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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /drivers/char/tpm/tpm_crb.c | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/char/tpm/tpm_crb.c')
-rw-r--r-- | drivers/char/tpm/tpm_crb.c | 858 |
1 files changed, 858 insertions, 0 deletions
diff --git a/drivers/char/tpm/tpm_crb.c b/drivers/char/tpm/tpm_crb.c new file mode 100644 index 0000000000..ea085b14ab --- /dev/null +++ b/drivers/char/tpm/tpm_crb.c @@ -0,0 +1,858 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2014 Intel Corporation + * + * Authors: + * Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> + * + * Maintained by: <tpmdd-devel@lists.sourceforge.net> + * + * This device driver implements the TPM interface as defined in + * the TCG CRB 2.0 TPM specification. + */ + +#include <linux/acpi.h> +#include <linux/highmem.h> +#include <linux/rculist.h> +#include <linux/module.h> +#include <linux/pm_runtime.h> +#ifdef CONFIG_ARM64 +#include <linux/arm-smccc.h> +#endif +#include "tpm.h" + +#define ACPI_SIG_TPM2 "TPM2" +#define TPM_CRB_MAX_RESOURCES 3 + +static const guid_t crb_acpi_start_guid = + GUID_INIT(0x6BBF6CAB, 0x5463, 0x4714, + 0xB7, 0xCD, 0xF0, 0x20, 0x3C, 0x03, 0x68, 0xD4); + +enum crb_defaults { + CRB_ACPI_START_REVISION_ID = 1, + CRB_ACPI_START_INDEX = 1, +}; + +enum crb_loc_ctrl { + CRB_LOC_CTRL_REQUEST_ACCESS = BIT(0), + CRB_LOC_CTRL_RELINQUISH = BIT(1), +}; + +enum crb_loc_state { + CRB_LOC_STATE_LOC_ASSIGNED = BIT(1), + CRB_LOC_STATE_TPM_REG_VALID_STS = BIT(7), +}; + +enum crb_ctrl_req { + CRB_CTRL_REQ_CMD_READY = BIT(0), + CRB_CTRL_REQ_GO_IDLE = BIT(1), +}; + +enum crb_ctrl_sts { + CRB_CTRL_STS_ERROR = BIT(0), + CRB_CTRL_STS_TPM_IDLE = BIT(1), +}; + +enum crb_start { + CRB_START_INVOKE = BIT(0), +}; + +enum crb_cancel { + CRB_CANCEL_INVOKE = BIT(0), +}; + +struct crb_regs_head { + u32 loc_state; + u32 reserved1; + u32 loc_ctrl; + u32 loc_sts; + u8 reserved2[32]; + u64 intf_id; + u64 ctrl_ext; +} __packed; + +struct crb_regs_tail { + u32 ctrl_req; + u32 ctrl_sts; + u32 ctrl_cancel; + u32 ctrl_start; + u32 ctrl_int_enable; + u32 ctrl_int_sts; + u32 ctrl_cmd_size; + u32 ctrl_cmd_pa_low; + u32 ctrl_cmd_pa_high; + u32 ctrl_rsp_size; + u64 ctrl_rsp_pa; +} __packed; + +enum crb_status { + CRB_DRV_STS_COMPLETE = BIT(0), +}; + +struct crb_priv { + u32 sm; + const char *hid; + struct crb_regs_head __iomem *regs_h; + struct crb_regs_tail __iomem *regs_t; + u8 __iomem *cmd; + u8 __iomem *rsp; + u32 cmd_size; + u32 smc_func_id; + u32 __iomem *pluton_start_addr; + u32 __iomem *pluton_reply_addr; +}; + +struct tpm2_crb_smc { + u32 interrupt; + u8 interrupt_flags; + u8 op_flags; + u16 reserved2; + u32 smc_func_id; +}; + +struct tpm2_crb_pluton { + u64 start_addr; + u64 reply_addr; +}; + +static bool crb_wait_for_reg_32(u32 __iomem *reg, u32 mask, u32 value, + unsigned long timeout) +{ + ktime_t start; + ktime_t stop; + + start = ktime_get(); + stop = ktime_add(start, ms_to_ktime(timeout)); + + do { + if ((ioread32(reg) & mask) == value) + return true; + + usleep_range(50, 100); + } while (ktime_before(ktime_get(), stop)); + + return ((ioread32(reg) & mask) == value); +} + +static int crb_try_pluton_doorbell(struct crb_priv *priv, bool wait_for_complete) +{ + if (priv->sm != ACPI_TPM2_COMMAND_BUFFER_WITH_PLUTON) + return 0; + + if (!crb_wait_for_reg_32(priv->pluton_reply_addr, ~0, 1, TPM2_TIMEOUT_C)) + return -ETIME; + + iowrite32(1, priv->pluton_start_addr); + if (wait_for_complete == false) + return 0; + + if (!crb_wait_for_reg_32(priv->pluton_start_addr, + 0xffffffff, 0, 200)) + return -ETIME; + + return 0; +} + +/** + * __crb_go_idle - request tpm crb device to go the idle state + * + * @dev: crb device + * @priv: crb private data + * + * Write CRB_CTRL_REQ_GO_IDLE to TPM_CRB_CTRL_REQ + * The device should respond within TIMEOUT_C by clearing the bit. + * Anyhow, we do not wait here as a consequent CMD_READY request + * will be handled correctly even if idle was not completed. + * + * The function does nothing for devices with ACPI-start method + * or SMC-start method. + * + * Return: 0 always + */ +static int __crb_go_idle(struct device *dev, struct crb_priv *priv) +{ + int rc; + + if ((priv->sm == ACPI_TPM2_START_METHOD) || + (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD) || + (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC)) + return 0; + + iowrite32(CRB_CTRL_REQ_GO_IDLE, &priv->regs_t->ctrl_req); + + rc = crb_try_pluton_doorbell(priv, true); + if (rc) + return rc; + + if (!crb_wait_for_reg_32(&priv->regs_t->ctrl_req, + CRB_CTRL_REQ_GO_IDLE/* mask */, + 0, /* value */ + TPM2_TIMEOUT_C)) { + dev_warn(dev, "goIdle timed out\n"); + return -ETIME; + } + + return 0; +} + +static int crb_go_idle(struct tpm_chip *chip) +{ + struct device *dev = &chip->dev; + struct crb_priv *priv = dev_get_drvdata(dev); + + return __crb_go_idle(dev, priv); +} + +/** + * __crb_cmd_ready - request tpm crb device to enter ready state + * + * @dev: crb device + * @priv: crb private data + * + * Write CRB_CTRL_REQ_CMD_READY to TPM_CRB_CTRL_REQ + * and poll till the device acknowledge it by clearing the bit. + * The device should respond within TIMEOUT_C. + * + * The function does nothing for devices with ACPI-start method + * or SMC-start method. + * + * Return: 0 on success -ETIME on timeout; + */ +static int __crb_cmd_ready(struct device *dev, struct crb_priv *priv) +{ + int rc; + + if ((priv->sm == ACPI_TPM2_START_METHOD) || + (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD) || + (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC)) + return 0; + + iowrite32(CRB_CTRL_REQ_CMD_READY, &priv->regs_t->ctrl_req); + + rc = crb_try_pluton_doorbell(priv, true); + if (rc) + return rc; + + if (!crb_wait_for_reg_32(&priv->regs_t->ctrl_req, + CRB_CTRL_REQ_CMD_READY /* mask */, + 0, /* value */ + TPM2_TIMEOUT_C)) { + dev_warn(dev, "cmdReady timed out\n"); + return -ETIME; + } + + return 0; +} + +static int crb_cmd_ready(struct tpm_chip *chip) +{ + struct device *dev = &chip->dev; + struct crb_priv *priv = dev_get_drvdata(dev); + + return __crb_cmd_ready(dev, priv); +} + +static int __crb_request_locality(struct