xref: /linux/drivers/char/tpm/tpm_tis_core.c (revision e7d759f31ca295d589f7420719c311870bb3166f)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2005, 2006 IBM Corporation
4  * Copyright (C) 2014, 2015 Intel Corporation
5  *
6  * Authors:
7  * Leendert van Doorn <leendert@watson.ibm.com>
8  * Kylene Hall <kjhall@us.ibm.com>
9  *
10  * Maintained by: <tpmdd-devel@lists.sourceforge.net>
11  *
12  * Device driver for TCG/TCPA TPM (trusted platform module).
13  * Specifications at www.trustedcomputinggroup.org
14  *
15  * This device driver implements the TPM interface as defined in
16  * the TCG TPM Interface Spec version 1.2, revision 1.0.
17  */
18 #include <linux/init.h>
19 #include <linux/module.h>
20 #include <linux/moduleparam.h>
21 #include <linux/pnp.h>
22 #include <linux/slab.h>
23 #include <linux/interrupt.h>
24 #include <linux/wait.h>
25 #include <linux/acpi.h>
26 #include <linux/freezer.h>
27 #include <linux/dmi.h>
28 #include "tpm.h"
29 #include "tpm_tis_core.h"
30 
31 #define TPM_TIS_MAX_UNHANDLED_IRQS	1000
32 
33 static void tpm_tis_clkrun_enable(struct tpm_chip *chip, bool value);
34 
35 static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask,
36 					bool check_cancel, bool *canceled)
37 {
38 	u8 status = chip->ops->status(chip);
39 
40 	*canceled = false;
41 	if ((status & mask) == mask)
42 		return true;
43 	if (check_cancel && chip->ops->req_canceled(chip, status)) {
44 		*canceled = true;
45 		return true;
46 	}
47 	return false;
48 }
49 
50 static u8 tpm_tis_filter_sts_mask(u8 int_mask, u8 sts_mask)
51 {
52 	if (!(int_mask & TPM_INTF_STS_VALID_INT))
53 		sts_mask &= ~TPM_STS_VALID;
54 
55 	if (!(int_mask & TPM_INTF_DATA_AVAIL_INT))
56 		sts_mask &= ~TPM_STS_DATA_AVAIL;
57 
58 	if (!(int_mask & TPM_INTF_CMD_READY_INT))
59 		sts_mask &= ~TPM_STS_COMMAND_READY;
60 
61 	return sts_mask;
62 }
63 
64 static int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask,
65 		unsigned long timeout, wait_queue_head_t *queue,
66 		bool check_cancel)
67 {
68 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
69 	unsigned long stop;
70 	long rc;
71 	u8 status;
72 	bool canceled = false;
73 	u8 sts_mask;
74 	int ret = 0;
75 
76 	/* check current status */
77 	status = chip->ops->status(chip);
78 	if ((status & mask) == mask)
79 		return 0;
80 
81 	sts_mask = mask & (TPM_STS_VALID | TPM_STS_DATA_AVAIL |
82 			   TPM_STS_COMMAND_READY);
83 	/* check what status changes can be handled by irqs */
84 	sts_mask = tpm_tis_filter_sts_mask(priv->int_mask, sts_mask);
85 
86 	stop = jiffies + timeout;
87 	/* process status changes with irq support */
88 	if (sts_mask) {
89 		ret = -ETIME;
90 again:
91 		timeout = stop - jiffies;
92 		if ((long)timeout <= 0)
93 			return -ETIME;
94 		rc = wait_event_interruptible_timeout(*queue,
95 			wait_for_tpm_stat_cond(chip, sts_mask, check_cancel,
96 					       &canceled),
97 			timeout);
98 		if (rc > 0) {
99 			if (canceled)
100 				return -ECANCELED;
101 			ret = 0;
102 		}
103 		if (rc == -ERESTARTSYS && freezing(current)) {
104 			clear_thread_flag(TIF_SIGPENDING);
105 			goto again;
106 		}
107 	}
108 
109 	if (ret)
110 		return ret;
111 
112 	mask &= ~sts_mask;
113 	if (!mask) /* all done */
114 		return 0;
115 	/* process status changes without irq support */
116 	do {
117 		status = chip->ops->status(chip);
118 		if ((status & mask) == mask)
119 			return 0;
120 		usleep_range(priv->timeout_min,
121 			     priv->timeout_max);
122 	} while (time_before(jiffies, stop));
123 	return -ETIME;
124 }
125 
126 /* Before we attempt to access the TPM we must see that the valid bit is set.
127  * The specification says that this bit is 0 at reset and remains 0 until the
128  * 'TPM has gone through its self test and initialization and has established
129  * correct values in the other bits.'
