xref: /openbmc/linux/drivers/char/tpm/tpm_ibmvtpm.c (revision 877013bc)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2012-2020 IBM Corporation
4  *
5  * Author: Ashley Lai <ashleydlai@gmail.com>
6  *
7  * Maintained by: <tpmdd-devel@lists.sourceforge.net>
8  *
9  * Device driver for TCG/TCPA TPM (trusted platform module).
10  * Specifications at www.trustedcomputinggroup.org
11  */
12 
13 #include <linux/dma-mapping.h>
14 #include <linux/dmapool.h>
15 #include <linux/slab.h>
16 #include <asm/vio.h>
17 #include <asm/irq.h>
18 #include <linux/types.h>
19 #include <linux/list.h>
20 #include <linux/spinlock.h>
21 #include <linux/interrupt.h>
22 #include <linux/wait.h>
23 #include <asm/prom.h>
24 
25 #include "tpm.h"
26 #include "tpm_ibmvtpm.h"
27 
28 static const char tpm_ibmvtpm_driver_name[] = "tpm_ibmvtpm";
29 
30 static const struct vio_device_id tpm_ibmvtpm_device_table[] = {
31 	{ "IBM,vtpm", "IBM,vtpm"},
32 	{ "IBM,vtpm", "IBM,vtpm20"},
33 	{ "", "" }
34 };
35 MODULE_DEVICE_TABLE(vio, tpm_ibmvtpm_device_table);
36 
37 /**
38  * ibmvtpm_send_crq_word() - Send a CRQ request
39  * @vdev:	vio device struct
40  * @w1:		pre-constructed first word of tpm crq (second word is reserved)
41  *
42  * Return:
43  *	0 - Success
44  *	Non-zero - Failure
45  */
46 static int ibmvtpm_send_crq_word(struct vio_dev *vdev, u64 w1)
47 {
48 	return plpar_hcall_norets(H_SEND_CRQ, vdev->unit_address, w1, 0);
49 }
50 
51 /**
52  * ibmvtpm_send_crq() - Send a CRQ request
53  *
54  * @vdev:	vio device struct
55  * @valid:	Valid field
56  * @msg:	Type field
57  * @len:	Length field
58  * @data:	Data field
59  *
60  * The ibmvtpm crq is defined as follows:
61  *
62  * Byte  |   0   |   1   |   2   |   3   |   4   |   5   |   6   |   7
63  * -----------------------------------------------------------------------
64  * Word0 | Valid | Type  |     Length    |              Data
65  * -----------------------------------------------------------------------
66  * Word1 |                Reserved
67  * -----------------------------------------------------------------------
68  *
69  * Which matches the following structure (on bigendian host):
70  *
71  * struct ibmvtpm_crq {
72  *         u8 valid;
73  *         u8 msg;
74  *         __be16 len;
75  *         __be32 data;
76  *         __be64 reserved;
77  * } __attribute__((packed, aligned(8)));
78  *
79  * However, the value is passed in a register so just compute the numeric value
80  * to load into the register avoiding byteswap altogether. Endian only affects
81  * memory loads and stores - registers are internally represented the same.
82  *
83  * Return:
84  *	0 (H_SUCCESS) - Success
85  *	Non-zero - Failure
86  */
87 static int ibmvtpm_send_crq(struct vio_dev *vdev,
88 		u8 valid, u8 msg, u16 len, u32 data)
89 {
90 	u64 w1 = ((u64)valid << 56) | ((u64)msg << 48) | ((u64)len << 32) |
91 		(u64)data;
92 	return ibmvtpm_send_crq_word(vdev, w1);
93 }
94 
95 /**
96  * tpm_ibmvtpm_recv - Receive data after send
97  *
98  * @chip:	tpm chip struct
99  * @buf:	buffer to read
100  * @count:	size of buffer
101  *
102  * Return:
103  *	Number of bytes read
104  */
105 static int tpm_ibmvtpm_recv(struct tpm_chip *chip, u8 *buf, size_t count)
106 {
107 	struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev);
108 	u16 len;
109 	int sig;
110 
111 	if (!ibmvtpm->rtce_buf) {
112 		dev_err(ibmvtpm->dev, "ibmvtpm device is not ready\n");
113 		return 0;
114 	}
115 
116 	sig = wait_event_interruptible(ibmvtpm->wq, !ibmvtpm->tpm_processing_cmd);
117 	if (sig)
118 		return -EINTR;
119 
120 	len = ibmvtpm->res_len;
121 
122 	if (count < len) {
123 		dev_err(ibmvtpm->dev,
124 			"Invalid size in recv: count=%zd, crq_size=%d\n",
125 			count, len);
126 		return -EIO;
127 	}
128 
129 	spin_lock(&ibmvtpm->rtce_lock);
130 	memcpy((void *)buf, (void *)ibmvtpm->rtce_buf, len);
131 	memset(ibmvtpm->rtce_buf, 0, len);
132 	ibmvtpm->res_len = 0;
133 	spin_unlock(&ibmvtpm->rtce_lock);
134 	return len;
135 }
136 
137 /**
138  * ibmvtpm_crq_send_init - Send a CRQ initialize message
139  * @ibmvtpm:	vtpm device struct
140  *
141  * Return:
142  *	0 on success.
