aboutsummaryrefslogtreecommitdiff
path: root/drivers/block/umem.c
blob: e93e99c9103cab771f514c2cc02e677deed910c8 (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
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
/*
 * mm.c - Micro Memory(tm) PCI memory board block device driver - v2.3
 *
 * (C) 2001 San Mehat <nettwerk@valinux.com>
 * (C) 2001 Johannes Erdfelt <jerdfelt@valinux.com>
 * (C) 2001 NeilBrown <neilb@cse.unsw.edu.au>
 *
 * This driver for the Micro Memory PCI Memory Module with Battery Backup
 * is Copyright Micro Memory Inc 2001-2002.  All rights reserved.
 *
 * This driver is released to the public under the terms of the
 *  GNU GENERAL PUBLIC LICENSE version 2
 * See the file COPYING for details.
 *
 * This driver provides a standard block device interface for Micro Memory(tm)
 * PCI based RAM boards.
 * 10/05/01: Phap Nguyen - Rebuilt the driver
 * 10/22/01: Phap Nguyen - v2.1 Added disk partitioning
 * 29oct2001:NeilBrown   - Use make_request_fn instead of request_fn
 *                       - use stand disk partitioning (so fdisk works).
 * 08nov2001:NeilBrown	 - change driver name from "mm" to "umem"
 *			 - incorporate into main kernel
 * 08apr2002:NeilBrown   - Move some of interrupt handle to tasklet
 *			 - use spin_lock_bh instead of _irq
 *			 - Never block on make_request.  queue
 *			   bh's instead.
 *			 - unregister umem from devfs at mod unload
 *			 - Change version to 2.3
 * 07Nov2001:Phap Nguyen - Select pci read command: 06, 12, 15 (Decimal)
 * 07Jan2002: P. Nguyen  - Used PCI Memory Write & Invalidate for DMA
 * 15May2002:NeilBrown   - convert to bio for 2.5
 * 17May2002:NeilBrown   - remove init_mem initialisation.  Instead detect
 *			 - a sequence of writes that cover the card, and
 *			 - set initialised bit then.
 */

#undef DEBUG	/* #define DEBUG if you want debugging info (pr_debug) */
#include <linux/fs.h>
#include <linux/bio.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <linux/mman.h>
#include <linux/ioctl.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/timer.h>
#include <linux/pci.h>
#include <linux/slab.h>
#include <linux/dma-mapping.h>

#include <linux/fcntl.h>        /* O_ACCMODE */
#include <linux/hdreg.h>  /* HDIO_GETGEO */

#include "umem.h"

#include <asm/uaccess.h>
#include <asm/io.h>

#define MM_MAXCARDS 4
#define MM_RAHEAD 2      /* two sectors */
#define MM_BLKSIZE 1024  /* 1k blocks */
#define MM_HARDSECT 512  /* 512-byte hardware sectors */
#define MM_SHIFT 6       /* max 64 partitions on 4 cards  */

/*
 * Version Information
 */

#define DRIVER_NAME	"umem"
#define DRIVER_VERSION	"v2.3"
#define DRIVER_AUTHOR	"San Mehat, Johannes Erdfelt, NeilBrown"
#define DRIVER_DESC	"Micro Memory(tm) PCI memory board block driver"

static int debug;
/* #define HW_TRACE(x)     writeb(x,cards[0].csr_remap + MEMCTRLSTATUS_MAGIC) */
#define HW_TRACE(x)

#define DEBUG_LED_ON_TRANSFER	0x01
#define DEBUG_BATTERY_POLLING	0x02

module_param(debug, int, 0644);
MODULE_PARM_DESC(debug, "Debug bitmask");

static int pci_read_cmd = 0x0C;		/* Read Multiple */
module_param(pci_read_cmd, int, 0);
MODULE_PARM_DESC(pci_read_cmd, "PCI read command");

static int pci_write_cmd = 0x0F;	/* Write and Invalidate */
module_param(pci_write_cmd, int, 0);
MODULE_PARM_DESC(pci_write_cmd, "PCI write command");

static int pci_cmds;

static int major_nr;

#include <linux/blkdev.h>
#include <linux/blkpg.h>

struct cardinfo {
	struct pci_dev	*dev;

	unsigned char	__iomem *csr_remap;
	unsigned int	mm_size;  /* size in kbytes */

	unsigned int	init_size; /* initial segment, in sectors,
				    * that we know to
				    * have been written
				    */
	struct bio	*bio, *currentbio, **biotail;
	int		current_idx;
	sector_t	current_sector;

	struct request_queue *queue;

	struct mm_page {
		dma_addr_t		page_dma;
		struct mm_dma_desc	*desc;
		int	 		cnt, headcnt;
		struct bio		*bio, **biotail;
		int			idx;
	} mm_pages[2];
#define DESC_PER_PAGE ((PAGE_SIZE*2)/sizeof(struct mm_dma_desc))

	int  Active, Ready;

	struct tasklet_struct	tasklet;
	unsigned int dma_status;

	struct {
		int		good;
		int		warned;
		unsigned long	last_change;
	} battery[2];

	spinlock_t 	lock;
	int		check_batteries;

