1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (C) 2012-2020 IBM Corporation
5 * Author: Ashley Lai <ashleydlai@gmail.com>
7 * Maintained by: <tpmdd-devel@lists.sourceforge.net>
9 * Device driver for TCG/TCPA TPM (trusted platform module).
10 * Specifications at www.trustedcomputinggroup.org
13 #include <linux/dma-mapping.h>
14 #include <linux/dmapool.h>
15 #include <linux/slab.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>
26 #include "tpm_ibmvtpm.h"
28 static const char tpm_ibmvtpm_driver_name[] = "tpm_ibmvtpm";
30 static const struct vio_device_id tpm_ibmvtpm_device_table[] = {
31 { "IBM,vtpm", "IBM,vtpm"},
32 { "IBM,vtpm", "IBM,vtpm20"},
35 MODULE_DEVICE_TABLE(vio, tpm_ibmvtpm_device_table);
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)
46 static int ibmvtpm_send_crq_word(struct vio_dev *vdev, u64 w1)
48 return plpar_hcall_norets(H_SEND_CRQ, vdev->unit_address, w1, 0);
52 * ibmvtpm_send_crq() - Send a CRQ request
54 * @vdev: vio device struct
60 * The ibmvtpm crq is defined as follows:
62 * Byte | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7
63 * -----------------------------------------------------------------------
64 * Word0 | Valid | Type | Length | Data
65 * -----------------------------------------------------------------------
67 * -----------------------------------------------------------------------
69 * Which matches the following structure (on bigendian host):
71 * struct ibmvtpm_crq {
77 * } __attribute__((packed, aligned(8)));
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.
84 * 0 (H_SUCCESS) - Success
87 static int ibmvtpm_send_crq(struct vio_dev *vdev,
88 u8 valid, u8 msg, u16 len, u32 data)
90 u64 w1 = ((u64)valid << 56) | ((u64)msg << 48) | ((u64)len << 32) |
92 return ibmvtpm_send_crq_word(vdev, w1);
96 * tpm_ibmvtpm_recv - Receive data after send
98 * @chip: tpm chip struct
99 * @buf: buffer to read
100 * @count: size of buffer
103 * Number of bytes read
105 static int tpm_ibmvtpm_recv(struct tpm_chip *chip, u8 *buf, size_t count)
107 struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev);
110 if (!ibmvtpm->rtce_buf) {
111 dev_err(ibmvtpm->dev, "ibmvtpm device is not ready\n");
115 len = ibmvtpm->res_len;
118 dev_err(ibmvtpm->dev,
119 "Invalid size in recv: count=%zd, crq_size=%d\n",
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);
133 * ibmvtpm_crq_send_init - Send a CRQ initialize message
134 * @ibmvtpm: vtpm device struct
138 * Non-zero on failure.
140 static int ibmvtpm_crq_send_init(struct ibmvtpm_dev *ibmvtpm)
144 rc = ibmvtpm_send_crq_word(ibmvtpm->vdev, INIT_CRQ_CMD);
146 dev_err(ibmvtpm->dev,
147 "%s failed rc=%d\n", __func__, rc);
153 * tpm_ibmvtpm_resume - Resume from suspend
155 * @dev: device struct
159 static int tpm_ibmvtpm_resume(struct device *dev)
161 struct tpm_chip *chip = dev_get_drvdata(dev);
162 struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev);
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));
173 dev_err(dev, "Error enabling ibmvtpm rc=%d\n", rc);
177 rc = vio_enable_interrupts(ibmvtpm->vdev);
179 dev_err(dev, "Error vio_enable_interrupts rc=%d\n", rc);
183 rc = ibmvtpm_crq_send_init(ibmvtpm);
185 dev_err(dev, "Error send_init rc=%d\n", rc);
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
200 static int tpm_ibmvtpm_send(struct tpm_chip *chip, u8 *buf, size_t count)
202 struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev);
206 if (!ibmvtpm->rtce_buf) {
207 dev_err(ibmvtpm->dev, "ibmvtpm device is not ready\n");
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);
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);
227 spin_lock(&ibmvtpm->rtce_lock);
228 ibmvtpm->res_len = 0;
229 memcpy((void *)ibmvtpm->rtce_buf, (void *)buf, count);
232 * set the processing flag before the Hcall, since we may get the
233 * result (interrupt) before even being able to check rc.
