summaryrefslogtreecommitdiffstats
path: root/drivers/misc/genwqe/card_utils.c
blob: 2e1c4d2905e81840e277834ff579dbc6e4161eb1 (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
// SPDX-License-Identifier: GPL-2.0-only
/**
 * IBM Accelerator Family 'GenWQE'
 *
 * (C) Copyright IBM Corp. 2013
 *
 * Author: Frank Haverkamp <haver@linux.vnet.ibm.com>
 * Author: Joerg-Stephan Vogt <jsvogt@de.ibm.com>
 * Author: Michael Jung <mijung@gmx.net>
 * Author: Michael Ruettger <michael@ibmra.de>
 */

/*
 * Miscelanous functionality used in the other GenWQE driver parts.
 */

#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/vmalloc.h>
#include <linux/page-flags.h>
#include <linux/scatterlist.h>
#include <linux/hugetlb.h>
#include <linux/iommu.h>
#include <linux/pci.h>
#include <linux/dma-mapping.h>
#include <linux/ctype.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/delay.h>
#include <asm/pgtable.h>

#include "genwqe_driver.h"
#include "card_base.h"
#include "card_ddcb.h"

/**
 * __genwqe_writeq() - Write 64-bit register
 * @cd:	        genwqe device descriptor
 * @byte_offs:  byte offset within BAR
 * @val:        64-bit value
 *
 * Return: 0 if success; < 0 if error
 */
int __genwqe_writeq(struct genwqe_dev *cd, u64 byte_offs, u64 val)
{
	struct pci_dev *pci_dev = cd->pci_dev;

	if (cd->err_inject & GENWQE_INJECT_HARDWARE_FAILURE)
		return -EIO;

	if (cd->mmio == NULL)
		return -EIO;

	if (pci_channel_offline(pci_dev))
		return -EIO;

	__raw_writeq((__force u64)cpu_to_be64(val), cd->mmio + byte_offs);
	return 0;
}

/**
 * __genwqe_readq() - Read 64-bit register
 * @cd:         genwqe device descriptor
 * @byte_offs:  offset within BAR
 *
 * Return: value from register
 */
u64 __genwqe_readq(struct genwqe_dev *cd, u64 byte_offs)
{
	if (cd->err_inject & GENWQE_INJECT_HARDWARE_FAILURE)
		return 0xffffffffffffffffull;

	if ((cd->err_inject & GENWQE_INJECT_GFIR_FATAL) &&
	    (byte_offs == IO_SLC_CFGREG_GFIR))
		return 0x000000000000ffffull;

	if ((cd->err_inject & GENWQE_INJECT_GFIR_INFO) &&
	    (byte_offs == IO_SLC_CFGREG_GFIR))
		return 0x00000000ffff0000ull;

	if (cd->mmio == NULL)
		return 0xffffffffffffffffull;

	return be64_to_cpu((__force __be64)__raw_readq(cd->mmio + byte_offs));
}

/**
 * __genwqe_writel() - Write 32-bit register
 * @cd:	        genwqe device descriptor
 * @byte_offs:  byte offset within BAR
 * @val:        32-bit value
 *
 * Return: 0 if success; < 0 if error
 */
int __genwqe_writel(struct genwqe_dev *cd, u64 byte_offs, u32 val)
{
	struct pci_dev *pci_dev = cd->pci_dev;

	if (cd->err_inject & GENWQE_INJECT_HARDWARE_FAILURE)
		return -EIO;

	if (cd->mmio == NULL)
		return -EIO;

	if (pci_channel_offline(pci_dev))
		return -EIO;

	__raw_writel((__force u32)cpu_to_be32(val), cd->mmio + byte_offs);
	return 0;
}

/**
 * __genwqe_readl() - Read 32-bit register
 * @cd:         genwqe device descriptor
 * @byte_offs:  offset within BAR
 *
 * Return: Value from register
 */
u32 __genwqe_readl(struct genwqe_dev *cd, u64 byte_offs)
{
	if (cd->err_inject & GENWQE_INJECT_HARDWARE_FAILURE)
		return 0xffffffff;

	if (cd->mmio == NULL)
		return 0xffffffff;

	return be32_to_cpu((__force __be32)__raw_readl(cd->mmio + byte_offs));
}

/**
 * genwqe_read_app_id() - Extract app_id
 *
 * app_unitcfg need to be filled with valid data first
 */
int genwqe_read_app_id(struct genwqe_dev *cd, char *app_name, int len)
{
	int i, j;
	u32 app_id = (u32)cd->app_unitcfg;

	memset(app_name, 0, len);
	for (i = 0, j = 0; j < min(len, 4); j++) {
		char ch = (char)((app_id >> (24 - j*8)) & 0xff);

		if (ch == ' ')
			continue;
		app_name[i++] = isprint(ch) ? ch : 'X';
	}
	return i;
}

