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 * tpm_ibmvtpm_recv - Receive data after send
58 * @chip: tpm chip struct
59 * @buf: buffer to read
60 * count: size of buffer
63 * Number of bytes read
65 static int tpm_ibmvtpm_recv(struct tpm_chip *chip, u8 *buf, size_t count)
67 struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev);
71 if (!ibmvtpm->rtce_buf) {
72 dev_err(ibmvtpm->dev, "ibmvtpm device is not ready\n");
76 sig = wait_event_interruptible(ibmvtpm->wq, !ibmvtpm->tpm_processing_cmd);
80 len = ibmvtpm->res_len;
84 "Invalid size in recv: count=%zd, crq_size=%d\n",
89 spin_lock(&ibmvtpm->rtce_lock);
90 memcpy((void *)buf, (void *)ibmvtpm->rtce_buf, len);
91 memset(ibmvtpm->rtce_buf, 0, len);
93 spin_unlock(&ibmvtpm->rtce_lock);
98 * tpm_ibmvtpm_send - Send tpm request
99 * @chip: tpm chip struct
100 * @buf: buffer contains data to send
101 * count: size of buffer
104 * Number of bytes sent
106 static int tpm_ibmvtpm_send(struct tpm_chip *chip, u8 *buf, size_t count)
108 struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev);
109 struct ibmvtpm_crq crq;
110 __be64 *word = (__be64 *)&crq;
113 if (!ibmvtpm->rtce_buf) {
114 dev_err(ibmvtpm->dev, "ibmvtpm device is not ready\n");
118 if (count > ibmvtpm->rtce_size) {
119 dev_err(ibmvtpm->dev,
120 "Invalid size in send: count=%zd, rtce_size=%d\n",
121 count, ibmvtpm->rtce_size);
125 if (ibmvtpm->tpm_processing_cmd) {
126 dev_info(ibmvtpm->dev,
127 "Need to wait for TPM to finish\n");
128 /* wait for previous command to finish */
129 sig = wait_event_interruptible(ibmvtpm->wq, !ibmvtpm->tpm_processing_cmd);
134 spin_lock(&ibmvtpm->rtce_lock);
135 ibmvtpm->res_len = 0;
136 memcpy((void *)ibmvtpm->rtce_buf, (void *)buf, count);
137 crq.valid = (u8)IBMVTPM_VALID_CMD;
138 crq.msg = (u8)VTPM_TPM_COMMAND;
139 crq.len = cpu_to_be16(count);
140 crq.data = cpu_to_be32(ibmvtpm->rtce_dma_handle);
143 * set the processing flag before the Hcall, since we may get the
144 * result (interrupt) before even being able to check rc.
146 ibmvtpm->tpm_processing_cmd = true;
148 rc = ibmvtpm_send_crq(ibmvtpm->vdev, be64_to_cpu(word[0]),
149 be64_to_cpu(word[1]));
150 if (rc != H_SUCCESS) {
151 dev_err(ibmvtpm->dev, "tpm_ibmvtpm_send failed rc=%d\n", rc);
153 ibmvtpm->tpm_processing_cmd = false;
157 spin_unlock(&ibmvtpm->rtce_lock);
161 static void tpm_ibmvtpm_cancel(struct tpm_chip *chip)
166 static u8 tpm_ibmvtpm_status(struct tpm_chip *chip)
172 * ibmvtpm_crq_get_rtce_size - Send a CRQ request to get rtce size
173 * @ibmvtpm: vtpm device struct
179 static int ibmvtpm_crq_get_rtce_size(struct ibmvtpm_dev *ibmvtpm)
181 struct ibmvtpm_crq crq;
182 u64 *buf = (u64 *) &crq;
185 crq.valid = (u8)IBMVTPM_VALID_CMD;
186 crq.msg = (u8)VTPM_GET_RTCE_BUFFER_SIZE;
188 rc = ibmvtpm_send_crq(ibmvtpm->vdev, cpu_to_be64(buf[0]),
189 cpu_to_be64(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, cpu_to_be64(buf[0]),
216 cpu_to_be64(buf[1]));
218 dev_err(ibmvtpm->dev,
219 "ibmvtpm_crq_get_version failed rc=%d\n", rc);
225 * ibmvtpm_crq_send_init_complete - Send a CRQ initialize complete message
226 * @ibmvtpm: vtpm device struct
232 static int ibmvtpm_crq_send_init_complete(struct ibmvtpm_dev *ibmvtpm)
