2 * Copyright (C) 2012 IBM Corporation
4 * Author: Ashley Lai <ashleydlai@gmail.com>
6 * Maintained by: <tpmdd-devel@lists.sourceforge.net>
8 * Device driver for TCG/TCPA TPM (trusted platform module).
9 * Specifications at www.trustedcomputinggroup.org
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public License as
13 * published by the Free Software Foundation, version 2 of the
18 #include <linux/dma-mapping.h>
19 #include <linux/dmapool.h>
20 #include <linux/slab.h>
23 #include <linux/types.h>
24 #include <linux/list.h>
25 #include <linux/spinlock.h>
26 #include <linux/interrupt.h>
27 #include <linux/wait.h>
31 #include "tpm_ibmvtpm.h"
33 static const char tpm_ibmvtpm_driver_name[] = "tpm_ibmvtpm";
35 static struct vio_device_id tpm_ibmvtpm_device_table[] = {
36 { "IBM,vtpm", "IBM,vtpm"},
39 MODULE_DEVICE_TABLE(vio, tpm_ibmvtpm_device_table);
42 * ibmvtpm_send_crq - Send a CRQ request
43 * @vdev: vio device struct
51 static int ibmvtpm_send_crq(struct vio_dev *vdev, u64 w1, u64 w2)
53 return plpar_hcall_norets(H_SEND_CRQ, vdev->unit_address, w1, w2);
57 * ibmvtpm_get_data - Retrieve ibm vtpm data
63 static struct ibmvtpm_dev *ibmvtpm_get_data(const struct device *dev)
65 struct tpm_chip *chip = dev_get_drvdata(dev);
67 return (struct ibmvtpm_dev *)TPM_VPRIV(chip);
72 * tpm_ibmvtpm_recv - Receive data after send
73 * @chip: tpm chip struct
74 * @buf: buffer to read
75 * count: size of buffer
78 * Number of bytes read
80 static int tpm_ibmvtpm_recv(struct tpm_chip *chip, u8 *buf, size_t count)
82 struct ibmvtpm_dev *ibmvtpm;
86 ibmvtpm = (struct ibmvtpm_dev *)TPM_VPRIV(chip);
88 if (!ibmvtpm->rtce_buf) {
89 dev_err(ibmvtpm->dev, "ibmvtpm device is not ready\n");
93 sig = wait_event_interruptible(ibmvtpm->wq, ibmvtpm->res_len != 0);
97 len = ibmvtpm->res_len;
100 dev_err(ibmvtpm->dev,
101 "Invalid size in recv: count=%zd, crq_size=%d\n",
106 spin_lock(&ibmvtpm->rtce_lock);
107 memcpy((void *)buf, (void *)ibmvtpm->rtce_buf, len);
108 memset(ibmvtpm->rtce_buf, 0, len);
109 ibmvtpm->res_len = 0;
110 spin_unlock(&ibmvtpm->rtce_lock);
115 * tpm_ibmvtpm_send - Send tpm request
116 * @chip: tpm chip struct
117 * @buf: buffer contains data to send
118 * count: size of buffer
121 * Number of bytes sent
123 static int tpm_ibmvtpm_send(struct tpm_chip *chip, u8 *buf, size_t count)
125 struct ibmvtpm_dev *ibmvtpm;
126 struct ibmvtpm_crq crq;
127 u64 *word = (u64 *) &crq;
130 ibmvtpm = (struct ibmvtpm_dev *)TPM_VPRIV(chip);
132 if (!ibmvtpm->rtce_buf) {
133 dev_err(ibmvtpm->dev, "ibmvtpm device is not ready\n");
137 if (count > ibmvtpm->rtce_size) {
138 dev_err(ibmvtpm->dev,
139 "Invalid size in send: count=%zd, rtce_size=%d\n",
140 count, ibmvtpm->rtce_size);
144 spin_lock(&ibmvtpm->rtce_lock);
145 memcpy((void *)ibmvtpm->rtce_buf, (void *)buf, count);
146 crq.valid = (u8)IBMVTPM_VALID_CMD;
147 crq.msg = (u8)VTPM_TPM_COMMAND;
148 crq.len = (u16)count;
149 crq.data = ibmvtpm->rtce_dma_handle;
151 rc = ibmvtpm_send_crq(ibmvtpm->vdev, word[0], word[1]);
152 if (rc != H_SUCCESS) {
