xref: /linux/drivers/char/tpm/tpm_ibmvtpm.c (revision 46d22bfdf0bc76429f596c58ca74a8f67d0f6251)
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  */
ibmvtpm_send_crq_word(struct vio_dev * vdev,u64 w1)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  */
ibmvtpm_send_crq(struct vio_dev * vdev,u8 valid,u8 msg,u16 len,u32 data)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  */
tpm_ibmvtpm_recv(struct tpm_chip * chip,u8 * buf,size_t count)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 
110 	if (!ibmvtpm->rtce_buf) {
111 		dev_err(ibmvtpm->dev, "ibmvtpm device is not ready\n");
112 		return 0;
113 	}
114 
115 	len = ibmvtpm->res_len;
116 
117 	if (count < len) {
118 		dev_err(ibmvtpm->dev,
119 			"Invalid size in recv: count=%zd, crq_size=%d\n",
120 			count, len);
121 		return -EIO;
122 	}
123 
124 	spin_lock(&ibmvtpm->rtce_lock);
125 	memcpy((void *)buf, (void *)ibmvtpm->rtce_buf, len);
126 	memset(ibmvtpm->rtce_buf, 0, len);
127 	ibmvtpm->res_len = 0;
128 	spin_unlock(&ibmvtpm->rtce_lock);
129 	return len;
130 }
131 
132 /**
133  * ibmvtpm_crq_send_init - Send a CRQ initialize message
134  * @ibmvtpm:	vtpm device struct
135  *
136  * Return:
137  *	0 on success.
138  *	Non-zero on failure.
139  */
ibmvtpm_crq_send_init(struct ibmvtpm_dev * ibmvtpm)140 static int ibmvtpm_crq_send_init(struct ibmvtpm_dev *ibmvtpm)
141 {
142 	int rc;
143 
144 	rc = ibmvtpm_send_crq_word(ibmvtpm->vdev, INIT_CRQ_CMD);
145 	if (rc != H_SUCCESS)
146 		dev_err(ibmvtpm->dev,
147 			"%s failed rc=%d\n", __func__, rc);
148 
149 	return rc;
150 }
151 
152 /**
153  * tpm_ibmvtpm_resume - Resume from suspend
154  *
155  * @dev:	device struct
156  *
157  * Return: Always 0.
158  */
tpm_ibmvtpm_resume(struct device * dev)159 static int tpm_ibmvtpm_resume(struct device *dev)
160 {
161 	struct tpm_chip *chip = dev_get_drvdata(dev);
162 	struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev);
163 	int rc = 0;
164 
165 	do {
166 		if (rc)
167 			msleep(100);
168 		rc = plpar_hcall_norets(H_ENABLE_CRQ,
169 					ibmvtpm->vdev->unit_address);
170 	} while (rc == H_IN_PROGRESS || rc == H_BUSY || H_IS_LONG_BUSY(rc));
171 
172 	if (rc) {
173 		dev_err(dev, "Error enabling ibmvtpm rc=%d\n", rc);
174 		return rc;
175 	}
176 
177 	rc = vio_enable_interrupts(ibmvtpm->vdev);
178 	if (rc) {
179 		dev_err(dev, "Error vio_enable_interrupts rc=%d\n", rc);
180 		return rc;
181 	}
182 
183 	rc = ibmvtpm_crq_send_init(ibmvtpm);
184 	if (rc)
185 		dev_err(dev, "Error send_init rc=%d\n", rc);
186 
187 	return rc;
188 }
189 
190 /**
191  * tpm_ibmvtpm_send() - Send a TPM command
192  * @chip:	tpm chip struct
193  * @buf:	buffer contains data to send
194  * @count:	size of buffer
195  *
196  * Return:
197  *   0 on success,
198  *   -errno on error
199  */
tpm_ibmvtpm_send(struct tpm_chip * chip,u8 * buf,size_t count)200 static int tpm_ibmvtpm_send(struct tpm_chip *chip, u8 *buf, size_t count)