device *dev, + struct crb_priv *priv, int loc) +{ + u32 value = CRB_LOC_STATE_LOC_ASSIGNED | + CRB_LOC_STATE_TPM_REG_VALID_STS; + + if (!priv->regs_h) + return 0; + + iowrite32(CRB_LOC_CTRL_REQUEST_ACCESS, &priv->regs_h->loc_ctrl); + if (!crb_wait_for_reg_32(&priv->regs_h->loc_state, value, value, + TPM2_TIMEOUT_C)) { + dev_warn(dev, "TPM_LOC_STATE_x.requestAccess timed out\n"); + return -ETIME; + } + + return 0; +} + +static int crb_request_locality(struct tpm_chip *chip, int loc) +{ + struct crb_priv *priv = dev_get_drvdata(&chip->dev); + + return __crb_request_locality(&chip->dev, priv, loc); +} + +static int __crb_relinquish_locality(struct device *dev, + struct crb_priv *priv, int loc) +{ + u32 mask = CRB_LOC_STATE_LOC_ASSIGNED | + CRB_LOC_STATE_TPM_REG_VALID_STS; + u32 value = CRB_LOC_STATE_TPM_REG_VALID_STS; + + if (!priv->regs_h) + return 0; + + iowrite32(CRB_LOC_CTRL_RELINQUISH, &priv->regs_h->loc_ctrl); + if (!crb_wait_for_reg_32(&priv->regs_h->loc_state, mask, value, + TPM2_TIMEOUT_C)) { + dev_warn(dev, "TPM_LOC_STATE_x.Relinquish timed out\n"); + return -ETIME; + } + + return 0; +} + +static int crb_relinquish_locality(struct tpm_chip *chip, int loc) +{ + struct crb_priv *priv = dev_get_drvdata(&chip->dev); + + return __crb_relinquish_locality(&chip->dev, priv, loc); +} + +static u8 crb_status(struct tpm_chip *chip) +{ + struct crb_priv *priv = dev_get_drvdata(&chip->dev); + u8 sts = 0; + + if ((ioread32(&priv->regs_t->ctrl_start) & CRB_START_INVOKE) != + CRB_START_INVOKE) + sts |= CRB_DRV_STS_COMPLETE; + + return sts; +} + +static int crb_recv(struct tpm_chip *chip, u8 *buf, size_t count) +{ + struct crb_priv *priv = dev_get_drvdata(&chip->dev); + unsigned int expected; + + /* A sanity check that the upper layer wants to get at least the header + * as that is the minimum size for any TPM response. + */ + if (count < TPM_HEADER_SIZE) + return -EIO; + + /* If this bit is set, according to the spec, the TPM is in + * unrecoverable condition. + */ + if (ioread32(&priv->regs_t->ctrl_sts) & CRB_CTRL_STS_ERROR) + return -EIO; + + /* Read the first 8 bytes in order to get the length of the response. + * We read exactly a quad word in order to make sure that the remaining + * reads will be aligned. + */ + memcpy_fromio(buf, priv->rsp, 8); + + expected = be32_to_cpup((__be32 *)&buf[2]); + if (expected > count || expected < TPM_HEADER_SIZE) + return -EIO; + + memcpy_fromio(&buf[8], &priv->rsp[8], expected - 8); + + 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_guid, + 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; +} + +#ifdef CONFIG_ARM64 +/* + * This is a TPM Command Response Buffer start method that invokes a + * Secure Monitor Call to requrest the firmware to execute or cancel + * a TPM 2.0 command. + */ +static int tpm_crb_smc_start(struct device *dev, unsigned long func_id) +{ + struct arm_smccc_res res; + + arm_smccc_smc(func_id, 0, 0, 0, 0, 0, 0, 0, &res); + if (res.a0 != 0) { + dev_err(dev, + FW_BUG "tpm_crb_smc_start() returns res.a0 = 0x%lx\n", + res.a0); + return -EIO; + } + + return 