235 ibmvtpm->tpm_processing_cmd = 1;
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) {
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.
247 if (rc == H_CLOSED && retry) {
248 tpm_ibmvtpm_resume(ibmvtpm->dev);
252 dev_err(ibmvtpm->dev, "tpm_ibmvtpm_send failed rc=%d\n", rc);
253 ibmvtpm->tpm_processing_cmd = 0;
256 spin_unlock(&ibmvtpm->rtce_lock);
260 static void tpm_ibmvtpm_cancel(struct tpm_chip *chip)
265 static u8 tpm_ibmvtpm_status(struct tpm_chip *chip)
267 struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev);
269 return ibmvtpm->tpm_processing_cmd;
273 * ibmvtpm_crq_get_rtce_size - Send a CRQ request to get rtce size
275 * @ibmvtpm: vtpm device struct
279 * Non-zero on failure.
281 static int ibmvtpm_crq_get_rtce_size(struct ibmvtpm_dev *ibmvtpm)
285 rc = ibmvtpm_send_crq(ibmvtpm->vdev,
286 IBMVTPM_VALID_CMD, VTPM_GET_RTCE_BUFFER_SIZE, 0, 0);
288 dev_err(ibmvtpm->dev,
289 "ibmvtpm_crq_get_rtce_size failed rc=%d\n", rc);
295 * ibmvtpm_crq_get_version - Send a CRQ request to get vtpm version
296 * - Note that this is vtpm version and not tpm version
298 * @ibmvtpm: vtpm device struct
302 * Non-zero on failure.
304 static int ibmvtpm_crq_get_version(struct ibmvtpm_dev *ibmvtpm)
308 rc = ibmvtpm_send_crq(ibmvtpm->vdev,
309 IBMVTPM_VALID_CMD, VTPM_GET_VERSION, 0, 0);
311 dev_err(ibmvtpm->dev,
312 "ibmvtpm_crq_get_version failed rc=%d\n", rc);
318 * ibmvtpm_crq_send_init_complete - Send a CRQ initialize complete message
319 * @ibmvtpm: vtpm device struct
323 * Non-zero on failure.
325 static int ibmvtpm_crq_send_init_complete(struct ibmvtpm_dev *ibmvtpm)
329 rc = ibmvtpm_send_crq_word(ibmvtpm->vdev, INIT_CRQ_COMP_CMD);
331 dev_err(ibmvtpm->dev,
332 "ibmvtpm_crq_send_init_complete failed rc=%d\n", rc);
338 * tpm_ibmvtpm_remove - ibm vtpm remove entry point
339 * @vdev: vio device struct
343 static int tpm_ibmvtpm_remove(struct vio_dev *vdev)
345 struct tpm_chip *chip = dev_get_drvdata(&vdev->dev);
346 struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev);
349 tpm_chip_unregister(chip);
351 free_irq(vdev->irq, ibmvtpm);
356 rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address);
357 } while (rc == H_BUSY || H_IS_LONG_BUSY(rc));
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);
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);
370 /* For tpm_ibmvtpm_get_desired_dma */
371 dev_set_drvdata(&vdev->dev, NULL);
377 * tpm_ibmvtpm_get_desired_dma - Get DMA size needed by this driver
378 * @vdev: vio device struct
381 * Number of bytes the driver needs to DMA map.