236 rc = ibmvtpm_send_crq(ibmvtpm->vdev, INIT_CRQ_COMP_CMD, 0);
238 dev_err(ibmvtpm->dev,
239 "ibmvtpm_crq_send_init_complete failed rc=%d\n", rc);
245 * ibmvtpm_crq_send_init - Send a CRQ initialize message
246 * @ibmvtpm: vtpm device struct
252 static int ibmvtpm_crq_send_init(struct ibmvtpm_dev *ibmvtpm)
256 rc = ibmvtpm_send_crq(ibmvtpm->vdev, INIT_CRQ_CMD, 0);
258 dev_err(ibmvtpm->dev,
259 "ibmvtpm_crq_send_init failed rc=%d\n", rc);
265 * tpm_ibmvtpm_remove - ibm vtpm remove entry point
266 * @vdev: vio device struct
271 static int tpm_ibmvtpm_remove(struct vio_dev *vdev)
273 struct tpm_chip *chip = dev_get_drvdata(&vdev->dev);
274 struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev);
277 tpm_chip_unregister(chip);
279 free_irq(vdev->irq, ibmvtpm);
284 rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
285 } while (rc == H_BUSY || H_IS_LONG_BUSY(rc));
287 dma_unmap_single(ibmvtpm->dev, ibmvtpm->crq_dma_handle,
288 CRQ_RES_BUF_SIZE, DMA_BIDIRECTIONAL);
289 free_page((unsigned long)ibmvtpm->crq_queue.crq_addr);
291 if (ibmvtpm->rtce_buf) {
292 dma_unmap_single(ibmvtpm->dev, ibmvtpm->rtce_dma_handle,
293 ibmvtpm->rtce_size, DMA_BIDIRECTIONAL);
294 kfree(ibmvtpm->rtce_buf);
298 /* For tpm_ibmvtpm_get_desired_dma */
299 dev_set_drvdata(&vdev->dev, NULL);
305 * tpm_ibmvtpm_get_desired_dma - Get DMA size needed by this driver
306 * @vdev: vio device struct
309 * Number of bytes the driver needs to DMA map
311 static unsigned long tpm_ibmvtpm_get_desired_dma(struct vio_dev *vdev)
313 struct tpm_chip *chip = dev_get_drvdata(&vdev->dev);
314 struct ibmvtpm_dev *ibmvtpm;
317 * ibmvtpm initializes at probe time, so the data we are
318 * asking for may not be set yet. Estimate that 4K required
319 * for TCE-mapped buffer in addition to CRQ.
322 ibmvtpm = dev_get_drvdata(&chip->dev);
324 return CRQ_RES_BUF_SIZE + PAGE_SIZE;
326 return CRQ_RES_BUF_SIZE + ibmvtpm->rtce_size;
330 * tpm_ibmvtpm_suspend - Suspend
331 * @dev: device struct
336 static int tpm_ibmvtpm_suspend(struct device *dev)
338 struct tpm_chip *chip = dev_get_drvdata(dev);
339 struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev);
340 struct ibmvtpm_crq crq;
341 u64 *buf = (u64 *) &crq;
344 crq.valid = (u8)IBMVTPM_VALID_CMD;
345 crq.msg = (u8)VTPM_PREPARE_TO_SUSPEND;
347 rc = ibmvtpm_send_crq(ibmvtpm->vdev, cpu_to_be64(buf[0]),
348 cpu_to_be64(buf[1]));
350 dev_err(ibmvtpm->dev,
351 "tpm_ibmvtpm_suspend failed rc=%d\n", rc);
357 * ibmvtpm_reset_crq - Reset CRQ
358 * @ibmvtpm: ibm vtpm struct
364 static int ibmvtpm_reset_crq(struct ibmvtpm_dev *ibmvtpm)
371 rc = plpar_hcall_norets(H_FREE_CRQ,
372 ibmvtpm->vdev->unit_address);
373 } while (rc == H_BUSY || H_IS_LONG_BUSY(rc));
375 memset(ibmvtpm->crq_queue.crq_addr, 0, CRQ_RES_BUF_SIZE);
376 ibmvtpm->crq_queue.index = 0;
378 return plpar_hcall_norets(H_REG_CRQ, ibmvtpm->vdev->unit_address,
379 ibmvtpm->crq_dma_handle, CRQ_RES_BUF_SIZE);
383 * tpm_ibmvtpm_resume - Resume from suspend
384 * @dev: device struct
389 static int tpm_ibmvtpm_resume(struct device *dev)
391 struct tpm_chip *chip = dev_get_drvdata(dev);
392 struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev);
398 rc = plpar_hcall_norets(H_ENABLE_CRQ,
399 ibmvtpm->vdev->unit_address);
