summaryrefslogtreecommitdiffstats
path: root/drivers/char/tpm/tpm_tis.c
blob: 65f7eecc45b01c489e2381b2311a95f2898527df (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
1148
1149
1150
1151
1152
1153
/*
 * Copyright (C) 2005, 2006 IBM Corporation
 * Copyright (C) 2014, 2015 Intel Corporation
 *
 * Authors:
 * Leendert van Doorn <leendert@watson.ibm.com>
 * Kylene Hall <kjhall@us.ibm.com>
 *
 * Maintained by: <tpmdd-devel@lists.sourceforge.net>
 *
 * Device driver for TCG/TCPA TPM (trusted platform module).
 * Specifications at www.trustedcomputinggroup.org
 *
 * This device driver implements the TPM interface as defined in
 * the TCG TPM Interface Spec version 1.2, revision 1.0.
 *
 * 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, version 2 of the
 * License.
 */
#include <linux/init.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/pnp.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/wait.h>
#include <linux/acpi.h>
#include <linux/freezer.h>
#include <acpi/actbl2.h>
#include "tpm.h"

enum tis_access {
	TPM_ACCESS_VALID = 0x80,
	TPM_ACCESS_ACTIVE_LOCALITY = 0x20,
	TPM_ACCESS_REQUEST_PENDING = 0x04,
	TPM_ACCESS_REQUEST_USE = 0x02,
};

enum tis_status {
	TPM_STS_VALID = 0x80,
	TPM_STS_COMMAND_READY = 0x40,
	TPM_STS_GO = 0x20,
	TPM_STS_DATA_AVAIL = 0x10,
	TPM_STS_DATA_EXPECT = 0x08,
};

enum tis_int_flags {
	TPM_GLOBAL_INT_ENABLE = 0x80000000,
	TPM_INTF_BURST_COUNT_STATIC = 0x100,
	TPM_INTF_CMD_READY_INT = 0x080,
	TPM_INTF_INT_EDGE_FALLING = 0x040,
	TPM_INTF_INT_EDGE_RISING = 0x020,
	TPM_INTF_INT_LEVEL_LOW = 0x010,
	TPM_INTF_INT_LEVEL_HIGH = 0x008,
	TPM_INTF_LOCALITY_CHANGE_INT = 0x004,
	TPM_INTF_STS_VALID_INT = 0x002,
	TPM_INTF_DATA_AVAIL_INT = 0x001,
};

enum tis_defaults {
	TIS_MEM_BASE = 0xFED40000,
	TIS_MEM_LEN = 0x5000,
	TIS_SHORT_TIMEOUT = 750,	/* ms */
	TIS_LONG_TIMEOUT = 2000,	/* 2 sec */
};

struct tpm_info {
	unsigned long start;
	unsigned long len;
	unsigned int irq;
};

static struct tpm_info tis_default_info = {
	.start = TIS_MEM_BASE,
	.len = TIS_MEM_LEN,
	.irq = 0,
};

/* Some timeout values are needed before it is known whether the chip is
 * TPM 1.0 or TPM 2.0.
 */
#define TIS_TIMEOUT_A_MAX	max(TIS_SHORT_TIMEOUT, TPM2_TIMEOUT_A)
#define TIS_TIMEOUT_B_MAX	max(TIS_LONG_TIMEOUT, TPM2_TIMEOUT_B)
#define TIS_TIMEOUT_C_MAX	max(TIS_SHORT_TIMEOUT, TPM2_TIMEOUT_C)
#define TIS_TIMEOUT_D_MAX	max(TIS_SHORT_TIMEOUT, TPM2_TIMEOUT_D)

#define	TPM_ACCESS(l)			(0x0000 | ((l) << 12))
#define	TPM_INT_ENABLE(l)		(0x0008 | ((l) << 12))
#define	TPM_INT_VECTOR(l)		(0x000C | ((l) << 12))
#define	TPM_INT_STATUS(l)		(0x0010 | ((l) << 12))
#define	TPM_INTF_CAPS(l)		(0x0014 | ((l) << 12))
#define	TPM_STS(l)			(0x0018 | ((l) << 12))
#define	TPM_STS3(l)			(0x001b | ((l) << 12))
#define	TPM_DATA_FIFO(l)		(0x0024 | ((l) << 12))

#define	TPM_DID_VID(l)			(0x0F00 | ((l) << 12))
#define	TPM_RID(l)			(0x0F04 | ((l) << 12))

struct priv_data {
	bool irq_tested;
};

#if defined(CONFIG_PNP) && defined(CONFIG_ACPI)
static int has_hid(struct acpi_device *dev, const char *hid)
{
	struct acpi_hardware_id *id;

	list_for_each_entry(id, &dev->pnp.ids, list)
		if (!strcmp(hid, id->id))
			return 1;

	return 0;
}

static inline int is_itpm(struct acpi_device *dev)
{
	return has_hid(dev, "INTC0102");
}

static inline int is_fifo(struct acpi_device *dev)
{
	struct acpi_table_tpm2 *tbl;
	acpi_status st;

