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