	int		flags;
};

static struct cardinfo cards[MM_MAXCARDS];
static struct block_device_operations mm_fops;
static struct timer_list battery_timer;

static int num_cards;

static struct gendisk *mm_gendisk[MM_MAXCARDS];

static void check_batteries(struct cardinfo *card);

static int get_userbit(struct cardinfo *card, int bit)
{
	unsigned char led;

	led = readb(card->csr_remap + MEMCTRLCMD_LEDCTRL);
	return led & bit;
}

static int set_userbit(struct cardinfo *card, int bit, unsigned char state)
{
	unsigned char led;

	led = readb(card->csr_remap + MEMCTRLCMD_LEDCTRL);
	if (state)
		led |= bit;
	else
		led &= ~bit;
	writeb(led, card->csr_remap + MEMCTRLCMD_LEDCTRL);

	return 0;
}

/*
 * NOTE: For the power LED, use the LED_POWER_* macros since they differ
 */
static void set_led(struct cardinfo *card, int shift, unsigned char state)
{
	unsigned char led;

	led = readb(card->csr_remap + MEMCTRLCMD_LEDCTRL);
	if (state == LED_FLIP)
		led ^= (1<<shift);
	else {
		led &= ~(0x03 << shift);
		led |= (state << shift);
	}
	writeb(led, card->csr_remap + MEMCTRLCMD_LEDCTRL);

}

#ifdef MM_DIAG
static void dump_regs(struct cardinfo *card)
{
	unsigned char *p;
	int i, i1;

	p = card->csr_remap;
	for (i = 0; i < 8; i++) {
		printk(KERN_DEBUG "%p   ", p);

		for (i1 = 0; i1 < 16; i1++)
			printk("%02x ", *p++);

		printk("\n");
	}
}
#endif

static void dump_dmastat(struct cardinfo *card, unsigned int dmastat)
{
	dev_printk(KERN_DEBUG, &card->dev->dev, "DMAstat - ");
	if (dmastat & DMASCR_ANY_ERR)
		printk(KERN_CONT "ANY_ERR ");
	if (dmastat & DMASCR_MBE_ERR)
		printk(KERN_CONT "MBE_ERR ");
	if (dmastat & DMASCR_PARITY_ERR_REP)
		printk(KERN_CONT "PARITY_ERR_REP ");
	if (dmastat & DMASCR_PARITY_ERR_DET)
		printk(KERN_CONT "PARITY_ERR_DET ");
	if (dmastat & DMASCR_SYSTEM_ERR_SIG)
		printk(KERN_CONT "SYSTEM_ERR_SIG ");
	if (dmastat & DMASCR_TARGET_ABT)
		printk(KERN_CONT "TARGET_ABT ");
	if (dmastat & DMASCR_MASTER_ABT)
		printk(KERN_CONT "MASTER_ABT ");
	if (dmastat & DMASCR_CHAIN_COMPLETE)
		printk(KERN_CONT "CHAIN_COMPLETE ");
	if (dmastat & DMASCR_DMA_COMPLETE)
		printk(KERN_CONT "DMA_COMPLETE ");
	printk("\n");
}

/*
 * Theory of request handling
 *
 * Each bio is assigned to one mm_dma_desc - which may not be enough FIXME
 * We have two pages of mm_dma_desc, holding about 64 descriptors
 * each.  These are allocated at init time.
 * One page is "Ready" and is either full, or can have request added.
 * The other page might be "Active", which DMA is happening on it.
 *
 * Whenever IO on the active page completes, the Ready page is activated
 * and the ex-Active page is clean out and made Ready.
 * Otherwise the Ready page is only activated when it becomes full, or
 * when mm_unplug_device is called via the unplug_io_fn.
 *
 * If a request arrives while both pages a full, it is queued, and b_rdev is
 * overloaded to record whether it was a read or a write.
 *
 * The interrupt handler only polls the device to clear the interrupt.
 * The processing of the result is done in a tasklet.
 */

static void mm_start_io(struct cardinfo *card)
{
	/* we have the lock, we know there is
	 * no IO active, and we know that card->Active
	 * is set
	 */
	struct mm_dma_desc *desc;
	struct mm_page *page;
	int offset;

	/* make the last descriptor end the chain */
	page = &card->mm_pages[card->Active];
	pr_debug("start_io: %d %d->%d\n",
		card->Active, page->headcnt, page->cnt - 1);
	desc = &page->desc[page->cnt-1];

	desc->control_bits |= cpu_to_le32(DMASCR_CHAIN_COMP_EN);
	desc->control_bits &= ~cpu_to_le32(DMASCR_CHAIN_EN);
	desc->sem_control_bits = desc->control_bits;


	if (debug & DEBUG_LED_ON_TRANSFER)
		set_led(card, LED_REMOVE, LED_ON);

	desc = &page->desc[page->headcnt];
	writel(0, card->csr_remap + DMA_PCI_ADDR);
	writel(0, card->csr_remap + DMA_PCI_ADDR + 4);

	writel(0, card->csr_remap + DMA_LOCAL_ADDR);
	writel(0, card->csr_remap + DMA_LOCAL_ADDR + 4);