130  */
131 static int wait_startup(struct tpm_chip *chip, int l)
132 {
133 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
134 	unsigned long stop = jiffies + chip->timeout_a;
135 
136 	do {
137 		int rc;
138 		u8 access;
139 
140 		rc = tpm_tis_read8(priv, TPM_ACCESS(l), &access);
141 		if (rc < 0)
142 			return rc;
143 
144 		if (access & TPM_ACCESS_VALID)
145 			return 0;
146 		tpm_msleep(TPM_TIMEOUT);
147 	} while (time_before(jiffies, stop));
148 	return -1;
149 }
150 
151 static bool check_locality(struct tpm_chip *chip, int l)
152 {
153 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
154 	int rc;
155 	u8 access;
156 
157 	rc = tpm_tis_read8(priv, TPM_ACCESS(l), &access);
158 	if (rc < 0)
159 		return false;
160 
161 	if ((access & (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID
162 		       | TPM_ACCESS_REQUEST_USE)) ==
163 	    (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) {
164 		priv->locality = l;
165 		return true;
166 	}
167 
168 	return false;
169 }
170 
171 static int __tpm_tis_relinquish_locality(struct tpm_tis_data *priv, int l)
172 {
173 	tpm_tis_write8(priv, TPM_ACCESS(l), TPM_ACCESS_ACTIVE_LOCALITY);
174 
175 	return 0;
176 }
177 
178 static int tpm_tis_relinquish_locality(struct tpm_chip *chip, int l)
179 {
180 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
181 
182 	mutex_lock(&priv->locality_count_mutex);
183 	priv->locality_count--;
184 	if (priv->locality_count == 0)
185 		__tpm_tis_relinquish_locality(priv, l);
186 	mutex_unlock(&priv->locality_count_mutex);
187 
188 	return 0;
189 }
190 
191 static int __tpm_tis_request_locality(struct tpm_chip *chip, int l)
192 {
193 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
194 	unsigned long stop, timeout;
195 	long rc;
196 
197 	if (check_locality(chip, l))
198 		return l;
199 
200 	rc = tpm_tis_write8(priv, TPM_ACCESS(l), TPM_ACCESS_REQUEST_USE);
201 	if (rc < 0)
202 		return rc;
203 
204 	stop = jiffies + chip->timeout_a;
205 
206 	if (chip->flags & TPM_CHIP_FLAG_IRQ) {
207 again:
208 		timeout = stop - jiffies;
209 		if ((long)timeout <= 0)
210 			return -1;
211 		rc = wait_event_interruptible_timeout(priv->int_queue,
212 						      (check_locality
213 						       (chip, l)),
214 						      timeout);
215 		if (rc > 0)
216 			return l;
217 		if (rc == -ERESTARTSYS && freezing(current)) {
218 			clear_thread_flag(TIF_SIGPENDING);
219 			goto again;
220 		}
221 	} else {
222 		/* wait for burstcount */
223 		do {
224 			if (check_locality(chip, l))
225 				return l;
226 			tpm_msleep(TPM_TIMEOUT);
227 		} while (time_before(jiffies, stop));
228 	}
229 	return -1;
230 }
231 
232 static int tpm_tis_request_locality(struct tpm_chip *chip, int l)
233 {
234 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
235 	int ret = 0;
236 
237 	mutex_lock(&priv->locality_count_mutex);
238 	if (priv->locality_count == 0)
239 		ret = __tpm_tis_request_locality(chip, l);
240 	if (!ret)
241 		priv->locality_count++;
242 	mutex_unlock(&priv->locality_count_mutex);
243 	return ret;
244 }
245 
246 static u8 tpm_tis_status(struct tpm_chip *chip)
247 {
248 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
249 	int rc;
250 	u8 status;
251 
252 	rc = tpm_tis_read8(priv, TPM_STS(priv->locality), &status);
253 	if (rc < 0)
254 		return 0;
255 
256 	if (unlikely((status & TPM_STS_READ_ZERO) != 0)) {
257 		if  (!test_and_set_bit(TPM_TIS_INVALID_STATUS, &priv->flags)) {
258 			/*
259 			 * If this trips, the chances are the read is
260 			 * returning 0xff because the locality hasn't been
261 			 * acquired.  Usually because tpm_try_get_ops() hasn't
262 			 * been called before doing a TPM operation.
263 			 */
264 			dev_err(&chip->dev, "invalid TPM_STS.x 0x%02x, dumping stack for forensics\n",
265 				status);
266 
267 			/*
268 			 * Dump stack for forensics, as invalid TPM_STS.x could be
269 			 * potentially triggered by impaired tpm_try_get_ops() or
270 			 * tpm_find_get_ops().
271 			 */
272 			dump_stack();
273 		}
274 
275 		return 0;
276 	}
277 
278 	return status;
279 }
280 
281 static void tpm_tis_ready(struct tpm_chip *chip)
282 {
283 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
284 
285 	/* this causes the current command to be aborted */
286 	tpm_tis_write8(priv, TPM_STS(priv->locality), TPM_STS_COMMAND_READY);
287 }
288 
289 static int get_burstcount(struct tpm_chip *chip)
290 {
291 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
292 	unsigned long stop;
293 	int burstcnt, rc;
294 	u32 value;
295 
296 	/* wait for burstcount */
297 	if (chip->flags & TPM_CHIP_FLAG_TPM2)
298 		stop = jiffies + chip->timeout_a;
299 	else
300 		stop = jiffies + chip->timeout_d;
301 	do {
302 		rc = tpm_tis_read32(priv, TPM_STS(priv->locality), &value);
303 		if (rc < 0)
304 			return rc;
305 
306 		burstcnt = (value >> 8) & 0xFFFF;
307 		if (burstcnt)
308 			return burstcnt;
309 		usleep_range(TPM_TIMEOUT_USECS_MIN, TPM_TIMEOUT_USECS_MAX);
310 	} while (time_before(jiffies, stop));
311 	return -EBUSY;
312 }
313 
314 static int recv_data(struct tpm_chip *chip, u8 *buf, size_t count)
315 {
316 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
317 	int size = 0, burstcnt, rc;
318 
319 	while (size < count) {
320 		rc = wait_for_tpm_stat(chip,
321 				 TPM_STS_DATA_AVAIL | TPM_STS_VALID,
322 				 chip->timeout_c,
323 				 &priv->read_queue, true);
324 		if (rc < 0)
325 			return rc;
326 		burstcnt = get_burstcount(chip);
327 		if (burstcnt < 0) {
328 			dev_err(&chip->dev, "Unable to read burstcount\n");
329 			return burstcnt;
330 		}
331 		burstcnt = min_t(int, burstcnt, count - size);
332 
333 		rc = tpm_tis_read_bytes(priv, TPM_DATA_FIFO(priv->locality),
334 					burstcnt, buf + size);
335 		if (rc < 0)
336 			return rc;
337 
338 		size += burstcnt;
339 	}
340 	return size;
341 }
342 
343 static int tpm_tis_try_recv(struct tpm_chip *chip, u8 *buf, size_t count)
344 {
345 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
346 	int size = 0;
347 	int status;
348 	u32 expected;
349 	int rc;
350 
351 	size = recv_data(chip, buf, TPM_HEADER_SIZE);
352 	/* read first 10 bytes, including tag, paramsize, and result */
353 	if (size < TPM_HEADER_SIZE) {
354 		dev_err(&chip->dev, "Unable to read header\n");
355 		goto out;
356 	}
357 
358 	expected = be32_to_cpu(*(__be32 *) (buf + 2));
359 	if (expected > count || expected < TPM_HEADER_SIZE) {
360 		size = -EIO;
361 		goto out;
362 	}
363 
364 	rc = recv_data(chip, &buf[TPM_HEADER_SIZE],
365 		       expected - TPM_HEADER_SIZE);
366 	if (rc < 0) {
367 		size = rc;
368 		goto out;
369 	}
370 	size += rc;
371 	if (size < expected) {
372 		dev_err(&chip->dev, "Unable to read remainder of result\n");
373 		size = -ETIME;
374 		goto out;
375 	}
376 
377 	if (wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c,
378 				&priv->int_queue, false) < 0) {
379 		size = -ETIME;
380 		goto out;
381 	}
382 	status = tpm_tis_status(chip);
383 	if (status & TPM_STS_DATA_AVAIL) {
384 		dev_err(&chip->dev, "Error left over data\n");
385 		size = -EIO;
386 		goto out;
387 	}
388 
389 	rc = tpm_tis_verify_crc(priv, (size_t)size, buf);
390 	if (rc < 0) {
391 		dev_err(&chip->dev, "CRC mismatch for response.\n");
392 		size = rc;
393 		goto out;
394 	}
395 
396 out:
397 	return size;
398 }
399 
400 static int tpm_tis_recv(struct tpm_chip *chip, u8 *buf, size_t count)
401 {
402 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
403 	unsigned int try;
404 	int rc = 0;
405 
406 	if (count < TPM_HEADER_SIZE)
407 		return -EIO;
408 
409 	for (try = 0; try < TPM_RETRY; try++) {
410 		rc = tpm_tis_try_recv(chip, buf, count);
411 
412 		if (rc == -EIO)
413 			/* Data transfer errors, indicated by EIO, can be
414 			 * recovered by rereading the response.
