X-Git-Url: https://gerrit.opnfv.org/gerrit/gitweb?a=blobdiff_plain;f=kernel%2Fdrivers%2Fchar%2Ftpm%2Ftpm_crb.c;fp=kernel%2Fdrivers%2Fchar%2Ftpm%2Ftpm_crb.c;h=b26ceee3585e1fbd91bff48cc6f75984a739f488;hb=9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00;hp=0000000000000000000000000000000000000000;hpb=98260f3884f4a202f9ca5eabed40b1354c489b29;p=kvmfornfv.git diff --git a/kernel/drivers/char/tpm/tpm_crb.c b/kernel/drivers/char/tpm/tpm_crb.c new file mode 100644 index 000000000..b26ceee35 --- /dev/null +++ b/kernel/drivers/char/tpm/tpm_crb.c @@ -0,0 +1,344 @@ +/* + * Copyright (C) 2014 Intel Corporation + * + * Authors: + * Jarkko Sakkinen + * + * Maintained by: + * + * This device driver implements the TPM interface as defined in + * the TCG CRB 2.0 TPM specification. + * + * 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 "tpm.h" + +#define ACPI_SIG_TPM2 "TPM2" + +static const u8 CRB_ACPI_START_UUID[] = { + /* 0000 */ 0xAB, 0x6C, 0xBF, 0x6B, 0x63, 0x54, 0x14, 0x47, + /* 0008 */ 0xB7, 0xCD, 0xF0, 0x20, 0x3C, 0x03, 0x68, 0xD4 +}; + +enum crb_defaults { + CRB_ACPI_START_REVISION_ID = 1, + CRB_ACPI_START_INDEX = 1, +}; + +enum crb_start_method { + CRB_SM_ACPI_START = 2, + CRB_SM_CRB = 7, + CRB_SM_CRB_WITH_ACPI_START = 8, +}; + +struct acpi_tpm2 { + struct acpi_table_header hdr; + u16 platform_class; + u16 reserved; + u64 control_area_pa; + u32 start_method; +} __packed; + +enum crb_ca_request { + CRB_CA_REQ_GO_IDLE = BIT(0), + CRB_CA_REQ_CMD_READY = BIT(1), +}; + +enum crb_ca_status { + CRB_CA_STS_ERROR = BIT(0), + CRB_CA_STS_TPM_IDLE = BIT(1), +}; + +enum crb_start { + CRB_START_INVOKE = BIT(0), +}; + +enum crb_cancel { + CRB_CANCEL_INVOKE = BIT(0), +}; + +struct crb_control_area { + u32 req; + u32 sts; + u32 cancel; + u32 start; + u32 int_enable; + u32 int_sts; + u32 cmd_size; + u64 cmd_pa; + u32 rsp_size; + u64 rsp_pa; +} __packed; + +enum crb_status { + CRB_STS_COMPLETE = BIT(0), +}; + +enum crb_flags { + CRB_FL_ACPI_START = BIT(0), + CRB_FL_CRB_START = BIT(1), +}; + +struct crb_priv { + unsigned int flags; + struct crb_control_area __iomem *cca; + u8 __iomem *cmd; + u8 __iomem *rsp; +}; + +static SIMPLE_DEV_PM_OPS(crb_pm, tpm_pm_suspend, tpm_pm_resume); + +static u8 crb_status(struct tpm_chip *chip) +{ + struct crb_priv *priv = chip->vendor.priv; + u8 sts = 0; + + if ((le32_to_cpu(ioread32(&priv->cca->start)) & CRB_START_INVOKE) != + CRB_START_INVOKE) + sts |= CRB_STS_COMPLETE; + + return sts; +} + +static int crb_recv(struct tpm_chip *chip, u8 *buf, size_t count) +{ + struct crb_priv *priv = chip->vendor.priv; + unsigned int expected; + + /* sanity check */ + if (count < 6) + return -EIO; + + if (le32_to_cpu(ioread32(&priv->cca->sts)) & CRB_CA_STS_ERROR) + return -EIO; + + memcpy_fromio(buf, priv->rsp, 6); + expected = be32_to_cpup((__be32 *) &buf[2]); + + if (expected > count) + return -EIO; + + memcpy_fromio(&buf[6], &priv->rsp[6], expected - 6); + + return expected; +} + +static int crb_do_acpi_start(struct tpm_chip *chip) +{ + union acpi_object *obj; + int rc; + + obj = acpi_evaluate_dsm(chip->acpi_dev_handle, + CRB_ACPI_START_UUID, + CRB_ACPI_START_REVISION_ID, + CRB_ACPI_START_INDEX, + NULL); + if (!obj) + return -ENXIO; + rc = obj->integer.value == 0 ? 0 : -ENXIO; + ACPI_FREE(obj); + return rc; +} + +static int crb_send(struct tpm_chip *chip, u8 *buf, size_t len) +{ + struct crb_priv *priv = chip->vendor.priv; + int rc = 0; + + if (len > le32_to_cpu(ioread32(&priv->cca->cmd_size))) { + dev_err(&chip->dev, + "invalid command count value %x %zx\n", + (unsigned int) len, + (size_t) le32_to_cpu(ioread32(&priv->cca->cmd_size))); + return -E2BIG; + } + + memcpy_toio(priv->cmd, buf, len); + + /* Make sure that cmd is populated before issuing start. */ + wmb(); + + if (priv->flags & CRB_FL_CRB_START) + iowrite32(cpu_to_le32(CRB_START_INVOKE), &priv->cca->start); + + if (priv->flags & CRB_FL_ACPI_START) + rc = crb_do_acpi_start(chip); + + return rc; +} + +static void crb_cancel(struct tpm_chip *chip) +{ + struct crb_priv *priv = chip->vendor.priv; + + iowrite32(cpu_to_le32(CRB_CANCEL_INVOKE), &priv->cca->cancel); + + /* Make sure that cmd is populated before issuing cancel. */ + wmb(); + + if ((priv->flags & CRB_FL_ACPI_START) && crb_do_acpi_start(chip)) + dev_err(&chip->dev, "ACPI Start failed\n"); + + iowrite32(0, &priv->cca->cancel); +} + +static bool crb_req_canceled(struct tpm_chip *chip, u8 status) +{ + struct crb_priv *priv = chip->vendor.priv; + u32 cancel = le32_to_cpu(ioread32(&priv->cca->cancel)); + + return (cancel & CRB_CANCEL_INVOKE) == CRB_CANCEL_INVOKE; +} + +static const struct tpm_class_ops tpm_crb = { + .status = crb_status, + .recv = crb_recv, + .send = crb_send, + .cancel = crb_cancel, + .req_canceled = crb_req_canceled, + .req_complete_mask = CRB_STS_COMPLETE, + .req_complete_val = CRB_STS_COMPLETE, +}; + +static int crb_acpi_add(struct acpi_device *device) +{ + struct tpm_chip *chip; + struct acpi_tpm2 *buf; + struct crb_priv *priv; + struct device *dev = &device->dev; + acpi_status status; + u32 sm; + u64 pa; + int rc; + + chip = tpmm_chip_alloc(dev, &tpm_crb); + if (IS_ERR(chip)) + return PTR_ERR(chip); + + chip->flags = TPM_CHIP_FLAG_TPM2; + + status = acpi_get_table(ACPI_SIG_TPM2, 1, + (struct acpi_table_header **) &buf); + if (ACPI_FAILURE(status)) { + dev_err(dev, "failed to get TPM2 ACPI table\n"); + return -ENODEV; + } + + if (buf->hdr.length < sizeof(struct acpi_tpm2)) { + dev_err(dev, "TPM2 ACPI table has wrong size"); + return -EINVAL; + } + + priv = (struct crb_priv *) devm_kzalloc(dev, sizeof(struct