summaryrefslogtreecommitdiff
path: root/drivers/ata/libata-sff.c
blob: 8af18ad1ca7f4de2856d6a21b7b495771305120f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
/*
 *  libata-bmdma.c - helper library for PCI IDE BMDMA
 *
 *  Maintained by:  Jeff Garzik <jgarzik@pobox.com>
 *    		    Please ALWAYS copy linux-ide@vger.kernel.org
 *		    on emails.
 *
 *  Copyright 2003-2006 Red Hat, Inc.  All rights reserved.
 *  Copyright 2003-2006 Jeff Garzik
 *
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2, or (at your option)
 *  any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; see the file COPYING.  If not, write to
 *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *
 *  libata documentation is available via 'make {ps|pdf}docs',
 *  as Documentation/DocBook/libata.*
 *
 *  Hardware documentation available from http://www.t13.org/ and
 *  http://www.sata-io.org/
 *
 */

#include <linux/kernel.h>
#include <linux/pci.h>
#include <linux/libata.h>

#include "libata.h"

/**
 *	ata_irq_on - Enable interrupts on a port.
 *	@ap: Port on which interrupts are enabled.
 *
 *	Enable interrupts on a legacy IDE device using MMIO or PIO,
 *	wait for idle, clear any pending interrupts.
 *
 *	LOCKING:
 *	Inherited from caller.
 */
u8 ata_irq_on(struct ata_port *ap)
{
	struct ata_ioports *ioaddr = &ap->ioaddr;
	u8 tmp;

	ap->ctl &= ~ATA_NIEN;
	ap->last_ctl = ap->ctl;

	iowrite8(ap->ctl, ioaddr->ctl_addr);
	tmp = ata_wait_idle(ap);

	ap->ops->irq_clear(ap);

	return tmp;
}

u8 ata_dummy_irq_on (struct ata_port *ap) 	{ return 0; }

/**
 *	ata_irq_ack - Acknowledge a device interrupt.
 *	@ap: Port on which interrupts are enabled.
 *
 *	Wait up to 10 ms for legacy IDE device to become idle (BUSY
 *	or BUSY+DRQ clear).  Obtain dma status and port status from
 *	device.  Clear the interrupt.  Return port status.
 *
 *	LOCKING:
 */

u8 ata_irq_ack(struct ata_port *ap, unsigned int chk_drq)
{
	unsigned int bits = chk_drq ? ATA_BUSY | ATA_DRQ : ATA_BUSY;
	u8 host_stat, post_stat, status;

	status = ata_busy_wait(ap, bits, 1000);
	if (status & bits)
		if (ata_msg_err(ap))
			printk(KERN_ERR "abnormal status 0x%X\n", status);

	/* get controller status; clear intr, err bits */
	host_stat = ioread8(ap->ioaddr.bmdma_addr + ATA_DMA_STATUS);
	iowrite8(host_stat | ATA_DMA_INTR | ATA_DMA_ERR,
		 ap->ioaddr.bmdma_addr + ATA_DMA_STATUS);

	post_stat = ioread8(ap->ioaddr.bmdma_addr + ATA_DMA_STATUS);

	if (ata_msg_intr(ap))
		printk(KERN_INFO "%s: irq ack: host_stat 0x%X, new host_stat 0x%X, drv_stat 0x%X\n",
			__FUNCTION__,
			host_stat, post_stat, status);

	return status;
}

u8 ata_dummy_irq_ack(struct ata_port *ap, unsigned int chk_drq) { return 0; }

/**
 *	ata_tf_load - send taskfile registers to host controller
 *	@ap: Port to which output is sent
 *	@tf: ATA taskfile register set
 *
 *	Outputs ATA taskfile to standard ATA host controller.
 *
 *	LOCKING:
 *	Inherited from caller.
 */

void ata_tf_load(struct ata_port *ap, const struct ata_taskfile *tf)
{
	struct ata_ioports *ioaddr = &ap->ioaddr;
	unsigned int is_addr = tf->flags & ATA_TFLAG_ISADDR;

	if (tf->ctl != ap->last_ctl) {
		iowrite8(tf->ctl, ioaddr->ctl_addr);
		ap->last_ctl = tf->ctl;
		ata_wait_idle(ap);
	}

	if (is_addr && (tf->flags & ATA_TFLAG_LBA48)) {
		iowrite8(tf->hob_feature, ioaddr->feature_addr);
		iowrite8(tf->hob_nsect, ioaddr->nsect_addr);
		iowrite8(tf->hob_lbal, ioaddr->lbal_addr);
		iowrite8(tf->hob_lbam, ioaddr->lbam_addr);
		iowrite8(tf->hob_lbah, ioaddr->lbah_addr);
		VPRINTK("hob: feat 0x%X nsect 0x%X, lba 0x%X 0x%X 0x%X\n",
			tf->hob_feature,
			tf->hob_nsect,
			tf->hob_lbal,
			tf->hob_lbam,
			tf->hob_lbah);
	}