	/* TPM 1.2 FIFO */
	if (!has_hid(dev, "MSFT0101"))
		return 1;

	st = acpi_get_table(ACPI_SIG_TPM2, 1,
			    (struct acpi_table_header **) &tbl);
	if (ACPI_FAILURE(st)) {
		dev_err(&dev->dev, "failed to get TPM2 ACPI table\n");
		return 0;
	}

	if (le32_to_cpu(tbl->start_method) != TPM2_START_FIFO)
		return 0;

	/* TPM 2.0 FIFO */
	return 1;
}
#else
static inline int is_itpm(struct acpi_device *dev)
{
	return 0;
}

static inline int is_fifo(struct acpi_device *dev)
{
	return 1;
}
#endif

/* Before we attempt to access the TPM we must see that the valid bit is set.
 * The specification says that this bit is 0 at reset and remains 0 until the
 * 'TPM has gone through its self test and initialization and has established
 * correct values in the other bits.' */
static int wait_startup(struct tpm_chip *chip, int l)
{
	unsigned long stop = jiffies + chip->vendor.timeout_a;
	do {
		if (ioread8(chip->vendor.iobase + TPM_ACCESS(l)) &
		    TPM_ACCESS_VALID)
			return 0;
		msleep(TPM_TIMEOUT);
	} while (time_before(jiffies, stop));
	return -1;
}

static int check_locality(struct tpm_chip *chip, int l)
{
	if ((ioread8(chip->vendor.iobase + TPM_ACCESS(l)) &
	     (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) ==
	    (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID))
		return chip->vendor.locality = l;

	return -1;
}

static void release_locality(struct tpm_chip *chip, int l, int force)
{
	if (force || (ioread8(chip->vendor.iobase + TPM_ACCESS(l)) &
		      (TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID)) ==
	    (TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID))
		iowrite8(TPM_ACCESS_ACTIVE_LOCALITY,
			 chip->vendor.iobase + TPM_ACCESS(l));
}

static int request_locality(struct tpm_chip *chip, int l)
{
	unsigned long stop, timeout;
	long rc;

	if (check_locality(chip, l) >= 0)
		return l;

	iowrite8(TPM_ACCESS_REQUEST_USE,
		 chip->vendor.iobase + TPM_ACCESS(l));

	stop = jiffies + chip->vendor.timeout_a;

	if (chip->vendor.irq) {
again:
		timeout = stop - jiffies;
		if ((long)timeout <= 0)
			return -1;
		rc = wait_event_interruptible_timeout(chip->vendor.int_queue,
						      (check_locality
						       (chip, l) >= 0),
						      timeout);
		if (rc > 0)
			return l;
		if (rc == -ERESTARTSYS && freezing(current)) {
			clear_thread_flag(TIF_SIGPENDING);
			goto again;
		}
	} else {
		/* wait for burstcount */
		do {
			if (check_locality(chip, l) >= 0)
				return l;
			msleep(TPM_TIMEOUT);
		}
		while (time_before(jiffies, stop));
	}
	return -1;
}

static u8 tpm_tis_status(struct tpm_chip *chip)
{
	return ioread8(chip->vendor.iobase +
		       TPM_STS(chip->vendor.locality));
}

static void tpm_tis_ready(struct tpm_chip *chip)
{
	/* this causes the current command to be aborted */
	iowrite8(TPM_STS_COMMAND_READY,
		 chip->vendor.iobase + TPM_STS(chip->vendor.locality));
}

static int get_burstcount(struct tpm_chip *chip)
{
	unsigned long stop;
	int burstcnt;

	/* wait for burstcount */
	/* which timeout value, spec has 2 answers (c & d) */
	stop = jiffies + chip->vendor.timeout_d;
	do {
		burstcnt = ioread8(chip->vendor.iobase +
				   TPM_STS(chip->vendor.locality) + 1);
		burstcnt += ioread8(chip->vendor.iobase +
				    TPM_STS(chip->vendor.locality) +
				    2) << 8;
		if (burstcnt)
			return burstcnt;
		msleep(TPM_TIMEOUT);
	} while (time_before(jiffies, stop));
	return -EBUSY;
}

static int recv_data(struct tpm_chip *chip, u8 *buf, size_t count)
{
	int size = 0, burstcnt;
	while (size < count &&
	       wait_for_tpm_stat(chip,
				 TPM_STS_DATA_AVAIL | TPM_STS_VALID,
				 chip->vendor.timeout_c,
				 &chip->vendor.read_queue, true)
	       == 0) {
		burstcnt = get_burstcount(chip);
		for (; burstcnt > 0 && size < count; burstcnt--)
			buf[size++] = ioread8(chip->vendor.iobase +
					      TPM_DATA_FIFO(chip->vendor.
							    locality));
	}
	return size;
}

static int tpm_tis_recv(struct tpm_chip *chip, u8 *buf, size_t count)
{
	int size = 0;
	int expected, status;

