3381 		dev->xfer_mode = dev->dma_mode;
3382 		dev->xfer_shift = ata_xfer_mode2shift(dev->dma_mode);
3383 		if (ap->ops->set_dmamode)
3384 			ap->ops->set_dmamode(ap, dev);
3385 	}
3386 
3387 	/* step 4: update devices' xfer mode */
3388 	ata_link_for_each_dev(dev, link) {
3389 		/* don't update suspended devices' xfer mode */
3390 		if (!ata_dev_enabled(dev))
3391 			continue;
3392 
3393 		rc = ata_dev_set_mode(dev);
3394 		if (rc)
3395 			goto out;
3396 	}
3397 
3398 	/* Record simplex status. If we selected DMA then the other
3399 	 * host channels are not permitted to do so.
3400 	 */
3401 	if (used_dma && (ap->host->flags & ATA_HOST_SIMPLEX))
3402 		ap->host->simplex_claimed = ap;
3403 
3404  out:
3405 	if (rc)
3406 		*r_failed_dev = dev;
3407 	return rc;
3408 }
3409 
3410 /**
3411  *	ata_wait_ready - wait for link to become ready
3412  *	@link: link to be waited on
3413  *	@deadline: deadline jiffies for the operation
3414  *	@check_ready: callback to check link readiness
3415  *
3416  *	Wait for @link to become ready.  @check_ready should return
3417  *	positive number if @link is ready, 0 if it isn't, -ENODEV if
3418  *	link doesn't seem to be occupied, other errno for other error
3419  *	conditions.
3420  *
3421  *	Transient -ENODEV conditions are allowed for
3422  *	ATA_TMOUT_FF_WAIT.
3423  *
3424  *	LOCKING:
3425  *	EH context.
3426  *
3427  *	RETURNS:
3428  *	0 if @linke is ready before @deadline; otherwise, -errno.
3429  */
3430 int ata_wait_ready(struct ata_link *link, unsigned long deadline,
3431 		   int (*check_ready)(struct ata_link *link))
3432 {
3433 	unsigned long start = jiffies;
3434 	unsigned long nodev_deadline = ata_deadline(start, ATA_TMOUT_FF_WAIT);
3435 	int warned = 0;
3436 
3437 	/* Slave readiness can't be tested separately from master.  On
3438 	 * M/S emulation configuration, this function should be called
3439 	 * only on the master and it will handle both master and slave.
3440 	 */
3441 	WARN_ON(link == link->ap->slave_link);
3442 
3443 	if (time_after(nodev_deadline, deadline))
3444 		nodev_deadline = deadline;
3445 
3446 	while (1) {
3447 		unsigned long now = jiffies;
3448 		int ready, tmp;
3449 
3450 		ready = tmp = check_ready(link);
3451 		if (ready > 0)
3452 			return 0;
3453 
3454 		/* -ENODEV could be transient.  Ignore -ENODEV if link
3455 		 * is online.  Also, some SATA devices take a long
3456 		 * time to clear 0xff after reset.  For example,
3457 		 * HHD424020F7SV00 iVDR needs >= 800ms while Quantum
3458 		 * GoVault needs even more than that.  Wait for
3459 		 * ATA_TMOUT_FF_WAIT on -ENODEV if link isn't offline.
3460 		 *
3461 		 * Note that some PATA controllers (pata_ali) explode
3462 		 * if status register is read more than once when
3463 		 * there's no device attached.
3464 		 */
3465 		if (ready == -ENODEV) {
3466 			if (ata_link_online(link))
3467 				ready = 0;
3468 			else if ((link->ap->flags & ATA_FLAG_SATA) &&
3469 				 !ata_link_offline(link) &&
3470 				 time_before(now, nodev_deadline))
3471 				ready = 0;
3472 		}
3473 
3474 		if (ready)
3475 			return ready;
3476 		if (time_after(now, deadline))
3477 			return -EBUSY;
3478 
3479 		if (!warned && time_after(now, start + 5 * HZ) &&
3480 		    (deadline - now > 3 * HZ)) {
3481 			ata_link_printk(link, KERN_WARNING,
3482 				"link is slow to respond, please be patient "
3483 				"(ready=%d)\n", tmp);
3484 			warned = 1;
3485 		}
3486 
3487 		msleep(50);
3488 	}
3489 }
3490 
3491 /**
3492  *	ata_wait_after_reset - wait for link to become ready after reset
3493  *	@link: link to be waited on
3494  *	@deadline: deadline jiffies for the operation
3495  *	@check_ready: callback to check link readiness
3496  *
3497  *	Wait for @link to become ready after reset.
3498  *
3499  *	LOCKING:
3500  *	EH context.
3501  *
3502  *	RETURNS:
3503  *	0 if @linke is ready before @deadline; otherwise, -errno.
3504  */
3505 int ata_wait_after_reset(struct ata_link *link, unsigned long deadline,
3506 				int (*check_ready)(struct ata_link *link))
3507 {
3508 	msleep(ATA_WAIT_AFTER_RESET);
3509 
3510 	return ata_wait_ready(link, deadline, check_ready);
3511 }
3512 
3513 /**
3514  *	sata_link_debounce - debounce SATA phy status
3515  *	@link: ATA link to debounce SATA phy status for
3516  *	@params: timing parameters { interval, duratinon, timeout } in msec
3517  *	@deadline: deadline jiffies for the operation
3518  *
3519 *	Make sure SStatus of @link reaches stable state, determined by
3520  *	holding the same value where DET is not 1 for @duration polled
3521  *	every @interval, before @timeout.  Timeout constraints the
3522  *	beginning of the stable state.  Because DET gets stuck at 1 on
3523  *	some controllers after hot unplugging, this functions waits
3524  *	until timeout then returns 0 if DET is stable at 1.
3525  *
3526  *	@timeout is further limited by @deadline.  The sooner of the
3527  *	two is used.
3528  *
3529  *	LOCKING:
3530  *	Kernel thread context (may sleep)
3531  *
3532  *	RETURNS:
3533  *	0 on success, -errno on failure.
3534  */
3535 int sata_link_debounce(struct ata_link *link, const unsigned long *params,
3536 		       unsigned long deadline)
3537 {
3538 	unsigned long interval = params[0];
3539 	unsigned long duration = params[1];
3540 	unsigned long last_jiffies, t;
3541 	u32 last, cur;
3542 	int rc;
3543 
3544 	t = ata_deadline(jiffies, params[2]);
3545 	if (time_before(t, deadline))
3546 		deadline = t;
3547 
3548 	if ((rc = sata_scr_read(link, SCR_STATUS, &cur)))
3549 		return rc;
3550 	cur &= 0xf;
3551 
3552 	last = cur;
3553 	last_jiffies = jiffies;
3554 
3555 	while (1) {
3556 		msleep(interval);
3557 		if ((rc = sata_scr_read(link, SCR_STATUS, &cur)))
3558 			return rc;
3559 		cur &= 0xf;
3560 
3561 		/* DET stable? */
3562 		if (cur == last) {
3563 			if (cur == 1 && time_before(jiffies, deadline))
3564 				continue;
3565 			if (time_after(jiffies,
3566 				       ata_deadline(last_jiffies, duration)))
3567 				return 0;
3568 			continue;
3569 		}
3570 
3571 		/* unstable, start over */
3572 		last = cur;
3573 		last_jiffies = jiffies;
3574 
3575 		/* Check deadline.  If debouncing failed, return
3576 		 * -EPIPE to tell upper layer to lower link speed.
3577 		 */
3578 		if (time_after(jiffies, deadline))
3579 			return -EPIPE;
3580 	}
3581 }
3582 
3583 /**
3584  *	sata_link_resume - resume SATA link
3585  *	@link: ATA link to resume SATA
3586  *	@params: timing parameters { interval, duratinon, timeout } in msec
3587  *	@deadline: deadline jiffies for the operation
3588  *
3589  *	Resume SATA phy @link and debounce it.
3590  *
3591  *	LOCKING:
3592  *	Kernel thread context (may sleep)
3593  *
3594  *	RETURNS:
3595  *	0 on success, -errno on failure.
3596  */
3597 int sata_link_resume(struct ata_link *link, const unsigned long *params,
3598 		     unsigned long deadline)
3599 {
3600 	u32 scontrol, serror;
3601 	int rc;
3602 
3603 	if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3604 		return rc;
3605 
3606 	scontrol = (scontrol & 0x0f0) | 0x300;
3607 
3608 	if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
3609 		return rc;
3610 
3611 	/* Some PHYs react badly if SStatus is pounded immediately
3612 	 * after resuming.  Delay 200ms before debouncing.
3613 	 */
3614 	msleep(200);
3615 
3616 	if ((rc = sata_link_debounce(link, params, deadline)))
3617 		return rc;
3618 
3619 	/* clear SError, some PHYs require this even for SRST to work */
3620 	if (!(rc = sata_scr_read(link, SCR_ERROR, &serror)))
3621 		rc = sata_scr_write(link, SCR_ERROR, serror);
3622 
3623 	return rc != -EINVAL ? rc : 0;
3624 }
3625 
3626 /**
3627  *	ata_std_prereset - prepare for reset
3628  *	@link: ATA link to be reset
3629  *	@deadline: deadline jiffies for the operation
3630  *
3631  *	@link is about to be reset.  Initialize it.  Failure from
3632  *	prereset makes libata abort whole reset sequence and give up
3633  *	that port, so prereset should be best-effort.  It does its
3634  *	best to prepare for reset sequence but if things go wrong, it
3635  *	should just whine, not fail.
3636  *
3637  *	LOCKING:
3638  *	Kernel thread context (may sleep)
3639  *
3640  *	RETURNS:
3641  *	0 on success, -errno otherwise.
3642  */
3643 int ata_std_prereset(struct ata_link *link, unsigned long deadline)
3644 {
3645 	struct ata_port *ap = link->ap;
3646 	struct ata_eh_context *ehc = &link->eh_context;
3647 	const unsigned long *timing = sata_ehc_deb_timing(ehc);
3648 	int rc;
3649 
3650 	/* if we're about to do hardreset, nothing more to do */
3651 	if (ehc->i.action & ATA_EH_HARDRESET)
3652 		return 0;
3653 
3654 	/* if SATA, resume link */
3655 	if (ap->flags & ATA_FLAG_SATA) {
3656 		rc = sata_link_resume(link, timing, deadline);
3657 		/* whine about phy resume failure but proceed */
3658 		if (rc && rc != -EOPNOTSUPP)
3659 			ata_link_printk(link, KERN_WARNING, "failed to resume "
3660 					"link for reset (errno=%d)\n", rc);
3661 	}
3662 
3663 	/* no point in trying softreset on offline link */
3664 	if (ata_phys_link_offline(link))
3665 		ehc->i.action &= ~ATA_EH_SOFTRESET;
3666 
3667 	return 0;
3668 }
3669 
3670 /**
3671  *	sata_link_hardreset - reset link via SATA phy reset
3672  *	@link: link to reset
3673  *	@timing: timing parameters { interval, duratinon, timeout } in msec
3674  *	@deadline: deadline jiffies for the operation
3675  *	@online: optional out parameter indicating link onlineness
3676  *	@check_ready: optional callback to check link readiness
3677  *
3678  *	SATA phy-reset @link using DET bits of SControl register.
3679  *	After hardreset, link readiness is waited upon using
3680  *	ata_wait_ready() if @check_ready is specified.  LLDs are
3681  *	allowed to not specify @check_ready and wait itself after this
3682  *	function returns.  Device classification is LLD's
3683  *	responsibility.
3684  *
3685  *	*@online is set to one iff reset succeeded and @link is online
3686  *	after reset.
3687  *
3688  *	LOCKING:
3689  *	Kernel thread context (may sleep)
3690  *
3691  *	RETURNS:
3692  *	0 on success, -errno otherwise.
3693  */
3694 int sata_link_hardreset(struct ata_link *link, const unsigned long *timing,
3695 			unsigned long deadline,
3696 			bool *online, int (*check_ready)(struct ata_link *))
3697 {
3698 	u32 scontrol;
3699 	int rc;
3700 
3701 	DPRINTK("ENTER\n");
3702 
3703 	if (online)
3704 		*online = false;
3705 
3706 	if (sata_set_spd_needed(link)) {
3707 		/* SATA spec says nothing about how to reconfigure
3708 		 * spd.  To be on the safe side, turn off phy during
3709 		 * reconfiguration.  This works for at least ICH7 AHCI
3710 		 * and Sil3124.
3711 		 */
3712 		if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3713 			goto out;
3714 
3715 		scontrol = (scontrol & 0x0f0) | 0x304;
3716 
3717 		if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
3718 			goto out;
3719 
3720 		sata_set_spd(link);
3721 	}
3722 
3723 	/* issue phy wake/reset */
3724 	if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3725 		goto out;
3726 
3727 	scontrol = (scontrol & 0x0f0) | 0x301;
3728 
3729 	if ((rc = sata_scr_write_flush(link, SCR_CONTROL, scontrol)))
3730 		goto out;
3731 
3732 	/* Couldn't find anything in SATA I/II specs, but AHCI-1.1
3733 	 * 10.4.2 says at least 1 ms.
3734 	 */
3735 	msleep(1);
3736 
3737 	/* bring link back */
3738 	rc = sata_link_resume(link, timing, deadline);
3739 	if (rc)
3740 		goto out;
3741 	/* if link is offline nothing more to do */
3742 	if (ata_phys_link_offline(link))
3743 		goto out;
3744 
3745 	/* Link is online.  From this point, -ENODEV too is an error. */
3746 	if (online)
3747 		*online = true;
3748 
3749 	if (sata_pmp_supported(link->ap) && ata_is_host_link(link)) {
3750 		/* If PMP is supported, we have to do follow-up SRST.
3751 		 * Some PMPs don't send D2H Reg FIS after hardreset if
3752 		 * the first port is empty.  Wait only for
3753 		 * ATA_TMOUT_PMP_SRST_WAIT.
3754 		 */
3755 		if (check_ready) {
3756 			unsigned long pmp_deadline;
3757 
3758 			pmp_deadline = ata_deadline(jiffies,
3759 						    ATA_TMOUT_PMP_SRST_WAIT);
3760 			if (time_after(pmp_deadline, deadline))
3761 				pmp_deadline = deadline;
3762 			ata_wait_ready(link, pmp_deadline, check_ready);
3763 		}
3764 		rc = -EAGAIN;
3765 		goto out;
3766 	}
3767 
3768 	rc = 0;
3769 	if (check_ready)
3770 		rc = ata_wait_ready(link, deadline, check_ready);
3771  out:
3772 	if (rc && rc != -EAGAIN) {
3773 		/* online is set iff link is online && reset succeeded */
3774 		if (online)
3775 			*online = false;
3776 		ata_link_printk(link, KERN_ERR,
3777 				"COMRESET failed (errno=%d)\n", rc);
3778 	}
3779 	DPRINTK("EXIT, rc=%d\n", rc);
3780 	return rc;
3781 }
3782 
3783 /**
3784  *	sata_std_hardreset - COMRESET w/o waiting or classification
3785  *	@link: link to reset
3786  *	@class: resulting class of attached device
3787  *	@deadline: deadline jiffies for the operation
3788  *
3789  *	Standard SATA COMRESET w/o waiting or classification.
3790  *
3791  *	LOCKING:
3792  *	Kernel thread context (may sleep)
3793  *
3794  *	RETURNS:
3795  *	0 if link offline, -EAGAIN if link online, -errno on errors.
