xref: /openbmc/linux/drivers/char/tpm/tpm_tis_core.c (revision 0edbfea5)
1 /*
2  * Copyright (C) 2005, 2006 IBM Corporation
3  * Copyright (C) 2014, 2015 Intel Corporation
4  *
5  * Authors:
6  * Leendert van Doorn <leendert@watson.ibm.com>
7  * Kylene Hall <kjhall@us.ibm.com>
8  *
9  * Maintained by: <tpmdd-devel@lists.sourceforge.net>
10  *
11  * Device driver for TCG/TCPA TPM (trusted platform module).
12  * Specifications at www.trustedcomputinggroup.org
13  *
14  * This device driver implements the TPM interface as defined in
15  * the TCG TPM Interface Spec version 1.2, revision 1.0.
16  *
17  * This program is free software; you can redistribute it and/or
18  * modify it under the terms of the GNU General Public License as
19  * published by the Free Software Foundation, version 2 of the
20  * License.
21  */
22 #include <linux/init.h>
23 #include <linux/module.h>
24 #include <linux/moduleparam.h>
25 #include <linux/pnp.h>
26 #include <linux/slab.h>
27 #include <linux/interrupt.h>
28 #include <linux/wait.h>
29 #include <linux/acpi.h>
30 #include <linux/freezer.h>
31 #include "tpm.h"
32 #include "tpm_tis_core.h"
33 
34 /* Before we attempt to access the TPM we must see that the valid bit is set.
35  * The specification says that this bit is 0 at reset and remains 0 until the
36  * 'TPM has gone through its self test and initialization and has established
37  * correct values in the other bits.'
38  */
39 static int wait_startup(struct tpm_chip *chip, int l)
40 {
41 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
42 	unsigned long stop = jiffies + chip->timeout_a;
43 
44 	do {
45 		int rc;
46 		u8 access;
47 
48 		rc = tpm_tis_read8(priv, TPM_ACCESS(l), &access);
49 		if (rc < 0)
50 			return rc;
51 
52 		if (access & TPM_ACCESS_VALID)
53 			return 0;
54 		msleep(TPM_TIMEOUT);
55 	} while (time_before(jiffies, stop));
56 	return -1;
57 }
58 
59 static int check_locality(struct tpm_chip *chip, int l)
60 {
61 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
62 	int rc;
63 	u8 access;
64 
65 	rc = tpm_tis_read8(priv, TPM_ACCESS(l), &access);
66 	if (rc < 0)
67 		return rc;
68 
69 	if ((access & (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) ==
70 	    (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID))
71 		return priv->locality = l;
72 
73 	return -1;
74 }
75 
76 static void release_locality(struct tpm_chip *chip, int l, int force)
77 {
78 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
79 	int rc;
80 	u8 access;
81 
82 	rc = tpm_tis_read8(priv, TPM_ACCESS(l), &access);
83 	if (rc < 0)
84 		return;
85 
86 	if (force || (access &
87 		      (TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID)) ==
88 	    (TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID))
89 		tpm_tis_write8(priv, TPM_ACCESS(l), TPM_ACCESS_ACTIVE_LOCALITY);
90 
91 }
92 
93 static int request_locality(struct tpm_chip *chip, int l)
94 {
95 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
96 	unsigned long stop, timeout;
97 	long rc;
98 
99 	if (check_locality(chip, l) >= 0)
100 		return l;
101 
102 	rc = tpm_tis_write8(priv, TPM_ACCESS(l), TPM_ACCESS_REQUEST_USE);