383 static unsigned long tpm_ibmvtpm_get_desired_dma(struct vio_dev *vdev)
385 struct tpm_chip *chip = dev_get_drvdata(&vdev->dev);
386 struct ibmvtpm_dev *ibmvtpm;
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.
394 ibmvtpm = dev_get_drvdata(&chip->dev);
396 return CRQ_RES_BUF_SIZE + PAGE_SIZE;
398 return CRQ_RES_BUF_SIZE + ibmvtpm->rtce_size;
402 * tpm_ibmvtpm_suspend - Suspend
403 * @dev: device struct
407 static int tpm_ibmvtpm_suspend(struct device *dev)
409 struct tpm_chip *chip = dev_get_drvdata(dev);
410 struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev);
413 rc = ibmvtpm_send_crq(ibmvtpm->vdev,
414 IBMVTPM_VALID_CMD, VTPM_PREPARE_TO_SUSPEND, 0, 0);
416 dev_err(ibmvtpm->dev,
417 "tpm_ibmvtpm_suspend failed rc=%d\n", rc);
423 * ibmvtpm_reset_crq - Reset CRQ
425 * @ibmvtpm: ibm vtpm struct
429 * Non-zero on failure.
431 static int ibmvtpm_reset_crq(struct ibmvtpm_dev *ibmvtpm)
438 rc = plpar_hcall_norets(H_FREE_CRQ,
439 ibmvtpm->vdev->unit_address);
440 } while (rc == H_BUSY || H_IS_LONG_BUSY(rc));
442 memset(ibmvtpm->crq_queue.crq_addr, 0, CRQ_RES_BUF_SIZE);
443 ibmvtpm->crq_queue.index = 0;
445 return plpar_hcall_norets(H_REG_CRQ, ibmvtpm->vdev->unit_address,
446 ibmvtpm->crq_dma_handle, CRQ_RES_BUF_SIZE);
449 static bool tpm_ibmvtpm_req_canceled(struct tpm_chip *chip, u8 status)
451 return (status == 0);
454 static const struct tpm_class_ops tpm_ibmvtpm = {
455 .recv = tpm_ibmvtpm_recv,
456 .send = tpm_ibmvtpm_send,
457 .cancel = tpm_ibmvtpm_cancel,
458 .status = tpm_ibmvtpm_status,
459 .req_complete_mask = 1,
460 .req_complete_val = 0,
461 .req_canceled = tpm_ibmvtpm_req_canceled,
464 static const struct dev_pm_ops tpm_ibmvtpm_pm_ops = {
465 .suspend = tpm_ibmvtpm_suspend,
466 .resume = tpm_ibmvtpm_resume,
470 * ibmvtpm_crq_get_next - Get next responded crq
472 * @ibmvtpm: vtpm device struct
474 * Return: vtpm crq pointer or NULL.