0; +} +#else +static int tpm_crb_smc_start(struct device *dev, unsigned long func_id) +{ + dev_err(dev, FW_BUG "tpm_crb: incorrect start method\n"); + return -EINVAL; +} +#endif + +static int crb_send(struct tpm_chip *chip, u8 *buf, size_t len) +{ + struct crb_priv *priv = dev_get_drvdata(&chip->dev); + int rc = 0; + + /* Zero the cancel register so that the next command will not get + * canceled. + */ + iowrite32(0, &priv->regs_t->ctrl_cancel); + + if (len > priv->cmd_size) { + dev_err(&chip->dev, "invalid command count value %zd %d\n", + len, priv->cmd_size); + return -E2BIG; + } + + /* Seems to be necessary for every command */ + if (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_PLUTON) + __crb_cmd_ready(&chip->dev, priv); + + memcpy_toio(priv->cmd, buf, len); + + /* Make sure that cmd is populated before issuing start. */ + wmb(); + + /* 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 + * CRB start, hence invoking CRB start method if hid == MSFT0101. + */ + if ((priv->sm == ACPI_TPM2_COMMAND_BUFFER) || + (priv->sm == ACPI_TPM2_MEMORY_MAPPED) || + (!strcmp(priv->hid, "MSFT0101"))) + iowrite32(CRB_START_INVOKE, &priv->regs_t->ctrl_start); + + if ((priv->sm == ACPI_TPM2_START_METHOD) || + (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD)) + rc = crb_do_acpi_start(chip); + + if (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC) { + iowrite32(CRB_START_INVOKE, &priv->regs_t->ctrl_start); + rc = tpm_crb_smc_start(&chip->dev, priv->smc_func_id); + } + + if (rc) + return rc; + + return crb_try_pluton_doorbell(priv, false); +} + +static void crb_cancel(struct tpm_chip *chip) +{ + struct crb_priv *priv = dev_get_drvdata(&chip->dev); + + iowrite32(CRB_CANCEL_INVOKE, &priv->regs_t->ctrl_cancel); + + if (((priv->sm == ACPI_TPM2_START_METHOD) || + (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD)) && + crb_do_acpi_start(chip)) + dev_err(&chip->dev, "ACPI Start failed\n"); +} + +static bool crb_req_canceled(struct tpm_chip *chip, u8 status) +{ + struct crb_priv *priv = dev_get_drvdata(&chip->dev); + u32 cancel = ioread32(&priv->regs_t->ctrl_cancel); + + return (cancel & CRB_CANCEL_INVOKE) == CRB_CANCEL_INVOKE; +} + +static const struct tpm_class_ops tpm_crb = { + .flags = TPM_OPS_AUTO_STARTUP, + .status = crb_status, + .recv = crb_recv, + .send = crb_send, + .cancel = crb_cancel, + .req_canceled = crb_req_canceled, + .go_idle = crb_go_idle, + .cmd_ready = crb_cmd_ready, + .request_locality = crb_request_locality, + .relinquish_locality = crb_relinquish_locality, + .req_complete_mask = CRB_DRV_STS_COMPLETE, + .req_complete_val = CRB_DRV_STS_COMPLETE, +}; + +static int crb_check_resource(struct acpi_resource *ares, void *data) +{ + struct resource *iores_array = data; + struct resource_win win; + struct resource *res = &(win.res); + int i; + + if (acpi_dev_resource_memory(ares, res) || + acpi_dev_resource_address_space(ares, &win)) { + for (i = 0; i < TPM_CRB_MAX_RESOURCES + 1; ++i) { + if (resource_type(iores_array + i) != IORESOURCE_MEM) { + iores_array[i] = *res; + iores_array[i].name = NULL; + break; + } + } + } + + return 1; +} + +static void __iomem *crb_map_res(struct device *dev, struct resource *iores, + void __iomem **iobase_ptr, u64 start, u32 size) +{ + struct resource new_res = { + .start = start, + .end = start + size - 1, + .flags = IORESOURCE_MEM, + }; + + /* Detect a 64 bit address on a 32 bit system */ + if (start != new_res.start) + return IOMEM_ERR_PTR(-EINVAL); + + if (!iores) + return devm_ioremap_resource(dev, &new_res); + + if (!*iobase_ptr) { + *iobase_ptr = devm_ioremap_resource(dev, iores); + if (IS_ERR(*iobase_ptr)) + return *iobase_ptr; + } + + return *iobase_ptr + (new_res.start - iores->start); +} + +/* + * Work around broken BIOSs that return inconsistent values from the ACPI + * region vs the registers. Trust the ACPI region. Such broken systems + * probably cannot send large TPM commands since the buffer will be truncated. + */ +static u64 crb_fixup_cmd_size(struct device *dev, struct resource *io_res, + u64 start, u64 size) +{ + if (io_res->start > start || io_res->end < start) + return size; + + if (start + size - 1 <= io_res->end) + return size; + + dev_err(dev, + FW_BUG "ACPI region does not cover the entire command/response buffer. %pr vs %llx %llx\n", + io_res, start, size); + + return io_res->end - start + 1; +} + +static int crb_map_io(struct acpi_device *device, struct crb_priv *priv, + struct acpi_table_tpm2 *buf) +{ + struct list_head acpi_resource_list; + struct resource iores_array[TPM_CRB_MAX_RESOURCES + 1] = { {0} }; + void __iomem *iobase_array[TPM_CRB_MAX_RESOURCES] = {NULL}; + struct device *dev = &device->dev; + struct resource *iores; + void __iomem **iobase_ptr; + int i; + u32 pa_high, pa_low; + u64 cmd_pa; + u32 cmd_size; + __le64 __rsp_pa; + u64 rsp_pa; + u32 rsp_size; + int ret; + + /* + * Pluton sometimes does not define ACPI memory regions. + * Mapping is then done in crb_map_pluton + */ + if (priv->sm != ACPI_TPM2_COMMAND_BUFFER_WITH_PLUTON) { + INIT_LIST_HEAD(&acpi_resource_list); + ret = acpi_dev_get_resources(device, &acpi_resource_list, + crb_check_resource, iores_array); + if (ret < 0) + return ret; + acpi_dev_free_resource_list(&acpi_resource_list); + + if (resource_type(iores_array) != IORESOURCE_MEM) { + dev_err(dev, FW_BUG "TPM2 ACPI table does not define a memory resource\n"); + return -EINVAL; + } else if (resource_type(iores_array + TPM_CRB_MAX_RESOURCES) == + IORESOURCE_MEM) { + dev_warn(dev, "TPM2 ACPI table defines too many memory resources\n"); + memset(iores_array + TPM_CRB_MAX_RESOURCES, + 0, sizeof(*iores_array)); + iores_array[TPM_CRB_MAX_RESOURCES].flags = 0; + } + } + + iores = NULL; + iobase_ptr = NULL; + for (i = 0; resource_type(iores_array + i) == IORESOURCE_MEM; ++i) { + if (buf->control_address >= iores_array[i].start && + buf->control_address + sizeof(struct crb_regs_tail) - 1 <= + iores_array[i].end) { + iores = iores_array + i; + iobase_ptr = iobase_array + i; + break; + } + } + + priv->regs_t = crb_map_res(dev, iores, iobase_ptr, buf->control_address, + sizeof(struct crb_regs_tail)); + + if (IS_ERR(priv->regs_t)) + return