diff options
Diffstat (limited to 'drivers/char/tpm/tpm_tis.c')
-rw-r--r-- | drivers/char/tpm/tpm_tis.c | 434 |
1 files changed, 434 insertions, 0 deletions
diff --git a/drivers/char/tpm/tpm_tis.c b/drivers/char/tpm/tpm_tis.c new file mode 100644 index 0000000000..2c52b7905b --- /dev/null +++ b/drivers/char/tpm/tpm_tis.c @@ -0,0 +1,434 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2005, 2006 IBM Corporation + * Copyright (C) 2014, 2015 Intel Corporation + * + * Authors: + * Leendert van Doorn <leendert@watson.ibm.com> + * Kylene Hall <kjhall@us.ibm.com> + * + * Maintained by: <tpmdd-devel@lists.sourceforge.net> + * + * Device driver for TCG/TCPA TPM (trusted platform module). + * Specifications at www.trustedcomputinggroup.org + * + * This device driver implements the TPM interface as defined in + * the TCG TPM Interface Spec version 1.2, revision 1.0. + */ +#include <linux/init.h> +#include <linux/module.h> +#include <linux/moduleparam.h> +#include <linux/pnp.h> +#include <linux/slab.h> +#include <linux/interrupt.h> +#include <linux/wait.h> +#include <linux/acpi.h> +#include <linux/freezer.h> +#include <linux/of.h> +#include <linux/kernel.h> +#include "tpm.h" +#include "tpm_tis_core.h" + +struct tpm_info { + struct resource res; + /* irq > 0 means: use irq $irq; + * irq = 0 means: autoprobe for an irq; + * irq = -1 means: no irq support + */ + int irq; +}; + +struct tpm_tis_tcg_phy { + struct tpm_tis_data priv; + void __iomem *iobase; +}; + +static inline struct tpm_tis_tcg_phy *to_tpm_tis_tcg_phy(struct tpm_tis_data *data) +{ + return container_of(data, struct tpm_tis_tcg_phy, priv); +} + +#ifdef CONFIG_PREEMPT_RT +/* + * Flush previous write operations with a dummy read operation to the + * TPM MMIO base address. + */ +static inline void tpm_tis_flush(void __iomem *iobase) +{ + ioread8(iobase + TPM_ACCESS(0)); +} +#else +#define tpm_tis_flush(iobase) do { } while (0) +#endif + +/* + * Write a byte word to the TPM MMIO address, and flush the write queue. + * The flush ensures that the data is sent immediately over the bus and not + * aggregated with further requests and transferred later in a batch. The large + * write requests can lead to unwanted latency spikes by blocking the CPU until + * the complete batch has been transferred. + */ +static inline void tpm_tis_iowrite8(u8 b, void __iomem *iobase, u32 addr) +{ + iowrite8(b, iobase + addr); + tpm_tis_flush(iobase); +} + +/* + * Write a 32-bit word to the TPM MMIO address, and flush the write queue. + * The flush ensures that the data is sent immediately over the bus and not + * aggregated with further requests and transferred later in a batch. The large + * write requests can lead to unwanted latency spikes by blocking the CPU until + * the complete batch has been transferred. + */ +static inline void tpm_tis_iowrite32(u32 b, void __iomem *iobase, u32 addr) +{ + iowrite32(b, iobase + addr); + tpm_tis_flush(iobase); +} + +static bool interrupts; +module_param(interrupts, bool, 0444); +MODULE_PARM_DESC(interrupts, "Enable interrupts"); + +static bool itpm; +module_param(itpm, bool, 0444); +MODULE_PARM_DESC(itpm, "Force iTPM workarounds (found on some Lenovo laptops)"); + +static bool force; +#ifdef CONFIG_X86 +module_param(force, bool, 0444); +MODULE_PARM_DESC(force, "Force device probe rather than using ACPI entry"); +#endif + +#if defined(CONFIG_PNP) && defined(CONFIG_ACPI) +static int has_hid(struct acpi_device *dev, const char *hid) +{ + struct acpi_hardware_id *id; + + list_for_each_entry(id, &dev->pnp.ids, list) + if (!strcmp(hid, id->id)) + return 1; + + return 0; +} + +static inline int is_itpm(struct acpi_device *dev) +{ + if (!dev) + return 0; + return has_hid(dev, "INTC0102"); +} +#else +static inline int is_itpm(struct acpi_device *dev) +{ + return 0; +} +#endif + +#if defined(CONFIG_ACPI) +#define DEVICE_IS_TPM2 1 + +static const struct acpi_device_id tpm_acpi_tbl[] = { + {"MSFT0101", DEVICE_IS_TPM2}, + {}, +}; +MODULE_DEVICE_TABLE(acpi, tpm_acpi_tbl); + +static int check_acpi_tpm2(struct device *dev) +{ + const struct acpi_device_id *aid = acpi_match_device(tpm_acpi_tbl, dev); + struct acpi_table_tpm2 *tbl; + acpi_status st; + int ret = 0; + + if (!aid || aid->driver_data != DEVICE_IS_TPM2) + return 0; + + /* If the ACPI TPM2 signature is matched then a global ACPI_SIG_TPM2 + * table is mandatory + */ + st = acpi_get_table(ACPI_SIG_TPM2, 1, (struct acpi_table_header **)&tbl); + if (ACPI_FAILURE(st) || tbl->header.length < sizeof(*tbl)) { + dev_err(dev, FW_BUG "failed to get TPM2 ACPI table\n"); + return -EINVAL; + } + + /* The tpm2_crb driver handles this device */ + if (tbl->start_method != ACPI_TPM2_MEMORY_MAPPED) + ret = -ENODEV; + + acpi_put_table((struct acpi_table_header *)tbl); + return ret; +} +#else +static int check_acpi_tpm2(struct device *dev) +{ + return 0; +} +#endif + +static int tpm_tcg_read_bytes(struct tpm_tis_data *data, u32 addr, u16 len, + u8 *result, enum tpm_tis_io_mode io_mode) +{ + struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data); + __le16 result_le16; + __le32 result_le32; + + switch (io_mode) { + case TPM_TIS_PHYS_8: + while (len--) + *result++ = ioread8(phy->iobase + addr); + break; + case TPM_TIS_PHYS_16: + result_le16 = cpu_to_le16(ioread16(phy->iobase + addr)); + memcpy(result, &result_le16, sizeof(u16)); + break; + case TPM_TIS_PHYS_32: + result_le32 = cpu_to_le32(ioread32(phy->iobase + addr)); + memcpy(result, &result_le32, sizeof(u32)); + break; + } + + return 0; +} + +static int tpm_tcg_write_bytes(struct tpm_tis_data *data, u32 addr, u16 len, + const u8 *value, enum tpm_tis_io_mode io_mode) +{ + struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data); + + switch (io_mode) { + case TPM_TIS_PHYS_8: + while (len--) + tpm_tis_iowrite8(*value++, phy->iobase, addr); + break; + case TPM_TIS_PHYS_16: + return -EINVAL; + case TPM_TIS_PHYS_32: + tpm_tis_iowrite32(le32_to_cpu(*((__le32 *)value)), phy->iobase, addr); + break; + } + + return 0; +} + +static const struct tpm_tis_phy_ops tpm_tcg = { + .read_bytes = tpm_tcg_read_bytes, + .write_bytes = tpm_tcg_write_bytes, +}; + +static int tpm_tis_init(struct device *dev, struct tpm_info *tpm_info) +{ + struct tpm_tis_tcg_phy *phy; + int irq = -1; + int rc; + + rc = check_acpi_tpm2(dev); + if (rc) + return rc; + + phy = devm_kzalloc(dev, sizeof(struct tpm_tis_tcg_phy), GFP_KERNEL); + if (phy == NULL) + return -ENOMEM; + + phy->iobase = devm_ioremap_resource(dev, &tpm_info->res); + if (IS_ERR(phy->iobase)) + return PTR_ERR(phy->iobase); + + if (interrupts) + irq = tpm_info->irq; + + if (itpm || is_itpm(ACPI_COMPANION(dev))) + set_bit(TPM_TIS_ITPM_WORKAROUND, &phy->priv.flags); + + return tpm_tis_core_init(dev, &phy->priv, irq, &tpm_tcg, + ACPI_HANDLE(dev)); +} + +static SIMPLE_DEV_PM_OPS(tpm_tis_pm, tpm_pm_suspend, tpm_tis_resume); + +static int tpm_tis_pnp_init(struct pnp_dev *pnp_dev, + const struct pnp_device_id *pnp_id) +{ + struct tpm_info tpm_info = {}; + struct resource *res; + + res = pnp_get_resource(pnp_dev, IORESOURCE_MEM, 0); + if (!res) + return -ENODEV; + tpm_info.res = *res; + + if (pnp_irq_valid(pnp_dev, 0)) + tpm_info.irq = pnp_irq(pnp_dev, 0); + else + tpm_info.irq = -1; + + return tpm_tis_init(&pnp_dev->dev, &tpm_info); +} + +/* + * There is a known bug caused by 93e1b7d42e1e ("[PATCH] tpm: add HID module + * parameter"). This commit added IFX0102 device ID, which is also used by + * tpm_infineon