/* * Copyright (C) 2012 IBM Corporation * * Author: Ashley Lai * * Maintained by: * * Device driver for TCG/TCPA TPM (trusted platform module). * Specifications at www.trustedcomputinggroup.org * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation, version 2 of the * License. * */ #include #include #include #include #include #include #include #include #include #include #include #include "tpm.h" #include "tpm_ibmvtpm.h" static const char tpm_ibmvtpm_driver_name[] = "tpm_ibmvtpm"; static struct vio_device_id tpm_ibmvtpm_device_table[] = { { "IBM,vtpm", "IBM,vtpm"}, { "", "" } }; MODULE_DEVICE_TABLE(vio, tpm_ibmvtpm_device_table); /** * ibmvtpm_send_crq - Send a CRQ request * @vdev: vio device struct * @w1: first word * @w2: second word * * Return value: * 0 -Sucess * Non-zero - Failure */ static int ibmvtpm_send_crq(struct vio_dev *vdev, u64 w1, u64 w2) { return plpar_hcall_norets(H_SEND_CRQ, vdev->unit_address, w1, w2); } /** * tpm_ibmvtpm_recv - Receive data after send * @chip: tpm chip struct * @buf: buffer to read * count: size of buffer * * Return value: * Number of bytes read */ static int tpm_ibmvtpm_recv(struct tpm_chip *chip, u8 *buf, size_t count) { struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev); u16 len; int sig; if (!ibmvtpm->rtce_buf) { dev_err(ibmvtpm->dev, "ibmvtpm device is not ready\n"); return 0; } sig = wait_event_interruptible(ibmvtpm->wq, !ibmvtpm->tpm_processing_cmd); if (sig) return -EINTR; len = ibmvtpm->res_len; if (count < len) { dev_err(ibmvtpm->dev, "Invalid size in recv: count=%zd, crq_size=%d\n", count, len); return -EIO; } spin_lock(&ibmvtpm->rtce_lock); memcpy((void *)buf, (void *)ibmvtpm->rtce_buf, len); memset(ibmvtpm->rtce_buf, 0, len); ibmvtpm->res_len = 0; spin_unlock(&ibmvtpm->rtce_lock); return len; } /** * tpm_ibmvtpm_send - Send tpm request * @chip: tpm chip struct * @buf: buffer contains data to send * count: size of buffer * * Return value: * Number of bytes sent */ static int tpm_ibmvtpm_send(struct tpm_chip *chip, u8 *buf, size_t count) { struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev); struct ibmvtpm_crq crq; __be64 *word = (__be64 *)&crq; int rc, sig; if (!ibmvtpm->rtce_buf) { dev_err(ibmvtpm->dev, "ibmvtpm device is not ready\n"); return 0; } if (count > ibmvtpm->rtce_size) { dev_err(ibmvtpm->dev, "Invalid size in send: count=%zd, rtce_size=%d\n", count, ibmvtpm->rtce_size); return -EIO; } if (ibmvtpm->tpm_processing_cmd) { dev_info(ibmvtpm->dev, "Need to wait for TPM to finish\n"); /* wait for previous command to finish */ sig = wait_event_interruptible(ibmvtpm->wq, !ibmvtpm->tpm_processing_cmd); if (sig) return -EINTR; } spin_lock(&ibmvtpm->rtce_lock); ibmvtpm->res_len = 0; memcpy((void *)ibmvtpm->rtce_buf, (void *)buf, count); crq.valid = (u8)IBMVTPM_VALID_CMD; crq.msg = (u8)VTPM_TPM_COMMAND; crq.len = cpu_to_be16(count); crq.data = cpu_to_be32(ibmvtpm->rtce_dma_handle); /* * set the processing flag before the Hcall, since we may get the * result (interrupt) before even being able to check rc. */ ibmvtpm->tpm_processing_cmd = true; rc = ibmvtpm_send_crq(ibmvtpm->vdev, be64_to_cpu(word[0]), be64_to_cpu(word[1])); if (rc != H_SUCCESS) { dev_err(ibmvtpm->dev, "tpm_ibmvtpm_send failed rc=%d\n", rc); rc = 0; ibmvtpm->tpm_processing_cmd = false; } else rc = count; spin_unlock(&ibmvtpm->rtce_lock); return rc; } static void tpm_ibmvtpm_cancel(struct tpm_chip *chip) { return; } static u8 tpm_ibmvtpm_status(struct tpm_chip *chip) { return 0; } /** * ibmvtpm_crq_get_rtce_size - Send a CRQ request to get rtce size * @ibmvtpm: vtpm device struct * * Return value: * 0 - Success * Non-zero - Failure */ static int ibmvtpm_crq_get_rtce_size(struct ibmvtpm_dev *ibmvtpm) { struct ibmvtpm_crq crq; u64 *buf = (u64 *) &crq; int rc; crq.valid = (u8)IBMVTPM_VALID_CMD; crq.msg = (u8)VTPM_GET_RTCE_BUFFER_SIZE; rc = ibmvtpm_send_crq(ibmvtpm->vdev, cpu_to_be64(buf[0]), cpu_to_be64(buf[1])); if (rc != H_SUCCESS) dev_err(ibmvtpm->dev, "ibmvtpm_crq_get_rtce_size failed rc=%d\n", rc); return rc; } /** * ibmvtpm_crq_get_version - Send a CRQ request to get vtpm version * - Note that this is vtpm version and not tpm version * @ibmvtpm: vtpm device struct * * Return value: * 0 - Success * Non-zero - Failure */ static int ibmvtpm_crq_get_version(struct ibmvtpm_dev *ibmvtpm) { struct ibmvtpm_crq crq; u64 *buf = (u64 *) &crq; int rc; crq.valid = (u8)IBMVTPM_VALID_CMD; crq.msg = (u8)VTPM_GET_VERSION; rc = ibmvtpm_send_crq(ibmvtpm->vdev, cpu_to_be64(buf[0]), cpu_to_be64(buf[1])); if (rc != H_SUCCESS) dev_err(ibmvtpm->dev, "ibmvtpm_crq_get_version failed rc=%d\n", rc); return rc; } /** * ibmvtpm_crq_send_init_complete - Send a CRQ initialize complete message * @ibmvtpm: vtpm device struct * * Return value: * 0 - Success * Non-zero - Failure */ static int ibmvtpm_crq_send_init_complete(struct ibmvtpm_dev *ibmvtpm) { int rc; rc = ibmvtpm_send_crq(ibmvtpm->vdev, INIT_CRQ_COMP_CMD, 0); if (rc != H_SUCCESS) dev_err(ibmvtpm->dev, "ibmvtpm_crq_send_init_complete failed rc=%d\n", rc); return rc; } /** * ibmvtpm_crq_send_init - Send a CRQ initialize message * @ibmvtpm: vtpm device struct * * Return value: * 0 - Success * Non-zero - Failure */ static int ibmvtpm_crq_send_init(struct ibmvtpm_dev *ibmvtpm) { int rc; rc = ibmvtpm_send_crq(ibmvtpm->vdev, INIT_CRQ_CMD, 0); if (rc != H_SUCCESS) dev_err(ibmvtpm->dev, "ibmvtpm_crq_send_init failed rc=%d\n", rc); return rc; } /** * tpm_ibmvtpm_remove - ibm vtpm remove entry point * @vdev: vio device struct * * Return value: * 0 */ static int tpm_ibmvtpm_remove(struct vio_dev *vdev) { struct tpm_chip *chip = dev_get_drvdata(&vdev->dev); struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev); int rc = 0; tpm_chip_unregister(chip); free_irq(vdev->irq, ibmvtpm); do { if (rc) msleep(100); rc = plpar_hcall_norets(H_FREE_CRQ, vdev->unit_address); } while (rc == H_BUSY || H_IS_LONG_BUSY(rc)); dma_unmap_single(ibmvtpm->dev, ibmvtpm->crq_dma_handle, CRQ_RES_BUF_SIZE, DMA_BIDIRECTIONAL); free_page((unsigned long)ibmvtpm->crq_queue.crq_addr); if (ibmvtpm->rtce_buf) { dma_unmap_single(ibmvtpm->dev, ibmvtpm->rtce_dma_handle, ibmvtpm->rtce_size, DMA_BIDIRECTIONAL); kfree(ibmvtpm->rtce_buf); } kfree(ibmvtpm); /* For