xref: /linux/drivers/ata/libata-core.c (revision ed3174d93c342b8b2eeba6bbd124707d55304a7b)
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/highmem.h>
50 #include <linux/spinlock.h>
51 #include <linux/blkdev.h>
52 #include <linux/delay.h>
53 #include <linux/timer.h>
54 #include <linux/interrupt.h>
55 #include <linux/completion.h>
56 #include <linux/suspend.h>
57 #include <linux/workqueue.h>
58 #include <linux/jiffies.h>
59 #include <linux/scatterlist.h>
60 #include <linux/io.h>
61 #include <scsi/scsi.h>
62 #include <scsi/scsi_cmnd.h>
63 #include <scsi/scsi_host.h>
64 #include <linux/libata.h>
65 #include <asm/semaphore.h>
66 #include <asm/byteorder.h>
67 #include <linux/cdrom.h>
68 
69 #include "libata.h"
70 
71 
72 /* debounce timing parameters in msecs { interval, duration, timeout } */
73 const unsigned long sata_deb_timing_normal[]		= {   5,  100, 2000 };
74 const unsigned long sata_deb_timing_hotplug[]		= {  25,  500, 2000 };
75 const unsigned long sata_deb_timing_long[]		= { 100, 2000, 5000 };
76 
77 static unsigned int ata_dev_init_params(struct ata_device *dev,
78 					u16 heads, u16 sectors);
79 static unsigned int ata_dev_set_xfermode(struct ata_device *dev);
80 static unsigned int ata_dev_set_feature(struct ata_device *dev,
81 					u8 enable, u8 feature);
82 static void ata_dev_xfermask(struct ata_device *dev);
83 static unsigned long ata_dev_blacklisted(const struct ata_device *dev);
84 
85 unsigned int ata_print_id = 1;
86 static struct workqueue_struct *ata_wq;
87 
88 struct workqueue_struct *ata_aux_wq;
89 
90 int atapi_enabled = 1;
91 module_param(atapi_enabled, int, 0444);
92 MODULE_PARM_DESC(atapi_enabled, "Enable discovery of ATAPI devices (0=off, 1=on)");
93 
94 int atapi_dmadir = 0;
95 module_param(atapi_dmadir, int, 0444);
96 MODULE_PARM_DESC(atapi_dmadir, "Enable ATAPI DMADIR bridge support (0=off, 1=on)");
97 
98 int atapi_passthru16 = 1;
99 module_param(atapi_passthru16, int, 0444);
100 MODULE_PARM_DESC(atapi_passthru16, "Enable ATA_16 passthru for ATAPI devices; on by default (0=off, 1=on)");
101 
102 int libata_fua = 0;
103 module_param_named(fua, libata_fua, int, 0444);
104 MODULE_PARM_DESC(fua, "FUA support (0=off, 1=on)");
105 
106 static int ata_ignore_hpa;
107 module_param_named(ignore_hpa, ata_ignore_hpa, int, 0644);
108 MODULE_PARM_DESC(ignore_hpa, "Ignore HPA limit (0=keep BIOS limits, 1=ignore limits, using full disk)");
109 
110 static int libata_dma_mask = ATA_DMA_MASK_ATA|ATA_DMA_MASK_ATAPI|ATA_DMA_MASK_CFA;
111 module_param_named(dma, libata_dma_mask, int, 0444);
112 MODULE_PARM_DESC(dma, "DMA enable/disable (0x1==ATA, 0x2==ATAPI, 0x4==CF)");
113 
114 static int ata_probe_timeout = ATA_TMOUT_INTERNAL / HZ;
115 module_param(ata_probe_timeout, int, 0444);
116 MODULE_PARM_DESC(ata_probe_timeout, "Set ATA probing timeout (seconds)");
117 
118 int libata_noacpi = 0;
119 module_param_named(noacpi, libata_noacpi, int, 0444);
120 MODULE_PARM_DESC(noacpi, "Disables the use of ACPI in probe/suspend/resume when set");
121 
122 int libata_allow_tpm = 0;
123 module_param_named(allow_tpm, libata_allow_tpm, int, 0444);
124 MODULE_PARM_DESC(allow_tpm, "Permit the use of TPM commands");
125 
126 MODULE_AUTHOR("Jeff Garzik");
127 MODULE_DESCRIPTION("Library module for ATA devices");
128 MODULE_LICENSE("GPL");
129 MODULE_VERSION(DRV_VERSION);
130 
131 
132 /**
133  *	ata_tf_to_fis - Convert ATA taskfile to SATA FIS structure
134  *	@tf: Taskfile to convert
135  *	@pmp: Port multiplier port
136  *	@is_cmd: This FIS is for command
137  *	@fis: Buffer into which data will output
138  *
139  *	Converts a standard ATA taskfile to a Serial ATA
140  *	FIS structure (Register - Host to Device).
141  *
142  *	LOCKING:
143  *	Inherited from caller.
144  */
145 void ata_tf_to_fis(const struct ata_taskfile *tf, u8 pmp, int is_cmd, u8 *fis)
146 {
147 	fis[0] = 0x27;			/* Register - Host to Device FIS */
148 	fis[1] = pmp & 0xf;		/* Port multiplier number*/
149 	if (is_cmd)
150 		fis[1] |= (1 << 7);	/* bit 7 indicates Command FIS */
151 
152 	fis[2] = tf->command;
153 	fis[3] = tf->feature;
154 
155 	fis[4] = tf->lbal;
156 	fis[5] = tf->lbam;
157 	fis[6] = tf->lbah;
158 	fis[7] = tf->device;
159 
160 	fis[8] = tf->hob_lbal;
161 	fis[9] = tf->hob_lbam;
162 	fis[10] = tf->hob_lbah;
163 	fis[11] = tf->hob_feature;
164 
165 	fis[12] = tf->nsect;
166 	fis[13] = tf->hob_nsect;
167 	fis[14] = 0;
168 	fis[15] = tf->ctl;
169 
170 	fis[16] = 0;
171 	fis[17] = 0;
172 	fis[18] = 0;
173 	fis[19] = 0;
174 }
175 
176 /**
177  *	ata_tf_from_fis - Convert SATA FIS to ATA taskfile
178  *	@fis: Buffer from which data will be input
179  *	@tf: Taskfile to output
180  *
181  *	Converts a serial ATA FIS structure to a standard ATA taskfile.
182  *
183  *	LOCKING:
184  *	Inherited from caller.
185  */
186 
187 void ata_tf_from_fis(const u8 *fis, struct ata_taskfile *tf)
188 {
189 	tf->command	= fis[2];	/* status */
190 	tf->feature	= fis[3];	/* error */
191 
192 	tf->lbal	= fis[4];
193 	tf->lbam	= fis[5];
194 	tf->lbah	= fis[6];
195 	tf->device	= fis[7];
196 
197 	tf->hob_lbal	= fis[8];
198 	tf->hob_lbam	= fis[9];
199 	tf->hob_lbah	= fis[10];
200 
201 	tf->nsect	= fis[12];
202 	tf->hob_nsect	= fis[13];
203 }
204 
205 static const u8 ata_rw_cmds[] = {
206 	/* pio multi */
207 	ATA_CMD_READ_MULTI,
208 	ATA_CMD_WRITE_MULTI,
209 	ATA_CMD_READ_MULTI_EXT,
210 	ATA_CMD_WRITE_MULTI_EXT,
211 	0,
212 	0,
213 	0,
214 	ATA_CMD_WRITE_MULTI_FUA_EXT,
215 	/* pio */
216 	ATA_CMD_PIO_READ,
217 	ATA_CMD_PIO_WRITE,
218 	ATA_CMD_PIO_READ_EXT,
219 	ATA_CMD_PIO_WRITE_EXT,
220 	0,
221 	0,
222 	0,
223 	0,
224 	/* dma */
225 	ATA_CMD_READ,
226 	ATA_CMD_WRITE,
227 	ATA_CMD_READ_EXT,
228 	ATA_CMD_WRITE_EXT,
229 	0,
230 	0,
231 	0,
232 	ATA_CMD_WRITE_FUA_EXT
233 };
234 
235 /**
236  *	ata_rwcmd_protocol - set taskfile r/w commands and protocol
237  *	@tf: command to examine and configure
238  *	@dev: device tf belongs to
239  *
240  *	Examine the device configuration and tf->flags to calculate
241  *	the proper read/write commands and protocol to use.
242  *
243  *	LOCKING:
244  *	caller.
245  */
246 static int ata_rwcmd_protocol(struct ata_taskfile *tf, struct ata_device *dev)
247 {
248 	u8 cmd;
249 
250 	int index, fua, lba48, write;
251 
252 	fua = (tf->flags & ATA_TFLAG_FUA) ? 4 : 0;
253 	lba48 = (tf->flags & ATA_TFLAG_LBA48) ? 2 : 0;
254 	write = (tf->flags & ATA_TFLAG_WRITE) ? 1 : 0;
255 
256 	if (dev->flags & ATA_DFLAG_PIO) {
257 		tf->protocol = ATA_PROT_PIO;
258 		index = dev->multi_count ? 0 : 8;
259 	} else if (lba48 && (dev->link->ap->flags & ATA_FLAG_PIO_LBA48)) {
260 		/* Unable to use DMA due to host limitation */
261 		tf->protocol = ATA_PROT_PIO;
262 		index = dev->multi_count ? 0 : 8;
263 	} else {
264 		tf->protocol = ATA_PROT_DMA;
265 		index = 16;
266 	}
267 
268 	cmd = ata_rw_cmds[index + fua + lba48 + write];
269 	if (cmd) {
270 		tf->command = cmd;
271 		return 0;
272 	}
273 	return -1;
274 }
275 
276 /**
277  *	ata_tf_read_block - Read block address from ATA taskfile
278  *	@tf: ATA taskfile of interest
279  *	@dev: ATA device @tf belongs to
280  *
281  *	LOCKING:
282  *	None.
283  *
284  *	Read block address from @tf.  This function can handle all
285  *	three address formats - LBA, LBA48 and CHS.  tf->protocol and
286  *	flags select the address format to use.
287  *
288  *	RETURNS:
289  *	Block address read from @tf.
290  */
291 u64 ata_tf_read_block(struct ata_taskfile *tf, struct ata_device *dev)
292 {
293 	u64 block = 0;
294 
295 	if (tf->flags & ATA_TFLAG_LBA) {
296 		if (tf->flags & ATA_TFLAG_LBA48) {
297 			block |= (u64)tf->hob_lbah << 40;
298 			block |= (u64)tf->hob_lbam << 32;
299 			block |= tf->hob_lbal << 24;
300 		} else
301 			block |= (tf->device & 0xf) << 24;
302 
303 		block |= tf->lbah << 16;
304 		block |= tf->lbam << 8;
305 		block |= tf->lbal;
306 	} else {
307 		u32 cyl, head, sect;
308 
309 		cyl = tf->lbam | (tf->lbah << 8);
310 		head = tf->device & 0xf;
311 		sect = tf->lbal;
312 
313 		block = (cyl * dev->heads + head) * dev->sectors + sect;
314 	}
315 
316 	return block;
317 }
318 
319 /**
320  *	ata_build_rw_tf - Build ATA taskfile for given read/write request
321  *	@tf: Target ATA taskfile
322  *	@dev: ATA device @tf belongs to
323  *	@block: Block address
324  *	@n_block: Number of blocks
325  *	@tf_flags: RW/FUA etc...
326  *	@tag: tag
327  *
328  *	LOCKING:
329  *	None.
330  *
331  *	Build ATA taskfile @tf for read/write request described by
332  *	@block, @n_block, @tf_flags and @tag on @dev.
333  *
334  *	RETURNS:
335  *
336  *	0 on success, -ERANGE if the request is too large for @dev,
337  *	-EINVAL if the request is invalid.
338  */
339 int ata_build_rw_tf(struct ata_taskfile *tf, struct ata_device *dev,
340 		    u64 block, u32 n_block, unsigned int tf_flags,
341 		    unsigned int tag)
342 {
343 	tf->flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
344 	tf->flags |= tf_flags;
345 
346 	if (ata_ncq_enabled(dev) && likely(tag != ATA_TAG_INTERNAL)) {
347 		/* yay, NCQ */
348 		if (!lba_48_ok(block, n_block))
349 			return -ERANGE;
350 
351 		tf->protocol = ATA_PROT_NCQ;
352 		tf->flags |= ATA_TFLAG_LBA | ATA_TFLAG_LBA48;
353 
354 		if (tf->flags & ATA_TFLAG_WRITE)
355 			tf->command = ATA_CMD_FPDMA_WRITE;
356 		else
357 			tf->command = ATA_CMD_FPDMA_READ;
358 
359 		tf->nsect = tag << 3;
360 		tf->hob_feature = (n_block >> 8) & 0xff;
361 		tf->feature = n_block & 0xff;
362 
363 		tf->hob_lbah = (block >> 40) & 0xff;
364 		tf->hob_lbam = (block >> 32) & 0xff;
365 		tf->hob_lbal = (block >> 24) & 0xff;
366 		tf->lbah = (block >> 16) & 0xff;
367 		tf->lbam = (block >> 8) & 0xff;
368 		tf->lbal = block & 0xff;
369 
370 		tf->device = 1 << 6;
371 		if (tf->flags & ATA_TFLAG_FUA)
372 			tf->device |= 1 << 7;
373 	} else if (dev->flags & ATA_DFLAG_LBA) {
374 		tf->flags |= ATA_TFLAG_LBA;
375 
376 		if (lba_28_ok(block, n_block)) {
377 			/* use LBA28 */
378 			tf->device |= (block >> 24) & 0xf;
379 		} else if (lba_48_ok(block, n_block)) {
380 			if (!(dev->flags & ATA_DFLAG_LBA48))
381 				return -ERANGE;
382 
383 			/* use LBA48 */
384 			tf->flags |= ATA_TFLAG_LBA48;
385 
386 			tf->hob_nsect = (n_block >> 8) & 0xff;
387 
388 			tf->hob_lbah = (block >> 40) & 0xff;
389 			tf->hob_lbam = (block >> 32) & 0xff;
390 			tf->hob_lbal = (block >> 24) & 0xff;
391 		} else
392 			/* request too large even for LBA48 */
393 			return -ERANGE;
394 
395 		if (unlikely(ata_rwcmd_protocol(tf, dev) < 0))
396 			return -EINVAL;
397 
398 		tf->nsect = n_block & 0xff;
399 
400 		tf->lbah = (block >> 16) & 0xff;
401 		tf->lbam = (block >> 8) & 0xff;
402 		tf->lbal = block & 0xff;
403 
404 		tf->device |= ATA_LBA;
405 	} else {
406 		/* CHS */
407 		u32 sect, head, cyl, track;
408 
409 		/* The request -may- be too large for CHS addressing. */
410 		if (!lba_28_ok(block, n_block))
411 			return -ERANGE;
412 
413 		if (unlikely(ata_rwcmd_protocol(tf, dev) < 0))
414 			return -EINVAL;
415 
416 		/* Convert LBA to CHS */
417 		track = (u32)block / dev->sectors;
418 		cyl   = track / dev->heads;
419 		head  = track % dev->heads;
420 		sect  = (u32)block % dev->sectors + 1;
421 
422 		DPRINTK("block %u track %u cyl %u head %u sect %u\n",
423 			(u32)block, track, cyl, head, sect);
424 
425 		/* Check whether the converted CHS can fit.
426 		   Cylinder: 0-65535
427 		   Head: 0-15
428 		   Sector: 1-255*/
429 		if ((cyl >> 16) || (head >> 4) || (sect >> 8) || (!sect))
430 			return -ERANGE;
431 
432 		tf->nsect = n_block & 0xff; /* Sector count 0 means 256 sectors */
433 		tf->lbal = sect;
434 		tf->lbam = cyl;
435 		tf->lbah = cyl >> 8;
436 		tf->device |= head;
437 	}
438 
439 	return 0;
440 }
441 
442 /**
443  *	ata_pack_xfermask - Pack pio, mwdma and udma masks into xfer_mask
444  *	@pio_mask: pio_mask
445  *	@mwdma_mask: mwdma_mask
446  *	@udma_mask: udma_mask
447  *
448  *	Pack @pio_mask, @mwdma_mask and @udma_mask into a single
449  *	unsigned int xfer_mask.
450  *
451  *	LOCKING:
452  *	None.
453  *
454  *	RETURNS:
455  *	Packed xfer_mask.
456  */
457 unsigned long ata_pack_xfermask(unsigned long pio_mask,
458 				unsigned long mwdma_mask,
459 				unsigned long udma_mask)
460 {
461 	return ((pio_mask << ATA_SHIFT_PIO) & ATA_MASK_PIO) |
462 		((mwdma_mask << ATA_SHIFT_MWDMA) & ATA_MASK_MWDMA) |
463 		((udma_mask << ATA_SHIFT_UDMA) & ATA_MASK_UDMA);
464 }
465 
466 /**
467  *	ata_unpack_xfermask - Unpack xfer_mask into pio, mwdma and udma masks
468  *	@xfer_mask: xfer_mask to unpack
469  *	@pio_mask: resulting pio_mask
470  *	@mwdma_mask: resulting mwdma_mask
471  *	@udma_mask: resulting udma_mask
472  *
473  *	Unpack @xfer_mask into @pio_mask, @mwdma_mask and @udma_mask.
474  *	Any NULL distination masks will be ignored.
475  */
476 void ata_unpack_xfermask(unsigned long xfer_mask, unsigned long *pio_mask,
477 			 unsigned long *mwdma_mask, unsigned long *udma_mask)
478 {
479 	if (pio_mask)
480 		*pio_mask = (xfer_mask & ATA_MASK_PIO) >> ATA_SHIFT_PIO;
481 	if (mwdma_mask)
482 		*mwdma_mask = (xfer_mask & ATA_MASK_MWDMA) >> ATA_SHIFT_MWDMA;
483 	if (udma_mask)
484 		*udma_mask = (xfer_mask & ATA_MASK_UDMA) >> ATA_SHIFT_UDMA;
485 }
486 
487 static const struct ata_xfer_ent {
488 	int shift, bits;
489 	u8 base;
490 } ata_xfer_tbl[] = {
491 	{ ATA_SHIFT_PIO, ATA_NR_PIO_MODES, XFER_PIO_0 },
492 	{ ATA_SHIFT_MWDMA, ATA_NR_MWDMA_MODES, XFER_MW_DMA_0 },
493 	{ ATA_SHIFT_UDMA, ATA_NR_UDMA_MODES, XFER_UDMA_0 },
494 	{ -1, },
495 };
496 
497 /**
498  *	ata_xfer_mask2mode - Find matching XFER_* for the given xfer_mask
499  *	@xfer_mask: xfer_mask of interest
500  *
501  *	Return matching XFER_* value for @xfer_mask.  Only the highest
502  *	bit of @xfer_mask is considered.
503  *
504  *	LOCKING:
505  *	None.
506  *
507  *	RETURNS:
508  *	Matching XFER_* value, 0xff if no match found.
509  */
510 u8 ata_xfer_mask2mode(unsigned long xfer_mask)
511 {
512 	int highbit = fls(xfer_mask) - 1;
513 	const struct ata_xfer_ent *ent;
514 
515 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
516 		if (highbit >= ent->shift && highbit < ent->shift + ent->bits)
517 			return ent->base + highbit - ent->shift;
518 	return 0xff;
519 }
520 
521 /**
522  *	ata_xfer_mode2mask - Find matching xfer_mask for XFER_*
523  *	@xfer_mode: XFER_* of interest
524  *
525  *	Return matching xfer_mask for @xfer_mode.
526  *
527  *	LOCKING:
528  *	None.
529  *
530  *	RETURNS:
531  *	Matching xfer_mask, 0 if no match found.
532  */
533 unsigned long ata_xfer_mode2mask(u8 xfer_mode)
534 {
535 	const struct ata_xfer_ent *ent;
536 
537 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
538 		if (xfer_mode >= ent->base && xfer_mode < ent->base + ent->bits)
539 			return ((2 << (ent->shift + xfer_mode - ent->base)) - 1)
540 				& ~((1 << ent->shift) - 1);
541 	return 0;
542 }
543 
544 /**
545  *	ata_xfer_mode2shift - Find matching xfer_shift for XFER_*
546  *	@xfer_mode: XFER_* of interest
547  *
548  *	Return matching xfer_shift for @xfer_mode.
549  *
550  *	LOCKING:
551  *	None.
552  *
553  *	RETURNS:
554  *	Matching xfer_shift, -1 if no match found.
555  */
556 int ata_xfer_mode2shift(unsigned long xfer_mode)
557 {
558 	const struct ata_xfer_ent *ent;
559 
560 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
561 		if (xfer_mode >= ent->base && xfer_mode < ent->base + ent->bits)
562 			return ent->shift;
563 	return -1;
564 }
565 
566 /**
567  *	ata_mode_string - convert xfer_mask to string
568  *	@xfer_mask: mask of bits supported; only highest bit counts.
569  *
570  *	Determine string which represents the highest speed
571  *	(highest bit in @modemask).
572  *
573  *	LOCKING:
574  *	None.
575  *
576  *	RETURNS:
577  *	Constant C string representing highest speed listed in
578  *	@mode_mask, or the constant C string "<n/a>".
579  */
580 const char *ata_mode_string(unsigned long xfer_mask)
581 {
582 	static const char * const xfer_mode_str[] = {
583 		"PIO0",
584 		"PIO1",
585 		"PIO2",
586 		"PIO3",
587 		"PIO4",
588 		"PIO5",
589 		"PIO6",
590 		"MWDMA0",
591 		"MWDMA1",
592 		"MWDMA2",
593 		"MWDMA3",
594 		"MWDMA4",
595 		"UDMA/16",
596 		"UDMA/25",
597 		"UDMA/33",
598 		"UDMA/44",
599 		"UDMA/66",
600 		"UDMA/100",
601 		"UDMA/133",
602 		"UDMA7",
603 	};
604 	int highbit;
605 
606 	highbit = fls(xfer_mask) - 1;
607 	if (highbit >= 0 && highbit < ARRAY_SIZE(xfer_mode_str))
608 		return xfer_mode_str[highbit];
609 	return "<n/a>";
610 }
611 
612 static const char *sata_spd_string(unsigned int spd)
613 {
614 	static const char * const spd_str[] = {
615 		"1.5 Gbps",
616 		"3.0 Gbps",
617 	};
618 
619 	if (spd == 0 || (spd - 1) >= ARRAY_SIZE(spd_str))
620 		return "<unknown>";
621 	return spd_str[spd - 1];
622 }
623 
624 void ata_dev_disable(struct ata_device *dev)
625 {
626 	if (ata_dev_enabled(dev)) {
627 		if (ata_msg_drv(dev->link->ap))
628 			ata_dev_printk(dev, KERN_WARNING, "disabled\n");
629 		ata_acpi_on_disable(dev);
630 		ata_down_xfermask_limit(dev, ATA_DNXFER_FORCE_PIO0 |
631 					     ATA_DNXFER_QUIET);
632 		dev->class++;
633 	}
634 }
635 
636 static int ata_dev_set_dipm(struct ata_device *dev, enum link_pm policy)
637 {
638 	struct ata_link *link = dev->link;
639 	struct ata_port *ap = link->ap;
640 	u32 scontrol;
641 	unsigned int err_mask;
642 	int rc;
643 
644 	/*
645 	 * disallow DIPM for drivers which haven't set
646 	 * ATA_FLAG_IPM.  This is because when DIPM is enabled,
647 	 * phy ready will be set in the interrupt status on
648 	 * state changes, which will cause some drivers to
649 	 * think there are errors - additionally drivers will
650 	 * need to disable hot plug.
651 	 */
652 	if (!(ap->flags & ATA_FLAG_IPM) || !ata_dev_enabled(dev)) {
653 		ap->pm_policy = NOT_AVAILABLE;
654 		return -EINVAL;
655 	}
656 
657 	/*
658 	 * For DIPM, we will only enable it for the
659 	 * min_power setting.
660 	 *
661 	 * Why?  Because Disks are too stupid to know that
662 	 * If the host rejects a request to go to SLUMBER
663 	 * they should retry at PARTIAL, and instead it
664 	 * just would give up.  So, for medium_power to
665 	 * work at all, we need to only allow HIPM.
666 	 */
667 	rc = sata_scr_read(link, SCR_CONTROL, &scontrol);
668 	if (rc)
669 		return rc;
670 
671 	switch (policy) {
672 	case MIN_POWER:
673 		/* no restrictions on IPM transitions */
674 		scontrol &= ~(0x3 << 8);
675 		rc = sata_scr_write(link, SCR_CONTROL, scontrol);
676 		if (rc)
677 			return rc;
678 
679 		/* enable DIPM */
680 		if (dev->flags & ATA_DFLAG_DIPM)
681 			err_mask = ata_dev_set_feature(dev,
682 					SETFEATURES_SATA_ENABLE, SATA_DIPM);
683 		break;
684 	case MEDIUM_POWER:
685 		/* allow IPM to PARTIAL */
686 		scontrol &= ~(0x1 << 8);
687 		scontrol |= (0x2 << 8);
688 		rc = sata_scr_write(link, SCR_CONTROL, scontrol);
689 		if (rc)
690 			return rc;
691 
692 		/*
693 		 * we don't have to disable DIPM since IPM flags
694 		 * disallow transitions to SLUMBER, which effectively
695 		 * disable DIPM if it does not support PARTIAL
696 		 */
697 		break;
698 	case NOT_AVAILABLE:
699 	case MAX_PERFORMANCE:
700 		/* disable all IPM transitions */
701 		scontrol |= (0x3 << 8);
702 		rc = sata_scr_write(link, SCR_CONTROL, scontrol);
703 		if (rc)
704 			return rc;
705 
706 		/*
707 		 * we don't have to disable DIPM since IPM flags
708 		 * disallow all transitions which effectively
709 		 * disable DIPM anyway.
710 		 */
711 		break;
712 	}
713 
714 	/* FIXME: handle SET FEATURES failure */
715 	(void) err_mask;
716 
717 	return 0;
718 }
719 
720 /**
721  *	ata_dev_enable_pm - enable SATA interface power management
722  *	@dev:  device to enable power management
723  *	@policy: the link power management policy
724  *
725  *	Enable SATA Interface power management.  This will enable
726  *	Device Interface Power Management (DIPM) for min_power
727  * 	policy, and then call driver specific callbacks for
728  *	enabling Host Initiated Power management.
729  *
730  *	Locking: Caller.
731  *	Returns: -EINVAL if IPM is not supported, 0 otherwise.
732  */
733 void ata_dev_enable_pm(struct ata_device *dev, enum link_pm policy)
734 {
735 	int rc = 0;
736 	struct ata_port *ap = dev->link->ap;
737 
738 	/* set HIPM first, then DIPM */
739 	if (ap->ops->enable_pm)
740 		rc = ap->ops->enable_pm(ap, policy);
741 	if (rc)
742 		goto enable_pm_out;
743 	rc = ata_dev_set_dipm(dev, policy);
744 
745 enable_pm_out:
746 	if (rc)
747 		ap->pm_policy = MAX_PERFORMANCE;
748 	else
749 		ap->pm_policy = policy;
750 	return /* rc */;	/* hopefully we can use 'rc' eventually */
751 }
752 
753 #ifdef CONFIG_PM
754 /**
755  *	ata_dev_disable_pm - disable SATA interface power management
756  *	@dev: device to disable power management
757  *
758  *	Disable SATA Interface power management.  This will disable
759  *	Device Interface Power Management (DIPM) without changing
760  * 	policy,  call driver specific callbacks for disabling Host
761  * 	Initiated Power management.
762  *
763  *	Locking: Caller.
764  *	Returns: void
765  */
766 static void ata_dev_disable_pm(struct ata_device *dev)
767 {
768 	struct ata_port *ap = dev->link->ap;
769 
770 	ata_dev_set_dipm(dev, MAX_PERFORMANCE);
771 	if (ap->ops->disable_pm)
772 		ap->ops->disable_pm(ap);
773 }
774 #endif	/* CONFIG_PM */
775 
776 void ata_lpm_schedule(struct ata_port *ap, enum link_pm policy)
777 {
778 	ap->pm_policy = policy;
779 	ap->link.eh_info.action |= ATA_EHI_LPM;
780 	ap->link.eh_info.flags |= ATA_EHI_NO_AUTOPSY;
781 	ata_port_schedule_eh(ap);
782 }
783 
784 #ifdef CONFIG_PM
785 static void ata_lpm_enable(struct ata_host *host)
786 {
787 	struct ata_link *link;
788 	struct ata_port *ap;
789 	struct ata_device *dev;
790 	int i;
791 
792 	for (i = 0; i < host->n_ports; i++) {
793 		ap = host->ports[i];
794 		ata_port_for_each_link(link, ap) {
795 			ata_link_for_each_dev(dev, link)
796 				ata_dev_disable_pm(dev);
797 		}
798 	}
799 }
800 
801 static void ata_lpm_disable(struct ata_host *host)
802 {
803 	int i;
804 
805 	for (i = 0; i < host->n_ports; i++) {
806 		struct ata_port *ap = host->ports[i];
807 		ata_lpm_schedule(ap, ap->pm_policy);
808 	}
809 }
810 #endif	/* CONFIG_PM */
811 
812 
813 /**
814  *	ata_devchk - PATA device presence detection
815  *	@ap: ATA channel to examine
816  *	@device: Device to examine (starting at zero)
817  *
818  *	This technique was originally described in
819  *	Hale Landis's ATADRVR (www.ata-atapi.com), and
820  *	later found its way into the ATA/ATAPI spec.
821  *
822  *	Write a pattern to the ATA shadow registers,
823  *	and if a device is present, it will respond by
824  *	correctly storing and echoing back the
825  *	ATA shadow register contents.
826  *
827  *	LOCKING:
828  *	caller.
829  */
830 
831 static unsigned int ata_devchk(struct ata_port *ap, unsigned int device)
832 {
833 	struct ata_ioports *ioaddr = &ap->ioaddr;
834 	u8 nsect, lbal;
835 
836 	ap->ops->dev_select(ap, device);
837 
838 	iowrite8(0x55, ioaddr->nsect_addr);
839 	iowrite8(0xaa, ioaddr->lbal_addr);
840 
841 	iowrite8(0xaa, ioaddr->nsect_addr);
842 	iowrite8(0x55, ioaddr->lbal_addr);
843 
844 	iowrite8(0x55, ioaddr->nsect_addr);
845 	iowrite8(0xaa, ioaddr->lbal_addr);
846 
847 	nsect = ioread8(ioaddr->nsect_addr);
848 	lbal = ioread8(ioaddr->lbal_addr);
849 
850 	if ((nsect == 0x55) && (lbal == 0xaa))
851 		return 1;	/* we found a device */
852 
853 	return 0;		/* nothing found */
854 }
855 
856 /**
857  *	ata_dev_classify - determine device type based on ATA-spec signature
858  *	@tf: ATA taskfile register set for device to be identified
859  *
860  *	Determine from taskfile register contents whether a device is
861  *	ATA or ATAPI, as per "Signature and persistence" section
862  *	of ATA/PI spec (volume 1, sect 5.14).
863  *
864  *	LOCKING:
865  *	None.
866  *
867  *	RETURNS:
868  *	Device type, %ATA_DEV_ATA, %ATA_DEV_ATAPI, %ATA_DEV_PMP or
869  *	%ATA_DEV_UNKNOWN the event of failure.
870  */
871 unsigned int ata_dev_classify(const struct ata_taskfile *tf)
872 {
873 	/* Apple's open source Darwin code hints that some devices only
874 	 * put a proper signature into the LBA mid/high registers,
875 	 * So, we only check those.  It's sufficient for uniqueness.
876 	 *
877 	 * ATA/ATAPI-7 (d1532v1r1: Feb. 19, 2003) specified separate
878 	 * signatures for ATA and ATAPI devices attached on SerialATA,
879 	 * 0x3c/0xc3 and 0x69/0x96 respectively.  However, SerialATA
880 	 * spec has never mentioned about using different signatures
881 	 * for ATA/ATAPI devices.  Then, Serial ATA II: Port
882 	 * Multiplier specification began to use 0x69/0x96 to identify
883 	 * port multpliers and 0x3c/0xc3 to identify SEMB device.
884 	 * ATA/ATAPI-7 dropped descriptions about 0x3c/0xc3 and
885 	 * 0x69/0x96 shortly and described them as reserved for
886 	 * SerialATA.
887 	 *
888 	 * We follow the current spec and consider that 0x69/0x96
889 	 * identifies a port multiplier and 0x3c/0xc3 a SEMB device.
890 	 */
891 	if ((tf->lbam == 0) && (tf->lbah == 0)) {
892 		DPRINTK("found ATA device by sig\n");
893 		return ATA_DEV_ATA;
894 	}
895 
896 	if ((tf->lbam == 0x14) && (tf->lbah == 0xeb)) {
897 		DPRINTK("found ATAPI device by sig\n");
898 		return ATA_DEV_ATAPI;
899 	}
900 
901 	if ((tf->lbam == 0x69) && (tf->lbah == 0x96)) {
902 		DPRINTK("found PMP device by sig\n");
903 		return ATA_DEV_PMP;
904 	}
905 
906 	if ((tf->lbam == 0x3c) && (tf->lbah == 0xc3)) {
907 		printk(KERN_INFO "ata: SEMB device ignored\n");
908 		return ATA_DEV_SEMB_UNSUP; /* not yet */
909 	}
910 
911 	DPRINTK("unknown device\n");
912 	return ATA_DEV_UNKNOWN;
913 }
914 
915 /**
916  *	ata_dev_try_classify - Parse returned ATA device signature
917  *	@dev: ATA device to classify (starting at zero)
918  *	@present: device seems present
919  *	@r_err: Value of error register on completion
920  *
921  *	After an event -- SRST, E.D.D., or SATA COMRESET -- occurs,
922  *	an ATA/ATAPI-defined set of values is placed in the ATA
923  *	shadow registers, indicating the results of device detection
924  *	and diagnostics.
925  *
926  *	Select the ATA device, and read the values from the ATA shadow
927  *	registers.  Then parse according to the Error register value,
928  *	and the spec-defined values examined by ata_dev_classify().
929  *
930  *	LOCKING:
931  *	caller.
932  *
933  *	RETURNS:
934  *	Device type - %ATA_DEV_ATA, %ATA_DEV_ATAPI or %ATA_DEV_NONE.
935  */
936 unsigned int ata_dev_try_classify(struct ata_device *dev, int present,
937 				  u8 *r_err)
938 {
939 	struct ata_port *ap = dev->link->ap;
940 	struct ata_taskfile tf;
941 	unsigned int class;
942 	u8 err;
943 
944 	ap->ops->dev_select(ap, dev->devno);
945 
946 	memset(&tf, 0, sizeof(tf));
947 
948 	ap->ops->tf_read(ap, &tf);
949 	err = tf.feature;
950 	if (r_err)
951 		*r_err = err;
952 
953 	/* see if device passed diags: continue and warn later */
954 	if (err == 0)
955 		/* diagnostic fail : do nothing _YET_ */
956 		dev->horkage |= ATA_HORKAGE_DIAGNOSTIC;
957 	else if (err == 1)
958 		/* do nothing */ ;
959 	else if ((dev->devno == 0) && (err == 0x81))
960 		/* do nothing */ ;
961 	else
962 		return ATA_DEV_NONE;
963 
964 	/* determine if device is ATA or ATAPI */
965 	class = ata_dev_classify(&tf);
966 
967 	if (class == ATA_DEV_UNKNOWN) {
968 		/* If the device failed diagnostic, it's likely to
969 		 * have reported incorrect device signature too.
970 		 * Assume ATA device if the device seems present but
971 		 * device signature is invalid with diagnostic
972 		 * failure.
973 		 */
974 		if (present && (dev->horkage & ATA_HORKAGE_DIAGNOSTIC))
975 			class = ATA_DEV_ATA;
976 		else
977 			class = ATA_DEV_NONE;
978 	} else if ((class == ATA_DEV_ATA) && (ata_chk_status(ap) == 0))
979 		class = ATA_DEV_NONE;
980 
981 	return class;
982 }
983 
984 /**
985  *	ata_id_string - Convert IDENTIFY DEVICE page into string
986  *	@id: IDENTIFY DEVICE results we will examine
987  *	@s: string into which data is output
988  *	@ofs: offset into identify device page
989  *	@len: length of string to return. must be an even number.
990  *
991  *	The strings in the IDENTIFY DEVICE page are broken up into
992  *	16-bit chunks.  Run through the string, and output each
993  *	8-bit chunk linearly, regardless of platform.
994  *
995  *	LOCKING:
996  *	caller.
997  */
998 
999 void ata_id_string(const u16 *id, unsigned char *s,
1000 		   unsigned int ofs, unsigned int len)
1001 {
1002 	unsigned int c;
1003 
1004 	while (len > 0) {
1005 		c = id[ofs] >> 8;
1006 		*s = c;
1007 		s++;
1008 
1009 		c = id[ofs] & 0xff;
1010 		*s = c;
1011 		s++;
1012 
1013 		ofs++;
1014 		len -= 2;
1015 	}
1016 }
1017 
1018 /**
1019  *	ata_id_c_string - Convert IDENTIFY DEVICE page into C string
1020  *	@id: IDENTIFY DEVICE results we will examine
1021  *	@s: string into which data is output
1022  *	@ofs: offset into identify device page
1023  *	@len: length of string to return. must be an odd number.
1024  *
1025  *	This function is identical to ata_id_string except that it
1026  *	trims trailing spaces and terminates the resulting string with
1027  *	null.  @len must be actual maximum length (even number) + 1.
1028  *
1029  *	LOCKING:
1030  *	caller.