143  *	Non-zero on failure.
144  */
145 static int ibmvtpm_crq_send_init(struct ibmvtpm_dev *ibmvtpm)
146 {
147 	int rc;
148 
149 	rc = ibmvtpm_send_crq_word(ibmvtpm->vdev, INIT_CRQ_CMD);
150 	if (rc != H_SUCCESS)
151 		dev_err(ibmvtpm->dev,
152 			"%s failed rc=%d\n", __func__, rc);
153 
154 	return rc;
155 }
156 
157 /**
158  * tpm_ibmvtpm_resume - Resume from suspend
159  *
160  * @dev:	device struct
161  *
162  * Return: Always 0.
163  */
164 static int tpm_ibmvtpm_resume(struct device *dev)
165 {
166 	struct tpm_chip *chip = dev_get_drvdata(dev);
167 	struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev);
168 	int rc = 0;
169 
170 	do {
171 		if (rc)
172 			msleep(100);
173 		rc = plpar_hcall_norets(H_ENABLE_CRQ,
174 					ibmvtpm->vdev->unit_address);
175 	} while (rc == H_IN_PROGRESS || rc == H_BUSY || H_IS_LONG_BUSY(rc));
176 
177 	if (rc) {
178 		dev_err(dev, "Error enabling ibmvtpm rc=%d\n", rc);
179 		return rc;
180 	}
181 
182 	rc = vio_enable_interrupts(ibmvtpm->vdev);
183 	if (rc) {
184 		dev_err(dev, "Error vio_enable_interrupts rc=%d\n", rc);
185 		return rc;
186 	}
187 
188 	rc = ibmvtpm_crq_send_init(ibmvtpm);
189 	if (rc)
190 		dev_err(dev, "Error send_init rc=%d\n", rc);
191 
192 	return rc;
193 }
194 
195 /**
196  * tpm_ibmvtpm_send() - Send a TPM command
197  * @chip:	tpm chip struct
198  * @buf:	buffer contains data to send
199  * @count:	size of buffer
200  *
201  * Return:
202  *   0 on success,
203  *   -errno on error
204  */
205 static int tpm_ibmvtpm_send(struct tpm_chip *chip, u8 *buf, size_t count)
206 {
207 	struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev);
208 	bool retry = true;
209 	int rc, sig;
210 
211 	if (!ibmvtpm->rtce_buf) {
212 		dev_err(ibmvtpm->dev, "ibmvtpm device is not ready\n");
213 		return 0;
214 	}
215 
216 	if (count > ibmvtpm->rtce_size) {
217 		dev_err(ibmvtpm->dev,
218 			"Invalid size in send: count=%zd, rtce_size=%d\n",
219 			count, ibmvtpm->rtce_size);
220 		return -EIO;
221 	}
222 
223 	if (ibmvtpm->tpm_processing_cmd) {
224 		dev_info(ibmvtpm->dev,
225 		         "Need to wait for TPM to finish\n");
226 		/* wait for previous command to finish */
227 		sig = wait_event_interruptible(ibmvtpm->wq, !ibmvtpm->tpm_processing_cmd);
228 		if (sig)
229 			return -EINTR;
230 	}
231 
232 	spin_lock(&ibmvtpm->rtce_lock);
233 	ibmvtpm->res_len = 0;
234 	memcpy((void *)ibmvtpm->rtce_buf, (void *)buf, count);
235 
236 	/*
237 	 * set the processing flag before the Hcall, since we may get the
238 	 * result (interrupt) before even being able to check rc.