3796  */
3797 int sata_std_hardreset(struct ata_link *link, unsigned int *class,
3798 		       unsigned long deadline)
3799 {
3800 	const unsigned long *timing = sata_ehc_deb_timing(&link->eh_context);
3801 	bool online;
3802 	int rc;
3803 
3804 	/* do hardreset */
3805 	rc = sata_link_hardreset(link, timing, deadline, &online, NULL);
3806 	return online ? -EAGAIN : rc;
3807 }
3808 
3809 /**
3810  *	ata_std_postreset - standard postreset callback
3811  *	@link: the target ata_link
3812  *	@classes: classes of attached devices
3813  *
3814  *	This function is invoked after a successful reset.  Note that
3815  *	the device might have been reset more than once using
3816  *	different reset methods before postreset is invoked.
3817  *
3818  *	LOCKING:
3819  *	Kernel thread context (may sleep)
3820  */
3821 void ata_std_postreset(struct ata_link *link, unsigned int *classes)
3822 {
3823 	u32 serror;
3824 
3825 	DPRINTK("ENTER\n");
3826 
3827 	/* reset complete, clear SError */
3828 	if (!sata_scr_read(link, SCR_ERROR, &serror))
3829 		sata_scr_write(link, SCR_ERROR, serror);
3830 
3831 	/* print link status */
3832 	sata_print_link_status(link);
3833 
3834 	DPRINTK("EXIT\n");
3835 }
3836 
3837 /**
3838  *	ata_dev_same_device - Determine whether new ID matches configured device
3839  *	@dev: device to compare against
3840  *	@new_class: class of the new device
3841  *	@new_id: IDENTIFY page of the new device
3842  *
3843  *	Compare @new_class and @new_id against @dev and determine
3844  *	whether @dev is the device indicated by @new_class and
3845  *	@new_id.
3846  *
3847  *	LOCKING:
3848  *	None.
3849  *
3850  *	RETURNS:
3851  *	1 if @dev matches @new_class and @new_id, 0 otherwise.
3852  */
3853 static int ata_dev_same_device(struct ata_device *dev, unsigned int new_class,
3854 			       const u16 *new_id)
3855 {
3856 	const u16 *old_id = dev->id;
3857 	unsigned char model[2][ATA_ID_PROD_LEN + 1];
3858 	unsigned char serial[2][ATA_ID_SERNO_LEN + 1];
3859 
3860 	if (dev->class != new_class) {
3861 		ata_dev_printk(dev, KERN_INFO, "class mismatch %d != %d\n",
3862 			       dev->class, new_class);
3863 		return 0;
3864 	}
3865 
3866 	ata_id_c_string(old_id, model[0], ATA_ID_PROD, sizeof(model[0]));
3867 	ata_id_c_string(new_id, model[1], ATA_ID_PROD, sizeof(model[1]));
3868 	ata_id_c_string(old_id, serial[0], ATA_ID_SERNO, sizeof(serial[0]));
3869 	ata_id_c_string(new_id, serial[1], ATA_ID_SERNO, sizeof(serial[1]));
3870 
3871 	if (strcmp(model[0], model[1])) {
3872 		ata_dev_printk(dev, KERN_INFO, "model number mismatch "
3873 			       "'%s' != '%s'\n", model[0], model[1]);
3874 		return 0;
3875 	}
3876 
3877 	if (strcmp(serial[0], serial[1])) {
3878 		ata_dev_printk(dev, KERN_INFO, "serial number mismatch "
3879 			       "'%s' != '%s'\n", serial[0], serial[1]);
3880 		return 0;
3881 	}
3882 
3883 	return 1;
3884 }
3885 
3886 /**
3887  *	ata_dev_reread_id - Re-read IDENTIFY data
3888  *	@dev: target ATA device
3889  *	@readid_flags: read ID flags
3890  *
3891  *	Re-read IDENTIFY page and make sure @dev is still attached to
3892  *	the port.
3893  *
3894  *	LOCKING:
3895  *	Kernel thread context (may sleep)
3896  *
3897  *	RETURNS:
3898  *	0 on success, negative errno otherwise
3899  */
3900 int ata_dev_reread_id(struct ata_device *dev, unsigned int readid_flags)
3901 {
3902 	unsigned int class = dev->class;
3903 	u16 *id = (void *)dev->link->ap->sector_buf;
3904 	int rc;
3905 
3906 	/* read ID data */
3907 	rc = ata_dev_read_id(dev, &class, readid_flags, id);
3908 	if (rc)
3909 		return rc;
3910 
3911 	/* is the device still there? */
3912 	if (!ata_dev_same_device(dev, class, id))
3913 		return -ENODEV;
3914 
3915 	memcpy(dev->id, id, sizeof(id[0]) * ATA_ID_WORDS);
3916 	return 0;
3917 }
3918 
3919 /**
3920  *	ata_dev_revalidate - Revalidate ATA device
3921  *	@dev: device to revalidate
3922  *	@new_class: new class code
3923  *	@readid_flags: read ID flags
3924  *
3925  *	Re-read IDENTIFY page, make sure @dev is still attached to the
3926  *	port and reconfigure it according to the new IDENTIFY page.
3927  *
3928  *	LOCKING:
3929  *	Kernel thread context (may sleep)
3930  *
3931  *	RETURNS:
3932  *	0 on success, negative errno otherwise
3933  */
3934 int ata_dev_revalidate(struct ata_device *dev, unsigned int new_class,
3935 		       unsigned int readid_flags)
3936 {
3937 	u64 n_sectors = dev->n_sectors;
3938 	int rc;
3939 
3940 	if (!ata_dev_enabled(dev))
3941 		return -ENODEV;
3942 
3943 	/* fail early if !ATA && !ATAPI to avoid issuing [P]IDENTIFY to PMP */
3944 	if (ata_class_enabled(new_class) &&
3945 	    new_class != ATA_DEV_ATA && new_class != ATA_DEV_ATAPI) {
3946 		ata_dev_printk(dev, KERN_INFO, "class mismatch %u != %u\n",
3947 			       dev->class, new_class);
3948 		rc = -ENODEV;
3949 		goto fail;
3950 	}
3951 
3952 	/* re-read ID */
3953 	rc = ata_dev_reread_id(dev, readid_flags);
3954 	if (rc)
3955 		goto fail;
3956 
3957 	/* configure device according to the new ID */
3958 	rc = ata_dev_configure(dev);
3959 	if (rc)
3960 		goto fail;
3961 
3962 	/* verify n_sectors hasn't changed */
3963 	if (dev->class == ATA_DEV_ATA && n_sectors &&
3964 	    dev->n_sectors != n_sectors) {
3965 		ata_dev_printk(dev, KERN_INFO, "n_sectors mismatch "
3966 			       "%llu != %llu\n",
3967 			       (unsigned long long)n_sectors,
3968 			       (unsigned long long)dev->n_sectors);
3969 
3970 		/* restore original n_sectors */
3971 		dev->n_sectors = n_sectors;
3972 
3973 		rc = -ENODEV;
3974 		goto fail;
3975 	}
3976 
3977 	return 0;
3978 
3979  fail:
3980 	ata_dev_printk(dev, KERN_ERR, "revalidation failed (errno=%d)\n", rc);
3981 	return rc;
3982 }
3983 
3984 struct ata_blacklist_entry {
3985 	const char *model_num;
3986 	const char *model_rev;
3987 	unsigned long horkage;
3988 };
3989 
3990 static const struct ata_blacklist_entry ata_device_blacklist [] = {
3991 	/* Devices with DMA related problems under Linux */
3992 	{ "WDC AC11000H",	NULL,		ATA_HORKAGE_NODMA },
3993 	{ "WDC AC22100H",	NULL,		ATA_HORKAGE_NODMA },
3994 	{ "WDC AC32500H",	NULL,		ATA_HORKAGE_NODMA },
3995 	{ "WDC AC33100H",	NULL,		ATA_HORKAGE_NODMA },
3996 	{ "WDC AC31600H",	NULL,		ATA_HORKAGE_NODMA },
3997 	{ "WDC AC32100H",	"24.09P07",	ATA_HORKAGE_NODMA },
3998 	{ "WDC AC23200L",	"21.10N21",	ATA_HORKAGE_NODMA },
3999 	{ "Compaq CRD-8241B", 	NULL,		ATA_HORKAGE_NODMA },
4000 	{ "CRD-8400B",		NULL, 		ATA_HORKAGE_NODMA },
4001 	{ "CRD-8480B",		NULL,		ATA_HORKAGE_NODMA },
4002 	{ "CRD-8482B",		NULL,		ATA_HORKAGE_NODMA },
4003 	{ "CRD-84",		NULL,		ATA_HORKAGE_NODMA },
4004 	{ "SanDisk SDP3B",	NULL,		ATA_HORKAGE_NODMA },
4005 	{ "SanDisk SDP3B-64",	NULL,		ATA_HORKAGE_NODMA },
4006 	{ "SANYO CD-ROM CRD",	NULL,		ATA_HORKAGE_NODMA },
4007 	{ "HITACHI CDR-8",	NULL,		ATA_HORKAGE_NODMA },
4008 	{ "HITACHI CDR-8335",	NULL,		ATA_HORKAGE_NODMA },
4009 	{ "HITACHI CDR-8435",	NULL,		ATA_HORKAGE_NODMA },
4010 	{ "Toshiba CD-ROM XM-6202B", NULL,	ATA_HORKAGE_NODMA },
4011 	{ "TOSHIBA CD-ROM XM-1702BC", NULL,	ATA_HORKAGE_NODMA },
4012 	{ "CD-532E-A", 		NULL,		ATA_HORKAGE_NODMA },
4013 	{ "E-IDE CD-ROM CR-840",NULL,		ATA_HORKAGE_NODMA },
4014 	{ "CD-ROM Drive/F5A",	NULL,		ATA_HORKAGE_NODMA },
4015 	{ "WPI CDD-820", 	NULL,		ATA_HORKAGE_NODMA },
4016 	{ "SAMSUNG CD-ROM SC-148C", NULL,	ATA_HORKAGE_NODMA },
4017 	{ "SAMSUNG CD-ROM SC",	NULL,		ATA_HORKAGE_NODMA },
4018 	{ "ATAPI CD-ROM DRIVE 40X MAXIMUM",NULL,ATA_HORKAGE_NODMA },
4019 	{ "_NEC DV5800A", 	NULL,		ATA_HORKAGE_NODMA },
4020 	{ "SAMSUNG CD-ROM SN-124", "N001",	ATA_HORKAGE_NODMA },
4021 	{ "Seagate STT20000A", NULL,		ATA_HORKAGE_NODMA },
4022 	/* Odd clown on sil3726/4726 PMPs */
4023 	{ "Config  Disk",	NULL,		ATA_HORKAGE_DISABLE },
4024 
4025 	/* Weird ATAPI devices */
4026 	{ "TORiSAN DVD-ROM DRD-N216", NULL,	ATA_HORKAGE_MAX_SEC_128 },
4027 
4028 	/* Devices we expect to fail diagnostics */
4029 
4030 	/* Devices where NCQ should be avoided */
4031 	/* NCQ is slow */
4032 	{ "WDC WD740ADFD-00",	NULL,		ATA_HORKAGE_NONCQ },
4033 	{ "WDC WD740ADFD-00NLR1", NULL,		ATA_HORKAGE_NONCQ, },
4034 	/* http://thread.gmane.org/gmane.linux.ide/14907 */
4035 	{ "FUJITSU MHT2060BH",	NULL,		ATA_HORKAGE_NONCQ },
4036 	/* NCQ is broken */
4037 	{ "Maxtor *",		"BANC*",	ATA_HORKAGE_NONCQ },
4038 	{ "Maxtor 7V300F0",	"VA111630",	ATA_HORKAGE_NONCQ },
4039 	{ "ST380817AS",		"3.42",		ATA_HORKAGE_NONCQ },
4040 	{ "ST3160023AS",	"3.42",		ATA_HORKAGE_NONCQ },
4041 
4042 	/* Blacklist entries taken from Silicon Image 3124/3132
4043 	   Windows driver .inf file - also several Linux problem reports */
4044 	{ "HTS541060G9SA00",    "MB3OC60D",     ATA_HORKAGE_NONCQ, },
4045 	{ "HTS541080G9SA00",    "MB4OC60D",     ATA_HORKAGE_NONCQ, },
4046 	{ "HTS541010G9SA00",    "MBZOC60D",     ATA_HORKAGE_NONCQ, },
4047 
4048 	/* devices which puke on READ_NATIVE_MAX */
4049 	{ "HDS724040KLSA80",	"KFAOA20N",	ATA_HORKAGE_BROKEN_HPA, },
4050 	{ "WDC WD3200JD-00KLB0", "WD-WCAMR1130137", ATA_HORKAGE_BROKEN_HPA },
4051 	{ "WDC WD2500JD-00HBB0", "WD-WMAL71490727", ATA_HORKAGE_BROKEN_HPA },
4052 	{ "MAXTOR 6L080L4",	"A93.0500",	ATA_HORKAGE_BROKEN_HPA },
4053 
4054 	/* Devices which report 1 sector over size HPA */
4055 	{ "ST340823A",		NULL,		ATA_HORKAGE_HPA_SIZE, },
4056 	{ "ST320413A",		NULL,		ATA_HORKAGE_HPA_SIZE, },
4057 	{ "ST310211A",		NULL,		ATA_HORKAGE_HPA_SIZE, },
4058 
4059 	/* Devices which get the IVB wrong */
4060 	{ "QUANTUM FIREBALLlct10 05", "A03.0900", ATA_HORKAGE_IVB, },
4061 	/* Maybe we should just blacklist TSSTcorp... */
4062 	{ "TSSTcorp CDDVDW SH-S202H", "SB00",	  ATA_HORKAGE_IVB, },
4063 	{ "TSSTcorp CDDVDW SH-S202H", "SB01",	  ATA_HORKAGE_IVB, },
4064 	{ "TSSTcorp CDDVDW SH-S202J", "SB00",	  ATA_HORKAGE_IVB, },
4065 	{ "TSSTcorp CDDVDW SH-S202J", "SB01",	  ATA_HORKAGE_IVB, },
4066 	{ "TSSTcorp CDDVDW SH-S202N", "SB00",	  ATA_HORKAGE_IVB, },
4067 	{ "TSSTcorp CDDVDW SH-S202N", "SB01",	  ATA_HORKAGE_IVB, },
4068 
4069 	/* Devices that do not need bridging limits applied */
4070 	{ "MTRON MSP-SATA*",		NULL,	ATA_HORKAGE_BRIDGE_OK, },
4071 
4072 	/* End Marker */
4073 	{ }
4074 };
4075 
4076 static int strn_pattern_cmp(const char *patt, const char *name, int wildchar)
4077 {
4078 	const char *p;
4079 	int len;
4080 
4081 	/*
4082 	 * check for trailing wildcard: *\0
4083 	 */
4084 	p = strchr(patt, wildchar);
4085 	if (p && ((*(p + 1)) == 0))
4086 		len = p - patt;
4087 	else {
4088 		len = strlen(name);
4089 		if (!len) {
4090 			if (!*patt)
4091 				return 0;
4092 			return -1;
4093 		}
4094 	}
4095 
4096 	return strncmp(patt, name, len);
4097 }
4098 
4099 static unsigned long ata_dev_blacklisted(const struct ata_device *dev)
4100 {
4101 	unsigned char model_num[ATA_ID_PROD_LEN + 1];
4102 	unsigned char model_rev[ATA_ID_FW_REV_LEN + 1];
4103 	const struct ata_blacklist_entry *ad = ata_device_blacklist;
4104 
4105 	ata_id_c_string(dev->id, model_num, ATA_ID_PROD, sizeof(model_num));
4106 	ata_id_c_string(dev->id, model_rev, ATA_ID_FW_REV, sizeof(model_rev));
4107 
4108 	while (ad->model_num) {
4109 		if (!strn_pattern_cmp(ad->model_num, model_num, '*')) {
4110 			if (ad->model_rev == NULL)
4111 				return ad->horkage;
4112 			if (!strn_pattern_cmp(ad->model_rev, model_rev, '*'))
4113 				return ad->horkage;
4114 		}
4115 		ad++;
4116 	}
4117 	return 0;
4118 }
4119 
4120 static int ata_dma_blacklisted(const struct ata_device *dev)
4121 {
4122 	/* We don't support polling DMA.