1031  */
1032 void ata_id_c_string(const u16 *id, unsigned char *s,
1033 		     unsigned int ofs, unsigned int len)
1034 {
1035 	unsigned char *p;
1036 
1037 	WARN_ON(!(len & 1));
1038 
1039 	ata_id_string(id, s, ofs, len - 1);
1040 
1041 	p = s + strnlen(s, len - 1);
1042 	while (p > s && p[-1] == ' ')
1043 		p--;
1044 	*p = '\0';
1045 }
1046 
1047 static u64 ata_id_n_sectors(const u16 *id)
1048 {
1049 	if (ata_id_has_lba(id)) {
1050 		if (ata_id_has_lba48(id))
1051 			return ata_id_u64(id, 100);
1052 		else
1053 			return ata_id_u32(id, 60);
1054 	} else {
1055 		if (ata_id_current_chs_valid(id))
1056 			return ata_id_u32(id, 57);
1057 		else
1058 			return id[1] * id[3] * id[6];
1059 	}
1060 }
1061 
1062 static u64 ata_tf_to_lba48(struct ata_taskfile *tf)
1063 {
1064 	u64 sectors = 0;
1065 
1066 	sectors |= ((u64)(tf->hob_lbah & 0xff)) << 40;
1067 	sectors |= ((u64)(tf->hob_lbam & 0xff)) << 32;
1068 	sectors |= (tf->hob_lbal & 0xff) << 24;
1069 	sectors |= (tf->lbah & 0xff) << 16;
1070 	sectors |= (tf->lbam & 0xff) << 8;
1071 	sectors |= (tf->lbal & 0xff);
1072 
1073 	return ++sectors;
1074 }
1075 
1076 static u64 ata_tf_to_lba(struct ata_taskfile *tf)
1077 {
1078 	u64 sectors = 0;
1079 
1080 	sectors |= (tf->device & 0x0f) << 24;
1081 	sectors |= (tf->lbah & 0xff) << 16;
1082 	sectors |= (tf->lbam & 0xff) << 8;
1083 	sectors |= (tf->lbal & 0xff);
1084 
1085 	return ++sectors;
1086 }
1087 
1088 /**
1089  *	ata_read_native_max_address - Read native max address
1090  *	@dev: target device
1091  *	@max_sectors: out parameter for the result native max address
1092  *
1093  *	Perform an LBA48 or LBA28 native size query upon the device in
1094  *	question.
1095  *
1096  *	RETURNS:
1097  *	0 on success, -EACCES if command is aborted by the drive.
1098  *	-EIO on other errors.
1099  */
1100 static int ata_read_native_max_address(struct ata_device *dev, u64 *max_sectors)
1101 {
1102 	unsigned int err_mask;
1103 	struct ata_taskfile tf;
1104 	int lba48 = ata_id_has_lba48(dev->id);
1105 
1106 	ata_tf_init(dev, &tf);
1107 
1108 	/* always clear all address registers */
1109 	tf.flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
1110 
1111 	if (lba48) {
1112 		tf.command = ATA_CMD_READ_NATIVE_MAX_EXT;
1113 		tf.flags |= ATA_TFLAG_LBA48;
1114 	} else
1115 		tf.command = ATA_CMD_READ_NATIVE_MAX;
1116 
1117 	tf.protocol |= ATA_PROT_NODATA;
1118 	tf.device |= ATA_LBA;
1119 
1120 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
1121 	if (err_mask) {
1122 		ata_dev_printk(dev, KERN_WARNING, "failed to read native "
1123 			       "max address (err_mask=0x%x)\n", err_mask);
1124 		if (err_mask == AC_ERR_DEV && (tf.feature & ATA_ABORTED))
1125 			return -EACCES;
1126 		return -EIO;
1127 	}
1128 
1129 	if (lba48)
1130 		*max_sectors = ata_tf_to_lba48(&tf);
1131 	else
1132 		*max_sectors = ata_tf_to_lba(&tf);
1133 	if (dev->horkage & ATA_HORKAGE_HPA_SIZE)
1134 		(*max_sectors)--;
1135 	return 0;
1136 }
1137 
1138 /**
1139  *	ata_set_max_sectors - Set max sectors
1140  *	@dev: target device
1141  *	@new_sectors: new max sectors value to set for the device
1142  *
1143  *	Set max sectors of @dev to @new_sectors.
1144  *
1145  *	RETURNS:
1146  *	0 on success, -EACCES if command is aborted or denied (due to
1147  *	previous non-volatile SET_MAX) by the drive.  -EIO on other
1148  *	errors.
1149  */
1150 static int ata_set_max_sectors(struct ata_device *dev, u64 new_sectors)
1151 {
1152 	unsigned int err_mask;
1153 	struct ata_taskfile tf;
1154 	int lba48 = ata_id_has_lba48(dev->id);
1155 
1156 	new_sectors--;
1157 
1158 	ata_tf_init(dev, &tf);
1159 
1160 	tf.flags |= ATA_TFLAG_DEVICE | ATA_TFLAG_ISADDR;
1161 
1162 	if (lba48) {
1163 		tf.command = ATA_CMD_SET_MAX_EXT;
1164 		tf.flags |= ATA_TFLAG_LBA48;
1165 
1166 		tf.hob_lbal = (new_sectors >> 24) & 0xff;
1167 		tf.hob_lbam = (new_sectors >> 32) & 0xff;
1168 		tf.hob_lbah = (new_sectors >> 40) & 0xff;
1169 	} else {
1170 		tf.command = ATA_CMD_SET_MAX;
1171 
1172 		tf.device |= (new_sectors >> 24) & 0xf;
1173 	}
1174 
1175 	tf.protocol |= ATA_PROT_NODATA;
1176 	tf.device |= ATA_LBA;
1177 
1178 	tf.lbal = (new_sectors >> 0) & 0xff;
1179 	tf.lbam = (new_sectors >> 8) & 0xff;
1180 	tf.lbah = (new_sectors >> 16) & 0xff;
1181 
1182 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
1183 	if (err_mask) {
1184 		ata_dev_printk(dev, KERN_WARNING, "failed to set "
1185 			       "max address (err_mask=0x%x)\n", err_mask);
1186 		if (err_mask == AC_ERR_DEV &&
1187 		    (tf.feature & (ATA_ABORTED | ATA_IDNF)))
1188 			return -EACCES;
1189 		return -EIO;
1190 	}
1191 
1192 	return 0;
1193 }
1194 
1195 /**
1196  *	ata_hpa_resize		-	Resize a device with an HPA set
1197  *	@dev: Device to resize
1198  *
1199  *	Read the size of an LBA28 or LBA48 disk with HPA features and resize
1200  *	it if required to the full size of the media. The caller must check
1201  *	the drive has the HPA feature set enabled.
1202  *
1203  *	RETURNS:
1204  *	0 on success, -errno on failure.
1205  */
1206 static int ata_hpa_resize(struct ata_device *dev)
1207 {
1208 	struct ata_eh_context *ehc = &dev->link->eh_context;
1209 	int print_info = ehc->i.flags & ATA_EHI_PRINTINFO;
1210 	u64 sectors = ata_id_n_sectors(dev->id);
1211 	u64 native_sectors;
1212 	int rc;
1213 
1214 	/* do we need to do it? */
1215 	if (dev->class != ATA_DEV_ATA ||
1216 	    !ata_id_has_lba(dev->id) || !ata_id_hpa_enabled(dev->id) ||
1217 	    (dev->horkage & ATA_HORKAGE_BROKEN_HPA))
1218 		return 0;
1219 
1220 	/* read native max address */
1221 	rc = ata_read_native_max_address(dev, &native_sectors);
1222 	if (rc) {
1223 		/* If HPA isn't going to be unlocked, skip HPA
1224 		 * resizing from the next try.
1225 		 */
1226 		if (!ata_ignore_hpa) {
1227 			ata_dev_printk(dev, KERN_WARNING, "HPA support seems "
1228 				       "broken, will skip HPA handling\n");
1229 			dev->horkage |= ATA_HORKAGE_BROKEN_HPA;
1230 
1231 			/* we can continue if device aborted the command */
1232 			if (rc == -EACCES)
1233 				rc = 0;
1234 		}
1235 
1236 		return rc;
1237 	}
1238 
1239 	/* nothing to do? */
1240 	if (native_sectors <= sectors || !ata_ignore_hpa) {
1241 		if (!print_info || native_sectors == sectors)
1242 			return 0;
1243 
1244 		if (native_sectors > sectors)
1245 			ata_dev_printk(dev, KERN_INFO,
1246 				"HPA detected: current %llu, native %llu\n",
1247 				(unsigned long long)sectors,
1248 				(unsigned long long)native_sectors);
1249 		else if (native_sectors < sectors)
1250 			ata_dev_printk(dev, KERN_WARNING,
1251 				"native sectors (%llu) is smaller than "
1252 				"sectors (%llu)\n",
1253 				(unsigned long long)native_sectors,
1254 				(unsigned long long)sectors);
1255 		return 0;
1256 	}
1257 
1258 	/* let's unlock HPA */
1259 	rc = ata_set_max_sectors(dev, native_sectors);
1260 	if (rc == -EACCES) {
1261 		/* if device aborted the command, skip HPA resizing */
1262 		ata_dev_printk(dev, KERN_WARNING, "device aborted resize "
1263 			       "(%llu -> %llu), skipping HPA handling\n",
1264 			       (unsigned long long)sectors,
1265 			       (unsigned long long)native_sectors);
1266 		dev->horkage |= ATA_HORKAGE_BROKEN_HPA;
1267 		return 0;
1268 	} else if (rc)
1269 		return rc;
1270 
1271 	/* re-read IDENTIFY data */
1272 	rc = ata_dev_reread_id(dev, 0);
1273 	if (rc) {
1274 		ata_dev_printk(dev, KERN_ERR, "failed to re-read IDENTIFY "
1275 			       "data after HPA resizing\n");
1276 		return rc;
1277 	}
1278 
1279 	if (print_info) {
1280 		u64 new_sectors = ata_id_n_sectors(dev->id);
1281 		ata_dev_printk(dev, KERN_INFO,
1282 			"HPA unlocked: %llu -> %llu, native %llu\n",
1283 			(unsigned long long)sectors,
1284 			(unsigned long long)new_sectors,
1285 			(unsigned long long)native_sectors);
1286 	}
1287 
1288 	return 0;
1289 }
1290 
1291 /**
1292  *	ata_noop_dev_select - Select device 0/1 on ATA bus
1293  *	@ap: ATA channel to manipulate
1294  *	@device: ATA device (numbered from zero) to select
1295  *
1296  *	This function performs no actual function.
1297  *
1298  *	May be used as the dev_select() entry in ata_port_operations.
1299  *
1300  *	LOCKING:
1301  *	caller.
1302  */
1303 void ata_noop_dev_select(struct ata_port *ap, unsigned int device)
1304 {
1305 }
1306 
1307 
1308 /**
1309  *	ata_std_dev_select - Select device 0/1 on ATA bus
1310  *	@ap: ATA channel to manipulate
1311  *	@device: ATA device (numbered from zero) to select
1312  *
1313  *	Use the method defined in the ATA specification to
1314  *	make either device 0, or device 1, active on the
1315  *	ATA channel.  Works with both PIO and MMIO.
1316  *
1317  *	May be used as the dev_select() entry in ata_port_operations.
1318  *
1319  *	LOCKING:
1320  *	caller.
1321  */
1322 
1323 void ata_std_dev_select(struct ata_port *ap, unsigned int device)
1324 {
1325 	u8 tmp;
1326 
1327 	if (device == 0)
1328 		tmp = ATA_DEVICE_OBS;
1329 	else
1330 		tmp = ATA_DEVICE_OBS | ATA_DEV1;
1331 
1332 	iowrite8(tmp, ap->ioaddr.device_addr);
1333 	ata_pause(ap);		/* needed; also flushes, for mmio */
1334 }
1335 
1336 /**
1337  *	ata_dev_select - Select device 0/1 on ATA bus
1338  *	@ap: ATA channel to manipulate
1339  *	@device: ATA device (numbered from zero) to select
1340  *	@wait: non-zero to wait for Status register BSY bit to clear
1341  *	@can_sleep: non-zero if context allows sleeping
1342  *
1343  *	Use the method defined in the ATA specification to
1344  *	make either device 0, or device 1, active on the
1345  *	ATA channel.
1346  *
1347  *	This is a high-level version of ata_std_dev_select(),
1348  *	which additionally provides the services of inserting
1349  *	the proper pauses and status polling, where needed.
1350  *
1351  *	LOCKING:
1352  *	caller.
1353  */
1354 
1355 void ata_dev_select(struct ata_port *ap, unsigned int device,
1356 			   unsigned int wait, unsigned int can_sleep)
1357 {
1358 	if (ata_msg_probe(ap))
1359 		ata_port_printk(ap, KERN_INFO, "ata_dev_select: ENTER, "
1360 				"device %u, wait %u\n", device, wait);
1361 
1362 	if (wait)
1363 		ata_wait_idle(ap);
1364 
1365 	ap->ops->dev_select(ap, device);
1366 
1367 	if (wait) {
1368 		if (can_sleep && ap->link.device[device].class == ATA_DEV_ATAPI)
1369 			msleep(150);
1370 		ata_wait_idle(ap);
1371 	}
1372 }
1373 
1374 /**
1375  *	ata_dump_id - IDENTIFY DEVICE info debugging output
1376  *	@id: IDENTIFY DEVICE page to dump
1377  *
1378  *	Dump selected 16-bit words from the given IDENTIFY DEVICE
1379  *	page.
1380  *
1381  *	LOCKING:
1382  *	caller.
1383  */
1384 
1385 static inline void ata_dump_id(const u16 *id)
1386 {
1387 	DPRINTK("49==0x%04x  "
1388 		"53==0x%04x  "
1389 		"63==0x%04x  "
1390 		"64==0x%04x  "
1391 		"75==0x%04x  \n",
1392 		id[49],
1393 		id[53],
1394 		id[63],
1395 		id[64],
1396 		id[75]);
1397 	DPRINTK("80==0x%04x  "
1398 		"81==0x%04x  "
1399 		"82==0x%04x  "
1400 		"83==0x%04x  "
1401 		"84==0x%04x  \n",
1402 		id[80],
1403 		id[81],
1404 		id[82],
1405 		id[83],
1406 		id[84]);
1407 	DPRINTK("88==0x%04x  "
1408 		"93==0x%04x\n",
1409 		id[88],
1410 		id[93]);
1411 }
1412 
1413 /**
1414  *	ata_id_xfermask - Compute xfermask from the given IDENTIFY data
1415  *	@id: IDENTIFY data to compute xfer mask from
1416  *
1417  *	Compute the xfermask for this device. This is not as trivial
1418  *	as it seems if we must consider early devices correctly.
1419  *
1420  *	FIXME: pre IDE drive timing (do we care ?).
1421  *
1422  *	LOCKING:
1423  *	None.
1424  *
1425  *	RETURNS:
1426  *	Computed xfermask
1427  */
1428 unsigned long ata_id_xfermask(const u16 *id)
1429 {
1430 	unsigned long pio_mask, mwdma_mask, udma_mask;
1431 
1432 	/* Usual case. Word 53 indicates word 64 is valid */
1433 	if (id[ATA_ID_FIELD_VALID] & (1 << 1)) {
1434 		pio_mask = id[ATA_ID_PIO_MODES] & 0x03;
1435 		pio_mask <<= 3;
1436 		pio_mask |= 0x7;
1437 	} else {
1438 		/* If word 64 isn't valid then Word 51 high byte holds
1439 		 * the PIO timing number for the maximum. Turn it into
1440 		 * a mask.
1441 		 */
1442 		u8 mode = (id[ATA_ID_OLD_PIO_MODES] >> 8) & 0xFF;
1443 		if (mode < 5)	/* Valid PIO range */
1444 			pio_mask = (2 << mode) - 1;
1445 		else
1446 			pio_mask = 1;
1447 
1448 		/* But wait.. there's more. Design your standards by
1449 		 * committee and you too can get a free iordy field to
1450 		 * process. However its the speeds not the modes that
1451 		 * are supported... Note drivers using the timing API
1452 		 * will get this right anyway
1453 		 */
1454 	}
1455 
1456 	mwdma_mask = id[ATA_ID_MWDMA_MODES] & 0x07;
1457 
1458 	if (ata_id_is_cfa(id)) {
1459 		/*
1460 		 *	Process compact flash extended modes
1461 		 */
1462 		int pio = id[163] & 0x7;
1463 		int dma = (id[163] >> 3) & 7;
1464 
1465 		if (pio)
1466 			pio_mask |= (1 << 5);
1467 		if (pio > 1)
1468 			pio_mask |= (1 << 6);
1469 		if (dma)
1470 			mwdma_mask |= (1 << 3);
1471 		if (dma > 1)
1472 			mwdma_mask |= (1 << 4);
1473 	}
1474 
1475 	udma_mask = 0;
1476 	if (id[ATA_ID_FIELD_VALID] & (1 << 2))
1477 		udma_mask = id[ATA_ID_UDMA_MODES] & 0xff;
1478 
1479 	return ata_pack_xfermask(pio_mask, mwdma_mask, udma_mask);
1480 }
1481 
1482 /**
1483  *	ata_pio_queue_task - Queue port_task
1484  *	@ap: The ata_port to queue port_task for
1485  *	@fn: workqueue function to be scheduled
1486  *	@data: data for @fn to use
1487  *	@delay: delay time for workqueue function
1488  *
1489  *	Schedule @fn(@data) for execution after @delay jiffies using
1490  *	port_task.  There is one port_task per port and it's the
1491  *	user(low level driver)'s responsibility to make sure that only
1492  *	one task is active at any given time.
1493  *
1494  *	libata core layer takes care of synchronization between
1495  *	port_task and EH.  ata_pio_queue_task() may be ignored for EH
1496  *	synchronization.
1497  *
1498  *	LOCKING:
1499  *	Inherited from caller.
1500  */
1501 static void ata_pio_queue_task(struct ata_port *ap, void *data,
1502 			       unsigned long delay)
1503 {
1504 	ap->port_task_data = data;
1505 
1506 	/* may fail if ata_port_flush_task() in progress */
1507 	queue_delayed_work(ata_wq, &ap->port_task, delay);
1508 }
1509 
1510 /**
1511  *	ata_port_flush_task - Flush port_task
1512  *	@ap: The ata_port to flush port_task for
1513  *
1514  *	After this function completes, port_task is guranteed not to
1515  *	be running or scheduled.
1516  *
1517  *	LOCKING:
1518  *	Kernel thread context (may sleep)
1519  */
1520 void ata_port_flush_task(struct ata_port *ap)
1521 {
1522 	DPRINTK("ENTER\n");
1523 
1524 	cancel_rearming_delayed_work(&ap->port_task);
1525 
1526 	if (ata_msg_ctl(ap))
1527 		ata_port_printk(ap, KERN_DEBUG, "%s: EXIT\n", __FUNCTION__);
1528 }
1529 
1530 static void ata_qc_complete_internal(struct ata_queued_cmd *qc)
1531 {
1532 	struct completion *waiting = qc->private_data;
1533 
1534 	complete(waiting);
1535 }
1536 
1537 /**
1538  *	ata_exec_internal_sg - execute libata internal command
1539  *	@dev: Device to which the command is sent
1540  *	@tf: Taskfile registers for the command and the result
1541  *	@cdb: CDB for packet command
1542  *	@dma_dir: Data tranfer direction of the command
1543  *	@sgl: sg list for the data buffer of the command
1544  *	@n_elem: Number of sg entries
1545  *	@timeout: Timeout in msecs (0 for default)
1546  *
1547  *	Executes libata internal command with timeout.  @tf contains
1548  *	command on entry and result on return.  Timeout and error
1549  *	conditions are reported via return value.  No recovery action
1550  *	is taken after a command times out.  It's caller's duty to
1551  *	clean up after timeout.
1552  *
1553  *	LOCKING:
1554  *	None.  Should be called with kernel context, might sleep.
1555  *
1556  *	RETURNS:
1557  *	Zero on success, AC_ERR_* mask on failure
1558  */
1559 unsigned ata_exec_internal_sg(struct ata_device *dev,
1560 			      struct ata_taskfile *tf, const u8 *cdb,
1561 			      int dma_dir, struct scatterlist *sgl,
1562 			      unsigned int n_elem, unsigned long timeout)
1563 {
1564 	struct ata_link *link = dev->link;
1565 	struct ata_port *ap = link->ap;
1566 	u8 command = tf->command;
1567 	struct ata_queued_cmd *qc;
1568 	unsigned int tag, preempted_tag;
1569 	u32 preempted_sactive, preempted_qc_active;
1570 	int preempted_nr_active_links;
1571 	DECLARE_COMPLETION_ONSTACK(wait);
1572 	unsigned long flags;
1573 	unsigned int err_mask;
1574 	int rc;
1575 
1576 	spin_lock_irqsave(ap->lock, flags);
1577 
1578 	/* no internal command while frozen */
1579 	if (ap->pflags & ATA_PFLAG_FROZEN) {
1580 		spin_unlock_irqrestore(ap->lock, flags);
1581 		return AC_ERR_SYSTEM;
1582 	}
1583 
1584 	/* initialize internal qc */
1585 
1586 	/* XXX: Tag 0 is used for drivers with legacy EH as some
1587 	 * drivers choke if any other tag is given.  This breaks
1588 	 * ata_tag_internal() test for those drivers.  Don't use new
1589 	 * EH stuff without converting to it.
1590 	 */
1591 	if (ap->ops->error_handler)
1592 		tag = ATA_TAG_INTERNAL;
1593 	else
1594 		tag = 0;
1595 
1596 	if (test_and_set_bit(tag, &ap->qc_allocated))
1597 		BUG();
1598 	qc = __ata_qc_from_tag(ap, tag);
1599 
1600 	qc->tag = tag;
1601 	qc->scsicmd = NULL;
1602 	qc->ap = ap;
1603 	qc->dev = dev;
1604 	ata_qc_reinit(qc);
1605 
1606 	preempted_tag = link->active_tag;
1607 	preempted_sactive = link->sactive;
1608 	preempted_qc_active = ap->qc_active;
1609 	preempted_nr_active_links = ap->nr_active_links;
1610 	link->active_tag = ATA_TAG_POISON;
1611 	link->sactive = 0;
1612 	ap->qc_active = 0;
1613 	ap->nr_active_links = 0;
1614 
1615 	/* prepare & issue qc */
1616 	qc->tf = *tf;
1617 	if (cdb)
1618 		memcpy(qc->cdb, cdb, ATAPI_CDB_LEN);
1619 	qc->flags |= ATA_QCFLAG_RESULT_TF;
1620 	qc->dma_dir = dma_dir;
1621 	if (dma_dir != DMA_NONE) {
1622 		unsigned int i, buflen = 0;
1623 		struct scatterlist *sg;
1624 
1625 		for_each_sg(sgl, sg, n_elem, i)
1626 			buflen += sg->length;
1627 
1628 		ata_sg_init(qc, sgl, n_elem);
1629 		qc->nbytes = buflen;
1630 	}
1631 
1632 	qc->private_data = &wait;
1633 	qc->complete_fn = ata_qc_complete_internal;
1634 
1635 	ata_qc_issue(qc);
1636 
1637 	spin_unlock_irqrestore(ap->lock, flags);
1638 
1639 	if (!timeout)
1640 		timeout = ata_probe_timeout * 1000 / HZ;
1641 
1642 	rc = wait_for_completion_timeout(&wait, msecs_to_jiffies(timeout));
1643 
1644 	ata_port_flush_task(ap);
1645 
1646 	if (!rc) {
1647 		spin_lock_irqsave(ap->lock, flags);
1648 
1649 		/* We're racing with irq here.  If we lose, the
1650 		 * following test prevents us from completing the qc
1651 		 * twice.  If we win, the port is frozen and will be
1652 		 * cleaned up by ->post_internal_cmd().
1653 		 */
1654 		if (qc->flags & ATA_QCFLAG_ACTIVE) {
1655 			qc->err_mask |= AC_ERR_TIMEOUT;
1656 
1657 			if (ap->ops->error_handler)
1658 				ata_port_freeze(ap);
1659 			else
1660 				ata_qc_complete(qc);
1661 
1662 			if (ata_msg_warn(ap))
1663 				ata_dev_printk(dev, KERN_WARNING,
1664 					"qc timeout (cmd 0x%x)\n", command);
1665 		}
1666 
1667 		spin_unlock_irqrestore(ap->lock, flags);
1668 	}
1669 
1670 	/* do post_internal_cmd */
1671 	if (ap->ops->post_internal_cmd)
1672 		ap->ops->post_internal_cmd(qc);
1673 
1674 	/* perform minimal error analysis */
1675 	if (qc->flags & ATA_QCFLAG_FAILED) {
1676 		if (qc->result_tf.command & (ATA_ERR | ATA_DF))
1677 			qc->err_mask |= AC_ERR_DEV;
1678 
1679 		if (!qc->err_mask)
1680 			qc->err_mask |= AC_ERR_OTHER;
1681 
1682 		if (qc->err_mask & ~AC_ERR_OTHER)
1683 			qc->err_mask &= ~AC_ERR_OTHER;
1684 	}
1685 
1686 	/* finish up */
1687 	spin_lock_irqsave(ap->lock, flags);
1688 
1689 	*tf = qc->result_tf;
1690 	err_mask = qc->err_mask;
1691 
1692 	ata_qc_free(qc);
1693 	link->active_tag = preempted_tag;
1694 	link->sactive = preempted_sactive;
1695 	ap->qc_active = preempted_qc_active;
1696 	ap->nr_active_links = preempted_nr_active_links;
1697 
1698 	/* XXX - Some LLDDs (sata_mv) disable port on command failure.
1699 	 * Until those drivers are fixed, we detect the condition
1700 	 * here, fail the command with AC_ERR_SYSTEM and reenable the
1701 	 * port.
1702 	 *
1703 	 * Note that this doesn't change any behavior as internal
1704 	 * command failure results in disabling the device in the
1705 	 * higher layer for LLDDs without new reset/EH callbacks.
1706 	 *
1707 	 * Kill the following code as soon as those drivers are fixed.
1708 	 */
1709 	if (ap->flags & ATA_FLAG_DISABLED) {
1710 		err_mask |= AC_ERR_SYSTEM;
1711 		ata_port_probe(ap);
1712 	}
1713 
1714 	spin_unlock_irqrestore(ap->lock, flags);
1715 
1716 	return err_mask;
1717 }
1718 
1719 /**
1720  *	ata_exec_internal - execute libata internal command
1721  *	@dev: Device to which the command is sent
1722  *	@tf: Taskfile registers for the command and the result
1723  *	@cdb: CDB for packet command
1724  *	@dma_dir: Data tranfer direction of the command
1725  *	@buf: Data buffer of the command
1726  *	@buflen: Length of data buffer
1727  *	@timeout: Timeout in msecs (0 for default)
1728  *
1729  *	Wrapper around ata_exec_internal_sg() which takes simple
1730  *	buffer instead of sg list.
1731  *
1732  *	LOCKING:
1733  *	None.  Should be called with kernel context, might sleep.
1734  *
1735  *	RETURNS:
1736  *	Zero on success, AC_ERR_* mask on failure
1737  */
1738 unsigned ata_exec_internal(struct ata_device *dev,
1739 			   struct ata_taskfile *tf, const u8 *cdb,
1740 			   int dma_dir, void *buf, unsigned int buflen,
1741 			   unsigned long timeout)
1742 {
1743 	struct scatterlist *psg = NULL, sg;
1744 	unsigned int n_elem = 0;
1745 
1746 	if (dma_dir != DMA_NONE) {
1747 		WARN_ON(!buf);
1748 		sg_init_one(&sg, buf, buflen);
1749 		psg = &sg;
1750 		n_elem++;
1751 	}
1752 
1753 	return ata_exec_internal_sg(dev, tf, cdb, dma_dir, psg, n_elem,
1754 				    timeout);
1755 }
1756 
1757 /**
1758  *	ata_do_simple_cmd - execute simple internal command
1759  *	@dev: Device to which the command is sent
1760  *	@cmd: Opcode to execute
1761  *
1762  *	Execute a 'simple' command, that only consists of the opcode
1763  *	'cmd' itself, without filling any other registers
1764  *
1765  *	LOCKING:
1766  *	Kernel thread context (may sleep).
1767  *
1768  *	RETURNS:
1769  *	Zero on success, AC_ERR_* mask on failure
1770  */
1771 unsigned int ata_do_simple_cmd(struct ata_device *dev, u8 cmd)
1772 {
1773 	struct ata_taskfile tf;
1774 
1775 	ata_tf_init(dev, &tf);
1776 
1777 	tf.command = cmd;
1778 	tf.flags |= ATA_TFLAG_DEVICE;
1779 	tf.protocol = ATA_PROT_NODATA;
1780 
1781 	return ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
1782 }
1783 
1784 /**
1785  *	ata_pio_need_iordy	-	check if iordy needed
1786  *	@adev: ATA device
1787  *
1788  *	Check if the current speed of the device requires IORDY. Used
1789  *	by various controllers for chip configuration.
1790  */
1791 
1792 unsigned int ata_pio_need_iordy(const struct ata_device *adev)
1793 {
1794 	/* Controller doesn't support  IORDY. Probably a pointless check
1795 	   as the caller should know this */
1796 	if (adev->link->ap->flags & ATA_FLAG_NO_IORDY)
1797 		return 0;
1798 	/* PIO3 and higher it is mandatory */
1799 	if (adev->pio_mode > XFER_PIO_2)
1800 		return 1;
1801 	/* We turn it on when possible */
1802 	if (ata_id_has_iordy(adev->id))
1803 		return 1;
1804 	return 0;
1805 }
1806 
1807 /**
1808  *	ata_pio_mask_no_iordy	-	Return the non IORDY mask
1809  *	@adev: ATA device
1810  *
1811  *	Compute the highest mode possible if we are not using iordy. Return
1812  *	-1 if no iordy mode is available.
1813  */
1814 
1815 static u32 ata_pio_mask_no_iordy(const struct ata_device *adev)
1816 {
1817 	/* If we have no drive specific rule, then PIO 2 is non IORDY */
1818 	if (adev->id[ATA_ID_FIELD_VALID] & 2) {	/* EIDE */
1819 		u16 pio = adev->id[ATA_ID_EIDE_PIO];
1820 		/* Is the speed faster than the drive allows non IORDY ? */
1821 		if (pio) {
1822 			/* This is cycle times not frequency - watch the logic! */
1823 			if (pio > 240)	/* PIO2 is 240nS per cycle */
1824 				return 3 << ATA_SHIFT_PIO;
1825 			return 7 << ATA_SHIFT_PIO;
1826 		}
1827 	}
1828 	return 3 << ATA_SHIFT_PIO;
1829 }
1830 
1831 /**
1832  *	ata_dev_read_id - Read ID data from the specified device
1833  *	@dev: target device
1834  *	@p_class: pointer to class of the target device (may be changed)
1835  *	@flags: ATA_READID_* flags
1836  *	@id: buffer to read IDENTIFY data into
1837  *
1838  *	Read ID data from the specified device.  ATA_CMD_ID_ATA is
1839  *	performed on ATA devices and ATA_CMD_ID_ATAPI on ATAPI
1840  *	devices.  This function also issues ATA_CMD_INIT_DEV_PARAMS
1841  *	for pre-ATA4 drives.
1842  *
1843  *	FIXME: ATA_CMD_ID_ATA is optional for early drives and right
1844  *	now we abort if we hit that case.
1845  *
1846  *	LOCKING:
1847  *	Kernel thread context (may sleep)
1848  *
1849  *	RETURNS:
1850  *	0 on success, -errno otherwise.
1851  */
1852 int ata_dev_read_id(struct ata_device *dev, unsigned int *p_class,
1853 		    unsigned int flags, u16 *id)
1854 {
1855 	struct ata_port *ap = dev->link->ap;
1856 	unsigned int class = *p_class;
1857 	struct ata_taskfile tf;
1858 	unsigned int err_mask = 0;
1859 	const char *reason;
1860 	int may_fallback = 1, tried_spinup = 0;
1861 	int rc;
1862 
1863 	if (ata_msg_ctl(ap))
1864 		ata_dev_printk(dev, KERN_DEBUG, "%s: ENTER\n", __FUNCTION__);
1865 
1866 	ata_dev_select(ap, dev->devno, 1, 1); /* select device 0/1 */
1867  retry:
1868 	ata_tf_init(dev, &tf);
1869 
1870 	switch (class) {
1871 	case ATA_DEV_ATA:
1872 		tf.command = ATA_CMD_ID_ATA;
1873 		break;
1874 	case ATA_DEV_ATAPI:
1875 		tf.command = ATA_CMD_ID_ATAPI;
1876 		break;
1877 	default:
1878 		rc = -ENODEV;
1879 		reason = "unsupported class";
1880 		goto err_out;
1881 	}
1882 
1883 	tf.protocol = ATA_PROT_PIO;
1884 
1885 	/* Some devices choke if TF registers contain garbage.  Make
1886 	 * sure those are properly initialized.
1887 	 */
1888 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
1889 
1890 	/* Device presence detection is unreliable on some
1891 	 * controllers.  Always poll IDENTIFY if available.
1892 	 */
1893 	tf.flags |= ATA_TFLAG_POLLING;
1894 
1895 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_FROM_DEVICE,
1896 				     id, sizeof(id[0]) * ATA_ID_WORDS, 0);
1897 	if (err_mask) {
1898 		if (err_mask & AC_ERR_NODEV_HINT) {
1899 			DPRINTK("ata%u.%d: NODEV after polling detection\n",
1900 				ap->print_id, dev->devno);
1901 			return -ENOENT;
1902 		}
1903 
1904 		/* Device or controller might have reported the wrong
1905 		 * device class.  Give a shot at the other IDENTIFY if
1906 		 * the current one is aborted by the device.
1907 		 */
1908 		if (may_fallback &&
1909 		    (err_mask == AC_ERR_DEV) && (tf.feature & ATA_ABORTED)) {
1910 			may_fallback = 0;
1911 
1912 			if (class == ATA_DEV_ATA)
1913 				class = ATA_DEV_ATAPI;
1914 			else
1915 				class = ATA_DEV_ATA;
1916 			goto retry;
1917 		}
1918 
1919 		rc = -EIO;
1920 		reason = "I/O error";
1921 		goto err_out;
1922 	}
1923 
1924 	/* Falling back doesn't make sense if ID data was read
1925 	 * successfully at least once.
1926 	 */
1927 	may_fallback = 0;
1928 
1929 	swap_buf_le16(id, ATA_ID_WORDS);
1930 
1931 	/* sanity check */
1932 	rc = -EINVAL;
1933 	reason = "device reports invalid type";
1934 
1935 	if (class == ATA_DEV_ATA) {
1936 		if (!ata_id_is_ata(id) && !ata_id_is_cfa(id))
1937 			goto err_out;
1938 	} else {
1939 		if (ata_id_is_ata(id))
1940 			goto err_out;
1941 	}
1942 
1943 	if (!tried_spinup && (id[2] == 0x37c8 || id[2] == 0x738c)) {
1944 		tried_spinup = 1;
1945 		/*
1946 		 * Drive powered-up in standby mode, and requires a specific
1947 		 * SET_FEATURES spin-up subcommand before it will accept
1948 		 * anything other than the original IDENTIFY command.
1949 		 */
1950 		err_mask = ata_dev_set_feature(dev, SETFEATURES_SPINUP, 0);
1951 		if (err_mask && id[2] != 0x738c) {
1952 			rc = -EIO;
1953 			reason = "SPINUP failed";
1954 			goto err_out;
1955 		}
1956 		/*
1957 		 * If the drive initially returned incomplete IDENTIFY info,
1958 		 * we now must reissue the IDENTIFY command.
1959 		 */
1960 		if (id[2] == 0x37c8)
1961 			goto retry;
1962 	}
1963 
1964 	if ((flags & ATA_READID_POSTRESET) && class == ATA_DEV_ATA) {
1965 		/*
1966 		 * The exact sequence expected by certain pre-ATA4 drives is:
1967 		 * SRST RESET
1968 		 * IDENTIFY (optional in early ATA)
1969 		 * INITIALIZE DEVICE PARAMETERS (later IDE and ATA)
1970 		 * anything else..
1971 		 * Some drives were very specific about that exact sequence.
1972 		 *
1973 		 * Note that ATA4 says lba is mandatory so the second check
1974 		 * shoud never trigger.
1975 		 */
1976 		if (ata_id_major_version(id) < 4 || !ata_id_has_lba(id)) {
1977 			err_mask = ata_dev_init_params(dev, id[3], id[6]);
1978 			if (err_mask) {
1979 				rc = -EIO;
1980 				reason = "INIT_DEV_PARAMS failed";
1981 				goto err_out;
1982 			}
1983 
1984 			/* current CHS translation info (id[53-58]) might be
1985 			 * changed. reread the identify device info.
1986 			 */
1987 			flags &= ~ATA_READID_POSTRESET;
1988 			goto retry;
1989 		}
1990 	}
1991 
1992 	*p_class = class;
1993 
1994 	return 0;
1995 
1996  err_out:
1997 	if (ata_msg_warn(ap))
1998 		ata_dev_printk(dev, KERN_WARNING, "failed to IDENTIFY "
1999 			       "(%s, err_mask=0x%x)\n", reason, err_mask);
2000 	return rc;
2001 }
2002 
2003 static inline u8 ata_dev_knobble(struct ata_device *dev)
2004 {
2005 	struct ata_port *ap = dev->link->ap;
2006 	return ((ap->cbl == ATA_CBL_SATA) && (!ata_id_is_sata(dev->id)));
2007 }
2008 
2009 static void ata_dev_config_ncq(struct ata_device *dev,
2010 			       char *desc, size_t desc_sz)
2011 {
2012 	struct ata_port *ap = dev->link->ap;
2013 	int hdepth = 0, ddepth = ata_id_queue_depth(dev->id);
2014 
2015 	if (!ata_id_has_ncq(dev->id)) {
2016 		desc[0] = '\0';
2017 		return;
2018 	}
2019 	if (dev->horkage & ATA_HORKAGE_NONCQ) {
2020 		snprintf(desc, desc_sz, "NCQ (not used)");
2021 		return;
2022 	}
2023 	if (ap->flags & ATA_FLAG_NCQ) {
2024 		hdepth = min(ap->scsi_host->can_queue, ATA_MAX_QUEUE - 1);
2025 		dev->flags |= ATA_DFLAG_NCQ;
2026 	}
2027 
2028 	if (hdepth >= ddepth)
2029 		snprintf(desc, desc_sz, "NCQ (depth %d)", ddepth);
2030 	else
2031 		snprintf(desc, desc_sz, "NCQ (depth %d/%d)", hdepth, ddepth);
2032 }
2033 
2034 /**
2035  *	ata_dev_configure - Configure the specified ATA/ATAPI device
2036  *	@dev: Target device to configure
2037  *
2038  *	Configure @dev according to @dev->id.  Generic and low-level
2039  *	driver specific fixups are also applied.
