tpm_ibmvtpm.c

  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
 28static const char tpm_ibmvtpm_driver_name[] = "tpm_ibmvtpm";
 29
 30static const struct vio_device_id tpm_ibmvtpm_device_table[] = {
 31	{ "IBM,vtpm", "IBM,vtpm"},
 32	{ "IBM,vtpm", "IBM,vtpm20"},
 33	{ "", "" }
 34};
 35MODULE_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 */
 46static 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 */
 87static 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 */
105static 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 */
140static 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 */
159static 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 * @bufsiz:	size of the buffer
195 * @count:	length of the command
196 *
197 * Return:
198 *   0 on success,
199 *   -errno on error
200 */
201static int tpm_ibmvtpm_send(struct tpm_chip *chip, u8 *buf, size_t bufsiz,
202			    size_t count)
203{
204	struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev);
205	bool retry = true;
206	int rc, sig;
207
208	if (!ibmvtpm->rtce_buf) {
209		dev_err(ibmvtpm->dev, "ibmvtpm device is not ready\n");
210		return 0;
211	}
212
213	if (count > ibmvtpm->rtce_size) {
214		dev_err(ibmvtpm->dev,
215			"Invalid size in send: count=%zd, rtce_size=%d\n",
216			count, ibmvtpm->rtce_size);
217		return -EIO;
218	}
219
220	if (ibmvtpm->tpm_processing_cmd) {
221		dev_info(ibmvtpm->dev,
222		         "Need to wait for TPM to finish\n");
223		/* wait for previous command to finish */
224		sig = wait_event_interruptible(ibmvtpm->wq, !ibmvtpm->tpm_processing_cmd);
225		if (sig)
226			return -EINTR;
227	}
228
229	spin_lock(&ibmvtpm->rtce_lock);
230	ibmvtpm->res_len = 0;
231	memcpy((void *)ibmvtpm->rtce_buf, (void *)buf, count);
232
233	/*
234	 * set the processing flag before the Hcall, since we may get the
235	 * result (interrupt) before even being able to check rc.
236	 */
237	ibmvtpm->tpm_processing_cmd = 1;
238
239again:
240	rc = ibmvtpm_send_crq(ibmvtpm->vdev,
241			IBMVTPM_VALID_CMD, VTPM_TPM_COMMAND,
242			count, ibmvtpm->rtce_dma_handle);
243	if (rc != H_SUCCESS) {
244		/*
245		 * H_CLOSED can be returned after LPM resume.  Call
246		 * tpm_ibmvtpm_resume() to re-enable the CRQ then retry
247		 * ibmvtpm_send_crq() once before failing.
248		 */
249		if (rc == H_CLOSED && retry) {
250			tpm_ibmvtpm_resume(ibmvtpm->dev);
251			retry = false;
252			goto again;
253		}
254		dev_err(ibmvtpm->dev, "tpm_ibmvtpm_send failed rc=%d\n", rc);
255		ibmvtpm->tpm_processing_cmd = 0;
256	}
257
258	spin_unlock(&ibmvtpm->rtce_lock);
259	return 0;
260}
261
262static void tpm_ibmvtpm_cancel(struct tpm_chip *chip)
263{
264	return;
265}
266
267static u8 tpm_ibmvtpm_status(struct tpm_chip *chip)
268{
269	struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev);
270
271	return ibmvtpm->tpm_processing_cmd;
272}
273
274/**
275 * ibmvtpm_crq_get_rtce_size - Send a CRQ request to get rtce size
276 *
277 * @ibmvtpm:	vtpm device struct
278 *
279 * Return:
280 *	0 on success.
281 *	Non-zero on failure.
282 */
283static int ibmvtpm_crq_get_rtce_size(struct ibmvtpm_dev *ibmvtpm)
284{
285	int rc;
286
287	rc = ibmvtpm_send_crq(ibmvtpm->vdev,
288			IBMVTPM_VALID_CMD, VTPM_GET_RTCE_BUFFER_SIZE, 0, 0);
289	if (rc != H_SUCCESS)
290		dev_err(ibmvtpm->dev,
291			"ibmvtpm_crq_get_rtce_size failed rc=%d\n", rc);
292
293	return rc;
294}
295
296/**
297 * ibmvtpm_crq_get_version - Send a CRQ request to get vtpm version
298 *			   - Note that this is vtpm version and not tpm version
299 *
300 * @ibmvtpm:	vtpm device struct
301 *
302 * Return:
303 *	0 on success.