400 } while (rc == H_IN_PROGRESS || rc == H_BUSY || H_IS_LONG_BUSY(rc));
403 dev_err(dev, "Error enabling ibmvtpm rc=%d\n", rc);
407 rc = vio_enable_interrupts(ibmvtpm->vdev);
409 dev_err(dev, "Error vio_enable_interrupts rc=%d\n", rc);
413 rc = ibmvtpm_crq_send_init(ibmvtpm);
415 dev_err(dev, "Error send_init rc=%d\n", rc);
420 static bool tpm_ibmvtpm_req_canceled(struct tpm_chip *chip, u8 status)
422 return (status == 0);
425 static const struct tpm_class_ops tpm_ibmvtpm = {
426 .recv = tpm_ibmvtpm_recv,
427 .send = tpm_ibmvtpm_send,
428 .cancel = tpm_ibmvtpm_cancel,
429 .status = tpm_ibmvtpm_status,
430 .req_complete_mask = 0,
431 .req_complete_val = 0,
432 .req_canceled = tpm_ibmvtpm_req_canceled,
435 static const struct dev_pm_ops tpm_ibmvtpm_pm_ops = {
436 .suspend = tpm_ibmvtpm_suspend,
437 .resume = tpm_ibmvtpm_resume,
441 * ibmvtpm_crq_get_next - Get next responded crq
442 * @ibmvtpm vtpm device struct
447 static struct ibmvtpm_crq *ibmvtpm_crq_get_next(struct ibmvtpm_dev *ibmvtpm)
449 struct ibmvtpm_crq_queue *crq_q = &ibmvtpm->crq_queue;
450 struct ibmvtpm_crq *crq = &crq_q->crq_addr[crq_q->index];
452 if (crq->valid & VTPM_MSG_RES) {
453 if (++crq_q->index == crq_q->num_entry)
462 * ibmvtpm_crq_process - Process responded crq
463 * @crq crq to be processed
464 * @ibmvtpm vtpm device struct
469 static void ibmvtpm_crq_process(struct ibmvtpm_crq *crq,
470 struct ibmvtpm_dev *ibmvtpm)
474 switch (crq->valid) {
478 dev_info(ibmvtpm->dev, "CRQ initialized\n");
479 rc = ibmvtpm_crq_send_init_complete(ibmvtpm);
481 dev_err(ibmvtpm->dev, "Unable to send CRQ init complete rc=%d\n", rc);
483 case INIT_CRQ_COMP_RES:
484 dev_info(ibmvtpm->dev,
485 "CRQ initialization completed\n");
488 dev_err(ibmvtpm->dev, "Unknown crq message type: %d\n", crq->msg);
491 case IBMVTPM_VALID_CMD:
493 case VTPM_GET_RTCE_BUFFER_SIZE_RES:
494 if (be16_to_cpu(crq->len) <= 0) {
495 dev_err(ibmvtpm->dev, "Invalid rtce size\n");
498 ibmvtpm->rtce_size = be16_to_cpu(crq->len);
499 ibmvtpm->rtce_buf = kmalloc(ibmvtpm->rtce_size,
501 if (!ibmvtpm->rtce_buf) {
502 dev_err(ibmvtpm->dev, "Failed to allocate memory for rtce buffer\n");
506 ibmvtpm->rtce_dma_handle = dma_map_single(ibmvtpm->dev,
507 ibmvtpm->rtce_buf, ibmvtpm->rtce_size,
510 if (dma_mapping_error(ibmvtpm->dev,
511 ibmvtpm->rtce_dma_handle)) {
512 kfree(ibmvtpm->rtce_buf);
513 ibmvtpm->rtce_buf = NULL;
514 dev_err(ibmvtpm->dev, "Failed to dma map rtce buffer\n");
518 case VTPM_GET_VERSION_RES:
519 ibmvtpm->vtpm_version = be32_to_cpu(crq->data);
521 case VTPM_TPM_COMMAND_RES:
522 /* len of the data in rtce buffer */
523 ibmvtpm->res_len = be16_to_cpu(crq->len);
524 ibmvtpm->tpm_processing_cmd = false;
525 wake_up_interruptible(&ibmvtpm->wq);
535 * ibmvtpm_interrupt - Interrupt handler
536 * @irq: irq number to handle
537 * @vtpm_instance: vtpm that received interrupt
542 static irqreturn_t ibmvtpm_interrupt(int irq, void *vtpm_instance)
544 struct ibmvtpm_dev *ibmvtpm = (struct ibmvtpm_dev *) vtpm_instance;
545 struct ibmvtpm_crq *crq;
547 /* while loop is needed for initial setup (get version and
548 * get rtce_size). There should be only one tpm request at any
551 while ((crq = ibmvtpm_crq_get_next(ibmvtpm)) != NULL) {
552 ibmvtpm_crq_process(crq, ibmvtpm);