103 	if (rc < 0)
104 		return rc;
105 
106 	stop = jiffies + chip->timeout_a;
107 
108 	if (chip->flags & TPM_CHIP_FLAG_IRQ) {
109 again:
110 		timeout = stop - jiffies;
111 		if ((long)timeout <= 0)
112 			return -1;
113 		rc = wait_event_interruptible_timeout(priv->int_queue,
114 						      (check_locality
115 						       (chip, l) >= 0),
116 						      timeout);
117 		if (rc > 0)
118 			return l;
119 		if (rc == -ERESTARTSYS && freezing(current)) {
120 			clear_thread_flag(TIF_SIGPENDING);
121 			goto again;
122 		}
123 	} else {
124 		/* wait for burstcount */
125 		do {
126 			if (check_locality(chip, l) >= 0)
127 				return l;
128 			msleep(TPM_TIMEOUT);
129 		} while (time_before(jiffies, stop));
130 	}
131 	return -1;
132 }
133 
134 static u8 tpm_tis_status(struct tpm_chip *chip)
135 {
136 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
137 	int rc;
138 	u8 status;
139 
140 	rc = tpm_tis_read8(priv, TPM_STS(priv->locality), &status);
141 	if (rc < 0)
142 		return 0;
143 
144 	return status;
145 }
146 
147 static void tpm_tis_ready(struct tpm_chip *chip)
148 {
149 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
150 
151 	/* this causes the current command to be aborted */
152 	tpm_tis_write8(priv, TPM_STS(priv->locality), TPM_STS_COMMAND_READY);
153 }
154 
155 static int get_burstcount(struct tpm_chip *chip)
156 {
157 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
158 	unsigned long stop;
159 	int burstcnt, rc;
160 	u8 value;
161 
162 	/* wait for burstcount */
163 	/* which timeout value, spec has 2 answers (c & d) */
164 	stop = jiffies + chip->timeout_d;
165 	do {
166 		rc = tpm_tis_read8(priv, TPM_STS(priv->locality) + 1, &value);
167 		if (rc < 0)
168 			return rc;
169 
170 		burstcnt = value;
171 		rc = tpm_tis_read8(priv, TPM_STS(priv->locality) + 2, &value);
172 		if (rc < 0)
173 			return rc;
174 
175 		burstcnt += value << 8;
176 		if (burstcnt)
177 			return burstcnt;
178 		msleep(TPM_TIMEOUT);
179 	} while (time_before(jiffies, stop));
180 	return -EBUSY;
181 }
182 
183 static int recv_data(struct tpm_chip *chip, u8 *buf, size_t count)
184 {
185 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
186 	int size = 0, burstcnt, rc;
187 
188 	while (size < count &&
189 	       wait_for_tpm_stat(chip,
190 				 TPM_STS_DATA_AVAIL | TPM_STS_VALID,
191 				 chip->timeout_c,
192 				 &priv->read_queue, true) == 0) {
193 		burstcnt = min_t(int, get_burstcount(chip), count - size);
194 
195 		rc = tpm_tis_read_bytes(priv, TPM_DATA_FIFO(priv->locality),
196 					burstcnt, buf + size);
197 		if (rc < 0)
198 			return rc;
199 
200 		size += burstcnt;
201 	}
202 	return size;
203 }
204 
205 static int tpm_tis_recv(struct tpm_chip *chip, u8 *buf, size_t count)
206 {
207 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
208 	int size = 0;
209 	int expected, status;
210 
211 	if (count < TPM_HEADER_SIZE) {
212 		size = -EIO;
213 		goto out;
214 	}
215 
216 	size = recv_data(chip, buf, TPM_HEADER_SIZE);
217 	/* read first 10 bytes, including tag, paramsize, and result */
218 	if (size < TPM_HEADER_SIZE) {
