xref: /linux/drivers/char/tpm/tpm1-cmd.c (revision 96ac6d435100450f0565708d9b885ea2a7400e0a)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (C) 2004 IBM Corporation
4  * Copyright (C) 2014 Intel Corporation
5  *
6  * Authors:
7  * Leendert van Doorn <leendert@watson.ibm.com>
8  * Dave Safford <safford@watson.ibm.com>
9  * Reiner Sailer <sailer@watson.ibm.com>
10  * Kylene Hall <kjhall@us.ibm.com>
11  *
12  * Device driver for TCG/TCPA TPM (trusted platform module).
13  * Specifications at www.trustedcomputinggroup.org
14  */
15 
16 #include <linux/poll.h>
17 #include <linux/slab.h>
18 #include <linux/mutex.h>
19 #include <linux/spinlock.h>
20 #include <linux/freezer.h>
21 #include <linux/tpm_eventlog.h>
22 
23 #include "tpm.h"
24 
25 #define TPM_MAX_ORDINAL 243
26 
27 /*
28  * Array with one entry per ordinal defining the maximum amount
29  * of time the chip could take to return the result.  The ordinal
30  * designation of short, medium or long is defined in a table in
31  * TCG Specification TPM Main Part 2 TPM Structures Section 17. The
32  * values of the SHORT, MEDIUM, and LONG durations are retrieved
33  * from the chip during initialization with a call to tpm_get_timeouts.
34  */
35 static const u8 tpm1_ordinal_duration[TPM_MAX_ORDINAL] = {
36 	TPM_UNDEFINED,		/* 0 */
37 	TPM_UNDEFINED,
38 	TPM_UNDEFINED,
39 	TPM_UNDEFINED,
40 	TPM_UNDEFINED,
41 	TPM_UNDEFINED,		/* 5 */
42 	TPM_UNDEFINED,
43 	TPM_UNDEFINED,
44 	TPM_UNDEFINED,
45 	TPM_UNDEFINED,
46 	TPM_SHORT,		/* 10 */
47 	TPM_SHORT,
48 	TPM_MEDIUM,
49 	TPM_LONG,
50 	TPM_LONG,
51 	TPM_MEDIUM,		/* 15 */
52 	TPM_SHORT,
53 	TPM_SHORT,
54 	TPM_MEDIUM,
55 	TPM_LONG,
56 	TPM_SHORT,		/* 20 */
57 	TPM_SHORT,
58 	TPM_MEDIUM,
59 	TPM_MEDIUM,
60 	TPM_MEDIUM,
61 	TPM_SHORT,		/* 25 */
62 	TPM_SHORT,
63 	TPM_MEDIUM,
64 	TPM_SHORT,
65 	TPM_SHORT,
66 	TPM_MEDIUM,		/* 30 */
67 	TPM_LONG,
68 	TPM_MEDIUM,
69 	TPM_SHORT,
70 	TPM_SHORT,
71 	TPM_SHORT,		/* 35 */
72 	TPM_MEDIUM,
73 	TPM_MEDIUM,
74 	TPM_UNDEFINED,
75 	TPM_UNDEFINED,
76 	TPM_MEDIUM,		/* 40 */
77 	TPM_LONG,
78 	TPM_MEDIUM,
79 	TPM_SHORT,
80 	TPM_SHORT,