2040  *
2041  *	LOCKING:
2042  *	Kernel thread context (may sleep)
2043  *
2044  *	RETURNS:
2045  *	0 on success, -errno otherwise
2046  */
2047 int ata_dev_configure(struct ata_device *dev)
2048 {
2049 	struct ata_port *ap = dev->link->ap;
2050 	struct ata_eh_context *ehc = &dev->link->eh_context;
2051 	int print_info = ehc->i.flags & ATA_EHI_PRINTINFO;
2052 	const u16 *id = dev->id;
2053 	unsigned long xfer_mask;
2054 	char revbuf[7];		/* XYZ-99\0 */
2055 	char fwrevbuf[ATA_ID_FW_REV_LEN+1];
2056 	char modelbuf[ATA_ID_PROD_LEN+1];
2057 	int rc;
2058 
2059 	if (!ata_dev_enabled(dev) && ata_msg_info(ap)) {
2060 		ata_dev_printk(dev, KERN_INFO, "%s: ENTER/EXIT -- nodev\n",
2061 			       __FUNCTION__);
2062 		return 0;
2063 	}
2064 
2065 	if (ata_msg_probe(ap))
2066 		ata_dev_printk(dev, KERN_DEBUG, "%s: ENTER\n", __FUNCTION__);
2067 
2068 	/* set horkage */
2069 	dev->horkage |= ata_dev_blacklisted(dev);
2070 
2071 	/* let ACPI work its magic */
2072 	rc = ata_acpi_on_devcfg(dev);
2073 	if (rc)
2074 		return rc;
2075 
2076 	/* massage HPA, do it early as it might change IDENTIFY data */
2077 	rc = ata_hpa_resize(dev);
2078 	if (rc)
2079 		return rc;
2080 
2081 	/* print device capabilities */
2082 	if (ata_msg_probe(ap))
2083 		ata_dev_printk(dev, KERN_DEBUG,
2084 			       "%s: cfg 49:%04x 82:%04x 83:%04x 84:%04x "
2085 			       "85:%04x 86:%04x 87:%04x 88:%04x\n",
2086 			       __FUNCTION__,
2087 			       id[49], id[82], id[83], id[84],
2088 			       id[85], id[86], id[87], id[88]);
2089 
2090 	/* initialize to-be-configured parameters */
2091 	dev->flags &= ~ATA_DFLAG_CFG_MASK;
2092 	dev->max_sectors = 0;
2093 	dev->cdb_len = 0;
2094 	dev->n_sectors = 0;
2095 	dev->cylinders = 0;
2096 	dev->heads = 0;
2097 	dev->sectors = 0;
2098 
2099 	/*
2100 	 * common ATA, ATAPI feature tests
2101 	 */
2102 
2103 	/* find max transfer mode; for printk only */
2104 	xfer_mask = ata_id_xfermask(id);
2105 
2106 	if (ata_msg_probe(ap))
2107 		ata_dump_id(id);
2108 
2109 	/* SCSI only uses 4-char revisions, dump full 8 chars from ATA */
2110 	ata_id_c_string(dev->id, fwrevbuf, ATA_ID_FW_REV,
2111 			sizeof(fwrevbuf));
2112 
2113 	ata_id_c_string(dev->id, modelbuf, ATA_ID_PROD,
2114 			sizeof(modelbuf));
2115 
2116 	/* ATA-specific feature tests */
2117 	if (dev->class == ATA_DEV_ATA) {
2118 		if (ata_id_is_cfa(id)) {
2119 			if (id[162] & 1) /* CPRM may make this media unusable */
2120 				ata_dev_printk(dev, KERN_WARNING,
2121 					       "supports DRM functions and may "
2122 					       "not be fully accessable.\n");
2123 			snprintf(revbuf, 7, "CFA");
2124 		} else {
2125 			snprintf(revbuf, 7, "ATA-%d", ata_id_major_version(id));
2126 			/* Warn the user if the device has TPM extensions */
2127 			if (ata_id_has_tpm(id))
2128 				ata_dev_printk(dev, KERN_WARNING,
2129 					       "supports DRM functions and may "
2130 					       "not be fully accessable.\n");
2131 		}
2132 
2133 		dev->n_sectors = ata_id_n_sectors(id);
2134 
2135 		if (dev->id[59] & 0x100)
2136 			dev->multi_count = dev->id[59] & 0xff;
2137 
2138 		if (ata_id_has_lba(id)) {
2139 			const char *lba_desc;
2140 			char ncq_desc[20];
2141 
2142 			lba_desc = "LBA";
2143 			dev->flags |= ATA_DFLAG_LBA;
2144 			if (ata_id_has_lba48(id)) {
2145 				dev->flags |= ATA_DFLAG_LBA48;
2146 				lba_desc = "LBA48";
2147 
2148 				if (dev->n_sectors >= (1UL << 28) &&
2149 				    ata_id_has_flush_ext(id))
2150 					dev->flags |= ATA_DFLAG_FLUSH_EXT;
2151 			}
2152 
2153 			/* config NCQ */
2154 			ata_dev_config_ncq(dev, ncq_desc, sizeof(ncq_desc));
2155 
2156 			/* print device info to dmesg */
2157 			if (ata_msg_drv(ap) && print_info) {
2158 				ata_dev_printk(dev, KERN_INFO,
2159 					"%s: %s, %s, max %s\n",
2160 					revbuf, modelbuf, fwrevbuf,
2161 					ata_mode_string(xfer_mask));
2162 				ata_dev_printk(dev, KERN_INFO,
2163 					"%Lu sectors, multi %u: %s %s\n",
2164 					(unsigned long long)dev->n_sectors,
2165 					dev->multi_count, lba_desc, ncq_desc);
2166 			}
2167 		} else {
2168 			/* CHS */
2169 
2170 			/* Default translation */
2171 			dev->cylinders	= id[1];
2172 			dev->heads	= id[3];
2173 			dev->sectors	= id[6];
2174 
2175 			if (ata_id_current_chs_valid(id)) {
2176 				/* Current CHS translation is valid. */
2177 				dev->cylinders = id[54];
2178 				dev->heads     = id[55];
2179 				dev->sectors   = id[56];
2180 			}
2181 
2182 			/* print device info to dmesg */
2183 			if (ata_msg_drv(ap) && print_info) {
2184 				ata_dev_printk(dev, KERN_INFO,
2185 					"%s: %s, %s, max %s\n",
2186 					revbuf,	modelbuf, fwrevbuf,
2187 					ata_mode_string(xfer_mask));
2188 				ata_dev_printk(dev, KERN_INFO,
2189 					"%Lu sectors, multi %u, CHS %u/%u/%u\n",
2190 					(unsigned long long)dev->n_sectors,
2191 					dev->multi_count, dev->cylinders,
2192 					dev->heads, dev->sectors);
2193 			}
2194 		}
2195 
2196 		dev->cdb_len = 16;
2197 	}
2198 
2199 	/* ATAPI-specific feature tests */
2200 	else if (dev->class == ATA_DEV_ATAPI) {
2201 		const char *cdb_intr_string = "";
2202 		const char *atapi_an_string = "";
2203 		u32 sntf;
2204 
2205 		rc = atapi_cdb_len(id);
2206 		if ((rc < 12) || (rc > ATAPI_CDB_LEN)) {
2207 			if (ata_msg_warn(ap))
2208 				ata_dev_printk(dev, KERN_WARNING,
2209 					       "unsupported CDB len\n");
2210 			rc = -EINVAL;
2211 			goto err_out_nosup;
2212 		}
2213 		dev->cdb_len = (unsigned int) rc;
2214 
2215 		/* Enable ATAPI AN if both the host and device have
2216 		 * the support.  If PMP is attached, SNTF is required
2217 		 * to enable ATAPI AN to discern between PHY status
2218 		 * changed notifications and ATAPI ANs.
2219 		 */
2220 		if ((ap->flags & ATA_FLAG_AN) && ata_id_has_atapi_AN(id) &&
2221 		    (!ap->nr_pmp_links ||
2222 		     sata_scr_read(&ap->link, SCR_NOTIFICATION, &sntf) == 0)) {
2223 			unsigned int err_mask;
2224 
2225 			/* issue SET feature command to turn this on */
2226 			err_mask = ata_dev_set_feature(dev,
2227 					SETFEATURES_SATA_ENABLE, SATA_AN);
2228 			if (err_mask)
2229 				ata_dev_printk(dev, KERN_ERR,
2230 					"failed to enable ATAPI AN "
2231 					"(err_mask=0x%x)\n", err_mask);
2232 			else {
2233 				dev->flags |= ATA_DFLAG_AN;
2234 				atapi_an_string = ", ATAPI AN";
2235 			}
2236 		}
2237 
2238 		if (ata_id_cdb_intr(dev->id)) {
2239 			dev->flags |= ATA_DFLAG_CDB_INTR;
2240 			cdb_intr_string = ", CDB intr";
2241 		}
2242 
2243 		/* print device info to dmesg */
2244 		if (ata_msg_drv(ap) && print_info)
2245 			ata_dev_printk(dev, KERN_INFO,
2246 				       "ATAPI: %s, %s, max %s%s%s\n",
2247 				       modelbuf, fwrevbuf,
2248 				       ata_mode_string(xfer_mask),
2249 				       cdb_intr_string, atapi_an_string);
2250 	}
2251 
2252 	/* determine max_sectors */
2253 	dev->max_sectors = ATA_MAX_SECTORS;
2254 	if (dev->flags & ATA_DFLAG_LBA48)
2255 		dev->max_sectors = ATA_MAX_SECTORS_LBA48;
2256 
2257 	if (!(dev->horkage & ATA_HORKAGE_IPM)) {
2258 		if (ata_id_has_hipm(dev->id))
2259 			dev->flags |= ATA_DFLAG_HIPM;
2260 		if (ata_id_has_dipm(dev->id))
2261 			dev->flags |= ATA_DFLAG_DIPM;
2262 	}
2263 
2264 	/* Limit PATA drive on SATA cable bridge transfers to udma5,
2265 	   200 sectors */
2266 	if (ata_dev_knobble(dev)) {
2267 		if (ata_msg_drv(ap) && print_info)
2268 			ata_dev_printk(dev, KERN_INFO,
2269 				       "applying bridge limits\n");
2270 		dev->udma_mask &= ATA_UDMA5;
2271 		dev->max_sectors = ATA_MAX_SECTORS;
2272 	}
2273 
2274 	if ((dev->class == ATA_DEV_ATAPI) &&
2275 	    (atapi_command_packet_set(id) == TYPE_TAPE)) {
2276 		dev->max_sectors = ATA_MAX_SECTORS_TAPE;
2277 		dev->horkage |= ATA_HORKAGE_STUCK_ERR;
2278 	}
2279 
2280 	if (dev->horkage & ATA_HORKAGE_MAX_SEC_128)
2281 		dev->max_sectors = min_t(unsigned int, ATA_MAX_SECTORS_128,
2282 					 dev->max_sectors);
2283 
2284 	if (ata_dev_blacklisted(dev) & ATA_HORKAGE_IPM) {
2285 		dev->horkage |= ATA_HORKAGE_IPM;
2286 
2287 		/* reset link pm_policy for this port to no pm */
2288 		ap->pm_policy = MAX_PERFORMANCE;
2289 	}
2290 
2291 	if (ap->ops->dev_config)
2292 		ap->ops->dev_config(dev);
2293 
2294 	if (dev->horkage & ATA_HORKAGE_DIAGNOSTIC) {
2295 		/* Let the user know. We don't want to disallow opens for
2296 		   rescue purposes, or in case the vendor is just a blithering
2297 		   idiot. Do this after the dev_config call as some controllers
2298 		   with buggy firmware may want to avoid reporting false device
2299 		   bugs */
2300 
2301 		if (print_info) {
2302 			ata_dev_printk(dev, KERN_WARNING,
2303 "Drive reports diagnostics failure. This may indicate a drive\n");
2304 			ata_dev_printk(dev, KERN_WARNING,
2305 "fault or invalid emulation. Contact drive vendor for information.\n");
2306 		}
2307 	}
2308 
2309 	if (ata_msg_probe(ap))
2310 		ata_dev_printk(dev, KERN_DEBUG, "%s: EXIT, drv_stat = 0x%x\n",
2311 			__FUNCTION__, ata_chk_status(ap));
2312 	return 0;
2313 
2314 err_out_nosup:
2315 	if (ata_msg_probe(ap))
2316 		ata_dev_printk(dev, KERN_DEBUG,
2317 			       "%s: EXIT, err\n", __FUNCTION__);
2318 	return rc;
2319 }
2320 
2321 /**
2322  *	ata_cable_40wire	-	return 40 wire cable type
2323  *	@ap: port
2324  *
2325  *	Helper method for drivers which want to hardwire 40 wire cable
2326  *	detection.
2327  */
2328 
2329 int ata_cable_40wire(struct ata_port *ap)
2330 {
2331 	return ATA_CBL_PATA40;
2332 }
2333 
2334 /**
2335  *	ata_cable_80wire	-	return 80 wire cable type
2336  *	@ap: port
2337  *
2338  *	Helper method for drivers which want to hardwire 80 wire cable
2339  *	detection.
2340  */
2341 
2342 int ata_cable_80wire(struct ata_port *ap)
2343 {
2344 	return ATA_CBL_PATA80;
2345 }
2346 
2347 /**
2348  *	ata_cable_unknown	-	return unknown PATA cable.
2349  *	@ap: port
2350  *
2351  *	Helper method for drivers which have no PATA cable detection.
2352  */
2353 
2354 int ata_cable_unknown(struct ata_port *ap)
2355 {
2356 	return ATA_CBL_PATA_UNK;
2357 }
2358 
2359 /**
2360  *	ata_cable_ignore	-	return ignored PATA cable.
2361  *	@ap: port
2362  *
2363  *	Helper method for drivers which don't use cable type to limit
2364  *	transfer mode.
2365  */
2366 int ata_cable_ignore(struct ata_port *ap)
2367 {
2368 	return ATA_CBL_PATA_IGN;
2369 }
2370 
2371 /**
2372  *	ata_cable_sata	-	return SATA cable type
2373  *	@ap: port
2374  *
2375  *	Helper method for drivers which have SATA cables
2376  */
2377 
2378 int ata_cable_sata(struct ata_port *ap)
2379 {
2380 	return ATA_CBL_SATA;
2381 }
2382 
2383 /**
2384  *	ata_bus_probe - Reset and probe ATA bus
2385  *	@ap: Bus to probe
2386  *
2387  *	Master ATA bus probing function.  Initiates a hardware-dependent
2388  *	bus reset, then attempts to identify any devices found on
2389  *	the bus.
2390  *
2391  *	LOCKING:
2392  *	PCI/etc. bus probe sem.
2393  *
2394  *	RETURNS:
2395  *	Zero on success, negative errno otherwise.
2396  */
2397 
2398 int ata_bus_probe(struct ata_port *ap)
2399 {
2400 	unsigned int classes[ATA_MAX_DEVICES];
2401 	int tries[ATA_MAX_DEVICES];
2402 	int rc;
2403 	struct ata_device *dev;
2404 
2405 	ata_port_probe(ap);
2406 
2407 	ata_link_for_each_dev(dev, &ap->link)
2408 		tries[dev->devno] = ATA_PROBE_MAX_TRIES;
2409 
2410  retry:
2411 	ata_link_for_each_dev(dev, &ap->link) {
2412 		/* If we issue an SRST then an ATA drive (not ATAPI)
2413 		 * may change configuration and be in PIO0 timing. If
2414 		 * we do a hard reset (or are coming from power on)
2415 		 * this is true for ATA or ATAPI. Until we've set a
2416 		 * suitable controller mode we should not touch the
2417 		 * bus as we may be talking too fast.
2418 		 */
2419 		dev->pio_mode = XFER_PIO_0;
2420 
2421 		/* If the controller has a pio mode setup function
2422 		 * then use it to set the chipset to rights. Don't
2423 		 * touch the DMA setup as that will be dealt with when
2424 		 * configuring devices.
2425 		 */
2426 		if (ap->ops->set_piomode)
2427 			ap->ops->set_piomode(ap, dev);
2428 	}
2429 
2430 	/* reset and determine device classes */
2431 	ap->ops->phy_reset(ap);
2432 
2433 	ata_link_for_each_dev(dev, &ap->link) {
2434 		if (!(ap->flags & ATA_FLAG_DISABLED) &&
2435 		    dev->class != ATA_DEV_UNKNOWN)
2436 			classes[dev->devno] = dev->class;
2437 		else
2438 			classes[dev->devno] = ATA_DEV_NONE;
2439 
2440 		dev->class = ATA_DEV_UNKNOWN;
2441 	}
2442 
2443 	ata_port_probe(ap);
2444 
2445 	/* read IDENTIFY page and configure devices. We have to do the identify
2446 	   specific sequence bass-ackwards so that PDIAG- is released by
2447 	   the slave device */
2448 
2449 	ata_link_for_each_dev(dev, &ap->link) {
2450 		if (tries[dev->devno])
2451 			dev->class = classes[dev->devno];
2452 
2453 		if (!ata_dev_enabled(dev))
2454 			continue;
2455 
2456 		rc = ata_dev_read_id(dev, &dev->class, ATA_READID_POSTRESET,
2457 				     dev->id);
2458 		if (rc)
2459 			goto fail;
2460 	}
2461 
2462 	/* Now ask for the cable type as PDIAG- should have been released */
2463 	if (ap->ops->cable_detect)
2464 		ap->cbl = ap->ops->cable_detect(ap);
2465 
2466 	/* We may have SATA bridge glue hiding here irrespective of the
2467 	   reported cable types and sensed types */
2468 	ata_link_for_each_dev(dev, &ap->link) {
2469 		if (!ata_dev_enabled(dev))
2470 			continue;
2471 		/* SATA drives indicate we have a bridge. We don't know which
2472 		   end of the link the bridge is which is a problem */
2473 		if (ata_id_is_sata(dev->id))
2474 			ap->cbl = ATA_CBL_SATA;
2475 	}
2476 
2477 	/* After the identify sequence we can now set up the devices. We do
2478 	   this in the normal order so that the user doesn't get confused */
2479 
2480 	ata_link_for_each_dev(dev, &ap->link) {
2481 		if (!ata_dev_enabled(dev))
2482 			continue;
2483 
2484 		ap->link.eh_context.i.flags |= ATA_EHI_PRINTINFO;
2485 		rc = ata_dev_configure(dev);
2486 		ap->link.eh_context.i.flags &= ~ATA_EHI_PRINTINFO;
2487 		if (rc)
2488 			goto fail;
2489 	}
2490 
2491 	/* configure transfer mode */
2492 	rc = ata_set_mode(&ap->link, &dev);
2493 	if (rc)
2494 		goto fail;
2495 
2496 	ata_link_for_each_dev(dev, &ap->link)
2497 		if (ata_dev_enabled(dev))
2498 			return 0;
2499 
2500 	/* no device present, disable port */
2501 	ata_port_disable(ap);
2502 	return -ENODEV;
2503 
2504  fail:
2505 	tries[dev->devno]--;
2506 
2507 	switch (rc) {
2508 	case -EINVAL:
2509 		/* eeek, something went very wrong, give up */
2510 		tries[dev->devno] = 0;
2511 		break;
2512 
2513 	case -ENODEV:
2514 		/* give it just one more chance */
2515 		tries[dev->devno] = min(tries[dev->devno], 1);
2516 	case -EIO:
2517 		if (tries[dev->devno] == 1) {
2518 			/* This is the last chance, better to slow
2519 			 * down than lose it.
2520 			 */
2521 			sata_down_spd_limit(&ap->link);
2522 			ata_down_xfermask_limit(dev, ATA_DNXFER_PIO);
2523 		}
2524 	}
2525 
2526 	if (!tries[dev->devno])
2527 		ata_dev_disable(dev);
2528 
2529 	goto retry;
2530 }
2531 
2532 /**
2533  *	ata_port_probe - Mark port as enabled
2534  *	@ap: Port for which we indicate enablement
2535  *
2536  *	Modify @ap data structure such that the system
2537  *	thinks that the entire port is enabled.
2538  *
2539  *	LOCKING: host lock, or some other form of
2540  *	serialization.
2541  */
2542 
2543 void ata_port_probe(struct ata_port *ap)
2544 {
2545 	ap->flags &= ~ATA_FLAG_DISABLED;
2546 }
2547 
2548 /**
2549  *	sata_print_link_status - Print SATA link status
2550  *	@link: SATA link to printk link status about
2551  *
2552  *	This function prints link speed and status of a SATA link.
2553  *
2554  *	LOCKING:
2555  *	None.
2556  */
2557 void sata_print_link_status(struct ata_link *link)
2558 {
2559 	u32 sstatus, scontrol, tmp;
2560 
2561 	if (sata_scr_read(link, SCR_STATUS, &sstatus))
2562 		return;
2563 	sata_scr_read(link, SCR_CONTROL, &scontrol);
2564 
2565 	if (ata_link_online(link)) {
2566 		tmp = (sstatus >> 4) & 0xf;
2567 		ata_link_printk(link, KERN_INFO,
2568 				"SATA link up %s (SStatus %X SControl %X)\n",
2569 				sata_spd_string(tmp), sstatus, scontrol);
2570 	} else {
2571 		ata_link_printk(link, KERN_INFO,
2572 				"SATA link down (SStatus %X SControl %X)\n",
2573 				sstatus, scontrol);
2574 	}
2575 }
2576 
2577 /**
2578  *	ata_dev_pair		-	return other device on cable
2579  *	@adev: device
2580  *
2581  *	Obtain the other device on the same cable, or if none is
2582  *	present NULL is returned
2583  */
2584 
2585 struct ata_device *ata_dev_pair(struct ata_device *adev)
2586 {
2587 	struct ata_link *link = adev->link;
2588 	struct ata_device *pair = &link->device[1 - adev->devno];
2589 	if (!ata_dev_enabled(pair))
2590 		return NULL;
2591 	return pair;
2592 }
2593 
2594 /**
2595  *	ata_port_disable - Disable port.
2596  *	@ap: Port to be disabled.
2597  *
2598  *	Modify @ap data structure such that the system
2599  *	thinks that the entire port is disabled, and should
2600  *	never attempt to probe or communicate with devices
2601  *	on this port.
2602  *
2603  *	LOCKING: host lock, or some other form of
2604  *	serialization.
2605  */
2606 
2607 void ata_port_disable(struct ata_port *ap)
2608 {
2609 	ap->link.device[0].class = ATA_DEV_NONE;
2610 	ap->link.device[1].class = ATA_DEV_NONE;
2611 	ap->flags |= ATA_FLAG_DISABLED;
2612 }
2613 
2614 /**
2615  *	sata_down_spd_limit - adjust SATA spd limit downward
2616  *	@link: Link to adjust SATA spd limit for
2617  *
2618  *	Adjust SATA spd limit of @link downward.  Note that this
2619  *	function only adjusts the limit.  The change must be applied
2620  *	using sata_set_spd().
2621  *
2622  *	LOCKING:
2623  *	Inherited from caller.
2624  *
2625  *	RETURNS:
2626  *	0 on success, negative errno on failure
2627  */
2628 int sata_down_spd_limit(struct ata_link *link)
2629 {
2630 	u32 sstatus, spd, mask;
2631 	int rc, highbit;
2632 
2633 	if (!sata_scr_valid(link))
2634 		return -EOPNOTSUPP;
2635 
2636 	/* If SCR can be read, use it to determine the current SPD.
2637 	 * If not, use cached value in link->sata_spd.
2638 	 */
2639 	rc = sata_scr_read(link, SCR_STATUS, &sstatus);
2640 	if (rc == 0)
2641 		spd = (sstatus >> 4) & 0xf;
2642 	else
2643 		spd = link->sata_spd;
2644 
2645 	mask = link->sata_spd_limit;
2646 	if (mask <= 1)
2647 		return -EINVAL;
2648 
2649 	/* unconditionally mask off the highest bit */
2650 	highbit = fls(mask) - 1;
2651 	mask &= ~(1 << highbit);
2652 
2653 	/* Mask off all speeds higher than or equal to the current
2654 	 * one.  Force 1.5Gbps if current SPD is not available.
2655 	 */
2656 	if (spd > 1)
2657 		mask &= (1 << (spd - 1)) - 1;
2658 	else
2659 		mask &= 1;
2660 
2661 	/* were we already at the bottom? */
2662 	if (!mask)
2663 		return -EINVAL;
2664 
2665 	link->sata_spd_limit = mask;
2666 
2667 	ata_link_printk(link, KERN_WARNING, "limiting SATA link speed to %s\n",
2668 			sata_spd_string(fls(mask)));
2669 
2670 	return 0;
2671 }
2672 
2673 static int __sata_set_spd_needed(struct ata_link *link, u32 *scontrol)
2674 {
2675 	struct ata_link *host_link = &link->ap->link;
2676 	u32 limit, target, spd;
2677 
2678 	limit = link->sata_spd_limit;
2679 
2680 	/* Don't configure downstream link faster than upstream link.
2681 	 * It doesn't speed up anything and some PMPs choke on such
2682 	 * configuration.
2683 	 */
2684 	if (!ata_is_host_link(link) && host_link->sata_spd)
2685 		limit &= (1 << host_link->sata_spd) - 1;
2686 
2687 	if (limit == UINT_MAX)
2688 		target = 0;
2689 	else
2690 		target = fls(limit);
2691 
2692 	spd = (*scontrol >> 4) & 0xf;
2693 	*scontrol = (*scontrol & ~0xf0) | ((target & 0xf) << 4);
2694 
2695 	return spd != target;
2696 }
2697 
2698 /**
2699  *	sata_set_spd_needed - is SATA spd configuration needed
2700  *	@link: Link in question
2701  *
2702  *	Test whether the spd limit in SControl matches
2703  *	@link->sata_spd_limit.  This function is used to determine
2704  *	whether hardreset is necessary to apply SATA spd
2705  *	configuration.
2706  *
2707  *	LOCKING:
2708  *	Inherited from caller.
2709  *
2710  *	RETURNS:
2711  *	1 if SATA spd configuration is needed, 0 otherwise.
2712  */
2713 int sata_set_spd_needed(struct ata_link *link)
2714 {
2715 	u32 scontrol;
2716 
2717 	if (sata_scr_read(link, SCR_CONTROL, &scontrol))
2718 		return 1;
2719 
2720 	return __sata_set_spd_needed(link, &scontrol);
2721 }
2722 
2723 /**
2724  *	sata_set_spd - set SATA spd according to spd limit
2725  *	@link: Link to set SATA spd for
2726  *
2727  *	Set SATA spd of @link according to sata_spd_limit.
2728  *
2729  *	LOCKING:
2730  *	Inherited from caller.
2731  *
2732  *	RETURNS:
2733  *	0 if spd doesn't need to be changed, 1 if spd has been
2734  *	changed.  Negative errno if SCR registers are inaccessible.
2735  */
2736 int sata_set_spd(struct ata_link *link)
2737 {
2738 	u32 scontrol;
2739 	int rc;
2740 
2741 	if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
2742 		return rc;
2743 
2744 	if (!__sata_set_spd_needed(link, &scontrol))
2745 		return 0;
2746 
2747 	if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
2748 		return rc;
2749 
2750 	return 1;
2751 }
2752 
2753 /*
2754  * This mode timing computation functionality is ported over from
2755  * drivers/ide/ide-timing.h and was originally written by Vojtech Pavlik
2756  */
2757 /*
2758  * PIO 0-4, MWDMA 0-2 and UDMA 0-6 timings (in nanoseconds).
2759  * These were taken from ATA/ATAPI-6 standard, rev 0a, except
2760  * for UDMA6, which is currently supported only by Maxtor drives.
2761  *
2762  * For PIO 5/6 MWDMA 3/4 see the CFA specification 3.0.
2763  */
2764 
2765 static const struct ata_timing ata_timing[] = {
2766 /*	{ XFER_PIO_SLOW, 120, 290, 240, 960, 290, 240, 960,   0 }, */
2767 	{ XFER_PIO_0,     70, 290, 240, 600, 165, 150, 600,   0 },
2768 	{ XFER_PIO_1,     50, 290,  93, 383, 125, 100, 383,   0 },
2769 	{ XFER_PIO_2,     30, 290,  40, 330, 100,  90, 240,   0 },
2770 	{ XFER_PIO_3,     30,  80,  70, 180,  80,  70, 180,   0 },
2771 	{ XFER_PIO_4,     25,  70,  25, 120,  70,  25, 120,   0 },
2772 	{ XFER_PIO_5,     15,  65,  25, 100,  65,  25, 100,   0 },
2773 	{ XFER_PIO_6,     10,  55,  20,  80,  55,  20,  80,   0 },
2774 
2775 	{ XFER_SW_DMA_0, 120,   0,   0,   0, 480, 480, 960,   0 },
2776 	{ XFER_SW_DMA_1,  90,   0,   0,   0, 240, 240, 480,   0 },
2777 	{ XFER_SW_DMA_2,  60,   0,   0,   0, 120, 120, 240,   0 },
2778 
2779 	{ XFER_MW_DMA_0,  60,   0,   0,   0, 215, 215, 480,   0 },
2780 	{ XFER_MW_DMA_1,  45,   0,   0,   0,  80,  50, 150,   0 },
2781 	{ XFER_MW_DMA_2,  25,   0,   0,   0,  70,  25, 120,   0 },
2782 	{ XFER_MW_DMA_3,  25,   0,   0,   0,  65,  25, 100,   0 },
2783 	{ XFER_MW_DMA_4,  25,   0,   0,   0,  55,  20,  80,   0 },
2784 
2785 /*	{ XFER_UDMA_SLOW,  0,   0,   0,   0,   0,   0,   0, 150 }, */
2786 	{ XFER_UDMA_0,     0,   0,   0,   0,   0,   0,   0, 120 },
2787 	{ XFER_UDMA_1,     0,   0,   0,   0,   0,   0,   0,  80 },
2788 	{ XFER_UDMA_2,     0,   0,   0,   0,   0,   0,   0,  60 },
2789 	{ XFER_UDMA_3,     0,   0,   0,   0,   0,   0,   0,  45 },
2790 	{ XFER_UDMA_4,     0,   0,   0,   0,   0,   0,   0,  30 },
2791 	{ XFER_UDMA_5,     0,   0,   0,   0,   0,   0,   0,  20 },
2792 	{ XFER_UDMA_6,     0,   0,   0,   0,   0,   0,   0,  15 },
2793 
2794 	{ 0xFF }
2795 };
2796 
2797 #define ENOUGH(v, unit)		(((v)-1)/(unit)+1)
2798 #define EZ(v, unit)		((v)?ENOUGH(v, unit):0)
2799 
2800 static void ata_timing_quantize(const struct ata_timing *t, struct ata_timing *q, int T, int UT)
2801 {
2802 	q->setup   = EZ(t->setup   * 1000,  T);
2803 	q->act8b   = EZ(t->act8b   * 1000,  T);
2804 	q->rec8b   = EZ(t->rec8b   * 1000,  T);
2805 	q->cyc8b   = EZ(t->cyc8b   * 1000,  T);
2806 	q->active  = EZ(t->active  * 1000,  T);
2807 	q->recover = EZ(t->recover * 1000,  T);
2808 	q->cycle   = EZ(t->cycle   * 1000,  T);
2809 	q->udma    = EZ(t->udma    * 1000, UT);
2810 }
2811 
2812 void ata_timing_merge(const struct ata_timing *a, const struct ata_timing *b,
2813 		      struct ata_timing *m, unsigned int what)
2814 {
2815 	if (what & ATA_TIMING_SETUP  ) m->setup   = max(a->setup,   b->setup);
2816 	if (what & ATA_TIMING_ACT8B  ) m->act8b   = max(a->act8b,   b->act8b);
2817 	if (what & ATA_TIMING_REC8B  ) m->rec8b   = max(a->rec8b,   b->rec8b);
2818 	if (what & ATA_TIMING_CYC8B  ) m->cyc8b   = max(a->cyc8b,   b->cyc8b);
2819 	if (what & ATA_TIMING_ACTIVE ) m->active  = max(a->active,  b->active);
2820 	if (what & ATA_TIMING_RECOVER) m->recover = max(a->recover, b->recover);
2821 	if (what & ATA_TIMING_CYCLE  ) m->cycle   = max(a->cycle,   b->cycle);
2822 	if (what & ATA_TIMING_UDMA   ) m->udma    = max(a->udma,    b->udma);
2823 }
2824 
2825 const struct ata_timing *ata_timing_find_mode(u8 xfer_mode)
2826 {
2827 	const struct ata_timing *t = ata_timing;
2828 
2829 	while (xfer_mode > t->mode)
2830 		t++;
2831 
2832 	if (xfer_mode == t->mode)
2833 		return t;
2834 	return NULL;
2835 }
2836 
2837 int ata_timing_compute(struct ata_device *adev, unsigned short speed,
2838 		       struct ata_timing *t, int T, int UT)
2839 {
2840 	const struct ata_timing *s;
2841 	struct ata_timing p;
2842 
2843 	/*
2844 	 * Find the mode.
2845 	 */
2846 
2847 	if (!(s = ata_timing_find_mode(speed)))
2848 		return -EINVAL;
2849 
2850 	memcpy(t, s, sizeof(*s));
2851 
2852 	/*
2853 	 * If the drive is an EIDE drive, it can tell us it needs extended
2854 	 * PIO/MW_DMA cycle timing.
2855 	 */
2856 
2857 	if (adev->id[ATA_ID_FIELD_VALID] & 2) {	/* EIDE drive */
2858 		memset(&p, 0, sizeof(p));
2859 		if (speed >= XFER_PIO_0 && speed <= XFER_SW_DMA_0) {
2860 			if (speed <= XFER_PIO_2) p.cycle = p.cyc8b = adev->id[ATA_ID_EIDE_PIO];
2861 					    else p.cycle = p.cyc8b = adev->id[ATA_ID_EIDE_PIO_IORDY];
2862 		} else if (speed >= XFER_MW_DMA_0 && speed <= XFER_MW_DMA_2) {
2863 			p.cycle = adev->id[ATA_ID_EIDE_DMA_MIN];
2864 		}
2865 		ata_timing_merge(&p, t, t, ATA_TIMING_CYCLE | ATA_TIMING_CYC8B);
2866 	}
2867 
2868 	/*
2869 	 * Convert the timing to bus clock counts.
2870 	 */
2871 
2872 	ata_timing_quantize(t, t, T, UT);
2873 
2874 	/*
2875 	 * Even in DMA/UDMA modes we still use PIO access for IDENTIFY,
2876 	 * S.M.A.R.T * and some other commands. We have to ensure that the
2877 	 * DMA cycle timing is slower/equal than the fastest PIO timing.
2878 	 */
2879 
2880 	if (speed > XFER_PIO_6) {
2881 		ata_timing_compute(adev, adev->pio_mode, &p, T, UT);
2882 		ata_timing_merge(&p, t, t, ATA_TIMING_ALL);
2883 	}
2884 
2885 	/*
2886 	 * Lengthen active & recovery time so that cycle time is correct.
2887 	 */
2888 
2889 	if (t->act8b + t->rec8b < t->cyc8b) {
2890 		t->act8b += (t->cyc8b - (t->act8b + t->rec8b)) / 2;
2891 		t->rec8b = t->cyc8b - t->act8b;
2892 	}
2893 
2894 	if (t->active + t->recover < t->cycle) {
2895 		t->active += (t->cycle - (t->active + t->recover)) / 2;
2896 		t->recover = t->cycle - t->active;
2897 	}
2898 
2899 	/* In a few cases quantisation may produce enough errors to
2900 	   leave t->cycle too low for the sum of active and recovery
2901 	   if so we must correct this */
2902 	if (t->active + t->recover > t->cycle)
2903 		t->cycle = t->active + t->recover;
2904 
2905 	return 0;
2906 }
2907 
2908 /**
2909  *	ata_timing_cycle2mode - find xfer mode for the specified cycle duration
2910  *	@xfer_shift: ATA_SHIFT_* value for transfer type to examine.
2911  *	@cycle: cycle duration in ns
2912  *
2913  *	Return matching xfer mode for @cycle.  The returned mode is of
2914  *	the transfer type specified by @xfer_shift.  If @cycle is too
2915  *	slow for @xfer_shift, 0xff is returned.  If @cycle is faster
2916  *	than the fastest known mode, the fasted mode is returned.
2917  *
2918  *	LOCKING:
2919  *	None.
2920  *
2921  *	RETURNS:
2922  *	Matching xfer_mode, 0xff if no match found.
2923  */
2924 u8 ata_timing_cycle2mode(unsigned int xfer_shift, int cycle)
2925 {
2926 	u8 base_mode = 0xff, last_mode = 0xff;
2927 	const struct ata_xfer_ent *ent;
2928 	const struct ata_timing *t;
2929 
2930 	for (ent = ata_xfer_tbl; ent->shift >= 0; ent++)
2931 		if (ent->shift == xfer_shift)
2932 			base_mode = ent->base;
2933 
2934 	for (t = ata_timing_find_mode(base_mode);
2935 	     t && ata_xfer_mode2shift(t->mode) == xfer_shift; t++) {
2936 		unsigned short this_cycle;
2937 
2938 		switch (xfer_shift) {
2939 		case ATA_SHIFT_PIO:
2940 		case ATA_SHIFT_MWDMA:
2941 			this_cycle = t->cycle;
2942 			break;
2943 		case ATA_SHIFT_UDMA:
2944 			this_cycle = t->udma;
2945 			break;
2946 		default:
2947 			return 0xff;
2948 		}
2949 
2950 		if (cycle > this_cycle)
2951 			break;
2952 
2953 		last_mode = t->mode;
2954 	}
2955 
2956 	return last_mode;
2957 }
2958 
2959 /**
2960  *	ata_down_xfermask_limit - adjust dev xfer masks downward
2961  *	@dev: Device to adjust xfer masks
2962  *	@sel: ATA_DNXFER_* selector
2963  *
2964  *	Adjust xfer masks of @dev downward.  Note that this function
2965  *	does not apply the change.  Invoking ata_set_mode() afterwards
2966  *	will apply the limit.