219 		dev_err(&chip->dev, "Unable to read header\n");
220 		goto out;
221 	}
222 
223 	expected = be32_to_cpu(*(__be32 *) (buf + 2));
224 	if (expected > count) {
225 		size = -EIO;
226 		goto out;
227 	}
228 
229 	size += recv_data(chip, &buf[TPM_HEADER_SIZE],
230 			  expected - TPM_HEADER_SIZE);
231 	if (size < expected) {
232 		dev_err(&chip->dev, "Unable to read remainder of result\n");
233 		size = -ETIME;
234 		goto out;
235 	}
236 
237 	wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c,
238 			  &priv->int_queue, false);
239 	status = tpm_tis_status(chip);
240 	if (status & TPM_STS_DATA_AVAIL) {	/* retry? */
241 		dev_err(&chip->dev, "Error left over data\n");
242 		size = -EIO;
243 		goto out;
244 	}
245 
246 out:
247 	tpm_tis_ready(chip);
248 	release_locality(chip, priv->locality, 0);
249 	return size;
250 }
251 
252 /*
253  * If interrupts are used (signaled by an irq set in the vendor structure)
254  * tpm.c can skip polling for the data to be available as the interrupt is
255  * waited for here
256  */
257 static int tpm_tis_send_data(struct tpm_chip *chip, u8 *buf, size_t len)
258 {
259 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
260 	int rc, status, burstcnt;
261 	size_t count = 0;
262 	bool itpm = priv->flags & TPM_TIS_ITPM_POSSIBLE;
263 
264 	if (request_locality(chip, 0) < 0)
265 		return -EBUSY;
266 
267 	status = tpm_tis_status(chip);
268 	if ((status & TPM_STS_COMMAND_READY) == 0) {
269 		tpm_tis_ready(chip);
270 		if (wait_for_tpm_stat
271 		    (chip, TPM_STS_COMMAND_READY, chip->timeout_b,
272 		     &priv->int_queue, false) < 0) {
273 			rc = -ETIME;
274 			goto out_err;
275 		}
276 	}
277 
278 	while (count < len - 1) {
279 		burstcnt = min_t(int, get_burstcount(chip), len - count - 1);
280 		rc = tpm_tis_write_bytes(priv, TPM_DATA_FIFO(priv->locality),
281 					 burstcnt, buf + count);
282 		if (rc < 0)
283 			goto out_err;
284 
285 		count += burstcnt;
286 
287 		wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c,
288 				  &priv->int_queue, false);
289 		status = tpm_tis_status(chip);
290 		if (!itpm && (status & TPM_STS_DATA_EXPECT) == 0) {
291 			rc = -EIO;
292 			goto out_err;
293 		}
294 	}
295 
296 	/* write last byte */
297 	rc = tpm_tis_write8(priv, TPM_DATA_FIFO(priv->locality), buf[count]);
298 	if (rc < 0)
299 		goto out_err;
300 
301 	wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c,
302 			  &priv->int_queue, false);
303 	status = tpm_tis_status(chip);
304 	if (!itpm && (status & TPM_STS_DATA_EXPECT) != 0) {
305 		rc = -EIO;
306 		goto out_err;
307 	}
308 
309 	return 0;
310 
311 out_err:
312 	tpm_tis_ready(chip);
313 	release_locality(chip, priv->locality, 0);
314 	return rc;
315 }
316 
317 static void disable_interrupts(struct tpm_chip *chip)
318 {
319 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
320 	u32 intmask;
321 	int rc;
322 
323 	rc = tpm_tis_read32(priv, TPM_INT_ENABLE(priv->locality), &intmask);
324 	if (rc < 0)
325 		intmask = 0;
326 
327 	intmask &= ~TPM_GLOBAL_INT_ENABLE;
328 	rc = tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality), intmask);
329 
330 	devm_free_irq(chip->dev.parent, priv->irq, chip);