81 	TPM_SHORT,		/* 45 */
82 	TPM_SHORT,
83 	TPM_SHORT,
84 	TPM_SHORT,
85 	TPM_LONG,
86 	TPM_MEDIUM,		/* 50 */
87 	TPM_MEDIUM,
88 	TPM_UNDEFINED,
89 	TPM_UNDEFINED,
90 	TPM_UNDEFINED,
91 	TPM_UNDEFINED,		/* 55 */
92 	TPM_UNDEFINED,
93 	TPM_UNDEFINED,
94 	TPM_UNDEFINED,
95 	TPM_UNDEFINED,
96 	TPM_MEDIUM,		/* 60 */
97 	TPM_MEDIUM,
98 	TPM_MEDIUM,
99 	TPM_SHORT,
100 	TPM_SHORT,
101 	TPM_MEDIUM,		/* 65 */
102 	TPM_UNDEFINED,
103 	TPM_UNDEFINED,
104 	TPM_UNDEFINED,
105 	TPM_UNDEFINED,
106 	TPM_SHORT,		/* 70 */
107 	TPM_SHORT,
108 	TPM_UNDEFINED,
109 	TPM_UNDEFINED,
110 	TPM_UNDEFINED,
111 	TPM_UNDEFINED,		/* 75 */
112 	TPM_UNDEFINED,
113 	TPM_UNDEFINED,
114 	TPM_UNDEFINED,
115 	TPM_UNDEFINED,
116 	TPM_LONG,		/* 80 */
117 	TPM_UNDEFINED,
118 	TPM_MEDIUM,
119 	TPM_LONG,
120 	TPM_SHORT,
121 	TPM_UNDEFINED,		/* 85 */
122 	TPM_UNDEFINED,
123 	TPM_UNDEFINED,
124 	TPM_UNDEFINED,
125 	TPM_UNDEFINED,
126 	TPM_SHORT,		/* 90 */
127 	TPM_SHORT,
128 	TPM_SHORT,
129 	TPM_SHORT,
130 	TPM_SHORT,
131 	TPM_UNDEFINED,		/* 95 */
132 	TPM_UNDEFINED,
133 	TPM_UNDEFINED,
134 	TPM_UNDEFINED,
135 	TPM_UNDEFINED,
136 	TPM_MEDIUM,		/* 100 */
137 	TPM_SHORT,
138 	TPM_SHORT,
139 	TPM_UNDEFINED,
140 	TPM_UNDEFINED,
141 	TPM_UNDEFINED,		/* 105 */
142 	TPM_UNDEFINED,
143 	TPM_UNDEFINED,
144 	TPM_UNDEFINED,
145 	TPM_UNDEFINED,
146 	TPM_SHORT,		/* 110 */
147 	TPM_SHORT,
148 	TPM_SHORT,
149 	TPM_SHORT,
150 	TPM_SHORT,
151 	TPM_SHORT,		/* 115 */
152 	TPM_SHORT,
153 	TPM_SHORT,
154 	TPM_UNDEFINED,
155 	TPM_UNDEFINED,
156 	TPM_LONG,		/* 120 */
157 	TPM_LONG,
158 	TPM_MEDIUM,
159 	TPM_UNDEFINED,
160 	TPM_SHORT,
161 	TPM_SHORT,		/* 125 */
162 	TPM_SHORT,
163 	TPM_LONG,
164 	TPM_SHORT,
165 	TPM_SHORT,
166 	TPM_SHORT,		/* 130 */
167 	TPM_MEDIUM,
168 	TPM_UNDEFINED,
169 	TPM_SHORT,
170 	TPM_MEDIUM,
171 	TPM_UNDEFINED,		/* 135 */
172 	TPM_UNDEFINED,
173 	TPM_UNDEFINED,
174 	TPM_UNDEFINED,
175 	TPM_UNDEFINED,
176 	TPM_SHORT,		/* 140 */
177 	TPM_SHORT,
178 	TPM_UNDEFINED,
179 	TPM_UNDEFINED,
180 	TPM_UNDEFINED,
181 	TPM_UNDEFINED,		/* 145 */
182 	TPM_UNDEFINED,
183 	TPM_UNDEFINED,
184 	TPM_UNDEFINED,
185 	TPM_UNDEFINED,