	writel(0, card->csr_remap + DMA_TRANSFER_SIZE);
	writel(0, card->csr_remap + DMA_TRANSFER_SIZE + 4);

	writel(0, card->csr_remap + DMA_SEMAPHORE_ADDR);
	writel(0, card->csr_remap + DMA_SEMAPHORE_ADDR + 4);

	offset = ((char *)desc) - ((char *)page->desc);
	writel(cpu_to_le32((page->page_dma+offset) & 0xffffffff),
	       card->csr_remap + DMA_DESCRIPTOR_ADDR);
	/* Force the value to u64 before shifting otherwise >> 32 is undefined C
	 * and on some ports will do nothing ! */
	writel(cpu_to_le32(((u64)page->page_dma)>>32),
	       card->csr_remap + DMA_DESCRIPTOR_ADDR + 4);

	/* Go, go, go */
	writel(cpu_to_le32(DMASCR_GO | DMASCR_CHAIN_EN | pci_cmds),
	       card->csr_remap + DMA_STATUS_CTRL);
}

static int add_bio(struct cardinfo *card);

static void activate(struct cardinfo *card)
{
	/* if No page is Active, and Ready is
	 * not empty, then switch Ready page
	 * to active and start IO.
	 * Then add any bh's that are available to Ready
	 */

	do {
		while (add_bio(card))
			;

		if (card->Active == -1 &&
		    card->mm_pages[card->Ready].cnt > 0) {
			card->Active = card->Ready;
			card->Ready = 1-card->Ready;
			mm_start_io(card);
		}

	} while (card->Active == -1 && add_bio(card));
}

static inline void reset_page(struct mm_page *page)
{
	page->cnt = 0;
	page->headcnt = 0;
	page->bio = NULL;
	page->biotail = &page->bio;
}

static void mm_unplug_device(struct request_queue *q)
{
	struct cardinfo *card = q->queuedata;
	unsigned long flags;

	spin_lock_irqsave(&card->lock, flags);
	if (blk_remove_plug(q))
		activate(card);
	spin_unlock_irqrestore(&card->lock, flags);
}

/*
 * If there is room on Ready page, take
 * one bh off list and add it.
 * return 1 if there was room, else 0.
 */
static int add_bio(struct cardinfo *card)
{
	struct mm_page *p;
	struct mm_dma_desc *desc;
	dma_addr_t dma_handle;
	int offset;
	struct bio *bio;
	struct bio_vec *vec;
	int idx;
	int rw;
	int len;

	bio = card->currentbio;
	if (!bio && card->bio) {
		card->currentbio = card->bio;
		card->current_idx = card->bio->bi_idx;
		card->current_sector = card->bio->bi_sector;
		card->bio = card->bio->bi_next;
		if (card->bio == NULL)
			card->biotail = &card->bio;
		card->currentbio->bi_next = NULL;
		return 1;
	}
	if (!bio)
		return 0;
	idx = card->current_idx;

	rw = bio_rw(bio);
	if (card->mm_pages[card->Ready].cnt >= DESC_PER_PAGE)
		return 0;

	vec = bio_iovec_idx(bio, idx);
	len = vec->bv_len;
	dma_handle = pci_map_page(card->dev,
				  vec->bv_page,
				  vec->bv_offset,
				  len,
				  (rw == READ) ?
				  PCI_DMA_FROMDEVICE : PCI_DMA_TODEVICE);

	p = &card->mm_pages[card->Ready];
	desc = &p->desc[p->cnt];
	p->cnt++;
	if (p->bio == NULL)
		p->idx = idx;
	if ((p->biotail) != &bio->bi_next) {
		*(p->biotail) = bio;
		p->biotail = &(bio->bi_next);
		bio->bi_next = NULL;
	}

	desc->data_dma_handle = dma_handle;

	desc->pci_addr = cpu_to_le64((u64)desc->data_dma_handle);
	desc->local_addr = cpu_to_le64(card->current_sector << 9);
	desc->transfer_size = cpu_to_le32(len);
	offset = (((char *)&desc->sem_control_bits) - ((char *)p->desc));
	desc->sem_addr = cpu_to_le64((u64)(p->page_dma+offset));
	desc->zero1 = desc->zero2 = 0;
	offset = (((char *)(desc+1)) - ((char *)p->desc));
	desc->next_desc_addr = cpu_to_le64(p->page_dma+offset);
	desc->control_bits = cpu_to_le32(DMASCR_GO|DMASCR_ERR_INT_EN|
					 DMASCR_PARITY_INT_EN|
					 DMASCR_CHAIN_EN |
					 DMASCR_SEM_EN |
					 pci_cmds);
	if (rw == WRITE)
		desc->control_bits |= cpu_to_le32(DMASCR_TRANSFER_READ);
	desc->sem_control_bits = desc->control_bits;

	card->current_sector += (len >> 9);
	idx++;
	card->current_idx = idx;
	if (idx >= bio->bi_vcnt)
		card->currentbio = NULL;

