xref: /openbmc/linux/drivers/char/tpm/tpm_tis.c (revision 3d9b448b)
1 /*
2  * Copyright (C) 2005, 2006 IBM Corporation
3  * Copyright (C) 2014 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 
33 enum tis_access {
34 	TPM_ACCESS_VALID = 0x80,
35 	TPM_ACCESS_ACTIVE_LOCALITY = 0x20,
36 	TPM_ACCESS_REQUEST_PENDING = 0x04,
37 	TPM_ACCESS_REQUEST_USE = 0x02,
38 };
39 
40 enum tis_status {
41 	TPM_STS_VALID = 0x80,
42 	TPM_STS_COMMAND_READY = 0x40,
43 	TPM_STS_GO = 0x20,
44 	TPM_STS_DATA_AVAIL = 0x10,
45 	TPM_STS_DATA_EXPECT = 0x08,
46 };
47 
48 enum tis_int_flags {
49 	TPM_GLOBAL_INT_ENABLE = 0x80000000,
50 	TPM_INTF_BURST_COUNT_STATIC = 0x100,
51 	TPM_INTF_CMD_READY_INT = 0x080,
52 	TPM_INTF_INT_EDGE_FALLING = 0x040,
53 	TPM_INTF_INT_EDGE_RISING = 0x020,
54 	TPM_INTF_INT_LEVEL_LOW = 0x010,
55 	TPM_INTF_INT_LEVEL_HIGH = 0x008,
56 	TPM_INTF_LOCALITY_CHANGE_INT = 0x004,
57 	TPM_INTF_STS_VALID_INT = 0x002,
58 	TPM_INTF_DATA_AVAIL_INT = 0x001,
59 };
60 
61 enum tis_defaults {
62 	TIS_MEM_BASE = 0xFED40000,
63 	TIS_MEM_LEN = 0x5000,
64 	TIS_SHORT_TIMEOUT = 750,	/* ms */
65 	TIS_LONG_TIMEOUT = 2000,	/* 2 sec */
66 };
67 
68 
69 /* Some timeout values are needed before it is known whether the chip is
70  * TPM 1.0 or TPM 2.0.
71  */
72 #define TIS_TIMEOUT_A_MAX	max(TIS_SHORT_TIMEOUT, TPM2_TIMEOUT_A)
73 #define TIS_TIMEOUT_B_MAX	max(TIS_LONG_TIMEOUT, TPM2_TIMEOUT_B)
74 #define TIS_TIMEOUT_C_MAX	max(TIS_SHORT_TIMEOUT, TPM2_TIMEOUT_C)
75 #define TIS_TIMEOUT_D_MAX	max(TIS_SHORT_TIMEOUT, TPM2_TIMEOUT_D)
76 
77 #define	TPM_ACCESS(l)			(0x0000 | ((l) << 12))
78 #define	TPM_INT_ENABLE(l)		(0x0008 | ((l) << 12))
79 #define	TPM_INT_VECTOR(l)		(0x000C | ((l) << 12))
80 #define	TPM_INT_STATUS(l)		(0x0010 | ((l) << 12))
81 #define	TPM_INTF_CAPS(l)		(0x0014 | ((l) << 12))
82 #define	TPM_STS(l)			(0x0018 | ((l) << 12))
83 #define	TPM_STS3(l)			(0x001b | ((l) << 12))
84 #define	TPM_DATA_FIFO(l)		(0x0024 | ((l) << 12))
85 
86 #define	TPM_DID_VID(l)			(0x0F00 | ((l) << 12))
87 #define	TPM_RID(l)			(0x0F04 | ((l) << 12))
88 
89 struct priv_data {
90 	bool irq_tested;
91 };
92 
93 #if defined(CONFIG_PNP) && defined(CONFIG_ACPI)
94 static int is_itpm(struct pnp_dev *dev)
95 {
96 	struct acpi_device *acpi = pnp_acpi_device(dev);
97 	struct acpi_hardware_id *id;
98 
99 	if (!acpi)
100 		return 0;
101 
102 	list_for_each_entry(id, &acpi->pnp.ids, list) {
103 		if (!strcmp("INTC0102", id->id))
104 			return 1;
105 	}
106 
107 	return 0;
108 }
109 #else
110 static inline int is_itpm(struct pnp_dev *dev)
111 {
112 	return 0;
113 }
114 #endif
115 
116 /* Before we attempt to access the TPM we must see that the valid bit is set.