186 	TPM_SHORT,		/* 150 */
187 	TPM_MEDIUM,
188 	TPM_MEDIUM,
189 	TPM_SHORT,
190 	TPM_SHORT,
191 	TPM_UNDEFINED,		/* 155 */
192 	TPM_UNDEFINED,
193 	TPM_UNDEFINED,
194 	TPM_UNDEFINED,
195 	TPM_UNDEFINED,
196 	TPM_SHORT,		/* 160 */
197 	TPM_SHORT,
198 	TPM_SHORT,
199 	TPM_SHORT,
200 	TPM_UNDEFINED,
201 	TPM_UNDEFINED,		/* 165 */
202 	TPM_UNDEFINED,
203 	TPM_UNDEFINED,
204 	TPM_UNDEFINED,
205 	TPM_UNDEFINED,
206 	TPM_LONG,		/* 170 */
207 	TPM_UNDEFINED,
208 	TPM_UNDEFINED,
209 	TPM_UNDEFINED,
210 	TPM_UNDEFINED,
211 	TPM_UNDEFINED,		/* 175 */
212 	TPM_UNDEFINED,
213 	TPM_UNDEFINED,
214 	TPM_UNDEFINED,
215 	TPM_UNDEFINED,
216 	TPM_MEDIUM,		/* 180 */
217 	TPM_SHORT,
218 	TPM_MEDIUM,
219 	TPM_MEDIUM,
220 	TPM_MEDIUM,
221 	TPM_MEDIUM,		/* 185 */
222 	TPM_SHORT,
223 	TPM_UNDEFINED,
224 	TPM_UNDEFINED,
225 	TPM_UNDEFINED,
226 	TPM_UNDEFINED,		/* 190 */
227 	TPM_UNDEFINED,
228 	TPM_UNDEFINED,
229 	TPM_UNDEFINED,
230 	TPM_UNDEFINED,
231 	TPM_UNDEFINED,		/* 195 */
232 	TPM_UNDEFINED,
233 	TPM_UNDEFINED,
234 	TPM_UNDEFINED,
235 	TPM_UNDEFINED,
236 	TPM_SHORT,		/* 200 */
237 	TPM_UNDEFINED,
238 	TPM_UNDEFINED,
239 	TPM_UNDEFINED,
240 	TPM_SHORT,
241 	TPM_SHORT,		/* 205 */
242 	TPM_SHORT,
243 	TPM_SHORT,
244 	TPM_SHORT,
245 	TPM_SHORT,
246 	TPM_MEDIUM,		/* 210 */
247 	TPM_UNDEFINED,
248 	TPM_MEDIUM,
249 	TPM_MEDIUM,
250 	TPM_MEDIUM,
251 	TPM_UNDEFINED,		/* 215 */
252 	TPM_MEDIUM,
253 	TPM_UNDEFINED,
254 	TPM_UNDEFINED,
255 	TPM_SHORT,
256 	TPM_SHORT,		/* 220 */
257 	TPM_SHORT,
258 	TPM_SHORT,
259 	TPM_SHORT,
260 	TPM_SHORT,
261 	TPM_UNDEFINED,		/* 225 */
262 	TPM_UNDEFINED,
263 	TPM_UNDEFINED,
264 	TPM_UNDEFINED,
265 	TPM_UNDEFINED,
266 	TPM_SHORT,		/* 230 */
267 	TPM_LONG,
268 	TPM_MEDIUM,
269 	TPM_UNDEFINED,
270 	TPM_UNDEFINED,
271 	TPM_UNDEFINED,		/* 235 */
272 	TPM_UNDEFINED,
273 	TPM_UNDEFINED,
274 	TPM_UNDEFINED,
275 	TPM_UNDEFINED,
276 	TPM_SHORT,		/* 240 */
277 	TPM_UNDEFINED,
278 	TPM_MEDIUM,
279 };
280 
281 /**
282  * tpm1_calc_ordinal_duration() - calculate the maximum command duration
283  * @chip:    TPM chip to use.
284  * @ordinal: TPM command ordinal.