but ignored to add quirks to probe which driver ought to be + * used. + */ + +static struct pnp_device_id tpm_pnp_tbl[] = { + {"PNP0C31", 0}, /* TPM */ + {"ATM1200", 0}, /* Atmel */ + {"IFX0102", 0}, /* Infineon */ + {"BCM0101", 0}, /* Broadcom */ + {"BCM0102", 0}, /* Broadcom */ + {"NSC1200", 0}, /* National */ + {"ICO0102", 0}, /* Intel */ + /* Add new here */ + {"", 0}, /* User Specified */ + {"", 0} /* Terminator */ +}; +MODULE_DEVICE_TABLE(pnp, tpm_pnp_tbl); + +static void tpm_tis_pnp_remove(struct pnp_dev *dev) +{ + struct tpm_chip *chip = pnp_get_drvdata(dev); + + tpm_chip_unregister(chip); + tpm_tis_remove(chip); +} + +static struct pnp_driver tis_pnp_driver = { + .name = "tpm_tis", + .id_table = tpm_pnp_tbl, + .probe = tpm_tis_pnp_init, + .remove = tpm_tis_pnp_remove, + .driver = { + .pm = &tpm_tis_pm, + }, +}; + +#define TIS_HID_USR_IDX (ARRAY_SIZE(tpm_pnp_tbl) - 2) +module_param_string(hid, tpm_pnp_tbl[TIS_HID_USR_IDX].id, + sizeof(tpm_pnp_tbl[TIS_HID_USR_IDX].id), 0444); +MODULE_PARM_DESC(hid, "Set additional specific HID for this driver to probe"); + +static struct platform_device *force_pdev; + +static int tpm_tis_plat_probe(struct platform_device *pdev) +{ + struct tpm_info tpm_info = {}; + struct resource *res; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (res == NULL) { + dev_err(&pdev->dev, "no memory resource defined\n"); + return -ENODEV; + } + tpm_info.res = *res; + + tpm_info.irq = platform_get_irq_optional(pdev, 0); + if (tpm_info.irq <= 0) { + if (pdev != force_pdev) + tpm_info.irq = -1; + else + /* When forcing auto probe the IRQ */ + tpm_info.irq = 0; + } + + return tpm_tis_init(&pdev->dev, &tpm_info); +} + +static void tpm_tis_plat_remove(struct platform_device *pdev) +{ + struct tpm_chip *chip = dev_get_drvdata(&pdev->dev); + + tpm_chip_unregister(chip); + tpm_tis_remove(chip); +} + +#ifdef CONFIG_OF +static const struct of_device_id tis_of_platform_match[] = { + {.compatible = "tcg,tpm-tis-mmio"}, + {}, +}; +MODULE_DEVICE_TABLE(of, tis_of_platform_match); +#endif + +static struct platform_driver tis_drv = { + .probe = tpm_tis_plat_probe, + .remove_new = tpm_tis_plat_remove, + .driver = { + .name = "tpm_tis", + .pm = &tpm_tis_pm, + .of_match_table = of_match_ptr(tis_of_platform_match), + .acpi_match_table = ACPI_PTR(tpm_acpi_tbl), + }, +}; + +static int tpm_tis_force_device(void) +{ + struct platform_device *pdev; + static const struct resource x86_resources[] = { + DEFINE_RES_MEM(0xFED40000, TIS_MEM_LEN) + }; + + if (!force) + return 0; + + /* The driver core will match the name tpm_tis of the device to + * the tpm_tis platform driver and complete the setup via + * tpm_tis_plat_probe + */ + pdev = platform_device_register_simple("tpm_tis", -1, x86_resources, + ARRAY_SIZE(x86_resources)); + if (IS_ERR(pdev)) + return PTR_ERR(pdev); + force_pdev = pdev; + + return 0; +} + +static int __init init_tis(void) +{ + int rc; + + rc = tpm_tis_force_device(); + if (rc) + goto err_force; + + rc = platform_driver_register(&tis_drv); + if (rc) + goto err_platform; + + + if (IS_ENABLED(CONFIG_PNP)) { + rc = pnp_register_driver(&tis_pnp_driver); + if (rc) + goto err_pnp; + } + + return 0; + +err_pnp: + platform_driver_unregister(&tis_drv); +err_platform: + if (force_pdev) + platform_device_unregister(force_pdev); +err_force: + return rc; +} + +static void __exit cleanup_tis(void) +{ + pnp_unregister_driver(&tis_pnp_driver); + platform_driver_unregister(&tis_drv); + + if (force_pdev) + platform_device_unregister(force_pdev); +} + +module_init(init_tis); +module_exit(cleanup_tis); +MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)"); +MODULE_DESCRIPTION("TPM Driver"); +MODULE_VERSION("2.0"); +MODULE_LICENSE("GPL"); |