201 {
202 	struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev);
203 	bool retry = true;
204 	int rc, sig;
205 
206 	if (!ibmvtpm->rtce_buf) {
207 		dev_err(ibmvtpm->dev, "ibmvtpm device is not ready\n");
208 		return 0;
209 	}
210 
211 	if (count > ibmvtpm->rtce_size) {
212 		dev_err(ibmvtpm->dev,
213 			"Invalid size in send: count=%zd, rtce_size=%d\n",
214 			count, ibmvtpm->rtce_size);
215 		return -EIO;
216 	}
217 
218 	if (ibmvtpm->tpm_processing_cmd) {
219 		dev_info(ibmvtpm->dev,
220 		         "Need to wait for TPM to finish\n");
221 		/* wait for previous command to finish */
222 		sig = wait_event_interruptible(ibmvtpm->wq, !ibmvtpm->tpm_processing_cmd);
223 		if (sig)
224 			return -EINTR;
225 	}
226 
227 	spin_lock(&ibmvtpm->rtce_lock);
228 	ibmvtpm->res_len = 0;
229 	memcpy((void *)ibmvtpm->rtce_buf, (void *)buf, count);
230 
231 	/*
232 	 * set the processing flag before the Hcall, since we may get the
233 	 * result (interrupt) before even being able to check rc.
234 	 */
235 	ibmvtpm->tpm_processing_cmd = 1;
236 
237 again:
238 	rc = ibmvtpm_send_crq(ibmvtpm->vdev,
239 			IBMVTPM_VALID_CMD, VTPM_TPM_COMMAND,
240 			count, ibmvtpm->rtce_dma_handle);
241 	if (rc != H_SUCCESS) {
242 		/*
243 		 * H_CLOSED can be returned after LPM resume.  Call
244 		 * tpm_ibmvtpm_resume() to re-enable the CRQ then retry
245 		 * ibmvtpm_send_crq() once before failing.
246 		 */
247 		if (rc == H_CLOSED && retry) {
248 			tpm_ibmvtpm_resume(ibmvtpm->dev);
249 			retry = false;
250 			goto again;
251 		}
252 		dev_err(ibmvtpm->dev, "tpm_ibmvtpm_send failed rc=%d\n", rc);
253 		ibmvtpm->tpm_processing_cmd = 0;
254 	}
255 
256 	spin_unlock(&ibmvtpm->rtce_lock);
257 	return 0;
258 }
259 
tpm_ibmvtpm_cancel(struct tpm_chip * chip)260 static void tpm_ibmvtpm_cancel(struct tpm_chip *chip)
261 {
262 	return;
263 }
264 
tpm_ibmvtpm_status(struct tpm_chip * chip)265 static u8 tpm_ibmvtpm_status(struct tpm_chip *chip)
266 {
267 	struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev);
268 
269 	return ibmvtpm->tpm_processing_cmd;
270 }
271 
272 /**
273  * ibmvtpm_crq_get_rtce_size - Send a CRQ request to get rtce size
274  *
275  * @ibmvtpm:	vtpm device struct
276  *
277  * Return:
278  *	0 on success.
279  *	Non-zero on failure.
280  */
ibmvtpm_crq_get_rtce_size(struct ibmvtpm_dev * ibmvtpm)281 static int ibmvtpm_crq_get_rtce_size(struct ibmvtpm_dev *ibmvtpm)
282 {
283 	int rc;
284 
285 	rc = ibmvtpm_send_crq(ibmvtpm->vdev,
286 			IBMVTPM_VALID_CMD, VTPM_GET_RTCE_BUFFER_SIZE, 0, 0);
287 	if (rc != H_SUCCESS)
288 		dev_err(ibmvtpm->dev,
289 			"ibmvtpm_crq_get_rtce_size failed rc=%d\n", rc);
290 
291 	return rc;
292 }
293 
294 /**
295  * ibmvtpm_crq_get_version - Send a CRQ request to get vtpm version
296  *			   - Note that this is vtpm version and not tpm version
297  *
298  * @ibmvtpm:	vtpm device struct
299  *
300  * Return:
301  *	0 on success.