153 dev_err(ibmvtpm->dev, "tpm_ibmvtpm_send failed rc=%d\n", rc);
158 spin_unlock(&ibmvtpm->rtce_lock);
162 static void tpm_ibmvtpm_cancel(struct tpm_chip *chip)
167 static u8 tpm_ibmvtpm_status(struct tpm_chip *chip)
173 * ibmvtpm_crq_get_rtce_size - Send a CRQ request to get rtce size
174 * @ibmvtpm: vtpm device struct
180 static int ibmvtpm_crq_get_rtce_size(struct ibmvtpm_dev *ibmvtpm)
182 struct ibmvtpm_crq crq;
183 u64 *buf = (u64 *) &crq;
186 crq.valid = (u8)IBMVTPM_VALID_CMD;
187 crq.msg = (u8)VTPM_GET_RTCE_BUFFER_SIZE;
189 rc = ibmvtpm_send_crq(ibmvtpm->vdev, buf[0], buf[1]);
191 dev_err(ibmvtpm->dev,
192 "ibmvtpm_crq_get_rtce_size failed rc=%d\n", rc);
198 * ibmvtpm_crq_get_version - Send a CRQ request to get vtpm version
199 * - Note that this is vtpm version and not tpm version
200 * @ibmvtpm: vtpm device struct
206 static int ibmvtpm_crq_get_version(struct ibmvtpm_dev *ibmvtpm)
208 struct ibmvtpm_crq crq;
209 u64 *buf = (u64 *) &crq;
212 crq.valid = (u8)IBMVTPM_VALID_CMD;
213 crq.msg = (u8)VTPM_GET_VERSION;
215 rc = ibmvtpm_send_crq(ibmvtpm->vdev, buf[0], buf[1]);
217 dev_err(ibmvtpm->dev,
218 "ibmvtpm_crq_get_version failed rc=%d\n", rc);
224 * ibmvtpm_crq_send_init_complete - Send a CRQ initialize complete message
225 * @ibmvtpm: vtpm device struct
231 static int ibmvtpm_crq_send_init_complete(struct ibmvtpm_dev *ibmvtpm)
235 rc = ibmvtpm_send_crq(ibmvtpm->vdev, INIT_CRQ_COMP_CMD, 0);
237 dev_err(ibmvtpm->dev,
238 "ibmvtpm_crq_send_init_complete failed rc=%d\n", rc);
244 * ibmvtpm_crq_send_init - Send a CRQ initialize message
245 * @ibmvtpm: vtpm device struct
251 static int ibmvtpm_crq_send_init(struct ibmvtpm_dev *ibmvtpm)
255 rc = ibmvtpm_send_crq(ibmvtpm->vdev, INIT_CRQ_CMD, 0);
257 dev_err(ibmvtpm->dev,
258 "ibmvtpm_crq_send_init failed rc=%d\n", rc);
264 * tpm_ibmvtpm_remove - ibm vtpm remove entry point
265 * @vdev: vio device struct
270 static int tpm_ibmvtpm_remove(struct vio_dev *vdev)
272 struct ibmvtpm_dev *ibmvtpm = ibmvtpm_get_data(&vdev->dev);
273 struct tpm_chip *chip = dev_get_drvdata(ibmvtpm->dev);
276 tpm_chip_unregister(chip);
278 free_irq(vdev->irq, ibmvtpm);
283 rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
284 } while (rc == H_BUSY || H_IS_LONG_BUSY(rc));
286 dma_unmap_single(ibmvtpm->dev, ibmvtpm->crq_dma_handle,
287 CRQ_RES_BUF_SIZE, DMA_BIDIRECTIONAL);
288 free_page((unsigned long)ibmvtpm->crq_queue.crq_addr);
290 if (ibmvtpm->rtce_buf) {
291 dma_unmap_single(ibmvtpm->dev, ibmvtpm->rtce_dma_handle,
292 ibmvtpm->rtce_size, DMA_BIDIRECTIONAL);
293 kfree(ibmvtpm->rtce_buf);
302 * tpm_ibmvtpm_get_desired_dma - Get DMA size needed by this driver
303 * @vdev: vio device struct
306 * Number of bytes the driver needs to DMA map
308 static unsigned long tpm_ibmvtpm_get_desired_dma(struct vio_dev *vdev)
310 struct ibmvtpm_dev *ibmvtpm = ibmvtpm_get_data(&vdev->dev);
312 /* ibmvtpm initializes at probe time, so the data we are
313 * asking for may not be set yet. Estimate that 4K required
314 * for TCE-mapped buffer in addition to CRQ.