285  *
286  * The function returns the maximum amount of time the chip could take
287  * to return the result for a particular ordinal in jiffies.
288  *
289  * Return: A maximal duration time for an ordinal in jiffies.
290  */
291 unsigned long tpm1_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal)
292 {
293 	int duration_idx = TPM_UNDEFINED;
294 	int duration = 0;
295 
296 	/*
297 	 * We only have a duration table for protected commands, where the upper
298 	 * 16 bits are 0. For the few other ordinals the fallback will be used.
299 	 */
300 	if (ordinal < TPM_MAX_ORDINAL)
301 		duration_idx = tpm1_ordinal_duration[ordinal];
302 
303 	if (duration_idx != TPM_UNDEFINED)
304 		duration = chip->duration[duration_idx];
305 	if (duration <= 0)
306 		return 2 * 60 * HZ;
307 	else
308 		return duration;
309 }
310 
311 #define TPM_ORD_STARTUP 153
312 #define TPM_ST_CLEAR 1
313 
314 /**
315  * tpm_startup() - turn on the TPM
316  * @chip: TPM chip to use
317  *
318  * Normally the firmware should start the TPM. This function is provided as a
319  * workaround if this does not happen. A legal case for this could be for
320  * example when a TPM emulator is used.
321  *
322  * Return: same as tpm_transmit_cmd()
323  */
324 static int tpm1_startup(struct tpm_chip *chip)
325 {
326 	struct tpm_buf buf;
327 	int rc;
328 
329 	dev_info(&chip->dev, "starting up the TPM manually\n");
330 
331 	rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_STARTUP);
332 	if (rc < 0)
333 		return rc;
334 
335 	tpm_buf_append_u16(&buf, TPM_ST_CLEAR);
336 
337 	rc = tpm_transmit_cmd(chip, &buf, 0, "attempting to start the TPM");
338 	tpm_buf_destroy(&buf);
339 	return rc;
340 }
341 
342 int tpm1_get_timeouts(struct tpm_chip *chip)
343 {
344 	cap_t cap;
345 	unsigned long timeout_old[4], timeout_chip[4], timeout_eff[4];
346 	ssize_t rc;
347 
348 	rc = tpm1_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, NULL,
349 			 sizeof(cap.timeout));
350 	if (rc == TPM_ERR_INVALID_POSTINIT) {
351 		if (tpm1_startup(chip))
352 			return rc;
353 
354 		rc = tpm1_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap,
355 				 "attempting to determine the timeouts",
356 				 sizeof(cap.timeout));
357 	}
358 
359 	if (rc) {
360 		dev_err(&chip->dev, "A TPM error (%zd) occurred attempting to determine the timeouts\n",
361 			rc);
362 		return rc;
363 	}
364 
365 	timeout_old[0] = jiffies_to_usecs(chip->timeout_a);
366 	timeout_old[1] = jiffies_to_usecs(chip->timeout_b);
367 	timeout_old[2] = jiffies_to_usecs(chip->timeout_c);
368 	timeout_old[3] = jiffies_to_usecs(chip->timeout_d);
369 	timeout_chip[0] = be32_to_cpu(cap.timeout.a);
370 	timeout_chip[1] = be32_to_cpu(cap.timeout.b);
371 	timeout_chip[2] = be32_to_cpu(cap.timeout.c);
372 	timeout_chip[3] = be32_to_cpu(cap.timeout.d);
373 	memcpy(timeout_eff, timeout_chip, sizeof(timeout_eff));
374 
375 	/*
376 	 * Provide ability for vendor overrides of timeout values in case
377 	 * of misreporting.