304 *	Non-zero on failure.
305 */
306static int ibmvtpm_crq_get_version(struct ibmvtpm_dev *ibmvtpm)
307{
308	int rc;
309
310	rc = ibmvtpm_send_crq(ibmvtpm->vdev,
311			IBMVTPM_VALID_CMD, VTPM_GET_VERSION, 0, 0);
312	if (rc != H_SUCCESS)
313		dev_err(ibmvtpm->dev,
314			"ibmvtpm_crq_get_version failed rc=%d\n", rc);
315
316	return rc;
317}
318
319/**
320 * ibmvtpm_crq_send_init_complete - Send a CRQ initialize complete message
321 * @ibmvtpm:	vtpm device struct
322 *
323 * Return:
324 *	0 on success.
325 *	Non-zero on failure.
326 */
327static int ibmvtpm_crq_send_init_complete(struct ibmvtpm_dev *ibmvtpm)
328{
329	int rc;
330
331	rc = ibmvtpm_send_crq_word(ibmvtpm->vdev, INIT_CRQ_COMP_CMD);
332	if (rc != H_SUCCESS)
333		dev_err(ibmvtpm->dev,
334			"ibmvtpm_crq_send_init_complete failed rc=%d\n", rc);
335
336	return rc;
337}
338
339/**
340 * tpm_ibmvtpm_remove - ibm vtpm remove entry point
341 * @vdev:	vio device struct
342 *
343 * Return: Always 0.
344 */
345static void tpm_ibmvtpm_remove(struct vio_dev *vdev)
346{
347	struct tpm_chip *chip = dev_get_drvdata(&vdev->dev);
348	struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev);
349	int rc = 0;
350
351	tpm_chip_unregister(chip);
352
353	free_irq(vdev->irq, ibmvtpm);
354
355	do {
356		if (rc)
357			msleep(100);
358		rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
359	} while (rc == H_BUSY || H_IS_LONG_BUSY(rc));
360
361	dma_unmap_single(ibmvtpm->dev, ibmvtpm->crq_dma_handle,
362			 CRQ_RES_BUF_SIZE, DMA_BIDIRECTIONAL);
363	free_page((unsigned long)ibmvtpm->crq_queue.crq_addr);
364
365	if (ibmvtpm->rtce_buf) {
366		dma_unmap_single(ibmvtpm->dev, ibmvtpm->rtce_dma_handle,
367				 ibmvtpm->rtce_size, DMA_BIDIRECTIONAL);
368		kfree(ibmvtpm->rtce_buf);
369	}
370
371	kfree(ibmvtpm);
372	/* For tpm_ibmvtpm_get_desired_dma */
373	dev_set_drvdata(&vdev->dev, NULL);
374}
375
376/**
377 * tpm_ibmvtpm_get_desired_dma - Get DMA size needed by this driver
378 * @vdev:	vio device struct
379 *
380 * Return:
381 *	Number of bytes the driver needs to DMA map.
382 */
383static unsigned long tpm_ibmvtpm_get_desired_dma(struct vio_dev *vdev)
384{
385	struct tpm_chip *chip = dev_get_drvdata(&vdev->dev);
386	struct ibmvtpm_dev *ibmvtpm;
387
388	/*
389	 * ibmvtpm initializes at probe time, so the data we are
390	 * asking for may not be set yet. Estimate that 4K required
391	 * for TCE-mapped buffer in addition to CRQ.
392	 */
393	if (chip)
394		ibmvtpm = dev_get_drvdata(&chip->dev);
395	else
396		return CRQ_RES_BUF_SIZE + PAGE_SIZE;
397
398	return CRQ_RES_BUF_SIZE + ibmvtpm->rtce_size;
399}
400
401/**
402 * tpm_ibmvtpm_suspend - Suspend
403 * @dev:	device struct
404 *
405 * Return: Always 0.