	if (is_addr) {
		iowrite8(tf->feature, ioaddr->feature_addr);
		iowrite8(tf->nsect, ioaddr->nsect_addr);
		iowrite8(tf->lbal, ioaddr->lbal_addr);
		iowrite8(tf->lbam, ioaddr->lbam_addr);
		iowrite8(tf->lbah, ioaddr->lbah_addr);
		VPRINTK("feat 0x%X nsect 0x%X lba 0x%X 0x%X 0x%X\n",
			tf->feature,
			tf->nsect,
			tf->lbal,
			tf->lbam,
			tf->lbah);
	}

	if (tf->flags & ATA_TFLAG_DEVICE) {
		iowrite8(tf->device, ioaddr->device_addr);
		VPRINTK("device 0x%X\n", tf->device);
	}

	ata_wait_idle(ap);
}

/**
 *	ata_exec_command - issue ATA command to host controller
 *	@ap: port to which command is being issued
 *	@tf: ATA taskfile register set
 *
 *	Issues ATA command, with proper synchronization with interrupt
 *	handler / other threads.
 *
 *	LOCKING:
 *	spin_lock_irqsave(host lock)
 */
void ata_exec_command(struct ata_port *ap, const struct ata_taskfile *tf)
{
	DPRINTK("ata%u: cmd 0x%X\n", ap->print_id, tf->command);

	iowrite8(tf->command, ap->ioaddr.command_addr);
	ata_pause(ap);
}

/**
 *	ata_tf_read - input device's ATA taskfile shadow registers
 *	@ap: Port from which input is read
 *	@tf: ATA taskfile register set for storing input
 *
 *	Reads ATA taskfile registers for currently-selected device
 *	into @tf.
 *
 *	LOCKING:
 *	Inherited from caller.
 */
void ata_tf_read(struct ata_port *ap, struct ata_taskfile *tf)
{
	struct ata_ioports *ioaddr = &ap->ioaddr;

	tf->command = ata_check_status(ap);
	tf->feature = ioread8(ioaddr->error_addr);
	tf->nsect = ioread8(ioaddr->nsect_addr);
	tf->lbal = ioread8(ioaddr->lbal_addr);
	tf->lbam = ioread8(ioaddr->lbam_addr);
	tf->lbah = ioread8(ioaddr->lbah_addr);
	tf->device = ioread8(ioaddr->device_addr);

	if (tf->flags & ATA_TFLAG_LBA48) {
		iowrite8(tf->ctl | ATA_HOB, ioaddr->ctl_addr);
		tf->hob_feature = ioread8(ioaddr->error_addr);
		tf->hob_nsect = ioread8(ioaddr->nsect_addr);
		tf->hob_lbal = ioread8(ioaddr->lbal_addr);
		tf->hob_lbam = ioread8(ioaddr->lbam_addr);
		tf->hob_lbah = ioread8(ioaddr->lbah_addr);
	}
}

/**
 *	ata_check_status - Read device status reg & clear interrupt
 *	@ap: port where the device is
 *
 *	Reads ATA taskfile status register for currently-selected device
 *	and return its value. This also clears pending interrupts
 *      from this device
 *
 *	LOCKING:
 *	Inherited from caller.
 */
u8 ata_check_status(struct ata_port *ap)
{
	return ioread8(ap->ioaddr.status_addr);
}

/**
 *	ata_altstatus - Read device alternate status reg
 *	@ap: port where the device is
 *
 *	Reads ATA taskfile alternate status register for
 *	currently-selected device and return its value.
 *
 *	Note: may NOT be used as the check_altstatus() entry in
 *	ata_port_operations.
 *
 *	LOCKING:
 *	Inherited from caller.
 */
u8 ata_altstatus(struct ata_port *ap)
{
	if (ap->ops->check_altstatus)
		return ap->ops->check_altstatus(ap);

	return ioread8(ap->ioaddr.altstatus_addr);
}

/**
 *	ata_bmdma_setup - Set up PCI IDE BMDMA transaction
 *	@qc: Info associated with this ATA transaction.
 *
 *	LOCKING:
 *	spin_lock_irqsave(host lock)
 */
void ata_bmdma_setup(struct ata_queued_cmd *qc)
{
	struct ata_port *ap = qc->ap;
	unsigned int rw = (qc->tf.flags & ATA_TFLAG_WRITE);
	u8 dmactl;