	return 1;
}

static void process_page(unsigned long data)
{
	/* check if any of the requests in the page are DMA_COMPLETE,
	 * and deal with them appropriately.
	 * If we find a descriptor without DMA_COMPLETE in the semaphore, then
	 * dma must have hit an error on that descriptor, so use dma_status
	 * instead and assume that all following descriptors must be re-tried.
	 */
	struct mm_page *page;
	struct bio *return_bio = NULL;
	struct cardinfo *card = (struct cardinfo *)data;
	unsigned int dma_status = card->dma_status;

	spin_lock_bh(&card->lock);
	if (card->Active < 0)
		goto out_unlock;
	page = &card->mm_pages[card->Active];

	while (page->headcnt < page->cnt) {
		struct bio *bio = page->bio;
		struct mm_dma_desc *desc = &page->desc[page->headcnt];
		int control = le32_to_cpu(desc->sem_control_bits);
		int last = 0;
		int idx;

		if (!(control & DMASCR_DMA_COMPLETE)) {
			control = dma_status;
			last = 1;
		}
		page->headcnt++;
		idx = page->idx;
		page->idx++;
		if (page->idx >= bio->bi_vcnt) {
			page->bio = bio->bi_next;
			if (page->bio)
				page->idx = page->bio->bi_idx;
		}

		pci_unmap_page(card->dev, desc->data_dma_handle,
			       bio_iovec_idx(bio, idx)->bv_len,
				 (control & DMASCR_TRANSFER_READ) ?
				PCI_DMA_TODEVICE : PCI_DMA_FROMDEVICE);
		if (control & DMASCR_HARD_ERROR) {
			/* error */
			clear_bit(BIO_UPTODATE, &bio->bi_flags);
			dev_printk(KERN_WARNING, &card->dev->dev,
				"I/O error on sector %d/%d\n",
				le32_to_cpu(desc->local_addr)>>9,
				le32_to_cpu(desc->transfer_size));
			dump_dmastat(card, control);
		} else if (test_bit(BIO_RW, &bio->bi_rw) &&
			   le32_to_cpu(desc->local_addr) >> 9 ==
				card->init_size) {
			card->init_size += le32_to_cpu(desc->transfer_size) >> 9;
			if (card->init_size >> 1 >= card->mm_size) {
				dev_printk(KERN_INFO, &card->dev->dev,
					"memory now initialised\n");
				set_userbit(card, MEMORY_INITIALIZED, 1);
			}
		}
		if (bio != page->bio) {
			bio->bi_next = return_bio;
			return_bio = bio;
		}

		if (last)
			break;
	}

	if (debug & DEBUG_LED_ON_TRANSFER)
		set_led(card, LED_REMOVE, LED_OFF);

	if (card->check_batteries) {
		card->check_batteries = 0;
		check_batteries(card);
	}
	if (page->headcnt >= page->cnt) {
		reset_page(page);
		card->Active = -1;
		activate(card);
	} else {
		/* haven't finished with this one yet */
		pr_debug("do some more\n");
		mm_start_io(card);
	}
 out_unlock:
	spin_unlock_bh(&card->lock);

	while (return_bio) {
		struct bio *bio = return_bio;

		return_bio = bio->bi_next;
		bio->bi_next = NULL;
		bio_endio(bio, 0);
	}
}

static int mm_make_request(struct request_queue *q, struct bio *bio)
{
	struct cardinfo *card = q->queuedata;
	pr_debug("mm_make_request %llu %u\n",
		 (unsigned long long)bio->bi_sector, bio->bi_size);

	spin_lock_irq(&card->lock);
	*card->biotail = bio;
	bio->bi_next = NULL;
	card->biotail = &bio->bi_next;
	blk_plug_device(q);
	spin_unlock_irq(&card->lock);

	return 0;
}

static irqreturn_t mm_interrupt(int irq, void *__card)
{
	struct cardinfo *card = (struct cardinfo *) __card;
	unsigned int dma_status;
	unsigned short cfg_status;

HW_TRACE(0x30);

	dma_status = le32_to_cpu(readl(card->csr_remap + DMA_STATUS_CTRL));

	if (!(dma_status & (DMASCR_ERROR_MASK | DMASCR_CHAIN_COMPLETE))) {
		/* interrupt wasn't for me ... */
		return IRQ_NONE;
	}

	/* clear COMPLETION interrupts */
	if (card->flags & UM_FLAG_NO_BYTE_STATUS)
		writel(cpu_to_le32(DMASCR_DMA_COMPLETE|DMASCR_CHAIN_COMPLETE),
		       card->csr_remap + DMA_STATUS_CTRL);
	else
		writeb((DMASCR_DMA_COMPLETE|DMASCR_CHAIN_COMPLETE) >> 16,
		       card->csr_remap + DMA_STATUS_CTRL + 2);