/**
 * genwqe_init_crc32() - Prepare a lookup table for fast crc32 calculations
 *
 * Existing kernel functions seem to use a different polynom,
 * therefore we could not use them here.
 *
 * Genwqe's Polynomial = 0x20044009
 */
#define CRC32_POLYNOMIAL	0x20044009
static u32 crc32_tab[256];	/* crc32 lookup table */

void genwqe_init_crc32(void)
{
	int i, j;
	u32 crc;

	for (i = 0;  i < 256;  i++) {
		crc = i << 24;
		for (j = 0;  j < 8;  j++) {
			if (crc & 0x80000000)
				crc = (crc << 1) ^ CRC32_POLYNOMIAL;
			else
				crc = (crc << 1);
		}
		crc32_tab[i] = crc;
	}
}

/**
 * genwqe_crc32() - Generate 32-bit crc as required for DDCBs
 * @buff:       pointer to data buffer
 * @len:        length of data for calculation
 * @init:       initial crc (0xffffffff at start)
 *
 * polynomial = x^32 * + x^29 + x^18 + x^14 + x^3 + 1 (0x20044009)

 * Example: 4 bytes 0x01 0x02 0x03 0x04 with init=0xffffffff should
 * result in a crc32 of 0xf33cb7d3.
 *
 * The existing kernel crc functions did not cover this polynom yet.
 *
 * Return: crc32 checksum.
 */
u32 genwqe_crc32(u8 *buff, size_t len, u32 init)
{
	int i;
	u32 crc;

	crc = init;
	while (len--) {
		i = ((crc >> 24) ^ *buff++) & 0xFF;
		crc = (crc << 8) ^ crc32_tab[i];
	}
	return crc;
}

void *__genwqe_alloc_consistent(struct genwqe_dev *cd, size_t size,
			       dma_addr_t *dma_handle)
{
	if (get_order(size) >= MAX_ORDER)
		return NULL;

	return dma_alloc_coherent(&cd->pci_dev->dev, size, dma_handle,
				  GFP_KERNEL);
}

void __genwqe_free_consistent(struct genwqe_dev *cd, size_t size,
			     void *vaddr, dma_addr_t dma_handle)
{
	if (vaddr == NULL)
		return;

	dma_free_coherent(&cd->pci_dev->dev, size, vaddr, dma_handle);
}

static void genwqe_unmap_pages(struct genwqe_dev *cd, dma_addr_t *dma_list,
			      int num_pages)
{
	int i;
	struct pci_dev *pci_dev = cd->pci_dev;

	for (i = 0; (i < num_pages) && (dma_list[i] != 0x0); i++) {
		pci_unmap_page(pci_dev, dma_list[i],
			       PAGE_SIZE, PCI_DMA_BIDIRECTIONAL);
		dma_list[i] = 0x0;
	}
}

static int genwqe_map_pages(struct genwqe_dev *cd,
			   struct page **page_list, int num_pages,
			   dma_addr_t *dma_list)
{
	int i;
	struct pci_dev *pci_dev = cd->pci_dev;

	/* establish DMA mapping for requested pages */
	for (i = 0; i < num_pages; i++) {
		dma_addr_t daddr;

		dma_list[i] = 0x0;
		daddr = pci_map_page(pci_dev, page_list[i],
				     0,	 /* map_offs */
				     PAGE_SIZE,
				     PCI_DMA_BIDIRECTIONAL);  /* FIXME rd/rw */

		if (pci_dma_mapping_error(pci_dev, daddr)) {
			dev_err(&pci_dev->dev,
				"[%s] err: no dma addr daddr=%016llx!\n",
				__func__, (long long)daddr);
			goto err;
		}

		dma_list[i] = daddr;
	}
	return 0;

 err:
	genwqe_unmap_pages(cd, dma_list, num_pages);
	return -EIO;
}

static int genwqe_sgl_size(int num_pages)
{
	int len, num_tlb = num_pages / 7;

	len = sizeof(struct sg_entry) * (num_pages+num_tlb + 1);
	return roundup(len, PAGE_SIZE);
}