302  *	Non-zero on failure.
303  */
ibmvtpm_crq_get_version(struct ibmvtpm_dev * ibmvtpm)304 static int ibmvtpm_crq_get_version(struct ibmvtpm_dev *ibmvtpm)
305 {
306 	int rc;
307 
308 	rc = ibmvtpm_send_crq(ibmvtpm->vdev,
309 			IBMVTPM_VALID_CMD, VTPM_GET_VERSION, 0, 0);
310 	if (rc != H_SUCCESS)
311 		dev_err(ibmvtpm->dev,
312 			"ibmvtpm_crq_get_version failed rc=%d\n", rc);
313 
314 	return rc;
315 }
316 
317 /**
318  * ibmvtpm_crq_send_init_complete - Send a CRQ initialize complete message
319  * @ibmvtpm:	vtpm device struct
320  *
321  * Return:
322  *	0 on success.
323  *	Non-zero on failure.
324  */
ibmvtpm_crq_send_init_complete(struct ibmvtpm_dev * ibmvtpm)325 static int ibmvtpm_crq_send_init_complete(struct ibmvtpm_dev *ibmvtpm)
326 {
327 	int rc;
328 
329 	rc = ibmvtpm_send_crq_word(ibmvtpm->vdev, INIT_CRQ_COMP_CMD);
330 	if (rc != H_SUCCESS)
331 		dev_err(ibmvtpm->dev,
332 			"ibmvtpm_crq_send_init_complete failed rc=%d\n", rc);
333 
334 	return rc;
335 }
336 
337 /**
338  * tpm_ibmvtpm_remove - ibm vtpm remove entry point
339  * @vdev:	vio device struct
340  *
341  * Return: Always 0.
342  */
tpm_ibmvtpm_remove(struct vio_dev * vdev)343 static void tpm_ibmvtpm_remove(struct vio_dev *vdev)
344 {
345 	struct tpm_chip *chip = dev_get_drvdata(&vdev->dev);
346 	struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev);
347 	int rc = 0;
348 
349 	tpm_chip_unregister(chip);
350 
351 	free_irq(vdev->irq, ibmvtpm);
352 
353 	do {
354 		if (rc)
355 			msleep(100);
356 		rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
357 	} while (rc == H_BUSY || H_IS_LONG_BUSY(rc));
358 
359 	dma_unmap_single(ibmvtpm->dev, ibmvtpm->crq_dma_handle,
360 			 CRQ_RES_BUF_SIZE, DMA_BIDIRECTIONAL);
361 	free_page((unsigned long)ibmvtpm->crq_queue.crq_addr);
362 
363 	if (ibmvtpm->rtce_buf) {
364 		dma_unmap_single(ibmvtpm->dev, ibmvtpm->rtce_dma_handle,
365 				 ibmvtpm->rtce_size, DMA_BIDIRECTIONAL);
366 		kfree(ibmvtpm->rtce_buf);
367 	}
368 
369 	kfree(ibmvtpm);
370 	/* For tpm_ibmvtpm_get_desired_dma */
371 	dev_set_drvdata(&vdev->dev, NULL);
372 }
373 
374 /**
375  * tpm_ibmvtpm_get_desired_dma - Get DMA size needed by this driver
376  * @vdev:	vio device struct
377  *
378  * Return:
379  *	Number of bytes the driver needs to DMA map.
380  */
tpm_ibmvtpm_get_desired_dma(struct vio_dev * vdev)381 static unsigned long tpm_ibmvtpm_get_desired_dma(struct vio_dev *vdev)
382 {
383 	struct tpm_chip *chip = dev_get_drvdata(&vdev->dev);
384 	struct ibmvtpm_dev *ibmvtpm;
385 
386 	/*
387 	 * ibmvtpm initializes at probe time, so the data we are
388 	 * asking for may not be set yet. Estimate that 4K required
389 	 * for TCE-mapped buffer in addition to CRQ.