331 	priv->irq = 0;
332 	chip->flags &= ~TPM_CHIP_FLAG_IRQ;
333 }
334 
335 /*
336  * If interrupts are used (signaled by an irq set in the vendor structure)
337  * tpm.c can skip polling for the data to be available as the interrupt is
338  * waited for here
339  */
340 static int tpm_tis_send_main(struct tpm_chip *chip, u8 *buf, size_t len)
341 {
342 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
343 	int rc;
344 	u32 ordinal;
345 	unsigned long dur;
346 
347 	rc = tpm_tis_send_data(chip, buf, len);
348 	if (rc < 0)
349 		return rc;
350 
351 	/* go and do it */
352 	rc = tpm_tis_write8(priv, TPM_STS(priv->locality), TPM_STS_GO);
353 	if (rc < 0)
354 		goto out_err;
355 
356 	if (chip->flags & TPM_CHIP_FLAG_IRQ) {
357 		ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
358 
359 		if (chip->flags & TPM_CHIP_FLAG_TPM2)
360 			dur = tpm2_calc_ordinal_duration(chip, ordinal);
361 		else
362 			dur = tpm_calc_ordinal_duration(chip, ordinal);
363 
364 		if (wait_for_tpm_stat
365 		    (chip, TPM_STS_DATA_AVAIL | TPM_STS_VALID, dur,
366 		     &priv->read_queue, false) < 0) {
367 			rc = -ETIME;
368 			goto out_err;
369 		}
370 	}
371 	return len;
372 out_err:
373 	tpm_tis_ready(chip);
374 	release_locality(chip, priv->locality, 0);
375 	return rc;
376 }
377 
378 static int tpm_tis_send(struct tpm_chip *chip, u8 *buf, size_t len)
379 {
380 	int rc, irq;
381 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
382 
383 	if (!(chip->flags & TPM_CHIP_FLAG_IRQ) || priv->irq_tested)
384 		return tpm_tis_send_main(chip, buf, len);
385 
386 	/* Verify receipt of the expected IRQ */
387 	irq = priv->irq;
388 	priv->irq = 0;
389 	chip->flags &= ~TPM_CHIP_FLAG_IRQ;
390 	rc = tpm_tis_send_main(chip, buf, len);
391 	priv->irq = irq;
392 	chip->flags |= TPM_CHIP_FLAG_IRQ;
393 	if (!priv->irq_tested)
394 		msleep(1);
395 	if (!priv->irq_tested)
396 		disable_interrupts(chip);
397 	priv->irq_tested = true;
398 	return rc;
399 }
400 
401 struct tis_vendor_timeout_override {
402 	u32 did_vid;
403 	unsigned long timeout_us[4];
404 };
405 
406 static const struct tis_vendor_timeout_override vendor_timeout_overrides[] = {
407 	/* Atmel 3204 */
408 	{ 0x32041114, { (TIS_SHORT_TIMEOUT*1000), (TIS_LONG_TIMEOUT*1000),
409 			(TIS_SHORT_TIMEOUT*1000), (TIS_SHORT_TIMEOUT*1000) } },
410 };
411 
412 static bool tpm_tis_update_timeouts(struct tpm_chip *chip,
413 				    unsigned long *timeout_cap)
414 {
415 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
416 	int i, rc;
417 	u32 did_vid;
418 
419 	rc = tpm_tis_read32(priv, TPM_DID_VID(0), &did_vid);
420 	if (rc < 0)
421 		return rc;
422 
423 	for (i = 0; i != ARRAY_SIZE(vendor_timeout_overrides); i++) {
424 		if (vendor_timeout_overrides[i].did_vid != did_vid)
425 			continue;
426 		memcpy(timeout_cap, vendor_timeout_overrides[i].timeout_us,
427 		       sizeof(vendor_timeout_overrides[i].timeout_us));
428 		return true;
429 	}
430 
431 	return false;
432 }
433 
434 /*
435  * Early probing for iTPM with STS_DATA_EXPECT flaw.
436  * Try sending command without itpm flag set and if that
437  * fails, repeat with itpm flag set.