415 			 */
416 			tpm_tis_write8(priv, TPM_STS(priv->locality),
417 				       TPM_STS_RESPONSE_RETRY);
418 		else
419 			break;
420 	}
421 
422 	tpm_tis_ready(chip);
423 
424 	return rc;
425 }
426 
427 /*
428  * If interrupts are used (signaled by an irq set in the vendor structure)
429  * tpm.c can skip polling for the data to be available as the interrupt is
430  * waited for here
431  */
432 static int tpm_tis_send_data(struct tpm_chip *chip, const u8 *buf, size_t len)
433 {
434 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
435 	int rc, status, burstcnt;
436 	size_t count = 0;
437 	bool itpm = test_bit(TPM_TIS_ITPM_WORKAROUND, &priv->flags);
438 
439 	status = tpm_tis_status(chip);
440 	if ((status & TPM_STS_COMMAND_READY) == 0) {
441 		tpm_tis_ready(chip);
442 		if (wait_for_tpm_stat
443 		    (chip, TPM_STS_COMMAND_READY, chip->timeout_b,
444 		     &priv->int_queue, false) < 0) {
445 			rc = -ETIME;
446 			goto out_err;
447 		}
448 	}
449 
450 	while (count < len - 1) {
451 		burstcnt = get_burstcount(chip);
452 		if (burstcnt < 0) {
453 			dev_err(&chip->dev, "Unable to read burstcount\n");
454 			rc = burstcnt;
455 			goto out_err;
456 		}
457 		burstcnt = min_t(int, burstcnt, len - count - 1);
458 		rc = tpm_tis_write_bytes(priv, TPM_DATA_FIFO(priv->locality),
459 					 burstcnt, buf + count);
460 		if (rc < 0)
461 			goto out_err;
462 
463 		count += burstcnt;
464 
465 		if (wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c,
466 					&priv->int_queue, false) < 0) {
467 			rc = -ETIME;
468 			goto out_err;
469 		}
470 		status = tpm_tis_status(chip);
471 		if (!itpm && (status & TPM_STS_DATA_EXPECT) == 0) {
472 			rc = -EIO;
473 			goto out_err;
474 		}
475 	}
476 
477 	/* write last byte */
478 	rc = tpm_tis_write8(priv, TPM_DATA_FIFO(priv->locality), buf[count]);
479 	if (rc < 0)
480 		goto out_err;
481 
482 	if (wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c,
483 				&priv->int_queue, false) < 0) {
484 		rc = -ETIME;
485 		goto out_err;
486 	}
487 	status = tpm_tis_status(chip);
488 	if (!itpm && (status & TPM_STS_DATA_EXPECT) != 0) {
489 		rc = -EIO;
490 		goto out_err;
491 	}
492 
493 	rc = tpm_tis_verify_crc(priv, len, buf);
494 	if (rc < 0) {
495 		dev_err(&chip->dev, "CRC mismatch for command.\n");
496 		goto out_err;
497 	}
498 
499 	return 0;
500 
501 out_err:
502 	tpm_tis_ready(chip);
503 	return rc;
504 }
505 
506 static void __tpm_tis_disable_interrupts(struct tpm_chip *chip)
507 {
508 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
509 	u32 int_mask = 0;
510 
511 	tpm_tis_read32(priv, TPM_INT_ENABLE(priv->locality), &int_mask);
512 	int_mask &= ~TPM_GLOBAL_INT_ENABLE;
513 	tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality), int_mask);
514 
515 	chip->flags &= ~TPM_CHIP_FLAG_IRQ;
516 }
517 
518 static void tpm_tis_disable_interrupts(struct tpm_chip *chip)
519 {
520 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
521 
522 	if (priv->irq == 0)
523 		return;
524 
525 	__tpm_tis_disable_interrupts(chip);
526 
527 	devm_free_irq(chip->dev.parent, priv->irq, chip);
528 	priv->irq = 0;
529 }
530 
531 /*
532  * If interrupts are used (signaled by an irq set in the vendor structure)
533  * tpm.c can skip polling for the data to be available as the interrupt is
534  * waited for here
535  */
536 static int tpm_tis_send_main(struct tpm_chip *chip, const u8 *buf, size_t len)
537 {
538 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
539 	int rc;
540 	u32 ordinal;
541 	unsigned long dur;
542 	unsigned int try;
543 
544 	for (try = 0; try < TPM_RETRY; try++) {
545 		rc = tpm_tis_send_data(chip, buf, len);
546 		if (rc >= 0)
547 			/* Data transfer done successfully */
548 			break;
549 		else if (rc != -EIO)
550 			/* Data transfer failed, not recoverable */
551 			return rc;
552 	}
553 
554 	/* go and do it */
555 	rc = tpm_tis_write8(priv, TPM_STS(priv->locality), TPM_STS_GO);
556 	if (rc < 0)
557 		goto out_err;
558 
559 	if (chip->flags & TPM_CHIP_FLAG_IRQ) {
560 		ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
561 
562 		dur = tpm_calc_ordinal_duration(chip, ordinal);
563 		if (wait_for_tpm_stat
564 		    (chip, TPM_STS_DATA_AVAIL | TPM_STS_VALID, dur,
565 		     &priv->read_queue, false) < 0) {
566 			rc = -ETIME;
567 			goto out_err;
568 		}
569 	}
570 	return 0;
571 out_err:
572 	tpm_tis_ready(chip);
573 	return rc;
574 }
575 
576 static int tpm_tis_send(struct tpm_chip *chip, u8 *buf, size_t len)
577 {