117  * The specification says that this bit is 0 at reset and remains 0 until the
118  * 'TPM has gone through its self test and initialization and has established
119  * correct values in the other bits.' */
120 static int wait_startup(struct tpm_chip *chip, int l)
121 {
122 	unsigned long stop = jiffies + chip->vendor.timeout_a;
123 	do {
124 		if (ioread8(chip->vendor.iobase + TPM_ACCESS(l)) &
125 		    TPM_ACCESS_VALID)
126 			return 0;
127 		msleep(TPM_TIMEOUT);
128 	} while (time_before(jiffies, stop));
129 	return -1;
130 }
131 
132 static int check_locality(struct tpm_chip *chip, int l)
133 {
134 	if ((ioread8(chip->vendor.iobase + TPM_ACCESS(l)) &
135 	     (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) ==
136 	    (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID))
137 		return chip->vendor.locality = l;
138 
139 	return -1;
140 }
141 
142 static void release_locality(struct tpm_chip *chip, int l, int force)
143 {
144 	if (force || (ioread8(chip->vendor.iobase + TPM_ACCESS(l)) &
145 		      (TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID)) ==
146 	    (TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID))
147 		iowrite8(TPM_ACCESS_ACTIVE_LOCALITY,
148 			 chip->vendor.iobase + TPM_ACCESS(l));
149 }
150 
151 static int request_locality(struct tpm_chip *chip, int l)
152 {
153 	unsigned long stop, timeout;
154 	long rc;
155 
156 	if (check_locality(chip, l) >= 0)
157 		return l;
158 
159 	iowrite8(TPM_ACCESS_REQUEST_USE,
160 		 chip->vendor.iobase + TPM_ACCESS(l));
161 
162 	stop = jiffies + chip->vendor.timeout_a;
163 
164 	if (chip->vendor.irq) {
165 again:
166 		timeout = stop - jiffies;
167 		if ((long)timeout <= 0)
168 			return -1;
169 		rc = wait_event_interruptible_timeout(chip->vendor.int_queue,
170 						      (check_locality
171 						       (chip, l) >= 0),
172 						      timeout);
173 		if (rc > 0)
174 			return l;
175 		if (rc == -ERESTARTSYS && freezing(current)) {
176 			clear_thread_flag(TIF_SIGPENDING);
177 			goto again;
178 		}
179 	} else {
180 		/* wait for burstcount */
181 		do {
182 			if (check_locality(chip, l) >= 0)
183 				return l;
184 			msleep(TPM_TIMEOUT);
185 		}
186 		while (time_before(jiffies, stop));
187 	}
188 	return -1;
189 }
190 
191 static u8 tpm_tis_status(struct tpm_chip *chip)
192 {
193 	return ioread8(chip->vendor.iobase +
194 		       TPM_STS(chip->vendor.locality));
195 }
196 
197 static void tpm_tis_ready(struct tpm_chip *chip)
198 {
199 	/* this causes the current command to be aborted */
200 	iowrite8(TPM_STS_COMMAND_READY,
201 		 chip->vendor.iobase + TPM_STS(chip->vendor.locality));
202 }
203 
204 static int get_burstcount(struct tpm_chip *chip)
205 {
206 	unsigned long stop;
207 	int burstcnt;
208 
209 	/* wait for burstcount */
210 	/* which timeout value, spec has 2 answers (c & d) */
211 	stop = jiffies + chip->vendor.timeout_d;
212 	do {
213 		burstcnt = ioread8(chip->vendor.iobase +
214 				   TPM_STS(chip->vendor.locality) + 1);
215 		burstcnt += ioread8(chip->vendor.iobase +
216 				    TPM_STS(chip->vendor.locality) +
217 				    2) << 8;
218 		if (burstcnt)
219 			return burstcnt;
220 		msleep(TPM_TIMEOUT);
221 	} while (time_before(jiffies, stop));
222 	return -EBUSY;
223 }
224 
225 static int recv_data(struct tpm_chip *chip, u8 *buf, size_t count)
226 {
227 	int size = 0, burstcnt;
228 	while (size < count &&
229 	       wait_for_tpm_stat(chip,
230 				 TPM_STS_DATA_AVAIL | TPM_STS_VALID,
231 				 chip->vendor.timeout_c,
232 				 &chip->vendor.read_queue, true)
233 	       == 0) {
234 		burstcnt = get_burstcount(chip);
235 		for (; burstcnt > 0 && size < count; burstcnt--)