	/* log errors and clear interrupt status */
	if (dma_status & DMASCR_ANY_ERR) {
		unsigned int	data_log1, data_log2;
		unsigned int	addr_log1, addr_log2;
		unsigned char	stat, count, syndrome, check;

		stat = readb(card->csr_remap + MEMCTRLCMD_ERRSTATUS);

		data_log1 = le32_to_cpu(readl(card->csr_remap +
						ERROR_DATA_LOG));
		data_log2 = le32_to_cpu(readl(card->csr_remap +
						ERROR_DATA_LOG + 4));
		addr_log1 = le32_to_cpu(readl(card->csr_remap +
						ERROR_ADDR_LOG));
		addr_log2 = readb(card->csr_remap + ERROR_ADDR_LOG + 4);

		count = readb(card->csr_remap + ERROR_COUNT);
		syndrome = readb(card->csr_remap + ERROR_SYNDROME);
		check = readb(card->csr_remap + ERROR_CHECK);

		dump_dmastat(card, dma_status);

		if (stat & 0x01)
			dev_printk(KERN_ERR, &card->dev->dev,
				"Memory access error detected (err count %d)\n",
				count);
		if (stat & 0x02)
			dev_printk(KERN_ERR, &card->dev->dev,
				"Multi-bit EDC error\n");

		dev_printk(KERN_ERR, &card->dev->dev,
			"Fault Address 0x%02x%08x, Fault Data 0x%08x%08x\n",
			addr_log2, addr_log1, data_log2, data_log1);
		dev_printk(KERN_ERR, &card->dev->dev,
			"Fault Check 0x%02x, Fault Syndrome 0x%02x\n",
			check, syndrome);

		writeb(0, card->csr_remap + ERROR_COUNT);
	}

	if (dma_status & DMASCR_PARITY_ERR_REP) {
		dev_printk(KERN_ERR, &card->dev->dev,
			"PARITY ERROR REPORTED\n");
		pci_read_config_word(card->dev, PCI_STATUS, &cfg_status);
		pci_write_config_word(card->dev, PCI_STATUS, cfg_status);
	}

	if (dma_status & DMASCR_PARITY_ERR_DET) {
		dev_printk(KERN_ERR, &card->dev->dev,
			"PARITY ERROR DETECTED\n");
		pci_read_config_word(card->dev, PCI_STATUS, &cfg_status);
		pci_write_config_word(card->dev, PCI_STATUS, cfg_status);
	}

	if (dma_status & DMASCR_SYSTEM_ERR_SIG) {
		dev_printk(KERN_ERR, &card->dev->dev, "SYSTEM ERROR\n");
		pci_read_config_word(card->dev, PCI_STATUS, &cfg_status);
		pci_write_config_word(card->dev, PCI_STATUS, cfg_status);
	}

	if (dma_status & DMASCR_TARGET_ABT) {
		dev_printk(KERN_ERR, &card->dev->dev, "TARGET ABORT\n");
		pci_read_config_word(card->dev, PCI_STATUS, &cfg_status);
		pci_write_config_word(card->dev, PCI_STATUS, cfg_status);
	}

	if (dma_status & DMASCR_MASTER_ABT) {
		dev_printk(KERN_ERR, &card->dev->dev, "MASTER ABORT\n");
		pci_read_config_word(card->dev, PCI_STATUS, &cfg_status);
		pci_write_config_word(card->dev, PCI_STATUS, cfg_status);
	}

	/* and process the DMA descriptors */
	card->dma_status = dma_status;
	tasklet_schedule(&card->tasklet);

HW_TRACE(0x36);

	return IRQ_HANDLED;
}

/*
 * If both batteries are good, no LED
 * If either battery has been warned, solid LED
 * If both batteries are bad, flash the LED quickly
 * If either battery is bad, flash the LED semi quickly
 */
static void set_fault_to_battery_status(struct cardinfo *card)
{
	if (card->battery[0].good && card->battery[1].good)
		set_led(card, LED_FAULT, LED_OFF);
	else if (card->battery[0].warned || card->battery[1].warned)
		set_led(card, LED_FAULT, LED_ON);
	else if (!card->battery[0].good && !card->battery[1].good)
		set_led(card, LED_FAULT, LED_FLASH_7_0);
	else
		set_led(card, LED_FAULT, LED_FLASH_3_5);
}

static void init_battery_timer(void);

static int check_battery(struct cardinfo *card, int battery, int status)
{
	if (status != card->battery[battery].good) {
		card->battery[battery].good = !card->battery[battery].good;
		card->battery[battery].last_change = jiffies;

		if (card->battery[battery].good) {
			dev_printk(KERN_ERR, &card->dev->dev,
				"Battery %d now good\n", battery + 1);
			card->battery[battery].warned = 0;
		} else
			dev_printk(KERN_ERR, &card->dev->dev,
				"Battery %d now FAILED\n", battery + 1);

		return 1;
	} else if (!card->battery[battery].good &&
		   !card->battery[battery].warned &&
		   time_after_eq(jiffies, card->battery[battery].last_change +
				 (HZ * 60 * 60 * 5))) {
		dev_printk(KERN_ERR, &card->dev->dev,
			"Battery %d still FAILED after 5 hours\n", battery + 1);
		card->battery[battery].warned = 1;

		return 1;
	}

	return 0;
}

static void check_batteries(struct cardinfo *card)
{
	/* NOTE: this must *never* be called while the card
	 * is doing (bus-to-card) DMA, or you will need the
	 * reset switch
	 */
	unsigned char status;
	int ret1, ret2;