2967  *
2968  *	LOCKING:
2969  *	Inherited from caller.
2970  *
2971  *	RETURNS:
2972  *	0 on success, negative errno on failure
2973  */
2974 int ata_down_xfermask_limit(struct ata_device *dev, unsigned int sel)
2975 {
2976 	char buf[32];
2977 	unsigned long orig_mask, xfer_mask;
2978 	unsigned long pio_mask, mwdma_mask, udma_mask;
2979 	int quiet, highbit;
2980 
2981 	quiet = !!(sel & ATA_DNXFER_QUIET);
2982 	sel &= ~ATA_DNXFER_QUIET;
2983 
2984 	xfer_mask = orig_mask = ata_pack_xfermask(dev->pio_mask,
2985 						  dev->mwdma_mask,
2986 						  dev->udma_mask);
2987 	ata_unpack_xfermask(xfer_mask, &pio_mask, &mwdma_mask, &udma_mask);
2988 
2989 	switch (sel) {
2990 	case ATA_DNXFER_PIO:
2991 		highbit = fls(pio_mask) - 1;
2992 		pio_mask &= ~(1 << highbit);
2993 		break;
2994 
2995 	case ATA_DNXFER_DMA:
2996 		if (udma_mask) {
2997 			highbit = fls(udma_mask) - 1;
2998 			udma_mask &= ~(1 << highbit);
2999 			if (!udma_mask)
3000 				return -ENOENT;
3001 		} else if (mwdma_mask) {
3002 			highbit = fls(mwdma_mask) - 1;
3003 			mwdma_mask &= ~(1 << highbit);
3004 			if (!mwdma_mask)
3005 				return -ENOENT;
3006 		}
3007 		break;
3008 
3009 	case ATA_DNXFER_40C:
3010 		udma_mask &= ATA_UDMA_MASK_40C;
3011 		break;
3012 
3013 	case ATA_DNXFER_FORCE_PIO0:
3014 		pio_mask &= 1;
3015 	case ATA_DNXFER_FORCE_PIO:
3016 		mwdma_mask = 0;
3017 		udma_mask = 0;
3018 		break;
3019 
3020 	default:
3021 		BUG();
3022 	}
3023 
3024 	xfer_mask &= ata_pack_xfermask(pio_mask, mwdma_mask, udma_mask);
3025 
3026 	if (!(xfer_mask & ATA_MASK_PIO) || xfer_mask == orig_mask)
3027 		return -ENOENT;
3028 
3029 	if (!quiet) {
3030 		if (xfer_mask & (ATA_MASK_MWDMA | ATA_MASK_UDMA))
3031 			snprintf(buf, sizeof(buf), "%s:%s",
3032 				 ata_mode_string(xfer_mask),
3033 				 ata_mode_string(xfer_mask & ATA_MASK_PIO));
3034 		else
3035 			snprintf(buf, sizeof(buf), "%s",
3036 				 ata_mode_string(xfer_mask));
3037 
3038 		ata_dev_printk(dev, KERN_WARNING,
3039 			       "limiting speed to %s\n", buf);
3040 	}
3041 
3042 	ata_unpack_xfermask(xfer_mask, &dev->pio_mask, &dev->mwdma_mask,
3043 			    &dev->udma_mask);
3044 
3045 	return 0;
3046 }
3047 
3048 static int ata_dev_set_mode(struct ata_device *dev)
3049 {
3050 	struct ata_eh_context *ehc = &dev->link->eh_context;
3051 	const char *dev_err_whine = "";
3052 	int ign_dev_err = 0;
3053 	unsigned int err_mask;
3054 	int rc;
3055 
3056 	dev->flags &= ~ATA_DFLAG_PIO;
3057 	if (dev->xfer_shift == ATA_SHIFT_PIO)
3058 		dev->flags |= ATA_DFLAG_PIO;
3059 
3060 	err_mask = ata_dev_set_xfermode(dev);
3061 
3062 	if (err_mask & ~AC_ERR_DEV)
3063 		goto fail;
3064 
3065 	/* revalidate */
3066 	ehc->i.flags |= ATA_EHI_POST_SETMODE;
3067 	rc = ata_dev_revalidate(dev, ATA_DEV_UNKNOWN, 0);
3068 	ehc->i.flags &= ~ATA_EHI_POST_SETMODE;
3069 	if (rc)
3070 		return rc;
3071 
3072 	/* Old CFA may refuse this command, which is just fine */
3073 	if (dev->xfer_shift == ATA_SHIFT_PIO && ata_id_is_cfa(dev->id))
3074 		ign_dev_err = 1;
3075 
3076 	/* Some very old devices and some bad newer ones fail any kind of
3077 	   SET_XFERMODE request but support PIO0-2 timings and no IORDY */
3078 	if (dev->xfer_shift == ATA_SHIFT_PIO && !ata_id_has_iordy(dev->id) &&
3079 			dev->pio_mode <= XFER_PIO_2)
3080 		ign_dev_err = 1;
3081 
3082 	/* Early MWDMA devices do DMA but don't allow DMA mode setting.
3083 	   Don't fail an MWDMA0 set IFF the device indicates it is in MWDMA0 */
3084 	if (dev->xfer_shift == ATA_SHIFT_MWDMA &&
3085 	    dev->dma_mode == XFER_MW_DMA_0 &&
3086 	    (dev->id[63] >> 8) & 1)
3087 		ign_dev_err = 1;
3088 
3089 	/* if the device is actually configured correctly, ignore dev err */
3090 	if (dev->xfer_mode == ata_xfer_mask2mode(ata_id_xfermask(dev->id)))
3091 		ign_dev_err = 1;
3092 
3093 	if (err_mask & AC_ERR_DEV) {
3094 		if (!ign_dev_err)
3095 			goto fail;
3096 		else
3097 			dev_err_whine = " (device error ignored)";
3098 	}
3099 
3100 	DPRINTK("xfer_shift=%u, xfer_mode=0x%x\n",
3101 		dev->xfer_shift, (int)dev->xfer_mode);
3102 
3103 	ata_dev_printk(dev, KERN_INFO, "configured for %s%s\n",
3104 		       ata_mode_string(ata_xfer_mode2mask(dev->xfer_mode)),
3105 		       dev_err_whine);
3106 
3107 	return 0;
3108 
3109  fail:
3110 	ata_dev_printk(dev, KERN_ERR, "failed to set xfermode "
3111 		       "(err_mask=0x%x)\n", err_mask);
3112 	return -EIO;
3113 }
3114 
3115 /**
3116  *	ata_do_set_mode - Program timings and issue SET FEATURES - XFER
3117  *	@link: link on which timings will be programmed
3118  *	@r_failed_dev: out parameter for failed device
3119  *
3120  *	Standard implementation of the function used to tune and set
3121  *	ATA device disk transfer mode (PIO3, UDMA6, etc.).  If
3122  *	ata_dev_set_mode() fails, pointer to the failing device is
3123  *	returned in @r_failed_dev.
3124  *
3125  *	LOCKING:
3126  *	PCI/etc. bus probe sem.
3127  *
3128  *	RETURNS:
3129  *	0 on success, negative errno otherwise
3130  */
3131 
3132 int ata_do_set_mode(struct ata_link *link, struct ata_device **r_failed_dev)
3133 {
3134 	struct ata_port *ap = link->ap;
3135 	struct ata_device *dev;
3136 	int rc = 0, used_dma = 0, found = 0;
3137 
3138 	/* step 1: calculate xfer_mask */
3139 	ata_link_for_each_dev(dev, link) {
3140 		unsigned long pio_mask, dma_mask;
3141 		unsigned int mode_mask;
3142 
3143 		if (!ata_dev_enabled(dev))
3144 			continue;
3145 
3146 		mode_mask = ATA_DMA_MASK_ATA;
3147 		if (dev->class == ATA_DEV_ATAPI)
3148 			mode_mask = ATA_DMA_MASK_ATAPI;
3149 		else if (ata_id_is_cfa(dev->id))
3150 			mode_mask = ATA_DMA_MASK_CFA;
3151 
3152 		ata_dev_xfermask(dev);
3153 
3154 		pio_mask = ata_pack_xfermask(dev->pio_mask, 0, 0);
3155 		dma_mask = ata_pack_xfermask(0, dev->mwdma_mask, dev->udma_mask);
3156 
3157 		if (libata_dma_mask & mode_mask)
3158 			dma_mask = ata_pack_xfermask(0, dev->mwdma_mask, dev->udma_mask);
3159 		else
3160 			dma_mask = 0;
3161 
3162 		dev->pio_mode = ata_xfer_mask2mode(pio_mask);
3163 		dev->dma_mode = ata_xfer_mask2mode(dma_mask);
3164 
3165 		found = 1;
3166 		if (dev->dma_mode != 0xff)
3167 			used_dma = 1;
3168 	}
3169 	if (!found)
3170 		goto out;
3171 
3172 	/* step 2: always set host PIO timings */
3173 	ata_link_for_each_dev(dev, link) {
3174 		if (!ata_dev_enabled(dev))
3175 			continue;
3176 
3177 		if (dev->pio_mode == 0xff) {
3178 			ata_dev_printk(dev, KERN_WARNING, "no PIO support\n");
3179 			rc = -EINVAL;
3180 			goto out;
3181 		}
3182 
3183 		dev->xfer_mode = dev->pio_mode;
3184 		dev->xfer_shift = ATA_SHIFT_PIO;
3185 		if (ap->ops->set_piomode)
3186 			ap->ops->set_piomode(ap, dev);
3187 	}
3188 
3189 	/* step 3: set host DMA timings */
3190 	ata_link_for_each_dev(dev, link) {
3191 		if (!ata_dev_enabled(dev) || dev->dma_mode == 0xff)
3192 			continue;
3193 
3194 		dev->xfer_mode = dev->dma_mode;
3195 		dev->xfer_shift = ata_xfer_mode2shift(dev->dma_mode);
3196 		if (ap->ops->set_dmamode)
3197 			ap->ops->set_dmamode(ap, dev);
3198 	}
3199 
3200 	/* step 4: update devices' xfer mode */
3201 	ata_link_for_each_dev(dev, link) {
3202 		/* don't update suspended devices' xfer mode */
3203 		if (!ata_dev_enabled(dev))
3204 			continue;
3205 
3206 		rc = ata_dev_set_mode(dev);
3207 		if (rc)
3208 			goto out;
3209 	}
3210 
3211 	/* Record simplex status. If we selected DMA then the other
3212 	 * host channels are not permitted to do so.
3213 	 */
3214 	if (used_dma && (ap->host->flags & ATA_HOST_SIMPLEX))
3215 		ap->host->simplex_claimed = ap;
3216 
3217  out:
3218 	if (rc)
3219 		*r_failed_dev = dev;
3220 	return rc;
3221 }
3222 
3223 /**
3224  *	ata_tf_to_host - issue ATA taskfile to host controller
3225  *	@ap: port to which command is being issued
3226  *	@tf: ATA taskfile register set
3227  *
3228  *	Issues ATA taskfile register set to ATA host controller,
3229  *	with proper synchronization with interrupt handler and
3230  *	other threads.
3231  *
3232  *	LOCKING:
3233  *	spin_lock_irqsave(host lock)
3234  */
3235 
3236 static inline void ata_tf_to_host(struct ata_port *ap,
3237 				  const struct ata_taskfile *tf)
3238 {
3239 	ap->ops->tf_load(ap, tf);
3240 	ap->ops->exec_command(ap, tf);
3241 }
3242 
3243 /**
3244  *	ata_busy_sleep - sleep until BSY clears, or timeout
3245  *	@ap: port containing status register to be polled
3246  *	@tmout_pat: impatience timeout
3247  *	@tmout: overall timeout
3248  *
3249  *	Sleep until ATA Status register bit BSY clears,
3250  *	or a timeout occurs.
3251  *
3252  *	LOCKING:
3253  *	Kernel thread context (may sleep).
3254  *
3255  *	RETURNS:
3256  *	0 on success, -errno otherwise.
3257  */
3258 int ata_busy_sleep(struct ata_port *ap,
3259 		   unsigned long tmout_pat, unsigned long tmout)
3260 {
3261 	unsigned long timer_start, timeout;
3262 	u8 status;
3263 
3264 	status = ata_busy_wait(ap, ATA_BUSY, 300);
3265 	timer_start = jiffies;
3266 	timeout = timer_start + tmout_pat;
3267 	while (status != 0xff && (status & ATA_BUSY) &&
3268 	       time_before(jiffies, timeout)) {
3269 		msleep(50);
3270 		status = ata_busy_wait(ap, ATA_BUSY, 3);
3271 	}
3272 
3273 	if (status != 0xff && (status & ATA_BUSY))
3274 		ata_port_printk(ap, KERN_WARNING,
3275 				"port is slow to respond, please be patient "
3276 				"(Status 0x%x)\n", status);
3277 
3278 	timeout = timer_start + tmout;
3279 	while (status != 0xff && (status & ATA_BUSY) &&
3280 	       time_before(jiffies, timeout)) {
3281 		msleep(50);
3282 		status = ata_chk_status(ap);
3283 	}
3284 
3285 	if (status == 0xff)
3286 		return -ENODEV;
3287 
3288 	if (status & ATA_BUSY) {
3289 		ata_port_printk(ap, KERN_ERR, "port failed to respond "
3290 				"(%lu secs, Status 0x%x)\n",
3291 				tmout / HZ, status);
3292 		return -EBUSY;
3293 	}
3294 
3295 	return 0;
3296 }
3297 
3298 /**
3299  *	ata_wait_after_reset - wait before checking status after reset
3300  *	@ap: port containing status register to be polled
3301  *	@deadline: deadline jiffies for the operation
3302  *
3303  *	After reset, we need to pause a while before reading status.
3304  *	Also, certain combination of controller and device report 0xff
3305  *	for some duration (e.g. until SATA PHY is up and running)
3306  *	which is interpreted as empty port in ATA world.  This
3307  *	function also waits for such devices to get out of 0xff
3308  *	status.
3309  *
3310  *	LOCKING:
3311  *	Kernel thread context (may sleep).
3312  */
3313 void ata_wait_after_reset(struct ata_port *ap, unsigned long deadline)
3314 {
3315 	unsigned long until = jiffies + ATA_TMOUT_FF_WAIT;
3316 
3317 	if (time_before(until, deadline))
3318 		deadline = until;
3319 
3320 	/* Spec mandates ">= 2ms" before checking status.  We wait
3321 	 * 150ms, because that was the magic delay used for ATAPI
3322 	 * devices in Hale Landis's ATADRVR, for the period of time
3323 	 * between when the ATA command register is written, and then
3324 	 * status is checked.  Because waiting for "a while" before
3325 	 * checking status is fine, post SRST, we perform this magic
3326 	 * delay here as well.
3327 	 *
3328 	 * Old drivers/ide uses the 2mS rule and then waits for ready.
3329 	 */
3330 	msleep(150);
3331 
3332 	/* Wait for 0xff to clear.  Some SATA devices take a long time
3333 	 * to clear 0xff after reset.  For example, HHD424020F7SV00
3334 	 * iVDR needs >= 800ms while.  Quantum GoVault needs even more
3335 	 * than that.
3336 	 *
3337 	 * Note that some PATA controllers (pata_ali) explode if
3338 	 * status register is read more than once when there's no
3339 	 * device attached.
3340 	 */
3341 	if (ap->flags & ATA_FLAG_SATA) {
3342 		while (1) {
3343 			u8 status = ata_chk_status(ap);
3344 
3345 			if (status != 0xff || time_after(jiffies, deadline))
3346 				return;
3347 
3348 			msleep(50);
3349 		}
3350 	}
3351 }
3352 
3353 /**
3354  *	ata_wait_ready - sleep until BSY clears, or timeout
3355  *	@ap: port containing status register to be polled
3356  *	@deadline: deadline jiffies for the operation
3357  *
3358  *	Sleep until ATA Status register bit BSY clears, or timeout
3359  *	occurs.
3360  *
3361  *	LOCKING:
3362  *	Kernel thread context (may sleep).
3363  *
3364  *	RETURNS:
3365  *	0 on success, -errno otherwise.
3366  */
3367 int ata_wait_ready(struct ata_port *ap, unsigned long deadline)
3368 {
3369 	unsigned long start = jiffies;
3370 	int warned = 0;
3371 
3372 	while (1) {
3373 		u8 status = ata_chk_status(ap);
3374 		unsigned long now = jiffies;
3375 
3376 		if (!(status & ATA_BUSY))
3377 			return 0;
3378 		if (!ata_link_online(&ap->link) && status == 0xff)
3379 			return -ENODEV;
3380 		if (time_after(now, deadline))
3381 			return -EBUSY;
3382 
3383 		if (!warned && time_after(now, start + 5 * HZ) &&
3384 		    (deadline - now > 3 * HZ)) {
3385 			ata_port_printk(ap, KERN_WARNING,
3386 				"port is slow to respond, please be patient "
3387 				"(Status 0x%x)\n", status);
3388 			warned = 1;
3389 		}
3390 
3391 		msleep(50);
3392 	}
3393 }
3394 
3395 static int ata_bus_post_reset(struct ata_port *ap, unsigned int devmask,
3396 			      unsigned long deadline)
3397 {
3398 	struct ata_ioports *ioaddr = &ap->ioaddr;
3399 	unsigned int dev0 = devmask & (1 << 0);
3400 	unsigned int dev1 = devmask & (1 << 1);
3401 	int rc, ret = 0;
3402 
3403 	/* if device 0 was found in ata_devchk, wait for its
3404 	 * BSY bit to clear
3405 	 */
3406 	if (dev0) {
3407 		rc = ata_wait_ready(ap, deadline);
3408 		if (rc) {
3409 			if (rc != -ENODEV)
3410 				return rc;
3411 			ret = rc;
3412 		}
3413 	}
3414 
3415 	/* if device 1 was found in ata_devchk, wait for register
3416 	 * access briefly, then wait for BSY to clear.
3417 	 */
3418 	if (dev1) {
3419 		int i;
3420 
3421 		ap->ops->dev_select(ap, 1);
3422 
3423 		/* Wait for register access.  Some ATAPI devices fail
3424 		 * to set nsect/lbal after reset, so don't waste too
3425 		 * much time on it.  We're gonna wait for !BSY anyway.
3426 		 */
3427 		for (i = 0; i < 2; i++) {
3428 			u8 nsect, lbal;
3429 
3430 			nsect = ioread8(ioaddr->nsect_addr);
3431 			lbal = ioread8(ioaddr->lbal_addr);
3432 			if ((nsect == 1) && (lbal == 1))
3433 				break;
3434 			msleep(50);	/* give drive a breather */
3435 		}
3436 
3437 		rc = ata_wait_ready(ap, deadline);
3438 		if (rc) {
3439 			if (rc != -ENODEV)
3440 				return rc;
3441 			ret = rc;
3442 		}
3443 	}
3444 
3445 	/* is all this really necessary? */
3446 	ap->ops->dev_select(ap, 0);
3447 	if (dev1)
3448 		ap->ops->dev_select(ap, 1);
3449 	if (dev0)
3450 		ap->ops->dev_select(ap, 0);
3451 
3452 	return ret;
3453 }
3454 
3455 static int ata_bus_softreset(struct ata_port *ap, unsigned int devmask,
3456 			     unsigned long deadline)
3457 {
3458 	struct ata_ioports *ioaddr = &ap->ioaddr;
3459 
3460 	DPRINTK("ata%u: bus reset via SRST\n", ap->print_id);
3461 
3462 	/* software reset.  causes dev0 to be selected */
3463 	iowrite8(ap->ctl, ioaddr->ctl_addr);
3464 	udelay(20);	/* FIXME: flush */
3465 	iowrite8(ap->ctl | ATA_SRST, ioaddr->ctl_addr);
3466 	udelay(20);	/* FIXME: flush */
3467 	iowrite8(ap->ctl, ioaddr->ctl_addr);
3468 
3469 	/* wait a while before checking status */
3470 	ata_wait_after_reset(ap, deadline);
3471 
3472 	/* Before we perform post reset processing we want to see if
3473 	 * the bus shows 0xFF because the odd clown forgets the D7
3474 	 * pulldown resistor.
3475 	 */
3476 	if (ata_chk_status(ap) == 0xFF)
3477 		return -ENODEV;
3478 
3479 	return ata_bus_post_reset(ap, devmask, deadline);
3480 }
3481 
3482 /**
3483  *	ata_bus_reset - reset host port and associated ATA channel
3484  *	@ap: port to reset
3485  *
3486  *	This is typically the first time we actually start issuing
3487  *	commands to the ATA channel.  We wait for BSY to clear, then
3488  *	issue EXECUTE DEVICE DIAGNOSTIC command, polling for its
3489  *	result.  Determine what devices, if any, are on the channel
3490  *	by looking at the device 0/1 error register.  Look at the signature
3491  *	stored in each device's taskfile registers, to determine if
3492  *	the device is ATA or ATAPI.
3493  *
3494  *	LOCKING:
3495  *	PCI/etc. bus probe sem.
3496  *	Obtains host lock.
3497  *
3498  *	SIDE EFFECTS:
3499  *	Sets ATA_FLAG_DISABLED if bus reset fails.
3500  */
3501 
3502 void ata_bus_reset(struct ata_port *ap)
3503 {
3504 	struct ata_device *device = ap->link.device;
3505 	struct ata_ioports *ioaddr = &ap->ioaddr;
3506 	unsigned int slave_possible = ap->flags & ATA_FLAG_SLAVE_POSS;
3507 	u8 err;
3508 	unsigned int dev0, dev1 = 0, devmask = 0;
3509 	int rc;
3510 
3511 	DPRINTK("ENTER, host %u, port %u\n", ap->print_id, ap->port_no);
3512 
3513 	/* determine if device 0/1 are present */
3514 	if (ap->flags & ATA_FLAG_SATA_RESET)
3515 		dev0 = 1;
3516 	else {
3517 		dev0 = ata_devchk(ap, 0);
3518 		if (slave_possible)
3519 			dev1 = ata_devchk(ap, 1);
3520 	}
3521 
3522 	if (dev0)
3523 		devmask |= (1 << 0);
3524 	if (dev1)
3525 		devmask |= (1 << 1);
3526 
3527 	/* select device 0 again */
3528 	ap->ops->dev_select(ap, 0);
3529 
3530 	/* issue bus reset */
3531 	if (ap->flags & ATA_FLAG_SRST) {
3532 		rc = ata_bus_softreset(ap, devmask, jiffies + 40 * HZ);
3533 		if (rc && rc != -ENODEV)
3534 			goto err_out;
3535 	}
3536 
3537 	/*
3538 	 * determine by signature whether we have ATA or ATAPI devices
3539 	 */
3540 	device[0].class = ata_dev_try_classify(&device[0], dev0, &err);
3541 	if ((slave_possible) && (err != 0x81))
3542 		device[1].class = ata_dev_try_classify(&device[1], dev1, &err);
3543 
3544 	/* is double-select really necessary? */
3545 	if (device[1].class != ATA_DEV_NONE)
3546 		ap->ops->dev_select(ap, 1);
3547 	if (device[0].class != ATA_DEV_NONE)
3548 		ap->ops->dev_select(ap, 0);
3549 
3550 	/* if no devices were detected, disable this port */
3551 	if ((device[0].class == ATA_DEV_NONE) &&
3552 	    (device[1].class == ATA_DEV_NONE))
3553 		goto err_out;
3554 
3555 	if (ap->flags & (ATA_FLAG_SATA_RESET | ATA_FLAG_SRST)) {
3556 		/* set up device control for ATA_FLAG_SATA_RESET */
3557 		iowrite8(ap->ctl, ioaddr->ctl_addr);
3558 	}
3559 
3560 	DPRINTK("EXIT\n");
3561 	return;
3562 
3563 err_out:
3564 	ata_port_printk(ap, KERN_ERR, "disabling port\n");
3565 	ata_port_disable(ap);
3566 
3567 	DPRINTK("EXIT\n");
3568 }
3569 
3570 /**
3571  *	sata_link_debounce - debounce SATA phy status
3572  *	@link: ATA link to debounce SATA phy status for
3573  *	@params: timing parameters { interval, duratinon, timeout } in msec
3574  *	@deadline: deadline jiffies for the operation
3575  *
3576 *	Make sure SStatus of @link reaches stable state, determined by
3577  *	holding the same value where DET is not 1 for @duration polled
3578  *	every @interval, before @timeout.  Timeout constraints the
3579  *	beginning of the stable state.  Because DET gets stuck at 1 on
3580  *	some controllers after hot unplugging, this functions waits
3581  *	until timeout then returns 0 if DET is stable at 1.
3582  *
3583  *	@timeout is further limited by @deadline.  The sooner of the
3584  *	two is used.
3585  *
3586  *	LOCKING:
3587  *	Kernel thread context (may sleep)
3588  *
3589  *	RETURNS:
3590  *	0 on success, -errno on failure.
3591  */
3592 int sata_link_debounce(struct ata_link *link, const unsigned long *params,
3593 		       unsigned long deadline)
3594 {
3595 	unsigned long interval_msec = params[0];
3596 	unsigned long duration = msecs_to_jiffies(params[1]);
3597 	unsigned long last_jiffies, t;
3598 	u32 last, cur;
3599 	int rc;
3600 
3601 	t = jiffies + msecs_to_jiffies(params[2]);
3602 	if (time_before(t, deadline))
3603 		deadline = t;
3604 
3605 	if ((rc = sata_scr_read(link, SCR_STATUS, &cur)))
3606 		return rc;
3607 	cur &= 0xf;
3608 
3609 	last = cur;
3610 	last_jiffies = jiffies;
3611 
3612 	while (1) {
3613 		msleep(interval_msec);
3614 		if ((rc = sata_scr_read(link, SCR_STATUS, &cur)))
3615 			return rc;
3616 		cur &= 0xf;
3617 
3618 		/* DET stable? */
3619 		if (cur == last) {
3620 			if (cur == 1 && time_before(jiffies, deadline))
3621 				continue;
3622 			if (time_after(jiffies, last_jiffies + duration))
3623 				return 0;
3624 			continue;
3625 		}
3626 
3627 		/* unstable, start over */
3628 		last = cur;
3629 		last_jiffies = jiffies;
3630 
3631 		/* Check deadline.  If debouncing failed, return
3632 		 * -EPIPE to tell upper layer to lower link speed.
3633 		 */
3634 		if (time_after(jiffies, deadline))
3635 			return -EPIPE;
3636 	}
3637 }
3638 
3639 /**
3640  *	sata_link_resume - resume SATA link
3641  *	@link: ATA link to resume SATA
3642  *	@params: timing parameters { interval, duratinon, timeout } in msec
3643  *	@deadline: deadline jiffies for the operation
3644  *
3645  *	Resume SATA phy @link and debounce it.
3646  *
3647  *	LOCKING:
3648  *	Kernel thread context (may sleep)
3649  *
3650  *	RETURNS:
3651  *	0 on success, -errno on failure.
3652  */
3653 int sata_link_resume(struct ata_link *link, const unsigned long *params,
3654 		     unsigned long deadline)
3655 {
3656 	u32 scontrol;
3657 	int rc;
3658 
3659 	if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3660 		return rc;
3661 
3662 	scontrol = (scontrol & 0x0f0) | 0x300;
3663 
3664 	if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
3665 		return rc;
3666 
3667 	/* Some PHYs react badly if SStatus is pounded immediately
3668 	 * after resuming.  Delay 200ms before debouncing.
3669 	 */
3670 	msleep(200);
3671 
3672 	return sata_link_debounce(link, params, deadline);
3673 }
3674 
3675 /**
3676  *	ata_std_prereset - prepare for reset
3677  *	@link: ATA link to be reset
3678  *	@deadline: deadline jiffies for the operation
3679  *
3680  *	@link is about to be reset.  Initialize it.  Failure from
3681  *	prereset makes libata abort whole reset sequence and give up
3682  *	that port, so prereset should be best-effort.  It does its
3683  *	best to prepare for reset sequence but if things go wrong, it
3684  *	should just whine, not fail.
3685  *
3686  *	LOCKING:
3687  *	Kernel thread context (may sleep)
3688  *
3689  *	RETURNS:
3690  *	0 on success, -errno otherwise.
3691  */
3692 int ata_std_prereset(struct ata_link *link, unsigned long deadline)
3693 {
3694 	struct ata_port *ap = link->ap;
3695 	struct ata_eh_context *ehc = &link->eh_context;
3696 	const unsigned long *timing = sata_ehc_deb_timing(ehc);
3697 	int rc;
3698 
3699 	/* handle link resume */
3700 	if ((ehc->i.flags & ATA_EHI_RESUME_LINK) &&
3701 	    (link->flags & ATA_LFLAG_HRST_TO_RESUME))
3702 		ehc->i.action |= ATA_EH_HARDRESET;
3703 
3704 	/* Some PMPs don't work with only SRST, force hardreset if PMP
3705 	 * is supported.
3706 	 */
3707 	if (ap->flags & ATA_FLAG_PMP)
3708 		ehc->i.action |= ATA_EH_HARDRESET;
3709 
3710 	/* if we're about to do hardreset, nothing more to do */
3711 	if (ehc->i.action & ATA_EH_HARDRESET)
3712 		return 0;
3713 
3714 	/* if SATA, resume link */
3715 	if (ap->flags & ATA_FLAG_SATA) {
3716 		rc = sata_link_resume(link, timing, deadline);
3717 		/* whine about phy resume failure but proceed */
3718 		if (rc && rc != -EOPNOTSUPP)
3719 			ata_link_printk(link, KERN_WARNING, "failed to resume "
3720 					"link for reset (errno=%d)\n", rc);
3721 	}
3722 
3723 	/* Wait for !BSY if the controller can wait for the first D2H
3724 	 * Reg FIS and we don't know that no device is attached.
3725 	 */
3726 	if (!(link->flags & ATA_LFLAG_SKIP_D2H_BSY) && !ata_link_offline(link)) {
3727 		rc = ata_wait_ready(ap, deadline);
3728 		if (rc && rc != -ENODEV) {
3729 			ata_link_printk(link, KERN_WARNING, "device not ready "
3730 					"(errno=%d), forcing hardreset\n", rc);
3731 			ehc->i.action |= ATA_EH_HARDRESET;
3732 		}
3733 	}
3734 
3735 	return 0;
3736 }
3737 
3738 /**
3739  *	ata_std_softreset - reset host port via ATA SRST
3740  *	@link: ATA link to reset
3741  *	@classes: resulting classes of attached devices
3742  *	@deadline: deadline jiffies for the operation
3743  *
3744  *	Reset host port using ATA SRST.
3745  *
3746  *	LOCKING:
3747  *	Kernel thread context (may sleep)
3748  *
3749  *	RETURNS:
3750  *	0 on success, -errno otherwise.
3751  */
3752 int ata_std_softreset(struct ata_link *link, unsigned int *classes,
3753 		      unsigned long deadline)
3754 {
3755 	struct ata_port *ap = link->ap;
3756 	unsigned int slave_possible = ap->flags & ATA_FLAG_SLAVE_POSS;
3757 	unsigned int devmask = 0;
3758 	int rc;
3759 	u8 err;
3760 
3761 	DPRINTK("ENTER\n");
3762 
3763 	if (ata_link_offline(link)) {
3764 		classes[0] = ATA_DEV_NONE;
3765 		goto out;
3766 	}
3767 
3768 	/* determine if device 0/1 are present */
3769 	if (ata_devchk(ap, 0))
3770 		devmask |= (1 << 0);
3771 	if (slave_possible && ata_devchk(ap, 1))
3772 		devmask |= (1 << 1);
3773 
3774 	/* select device 0 again */
3775 	ap->ops->dev_select(ap, 0);
3776 
3777 	/* issue bus reset */
3778 	DPRINTK("about to softreset, devmask=%x\n", devmask);
3779 	rc = ata_bus_softreset(ap, devmask, deadline);
3780 	/* if link is occupied, -ENODEV too is an error */
3781 	if (rc && (rc != -ENODEV || sata_scr_valid(link))) {
3782 		ata_link_printk(link, KERN_ERR, "SRST failed (errno=%d)\n", rc);
3783 		return rc;
3784 	}
3785 
3786 	/* determine by signature whether we have ATA or ATAPI devices */
3787 	classes[0] = ata_dev_try_classify(&link->device[0],
3788 					  devmask & (1 << 0), &err);
3789 	if (slave_possible && err != 0x81)
3790 		classes[1] = ata_dev_try_classify(&link->device[1],
3791 						  devmask & (1 << 1), &err);
3792 
3793  out:
3794 	DPRINTK("EXIT, classes[0]=%u [1]=%u\n", classes[0], classes[1]);
3795 	return 0;
3796 }
3797 
3798 /**
3799  *	sata_link_hardreset - reset link via SATA phy reset
3800  *	@link: link to reset
3801  *	@timing: timing parameters { interval, duratinon, timeout } in msec
3802  *	@deadline: deadline jiffies for the operation
3803  *
3804  *	SATA phy-reset @link using DET bits of SControl register.
3805  *
3806  *	LOCKING:
3807  *	Kernel thread context (may sleep)
3808  *
3809  *	RETURNS:
3810  *	0 on success, -errno otherwise.
3811  */
3812 int sata_link_hardreset(struct ata_link *link, const unsigned long *timing,
3813 			unsigned long deadline)
3814 {
3815 	u32 scontrol;
3816 	int rc;
3817 
3818 	DPRINTK("ENTER\n");
3819 
3820 	if (sata_set_spd_needed(link)) {
3821 		/* SATA spec says nothing about how to reconfigure
3822 		 * spd.  To be on the safe side, turn off phy during
3823 		 * reconfiguration.  This works for at least ICH7 AHCI
3824 		 * and Sil3124.
3825 		 */
3826 		if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3827 			goto out;
3828 
3829 		scontrol = (scontrol & 0x0f0) | 0x304;
3830 
3831 		if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol)))
3832 			goto out;
3833 
3834 		sata_set_spd(link);
3835 	}
3836 
3837 	/* issue phy wake/reset */
3838 	if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol)))
3839 		goto out;
3840 
3841 	scontrol = (scontrol & 0x0f0) | 0x301;
3842 
3843 	if ((rc = sata_scr_write_flush(link, SCR_CONTROL, scontrol)))
3844 		goto out;
3845 
3846 	/* Couldn't find anything in SATA I/II specs, but AHCI-1.1
3847 	 * 10.4.2 says at least 1 ms.
3848 	 */
3849 	msleep(1);
3850 
3851 	/* bring link back */
3852 	rc = sata_link_resume(link, timing, deadline);
3853  out:
3854 	DPRINTK("EXIT, rc=%d\n", rc);
3855 	return rc;
3856 }
3857 
3858 /**
3859  *	sata_std_hardreset - reset host port via SATA phy reset
3860  *	@link: link to reset
3861  *	@class: resulting class of attached device
3862  *	@deadline: deadline jiffies for the operation
3863  *
3864  *	SATA phy-reset host port using DET bits of SControl register,
3865  *	wait for !BSY and classify the attached device.
3866  *
3867  *	LOCKING:
3868  *	Kernel thread context (may sleep)
3869  *
3870  *	RETURNS:
3871  *	0 on success, -errno otherwise.
3872  */
3873 int sata_std_hardreset(struct ata_link *link, unsigned int *class,
3874 		       unsigned long deadline)
3875 {
3876 	struct ata_port *ap = link->ap;
3877 	const unsigned long *timing = sata_ehc_deb_timing(&link->eh_context);
3878 	int rc;
3879 
3880 	DPRINTK("ENTER\n");
3881 
3882 	/* do hardreset */
3883 	rc = sata_link_hardreset(link, timing, deadline);
3884 	if (rc) {
3885 		ata_link_printk(link, KERN_ERR,
3886 				"COMRESET failed (errno=%d)\n", rc);
3887 		return rc;
3888 	}
3889 
3890 	/* TODO: phy layer with polling, timeouts, etc. */
3891 	if (ata_link_offline(link)) {
3892 		*class = ATA_DEV_NONE;
3893 		DPRINTK("EXIT, link offline\n");
3894 		return 0;
3895 	}
3896 
3897 	/* wait a while before checking status */
3898 	ata_wait_after_reset(ap, deadline);
3899 
3900 	/* If PMP is supported, we have to do follow-up SRST.  Note
3901 	 * that some PMPs don't send D2H Reg FIS after hardreset at
3902 	 * all if the first port is empty.  Wait for it just for a
3903 	 * second and request follow-up SRST.
3904 	 */
3905 	if (ap->flags & ATA_FLAG_PMP) {
3906 		ata_wait_ready(ap, jiffies + HZ);
3907 		return -EAGAIN;
3908 	}
3909 
3910 	rc = ata_wait_ready(ap, deadline);
3911 	/* link occupied, -ENODEV too is an error */
3912 	if (rc) {
3913 		ata_link_printk(link, KERN_ERR,
3914 				"COMRESET failed (errno=%d)\n", rc);
3915 		return rc;
3916 	}
3917 
3918 	ap->ops->dev_select(ap, 0);	/* probably unnecessary */
3919 
3920 	*class = ata_dev_try_classify(link->device, 1, NULL);
3921 
3922 	DPRINTK("EXIT, class=%u\n", *class);
3923 	return 0;
3924 }
3925 
3926 /**
3927  *	ata_std_postreset - standard postreset callback
3928  *	@link: the target ata_link
3929  *	@classes: classes of attached devices
3930  *
3931  *	This function is invoked after a successful reset.  Note that
3932  *	the device might have been reset more than once using
3933  *	different reset methods before postreset is invoked.