239 	 */
240 	ibmvtpm->tpm_processing_cmd = true;
241 
242 again:
243 	rc = ibmvtpm_send_crq(ibmvtpm->vdev,
244 			IBMVTPM_VALID_CMD, VTPM_TPM_COMMAND,
245 			count, ibmvtpm->rtce_dma_handle);
246 	if (rc != H_SUCCESS) {
247 		/*
248 		 * H_CLOSED can be returned after LPM resume.  Call
249 		 * tpm_ibmvtpm_resume() to re-enable the CRQ then retry
250 		 * ibmvtpm_send_crq() once before failing.
251 		 */
252 		if (rc == H_CLOSED && retry) {
253 			tpm_ibmvtpm_resume(ibmvtpm->dev);
254 			retry = false;
255 			goto again;
256 		}
257 		dev_err(ibmvtpm->dev, "tpm_ibmvtpm_send failed rc=%d\n", rc);
258 		ibmvtpm->tpm_processing_cmd = false;
259 	}
260 
261 	spin_unlock(&ibmvtpm->rtce_lock);
262 	return 0;
263 }
264 
265 static void tpm_ibmvtpm_cancel(struct tpm_chip *chip)
266 {
267 	return;
268 }
269 
270 static u8 tpm_ibmvtpm_status(struct tpm_chip *chip)
271 {
272 	return 0;
273 }
274 
275 /**
276  * ibmvtpm_crq_get_rtce_size - Send a CRQ request to get rtce size
277  *
278  * @ibmvtpm:	vtpm device struct
279  *
280  * Return:
281  *	0 on success.
282  *	Non-zero on failure.
283  */
284 static int ibmvtpm_crq_get_rtce_size(struct ibmvtpm_dev *ibmvtpm)
285 {
286 	int rc;
287 
288 	rc = ibmvtpm_send_crq(ibmvtpm->vdev,
289 			IBMVTPM_VALID_CMD, VTPM_GET_RTCE_BUFFER_SIZE, 0, 0);
290 	if (rc != H_SUCCESS)
291 		dev_err(ibmvtpm->dev,
292 			"ibmvtpm_crq_get_rtce_size failed rc=%d\n", rc);
293 
294 	return rc;
295 }
296 
297 /**
298  * ibmvtpm_crq_get_version - Send a CRQ request to get vtpm version
299  *			   - Note that this is vtpm version and not tpm version
300  *
301  * @ibmvtpm:	vtpm device struct
302  *
303  * Return:
304  *	0 on success.
305  *	Non-zero on failure.
306  */
307 static int ibmvtpm_crq_get_version(struct ibmvtpm_dev *ibmvtpm)
308 {
309 	int rc;
310 
311 	rc = ibmvtpm_send_crq(ibmvtpm->vdev,
312 			IBMVTPM_VALID_CMD, VTPM_GET_VERSION, 0, 0);
313 	if (rc != H_SUCCESS)
314 		dev_err(ibmvtpm->dev,
315 			"ibmvtpm_crq_get_version failed rc=%d\n", rc);
316 
317 	return rc;
318 }
319 
320 /**
321  * ibmvtpm_crq_send_init_complete - Send a CRQ initialize complete message
322  * @ibmvtpm:	vtpm device struct
323  *
324  * Return:
325  *	0 on success.
326  *	Non-zero on failure.
327  */
328 static int ibmvtpm_crq_send_init_complete(struct ibmvtpm_dev *ibmvtpm)
329 {
330 	int rc;
331 
332 	rc = ibmvtpm_send_crq_word(ibmvtpm->vdev, INIT_CRQ_COMP_CMD);
333 	if (rc != H_SUCCESS)
334 		dev_err(ibmvtpm->dev,
335 			"ibmvtpm_crq_send_init_complete failed rc=%d\n", rc);
336 
337 	return rc;
338 }
339 
340 /**
341  * tpm_ibmvtpm_remove - ibm vtpm remove entry point
342  * @vdev:	vio device struct
343  *
344  * Return: Always 0.