/**
 * genwqe_alloc_sync_sgl() - Allocate memory for sgl and overlapping pages
 *
 * Allocates memory for sgl and overlapping pages. Pages which might
 * overlap other user-space memory blocks are being cached for DMAs,
 * such that we do not run into syncronization issues. Data is copied
 * from user-space into the cached pages.
 */
int genwqe_alloc_sync_sgl(struct genwqe_dev *cd, struct genwqe_sgl *sgl,
			  void __user *user_addr, size_t user_size, int write)
{
	int ret = -ENOMEM;
	struct pci_dev *pci_dev = cd->pci_dev;

	sgl->fpage_offs = offset_in_page((unsigned long)user_addr);
	sgl->fpage_size = min_t(size_t, PAGE_SIZE-sgl->fpage_offs, user_size);
	sgl->nr_pages = DIV_ROUND_UP(sgl->fpage_offs + user_size, PAGE_SIZE);
	sgl->lpage_size = (user_size - sgl->fpage_size) % PAGE_SIZE;

	dev_dbg(&pci_dev->dev, "[%s] uaddr=%p usize=%8ld nr_pages=%ld fpage_offs=%lx fpage_size=%ld lpage_size=%ld\n",
		__func__, user_addr, user_size, sgl->nr_pages,
		sgl->fpage_offs, sgl->fpage_size, sgl->lpage_size);

	sgl->user_addr = user_addr;
	sgl->user_size = user_size;
	sgl->write = write;
	sgl->sgl_size = genwqe_sgl_size(sgl->nr_pages);

	if (get_order(sgl->sgl_size) > MAX_ORDER) {
		dev_err(&pci_dev->dev,
			"[%s] err: too much memory requested!\n", __func__);
		return ret;
	}

	sgl->sgl = __genwqe_alloc_consistent(cd, sgl->sgl_size,
					     &sgl->sgl_dma_addr);
	if (sgl->sgl == NULL) {
		dev_err(&pci_dev->dev,
			"[%s] err: no memory available!\n", __func__);
		return ret;
	}

	/* Only use buffering on incomplete pages */
	if ((sgl->fpage_size != 0) && (sgl->fpage_size != PAGE_SIZE)) {
		sgl->fpage = __genwqe_alloc_consistent(cd, PAGE_SIZE,
						       &sgl->fpage_dma_addr);
		if (sgl->fpage == NULL)
			goto err_out;

		/* Sync with user memory */
		if (copy_from_user(sgl->fpage + sgl->fpage_offs,
				   user_addr, sgl->fpage_size)) {
			ret = -EFAULT;
			goto err_out;
		}
	}
	if (sgl->lpage_size != 0) {
		sgl->lpage = __genwqe_alloc_consistent(cd, PAGE_SIZE,
						       &sgl->lpage_dma_addr);
		if (sgl->lpage == NULL)
			goto err_out1;

		/* Sync with user memory */
		if (copy_from_user(sgl->lpage, user_addr + user_size -
				   sgl->lpage_size, sgl->lpage_size)) {
			ret = -EFAULT;
			goto err_out2;
		}
	}
	return 0;

 err_out2:
	__genwqe_free_consistent(cd, PAGE_SIZE, sgl->lpage,
				 sgl->lpage_dma_addr);
	sgl->lpage = NULL;
	sgl->lpage_dma_addr = 0;
 err_out1:
	__genwqe_free_consistent(cd, PAGE_SIZE, sgl->fpage,
				 sgl->fpage_dma_addr);
	sgl->fpage = NULL;
	sgl->fpage_dma_addr = 0;
 err_out:
	__genwqe_free_consistent(cd, sgl->sgl_size, sgl->sgl,
				 sgl->sgl_dma_addr);
	sgl->sgl = NULL;
	sgl->sgl_dma_addr = 0;
	sgl->sgl_size = 0;

	return ret;
}

int genwqe_setup_sgl(struct genwqe_dev *cd, struct genwqe_sgl *sgl,
		     dma_addr_t *dma_list)
{
	int i = 0, j = 0, p;
	unsigned long dma_offs, map_offs;
	dma_addr_t prev_daddr = 0;
	struct sg_entry *s, *last_s = NULL;
	size_t size = sgl->user_size;

	dma_offs = 128;		/* next block if needed/dma_offset */
	map_offs = sgl->fpage_offs; /* offset in first page */

	s = &sgl->sgl[0];	/* first set of 8 entries */
	p = 0;			/* page */
	while (p < sgl->nr_pages) {
		dma_addr_t daddr;
		unsigned int size_to_map;

		/* always write the chaining entry, cleanup is done later */
		j = 0;
		s[j].target_addr = cpu_to_be64(sgl->sgl_dma_addr + dma_offs);
		s[j].len	 = cpu_to_be32(128);
		s[j].flags	 = cpu_to_be32(SG_CHAINED);
		j++;

		while (j < 8) {
			/* DMA mapping for requested page, offs, size */
			size_to_map = min(size, PAGE_SIZE - map_offs);

			if ((p == 0) && (sgl->fpage != NULL)) {
				daddr = sgl->fpage_dma_addr + map_offs;