578 	int rc, irq;
579 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
580 
581 	if (!(chip->flags & TPM_CHIP_FLAG_IRQ) ||
582 	     test_bit(TPM_TIS_IRQ_TESTED, &priv->flags))
583 		return tpm_tis_send_main(chip, buf, len);
584 
585 	/* Verify receipt of the expected IRQ */
586 	irq = priv->irq;
587 	priv->irq = 0;
588 	chip->flags &= ~TPM_CHIP_FLAG_IRQ;
589 	rc = tpm_tis_send_main(chip, buf, len);
590 	priv->irq = irq;
591 	chip->flags |= TPM_CHIP_FLAG_IRQ;
592 	if (!test_bit(TPM_TIS_IRQ_TESTED, &priv->flags))
593 		tpm_msleep(1);
594 	if (!test_bit(TPM_TIS_IRQ_TESTED, &priv->flags))
595 		tpm_tis_disable_interrupts(chip);
596 	set_bit(TPM_TIS_IRQ_TESTED, &priv->flags);
597 	return rc;
598 }
599 
600 struct tis_vendor_durations_override {
601 	u32 did_vid;
602 	struct tpm1_version version;
603 	unsigned long durations[3];
604 };
605 
606 static const struct  tis_vendor_durations_override vendor_dur_overrides[] = {
607 	/* STMicroelectronics 0x104a */
608 	{ 0x0000104a,
609 	  { 1, 2, 8, 28 },
610 	  { (2 * 60 * HZ), (2 * 60 * HZ), (2 * 60 * HZ) } },
611 };
612 
613 static void tpm_tis_update_durations(struct tpm_chip *chip,
614 				     unsigned long *duration_cap)
615 {
616 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
617 	struct tpm1_version *version;
618 	u32 did_vid;
619 	int i, rc;
620 	cap_t cap;
621 
622 	chip->duration_adjusted = false;
623 
624 	if (chip->ops->clk_enable != NULL)
625 		chip->ops->clk_enable(chip, true);
626 
627 	rc = tpm_tis_read32(priv, TPM_DID_VID(0), &did_vid);
628 	if (rc < 0) {
629 		dev_warn(&chip->dev, "%s: failed to read did_vid. %d\n",
630 			 __func__, rc);
631 		goto out;
632 	}
633 
634 	/* Try to get a TPM version 1.2 or 1.1 TPM_CAP_VERSION_INFO */
635 	rc = tpm1_getcap(chip, TPM_CAP_VERSION_1_2, &cap,
636 			 "attempting to determine the 1.2 version",
637 			 sizeof(cap.version2));
638 	if (!rc) {
639 		version = &cap.version2.version;
640 	} else {
641 		rc = tpm1_getcap(chip, TPM_CAP_VERSION_1_1, &cap,
642 				 "attempting to determine the 1.1 version",
643 				 sizeof(cap.version1));
644 
645 		if (rc)
646 			goto out;
647 
648 		version = &cap.version1;
649 	}
650 
651 	for (i = 0; i != ARRAY_SIZE(vendor_dur_overrides); i++) {
652 		if (vendor_dur_overrides[i].did_vid != did_vid)
653 			continue;
654 
655 		if ((version->major ==
656 		     vendor_dur_overrides[i].version.major) &&
657 		    (version->minor ==
658 		     vendor_dur_overrides[i].version.minor) &&
659 		    (version->rev_major ==
660 		     vendor_dur_overrides[i].version.rev_major) &&
661 		    (version->rev_minor ==
662 		     vendor_dur_overrides[i].version.rev_minor)) {
663 
664 			memcpy(duration_cap,
665 			       vendor_dur_overrides[i].durations,
666 			       sizeof(vendor_dur_overrides[i].durations));
667 
668 			chip->duration_adjusted = true;
669 			goto out;
670 		}
671 	}
672 
673 out:
674 	if (chip->ops->clk_enable != NULL)
675 		chip->ops->clk_enable(chip, false);
676 }
677 
678 struct tis_vendor_timeout_override {
679 	u32 did_vid;
680 	unsigned long timeout_us[4];
681 };
682 
683 static const struct tis_vendor_timeout_override vendor_timeout_overrides[] = {
684 	/* Atmel 3204 */
685 	{ 0x32041114, { (TIS_SHORT_TIMEOUT*1000), (TIS_LONG_TIMEOUT*1000),
686 			(TIS_SHORT_TIMEOUT*1000), (TIS_SHORT_TIMEOUT*1000) } },
687 };
688 
689 static void tpm_tis_update_timeouts(struct tpm_chip *chip,
690 				    unsigned long *timeout_cap)
691 {
692 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
693 	int i, rc;
694 	u32 did_vid;
695 
696 	chip->timeout_adjusted = false;
697 
698 	if (chip->ops->clk_enable != NULL)
699 		chip->ops->clk_enable(chip, true);
700 
701 	rc = tpm_tis_read32(priv, TPM_DID_VID(0), &did_vid);
702 	if (rc < 0) {
703 		dev_warn(&chip->dev, "%s: failed to read did_vid: %d\n",
704 			 __func__, rc);
705 		goto out;
706 	}
707 
708 	for (i = 0; i != ARRAY_SIZE(vendor_timeout_overrides); i++) {
709 		if (vendor_timeout_overrides[i].did_vid != did_vid)
710 			continue;
711 		memcpy(timeout_cap, vendor_timeout_overrides[i].timeout_us,
712 		       sizeof(vendor_timeout_overrides[i].timeout_us));
713 		chip->timeout_adjusted = true;
714 	}
715 
716 out:
717 	if (chip->ops->clk_enable != NULL)
718 		chip->ops->clk_enable(chip, false);
719 
720 	return;
721 }
722 
723 /*
724  * Early probing for iTPM with STS_DATA_EXPECT flaw.
725  * Try sending command without itpm flag set and if that
726  * fails, repeat with itpm flag set.