	status = readb(card->csr_remap + MEMCTRLSTATUS_BATTERY);
	if (debug & DEBUG_BATTERY_POLLING)
		dev_printk(KERN_DEBUG, &card->dev->dev,
			"checking battery status, 1 = %s, 2 = %s\n",
		       (status & BATTERY_1_FAILURE) ? "FAILURE" : "OK",
		       (status & BATTERY_2_FAILURE) ? "FAILURE" : "OK");

	ret1 = check_battery(card, 0, !(status & BATTERY_1_FAILURE));
	ret2 = check_battery(card, 1, !(status & BATTERY_2_FAILURE));

	if (ret1 || ret2)
		set_fault_to_battery_status(card);
}

static void check_all_batteries(unsigned long ptr)
{
	int i;

	for (i = 0; i < num_cards; i++)
		if (!(cards[i].flags & UM_FLAG_NO_BATT)) {
			struct cardinfo *card = &cards[i];
			spin_lock_bh(&card->lock);
			if (card->Active >= 0)
				card->check_batteries = 1;
			else
				check_batteries(card);
			spin_unlock_bh(&card->lock);
		}

	init_battery_timer();
}

static void init_battery_timer(void)
{
	init_timer(&battery_timer);
	battery_timer.function = check_all_batteries;
	battery_timer.expires = jiffies + (HZ * 60);
	add_timer(&battery_timer);
}

static void del_battery_timer(void)
{
	del_timer(&battery_timer);
}

/*
 * Note no locks taken out here.  In a worst case scenario, we could drop
 * a chunk of system memory.  But that should never happen, since validation
 * happens at open or mount time, when locks are held.
 *
 *	That's crap, since doing that while some partitions are opened
 * or mounted will give you really nasty results.
 */
static int mm_revalidate(struct gendisk *disk)
{
	struct cardinfo *card = disk->private_data;
	set_capacity(disk, card->mm_size << 1);
	return 0;
}

static int mm_getgeo(struct block_device *bdev, struct hd_geometry *geo)
{
	struct cardinfo *card = bdev->bd_disk->private_data;
	int size = card->mm_size * (1024 / MM_HARDSECT);

	/*
	 * get geometry: we have to fake one...  trim the size to a
	 * multiple of 2048 (1M): tell we have 32 sectors, 64 heads,
	 * whatever cylinders.
	 */
	geo->heads     = 64;
	geo->sectors   = 32;
	geo->cylinders = size / (geo->heads * geo->sectors);
	return 0;
}

/*
 * Future support for removable devices
 */
static int mm_check_change(struct gendisk *disk)
{
/*  struct cardinfo *dev = disk->private_data; */
	return 0;
}

static struct block_device_operations mm_fops = {
	.owner		= THIS_MODULE,
	.getgeo		= mm_getgeo,
	.revalidate_disk = mm_revalidate,
	.media_changed	= mm_check_change,
};

static int __devinit mm_pci_probe(struct pci_dev *dev,
				const struct pci_device_id *id)
{
	int ret = -ENODEV;
	struct cardinfo *card = &cards[num_cards];
	unsigned char	mem_present;
	unsigned char	batt_status;
	unsigned int	saved_bar, data;
	unsigned long	csr_base;
	unsigned long	csr_len;
	int		magic_number;
	static int	printed_version;

	if (!printed_version++)
		printk(KERN_INFO DRIVER_VERSION " : " DRIVER_DESC "\n");

	ret = pci_enable_device(dev);
	if (ret)
		return ret;

	pci_write_config_byte(dev, PCI_LATENCY_TIMER, 0xF8);
	pci_set_master(dev);

	card->dev         = dev;

	csr_base = pci_resource_start(dev, 0);
	csr_len  = pci_resource_len(dev, 0);
	if (!csr_base || !csr_len)
		return -ENODEV;

	dev_printk(KERN_INFO, &dev->dev,
	  "Micro Memory(tm) controller found (PCI Mem Module (Battery Backup))\n");

	if (pci_set_dma_mask(dev, DMA_BIT_MASK(64)) &&
	    pci_set_dma_mask(dev, DMA_32BIT_MASK)) {
		dev_printk(KERN_WARNING, &dev->dev, "NO suitable DMA found\n");
		return  -ENOMEM;
	}

	ret = pci_request_regions(dev, DRIVER_NAME);
	if (ret) {
		dev_printk(KERN_ERR, &card->dev->dev,
			"Unable to request memory region\n");
		goto failed_req_csr;
	}

	card->csr_remap = ioremap_nocache(csr_base, csr_len);
	if (!card->csr_remap) {
		dev_printk(KERN_ERR, &card->dev->dev,
			"Unable to remap memory region\n");
		ret = -ENOMEM;

		goto failed_remap_csr;
	}

	dev_printk(KERN_INFO, &card->dev->dev,
		"CSR 0x%08lx -> 0x%p (0x%lx)\n",
	       csr_base, card->csr_remap, csr_len);

	switch (card->dev->device) {
	case 0x5415:
		card->flags |= UM_FLAG_NO_BYTE_STATUS | UM_FLAG_NO_BATTREG;
		magic_number = 0x59;
		break;