3934  *
3935  *	LOCKING:
3936  *	Kernel thread context (may sleep)
3937  */
3938 void ata_std_postreset(struct ata_link *link, unsigned int *classes)
3939 {
3940 	struct ata_port *ap = link->ap;
3941 	u32 serror;
3942 
3943 	DPRINTK("ENTER\n");
3944 
3945 	/* print link status */
3946 	sata_print_link_status(link);
3947 
3948 	/* clear SError */
3949 	if (sata_scr_read(link, SCR_ERROR, &serror) == 0)
3950 		sata_scr_write(link, SCR_ERROR, serror);
3951 	link->eh_info.serror = 0;
3952 
3953 	/* is double-select really necessary? */
3954 	if (classes[0] != ATA_DEV_NONE)
3955 		ap->ops->dev_select(ap, 1);
3956 	if (classes[1] != ATA_DEV_NONE)
3957 		ap->ops->dev_select(ap, 0);
3958 
3959 	/* bail out if no device is present */
3960 	if (classes[0] == ATA_DEV_NONE && classes[1] == ATA_DEV_NONE) {
3961 		DPRINTK("EXIT, no device\n");
3962 		return;
3963 	}
3964 
3965 	/* set up device control */
3966 	if (ap->ioaddr.ctl_addr)
3967 		iowrite8(ap->ctl, ap->ioaddr.ctl_addr);
3968 
3969 	DPRINTK("EXIT\n");
3970 }
3971 
3972 /**
3973  *	ata_dev_same_device - Determine whether new ID matches configured device
3974  *	@dev: device to compare against
3975  *	@new_class: class of the new device
3976  *	@new_id: IDENTIFY page of the new device
3977  *
3978  *	Compare @new_class and @new_id against @dev and determine
3979  *	whether @dev is the device indicated by @new_class and
3980  *	@new_id.
3981  *
3982  *	LOCKING:
3983  *	None.
3984  *
3985  *	RETURNS:
3986  *	1 if @dev matches @new_class and @new_id, 0 otherwise.
3987  */
3988 static int ata_dev_same_device(struct ata_device *dev, unsigned int new_class,
3989 			       const u16 *new_id)
3990 {
3991 	const u16 *old_id = dev->id;
3992 	unsigned char model[2][ATA_ID_PROD_LEN + 1];
3993 	unsigned char serial[2][ATA_ID_SERNO_LEN + 1];
3994 
3995 	if (dev->class != new_class) {
3996 		ata_dev_printk(dev, KERN_INFO, "class mismatch %d != %d\n",
3997 			       dev->class, new_class);
3998 		return 0;
3999 	}
4000 
4001 	ata_id_c_string(old_id, model[0], ATA_ID_PROD, sizeof(model[0]));
4002 	ata_id_c_string(new_id, model[1], ATA_ID_PROD, sizeof(model[1]));
4003 	ata_id_c_string(old_id, serial[0], ATA_ID_SERNO, sizeof(serial[0]));
4004 	ata_id_c_string(new_id, serial[1], ATA_ID_SERNO, sizeof(serial[1]));
4005 
4006 	if (strcmp(model[0], model[1])) {
4007 		ata_dev_printk(dev, KERN_INFO, "model number mismatch "
4008 			       "'%s' != '%s'\n", model[0], model[1]);
4009 		return 0;
4010 	}
4011 
4012 	if (strcmp(serial[0], serial[1])) {
4013 		ata_dev_printk(dev, KERN_INFO, "serial number mismatch "
4014 			       "'%s' != '%s'\n", serial[0], serial[1]);
4015 		return 0;
4016 	}
4017 
4018 	return 1;
4019 }
4020 
4021 /**
4022  *	ata_dev_reread_id - Re-read IDENTIFY data
4023  *	@dev: target ATA device
4024  *	@readid_flags: read ID flags
4025  *
4026  *	Re-read IDENTIFY page and make sure @dev is still attached to
4027  *	the port.
4028  *
4029  *	LOCKING:
4030  *	Kernel thread context (may sleep)
4031  *
4032  *	RETURNS:
4033  *	0 on success, negative errno otherwise
4034  */
4035 int ata_dev_reread_id(struct ata_device *dev, unsigned int readid_flags)
4036 {
4037 	unsigned int class = dev->class;
4038 	u16 *id = (void *)dev->link->ap->sector_buf;
4039 	int rc;
4040 
4041 	/* read ID data */
4042 	rc = ata_dev_read_id(dev, &class, readid_flags, id);
4043 	if (rc)
4044 		return rc;
4045 
4046 	/* is the device still there? */
4047 	if (!ata_dev_same_device(dev, class, id))
4048 		return -ENODEV;
4049 
4050 	memcpy(dev->id, id, sizeof(id[0]) * ATA_ID_WORDS);
4051 	return 0;
4052 }
4053 
4054 /**
4055  *	ata_dev_revalidate - Revalidate ATA device
4056  *	@dev: device to revalidate
4057  *	@new_class: new class code
4058  *	@readid_flags: read ID flags
4059  *
4060  *	Re-read IDENTIFY page, make sure @dev is still attached to the
4061  *	port and reconfigure it according to the new IDENTIFY page.
4062  *
4063  *	LOCKING:
4064  *	Kernel thread context (may sleep)
4065  *
4066  *	RETURNS:
4067  *	0 on success, negative errno otherwise
4068  */
4069 int ata_dev_revalidate(struct ata_device *dev, unsigned int new_class,
4070 		       unsigned int readid_flags)
4071 {
4072 	u64 n_sectors = dev->n_sectors;
4073 	int rc;
4074 
4075 	if (!ata_dev_enabled(dev))
4076 		return -ENODEV;
4077 
4078 	/* fail early if !ATA && !ATAPI to avoid issuing [P]IDENTIFY to PMP */
4079 	if (ata_class_enabled(new_class) &&
4080 	    new_class != ATA_DEV_ATA && new_class != ATA_DEV_ATAPI) {
4081 		ata_dev_printk(dev, KERN_INFO, "class mismatch %u != %u\n",
4082 			       dev->class, new_class);
4083 		rc = -ENODEV;
4084 		goto fail;
4085 	}
4086 
4087 	/* re-read ID */
4088 	rc = ata_dev_reread_id(dev, readid_flags);
4089 	if (rc)
4090 		goto fail;
4091 
4092 	/* configure device according to the new ID */
4093 	rc = ata_dev_configure(dev);
4094 	if (rc)
4095 		goto fail;
4096 
4097 	/* verify n_sectors hasn't changed */
4098 	if (dev->class == ATA_DEV_ATA && n_sectors &&
4099 	    dev->n_sectors != n_sectors) {
4100 		ata_dev_printk(dev, KERN_INFO, "n_sectors mismatch "
4101 			       "%llu != %llu\n",
4102 			       (unsigned long long)n_sectors,
4103 			       (unsigned long long)dev->n_sectors);
4104 
4105 		/* restore original n_sectors */
4106 		dev->n_sectors = n_sectors;
4107 
4108 		rc = -ENODEV;
4109 		goto fail;
4110 	}
4111 
4112 	return 0;
4113 
4114  fail:
4115 	ata_dev_printk(dev, KERN_ERR, "revalidation failed (errno=%d)\n", rc);
4116 	return rc;
4117 }
4118 
4119 struct ata_blacklist_entry {
4120 	const char *model_num;
4121 	const char *model_rev;
4122 	unsigned long horkage;
4123 };
4124 
4125 static const struct ata_blacklist_entry ata_device_blacklist [] = {
4126 	/* Devices with DMA related problems under Linux */
4127 	{ "WDC AC11000H",	NULL,		ATA_HORKAGE_NODMA },
4128 	{ "WDC AC22100H",	NULL,		ATA_HORKAGE_NODMA },
4129 	{ "WDC AC32500H",	NULL,		ATA_HORKAGE_NODMA },
4130 	{ "WDC AC33100H",	NULL,		ATA_HORKAGE_NODMA },
4131 	{ "WDC AC31600H",	NULL,		ATA_HORKAGE_NODMA },
4132 	{ "WDC AC32100H",	"24.09P07",	ATA_HORKAGE_NODMA },
4133 	{ "WDC AC23200L",	"21.10N21",	ATA_HORKAGE_NODMA },
4134 	{ "Compaq CRD-8241B", 	NULL,		ATA_HORKAGE_NODMA },
4135 	{ "CRD-8400B",		NULL, 		ATA_HORKAGE_NODMA },
4136 	{ "CRD-8480B",		NULL,		ATA_HORKAGE_NODMA },
4137 	{ "CRD-8482B",		NULL,		ATA_HORKAGE_NODMA },
4138 	{ "CRD-84",		NULL,		ATA_HORKAGE_NODMA },
4139 	{ "SanDisk SDP3B",	NULL,		ATA_HORKAGE_NODMA },
4140 	{ "SanDisk SDP3B-64",	NULL,		ATA_HORKAGE_NODMA },
4141 	{ "SANYO CD-ROM CRD",	NULL,		ATA_HORKAGE_NODMA },
4142 	{ "HITACHI CDR-8",	NULL,		ATA_HORKAGE_NODMA },
4143 	{ "HITACHI CDR-8335",	NULL,		ATA_HORKAGE_NODMA },
4144 	{ "HITACHI CDR-8435",	NULL,		ATA_HORKAGE_NODMA },
4145 	{ "Toshiba CD-ROM XM-6202B", NULL,	ATA_HORKAGE_NODMA },
4146 	{ "TOSHIBA CD-ROM XM-1702BC", NULL,	ATA_HORKAGE_NODMA },
4147 	{ "CD-532E-A", 		NULL,		ATA_HORKAGE_NODMA },
4148 	{ "E-IDE CD-ROM CR-840",NULL,		ATA_HORKAGE_NODMA },
4149 	{ "CD-ROM Drive/F5A",	NULL,		ATA_HORKAGE_NODMA },
4150 	{ "WPI CDD-820", 	NULL,		ATA_HORKAGE_NODMA },
4151 	{ "SAMSUNG CD-ROM SC-148C", NULL,	ATA_HORKAGE_NODMA },
4152 	{ "SAMSUNG CD-ROM SC",	NULL,		ATA_HORKAGE_NODMA },
4153 	{ "ATAPI CD-ROM DRIVE 40X MAXIMUM",NULL,ATA_HORKAGE_NODMA },
4154 	{ "_NEC DV5800A", 	NULL,		ATA_HORKAGE_NODMA },
4155 	{ "SAMSUNG CD-ROM SN-124", "N001",	ATA_HORKAGE_NODMA },
4156 	{ "Seagate STT20000A", NULL,		ATA_HORKAGE_NODMA },
4157 	/* Odd clown on sil3726/4726 PMPs */
4158 	{ "Config  Disk",	NULL,		ATA_HORKAGE_NODMA |
4159 						ATA_HORKAGE_SKIP_PM },
4160 
4161 	/* Weird ATAPI devices */
4162 	{ "TORiSAN DVD-ROM DRD-N216", NULL,	ATA_HORKAGE_MAX_SEC_128 },
4163 
4164 	/* Devices we expect to fail diagnostics */
4165 
4166 	/* Devices where NCQ should be avoided */
4167 	/* NCQ is slow */
4168 	{ "WDC WD740ADFD-00",	NULL,		ATA_HORKAGE_NONCQ },
4169 	{ "WDC WD740ADFD-00NLR1", NULL,		ATA_HORKAGE_NONCQ, },
4170 	/* http://thread.gmane.org/gmane.linux.ide/14907 */
4171 	{ "FUJITSU MHT2060BH",	NULL,		ATA_HORKAGE_NONCQ },
4172 	/* NCQ is broken */
4173 	{ "Maxtor *",		"BANC*",	ATA_HORKAGE_NONCQ },
4174 	{ "Maxtor 7V300F0",	"VA111630",	ATA_HORKAGE_NONCQ },
4175 	{ "ST380817AS",		"3.42",		ATA_HORKAGE_NONCQ },
4176 	{ "ST3160023AS",	"3.42",		ATA_HORKAGE_NONCQ },
4177 
4178 	/* Blacklist entries taken from Silicon Image 3124/3132
4179 	   Windows driver .inf file - also several Linux problem reports */
4180 	{ "HTS541060G9SA00",    "MB3OC60D",     ATA_HORKAGE_NONCQ, },
4181 	{ "HTS541080G9SA00",    "MB4OC60D",     ATA_HORKAGE_NONCQ, },
4182 	{ "HTS541010G9SA00",    "MBZOC60D",     ATA_HORKAGE_NONCQ, },
4183 
4184 	/* devices which puke on READ_NATIVE_MAX */
4185 	{ "HDS724040KLSA80",	"KFAOA20N",	ATA_HORKAGE_BROKEN_HPA, },
4186 	{ "WDC WD3200JD-00KLB0", "WD-WCAMR1130137", ATA_HORKAGE_BROKEN_HPA },
4187 	{ "WDC WD2500JD-00HBB0", "WD-WMAL71490727", ATA_HORKAGE_BROKEN_HPA },
4188 	{ "MAXTOR 6L080L4",	"A93.0500",	ATA_HORKAGE_BROKEN_HPA },
4189 
4190 	/* Devices which report 1 sector over size HPA */
4191 	{ "ST340823A",		NULL,		ATA_HORKAGE_HPA_SIZE, },
4192 	{ "ST320413A",		NULL,		ATA_HORKAGE_HPA_SIZE, },
4193 
4194 	/* Devices which get the IVB wrong */
4195 	{ "QUANTUM FIREBALLlct10 05", "A03.0900", ATA_HORKAGE_IVB, },
4196 	{ "TSSTcorp CDDVDW SH-S202J", "SB00",	  ATA_HORKAGE_IVB, },
4197 	{ "TSSTcorp CDDVDW SH-S202J", "SB01",	  ATA_HORKAGE_IVB, },
4198 	{ "TSSTcorp CDDVDW SH-S202N", "SB00",	  ATA_HORKAGE_IVB, },
4199 	{ "TSSTcorp CDDVDW SH-S202N", "SB01",	  ATA_HORKAGE_IVB, },
4200 
4201 	/* End Marker */
4202 	{ }
4203 };
4204 
4205 static int strn_pattern_cmp(const char *patt, const char *name, int wildchar)
4206 {
4207 	const char *p;
4208 	int len;
4209 
4210 	/*
4211 	 * check for trailing wildcard: *\0
4212 	 */
4213 	p = strchr(patt, wildchar);
4214 	if (p && ((*(p + 1)) == 0))
4215 		len = p - patt;
4216 	else {
4217 		len = strlen(name);
4218 		if (!len) {
4219 			if (!*patt)
4220 				return 0;
4221 			return -1;
4222 		}
4223 	}
4224 
4225 	return strncmp(patt, name, len);
4226 }
4227 
4228 static unsigned long ata_dev_blacklisted(const struct ata_device *dev)
4229 {
4230 	unsigned char model_num[ATA_ID_PROD_LEN + 1];
4231 	unsigned char model_rev[ATA_ID_FW_REV_LEN + 1];
4232 	const struct ata_blacklist_entry *ad = ata_device_blacklist;
4233 
4234 	ata_id_c_string(dev->id, model_num, ATA_ID_PROD, sizeof(model_num));
4235 	ata_id_c_string(dev->id, model_rev, ATA_ID_FW_REV, sizeof(model_rev));
4236 
4237 	while (ad->model_num) {
4238 		if (!strn_pattern_cmp(ad->model_num, model_num, '*')) {
4239 			if (ad->model_rev == NULL)
4240 				return ad->horkage;
4241 			if (!strn_pattern_cmp(ad->model_rev, model_rev, '*'))
4242 				return ad->horkage;
4243 		}
4244 		ad++;
4245 	}
4246 	return 0;
4247 }
4248 
4249 static int ata_dma_blacklisted(const struct ata_device *dev)
4250 {
4251 	/* We don't support polling DMA.
4252 	 * DMA blacklist those ATAPI devices with CDB-intr (and use PIO)
4253 	 * if the LLDD handles only interrupts in the HSM_ST_LAST state.
4254 	 */
4255 	if ((dev->link->ap->flags & ATA_FLAG_PIO_POLLING) &&
4256 	    (dev->flags & ATA_DFLAG_CDB_INTR))
4257 		return 1;
4258 	return (dev->horkage & ATA_HORKAGE_NODMA) ? 1 : 0;
4259 }
4260 
4261 /**
4262  *	ata_is_40wire		-	check drive side detection
4263  *	@dev: device
4264  *
4265  *	Perform drive side detection decoding, allowing for device vendors
4266  *	who can't follow the documentation.
4267  */
4268 
4269 static int ata_is_40wire(struct ata_device *dev)
4270 {
4271 	if (dev->horkage & ATA_HORKAGE_IVB)
4272 		return ata_drive_40wire_relaxed(dev->id);
4273 	return ata_drive_40wire(dev->id);
4274 }
4275 
4276 /**
4277  *	ata_dev_xfermask - Compute supported xfermask of the given device
4278  *	@dev: Device to compute xfermask for
4279  *
4280  *	Compute supported xfermask of @dev and store it in
4281  *	dev->*_mask.  This function is responsible for applying all
4282  *	known limits including host controller limits, device
4283  *	blacklist, etc...
4284  *
4285  *	LOCKING:
4286  *	None.
4287  */
4288 static void ata_dev_xfermask(struct ata_device *dev)
4289 {
4290 	struct ata_link *link = dev->link;
4291 	struct ata_port *ap = link->ap;
4292 	struct ata_host *host = ap->host;
4293 	unsigned long xfer_mask;
4294 
4295 	/* controller modes available */
4296 	xfer_mask = ata_pack_xfermask(ap->pio_mask,
4297 				      ap->mwdma_mask, ap->udma_mask);
4298 
4299 	/* drive modes available */
4300 	xfer_mask &= ata_pack_xfermask(dev->pio_mask,
4301 				       dev->mwdma_mask, dev->udma_mask);
4302 	xfer_mask &= ata_id_xfermask(dev->id);
4303 
4304 	/*
4305 	 *	CFA Advanced TrueIDE timings are not allowed on a shared
4306 	 *	cable
4307 	 */
4308 	if (ata_dev_pair(dev)) {
4309 		/* No PIO5 or PIO6 */
4310 		xfer_mask &= ~(0x03 << (ATA_SHIFT_PIO + 5));
4311 		/* No MWDMA3 or MWDMA 4 */
4312 		xfer_mask &= ~(0x03 << (ATA_SHIFT_MWDMA + 3));
4313 	}
4314 
4315 	if (ata_dma_blacklisted(dev)) {
4316 		xfer_mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA);
4317 		ata_dev_printk(dev, KERN_WARNING,
4318 			       "device is on DMA blacklist, disabling DMA\n");
4319 	}
4320 
4321 	if ((host->flags & ATA_HOST_SIMPLEX) &&
4322 	    host->simplex_claimed && host->simplex_claimed != ap) {
4323 		xfer_mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA);
4324 		ata_dev_printk(dev, KERN_WARNING, "simplex DMA is claimed by "
4325 			       "other device, disabling DMA\n");
4326 	}
4327 
4328 	if (ap->flags & ATA_FLAG_NO_IORDY)
4329 		xfer_mask &= ata_pio_mask_no_iordy(dev);
4330 
4331 	if (ap->ops->mode_filter)
4332 		xfer_mask = ap->ops->mode_filter(dev, xfer_mask);
4333 
4334 	/* Apply cable rule here.  Don't apply it early because when
4335 	 * we handle hot plug the cable type can itself change.
4336 	 * Check this last so that we know if the transfer rate was
4337 	 * solely limited by the cable.
4338 	 * Unknown or 80 wire cables reported host side are checked
4339 	 * drive side as well. Cases where we know a 40wire cable
4340 	 * is used safely for 80 are not checked here.
4341 	 */
4342 	if (xfer_mask & (0xF8 << ATA_SHIFT_UDMA))
4343 		/* UDMA/44 or higher would be available */
4344 		if ((ap->cbl == ATA_CBL_PATA40) ||
4345 		    (ata_is_40wire(dev) &&
4346 		    (ap->cbl == ATA_CBL_PATA_UNK ||
4347 		     ap->cbl == ATA_CBL_PATA80))) {
4348 			ata_dev_printk(dev, KERN_WARNING,
4349 				 "limited to UDMA/33 due to 40-wire cable\n");
4350 			xfer_mask &= ~(0xF8 << ATA_SHIFT_UDMA);
4351 		}
4352 
4353 	ata_unpack_xfermask(xfer_mask, &dev->pio_mask,
4354 			    &dev->mwdma_mask, &dev->udma_mask);
4355 }
4356 
4357 /**
4358  *	ata_dev_set_xfermode - Issue SET FEATURES - XFER MODE command
4359  *	@dev: Device to which command will be sent
4360  *
4361  *	Issue SET FEATURES - XFER MODE command to device @dev
4362  *	on port @ap.
4363  *
4364  *	LOCKING:
4365  *	PCI/etc. bus probe sem.
4366  *
4367  *	RETURNS:
4368  *	0 on success, AC_ERR_* mask otherwise.
4369  */
4370 
4371 static unsigned int ata_dev_set_xfermode(struct ata_device *dev)
4372 {
4373 	struct ata_taskfile tf;
4374 	unsigned int err_mask;
4375 
4376 	/* set up set-features taskfile */
4377 	DPRINTK("set features - xfer mode\n");
4378 
4379 	/* Some controllers and ATAPI devices show flaky interrupt
4380 	 * behavior after setting xfer mode.  Use polling instead.
4381 	 */
4382 	ata_tf_init(dev, &tf);
4383 	tf.command = ATA_CMD_SET_FEATURES;
4384 	tf.feature = SETFEATURES_XFER;
4385 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE | ATA_TFLAG_POLLING;
4386 	tf.protocol = ATA_PROT_NODATA;
4387 	/* If we are using IORDY we must send the mode setting command */
4388 	if (ata_pio_need_iordy(dev))
4389 		tf.nsect = dev->xfer_mode;
4390 	/* If the device has IORDY and the controller does not - turn it off */
4391  	else if (ata_id_has_iordy(dev->id))
4392 		tf.nsect = 0x01;
4393 	else /* In the ancient relic department - skip all of this */
4394 		return 0;
4395 
4396 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
4397 
4398 	DPRINTK("EXIT, err_mask=%x\n", err_mask);
4399 	return err_mask;
4400 }
4401 /**
4402  *	ata_dev_set_feature - Issue SET FEATURES - SATA FEATURES
4403  *	@dev: Device to which command will be sent
4404  *	@enable: Whether to enable or disable the feature
4405  *	@feature: The sector count represents the feature to set
4406  *
4407  *	Issue SET FEATURES - SATA FEATURES command to device @dev
4408  *	on port @ap with sector count
4409  *
4410  *	LOCKING:
4411  *	PCI/etc. bus probe sem.
4412  *
4413  *	RETURNS:
4414  *	0 on success, AC_ERR_* mask otherwise.
4415  */
4416 static unsigned int ata_dev_set_feature(struct ata_device *dev, u8 enable,
4417 					u8 feature)
4418 {
4419 	struct ata_taskfile tf;
4420 	unsigned int err_mask;
4421 
4422 	/* set up set-features taskfile */
4423 	DPRINTK("set features - SATA features\n");
4424 
4425 	ata_tf_init(dev, &tf);
4426 	tf.command = ATA_CMD_SET_FEATURES;
4427 	tf.feature = enable;
4428 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
4429 	tf.protocol = ATA_PROT_NODATA;
4430 	tf.nsect = feature;
4431 
4432 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
4433 
4434 	DPRINTK("EXIT, err_mask=%x\n", err_mask);
4435 	return err_mask;
4436 }
4437 
4438 /**
4439  *	ata_dev_init_params - Issue INIT DEV PARAMS command
4440  *	@dev: Device to which command will be sent
4441  *	@heads: Number of heads (taskfile parameter)
4442  *	@sectors: Number of sectors (taskfile parameter)
4443  *
4444  *	LOCKING:
4445  *	Kernel thread context (may sleep)
4446  *
4447  *	RETURNS:
4448  *	0 on success, AC_ERR_* mask otherwise.
4449  */
4450 static unsigned int ata_dev_init_params(struct ata_device *dev,
4451 					u16 heads, u16 sectors)
4452 {
4453 	struct ata_taskfile tf;
4454 	unsigned int err_mask;
4455 
4456 	/* Number of sectors per track 1-255. Number of heads 1-16 */
4457 	if (sectors < 1 || sectors > 255 || heads < 1 || heads > 16)
4458 		return AC_ERR_INVALID;
4459 
4460 	/* set up init dev params taskfile */
4461 	DPRINTK("init dev params \n");
4462 
4463 	ata_tf_init(dev, &tf);
4464 	tf.command = ATA_CMD_INIT_DEV_PARAMS;
4465 	tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
4466 	tf.protocol = ATA_PROT_NODATA;
4467 	tf.nsect = sectors;
4468 	tf.device |= (heads - 1) & 0x0f; /* max head = num. of heads - 1 */
4469 
4470 	err_mask = ata_exec_internal(dev, &tf, NULL, DMA_NONE, NULL, 0, 0);
4471 	/* A clean abort indicates an original or just out of spec drive
4472 	   and we should continue as we issue the setup based on the
4473 	   drive reported working geometry */
4474 	if (err_mask == AC_ERR_DEV && (tf.feature & ATA_ABORTED))
4475 		err_mask = 0;
4476 
4477 	DPRINTK("EXIT, err_mask=%x\n", err_mask);
4478 	return err_mask;
4479 }
4480 
4481 /**
4482  *	ata_sg_clean - Unmap DMA memory associated with command
4483  *	@qc: Command containing DMA memory to be released
4484  *
4485  *	Unmap all mapped DMA memory associated with this command.
4486  *
4487  *	LOCKING:
4488  *	spin_lock_irqsave(host lock)
4489  */
4490 void ata_sg_clean(struct ata_queued_cmd *qc)
4491 {
4492 	struct ata_port *ap = qc->ap;
4493 	struct scatterlist *sg = qc->sg;
4494 	int dir = qc->dma_dir;
4495 	void *pad_buf = NULL;
4496 
4497 	WARN_ON(sg == NULL);
4498 
4499 	VPRINTK("unmapping %u sg elements\n", qc->mapped_n_elem);
4500 
4501 	/* if we padded the buffer out to 32-bit bound, and data
4502 	 * xfer direction is from-device, we must copy from the
4503 	 * pad buffer back into the supplied buffer
4504 	 */
4505 	if (qc->pad_len && !(qc->tf.flags & ATA_TFLAG_WRITE))
4506 		pad_buf = ap->pad + (qc->tag * ATA_DMA_PAD_SZ);
4507 
4508 	if (qc->mapped_n_elem)
4509 		dma_unmap_sg(ap->dev, sg, qc->mapped_n_elem, dir);
4510 	/* restore last sg */
4511 	if (qc->last_sg)
4512 		*qc->last_sg = qc->saved_last_sg;
4513 	if (pad_buf) {
4514 		struct scatterlist *psg = &qc->extra_sg[1];
4515 		void *addr = kmap_atomic(sg_page(psg), KM_IRQ0);
4516 		memcpy(addr + psg->offset, pad_buf, qc->pad_len);
4517 		kunmap_atomic(addr, KM_IRQ0);
4518 	}
4519 
4520 	qc->flags &= ~ATA_QCFLAG_DMAMAP;
4521 	qc->sg = NULL;
4522 }
4523 
4524 /**
4525  *	ata_fill_sg - Fill PCI IDE PRD table
4526  *	@qc: Metadata associated with taskfile to be transferred
4527  *
4528  *	Fill PCI IDE PRD (scatter-gather) table with segments
4529  *	associated with the current disk command.
4530  *
4531  *	LOCKING:
4532  *	spin_lock_irqsave(host lock)
4533  *
4534  */
4535 static void ata_fill_sg(struct ata_queued_cmd *qc)
4536 {
4537 	struct ata_port *ap = qc->ap;
4538 	struct scatterlist *sg;
4539 	unsigned int si, pi;
4540 
4541 	pi = 0;
4542 	for_each_sg(qc->sg, sg, qc->n_elem, si) {
4543 		u32 addr, offset;
4544 		u32 sg_len, len;
4545 
4546 		/* determine if physical DMA addr spans 64K boundary.
4547 		 * Note h/w doesn't support 64-bit, so we unconditionally
4548 		 * truncate dma_addr_t to u32.
4549 		 */
4550 		addr = (u32) sg_dma_address(sg);
4551 		sg_len = sg_dma_len(sg);
4552 
4553 		while (sg_len) {
4554 			offset = addr & 0xffff;
4555 			len = sg_len;
4556 			if ((offset + sg_len) > 0x10000)
4557 				len = 0x10000 - offset;
4558 
4559 			ap->prd[pi].addr = cpu_to_le32(addr);
4560 			ap->prd[pi].flags_len = cpu_to_le32(len & 0xffff);
4561 			VPRINTK("PRD[%u] = (0x%X, 0x%X)\n", pi, addr, len);
4562 
4563 			pi++;
4564 			sg_len -= len;
4565 			addr += len;
4566 		}
4567 	}
4568 
4569 	ap->prd[pi - 1].flags_len |= cpu_to_le32(ATA_PRD_EOT);
4570 }
4571 
4572 /**
4573  *	ata_fill_sg_dumb - Fill PCI IDE PRD table
4574  *	@qc: Metadata associated with taskfile to be transferred
4575  *
4576  *	Fill PCI IDE PRD (scatter-gather) table with segments
4577  *	associated with the current disk command. Perform the fill
4578  *	so that we avoid writing any length 64K records for
4579  *	controllers that don't follow the spec.
4580  *
4581  *	LOCKING:
4582  *	spin_lock_irqsave(host lock)
4583  *
4584  */
4585 static void ata_fill_sg_dumb(struct ata_queued_cmd *qc)
4586 {
4587 	struct ata_port *ap = qc->ap;
4588 	struct scatterlist *sg;
4589 	unsigned int si, pi;
4590 
4591 	pi = 0;
4592 	for_each_sg(qc->sg, sg, qc->n_elem, si) {
4593 		u32 addr, offset;
4594 		u32 sg_len, len, blen;
4595 
4596 		/* determine if physical DMA addr spans 64K boundary.
4597 		 * Note h/w doesn't support 64-bit, so we unconditionally
4598 		 * truncate dma_addr_t to u32.
4599 		 */
4600 		addr = (u32) sg_dma_address(sg);
4601 		sg_len = sg_dma_len(sg);
4602 
4603 		while (sg_len) {
4604 			offset = addr & 0xffff;
4605 			len = sg_len;
4606 			if ((offset + sg_len) > 0x10000)
4607 				len = 0x10000 - offset;
4608 
4609 			blen = len & 0xffff;
4610 			ap->prd[pi].addr = cpu_to_le32(addr);
4611 			if (blen == 0) {
4612 			   /* Some PATA chipsets like the CS5530 can't
4613 			      cope with 0x0000 meaning 64K as the spec says */
4614 				ap->prd[pi].flags_len = cpu_to_le32(0x8000);
4615 				blen = 0x8000;
4616 				ap->prd[++pi].addr = cpu_to_le32(addr + 0x8000);
4617 			}
4618 			ap->prd[pi].flags_len = cpu_to_le32(blen);
4619 			VPRINTK("PRD[%u] = (0x%X, 0x%X)\n", pi, addr, len);
4620 
4621 			pi++;
4622 			sg_len -= len;
4623 			addr += len;
4624 		}
4625 	}
4626 
4627 	ap->prd[pi - 1].flags_len |= cpu_to_le32(ATA_PRD_EOT);
4628 }
4629 
4630 /**
4631  *	ata_check_atapi_dma - Check whether ATAPI DMA can be supported
4632  *	@qc: Metadata associated with taskfile to check
4633  *
4634  *	Allow low-level driver to filter ATA PACKET commands, returning
4635  *	a status indicating whether or not it is OK to use DMA for the
4636  *	supplied PACKET command.
4637  *
4638  *	LOCKING:
4639  *	spin_lock_irqsave(host lock)
4640  *
4641  *	RETURNS: 0 when ATAPI DMA can be used
4642  *               nonzero otherwise
4643  */
4644 int ata_check_atapi_dma(struct ata_queued_cmd *qc)
4645 {
4646 	struct ata_port *ap = qc->ap;
4647 
4648 	/* Don't allow DMA if it isn't multiple of 16 bytes.  Quite a
4649 	 * few ATAPI devices choke on such DMA requests.
4650 	 */
4651 	if (unlikely(qc->nbytes & 15))
4652 		return 1;
4653 
4654 	if (ap->ops->check_atapi_dma)
4655 		return ap->ops->check_atapi_dma(qc);
4656 
4657 	return 0;
4658 }
4659 
4660 /**
4661  *	atapi_qc_may_overflow - Check whether data transfer may overflow
4662  *	@qc: ATA command in question
4663  *
4664  *	ATAPI commands which transfer variable length data to host
4665  *	might overflow due to application error or hardare bug.  This
4666  *	function checks whether overflow should be drained and ignored
4667  *	for @qc.
4668  *
4669  *	LOCKING:
4670  *	None.
4671  *
4672  *	RETURNS:
4673  *	1 if @qc may overflow; otherwise, 0.
4674  */
4675 static int atapi_qc_may_overflow(struct ata_queued_cmd *qc)
4676 {
4677 	if (qc->tf.protocol != ATAPI_PROT_PIO &&
4678 	    qc->tf.protocol != ATAPI_PROT_DMA)
4679 		return 0;
4680 
4681 	if (qc->tf.flags & ATA_TFLAG_WRITE)
4682 		return 0;
4683 
4684 	switch (qc->cdb[0]) {
4685 	case READ_10:
4686 	case READ_12:
4687 	case WRITE_10:
4688 	case WRITE_12:
4689 	case GPCMD_READ_CD:
4690 	case GPCMD_READ_CD_MSF:
4691 		return 0;
4692 	}
4693 
4694 	return 1;
4695 }
4696 
4697 /**
4698  *	ata_std_qc_defer - Check whether a qc needs to be deferred
4699  *	@qc: ATA command in question
4700  *
4701  *	Non-NCQ commands cannot run with any other command, NCQ or
4702  *	not.  As upper layer only knows the queue depth, we are
4703  *	responsible for maintaining exclusion.  This function checks
4704  *	whether a new command @qc can be issued.
4705  *
4706  *	LOCKING:
4707  *	spin_lock_irqsave(host lock)
4708  *
4709  *	RETURNS:
4710  *	ATA_DEFER_* if deferring is needed, 0 otherwise.
4711  */
4712 int ata_std_qc_defer(struct ata_queued_cmd *qc)
4713 {
4714 	struct ata_link *link = qc->dev->link;
4715 
4716 	if (qc->tf.protocol == ATA_PROT_NCQ) {
4717 		if (!ata_tag_valid(link->active_tag))
4718 			return 0;
4719 	} else {
4720 		if (!ata_tag_valid(link->active_tag) && !link->sactive)
4721 			return 0;
4722 	}
4723 
4724 	return ATA_DEFER_LINK;
4725 }
4726 
4727 /**
4728  *	ata_qc_prep - Prepare taskfile for submission
4729  *	@qc: Metadata associated with taskfile to be prepared
4730  *
4731  *	Prepare ATA taskfile for submission.
4732  *
4733  *	LOCKING:
4734  *	spin_lock_irqsave(host lock)
4735  */
4736 void ata_qc_prep(struct ata_queued_cmd *qc)
4737 {
4738 	if (!(qc->flags & ATA_QCFLAG_DMAMAP))
4739 		return;
4740 
4741 	ata_fill_sg(qc);
4742 }
4743 
4744 /**
4745  *	ata_dumb_qc_prep - Prepare taskfile for submission
4746  *	@qc: Metadata associated with taskfile to be prepared
4747  *
4748  *	Prepare ATA taskfile for submission.
4749  *
4750  *	LOCKING:
4751  *	spin_lock_irqsave(host lock)
4752  */
4753 void ata_dumb_qc_prep(struct ata_queued_cmd *qc)
4754 {
4755 	if (!(qc->flags & ATA_QCFLAG_DMAMAP))
4756 		return;
4757 
4758 	ata_fill_sg_dumb(qc);
4759 }
4760 
4761 void ata_noop_qc_prep(struct ata_queued_cmd *qc) { }
4762 
4763 /**
4764  *	ata_sg_init - Associate command with scatter-gather table.
4765  *	@qc: Command to be associated
4766  *	@sg: Scatter-gather table.
4767  *	@n_elem: Number of elements in s/g table.
4768  *
4769  *	Initialize the data-related elements of queued_cmd @qc
4770  *	to point to a scatter-gather table @sg, containing @n_elem
4771  *	elements.
4772  *
4773  *	LOCKING:
4774  *	spin_lock_irqsave(host lock)
4775  */
4776 void ata_sg_init(struct ata_queued_cmd *qc, struct scatterlist *sg,
4777 		 unsigned int n_elem)
4778 {
4779 	qc->sg = sg;
4780 	qc->n_elem = n_elem;
4781 	qc->cursg = qc->sg;
4782 }
4783 
4784 static unsigned int ata_sg_setup_extra(struct ata_queued_cmd *qc,
4785 				       unsigned int *n_elem_extra,
4786 				       unsigned int *nbytes_extra)
4787 {
4788 	struct ata_port *ap = qc->ap;
4789 	unsigned int n_elem = qc->n_elem;
4790 	struct scatterlist *lsg, *copy_lsg = NULL, *tsg = NULL, *esg = NULL;
4791 
4792 	*n_elem_extra = 0;
4793 	*nbytes_extra = 0;
4794 
4795 	/* needs padding? */
4796 	qc->pad_len = qc->nbytes & 3;
4797 
4798 	if (likely(!qc->pad_len))
4799 		return n_elem;
4800 
4801 	/* locate last sg and save it */
4802 	lsg = sg_last(qc->sg, n_elem);
4803 	qc->last_sg = lsg;
4804 	qc->saved_last_sg = *lsg;
4805 
4806 	sg_init_table(qc->extra_sg, ARRAY_SIZE(qc->extra_sg));
4807 
4808 	if (qc->pad_len) {
4809 		struct scatterlist *psg = &qc->extra_sg[1];
4810 		void *pad_buf = ap->pad + (qc->tag * ATA_DMA_PAD_SZ);
4811 		unsigned int offset;
4812 
4813 		WARN_ON(qc->dev->class != ATA_DEV_ATAPI);
4814 
4815 		memset(pad_buf, 0, ATA_DMA_PAD_SZ);
4816 
4817 		/* psg->page/offset are used to copy to-be-written
4818 		 * data in this function or read data in ata_sg_clean.
