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Diffstat (limited to 'drivers/char/tpm/tpm_tis.c')
-rw-r--r--drivers/char/tpm/tpm_tis.c434
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");