476 static struct ibmvtpm_crq *ibmvtpm_crq_get_next(struct ibmvtpm_dev *ibmvtpm)
478 struct ibmvtpm_crq_queue *crq_q = &ibmvtpm->crq_queue;
479 struct ibmvtpm_crq *crq = &crq_q->crq_addr[crq_q->index];
481 if (crq->valid & VTPM_MSG_RES) {
482 if (++crq_q->index == crq_q->num_entry)
491 * ibmvtpm_crq_process - Process responded crq
493 * @crq: crq to be processed
494 * @ibmvtpm: vtpm device struct
497 static void ibmvtpm_crq_process(struct ibmvtpm_crq *crq,
498 struct ibmvtpm_dev *ibmvtpm)
502 switch (crq->valid) {
506 dev_info(ibmvtpm->dev, "CRQ initialized\n");
507 rc = ibmvtpm_crq_send_init_complete(ibmvtpm);
509 dev_err(ibmvtpm->dev, "Unable to send CRQ init complete rc=%d\n", rc);
511 case INIT_CRQ_COMP_RES:
512 dev_info(ibmvtpm->dev,
513 "CRQ initialization completed\n");
516 dev_err(ibmvtpm->dev, "Unknown crq message type: %d\n", crq->msg);
519 case IBMVTPM_VALID_CMD:
521 case VTPM_GET_RTCE_BUFFER_SIZE_RES:
522 if (be16_to_cpu(crq->len) <= 0) {
523 dev_err(ibmvtpm->dev, "Invalid rtce size\n");
526 ibmvtpm->rtce_size = be16_to_cpu(crq->len);
527 ibmvtpm->rtce_buf = kmalloc(ibmvtpm->rtce_size,
529 if (!ibmvtpm->rtce_buf) {
530 dev_err(ibmvtpm->dev, "Failed to allocate memory for rtce buffer\n");
534 ibmvtpm->rtce_dma_handle = dma_map_single(ibmvtpm->dev,
535 ibmvtpm->rtce_buf, ibmvtpm->rtce_size,
538 if (dma_mapping_error(ibmvtpm->dev,
539 ibmvtpm->rtce_dma_handle)) {
540 kfree(ibmvtpm->rtce_buf);
541 ibmvtpm->rtce_buf = NULL;
542 dev_err(ibmvtpm->dev, "Failed to dma map rtce buffer\n");
546 case VTPM_GET_VERSION_RES:
547 ibmvtpm->vtpm_version = be32_to_cpu(crq->data);
549 case VTPM_TPM_COMMAND_RES:
550 /* len of the data in rtce buffer */
551 ibmvtpm->res_len = be16_to_cpu(crq->len);
552 ibmvtpm->tpm_processing_cmd = 0;
553 wake_up_interruptible(&ibmvtpm->wq);
563 * ibmvtpm_interrupt - Interrupt handler
565 * @irq: irq number to handle
566 * @vtpm_instance: vtpm that received interrupt
571 static irqreturn_t ibmvtpm_interrupt(int irq, void *vtpm_instance)
573 struct ibmvtpm_dev *ibmvtpm = (struct ibmvtpm_dev *) vtpm_instance;
574 struct ibmvtpm_crq *crq;
576 /* while loop is needed for initial setup (get version and
577 * get rtce_size). There should be only one tpm request at any
580 while ((crq = ibmvtpm_crq_get_next(ibmvtpm)) != NULL) {
581 ibmvtpm_crq_process(crq, ibmvtpm);
582 wake_up_interruptible(&ibmvtpm->crq_queue.wq);
591 * tpm_ibmvtpm_probe - ibm vtpm initialize entry point
593 * @vio_dev: vio device struct
594 * @id: vio device id struct
598 * Non-zero on failure.
600 static int tpm_ibmvtpm_probe(struct vio_dev *vio_dev,
601 const struct vio_device_id *id)
603 struct ibmvtpm_dev *ibmvtpm;
604 struct device *dev = &vio_dev->dev;
605 struct ibmvtpm_crq_queue *crq_q;
606 struct tpm_chip *chip;
607 int rc = -ENOMEM, rc1;
609 chip = tpmm_chip_alloc(dev, &tpm_ibmvtpm);
611 return PTR_ERR(chip);
613 ibmvtpm = kzalloc(sizeof(struct ibmvtpm_dev), GFP_KERNEL);