4123 	 * DMA blacklist those ATAPI devices with CDB-intr (and use PIO)
4124 	 * if the LLDD handles only interrupts in the HSM_ST_LAST state.
4125 	 */
4126 	if ((dev->link->ap->flags & ATA_FLAG_PIO_POLLING) &&
4127 	    (dev->flags & ATA_DFLAG_CDB_INTR))
4128 		return 1;
4129 	return (dev->horkage & ATA_HORKAGE_NODMA) ? 1 : 0;
4130 }
4131 
4132 /**
4133  *	ata_is_40wire		-	check drive side detection
4134  *	@dev: device
4135  *
4136  *	Perform drive side detection decoding, allowing for device vendors
4137  *	who can't follow the documentation.
4138  */
4139 
4140 static int ata_is_40wire(struct ata_device *dev)
4141 {
4142 	if (dev->horkage & ATA_HORKAGE_IVB)
4143 		return ata_drive_40wire_relaxed(dev->id);
4144 	return ata_drive_40wire(dev->id);
4145 }
4146 
4147 /**
4148  *	cable_is_40wire		-	40/80/SATA decider
4149  *	@ap: port to consider
4150  *
4151  *	This function encapsulates the policy for speed management
4152  *	in one place. At the moment we don't cache the result but
4153  *	there is a good case for setting ap->cbl to the result when
4154  *	we are called with unknown cables (and figuring out if it
4155  *	impacts hotplug at all).
4156  *
4157  *	Return 1 if the cable appears to be 40 wire.
4158  */
4159 
4160 static int cable_is_40wire(struct ata_port *ap)
4161 {
4162 	struct ata_link *link;
4163 	struct ata_device *dev;
4164 
4165 	/* If the controller thinks we are 40 wire, we are. */
4166 	if (ap->cbl == ATA_CBL_PATA40)
4167 		return 1;
4168 
4169 	/* If the controller thinks we are 80 wire, we are. */
4170 	if (ap->cbl == ATA_CBL_PATA80 || ap->cbl == ATA_CBL_SATA)
4171 		return 0;
4172 
4173 	/* If the system is known to be 40 wire short cable (eg
4174 	 * laptop), then we allow 80 wire modes even if the drive
4175 	 * isn't sure.
4176 	 */
4177 	if (ap->cbl == ATA_CBL_PATA40_SHORT)
4178 		return 0;
4179 
4180 	/* If the controller doesn't know, we scan.
4181 	 *
4182 	 * Note: We look for all 40 wire detects at this point.  Any
4183 	 *       80 wire detect is taken to be 80 wire cable because
4184 	 * - in many setups only the one drive (slave if present) will
4185 	 *   give a valid detect
4186 	 * - if you have a non detect capable drive you don't want it
4187 	 *   to colour the choice
4188 	 */
4189 	ata_port_for_each_link(link, ap) {
4190 		ata_link_for_each_dev(dev, link) {
4191 			if (ata_dev_enabled(dev) && !ata_is_40wire(dev))
4192 				return 0;
4193 		}
4194 	}
4195 	return 1;
4196 }
4197 
4198 /**
4199  *	ata_dev_xfermask - Compute supported xfermask of the given device
4200  *	@dev: Device to compute xfermask for
4201  *
4202  *	Compute supported xfermask of @dev and store it in
4203  *	dev->*_mask.  This function is responsible for applying all
4204  *	known limits including host controller limits, device
4205  *	blacklist, etc...
4206  *
4207  *	LOCKING:
4208  *	None.
4209  */
4210 static void ata_dev_xfermask(struct ata_device *dev)
4211 {
4212 	struct ata_link *link = dev->link;
4213 	struct ata_port *ap = link->ap;
4214 	struct ata_host *host = ap->host;
4215 	unsigned long xfer_mask;
4216 
4217 	/* controller modes available */
4218 	xfer_mask = ata_pack_xfermask(ap->pio_mask,
4219 				      ap->mwdma_mask, ap->udma_mask);
4220 
4221 	/* drive modes available */
4222 	xfer_mask &= ata_pack_xfermask(dev->pio_mask,
4223 				       dev->mwdma_mask, dev->udma_mask);
4224 	xfer_mask &= ata_id_xfermask(dev->id);
4225 
4226 	/*
4227 	 *	CFA Advanced TrueIDE timings are not allowed on a shared
4228 	 *	cable
4229 	 */
4230 	if (ata_dev_pair(dev)) {
4231 		/* No PIO5 or PIO6 */
4232 		xfer_mask &= ~(0x03 << (ATA_SHIFT_PIO + 5));
4233 		/* No MWDMA3 or MWDMA 4 */
4234 		xfer_mask &= ~(0x03 << (ATA_SHIFT_MWDMA + 3));
4235 	}
4236 
4237 	if (ata_dma_blacklisted(dev)) {
4238 		xfer_mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA);
4239 		ata_dev_printk(dev, KERN_WARNING,
4240 			       "device is on DMA blacklist, disabling DMA\n");
4241 	}
4242 
4243 	if ((host->flags & ATA_HOST_SIMPLEX) &&
4244 	    host->simplex_claimed && host->simplex_claimed != ap) {
4245 		xfer_mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA);
4246 		ata_dev_printk(dev, KERN_WARNING, "simplex DMA is claimed by "
4247 			       "other device, disabling DMA\n");
4248 	}
4249 
4250 	if (ap->flags & ATA_FLAG_NO_IORDY)
4251 		xfer_mask &= ata_pio_mask_no_iordy(dev);
4252 
4253 	if (ap->ops->mode_filter)
4254 		xfer_mask = ap->ops->mode_filter(dev, xfer_mask);
4255 
4256 	/* Apply cable rule here.  Don't apply it early because when
4257 	 * we handle hot plug the cable type can itself change.
4258 	 * Check this last so that we know if the transfer rate was
4259 	 * solely limited by the cable.
4260 	 * Unknown or 80 wire cables reported host side are checked
4261 	 * drive side as well. Cases where we know a 40wire cable
4262 	 * is used safely for 80 are not checked here.
4263 	 */
4264 	if (xfer_mask & (0xF8 << ATA_SHIFT_UDMA))
4265 		/* UDMA/44 or higher would be available */
4266 		if (cable_is_40wire(ap)) {
4267 			ata_dev_printk(dev, KERN_WARNING,
4268 				 "limited to UDMA/33 due to 40-wire cable\n");
4269 			xfer_mask &= ~(0xF8 << ATA_SHIFT_UDMA);
4270 		}
4271 
4272 	ata_unpack_xfermask(xfer_mask, &dev->pio_mask,
4273 			    &dev->mwdma_mask, &dev->udma_mask);
4274 }
4275 
4276 /**
4277  *	ata_dev_set_xfermode - Issue SET FEATURES - XFER MODE command
4278  *	@dev: Device to which command will be sent
4279  *
4280  *	Issue SET FEATURES - XFER MODE command to device @dev
4281  *	on port @ap.
4282  *
4283  *	LOCKING:
4284  *	PCI/etc. bus probe sem.
4285  *
4286  *	RETURNS:
4287  *	0 on success, AC_ERR_* mask otherwise.
4288  */
4289 
4290 static unsigned int ata_dev_set_xfermode(struct ata_device *dev)
4291 {
4292 	struct ata_taskfile tf;
4293 	unsigned int err_mask;
4294 
4295 	/* set up set-features taskfile */
4296 	DPRINTK("set features - xfer mode\n");
4297 
4298 	/* Some controllers and ATAPI devices show flaky interrupt
4299 	 * behavior after setting xfer mode.  Use polling instead.
4300 	 */
4301 	ata_tf_init(dev, &tf);
4302 	tf.command = ATA_CMD_SET_FEATURES;
4303 	tf.feature = SETFEATURES_XFER;
4304 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE | ATA_TFLAG_POLLING;
4305 	tf.protocol = ATA_PROT_NODATA;
4306 	/* If we are using IORDY we must send the mode setting command */
4307 	if (ata_pio_need_iordy(dev))
4308 		tf.nsect = dev->xfer_mode;
4309 	/* If the device has IORDY and the controller does not - turn it off */
4310  	else if (ata_id_has_iordy(dev->id))
4311 		tf.nsect = 0x01;
4312 	else /* In the ancient relic department - skip all of this */
4313 		return 0;
4314 
4315 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
4316 
4317 	DPRINTK("EXIT, err_mask=%x\n", err_mask);
4318 	return err_mask;
4319 }
4320 /**
4321  *	ata_dev_set_feature - Issue SET FEATURES - SATA FEATURES
4322  *	@dev: Device to which command will be sent
4323  *	@enable: Whether to enable or disable the feature
4324  *	@feature: The sector count represents the feature to set
4325  *
4326  *	Issue SET FEATURES - SATA FEATURES command to device @dev
4327  *	on port @ap with sector count
4328  *
4329  *	LOCKING:
4330  *	PCI/etc. bus probe sem.
4331  *
4332  *	RETURNS:
4333  *	0 on success, AC_ERR_* mask otherwise.
4334  */
4335 static unsigned int ata_dev_set_feature(struct ata_device *dev, u8 enable,
4336 					u8 feature)
4337 {
4338 	struct ata_taskfile tf;
4339 	unsigned int err_mask;
4340 
4341 	/* set up set-features taskfile */
4342 	DPRINTK("set features - SATA features\n");
4343 
4344 	ata_tf_init(dev, &tf);
4345 	tf.command = ATA_CMD_SET_FEATURES;
4346 	tf.feature = enable;
4347 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
4348 	tf.protocol = ATA_PROT_NODATA;
4349 	tf.nsect = feature;
4350 
4351 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
4352 
4353 	DPRINTK("EXIT, err_mask=%x\n", err_mask);
4354 	return err_mask;
4355 }
4356 
4357 /**
4358  *	ata_dev_init_params - Issue INIT DEV PARAMS command
4359  *	@dev: Device to which command will be sent
4360  *	@heads: Number of heads (taskfile parameter)
4361  *	@sectors: Number of sectors (taskfile parameter)
4362  *
4363  *	LOCKING:
4364  *	Kernel thread context (may sleep)
4365  *
4366  *	RETURNS:
4367  *	0 on success, AC_ERR_* mask otherwise.
4368  */
4369 static unsigned int ata_dev_init_params(struct ata_device *dev,
4370 					u16 heads, u16 sectors)
4371 {
4372 	struct ata_taskfile tf;
4373 	unsigned int err_mask;
4374 
4375 	/* Number of sectors per track 1-255. Number of heads 1-16 */
4376 	if (sectors < 1 || sectors > 255 || heads < 1 || heads > 16)
4377 		return AC_ERR_INVALID;
4378 
4379 	/* set up init dev params taskfile */
4380 	DPRINTK("init dev params \n");
4381 
4382 	ata_tf_init(dev, &tf);
4383 	tf.command = ATA_CMD_INIT_DEV_PARAMS;
4384 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
4385 	tf.protocol = ATA_PROT_NODATA;
4386 	tf.nsect = sectors;
4387 	tf.device |= (heads - 1) & 0x0f; /* max head = num. of heads - 1 */
4388 
4389 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
4390 	/* A clean abort indicates an original or just out of spec drive
4391 	   and we should continue as we issue the setup based on the
4392 	   drive reported working geometry */
4393 	if (err_mask == AC_ERR_DEV && (tf.feature & ATA_ABORTED))
4394 		err_mask = 0;
4395 
4396 	DPRINTK("EXIT, err_mask=%x\n", err_mask);
4397 	return err_mask;
4398 }
4399 
4400 /**
4401  *	ata_sg_clean - Unmap DMA memory associated with command
4402  *	@qc: Command containing DMA memory to be released
4403  *
4404  *	Unmap all mapped DMA memory associated with this command.
4405  *
4406  *	LOCKING:
4407  *	spin_lock_irqsave(host lock)
4408  */
4409 void ata_sg_clean(struct ata_queued_cmd *qc)
4410 {
4411 	struct ata_port *ap = qc->ap;
4412 	struct scatterlist *sg = qc->sg;
4413 	int dir = qc->dma_dir;
4414 
4415 	WARN_ON(sg == NULL);
4416 
4417 	VPRINTK("unmapping %u sg elements\n", qc->n_elem);
4418 
4419 	if (qc->n_elem)
4420 		dma_unmap_sg(ap->dev, sg, qc->n_elem, dir);
4421 
4422 	qc->flags &= ~ATA_QCFLAG_DMAMAP;
4423 	qc->sg = NULL;
4424 }
4425 
4426 /**
4427  *	atapi_check_dma - Check whether ATAPI DMA can be supported
4428  *	@qc: Metadata associated with taskfile to check
4429  *
4430  *	Allow low-level driver to filter ATA PACKET commands, returning
4431  *	a status indicating whether or not it is OK to use DMA for the
4432  *	supplied PACKET command.
4433  *
4434  *	LOCKING:
4435  *	spin_lock_irqsave(host lock)
4436  *
4437  *	RETURNS: 0 when ATAPI DMA can be used
4438  *               nonzero otherwise
4439  */
4440 int atapi_check_dma(struct ata_queued_cmd *qc)
4441 {
4442 	struct ata_port *ap = qc->ap;
4443 
4444 	/* Don't allow DMA if it isn't multiple of 16 bytes.  Quite a
4445 	 * few ATAPI devices choke on such DMA requests.
4446 	 */
4447 	if (unlikely(qc->nbytes & 15))
4448 		return 1;
4449 
4450 	if (ap->ops->check_atapi_dma)
4451 		return ap->ops->check_atapi_dma(qc);
4452 
4453 	return 0;
4454 }
4455 
4456 /**
4457  *	ata_std_qc_defer - Check whether a qc needs to be deferred
4458  *	@qc: ATA command in question
4459  *
4460  *	Non-NCQ commands cannot run with any other command, NCQ or
4461  *	not.  As upper layer only knows the queue depth, we are
4462  *	responsible for maintaining exclusion.  This function checks
4463  *	whether a new command @qc can be issued.
4464  *
4465  *	LOCKING:
4466  *	spin_lock_irqsave(host lock)
4467  *
4468  *	RETURNS:
4469  *	ATA_DEFER_* if deferring is needed, 0 otherwise.
4470  */
4471 int ata_std_qc_defer(struct ata_queued_cmd *qc)
4472 {
4473 	struct ata_link *link = qc->dev->link;
4474 
4475 	if (qc->tf.protocol == ATA_PROT_NCQ) {
4476 		if (!ata_tag_valid(link->active_tag))
4477 			return 0;
4478 	} else {
4479 		if (!ata_tag_valid(link->active_tag) && !link->sactive)
4480 			return 0;
4481 	}
4482 
4483 	return ATA_DEFER_LINK;
4484 }
4485 
4486 void ata_noop_qc_prep(struct ata_queued_cmd *qc) { }
4487 
4488 /**
4489  *	ata_sg_init - Associate command with scatter-gather table.
4490  *	@qc: Command to be associated
4491  *	@sg: Scatter-gather table.
4492  *	@n_elem: Number of elements in s/g table.