236 			buf[size++] = ioread8(chip->vendor.iobase +
237 					      TPM_DATA_FIFO(chip->vendor.
238 							    locality));
239 	}
240 	return size;
241 }
242 
243 static int tpm_tis_recv(struct tpm_chip *chip, u8 *buf, size_t count)
244 {
245 	int size = 0;
246 	int expected, status;
247 
248 	if (count < TPM_HEADER_SIZE) {
249 		size = -EIO;
250 		goto out;
251 	}
252 
253 	/* read first 10 bytes, including tag, paramsize, and result */
254 	if ((size =
255 	     recv_data(chip, buf, TPM_HEADER_SIZE)) < TPM_HEADER_SIZE) {
256 		dev_err(chip->pdev, "Unable to read header\n");
257 		goto out;
258 	}
259 
260 	expected = be32_to_cpu(*(__be32 *) (buf + 2));
261 	if (expected > count) {
262 		size = -EIO;
263 		goto out;
264 	}
265 
266 	if ((size +=
267 	     recv_data(chip, &buf[TPM_HEADER_SIZE],
268 		       expected - TPM_HEADER_SIZE)) < expected) {
269 		dev_err(chip->pdev, "Unable to read remainder of result\n");
270 		size = -ETIME;
271 		goto out;
272 	}
273 
274 	wait_for_tpm_stat(chip, TPM_STS_VALID, chip->vendor.timeout_c,
275 			  &chip->vendor.int_queue, false);
276 	status = tpm_tis_status(chip);
277 	if (status & TPM_STS_DATA_AVAIL) {	/* retry? */
278 		dev_err(chip->pdev, "Error left over data\n");
279 		size = -EIO;
280 		goto out;
281 	}
282 
283 out:
284 	tpm_tis_ready(chip);
285 	release_locality(chip, chip->vendor.locality, 0);
286 	return size;
287 }
288 
289 static bool itpm;
290 module_param(itpm, bool, 0444);
291 MODULE_PARM_DESC(itpm, "Force iTPM workarounds (found on some Lenovo laptops)");
292 
293 /*
294  * If interrupts are used (signaled by an irq set in the vendor structure)
295  * tpm.c can skip polling for the data to be available as the interrupt is
296  * waited for here
297  */
298 static int tpm_tis_send_data(struct tpm_chip *chip, u8 *buf, size_t len)
299 {
300 	int rc, status, burstcnt;
301 	size_t count = 0;
302 
303 	if (request_locality(chip, 0) < 0)
304 		return -EBUSY;
305 
306 	status = tpm_tis_status(chip);
307 	if ((status & TPM_STS_COMMAND_READY) == 0) {
308 		tpm_tis_ready(chip);
309 		if (wait_for_tpm_stat
310 		    (chip, TPM_STS_COMMAND_READY, chip->vendor.timeout_b,
311 		     &chip->vendor.int_queue, false) < 0) {
312 			rc = -ETIME;
313 			goto out_err;
314 		}
315 	}
316 
317 	while (count < len - 1) {
318 		burstcnt = get_burstcount(chip);
319 		for (; burstcnt > 0 && count < len - 1; burstcnt--) {
320 			iowrite8(buf[count], chip->vendor.iobase +
321 				 TPM_DATA_FIFO(chip->vendor.locality));
322 			count++;
323 		}
324 
325 		wait_for_tpm_stat(chip, TPM_STS_VALID, chip->vendor.timeout_c,
326 				  &chip->vendor.int_queue, false);
327 		status = tpm_tis_status(chip);
328 		if (!itpm && (status & TPM_STS_DATA_EXPECT) == 0) {
329 			rc = -EIO;
330 			goto out_err;
331 		}
332 	}
333 
334 	/* write last byte */
335 	iowrite8(buf[count],
336 		 chip->vendor.iobase + TPM_DATA_FIFO(chip->vendor.locality));
337 	wait_for_tpm_stat(chip, TPM_STS_VALID, chip->vendor.timeout_c,
338 			  &chip->vendor.int_queue, false);
339 	status = tpm_tis_status(chip);
340 	if ((status & TPM_STS_DATA_EXPECT) != 0) {
341 		rc = -EIO;
342 		goto out_err;
343 	}
344 
345 	return 0;
346 
347 out_err:
348 	tpm_tis_ready(chip);
349 	release_locality(chip, chip->vendor.locality, 0);
350 	return rc;
351 }
352 
353 static void disable_interrupts(struct tpm_chip *chip)
354 {
355 	u32 intmask;
356 
357 	intmask =
358 	    ioread32(chip->vendor.iobase +
359 		     TPM_INT_ENABLE(chip->vendor.locality));
360 	intmask &= ~TPM_GLOBAL_INT_ENABLE;
361 	iowrite32(intmask,
362 		  chip->vendor.iobase +
363 		  TPM_INT_ENABLE(chip->vendor.locality));
364 	free_irq(chip->vendor.irq, chip);
365 	chip->vendor.irq = 0;
366 }
367 
368 /*
369  * If interrupts are used (signaled by an irq set in the vendor structure)