	case 0x5425:
		card->flags |= UM_FLAG_NO_BYTE_STATUS;
		magic_number = 0x5C;
		break;

	case 0x6155:
		card->flags |= UM_FLAG_NO_BYTE_STATUS |
				UM_FLAG_NO_BATTREG | UM_FLAG_NO_BATT;
		magic_number = 0x99;
		break;

	default:
		magic_number = 0x100;
		break;
	}

	if (readb(card->csr_remap + MEMCTRLSTATUS_MAGIC) != magic_number) {
		dev_printk(KERN_ERR, &card->dev->dev, "Magic number invalid\n");
		ret = -ENOMEM;
		goto failed_magic;
	}

	card->mm_pages[0].desc = pci_alloc_consistent(card->dev,
						PAGE_SIZE * 2,
						&card->mm_pages[0].page_dma);
	card->mm_pages[1].desc = pci_alloc_consistent(card->dev,
						PAGE_SIZE * 2,
						&card->mm_pages[1].page_dma);
	if (card->mm_pages[0].desc == NULL ||
	    card->mm_pages[1].desc == NULL) {
		dev_printk(KERN_ERR, &card->dev->dev, "alloc failed\n");
		goto failed_alloc;
	}
	reset_page(&card->mm_pages[0]);
	reset_page(&card->mm_pages[1]);
	card->Ready = 0;	/* page 0 is ready */
	card->Active = -1;	/* no page is active */
	card->bio = NULL;
	card->biotail = &card->bio;

	card->queue = blk_alloc_queue(GFP_KERNEL);
	if (!card->queue)
		goto failed_alloc;

	blk_queue_make_request(card->queue, mm_make_request);
	card->queue->queuedata = card;
	card->queue->unplug_fn = mm_unplug_device;

	tasklet_init(&card->tasklet, process_page, (unsigned long)card);

	card->check_batteries = 0;

	mem_present = readb(card->csr_remap + MEMCTRLSTATUS_MEMORY);
	switch (mem_present) {
	case MEM_128_MB:
		card->mm_size = 1024 * 128;
		break;
	case MEM_256_MB:
		card->mm_size = 1024 * 256;
		break;
	case MEM_512_MB:
		card->mm_size = 1024 * 512;
		break;
	case MEM_1_GB:
		card->mm_size = 1024 * 1024;
		break;
	case MEM_2_GB:
		card->mm_size = 1024 * 2048;
		break;
	default:
		card->mm_size = 0;
		break;
	}

	/* Clear the LED's we control */
	set_led(card, LED_REMOVE, LED_OFF);
	set_led(card, LED_FAULT, LED_OFF);

	batt_status = readb(card->csr_remap + MEMCTRLSTATUS_BATTERY);

	card->battery[0].good = !(batt_status & BATTERY_1_FAILURE);
	card->battery[1].good = !(batt_status & BATTERY_2_FAILURE);
	card->battery[0].last_change = card->battery[1].last_change = jiffies;

	if (card->flags & UM_FLAG_NO_BATT)
		dev_printk(KERN_INFO, &card->dev->dev,
			"Size %d KB\n", card->mm_size);
	else {
		dev_printk(KERN_INFO, &card->dev->dev,
			"Size %d KB, Battery 1 %s (%s), Battery 2 %s (%s)\n",
		       card->mm_size,
		       batt_status & BATTERY_1_DISABLED ? "Disabled" : "Enabled",
		       card->battery[0].good ? "OK" : "FAILURE",
		       batt_status & BATTERY_2_DISABLED ? "Disabled" : "Enabled",
		       card->battery[1].good ? "OK" : "FAILURE");

		set_fault_to_battery_status(card);
	}

	pci_read_config_dword(dev, PCI_BASE_ADDRESS_1, &saved_bar);
	data = 0xffffffff;
	pci_write_config_dword(dev, PCI_BASE_ADDRESS_1, data);
	pci_read_config_dword(dev, PCI_BASE_ADDRESS_1, &data);
	pci_write_config_dword(dev, PCI_BASE_ADDRESS_1, saved_bar);
	data &= 0xfffffff0;
	data = ~data;
	data += 1;

	if (request_irq(dev->irq, mm_interrupt, IRQF_SHARED, DRIVER_NAME,
			card)) {
		dev_printk(KERN_ERR, &card->dev->dev,
			"Unable to allocate IRQ\n");
		ret = -ENODEV;
		goto failed_req_irq;
	}

	dev_printk(KERN_INFO, &card->dev->dev,
		"Window size %d bytes, IRQ %d\n", data, dev->irq);

	spin_lock_init(&card->lock);

	pci_set_drvdata(dev, card);

	if (pci_write_cmd != 0x0F) 	/* If not Memory Write & Invalidate */
		pci_write_cmd = 0x07;	/* then Memory Write command */

	if (pci_write_cmd & 0x08) { /* use Memory Write and Invalidate */
		unsigned short cfg_command;
		pci_read_config_word(dev, PCI_COMMAND, &cfg_command);
		cfg_command |= 0x10; /* Memory Write & Invalidate Enable */
		pci_write_config_word(dev, PCI_COMMAND, cfg_command);
	}
	pci_cmds = (pci_read_cmd << 28) | (pci_write_cmd << 24);

	num_cards++;

	if (!get_userbit(card, MEMORY_INITIALIZED)) {
		dev_printk(KERN_INFO, &card->dev->dev,
		  "memory NOT initialized. Consider over-writing whole device.\n");
		card->init_size = 0;
	} else {
		dev_printk(KERN_INFO, &card->dev->dev,
			"memory already initialized\n");
		card->init_size = card->mm_size;
	}