tpm_ibmvtpm_get_desired_dma */ dev_set_drvdata(&vdev->dev, NULL); return 0; } /** * tpm_ibmvtpm_get_desired_dma - Get DMA size needed by this driver * @vdev: vio device struct * * Return value: * Number of bytes the driver needs to DMA map */ static unsigned long tpm_ibmvtpm_get_desired_dma(struct vio_dev *vdev) { struct tpm_chip *chip = dev_get_drvdata(&vdev->dev); struct ibmvtpm_dev *ibmvtpm; /* * ibmvtpm initializes at probe time, so the data we are * asking for may not be set yet. Estimate that 4K required * for TCE-mapped buffer in addition to CRQ. */ if (chip) ibmvtpm = dev_get_drvdata(&chip->dev); else return CRQ_RES_BUF_SIZE + PAGE_SIZE; return CRQ_RES_BUF_SIZE + ibmvtpm->rtce_size; } /** * tpm_ibmvtpm_suspend - Suspend * @dev: device struct * * Return value: * 0 */ static int tpm_ibmvtpm_suspend(struct device *dev) { struct tpm_chip *chip = dev_get_drvdata(dev); struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev); struct ibmvtpm_crq crq; u64 *buf = (u64 *) &crq; int rc = 0; crq.valid = (u8)IBMVTPM_VALID_CMD; crq.msg = (u8)VTPM_PREPARE_TO_SUSPEND; rc = ibmvtpm_send_crq(ibmvtpm->vdev, cpu_to_be64(buf[0]), cpu_to_be64(buf[1])); if (rc != H_SUCCESS) dev_err(ibmvtpm->dev, "tpm_ibmvtpm_suspend failed rc=%d\n", rc); return rc; } /** * ibmvtpm_reset_crq - Reset CRQ * @ibmvtpm: ibm vtpm struct * * Return value: * 0 - Success * Non-zero - Failure */ static int ibmvtpm_reset_crq(struct ibmvtpm_dev *ibmvtpm) { int rc = 0; do { if (rc) msleep(100); rc = plpar_hcall_norets(H_FREE_CRQ, ibmvtpm->vdev->unit_address); } while (rc == H_BUSY || H_IS_LONG_BUSY(rc)); memset(ibmvtpm->crq_queue.crq_addr, 0, CRQ_RES_BUF_SIZE); ibmvtpm->crq_queue.index = 0; return plpar_hcall_norets(H_REG_CRQ, ibmvtpm->vdev->unit_address, ibmvtpm->crq_dma_handle, CRQ_RES_BUF_SIZE); } /** * tpm_ibmvtpm_resume - Resume from suspend * @dev: device struct * * Return value: * 0 */ static int tpm_ibmvtpm_resume(struct device *dev) { struct tpm_chip *chip = dev_get_drvdata(dev); struct ibmvtpm_dev *ibmvtpm = dev_get_drvdata(&chip->dev); int rc = 0; do { if (rc) msleep(100); rc = plpar_hcall_norets(H_ENABLE_CRQ, ibmvtpm->vdev->unit_address); } while (rc == H_IN_PROGRESS || rc == H_BUSY || H_IS_LONG_BUSY(rc)); if (rc) { dev_err(dev, "Error enabling ibmvtpm rc=%d\n", rc); return rc; } rc = vio_enable_interrupts(ibmvtpm->vdev); if (rc) { dev_err(dev, "Error vio_enable_interrupts rc=%d\n", rc); return rc; } rc = ibmvtpm_crq_send_init(ibmvtpm); if (rc) dev_err(dev, "Error send_init rc=%d\n", rc); return rc; } static bool tpm_ibmvtpm_req_canceled(struct tpm_chip *chip, u8 status) { return (status == 0); } static const struct tpm_class_ops tpm_ibmvtpm = { .recv = tpm_ibmvtpm_recv, .send = tpm_ibmvtpm_send, .cancel = tpm_ibmvtpm_cancel, .status = tpm_ibmvtpm_status, .req_complete_mask = 0, .req_complete_val = 0, .req_canceled = tpm_ibmvtpm_req_canceled, }; static const struct dev_pm_ops tpm_ibmvtpm_pm_ops = { .suspend = tpm_ibmvtpm_suspend, .resume = tpm_ibmvtpm_resume, }; /** * ibmvtpm_crq_get_next - Get next responded crq * @ibmvtpm vtpm device struct * * Return value: * vtpm crq pointer */ static struct ibmvtpm_crq *ibmvtpm_crq_get_next(struct ibmvtpm_dev *ibmvtpm) { struct ibmvtpm_crq_queue *crq_q = &ibmvtpm->crq_queue; struct ibmvtpm_crq *crq = &crq_q->crq_addr[crq_q->index]; if (crq->valid & VTPM_MSG_RES) { if (++crq_q->index == crq_q->num_entry) crq_q->index = 0; smp_rmb(); } else crq = NULL; return crq; } /** * ibmvtpm_crq_process - Process responded crq * @crq crq to be processed * @ibmvtpm vtpm device struct * * Return value: * Nothing */ static void ibmvtpm_crq_process(struct ibmvtpm_crq *crq, struct ibmvtpm_dev *ibmvtpm) { int rc = 0; switch (crq->valid) { case VALID_INIT_CRQ: switch (crq->msg) { case INIT_CRQ_RES: dev_info(ibmvtpm->dev, "CRQ initialized\n"); rc = ibmvtpm_crq_send_init_complete(ibmvtpm); if (rc) dev_err(ibmvtpm->dev, "Unable to send CRQ init complete rc=%d\n", rc); return; case INIT_CRQ_COMP_RES: dev_info(ibmvtpm->dev, "CRQ initialization completed\n"); return; default: dev_err(ibmvtpm->dev, "Unknown crq message type: %d\n", crq->msg); return; } case IBMVTPM_VALID_CMD: switch (crq->msg) { case VTPM_GET_RTCE_BUFFER_SIZE_RES: if (be16_to_cpu(crq->len) <= 0) { dev_err(ibmvtpm->dev, "Invalid rtce size\n"); return; } ibmvtpm->rtce_size = be16_to_cpu(crq->len); ibmvtpm->rtce_buf = kmalloc(ibmvtpm->rtce_size, GFP_ATOMIC); if (!ibmvtpm->rtce_buf) { dev_err(ibmvtpm->dev, "Failed to allocate memory for rtce buffer\n"); return; } ibmvtpm->rtce_dma_handle = dma_map_single(ibmvtpm->dev, ibmvtpm->rtce_buf, ibmvtpm->rtce_size, DMA_BIDIRECTIONAL); if (dma_mapping_error(ibmvtpm->dev, ibmvtpm->rtce_dma_handle)) { kfree(ibmvtpm->rtce_buf); ibmvtpm->rtce_buf = NULL; dev_err(ibmvtpm->dev, "Failed to dma map rtce buffer\n"); } return; case VTPM_GET_VERSION_RES: ibmvtpm->vtpm_version = be32_to_cpu(crq->data); return; case VTPM_TPM_COMMAND_RES: /* len of the data in rtce buffer */ ibmvtpm->res_len = be16_to_cpu(crq->len); ibmvtpm->tpm_processing_cmd = false; wake_up_interruptible(&ibmvtpm->wq); return; default: return; } } return; } /** * ibmvtpm_interrupt - Interrupt handler * @irq: irq number to handle * @vtpm_instance: vtpm that received interrupt * * Returns: * IRQ_HANDLED **/ static irqreturn_t ibmvtpm_interrupt(int irq, void *vtpm_instance) { struct ibmvtpm_dev *ibmvtpm = (struct ibmvtpm_dev *) vtpm_instance; struct ibmvtpm_crq *crq; /* while loop is needed for initial setup (get version and * get rtce_size). There should be only one tpm request at any * given time. */ while ((crq = ibmvtpm_crq_get_next(ibmvtpm)) != NULL) { ibmvtpm_crq_process(crq, ibmvtpm); wake_up_interruptible(&ibmvtpm->crq_queue.wq); crq->valid = 0; smp_wmb(); } return IRQ_HANDLED; } /** * tpm_ibmvtpm_probe - ibm vtpm initialize entry point * @vio_dev: vio device struct * @id: vio device id struct * * Return value: * 0 - Success * Non-zero - Failure */ static int tpm_ibmvtpm_probe(struct vio_dev *vio_dev, const struct vio_device_id *id) { struct ibmvtpm_dev *ibmvtpm; struct device *dev = &vio_dev->dev; struct ibmvtpm_crq_queue *crq_q; struct tpm_chip *chip; int rc = -ENOMEM, rc1; chip = tpmm_chip_alloc(dev, &tpm_ibmvtpm); if (IS_ERR(chip)) return PTR_ERR(chip); ibmvtpm = kzalloc(sizeof(struct ibmvtpm_dev), GFP_KERNEL); if (!ibmvtpm) { dev_err(dev, "kzalloc for ibmvtpm failed\n"); goto cleanup; } ibmvtpm->dev = dev; ibmvtpm->vdev = vio_dev; crq_q = &ibmvtpm->crq_queue; crq_q->crq_addr = (struct ibmvtpm_crq *)get_zeroed_page(GFP_KERNEL); if (!crq_q->crq_addr) { dev_err(dev, "Unable to allocate memory for crq_addr\n"); goto cleanup; } crq_q->num_entry = CRQ_RES_BUF_SIZE / sizeof(*crq_q->crq_addr); init_waitqueue_head(&crq_q->wq); ibmvtpm->crq_dma_handle = dma_map_single(dev, crq_q->crq_addr, CRQ_RES_BUF_SIZE, DMA_BIDIRECTIONAL); if (dma_mapping_error(dev, ibmvtpm->crq_dma_handle)) { dev_err(dev, "dma mapping failed\n"); goto cleanup; } rc = plpar_hcall_norets(H_REG_CRQ, vio_dev->unit_address, ibmvtpm->crq_dma_handle, CRQ_RES_BUF_SIZE); if (rc == H_RESOURCE) rc = ibmvtpm_reset_crq(ibmvtpm); if (rc) { dev_err(dev, "Unable to register CRQ rc=%d\n", rc); goto reg_crq_cleanup; } rc = request_irq(vio_dev->irq, ibmvtpm_interrupt, 0, tpm_ibmvtpm_driver_name, ibmvtpm); if (rc) { dev_err(dev, "Error %d register irq 0x%x\n", rc, vio_dev->irq); goto init_irq_cleanup; } rc = vio_enable_interrupts(vio_dev); if (rc) { dev_err(dev, "Error %d enabling interrupts\n", rc); goto init_irq_cleanup; } init_waitqueue_head(&ibmvtpm->wq); crq_q->index = 0; dev_set_drvdata(&chip->dev, ibmvtpm); spin_lock_init(&ibmvtpm->rtce_lock); rc = ibmvtpm_crq_send_init(ibmvtpm); if (rc) goto init_irq_cleanup; rc = ibmvtpm_crq_get_version(ibmvtpm); if (rc) goto init_irq_cleanup; rc = ibmvtpm_crq_get_rtce_size(ibmvtpm); if (rc) goto init_irq_cleanup; if (!wait_event_timeout(ibmvtpm->crq_queue.wq, ibmvtpm->rtce_buf != NULL, HZ)) { dev_err(dev, "CRQ response timed out\n"); goto init_irq_cleanup; } return tpm_chip_register(chip); init_irq_cleanup: do { rc1 = plpar_hcall_norets(H_FREE_CRQ, vio_dev->unit_address); } while (rc1 == H_BUSY || H_IS_LONG_BUSY(rc1)); reg_crq_cleanup: dma_unmap_single(dev, ibmvtpm->crq_dma_handle, CRQ_RES_BUF_SIZE, DMA_BIDIRECTIONAL); cleanup: if (ibmvtpm) { if (crq_q->crq_addr) free_page((unsigned long)crq_q->crq_addr); kfree(ibmvtpm); } return rc; } static struct vio_driver ibmvtpm_driver = { .id_table = tpm_ibmvtpm_device_table, .probe = tpm_ibmvtpm_probe, .remove = tpm_ibmvtpm_remove, .get_desired_dma = tpm_ibmvtpm_get_desired_dma, .name = tpm_ibmvtpm_driver_name, .pm = &tpm_ibmvtpm_pm_ops, }; /** * ibmvtpm_module_init - Initialize ibm vtpm module * * Return value: * 0 -Success * Non-zero - Failure */ static int __init ibmvtpm_module_init(void) { return vio_register_driver(&ibmvtpm_driver); } /** * ibmvtpm_module_exit - Teardown ibm vtpm module * * Return value: * Nothing */ static void __exit ibmvtpm_module_exit(void) { vio_unregister_driver(&ibmvtpm_driver); } module_init(ibmvtpm_module_init); module_exit(ibmvtpm_module_exit); MODULE_AUTHOR("adlai@us.ibm.com"); MODULE_DESCRIPTION("IBM vTPM Driver"); MODULE_VERSION("1.0"); MODULE_LICENSE("GPL");