370  * tpm.c can skip polling for the data to be available as the interrupt is
371  * waited for here
372  */
373 static int tpm_tis_send_main(struct tpm_chip *chip, u8 *buf, size_t len)
374 {
375 	int rc;
376 	u32 ordinal;
377 	unsigned long dur;
378 
379 	rc = tpm_tis_send_data(chip, buf, len);
380 	if (rc < 0)
381 		return rc;
382 
383 	/* go and do it */
384 	iowrite8(TPM_STS_GO,
385 		 chip->vendor.iobase + TPM_STS(chip->vendor.locality));
386 
387 	if (chip->vendor.irq) {
388 		ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
389 
390 		if (chip->flags & TPM_CHIP_FLAG_TPM2)
391 			dur = tpm2_calc_ordinal_duration(chip, ordinal);
392 		else
393 			dur = tpm_calc_ordinal_duration(chip, ordinal);
394 
395 		if (wait_for_tpm_stat
396 		    (chip, TPM_STS_DATA_AVAIL | TPM_STS_VALID, dur,
397 		     &chip->vendor.read_queue, false) < 0) {
398 			rc = -ETIME;
399 			goto out_err;
400 		}
401 	}
402 	return len;
403 out_err:
404 	tpm_tis_ready(chip);
405 	release_locality(chip, chip->vendor.locality, 0);
406 	return rc;
407 }
408 
409 static int tpm_tis_send(struct tpm_chip *chip, u8 *buf, size_t len)
410 {
411 	int rc, irq;
412 	struct priv_data *priv = chip->vendor.priv;
413 
414 	if (!chip->vendor.irq || priv->irq_tested)
415 		return tpm_tis_send_main(chip, buf, len);
416 
417 	/* Verify receipt of the expected IRQ */
418 	irq = chip->vendor.irq;
419 	chip->vendor.irq = 0;
420 	rc = tpm_tis_send_main(chip, buf, len);
421 	chip->vendor.irq = irq;
422 	if (!priv->irq_tested)
423 		msleep(1);
424 	if (!priv->irq_tested) {
425 		disable_interrupts(chip);
426 		dev_err(chip->pdev,
427 			FW_BUG "TPM interrupt not working, polling instead\n");
428 	}
429 	priv->irq_tested = true;
430 	return rc;
431 }
432 
433 struct tis_vendor_timeout_override {
434 	u32 did_vid;
435 	unsigned long timeout_us[4];
436 };
437 
438 static const struct tis_vendor_timeout_override vendor_timeout_overrides[] = {
439 	/* Atmel 3204 */
440 	{ 0x32041114, { (TIS_SHORT_TIMEOUT*1000), (TIS_LONG_TIMEOUT*1000),
441 			(TIS_SHORT_TIMEOUT*1000), (TIS_SHORT_TIMEOUT*1000) } },
442 };
443 
444 static bool tpm_tis_update_timeouts(struct tpm_chip *chip,
445 				    unsigned long *timeout_cap)
446 {
447 	int i;
448 	u32 did_vid;
449 
450 	did_vid = ioread32(chip->vendor.iobase + TPM_DID_VID(0));
451 
452 	for (i = 0; i != ARRAY_SIZE(vendor_timeout_overrides); i++) {
453 		if (vendor_timeout_overrides[i].did_vid != did_vid)
454 			continue;
455 		memcpy(timeout_cap, vendor_timeout_overrides[i].timeout_us,
456 		       sizeof(vendor_timeout_overrides[i].timeout_us));
457 		return true;
458 	}
459 
460 	return false;
461 }
462 
463 /*
464  * Early probing for iTPM with STS_DATA_EXPECT flaw.
465  * Try sending command without itpm flag set and if that
466  * fails, repeat with itpm flag set.
467  */
468 static int probe_itpm(struct tpm_chip *chip)
469 {
470 	int rc = 0;
471 	u8 cmd_getticks[] = {
472 		0x00, 0xc1, 0x00, 0x00, 0x00, 0x0a,
473 		0x00, 0x00, 0x00, 0xf1
474 	};
475 	size_t len = sizeof(cmd_getticks);
476 	bool rem_itpm = itpm;
477 	u16 vendor = ioread16(chip->vendor.iobase + TPM_DID_VID(0));
478 
479 	/* probe only iTPMS */
480 	if (vendor != TPM_VID_INTEL)
481 		return 0;
482 
483 	itpm = false;
484 
485 	rc = tpm_tis_send_data(chip, cmd_getticks, len);
486 	if (rc == 0)
487 		goto out;
488 
489 	tpm_tis_ready(chip);
490 	release_locality(chip, chip->vendor.locality, 0);
491 
492 	itpm = true;
493 
494 	rc = tpm_tis_send_data(chip, cmd_getticks, len);
495 	if (rc == 0) {
496 		dev_info(chip->pdev, "Detected an iTPM.\n");
497 		rc = 1;
498 	} else
499 		rc = -EFAULT;
500 
501 out:
502 	itpm = rem_itpm;
503 	tpm_tis_ready(chip);
504 	release_locality(chip, chip->vendor.locality, 0);
505 
506 	return rc;
507 }
508 
509 static bool tpm_tis_req_canceled(struct tpm_chip *chip, u8 status)