	/* load PRD table addr. */
	mb();	/* make sure PRD table writes are visible to controller */
	iowrite32(ap->prd_dma, ap->ioaddr.bmdma_addr + ATA_DMA_TABLE_OFS);

	/* specify data direction, triple-check start bit is clear */
	dmactl = ioread8(ap->ioaddr.bmdma_addr + ATA_DMA_CMD);
	dmactl &= ~(ATA_DMA_WR | ATA_DMA_START);
	if (!rw)
		dmactl |= ATA_DMA_WR;
	iowrite8(dmactl, ap->ioaddr.bmdma_addr + ATA_DMA_CMD);

	/* issue r/w command */
	ap->ops->exec_command(ap, &qc->tf);
}

/**
 *	ata_bmdma_start - Start a PCI IDE BMDMA transaction
 *	@qc: Info associated with this ATA transaction.
 *
 *	LOCKING:
 *	spin_lock_irqsave(host lock)
 */
void ata_bmdma_start (struct ata_queued_cmd *qc)
{
	struct ata_port *ap = qc->ap;
	u8 dmactl;

	/* start host DMA transaction */
	dmactl = ioread8(ap->ioaddr.bmdma_addr + ATA_DMA_CMD);
	iowrite8(dmactl | ATA_DMA_START, ap->ioaddr.bmdma_addr + ATA_DMA_CMD);

	/* Strictly, one may wish to issue a readb() here, to
	 * flush the mmio write.  However, control also passes
	 * to the hardware at this point, and it will interrupt
	 * us when we are to resume control.  So, in effect,
	 * we don't care when the mmio write flushes.
	 * Further, a read of the DMA status register _immediately_
	 * following the write may not be what certain flaky hardware
	 * is expected, so I think it is best to not add a readb()
	 * without first all the MMIO ATA cards/mobos.
	 * Or maybe I'm just being paranoid.
	 */
}

/**
 *	ata_bmdma_irq_clear - Clear PCI IDE BMDMA interrupt.
 *	@ap: Port associated with this ATA transaction.
 *
 *	Clear interrupt and error flags in DMA status register.
 *
 *	May be used as the irq_clear() entry in ata_port_operations.
 *
 *	LOCKING:
 *	spin_lock_irqsave(host lock)
 */
void ata_bmdma_irq_clear(struct ata_port *ap)
{
	void __iomem *mmio = ap->ioaddr.bmdma_addr;

	if (!mmio)
		return;

	iowrite8(ioread8(mmio + ATA_DMA_STATUS), mmio + ATA_DMA_STATUS);
}

/**
 *	ata_bmdma_status - Read PCI IDE BMDMA status
 *	@ap: Port associated with this ATA transaction.
 *
 *	Read and return BMDMA status register.
 *
 *	May be used as the bmdma_status() entry in ata_port_operations.
 *
 *	LOCKING:
 *	spin_lock_irqsave(host lock)
 */
u8 ata_bmdma_status(struct ata_port *ap)
{
	return ioread8(ap->ioaddr.bmdma_addr + ATA_DMA_STATUS);
}

/**
 *	ata_bmdma_stop - Stop PCI IDE BMDMA transfer
 *	@qc: Command we are ending DMA for
 *
 *	Clears the ATA_DMA_START flag in the dma control register
 *
 *	May be used as the bmdma_stop() entry in ata_port_operations.
 *
 *	LOCKING:
 *	spin_lock_irqsave(host lock)
 */
void ata_bmdma_stop(struct ata_queued_cmd *qc)
{
	struct ata_port *ap = qc->ap;
	void __iomem *mmio = ap->ioaddr.bmdma_addr;

	/* clear start/stop bit */
	iowrite8(ioread8(mmio + ATA_DMA_CMD) & ~ATA_DMA_START,
		 mmio + ATA_DMA_CMD);

	/* one-PIO-cycle guaranteed wait, per spec, for HDMA1:0 transition */
	ata_altstatus(ap);        /* dummy read */
}

/**
 *	ata_bmdma_freeze - Freeze BMDMA controller port
 *	@ap: port to freeze
 *
 *	Freeze BMDMA controller port.
 *
 *	LOCKING:
 *	Inherited from caller.
 */
void ata_bmdma_freeze(struct ata_port *ap)
{
	struct ata_ioports *ioaddr = &ap->ioaddr;

	ap->ctl |= ATA_NIEN;
	ap->last_ctl = ap->ctl;

	iowrite8(ap->ctl, ioaddr->ctl_addr);