4819 		 */
4820 		offset = lsg->offset + lsg->length - qc->pad_len;
4821 		sg_set_page(psg, nth_page(sg_page(lsg), offset >> PAGE_SHIFT),
4822 			    qc->pad_len, offset_in_page(offset));
4823 
4824 		if (qc->tf.flags & ATA_TFLAG_WRITE) {
4825 			void *addr = kmap_atomic(sg_page(psg), KM_IRQ0);
4826 			memcpy(pad_buf, addr + psg->offset, qc->pad_len);
4827 			kunmap_atomic(addr, KM_IRQ0);
4828 		}
4829 
4830 		sg_dma_address(psg) = ap->pad_dma + (qc->tag * ATA_DMA_PAD_SZ);
4831 		sg_dma_len(psg) = ATA_DMA_PAD_SZ;
4832 
4833 		/* Trim the last sg entry and chain the original and
4834 		 * padding sg lists.
4835 		 *
4836 		 * Because chaining consumes one sg entry, one extra
4837 		 * sg entry is allocated and the last sg entry is
4838 		 * copied to it if the length isn't zero after padded
4839 		 * amount is removed.
4840 		 *
4841 		 * If the last sg entry is completely replaced by
4842 		 * padding sg entry, the first sg entry is skipped
4843 		 * while chaining.
4844 		 */
4845 		lsg->length -= qc->pad_len;
4846 		if (lsg->length) {
4847 			copy_lsg = &qc->extra_sg[0];
4848 			tsg = &qc->extra_sg[0];
4849 		} else {
4850 			n_elem--;
4851 			tsg = &qc->extra_sg[1];
4852 		}
4853 
4854 		esg = &qc->extra_sg[1];
4855 
4856 		(*n_elem_extra)++;
4857 		(*nbytes_extra) += 4 - qc->pad_len;
4858 	}
4859 
4860 	if (copy_lsg)
4861 		sg_set_page(copy_lsg, sg_page(lsg), lsg->length, lsg->offset);
4862 
4863 	sg_chain(lsg, 1, tsg);
4864 	sg_mark_end(esg);
4865 
4866 	/* sglist can't start with chaining sg entry, fast forward */
4867 	if (qc->sg == lsg) {
4868 		qc->sg = tsg;
4869 		qc->cursg = tsg;
4870 	}
4871 
4872 	return n_elem;
4873 }
4874 
4875 /**
4876  *	ata_sg_setup - DMA-map the scatter-gather table associated with a command.
4877  *	@qc: Command with scatter-gather table to be mapped.
4878  *
4879  *	DMA-map the scatter-gather table associated with queued_cmd @qc.
4880  *
4881  *	LOCKING:
4882  *	spin_lock_irqsave(host lock)
4883  *
4884  *	RETURNS:
4885  *	Zero on success, negative on error.
4886  *
4887  */
4888 static int ata_sg_setup(struct ata_queued_cmd *qc)
4889 {
4890 	struct ata_port *ap = qc->ap;
4891 	unsigned int n_elem, n_elem_extra, nbytes_extra;
4892 
4893 	VPRINTK("ENTER, ata%u\n", ap->print_id);
4894 
4895 	n_elem = ata_sg_setup_extra(qc, &n_elem_extra, &nbytes_extra);
4896 
4897 	if (n_elem) {
4898 		n_elem = dma_map_sg(ap->dev, qc->sg, n_elem, qc->dma_dir);
4899 		if (n_elem < 1) {
4900 			/* restore last sg */
4901 			if (qc->last_sg)
4902 				*qc->last_sg = qc->saved_last_sg;
4903 			return -1;
4904 		}
4905 		DPRINTK("%d sg elements mapped\n", n_elem);
4906 	}
4907 
4908 	qc->n_elem = qc->mapped_n_elem = n_elem;
4909 	qc->n_elem += n_elem_extra;
4910 	qc->nbytes += nbytes_extra;
4911 	qc->flags |= ATA_QCFLAG_DMAMAP;
4912 
4913 	return 0;
4914 }
4915 
4916 /**
4917  *	swap_buf_le16 - swap halves of 16-bit words in place
4918  *	@buf:  Buffer to swap
4919  *	@buf_words:  Number of 16-bit words in buffer.
4920  *
4921  *	Swap halves of 16-bit words if needed to convert from
4922  *	little-endian byte order to native cpu byte order, or
4923  *	vice-versa.
4924  *
4925  *	LOCKING:
4926  *	Inherited from caller.
4927  */
4928 void swap_buf_le16(u16 *buf, unsigned int buf_words)
4929 {
4930 #ifdef __BIG_ENDIAN
4931 	unsigned int i;
4932 
4933 	for (i = 0; i < buf_words; i++)
4934 		buf[i] = le16_to_cpu(buf[i]);
4935 #endif /* __BIG_ENDIAN */
4936 }
4937 
4938 /**
4939  *	ata_data_xfer - Transfer data by PIO
4940  *	@dev: device to target
4941  *	@buf: data buffer
4942  *	@buflen: buffer length
4943  *	@rw: read/write
4944  *
4945  *	Transfer data from/to the device data register by PIO.
4946  *
4947  *	LOCKING:
4948  *	Inherited from caller.
4949  *
4950  *	RETURNS:
4951  *	Bytes consumed.
4952  */
4953 unsigned int ata_data_xfer(struct ata_device *dev, unsigned char *buf,
4954 			   unsigned int buflen, int rw)
4955 {
4956 	struct ata_port *ap = dev->link->ap;
4957 	void __iomem *data_addr = ap->ioaddr.data_addr;
4958 	unsigned int words = buflen >> 1;
4959 
4960 	/* Transfer multiple of 2 bytes */
4961 	if (rw == READ)
4962 		ioread16_rep(data_addr, buf, words);
4963 	else
4964 		iowrite16_rep(data_addr, buf, words);
4965 
4966 	/* Transfer trailing 1 byte, if any. */
4967 	if (unlikely(buflen & 0x01)) {
4968 		__le16 align_buf[1] = { 0 };
4969 		unsigned char *trailing_buf = buf + buflen - 1;
4970 
4971 		if (rw == READ) {
4972 			align_buf[0] = cpu_to_le16(ioread16(data_addr));
4973 			memcpy(trailing_buf, align_buf, 1);
4974 		} else {
4975 			memcpy(align_buf, trailing_buf, 1);
4976 			iowrite16(le16_to_cpu(align_buf[0]), data_addr);
4977 		}
4978 		words++;
4979 	}
4980 
4981 	return words << 1;
4982 }
4983 
4984 /**
4985  *	ata_data_xfer_noirq - Transfer data by PIO
4986  *	@dev: device to target
4987  *	@buf: data buffer
4988  *	@buflen: buffer length
4989  *	@rw: read/write
4990  *
4991  *	Transfer data from/to the device data register by PIO. Do the
4992  *	transfer with interrupts disabled.
4993  *
4994  *	LOCKING:
4995  *	Inherited from caller.
4996  *
4997  *	RETURNS:
4998  *	Bytes consumed.
4999  */
5000 unsigned int ata_data_xfer_noirq(struct ata_device *dev, unsigned char *buf,
5001 				 unsigned int buflen, int rw)
5002 {
5003 	unsigned long flags;
5004 	unsigned int consumed;
5005 
5006 	local_irq_save(flags);
5007 	consumed = ata_data_xfer(dev, buf, buflen, rw);
5008 	local_irq_restore(flags);
5009 
5010 	return consumed;
5011 }
5012 
5013 
5014 /**
5015  *	ata_pio_sector - Transfer a sector of data.
5016  *	@qc: Command on going
5017  *
5018  *	Transfer qc->sect_size bytes of data from/to the ATA device.
5019  *
5020  *	LOCKING:
5021  *	Inherited from caller.
5022  */
5023 
5024 static void ata_pio_sector(struct ata_queued_cmd *qc)
5025 {
5026 	int do_write = (qc->tf.flags & ATA_TFLAG_WRITE);
5027 	struct ata_port *ap = qc->ap;
5028 	struct page *page;
5029 	unsigned int offset;
5030 	unsigned char *buf;
5031 
5032 	if (qc->curbytes == qc->nbytes - qc->sect_size)
5033 		ap->hsm_task_state = HSM_ST_LAST;
5034 
5035 	page = sg_page(qc->cursg);
5036 	offset = qc->cursg->offset + qc->cursg_ofs;
5037 
5038 	/* get the current page and offset */
5039 	page = nth_page(page, (offset >> PAGE_SHIFT));
5040 	offset %= PAGE_SIZE;
5041 
5042 	DPRINTK("data %s\n", qc->tf.flags & ATA_TFLAG_WRITE ? "write" : "read");
5043 
5044 	if (PageHighMem(page)) {
5045 		unsigned long flags;
5046 
5047 		/* FIXME: use a bounce buffer */
5048 		local_irq_save(flags);
5049 		buf = kmap_atomic(page, KM_IRQ0);
5050 
5051 		/* do the actual data transfer */
5052 		ap->ops->data_xfer(qc->dev, buf + offset, qc->sect_size, do_write);
5053 
5054 		kunmap_atomic(buf, KM_IRQ0);
5055 		local_irq_restore(flags);
5056 	} else {
5057 		buf = page_address(page);
5058 		ap->ops->data_xfer(qc->dev, buf + offset, qc->sect_size, do_write);
5059 	}
5060 
5061 	qc->curbytes += qc->sect_size;
5062 	qc->cursg_ofs += qc->sect_size;
5063 
5064 	if (qc->cursg_ofs == qc->cursg->length) {
5065 		qc->cursg = sg_next(qc->cursg);
5066 		qc->cursg_ofs = 0;
5067 	}
5068 }
5069 
5070 /**
5071  *	ata_pio_sectors - Transfer one or many sectors.
5072  *	@qc: Command on going
5073  *
5074  *	Transfer one or many sectors of data from/to the
5075  *	ATA device for the DRQ request.
5076  *
5077  *	LOCKING:
5078  *	Inherited from caller.
5079  */
5080 
5081 static void ata_pio_sectors(struct ata_queued_cmd *qc)
5082 {
5083 	if (is_multi_taskfile(&qc->tf)) {
5084 		/* READ/WRITE MULTIPLE */
5085 		unsigned int nsect;
5086 
5087 		WARN_ON(qc->dev->multi_count == 0);
5088 
5089 		nsect = min((qc->nbytes - qc->curbytes) / qc->sect_size,
5090 			    qc->dev->multi_count);
5091 		while (nsect--)
5092 			ata_pio_sector(qc);
5093 	} else
5094 		ata_pio_sector(qc);
5095 
5096 	ata_altstatus(qc->ap); /* flush */
5097 }
5098 
5099 /**
5100  *	atapi_send_cdb - Write CDB bytes to hardware
5101  *	@ap: Port to which ATAPI device is attached.
5102  *	@qc: Taskfile currently active
5103  *
5104  *	When device has indicated its readiness to accept
5105  *	a CDB, this function is called.  Send the CDB.
5106  *
5107  *	LOCKING:
5108  *	caller.
5109  */
5110 
5111 static void atapi_send_cdb(struct ata_port *ap, struct ata_queued_cmd *qc)
5112 {
5113 	/* send SCSI cdb */
5114 	DPRINTK("send cdb\n");
5115 	WARN_ON(qc->dev->cdb_len < 12);
5116 
5117 	ap->ops->data_xfer(qc->dev, qc->cdb, qc->dev->cdb_len, 1);
5118 	ata_altstatus(ap); /* flush */
5119 
5120 	switch (qc->tf.protocol) {
5121 	case ATAPI_PROT_PIO:
5122 		ap->hsm_task_state = HSM_ST;
5123 		break;
5124 	case ATAPI_PROT_NODATA:
5125 		ap->hsm_task_state = HSM_ST_LAST;
5126 		break;
5127 	case ATAPI_PROT_DMA:
5128 		ap->hsm_task_state = HSM_ST_LAST;
5129 		/* initiate bmdma */
5130 		ap->ops->bmdma_start(qc);
5131 		break;
5132 	}
5133 }
5134 
5135 /**
5136  *	__atapi_pio_bytes - Transfer data from/to the ATAPI device.
5137  *	@qc: Command on going
5138  *	@bytes: number of bytes
5139  *
5140  *	Transfer Transfer data from/to the ATAPI device.
5141  *
5142  *	LOCKING:
5143  *	Inherited from caller.
5144  *
5145  */
5146 static int __atapi_pio_bytes(struct ata_queued_cmd *qc, unsigned int bytes)
5147 {
5148 	int do_write = (qc->tf.flags & ATA_TFLAG_WRITE);
5149 	struct ata_port *ap = qc->ap;
5150 	struct ata_eh_info *ehi = &qc->dev->link->eh_info;
5151 	struct scatterlist *sg;
5152 	struct page *page;
5153 	unsigned char *buf;
5154 	unsigned int offset, count;
5155 
5156 next_sg:
5157 	sg = qc->cursg;
5158 	if (unlikely(!sg)) {
5159 		/*
5160 		 * The end of qc->sg is reached and the device expects
5161 		 * more data to transfer. In order not to overrun qc->sg
5162 		 * and fulfill length specified in the byte count register,
5163 		 *    - for read case, discard trailing data from the device
5164 		 *    - for write case, padding zero data to the device
5165 		 */
5166 		u16 pad_buf[1] = { 0 };
5167 		unsigned int i;
5168 
5169 		if (bytes > qc->curbytes - qc->nbytes + ATAPI_MAX_DRAIN) {
5170 			ata_ehi_push_desc(ehi, "too much trailing data "
5171 					  "buf=%u cur=%u bytes=%u",
5172 					  qc->nbytes, qc->curbytes, bytes);
5173 			return -1;
5174 		}
5175 
5176 		 /* overflow is exptected for misc ATAPI commands */
5177 		if (bytes && !atapi_qc_may_overflow(qc))
5178 			ata_dev_printk(qc->dev, KERN_WARNING, "ATAPI %u bytes "
5179 				       "trailing data (cdb=%02x nbytes=%u)\n",
5180 				       bytes, qc->cdb[0], qc->nbytes);
5181 
5182 		for (i = 0; i < (bytes + 1) / 2; i++)
5183 			ap->ops->data_xfer(qc->dev, (unsigned char *)pad_buf, 2, do_write);
5184 
5185 		qc->curbytes += bytes;
5186 
5187 		return 0;
5188 	}
5189 
5190 	page = sg_page(sg);
5191 	offset = sg->offset + qc->cursg_ofs;
5192 
5193 	/* get the current page and offset */
5194 	page = nth_page(page, (offset >> PAGE_SHIFT));
5195 	offset %= PAGE_SIZE;
5196 
5197 	/* don't overrun current sg */
5198 	count = min(sg->length - qc->cursg_ofs, bytes);
5199 
5200 	/* don't cross page boundaries */
5201 	count = min(count, (unsigned int)PAGE_SIZE - offset);
5202 
5203 	DPRINTK("data %s\n", qc->tf.flags & ATA_TFLAG_WRITE ? "write" : "read");
5204 
5205 	if (PageHighMem(page)) {
5206 		unsigned long flags;
5207 
5208 		/* FIXME: use bounce buffer */
5209 		local_irq_save(flags);
5210 		buf = kmap_atomic(page, KM_IRQ0);
5211 
5212 		/* do the actual data transfer */
5213 		ap->ops->data_xfer(qc->dev,  buf + offset, count, do_write);
5214 
5215 		kunmap_atomic(buf, KM_IRQ0);
5216 		local_irq_restore(flags);
5217 	} else {
5218 		buf = page_address(page);
5219 		ap->ops->data_xfer(qc->dev,  buf + offset, count, do_write);
5220 	}
5221 
5222 	bytes -= count;
5223 	if ((count & 1) && bytes)
5224 		bytes--;
5225 	qc->curbytes += count;
5226 	qc->cursg_ofs += count;
5227 
5228 	if (qc->cursg_ofs == sg->length) {
5229 		qc->cursg = sg_next(qc->cursg);
5230 		qc->cursg_ofs = 0;
5231 	}
5232 
5233 	if (bytes)
5234 		goto next_sg;
5235 
5236 	return 0;
5237 }
5238 
5239 /**
5240  *	atapi_pio_bytes - Transfer data from/to the ATAPI device.
5241  *	@qc: Command on going
5242  *
5243  *	Transfer Transfer data from/to the ATAPI device.
5244  *
5245  *	LOCKING:
5246  *	Inherited from caller.
5247  */
5248 
5249 static void atapi_pio_bytes(struct ata_queued_cmd *qc)
5250 {
5251 	struct ata_port *ap = qc->ap;
5252 	struct ata_device *dev = qc->dev;
5253 	unsigned int ireason, bc_lo, bc_hi, bytes;
5254 	int i_write, do_write = (qc->tf.flags & ATA_TFLAG_WRITE) ? 1 : 0;
5255 
5256 	/* Abuse qc->result_tf for temp storage of intermediate TF
5257 	 * here to save some kernel stack usage.
5258 	 * For normal completion, qc->result_tf is not relevant. For
5259 	 * error, qc->result_tf is later overwritten by ata_qc_complete().
5260 	 * So, the correctness of qc->result_tf is not affected.
5261 	 */
5262 	ap->ops->tf_read(ap, &qc->result_tf);
5263 	ireason = qc->result_tf.nsect;
5264 	bc_lo = qc->result_tf.lbam;
5265 	bc_hi = qc->result_tf.lbah;
5266 	bytes = (bc_hi << 8) | bc_lo;
5267 
5268 	/* shall be cleared to zero, indicating xfer of data */
5269 	if (unlikely(ireason & (1 << 0)))
5270 		goto err_out;
5271 
5272 	/* make sure transfer direction matches expected */
5273 	i_write = ((ireason & (1 << 1)) == 0) ? 1 : 0;
5274 	if (unlikely(do_write != i_write))
5275 		goto err_out;
5276 
5277 	if (unlikely(!bytes))
5278 		goto err_out;
5279 
5280 	VPRINTK("ata%u: xfering %d bytes\n", ap->print_id, bytes);
5281 
5282 	if (__atapi_pio_bytes(qc, bytes))
5283 		goto err_out;
5284 	ata_altstatus(ap); /* flush */
5285 
5286 	return;
5287 
5288 err_out:
5289 	ata_dev_printk(dev, KERN_INFO, "ATAPI check failed\n");
5290 	qc->err_mask |= AC_ERR_HSM;
5291 	ap->hsm_task_state = HSM_ST_ERR;
5292 }
5293 
5294 /**
5295  *	ata_hsm_ok_in_wq - Check if the qc can be handled in the workqueue.
5296  *	@ap: the target ata_port
5297  *	@qc: qc on going
5298  *
5299  *	RETURNS:
5300  *	1 if ok in workqueue, 0 otherwise.
5301  */
5302 
5303 static inline int ata_hsm_ok_in_wq(struct ata_port *ap, struct ata_queued_cmd *qc)
5304 {
5305 	if (qc->tf.flags & ATA_TFLAG_POLLING)
5306 		return 1;
5307 
5308 	if (ap->hsm_task_state == HSM_ST_FIRST) {
5309 		if (qc->tf.protocol == ATA_PROT_PIO &&
5310 		    (qc->tf.flags & ATA_TFLAG_WRITE))
5311 		    return 1;
5312 
5313 		if (ata_is_atapi(qc->tf.protocol) &&
5314 		    !(qc->dev->flags & ATA_DFLAG_CDB_INTR))
5315 			return 1;
5316 	}
5317 
5318 	return 0;
5319 }
5320 
5321 /**
5322  *	ata_hsm_qc_complete - finish a qc running on standard HSM
5323  *	@qc: Command to complete
5324  *	@in_wq: 1 if called from workqueue, 0 otherwise
5325  *
5326  *	Finish @qc which is running on standard HSM.
5327  *
5328  *	LOCKING:
5329  *	If @in_wq is zero, spin_lock_irqsave(host lock).
5330  *	Otherwise, none on entry and grabs host lock.
5331  */
5332 static void ata_hsm_qc_complete(struct ata_queued_cmd *qc, int in_wq)
5333 {
5334 	struct ata_port *ap = qc->ap;
5335 	unsigned long flags;
5336 
5337 	if (ap->ops->error_handler) {
5338 		if (in_wq) {
5339 			spin_lock_irqsave(ap->lock, flags);
5340 
5341 			/* EH might have kicked in while host lock is
5342 			 * released.
5343 			 */
5344 			qc = ata_qc_from_tag(ap, qc->tag);
5345 			if (qc) {
5346 				if (likely(!(qc->err_mask & AC_ERR_HSM))) {
5347 					ap->ops->irq_on(ap);
5348 					ata_qc_complete(qc);
5349 				} else
5350 					ata_port_freeze(ap);
5351 			}
5352 
5353 			spin_unlock_irqrestore(ap->lock, flags);
5354 		} else {
5355 			if (likely(!(qc->err_mask & AC_ERR_HSM)))
5356 				ata_qc_complete(qc);
5357 			else
5358 				ata_port_freeze(ap);
5359 		}
5360 	} else {
5361 		if (in_wq) {
5362 			spin_lock_irqsave(ap->lock, flags);
5363 			ap->ops->irq_on(ap);
5364 			ata_qc_complete(qc);
5365 			spin_unlock_irqrestore(ap->lock, flags);
5366 		} else
5367 			ata_qc_complete(qc);
5368 	}
5369 }
5370 
5371 /**
5372  *	ata_hsm_move - move the HSM to the next state.
5373  *	@ap: the target ata_port
5374  *	@qc: qc on going
5375  *	@status: current device status
5376  *	@in_wq: 1 if called from workqueue, 0 otherwise
5377  *
5378  *	RETURNS:
5379  *	1 when poll next status needed, 0 otherwise.
5380  */
5381 int ata_hsm_move(struct ata_port *ap, struct ata_queued_cmd *qc,
5382 		 u8 status, int in_wq)
5383 {
5384 	unsigned long flags = 0;
5385 	int poll_next;
5386 
5387 	WARN_ON((qc->flags & ATA_QCFLAG_ACTIVE) == 0);
5388 
5389 	/* Make sure ata_qc_issue_prot() does not throw things
5390 	 * like DMA polling into the workqueue. Notice that
5391 	 * in_wq is not equivalent to (qc->tf.flags & ATA_TFLAG_POLLING).
5392 	 */
5393 	WARN_ON(in_wq != ata_hsm_ok_in_wq(ap, qc));
5394 
5395 fsm_start:
5396 	DPRINTK("ata%u: protocol %d task_state %d (dev_stat 0x%X)\n",
5397 		ap->print_id, qc->tf.protocol, ap->hsm_task_state, status);
5398 
5399 	switch (ap->hsm_task_state) {
5400 	case HSM_ST_FIRST:
5401 		/* Send first data block or PACKET CDB */
5402 
5403 		/* If polling, we will stay in the work queue after
5404 		 * sending the data. Otherwise, interrupt handler
5405 		 * takes over after sending the data.
5406 		 */
5407 		poll_next = (qc->tf.flags & ATA_TFLAG_POLLING);
5408 
5409 		/* check device status */
5410 		if (unlikely((status & ATA_DRQ) == 0)) {
5411 			/* handle BSY=0, DRQ=0 as error */
5412 			if (likely(status & (ATA_ERR | ATA_DF)))
5413 				/* device stops HSM for abort/error */
5414 				qc->err_mask |= AC_ERR_DEV;
5415 			else
5416 				/* HSM violation. Let EH handle this */
5417 				qc->err_mask |= AC_ERR_HSM;
5418 
5419 			ap->hsm_task_state = HSM_ST_ERR;
5420 			goto fsm_start;
5421 		}
5422 
5423 		/* Device should not ask for data transfer (DRQ=1)
5424 		 * when it finds something wrong.
5425 		 * We ignore DRQ here and stop the HSM by
5426 		 * changing hsm_task_state to HSM_ST_ERR and
5427 		 * let the EH abort the command or reset the device.
5428 		 */
5429 		if (unlikely(status & (ATA_ERR | ATA_DF))) {
5430 			/* Some ATAPI tape drives forget to clear the ERR bit
5431 			 * when doing the next command (mostly request sense).
5432 			 * We ignore ERR here to workaround and proceed sending
5433 			 * the CDB.
5434 			 */
5435 			if (!(qc->dev->horkage & ATA_HORKAGE_STUCK_ERR)) {
5436 				ata_port_printk(ap, KERN_WARNING,
5437 						"DRQ=1 with device error, "
5438 						"dev_stat 0x%X\n", status);
5439 				qc->err_mask |= AC_ERR_HSM;
5440 				ap->hsm_task_state = HSM_ST_ERR;
5441 				goto fsm_start;
5442 			}
5443 		}
5444 
5445 		/* Send the CDB (atapi) or the first data block (ata pio out).
5446 		 * During the state transition, interrupt handler shouldn't
5447 		 * be invoked before the data transfer is complete and
5448 		 * hsm_task_state is changed. Hence, the following locking.
5449 		 */
5450 		if (in_wq)
5451 			spin_lock_irqsave(ap->lock, flags);
5452 
5453 		if (qc->tf.protocol == ATA_PROT_PIO) {
5454 			/* PIO data out protocol.
5455 			 * send first data block.
5456 			 */
5457 
5458 			/* ata_pio_sectors() might change the state
5459 			 * to HSM_ST_LAST. so, the state is changed here
5460 			 * before ata_pio_sectors().
5461 			 */
5462 			ap->hsm_task_state = HSM_ST;
5463 			ata_pio_sectors(qc);
5464 		} else
5465 			/* send CDB */
5466 			atapi_send_cdb(ap, qc);
5467 
5468 		if (in_wq)
5469 			spin_unlock_irqrestore(ap->lock, flags);
5470 
5471 		/* if polling, ata_pio_task() handles the rest.
5472 		 * otherwise, interrupt handler takes over from here.
5473 		 */
5474 		break;
5475 
5476 	case HSM_ST:
5477 		/* complete command or read/write the data register */
5478 		if (qc->tf.protocol == ATAPI_PROT_PIO) {
5479 			/* ATAPI PIO protocol */
5480 			if ((status & ATA_DRQ) == 0) {
5481 				/* No more data to transfer or device error.
5482 				 * Device error will be tagged in HSM_ST_LAST.
5483 				 */
5484 				ap->hsm_task_state = HSM_ST_LAST;
5485 				goto fsm_start;
5486 			}
5487 
5488 			/* Device should not ask for data transfer (DRQ=1)
5489 			 * when it finds something wrong.
5490 			 * We ignore DRQ here and stop the HSM by
5491 			 * changing hsm_task_state to HSM_ST_ERR and
5492 			 * let the EH abort the command or reset the device.
5493 			 */
5494 			if (unlikely(status & (ATA_ERR | ATA_DF))) {
5495 				ata_port_printk(ap, KERN_WARNING, "DRQ=1 with "
5496 						"device error, dev_stat 0x%X\n",
5497 						status);
5498 				qc->err_mask |= AC_ERR_HSM;
5499 				ap->hsm_task_state = HSM_ST_ERR;
5500 				goto fsm_start;
5501 			}
5502 
5503 			atapi_pio_bytes(qc);
5504 
5505 			if (unlikely(ap->hsm_task_state == HSM_ST_ERR))
5506 				/* bad ireason reported by device */
5507 				goto fsm_start;
5508 
5509 		} else {
5510 			/* ATA PIO protocol */
5511 			if (unlikely((status & ATA_DRQ) == 0)) {
5512 				/* handle BSY=0, DRQ=0 as error */
5513 				if (likely(status & (ATA_ERR | ATA_DF)))
5514 					/* device stops HSM for abort/error */
5515 					qc->err_mask |= AC_ERR_DEV;
5516 				else
5517 					/* HSM violation. Let EH handle this.
5518 					 * Phantom devices also trigger this
5519 					 * condition.  Mark hint.
5520 					 */
5521 					qc->err_mask |= AC_ERR_HSM |
5522 							AC_ERR_NODEV_HINT;
5523 
5524 				ap->hsm_task_state = HSM_ST_ERR;
5525 				goto fsm_start;
5526 			}
5527 
5528 			/* For PIO reads, some devices may ask for
5529 			 * data transfer (DRQ=1) alone with ERR=1.
5530 			 * We respect DRQ here and transfer one
5531 			 * block of junk data before changing the
5532 			 * hsm_task_state to HSM_ST_ERR.
5533 			 *
5534 			 * For PIO writes, ERR=1 DRQ=1 doesn't make
5535 			 * sense since the data block has been
5536 			 * transferred to the device.
5537 			 */
5538 			if (unlikely(status & (ATA_ERR | ATA_DF))) {
5539 				/* data might be corrputed */
5540 				qc->err_mask |= AC_ERR_DEV;
5541 
5542 				if (!(qc->tf.flags & ATA_TFLAG_WRITE)) {
5543 					ata_pio_sectors(qc);
5544 					status = ata_wait_idle(ap);
5545 				}
5546 
5547 				if (status & (ATA_BUSY | ATA_DRQ))
5548 					qc->err_mask |= AC_ERR_HSM;
5549 
5550 				/* ata_pio_sectors() might change the
5551 				 * state to HSM_ST_LAST. so, the state
5552 				 * is changed after ata_pio_sectors().
5553 				 */
5554 				ap->hsm_task_state = HSM_ST_ERR;
5555 				goto fsm_start;
5556 			}
5557 
5558 			ata_pio_sectors(qc);
5559 
5560 			if (ap->hsm_task_state == HSM_ST_LAST &&
5561 			    (!(qc->tf.flags & ATA_TFLAG_WRITE))) {
5562 				/* all data read */
5563 				status = ata_wait_idle(ap);
5564 				goto fsm_start;
5565 			}
5566 		}
5567 
5568 		poll_next = 1;
5569 		break;
5570 
5571 	case HSM_ST_LAST:
5572 		if (unlikely(!ata_ok(status))) {
5573 			qc->err_mask |= __ac_err_mask(status);
5574 			ap->hsm_task_state = HSM_ST_ERR;
5575 			goto fsm_start;
5576 		}
5577 
5578 		/* no more data to transfer */
5579 		DPRINTK("ata%u: dev %u command complete, drv_stat 0x%x\n",
5580 			ap->print_id, qc->dev->devno, status);
5581 
5582 		WARN_ON(qc->err_mask);
5583 
5584 		ap->hsm_task_state = HSM_ST_IDLE;
5585 
5586 		/* complete taskfile transaction */
5587 		ata_hsm_qc_complete(qc, in_wq);
5588 
5589 		poll_next = 0;
5590 		break;
5591 
5592 	case HSM_ST_ERR:
5593 		/* make sure qc->err_mask is available to
5594 		 * know what's wrong and recover
5595 		 */
5596 		WARN_ON(qc->err_mask == 0);
5597 
5598 		ap->hsm_task_state = HSM_ST_IDLE;
5599 
5600 		/* complete taskfile transaction */
5601 		ata_hsm_qc_complete(qc, in_wq);
5602 
5603 		poll_next = 0;
5604 		break;
5605 	default:
5606 		poll_next = 0;
5607 		BUG();
5608 	}
5609 
5610 	return poll_next;
5611 }
5612 
5613 static void ata_pio_task(struct work_struct *work)
5614 {
5615 	struct ata_port *ap =
5616 		container_of(work, struct ata_port, port_task.work);
5617 	struct ata_queued_cmd *qc = ap->port_task_data;
5618 	u8 status;
5619 	int poll_next;
5620 
5621 fsm_start:
5622 	WARN_ON(ap->hsm_task_state == HSM_ST_IDLE);
5623 
5624 	/*
5625 	 * This is purely heuristic.  This is a fast path.
5626 	 * Sometimes when we enter, BSY will be cleared in
5627 	 * a chk-status or two.  If not, the drive is probably seeking
5628 	 * or something.  Snooze for a couple msecs, then
5629 	 * chk-status again.  If still busy, queue delayed work.
5630 	 */
5631 	status = ata_busy_wait(ap, ATA_BUSY, 5);
5632 	if (status & ATA_BUSY) {
5633 		msleep(2);
5634 		status = ata_busy_wait(ap, ATA_BUSY, 10);
5635 		if (status & ATA_BUSY) {
5636 			ata_pio_queue_task(ap, qc, ATA_SHORT_PAUSE);
5637 			return;
5638 		}
5639 	}
5640 
5641 	/* move the HSM */
5642 	poll_next = ata_hsm_move(ap, qc, status, 1);
5643 
5644 	/* another command or interrupt handler
5645 	 * may be running at this point.
5646 	 */
5647 	if (poll_next)
5648 		goto fsm_start;
5649 }
5650 
5651 /**
5652  *	ata_qc_new - Request an available ATA command, for queueing
5653  *	@ap: Port associated with device @dev
5654  *	@dev: Device from whom we request an available command structure
5655  *
5656  *	LOCKING:
5657  *	None.
5658  */
5659 
5660 static struct ata_queued_cmd *ata_qc_new(struct ata_port *ap)
5661 {
5662 	struct ata_queued_cmd *qc = NULL;
5663 	unsigned int i;
5664 
5665 	/* no command while frozen */
5666 	if (unlikely(ap->pflags & ATA_PFLAG_FROZEN))
5667 		return NULL;
5668 
5669 	/* the last tag is reserved for internal command. */
5670 	for (i = 0; i < ATA_MAX_QUEUE - 1; i++)
5671 		if (!test_and_set_bit(i, &ap->qc_allocated)) {
5672 			qc = __ata_qc_from_tag(ap, i);
5673 			break;
5674 		}
5675 
5676 	if (qc)
5677 		qc->tag = i;
5678 
5679 	return qc;
5680 }
5681 
5682 /**
5683  *	ata_qc_new_init - Request an available ATA command, and initialize it
5684  *	@dev: Device from whom we request an available command structure
5685  *
5686  *	LOCKING:
5687  *	None.
5688  */
5689 
5690 struct ata_queued_cmd *ata_qc_new_init(struct ata_device *dev)
5691 {
5692 	struct ata_port *ap = dev->link->ap;
5693 	struct ata_queued_cmd *qc;
5694 
5695 	qc = ata_qc_new(ap);
5696 	if (qc) {
5697 		qc->scsicmd = NULL;
5698 		qc->ap = ap;
5699 		qc->dev = dev;
5700 
5701 		ata_qc_reinit(qc);
5702 	}
5703 
5704 	return qc;
5705 }
5706 
5707 /**
5708  *	ata_qc_free - free unused ata_queued_cmd
5709  *	@qc: Command to complete
5710  *
5711  *	Designed to free unused ata_queued_cmd object
5712  *	in case something prevents using it.
5713  *
5714  *	LOCKING:
5715  *	spin_lock_irqsave(host lock)
5716  */
5717 void ata_qc_free(struct ata_queued_cmd *qc)
5718 {
5719 	struct ata_port *ap = qc->ap;
5720 	unsigned int tag;
5721 
5722 	WARN_ON(qc == NULL);	/* ata_qc_from_tag _might_ return NULL */
5723 
5724 	qc->flags = 0;
5725 	tag = qc->tag;
5726 	if (likely(ata_tag_valid(tag))) {
5727 		qc->tag = ATA_TAG_POISON;
5728 		clear_bit(tag, &ap->qc_allocated);
5729 	}
5730 }
5731 
5732 void __ata_qc_complete(struct ata_queued_cmd *qc)
5733 {
5734 	struct ata_port *ap = qc->ap;
5735 	struct ata_link *link = qc->dev->link;
5736 
5737 	WARN_ON(qc == NULL);	/* ata_qc_from_tag _might_ return NULL */
5738 	WARN_ON(!(qc->flags & ATA_QCFLAG_ACTIVE));
5739 
5740 	if (likely(qc->flags & ATA_QCFLAG_DMAMAP))
5741 		ata_sg_clean(qc);
5742 
5743 	/* command should be marked inactive atomically with qc completion */
5744 	if (qc->tf.protocol == ATA_PROT_NCQ) {
5745 		link->sactive &= ~(1 << qc->tag);
5746 		if (!link->sactive)
5747 			ap->nr_active_links--;
5748 	} else {
5749 		link->active_tag = ATA_TAG_POISON;
5750 		ap->nr_active_links--;
5751 	}
5752 
5753 	/* clear exclusive status */
5754 	if (unlikely(qc->flags & ATA_QCFLAG_CLEAR_EXCL &&
5755 		     ap->excl_link == link))
5756 		ap->excl_link = NULL;
5757 
5758 	/* atapi: mark qc as inactive to prevent the interrupt handler
5759 	 * from completing the command twice later, before the error handler
5760 	 * is called. (when rc != 0 and atapi request sense is needed)
5761 	 */
5762 	qc->flags &= ~ATA_QCFLAG_ACTIVE;
5763 	ap->qc_active &= ~(1 << qc->tag);
5764 
5765 	/* call completion callback */
5766 	qc->complete_fn(qc);
5767 }
5768 
5769 static void fill_result_tf(struct ata_queued_cmd *qc)
5770 {
5771 	struct ata_port *ap = qc->ap;
5772 
5773 	qc->result_tf.flags = qc->tf.flags;
5774 	ap->ops->tf_read(ap, &qc->result_tf);
5775 }
5776 
5777 static void ata_verify_xfer(struct ata_queued_cmd *qc)
5778 {
5779 	struct ata_device *dev = qc->dev;
5780 
5781 	if (ata_tag_internal(qc->tag))
5782 		return;
5783 
5784 	if (ata_is_nodata(qc->tf.protocol))
5785 		return;
5786 
5787 	if ((dev->mwdma_mask || dev->udma_mask) && ata_is_pio(qc->tf.protocol))
5788 		return;
5789 
5790 	dev->flags &= ~ATA_DFLAG_DUBIOUS_XFER;
5791 }
5792 
5793 /**
5794  *	ata_qc_complete - Complete an active ATA command
5795  *	@qc: Command to complete
5796  *	@err_mask: ATA Status register contents
5797  *
5798  *	Indicate to the mid and upper layers that an ATA
5799  *	command has completed, with either an ok or not-ok status.