510 {
511 	switch (chip->vendor.manufacturer_id) {
512 	case TPM_VID_WINBOND:
513 		return ((status == TPM_STS_VALID) ||
514 			(status == (TPM_STS_VALID | TPM_STS_COMMAND_READY)));
515 	case TPM_VID_STM:
516 		return (status == (TPM_STS_VALID | TPM_STS_COMMAND_READY));
517 	default:
518 		return (status == TPM_STS_COMMAND_READY);
519 	}
520 }
521 
522 static const struct tpm_class_ops tpm_tis = {
523 	.status = tpm_tis_status,
524 	.recv = tpm_tis_recv,
525 	.send = tpm_tis_send,
526 	.cancel = tpm_tis_ready,
527 	.update_timeouts = tpm_tis_update_timeouts,
528 	.req_complete_mask = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
529 	.req_complete_val = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
530 	.req_canceled = tpm_tis_req_canceled,
531 };
532 
533 static irqreturn_t tis_int_probe(int irq, void *dev_id)
534 {
535 	struct tpm_chip *chip = dev_id;
536 	u32 interrupt;
537 
538 	interrupt = ioread32(chip->vendor.iobase +
539 			     TPM_INT_STATUS(chip->vendor.locality));
540 
541 	if (interrupt == 0)
542 		return IRQ_NONE;
543 
544 	chip->vendor.probed_irq = irq;
545 
546 	/* Clear interrupts handled with TPM_EOI */
547 	iowrite32(interrupt,
548 		  chip->vendor.iobase +
549 		  TPM_INT_STATUS(chip->vendor.locality));
550 	return IRQ_HANDLED;
551 }
552 
553 static irqreturn_t tis_int_handler(int dummy, void *dev_id)
554 {
555 	struct tpm_chip *chip = dev_id;
556 	u32 interrupt;
557 	int i;
558 
559 	interrupt = ioread32(chip->vendor.iobase +
560 			     TPM_INT_STATUS(chip->vendor.locality));
561 
562 	if (interrupt == 0)
563 		return IRQ_NONE;
564 
565 	((struct priv_data *)chip->vendor.priv)->irq_tested = true;
566 	if (interrupt & TPM_INTF_DATA_AVAIL_INT)
567 		wake_up_interruptible(&chip->vendor.read_queue);
568 	if (interrupt & TPM_INTF_LOCALITY_CHANGE_INT)
569 		for (i = 0; i < 5; i++)
570 			if (check_locality(chip, i) >= 0)
571 				break;
572 	if (interrupt &
573 	    (TPM_INTF_LOCALITY_CHANGE_INT | TPM_INTF_STS_VALID_INT |
574 	     TPM_INTF_CMD_READY_INT))
575 		wake_up_interruptible(&chip->vendor.int_queue);
576 
577 	/* Clear interrupts handled with TPM_EOI */
578 	iowrite32(interrupt,
579 		  chip->vendor.iobase +
580 		  TPM_INT_STATUS(chip->vendor.locality));
581 	ioread32(chip->vendor.iobase + TPM_INT_STATUS(chip->vendor.locality));
582 	return IRQ_HANDLED;
583 }
584 
585 static bool interrupts = true;
586 module_param(interrupts, bool, 0444);
587 MODULE_PARM_DESC(interrupts, "Enable interrupts");
588 
589 static void tpm_tis_remove(struct tpm_chip *chip)
590 {
591 	if (chip->flags & TPM_CHIP_FLAG_TPM2)
592 		tpm2_shutdown(chip, TPM2_SU_CLEAR);
593 
594 	iowrite32(~TPM_GLOBAL_INT_ENABLE &
595 		  ioread32(chip->vendor.iobase +
596 			   TPM_INT_ENABLE(chip->vendor.
597 					  locality)),
598 		  chip->vendor.iobase +
599 		  TPM_INT_ENABLE(chip->vendor.locality));
600 	release_locality(chip, chip->vendor.locality, 1);
601 }
602 
603 static int tpm_tis_init(struct device *dev, acpi_handle acpi_dev_handle,
604 			resource_size_t start, resource_size_t len,
605 			unsigned int irq)
606 {
607 	u32 vendor, intfcaps, intmask;
608 	int rc, i, irq_s, irq_e, probe;
609 	struct tpm_chip *chip;
610 	struct priv_data *priv;
611 
612 	priv = devm_kzalloc(dev, sizeof(struct priv_data), GFP_KERNEL);
613 	if (priv == NULL)
614 		return -ENOMEM;
615 
616 	chip = tpmm_chip_alloc(dev, &tpm_tis);
617 	if (IS_ERR(chip))
618 		return PTR_ERR(chip);
619 
620 	chip->vendor.priv = priv;
621 #ifdef CONFIG_ACPI
622 	chip->acpi_dev_handle = acpi_dev_handle;
623 #endif
624 
625 	chip->vendor.iobase = devm_ioremap(dev, start, len);
626 	if (!chip->vendor.iobase)
627 		return -EIO;
628 
629 	/* Maximum timeouts */
630 	chip->vendor.timeout_a = TIS_TIMEOUT_A_MAX;
631 	chip->vendor.timeout_b = TIS_TIMEOUT_B_MAX;