553 wake_up_interruptible(&ibmvtpm->crq_queue.wq);
562 * tpm_ibmvtpm_probe - ibm vtpm initialize entry point
563 * @vio_dev: vio device struct
564 * @id: vio device id struct
570 static int tpm_ibmvtpm_probe(struct vio_dev *vio_dev,
571 const struct vio_device_id *id)
573 struct ibmvtpm_dev *ibmvtpm;
574 struct device *dev = &vio_dev->dev;
575 struct ibmvtpm_crq_queue *crq_q;
576 struct tpm_chip *chip;
577 int rc = -ENOMEM, rc1;
579 chip = tpmm_chip_alloc(dev, &tpm_ibmvtpm);
581 return PTR_ERR(chip);
583 ibmvtpm = kzalloc(sizeof(struct ibmvtpm_dev), GFP_KERNEL);
585 dev_err(dev, "kzalloc for ibmvtpm failed\n");
590 ibmvtpm->vdev = vio_dev;
592 crq_q = &ibmvtpm->crq_queue;
593 crq_q->crq_addr = (struct ibmvtpm_crq *)get_zeroed_page(GFP_KERNEL);
594 if (!crq_q->crq_addr) {
595 dev_err(dev, "Unable to allocate memory for crq_addr\n");
599 crq_q->num_entry = CRQ_RES_BUF_SIZE / sizeof(*crq_q->crq_addr);
600 init_waitqueue_head(&crq_q->wq);
601 ibmvtpm->crq_dma_handle = dma_map_single(dev, crq_q->crq_addr,
605 if (dma_mapping_error(dev, ibmvtpm->crq_dma_handle)) {
606 dev_err(dev, "dma mapping failed\n");
610 rc = plpar_hcall_norets(H_REG_CRQ, vio_dev->unit_address,
611 ibmvtpm->crq_dma_handle, CRQ_RES_BUF_SIZE);
612 if (rc == H_RESOURCE)
613 rc = ibmvtpm_reset_crq(ibmvtpm);
616 dev_err(dev, "Unable to register CRQ rc=%d\n", rc);
617 goto reg_crq_cleanup;
620 rc = request_irq(vio_dev->irq, ibmvtpm_interrupt, 0,
621 tpm_ibmvtpm_driver_name, ibmvtpm);
623 dev_err(dev, "Error %d register irq 0x%x\n", rc, vio_dev->irq);
624 goto init_irq_cleanup;
627 rc = vio_enable_interrupts(vio_dev);
629 dev_err(dev, "Error %d enabling interrupts\n", rc);
630 goto init_irq_cleanup;
633 init_waitqueue_head(&ibmvtpm->wq);
637 dev_set_drvdata(&chip->dev, ibmvtpm);
639 spin_lock_init(&ibmvtpm->rtce_lock);
641 rc = ibmvtpm_crq_send_init(ibmvtpm);
643 goto init_irq_cleanup;
645 rc = ibmvtpm_crq_get_version(ibmvtpm);
647 goto init_irq_cleanup;
649 rc = ibmvtpm_crq_get_rtce_size(ibmvtpm);
651 goto init_irq_cleanup;
653 if (!wait_event_timeout(ibmvtpm->crq_queue.wq,
654 ibmvtpm->rtce_buf != NULL,
657 dev_err(dev, "CRQ response timed out\n");
658 goto init_irq_cleanup;
661 return tpm_chip_register(chip);
664 rc1 = plpar_hcall_norets(H_FREE_CRQ, vio_dev->unit_address);
665 } while (rc1 == H_BUSY || H_IS_LONG_BUSY(rc1));
667 dma_unmap_single(dev, ibmvtpm->crq_dma_handle, CRQ_RES_BUF_SIZE,
672 free_page((unsigned long)crq_q->crq_addr);
679 static struct vio_driver ibmvtpm_driver = {
680 .id_table = tpm_ibmvtpm_device_table,
681 .probe = tpm_ibmvtpm_probe,
682 .remove = tpm_ibmvtpm_remove,
683 .get_desired_dma = tpm_ibmvtpm_get_desired_dma,
684 .name = tpm_ibmvtpm_driver_name,
685 .pm = &tpm_ibmvtpm_pm_ops,
689 * ibmvtpm_module_init - Initialize ibm vtpm module
695 static int __init ibmvtpm_module_init(void)
697 return vio_register_driver(&ibmvtpm_driver);
701 * ibmvtpm_module_exit - Teardown ibm vtpm module
706 static void __exit ibmvtpm_module_exit(void)
708 vio_unregister_driver(&ibmvtpm_driver);
711 module_init(ibmvtpm_module_init);
712 module_exit(ibmvtpm_module_exit);
714 MODULE_AUTHOR("adlai@us.ibm.com");
715 MODULE_DESCRIPTION("IBM vTPM Driver");
716 MODULE_VERSION("1.0");
717 MODULE_LICENSE("GPL");