727  */
728 static int probe_itpm(struct tpm_chip *chip)
729 {
730 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
731 	int rc = 0;
732 	static const u8 cmd_getticks[] = {
733 		0x00, 0xc1, 0x00, 0x00, 0x00, 0x0a,
734 		0x00, 0x00, 0x00, 0xf1
735 	};
736 	size_t len = sizeof(cmd_getticks);
737 	u16 vendor;
738 
739 	if (test_bit(TPM_TIS_ITPM_WORKAROUND, &priv->flags))
740 		return 0;
741 
742 	rc = tpm_tis_read16(priv, TPM_DID_VID(0), &vendor);
743 	if (rc < 0)
744 		return rc;
745 
746 	/* probe only iTPMS */
747 	if (vendor != TPM_VID_INTEL)
748 		return 0;
749 
750 	if (tpm_tis_request_locality(chip, 0) != 0)
751 		return -EBUSY;
752 
753 	rc = tpm_tis_send_data(chip, cmd_getticks, len);
754 	if (rc == 0)
755 		goto out;
756 
757 	tpm_tis_ready(chip);
758 
759 	set_bit(TPM_TIS_ITPM_WORKAROUND, &priv->flags);
760 
761 	rc = tpm_tis_send_data(chip, cmd_getticks, len);
762 	if (rc == 0)
763 		dev_info(&chip->dev, "Detected an iTPM.\n");
764 	else {
765 		clear_bit(TPM_TIS_ITPM_WORKAROUND, &priv->flags);
766 		rc = -EFAULT;
767 	}
768 
769 out:
770 	tpm_tis_ready(chip);
771 	tpm_tis_relinquish_locality(chip, priv->locality);
772 
773 	return rc;
774 }
775 
776 static bool tpm_tis_req_canceled(struct tpm_chip *chip, u8 status)
777 {
778 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
779 
780 	if (!test_bit(TPM_TIS_DEFAULT_CANCELLATION, &priv->flags)) {
781 		switch (priv->manufacturer_id) {
782 		case TPM_VID_WINBOND:
783 			return ((status == TPM_STS_VALID) ||
784 				(status == (TPM_STS_VALID | TPM_STS_COMMAND_READY)));
785 		case TPM_VID_STM:
786 			return (status == (TPM_STS_VALID | TPM_STS_COMMAND_READY));
787 		default:
788 			break;
789 		}
790 	}
791 
792 	return status == TPM_STS_COMMAND_READY;
793 }
794 
795 static irqreturn_t tpm_tis_revert_interrupts(struct tpm_chip *chip)
796 {
797 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
798 	const char *product;
799 	const char *vendor;
800 
801 	dev_warn(&chip->dev, FW_BUG
802 		 "TPM interrupt storm detected, polling instead\n");
803 
804 	vendor = dmi_get_system_info(DMI_SYS_VENDOR);
805 	product = dmi_get_system_info(DMI_PRODUCT_VERSION);
806 
807 	if (vendor && product) {
808 		dev_info(&chip->dev,
809 			"Consider adding the following entry to tpm_tis_dmi_table:\n");
810 		dev_info(&chip->dev, "\tDMI_SYS_VENDOR: %s\n", vendor);
811 		dev_info(&chip->dev, "\tDMI_PRODUCT_VERSION: %s\n", product);
812 	}
813 
814 	if (tpm_tis_request_locality(chip, 0) != 0)
815 		return IRQ_NONE;
816 
817 	__tpm_tis_disable_interrupts(chip);
818 	tpm_tis_relinquish_locality(chip, 0);
819 
820 	schedule_work(&priv->free_irq_work);
821 
822 	return IRQ_HANDLED;
823 }
824 
825 static irqreturn_t tpm_tis_update_unhandled_irqs(struct tpm_chip *chip)
826 {
827 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
828 	irqreturn_t irqret = IRQ_HANDLED;
829 
830 	if (!(chip->flags & TPM_CHIP_FLAG_IRQ))
831 		return IRQ_HANDLED;
832 
833 	if (time_after(jiffies, priv->last_unhandled_irq + HZ/10))
834 		priv->unhandled_irqs = 1;
835 	else
836 		priv->unhandled_irqs++;
837 
838 	priv->last_unhandled_irq = jiffies;
839 
840 	if (priv->unhandled_irqs > TPM_TIS_MAX_UNHANDLED_IRQS)
841 		irqret = tpm_tis_revert_interrupts(chip);
842 
843 	return irqret;
844 }
845 
846 static irqreturn_t tis_int_handler(int dummy, void *dev_id)
847 {
848 	struct tpm_chip *chip = dev_id;
849 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
850 	u32 interrupt;
851 	int rc;
852 
853 	rc = tpm_tis_read32(priv, TPM_INT_STATUS(priv->locality), &interrupt);
854 	if (rc < 0)
855 		goto err;
856 
857 	if (interrupt == 0)
858 		goto err;
859 
860 	set_bit(TPM_TIS_IRQ_TESTED, &priv->flags);
861 	if (interrupt & TPM_INTF_DATA_AVAIL_INT)
862 		wake_up_interruptible(&priv->read_queue);
863 
864 	if (interrupt &
865 	    (TPM_INTF_LOCALITY_CHANGE_INT | TPM_INTF_STS_VALID_INT |
866 	     TPM_INTF_CMD_READY_INT))
867 		wake_up_interruptible(&priv->int_queue);
868 
869 	/* Clear interrupts handled with TPM_EOI */
870 	tpm_tis_request_locality(chip, 0);
871 	rc = tpm_tis_write32(priv, TPM_INT_STATUS(priv->locality), interrupt);
872 	tpm_tis_relinquish_locality(chip, 0);
873 	if (rc < 0)
874 		goto err;
875 
876 	tpm_tis_read32(priv, TPM_INT_STATUS(priv->locality), &interrupt);
877 	return IRQ_HANDLED;
878 
879 err:
880 	return tpm_tis_update_unhandled_irqs(chip);
881 }
882 
883 static void tpm_tis_gen_interrupt(struct tpm_chip *chip)
884 {
885 	const char *desc = "attempting to generate an interrupt";
886 	u32 cap2;
887 	cap_t cap;
888 	int ret;
889 
890 	chip->flags |= TPM_CHIP_FLAG_IRQ;
891 
892 	if (chip->flags & TPM_CHIP_FLAG_TPM2)
893 		ret = tpm2_get_tpm_pt(chip, 0x100, &cap2, desc);
894 	else
895 		ret = tpm1_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, desc, 0);
896 
897 	if (ret)
898 		chip->flags &= ~TPM_CHIP_FLAG_IRQ;
899 }
900 
901 static void tpm_tis_free_irq_func(struct work_struct *work)
902 {
903 	struct tpm_tis_data *priv = container_of(work, typeof(*priv), free_irq_work);
904 	struct tpm_chip *chip = priv->chip;
905 
906 	devm_free_irq(chip->dev.parent, priv->irq, chip);
907 	priv->irq = 0;
908 }
909 
910 /* Register the IRQ and issue a command that will cause an interrupt. If an
911  * irq is seen then leave the chip setup for IRQ operation, otherwise reverse
912  * everything and leave in polling mode. Returns 0 on success.