	/* Enable ECC */
	writeb(EDC_STORE_CORRECT, card->csr_remap + MEMCTRLCMD_ERRCTRL);

	return 0;

 failed_req_irq:
 failed_alloc:
	if (card->mm_pages[0].desc)
		pci_free_consistent(card->dev, PAGE_SIZE*2,
				    card->mm_pages[0].desc,
				    card->mm_pages[0].page_dma);
	if (card->mm_pages[1].desc)
		pci_free_consistent(card->dev, PAGE_SIZE*2,
				    card->mm_pages[1].desc,
				    card->mm_pages[1].page_dma);
 failed_magic:
	iounmap(card->csr_remap);
 failed_remap_csr:
	pci_release_regions(dev);
 failed_req_csr:

	return ret;
}

static void mm_pci_remove(struct pci_dev *dev)
{
	struct cardinfo *card = pci_get_drvdata(dev);

	tasklet_kill(&card->tasklet);
	free_irq(dev->irq, card);
	iounmap(card->csr_remap);

	if (card->mm_pages[0].desc)
		pci_free_consistent(card->dev, PAGE_SIZE*2,
				    card->mm_pages[0].desc,
				    card->mm_pages[0].page_dma);
	if (card->mm_pages[1].desc)
		pci_free_consistent(card->dev, PAGE_SIZE*2,
				    card->mm_pages[1].desc,
				    card->mm_pages[1].page_dma);
	blk_cleanup_queue(card->queue);

	pci_release_regions(dev);
	pci_disable_device(dev);
}

static const struct pci_device_id mm_pci_ids[] = {
    {PCI_DEVICE(PCI_VENDOR_ID_MICRO_MEMORY, PCI_DEVICE_ID_MICRO_MEMORY_5415CN)},
    {PCI_DEVICE(PCI_VENDOR_ID_MICRO_MEMORY, PCI_DEVICE_ID_MICRO_MEMORY_5425CN)},
    {PCI_DEVICE(PCI_VENDOR_ID_MICRO_MEMORY, PCI_DEVICE_ID_MICRO_MEMORY_6155)},
    {
	.vendor	=	0x8086,
	.device	=	0xB555,
	.subvendor =	0x1332,
	.subdevice =	0x5460,
	.class =	0x050000,
	.class_mask =	0,
    }, { /* end: all zeroes */ }
};

MODULE_DEVICE_TABLE(pci, mm_pci_ids);

static struct pci_driver mm_pci_driver = {
	.name		= DRIVER_NAME,
	.id_table	= mm_pci_ids,
	.probe		= mm_pci_probe,
	.remove		= mm_pci_remove,
};

static int __init mm_init(void)
{
	int retval, i;
	int err;

	retval = pci_register_driver(&mm_pci_driver);
	if (retval)
		return -ENOMEM;

	err = major_nr = register_blkdev(0, DRIVER_NAME);
	if (err < 0) {
		pci_unregister_driver(&mm_pci_driver);
		return -EIO;
	}

	for (i = 0; i < num_cards; i++) {
		mm_gendisk[i] = alloc_disk(1 << MM_SHIFT);
		if (!mm_gendisk[i])
			goto out;
	}

	for (i = 0; i < num_cards; i++) {
		struct gendisk *disk = mm_gendisk[i];
		sprintf(disk->disk_name, "umem%c", 'a'+i);
		spin_lock_init(&cards[i].lock);
		disk->major = major_nr;
		disk->first_minor  = i << MM_SHIFT;
		disk->fops = &mm_fops;
		disk->private_data = &cards[i];
		disk->queue = cards[i].queue;
		set_capacity(disk, cards[i].mm_size << 1);
		add_disk(disk);
	}

	init_battery_timer();
	printk(KERN_INFO "MM: desc_per_page = %ld\n", DESC_PER_PAGE);
/* printk("mm_init: Done. 10-19-01 9:00\n"); */
	return 0;

out:
	pci_unregister_driver(&mm_pci_driver);
	unregister_blkdev(major_nr, DRIVER_NAME);
	while (i--)
		put_disk(mm_gendisk[i]);
	return -ENOMEM;
}

static void __exit mm_cleanup(void)
{
	int i;

	del_battery_timer();

	for (i = 0; i < num_cards ; i++) {
		del_gendisk(mm_gendisk[i]);
		put_disk(mm_gendisk[i]);
	}

	pci_unregister_driver(&mm_pci_driver);

	unregister_blkdev(major_nr, DRIVER_NAME);
}

module_init(mm_init);
module_exit(mm_cleanup);

MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");