438  */
439 static int probe_itpm(struct tpm_chip *chip)
440 {
441 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
442 	int rc = 0;
443 	u8 cmd_getticks[] = {
444 		0x00, 0xc1, 0x00, 0x00, 0x00, 0x0a,
445 		0x00, 0x00, 0x00, 0xf1
446 	};
447 	size_t len = sizeof(cmd_getticks);
448 	bool itpm;
449 	u16 vendor;
450 
451 	rc = tpm_tis_read16(priv, TPM_DID_VID(0), &vendor);
452 	if (rc < 0)
453 		return rc;
454 
455 	/* probe only iTPMS */
456 	if (vendor != TPM_VID_INTEL)
457 		return 0;
458 
459 	itpm = false;
460 
461 	rc = tpm_tis_send_data(chip, cmd_getticks, len);
462 	if (rc == 0)
463 		goto out;
464 
465 	tpm_tis_ready(chip);
466 	release_locality(chip, priv->locality, 0);
467 
468 	itpm = true;
469 
470 	rc = tpm_tis_send_data(chip, cmd_getticks, len);
471 	if (rc == 0) {
472 		dev_info(&chip->dev, "Detected an iTPM.\n");
473 		rc = 1;
474 	} else
475 		rc = -EFAULT;
476 
477 out:
478 	tpm_tis_ready(chip);
479 	release_locality(chip, priv->locality, 0);
480 
481 	return rc;
482 }
483 
484 static bool tpm_tis_req_canceled(struct tpm_chip *chip, u8 status)
485 {
486 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
487 
488 	switch (priv->manufacturer_id) {
489 	case TPM_VID_WINBOND:
490 		return ((status == TPM_STS_VALID) ||
491 			(status == (TPM_STS_VALID | TPM_STS_COMMAND_READY)));
492 	case TPM_VID_STM:
493 		return (status == (TPM_STS_VALID | TPM_STS_COMMAND_READY));
494 	default:
495 		return (status == TPM_STS_COMMAND_READY);
496 	}
497 }
498 
499 static irqreturn_t tis_int_handler(int dummy, void *dev_id)
500 {
501 	struct tpm_chip *chip = dev_id;
502 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
503 	u32 interrupt;
504 	int i, rc;
505 
506 	rc = tpm_tis_read32(priv, TPM_INT_STATUS(priv->locality), &interrupt);
507 	if (rc < 0)
508 		return IRQ_NONE;
509 
510 	if (interrupt == 0)
511 		return IRQ_NONE;
512 
513 	priv->irq_tested = true;
514 	if (interrupt & TPM_INTF_DATA_AVAIL_INT)
515 		wake_up_interruptible(&priv->read_queue);
516 	if (interrupt & TPM_INTF_LOCALITY_CHANGE_INT)
517 		for (i = 0; i < 5; i++)
518 			if (check_locality(chip, i) >= 0)
519 				break;
520 	if (interrupt &
521 	    (TPM_INTF_LOCALITY_CHANGE_INT | TPM_INTF_STS_VALID_INT |
522 	     TPM_INTF_CMD_READY_INT))
523 		wake_up_interruptible(&priv->int_queue);
524 
525 	/* Clear interrupts handled with TPM_EOI */
526 	rc = tpm_tis_write32(priv, TPM_INT_STATUS(priv->locality), interrupt);
527 	if (rc < 0)
528 		return IRQ_NONE;
529 
530 	tpm_tis_read32(priv, TPM_INT_STATUS(priv->locality), &interrupt);
531 	return IRQ_HANDLED;
532 }
533 
534 /* Register the IRQ and issue a command that will cause an interrupt. If an
535  * irq is seen then leave the chip setup for IRQ operation, otherwise reverse
536  * everything and leave in polling mode. Returns 0 on success.
537  */
538 static int tpm_tis_probe_irq_single(struct tpm_chip *chip, u32 intmask,
539 				    int flags, int irq)
540 {
541 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
542 	u8 original_int_vec;
543 	int rc;
544 	u32 int_status;
545 
546 	if (devm_request_irq(chip->dev.parent, irq, tis_int_handler, flags,
547 			     dev_name(&chip->dev), chip) != 0) {
548 		dev_info(&chip->dev, "Unable to request irq: %d for probe\n",
549 			 irq);
550 		return -1;
551 	}
552 	priv->irq = irq;
553 
554 	rc = tpm_tis_read8(priv, TPM_INT_VECTOR(priv->locality),
555 			   &original_int_vec);
556 	if (rc < 0)
557 		return rc;
558 
559 	rc = tpm_tis_write8(priv, TPM_INT_VECTOR(priv->locality), irq);
560 	if (rc < 0)
561 		return rc;
562 
563 	rc = tpm_tis_read32(priv, TPM_INT_STATUS(priv->locality), &int_status);
564 	if (rc < 0)
565 		return rc;
566 
567 	/* Clear all existing */
568 	rc = tpm_tis_write32(priv, TPM_INT_STATUS(priv->locality), int_status);
569 	if (rc < 0)
570 		return rc;
571 
572 	/* Turn on */
573 	rc = tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality),
574 			     intmask | TPM_GLOBAL_INT_ENABLE);
575 	if (rc < 0)
576 		return rc;
577 
578 	priv->irq_tested = false;
579 
580 	/* Generate an interrupt by having the core call through to
581 	 * tpm_tis_send
582 	 */
583 	if (chip->flags & TPM_CHIP_FLAG_TPM2)
584 		tpm2_gen_interrupt(chip);
585 	else
586 		tpm_gen_interrupt(chip);
587 
588 	/* tpm_tis_send will either confirm the interrupt is working or it
589 	 * will call disable_irq which undoes all of the above.