	/* Under certain circumstances, some controllers raise IRQ on
	 * ATA_NIEN manipulation.  Also, many controllers fail to mask
	 * previously pending IRQ on ATA_NIEN assertion.  Clear it.
	 */
	ata_chk_status(ap);

	ap->ops->irq_clear(ap);
}

/**
 *	ata_bmdma_thaw - Thaw BMDMA controller port
 *	@ap: port to thaw
 *
 *	Thaw BMDMA controller port.
 *
 *	LOCKING:
 *	Inherited from caller.
 */
void ata_bmdma_thaw(struct ata_port *ap)
{
	/* clear & re-enable interrupts */
	ata_chk_status(ap);
	ap->ops->irq_clear(ap);
	ap->ops->irq_on(ap);
}

/**
 *	ata_bmdma_drive_eh - Perform EH with given methods for BMDMA controller
 *	@ap: port to handle error for
 *	@prereset: prereset method (can be NULL)
 *	@softreset: softreset method (can be NULL)
 *	@hardreset: hardreset method (can be NULL)
 *	@postreset: postreset method (can be NULL)
 *
 *	Handle error for ATA BMDMA controller.  It can handle both
 *	PATA and SATA controllers.  Many controllers should be able to
 *	use this EH as-is or with some added handling before and
 *	after.
 *
 *	This function is intended to be used for constructing
 *	->error_handler callback by low level drivers.
 *
 *	LOCKING:
 *	Kernel thread context (may sleep)
 */
void ata_bmdma_drive_eh(struct ata_port *ap, ata_prereset_fn_t prereset,
			ata_reset_fn_t softreset, ata_reset_fn_t hardreset,
			ata_postreset_fn_t postreset)
{
	struct ata_queued_cmd *qc;
	unsigned long flags;
	int thaw = 0;

	qc = __ata_qc_from_tag(ap, ap->active_tag);
	if (qc && !(qc->flags & ATA_QCFLAG_FAILED))
		qc = NULL;

	/* reset PIO HSM and stop DMA engine */
	spin_lock_irqsave(ap->lock, flags);

	ap->hsm_task_state = HSM_ST_IDLE;

	if (qc && (qc->tf.protocol == ATA_PROT_DMA ||
		   qc->tf.protocol == ATA_PROT_ATAPI_DMA)) {
		u8 host_stat;

		host_stat = ap->ops->bmdma_status(ap);

		/* BMDMA controllers indicate host bus error by
		 * setting DMA_ERR bit and timing out.  As it wasn't
		 * really a timeout event, adjust error mask and
		 * cancel frozen state.
		 */
		if (qc->err_mask == AC_ERR_TIMEOUT && (host_stat & ATA_DMA_ERR)) {
			qc->err_mask = AC_ERR_HOST_BUS;
			thaw = 1;
		}

		ap->ops->bmdma_stop(qc);
	}

	ata_altstatus(ap);
	ata_chk_status(ap);
	ap->ops->irq_clear(ap);

	spin_unlock_irqrestore(ap->lock, flags);

	if (thaw)
		ata_eh_thaw_port(ap);

	/* PIO and DMA engines have been stopped, perform recovery */
	ata_do_eh(ap, prereset, softreset, hardreset, postreset);
}

/**
 *	ata_bmdma_error_handler - Stock error handler for BMDMA controller
 *	@ap: port to handle error for
 *
 *	Stock error handler for BMDMA controller.
 *
 *	LOCKING:
 *	Kernel thread context (may sleep)
 */
void ata_bmdma_error_handler(struct ata_port *ap)
{
	ata_reset_fn_t hardreset;

	hardreset = NULL;
	if (sata_scr_valid(ap))
		hardreset = sata_std_hardreset;

	ata_bmdma_drive_eh(ap, ata_std_prereset, ata_std_softreset, hardreset,
			   ata_std_postreset);
}

/**
 *	ata_bmdma_post_internal_cmd - Stock post_internal_cmd for
 *				      BMDMA controller
 *	@qc: internal command to clean up
 *
 *	LOCKING:
 *	Kernel thread context (may sleep)
 */
void ata_bmdma_post_internal_cmd(struct ata_queued_cmd *qc)
{
	if (qc->ap->ioaddr.bmdma_addr)
		ata_bmdma_stop(qc);
}

#ifdef CONFIG_PCI

static int ata_resources_present(struct pci_dev *pdev, int port)
{
	int i;

	/* Check the PCI resources for this channel are enabled */
	port = port * 2;
	for (i = 0; i < 2; i ++) {
		if (pci_resource_start(pdev, port + i) == 0 ||
		    pci_resource_len(pdev, port + i) == 0)
			return 0;
	}
	return 1;
}