317 return CRQ_RES_BUF_SIZE + PAGE_SIZE;
319 return CRQ_RES_BUF_SIZE + ibmvtpm->rtce_size;
323 * tpm_ibmvtpm_suspend - Suspend
324 * @dev: device struct
329 static int tpm_ibmvtpm_suspend(struct device *dev)
331 struct ibmvtpm_dev *ibmvtpm = ibmvtpm_get_data(dev);
332 struct ibmvtpm_crq crq;
333 u64 *buf = (u64 *) &crq;
336 crq.valid = (u8)IBMVTPM_VALID_CMD;
337 crq.msg = (u8)VTPM_PREPARE_TO_SUSPEND;
339 rc = ibmvtpm_send_crq(ibmvtpm->vdev, buf[0], buf[1]);
341 dev_err(ibmvtpm->dev,
342 "tpm_ibmvtpm_suspend failed rc=%d\n", rc);
348 * ibmvtpm_reset_crq - Reset CRQ
349 * @ibmvtpm: ibm vtpm struct
355 static int ibmvtpm_reset_crq(struct ibmvtpm_dev *ibmvtpm)
362 rc = plpar_hcall_norets(H_FREE_CRQ,
363 ibmvtpm->vdev->unit_address);
364 } while (rc == H_BUSY || H_IS_LONG_BUSY(rc));
366 memset(ibmvtpm->crq_queue.crq_addr, 0, CRQ_RES_BUF_SIZE);
367 ibmvtpm->crq_queue.index = 0;
369 return plpar_hcall_norets(H_REG_CRQ, ibmvtpm->vdev->unit_address,
370 ibmvtpm->crq_dma_handle, CRQ_RES_BUF_SIZE);
374 * tpm_ibmvtpm_resume - Resume from suspend
375 * @dev: device struct
380 static int tpm_ibmvtpm_resume(struct device *dev)
382 struct ibmvtpm_dev *ibmvtpm = ibmvtpm_get_data(dev);
388 rc = plpar_hcall_norets(H_ENABLE_CRQ,
389 ibmvtpm->vdev->unit_address);
390 } while (rc == H_IN_PROGRESS || rc == H_BUSY || H_IS_LONG_BUSY(rc));
393 dev_err(dev, "Error enabling ibmvtpm rc=%d\n", rc);
397 rc = vio_enable_interrupts(ibmvtpm->vdev);
399 dev_err(dev, "Error vio_enable_interrupts rc=%d\n", rc);
403 rc = ibmvtpm_crq_send_init(ibmvtpm);
405 dev_err(dev, "Error send_init rc=%d\n", rc);
410 static bool tpm_ibmvtpm_req_canceled(struct tpm_chip *chip, u8 status)
412 return (status == 0);
415 static const struct tpm_class_ops tpm_ibmvtpm = {
416 .recv = tpm_ibmvtpm_recv,
417 .send = tpm_ibmvtpm_send,
418 .cancel = tpm_ibmvtpm_cancel,
419 .status = tpm_ibmvtpm_status,
420 .req_complete_mask = 0,
421 .req_complete_val = 0,
422 .req_canceled = tpm_ibmvtpm_req_canceled,
425 static const struct dev_pm_ops tpm_ibmvtpm_pm_ops = {
426 .suspend = tpm_ibmvtpm_suspend,
427 .resume = tpm_ibmvtpm_resume,
431 * ibmvtpm_crq_get_next - Get next responded crq
432 * @ibmvtpm vtpm device struct
437 static struct ibmvtpm_crq *ibmvtpm_crq_get_next(struct ibmvtpm_dev *ibmvtpm)
439 struct ibmvtpm_crq_queue *crq_q = &ibmvtpm->crq_queue;
440 struct ibmvtpm_crq *crq = &crq_q->crq_addr[crq_q->index];
442 if (crq->valid & VTPM_MSG_RES) {
443 if (++crq_q->index == crq_q->num_entry)