	if (count < TPM_HEADER_SIZE) {
		size = -EIO;
		goto out;
	}

	/* read first 10 bytes, including tag, paramsize, and result */
	if ((size =
	     recv_data(chip, buf, TPM_HEADER_SIZE)) < TPM_HEADER_SIZE) {
		dev_err(chip->pdev, "Unable to read header\n");
		goto out;
	}

	expected = be32_to_cpu(*(__be32 *) (buf + 2));
	if (expected > count) {
		size = -EIO;
		goto out;
	}

	if ((size +=
	     recv_data(chip, &buf[TPM_HEADER_SIZE],
		       expected - TPM_HEADER_SIZE)) < expected) {
		dev_err(chip->pdev, "Unable to read remainder of result\n");
		size = -ETIME;
		goto out;
	}

	wait_for_tpm_stat(chip, TPM_STS_VALID, chip->vendor.timeout_c,
			  &chip->vendor.int_queue, false);
	status = tpm_tis_status(chip);
	if (status & TPM_STS_DATA_AVAIL) {	/* retry? */
		dev_err(chip->pdev, "Error left over data\n");
		size = -EIO;
		goto out;
	}

out:
	tpm_tis_ready(chip);
	release_locality(chip, chip->vendor.locality, 0);
	return size;
}

static bool itpm;
module_param(itpm, bool, 0444);
MODULE_PARM_DESC(itpm, "Force iTPM workarounds (found on some Lenovo laptops)");

/*
 * If interrupts are used (signaled by an irq set in the vendor structure)
 * tpm.c can skip polling for the data to be available as the interrupt is
 * waited for here
 */
static int tpm_tis_send_data(struct tpm_chip *chip, u8 *buf, size_t len)
{
	int rc, status, burstcnt;
	size_t count = 0;

	if (request_locality(chip, 0) < 0)
		return -EBUSY;

	status = tpm_tis_status(chip);
	if ((status & TPM_STS_COMMAND_READY) == 0) {
		tpm_tis_ready(chip);
		if (wait_for_tpm_stat
		    (chip, TPM_STS_COMMAND_READY, chip->vendor.timeout_b,
		     &chip->vendor.int_queue, false) < 0) {
			rc = -ETIME;
			goto out_err;
		}
	}

	while (count < len - 1) {
		burstcnt = get_burstcount(chip);
		for (; burstcnt > 0 && count < len - 1; burstcnt--) {
			iowrite8(buf[count], chip->vendor.iobase +
				 TPM_DATA_FIFO(chip->vendor.locality));
			count++;
		}

		wait_for_tpm_stat(chip, TPM_STS_VALID, chip->vendor.timeout_c,
				  &chip->vendor.int_queue, false);
		status = tpm_tis_status(chip);
		if (!itpm && (status & TPM_STS_DATA_EXPECT) == 0) {
			rc = -EIO;
			goto out_err;
		}
	}

	/* write last byte */
	iowrite8(buf[count],
		 chip->vendor.iobase + TPM_DATA_FIFO(chip->vendor.locality));
	wait_for_tpm_stat(chip, TPM_STS_VALID, chip->vendor.timeout_c,
			  &chip->vendor.int_queue, false);
	status = tpm_tis_status(chip);
	if ((status & TPM_STS_DATA_EXPECT) != 0) {
		rc = -EIO;
		goto out_err;
	}

	return 0;

out_err:
	tpm_tis_ready(chip);
	release_locality(chip, chip->vendor.locality, 0);
	return rc;
}

static void disable_interrupts(struct tpm_chip *chip)
{
	u32 intmask;

	intmask =
	    ioread32(chip->vendor.iobase +
		     TPM_INT_ENABLE(chip->vendor.locality));
	intmask &= ~TPM_GLOBAL_INT_ENABLE;
	iowrite32(intmask,
		  chip->vendor.iobase +
		  TPM_INT_ENABLE(chip->vendor.locality));
	free_irq(chip->vendor.irq, chip);
	chip->vendor.irq = 0;
}

/*
 * If interrupts are used (signaled by an irq set in the vendor structure)
 * tpm.c can skip polling for the data to be available as the interrupt is
 * waited for here
 */
static int tpm_tis_send_main(struct tpm_chip *chip, u8 *buf, size_t len)
{
	int rc;
	u32 ordinal;
	unsigned long dur;

	rc = tpm_tis_send_data(chip, buf, len);
	if (rc < 0)
		return rc;

	/* go and do it */
	iowrite8(TPM_STS_GO,
		 chip->vendor.iobase + TPM_STS(chip->vendor.locality));

	if (chip->vendor.irq) {
		ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));

		if (chip->flags & TPM_CHIP_FLAG_TPM2)
			dur = tpm2_calc_ordinal_duration(chip, ordinal);
		else
			dur = tpm_calc_ordinal_duration(chip, ordinal);

		if (wait_for_tpm_stat
		    (chip, TPM_STS_DATA_AVAIL | TPM_STS_VALID, dur,
		     &chip->vendor.read_queue, false) < 0) {
			rc = -ETIME;
			goto out_err;
		}
	}
	return len;
out_err:
	tpm_tis_ready(chip);
	release_locality(chip, chip->vendor.locality, 0);
	return rc;
}

static int tpm_tis_send(struct tpm_chip *chip, u8 *buf, size_t len)
{
	int rc, irq;
	struct priv_data *priv = chip->vendor.priv;

	if (!chip->vendor.irq || priv->irq_tested)
		return tpm_tis_send_main(chip, buf, len);