4493  *
4494  *	Initialize the data-related elements of queued_cmd @qc
4495  *	to point to a scatter-gather table @sg, containing @n_elem
4496  *	elements.
4497  *
4498  *	LOCKING:
4499  *	spin_lock_irqsave(host lock)
4500  */
4501 void ata_sg_init(struct ata_queued_cmd *qc, struct scatterlist *sg,
4502 		 unsigned int n_elem)
4503 {
4504 	qc->sg = sg;
4505 	qc->n_elem = n_elem;
4506 	qc->cursg = qc->sg;
4507 }
4508 
4509 /**
4510  *	ata_sg_setup - DMA-map the scatter-gather table associated with a command.
4511  *	@qc: Command with scatter-gather table to be mapped.
4512  *
4513  *	DMA-map the scatter-gather table associated with queued_cmd @qc.
4514  *
4515  *	LOCKING:
4516  *	spin_lock_irqsave(host lock)
4517  *
4518  *	RETURNS:
4519  *	Zero on success, negative on error.
4520  *
4521  */
4522 static int ata_sg_setup(struct ata_queued_cmd *qc)
4523 {
4524 	struct ata_port *ap = qc->ap;
4525 	unsigned int n_elem;
4526 
4527 	VPRINTK("ENTER, ata%u\n", ap->print_id);
4528 
4529 	n_elem = dma_map_sg(ap->dev, qc->sg, qc->n_elem, qc->dma_dir);
4530 	if (n_elem < 1)
4531 		return -1;
4532 
4533 	DPRINTK("%d sg elements mapped\n", n_elem);
4534 
4535 	qc->n_elem = n_elem;
4536 	qc->flags |= ATA_QCFLAG_DMAMAP;
4537 
4538 	return 0;
4539 }
4540 
4541 /**
4542  *	swap_buf_le16 - swap halves of 16-bit words in place
4543  *	@buf:  Buffer to swap
4544  *	@buf_words:  Number of 16-bit words in buffer.
4545  *
4546  *	Swap halves of 16-bit words if needed to convert from
4547  *	little-endian byte order to native cpu byte order, or
4548  *	vice-versa.
4549  *
4550  *	LOCKING:
4551  *	Inherited from caller.
4552  */
4553 void swap_buf_le16(u16 *buf, unsigned int buf_words)
4554 {
4555 #ifdef __BIG_ENDIAN
4556 	unsigned int i;
4557 
4558 	for (i = 0; i < buf_words; i++)
4559 		buf[i] = le16_to_cpu(buf[i]);
4560 #endif /* __BIG_ENDIAN */
4561 }
4562 
4563 /**
4564  *	ata_qc_new_init - Request an available ATA command, and initialize it
4565  *	@dev: Device from whom we request an available command structure
4566  *	@tag: command tag
4567  *
4568  *	LOCKING:
4569  *	None.
4570  */
4571 
4572 struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev, int tag)
4573 {
4574 	struct ata_port *ap = dev->link->ap;
4575 	struct ata_queued_cmd *qc;
4576 
4577 	if (unlikely(ap->pflags & ATA_PFLAG_FROZEN))
4578 		return NULL;
4579 
4580 	qc = __ata_qc_from_tag(ap, tag);
4581 	if (qc) {
4582 		qc->scsicmd = NULL;
4583 		qc->ap = ap;
4584 		qc->dev = dev;
4585 		qc->tag = tag;
4586 
4587 		ata_qc_reinit(qc);
4588 	}
4589 
4590 	return qc;
4591 }
4592 
4593 void __ata_qc_complete(struct ata_queued_cmd *qc)
4594 {
4595 	struct ata_port *ap = qc->ap;
4596 	struct ata_link *link = qc->dev->link;
4597 
4598 	WARN_ON(qc == NULL);	/* ata_qc_from_tag _might_ return NULL */
4599 	WARN_ON(!(qc->flags & ATA_QCFLAG_ACTIVE));
4600 
4601 	if (likely(qc->flags & ATA_QCFLAG_DMAMAP))
4602 		ata_sg_clean(qc);
4603 
4604 	/* command should be marked inactive atomically with qc completion */
4605 	if (qc->tf.protocol == ATA_PROT_NCQ) {
4606 		link->sactive &= ~(1 << qc->tag);
4607 		if (!link->sactive)
4608 			ap->nr_active_links--;
4609 	} else {
4610 		link->active_tag = ATA_TAG_POISON;
4611 		ap->nr_active_links--;
4612 	}
4613 
4614 	/* clear exclusive status */
4615 	if (unlikely(qc->flags & ATA_QCFLAG_CLEAR_EXCL &&
4616 		     ap->excl_link == link))
4617 		ap->excl_link = NULL;
4618 
4619 	/* atapi: mark qc as inactive to prevent the interrupt handler
4620 	 * from completing the command twice later, before the error handler
4621 	 * is called. (when rc != 0 and atapi request sense is needed)
4622 	 */
4623 	qc->flags &= ~ATA_QCFLAG_ACTIVE;
4624 	ap->qc_active &= ~(1 << qc->tag);
4625 
4626 	/* call completion callback */
4627 	qc->complete_fn(qc);
4628 }
4629 
4630 static void fill_result_tf(struct ata_queued_cmd *qc)
4631 {
4632 	struct ata_port *ap = qc->ap;
4633 
4634 	qc->result_tf.flags = qc->tf.flags;
4635 	ap->ops->qc_fill_rtf(qc);
4636 }
4637 
4638 static void ata_verify_xfer(struct ata_queued_cmd *qc)
4639 {
4640 	struct ata_device *dev = qc->dev;
4641 
4642 	if (ata_tag_internal(qc->tag))
4643 		return;
4644 
4645 	if (ata_is_nodata(qc->tf.protocol))
4646 		return;
4647 
4648 	if ((dev->mwdma_mask || dev->udma_mask) && ata_is_pio(qc->tf.protocol))
4649 		return;
4650 
4651 	dev->flags &= ~ATA_DFLAG_DUBIOUS_XFER;
4652 }
4653 
4654 /**
4655  *	ata_qc_complete - Complete an active ATA command
4656  *	@qc: Command to complete
4657  *
4658  *	Indicate to the mid and upper layers that an ATA
4659  *	command has completed, with either an ok or not-ok status.
4660  *
4661  *	LOCKING:
4662  *	spin_lock_irqsave(host lock)
4663  */
4664 void ata_qc_complete(struct ata_queued_cmd *qc)
4665 {
4666 	struct ata_port *ap = qc->ap;
4667 
4668 	/* XXX: New EH and old EH use different mechanisms to
4669 	 * synchronize EH with regular execution path.
4670 	 *
4671 	 * In new EH, a failed qc is marked with ATA_QCFLAG_FAILED.
4672 	 * Normal execution path is responsible for not accessing a
4673 	 * failed qc.  libata core enforces the rule by returning NULL
4674 	 * from ata_qc_from_tag() for failed qcs.
4675 	 *
4676 	 * Old EH depends on ata_qc_complete() nullifying completion
4677 	 * requests if ATA_QCFLAG_EH_SCHEDULED is set.  Old EH does
4678 	 * not synchronize with interrupt handler.  Only PIO task is
4679 	 * taken care of.
4680 	 */
4681 	if (ap->ops->error_handler) {
4682 		struct ata_device *dev = qc->dev;
4683 		struct ata_eh_info *ehi = &dev->link->eh_info;
4684 
4685 		WARN_ON(ap->pflags & ATA_PFLAG_FROZEN);
4686 
4687 		if (unlikely(qc->err_mask))
4688 			qc->flags |= ATA_QCFLAG_FAILED;
4689 
4690 		if (unlikely(qc->flags & ATA_QCFLAG_FAILED)) {
4691 			if (!ata_tag_internal(qc->tag)) {
4692 				/* always fill result TF for failed qc */
4693 				fill_result_tf(qc);
4694 				ata_qc_schedule_eh(qc);
4695 				return;
4696 			}
4697 		}
4698 
4699 		/* read result TF if requested */
4700 		if (qc->flags & ATA_QCFLAG_RESULT_TF)
4701 			fill_result_tf(qc);
4702 
4703 		/* Some commands need post-processing after successful
4704 		 * completion.
4705 		 */
4706 		switch (qc->tf.command) {
4707 		case ATA_CMD_SET_FEATURES:
4708 			if (qc->tf.feature != SETFEATURES_WC_ON &&
4709 			    qc->tf.feature != SETFEATURES_WC_OFF)
4710 				break;
4711 			/* fall through */
4712 		case ATA_CMD_INIT_DEV_PARAMS: /* CHS translation changed */
4713 		case ATA_CMD_SET_MULTI: /* multi_count changed */
4714 			/* revalidate device */
4715 			ehi->dev_action[dev->devno] |= ATA_EH_REVALIDATE;
4716 			ata_port_schedule_eh(ap);
4717 			break;
4718 
4719 		case ATA_CMD_SLEEP:
4720 			dev->flags |= ATA_DFLAG_SLEEPING;
4721 			break;
4722 		}
4723 
4724 		if (unlikely(dev->flags & ATA_DFLAG_DUBIOUS_XFER))
4725 			ata_verify_xfer(qc);
4726 
4727 		__ata_qc_complete(qc);
4728 	} else {
4729 		if (qc->flags & ATA_QCFLAG_EH_SCHEDULED)
4730 			return;
4731 
4732 		/* read result TF if failed or requested */
4733 		if (qc->err_mask || qc->flags & ATA_QCFLAG_RESULT_TF)
4734 			fill_result_tf(qc);
4735 
4736 		__ata_qc_complete(qc);
4737 	}
4738 }
4739 
4740 /**
4741  *	ata_qc_complete_multiple - Complete multiple qcs successfully
4742  *	@ap: port in question
4743  *	@qc_active: new qc_active mask
4744  *
4745  *	Complete in-flight commands.  This functions is meant to be
4746  *	called from low-level driver's interrupt routine to complete
4747  *	requests normally.  ap->qc_active and @qc_active is compared
4748  *	and commands are completed accordingly.
4749  *
4750  *	LOCKING:
4751  *	spin_lock_irqsave(host lock)
4752  *
4753  *	RETURNS:
4754  *	Number of completed commands on success, -errno otherwise.
4755  */
4756 int ata_qc_complete_multiple(struct ata_port *ap, u32 qc_active)
4757 {
4758 	int nr_done = 0;
4759 	u32 done_mask;
4760 	int i;
4761 
4762 	done_mask = ap->qc_active ^ qc_active;
4763 
4764 	if (unlikely(done_mask & qc_active)) {
4765 		ata_port_printk(ap, KERN_ERR, "illegal qc_active transition "
4766 				"(%08x->%08x)\n", ap->qc_active, qc_active);
4767 		return -EINVAL;
4768 	}
4769 
4770 	for (i = 0; i < ATA_MAX_QUEUE; i++) {
4771 		struct ata_queued_cmd *qc;
4772 
4773 		if (!(done_mask & (1 << i)))
4774 			continue;
4775 
4776 		if ((qc = ata_qc_from_tag(ap, i))) {
4777 			ata_qc_complete(qc);
4778 			nr_done++;
4779 		}
4780 	}
4781 
4782 	return nr_done;
4783 }
4784 
4785 /**
4786  *	ata_qc_issue - issue taskfile to device
4787  *	@qc: command to issue to device
4788  *
4789  *	Prepare an ATA command to submission to device.
4790  *	This includes mapping the data into a DMA-able
4791  *	area, filling in the S/G table, and finally
4792  *	writing the taskfile to hardware, starting the command.
4793  *
4794  *	LOCKING:
4795  *	spin_lock_irqsave(host lock)
4796  */
4797 void ata_qc_issue(struct ata_queued_cmd *qc)
4798 {
4799 	struct ata_port *ap = qc->ap;
4800 	struct ata_link *link = qc->dev->link;
4801 	u8 prot = qc->tf.protocol;
4802 
4803 	/* Make sure only one non-NCQ command is outstanding.  The
4804 	 * check is skipped for old EH because it reuses active qc to
4805 	 * request ATAPI sense.
4806 	 */
4807 	WARN_ON(ap->ops->error_handler && ata_tag_valid(link->active_tag));
4808 
4809 	if (ata_is_ncq(prot)) {
4810 		WARN_ON(link->sactive & (1 << qc->tag));
4811 
4812 		if (!link->sactive)
4813 			ap->nr_active_links++;
4814 		link->sactive |= 1 << qc->tag;
4815 	} else {
4816 		WARN_ON(link->sactive);
4817 
4818 		ap->nr_active_links++;
4819 		link->active_tag = qc->tag;
4820 	}
4821 
4822 	qc->flags |= ATA_QCFLAG_ACTIVE;
4823 	ap->qc_active |= 1 << qc->tag;
4824 
4825 	/* We guarantee to LLDs that they will have at least one
4826 	 * non-zero sg if the command is a data command.
4827 	 */
4828 	BUG_ON(ata_is_data(prot) && (!qc->sg || !qc->n_elem || !qc->nbytes));
4829 
4830 	if (ata_is_dma(prot) || (ata_is_pio(prot) &&
4831 				 (ap->flags & ATA_FLAG_PIO_DMA)))
4832 		if (ata_sg_setup(qc))
4833 			goto sg_err;
4834 
4835 	/* if device is sleeping, schedule reset and abort the link */
4836 	if (unlikely(qc->dev->flags & ATA_DFLAG_SLEEPING)) {
4837 		link->eh_info.action |= ATA_EH_RESET;
4838 		ata_ehi_push_desc(&link->eh_info, "waking up from sleep");
4839 		ata_link_abort(link);
4840 		return;
4841 	}
4842 
4843 	ap->ops->qc_prep(qc);
4844 
4845 	qc->err_mask |= ap->ops->qc_issue(qc);
4846 	if (unlikely(qc->err_mask))
4847 		goto err;
4848 	return;
4849 
4850 sg_err:
4851 	qc->err_mask |= AC_ERR_SYSTEM;
4852 err:
4853 	ata_qc_complete(qc);
4854 }
4855 
4856 /**
4857  *	sata_scr_valid - test whether SCRs are accessible
4858  *	@link: ATA link to test SCR accessibility for
4859  *
4860  *	Test whether SCRs are accessible for @link.
4861  *
4862  *	LOCKING:
4863  *	None.
4864  *
4865  *	RETURNS:
4866  *	1 if SCRs are accessible, 0 otherwise.
4867  */
4868 int sata_scr_valid(struct ata_link *link)
4869 {
4870 	struct ata_port *ap = link->ap;
4871 
4872 	return (ap->flags & ATA_FLAG_SATA) && ap->ops->scr_read;
4873 }
4874 
4875 /**
4876  *	sata_scr_read - read SCR register of the specified port
4877  *	@link: ATA link to read SCR for
4878  *	@reg: SCR to read
4879  *	@val: Place to store read value
4880  *
4881  *	Read SCR register @reg of @link into *@val.  This function is
4882  *	guaranteed to succeed if @link is ap->link, the cable type of
4883  *	the port is SATA and the port implements ->scr_read.
4884  *
4885  *	LOCKING:
4886  *	None if @link is ap->link.  Kernel thread context otherwise.
4887  *
4888  *	RETURNS:
4889  *	0 on success, negative errno on failure.