913  */
914 static int tpm_tis_probe_irq_single(struct tpm_chip *chip, u32 intmask,
915 				    int flags, int irq)
916 {
917 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
918 	u8 original_int_vec;
919 	int rc;
920 	u32 int_status;
921 
922 	INIT_WORK(&priv->free_irq_work, tpm_tis_free_irq_func);
923 
924 	rc = devm_request_threaded_irq(chip->dev.parent, irq, NULL,
925 				       tis_int_handler, IRQF_ONESHOT | flags,
926 				       dev_name(&chip->dev), chip);
927 	if (rc) {
928 		dev_info(&chip->dev, "Unable to request irq: %d for probe\n",
929 			 irq);
930 		return -1;
931 	}
932 	priv->irq = irq;
933 
934 	rc = tpm_tis_request_locality(chip, 0);
935 	if (rc < 0)
936 		return rc;
937 
938 	rc = tpm_tis_read8(priv, TPM_INT_VECTOR(priv->locality),
939 			   &original_int_vec);
940 	if (rc < 0) {
941 		tpm_tis_relinquish_locality(chip, priv->locality);
942 		return rc;
943 	}
944 
945 	rc = tpm_tis_write8(priv, TPM_INT_VECTOR(priv->locality), irq);
946 	if (rc < 0)
947 		goto restore_irqs;
948 
949 	rc = tpm_tis_read32(priv, TPM_INT_STATUS(priv->locality), &int_status);
950 	if (rc < 0)
951 		goto restore_irqs;
952 
953 	/* Clear all existing */
954 	rc = tpm_tis_write32(priv, TPM_INT_STATUS(priv->locality), int_status);
955 	if (rc < 0)
956 		goto restore_irqs;
957 	/* Turn on */
958 	rc = tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality),
959 			     intmask | TPM_GLOBAL_INT_ENABLE);
960 	if (rc < 0)
961 		goto restore_irqs;
962 
963 	clear_bit(TPM_TIS_IRQ_TESTED, &priv->flags);
964 
965 	/* Generate an interrupt by having the core call through to
966 	 * tpm_tis_send
967 	 */
968 	tpm_tis_gen_interrupt(chip);
969 
970 restore_irqs:
971 	/* tpm_tis_send will either confirm the interrupt is working or it
972 	 * will call disable_irq which undoes all of the above.
973 	 */
974 	if (!(chip->flags & TPM_CHIP_FLAG_IRQ)) {
975 		tpm_tis_write8(priv, original_int_vec,
976 			       TPM_INT_VECTOR(priv->locality));
977 		rc = -1;
978 	}
979 
980 	tpm_tis_relinquish_locality(chip, priv->locality);
981 
982 	return rc;
983 }
984 
985 /* Try to find the IRQ the TPM is using. This is for legacy x86 systems that
986  * do not have ACPI/etc. We typically expect the interrupt to be declared if
987  * present.
988  */
989 static void tpm_tis_probe_irq(struct tpm_chip *chip, u32 intmask)
990 {
991 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
992 	u8 original_int_vec;
993 	int i, rc;
994 
995 	rc = tpm_tis_read8(priv, TPM_INT_VECTOR(priv->locality),
996 			   &original_int_vec);
997 	if (rc < 0)
998 		return;
999 
1000 	if (!original_int_vec) {
1001 		if (IS_ENABLED(CONFIG_X86))
1002 			for (i = 3; i <= 15; i++)
1003 				if (!tpm_tis_probe_irq_single(chip, intmask, 0,
1004 							      i))
1005 					return;
1006 	} else if (!tpm_tis_probe_irq_single(chip, intmask, 0,
1007 					     original_int_vec))
1008 		return;
1009 }
1010 
1011 void tpm_tis_remove(struct tpm_chip *chip)
1012 {
1013 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
1014 	u32 reg = TPM_INT_ENABLE(priv->locality);
1015 	u32 interrupt;
1016 	int rc;
1017 
1018 	tpm_tis_clkrun_enable(chip, true);
1019 
1020 	rc = tpm_tis_read32(priv, reg, &interrupt);
1021 	if (rc < 0)
1022 		interrupt = 0;
1023 
1024 	tpm_tis_write32(priv, reg, ~TPM_GLOBAL_INT_ENABLE & interrupt);
1025 	flush_work(&priv->free_irq_work);
1026 
1027 	tpm_tis_clkrun_enable(chip, false);
1028 
1029 	if (priv->ilb_base_addr)
1030 		iounmap(priv->ilb_base_addr);
1031 }
1032 EXPORT_SYMBOL_GPL(tpm_tis_remove);
1033 
1034 /**
1035  * tpm_tis_clkrun_enable() - Keep clkrun protocol disabled for entire duration
1036  *                           of a single TPM command
1037  * @chip:	TPM chip to use
1038  * @value:	1 - Disable CLKRUN protocol, so that clocks are free running
1039  *		0 - Enable CLKRUN protocol
1040  * Call this function directly in tpm_tis_remove() in error or driver removal
1041  * path, since the chip->ops is set to NULL in tpm_chip_unregister().
1042  */
1043 static void tpm_tis_clkrun_enable(struct tpm_chip *chip, bool value)
1044 {
1045 	struct tpm_tis_data *data = dev_get_drvdata(&chip->dev);
1046 	u32 clkrun_val;
1047 
1048 	if (!IS_ENABLED(CONFIG_X86) || !is_bsw() ||
1049 	    !data->ilb_base_addr)
1050 		return;
1051 
1052 	if (value) {
1053 		data->clkrun_enabled++;
1054 		if (data->clkrun_enabled > 1)
1055 			return;
1056 		clkrun_val = ioread32(data->ilb_base_addr + LPC_CNTRL_OFFSET);
1057 
1058 		/* Disable LPC CLKRUN# */
1059 		clkrun_val &= ~LPC_CLKRUN_EN;
1060 		iowrite32(clkrun_val, data->ilb_base_addr + LPC_CNTRL_OFFSET);
1061 
1062 		/*
1063 		 * Write any random value on port 0x80 which is on LPC, to make
1064 		 * sure LPC clock is running before sending any TPM command.