	/* Verify receipt of the expected IRQ */
	irq = chip->vendor.irq;
	chip->vendor.irq = 0;
	rc = tpm_tis_send_main(chip, buf, len);
	chip->vendor.irq = irq;
	if (!priv->irq_tested)
		msleep(1);
	if (!priv->irq_tested) {
		disable_interrupts(chip);
		dev_err(chip->pdev,
			FW_BUG "TPM interrupt not working, polling instead\n");
	}
	priv->irq_tested = true;
	return rc;
}

struct tis_vendor_timeout_override {
	u32 did_vid;
	unsigned long timeout_us[4];
};

static const struct tis_vendor_timeout_override vendor_timeout_overrides[] = {
	/* Atmel 3204 */
	{ 0x32041114, { (TIS_SHORT_TIMEOUT*1000), (TIS_LONG_TIMEOUT*1000),
			(TIS_SHORT_TIMEOUT*1000), (TIS_SHORT_TIMEOUT*1000) } },
};

static bool tpm_tis_update_timeouts(struct tpm_chip *chip,
				    unsigned long *timeout_cap)
{
	int i;
	u32 did_vid;

	did_vid = ioread32(chip->vendor.iobase + TPM_DID_VID(0));

	for (i = 0; i != ARRAY_SIZE(vendor_timeout_overrides); i++) {
		if (vendor_timeout_overrides[i].did_vid != did_vid)
			continue;
		memcpy(timeout_cap, vendor_timeout_overrides[i].timeout_us,
		       sizeof(vendor_timeout_overrides[i].timeout_us));
		return true;
	}

	return false;
}

/*
 * Early probing for iTPM with STS_DATA_EXPECT flaw.
 * Try sending command without itpm flag set and if that
 * fails, repeat with itpm flag set.
 */
static int probe_itpm(struct tpm_chip *chip)
{
	int rc = 0;
	u8 cmd_getticks[] = {
		0x00, 0xc1, 0x00, 0x00, 0x00, 0x0a,
		0x00, 0x00, 0x00, 0xf1
	};
	size_t len = sizeof(cmd_getticks);
	bool rem_itpm = itpm;
	u16 vendor = ioread16(chip->vendor.iobase + TPM_DID_VID(0));

	/* probe only iTPMS */
	if (vendor != TPM_VID_INTEL)
		return 0;

	itpm = false;

	rc = tpm_tis_send_data(chip, cmd_getticks, len);
	if (rc == 0)
		goto out;

	tpm_tis_ready(chip);
	release_locality(chip, chip->vendor.locality, 0);

	itpm = true;

	rc = tpm_tis_send_data(chip, cmd_getticks, len);
	if (rc == 0) {
		dev_info(chip->pdev, "Detected an iTPM.\n");
		rc = 1;
	} else
		rc = -EFAULT;

out:
	itpm = rem_itpm;
	tpm_tis_ready(chip);
	release_locality(chip, chip->vendor.locality, 0);

	return rc;
}

static bool tpm_tis_req_canceled(struct tpm_chip *chip, u8 status)
{
	switch (chip->vendor.manufacturer_id) {
	case TPM_VID_WINBOND:
		return ((status == TPM_STS_VALID) ||
			(status == (TPM_STS_VALID | TPM_STS_COMMAND_READY)));
	case TPM_VID_STM:
		return (status == (TPM_STS_VALID | TPM_STS_COMMAND_READY));
	default:
		return (status == TPM_STS_COMMAND_READY);
	}
}

static const struct tpm_class_ops tpm_tis = {
	.status = tpm_tis_status,
	.recv = tpm_tis_recv,
	.send = tpm_tis_send,
	.cancel = tpm_tis_ready,
	.update_timeouts = tpm_tis_update_timeouts,
	.req_complete_mask = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
	.req_complete_val = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
	.req_canceled = tpm_tis_req_canceled,
};

static irqreturn_t tis_int_probe(int irq, void *dev_id)
{
	struct tpm_chip *chip = dev_id;
	u32 interrupt;

	interrupt = ioread32(chip->vendor.iobase +
			     TPM_INT_STATUS(chip->vendor.locality));

	if (interrupt == 0)
		return IRQ_NONE;

	chip->vendor.probed_irq = irq;

	/* Clear interrupts handled with TPM_EOI */
	iowrite32(interrupt,
		  chip->vendor.iobase +
		  TPM_INT_STATUS(chip->vendor.locality));
	return IRQ_HANDLED;
}

static irqreturn_t tis_int_handler(int dummy, void *dev_id)
{
	struct tpm_chip *chip = dev_id;
	u32 interrupt;
	int i;

	interrupt = ioread32(chip->vendor.iobase +
			     TPM_INT_STATUS(chip->vendor.locality));

	if (interrupt == 0)
		return IRQ_NONE;