4890  */
4891 int sata_scr_read(struct ata_link *link, int reg, u32 *val)
4892 {
4893 	if (ata_is_host_link(link)) {
4894 		if (sata_scr_valid(link))
4895 			return link->ap->ops->scr_read(link, reg, val);
4896 		return -EOPNOTSUPP;
4897 	}
4898 
4899 	return sata_pmp_scr_read(link, reg, val);
4900 }
4901 
4902 /**
4903  *	sata_scr_write - write SCR register of the specified port
4904  *	@link: ATA link to write SCR for
4905  *	@reg: SCR to write
4906  *	@val: value to write
4907  *
4908  *	Write @val to SCR register @reg of @link.  This function is
4909  *	guaranteed to succeed if @link is ap->link, the cable type of
4910  *	the port is SATA and the port implements ->scr_read.
4911  *
4912  *	LOCKING:
4913  *	None if @link is ap->link.  Kernel thread context otherwise.
4914  *
4915  *	RETURNS:
4916  *	0 on success, negative errno on failure.
4917  */
4918 int sata_scr_write(struct ata_link *link, int reg, u32 val)
4919 {
4920 	if (ata_is_host_link(link)) {
4921 		if (sata_scr_valid(link))
4922 			return link->ap->ops->scr_write(link, reg, val);
4923 		return -EOPNOTSUPP;
4924 	}
4925 
4926 	return sata_pmp_scr_write(link, reg, val);
4927 }
4928 
4929 /**
4930  *	sata_scr_write_flush - write SCR register of the specified port and flush
4931  *	@link: ATA link to write SCR for
4932  *	@reg: SCR to write
4933  *	@val: value to write
4934  *
4935  *	This function is identical to sata_scr_write() except that this
4936  *	function performs flush after writing to the register.
4937  *
4938  *	LOCKING:
4939  *	None if @link is ap->link.  Kernel thread context otherwise.
4940  *
4941  *	RETURNS:
4942  *	0 on success, negative errno on failure.
4943  */
4944 int sata_scr_write_flush(struct ata_link *link, int reg, u32 val)
4945 {
4946 	if (ata_is_host_link(link)) {
4947 		int rc;
4948 
4949 		if (sata_scr_valid(link)) {
4950 			rc = link->ap->ops->scr_write(link, reg, val);
4951 			if (rc == 0)
4952 				rc = link->ap->ops->scr_read(link, reg, &val);
4953 			return rc;
4954 		}
4955 		return -EOPNOTSUPP;
4956 	}
4957 
4958 	return sata_pmp_scr_write(link, reg, val);
4959 }
4960 
4961 /**
4962  *	ata_phys_link_online - test whether the given link is online
4963  *	@link: ATA link to test
4964  *
4965  *	Test whether @link is online.  Note that this function returns
4966  *	0 if online status of @link cannot be obtained, so
4967  *	ata_link_online(link) != !ata_link_offline(link).
4968  *
4969  *	LOCKING:
4970  *	None.
4971  *
4972  *	RETURNS:
4973  *	True if the port online status is available and online.
4974  */
4975 bool ata_phys_link_online(struct ata_link *link)
4976 {
4977 	u32 sstatus;
4978 
4979 	if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0 &&
4980 	    (sstatus & 0xf) == 0x3)
4981 		return true;
4982 	return false;
4983 }
4984 
4985 /**
4986  *	ata_phys_link_offline - test whether the given link is offline
4987  *	@link: ATA link to test
4988  *
4989  *	Test whether @link is offline.  Note that this function
4990  *	returns 0 if offline status of @link cannot be obtained, so
4991  *	ata_link_online(link) != !ata_link_offline(link).
4992  *
4993  *	LOCKING:
4994  *	None.
4995  *
4996  *	RETURNS:
4997  *	True if the port offline status is available and offline.
4998  */
4999 bool ata_phys_link_offline(struct ata_link *link)
5000 {
5001 	u32 sstatus;
5002 
5003 	if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0 &&
5004 	    (sstatus & 0xf) != 0x3)
5005 		return true;
5006 	return false;
5007 }
5008 
5009 /**
5010  *	ata_link_online - test whether the given link is online
5011  *	@link: ATA link to test
5012  *
5013  *	Test whether @link is online.  This is identical to
5014  *	ata_phys_link_online() when there's no slave link.  When
5015  *	there's a slave link, this function should only be called on
5016  *	the master link and will return true if any of M/S links is
5017  *	online.
5018  *
5019  *	LOCKING:
5020  *	None.
5021  *
5022  *	RETURNS:
5023  *	True if the port online status is available and online.
5024  */
5025 bool ata_link_online(struct ata_link *link)
5026 {
5027 	struct ata_link *slave = link->ap->slave_link;
5028 
5029 	WARN_ON(link == slave);	/* shouldn't be called on slave link */
5030 
5031 	return ata_phys_link_online(link) ||
5032 		(slave && ata_phys_link_online(slave));
5033 }
5034 
5035 /**
5036  *	ata_link_offline - test whether the given link is offline
5037  *	@link: ATA link to test
5038  *
5039  *	Test whether @link is offline.  This is identical to
5040  *	ata_phys_link_offline() when there's no slave link.  When
5041  *	there's a slave link, this function should only be called on
5042  *	the master link and will return true if both M/S links are
5043  *	offline.
5044  *
5045  *	LOCKING:
5046  *	None.
5047  *
5048  *	RETURNS:
5049  *	True if the port offline status is available and offline.
5050  */
5051 bool ata_link_offline(struct ata_link *link)
5052 {
5053 	struct ata_link *slave = link->ap->slave_link;
5054 
5055 	WARN_ON(link == slave);	/* shouldn't be called on slave link */
5056 
5057 	return ata_phys_link_offline(link) &&
5058 		(!slave || ata_phys_link_offline(slave));
5059 }
5060 
5061 #ifdef CONFIG_PM
5062 static int ata_host_request_pm(struct ata_host *host, pm_message_t mesg,
5063 			       unsigned int action, unsigned int ehi_flags,
5064 			       int wait)
5065 {
5066 	unsigned long flags;
5067 	int i, rc;
5068 
5069 	for (i = 0; i < host->n_ports; i++) {
5070 		struct ata_port *ap = host->ports[i];
5071 		struct ata_link *link;
5072 
5073 		/* Previous resume operation might still be in
5074 		 * progress.  Wait for PM_PENDING to clear.
5075 		 */
5076 		if (ap->pflags & ATA_PFLAG_PM_PENDING) {
5077 			ata_port_wait_eh(ap);
5078 			WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
5079 		}
5080 
5081 		/* request PM ops to EH */
5082 		spin_lock_irqsave(ap->lock, flags);
5083 
5084 		ap->pm_mesg = mesg;
5085 		if (wait) {
5086 			rc = 0;
5087 			ap->pm_result = &rc;
5088 		}
5089 
5090 		ap->pflags |= ATA_PFLAG_PM_PENDING;
5091 		__ata_port_for_each_link(link, ap) {
5092 			link->eh_info.action |= action;
5093 			link->eh_info.flags |= ehi_flags;
5094 		}
5095 
5096 		ata_port_schedule_eh(ap);
5097 
5098 		spin_unlock_irqrestore(ap->lock, flags);
5099 
5100 		/* wait and check result */
5101 		if (wait) {
5102 			ata_port_wait_eh(ap);
5103 			WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
5104 			if (rc)
5105 				return rc;
5106 		}
5107 	}
5108 
5109 	return 0;
5110 }
5111 
5112 /**
5113  *	ata_host_suspend - suspend host
5114  *	@host: host to suspend
5115  *	@mesg: PM message
5116  *
5117  *	Suspend @host.  Actual operation is performed by EH.  This
5118  *	function requests EH to perform PM operations and waits for EH
5119  *	to finish.
5120  *
5121  *	LOCKING:
5122  *	Kernel thread context (may sleep).
5123  *
5124  *	RETURNS:
5125  *	0 on success, -errno on failure.
5126  */
5127 int ata_host_suspend(struct ata_host *host, pm_message_t mesg)
5128 {
5129 	int rc;
5130 
5131 	/*
5132 	 * disable link pm on all ports before requesting
5133 	 * any pm activity
5134 	 */
5135 	ata_lpm_enable(host);
5136 
5137 	rc = ata_host_request_pm(host, mesg, 0, ATA_EHI_QUIET, 1);
5138 	if (rc == 0)
5139 		host->dev->power.power_state = mesg;
5140 	return rc;
5141 }
5142 
5143 /**
5144  *	ata_host_resume - resume host
5145  *	@host: host to resume
5146  *
5147  *	Resume @host.  Actual operation is performed by EH.  This
5148  *	function requests EH to perform PM operations and returns.
5149  *	Note that all resume operations are performed parallely.
5150  *
5151  *	LOCKING:
5152  *	Kernel thread context (may sleep).
5153  */
5154 void ata_host_resume(struct ata_host *host)
5155 {
5156 	ata_host_request_pm(host, PMSG_ON, ATA_EH_RESET,
5157 			    ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET, 0);
5158 	host->dev->power.power_state = PMSG_ON;
5159 
5160 	/* reenable link pm */
5161 	ata_lpm_disable(host);
5162 }
5163 #endif
5164 
5165 /**
5166  *	ata_port_start - Set port up for dma.
5167  *	@ap: Port to initialize
5168  *
5169  *	Called just after data structures for each port are
5170  *	initialized.  Allocates space for PRD table.
5171  *
5172  *	May be used as the port_start() entry in ata_port_operations.
5173  *
5174  *	LOCKING:
5175  *	Inherited from caller.
5176  */
5177 int ata_port_start(struct ata_port *ap)
5178 {
5179 	struct device *dev = ap->dev;
5180 
5181 	ap->prd = dmam_alloc_coherent(dev, ATA_PRD_TBL_SZ, &ap->prd_dma,
5182 				      GFP_KERNEL);
5183 	if (!ap->prd)
5184 		return -ENOMEM;
5185 
5186 	return 0;
5187 }
5188 
5189 /**
5190  *	ata_dev_init - Initialize an ata_device structure
5191  *	@dev: Device structure to initialize
5192  *
5193  *	Initialize @dev in preparation for probing.
5194  *
5195  *	LOCKING:
5196  *	Inherited from caller.
5197  */
5198 void ata_dev_init(struct ata_device *dev)
5199 {
5200 	struct ata_link *link = ata_dev_phys_link(dev);
5201 	struct ata_port *ap = link->ap;
5202 	unsigned long flags;
5203 
5204 	/* SATA spd limit is bound to the attached device, reset together */
5205 	link->sata_spd_limit = link->hw_sata_spd_limit;
5206 	link->sata_spd = 0;
5207 
5208 	/* High bits of dev->flags are used to record warm plug
5209 	 * requests which occur asynchronously.  Synchronize using
5210 	 * host lock.
5211 	 */
5212 	spin_lock_irqsave(ap->lock, flags);
5213 	dev->flags &= ~ATA_DFLAG_INIT_MASK;
5214 	dev->horkage = 0;
5215 	spin_unlock_irqrestore(ap->lock, flags);
5216 
5217 	memset((void *)dev + ATA_DEVICE_CLEAR_OFFSET, 0,
5218 	       sizeof(*dev) - ATA_DEVICE_CLEAR_OFFSET);
5219 	dev->pio_mask = UINT_MAX;
5220 	dev->mwdma_mask = UINT_MAX;
5221 	dev->udma_mask = UINT_MAX;
5222 }
5223 
5224 /**
5225  *	ata_link_init - Initialize an ata_link structure
5226  *	@ap: ATA port link is attached to
5227  *	@link: Link structure to initialize
5228  *	@pmp: Port multiplier port number
5229  *
5230  *	Initialize @link.
5231  *
5232  *	LOCKING:
5233  *	Kernel thread context (may sleep)
5234  */
5235 void ata_link_init(struct ata_port *ap, struct ata_link *link, int pmp)
5236 {
5237 	int i;
5238 
5239 	/* clear everything except for devices */
5240 	memset(link, 0, offsetof(struct ata_link, device[0]));
5241 
5242 	link->ap = ap;
5243 	link->pmp = pmp;
5244 	link->active_tag = ATA_TAG_POISON;
5245 	link->hw_sata_spd_limit = UINT_MAX;
5246 
5247 	/* can't use iterator, ap isn't initialized yet */
5248 	for (i = 0; i < ATA_MAX_DEVICES; i++) {
5249 		struct ata_device *dev = &link->device[i];
5250 
5251 		dev->link = link;
5252 		dev->devno = dev - link->device;
5253 		ata_dev_init(dev);
5254 	}
5255 }
5256 
5257 /**
5258  *	sata_link_init_spd - Initialize link->sata_spd_limit
5259  *	@link: Link to configure sata_spd_limit for
5260  *
5261  *	Initialize @link->[hw_]sata_spd_limit to the currently
5262  *	configured value.
5263  *
5264  *	LOCKING:
5265  *	Kernel thread context (may sleep).
5266  *
5267  *	RETURNS:
5268  *	0 on success, -errno on failure.
5269  */
5270 int sata_link_init_spd(struct ata_link *link)
5271 {
5272 	u8 spd;
5273 	int rc;
5274 
5275 	rc = sata_scr_read(link, SCR_CONTROL, &link->saved_scontrol);
5276 	if (rc)
5277 		return rc;
5278 
5279 	spd = (link->saved_scontrol >> 4) & 0xf;
5280 	if (spd)
5281 		link->hw_sata_spd_limit &= (1 << spd) - 1;
5282 
5283 	ata_force_link_limits(link);
5284 
5285 	link->sata_spd_limit = link->hw_sata_spd_limit;
5286 
5287 	return 0;
5288 }
5289 
5290 /**
5291  *	ata_port_alloc - allocate and initialize basic ATA port resources
5292  *	@host: ATA host this allocated port belongs to
5293  *
5294  *	Allocate and initialize basic ATA port resources.
5295  *
5296  *	RETURNS:
5297  *	Allocate ATA port on success, NULL on failure.
5298  *
5299  *	LOCKING:
5300  *	Inherited from calling layer (may sleep).
5301  */
5302 struct ata_port *ata_port_alloc(struct ata_host *host)
5303 {
5304 	struct ata_port *ap;
5305 
5306 	DPRINTK("ENTER\n");
5307 
5308 	ap = kzalloc(sizeof(*ap), GFP_KERNEL);
5309 	if (!ap)
5310 		return NULL;
5311 
5312 	ap->pflags |= ATA_PFLAG_INITIALIZING;
5313 	ap->lock = &host->lock;
5314 	ap->flags = ATA_FLAG_DISABLED;
5315 	ap->print_id = -1;
5316 	ap->ctl = ATA_DEVCTL_OBS;
5317 	ap->host = host;
5318 	ap->dev = host->dev;
5319 	ap->last_ctl = 0xFF;
5320 
5321 #if defined(ATA_VERBOSE_DEBUG)
5322 	/* turn on all debugging levels */
5323 	ap->msg_enable = 0x00FF;
5324 #elif defined(ATA_DEBUG)
5325 	ap->msg_enable = ATA_MSG_DRV | ATA_MSG_INFO | ATA_MSG_CTL | ATA_MSG_WARN | ATA_MSG_ERR;
5326 #else
5327 	ap->msg_enable = ATA_MSG_DRV | ATA_MSG_ERR | ATA_MSG_WARN;
5328 #endif
5329 
5330 #ifdef CONFIG_ATA_SFF
5331 	INIT_DELAYED_WORK(&ap->port_task, ata_pio_task);
5332 #else
5333 	INIT_DELAYED_WORK(&ap->port_task, NULL);
5334 #endif
5335 	INIT_DELAYED_WORK(&ap->hotplug_task, ata_scsi_hotplug);
5336 	INIT_WORK(&ap->scsi_rescan_task, ata_scsi_dev_rescan);
5337 	INIT_LIST_HEAD(&ap->eh_done_q);
5338 	init_waitqueue_head(&ap->eh_wait_q);
5339 	init_completion(&ap->park_req_pending);
5340 	init_timer_deferrable(&ap->fastdrain_timer);
5341 	ap->fastdrain_timer.function = ata_eh_fastdrain_timerfn;
5342 	ap->fastdrain_timer.data = (unsigned long)ap;
5343 
5344 	ap->cbl = ATA_CBL_NONE;
5345 
5346 	ata_link_init(ap, &ap->link, 0);
5347 
5348 #ifdef ATA_IRQ_TRAP
5349 	ap->stats.unhandled_irq = 1;
5350 	ap->stats.idle_irq = 1;
5351 #endif
5352 	return ap;
5353 }
5354 
5355 static void ata_host_release(struct device *gendev, void *res)
5356 {
5357 	struct ata_host *host = dev_get_drvdata(gendev);
5358 	int i;
5359 
5360 	for (i = 0; i < host->n_ports; i++) {
5361 		struct ata_port *ap = host->ports[i];
5362 
5363 		if (!ap)
5364 			continue;
5365 
5366 		if (ap->scsi_host)
5367 			scsi_host_put(ap->scsi_host);
5368 
5369 		kfree(ap->pmp_link);
5370 		kfree(ap->slave_link);
5371 		kfree(ap);
5372 		host->ports[i] = NULL;
5373 	}
5374 
5375 	dev_set_drvdata(gendev, NULL);
5376 }
5377 
5378 /**
5379  *	ata_host_alloc - allocate and init basic ATA host resources
5380  *	@dev: generic device this host is associated with
5381  *	@max_ports: maximum number of ATA ports associated with this host
5382  *
5383  *	Allocate and initialize basic ATA host resources.  LLD calls
5384  *	this function to allocate a host, initializes it fully and
5385  *	attaches it using ata_host_register().