378 	 */
379 	if (chip->ops->update_timeouts)
380 		chip->ops->update_timeouts(chip, timeout_eff);
381 
382 	if (!chip->timeout_adjusted) {
383 		/* Restore default if chip reported 0 */
384 		unsigned int i;
385 
386 		for (i = 0; i < ARRAY_SIZE(timeout_eff); i++) {
387 			if (timeout_eff[i])
388 				continue;
389 
390 			timeout_eff[i] = timeout_old[i];
391 			chip->timeout_adjusted = true;
392 		}
393 
394 		if (timeout_eff[0] != 0 && timeout_eff[0] < 1000) {
395 			/* timeouts in msec rather usec */
396 			for (i = 0; i != ARRAY_SIZE(timeout_eff); i++)
397 				timeout_eff[i] *= 1000;
398 			chip->timeout_adjusted = true;
399 		}
400 	}
401 
402 	/* Report adjusted timeouts */
403 	if (chip->timeout_adjusted) {
404 		dev_info(&chip->dev, HW_ERR "Adjusting reported timeouts: A %lu->%luus B %lu->%luus C %lu->%luus D %lu->%luus\n",
405 			 timeout_chip[0], timeout_eff[0],
406 			 timeout_chip[1], timeout_eff[1],
407 			 timeout_chip[2], timeout_eff[2],
408 			 timeout_chip[3], timeout_eff[3]);
409 	}
410 
411 	chip->timeout_a = usecs_to_jiffies(timeout_eff[0]);
412 	chip->timeout_b = usecs_to_jiffies(timeout_eff[1]);
413 	chip->timeout_c = usecs_to_jiffies(timeout_eff[2]);
414 	chip->timeout_d = usecs_to_jiffies(timeout_eff[3]);
415 
416 	rc = tpm1_getcap(chip, TPM_CAP_PROP_TIS_DURATION, &cap,
417 			 "attempting to determine the durations",
418 			  sizeof(cap.duration));
419 	if (rc)
420 		return rc;
421 
422 	chip->duration[TPM_SHORT] =
423 		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_short));
424 	chip->duration[TPM_MEDIUM] =
425 		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_medium));
426 	chip->duration[TPM_LONG] =
427 		usecs_to_jiffies(be32_to_cpu(cap.duration.tpm_long));
428 	chip->duration[TPM_LONG_LONG] = 0; /* not used under 1.2 */
429 
430 	/* The Broadcom BCM0102 chipset in a Dell Latitude D820 gets the above
431 	 * value wrong and apparently reports msecs rather than usecs. So we
432 	 * fix up the resulting too-small TPM_SHORT value to make things work.
433 	 * We also scale the TPM_MEDIUM and -_LONG values by 1000.
434 	 */
435 	if (chip->duration[TPM_SHORT] < (HZ / 100)) {
436 		chip->duration[TPM_SHORT] = HZ;
437 		chip->duration[TPM_MEDIUM] *= 1000;
438 		chip->duration[TPM_LONG] *= 1000;
439 		chip->duration_adjusted = true;
440 		dev_info(&chip->dev, "Adjusting TPM timeout parameters.");
441 	}
442 
443 	chip->flags |= TPM_CHIP_FLAG_HAVE_TIMEOUTS;
444 	return 0;
445 }
446 
447 #define TPM_ORD_PCR_EXTEND 20
448 int tpm1_pcr_extend(struct tpm_chip *chip, u32 pcr_idx, const u8 *hash,
449 		    const char *log_msg)
450 {
451 	struct tpm_buf buf;
452 	int rc;
453 
454 	rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_PCR_EXTEND);
455 	if (rc)
456 		return rc;
457 
458 	tpm_buf_append_u32(&buf, pcr_idx);
459 	tpm_buf_append(&buf, hash, TPM_DIGEST_SIZE);
460 
461 	rc = tpm_transmit_cmd(chip, &buf, TPM_DIGEST_SIZE, log_msg);
462 	tpm_buf_destroy(&buf);
463 	return rc;
464 }
465 
466 #define TPM_ORD_GET_CAP 101
467 ssize_t tpm1_getcap(struct tpm_chip *chip, u32 subcap_id, cap_t *cap,
468 		    const char *desc, size_t min_cap_length)
469 {
470 	struct tpm_buf buf;
471 	int rc;
472 
473 	rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_GET_CAP);
474 	if (rc)
475 		return rc;
476 
477 	if (subcap_id == TPM_CAP_VERSION_1_1 ||