452 * ibmvtpm_crq_process - Process responded crq
453 * @crq crq to be processed
454 * @ibmvtpm vtpm device struct
459 static void ibmvtpm_crq_process(struct ibmvtpm_crq *crq,
460 struct ibmvtpm_dev *ibmvtpm)
464 switch (crq->valid) {
468 dev_info(ibmvtpm->dev, "CRQ initialized\n");
469 rc = ibmvtpm_crq_send_init_complete(ibmvtpm);
471 dev_err(ibmvtpm->dev, "Unable to send CRQ init complete rc=%d\n", rc);
473 case INIT_CRQ_COMP_RES:
474 dev_info(ibmvtpm->dev,
475 "CRQ initialization completed\n");
478 dev_err(ibmvtpm->dev, "Unknown crq message type: %d\n", crq->msg);
481 case IBMVTPM_VALID_CMD:
483 case VTPM_GET_RTCE_BUFFER_SIZE_RES:
485 dev_err(ibmvtpm->dev, "Invalid rtce size\n");
488 ibmvtpm->rtce_size = crq->len;
489 ibmvtpm->rtce_buf = kmalloc(ibmvtpm->rtce_size,
491 if (!ibmvtpm->rtce_buf) {
492 dev_err(ibmvtpm->dev, "Failed to allocate memory for rtce buffer\n");
496 ibmvtpm->rtce_dma_handle = dma_map_single(ibmvtpm->dev,
497 ibmvtpm->rtce_buf, ibmvtpm->rtce_size,
500 if (dma_mapping_error(ibmvtpm->dev,
501 ibmvtpm->rtce_dma_handle)) {
502 kfree(ibmvtpm->rtce_buf);
503 ibmvtpm->rtce_buf = NULL;
504 dev_err(ibmvtpm->dev, "Failed to dma map rtce buffer\n");
508 case VTPM_GET_VERSION_RES:
509 ibmvtpm->vtpm_version = crq->data;
511 case VTPM_TPM_COMMAND_RES:
512 /* len of the data in rtce buffer */
513 ibmvtpm->res_len = crq->len;
514 wake_up_interruptible(&ibmvtpm->wq);
524 * ibmvtpm_interrupt - Interrupt handler
525 * @irq: irq number to handle
526 * @vtpm_instance: vtpm that received interrupt
531 static irqreturn_t ibmvtpm_interrupt(int irq, void *vtpm_instance)
533 struct ibmvtpm_dev *ibmvtpm = (struct ibmvtpm_dev *) vtpm_instance;
534 struct ibmvtpm_crq *crq;
536 /* while loop is needed for initial setup (get version and
537 * get rtce_size). There should be only one tpm request at any
540 while ((crq = ibmvtpm_crq_get_next(ibmvtpm)) != NULL) {
541 ibmvtpm_crq_process(crq, ibmvtpm);
550 * tpm_ibmvtpm_probe - ibm vtpm initialize entry point
551 * @vio_dev: vio device struct
552 * @id: vio device id struct
558 static int tpm_ibmvtpm_probe(struct vio_dev *vio_dev,
559 const struct vio_device_id *id)
561 struct ibmvtpm_dev *ibmvtpm;
562 struct device *dev = &vio_dev->dev;
563 struct ibmvtpm_crq_queue *crq_q;
564 struct tpm_chip *chip;
565 int rc = -ENOMEM, rc1;
567 chip = tpmm_chip_alloc(dev, &tpm_ibmvtpm);
569 return PTR_ERR(chip);
571 ibmvtpm = kzalloc(sizeof(struct ibmvtpm_dev), GFP_KERNEL);