615 dev_err(dev, "kzalloc for ibmvtpm failed\n");
620 ibmvtpm->vdev = vio_dev;
622 crq_q = &ibmvtpm->crq_queue;
623 crq_q->crq_addr = (struct ibmvtpm_crq *)get_zeroed_page(GFP_KERNEL);
624 if (!crq_q->crq_addr) {
625 dev_err(dev, "Unable to allocate memory for crq_addr\n");
629 crq_q->num_entry = CRQ_RES_BUF_SIZE / sizeof(*crq_q->crq_addr);
630 init_waitqueue_head(&crq_q->wq);
631 ibmvtpm->crq_dma_handle = dma_map_single(dev, crq_q->crq_addr,
635 if (dma_mapping_error(dev, ibmvtpm->crq_dma_handle)) {
636 dev_err(dev, "dma mapping failed\n");
640 rc = plpar_hcall_norets(H_REG_CRQ, vio_dev->unit_address,
641 ibmvtpm->crq_dma_handle, CRQ_RES_BUF_SIZE);
642 if (rc == H_RESOURCE)
643 rc = ibmvtpm_reset_crq(ibmvtpm);
646 dev_err(dev, "Unable to register CRQ rc=%d\n", rc);
647 goto reg_crq_cleanup;
650 rc = request_irq(vio_dev->irq, ibmvtpm_interrupt, 0,
651 tpm_ibmvtpm_driver_name, ibmvtpm);
653 dev_err(dev, "Error %d register irq 0x%x\n", rc, vio_dev->irq);
654 goto init_irq_cleanup;
657 rc = vio_enable_interrupts(vio_dev);
659 dev_err(dev, "Error %d enabling interrupts\n", rc);
660 goto init_irq_cleanup;
663 init_waitqueue_head(&ibmvtpm->wq);
667 dev_set_drvdata(&chip->dev, ibmvtpm);
669 spin_lock_init(&ibmvtpm->rtce_lock);
671 rc = ibmvtpm_crq_send_init(ibmvtpm);
673 goto init_irq_cleanup;
675 rc = ibmvtpm_crq_get_version(ibmvtpm);
677 goto init_irq_cleanup;
679 rc = ibmvtpm_crq_get_rtce_size(ibmvtpm);
681 goto init_irq_cleanup;
683 if (!wait_event_timeout(ibmvtpm->crq_queue.wq,
684 ibmvtpm->rtce_buf != NULL,
687 dev_err(dev, "CRQ response timed out\n");
688 goto init_irq_cleanup;
692 if (!strcmp(id->compat, "IBM,vtpm20"))
693 chip->flags |= TPM_CHIP_FLAG_TPM2;
695 rc = tpm_get_timeouts(chip);
697 goto init_irq_cleanup;
699 if (chip->flags & TPM_CHIP_FLAG_TPM2) {
700 rc = tpm2_get_cc_attrs_tbl(chip);
702 goto init_irq_cleanup;
705 return tpm_chip_register(chip);
708 rc1 = plpar_hcall_norets(H_FREE_CRQ, vio_dev->unit_address);
709 } while (rc1 == H_BUSY || H_IS_LONG_BUSY(rc1));
711 dma_unmap_single(dev, ibmvtpm->crq_dma_handle, CRQ_RES_BUF_SIZE,
716 free_page((unsigned long)crq_q->crq_addr);
723 static struct vio_driver ibmvtpm_driver = {
724 .id_table = tpm_ibmvtpm_device_table,
725 .probe = tpm_ibmvtpm_probe,
726 .remove = tpm_ibmvtpm_remove,
727 .get_desired_dma = tpm_ibmvtpm_get_desired_dma,
728 .name = tpm_ibmvtpm_driver_name,
729 .pm = &tpm_ibmvtpm_pm_ops,
733 * ibmvtpm_module_init - Initialize ibm vtpm module.
738 * Non-zero on failure.
740 static int __init ibmvtpm_module_init(void)
742 return vio_register_driver(&ibmvtpm_driver);
746 * ibmvtpm_module_exit - Tear down ibm vtpm module.
748 static void __exit ibmvtpm_module_exit(void)
750 vio_unregister_driver(&ibmvtpm_driver);
753 module_init(ibmvtpm_module_init);
754 module_exit(ibmvtpm_module_exit);
756 MODULE_AUTHOR("adlai@us.ibm.com");
757 MODULE_DESCRIPTION("IBM vTPM Driver");
758 MODULE_VERSION("1.0");
759 MODULE_LICENSE("GPL");