478 	    subcap_id == TPM_CAP_VERSION_1_2) {
479 		tpm_buf_append_u32(&buf, subcap_id);
480 		tpm_buf_append_u32(&buf, 0);
481 	} else {
482 		if (subcap_id == TPM_CAP_FLAG_PERM ||
483 		    subcap_id == TPM_CAP_FLAG_VOL)
484 			tpm_buf_append_u32(&buf, TPM_CAP_FLAG);
485 		else
486 			tpm_buf_append_u32(&buf, TPM_CAP_PROP);
487 
488 		tpm_buf_append_u32(&buf, 4);
489 		tpm_buf_append_u32(&buf, subcap_id);
490 	}
491 	rc = tpm_transmit_cmd(chip, &buf, min_cap_length, desc);
492 	if (!rc)
493 		*cap = *(cap_t *)&buf.data[TPM_HEADER_SIZE + 4];
494 	tpm_buf_destroy(&buf);
495 	return rc;
496 }
497 EXPORT_SYMBOL_GPL(tpm1_getcap);
498 
499 #define TPM_ORD_GET_RANDOM 70
500 struct tpm1_get_random_out {
501 	__be32 rng_data_len;
502 	u8 rng_data[TPM_MAX_RNG_DATA];
503 } __packed;
504 
505 /**
506  * tpm1_get_random() - get random bytes from the TPM's RNG
507  * @chip:	a &struct tpm_chip instance
508  * @dest:	destination buffer for the random bytes
509  * @max:	the maximum number of bytes to write to @dest
510  *
511  * Return:
512  * *  number of bytes read
513  * * -errno or a TPM return code otherwise
514  */
515 int tpm1_get_random(struct tpm_chip *chip, u8 *dest, size_t max)
516 {
517 	struct tpm1_get_random_out *out;
518 	u32 num_bytes =  min_t(u32, max, TPM_MAX_RNG_DATA);
519 	struct tpm_buf buf;
520 	u32 total = 0;
521 	int retries = 5;
522 	u32 recd;
523 	int rc;
524 
525 	rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_GET_RANDOM);
526 	if (rc)
527 		return rc;
528 
529 	do {
530 		tpm_buf_append_u32(&buf, num_bytes);
531 
532 		rc = tpm_transmit_cmd(chip, &buf, sizeof(out->rng_data_len),
533 				      "attempting get random");
534 		if (rc)
535 			goto out;
536 
537 		out = (struct tpm1_get_random_out *)&buf.data[TPM_HEADER_SIZE];
538 
539 		recd = be32_to_cpu(out->rng_data_len);
540 		if (recd > num_bytes) {
541 			rc = -EFAULT;
542 			goto out;
543 		}
544 
545 		if (tpm_buf_length(&buf) < TPM_HEADER_SIZE +
546 					   sizeof(out->rng_data_len) + recd) {
547 			rc = -EFAULT;
548 			goto out;
549 		}
550 		memcpy(dest, out->rng_data, recd);
551 
552 		dest += recd;
553 		total += recd;
554 		num_bytes -= recd;
555 
556 		tpm_buf_reset(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_GET_RANDOM);
557 	} while (retries-- && total < max);
558 
559 	rc = total ? (int)total : -EIO;
560 out:
561 	tpm_buf_destroy(&buf);
562 	return rc;
563 }
564 
565 #define TPM_ORD_PCRREAD 21
566 int tpm1_pcr_read(struct tpm_chip *chip, u32 pcr_idx, u8 *res_buf)
567 {
568 	struct tpm_buf buf;
569 	int rc;
570 
571 	rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_PCRREAD);
572 	if (rc)
573 		return rc;
574 
575 	tpm_buf_append_u32(&buf, pcr_idx);
576 
577 	rc = tpm_transmit_cmd(chip, &buf, TPM_DIGEST_SIZE,
578 			      "attempting to read a pcr value");
579 	if (rc)
580 		goto out;
581 
582 	if (tpm_buf_length(&buf) < TPM_DIGEST_SIZE) {
583 		rc = -EFAULT;
584 		goto out;
585 	}
586 
587 	memcpy(res_buf, &buf.data[TPM_HEADER_SIZE], TPM_DIGEST_SIZE);
588 
589 out:
590 	tpm_buf_destroy(&buf);
591 	return rc;
592 }
593 
594 #define TPM_ORD_CONTINUE_SELFTEST 83
595 /**
596  * tpm_continue_selftest() - run TPM's selftest
597  * @chip: TPM chip to use
598  *
599  * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
600  * a TPM error code.