	((struct priv_data *)chip->vendor.priv)->irq_tested = true;
	if (interrupt & TPM_INTF_DATA_AVAIL_INT)
		wake_up_interruptible(&chip->vendor.read_queue);
	if (interrupt & TPM_INTF_LOCALITY_CHANGE_INT)
		for (i = 0; i < 5; i++)
			if (check_locality(chip, i) >= 0)
				break;
	if (interrupt &
	    (TPM_INTF_LOCALITY_CHANGE_INT | TPM_INTF_STS_VALID_INT |
	     TPM_INTF_CMD_READY_INT))
		wake_up_interruptible(&chip->vendor.int_queue);

	/* Clear interrupts handled with TPM_EOI */
	iowrite32(interrupt,
		  chip->vendor.iobase +
		  TPM_INT_STATUS(chip->vendor.locality));
	ioread32(chip->vendor.iobase + TPM_INT_STATUS(chip->vendor.locality));
	return IRQ_HANDLED;
}

static bool interrupts = true;
module_param(interrupts, bool, 0444);
MODULE_PARM_DESC(interrupts, "Enable interrupts");

static void tpm_tis_remove(struct tpm_chip *chip)
{
	if (chip->flags & TPM_CHIP_FLAG_TPM2)
		tpm2_shutdown(chip, TPM2_SU_CLEAR);

	iowrite32(~TPM_GLOBAL_INT_ENABLE &
		  ioread32(chip->vendor.iobase +
			   TPM_INT_ENABLE(chip->vendor.
					  locality)),
		  chip->vendor.iobase +
		  TPM_INT_ENABLE(chip->vendor.locality));
	release_locality(chip, chip->vendor.locality, 1);
}

static int tpm_tis_init(struct device *dev, struct tpm_info *tpm_info,
			acpi_handle acpi_dev_handle)
{
	u32 vendor, intfcaps, intmask;
	int rc, i, irq_s, irq_e, probe;
	int irq_r = -1;
	struct tpm_chip *chip;
	struct priv_data *priv;

	priv = devm_kzalloc(dev, sizeof(struct priv_data), GFP_KERNEL);
	if (priv == NULL)
		return -ENOMEM;

	chip = tpmm_chip_alloc(dev, &tpm_tis);
	if (IS_ERR(chip))
		return PTR_ERR(chip);

	chip->vendor.priv = priv;
#ifdef CONFIG_ACPI
	chip->acpi_dev_handle = acpi_dev_handle;
#endif

	chip->vendor.iobase = devm_ioremap(dev, tpm_info->start, tpm_info->len);
	if (!chip->vendor.iobase)
		return -EIO;

	/* Maximum timeouts */
	chip->vendor.timeout_a = TIS_TIMEOUT_A_MAX;
	chip->vendor.timeout_b = TIS_TIMEOUT_B_MAX;
	chip->vendor.timeout_c = TIS_TIMEOUT_C_MAX;
	chip->vendor.timeout_d = TIS_TIMEOUT_D_MAX;

	if (wait_startup(chip, 0) != 0) {
		rc = -ENODEV;
		goto out_err;
	}

	if (request_locality(chip, 0) != 0) {
		rc = -ENODEV;
		goto out_err;
	}

	rc = tpm2_probe(chip);
	if (rc)
		goto out_err;

	vendor = ioread32(chip->vendor.iobase + TPM_DID_VID(0));
	chip->vendor.manufacturer_id = vendor;

	dev_info(dev, "%s TPM (device-id 0x%X, rev-id %d)\n",
		 (chip->flags & TPM_CHIP_FLAG_TPM2) ? "2.0" : "1.2",
		 vendor >> 16, ioread8(chip->vendor.iobase + TPM_RID(0)));

	if (!itpm) {
		probe = probe_itpm(chip);
		if (probe < 0) {
			rc = -ENODEV;
			goto out_err;
		}
		itpm = !!probe;
	}

	if (itpm)
		dev_info(dev, "Intel iTPM workaround enabled\n");


	/* Figure out the capabilities */
	intfcaps =
	    ioread32(chip->vendor.iobase +
		     TPM_INTF_CAPS(chip->vendor.locality));
	dev_dbg(dev, "TPM interface capabilities (0x%x):\n",
		intfcaps);
	if (intfcaps & TPM_INTF_BURST_COUNT_STATIC)
		dev_dbg(dev, "\tBurst Count Static\n");
	if (intfcaps & TPM_INTF_CMD_READY_INT)
		dev_dbg(dev, "\tCommand Ready Int Support\n");
	if (intfcaps & TPM_INTF_INT_EDGE_FALLING)
		dev_dbg(dev, "\tInterrupt Edge Falling\n");
	if (intfcaps & TPM_INTF_INT_EDGE_RISING)
		dev_dbg(dev, "\tInterrupt Edge Rising\n");
	if (intfcaps & TPM_INTF_INT_LEVEL_LOW)
		dev_dbg(dev, "\tInterrupt Level Low\n");
	if (intfcaps & TPM_INTF_INT_LEVEL_HIGH)
		dev_dbg(dev, "\tInterrupt Level High\n");
	if (intfcaps & TPM_INTF_LOCALITY_CHANGE_INT)
		dev_dbg(dev, "\tLocality Change Int Support\n");
	if (intfcaps & TPM_INTF_STS_VALID_INT)
		dev_dbg(dev, "\tSts Valid Int Support\n");
	if (intfcaps & TPM_INTF_DATA_AVAIL_INT)
		dev_dbg(dev, "\tData Avail Int Support\n");