345  */
346 static void tpm_ibmvtpm_remove(struct vio_dev *vdev)
347 {
348 	struct tpm_chip *chip = dev_get_drvdata(&vdev->dev);
349 	struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev);
350 	int rc = 0;
351 
352 	tpm_chip_unregister(chip);
353 
354 	free_irq(vdev->irq, ibmvtpm);
355 
356 	do {
357 		if (rc)
358 			msleep(100);
359 		rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
360 	} while (rc == H_BUSY || H_IS_LONG_BUSY(rc));
361 
362 	dma_unmap_single(ibmvtpm->dev, ibmvtpm->crq_dma_handle,
363 			 CRQ_RES_BUF_SIZE, DMA_BIDIRECTIONAL);
364 	free_page((unsigned long)ibmvtpm->crq_queue.crq_addr);
365 
366 	if (ibmvtpm->rtce_buf) {
367 		dma_unmap_single(ibmvtpm->dev, ibmvtpm->rtce_dma_handle,
368 				 ibmvtpm->rtce_size, DMA_BIDIRECTIONAL);
369 		kfree(ibmvtpm->rtce_buf);
370 	}
371 
372 	kfree(ibmvtpm);
373 	/* For tpm_ibmvtpm_get_desired_dma */
374 	dev_set_drvdata(&vdev->dev, NULL);
375 }
376 
377 /**
378  * tpm_ibmvtpm_get_desired_dma - Get DMA size needed by this driver
379  * @vdev:	vio device struct
380  *
381  * Return:
382  *	Number of bytes the driver needs to DMA map.
383  */
384 static unsigned long tpm_ibmvtpm_get_desired_dma(struct vio_dev *vdev)
385 {
386 	struct tpm_chip *chip = dev_get_drvdata(&vdev->dev);
387 	struct ibmvtpm_dev *ibmvtpm;
388 
389 	/*
390 	 * ibmvtpm initializes at probe time, so the data we are
391 	 * asking for may not be set yet. Estimate that 4K required
392 	 * for TCE-mapped buffer in addition to CRQ.
393 	 */
394 	if (chip)
395 		ibmvtpm = dev_get_drvdata(&chip->dev);
396 	else
397 		return CRQ_RES_BUF_SIZE + PAGE_SIZE;
398 
399 	return CRQ_RES_BUF_SIZE + ibmvtpm->rtce_size;
400 }
401 
402 /**
403  * tpm_ibmvtpm_suspend - Suspend
404  * @dev:	device struct
405  *
406  * Return: Always 0.
407  */
408 static int tpm_ibmvtpm_suspend(struct device *dev)
409 {
410 	struct tpm_chip *chip = dev_get_drvdata(dev);
411 	struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev);
412 	int rc = 0;
413 
414 	rc = ibmvtpm_send_crq(ibmvtpm->vdev,
415 			IBMVTPM_VALID_CMD, VTPM_PREPARE_TO_SUSPEND, 0, 0);
416 	if (rc != H_SUCCESS)
417 		dev_err(ibmvtpm->dev,
418 			"tpm_ibmvtpm_suspend failed rc=%d\n", rc);
419 
420 	return rc;
421 }
422 
423 /**
424  * ibmvtpm_reset_crq - Reset CRQ
425  *
426  * @ibmvtpm:	ibm vtpm struct
427  *
428  * Return:
429  *	0 on success.
430  *	Non-zero on failure.