632 	chip->vendor.timeout_c = TIS_TIMEOUT_C_MAX;
633 	chip->vendor.timeout_d = TIS_TIMEOUT_D_MAX;
634 
635 	if (wait_startup(chip, 0) != 0) {
636 		rc = -ENODEV;
637 		goto out_err;
638 	}
639 
640 	if (request_locality(chip, 0) != 0) {
641 		rc = -ENODEV;
642 		goto out_err;
643 	}
644 
645 	rc = tpm2_probe(chip);
646 	if (rc)
647 		goto out_err;
648 
649 	vendor = ioread32(chip->vendor.iobase + TPM_DID_VID(0));
650 	chip->vendor.manufacturer_id = vendor;
651 
652 	dev_info(dev, "%s TPM (device-id 0x%X, rev-id %d)\n",
653 		 (chip->flags & TPM_CHIP_FLAG_TPM2) ? "2.0" : "1.2",
654 		 vendor >> 16, ioread8(chip->vendor.iobase + TPM_RID(0)));
655 
656 	if (!itpm) {
657 		probe = probe_itpm(chip);
658 		if (probe < 0) {
659 			rc = -ENODEV;
660 			goto out_err;
661 		}
662 		itpm = !!probe;
663 	}
664 
665 	if (itpm)
666 		dev_info(dev, "Intel iTPM workaround enabled\n");
667 
668 
669 	/* Figure out the capabilities */
670 	intfcaps =
671 	    ioread32(chip->vendor.iobase +
672 		     TPM_INTF_CAPS(chip->vendor.locality));
673 	dev_dbg(dev, "TPM interface capabilities (0x%x):\n",
674 		intfcaps);
675 	if (intfcaps & TPM_INTF_BURST_COUNT_STATIC)
676 		dev_dbg(dev, "\tBurst Count Static\n");
677 	if (intfcaps & TPM_INTF_CMD_READY_INT)
678 		dev_dbg(dev, "\tCommand Ready Int Support\n");
679 	if (intfcaps & TPM_INTF_INT_EDGE_FALLING)
680 		dev_dbg(dev, "\tInterrupt Edge Falling\n");
681 	if (intfcaps & TPM_INTF_INT_EDGE_RISING)
682 		dev_dbg(dev, "\tInterrupt Edge Rising\n");
683 	if (intfcaps & TPM_INTF_INT_LEVEL_LOW)
684 		dev_dbg(dev, "\tInterrupt Level Low\n");
685 	if (intfcaps & TPM_INTF_INT_LEVEL_HIGH)
686 		dev_dbg(dev, "\tInterrupt Level High\n");
687 	if (intfcaps & TPM_INTF_LOCALITY_CHANGE_INT)
688 		dev_dbg(dev, "\tLocality Change Int Support\n");
689 	if (intfcaps & TPM_INTF_STS_VALID_INT)
690 		dev_dbg(dev, "\tSts Valid Int Support\n");
691 	if (intfcaps & TPM_INTF_DATA_AVAIL_INT)
692 		dev_dbg(dev, "\tData Avail Int Support\n");
693 
694 	/* INTERRUPT Setup */
695 	init_waitqueue_head(&chip->vendor.read_queue);
696 	init_waitqueue_head(&chip->vendor.int_queue);
697 
698 	intmask =
699 	    ioread32(chip->vendor.iobase +
700 		     TPM_INT_ENABLE(chip->vendor.locality));
701 
702 	intmask |= TPM_INTF_CMD_READY_INT
703 	    | TPM_INTF_LOCALITY_CHANGE_INT | TPM_INTF_DATA_AVAIL_INT
704 	    | TPM_INTF_STS_VALID_INT;
705 
706 	iowrite32(intmask,
707 		  chip->vendor.iobase +
708 		  TPM_INT_ENABLE(chip->vendor.locality));
709 	if (interrupts)
710 		chip->vendor.irq = irq;
711 	if (interrupts && !chip->vendor.irq) {
712 		irq_s =
713 		    ioread8(chip->vendor.iobase +
714 			    TPM_INT_VECTOR(chip->vendor.locality));
715 		if (irq_s) {
716 			irq_e = irq_s;
717 		} else {
718 			irq_s = 3;
719 			irq_e = 15;
720 		}
721 
722 		for (i = irq_s; i <= irq_e && chip->vendor.irq == 0; i++) {
723 			iowrite8(i, chip->vendor.iobase +
724 				 TPM_INT_VECTOR(chip->vendor.locality));
725 			if (devm_request_irq
726 			    (dev, i, tis_int_probe, IRQF_SHARED,
727 			     chip->devname, chip) != 0) {
728 				dev_info(chip->pdev,
729 					 "Unable to request irq: %d for probe\n",
730 					 i);
731 				continue;
732 			}
733 
734 			/* Clear all existing */
735 			iowrite32(ioread32
736 				  (chip->vendor.iobase +
737 				   TPM_INT_STATUS(chip->vendor.locality)),
738 				  chip->vendor.iobase +
739 				  TPM_INT_STATUS(chip->vendor.locality));
740 
741 			/* Turn on */
742 			iowrite32(intmask | TPM_GLOBAL_INT_ENABLE,
743 				  chip->vendor.iobase +
744 				  TPM_INT_ENABLE(chip->vendor.locality));
745 
746 			chip->vendor.probed_irq = 0;
747 
748 			/* Generate Interrupts */
749 			if (chip->flags & TPM_CHIP_FLAG_TPM2)
750 				tpm2_gen_interrupt(chip);
751 			else
752 				tpm_gen_interrupt(chip);
753 
754 			chip->vendor.irq = chip->vendor.probed_irq;