390 	 */
391 	if (chip)
392 		ibmvtpm = dev_get_drvdata(&chip->dev);
393 	else
394 		return CRQ_RES_BUF_SIZE + PAGE_SIZE;
395 
396 	return CRQ_RES_BUF_SIZE + ibmvtpm->rtce_size;
397 }
398 
399 /**
400  * tpm_ibmvtpm_suspend - Suspend
401  * @dev:	device struct
402  *
403  * Return: Always 0.
404  */
tpm_ibmvtpm_suspend(struct device * dev)405 static int tpm_ibmvtpm_suspend(struct device *dev)
406 {
407 	struct tpm_chip *chip = dev_get_drvdata(dev);
408 	struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev);
409 	int rc = 0;
410 
411 	rc = ibmvtpm_send_crq(ibmvtpm->vdev,
412 			IBMVTPM_VALID_CMD, VTPM_PREPARE_TO_SUSPEND, 0, 0);
413 	if (rc != H_SUCCESS)
414 		dev_err(ibmvtpm->dev,
415 			"tpm_ibmvtpm_suspend failed rc=%d\n", rc);
416 
417 	return rc;
418 }
419 
420 /**
421  * ibmvtpm_reset_crq - Reset CRQ
422  *
423  * @ibmvtpm:	ibm vtpm struct
424  *
425  * Return:
426  *	0 on success.
427  *	Non-zero on failure.
428  */
ibmvtpm_reset_crq(struct ibmvtpm_dev * ibmvtpm)429 static int ibmvtpm_reset_crq(struct ibmvtpm_dev *ibmvtpm)
430 {
431 	int rc = 0;
432 
433 	do {
434 		if (rc)
435 			msleep(100);
436 		rc = plpar_hcall_norets(H_FREE_CRQ,
437 					ibmvtpm->vdev->unit_address);
438 	} while (rc == H_BUSY || H_IS_LONG_BUSY(rc));
439 
440 	memset(ibmvtpm->crq_queue.crq_addr, 0, CRQ_RES_BUF_SIZE);
441 	ibmvtpm->crq_queue.index = 0;
442 
443 	return plpar_hcall_norets(H_REG_CRQ, ibmvtpm->vdev->unit_address,
444 				  ibmvtpm->crq_dma_handle, CRQ_RES_BUF_SIZE);
445 }
446 
tpm_ibmvtpm_req_canceled(struct tpm_chip * chip,u8 status)447 static bool tpm_ibmvtpm_req_canceled(struct tpm_chip *chip, u8 status)
448 {
449 	return (status == 0);
450 }
451 
452 static const struct tpm_class_ops tpm_ibmvtpm = {
453 	.recv = tpm_ibmvtpm_recv,
454 	.send = tpm_ibmvtpm_send,
455 	.cancel = tpm_ibmvtpm_cancel,
456 	.status = tpm_ibmvtpm_status,
457 	.req_complete_mask = 1,
458 	.req_complete_val = 0,
459 	.req_canceled = tpm_ibmvtpm_req_canceled,
460 };
461 
462 static const struct dev_pm_ops tpm_ibmvtpm_pm_ops = {
463 	.suspend = tpm_ibmvtpm_suspend,
464 	.resume = tpm_ibmvtpm_resume,
465 };
466 
467 /**
468  * ibmvtpm_crq_get_next - Get next responded crq
469  *
470  * @ibmvtpm:	vtpm device struct
471  *
472  * Return: vtpm crq pointer or NULL.