431  */
432 static int ibmvtpm_reset_crq(struct ibmvtpm_dev *ibmvtpm)
433 {
434 	int rc = 0;
435 
436 	do {
437 		if (rc)
438 			msleep(100);
439 		rc = plpar_hcall_norets(H_FREE_CRQ,
440 					ibmvtpm->vdev->unit_address);
441 	} while (rc == H_BUSY || H_IS_LONG_BUSY(rc));
442 
443 	memset(ibmvtpm->crq_queue.crq_addr, 0, CRQ_RES_BUF_SIZE);
444 	ibmvtpm->crq_queue.index = 0;
445 
446 	return plpar_hcall_norets(H_REG_CRQ, ibmvtpm->vdev->unit_address,
447 				  ibmvtpm->crq_dma_handle, CRQ_RES_BUF_SIZE);
448 }
449 
450 static bool tpm_ibmvtpm_req_canceled(struct tpm_chip *chip, u8 status)
451 {
452 	return (status == 0);
453 }
454 
455 static const struct tpm_class_ops tpm_ibmvtpm = {
456 	.recv = tpm_ibmvtpm_recv,
457 	.send = tpm_ibmvtpm_send,
458 	.cancel = tpm_ibmvtpm_cancel,
459 	.status = tpm_ibmvtpm_status,
460 	.req_complete_mask = 0,
461 	.req_complete_val = 0,
462 	.req_canceled = tpm_ibmvtpm_req_canceled,
463 };
464 
465 static const struct dev_pm_ops tpm_ibmvtpm_pm_ops = {
466 	.suspend = tpm_ibmvtpm_suspend,
467 	.resume = tpm_ibmvtpm_resume,
468 };
469 
470 /**
471  * ibmvtpm_crq_get_next - Get next responded crq
472  *
473  * @ibmvtpm:	vtpm device struct
474  *
475  * Return: vtpm crq pointer or NULL.
476  */
477 static struct ibmvtpm_crq *ibmvtpm_crq_get_next(struct ibmvtpm_dev *ibmvtpm)
478 {
479 	struct ibmvtpm_crq_queue *crq_q = &ibmvtpm->crq_queue;
480 	struct ibmvtpm_crq *crq = &crq_q->crq_addr[crq_q->index];
481 
482 	if (crq->valid & VTPM_MSG_RES) {
483 		if (++crq_q->index == crq_q->num_entry)
484 			crq_q->index = 0;
485 		smp_rmb();
486 	} else
487 		crq = NULL;
488 	return crq;
489 }
490 
491 /**
492  * ibmvtpm_crq_process - Process responded crq
493  *
494  * @crq:	crq to be processed
495  * @ibmvtpm:	vtpm device struct
496  *
497  */
498 static void ibmvtpm_crq_process(struct ibmvtpm_crq *crq,
499 				struct ibmvtpm_dev *ibmvtpm)
500 {
501 	int rc = 0;
502 
503 	switch (crq->valid) {
504 	case VALID_INIT_CRQ:
505 		switch (crq->msg) {
506 		case INIT_CRQ_RES:
507 			dev_info(ibmvtpm->dev, "CRQ initialized\n");
508 			rc = ibmvtpm_crq_send_init_complete(ibmvtpm);
509 			if (rc)
510 				dev_err(ibmvtpm->dev, "Unable to send CRQ init complete rc=%d\n", rc);
511 			return;
512 		case INIT_CRQ_COMP_RES:
513 			dev_info(ibmvtpm->dev,
514 				 "CRQ initialization completed\n");
515 			return;
516 		default:
517 			dev_err(ibmvtpm->dev, "Unknown crq message type: %d\n", crq->msg);
518 			return;
519 		}
520 	case IBMVTPM_VALID_CMD:
521 		switch (crq->msg) {
522 		case VTPM_GET_RTCE_BUFFER_SIZE_RES:
523 			if (be16_to_cpu(crq->len) <= 0) {
524 				dev_err(ibmvtpm->dev, "Invalid rtce size\n");
525 				return;
526 			}
527 			ibmvtpm->rtce_size = be16_to_cpu(crq->len);
528 			ibmvtpm->rtce_buf = kmalloc(ibmvtpm->rtce_size,
529 						    GFP_ATOMIC);
530 			if (!ibmvtpm->rtce_buf) {
531 				dev_err(ibmvtpm->dev, "Failed to allocate memory for rtce buffer\n");
532 				return;
533 			}
534 