1065 		 */
1066 		outb(0xCC, 0x80);
1067 	} else {
1068 		data->clkrun_enabled--;
1069 		if (data->clkrun_enabled)
1070 			return;
1071 
1072 		clkrun_val = ioread32(data->ilb_base_addr + LPC_CNTRL_OFFSET);
1073 
1074 		/* Enable LPC CLKRUN# */
1075 		clkrun_val |= LPC_CLKRUN_EN;
1076 		iowrite32(clkrun_val, data->ilb_base_addr + LPC_CNTRL_OFFSET);
1077 
1078 		/*
1079 		 * Write any random value on port 0x80 which is on LPC, to make
1080 		 * sure LPC clock is running before sending any TPM command.
1081 		 */
1082 		outb(0xCC, 0x80);
1083 	}
1084 }
1085 
1086 static const struct tpm_class_ops tpm_tis = {
1087 	.flags = TPM_OPS_AUTO_STARTUP,
1088 	.status = tpm_tis_status,
1089 	.recv = tpm_tis_recv,
1090 	.send = tpm_tis_send,
1091 	.cancel = tpm_tis_ready,
1092 	.update_timeouts = tpm_tis_update_timeouts,
1093 	.update_durations = tpm_tis_update_durations,
1094 	.req_complete_mask = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
1095 	.req_complete_val = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
1096 	.req_canceled = tpm_tis_req_canceled,
1097 	.request_locality = tpm_tis_request_locality,
1098 	.relinquish_locality = tpm_tis_relinquish_locality,
1099 	.clk_enable = tpm_tis_clkrun_enable,
1100 };
1101 
1102 int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
1103 		      const struct tpm_tis_phy_ops *phy_ops,
1104 		      acpi_handle acpi_dev_handle)
1105 {
1106 	u32 vendor;
1107 	u32 intfcaps;
1108 	u32 intmask;
1109 	u32 clkrun_val;
1110 	u8 rid;
1111 	int rc, probe;
1112 	struct tpm_chip *chip;
1113 
1114 	chip = tpmm_chip_alloc(dev, &tpm_tis);
1115 	if (IS_ERR(chip))
1116 		return PTR_ERR(chip);
1117 
1118 #ifdef CONFIG_ACPI
1119 	chip->acpi_dev_handle = acpi_dev_handle;
1120 #endif
1121 
1122 	chip->hwrng.quality = priv->rng_quality;
1123 
1124 	/* Maximum timeouts */
1125 	chip->timeout_a = msecs_to_jiffies(TIS_TIMEOUT_A_MAX);
1126 	chip->timeout_b = msecs_to_jiffies(TIS_TIMEOUT_B_MAX);
1127 	chip->timeout_c = msecs_to_jiffies(TIS_TIMEOUT_C_MAX);
1128 	chip->timeout_d = msecs_to_jiffies(TIS_TIMEOUT_D_MAX);
1129 	priv->chip = chip;
1130 	priv->timeout_min = TPM_TIMEOUT_USECS_MIN;
1131 	priv->timeout_max = TPM_TIMEOUT_USECS_MAX;
1132 	priv->phy_ops = phy_ops;
1133 	priv->locality_count = 0;
1134 	mutex_init(&priv->locality_count_mutex);
1135 
1136 	dev_set_drvdata(&chip->dev, priv);
1137 
1138 	rc = tpm_tis_read32(priv, TPM_DID_VID(0), &vendor);
1139 	if (rc < 0)
1140 		return rc;
1141 
1142 	priv->manufacturer_id = vendor;
1143 
1144 	if (priv->manufacturer_id == TPM_VID_ATML &&
1145 		!(chip->flags & TPM_CHIP_FLAG_TPM2)) {
1146 		priv->timeout_min = TIS_TIMEOUT_MIN_ATML;
1147 		priv->timeout_max = TIS_TIMEOUT_MAX_ATML;
1148 	}
1149 
1150 	if (is_bsw()) {
1151 		priv->ilb_base_addr = ioremap(INTEL_LEGACY_BLK_BASE_ADDR,
1152 					ILB_REMAP_SIZE);
1153 		if (!priv->ilb_base_addr)
1154 			return -ENOMEM;
1155 
1156 		clkrun_val = ioread32(priv->ilb_base_addr + LPC_CNTRL_OFFSET);
1157 		/* Check if CLKRUN# is already not enabled in the LPC bus */
1158 		if (!(clkrun_val & LPC_CLKRUN_EN)) {
1159 			iounmap(priv->ilb_base_addr);
1160 			priv->ilb_base_addr = NULL;
1161 		}
1162 	}
1163 
1164 	if (chip->ops->clk_enable != NULL)
1165 		chip->ops->clk_enable(chip, true);
1166 
1167 	if (wait_startup(chip, 0) != 0) {
1168 		rc = -ENODEV;
1169 		goto out_err;
1170 	}
1171 
1172 	/* Take control of the TPM's interrupt hardware and shut it off */
1173 	rc = tpm_tis_read32(priv, TPM_INT_ENABLE(priv->locality), &intmask);
1174 	if (rc < 0)
1175 		goto out_err;
1176 
1177 	/* Figure out the capabilities */
1178 	rc = tpm_tis_read32(priv, TPM_INTF_CAPS(priv->locality), &intfcaps);
1179 	if (rc < 0)
1180 		goto out_err;
1181 
1182 	dev_dbg(dev, "TPM interface capabilities (0x%x):\n",
1183 		intfcaps);
1184 	if (intfcaps & TPM_INTF_BURST_COUNT_STATIC)
1185 		dev_dbg(dev, "\tBurst Count Static\n");
1186 	if (intfcaps & TPM_INTF_CMD_READY_INT) {
1187 		intmask |= TPM_INTF_CMD_READY_INT;
1188 		dev_dbg(dev, "\tCommand Ready Int Support\n");
1189 	}
1190 	if (intfcaps & TPM_INTF_INT_EDGE_FALLING)
1191 		dev_dbg(dev, "\tInterrupt Edge Falling\n");
1192 	if (intfcaps & TPM_INTF_INT_EDGE_RISING)
1193 		dev_dbg(dev, "\tInterrupt Edge Rising\n");
1194 	if (intfcaps & TPM_INTF_INT_LEVEL_LOW)
1195 		dev_dbg(dev, "\tInterrupt Level Low\n");
1196 	if (intfcaps & TPM_INTF_INT_LEVEL_HIGH)
1197 		dev_dbg(dev, "\tInterrupt Level High\n");
1198 	if (intfcaps & TPM_INTF_LOCALITY_CHANGE_INT) {
1199 		intmask |= TPM_INTF_LOCALITY_CHANGE_INT;