601  */
602 static int tpm1_continue_selftest(struct tpm_chip *chip)
603 {
604 	struct tpm_buf buf;
605 	int rc;
606 
607 	rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_CONTINUE_SELFTEST);
608 	if (rc)
609 		return rc;
610 
611 	rc = tpm_transmit_cmd(chip, &buf, 0, "continue selftest");
612 	tpm_buf_destroy(&buf);
613 	return rc;
614 }
615 
616 /**
617  * tpm1_do_selftest - have the TPM continue its selftest and wait until it
618  *                   can receive further commands
619  * @chip: TPM chip to use
620  *
621  * Returns 0 on success, < 0 in case of fatal error or a value > 0 representing
622  * a TPM error code.
623  */
624 int tpm1_do_selftest(struct tpm_chip *chip)
625 {
626 	int rc;
627 	unsigned int loops;
628 	unsigned int delay_msec = 100;
629 	unsigned long duration;
630 	u8 dummy[TPM_DIGEST_SIZE];
631 
632 	duration = tpm1_calc_ordinal_duration(chip, TPM_ORD_CONTINUE_SELFTEST);
633 
634 	loops = jiffies_to_msecs(duration) / delay_msec;
635 
636 	rc = tpm1_continue_selftest(chip);
637 	if (rc == TPM_ERR_INVALID_POSTINIT) {
638 		chip->flags |= TPM_CHIP_FLAG_ALWAYS_POWERED;
639 		dev_info(&chip->dev, "TPM not ready (%d)\n", rc);
640 	}
641 	/* This may fail if there was no TPM driver during a suspend/resume
642 	 * cycle; some may return 10 (BAD_ORDINAL), others 28 (FAILEDSELFTEST)
643 	 */
644 	if (rc)
645 		return rc;
646 
647 	do {
648 		/* Attempt to read a PCR value */
649 		rc = tpm1_pcr_read(chip, 0, dummy);
650 
651 		/* Some buggy TPMs will not respond to tpm_tis_ready() for
652 		 * around 300ms while the self test is ongoing, keep trying
653 		 * until the self test duration expires.
654 		 */
655 		if (rc == -ETIME) {
656 			dev_info(&chip->dev, HW_ERR "TPM command timed out during continue self test");
657 			tpm_msleep(delay_msec);
658 			continue;
659 		}
660 
661 		if (rc == TPM_ERR_DISABLED || rc == TPM_ERR_DEACTIVATED) {
662 			dev_info(&chip->dev, "TPM is disabled/deactivated (0x%X)\n",
663 				 rc);
664 			/* TPM is disabled and/or deactivated; driver can
665 			 * proceed and TPM does handle commands for
666 			 * suspend/resume correctly
667 			 */
668 			return 0;
669 		}
670 		if (rc != TPM_WARN_DOING_SELFTEST)
671 			return rc;
672 		tpm_msleep(delay_msec);
673 	} while (--loops > 0);
674 
675 	return rc;
676 }
677 EXPORT_SYMBOL_GPL(tpm1_do_selftest);
678 
679 /**
680  * tpm1_auto_startup - Perform the standard automatic TPM initialization
681  *                     sequence
682  * @chip: TPM chip to use
683  *
684  * Returns 0 on success, < 0 in case of fatal error.