473  */
ibmvtpm_crq_get_next(struct ibmvtpm_dev * ibmvtpm)474 static struct ibmvtpm_crq *ibmvtpm_crq_get_next(struct ibmvtpm_dev *ibmvtpm)
475 {
476 	struct ibmvtpm_crq_queue *crq_q = &ibmvtpm->crq_queue;
477 	struct ibmvtpm_crq *crq = &crq_q->crq_addr[crq_q->index];
478 
479 	if (crq->valid & VTPM_MSG_RES) {
480 		if (++crq_q->index == crq_q->num_entry)
481 			crq_q->index = 0;
482 		smp_rmb();
483 	} else
484 		crq = NULL;
485 	return crq;
486 }
487 
488 /**
489  * ibmvtpm_crq_process - Process responded crq
490  *
491  * @crq:	crq to be processed
492  * @ibmvtpm:	vtpm device struct
493  *
494  */
ibmvtpm_crq_process(struct ibmvtpm_crq * crq,struct ibmvtpm_dev * ibmvtpm)495 static void ibmvtpm_crq_process(struct ibmvtpm_crq *crq,
496 				struct ibmvtpm_dev *ibmvtpm)
497 {
498 	int rc = 0;
499 
500 	switch (crq->valid) {
501 	case VALID_INIT_CRQ:
502 		switch (crq->msg) {
503 		case INIT_CRQ_RES:
504 			dev_info(ibmvtpm->dev, "CRQ initialized\n");
505 			rc = ibmvtpm_crq_send_init_complete(ibmvtpm);
506 			if (rc)
507 				dev_err(ibmvtpm->dev, "Unable to send CRQ init complete rc=%d\n", rc);
508 			return;
509 		case INIT_CRQ_COMP_RES:
510 			dev_info(ibmvtpm->dev,
511 				 "CRQ initialization completed\n");
512 			return;
513 		default:
514 			dev_err(ibmvtpm->dev, "Unknown crq message type: %d\n", crq->msg);
515 			return;
516 		}
517 	case IBMVTPM_VALID_CMD:
518 		switch (crq->msg) {
519 		case VTPM_GET_RTCE_BUFFER_SIZE_RES:
520 			if (be16_to_cpu(crq->len) <= 0) {
521 				dev_err(ibmvtpm->dev, "Invalid rtce size\n");
522 				return;
523 			}
524 			ibmvtpm->rtce_size = be16_to_cpu(crq->len);
525 			ibmvtpm->rtce_buf = kmalloc(ibmvtpm->rtce_size,
526 						    GFP_ATOMIC);
527 			if (!ibmvtpm->rtce_buf) {
528 				dev_err(ibmvtpm->dev, "Failed to allocate memory for rtce buffer\n");
529 				return;
530 			}
531 
532 			ibmvtpm->rtce_dma_handle = dma_map_single(ibmvtpm->dev,
533 				ibmvtpm->rtce_buf, ibmvtpm->rtce_size,
534 				DMA_BIDIRECTIONAL);
535 
536 			if (dma_mapping_error(ibmvtpm->dev,
537 					      ibmvtpm->rtce_dma_handle)) {
538 				kfree(ibmvtpm->rtce_buf);
539 				ibmvtpm->rtce_buf = NULL;
540 				dev_err(ibmvtpm->dev, "Failed to dma map rtce buffer\n");
541 			}
542 
543 			return;
544 		case VTPM_GET_VERSION_RES:
545 			ibmvtpm->vtpm_version = be32_to_cpu(crq->data);
546 			return;
547 		case VTPM_TPM_COMMAND_RES:
548 			/* len of the data in rtce buffer */
549 			ibmvtpm->res_len = be16_to_cpu(crq->len);
550 			ibmvtpm->tpm_processing_cmd = 0;
551 			wake_up_interruptible(&ibmvtpm->wq);
552 			return;
553 		default:
554 			return;
555 		}
556 	}
557 	return;
558 }
559 
560 /**
561  * ibmvtpm_interrupt -	Interrupt handler
562  *
563  * @irq:		irq number to handle
564  * @vtpm_instance:	vtpm that received interrupt
565  *
566  * Returns:
567  *	IRQ_HANDLED
568  **/
ibmvtpm_interrupt(int irq,void * vtpm_instance)569 static irqreturn_t ibmvtpm_interrupt(int irq, void *vtpm_instance)
570 {
571 	struct ibmvtpm_dev *ibmvtpm = (struct ibmvtpm_dev *) vtpm_instance;
572 	struct ibmvtpm_crq *crq;
573 
574 	/* while loop is needed for initial setup (get version and
575 	 * get rtce_size). There should be only one tpm request at any
576 	 * given time.