	/* INTERRUPT Setup */
	init_waitqueue_head(&chip->vendor.read_queue);
	init_waitqueue_head(&chip->vendor.int_queue);

	intmask =
	    ioread32(chip->vendor.iobase +
		     TPM_INT_ENABLE(chip->vendor.locality));

	intmask |= TPM_INTF_CMD_READY_INT
	    | TPM_INTF_LOCALITY_CHANGE_INT | TPM_INTF_DATA_AVAIL_INT
	    | TPM_INTF_STS_VALID_INT;

	iowrite32(intmask,
		  chip->vendor.iobase +
		  TPM_INT_ENABLE(chip->vendor.locality));
	if (interrupts)
		chip->vendor.irq = tpm_info->irq;
	if (interrupts && !chip->vendor.irq) {
		irq_s =
		    ioread8(chip->vendor.iobase +
			    TPM_INT_VECTOR(chip->vendor.locality));
		irq_r = irq_s;
		if (irq_s) {
			irq_e = irq_s;
		} else {
			irq_s = 3;
			irq_e = 15;
		}

		for (i = irq_s; i <= irq_e && chip->vendor.irq == 0; i++) {
			iowrite8(i, chip->vendor.iobase +
				 TPM_INT_VECTOR(chip->vendor.locality));
			if (devm_request_irq
			    (dev, i, tis_int_probe, IRQF_SHARED,
			     chip->devname, chip) != 0) {
				dev_info(chip->pdev,
					 "Unable to request irq: %d for probe\n",
					 i);
				continue;
			}

			/* Clear all existing */
			iowrite32(ioread32
				  (chip->vendor.iobase +
				   TPM_INT_STATUS(chip->vendor.locality)),
				  chip->vendor.iobase +
				  TPM_INT_STATUS(chip->vendor.locality));

			/* Turn on */
			iowrite32(intmask | TPM_GLOBAL_INT_ENABLE,
				  chip->vendor.iobase +
				  TPM_INT_ENABLE(chip->vendor.locality));

			chip->vendor.probed_irq = 0;

			/* Generate Interrupts */
			if (chip->flags & TPM_CHIP_FLAG_TPM2)
				tpm2_gen_interrupt(chip);
			else
				tpm_gen_interrupt(chip);

			chip->vendor.irq = chip->vendor.probed_irq;

			/* free_irq will call into tis_int_probe;
			   clear all irqs we haven't seen while doing
			   tpm_gen_interrupt */
			iowrite32(ioread32
				  (chip->vendor.iobase +
				   TPM_INT_STATUS(chip->vendor.locality)),
				  chip->vendor.iobase +
				  TPM_INT_STATUS(chip->vendor.locality));

			/* Turn off */
			iowrite32(intmask,
				  chip->vendor.iobase +
				  TPM_INT_ENABLE(chip->vendor.locality));

			devm_free_irq(dev, i, chip);
		}
	}
	if (chip->vendor.irq) {
		iowrite8(chip->vendor.irq,
			 chip->vendor.iobase +
			 TPM_INT_VECTOR(chip->vendor.locality));
		if (devm_request_irq
		    (dev, chip->vendor.irq, tis_int_handler, IRQF_SHARED,
		     chip->devname, chip) != 0) {
			dev_info(chip->pdev,
				 "Unable to request irq: %d for use\n",
				 chip->vendor.irq);
			chip->vendor.irq = 0;
		} else {
			/* Clear all existing */
			iowrite32(ioread32
				  (chip->vendor.iobase +
				   TPM_INT_STATUS(chip->vendor.locality)),
				  chip->vendor.iobase +
				  TPM_INT_STATUS(chip->vendor.locality));

			/* Turn on */
			iowrite32(intmask | TPM_GLOBAL_INT_ENABLE,
				  chip->vendor.iobase +
				  TPM_INT_ENABLE(chip->vendor.locality));
		}
	} else if (irq_r != -1)
		iowrite8(irq_r, chip->vendor.iobase +
			 TPM_INT_VECTOR(chip->vendor.locality));