5800  *
5801  *	LOCKING:
5802  *	spin_lock_irqsave(host lock)
5803  */
5804 void ata_qc_complete(struct ata_queued_cmd *qc)
5805 {
5806 	struct ata_port *ap = qc->ap;
5807 
5808 	/* XXX: New EH and old EH use different mechanisms to
5809 	 * synchronize EH with regular execution path.
5810 	 *
5811 	 * In new EH, a failed qc is marked with ATA_QCFLAG_FAILED.
5812 	 * Normal execution path is responsible for not accessing a
5813 	 * failed qc.  libata core enforces the rule by returning NULL
5814 	 * from ata_qc_from_tag() for failed qcs.
5815 	 *
5816 	 * Old EH depends on ata_qc_complete() nullifying completion
5817 	 * requests if ATA_QCFLAG_EH_SCHEDULED is set.  Old EH does
5818 	 * not synchronize with interrupt handler.  Only PIO task is
5819 	 * taken care of.
5820 	 */
5821 	if (ap->ops->error_handler) {
5822 		struct ata_device *dev = qc->dev;
5823 		struct ata_eh_info *ehi = &dev->link->eh_info;
5824 
5825 		WARN_ON(ap->pflags & ATA_PFLAG_FROZEN);
5826 
5827 		if (unlikely(qc->err_mask))
5828 			qc->flags |= ATA_QCFLAG_FAILED;
5829 
5830 		if (unlikely(qc->flags & ATA_QCFLAG_FAILED)) {
5831 			if (!ata_tag_internal(qc->tag)) {
5832 				/* always fill result TF for failed qc */
5833 				fill_result_tf(qc);
5834 				ata_qc_schedule_eh(qc);
5835 				return;
5836 			}
5837 		}
5838 
5839 		/* read result TF if requested */
5840 		if (qc->flags & ATA_QCFLAG_RESULT_TF)
5841 			fill_result_tf(qc);
5842 
5843 		/* Some commands need post-processing after successful
5844 		 * completion.
5845 		 */
5846 		switch (qc->tf.command) {
5847 		case ATA_CMD_SET_FEATURES:
5848 			if (qc->tf.feature != SETFEATURES_WC_ON &&
5849 			    qc->tf.feature != SETFEATURES_WC_OFF)
5850 				break;
5851 			/* fall through */
5852 		case ATA_CMD_INIT_DEV_PARAMS: /* CHS translation changed */
5853 		case ATA_CMD_SET_MULTI: /* multi_count changed */
5854 			/* revalidate device */
5855 			ehi->dev_action[dev->devno] |= ATA_EH_REVALIDATE;
5856 			ata_port_schedule_eh(ap);
5857 			break;
5858 
5859 		case ATA_CMD_SLEEP:
5860 			dev->flags |= ATA_DFLAG_SLEEPING;
5861 			break;
5862 		}
5863 
5864 		if (unlikely(dev->flags & ATA_DFLAG_DUBIOUS_XFER))
5865 			ata_verify_xfer(qc);
5866 
5867 		__ata_qc_complete(qc);
5868 	} else {
5869 		if (qc->flags & ATA_QCFLAG_EH_SCHEDULED)
5870 			return;
5871 
5872 		/* read result TF if failed or requested */
5873 		if (qc->err_mask || qc->flags & ATA_QCFLAG_RESULT_TF)
5874 			fill_result_tf(qc);
5875 
5876 		__ata_qc_complete(qc);
5877 	}
5878 }
5879 
5880 /**
5881  *	ata_qc_complete_multiple - Complete multiple qcs successfully
5882  *	@ap: port in question
5883  *	@qc_active: new qc_active mask
5884  *	@finish_qc: LLDD callback invoked before completing a qc
5885  *
5886  *	Complete in-flight commands.  This functions is meant to be
5887  *	called from low-level driver's interrupt routine to complete
5888  *	requests normally.  ap->qc_active and @qc_active is compared
5889  *	and commands are completed accordingly.
5890  *
5891  *	LOCKING:
5892  *	spin_lock_irqsave(host lock)
5893  *
5894  *	RETURNS:
5895  *	Number of completed commands on success, -errno otherwise.
5896  */
5897 int ata_qc_complete_multiple(struct ata_port *ap, u32 qc_active,
5898 			     void (*finish_qc)(struct ata_queued_cmd *))
5899 {
5900 	int nr_done = 0;
5901 	u32 done_mask;
5902 	int i;
5903 
5904 	done_mask = ap->qc_active ^ qc_active;
5905 
5906 	if (unlikely(done_mask & qc_active)) {
5907 		ata_port_printk(ap, KERN_ERR, "illegal qc_active transition "
5908 				"(%08x->%08x)\n", ap->qc_active, qc_active);
5909 		return -EINVAL;
5910 	}
5911 
5912 	for (i = 0; i < ATA_MAX_QUEUE; i++) {
5913 		struct ata_queued_cmd *qc;
5914 
5915 		if (!(done_mask & (1 << i)))
5916 			continue;
5917 
5918 		if ((qc = ata_qc_from_tag(ap, i))) {
5919 			if (finish_qc)
5920 				finish_qc(qc);
5921 			ata_qc_complete(qc);
5922 			nr_done++;
5923 		}
5924 	}
5925 
5926 	return nr_done;
5927 }
5928 
5929 /**
5930  *	ata_qc_issue - issue taskfile to device
5931  *	@qc: command to issue to device
5932  *
5933  *	Prepare an ATA command to submission to device.
5934  *	This includes mapping the data into a DMA-able
5935  *	area, filling in the S/G table, and finally
5936  *	writing the taskfile to hardware, starting the command.
5937  *
5938  *	LOCKING:
5939  *	spin_lock_irqsave(host lock)
5940  */
5941 void ata_qc_issue(struct ata_queued_cmd *qc)
5942 {
5943 	struct ata_port *ap = qc->ap;
5944 	struct ata_link *link = qc->dev->link;
5945 	u8 prot = qc->tf.protocol;
5946 
5947 	/* Make sure only one non-NCQ command is outstanding.  The
5948 	 * check is skipped for old EH because it reuses active qc to
5949 	 * request ATAPI sense.
5950 	 */
5951 	WARN_ON(ap->ops->error_handler && ata_tag_valid(link->active_tag));
5952 
5953 	if (ata_is_ncq(prot)) {
5954 		WARN_ON(link->sactive & (1 << qc->tag));
5955 
5956 		if (!link->sactive)
5957 			ap->nr_active_links++;
5958 		link->sactive |= 1 << qc->tag;
5959 	} else {
5960 		WARN_ON(link->sactive);
5961 
5962 		ap->nr_active_links++;
5963 		link->active_tag = qc->tag;
5964 	}
5965 
5966 	qc->flags |= ATA_QCFLAG_ACTIVE;
5967 	ap->qc_active |= 1 << qc->tag;
5968 
5969 	/* We guarantee to LLDs that they will have at least one
5970 	 * non-zero sg if the command is a data command.
5971 	 */
5972 	BUG_ON(ata_is_data(prot) && (!qc->sg || !qc->n_elem || !qc->nbytes));
5973 
5974 	/* ata_sg_setup() may update nbytes */
5975 	qc->raw_nbytes = qc->nbytes;
5976 
5977 	if (ata_is_dma(prot) || (ata_is_pio(prot) &&
5978 				 (ap->flags & ATA_FLAG_PIO_DMA)))
5979 		if (ata_sg_setup(qc))
5980 			goto sg_err;
5981 
5982 	/* if device is sleeping, schedule softreset and abort the link */
5983 	if (unlikely(qc->dev->flags & ATA_DFLAG_SLEEPING)) {
5984 		link->eh_info.action |= ATA_EH_SOFTRESET;
5985 		ata_ehi_push_desc(&link->eh_info, "waking up from sleep");
5986 		ata_link_abort(link);
5987 		return;
5988 	}
5989 
5990 	ap->ops->qc_prep(qc);
5991 
5992 	qc->err_mask |= ap->ops->qc_issue(qc);
5993 	if (unlikely(qc->err_mask))
5994 		goto err;
5995 	return;
5996 
5997 sg_err:
5998 	qc->err_mask |= AC_ERR_SYSTEM;
5999 err:
6000 	ata_qc_complete(qc);
6001 }
6002 
6003 /**
6004  *	ata_qc_issue_prot - issue taskfile to device in proto-dependent manner
6005  *	@qc: command to issue to device
6006  *
6007  *	Using various libata functions and hooks, this function
6008  *	starts an ATA command.  ATA commands are grouped into
6009  *	classes called "protocols", and issuing each type of protocol
6010  *	is slightly different.
6011  *
6012  *	May be used as the qc_issue() entry in ata_port_operations.
6013  *
6014  *	LOCKING:
6015  *	spin_lock_irqsave(host lock)
6016  *
6017  *	RETURNS:
6018  *	Zero on success, AC_ERR_* mask on failure
6019  */
6020 
6021 unsigned int ata_qc_issue_prot(struct ata_queued_cmd *qc)
6022 {
6023 	struct ata_port *ap = qc->ap;
6024 
6025 	/* Use polling pio if the LLD doesn't handle
6026 	 * interrupt driven pio and atapi CDB interrupt.
6027 	 */
6028 	if (ap->flags & ATA_FLAG_PIO_POLLING) {
6029 		switch (qc->tf.protocol) {
6030 		case ATA_PROT_PIO:
6031 		case ATA_PROT_NODATA:
6032 		case ATAPI_PROT_PIO:
6033 		case ATAPI_PROT_NODATA:
6034 			qc->tf.flags |= ATA_TFLAG_POLLING;
6035 			break;
6036 		case ATAPI_PROT_DMA:
6037 			if (qc->dev->flags & ATA_DFLAG_CDB_INTR)
6038 				/* see ata_dma_blacklisted() */
6039 				BUG();
6040 			break;
6041 		default:
6042 			break;
6043 		}
6044 	}
6045 
6046 	/* select the device */
6047 	ata_dev_select(ap, qc->dev->devno, 1, 0);
6048 
6049 	/* start the command */
6050 	switch (qc->tf.protocol) {
6051 	case ATA_PROT_NODATA:
6052 		if (qc->tf.flags & ATA_TFLAG_POLLING)
6053 			ata_qc_set_polling(qc);
6054 
6055 		ata_tf_to_host(ap, &qc->tf);
6056 		ap->hsm_task_state = HSM_ST_LAST;
6057 
6058 		if (qc->tf.flags & ATA_TFLAG_POLLING)
6059 			ata_pio_queue_task(ap, qc, 0);
6060 
6061 		break;
6062 
6063 	case ATA_PROT_DMA:
6064 		WARN_ON(qc->tf.flags & ATA_TFLAG_POLLING);
6065 
6066 		ap->ops->tf_load(ap, &qc->tf);	 /* load tf registers */
6067 		ap->ops->bmdma_setup(qc);	    /* set up bmdma */
6068 		ap->ops->bmdma_start(qc);	    /* initiate bmdma */
6069 		ap->hsm_task_state = HSM_ST_LAST;
6070 		break;
6071 
6072 	case ATA_PROT_PIO:
6073 		if (qc->tf.flags & ATA_TFLAG_POLLING)
6074 			ata_qc_set_polling(qc);
6075 
6076 		ata_tf_to_host(ap, &qc->tf);
6077 
6078 		if (qc->tf.flags & ATA_TFLAG_WRITE) {
6079 			/* PIO data out protocol */
6080 			ap->hsm_task_state = HSM_ST_FIRST;
6081 			ata_pio_queue_task(ap, qc, 0);
6082 
6083 			/* always send first data block using
6084 			 * the ata_pio_task() codepath.
6085 			 */
6086 		} else {
6087 			/* PIO data in protocol */
6088 			ap->hsm_task_state = HSM_ST;
6089 
6090 			if (qc->tf.flags & ATA_TFLAG_POLLING)
6091 				ata_pio_queue_task(ap, qc, 0);
6092 
6093 			/* if polling, ata_pio_task() handles the rest.
6094 			 * otherwise, interrupt handler takes over from here.
6095 			 */
6096 		}
6097 
6098 		break;
6099 
6100 	case ATAPI_PROT_PIO:
6101 	case ATAPI_PROT_NODATA:
6102 		if (qc->tf.flags & ATA_TFLAG_POLLING)
6103 			ata_qc_set_polling(qc);
6104 
6105 		ata_tf_to_host(ap, &qc->tf);
6106 
6107 		ap->hsm_task_state = HSM_ST_FIRST;
6108 
6109 		/* send cdb by polling if no cdb interrupt */
6110 		if ((!(qc->dev->flags & ATA_DFLAG_CDB_INTR)) ||
6111 		    (qc->tf.flags & ATA_TFLAG_POLLING))
6112 			ata_pio_queue_task(ap, qc, 0);
6113 		break;
6114 
6115 	case ATAPI_PROT_DMA:
6116 		WARN_ON(qc->tf.flags & ATA_TFLAG_POLLING);
6117 
6118 		ap->ops->tf_load(ap, &qc->tf);	 /* load tf registers */
6119 		ap->ops->bmdma_setup(qc);	    /* set up bmdma */
6120 		ap->hsm_task_state = HSM_ST_FIRST;
6121 
6122 		/* send cdb by polling if no cdb interrupt */
6123 		if (!(qc->dev->flags & ATA_DFLAG_CDB_INTR))
6124 			ata_pio_queue_task(ap, qc, 0);
6125 		break;
6126 
6127 	default:
6128 		WARN_ON(1);
6129 		return AC_ERR_SYSTEM;
6130 	}
6131 
6132 	return 0;
6133 }
6134 
6135 /**
6136  *	ata_host_intr - Handle host interrupt for given (port, task)
6137  *	@ap: Port on which interrupt arrived (possibly...)
6138  *	@qc: Taskfile currently active in engine
6139  *
6140  *	Handle host interrupt for given queued command.  Currently,
6141  *	only DMA interrupts are handled.  All other commands are
6142  *	handled via polling with interrupts disabled (nIEN bit).
6143  *
6144  *	LOCKING:
6145  *	spin_lock_irqsave(host lock)
6146  *
6147  *	RETURNS:
6148  *	One if interrupt was handled, zero if not (shared irq).
6149  */
6150 
6151 inline unsigned int ata_host_intr(struct ata_port *ap,
6152 				  struct ata_queued_cmd *qc)
6153 {
6154 	struct ata_eh_info *ehi = &ap->link.eh_info;
6155 	u8 status, host_stat = 0;
6156 
6157 	VPRINTK("ata%u: protocol %d task_state %d\n",
6158 		ap->print_id, qc->tf.protocol, ap->hsm_task_state);
6159 
6160 	/* Check whether we are expecting interrupt in this state */
6161 	switch (ap->hsm_task_state) {
6162 	case HSM_ST_FIRST:
6163 		/* Some pre-ATAPI-4 devices assert INTRQ
6164 		 * at this state when ready to receive CDB.
6165 		 */
6166 
6167 		/* Check the ATA_DFLAG_CDB_INTR flag is enough here.
6168 		 * The flag was turned on only for atapi devices.  No
6169 		 * need to check ata_is_atapi(qc->tf.protocol) again.
6170 		 */
6171 		if (!(qc->dev->flags & ATA_DFLAG_CDB_INTR))
6172 			goto idle_irq;
6173 		break;
6174 	case HSM_ST_LAST:
6175 		if (qc->tf.protocol == ATA_PROT_DMA ||
6176 		    qc->tf.protocol == ATAPI_PROT_DMA) {
6177 			/* check status of DMA engine */
6178 			host_stat = ap->ops->bmdma_status(ap);
6179 			VPRINTK("ata%u: host_stat 0x%X\n",
6180 				ap->print_id, host_stat);
6181 
6182 			/* if it's not our irq... */
6183 			if (!(host_stat & ATA_DMA_INTR))
6184 				goto idle_irq;
6185 
6186 			/* before we do anything else, clear DMA-Start bit */
6187 			ap->ops->bmdma_stop(qc);
6188 
6189 			if (unlikely(host_stat & ATA_DMA_ERR)) {
6190 				/* error when transfering data to/from memory */
6191 				qc->err_mask |= AC_ERR_HOST_BUS;
6192 				ap->hsm_task_state = HSM_ST_ERR;
6193 			}
6194 		}
6195 		break;
6196 	case HSM_ST:
6197 		break;
6198 	default:
6199 		goto idle_irq;
6200 	}
6201 
6202 	/* check altstatus */
6203 	status = ata_altstatus(ap);
6204 	if (status & ATA_BUSY)
6205 		goto idle_irq;
6206 
6207 	/* check main status, clearing INTRQ */
6208 	status = ata_chk_status(ap);
6209 	if (unlikely(status & ATA_BUSY))
6210 		goto idle_irq;
6211 
6212 	/* ack bmdma irq events */
6213 	ap->ops->irq_clear(ap);
6214 
6215 	ata_hsm_move(ap, qc, status, 0);
6216 
6217 	if (unlikely(qc->err_mask) && (qc->tf.protocol == ATA_PROT_DMA ||
6218 				       qc->tf.protocol == ATAPI_PROT_DMA))
6219 		ata_ehi_push_desc(ehi, "BMDMA stat 0x%x", host_stat);
6220 
6221 	return 1;	/* irq handled */
6222 
6223 idle_irq:
6224 	ap->stats.idle_irq++;
6225 
6226 #ifdef ATA_IRQ_TRAP
6227 	if ((ap->stats.idle_irq % 1000) == 0) {
6228 		ata_chk_status(ap);
6229 		ap->ops->irq_clear(ap);
6230 		ata_port_printk(ap, KERN_WARNING, "irq trap\n");
6231 		return 1;
6232 	}
6233 #endif
6234 	return 0;	/* irq not handled */
6235 }
6236 
6237 /**
6238  *	ata_interrupt - Default ATA host interrupt handler
6239  *	@irq: irq line (unused)
6240  *	@dev_instance: pointer to our ata_host information structure
6241  *
6242  *	Default interrupt handler for PCI IDE devices.  Calls
6243  *	ata_host_intr() for each port that is not disabled.
6244  *
6245  *	LOCKING:
6246  *	Obtains host lock during operation.
6247  *
6248  *	RETURNS:
6249  *	IRQ_NONE or IRQ_HANDLED.
6250  */
6251 
6252 irqreturn_t ata_interrupt(int irq, void *dev_instance)
6253 {
6254 	struct ata_host *host = dev_instance;
6255 	unsigned int i;
6256 	unsigned int handled = 0;
6257 	unsigned long flags;
6258 
6259 	/* TODO: make _irqsave conditional on x86 PCI IDE legacy mode */
6260 	spin_lock_irqsave(&host->lock, flags);
6261 
6262 	for (i = 0; i < host->n_ports; i++) {
6263 		struct ata_port *ap;
6264 
6265 		ap = host->ports[i];
6266 		if (ap &&
6267 		    !(ap->flags & ATA_FLAG_DISABLED)) {
6268 			struct ata_queued_cmd *qc;
6269 
6270 			qc = ata_qc_from_tag(ap, ap->link.active_tag);
6271 			if (qc && (!(qc->tf.flags & ATA_TFLAG_POLLING)) &&
6272 			    (qc->flags & ATA_QCFLAG_ACTIVE))
6273 				handled |= ata_host_intr(ap, qc);
6274 		}
6275 	}
6276 
6277 	spin_unlock_irqrestore(&host->lock, flags);
6278 
6279 	return IRQ_RETVAL(handled);
6280 }
6281 
6282 /**
6283  *	sata_scr_valid - test whether SCRs are accessible
6284  *	@link: ATA link to test SCR accessibility for
6285  *
6286  *	Test whether SCRs are accessible for @link.
6287  *
6288  *	LOCKING:
6289  *	None.
6290  *
6291  *	RETURNS:
6292  *	1 if SCRs are accessible, 0 otherwise.
6293  */
6294 int sata_scr_valid(struct ata_link *link)
6295 {
6296 	struct ata_port *ap = link->ap;
6297 
6298 	return (ap->flags & ATA_FLAG_SATA) && ap->ops->scr_read;
6299 }
6300 
6301 /**
6302  *	sata_scr_read - read SCR register of the specified port
6303  *	@link: ATA link to read SCR for
6304  *	@reg: SCR to read
6305  *	@val: Place to store read value
6306  *
6307  *	Read SCR register @reg of @link into *@val.  This function is
6308  *	guaranteed to succeed if @link is ap->link, the cable type of
6309  *	the port is SATA and the port implements ->scr_read.
6310  *
6311  *	LOCKING:
6312  *	None if @link is ap->link.  Kernel thread context otherwise.
6313  *
6314  *	RETURNS:
6315  *	0 on success, negative errno on failure.
6316  */
6317 int sata_scr_read(struct ata_link *link, int reg, u32 *val)
6318 {
6319 	if (ata_is_host_link(link)) {
6320 		struct ata_port *ap = link->ap;
6321 
6322 		if (sata_scr_valid(link))
6323 			return ap->ops->scr_read(ap, reg, val);
6324 		return -EOPNOTSUPP;
6325 	}
6326 
6327 	return sata_pmp_scr_read(link, reg, val);
6328 }
6329 
6330 /**
6331  *	sata_scr_write - write SCR register of the specified port
6332  *	@link: ATA link to write SCR for
6333  *	@reg: SCR to write
6334  *	@val: value to write
6335  *
6336  *	Write @val to SCR register @reg of @link.  This function is
6337  *	guaranteed to succeed if @link is ap->link, the cable type of
6338  *	the port is SATA and the port implements ->scr_read.
6339  *
6340  *	LOCKING:
6341  *	None if @link is ap->link.  Kernel thread context otherwise.
6342  *
6343  *	RETURNS:
6344  *	0 on success, negative errno on failure.
6345  */
6346 int sata_scr_write(struct ata_link *link, int reg, u32 val)
6347 {
6348 	if (ata_is_host_link(link)) {
6349 		struct ata_port *ap = link->ap;
6350 
6351 		if (sata_scr_valid(link))
6352 			return ap->ops->scr_write(ap, reg, val);
6353 		return -EOPNOTSUPP;
6354 	}
6355 
6356 	return sata_pmp_scr_write(link, reg, val);
6357 }
6358 
6359 /**
6360  *	sata_scr_write_flush - write SCR register of the specified port and flush
6361  *	@link: ATA link to write SCR for
6362  *	@reg: SCR to write
6363  *	@val: value to write
6364  *
6365  *	This function is identical to sata_scr_write() except that this
6366  *	function performs flush after writing to the register.
6367  *
6368  *	LOCKING:
6369  *	None if @link is ap->link.  Kernel thread context otherwise.
6370  *
6371  *	RETURNS:
6372  *	0 on success, negative errno on failure.
6373  */
6374 int sata_scr_write_flush(struct ata_link *link, int reg, u32 val)
6375 {
6376 	if (ata_is_host_link(link)) {
6377 		struct ata_port *ap = link->ap;
6378 		int rc;
6379 
6380 		if (sata_scr_valid(link)) {
6381 			rc = ap->ops->scr_write(ap, reg, val);
6382 			if (rc == 0)
6383 				rc = ap->ops->scr_read(ap, reg, &val);
6384 			return rc;
6385 		}
6386 		return -EOPNOTSUPP;
6387 	}
6388 
6389 	return sata_pmp_scr_write(link, reg, val);
6390 }
6391 
6392 /**
6393  *	ata_link_online - test whether the given link is online
6394  *	@link: ATA link to test
6395  *
6396  *	Test whether @link is online.  Note that this function returns
6397  *	0 if online status of @link cannot be obtained, so
6398  *	ata_link_online(link) != !ata_link_offline(link).
6399  *
6400  *	LOCKING:
6401  *	None.
6402  *
6403  *	RETURNS:
6404  *	1 if the port online status is available and online.
6405  */
6406 int ata_link_online(struct ata_link *link)
6407 {
6408 	u32 sstatus;
6409 
6410 	if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0 &&
6411 	    (sstatus & 0xf) == 0x3)
6412 		return 1;
6413 	return 0;
6414 }
6415 
6416 /**
6417  *	ata_link_offline - test whether the given link is offline
6418  *	@link: ATA link to test
6419  *
6420  *	Test whether @link is offline.  Note that this function
6421  *	returns 0 if offline status of @link cannot be obtained, so
6422  *	ata_link_online(link) != !ata_link_offline(link).
6423  *
6424  *	LOCKING:
6425  *	None.
6426  *
6427  *	RETURNS:
6428  *	1 if the port offline status is available and offline.
6429  */
6430 int ata_link_offline(struct ata_link *link)
6431 {
6432 	u32 sstatus;
6433 
6434 	if (sata_scr_read(link, SCR_STATUS, &sstatus) == 0 &&
6435 	    (sstatus & 0xf) != 0x3)
6436 		return 1;
6437 	return 0;
6438 }
6439 
6440 int ata_flush_cache(struct ata_device *dev)
6441 {
6442 	unsigned int err_mask;
6443 	u8 cmd;
6444 
6445 	if (!ata_try_flush_cache(dev))
6446 		return 0;
6447 
6448 	if (dev->flags & ATA_DFLAG_FLUSH_EXT)
6449 		cmd = ATA_CMD_FLUSH_EXT;
6450 	else
6451 		cmd = ATA_CMD_FLUSH;
6452 
6453 	/* This is wrong. On a failed flush we get back the LBA of the lost
6454 	   sector and we should (assuming it wasn't aborted as unknown) issue
6455 	   a further flush command to continue the writeback until it
6456 	   does not error */
6457 	err_mask = ata_do_simple_cmd(dev, cmd);
6458 	if (err_mask) {
6459 		ata_dev_printk(dev, KERN_ERR, "failed to flush cache\n");
6460 		return -EIO;
6461 	}
6462 
6463 	return 0;
6464 }
6465 
6466 #ifdef CONFIG_PM
6467 static int ata_host_request_pm(struct ata_host *host, pm_message_t mesg,
6468 			       unsigned int action, unsigned int ehi_flags,
6469 			       int wait)
6470 {
6471 	unsigned long flags;
6472 	int i, rc;
6473 
6474 	for (i = 0; i < host->n_ports; i++) {
6475 		struct ata_port *ap = host->ports[i];
6476 		struct ata_link *link;
6477 
6478 		/* Previous resume operation might still be in
6479 		 * progress.  Wait for PM_PENDING to clear.
6480 		 */
6481 		if (ap->pflags & ATA_PFLAG_PM_PENDING) {
6482 			ata_port_wait_eh(ap);
6483 			WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
6484 		}
6485 
6486 		/* request PM ops to EH */
6487 		spin_lock_irqsave(ap->lock, flags);
6488 
6489 		ap->pm_mesg = mesg;
6490 		if (wait) {
6491 			rc = 0;
6492 			ap->pm_result = &rc;
6493 		}
6494 
6495 		ap->pflags |= ATA_PFLAG_PM_PENDING;
6496 		__ata_port_for_each_link(link, ap) {
6497 			link->eh_info.action |= action;
6498 			link->eh_info.flags |= ehi_flags;
6499 		}
6500 
6501 		ata_port_schedule_eh(ap);
6502 
6503 		spin_unlock_irqrestore(ap->lock, flags);
6504 
6505 		/* wait and check result */
6506 		if (wait) {
6507 			ata_port_wait_eh(ap);
6508 			WARN_ON(ap->pflags & ATA_PFLAG_PM_PENDING);
6509 			if (rc)
6510 				return rc;
6511 		}
6512 	}
6513 
6514 	return 0;
6515 }
6516 
6517 /**
6518  *	ata_host_suspend - suspend host
6519  *	@host: host to suspend
6520  *	@mesg: PM message
6521  *
6522  *	Suspend @host.  Actual operation is performed by EH.  This
6523  *	function requests EH to perform PM operations and waits for EH
6524  *	to finish.
6525  *
6526  *	LOCKING:
6527  *	Kernel thread context (may sleep).
6528  *
6529  *	RETURNS:
6530  *	0 on success, -errno on failure.
6531  */
6532 int ata_host_suspend(struct ata_host *host, pm_message_t mesg)
6533 {
6534 	int rc;
6535 
6536 	/*
6537 	 * disable link pm on all ports before requesting
6538 	 * any pm activity
6539 	 */
6540 	ata_lpm_enable(host);
6541 
6542 	rc = ata_host_request_pm(host, mesg, 0, ATA_EHI_QUIET, 1);
6543 	if (rc == 0)
6544 		host->dev->power.power_state = mesg;
6545 	return rc;
6546 }
6547 
6548 /**
6549  *	ata_host_resume - resume host
6550  *	@host: host to resume
6551  *
6552  *	Resume @host.  Actual operation is performed by EH.  This
6553  *	function requests EH to perform PM operations and returns.
6554  *	Note that all resume operations are performed parallely.
6555  *
6556  *	LOCKING:
6557  *	Kernel thread context (may sleep).
6558  */
6559 void ata_host_resume(struct ata_host *host)
6560 {
6561 	ata_host_request_pm(host, PMSG_ON, ATA_EH_SOFTRESET,
6562 			    ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET, 0);
6563 	host->dev->power.power_state = PMSG_ON;
6564 
6565 	/* reenable link pm */
6566 	ata_lpm_disable(host);
6567 }
6568 #endif
6569 
6570 /**
6571  *	ata_port_start - Set port up for dma.
6572  *	@ap: Port to initialize
6573  *
6574  *	Called just after data structures for each port are
6575  *	initialized.  Allocates space for PRD table.
6576  *
6577  *	May be used as the port_start() entry in ata_port_operations.
6578  *
6579  *	LOCKING:
6580  *	Inherited from caller.
6581  */
6582 int ata_port_start(struct ata_port *ap)
6583 {
6584 	struct device *dev = ap->dev;
6585 	int rc;
6586 
6587 	ap->prd = dmam_alloc_coherent(dev, ATA_PRD_TBL_SZ, &ap->prd_dma,
6588 				      GFP_KERNEL);
6589 	if (!ap->prd)
6590 		return -ENOMEM;
6591 
6592 	rc = ata_pad_alloc(ap, dev);
6593 	if (rc)
6594 		return rc;
6595 
6596 	DPRINTK("prd alloc, virt %p, dma %llx\n", ap->prd,
6597 		(unsigned long long)ap->prd_dma);
6598 	return 0;
6599 }
6600 
6601 /**
6602  *	ata_dev_init - Initialize an ata_device structure
6603  *	@dev: Device structure to initialize
6604  *
6605  *	Initialize @dev in preparation for probing.
6606  *
6607  *	LOCKING:
6608  *	Inherited from caller.
6609  */
6610 void ata_dev_init(struct ata_device *dev)
6611 {
6612 	struct ata_link *link = dev->link;
6613 	struct ata_port *ap = link->ap;
6614 	unsigned long flags;
6615 
6616 	/* SATA spd limit is bound to the first device */
6617 	link->sata_spd_limit = link->hw_sata_spd_limit;
6618 	link->sata_spd = 0;
6619 
6620 	/* High bits of dev->flags are used to record warm plug
6621 	 * requests which occur asynchronously.  Synchronize using
6622 	 * host lock.
6623 	 */
6624 	spin_lock_irqsave(ap->lock, flags);
6625 	dev->flags &= ~ATA_DFLAG_INIT_MASK;
6626 	dev->horkage = 0;
6627 	spin_unlock_irqrestore(ap->lock, flags);
6628 
6629 	memset((void *)dev + ATA_DEVICE_CLEAR_OFFSET, 0,
6630 	       sizeof(*dev) - ATA_DEVICE_CLEAR_OFFSET);
6631 	dev->pio_mask = UINT_MAX;
6632 	dev->mwdma_mask = UINT_MAX;
6633 	dev->udma_mask = UINT_MAX;
6634 }
6635 
6636 /**
6637  *	ata_link_init - Initialize an ata_link structure
6638  *	@ap: ATA port link is attached to
6639  *	@link: Link structure to initialize
6640  *	@pmp: Port multiplier port number
6641  *
6642  *	Initialize @link.
6643  *
6644  *	LOCKING:
6645  *	Kernel thread context (may sleep)
6646  */
6647 void ata_link_init(struct ata_port *ap, struct ata_link *link, int pmp)
6648 {
6649 	int i;
6650 
6651 	/* clear everything except for devices */
6652 	memset(link, 0, offsetof(struct ata_link, device[0]));
6653 
6654 	link->ap = ap;
6655 	link->pmp = pmp;
6656 	link->active_tag = ATA_TAG_POISON;
6657 	link->hw_sata_spd_limit = UINT_MAX;
6658 
6659 	/* can't use iterator, ap isn't initialized yet */
6660 	for (i = 0; i < ATA_MAX_DEVICES; i++) {
6661 		struct ata_device *dev = &link->device[i];
6662 
6663 		dev->link = link;
6664 		dev->devno = dev - link->device;
6665 		ata_dev_init(dev);
6666 	}
6667 }
6668 
6669 /**
6670  *	sata_link_init_spd - Initialize link->sata_spd_limit
6671  *	@link: Link to configure sata_spd_limit for
6672  *
6673  *	Initialize @link->[hw_]sata_spd_limit to the currently
6674  *	configured value.
6675  *
6676  *	LOCKING:
6677  *	Kernel thread context (may sleep).
6678  *
6679  *	RETURNS:
6680  *	0 on success, -errno on failure.
6681  */
6682 int sata_link_init_spd(struct ata_link *link)
6683 {
6684 	u32 scontrol, spd;
6685 	int rc;
6686 
6687 	rc = sata_scr_read(link, SCR_CONTROL, &scontrol);
6688 	if (rc)
6689 		return rc;
6690 
6691 	spd = (scontrol >> 4) & 0xf;
6692 	if (spd)
6693 		link->hw_sata_spd_limit &= (1 << spd) - 1;
6694 
6695 	link->sata_spd_limit = link->hw_sata_spd_limit;
6696 
6697 	return 0;
6698 }
6699 
6700 /**
6701  *	ata_port_alloc - allocate and initialize basic ATA port resources
6702  *	@host: ATA host this allocated port belongs to
6703  *
6704  *	Allocate and initialize basic ATA port resources.
6705  *
6706  *	RETURNS:
6707  *	Allocate ATA port on success, NULL on failure.
6708  *
6709  *	LOCKING:
6710  *	Inherited from calling layer (may sleep).
6711  */
6712 struct ata_port *ata_port_alloc(struct ata_host *host)
6713 {
6714 	struct ata_port *ap;
6715 
6716 	DPRINTK("ENTER\n");
6717 
6718 	ap = kzalloc(sizeof(*ap), GFP_KERNEL);
6719 	if (!ap)
6720 		return NULL;
6721 
6722 	ap->pflags |= ATA_PFLAG_INITIALIZING;
6723 	ap->lock = &host->lock;
6724 	ap->flags = ATA_FLAG_DISABLED;
6725 	ap->print_id = -1;
6726 	ap->ctl = ATA_DEVCTL_OBS;
6727 	ap->host = host;
6728 	ap->dev = host->dev;
6729 	ap->last_ctl = 0xFF;
6730 
6731 #if defined(ATA_VERBOSE_DEBUG)
6732 	/* turn on all debugging levels */
6733 	ap->msg_enable = 0x00FF;
6734 #elif defined(ATA_DEBUG)
6735 	ap->msg_enable = ATA_MSG_DRV | ATA_MSG_INFO | ATA_MSG_CTL | ATA_MSG_WARN | ATA_MSG_ERR;
6736 #else
6737 	ap->msg_enable = ATA_MSG_DRV | ATA_MSG_ERR | ATA_MSG_WARN;
6738 #endif
6739 
6740 	INIT_DELAYED_WORK(&ap->port_task, ata_pio_task);
6741 	INIT_DELAYED_WORK(&ap->hotplug_task, ata_scsi_hotplug);
6742 	INIT_WORK(&ap->scsi_rescan_task, ata_scsi_dev_rescan);
6743 	INIT_LIST_HEAD(&ap->eh_done_q);
6744 	init_waitqueue_head(&ap->eh_wait_q);
6745 	init_timer_deferrable(&ap->fastdrain_timer);
6746 	ap->fastdrain_timer.function = ata_eh_fastdrain_timerfn;
6747 	ap->fastdrain_timer.data = (unsigned long)ap;
6748 
6749 	ap->cbl = ATA_CBL_NONE;
6750 
6751 	ata_link_init(ap, &ap->link, 0);
6752 
6753 #ifdef ATA_IRQ_TRAP
6754 	ap->stats.unhandled_irq = 1;
6755 	ap->stats.idle_irq = 1;
6756 #endif
6757 	return ap;
6758 }
6759 
6760 static void ata_host_release(struct device *gendev, void *res)
6761 {
6762 	struct ata_host *host = dev_get_drvdata(gendev);
6763 	int i;
6764 
6765 	for (i = 0; i < host->n_ports; i++) {
6766 		struct ata_port *ap = host->ports[i];
6767 
6768 		if (!ap)
6769 			continue;
6770 
6771 		if (ap->scsi_host)
6772 			scsi_host_put(ap->scsi_host);
6773 
6774 		kfree(ap->pmp_link);
6775 		kfree(ap);
6776 		host->ports[i] = NULL;
6777 	}
6778 
6779 	dev_set_drvdata(gendev, NULL);
6780 }
6781 
6782 /**
6783  *	ata_host_alloc - allocate and init basic ATA host resources
6784  *	@dev: generic device this host is associated with
6785  *	@max_ports: maximum number of ATA ports associated with this host
6786  *
6787  *	Allocate and initialize basic ATA host resources.  LLD calls
6788  *	this function to allocate a host, initializes it fully and
6789  *	attaches it using ata_host_register().
6790  *
6791  *	@max_ports ports are allocated and host->n_ports is
6792  *	initialized to @max_ports.  The caller is allowed to decrease
6793  *	host->n_ports before calling ata_host_register().  The unused
6794  *	ports will be automatically freed on registration.
6795  *
6796  *	RETURNS:
6797  *	Allocate ATA host on success, NULL on failure.
6798  *
6799  *	LOCKING:
6800  *	Inherited from calling layer (may sleep).