/**
 *	ata_pci_init_bmdma - acquire PCI BMDMA resources and init ATA host
 *	@host: target ATA host
 *
 *	Acquire PCI BMDMA resources and initialize @host accordingly.
 *
 *	LOCKING:
 *	Inherited from calling layer (may sleep).
 *
 *	RETURNS:
 *	0 on success, -errno otherwise.
 */
static int ata_pci_init_bmdma(struct ata_host *host)
{
	struct device *gdev = host->dev;
	struct pci_dev *pdev = to_pci_dev(gdev);
	int i, rc;

	/* TODO: If we get no DMA mask we should fall back to PIO */
	rc = pci_set_dma_mask(pdev, ATA_DMA_MASK);
	if (rc)
		return rc;
	rc = pci_set_consistent_dma_mask(pdev, ATA_DMA_MASK);
	if (rc)
		return rc;

	/* request and iomap DMA region */
	rc = pcim_iomap_regions(pdev, 1 << 4, DRV_NAME);
	if (rc) {
		dev_printk(KERN_ERR, gdev, "failed to request/iomap BAR4\n");
		return -ENOMEM;
	}
	host->iomap = pcim_iomap_table(pdev);

	for (i = 0; i < 2; i++) {
		struct ata_port *ap = host->ports[i];
		void __iomem *bmdma = host->iomap[4] + 8 * i;

		if (ata_port_is_dummy(ap))
			continue;

		ap->ioaddr.bmdma_addr = bmdma;
		if ((!(ap->flags & ATA_FLAG_IGN_SIMPLEX)) &&
		    (ioread8(bmdma + 2) & 0x80))
			host->flags |= ATA_HOST_SIMPLEX;
	}

	return 0;
}

/**
 *	ata_pci_init_native_host - acquire native ATA resources and init host
 *	@host: target ATA host
 *	@port_mask: ports to consider
 *
 *	Acquire native PCI ATA resources for @host and initialize
 *	@host accordoingly.
 *
 *	LOCKING:
 *	Inherited from calling layer (may sleep).
 *
 *	RETURNS:
 *	0 on success, -errno otherwise.
 */
int ata_pci_init_native_host(struct ata_host *host, unsigned int port_mask)
{
	struct device *gdev = host->dev;
	struct pci_dev *pdev = to_pci_dev(gdev);
	int i, rc;

	/* Discard disabled ports.  Some controllers show their unused
	 * channels this way.  Disabled ports are made dummy.
	 */
	for (i = 0; i < 2; i++) {
		if ((port_mask & (1 << i)) && !ata_resources_present(pdev, i)) {
			host->ports[i]->ops = &ata_dummy_port_ops;
			port_mask &= ~(1 << i);
		}
	}

	if (!port_mask) {
		dev_printk(KERN_ERR, gdev, "no available port\n");
		return -ENODEV;
	}

	/* request, iomap BARs and init port addresses accordingly */
	for (i = 0; i < 2; i++) {
		struct ata_port *ap = host->ports[i];
		int base = i * 2;
		void __iomem * const *iomap;

		if (!(port_mask & (1 << i)))
			continue;

		rc = pcim_iomap_regions(pdev, 0x3 << base, DRV_NAME);
		if (rc) {
			dev_printk(KERN_ERR, gdev, "failed to request/iomap "
				   "BARs for port %d (errno=%d)\n", i, rc);
			if (rc == -EBUSY)
				pcim_pin_device(pdev);
			return rc;
		}
		host->iomap = iomap = pcim_iomap_table(pdev);

		ap->ioaddr.cmd_addr = iomap[base];
		ap->ioaddr.altstatus_addr =
		ap->ioaddr.ctl_addr = (void __iomem *)
			((unsigned long)iomap[base + 1] | ATA_PCI_CTL_OFS);
		ata_std_ports(&ap->ioaddr);
	}

	return 0;
}

/**
 *	ata_pci_prepare_native_host - helper to prepare native PCI ATA host
 *	@pdev: target PCI device
 *	@ppi: array of port_info
 *	@n_ports: number of ports to allocate
 *	@r_host: out argument for the initialized ATA host
 *
 *	Helper to allocate ATA host for @pdev, acquire all native PCI
 *	resources and initialize it accordingly in one go.
 *
 *	LOCKING:
 *	Inherited from calling layer (may sleep).
 *
 *	RETURNS:
 *	0 on success, -errno otherwise.
 */
int ata_pci_prepare_native_host(struct pci_dev *pdev,
				const struct ata_port_info * const * ppi,
				int n_ports, struct ata_host **r_host)
{
	struct ata_host *host;
	unsigned int port_mask;
	int rc;

	if (!devres_open_group(&pdev->dev, NULL, GFP_KERNEL))
		return -ENOMEM;

	host = ata_host_alloc_pinfo(&pdev->dev, ppi, 2);
	if (!host) {
		dev_printk(KERN_ERR, &pdev->dev,
			   "failed to allocate ATA host\n");
		rc = -ENOMEM;
		goto err_out;
	}

	port_mask = ATA_PORT_PRIMARY;
	if (n_ports > 1)
		port_mask |= ATA_PORT_SECONDARY;

	rc = ata_pci_init_native_host(host, port_mask);
	if (rc)
		goto err_out;