573 dev_err(dev, "kzalloc for ibmvtpm failed\n");
577 crq_q = &ibmvtpm->crq_queue;
578 crq_q->crq_addr = (struct ibmvtpm_crq *)get_zeroed_page(GFP_KERNEL);
579 if (!crq_q->crq_addr) {
580 dev_err(dev, "Unable to allocate memory for crq_addr\n");
584 crq_q->num_entry = CRQ_RES_BUF_SIZE / sizeof(*crq_q->crq_addr);
585 ibmvtpm->crq_dma_handle = dma_map_single(dev, crq_q->crq_addr,
589 if (dma_mapping_error(dev, ibmvtpm->crq_dma_handle)) {
590 dev_err(dev, "dma mapping failed\n");
594 rc = plpar_hcall_norets(H_REG_CRQ, vio_dev->unit_address,
595 ibmvtpm->crq_dma_handle, CRQ_RES_BUF_SIZE);
596 if (rc == H_RESOURCE)
597 rc = ibmvtpm_reset_crq(ibmvtpm);
600 dev_err(dev, "Unable to register CRQ rc=%d\n", rc);
601 goto reg_crq_cleanup;
604 rc = request_irq(vio_dev->irq, ibmvtpm_interrupt, 0,
605 tpm_ibmvtpm_driver_name, ibmvtpm);
607 dev_err(dev, "Error %d register irq 0x%x\n", rc, vio_dev->irq);
608 goto init_irq_cleanup;
611 rc = vio_enable_interrupts(vio_dev);
613 dev_err(dev, "Error %d enabling interrupts\n", rc);
614 goto init_irq_cleanup;
617 init_waitqueue_head(&ibmvtpm->wq);
622 ibmvtpm->vdev = vio_dev;
623 TPM_VPRIV(chip) = (void *)ibmvtpm;
625 spin_lock_init(&ibmvtpm->rtce_lock);
627 rc = ibmvtpm_crq_send_init(ibmvtpm);
629 goto init_irq_cleanup;
631 rc = ibmvtpm_crq_get_version(ibmvtpm);
633 goto init_irq_cleanup;
635 rc = ibmvtpm_crq_get_rtce_size(ibmvtpm);
637 goto init_irq_cleanup;
639 return tpm_chip_register(chip);
642 rc1 = plpar_hcall_norets(H_FREE_CRQ, vio_dev->unit_address);
643 } while (rc1 == H_BUSY || H_IS_LONG_BUSY(rc1));
645 dma_unmap_single(dev, ibmvtpm->crq_dma_handle, CRQ_RES_BUF_SIZE,
650 free_page((unsigned long)crq_q->crq_addr);
657 static struct vio_driver ibmvtpm_driver = {
658 .id_table = tpm_ibmvtpm_device_table,
659 .probe = tpm_ibmvtpm_probe,
660 .remove = tpm_ibmvtpm_remove,
661 .get_desired_dma = tpm_ibmvtpm_get_desired_dma,
662 .name = tpm_ibmvtpm_driver_name,
663 .pm = &tpm_ibmvtpm_pm_ops,
667 * ibmvtpm_module_init - Initialize ibm vtpm module
673 static int __init ibmvtpm_module_init(void)
675 return vio_register_driver(&ibmvtpm_driver);
679 * ibmvtpm_module_exit - Teardown ibm vtpm module
684 static void __exit ibmvtpm_module_exit(void)
686 vio_unregister_driver(&ibmvtpm_driver);
689 module_init(ibmvtpm_module_init);
690 module_exit(ibmvtpm_module_exit);
692 MODULE_AUTHOR("adlai@us.ibm.com");
693 MODULE_DESCRIPTION("IBM vTPM Driver");
694 MODULE_VERSION("1.0");
695 MODULE_LICENSE("GPL");