	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
		chip->vendor.timeout_a = msecs_to_jiffies(TPM2_TIMEOUT_A);
		chip->vendor.timeout_b = msecs_to_jiffies(TPM2_TIMEOUT_B);
		chip->vendor.timeout_c = msecs_to_jiffies(TPM2_TIMEOUT_C);
		chip->vendor.timeout_d = msecs_to_jiffies(TPM2_TIMEOUT_D);
		chip->vendor.duration[TPM_SHORT] =
			msecs_to_jiffies(TPM2_DURATION_SHORT);
		chip->vendor.duration[TPM_MEDIUM] =
			msecs_to_jiffies(TPM2_DURATION_MEDIUM);
		chip->vendor.duration[TPM_LONG] =
			msecs_to_jiffies(TPM2_DURATION_LONG);

		rc = tpm2_do_selftest(chip);
		if (rc == TPM2_RC_INITIALIZE) {
			dev_warn(dev, "Firmware has not started TPM\n");
			rc  = tpm2_startup(chip, TPM2_SU_CLEAR);
			if (!rc)
				rc = tpm2_do_selftest(chip);
		}

		if (rc) {
			dev_err(dev, "TPM self test failed\n");
			if (rc > 0)
				rc = -ENODEV;
			goto out_err;
		}
	} else {
		if (tpm_get_timeouts(chip)) {
			dev_err(dev, "Could not get TPM timeouts and durations\n");
			rc = -ENODEV;
			goto out_err;
		}

		if (tpm_do_selftest(chip)) {
			dev_err(dev, "TPM self test failed\n");
			rc = -ENODEV;
			goto out_err;
		}
	}

	return tpm_chip_register(chip);
out_err:
	tpm_tis_remove(chip);
	return rc;
}

#ifdef CONFIG_PM_SLEEP
static void tpm_tis_reenable_interrupts(struct tpm_chip *chip)
{
	u32 intmask;

	/* reenable interrupts that device may have lost or
	   BIOS/firmware may have disabled */
	iowrite8(chip->vendor.irq, chip->vendor.iobase +
		 TPM_INT_VECTOR(chip->vendor.locality));

	intmask =
	    ioread32(chip->vendor.iobase +
		     TPM_INT_ENABLE(chip->vendor.locality));

	intmask |= TPM_INTF_CMD_READY_INT
	    | TPM_INTF_LOCALITY_CHANGE_INT | TPM_INTF_DATA_AVAIL_INT
	    | TPM_INTF_STS_VALID_INT | TPM_GLOBAL_INT_ENABLE;

	iowrite32(intmask,
		  chip->vendor.iobase + TPM_INT_ENABLE(chip->vendor.locality));
}

static int tpm_tis_resume(struct device *dev)
{
	struct tpm_chip *chip = dev_get_drvdata(dev);
	int ret;

	if (chip->vendor.irq)
		tpm_tis_reenable_interrupts(chip);

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

	/* TPM 1.2 requires self-test on resume. This function actually returns
	 * an error code but for unknown reason it isn't handled.
	 */
	if (!(chip->flags & TPM_CHIP_FLAG_TPM2))
		tpm_do_selftest(chip);

	return 0;
}
#endif

static SIMPLE_DEV_PM_OPS(tpm_tis_pm, tpm_pm_suspend, tpm_tis_resume);

#ifdef CONFIG_PNP
static int tpm_tis_pnp_init(struct pnp_dev *pnp_dev,
				      const struct pnp_device_id *pnp_id)
{
	struct tpm_info tpm_info = tis_default_info;
	acpi_handle acpi_dev_handle = NULL;

	tpm_info.start = pnp_mem_start(pnp_dev, 0);
	tpm_info.len = pnp_mem_len(pnp_dev, 0);

	if (pnp_irq_valid(pnp_dev, 0))
		tpm_info.irq = pnp_irq(pnp_dev, 0);
	else
		interrupts = false;

#ifdef CONFIG_ACPI
	if (pnp_acpi_device(pnp_dev)) {
		if (is_itpm(pnp_acpi_device(pnp_dev)))
			itpm = true;

		acpi_dev_handle = pnp_acpi_device(pnp_dev)->handle;
	}
#endif

	return tpm_tis_init(&pnp_dev->dev, &tpm_info, acpi_dev_handle);
}

static struct pnp_device_id tpm_pnp_tbl[] = {
	{"PNP0C31", 0},		/* TPM */
	{"ATM1200", 0},		/* Atmel */
	{"IFX0102", 0},		/* Infineon */
	{"BCM0101", 0},		/* Broadcom */
	{"BCM0102", 0},		/* Broadcom */
	{"NSC1200", 0},		/* National */
	{"ICO0102", 0},		/* Intel */
	/* Add new here */
	{"", 0},		/* User Specified */
	{"", 0}			/* Terminator */
};
MODULE_DEVICE_TABLE(pnp, tpm_pnp_tbl);

static void tpm_tis_pnp_remove(struct pnp_dev *dev)
{
	struct tpm_chip *chip = pnp_get_drvdata(dev);

	tpm_chip_unregister(chip);
	tpm_tis_remove(chip);
}

static struct pnp_driver tis_pnp_driver = {
	.name = "tpm_tis",
	.id_table = tpm_pnp_tbl,
	.probe = tpm_tis_pnp_init,
	.remove = tpm_tis_pnp_remove,
	.driver	= {
		.pm = &tpm_tis_pm,
	},
};