755 
756 			/* free_irq will call into tis_int_probe;
757 			   clear all irqs we haven't seen while doing
758 			   tpm_gen_interrupt */
759 			iowrite32(ioread32
760 				  (chip->vendor.iobase +
761 				   TPM_INT_STATUS(chip->vendor.locality)),
762 				  chip->vendor.iobase +
763 				  TPM_INT_STATUS(chip->vendor.locality));
764 
765 			/* Turn off */
766 			iowrite32(intmask,
767 				  chip->vendor.iobase +
768 				  TPM_INT_ENABLE(chip->vendor.locality));
769 		}
770 	}
771 	if (chip->vendor.irq) {
772 		iowrite8(chip->vendor.irq,
773 			 chip->vendor.iobase +
774 			 TPM_INT_VECTOR(chip->vendor.locality));
775 		if (devm_request_irq
776 		    (dev, chip->vendor.irq, tis_int_handler, IRQF_SHARED,
777 		     chip->devname, chip) != 0) {
778 			dev_info(chip->pdev,
779 				 "Unable to request irq: %d for use\n",
780 				 chip->vendor.irq);
781 			chip->vendor.irq = 0;
782 		} else {
783 			/* Clear all existing */
784 			iowrite32(ioread32
785 				  (chip->vendor.iobase +
786 				   TPM_INT_STATUS(chip->vendor.locality)),
787 				  chip->vendor.iobase +
788 				  TPM_INT_STATUS(chip->vendor.locality));
789 
790 			/* Turn on */
791 			iowrite32(intmask | TPM_GLOBAL_INT_ENABLE,
792 				  chip->vendor.iobase +
793 				  TPM_INT_ENABLE(chip->vendor.locality));
794 		}
795 	}
796 
797 	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
798 		chip->vendor.timeout_a = msecs_to_jiffies(TPM2_TIMEOUT_A);
799 		chip->vendor.timeout_b = msecs_to_jiffies(TPM2_TIMEOUT_B);
800 		chip->vendor.timeout_c = msecs_to_jiffies(TPM2_TIMEOUT_C);
801 		chip->vendor.timeout_d = msecs_to_jiffies(TPM2_TIMEOUT_D);
802 		chip->vendor.duration[TPM_SHORT] =
803 			msecs_to_jiffies(TPM2_DURATION_SHORT);
804 		chip->vendor.duration[TPM_MEDIUM] =
805 			msecs_to_jiffies(TPM2_DURATION_MEDIUM);
806 		chip->vendor.duration[TPM_LONG] =
807 			msecs_to_jiffies(TPM2_DURATION_LONG);
808 
809 		rc = tpm2_do_selftest(chip);
810 		if (rc == TPM2_RC_INITIALIZE) {
811 			dev_warn(dev, "Firmware has not started TPM\n");
812 			rc  = tpm2_startup(chip, TPM2_SU_CLEAR);
813 			if (!rc)
814 				rc = tpm2_do_selftest(chip);
815 		}
816 
817 		if (rc) {
818 			dev_err(dev, "TPM self test failed\n");
819 			if (rc > 0)
820 				rc = -ENODEV;
821 			goto out_err;
822 		}
823 	} else {
824 		if (tpm_get_timeouts(chip)) {
825 			dev_err(dev, "Could not get TPM timeouts and durations\n");
826 			rc = -ENODEV;
827 			goto out_err;
828 		}
829 
830 		if (tpm_do_selftest(chip)) {
831 			dev_err(dev, "TPM self test failed\n");
832 			rc = -ENODEV;
833 			goto out_err;
834 		}
835 	}
836 
837 	return tpm_chip_register(chip);
838 out_err:
839 	tpm_tis_remove(chip);
840 	return rc;
841 }
842 
843 #ifdef CONFIG_PM_SLEEP
844 static void tpm_tis_reenable_interrupts(struct tpm_chip *chip)
845 {
846 	u32 intmask;
847 
848 	/* reenable interrupts that device may have lost or
849 	   BIOS/firmware may have disabled */
850 	iowrite8(chip->vendor.irq, chip->vendor.iobase +
851 		 TPM_INT_VECTOR(chip->vendor.locality));
852 
853 	intmask =
854 	    ioread32(chip->vendor.iobase +
855 		     TPM_INT_ENABLE(chip->vendor.locality));
856 
857 	intmask |= TPM_INTF_CMD_READY_INT
858 	    | TPM_INTF_LOCALITY_CHANGE_INT | TPM_INTF_DATA_AVAIL_INT
859 	    | TPM_INTF_STS_VALID_INT | TPM_GLOBAL_INT_ENABLE;
860 
861 	iowrite32(intmask,
862 		  chip->vendor.iobase + TPM_INT_ENABLE(chip->vendor.locality));
863 }
864 
865 static int tpm_tis_resume(struct device *dev)
866 {
867 	struct tpm_chip *chip = dev_get_drvdata(dev);
868 	int ret;
869 
870 	if (chip->vendor.irq)
871 		tpm_tis_reenable_interrupts(chip);
872 
873 	ret = tpm_pm_resume(dev);
874 	if (ret)
875 		return ret;
876 
877 	/* TPM 1.2 requires self-test on resume. This function actually returns
878 	 * an error code but for unknown reason it isn't handled.