6801  */
6802 struct ata_host *ata_host_alloc(struct device *dev, int max_ports)
6803 {
6804 	struct ata_host *host;
6805 	size_t sz;
6806 	int i;
6807 
6808 	DPRINTK("ENTER\n");
6809 
6810 	if (!devres_open_group(dev, NULL, GFP_KERNEL))
6811 		return NULL;
6812 
6813 	/* alloc a container for our list of ATA ports (buses) */
6814 	sz = sizeof(struct ata_host) + (max_ports + 1) * sizeof(void *);
6815 	/* alloc a container for our list of ATA ports (buses) */
6816 	host = devres_alloc(ata_host_release, sz, GFP_KERNEL);
6817 	if (!host)
6818 		goto err_out;
6819 
6820 	devres_add(dev, host);
6821 	dev_set_drvdata(dev, host);
6822 
6823 	spin_lock_init(&host->lock);
6824 	host->dev = dev;
6825 	host->n_ports = max_ports;
6826 
6827 	/* allocate ports bound to this host */
6828 	for (i = 0; i < max_ports; i++) {
6829 		struct ata_port *ap;
6830 
6831 		ap = ata_port_alloc(host);
6832 		if (!ap)
6833 			goto err_out;
6834 
6835 		ap->port_no = i;
6836 		host->ports[i] = ap;
6837 	}
6838 
6839 	devres_remove_group(dev, NULL);
6840 	return host;
6841 
6842  err_out:
6843 	devres_release_group(dev, NULL);
6844 	return NULL;
6845 }
6846 
6847 /**
6848  *	ata_host_alloc_pinfo - alloc host and init with port_info array
6849  *	@dev: generic device this host is associated with
6850  *	@ppi: array of ATA port_info to initialize host with
6851  *	@n_ports: number of ATA ports attached to this host
6852  *
6853  *	Allocate ATA host and initialize with info from @ppi.  If NULL
6854  *	terminated, @ppi may contain fewer entries than @n_ports.  The
6855  *	last entry will be used for the remaining ports.
6856  *
6857  *	RETURNS:
6858  *	Allocate ATA host on success, NULL on failure.
6859  *
6860  *	LOCKING:
6861  *	Inherited from calling layer (may sleep).
6862  */
6863 struct ata_host *ata_host_alloc_pinfo(struct device *dev,
6864 				      const struct ata_port_info * const * ppi,
6865 				      int n_ports)
6866 {
6867 	const struct ata_port_info *pi;
6868 	struct ata_host *host;
6869 	int i, j;
6870 
6871 	host = ata_host_alloc(dev, n_ports);
6872 	if (!host)
6873 		return NULL;
6874 
6875 	for (i = 0, j = 0, pi = NULL; i < host->n_ports; i++) {
6876 		struct ata_port *ap = host->ports[i];
6877 
6878 		if (ppi[j])
6879 			pi = ppi[j++];
6880 
6881 		ap->pio_mask = pi->pio_mask;
6882 		ap->mwdma_mask = pi->mwdma_mask;
6883 		ap->udma_mask = pi->udma_mask;
6884 		ap->flags |= pi->flags;
6885 		ap->link.flags |= pi->link_flags;
6886 		ap->ops = pi->port_ops;
6887 
6888 		if (!host->ops && (pi->port_ops != &ata_dummy_port_ops))
6889 			host->ops = pi->port_ops;
6890 		if (!host->private_data && pi->private_data)
6891 			host->private_data = pi->private_data;
6892 	}
6893 
6894 	return host;
6895 }
6896 
6897 static void ata_host_stop(struct device *gendev, void *res)
6898 {
6899 	struct ata_host *host = dev_get_drvdata(gendev);
6900 	int i;
6901 
6902 	WARN_ON(!(host->flags & ATA_HOST_STARTED));
6903 
6904 	for (i = 0; i < host->n_ports; i++) {
6905 		struct ata_port *ap = host->ports[i];
6906 
6907 		if (ap->ops->port_stop)
6908 			ap->ops->port_stop(ap);
6909 	}
6910 
6911 	if (host->ops->host_stop)
6912 		host->ops->host_stop(host);
6913 }
6914 
6915 /**
6916  *	ata_host_start - start and freeze ports of an ATA host
6917  *	@host: ATA host to start ports for
6918  *
6919  *	Start and then freeze ports of @host.  Started status is
6920  *	recorded in host->flags, so this function can be called
6921  *	multiple times.  Ports are guaranteed to get started only
6922  *	once.  If host->ops isn't initialized yet, its set to the
6923  *	first non-dummy port ops.
6924  *
6925  *	LOCKING:
6926  *	Inherited from calling layer (may sleep).
6927  *
6928  *	RETURNS:
6929  *	0 if all ports are started successfully, -errno otherwise.
6930  */
6931 int ata_host_start(struct ata_host *host)
6932 {
6933 	int have_stop = 0;
6934 	void *start_dr = NULL;
6935 	int i, rc;
6936 
6937 	if (host->flags & ATA_HOST_STARTED)
6938 		return 0;
6939 
6940 	for (i = 0; i < host->n_ports; i++) {
6941 		struct ata_port *ap = host->ports[i];
6942 
6943 		if (!host->ops && !ata_port_is_dummy(ap))
6944 			host->ops = ap->ops;
6945 
6946 		if (ap->ops->port_stop)
6947 			have_stop = 1;
6948 	}
6949 
6950 	if (host->ops->host_stop)
6951 		have_stop = 1;
6952 
6953 	if (have_stop) {
6954 		start_dr = devres_alloc(ata_host_stop, 0, GFP_KERNEL);
6955 		if (!start_dr)
6956 			return -ENOMEM;
6957 	}
6958 
6959 	for (i = 0; i < host->n_ports; i++) {
6960 		struct ata_port *ap = host->ports[i];
6961 
6962 		if (ap->ops->port_start) {
6963 			rc = ap->ops->port_start(ap);
6964 			if (rc) {
6965 				if (rc != -ENODEV)
6966 					dev_printk(KERN_ERR, host->dev,
6967 						"failed to start port %d "
6968 						"(errno=%d)\n", i, rc);
6969 				goto err_out;
6970 			}
6971 		}
6972 		ata_eh_freeze_port(ap);
6973 	}
6974 
6975 	if (start_dr)
6976 		devres_add(host->dev, start_dr);
6977 	host->flags |= ATA_HOST_STARTED;
6978 	return 0;
6979 
6980  err_out:
6981 	while (--i >= 0) {
6982 		struct ata_port *ap = host->ports[i];
6983 
6984 		if (ap->ops->port_stop)
6985 			ap->ops->port_stop(ap);
6986 	}
6987 	devres_free(start_dr);
6988 	return rc;
6989 }
6990 
6991 /**
6992  *	ata_sas_host_init - Initialize a host struct
6993  *	@host:	host to initialize
6994  *	@dev:	device host is attached to
6995  *	@flags:	host flags
6996  *	@ops:	port_ops
6997  *
6998  *	LOCKING:
6999  *	PCI/etc. bus probe sem.
7000  *
7001  */
7002 /* KILLME - the only user left is ipr */
7003 void ata_host_init(struct ata_host *host, struct device *dev,
7004 		   unsigned long flags, const struct ata_port_operations *ops)
7005 {
7006 	spin_lock_init(&host->lock);
7007 	host->dev = dev;
7008 	host->flags = flags;
7009 	host->ops = ops;
7010 }
7011 
7012 /**
7013  *	ata_host_register - register initialized ATA host
7014  *	@host: ATA host to register
7015  *	@sht: template for SCSI host
7016  *
7017  *	Register initialized ATA host.  @host is allocated using
7018  *	ata_host_alloc() and fully initialized by LLD.  This function
7019  *	starts ports, registers @host with ATA and SCSI layers and
7020  *	probe registered devices.
7021  *
7022  *	LOCKING:
7023  *	Inherited from calling layer (may sleep).
7024  *
7025  *	RETURNS:
7026  *	0 on success, -errno otherwise.
7027  */
7028 int ata_host_register(struct ata_host *host, struct scsi_host_template *sht)
7029 {
7030 	int i, rc;
7031 
7032 	/* host must have been started */
7033 	if (!(host->flags & ATA_HOST_STARTED)) {
7034 		dev_printk(KERN_ERR, host->dev,
7035 			   "BUG: trying to register unstarted host\n");
7036 		WARN_ON(1);
7037 		return -EINVAL;
7038 	}
7039 
7040 	/* Blow away unused ports.  This happens when LLD can't
7041 	 * determine the exact number of ports to allocate at
7042 	 * allocation time.
7043 	 */
7044 	for (i = host->n_ports; host->ports[i]; i++)
7045 		kfree(host->ports[i]);
7046 
7047 	/* give ports names and add SCSI hosts */
7048 	for (i = 0; i < host->n_ports; i++)
7049 		host->ports[i]->print_id = ata_print_id++;
7050 
7051 	rc = ata_scsi_add_hosts(host, sht);
7052 	if (rc)
7053 		return rc;
7054 
7055 	/* associate with ACPI nodes */
7056 	ata_acpi_associate(host);
7057 
7058 	/* set cable, sata_spd_limit and report */
7059 	for (i = 0; i < host->n_ports; i++) {
7060 		struct ata_port *ap = host->ports[i];
7061 		unsigned long xfer_mask;
7062 
7063 		/* set SATA cable type if still unset */
7064 		if (ap->cbl == ATA_CBL_NONE && (ap->flags & ATA_FLAG_SATA))
7065 			ap->cbl = ATA_CBL_SATA;
7066 
7067 		/* init sata_spd_limit to the current value */
7068 		sata_link_init_spd(&ap->link);
7069 
7070 		/* print per-port info to dmesg */
7071 		xfer_mask = ata_pack_xfermask(ap->pio_mask, ap->mwdma_mask,
7072 					      ap->udma_mask);
7073 
7074 		if (!ata_port_is_dummy(ap)) {
7075 			ata_port_printk(ap, KERN_INFO,
7076 					"%cATA max %s %s\n",
7077 					(ap->flags & ATA_FLAG_SATA) ? 'S' : 'P',
7078 					ata_mode_string(xfer_mask),
7079 					ap->link.eh_info.desc);
7080 			ata_ehi_clear_desc(&ap->link.eh_info);
7081 		} else
7082 			ata_port_printk(ap, KERN_INFO, "DUMMY\n");
7083 	}
7084 
7085 	/* perform each probe synchronously */
7086 	DPRINTK("probe begin\n");
7087 	for (i = 0; i < host->n_ports; i++) {
7088 		struct ata_port *ap = host->ports[i];
7089 		int rc;
7090 
7091 		/* probe */
7092 		if (ap->ops->error_handler) {
7093 			struct ata_eh_info *ehi = &ap->link.eh_info;
7094 			unsigned long flags;
7095 
7096 			ata_port_probe(ap);
7097 
7098 			/* kick EH for boot probing */
7099 			spin_lock_irqsave(ap->lock, flags);
7100 
7101 			ehi->probe_mask =
7102 				(1 << ata_link_max_devices(&ap->link)) - 1;
7103 			ehi->action |= ATA_EH_SOFTRESET;
7104 			ehi->flags |= ATA_EHI_NO_AUTOPSY | ATA_EHI_QUIET;
7105 
7106 			ap->pflags &= ~ATA_PFLAG_INITIALIZING;
7107 			ap->pflags |= ATA_PFLAG_LOADING;
7108 			ata_port_schedule_eh(ap);
7109 
7110 			spin_unlock_irqrestore(ap->lock, flags);
7111 
7112 			/* wait for EH to finish */
7113 			ata_port_wait_eh(ap);
7114 		} else {
7115 			DPRINTK("ata%u: bus probe begin\n", ap->print_id);
7116 			rc = ata_bus_probe(ap);
7117 			DPRINTK("ata%u: bus probe end\n", ap->print_id);
7118 
7119 			if (rc) {
7120 				/* FIXME: do something useful here?
7121 				 * Current libata behavior will
7122 				 * tear down everything when
7123 				 * the module is removed
7124 				 * or the h/w is unplugged.
7125 				 */
7126 			}
7127 		}
7128 	}
7129 
7130 	/* probes are done, now scan each port's disk(s) */
7131 	DPRINTK("host probe begin\n");
7132 	for (i = 0; i < host->n_ports; i++) {
7133 		struct ata_port *ap = host->ports[i];
7134 
7135 		ata_scsi_scan_host(ap, 1);
7136 		ata_lpm_schedule(ap, ap->pm_policy);
7137 	}
7138 
7139 	return 0;
7140 }
7141 
7142 /**
7143  *	ata_host_activate - start host, request IRQ and register it
7144  *	@host: target ATA host
7145  *	@irq: IRQ to request
7146  *	@irq_handler: irq_handler used when requesting IRQ
7147  *	@irq_flags: irq_flags used when requesting IRQ
7148  *	@sht: scsi_host_template to use when registering the host
7149  *
7150  *	After allocating an ATA host and initializing it, most libata
7151  *	LLDs perform three steps to activate the host - start host,
7152  *	request IRQ and register it.  This helper takes necessasry
7153  *	arguments and performs the three steps in one go.
7154  *
7155  *	An invalid IRQ skips the IRQ registration and expects the host to
7156  *	have set polling mode on the port. In this case, @irq_handler
7157  *	should be NULL.
7158  *
7159  *	LOCKING:
7160  *	Inherited from calling layer (may sleep).
7161  *
7162  *	RETURNS:
7163  *	0 on success, -errno otherwise.
7164  */
7165 int ata_host_activate(struct ata_host *host, int irq,
7166 		      irq_handler_t irq_handler, unsigned long irq_flags,
7167 		      struct scsi_host_template *sht)
7168 {
7169 	int i, rc;
7170 
7171 	rc = ata_host_start(host);
7172 	if (rc)
7173 		return rc;
7174 
7175 	/* Special case for polling mode */
7176 	if (!irq) {
7177 		WARN_ON(irq_handler);
7178 		return ata_host_register(host, sht);
7179 	}
7180 
7181 	rc = devm_request_irq(host->dev, irq, irq_handler, irq_flags,
7182 			      dev_driver_string(host->dev), host);
7183 	if (rc)
7184 		return rc;
7185 
7186 	for (i = 0; i < host->n_ports; i++)
7187 		ata_port_desc(host->ports[i], "irq %d", irq);
7188 
7189 	rc = ata_host_register(host, sht);
7190 	/* if failed, just free the IRQ and leave ports alone */
7191 	if (rc)
7192 		devm_free_irq(host->dev, irq, host);
7193 
7194 	return rc;
7195 }
7196 
7197 /**
7198  *	ata_port_detach - Detach ATA port in prepration of device removal
7199  *	@ap: ATA port to be detached
7200  *
7201  *	Detach all ATA devices and the associated SCSI devices of @ap;
7202  *	then, remove the associated SCSI host.  @ap is guaranteed to
7203  *	be quiescent on return from this function.
7204  *
7205  *	LOCKING:
7206  *	Kernel thread context (may sleep).
7207  */
7208 static void ata_port_detach(struct ata_port *ap)
7209 {
7210 	unsigned long flags;
7211 	struct ata_link *link;
7212 	struct ata_device *dev;
7213 
7214 	if (!ap->ops->error_handler)
7215 		goto skip_eh;
7216 
7217 	/* tell EH we're leaving & flush EH */
7218 	spin_lock_irqsave(ap->lock, flags);
7219 	ap->pflags |= ATA_PFLAG_UNLOADING;
7220 	spin_unlock_irqrestore(ap->lock, flags);
7221 
7222 	ata_port_wait_eh(ap);
7223 
7224 	/* EH is now guaranteed to see UNLOADING - EH context belongs
7225 	 * to us.  Disable all existing devices.
7226 	 */
7227 	ata_port_for_each_link(link, ap) {
7228 		ata_link_for_each_dev(dev, link)
7229 			ata_dev_disable(dev);
7230 	}
7231 
7232 	/* Final freeze & EH.  All in-flight commands are aborted.  EH
7233 	 * will be skipped and retrials will be terminated with bad
7234 	 * target.
7235 	 */
7236 	spin_lock_irqsave(ap->lock, flags);
7237 	ata_port_freeze(ap);	/* won't be thawed */
7238 	spin_unlock_irqrestore(ap->lock, flags);
7239 
7240 	ata_port_wait_eh(ap);
7241 	cancel_rearming_delayed_work(&ap->hotplug_task);
7242 
7243  skip_eh:
7244 	/* remove the associated SCSI host */
7245 	scsi_remove_host(ap->scsi_host);
7246 }
7247 
7248 /**
7249  *	ata_host_detach - Detach all ports of an ATA host
7250  *	@host: Host to detach
7251  *
7252  *	Detach all ports of @host.
7253  *
7254  *	LOCKING:
7255  *	Kernel thread context (may sleep).
7256  */
7257 void ata_host_detach(struct ata_host *host)
7258 {
7259 	int i;
7260 
7261 	for (i = 0; i < host->n_ports; i++)
7262 		ata_port_detach(host->ports[i]);
7263 
7264 	/* the host is dead now, dissociate ACPI */
7265 	ata_acpi_dissociate(host);
7266 }
7267 
7268 /**
7269  *	ata_std_ports - initialize ioaddr with standard port offsets.
7270  *	@ioaddr: IO address structure to be initialized
7271  *
7272  *	Utility function which initializes data_addr, error_addr,
7273  *	feature_addr, nsect_addr, lbal_addr, lbam_addr, lbah_addr,
7274  *	device_addr, status_addr, and command_addr to standard offsets
7275  *	relative to cmd_addr.
7276  *
7277  *	Does not set ctl_addr, altstatus_addr, bmdma_addr, or scr_addr.
7278  */
7279 
7280 void ata_std_ports(struct ata_ioports *ioaddr)
7281 {
7282 	ioaddr->data_addr = ioaddr->cmd_addr + ATA_REG_DATA;
7283 	ioaddr->error_addr = ioaddr->cmd_addr + ATA_REG_ERR;
7284 	ioaddr->feature_addr = ioaddr->cmd_addr + ATA_REG_FEATURE;
7285 	ioaddr->nsect_addr = ioaddr->cmd_addr + ATA_REG_NSECT;
7286 	ioaddr->lbal_addr = ioaddr->cmd_addr + ATA_REG_LBAL;
7287 	ioaddr->lbam_addr = ioaddr->cmd_addr + ATA_REG_LBAM;
7288 	ioaddr->lbah_addr = ioaddr->cmd_addr + ATA_REG_LBAH;
7289 	ioaddr->device_addr = ioaddr->cmd_addr + ATA_REG_DEVICE;
7290 	ioaddr->status_addr = ioaddr->cmd_addr + ATA_REG_STATUS;
7291 	ioaddr->command_addr = ioaddr->cmd_addr + ATA_REG_CMD;
7292 }
7293 
7294 
7295 #ifdef CONFIG_PCI
7296 
7297 /**
7298  *	ata_pci_remove_one - PCI layer callback for device removal
7299  *	@pdev: PCI device that was removed
7300  *
7301  *	PCI layer indicates to libata via this hook that hot-unplug or
7302  *	module unload event has occurred.  Detach all ports.  Resource
7303  *	release is handled via devres.
7304  *
7305  *	LOCKING:
7306  *	Inherited from PCI layer (may sleep).
7307  */
7308 void ata_pci_remove_one(struct pci_dev *pdev)
7309 {
7310 	struct device *dev = &pdev->dev;
7311 	struct ata_host *host = dev_get_drvdata(dev);
7312 
7313 	ata_host_detach(host);
7314 }
7315 
7316 /* move to PCI subsystem */
7317 int pci_test_config_bits(struct pci_dev *pdev, const struct pci_bits *bits)
7318 {
7319 	unsigned long tmp = 0;
7320 
7321 	switch (bits->width) {
7322 	case 1: {
7323 		u8 tmp8 = 0;
7324 		pci_read_config_byte(pdev, bits->reg, &tmp8);
7325 		tmp = tmp8;
7326 		break;
7327 	}
7328 	case 2: {
7329 		u16 tmp16 = 0;
7330 		pci_read_config_word(pdev, bits->reg, &tmp16);
7331 		tmp = tmp16;
7332 		break;
7333 	}
7334 	case 4: {
7335 		u32 tmp32 = 0;
7336 		pci_read_config_dword(pdev, bits->reg, &tmp32);
7337 		tmp = tmp32;
7338 		break;
7339 	}
7340 
7341 	default:
7342 		return -EINVAL;
7343 	}
7344 
7345 	tmp &= bits->mask;
7346 
7347 	return (tmp == bits->val) ? 1 : 0;
7348 }
7349 
7350 #ifdef CONFIG_PM
7351 void ata_pci_device_do_suspend(struct pci_dev *pdev, pm_message_t mesg)
7352 {
7353 	pci_save_state(pdev);
7354 	pci_disable_device(pdev);
7355 
7356 	if (mesg.event == PM_EVENT_SUSPEND)
7357 		pci_set_power_state(pdev, PCI_D3hot);
7358 }
7359 
7360 int ata_pci_device_do_resume(struct pci_dev *pdev)
7361 {
7362 	int rc;
7363 
7364 	pci_set_power_state(pdev, PCI_D0);
7365 	pci_restore_state(pdev);
7366 
7367 	rc = pcim_enable_device(pdev);
7368 	if (rc) {
7369 		dev_printk(KERN_ERR, &pdev->dev,
7370 			   "failed to enable device after resume (%d)\n", rc);
7371 		return rc;
7372 	}
7373 
7374 	pci_set_master(pdev);
7375 	return 0;
7376 }
7377 
7378 int ata_pci_device_suspend(struct pci_dev *pdev, pm_message_t mesg)
7379 {
7380 	struct ata_host *host = dev_get_drvdata(&pdev->dev);
7381 	int rc = 0;
7382 
7383 	rc = ata_host_suspend(host, mesg);
7384 	if (rc)
7385 		return rc;
7386 
7387 	ata_pci_device_do_suspend(pdev, mesg);
7388 
7389 	return 0;
7390 }
7391 
7392 int ata_pci_device_resume(struct pci_dev *pdev)
7393 {
7394 	struct ata_host *host = dev_get_drvdata(&pdev->dev);
7395 	int rc;
7396 
7397 	rc = ata_pci_device_do_resume(pdev);
7398 	if (rc == 0)
7399 		ata_host_resume(host);
7400 	return rc;
7401 }
7402 #endif /* CONFIG_PM */
7403 
7404 #endif /* CONFIG_PCI */
7405 
7406 
7407 static int __init ata_init(void)
7408 {
7409 	ata_probe_timeout *= HZ;
7410 	ata_wq = create_workqueue("ata");
7411 	if (!ata_wq)
7412 		return -ENOMEM;
7413 
7414 	ata_aux_wq = create_singlethread_workqueue("ata_aux");
7415 	if (!ata_aux_wq) {
7416 		destroy_workqueue(ata_wq);
7417 		return -ENOMEM;
7418 	}
7419 
7420 	printk(KERN_DEBUG "libata version " DRV_VERSION " loaded.\n");
7421 	return 0;
7422 }
7423 
7424 static void __exit ata_exit(void)
7425 {
7426 	destroy_workqueue(ata_wq);
7427 	destroy_workqueue(ata_aux_wq);
7428 }
7429 
7430 subsys_initcall(ata_init);
7431 module_exit(ata_exit);
7432 
7433 static unsigned long ratelimit_time;
7434 static DEFINE_SPINLOCK(ata_ratelimit_lock);
7435 
7436 int ata_ratelimit(void)
7437 {
7438 	int rc;
7439 	unsigned long flags;
7440 
7441 	spin_lock_irqsave(&ata_ratelimit_lock, flags);
7442 
7443 	if (time_after(jiffies, ratelimit_time)) {
7444 		rc = 1;
7445 		ratelimit_time = jiffies + (HZ/5);
7446 	} else
7447 		rc = 0;
7448 
7449 	spin_unlock_irqrestore(&ata_ratelimit_lock, flags);
7450 
7451 	return rc;
7452 }
7453 
7454 /**
7455  *	ata_wait_register - wait until register value changes
7456  *	@reg: IO-mapped register
7457  *	@mask: Mask to apply to read register value
7458  *	@val: Wait condition
7459  *	@interval_msec: polling interval in milliseconds
7460  *	@timeout_msec: timeout in milliseconds
7461  *
7462  *	Waiting for some bits of register to change is a common
7463  *	operation for ATA controllers.  This function reads 32bit LE
7464  *	IO-mapped register @reg and tests for the following condition.
7465  *
7466  *	(*@reg & mask) != val
7467  *
7468  *	If the condition is met, it returns; otherwise, the process is
7469  *	repeated after @interval_msec until timeout.
7470  *
7471  *	LOCKING:
7472  *	Kernel thread context (may sleep)
7473  *
7474  *	RETURNS:
7475  *	The final register value.
7476  */
7477 u32 ata_wait_register(void __iomem *reg, u32 mask, u32 val,
7478 		      unsigned long interval_msec,
7479 		      unsigned long timeout_msec)
7480 {
7481 	unsigned long timeout;
7482 	u32 tmp;
7483 
7484 	tmp = ioread32(reg);
7485 
7486 	/* Calculate timeout _after_ the first read to make sure
7487 	 * preceding writes reach the controller before starting to
7488 	 * eat away the timeout.
7489 	 */
7490 	timeout = jiffies + (timeout_msec * HZ) / 1000;
7491 
7492 	while ((tmp & mask) == val && time_before(jiffies, timeout)) {
7493 		msleep(interval_msec);
7494 		tmp = ioread32(reg);
7495 	}
7496 
7497 	return tmp;
7498 }
7499 
7500 /*
7501  * Dummy port_ops
7502  */
7503 static void ata_dummy_noret(struct ata_port *ap)	{ }
7504 static int ata_dummy_ret0(struct ata_port *ap)		{ return 0; }
7505 static void ata_dummy_qc_noret(struct ata_queued_cmd *qc) { }
7506 
7507 static u8 ata_dummy_check_status(struct ata_port *ap)
7508 {
7509 	return ATA_DRDY;
7510 }
7511 
7512 static unsigned int ata_dummy_qc_issue(struct ata_queued_cmd *qc)
7513 {
7514 	return AC_ERR_SYSTEM;
7515 }
7516 
7517 const struct ata_port_operations ata_dummy_port_ops = {
7518 	.check_status		= ata_dummy_check_status,
7519 	.check_altstatus	= ata_dummy_check_status,
7520 	.dev_select		= ata_noop_dev_select,
7521 	.qc_prep		= ata_noop_qc_prep,
7522 	.qc_issue		= ata_dummy_qc_issue,
7523 	.freeze			= ata_dummy_noret,
7524 	.thaw			= ata_dummy_noret,
7525 	.error_handler		= ata_dummy_noret,
7526 	.post_internal_cmd	= ata_dummy_qc_noret,
7527 	.irq_clear		= ata_dummy_noret,
7528 	.port_start		= ata_dummy_ret0,
7529 	.port_stop		= ata_dummy_noret,
7530 };
7531 
7532 const struct ata_port_info ata_dummy_port_info = {
7533 	.port_ops		= &ata_dummy_port_ops,
7534 };
7535 
7536 /*
7537  * libata is essentially a library of internal helper functions for
7538  * low-level ATA host controller drivers.  As such, the API/ABI is
7539  * likely to change as new drivers are added and updated.
7540  * Do not depend on ABI/API stability.
7541  */
7542 EXPORT_SYMBOL_GPL(sata_deb_timing_normal);
7543 EXPORT_SYMBOL_GPL(sata_deb_timing_hotplug);
7544 EXPORT_SYMBOL_GPL(sata_deb_timing_long);
7545 EXPORT_SYMBOL_GPL(ata_dummy_port_ops);
7546 EXPORT_SYMBOL_GPL(ata_dummy_port_info);
7547 EXPORT_SYMBOL_GPL(ata_std_bios_param);
7548 EXPORT_SYMBOL_GPL(ata_std_ports);
7549 EXPORT_SYMBOL_GPL(ata_host_init);
7550 EXPORT_SYMBOL_GPL(ata_host_alloc);
7551 EXPORT_SYMBOL_GPL(ata_host_alloc_pinfo);
7552 EXPORT_SYMBOL_GPL(ata_host_start);
7553 EXPORT_SYMBOL_GPL(ata_host_register);
7554 EXPORT_SYMBOL_GPL(ata_host_activate);
7555 EXPORT_SYMBOL_GPL(ata_host_detach);
7556 EXPORT_SYMBOL_GPL(ata_sg_init);
7557 EXPORT_SYMBOL_GPL(ata_hsm_move);
7558 EXPORT_SYMBOL_GPL(ata_qc_complete);
7559 EXPORT_SYMBOL_GPL(ata_qc_complete_multiple);
7560 EXPORT_SYMBOL_GPL(ata_qc_issue_prot);
7561 EXPORT_SYMBOL_GPL(ata_tf_load);
7562 EXPORT_SYMBOL_GPL(ata_tf_read);
7563 EXPORT_SYMBOL_GPL(ata_noop_dev_select);
7564 EXPORT_SYMBOL_GPL(ata_std_dev_select);
7565 EXPORT_SYMBOL_GPL(sata_print_link_status);
7566 EXPORT_SYMBOL_GPL(ata_tf_to_fis);
7567 EXPORT_SYMBOL_GPL(ata_tf_from_fis);
7568 EXPORT_SYMBOL_GPL(ata_pack_xfermask);
7569 EXPORT_SYMBOL_GPL(ata_unpack_xfermask);
7570 EXPORT_SYMBOL_GPL(ata_xfer_mask2mode);
7571 EXPORT_SYMBOL_GPL(ata_xfer_mode2mask);
7572 EXPORT_SYMBOL_GPL(ata_xfer_mode2shift);
7573 EXPORT_SYMBOL_GPL(ata_mode_string);
7574 EXPORT_SYMBOL_GPL(ata_id_xfermask);
7575 EXPORT_SYMBOL_GPL(ata_check_status);
7576 EXPORT_SYMBOL_GPL(ata_altstatus);
7577 EXPORT_SYMBOL_GPL(ata_exec_command);
7578 EXPORT_SYMBOL_GPL(ata_port_start);
7579 EXPORT_SYMBOL_GPL(ata_sff_port_start);
7580 EXPORT_SYMBOL_GPL(ata_interrupt);
7581 EXPORT_SYMBOL_GPL(ata_do_set_mode);
7582 EXPORT_SYMBOL_GPL(ata_data_xfer);
7583 EXPORT_SYMBOL_GPL(ata_data_xfer_noirq);
7584 EXPORT_SYMBOL_GPL(ata_std_qc_defer);
7585 EXPORT_SYMBOL_GPL(ata_qc_prep);
7586 EXPORT_SYMBOL_GPL(ata_dumb_qc_prep);
7587 EXPORT_SYMBOL_GPL(ata_noop_qc_prep);
7588 EXPORT_SYMBOL_GPL(ata_bmdma_setup);
7589 EXPORT_SYMBOL_GPL(ata_bmdma_start);
7590 EXPORT_SYMBOL_GPL(ata_bmdma_irq_clear);
7591 EXPORT_SYMBOL_GPL(ata_bmdma_status);
7592 EXPORT_SYMBOL_GPL(ata_bmdma_stop);
7593 EXPORT_SYMBOL_GPL(ata_bmdma_freeze);
7594 EXPORT_SYMBOL_GPL(ata_bmdma_thaw);
7595 EXPORT_SYMBOL_GPL(ata_bmdma_drive_eh);
7596 EXPORT_SYMBOL_GPL(ata_bmdma_error_handler);
7597 EXPORT_SYMBOL_GPL(ata_bmdma_post_internal_cmd);
7598 EXPORT_SYMBOL_GPL(ata_port_probe);
7599 EXPORT_SYMBOL_GPL(ata_dev_disable);
7600 EXPORT_SYMBOL_GPL(sata_set_spd);
7601 EXPORT_SYMBOL_GPL(sata_link_debounce);
7602 EXPORT_SYMBOL_GPL(sata_link_resume);
7603 EXPORT_SYMBOL_GPL(ata_bus_reset);
7604 EXPORT_SYMBOL_GPL(ata_std_prereset);
7605 EXPORT_SYMBOL_GPL(ata_std_softreset);
7606 EXPORT_SYMBOL_GPL(sata_link_hardreset);
7607 EXPORT_SYMBOL_GPL(sata_std_hardreset);
7608 EXPORT_SYMBOL_GPL(ata_std_postreset);
7609 EXPORT_SYMBOL_GPL(ata_dev_classify);
7610 EXPORT_SYMBOL_GPL(ata_dev_pair);
7611 EXPORT_SYMBOL_GPL(ata_port_disable);
7612 EXPORT_SYMBOL_GPL(ata_ratelimit);
7613 EXPORT_SYMBOL_GPL(ata_wait_register);
7614 EXPORT_SYMBOL_GPL(ata_busy_sleep);
7615 EXPORT_SYMBOL_GPL(ata_wait_after_reset);
7616 EXPORT_SYMBOL_GPL(ata_wait_ready);
7617 EXPORT_SYMBOL_GPL(ata_scsi_ioctl);
7618 EXPORT_SYMBOL_GPL(ata_scsi_queuecmd);
7619 EXPORT_SYMBOL_GPL(ata_scsi_slave_config);
7620 EXPORT_SYMBOL_GPL(ata_scsi_slave_destroy);
7621 EXPORT_SYMBOL_GPL(ata_scsi_change_queue_depth);
7622 EXPORT_SYMBOL_GPL(ata_host_intr);
7623 EXPORT_SYMBOL_GPL(sata_scr_valid);
7624 EXPORT_SYMBOL_GPL(sata_scr_read);
7625 EXPORT_SYMBOL_GPL(sata_scr_write);
7626 EXPORT_SYMBOL_GPL(sata_scr_write_flush);
7627 EXPORT_SYMBOL_GPL(ata_link_online);
7628 EXPORT_SYMBOL_GPL(ata_link_offline);
7629 #ifdef CONFIG_PM
7630 EXPORT_SYMBOL_GPL(ata_host_suspend);
7631 EXPORT_SYMBOL_GPL(ata_host_resume);
7632 #endif /* CONFIG_PM */
7633 EXPORT_SYMBOL_GPL(ata_id_string);
7634 EXPORT_SYMBOL_GPL(ata_id_c_string);
7635 EXPORT_SYMBOL_GPL(ata_scsi_simulate);
7636 
7637 EXPORT_SYMBOL_GPL(ata_pio_need_iordy);
7638 EXPORT_SYMBOL_GPL(ata_timing_find_mode);
7639 EXPORT_SYMBOL_GPL(ata_timing_compute);
7640 EXPORT_SYMBOL_GPL(ata_timing_merge);
7641 EXPORT_SYMBOL_GPL(ata_timing_cycle2mode);
7642 
7643 #ifdef CONFIG_PCI
7644 EXPORT_SYMBOL_GPL(pci_test_config_bits);
7645 EXPORT_SYMBOL_GPL(ata_pci_init_sff_host);
7646 EXPORT_SYMBOL_GPL(ata_pci_init_bmdma);
7647 EXPORT_SYMBOL_GPL(ata_pci_prepare_sff_host);
7648 EXPORT_SYMBOL_GPL(ata_pci_activate_sff_host);
7649 EXPORT_SYMBOL_GPL(ata_pci_init_one);
7650 EXPORT_SYMBOL_GPL(ata_pci_remove_one);
7651 #ifdef CONFIG_PM
7652 EXPORT_SYMBOL_GPL(ata_pci_device_do_suspend);
7653 EXPORT_SYMBOL_GPL(ata_pci_device_do_resume);
7654 EXPORT_SYMBOL_GPL(ata_pci_device_suspend);
7655 EXPORT_SYMBOL_GPL(ata_pci_device_resume);
7656 #endif /* CONFIG_PM */
7657 EXPORT_SYMBOL_GPL(ata_pci_default_filter);
7658 EXPORT_SYMBOL_GPL(ata_pci_clear_simplex);
7659 #endif /* CONFIG_PCI */
7660 
7661 EXPORT_SYMBOL_GPL(sata_pmp_qc_defer_cmd_switch);
7662 EXPORT_SYMBOL_GPL(sata_pmp_std_prereset);
7663 EXPORT_SYMBOL_GPL(sata_pmp_std_hardreset);
7664 EXPORT_SYMBOL_GPL(sata_pmp_std_postreset);
7665 EXPORT_SYMBOL_GPL(sata_pmp_do_eh);
7666 
7667 EXPORT_SYMBOL_GPL(__ata_ehi_push_desc);
7668 EXPORT_SYMBOL_GPL(ata_ehi_push_desc);
7669 EXPORT_SYMBOL_GPL(ata_ehi_clear_desc);
7670 EXPORT_SYMBOL_GPL(ata_port_desc);
7671 #ifdef CONFIG_PCI
7672 EXPORT_SYMBOL_GPL(ata_port_pbar_desc);
7673 #endif /* CONFIG_PCI */
7674 EXPORT_SYMBOL_GPL(ata_port_schedule_eh);
7675 EXPORT_SYMBOL_GPL(ata_link_abort);
7676 EXPORT_SYMBOL_GPL(ata_port_abort);
7677 EXPORT_SYMBOL_GPL(ata_port_freeze);
7678 EXPORT_SYMBOL_GPL(sata_async_notification);
7679 EXPORT_SYMBOL_GPL(ata_eh_freeze_port);
7680 EXPORT_SYMBOL_GPL(ata_eh_thaw_port);
7681 EXPORT_SYMBOL_GPL(ata_eh_qc_complete);
7682 EXPORT_SYMBOL_GPL(ata_eh_qc_retry);
7683 EXPORT_SYMBOL_GPL(ata_do_eh);
7684 EXPORT_SYMBOL_GPL(ata_irq_on);
7685 EXPORT_SYMBOL_GPL(ata_dev_try_classify);
7686 
7687 EXPORT_SYMBOL_GPL(ata_cable_40wire);
7688 EXPORT_SYMBOL_GPL(ata_cable_80wire);
7689 EXPORT_SYMBOL_GPL(ata_cable_unknown);
7690 EXPORT_SYMBOL_GPL(ata_cable_ignore);
7691 EXPORT_SYMBOL_GPL(ata_cable_sata);
7692