590 	 */
591 	if (!(chip->flags & TPM_CHIP_FLAG_IRQ)) {
592 		rc = tpm_tis_write8(priv, original_int_vec,
593 				TPM_INT_VECTOR(priv->locality));
594 		if (rc < 0)
595 			return rc;
596 
597 		return 1;
598 	}
599 
600 	return 0;
601 }
602 
603 /* Try to find the IRQ the TPM is using. This is for legacy x86 systems that
604  * do not have ACPI/etc. We typically expect the interrupt to be declared if
605  * present.
606  */
607 static void tpm_tis_probe_irq(struct tpm_chip *chip, u32 intmask)
608 {
609 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
610 	u8 original_int_vec;
611 	int i, rc;
612 
613 	rc = tpm_tis_read8(priv, TPM_INT_VECTOR(priv->locality),
614 			   &original_int_vec);
615 	if (rc < 0)
616 		return;
617 
618 	if (!original_int_vec) {
619 		if (IS_ENABLED(CONFIG_X86))
620 			for (i = 3; i <= 15; i++)
621 				if (!tpm_tis_probe_irq_single(chip, intmask, 0,
622 							      i))
623 					return;
624 	} else if (!tpm_tis_probe_irq_single(chip, intmask, 0,
625 					     original_int_vec))
626 		return;
627 }
628 
629 void tpm_tis_remove(struct tpm_chip *chip)
630 {
631 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
632 	u32 reg = TPM_INT_ENABLE(priv->locality);
633 	u32 interrupt;
634 	int rc;
635 
636 	rc = tpm_tis_read32(priv, reg, &interrupt);
637 	if (rc < 0)
638 		interrupt = 0;
639 
640 	tpm_tis_write32(priv, reg, ~TPM_GLOBAL_INT_ENABLE & interrupt);
641 	release_locality(chip, priv->locality, 1);
642 }
643 EXPORT_SYMBOL_GPL(tpm_tis_remove);
644 
645 static const struct tpm_class_ops tpm_tis = {
646 	.status = tpm_tis_status,
647 	.recv = tpm_tis_recv,
648 	.send = tpm_tis_send,
649 	.cancel = tpm_tis_ready,
650 	.update_timeouts = tpm_tis_update_timeouts,
651 	.req_complete_mask = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
652 	.req_complete_val = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
653 	.req_canceled = tpm_tis_req_canceled,
654 };
655 
656 int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
657 		      const struct tpm_tis_phy_ops *phy_ops,
658 		      acpi_handle acpi_dev_handle)
659 {
660 	u32 vendor, intfcaps, intmask;
661 	u8 rid;
662 	int rc, probe;
663 	struct tpm_chip *chip;
664 
665 	chip = tpmm_chip_alloc(dev, &tpm_tis);
666 	if (IS_ERR(chip))
667 		return PTR_ERR(chip);
668 
669 #ifdef CONFIG_ACPI
670 	chip->acpi_dev_handle = acpi_dev_handle;
671 #endif
672 
673 	/* Maximum timeouts */
674 	chip->timeout_a = TIS_TIMEOUT_A_MAX;
675 	chip->timeout_b = TIS_TIMEOUT_B_MAX;
676 	chip->timeout_c = TIS_TIMEOUT_C_MAX;
677 	chip->timeout_d = TIS_TIMEOUT_D_MAX;
678 	priv->phy_ops = phy_ops;