			} else if ((p == sgl->nr_pages - 1) &&
				   (sgl->lpage != NULL)) {
				daddr = sgl->lpage_dma_addr;
			} else {
				daddr = dma_list[p] + map_offs;
			}

			size -= size_to_map;
			map_offs = 0;

			if (prev_daddr == daddr) {
				u32 prev_len = be32_to_cpu(last_s->len);

				/* pr_info("daddr combining: "
					"%016llx/%08x -> %016llx\n",
					prev_daddr, prev_len, daddr); */

				last_s->len = cpu_to_be32(prev_len +
							  size_to_map);

				p++; /* process next page */
				if (p == sgl->nr_pages)
					goto fixup;  /* nothing to do */

				prev_daddr = daddr + size_to_map;
				continue;
			}

			/* start new entry */
			s[j].target_addr = cpu_to_be64(daddr);
			s[j].len	 = cpu_to_be32(size_to_map);
			s[j].flags	 = cpu_to_be32(SG_DATA);
			prev_daddr = daddr + size_to_map;
			last_s = &s[j];
			j++;

			p++;	/* process next page */
			if (p == sgl->nr_pages)
				goto fixup;  /* nothing to do */
		}
		dma_offs += 128;
		s += 8;		/* continue 8 elements further */
	}
 fixup:
	if (j == 1) {		/* combining happened on last entry! */
		s -= 8;		/* full shift needed on previous sgl block */
		j =  7;		/* shift all elements */
	}

	for (i = 0; i < j; i++)	/* move elements 1 up */
		s[i] = s[i + 1];

	s[i].target_addr = cpu_to_be64(0);
	s[i].len	 = cpu_to_be32(0);
	s[i].flags	 = cpu_to_be32(SG_END_LIST);
	return 0;
}

/**
 * genwqe_free_sync_sgl() - Free memory for sgl and overlapping pages
 *
 * After the DMA transfer has been completed we free the memory for
 * the sgl and the cached pages. Data is being transferred from cached
 * pages into user-space buffers.
 */
int genwqe_free_sync_sgl(struct genwqe_dev *cd, struct genwqe_sgl *sgl)
{
	int rc = 0;
	size_t offset;
	unsigned long res;
	struct pci_dev *pci_dev = cd->pci_dev;

	if (sgl->fpage) {
		if (sgl->write) {
			res = copy_to_user(sgl->user_addr,
				sgl->fpage + sgl->fpage_offs, sgl->fpage_size);
			if (res) {
				dev_err(&pci_dev->dev,
					"[%s] err: copying fpage! (res=%lu)\n",
					__func__, res);
				rc = -EFAULT;
			}
		}
		__genwqe_free_consistent(cd, PAGE_SIZE, sgl->fpage,
					 sgl->fpage_dma_addr);
		sgl->fpage = NULL;
		sgl->fpage_dma_addr = 0;
	}
	if (sgl->lpage) {
		if (sgl->write) {
			offset = sgl->user_size - sgl->lpage_size;
			res = copy_to_user(sgl->user_addr + offset, sgl->lpage,
					   sgl->lpage_size);
			if (res) {
				dev_err(&pci_dev->dev,
					"[%s] err: copying lpage! (res=%lu)\n",
					__func__, res);
				rc = -EFAULT;
			}
		}
		__genwqe_free_consistent(cd, PAGE_SIZE, sgl->lpage,
					 sgl->lpage_dma_addr);
		sgl->lpage = NULL;
		sgl->lpage_dma_addr = 0;
	}
	__genwqe_free_consistent(cd, sgl->sgl_size, sgl->sgl,
				 sgl->sgl_dma_addr);

	sgl->sgl = NULL;
	sgl->sgl_dma_addr = 0x0;
	sgl->sgl_size = 0;
	return rc;
}

/**
 * genwqe_free_user_pages() - Give pinned pages back
 *
 * Documentation of get_user_pages is in mm/gup.c:
 *
 * If the page is written to, set_page_dirty (or set_page_dirty_lock,
 * as appropriate) must be called after the page is finished with, and
 * before put_page is called.
 */
static int genwqe_free_user_pages(struct page **page_list,
			unsigned int nr_pages, int dirty)
{
	unsigned int i;

	for (i = 0; i < nr_pages; i++) {
		if (page_list[i] != NULL) {
			if (dirty)
				set_page_dirty_lock(page_list[i]);
			put_page(page_list[i]);
		}
	}
	return 0;
}