535 			ibmvtpm->rtce_dma_handle = dma_map_single(ibmvtpm->dev,
536 				ibmvtpm->rtce_buf, ibmvtpm->rtce_size,
537 				DMA_BIDIRECTIONAL);
538 
539 			if (dma_mapping_error(ibmvtpm->dev,
540 					      ibmvtpm->rtce_dma_handle)) {
541 				kfree(ibmvtpm->rtce_buf);
542 				ibmvtpm->rtce_buf = NULL;
543 				dev_err(ibmvtpm->dev, "Failed to dma map rtce buffer\n");
544 			}
545 
546 			return;
547 		case VTPM_GET_VERSION_RES:
548 			ibmvtpm->vtpm_version = be32_to_cpu(crq->data);
549 			return;
550 		case VTPM_TPM_COMMAND_RES:
551 			/* len of the data in rtce buffer */
552 			ibmvtpm->res_len = be16_to_cpu(crq->len);
553 			ibmvtpm->tpm_processing_cmd = false;
554 			wake_up_interruptible(&ibmvtpm->wq);
555 			return;
556 		default:
557 			return;
558 		}
559 	}
560 	return;
561 }
562 
563 /**
564  * ibmvtpm_interrupt -	Interrupt handler
565  *
566  * @irq:		irq number to handle
567  * @vtpm_instance:	vtpm that received interrupt
568  *
569  * Returns:
570  *	IRQ_HANDLED
571  **/
572 static irqreturn_t ibmvtpm_interrupt(int irq, void *vtpm_instance)
573 {
574 	struct ibmvtpm_dev *ibmvtpm = (struct ibmvtpm_dev *) vtpm_instance;
575 	struct ibmvtpm_crq *crq;
576 
577 	/* while loop is needed for initial setup (get version and
578 	 * get rtce_size). There should be only one tpm request at any
579 	 * given time.
580 	 */
581 	while ((crq = ibmvtpm_crq_get_next(ibmvtpm)) != NULL) {
582 		ibmvtpm_crq_process(crq, ibmvtpm);
583 		wake_up_interruptible(&ibmvtpm->crq_queue.wq);
584 		crq->valid = 0;
585 		smp_wmb();
586 	}
587 
588 	return IRQ_HANDLED;
589 }
590 
591 /**
592  * tpm_ibmvtpm_probe - ibm vtpm initialize entry point
593  *
594  * @vio_dev:	vio device struct
595  * @id:		vio device id struct
596  *
597  * Return:
598  *	0 on success.
599  *	Non-zero on failure.
600  */
601 static int tpm_ibmvtpm_probe(struct vio_dev *vio_dev,
602 				   const struct vio_device_id *id)
603 {
604 	struct ibmvtpm_dev *ibmvtpm;
605 	struct device *dev = &vio_dev->dev;
606 	struct ibmvtpm_crq_queue *crq_q;
607 	struct tpm_chip *chip;
608 	int rc = -ENOMEM, rc1;
609 
610 	chip = tpmm_chip_alloc(dev, &tpm_ibmvtpm);
611 	if (IS_ERR(chip))
612 		return PTR_ERR(chip);
613 
614 	ibmvtpm = kzalloc(sizeof(struct ibmvtpm_dev), GFP_KERNEL);
615 	if (!ibmvtpm) {
616 		dev_err(dev, "kzalloc for ibmvtpm failed\n");
617 		goto cleanup;
618 	}
619 
620 	ibmvtpm->dev = dev;
621 	ibmvtpm->vdev = vio_dev;
622 
623 	crq_q = &ibmvtpm->crq_queue;
624 	crq_q->crq_addr = (struct ibmvtpm_crq *)get_zeroed_page(GFP_KERNEL);
625 	if (!crq_q->crq_addr) {
626 		dev_err(dev, "Unable to allocate memory for crq_addr\n");
627 		goto cleanup;
628 	}
629 
630 	crq_q->num_entry = CRQ_RES_BUF_SIZE / sizeof(*crq_q->crq_addr);
631 	init_waitqueue_head(&crq_q->wq);
632 	ibmvtpm->crq_dma_handle = dma_map_single(dev, crq_q->crq_addr,
633 						 CRQ_RES_BUF_SIZE,
634 						 DMA_BIDIRECTIONAL);
635 
636 	if (dma_mapping_error(dev, ibmvtpm->crq_dma_handle)) {
637 		dev_err(dev, "dma mapping failed\n");