679 	dev_set_drvdata(&chip->dev, priv);
680 
681 	if (wait_startup(chip, 0) != 0) {
682 		rc = -ENODEV;
683 		goto out_err;
684 	}
685 
686 	/* Take control of the TPM's interrupt hardware and shut it off */
687 	rc = tpm_tis_read32(priv, TPM_INT_ENABLE(priv->locality), &intmask);
688 	if (rc < 0)
689 		goto out_err;
690 
691 	intmask |= TPM_INTF_CMD_READY_INT | TPM_INTF_LOCALITY_CHANGE_INT |
692 		   TPM_INTF_DATA_AVAIL_INT | TPM_INTF_STS_VALID_INT;
693 	intmask &= ~TPM_GLOBAL_INT_ENABLE;
694 	tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality), intmask);
695 
696 	if (request_locality(chip, 0) != 0) {
697 		rc = -ENODEV;
698 		goto out_err;
699 	}
700 
701 	rc = tpm2_probe(chip);
702 	if (rc)
703 		goto out_err;
704 
705 	rc = tpm_tis_read32(priv, TPM_DID_VID(0), &vendor);
706 	if (rc < 0)
707 		goto out_err;
708 
709 	priv->manufacturer_id = vendor;
710 
711 	rc = tpm_tis_read8(priv, TPM_RID(0), &rid);
712 	if (rc < 0)
713 		goto out_err;
714 
715 	dev_info(dev, "%s TPM (device-id 0x%X, rev-id %d)\n",
716 		 (chip->flags & TPM_CHIP_FLAG_TPM2) ? "2.0" : "1.2",
717 		 vendor >> 16, rid);
718 
719 	if (!(priv->flags & TPM_TIS_ITPM_POSSIBLE)) {
720 		probe = probe_itpm(chip);
721 		if (probe < 0) {
722 			rc = -ENODEV;
723 			goto out_err;
724 		}
725 
726 		if (!!probe)
727 			priv->flags |= TPM_TIS_ITPM_POSSIBLE;
728 	}
729 
730 	/* Figure out the capabilities */
731 	rc = tpm_tis_read32(priv, TPM_INTF_CAPS(priv->locality), &intfcaps);
732 	if (rc < 0)
733 		goto out_err;
734 
735 	dev_dbg(dev, "TPM interface capabilities (0x%x):\n",
736 		intfcaps);
737 	if (intfcaps & TPM_INTF_BURST_COUNT_STATIC)
738 		dev_dbg(dev, "\tBurst Count Static\n");
739 	if (intfcaps & TPM_INTF_CMD_READY_INT)
740 		dev_dbg(dev, "\tCommand Ready Int Support\n");
741 	if (intfcaps & TPM_INTF_INT_EDGE_FALLING)
742 		dev_dbg(dev, "\tInterrupt Edge Falling\n");
743 	if (intfcaps & TPM_INTF_INT_EDGE_RISING)
744 		dev_dbg(dev, "\tInterrupt Edge Rising\n");
745 	if (intfcaps & TPM_INTF_INT_LEVEL_LOW)
746 		dev_dbg(dev, "\tInterrupt Level Low\n");
747 	if (intfcaps & TPM_INTF_INT_LEVEL_HIGH)
748 		dev_dbg(dev, "\tInterrupt Level High\n");
749 	if (intfcaps & TPM_INTF_LOCALITY_CHANGE_INT)
750 		dev_dbg(dev, "\tLocality Change Int Support\n");
751 	if (intfcaps & TPM_INTF_STS_VALID_INT)
752 		dev_dbg(dev, "\tSts Valid Int Support\n");
753 	if (intfcaps & TPM_INTF_DATA_AVAIL_INT)
754 		dev_dbg(dev, "\tData Avail Int Support\n");
755 
756 	/* Very early on issue a command to the TPM in polling mode to make
757 	 * sure it works. May as well use that command to set the proper
758 	 *  timeouts for the driver.