/**
 * genwqe_user_vmap() - Map user-space memory to virtual kernel memory
 * @cd:         pointer to genwqe device
 * @m:          mapping params
 * @uaddr:      user virtual address
 * @size:       size of memory to be mapped
 *
 * We need to think about how we could speed this up. Of course it is
 * not a good idea to do this over and over again, like we are
 * currently doing it. Nevertheless, I am curious where on the path
 * the performance is spend. Most probably within the memory
 * allocation functions, but maybe also in the DMA mapping code.
 *
 * Restrictions: The maximum size of the possible mapping currently depends
 *               on the amount of memory we can get using kzalloc() for the
 *               page_list and pci_alloc_consistent for the sg_list.
 *               The sg_list is currently itself not scattered, which could
 *               be fixed with some effort. The page_list must be split into
 *               PAGE_SIZE chunks too. All that will make the complicated
 *               code more complicated.
 *
 * Return: 0 if success
 */
int genwqe_user_vmap(struct genwqe_dev *cd, struct dma_mapping *m, void *uaddr,
		     unsigned long size)
{
	int rc = -EINVAL;
	unsigned long data, offs;
	struct pci_dev *pci_dev = cd->pci_dev;

	if ((uaddr == NULL) || (size == 0)) {
		m->size = 0;	/* mark unused and not added */
		return -EINVAL;
	}
	m->u_vaddr = uaddr;
	m->size    = size;

	/* determine space needed for page_list. */
	data = (unsigned long)uaddr;
	offs = offset_in_page(data);
	if (size > ULONG_MAX - PAGE_SIZE - offs) {
		m->size = 0;	/* mark unused and not added */
		return -EINVAL;
	}
	m->nr_pages = DIV_ROUND_UP(offs + size, PAGE_SIZE);

	m->page_list = kcalloc(m->nr_pages,
			       sizeof(struct page *) + sizeof(dma_addr_t),
			       GFP_KERNEL);
	if (!m->page_list) {
		dev_err(&pci_dev->dev, "err: alloc page_list failed\n");
		m->nr_pages = 0;
		m->u_vaddr = NULL;
		m->size = 0;	/* mark unused and not added */
		return -ENOMEM;
	}
	m->dma_list = (dma_addr_t *)(m->page_list + m->nr_pages);

	/* pin user pages in memory */
	rc = get_user_pages_fast(data & PAGE_MASK, /* page aligned addr */
				 m->nr_pages,
				 m->write ? FOLL_WRITE : 0,	/* readable/writable */
				 m->page_list);	/* ptrs to pages */
	if (rc < 0)
		goto fail_get_user_pages;

	/* assumption: get_user_pages can be killed by signals. */
	if (rc < m->nr_pages) {
		genwqe_free_user_pages(m->page_list, rc, m->write);
		rc = -EFAULT;
		goto fail_get_user_pages;
	}

	rc = genwqe_map_pages(cd, m->page_list, m->nr_pages, m->dma_list);
	if (rc != 0)
		goto fail_free_user_pages;

	return 0;

 fail_free_user_pages:
	genwqe_free_user_pages(m->page_list, m->nr_pages, m->write);

 fail_get_user_pages:
	kfree(m->page_list);
	m->page_list = NULL;
	m->dma_list = NULL;
	m->nr_pages = 0;
	m->u_vaddr = NULL;
	m->size = 0;		/* mark unused and not added */
	return rc;
}

/**
 * genwqe_user_vunmap() - Undo mapping of user-space mem to virtual kernel
 *                        memory
 * @cd:         pointer to genwqe device
 * @m:          mapping params
 */
int genwqe_user_vunmap(struct genwqe_dev *cd, struct dma_mapping *m)
{
	struct pci_dev *pci_dev = cd->pci_dev;

	if (!dma_mapping_used(m)) {
		dev_err(&pci_dev->dev, "[%s] err: mapping %p not used!\n",
			__func__, m);
		return -EINVAL;
	}

	if (m->dma_list)
		genwqe_unmap_pages(cd, m->dma_list, m->nr_pages);

	if (m->page_list) {
		genwqe_free_user_pages(m->page_list, m->nr_pages, m->write);

		kfree(m->page_list);
		m->page_list = NULL;
		m->dma_list = NULL;
		m->nr_pages = 0;
	}

	m->u_vaddr = NULL;
	m->size = 0;		/* mark as unused and not added */
	return 0;
}