5386  *
5387  *	@max_ports ports are allocated and host->n_ports is
5388  *	initialized to @max_ports.  The caller is allowed to decrease
5389  *	host->n_ports before calling ata_host_register().  The unused
5390  *	ports will be automatically freed on registration.
5391  *
5392  *	RETURNS:
5393  *	Allocate ATA host on success, NULL on failure.
5394  *
5395  *	LOCKING:
5396  *	Inherited from calling layer (may sleep).
5397  */
5398 struct ata_host *ata_host_alloc(struct device *dev, int max_ports)
5399 {
5400 	struct ata_host *host;
5401 	size_t sz;
5402 	int i;
5403 
5404 	DPRINTK("ENTER\n");
5405 
5406 	if (!devres_open_group(dev, NULL, GFP_KERNEL))
5407 		return NULL;
5408 
5409 	/* alloc a container for our list of ATA ports (buses) */
5410 	sz = sizeof(struct ata_host) + (max_ports + 1) * sizeof(void *);
5411 	/* alloc a container for our list of ATA ports (buses) */
5412 	host = devres_alloc(ata_host_release, sz, GFP_KERNEL);
5413 	if (!host)
5414 		goto err_out;
5415 
5416 	devres_add(dev, host);
5417 	dev_set_drvdata(dev, host);
5418 
5419 	spin_lock_init(&host->lock);
5420 	host->dev = dev;
5421 	host->n_ports = max_ports;
5422 
5423 	/* allocate ports bound to this host */
5424 	for (i = 0; i < max_ports; i++) {
5425 		struct ata_port *ap;
5426 
5427 		ap = ata_port_alloc(host);
5428 		if (!ap)
5429 			goto err_out;
5430 
5431 		ap->port_no = i;
5432 		host->ports[i] = ap;
5433 	}
5434 
5435 	devres_remove_group(dev, NULL);
5436 	return host;
5437 
5438  err_out:
5439 	devres_release_group(dev, NULL);
5440 	return NULL;
5441 }
5442 
5443 /**
5444  *	ata_host_alloc_pinfo - alloc host and init with port_info array
5445  *	@dev: generic device this host is associated with
5446  *	@ppi: array of ATA port_info to initialize host with
5447  *	@n_ports: number of ATA ports attached to this host
5448  *
5449  *	Allocate ATA host and initialize with info from @ppi.  If NULL
5450  *	terminated, @ppi may contain fewer entries than @n_ports.  The
5451  *	last entry will be used for the remaining ports.
5452  *
5453  *	RETURNS:
5454  *	Allocate ATA host on success, NULL on failure.
5455  *
5456  *	LOCKING:
5457  *	Inherited from calling layer (may sleep).
5458  */
5459 struct ata_host *ata_host_alloc_pinfo(struct device *dev,
5460 				      const struct ata_port_info * const * ppi,
5461 				      int n_ports)
5462 {
5463 	const struct ata_port_info *pi;
5464 	struct ata_host *host;
5465 	int i, j;
5466 
5467 	host = ata_host_alloc(dev, n_ports);
5468 	if (!host)
5469 		return NULL;
5470 
5471 	for (i = 0, j = 0, pi = NULL; i < host->n_ports; i++) {
5472 		struct ata_port *ap = host->ports[i];
5473 
5474 		if (ppi[j])
5475 			pi = ppi[j++];
5476 
5477 		ap->pio_mask = pi->pio_mask;
5478 		ap->mwdma_mask = pi->mwdma_mask;
5479 		ap->udma_mask = pi->udma_mask;
5480 		ap->flags |= pi->flags;
5481 		ap->link.flags |= pi->link_flags;
5482 		ap->ops = pi->port_ops;
5483 
5484 		if (!host->ops && (pi->port_ops != &ata_dummy_port_ops))
5485 			host->ops = pi->port_ops;
5486 	}
5487 
5488 	return host;
5489 }
5490 
5491 /**
5492  *	ata_slave_link_init - initialize slave link
5493  *	@ap: port to initialize slave link for
5494  *
5495  *	Create and initialize slave link for @ap.  This enables slave
5496  *	link handling on the port.
5497  *
5498  *	In libata, a port contains links and a link contains devices.
5499  *	There is single host link but if a PMP is attached to it,
5500  *	there can be multiple fan-out links.  On SATA, there's usually
5501  *	a single device connected to a link but PATA and SATA
5502  *	controllers emulating TF based interface can have two - master
5503  *	and slave.
5504  *
5505  *	However, there are a few controllers which don't fit into this
5506  *	abstraction too well - SATA controllers which emulate TF
5507  *	interface with both master and slave devices but also have
5508  *	separate SCR register sets for each device.  These controllers
5509  *	need separate links for physical link handling
5510  *	(e.g. onlineness, link speed) but should be treated like a
5511  *	traditional M/S controller for everything else (e.g. command
5512  *	issue, softreset).
5513  *
5514  *	slave_link is libata's way of handling this class of
5515  *	controllers without impacting core layer too much.  For
5516  *	anything other than physical link handling, the default host
5517  *	link is used for both master and slave.  For physical link
5518  *	handling, separate @ap->slave_link is used.  All dirty details
5519  *	are implemented inside libata core layer.  From LLD's POV, the
5520  *	only difference is that prereset, hardreset and postreset are
5521  *	called once more for the slave link, so the reset sequence
5522  *	looks like the following.
5523  *
5524  *	prereset(M) -> prereset(S) -> hardreset(M) -> hardreset(S) ->
5525  *	softreset(M) -> postreset(M) -> postreset(S)
5526  *
5527  *	Note that softreset is called only for the master.  Softreset
5528  *	resets both M/S by definition, so SRST on master should handle
5529  *	both (the standard method will work just fine).
5530  *
5531  *	LOCKING:
5532  *	Should be called before host is registered.
5533  *
5534  *	RETURNS:
5535  *	0 on success, -errno on failure.
5536  */
5537 int ata_slave_link_init(struct ata_port *ap)
5538 {
5539 	struct ata_link *link;
5540 
5541 	WARN_ON(ap->slave_link);
5542 	WARN_ON(ap->flags & ATA_FLAG_PMP);
5543 
5544 	link = kzalloc(sizeof(*link), GFP_KERNEL);
5545 	if (!link)
5546 		return -ENOMEM;
5547 
5548 	ata_link_init(ap, link, 1);
5549 	ap->slave_link = link;
5550 	return 0;
5551 }
5552 
5553 static void ata_host_stop(struct device *gendev, void *res)
5554 {
5555 	struct ata_host *host = dev_get_drvdata(gendev);
5556 	int i;
5557 
5558 	WARN_ON(!(host->flags & ATA_HOST_STARTED));
5559 
5560 	for (i = 0; i < host->n_ports; i++) {
5561 		struct ata_port *ap = host->ports[i];
5562 
5563 		if (ap->ops->port_stop)
5564 			ap->ops->port_stop(ap);
5565 	}
5566 
5567 	if (host->ops->host_stop)
5568 		host->ops->host_stop(host);
5569 }
5570 
5571 /**
5572  *	ata_finalize_port_ops - finalize ata_port_operations
5573  *	@ops: ata_port_operations to finalize
5574  *
5575  *	An ata_port_operations can inherit from another ops and that
5576  *	ops can again inherit from another.  This can go on as many
5577  *	times as necessary as long as there is no loop in the
5578  *	inheritance chain.
5579  *
5580  *	Ops tables are finalized when the host is started.  NULL or
5581  *	unspecified entries are inherited from the closet ancestor
5582  *	which has the method and the entry is populated with it.
5583  *	After finalization, the ops table directly points to all the
5584  *	methods and ->inherits is no longer necessary and cleared.
5585  *
5586  *	Using ATA_OP_NULL, inheriting ops can force a method to NULL.
5587  *
5588  *	LOCKING:
5589  *	None.
5590  */
5591 static void ata_finalize_port_ops(struct ata_port_operations *ops)
5592 {
5593 	static DEFINE_SPINLOCK(lock);
5594 	const struct ata_port_operations *cur;
5595 	void **begin = (void **)ops;
5596 	void **end = (void **)&ops->inherits;
5597 	void **pp;
5598 
5599 	if (!ops || !ops->inherits)
5600 		return;
5601 
5602 	spin_lock(&lock);
5603 
5604 	for (cur = ops->inherits; cur; cur = cur->inherits) {
5605 		void **inherit = (void **)cur;
5606 
5607 		for (pp = begin; pp < end; pp++, inherit++)
5608 			if (!*pp)
5609 				*pp = *inherit;
5610 	}
5611 
5612 	for (pp = begin; pp < end; pp++)
5613 		if (IS_ERR(*pp))
5614 			*pp = NULL;
5615 
5616 	ops->inherits = NULL;
5617 
5618 	spin_unlock(&lock);
5619 }
5620 
5621 /**
5622  *	ata_host_start - start and freeze ports of an ATA host
5623  *	@host: ATA host to start ports for
5624  *
5625  *	Start and then freeze ports of @host.  Started status is
5626  *	recorded in host->flags, so this function can be called
5627  *	multiple times.  Ports are guaranteed to get started only
5628  *	once.  If host->ops isn't initialized yet, its set to the
5629  *	first non-dummy port ops.
5630  *
5631  *	LOCKING:
5632  *	Inherited from calling layer (may sleep).
5633  *
5634  *	RETURNS:
5635  *	0 if all ports are started successfully, -errno otherwise.
5636  */
5637 int ata_host_start(struct ata_host *host)
5638 {
5639 	int have_stop = 0;
5640 	void *start_dr = NULL;
5641 	int i, rc;
5642 
5643 	if (host->flags & ATA_HOST_STARTED)
5644 		return 0;
5645 
5646 	ata_finalize_port_ops(host->ops);
5647 
5648 	for (i = 0; i < host->n_ports; i++) {
5649 		struct ata_port *ap = host->ports[i];
5650 
5651 		ata_finalize_port_ops(ap->ops);
5652 
5653 		if (!host->ops && !ata_port_is_dummy(ap))
5654 			host->ops = ap->ops;
5655 
5656 		if (ap->ops->port_stop)
5657 			have_stop = 1;
5658 	}
5659 
5660 	if (host->ops->host_stop)
5661 		have_stop = 1;
5662 
5663 	if (have_stop) {
5664 		start_dr = devres_alloc(ata_host_stop, 0, GFP_KERNEL);
5665 		if (!start_dr)
5666 			return -ENOMEM;
5667 	}
5668 
5669 	for (i = 0; i < host->n_ports; i++) {
5670 		struct ata_port *ap = host->ports[i];
5671 
5672 		if (ap->ops->port_start) {
5673 			rc = ap->ops->port_start(ap);
5674 			if (rc) {
5675 				if (rc != -ENODEV)
5676 					dev_printk(KERN_ERR, host->dev,
5677 						"failed to start port %d "
5678 						"(errno=%d)\n", i, rc);
5679 				goto err_out;
5680 			}
5681 		}
5682 		ata_eh_freeze_port(ap);
5683 	}
5684 
5685 	if (start_dr)
5686 		devres_add(host->dev, start_dr);
5687 	host->flags |= ATA_HOST_STARTED;
5688 	return 0;
5689 
5690  err_out:
5691 	while (--i >= 0) {
5692 		struct ata_port *ap = host->ports[i];
5693 
5694 		if (ap->ops->port_stop)
5695 			ap->ops->port_stop(ap);
5696 	}
5697 	devres_free(start_dr);
5698 	return rc;
5699 }
5700 
5701 /**
5702  *	ata_sas_host_init - Initialize a host struct
5703  *	@host:	host to initialize
5704  *	@dev:	device host is attached to
5705  *	@flags:	host flags
5706  *	@ops:	port_ops
5707  *
5708  *	LOCKING:
5709  *	PCI/etc. bus probe sem.
5710  *
5711  */
5712 /* KILLME - the only user left is ipr */
5713 void ata_host_init(struct ata_host *host, struct device *dev,
5714 		   unsigned long flags, struct ata_port_operations *ops)
5715 {
5716 	spin_lock_init(&host->lock);
5717 	host->dev = dev;
5718 	host->flags = flags;
5719 	host->ops = ops;
5720 }
5721 
5722 /**
5723  *	ata_host_register - register initialized ATA host
5724  *	@host: ATA host to register
5725  *	@sht: template for SCSI host
5726  *
5727  *	Register initialized ATA host.  @host is allocated using
5728  *	ata_host_alloc() and fully initialized by LLD.  This function
5729  *	starts ports, registers @host with ATA and SCSI layers and
5730  *	probe registered devices.
5731  *
5732  *	LOCKING:
5733  *	Inherited from calling layer (may sleep).
5734  *
5735  *	RETURNS:
5736  *	0 on success, -errno otherwise.
5737  */
5738 int ata_host_register(struct ata_host *host, struct scsi_host_template *sht)
5739 {
5740 	int i, rc;
5741 
5742 	/* host must have been started */
5743 	if (!(host->flags & ATA_HOST_STARTED)) {
5744 		dev_printk(KERN_ERR, host->dev,
5745 			   "BUG: trying to register unstarted host\n");
5746 		WARN_ON(1);
5747 		return -EINVAL;
5748 	}
5749 
5750 	/* Blow away unused ports.  This happens when LLD can't
5751 	 * determine the exact number of ports to allocate at
5752 	 * allocation time.