577 	 */
578 	while ((crq = ibmvtpm_crq_get_next(ibmvtpm)) != NULL) {
579 		ibmvtpm_crq_process(crq, ibmvtpm);
580 		wake_up_interruptible(&ibmvtpm->crq_queue.wq);
581 		crq->valid = 0;
582 		smp_wmb();
583 	}
584 
585 	return IRQ_HANDLED;
586 }
587 
588 /**
589  * tpm_ibmvtpm_probe - ibm vtpm initialize entry point
590  *
591  * @vio_dev:	vio device struct
592  * @id:		vio device id struct
593  *
594  * Return:
595  *	0 on success.
596  *	Non-zero on failure.
597  */
tpm_ibmvtpm_probe(struct vio_dev * vio_dev,const struct vio_device_id * id)598 static int tpm_ibmvtpm_probe(struct vio_dev *vio_dev,
599 				   const struct vio_device_id *id)
600 {
601 	struct ibmvtpm_dev *ibmvtpm;
602 	struct device *dev = &vio_dev->dev;
603 	struct ibmvtpm_crq_queue *crq_q;
604 	struct tpm_chip *chip;
605 	int rc = -ENOMEM, rc1;
606 
607 	chip = tpmm_chip_alloc(dev, &tpm_ibmvtpm);
608 	if (IS_ERR(chip))
609 		return PTR_ERR(chip);
610 
611 	ibmvtpm = kzalloc(sizeof(struct ibmvtpm_dev), GFP_KERNEL);
612 	if (!ibmvtpm) {
613 		dev_err(dev, "kzalloc for ibmvtpm failed\n");
614 		goto cleanup;
615 	}
616 
617 	ibmvtpm->dev = dev;
618 	ibmvtpm->vdev = vio_dev;
619 
620 	crq_q = &ibmvtpm->crq_queue;
621 	crq_q->crq_addr = (struct ibmvtpm_crq *)get_zeroed_page(GFP_KERNEL);
622 	if (!crq_q->crq_addr) {
623 		dev_err(dev, "Unable to allocate memory for crq_addr\n");
624 		goto cleanup;
625 	}
626 
627 	crq_q->num_entry = CRQ_RES_BUF_SIZE / sizeof(*crq_q->crq_addr);
628 	init_waitqueue_head(&crq_q->wq);
629 	ibmvtpm->crq_dma_handle = dma_map_single(dev, crq_q->crq_addr,
630 						 CRQ_RES_BUF_SIZE,
631 						 DMA_BIDIRECTIONAL);
632 
633 	if (dma_mapping_error(dev, ibmvtpm->crq_dma_handle)) {
634 		dev_err(dev, "dma mapping failed\n");
635 		goto cleanup;
636 	}
637 
638 	rc = plpar_hcall_norets(H_REG_CRQ, vio_dev->unit_address,
639 				ibmvtpm->crq_dma_handle, CRQ_RES_BUF_SIZE);
640 	if (rc == H_RESOURCE)
641 		rc = ibmvtpm_reset_crq(ibmvtpm);
642 
643 	if (rc) {
644 		dev_err(dev, "Unable to register CRQ rc=%d\n", rc);
645 		goto reg_crq_cleanup;
646 	}
647 
648 	rc = request_irq(vio_dev->irq, ibmvtpm_interrupt, 0,
649 			 tpm_ibmvtpm_driver_name, ibmvtpm);
650 	if (rc) {
651 		dev_err(dev, "Error %d register irq 0x%x\n", rc, vio_dev->irq);
652 		goto init_irq_cleanup;
653 	}
654 
655 	rc = vio_enable_interrupts(vio_dev);
656 	if (rc) {
657 		dev_err(dev, "Error %d enabling interrupts\n", rc);
658 		goto init_irq_cleanup;
659 	}
660 
661 	init_waitqueue_head(&ibmvtpm->wq);
662 