/**
 * genwqe_card_type() - Get chip type SLU Configuration Register
 * @cd:         pointer to the genwqe device descriptor
 * Return: 0: Altera Stratix-IV 230
 *         1: Altera Stratix-IV 530
 *         2: Altera Stratix-V A4
 *         3: Altera Stratix-V A7
 */
u8 genwqe_card_type(struct genwqe_dev *cd)
{
	u64 card_type = cd->slu_unitcfg;

	return (u8)((card_type & IO_SLU_UNITCFG_TYPE_MASK) >> 20);
}

/**
 * genwqe_card_reset() - Reset the card
 * @cd:         pointer to the genwqe device descriptor
 */
int genwqe_card_reset(struct genwqe_dev *cd)
{
	u64 softrst;
	struct pci_dev *pci_dev = cd->pci_dev;

	if (!genwqe_is_privileged(cd))
		return -ENODEV;

	/* new SL */
	__genwqe_writeq(cd, IO_SLC_CFGREG_SOFTRESET, 0x1ull);
	msleep(1000);
	__genwqe_readq(cd, IO_HSU_FIR_CLR);
	__genwqe_readq(cd, IO_APP_FIR_CLR);
	__genwqe_readq(cd, IO_SLU_FIR_CLR);

	/*
	 * Read-modify-write to preserve the stealth bits
	 *
	 * For SL >= 039, Stealth WE bit allows removing
	 * the read-modify-wrote.
	 * r-m-w may require a mask 0x3C to avoid hitting hard
	 * reset again for error reset (should be 0, chicken).
	 */
	softrst = __genwqe_readq(cd, IO_SLC_CFGREG_SOFTRESET) & 0x3cull;
	__genwqe_writeq(cd, IO_SLC_CFGREG_SOFTRESET, softrst | 0x2ull);

	/* give ERRORRESET some time to finish */
	msleep(50);

	if (genwqe_need_err_masking(cd)) {
		dev_info(&pci_dev->dev,
			 "[%s] masking errors for old bitstreams\n", __func__);
		__genwqe_writeq(cd, IO_SLC_MISC_DEBUG, 0x0aull);
	}
	return 0;
}

int genwqe_read_softreset(struct genwqe_dev *cd)
{
	u64 bitstream;

	if (!genwqe_is_privileged(cd))
		return -ENODEV;

	bitstream = __genwqe_readq(cd, IO_SLU_BITSTREAM) & 0x1;
	cd->softreset = (bitstream == 0) ? 0x8ull : 0xcull;
	return 0;
}

/**
 * genwqe_set_interrupt_capability() - Configure MSI capability structure
 * @cd:         pointer to the device
 * Return: 0 if no error
 */
int genwqe_set_interrupt_capability(struct genwqe_dev *cd, int count)
{
	int rc;

	rc = pci_alloc_irq_vectors(cd->pci_dev, 1, count, PCI_IRQ_MSI);
	if (rc < 0)
		return rc;
	return 0;
}

/**
 * genwqe_reset_interrupt_capability() - Undo genwqe_set_interrupt_capability()
 * @cd:         pointer to the device
 */
void genwqe_reset_interrupt_capability(struct genwqe_dev *cd)
{
	pci_free_irq_vectors(cd->pci_dev);
}

/**
 * set_reg_idx() - Fill array with data. Ignore illegal offsets.
 * @cd:         card device
 * @r:          debug register array
 * @i:          index to desired entry
 * @m:          maximum possible entries
 * @addr:       addr which is read
 * @index:      index in debug array
 * @val:        read value
 */
static int set_reg_idx(struct genwqe_dev *cd, struct genwqe_reg *r,
		       unsigned int *i, unsigned int m, u32 addr, u32 idx,
		       u64 val)
{
	if (WARN_ON_ONCE(*i >= m))
		return -EFAULT;

	r[*i].addr = addr;
	r[*i].idx = idx;
	r[*i].val = val;
	++*i;
	return 0;
}

static int set_reg(struct genwqe_dev *cd, struct genwqe_reg *r,
		   unsigned int *i, unsigned int m, u32 addr, u64 val)
{
	return set_reg_idx(cd, r, i, m, addr, 0, val);
}

int genwqe_read_ffdc_regs(struct genwqe_dev *cd, struct genwqe_reg *regs,
			 unsigned int max_regs, int all)
{
	unsigned int i, j, idx = 0;
	u32 ufir_addr, ufec_addr, sfir_addr, sfec_addr;
	u64 gfir, sluid, appid, ufir, ufec, sfir, sfec;

	/* Global FIR */
	gfir = __genwqe_readq(cd, IO_SLC_CFGREG_GFIR);
	set_reg(cd, regs, &idx, max_regs, IO_SLC_CFGREG_GFIR, gfir);

	/* UnitCfg for SLU */
	sluid = __genwqe_readq(cd, IO_SLU_UNITCFG); /* 0x00000000 */
	set_reg(cd, regs, &idx, max_regs, IO_SLU_UNITCFG, sluid);