	/* init DMA related stuff */
	rc = ata_pci_init_bmdma(host);
	if (rc)
		goto err_bmdma;

	devres_remove_group(&pdev->dev, NULL);
	*r_host = host;
	return 0;

 err_bmdma:
	/* This is necessary because PCI and iomap resources are
	 * merged and releasing the top group won't release the
	 * acquired resources if some of those have been acquired
	 * before entering this function.
	 */
	pcim_iounmap_regions(pdev, 0xf);
 err_out:
	devres_release_group(&pdev->dev, NULL);
	return rc;
}

struct ata_legacy_devres {
	unsigned int	mask;
	unsigned long	cmd_port[2];
	void __iomem *	cmd_addr[2];
	void __iomem *	ctl_addr[2];
	unsigned int	irq[2];
	void *		irq_dev_id[2];
};

static void ata_legacy_free_irqs(struct ata_legacy_devres *legacy_dr)
{
	int i;

	for (i = 0; i < 2; i++) {
		if (!legacy_dr->irq[i])
			continue;

		free_irq(legacy_dr->irq[i], legacy_dr->irq_dev_id[i]);
		legacy_dr->irq[i] = 0;
		legacy_dr->irq_dev_id[i] = NULL;
	}
}

static void ata_legacy_release(struct device *gdev, void *res)
{
	struct ata_legacy_devres *this = res;
	int i;

	ata_legacy_free_irqs(this);

	for (i = 0; i < 2; i++) {
		if (this->cmd_addr[i])
			ioport_unmap(this->cmd_addr[i]);
		if (this->ctl_addr[i])
			ioport_unmap(this->ctl_addr[i]);
		if (this->cmd_port[i])
			release_region(this->cmd_port[i], 8);
	}
}

static int ata_init_legacy_port(struct ata_port *ap,
				struct ata_legacy_devres *legacy_dr)
{
	struct ata_host *host = ap->host;
	int port_no = ap->port_no;
	unsigned long cmd_port, ctl_port;

	if (port_no == 0) {
		cmd_port = ATA_PRIMARY_CMD;
		ctl_port = ATA_PRIMARY_CTL;
	} else {
		cmd_port = ATA_SECONDARY_CMD;
		ctl_port = ATA_SECONDARY_CTL;
	}

	/* request cmd_port */
	if (request_region(cmd_port, 8, "libata"))
		legacy_dr->cmd_port[port_no] = cmd_port;
	else {
		dev_printk(KERN_WARNING, host->dev,
			   "0x%0lX IDE port busy\n", cmd_port);
		return -EBUSY;
	}

	/* iomap cmd and ctl ports */
	legacy_dr->cmd_addr[port_no] = ioport_map(cmd_port, 8);
	legacy_dr->ctl_addr[port_no] = ioport_map(ctl_port, 1);
	if (!legacy_dr->cmd_addr[port_no] || !legacy_dr->ctl_addr[port_no])
		return -ENOMEM;

	/* init IO addresses */
	ap->ioaddr.cmd_addr = legacy_dr->cmd_addr[port_no];
	ap->ioaddr.altstatus_addr = legacy_dr->ctl_addr[port_no];
	ap->ioaddr.ctl_addr = legacy_dr->ctl_addr[port_no];
	ata_std_ports(&ap->ioaddr);

	return 0;
}

/**
 *	ata_init_legacy_host - acquire legacy ATA resources and init ATA host
 *	@host: target ATA host
 *	@legacy_mask: out parameter, mask indicating ports is in legacy mode
 *	@was_busy: out parameter, indicates whether any port was busy
 *
 *	Acquire legacy ATA resources for ports.
 *
 *	LOCKING:
 *	Inherited from calling layer (may sleep).
 *
 *	RETURNS:
 *	0 on success, -errno otherwise.
 */
static int ata_init_legacy_host(struct ata_host *host,
				unsigned int *legacy_mask, int *was_busy)
{
	struct device *gdev = host->dev;
	struct ata_legacy_devres *legacy_dr;
	int i, rc;

	if (!devres_open_group(gdev, NULL, GFP_KERNEL))
		return -ENOMEM;