#define TIS_HID_USR_IDX sizeof(tpm_pnp_tbl)/sizeof(struct pnp_device_id) -2
module_param_string(hid, tpm_pnp_tbl[TIS_HID_USR_IDX].id,
		    sizeof(tpm_pnp_tbl[TIS_HID_USR_IDX].id), 0444);
MODULE_PARM_DESC(hid, "Set additional specific HID for this driver to probe");
#endif

#ifdef CONFIG_ACPI
static int tpm_check_resource(struct acpi_resource *ares, void *data)
{
	struct tpm_info *tpm_info = (struct tpm_info *) data;
	struct resource res;

	if (acpi_dev_resource_interrupt(ares, 0, &res)) {
		tpm_info->irq = res.start;
	} else if (acpi_dev_resource_memory(ares, &res)) {
		tpm_info->start = res.start;
		tpm_info->len = resource_size(&res);
	}

	return 1;
}

static int tpm_tis_acpi_init(struct acpi_device *acpi_dev)
{
	struct list_head resources;
	struct tpm_info tpm_info = tis_default_info;
	int ret;

	if (!is_fifo(acpi_dev))
		return -ENODEV;

	INIT_LIST_HEAD(&resources);
	ret = acpi_dev_get_resources(acpi_dev, &resources, tpm_check_resource,
				     &tpm_info);
	if (ret < 0)
		return ret;

	acpi_dev_free_resource_list(&resources);

	if (!tpm_info.irq)
		interrupts = false;

	if (is_itpm(acpi_dev))
		itpm = true;

	return tpm_tis_init(&acpi_dev->dev, &tpm_info, acpi_dev->handle);
}

static int tpm_tis_acpi_remove(struct acpi_device *dev)
{
	struct tpm_chip *chip = dev_get_drvdata(&dev->dev);

	tpm_chip_unregister(chip);
	tpm_tis_remove(chip);

	return 0;
}

static struct acpi_device_id tpm_acpi_tbl[] = {
	{"MSFT0101", 0},	/* TPM 2.0 */
	/* Add new here */
	{"", 0},		/* User Specified */
	{"", 0}			/* Terminator */
};
MODULE_DEVICE_TABLE(acpi, tpm_acpi_tbl);

static struct acpi_driver tis_acpi_driver = {
	.name = "tpm_tis",
	.ids = tpm_acpi_tbl,
	.ops = {
		.add = tpm_tis_acpi_init,
		.remove = tpm_tis_acpi_remove,
	},
	.drv = {
		.pm = &tpm_tis_pm,
	},
};
#endif

static struct platform_driver tis_drv = {
	.driver = {
		.name		= "tpm_tis",
		.pm		= &tpm_tis_pm,
	},
};

static struct platform_device *pdev;

static bool force;
module_param(force, bool, 0444);
MODULE_PARM_DESC(force, "Force device probe rather than using ACPI entry");
static int __init init_tis(void)
{
	int rc;
#ifdef CONFIG_PNP
	if (!force) {
		rc = pnp_register_driver(&tis_pnp_driver);
		if (rc)
			return rc;
	}
#endif
#ifdef CONFIG_ACPI
	if (!force) {
		rc = acpi_bus_register_driver(&tis_acpi_driver);
		if (rc) {
#ifdef CONFIG_PNP
			pnp_unregister_driver(&tis_pnp_driver);
#endif
			return rc;
		}
	}
#endif
	if (!force)
		return 0;

	rc = platform_driver_register(&tis_drv);
	if (rc < 0)
		return rc;
	pdev = platform_device_register_simple("tpm_tis", -1, NULL, 0);
	if (IS_ERR(pdev)) {
		rc = PTR_ERR(pdev);
		goto err_dev;
	}
	rc = tpm_tis_init(&pdev->dev, &tis_default_info, NULL);
	if (rc)
		goto err_init;
	return 0;
err_init:
	platform_device_unregister(pdev);
err_dev:
	platform_driver_unregister(&tis_drv);
	return rc;
}

static void __exit cleanup_tis(void)
{
	struct tpm_chip *chip;
#if defined(CONFIG_PNP) || defined(CONFIG_ACPI)
	if (!force) {
#ifdef CONFIG_ACPI
		acpi_bus_unregister_driver(&tis_acpi_driver);
#endif
#ifdef CONFIG_PNP
		pnp_unregister_driver(&tis_pnp_driver);
#endif
		return;
	}
#endif
	chip = dev_get_drvdata(&pdev->dev);
	tpm_chip_unregister(chip);
	tpm_tis_remove(chip);
	platform_device_unregister(pdev);
	platform_driver_unregister(&tis_drv);
}

module_init(init_tis);
module_exit(cleanup_tis);
MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
MODULE_DESCRIPTION("TPM Driver");
MODULE_VERSION("2.0");
MODULE_LICENSE("GPL");