685  */
686 int tpm1_auto_startup(struct tpm_chip *chip)
687 {
688 	int rc;
689 
690 	rc = tpm1_get_timeouts(chip);
691 	if (rc)
692 		goto out;
693 	rc = tpm1_do_selftest(chip);
694 	if (rc) {
695 		dev_err(&chip->dev, "TPM self test failed\n");
696 		goto out;
697 	}
698 
699 	chip->allocated_banks = kcalloc(1, sizeof(*chip->allocated_banks),
700 					GFP_KERNEL);
701 	if (!chip->allocated_banks) {
702 		rc = -ENOMEM;
703 		goto out;
704 	}
705 
706 	chip->allocated_banks[0].alg_id = TPM_ALG_SHA1;
707 	chip->allocated_banks[0].digest_size = hash_digest_size[HASH_ALGO_SHA1];
708 	chip->allocated_banks[0].crypto_id = HASH_ALGO_SHA1;
709 	chip->nr_allocated_banks = 1;
710 
711 	return rc;
712 out:
713 	if (rc > 0)
714 		rc = -ENODEV;
715 	return rc;
716 }
717 
718 #define TPM_ORD_SAVESTATE 152
719 
720 /**
721  * tpm1_pm_suspend() - pm suspend handler
722  * @chip: TPM chip to use.
723  * @tpm_suspend_pcr: flush pcr for buggy TPM chips.
724  *
725  * The functions saves the TPM state to be restored on resume.
726  *
727  * Return:
728  * * 0 on success,
729  * * < 0 on error.
730  */
731 int tpm1_pm_suspend(struct tpm_chip *chip, u32 tpm_suspend_pcr)
732 {
733 	u8 dummy_hash[TPM_DIGEST_SIZE] = { 0 };
734 	struct tpm_buf buf;
735 	unsigned int try;
736 	int rc;
737 
738 
739 	/* for buggy tpm, flush pcrs with extend to selected dummy */
740 	if (tpm_suspend_pcr)
741 		rc = tpm1_pcr_extend(chip, tpm_suspend_pcr, dummy_hash,
742 				     "extending dummy pcr before suspend");
743 
744 	rc = tpm_buf_init(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_SAVESTATE);
745 	if (rc)
746 		return rc;
747 	/* now do the actual savestate */
748 	for (try = 0; try < TPM_RETRY; try++) {
749 		rc = tpm_transmit_cmd(chip, &buf, 0, NULL);
750 		/*
751 		 * If the TPM indicates that it is too busy to respond to
752 		 * this command then retry before giving up.  It can take
753 		 * several seconds for this TPM to be ready.
754 		 *
755 		 * This can happen if the TPM has already been sent the
756 		 * SaveState command before the driver has loaded.  TCG 1.2
757 		 * specification states that any communication after SaveState
758 		 * may cause the TPM to invalidate previously saved state.
759 		 */
760 		if (rc != TPM_WARN_RETRY)
761 			break;
762 		tpm_msleep(TPM_TIMEOUT_RETRY);
763 
764 		tpm_buf_reset(&buf, TPM_TAG_RQU_COMMAND, TPM_ORD_SAVESTATE);
765 	}
766 
767 	if (rc)
768 		dev_err(&chip->dev, "Error (%d) sending savestate before suspend\n",
769 			rc);
770 	else if (try > 0)
771 		dev_warn(&chip->dev, "TPM savestate took %dms\n",
772 			 try * TPM_TIMEOUT_RETRY);
773 
774 	tpm_buf_destroy(&buf);
775 
776 	return rc;
777 }
778 
779