PTR_ERR(priv->regs_t); + + /* The ACPI IO region starts at the head area and continues to include + * the control area, as one nice sane region except for some older + * stuff that puts the control area outside the ACPI IO region. + */ + if ((priv->sm == ACPI_TPM2_COMMAND_BUFFER) || + (priv->sm == ACPI_TPM2_MEMORY_MAPPED)) { + if (iores && + buf->control_address == iores->start + + sizeof(*priv->regs_h)) + priv->regs_h = *iobase_ptr; + else + dev_warn(dev, FW_BUG "Bad ACPI memory layout"); + } + + ret = __crb_request_locality(dev, priv, 0); + if (ret) + return ret; + + /* + * PTT HW bug w/a: wake up the device to access + * possibly not retained registers. + */ + ret = __crb_cmd_ready(dev, priv); + if (ret) + goto out_relinquish_locality; + + pa_high = ioread32(&priv->regs_t->ctrl_cmd_pa_high); + pa_low = ioread32(&priv->regs_t->ctrl_cmd_pa_low); + cmd_pa = ((u64)pa_high << 32) | pa_low; + cmd_size = ioread32(&priv->regs_t->ctrl_cmd_size); + + iores = NULL; + iobase_ptr = NULL; + for (i = 0; iores_array[i].end; ++i) { + if (cmd_pa >= iores_array[i].start && + cmd_pa <= iores_array[i].end) { + iores = iores_array + i; + iobase_ptr = iobase_array + i; + break; + } + } + + if (iores) + cmd_size = crb_fixup_cmd_size(dev, iores, cmd_pa, cmd_size); + + dev_dbg(dev, "cmd_hi = %X cmd_low = %X cmd_size %X\n", + pa_high, pa_low, cmd_size); + + priv->cmd = crb_map_res(dev, iores, iobase_ptr, cmd_pa, cmd_size); + if (IS_ERR(priv->cmd)) { + ret = PTR_ERR(priv->cmd); + goto out; + } + + memcpy_fromio(&__rsp_pa, &priv->regs_t->ctrl_rsp_pa, 8); + rsp_pa = le64_to_cpu(__rsp_pa); + rsp_size = ioread32(&priv->regs_t->ctrl_rsp_size); + + iores = NULL; + iobase_ptr = NULL; + for (i = 0; resource_type(iores_array + i) == IORESOURCE_MEM; ++i) { + if (rsp_pa >= iores_array[i].start && + rsp_pa <= iores_array[i].end) { + iores = iores_array + i; + iobase_ptr = iobase_array + i; + break; + } + } + + if (iores) + rsp_size = crb_fixup_cmd_size(dev, iores, rsp_pa, rsp_size); + + if (cmd_pa != rsp_pa) { + priv->rsp = crb_map_res(dev, iores, iobase_ptr, + rsp_pa, rsp_size); + ret = PTR_ERR_OR_ZERO(priv->rsp); + goto out; + } + + /* According to the PTP specification, overlapping command and response + * buffer sizes must be identical. + */ + if (cmd_size != rsp_size) { + dev_err(dev, FW_BUG "overlapping command and response buffer sizes are not identical"); + ret = -EINVAL; + goto out; + } + + priv->rsp = priv->cmd; + +out: + if (!ret) + priv->cmd_size = cmd_size; + + __crb_go_idle(dev, priv); + +out_relinquish_locality: + + __crb_relinquish_locality(dev, priv, 0); + + return ret; +} + +static int crb_map_pluton(struct device *dev, struct crb_priv *priv, + struct acpi_table_tpm2 *buf, struct tpm2_crb_pluton *crb_pluton) +{ + priv->pluton_start_addr = crb_map_res(dev, NULL, NULL, + crb_pluton->start_addr, 4); + if (IS_ERR(priv->pluton_start_addr)) + return PTR_ERR(priv->pluton_start_addr); + + priv->pluton_reply_addr = crb_map_res(dev, NULL, NULL, + crb_pluton->reply_addr, 4); + if (IS_ERR(priv->pluton_reply_addr)) + return