879 	 */
880 	if (!(chip->flags & TPM_CHIP_FLAG_TPM2))
881 		tpm_do_selftest(chip);
882 
883 	return 0;
884 }
885 #endif
886 
887 static SIMPLE_DEV_PM_OPS(tpm_tis_pm, tpm_pm_suspend, tpm_tis_resume);
888 
889 #ifdef CONFIG_PNP
890 static int tpm_tis_pnp_init(struct pnp_dev *pnp_dev,
891 				      const struct pnp_device_id *pnp_id)
892 {
893 	resource_size_t start, len;
894 	unsigned int irq = 0;
895 	acpi_handle acpi_dev_handle = NULL;
896 
897 	start = pnp_mem_start(pnp_dev, 0);
898 	len = pnp_mem_len(pnp_dev, 0);
899 
900 	if (pnp_irq_valid(pnp_dev, 0))
901 		irq = pnp_irq(pnp_dev, 0);
902 	else
903 		interrupts = false;
904 
905 	if (is_itpm(pnp_dev))
906 		itpm = true;
907 
908 #ifdef CONFIG_ACPI
909 	if (pnp_acpi_device(pnp_dev))
910 		acpi_dev_handle = pnp_acpi_device(pnp_dev)->handle;
911 #endif
912 
913 	return tpm_tis_init(&pnp_dev->dev, acpi_dev_handle, start, len, irq);
914 }
915 
916 static struct pnp_device_id tpm_pnp_tbl[] = {
917 	{"PNP0C31", 0},		/* TPM */
918 	{"ATM1200", 0},		/* Atmel */
919 	{"IFX0102", 0},		/* Infineon */
920 	{"BCM0101", 0},		/* Broadcom */
921 	{"BCM0102", 0},		/* Broadcom */
922 	{"NSC1200", 0},		/* National */
923 	{"ICO0102", 0},		/* Intel */
924 	/* Add new here */
925 	{"", 0},		/* User Specified */
926 	{"", 0}			/* Terminator */
927 };
928 MODULE_DEVICE_TABLE(pnp, tpm_pnp_tbl);
929 
930 static void tpm_tis_pnp_remove(struct pnp_dev *dev)
931 {
932 	struct tpm_chip *chip = pnp_get_drvdata(dev);
933 	tpm_chip_unregister(chip);
934 	tpm_tis_remove(chip);
935 }
936 
937 static struct pnp_driver tis_pnp_driver = {
938 	.name = "tpm_tis",
939 	.id_table = tpm_pnp_tbl,
940 	.probe = tpm_tis_pnp_init,
941 	.remove = tpm_tis_pnp_remove,
942 	.driver	= {
943 		.pm = &tpm_tis_pm,
944 	},
945 };
946 
947 #define TIS_HID_USR_IDX sizeof(tpm_pnp_tbl)/sizeof(struct pnp_device_id) -2
948 module_param_string(hid, tpm_pnp_tbl[TIS_HID_USR_IDX].id,
949 		    sizeof(tpm_pnp_tbl[TIS_HID_USR_IDX].id), 0444);
950 MODULE_PARM_DESC(hid, "Set additional specific HID for this driver to probe");
951 #endif
952 
953 static struct platform_driver tis_drv = {
954 	.driver = {
955 		.name		= "tpm_tis",
956 		.pm		= &tpm_tis_pm,
957 	},
958 };
959 
960 static struct platform_device *pdev;
961 
962 static bool force;
963 module_param(force, bool, 0444);
964 MODULE_PARM_DESC(force, "Force device probe rather than using ACPI entry");
965 static int __init init_tis(void)
966 {
967 	int rc;
968 #ifdef CONFIG_PNP
969 	if (!force)
970 		return pnp_register_driver(&tis_pnp_driver);
971 #endif
972 
973 	rc = platform_driver_register(&tis_drv);
974 	if (rc < 0)
975 		return rc;
976 	pdev = platform_device_register_simple("tpm_tis", -1, NULL, 0);
977 	if (IS_ERR(pdev)) {
978 		rc = PTR_ERR(pdev);
979 		goto err_dev;
980 	}
981 	rc = tpm_tis_init(&pdev->dev, NULL, TIS_MEM_BASE, TIS_MEM_LEN, 0);
982 	if (rc)
983 		goto err_init;
984 	return 0;
985 err_init:
986 	platform_device_unregister(pdev);
987 err_dev:
988 	platform_driver_unregister(&tis_drv);
989 	return rc;
990 }
991 
992 static void __exit cleanup_tis(void)
993 {
994 	struct tpm_chip *chip;
995 #ifdef CONFIG_PNP
996 	if (!force) {
997 		pnp_unregister_driver(&tis_pnp_driver);
998 		return;
999 	}
1000 #endif
1001 	chip = dev_get_drvdata(&pdev->dev);
1002 	tpm_chip_unregister(chip);
1003 	tpm_tis_remove(chip);
1004 	platform_device_unregister(pdev);
1005 	platform_driver_unregister(&tis_drv);
1006 }
1007 
1008 module_init(init_tis);
1009 module_exit(cleanup_tis);
1010 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1011 MODULE_DESCRIPTION("TPM Driver");
1012 MODULE_VERSION("2.0");
1013 MODULE_LICENSE("GPL");
1014