	rc = -ENOMEM;
	legacy_dr = devres_alloc(ata_legacy_release, sizeof(*legacy_dr),
				 GFP_KERNEL);
	if (!legacy_dr)
		goto err_out;
	devres_add(gdev, legacy_dr);

	for (i = 0; i < 2; i++) {
		*legacy_mask &= ~(1 << i);
		rc = ata_init_legacy_port(host->ports[i], legacy_dr);
		if (rc == 0)
			legacy_dr->mask |= 1 << i;
		else if (rc == -EBUSY)
			(*was_busy)++;
	}

	if (!legacy_dr->mask)
		return -EBUSY;

	for (i = 0; i < 2; i++)
		if (!(legacy_dr->mask & (1 << i)))
			host->ports[i]->ops = &ata_dummy_port_ops;

	*legacy_mask |= legacy_dr->mask;

	devres_remove_group(gdev, NULL);
	return 0;

 err_out:
	devres_release_group(gdev, NULL);
	return rc;
}

/**
 *	ata_request_legacy_irqs - request legacy ATA IRQs
 *	@host: target ATA host
 *	@handler: array of IRQ handlers
 *	@irq_flags: array of IRQ flags
 *	@dev_id: array of IRQ dev_ids
 *
 *	Request legacy IRQs for non-dummy legacy ports in @host.  All
 *	IRQ parameters are passed as array to allow ports to have
 *	separate IRQ handlers.
 *
 *	LOCKING:
 *	Inherited from calling layer (may sleep).
 *
 *	RETURNS:
 *	0 on success, -errno otherwise.
 */
static int ata_request_legacy_irqs(struct ata_host *host,
				   irq_handler_t const *handler,
				   const unsigned int *irq_flags,
				   void * const *dev_id)
{
	struct device *gdev = host->dev;
	struct ata_legacy_devres *legacy_dr;
	int i, rc;

	legacy_dr = devres_find(host->dev, ata_legacy_release, NULL, NULL);
	BUG_ON(!legacy_dr);

	for (i = 0; i < 2; i++) {
		unsigned int irq;

		/* FIXME: ATA_*_IRQ() should take generic device not pci_dev */
		if (i == 0)
			irq = ATA_PRIMARY_IRQ(to_pci_dev(gdev));
		else
			irq = ATA_SECONDARY_IRQ(to_pci_dev(gdev));

		if (!(legacy_dr->mask & (1 << i)))
			continue;

		if (!handler[i]) {
			dev_printk(KERN_ERR, gdev,
				   "NULL handler specified for port %d\n", i);
			rc = -EINVAL;
			goto err_out;
		}

		rc = request_irq(irq, handler[i], irq_flags[i], DRV_NAME,
				 dev_id[i]);
		if (rc) {
			dev_printk(KERN_ERR, gdev,
				"irq %u request failed (errno=%d)\n", irq, rc);
			goto err_out;
		}

		/* record irq allocation in legacy_dr */
		legacy_dr->irq[i] = irq;
		legacy_dr->irq_dev_id[i] = dev_id[i];

		/* only used to print info */
		if (i == 0)
			host->irq = irq;
		else
			host->irq2 = irq;
	}

	return 0;

 err_out:
	ata_legacy_free_irqs(legacy_dr);
	return rc;
}

/**
 *	ata_pci_init_one - Initialize/register PCI IDE host controller
 *	@pdev: Controller to be initialized
 *	@port_info: Information from low-level host driver
 *	@n_ports: Number of ports attached to host controller
 *
 *	This is a helper function which can be called from a driver's
 *	xxx_init_one() probe function if the hardware uses traditional
 *	IDE taskfile registers.
 *
 *	This function calls pci_enable_device(), reserves its register
 *	regions, sets the dma mask, enables bus master mode, and calls
 *	ata_device_add()
 *
 *	ASSUMPTION:
 *	Nobody makes a single channel controller that appears solely as
 *	the secondary legacy port on PCI.
 *
 *	LOCKING:
 *	Inherited from PCI layer (may sleep).
 *
 *	RETURNS:
 *	Zero on success, negative on errno-based value on error.
 */

int ata_pci_init_one (struct pci_dev *pdev, struct ata_port_info **port_info,
		      unsigned int n_ports)
{
	struct device *dev = &pdev->dev;
	struct ata_host *host = NULL;
	const struct ata_port_info *port[2];
	u8 mask;
	unsigned int legacy_mode = 0;
	int rc;

	DPRINTK("ENTER\n");

	if (!devres_open_group(dev, NULL, GFP_KERNEL))
		return -ENOMEM;