PTR_ERR(priv->pluton_reply_addr); + + return 0; +} + +static int crb_acpi_add(struct acpi_device *device) +{ + struct acpi_table_tpm2 *buf; + struct crb_priv *priv; + struct tpm_chip *chip; + struct device *dev = &device->dev; + struct tpm2_crb_smc *crb_smc; + struct tpm2_crb_pluton *crb_pluton; + acpi_status status; + u32 sm; + int rc; + + status = acpi_get_table(ACPI_SIG_TPM2, 1, + (struct acpi_table_header **) &buf); + if (ACPI_FAILURE(status) || buf->header.length < sizeof(*buf)) { + dev_err(dev, FW_BUG "failed to get TPM2 ACPI table\n"); + return -EINVAL; + } + + /* Should the FIFO driver handle this? */ + sm = buf->start_method; + if (sm == ACPI_TPM2_MEMORY_MAPPED) { + rc = -ENODEV; + goto out; + } + + priv = devm_kzalloc(dev, sizeof(struct crb_priv), GFP_KERNEL); + if (!priv) { + rc = -ENOMEM; + goto out; + } + + if (sm == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC) { + if (buf->header.length < (sizeof(*buf) + sizeof(*crb_smc))) { + dev_err(dev, + FW_BUG "TPM2 ACPI table has wrong size %u for start method type %d\n", + buf->header.length, + ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC); + rc = -EINVAL; + goto out; + } + crb_smc = ACPI_ADD_PTR(struct tpm2_crb_smc, buf, sizeof(*buf)); + priv->smc_func_id = crb_smc->smc_func_id; + } + + if (sm == ACPI_TPM2_COMMAND_BUFFER_WITH_PLUTON) { + if (buf->header.length < (sizeof(*buf) + sizeof(*crb_pluton))) { + dev_err(dev, + FW_BUG "TPM2 ACPI table has wrong size %u for start method type %d\n", + buf->header.length, + ACPI_TPM2_COMMAND_BUFFER_WITH_PLUTON); + rc = -EINVAL; + goto out; + } + crb_pluton = ACPI_ADD_PTR(struct tpm2_crb_pluton, buf, sizeof(*buf)); + rc = crb_map_pluton(dev, priv, buf, crb_pluton); + if (rc) + goto out; + } + + priv->sm = sm; + priv->hid = acpi_device_hid(device); + + rc = crb_map_io(device, priv, buf); + if (rc) + goto out; + + chip = tpmm_chip_alloc(dev, &tpm_crb); + if (IS_ERR(chip)) { + rc = PTR_ERR(chip); + goto out; + } + + dev_set_drvdata(&chip->dev, priv); + chip->acpi_dev_handle = device->handle; + chip->flags = TPM_CHIP_FLAG_TPM2; + + rc = tpm_chip_bootstrap(chip); + if (rc) + goto out; + +#ifdef CONFIG_X86 + /* A quirk for https://www.amd.com/en/support/kb/faq/pa-410 */ + if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD && + priv->sm != ACPI_TPM2_COMMAND_BUFFER_WITH_PLUTON) { + dev_info(dev, "Disabling hwrng\n"); + chip->flags |= TPM_CHIP_FLAG_HWRNG_DISABLED; + } +#endif /* CONFIG_X86 */ + + rc = tpm_chip_register(chip); + +out: + acpi_put_table((struct acpi_table_header *)buf); + return rc; +} + +static void crb_acpi_remove(struct acpi_device *device) +{ + struct device *dev = &device->dev; + struct tpm_chip *chip = dev_get_drvdata(dev); + + tpm_chip_unregister(chip); +} + +static const struct dev_pm_ops crb_pm = { + SET_SYSTEM_SLEEP_PM_OPS(tpm_pm_suspend, tpm_pm_resume) +}; + +static const 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 <jarkko.sakkinen@linux.intel.com>"); +MODULE_DESCRIPTION("TPM2 Driver"); +MODULE_VERSION("0.1"); +MODULE_LICENSE("GPL"); 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