5753 	 */
5754 	for (i = host->n_ports; host->ports[i]; i++)
5755 		kfree(host->ports[i]);
5756 
5757 	/* give ports names and add SCSI hosts */
5758 	for (i = 0; i < host->n_ports; i++)
5759 		host->ports[i]->print_id = ata_print_id++;
5760 
5761 	rc = ata_scsi_add_hosts(host, sht);
5762 	if (rc)
5763 		return rc;
5764 
5765 	/* associate with ACPI nodes */
5766 	ata_acpi_associate(host);
5767 
5768 	/* set cable, sata_spd_limit and report */
5769 	for (i = 0; i < host->n_ports; i++) {
5770 		struct ata_port *ap = host->ports[i];
5771 		unsigned long xfer_mask;
5772 
5773 		/* set SATA cable type if still unset */
5774 		if (ap->cbl == ATA_CBL_NONE && (ap->flags & ATA_FLAG_SATA))
5775 			ap->cbl = ATA_CBL_SATA;
5776 
5777 		/* init sata_spd_limit to the current value */
5778 		sata_link_init_spd(&ap->link);
5779 		if (ap->slave_link)
5780 			sata_link_init_spd(ap->slave_link);
5781 
5782 		/* print per-port info to dmesg */
5783 		xfer_mask = ata_pack_xfermask(ap->pio_mask, ap->mwdma_mask,
5784 					      ap->udma_mask);
5785 
5786 		if (!ata_port_is_dummy(ap)) {
5787 			ata_port_printk(ap, KERN_INFO,
5788 					"%cATA max %s %s\n",
5789 					(ap->flags & ATA_FLAG_SATA) ? 'S' : 'P',
5790 					ata_mode_string(xfer_mask),
5791 					ap->link.eh_info.desc);
5792 			ata_ehi_clear_desc(&ap->link.eh_info);
5793 		} else
5794 			ata_port_printk(ap, KERN_INFO, "DUMMY\n");
5795 	}
5796 
5797 	/* perform each probe synchronously */
5798 	DPRINTK("probe begin\n");
5799 	for (i = 0; i < host->n_ports; i++) {
5800 		struct ata_port *ap = host->ports[i];
5801 
5802 		/* probe */
5803 		if (ap->ops->error_handler) {
5804 			struct ata_eh_info *ehi = &ap->link.eh_info;
5805 			unsigned long flags;
5806 
5807 			ata_port_probe(ap);
5808 
5809 			/* kick EH for boot probing */
5810 			spin_lock_irqsave(ap->lock, flags);
5811 
5812 			ehi->probe_mask |= ATA_ALL_DEVICES;
5813 			ehi->action |= ATA_EH_RESET | ATA_EH_LPM;
5814 			ehi->flags |= ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET;
5815 
5816 			ap->pflags &= ~ATA_PFLAG_INITIALIZING;
5817 			ap->pflags |= ATA_PFLAG_LOADING;
5818 			ata_port_schedule_eh(ap);
5819 
5820 			spin_unlock_irqrestore(ap->lock, flags);
5821 
5822 			/* wait for EH to finish */
5823 			ata_port_wait_eh(ap);
5824 		} else {
5825 			DPRINTK("ata%u: bus probe begin\n", ap->print_id);
5826 			rc = ata_bus_probe(ap);
5827 			DPRINTK("ata%u: bus probe end\n", ap->print_id);
5828 
5829 			if (rc) {
5830 				/* FIXME: do something useful here?
5831 				 * Current libata behavior will
5832 				 * tear down everything when
5833 				 * the module is removed
5834 				 * or the h/w is unplugged.
5835 				 */
5836 			}
5837 		}
5838 	}
5839 
5840 	/* probes are done, now scan each port's disk(s) */
5841 	DPRINTK("host probe begin\n");
5842 	for (i = 0; i < host->n_ports; i++) {
5843 		struct ata_port *ap = host->ports[i];
5844 
5845 		ata_scsi_scan_host(ap, 1);
5846 	}
5847 
5848 	return 0;
5849 }
5850 
5851 /**
5852  *	ata_host_activate - start host, request IRQ and register it
5853  *	@host: target ATA host
5854  *	@irq: IRQ to request
5855  *	@irq_handler: irq_handler used when requesting IRQ
5856  *	@irq_flags: irq_flags used when requesting IRQ
5857  *	@sht: scsi_host_template to use when registering the host
5858  *
5859  *	After allocating an ATA host and initializing it, most libata
5860  *	LLDs perform three steps to activate the host - start host,
5861  *	request IRQ and register it.  This helper takes necessasry
5862  *	arguments and performs the three steps in one go.
5863  *
5864  *	An invalid IRQ skips the IRQ registration and expects the host to
5865  *	have set polling mode on the port. In this case, @irq_handler
5866  *	should be NULL.
5867  *
5868  *	LOCKING:
5869  *	Inherited from calling layer (may sleep).
5870  *
5871  *	RETURNS:
5872  *	0 on success, -errno otherwise.
5873  */
5874 int ata_host_activate(struct ata_host *host, int irq,
5875 		      irq_handler_t irq_handler, unsigned long irq_flags,
5876 		      struct scsi_host_template *sht)
5877 {
5878 	int i, rc;
5879 
5880 	rc = ata_host_start(host);
5881 	if (rc)
5882 		return rc;
5883 
5884 	/* Special case for polling mode */
5885 	if (!irq) {
5886 		WARN_ON(irq_handler);
5887 		return ata_host_register(host, sht);
5888 	}
5889 
5890 	rc = devm_request_irq(host->dev, irq, irq_handler, irq_flags,
5891 			      dev_driver_string(host->dev), host);
5892 	if (rc)
5893 		return rc;
5894 
5895 	for (i = 0; i < host->n_ports; i++)
5896 		ata_port_desc(host->ports[i], "irq %d", irq);
5897 
5898 	rc = ata_host_register(host, sht);
5899 	/* if failed, just free the IRQ and leave ports alone */
5900 	if (rc)
5901 		devm_free_irq(host->dev, irq, host);
5902 
5903 	return rc;
5904 }
5905 
5906 /**
5907  *	ata_port_detach - Detach ATA port in prepration of device removal
5908  *	@ap: ATA port to be detached
5909  *
5910  *	Detach all ATA devices and the associated SCSI devices of @ap;
5911  *	then, remove the associated SCSI host.  @ap is guaranteed to
5912  *	be quiescent on return from this function.
5913  *
5914  *	LOCKING:
5915  *	Kernel thread context (may sleep).
5916  */
5917 static void ata_port_detach(struct ata_port *ap)
5918 {
5919 	unsigned long flags;
5920 	struct ata_link *link;
5921 	struct ata_device *dev;
5922 
5923 	if (!ap->ops->error_handler)
5924 		goto skip_eh;
5925 
5926 	/* tell EH we're leaving & flush EH */
5927 	spin_lock_irqsave(ap->lock, flags);
5928 	ap->pflags |= ATA_PFLAG_UNLOADING;
5929 	spin_unlock_irqrestore(ap->lock, flags);
5930 
5931 	ata_port_wait_eh(ap);
5932 
5933 	/* EH is now guaranteed to see UNLOADING - EH context belongs
5934 	 * to us.  Restore SControl and disable all existing devices.
5935 	 */
5936 	__ata_port_for_each_link(link, ap) {
5937 		sata_scr_write(link, SCR_CONTROL, link->saved_scontrol);
5938 		ata_link_for_each_dev(dev, link)
5939 			ata_dev_disable(dev);
5940 	}
5941 
5942 	/* Final freeze & EH.  All in-flight commands are aborted.  EH
5943 	 * will be skipped and retrials will be terminated with bad
5944 	 * target.
5945 	 */
5946 	spin_lock_irqsave(ap->lock, flags);
5947 	ata_port_freeze(ap);	/* won't be thawed */
5948 	spin_unlock_irqrestore(ap->lock, flags);
5949 
5950 	ata_port_wait_eh(ap);
5951 	cancel_rearming_delayed_work(&ap->hotplug_task);
5952 
5953  skip_eh:
5954 	/* remove the associated SCSI host */
5955 	scsi_remove_host(ap->scsi_host);
5956 }
5957 
5958 /**
5959  *	ata_host_detach - Detach all ports of an ATA host
5960  *	@host: Host to detach
5961  *
5962  *	Detach all ports of @host.
5963  *
5964  *	LOCKING:
5965  *	Kernel thread context (may sleep).
5966  */
5967 void ata_host_detach(struct ata_host *host)
5968 {
5969 	int i;
5970 
5971 	for (i = 0; i < host->n_ports; i++)
5972 		ata_port_detach(host->ports[i]);
5973 
5974 	/* the host is dead now, dissociate ACPI */
5975 	ata_acpi_dissociate(host);
5976 }
5977 
5978 #ifdef CONFIG_PCI
5979 
5980 /**
5981  *	ata_pci_remove_one - PCI layer callback for device removal
5982  *	@pdev: PCI device that was removed
5983  *
5984  *	PCI layer indicates to libata via this hook that hot-unplug or
5985  *	module unload event has occurred.  Detach all ports.  Resource
5986  *	release is handled via devres.
5987  *
5988  *	LOCKING:
5989  *	Inherited from PCI layer (may sleep).
5990  */
5991 void ata_pci_remove_one(struct pci_dev *pdev)
5992 {
5993 	struct device *dev = &pdev->dev;
5994 	struct ata_host *host = dev_get_drvdata(dev);
5995 
5996 	ata_host_detach(host);
5997 }
5998 
5999 /* move to PCI subsystem */
6000 int pci_test_config_bits(struct pci_dev *pdev, const struct pci_bits *bits)
6001 {
6002 	unsigned long tmp = 0;
6003 
6004 	switch (bits->width) {
6005 	case 1: {
6006 		u8 tmp8 = 0;
6007 		pci_read_config_byte(pdev, bits->reg, &tmp8);
6008 		tmp = tmp8;
6009 		break;
6010 	}
6011 	case 2: {
6012 		u16 tmp16 = 0;
6013 		pci_read_config_word(pdev, bits->reg, &tmp16);
6014 		tmp = tmp16;
6015 		break;
6016 	}
6017 	case 4: {
6018 		u32 tmp32 = 0;
6019 		pci_read_config_dword(pdev, bits->reg, &tmp32);
6020 		tmp = tmp32;
6021 		break;
6022 	}
6023 
6024 	default:
6025 		return -EINVAL;
6026 	}
6027 
6028 	tmp &= bits->mask;
6029 
6030 	return (tmp == bits->val) ? 1 : 0;
6031 }
6032 
6033 #ifdef CONFIG_PM
6034 void ata_pci_device_do_suspend(struct pci_dev *pdev, pm_message_t mesg)
6035 {
6036 	pci_save_state(pdev);
6037 	pci_disable_device(pdev);
6038 
6039 	if (mesg.event & PM_EVENT_SLEEP)
6040 		pci_set_power_state(pdev, PCI_D3hot);
6041 }
6042 
6043 int ata_pci_device_do_resume(struct pci_dev *pdev)
6044 {
6045 	int rc;
6046 
6047 	pci_set_power_state(pdev, PCI_D0);
6048 	pci_restore_state(pdev);
6049 
6050 	rc = pcim_enable_device(pdev);
6051 	if (rc) {
6052 		dev_printk(KERN_ERR, &pdev->dev,
6053 			   "failed to enable device after resume (%d)\n", rc);
6054 		return rc;
6055 	}
6056 
6057 	pci_set_master(pdev);
6058 	return 0;
6059 }
6060 
6061 int ata_pci_device_suspend(struct pci_dev *pdev, pm_message_t mesg)
6062 {
6063 	struct ata_host *host = dev_get_drvdata(&pdev->dev);
6064 	int rc = 0;
6065 
6066 	rc = ata_host_suspend(host, mesg);
6067 	if (rc)
6068 		return rc;
6069 
6070 	ata_pci_device_do_suspend(pdev, mesg);
6071 
6072 	return 0;
6073 }
6074 
6075 int ata_pci_device_resume(struct pci_dev *pdev)
6076 {
6077 	struct ata_host *host = dev_get_drvdata(&pdev->dev);
6078 	int rc;
6079 
6080 	rc = ata_pci_device_do_resume(pdev);
6081 	if (rc == 0)
6082 		ata_host_resume(host);
6083 	return rc;
6084 }
6085 #endif /* CONFIG_PM */
6086 
6087 #endif /* CONFIG_PCI */
6088 
6089 static int __init ata_parse_force_one(char **cur,
6090 				      struct ata_force_ent *force_ent,
6091 				      const char **reason)
6092 {
6093 	/* FIXME: Currently, there's no way to tag init const data and
6094 	 * using __initdata causes build failure on some versions of
6095 	 * gcc.  Once __initdataconst is implemented, add const to the
6096 	 * following structure.