638 		goto cleanup;
639 	}
640 
641 	rc = plpar_hcall_norets(H_REG_CRQ, vio_dev->unit_address,
642 				ibmvtpm->crq_dma_handle, CRQ_RES_BUF_SIZE);
643 	if (rc == H_RESOURCE)
644 		rc = ibmvtpm_reset_crq(ibmvtpm);
645 
646 	if (rc) {
647 		dev_err(dev, "Unable to register CRQ rc=%d\n", rc);
648 		goto reg_crq_cleanup;
649 	}
650 
651 	rc = request_irq(vio_dev->irq, ibmvtpm_interrupt, 0,
652 			 tpm_ibmvtpm_driver_name, ibmvtpm);
653 	if (rc) {
654 		dev_err(dev, "Error %d register irq 0x%x\n", rc, vio_dev->irq);
655 		goto init_irq_cleanup;
656 	}
657 
658 	rc = vio_enable_interrupts(vio_dev);
659 	if (rc) {
660 		dev_err(dev, "Error %d enabling interrupts\n", rc);
661 		goto init_irq_cleanup;
662 	}
663 
664 	init_waitqueue_head(&ibmvtpm->wq);
665 
666 	crq_q->index = 0;
667 
668 	dev_set_drvdata(&chip->dev, ibmvtpm);
669 
670 	spin_lock_init(&ibmvtpm->rtce_lock);
671 
672 	rc = ibmvtpm_crq_send_init(ibmvtpm);
673 	if (rc)
674 		goto init_irq_cleanup;
675 
676 	rc = ibmvtpm_crq_get_version(ibmvtpm);
677 	if (rc)
678 		goto init_irq_cleanup;
679 
680 	rc = ibmvtpm_crq_get_rtce_size(ibmvtpm);
681 	if (rc)
682 		goto init_irq_cleanup;
683 
684 	if (!wait_event_timeout(ibmvtpm->crq_queue.wq,
685 				ibmvtpm->rtce_buf != NULL,
686 				HZ)) {
687 		dev_err(dev, "CRQ response timed out\n");
688 		goto init_irq_cleanup;
689 	}
690 
691 	if (!strcmp(id->compat, "IBM,vtpm20")) {
692 		chip->flags |= TPM_CHIP_FLAG_TPM2;
693 		rc = tpm2_get_cc_attrs_tbl(chip);
694 		if (rc)
695 			goto init_irq_cleanup;
696 	}
697 
698 	return tpm_chip_register(chip);
699 init_irq_cleanup:
700 	do {
701 		rc1 = plpar_hcall_norets(H_FREE_CRQ, vio_dev->unit_address);
702 	} while (rc1 == H_BUSY || H_IS_LONG_BUSY(rc1));
703 reg_crq_cleanup:
704 	dma_unmap_single(dev, ibmvtpm->crq_dma_handle, CRQ_RES_BUF_SIZE,
705 			 DMA_BIDIRECTIONAL);
706 cleanup:
707 	if (ibmvtpm) {
708 		if (crq_q->crq_addr)
709 			free_page((unsigned long)crq_q->crq_addr);
710 		kfree(ibmvtpm);
711 	}
712 
713 	return rc;
714 }
715 
716 static struct vio_driver ibmvtpm_driver = {
717 	.id_table	 = tpm_ibmvtpm_device_table,
718 	.probe		 = tpm_ibmvtpm_probe,
719 	.remove		 = tpm_ibmvtpm_remove,
720 	.get_desired_dma = tpm_ibmvtpm_get_desired_dma,
721 	.name		 = tpm_ibmvtpm_driver_name,
722 	.pm		 = &tpm_ibmvtpm_pm_ops,
723 };
724 
725 /**
726  * ibmvtpm_module_init - Initialize ibm vtpm module.
727  *
728  *
729  * Return:
730  *	0 on success.
731  *	Non-zero on failure.
732  */
733 static int __init ibmvtpm_module_init(void)
734 {
735 	return vio_register_driver(&ibmvtpm_driver);
736 }
737 
738 /**
739  * ibmvtpm_module_exit - Tear down ibm vtpm module.
740  */
741 static void __exit ibmvtpm_module_exit(void)
742 {
743 	vio_unregister_driver(&ibmvtpm_driver);
744 }
745 
746 module_init(ibmvtpm_module_init);
747 module_exit(ibmvtpm_module_exit);
748 
749 MODULE_AUTHOR("adlai@us.ibm.com");
750 MODULE_DESCRIPTION("IBM vTPM Driver");
751 MODULE_VERSION("1.0");
752 MODULE_LICENSE("GPL");
753