759 	 */
760 	if (tpm_get_timeouts(chip)) {
761 		dev_err(dev, "Could not get TPM timeouts and durations\n");
762 		rc = -ENODEV;
763 		goto out_err;
764 	}
765 
766 	/* INTERRUPT Setup */
767 	init_waitqueue_head(&priv->read_queue);
768 	init_waitqueue_head(&priv->int_queue);
769 	if (irq != -1) {
770 		if (irq) {
771 			tpm_tis_probe_irq_single(chip, intmask, IRQF_SHARED,
772 						 irq);
773 			if (!(chip->flags & TPM_CHIP_FLAG_IRQ))
774 				dev_err(&chip->dev, FW_BUG
775 					"TPM interrupt not working, polling instead\n");
776 		} else {
777 			tpm_tis_probe_irq(chip, intmask);
778 		}
779 	}
780 
781 	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
782 		rc = tpm2_do_selftest(chip);
783 		if (rc == TPM2_RC_INITIALIZE) {
784 			dev_warn(dev, "Firmware has not started TPM\n");
785 			rc  = tpm2_startup(chip, TPM2_SU_CLEAR);
786 			if (!rc)
787 				rc = tpm2_do_selftest(chip);
788 		}
789 
790 		if (rc) {
791 			dev_err(dev, "TPM self test failed\n");
792 			if (rc > 0)
793 				rc = -ENODEV;
794 			goto out_err;
795 		}
796 	} else {
797 		if (tpm_do_selftest(chip)) {
798 			dev_err(dev, "TPM self test failed\n");
799 			rc = -ENODEV;
800 			goto out_err;
801 		}
802 	}
803 
804 	return tpm_chip_register(chip);
805 out_err:
806 	tpm_tis_remove(chip);
807 	return rc;
808 }
809 EXPORT_SYMBOL_GPL(tpm_tis_core_init);
810 
811 #ifdef CONFIG_PM_SLEEP
812 static void tpm_tis_reenable_interrupts(struct tpm_chip *chip)
813 {
814 	struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
815 	u32 intmask;
816 	int rc;
817 
818 	/* reenable interrupts that device may have lost or
819 	 * BIOS/firmware may have disabled
820 	 */
821 	rc = tpm_tis_write8(priv, TPM_INT_VECTOR(priv->locality), priv->irq);
822 	if (rc < 0)
823 		return;
824 
825 	rc = tpm_tis_read32(priv, TPM_INT_ENABLE(priv->locality), &intmask);
826 	if (rc < 0)
827 		return;
828 
829 	intmask |= TPM_INTF_CMD_READY_INT
830 	    | TPM_INTF_LOCALITY_CHANGE_INT | TPM_INTF_DATA_AVAIL_INT
831 	    | TPM_INTF_STS_VALID_INT | TPM_GLOBAL_INT_ENABLE;
832 
833 	tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality), intmask);
834 }
835 
836 int tpm_tis_resume(struct device *dev)
837 {
838 	struct tpm_chip *chip = dev_get_drvdata(dev);
839 	int ret;
840 
841 	if (chip->flags & TPM_CHIP_FLAG_IRQ)
842 		tpm_tis_reenable_interrupts(chip);
843 
844 	ret = tpm_pm_resume(dev);
845 	if (ret)
846 		return ret;
847 
848 	/* TPM 1.2 requires self-test on resume. This function actually returns
849 	 * an error code but for unknown reason it isn't handled.
850 	 */
851 	if (!(chip->flags & TPM_CHIP_FLAG_TPM2))
852 		tpm_do_selftest(chip);
853 
854 	return 0;
855 }
856 EXPORT_SYMBOL_GPL(tpm_tis_resume);
857 #endif
858 
859 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
860 MODULE_DESCRIPTION("TPM Driver");
861 MODULE_VERSION("2.0");
862 MODULE_LICENSE("GPL");
863