	BUG_ON(n_ports < 1 || n_ports > 2);

	port[0] = port_info[0];
	if (n_ports > 1)
		port[1] = port_info[1];
	else
		port[1] = port[0];

	/* FIXME: Really for ATA it isn't safe because the device may be
	   multi-purpose and we want to leave it alone if it was already
	   enabled. Secondly for shared use as Arjan says we want refcounting

	   Checking dev->is_enabled is insufficient as this is not set at
	   boot for the primary video which is BIOS enabled
	  */

	rc = pcim_enable_device(pdev);
	if (rc)
		goto err_out;

	if ((pdev->class >> 8) == PCI_CLASS_STORAGE_IDE) {
		u8 tmp8;

		/* TODO: What if one channel is in native mode ... */
		pci_read_config_byte(pdev, PCI_CLASS_PROG, &tmp8);
		mask = (1 << 2) | (1 << 0);
		if ((tmp8 & mask) != mask)
			legacy_mode = (1 << 3);
#if defined(CONFIG_NO_ATA_LEGACY)
		/* Some platforms with PCI limits cannot address compat
		   port space. In that case we punt if their firmware has
		   left a device in compatibility mode */
		if (legacy_mode) {
			printk(KERN_ERR "ata: Compatibility mode ATA is not supported on this platform, skipping.\n");
			rc = -EOPNOTSUPP;
			goto err_out;
		}
#endif
	}

	/* alloc and init host */
	host = ata_host_alloc_pinfo(dev, port, 2);
	if (!host) {
		dev_printk(KERN_ERR, &pdev->dev,
			   "failed to allocate ATA host\n");
		rc = -ENOMEM;
		goto err_out;
	}

	if (!legacy_mode) {
		unsigned int port_mask;

		port_mask = ATA_PORT_PRIMARY;
		if (n_ports > 1)
			port_mask |= ATA_PORT_SECONDARY;

		rc = ata_pci_init_native_host(host, port_mask);
		if (rc)
			goto err_out;
	} else {
		int was_busy = 0;

		rc = ata_init_legacy_host(host, &legacy_mode, &was_busy);
		if (was_busy)
			pcim_pin_device(pdev);
		if (rc)
			goto err_out;

		/* request respective PCI regions, may fail */
		rc = pci_request_region(pdev, 1, DRV_NAME);
		rc = pci_request_region(pdev, 3, DRV_NAME);
	}

	/* init BMDMA, may fail */
	ata_pci_init_bmdma(host);
	pci_set_master(pdev);

	/* start host and request IRQ */
	rc = ata_host_start(host);
	if (rc)
		goto err_out;

	if (!legacy_mode)
		rc = devm_request_irq(dev, pdev->irq,
				      port_info[0]->port_ops->irq_handler,
				      IRQF_SHARED, DRV_NAME, host);
	else {
		irq_handler_t handler[2] = { host->ops->irq_handler,
					     host->ops->irq_handler };
		unsigned int irq_flags[2] = { IRQF_SHARED, IRQF_SHARED };
		void *dev_id[2] = { host, host };

		rc = ata_request_legacy_irqs(host, handler, irq_flags, dev_id);
	}
	if (rc)
		goto err_out;

	/* register */
	rc = ata_host_register(host, port_info[0]->sht);
	if (rc)
		goto err_out;

	devres_remove_group(dev, NULL);
	return 0;

err_out:
	devres_release_group(dev, NULL);
	return rc;
}

/**
 *	ata_pci_clear_simplex	-	attempt to kick device out of simplex
 *	@pdev: PCI device
 *
 *	Some PCI ATA devices report simplex mode but in fact can be told to
 *	enter non simplex mode. This implements the neccessary logic to
 *	perform the task on such devices. Calling it on other devices will
 *	have -undefined- behaviour.
 */

int ata_pci_clear_simplex(struct pci_dev *pdev)
{
	unsigned long bmdma = pci_resource_start(pdev, 4);
	u8 simplex;

	if (bmdma == 0)
		return -ENOENT;

	simplex = inb(bmdma + 0x02);
	outb(simplex & 0x60, bmdma + 0x02);
	simplex = inb(bmdma + 0x02);
	if (simplex & 0x80)
		return -EOPNOTSUPP;
	return 0;
}

unsigned long ata_pci_default_filter(struct ata_device *adev, unsigned long xfer_mask)
{
	/* Filter out DMA modes if the device has been configured by
	   the BIOS as PIO only */

	if (adev->ap->ioaddr.bmdma_addr == 0)
		xfer_mask &= ~(ATA_MASK_MWDMA | ATA_MASK_UDMA);
	return xfer_mask;
}

#endif /* CONFIG_PCI */