	/* UnitCfg for APP */
	appid = __genwqe_readq(cd, IO_APP_UNITCFG); /* 0x02000000 */
	set_reg(cd, regs, &idx, max_regs, IO_APP_UNITCFG, appid);

	/* Check all chip Units */
	for (i = 0; i < GENWQE_MAX_UNITS; i++) {

		/* Unit FIR */
		ufir_addr = (i << 24) | 0x008;
		ufir = __genwqe_readq(cd, ufir_addr);
		set_reg(cd, regs, &idx, max_regs, ufir_addr, ufir);

		/* Unit FEC */
		ufec_addr = (i << 24) | 0x018;
		ufec = __genwqe_readq(cd, ufec_addr);
		set_reg(cd, regs, &idx, max_regs, ufec_addr, ufec);

		for (j = 0; j < 64; j++) {
			/* wherever there is a primary 1, read the 2ndary */
			if (!all && (!(ufir & (1ull << j))))
				continue;

			sfir_addr = (i << 24) | (0x100 + 8 * j);
			sfir = __genwqe_readq(cd, sfir_addr);
			set_reg(cd, regs, &idx, max_regs, sfir_addr, sfir);

			sfec_addr = (i << 24) | (0x300 + 8 * j);
			sfec = __genwqe_readq(cd, sfec_addr);
			set_reg(cd, regs, &idx, max_regs, sfec_addr, sfec);
		}
	}

	/* fill with invalid data until end */
	for (i = idx; i < max_regs; i++) {
		regs[i].addr = 0xffffffff;
		regs[i].val = 0xffffffffffffffffull;
	}
	return idx;
}

/**
 * genwqe_ffdc_buff_size() - Calculates the number of dump registers
 */
int genwqe_ffdc_buff_size(struct genwqe_dev *cd, int uid)
{
	int entries = 0, ring, traps, traces, trace_entries;
	u32 eevptr_addr, l_addr, d_len, d_type;
	u64 eevptr, val, addr;

	eevptr_addr = GENWQE_UID_OFFS(uid) | IO_EXTENDED_ERROR_POINTER;
	eevptr = __genwqe_readq(cd, eevptr_addr);

	if ((eevptr != 0x0) && (eevptr != -1ull)) {
		l_addr = GENWQE_UID_OFFS(uid) | eevptr;

		while (1) {
			val = __genwqe_readq(cd, l_addr);

			if ((val == 0x0) || (val == -1ull))
				break;

			/* 38:24 */
			d_len  = (val & 0x0000007fff000000ull) >> 24;

			/* 39 */
			d_type = (val & 0x0000008000000000ull) >> 36;

			if (d_type) {	/* repeat */
				entries += d_len;
			} else {	/* size in bytes! */
				entries += d_len >> 3;
			}

			l_addr += 8;
		}
	}

	for (ring = 0; ring < 8; ring++) {
		addr = GENWQE_UID_OFFS(uid) | IO_EXTENDED_DIAG_MAP(ring);
		val = __genwqe_readq(cd, addr);

		if ((val == 0x0ull) || (val == -1ull))
			continue;

		traps = (val >> 24) & 0xff;
		traces = (val >> 16) & 0xff;
		trace_entries = val & 0xffff;

		entries += traps + (traces * trace_entries);
	}
	return entries;
}

/**
 * genwqe_ffdc_buff_read() - Implements LogoutExtendedErrorRegisters procedure
 */
int genwqe_ffdc_buff_read(struct genwqe_dev *cd, int uid,
			  struct genwqe_reg *regs, unsigned int max_regs)
{
	int i, traps, traces, trace, trace_entries, trace_entry, ring;
	unsigned int idx = 0;
	u32 eevptr_addr, l_addr, d_addr, d_len, d_type;
	u64 eevptr, e, val, addr;

	eevptr_addr = GENWQE_UID_OFFS(uid) | IO_EXTENDED_ERROR_POINTER;
	eevptr = __genwqe_readq(cd, eevptr_addr);

	if ((eevptr != 0x0) && (eevptr != 0xffffffffffffffffull)) {
		l_addr = GENWQE_UID_OFFS(uid) | eevptr;
		while (1) {
			e = __genwqe_readq(cd, l_addr);
			if ((e == 0x0) || (e == 0xffffffffffffffffull))
				break;

			d_addr = (e & 0x0000000000ffffffull);	    /* 23:0 */
			d_len  = (e & 0x0000007fff000000ull) >> 24; /* 38:24 */
			d_type = (e & 0x0000008000000000ull) >> 36; /* 39 */
			d_addr |= GENWQE_UID_OFFS(uid);

			if (d_type) {
				for (i = 0; i < (int)d_len; i++) {
					val = __genwqe_readq(cd, d_addr);
					set_reg_idx(cd, regs, &idx, max_regs,
						    d_addr, i, val);
				}
			} else {
				d_len >>= 3; /* Size in bytes! */
				for (i = 0; i < (int)d_len; i++, d_addr += 8) {
					val = __genwqe_readq(cd, d_addr);
					set_reg_idx(cd, regs, &idx, max_regs,
						    d_addr, 0, val);
				}
			}
			l_addr += 8;
		}
	}