406 */
407static int tpm_ibmvtpm_suspend(struct device *dev)
408{
409	struct tpm_chip *chip = dev_get_drvdata(dev);
410	struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev);
411	int rc = 0;
412
413	rc = ibmvtpm_send_crq(ibmvtpm->vdev,
414			IBMVTPM_VALID_CMD, VTPM_PREPARE_TO_SUSPEND, 0, 0);
415	if (rc != H_SUCCESS)
416		dev_err(ibmvtpm->dev,
417			"tpm_ibmvtpm_suspend failed rc=%d\n", rc);
418
419	return rc;
420}
421
422/**
423 * ibmvtpm_reset_crq - Reset CRQ
424 *
425 * @ibmvtpm:	ibm vtpm struct
426 *
427 * Return:
428 *	0 on success.
429 *	Non-zero on failure.
430 */
431static int ibmvtpm_reset_crq(struct ibmvtpm_dev *ibmvtpm)
432{
433	int rc = 0;
434
435	do {
436		if (rc)
437			msleep(100);
438		rc = plpar_hcall_norets(H_FREE_CRQ,
439					ibmvtpm->vdev->unit_address);
440	} while (rc == H_BUSY || H_IS_LONG_BUSY(rc));
441
442	memset(ibmvtpm->crq_queue.crq_addr, 0, CRQ_RES_BUF_SIZE);
443	ibmvtpm->crq_queue.index = 0;
444
445	return plpar_hcall_norets(H_REG_CRQ, ibmvtpm->vdev->unit_address,
446				  ibmvtpm->crq_dma_handle, CRQ_RES_BUF_SIZE);
447}
448
449static bool tpm_ibmvtpm_req_canceled(struct tpm_chip *chip, u8 status)
450{
451	return (status == 0);
452}
453
454static const struct tpm_class_ops tpm_ibmvtpm = {
455	.flags = TPM_OPS_AUTO_STARTUP,
456	.recv = tpm_ibmvtpm_recv,
457	.send = tpm_ibmvtpm_send,
458	.cancel = tpm_ibmvtpm_cancel,
459	.status = tpm_ibmvtpm_status,
460	.req_complete_mask = 1,
461	.req_complete_val = 0,
462	.req_canceled = tpm_ibmvtpm_req_canceled,
463};
464
465static 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 */
477static 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 */
498static 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 = 0;
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 **/
572static 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 */
601static 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		rc = -ENODEV;
688		dev_err(dev, "CRQ response timed out\n");
689		goto init_irq_cleanup;
690	}
691
692
693	if (!strcmp(id->compat, "IBM,vtpm20"))
694		chip->flags |= TPM_CHIP_FLAG_TPM2;
695
696	return tpm_chip_register(chip);
697init_irq_cleanup:
698	do {
699		rc1 = plpar_hcall_norets(H_FREE_CRQ, vio_dev->unit_address);
700	} while (rc1 == H_BUSY || H_IS_LONG_BUSY(rc1));
701reg_crq_cleanup:
702	dma_unmap_single(dev, ibmvtpm->crq_dma_handle, CRQ_RES_BUF_SIZE,
703			 DMA_BIDIRECTIONAL);
704cleanup:
705	if (ibmvtpm) {
706		if (crq_q->crq_addr)
707			free_page((unsigned long)crq_q->crq_addr);
708		kfree(ibmvtpm);
709	}
710
711	return rc;
712}
713
714static struct vio_driver ibmvtpm_driver = {
715	.id_table	 = tpm_ibmvtpm_device_table,
716	.probe		 = tpm_ibmvtpm_probe,
717	.remove		 = tpm_ibmvtpm_remove,
718	.get_desired_dma = tpm_ibmvtpm_get_desired_dma,
719	.name		 = tpm_ibmvtpm_driver_name,
720	.pm		 = &tpm_ibmvtpm_pm_ops,
721};
722
723/**
724 * ibmvtpm_module_init - Initialize ibm vtpm module.
725 *
726 *
727 * Return:
728 *	0 on success.
729 *	Non-zero on failure.
730 */
731static int __init ibmvtpm_module_init(void)
732{
733	return vio_register_driver(&ibmvtpm_driver);
734}
735
736/**
737 * ibmvtpm_module_exit - Tear down ibm vtpm module.
738 */
739static void __exit ibmvtpm_module_exit(void)
740{
741	vio_unregister_driver(&ibmvtpm_driver);
742}
743
744module_init(ibmvtpm_module_init);
745module_exit(ibmvtpm_module_exit);
746
747MODULE_AUTHOR("adlai@us.ibm.com");
748MODULE_DESCRIPTION("IBM vTPM Driver");
749MODULE_VERSION("1.0");
750MODULE_LICENSE("GPL");