663 	crq_q->index = 0;
664 
665 	dev_set_drvdata(&chip->dev, ibmvtpm);
666 
667 	spin_lock_init(&ibmvtpm->rtce_lock);
668 
669 	rc = ibmvtpm_crq_send_init(ibmvtpm);
670 	if (rc)
671 		goto init_irq_cleanup;
672 
673 	rc = ibmvtpm_crq_get_version(ibmvtpm);
674 	if (rc)
675 		goto init_irq_cleanup;
676 
677 	rc = ibmvtpm_crq_get_rtce_size(ibmvtpm);
678 	if (rc)
679 		goto init_irq_cleanup;
680 
681 	if (!wait_event_timeout(ibmvtpm->crq_queue.wq,
682 				ibmvtpm->rtce_buf != NULL,
683 				HZ)) {
684 		rc = -ENODEV;
685 		dev_err(dev, "CRQ response timed out\n");
686 		goto init_irq_cleanup;
687 	}
688 
689 
690 	if (!strcmp(id->compat, "IBM,vtpm20"))
691 		chip->flags |= TPM_CHIP_FLAG_TPM2;
692 
693 	rc = tpm_get_timeouts(chip);
694 	if (rc)
695 		goto init_irq_cleanup;
696 
697 	if (chip->flags & TPM_CHIP_FLAG_TPM2) {
698 		rc = tpm2_get_cc_attrs_tbl(chip);
699 		if (rc)
700 			goto init_irq_cleanup;
701 
702 		rc = tpm2_sessions_init(chip);
703 		if (rc)
704 			goto init_irq_cleanup;
705 	}
706 
707 	return tpm_chip_register(chip);
708 init_irq_cleanup:
709 	do {
710 		rc1 = plpar_hcall_norets(H_FREE_CRQ, vio_dev->unit_address);
711 	} while (rc1 == H_BUSY || H_IS_LONG_BUSY(rc1));
712 reg_crq_cleanup:
713 	dma_unmap_single(dev, ibmvtpm->crq_dma_handle, CRQ_RES_BUF_SIZE,
714 			 DMA_BIDIRECTIONAL);
715 cleanup:
716 	if (ibmvtpm) {
717 		if (crq_q->crq_addr)
718 			free_page((unsigned long)crq_q->crq_addr);
719 		kfree(ibmvtpm);
720 	}
721 
722 	return rc;
723 }
724 
725 static struct vio_driver ibmvtpm_driver = {
726 	.id_table	 = tpm_ibmvtpm_device_table,
727 	.probe		 = tpm_ibmvtpm_probe,
728 	.remove		 = tpm_ibmvtpm_remove,
729 	.get_desired_dma = tpm_ibmvtpm_get_desired_dma,
730 	.name		 = tpm_ibmvtpm_driver_name,
731 	.pm		 = &tpm_ibmvtpm_pm_ops,
732 };
733 
734 /**
735  * ibmvtpm_module_init - Initialize ibm vtpm module.
736  *
737  *
738  * Return:
739  *	0 on success.
740  *	Non-zero on failure.
741  */
ibmvtpm_module_init(void)742 static int __init ibmvtpm_module_init(void)
743 {
744 	return vio_register_driver(&ibmvtpm_driver);
745 }
746 
747 /**
748  * ibmvtpm_module_exit - Tear down ibm vtpm module.
749  */
ibmvtpm_module_exit(void)750 static void __exit ibmvtpm_module_exit(void)
751 {
752 	vio_unregister_driver(&ibmvtpm_driver);
753 }
754 
755 module_init(ibmvtpm_module_init);
756 module_exit(ibmvtpm_module_exit);
757 
758 MODULE_AUTHOR("adlai@us.ibm.com");
759 MODULE_DESCRIPTION("IBM vTPM Driver");
760 MODULE_VERSION("1.0");
761 MODULE_LICENSE("GPL");
762