	/*
	 * To save time, there are only 6 traces poplulated on Uid=2,
	 * Ring=1. each with iters=512.
	 */
	for (ring = 0; ring < 8; ring++) { /* 0 is fls, 1 is fds,
					      2...7 are ASI rings */
		addr = GENWQE_UID_OFFS(uid) | IO_EXTENDED_DIAG_MAP(ring);
		val = __genwqe_readq(cd, addr);

		if ((val == 0x0ull) || (val == -1ull))
			continue;

		traps = (val >> 24) & 0xff;	/* Number of Traps	*/
		traces = (val >> 16) & 0xff;	/* Number of Traces	*/
		trace_entries = val & 0xffff;	/* Entries per trace	*/

		/* Note: This is a combined loop that dumps both the traps */
		/* (for the trace == 0 case) as well as the traces 1 to    */
		/* 'traces'.						   */
		for (trace = 0; trace <= traces; trace++) {
			u32 diag_sel =
				GENWQE_EXTENDED_DIAG_SELECTOR(ring, trace);

			addr = (GENWQE_UID_OFFS(uid) |
				IO_EXTENDED_DIAG_SELECTOR);
			__genwqe_writeq(cd, addr, diag_sel);

			for (trace_entry = 0;
			     trace_entry < (trace ? trace_entries : traps);
			     trace_entry++) {
				addr = (GENWQE_UID_OFFS(uid) |
					IO_EXTENDED_DIAG_READ_MBX);
				val = __genwqe_readq(cd, addr);
				set_reg_idx(cd, regs, &idx, max_regs, addr,
					    (diag_sel<<16) | trace_entry, val);
			}
		}
	}
	return 0;
}

/**
 * genwqe_write_vreg() - Write register in virtual window
 *
 * Note, these registers are only accessible to the PF through the
 * VF-window. It is not intended for the VF to access.
 */
int genwqe_write_vreg(struct genwqe_dev *cd, u32 reg, u64 val, int func)
{
	__genwqe_writeq(cd, IO_PF_SLC_VIRTUAL_WINDOW, func & 0xf);
	__genwqe_writeq(cd, reg, val);
	return 0;
}

/**
 * genwqe_read_vreg() - Read register in virtual window
 *
 * Note, these registers are only accessible to the PF through the
 * VF-window. It is not intended for the VF to access.
 */
u64 genwqe_read_vreg(struct genwqe_dev *cd, u32 reg, int func)
{
	__genwqe_writeq(cd, IO_PF_SLC_VIRTUAL_WINDOW, func & 0xf);
	return __genwqe_readq(cd, reg);
}

/**
 * genwqe_base_clock_frequency() - Deteremine base clock frequency of the card
 *
 * Note: From a design perspective it turned out to be a bad idea to
 * use codes here to specifiy the frequency/speed values. An old
 * driver cannot understand new codes and is therefore always a
 * problem. Better is to measure out the value or put the
 * speed/frequency directly into a register which is always a valid
 * value for old as well as for new software.
 *
 * Return: Card clock in MHz
 */
int genwqe_base_clock_frequency(struct genwqe_dev *cd)
{
	u16 speed;		/*         MHz  MHz  MHz  MHz */
	static const int speed_grade[] = { 250, 200, 166, 175 };

	speed = (u16)((cd->slu_unitcfg >> 28) & 0x0full);
	if (speed >= ARRAY_SIZE(speed_grade))
		return 0;	/* illegal value */

	return speed_grade[speed];
}

/**
 * genwqe_stop_traps() - Stop traps
 *
 * Before reading out the analysis data, we need to stop the traps.
 */
void genwqe_stop_traps(struct genwqe_dev *cd)
{
	__genwqe_writeq(cd, IO_SLC_MISC_DEBUG_SET, 0xcull);
}

/**
 * genwqe_start_traps() - Start traps
 *
 * After having read the data, we can/must enable the traps again.
 */
void genwqe_start_traps(struct genwqe_dev *cd)
{
	__genwqe_writeq(cd, IO_SLC_MISC_DEBUG_CLR, 0xcull);

	if (genwqe_need_err_masking(cd))
		__genwqe_writeq(cd, IO_SLC_MISC_DEBUG, 0x0aull);
}