1200 		dev_dbg(dev, "\tLocality Change Int Support\n");
1201 	}
1202 	if (intfcaps & TPM_INTF_STS_VALID_INT) {
1203 		intmask |= TPM_INTF_STS_VALID_INT;
1204 		dev_dbg(dev, "\tSts Valid Int Support\n");
1205 	}
1206 	if (intfcaps & TPM_INTF_DATA_AVAIL_INT) {
1207 		intmask |= TPM_INTF_DATA_AVAIL_INT;
1208 		dev_dbg(dev, "\tData Avail Int Support\n");
1209 	}
1210 
1211 	intmask &= ~TPM_GLOBAL_INT_ENABLE;
1212 
1213 	rc = tpm_tis_request_locality(chip, 0);
1214 	if (rc < 0) {
1215 		rc = -ENODEV;
1216 		goto out_err;
1217 	}
1218 
1219 	tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality), intmask);
1220 	tpm_tis_relinquish_locality(chip, 0);
1221 
1222 	rc = tpm_chip_start(chip);
1223 	if (rc)
1224 		goto out_err;
1225 	rc = tpm2_probe(chip);
1226 	tpm_chip_stop(chip);
1227 	if (rc)
1228 		goto out_err;
1229 
1230 	rc = tpm_tis_read8(priv, TPM_RID(0), &rid);
1231 	if (rc < 0)
1232 		goto out_err;
1233 
1234 	dev_info(dev, "%s TPM (device-id 0x%X, rev-id %d)\n",
1235 		 (chip->flags & TPM_CHIP_FLAG_TPM2) ? "2.0" : "1.2",
1236 		 vendor >> 16, rid);
1237 
1238 	probe = probe_itpm(chip);
1239 	if (probe < 0) {
1240 		rc = -ENODEV;
1241 		goto out_err;
1242 	}
1243 
1244 	/* INTERRUPT Setup */
1245 	init_waitqueue_head(&priv->read_queue);
1246 	init_waitqueue_head(&priv->int_queue);
1247 
1248 	rc = tpm_chip_bootstrap(chip);
1249 	if (rc)
1250 		goto out_err;
1251 
1252 	if (irq != -1) {
1253 		/*
1254 		 * Before doing irq testing issue a command to the TPM in polling mode
1255 		 * to make sure it works. May as well use that command to set the
1256 		 * proper timeouts for the driver.
1257 		 */
1258 
1259 		rc = tpm_tis_request_locality(chip, 0);
1260 		if (rc < 0)
1261 			goto out_err;
1262 
1263 		rc = tpm_get_timeouts(chip);
1264 
1265 		tpm_tis_relinquish_locality(chip, 0);
1266 
1267 		if (rc) {
1268 			dev_err(dev, "Could not get TPM timeouts and durations\n");
1269 			rc = -ENODEV;
1270 			goto out_err;
1271 		}
1272 
1273 		if (irq)
1274 			tpm_tis_probe_irq_single(chip, intmask, IRQF_SHARED,
1275 						 irq);
1276 		else
1277 			tpm_tis_probe_irq(chip, intmask);
1278 
1279 		if (chip->flags & TPM_CHIP_FLAG_IRQ) {
1280 			priv->int_mask = intmask;
1281 		} else {
1282 			dev_err(&chip->dev, FW_BUG
1283 					"TPM interrupt not working, polling instead\n");
1284 
1285 			rc = tpm_tis_request_locality(chip, 0);
1286 			if (rc < 0)
1287 				goto out_err;
1288 			tpm_tis_disable_interrupts(chip);
1289 			tpm_tis_relinquish_locality(chip, 0);
1290 		}
1291 	}
1292 
1293 	rc = tpm_chip_register(chip);
1294 	if (rc)
1295 		goto out_err;
1296 
1297 	if (chip->ops->clk_enable != NULL)
1298 		chip->ops->clk_enable(chip, false);
1299 
1300 	return 0;
1301 out_err:
1302 	if (chip->ops->clk_enable != NULL)
1303 		chip->ops->clk_enable(chip, false);
1304 
1305 	tpm_tis_remove(chip);
1306 
1307 	return rc;
1308 }
1309 EXPORT_SYMBOL_GPL(tpm_tis_core_init);
1310 
1311 #ifdef CONFIG_PM_SLEEP
1312 static void tpm_tis_reenable_interrupts(struct tpm_chip *chip)
1313 {
1314 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
1315 	u32 intmask;
1316 	int rc;
1317 
1318 	/*
1319 	 * Re-enable interrupts that device may have lost or BIOS/firmware may
1320 	 * have disabled.
1321 	 */
1322 	rc = tpm_tis_write8(priv, TPM_INT_VECTOR(priv->locality), priv->irq);
1323 	if (rc < 0) {
1324 		dev_err(&chip->dev, "Setting IRQ failed.\n");
1325 		return;
1326 	}
1327 
1328 	intmask = priv->int_mask | TPM_GLOBAL_INT_ENABLE;
1329 	rc = tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality), intmask);
1330 	if (rc < 0)
1331 		dev_err(&chip->dev, "Enabling interrupts failed.\n");
1332 }
1333 
1334 int tpm_tis_resume(struct device *dev)
1335 {
1336 	struct tpm_chip *chip = dev_get_drvdata(dev);
1337 	int ret;
1338 
1339 	ret = tpm_chip_start(chip);
1340 	if (ret)
1341 		return ret;
1342 
1343 	if (chip->flags & TPM_CHIP_FLAG_IRQ)
1344 		tpm_tis_reenable_interrupts(chip);
1345 
1346 	/*
1347 	 * TPM 1.2 requires self-test on resume. This function actually returns
1348 	 * an error code but for unknown reason it isn't handled.
1349 	 */
1350 	if (!(chip->flags & TPM_CHIP_FLAG_TPM2))
1351 		tpm1_do_selftest(chip);
1352 
1353 	tpm_chip_stop(chip);
1354 
1355 	ret = tpm_pm_resume(dev);
1356 	if (ret)
1357 		return ret;
1358 
1359 	return 0;
1360 }
1361 EXPORT_SYMBOL_GPL(tpm_tis_resume);
1362 #endif
1363 
1364 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1365 MODULE_DESCRIPTION("TPM Driver");
1366 MODULE_VERSION("2.0");
1367 MODULE_LICENSE("GPL");
1368