crb_priv), + GFP_KERNEL); + if (!priv) { + dev_err(dev, "failed to devm_kzalloc for private data\n"); + return -ENOMEM; + } + + sm = le32_to_cpu(buf->start_method); + + /* The reason for the extra quirk is that the PTT in 4th Gen Core CPUs + * report only ACPI start but in practice seems to require both + * ACPI start and CRB start. + */ + if (sm == CRB_SM_CRB || sm == CRB_SM_CRB_WITH_ACPI_START || + !strcmp(acpi_device_hid(device), "MSFT0101")) + priv->flags |= CRB_FL_CRB_START; + + if (sm == CRB_SM_ACPI_START || sm == CRB_SM_CRB_WITH_ACPI_START) + priv->flags |= CRB_FL_ACPI_START; + + priv->cca = (struct crb_control_area __iomem *) + devm_ioremap_nocache(dev, buf->control_area_pa, 0x1000); + if (!priv->cca) { + dev_err(dev, "ioremap of the control area failed\n"); + return -ENOMEM; + } + + memcpy_fromio(&pa, &priv->cca->cmd_pa, 8); + pa = le64_to_cpu(pa); + priv->cmd = devm_ioremap_nocache(dev, le64_to_cpu(pa), + ioread32(&priv->cca->cmd_size)); + if (!priv->cmd) { + dev_err(dev, "ioremap of the command buffer failed\n"); + return -ENOMEM; + } + + memcpy_fromio(&pa, &priv->cca->rsp_pa, 8); + pa = le64_to_cpu(pa); + priv->rsp = devm_ioremap_nocache(dev, le64_to_cpu(pa), + ioread32(&priv->cca->rsp_size)); + if (!priv->rsp) { + dev_err(dev, "ioremap of the response buffer failed\n"); + return -ENOMEM; + } + + chip->vendor.priv = priv; + + /* Default timeouts and durations */ + chip->vendor.timeout_a = msecs_to_jiffies(TPM2_TIMEOUT_A); + chip->vendor.timeout_b = msecs_to_jiffies(TPM2_TIMEOUT_B); + chip->vendor.timeout_c = msecs_to_jiffies(TPM2_TIMEOUT_C); + chip->vendor.timeout_d = msecs_to_jiffies(TPM2_TIMEOUT_D); + chip->vendor.duration[TPM_SHORT] = + msecs_to_jiffies(TPM2_DURATION_SHORT); + chip->vendor.duration[TPM_MEDIUM] = + msecs_to_jiffies(TPM2_DURATION_MEDIUM); + chip->vendor.duration[TPM_LONG] = + msecs_to_jiffies(TPM2_DURATION_LONG); + + chip->acpi_dev_handle = device->handle; + + rc = tpm2_do_selftest(chip); + if (rc) + return rc; + + return tpm_chip_register(chip); +} + +static int crb_acpi_remove(struct acpi_device *device) +{ + struct device *dev = &device->dev; + struct tpm_chip *chip = dev_get_drvdata(dev); + + tpm_chip_unregister(chip); + + if (chip->flags & TPM_CHIP_FLAG_TPM2) + tpm2_shutdown(chip, TPM2_SU_CLEAR); + + return 0; +} + +static struct acpi_device_id crb_device_ids[] = { + {"MSFT0101", 0}, + {"", 0}, +}; +MODULE_DEVICE_TABLE(acpi, crb_device_ids); + +static struct acpi_driver crb_acpi_driver = { + .name = "tpm_crb", + .ids = crb_device_ids, + .ops = { + .add = crb_acpi_add, + .remove = crb_acpi_remove, + }, + .drv = { + .pm = &crb_pm, + }, +}; + +module_acpi_driver(crb_acpi_driver); +MODULE_AUTHOR("Jarkko Sakkinen "); +MODULE_DESCRIPTION("TPM2 Driver"); +MODULE_VERSION("0.1"); +MODULE_LICENSE("GPL");