6097 	 */
6098 	static struct ata_force_param force_tbl[] __initdata = {
6099 		{ "40c",	.cbl		= ATA_CBL_PATA40 },
6100 		{ "80c",	.cbl		= ATA_CBL_PATA80 },
6101 		{ "short40c",	.cbl		= ATA_CBL_PATA40_SHORT },
6102 		{ "unk",	.cbl		= ATA_CBL_PATA_UNK },
6103 		{ "ign",	.cbl		= ATA_CBL_PATA_IGN },
6104 		{ "sata",	.cbl		= ATA_CBL_SATA },
6105 		{ "1.5Gbps",	.spd_limit	= 1 },
6106 		{ "3.0Gbps",	.spd_limit	= 2 },
6107 		{ "noncq",	.horkage_on	= ATA_HORKAGE_NONCQ },
6108 		{ "ncq",	.horkage_off	= ATA_HORKAGE_NONCQ },
6109 		{ "pio0",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 0) },
6110 		{ "pio1",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 1) },
6111 		{ "pio2",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 2) },
6112 		{ "pio3",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 3) },
6113 		{ "pio4",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 4) },
6114 		{ "pio5",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 5) },
6115 		{ "pio6",	.xfer_mask	= 1 << (ATA_SHIFT_PIO + 6) },
6116 		{ "mwdma0",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 0) },
6117 		{ "mwdma1",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 1) },
6118 		{ "mwdma2",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 2) },
6119 		{ "mwdma3",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 3) },
6120 		{ "mwdma4",	.xfer_mask	= 1 << (ATA_SHIFT_MWDMA + 4) },
6121 		{ "udma0",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 0) },
6122 		{ "udma16",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 0) },
6123 		{ "udma/16",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 0) },
6124 		{ "udma1",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 1) },
6125 		{ "udma25",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 1) },
6126 		{ "udma/25",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 1) },
6127 		{ "udma2",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 2) },
6128 		{ "udma33",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 2) },
6129 		{ "udma/33",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 2) },
6130 		{ "udma3",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 3) },
6131 		{ "udma44",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 3) },
6132 		{ "udma/44",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 3) },
6133 		{ "udma4",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 4) },
6134 		{ "udma66",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 4) },
6135 		{ "udma/66",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 4) },
6136 		{ "udma5",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 5) },
6137 		{ "udma100",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 5) },
6138 		{ "udma/100",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 5) },
6139 		{ "udma6",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 6) },
6140 		{ "udma133",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 6) },
6141 		{ "udma/133",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 6) },
6142 		{ "udma7",	.xfer_mask	= 1 << (ATA_SHIFT_UDMA + 7) },
6143 		{ "nohrst",	.lflags		= ATA_LFLAG_NO_HRST },
6144 		{ "nosrst",	.lflags		= ATA_LFLAG_NO_SRST },
6145 		{ "norst",	.lflags		= ATA_LFLAG_NO_HRST | ATA_LFLAG_NO_SRST },
6146 	};
6147 	char *start = *cur, *p = *cur;
6148 	char *id, *val, *endp;
6149 	const struct ata_force_param *match_fp = NULL;
6150 	int nr_matches = 0, i;
6151 
6152 	/* find where this param ends and update *cur */
6153 	while (*p != '\0' && *p != ',')
6154 		p++;
6155 
6156 	if (*p == '\0')
6157 		*cur = p;
6158 	else
6159 		*cur = p + 1;
6160 
6161 	*p = '\0';
6162 
6163 	/* parse */
6164 	p = strchr(start, ':');
6165 	if (!p) {
6166 		val = strstrip(start);
6167 		goto parse_val;
6168 	}
6169 	*p = '\0';
6170 
6171 	id = strstrip(start);
6172 	val = strstrip(p + 1);
6173 
6174 	/* parse id */
6175 	p = strchr(id, '.');
6176 	if (p) {
6177 		*p++ = '\0';
6178 		force_ent->device = simple_strtoul(p, &endp, 10);
6179 		if (p == endp || *endp != '\0') {
6180 			*reason = "invalid device";
6181 			return -EINVAL;
6182 		}
6183 	}
6184 
6185 	force_ent->port = simple_strtoul(id, &endp, 10);
6186 	if (p == endp || *endp != '\0') {
6187 		*reason = "invalid port/link";
6188 		return -EINVAL;
6189 	}
6190 
6191  parse_val:
6192 	/* parse val, allow shortcuts so that both 1.5 and 1.5Gbps work */
6193 	for (i = 0; i < ARRAY_SIZE(force_tbl); i++) {
6194 		const struct ata_force_param *fp = &force_tbl[i];
6195 
6196 		if (strncasecmp(val, fp->name, strlen(val)))
6197 			continue;
6198 
6199 		nr_matches++;
6200 		match_fp = fp;
6201 
6202 		if (strcasecmp(val, fp->name) == 0) {
6203 			nr_matches = 1;
6204 			break;
6205 		}
6206 	}
6207 
6208 	if (!nr_matches) {
6209 		*reason = "unknown value";
6210 		return -EINVAL;
6211 	}
6212 	if (nr_matches > 1) {
6213 		*reason = "ambigious value";
6214 		return -EINVAL;
6215 	}
6216 
6217 	force_ent->param = *match_fp;
6218 
6219 	return 0;
6220 }
6221 
6222 static void __init ata_parse_force_param(void)
6223 {
6224 	int idx = 0, size = 1;
6225 	int last_port = -1, last_device = -1;
6226 	char *p, *cur, *next;
6227 
6228 	/* calculate maximum number of params and allocate force_tbl */
6229 	for (p = ata_force_param_buf; *p; p++)
6230 		if (*p == ',')
6231 			size++;
6232 
6233 	ata_force_tbl = kzalloc(sizeof(ata_force_tbl[0]) * size, GFP_KERNEL);
6234 	if (!ata_force_tbl) {
6235 		printk(KERN_WARNING "ata: failed to extend force table, "
6236 		       "libata.force ignored\n");
6237 		return;
6238 	}
6239 
6240 	/* parse and populate the table */
6241 	for (cur = ata_force_param_buf; *cur != '\0'; cur = next) {
6242 		const char *reason = "";
6243 		struct ata_force_ent te = { .port = -1, .device = -1 };
6244 
6245 		next = cur;
6246 		if (ata_parse_force_one(&next, &te, &reason)) {
6247 			printk(KERN_WARNING "ata: failed to parse force "
6248 			       "parameter \"%s\" (%s)\n",
6249 			       cur, reason);
6250 			continue;
6251 		}
6252 
6253 		if (te.port == -1) {
6254 			te.port = last_port;
6255 			te.device = last_device;
6256 		}
6257 
6258 		ata_force_tbl[idx++] = te;
6259 
6260 		last_port = te.port;
6261 		last_device = te.device;
6262 	}
6263 
6264 	ata_force_tbl_size = idx;
6265 }
6266 
6267 static int __init ata_init(void)
6268 {
6269 	ata_parse_force_param();
6270 
6271 	ata_wq = create_workqueue("ata");
6272 	if (!ata_wq)
6273 		goto free_force_tbl;
6274 
6275 	ata_aux_wq = create_singlethread_workqueue("ata_aux");
6276 	if (!ata_aux_wq)
6277 		goto free_wq;
6278 
6279 	printk(KERN_DEBUG "libata version " DRV_VERSION " loaded.\n");
6280 	return 0;
6281 
6282 free_wq:
6283 	destroy_workqueue(ata_wq);
6284 free_force_tbl:
6285 	kfree(ata_force_tbl);
6286 	return -ENOMEM;
6287 }
6288 
6289 static void __exit ata_exit(void)
6290 {
6291 	kfree(ata_force_tbl);
6292 	destroy_workqueue(ata_wq);
6293 	destroy_workqueue(ata_aux_wq);
6294 }
6295 
6296 subsys_initcall(ata_init);
6297 module_exit(ata_exit);
6298 
6299 static unsigned long ratelimit_time;
6300 static DEFINE_SPINLOCK(ata_ratelimit_lock);
6301 
6302 int ata_ratelimit(void)
6303 {
6304 	int rc;
6305 	unsigned long flags;
6306 
6307 	spin_lock_irqsave(&ata_ratelimit_lock, flags);
6308 
6309 	if (time_after(jiffies, ratelimit_time)) {
6310 		rc = 1;
6311 		ratelimit_time = jiffies + (HZ/5);
6312 	} else
6313 		rc = 0;
6314 
6315 	spin_unlock_irqrestore(&ata_ratelimit_lock, flags);
6316 
6317 	return rc;
6318 }
6319 
6320 /**
6321  *	ata_wait_register - wait until register value changes
6322  *	@reg: IO-mapped register
6323  *	@mask: Mask to apply to read register value
6324  *	@val: Wait condition
6325  *	@interval: polling interval in milliseconds
6326  *	@timeout: timeout in milliseconds
6327  *
6328  *	Waiting for some bits of register to change is a common
6329  *	operation for ATA controllers.  This function reads 32bit LE
6330  *	IO-mapped register @reg and tests for the following condition.
6331  *
6332  *	(*@reg & mask) != val
6333  *
6334  *	If the condition is met, it returns; otherwise, the process is
6335  *	repeated after @interval_msec until timeout.
6336  *
6337  *	LOCKING:
6338  *	Kernel thread context (may sleep)
6339  *
6340  *	RETURNS:
6341  *	The final register value.
6342  */
6343 u32 ata_wait_register(void __iomem *reg, u32 mask, u32 val,
6344 		      unsigned long interval, unsigned long timeout)
6345 {
6346 	unsigned long deadline;
6347 	u32 tmp;
6348 
6349 	tmp = ioread32(reg);
6350 
6351 	/* Calculate timeout _after_ the first read to make sure
6352 	 * preceding writes reach the controller before starting to
6353 	 * eat away the timeout.
6354 	 */
6355 	deadline = ata_deadline(jiffies, timeout);
6356 
6357 	while ((tmp & mask) == val && time_before(jiffies, deadline)) {
6358 		msleep(interval);
6359 		tmp = ioread32(reg);
6360 	}
6361 
6362 	return tmp;
6363 }
6364 
6365 /*
6366  * Dummy port_ops
6367  */
6368 static unsigned int ata_dummy_qc_issue(struct ata_queued_cmd *qc)
6369 {
6370 	return AC_ERR_SYSTEM;
6371 }
6372 
6373 static void ata_dummy_error_handler(struct ata_port *ap)
6374 {
6375 	/* truly dummy */
6376 }
6377 
6378 struct ata_port_operations ata_dummy_port_ops = {
6379 	.qc_prep		= ata_noop_qc_prep,
6380 	.qc_issue		= ata_dummy_qc_issue,
6381 	.error_handler		= ata_dummy_error_handler,
6382 };
6383 
6384 const struct ata_port_info ata_dummy_port_info = {
6385 	.port_ops		= &ata_dummy_port_ops,
6386 };
6387 
6388 /*
6389  * libata is essentially a library of internal helper functions for
6390  * low-level ATA host controller drivers.  As such, the API/ABI is
6391  * likely to change as new drivers are added and updated.
6392  * Do not depend on ABI/API stability.
6393  */
6394 EXPORT_SYMBOL_GPL(sata_deb_timing_normal);
6395 EXPORT_SYMBOL_GPL(sata_deb_timing_hotplug);
6396 EXPORT_SYMBOL_GPL(sata_deb_timing_long);
6397 EXPORT_SYMBOL_GPL(ata_base_port_ops);
6398 EXPORT_SYMBOL_GPL(sata_port_ops);
6399 EXPORT_SYMBOL_GPL(ata_dummy_port_ops);
6400 EXPORT_SYMBOL_GPL(ata_dummy_port_info);
6401 EXPORT_SYMBOL_GPL(__ata_port_next_link);
6402 EXPORT_SYMBOL_GPL(ata_std_bios_param);
6403 EXPORT_SYMBOL_GPL(ata_host_init);
6404 EXPORT_SYMBOL_GPL(ata_host_alloc);
6405 EXPORT_SYMBOL_GPL(ata_host_alloc_pinfo);
6406 EXPORT_SYMBOL_GPL(ata_slave_link_init);
6407 EXPORT_SYMBOL_GPL(ata_host_start);
6408 EXPORT_SYMBOL_GPL(ata_host_register);
6409 EXPORT_SYMBOL_GPL(ata_host_activate);
6410 EXPORT_SYMBOL_GPL(ata_host_detach);
6411 EXPORT_SYMBOL_GPL(ata_sg_init);
6412 EXPORT_SYMBOL_GPL(ata_qc_complete);
6413 EXPORT_SYMBOL_GPL(ata_qc_complete_multiple);
6414 EXPORT_SYMBOL_GPL(atapi_cmd_type);
6415 EXPORT_SYMBOL_GPL(ata_tf_to_fis);
6416 EXPORT_SYMBOL_GPL(ata_tf_from_fis);
6417 EXPORT_SYMBOL_GPL(ata_pack_xfermask);
6418 EXPORT_SYMBOL_GPL(ata_unpack_xfermask);
6419 EXPORT_SYMBOL_GPL(ata_xfer_mask2mode);
6420 EXPORT_SYMBOL_GPL(ata_xfer_mode2mask);
6421 EXPORT_SYMBOL_GPL(ata_xfer_mode2shift);
6422 EXPORT_SYMBOL_GPL(ata_mode_string);
6423 EXPORT_SYMBOL_GPL(ata_id_xfermask);
6424 EXPORT_SYMBOL_GPL(ata_port_start);
6425 EXPORT_SYMBOL_GPL(ata_do_set_mode);
6426 EXPORT_SYMBOL_GPL(ata_std_qc_defer);
6427 EXPORT_SYMBOL_GPL(ata_noop_qc_prep);
6428 EXPORT_SYMBOL_GPL(ata_port_probe);
6429 EXPORT_SYMBOL_GPL(ata_dev_disable);
6430 EXPORT_SYMBOL_GPL(sata_set_spd);
6431 EXPORT_SYMBOL_GPL(ata_wait_after_reset);
6432 EXPORT_SYMBOL_GPL(sata_link_debounce);
6433 EXPORT_SYMBOL_GPL(sata_link_resume);
6434 EXPORT_SYMBOL_GPL(ata_std_prereset);
6435 EXPORT_SYMBOL_GPL(sata_link_hardreset);
6436 EXPORT_SYMBOL_GPL(sata_std_hardreset);
6437 EXPORT_SYMBOL_GPL(ata_std_postreset);
6438 EXPORT_SYMBOL_GPL(ata_dev_classify);
6439 EXPORT_SYMBOL_GPL(ata_dev_pair);
6440 EXPORT_SYMBOL_GPL(ata_port_disable);
6441 EXPORT_SYMBOL_GPL(ata_ratelimit);
6442 EXPORT_SYMBOL_GPL(ata_wait_register);
6443 EXPORT_SYMBOL_GPL(ata_scsi_ioctl);
6444 EXPORT_SYMBOL_GPL(ata_scsi_queuecmd);
6445 EXPORT_SYMBOL_GPL(ata_scsi_slave_config);
6446 EXPORT_SYMBOL_GPL(ata_scsi_slave_destroy);
6447 EXPORT_SYMBOL_GPL(ata_scsi_change_queue_depth);
6448 EXPORT_SYMBOL_GPL(sata_scr_valid);
6449 EXPORT_SYMBOL_GPL(sata_scr_read);
6450 EXPORT_SYMBOL_GPL(sata_scr_write);
6451 EXPORT_SYMBOL_GPL(sata_scr_write_flush);
6452 EXPORT_SYMBOL_GPL(ata_link_online);
6453 EXPORT_SYMBOL_GPL(ata_link_offline);
6454 #ifdef CONFIG_PM
6455 EXPORT_SYMBOL_GPL(ata_host_suspend);
6456 EXPORT_SYMBOL_GPL(ata_host_resume);
6457 #endif /* CONFIG_PM */
6458 EXPORT_SYMBOL_GPL(ata_id_string);
6459 EXPORT_SYMBOL_GPL(ata_id_c_string);
6460 EXPORT_SYMBOL_GPL(ata_do_dev_read_id);
6461 EXPORT_SYMBOL_GPL(ata_scsi_simulate);
6462 
6463 EXPORT_SYMBOL_GPL(ata_pio_need_iordy);
6464 EXPORT_SYMBOL_GPL(ata_timing_find_mode);
6465 EXPORT_SYMBOL_GPL(ata_timing_compute);
6466 EXPORT_SYMBOL_GPL(ata_timing_merge);
6467 EXPORT_SYMBOL_GPL(ata_timing_cycle2mode);
6468 
6469 #ifdef CONFIG_PCI
6470 EXPORT_SYMBOL_GPL(pci_test_config_bits);
6471 EXPORT_SYMBOL_GPL(ata_pci_remove_one);
6472 #ifdef CONFIG_PM
6473 EXPORT_SYMBOL_GPL(ata_pci_device_do_suspend);
6474 EXPORT_SYMBOL_GPL(ata_pci_device_do_resume);
6475 EXPORT_SYMBOL_GPL(ata_pci_device_suspend);
6476 EXPORT_SYMBOL_GPL(ata_pci_device_resume);
6477 #endif /* CONFIG_PM */
6478 #endif /* CONFIG_PCI */
6479 
6480 EXPORT_SYMBOL_GPL(__ata_ehi_push_desc);
6481 EXPORT_SYMBOL_GPL(ata_ehi_push_desc);
6482 EXPORT_SYMBOL_GPL(ata_ehi_clear_desc);
6483 EXPORT_SYMBOL_GPL(ata_port_desc);
6484 #ifdef CONFIG_PCI
6485 EXPORT_SYMBOL_GPL(ata_port_pbar_desc);
6486 #endif /* CONFIG_PCI */
6487 EXPORT_SYMBOL_GPL(ata_port_schedule_eh);
6488 EXPORT_SYMBOL_GPL(ata_link_abort);
6489 EXPORT_SYMBOL_GPL(ata_port_abort);
6490 EXPORT_SYMBOL_GPL(ata_port_freeze);
6491 EXPORT_SYMBOL_GPL(sata_async_notification);
6492 EXPORT_SYMBOL_GPL(ata_eh_freeze_port);
6493 EXPORT_SYMBOL_GPL(ata_eh_thaw_port);
6494 EXPORT_SYMBOL_GPL(ata_eh_qc_complete);
6495 EXPORT_SYMBOL_GPL(ata_eh_qc_retry);
6496 EXPORT_SYMBOL_GPL(ata_eh_analyze_ncq_error);
6497 EXPORT_SYMBOL_GPL(ata_do_eh);
6498 EXPORT_SYMBOL_GPL(ata_std_error_handler);
6499 
6500 EXPORT_SYMBOL_GPL(ata_cable_40wire);
6501 EXPORT_SYMBOL_GPL(ata_cable_80wire);
6502 EXPORT_SYMBOL_GPL(ata_cable_unknown);
6503 EXPORT_SYMBOL_GPL(ata_cable_ignore);
6504 EXPORT_SYMBOL_GPL(ata_cable_sata);
6505