drivers/char/tpm/tpm_tis.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2005, 2006 IBM Corporation
   4  * Copyright (C) 2014, 2015 Intel Corporation
   5  *
   6  * Authors:
   7  * Leendert van Doorn <leendert@watson.ibm.com>
   8  * Kylene Hall <kjhall@us.ibm.com>
   9  *
  10  * Maintained by: <tpmdd-devel@lists.sourceforge.net>
  11  *
  12  * Device driver for TCG/TCPA TPM (trusted platform module).
  13  * Specifications at www.trustedcomputinggroup.org
  14  *
  15  * This device driver implements the TPM interface as defined in
  16  * the TCG TPM Interface Spec version 1.2, revision 1.0.
  17  */
  18 #include <linux/init.h>
  19 #include <linux/module.h>
  20 #include <linux/moduleparam.h>
  21 #include <linux/pnp.h>
  22 #include <linux/slab.h>
  23 #include <linux/interrupt.h>
  24 #include <linux/wait.h>
  25 #include <linux/acpi.h>
  26 #include <linux/freezer.h>
  27 #include <linux/of.h>
  28 #include <linux/of_device.h>
  29 #include <linux/kernel.h>
  30 #include "tpm.h"
  31 #include "tpm_tis_core.h"
  32
  33 struct tpm_info {
  34         struct resource res;
  35         /* irq > 0 means: use irq $irq;
  36          * irq = 0 means: autoprobe for an irq;
  37          * irq = -1 means: no irq support
  38          */
  39         int irq;
  40 };
  41
  42 struct tpm_tis_tcg_phy {
  43         struct tpm_tis_data priv;
  44         void __iomem *iobase;
  45 };
  46
  47 static inline struct tpm_tis_tcg_phy *to_tpm_tis_tcg_phy(struct tpm_tis_data *data)
  48 {
  49         return container_of(data, struct tpm_tis_tcg_phy, priv);
  50 }
  51
  52 static bool interrupts = true;
  53 module_param(interrupts, bool, 0444);
  54 MODULE_PARM_DESC(interrupts, "Enable interrupts");
  55
  56 static bool itpm;
  57 module_param(itpm, bool, 0444);
  58 MODULE_PARM_DESC(itpm, "Force iTPM workarounds (found on some Lenovo laptops)");
  59
  60 static bool force;
  61 #ifdef CONFIG_X86
  62 module_param(force, bool, 0444);
  63 MODULE_PARM_DESC(force, "Force device probe rather than using ACPI entry");
  64 #endif
  65
  66 #if defined(CONFIG_PNP) && defined(CONFIG_ACPI)
  67 static int has_hid(struct acpi_device *dev, const char *hid)
  68 {
  69         struct acpi_hardware_id *id;
  70
  71         list_for_each_entry(id, &dev->pnp.ids, list)
  72                 if (!strcmp(hid, id->id))
  73                         return 1;
  74
  75         return 0;
  76 }
  77
  78 static inline int is_itpm(struct acpi_device *dev)
  79 {
  80         if (!dev)
  81                 return 0;
  82         return has_hid(dev, "INTC0102");
  83 }
  84 #else
  85 static inline int is_itpm(struct acpi_device *dev)
  86 {
  87         return 0;
  88 }
  89 #endif
  90
  91 #if defined(CONFIG_ACPI)
  92 #define DEVICE_IS_TPM2 1
  93
  94 static const struct acpi_device_id tpm_acpi_tbl[] = {
  95         {"MSFT0101", DEVICE_IS_TPM2},
  96         {},
  97 };
  98 MODULE_DEVICE_TABLE(acpi, tpm_acpi_tbl);
  99
 100 static int check_acpi_tpm2(struct device *dev)
 101 {
 102         const struct acpi_device_id *aid = acpi_match_device(tpm_acpi_tbl, dev);
 103         struct acpi_table_tpm2 *tbl;
 104         acpi_status st;
 105
 106         if (!aid || aid->driver_data != DEVICE_IS_TPM2)
 107                 return 0;
 108
 109         /* If the ACPI TPM2 signature is matched then a global ACPI_SIG_TPM2
 110          * table is mandatory
 111          */
 112         st =
 113             acpi_get_table(ACPI_SIG_TPM2, 1, (struct acpi_table_header **)&tbl);
 114         if (ACPI_FAILURE(st) || tbl->header.length < sizeof(*tbl)) {
 115                 dev_err(dev, FW_BUG "failed to get TPM2 ACPI table\n");
 116                 return -EINVAL;
 117         }
 118
 119         /* The tpm2_crb driver handles this device */
 120         if (tbl->start_method != ACPI_TPM2_MEMORY_MAPPED)
 121                 return -ENODEV;
 122
 123         return 0;
 124 }
 125 #else
 126 static int check_acpi_tpm2(struct device *dev)
 127 {
 128         return 0;
 129 }
 130 #endif
 131
 132 static int tpm_tcg_read_bytes(struct tpm_tis_data *data, u32 addr, u16 len,
 133                               u8 *result)
 134 {
 135         struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 136
 137         while (len--)
 138                 *result++ = ioread8(phy->iobase + addr);
 139
 140         return 0;
 141 }
 142
 143 static int tpm_tcg_write_bytes(struct tpm_tis_data *data, u32 addr, u16 len,
 144                                const u8 *value)
 145 {
 146         struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 147
 148         while (len--)
 149                 iowrite8(*value++, phy->iobase + addr);
 150
 151         return 0;
 152 }
 153
 154 static int tpm_tcg_read16(struct tpm_tis_data *data, u32 addr, u16 *result)
 155 {
 156         struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 157
 158         *result = ioread16(phy->iobase + addr);
 159
 160         return 0;
 161 }
 162
 163 static int tpm_tcg_read32(struct tpm_tis_data *data, u32 addr, u32 *result)
 164 {
 165         struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 166
 167         *result = ioread32(phy->iobase + addr);
 168
 169         return 0;
 170 }
 171
 172 static int tpm_tcg_write32(struct tpm_tis_data *data, u32 addr, u32 value)
 173 {
 174         struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 175
 176         iowrite32(value, phy->iobase + addr);
 177
 178         return 0;
 179 }
 180
 181 static const struct tpm_tis_phy_ops tpm_tcg = {
 182         .read_bytes = tpm_tcg_read_bytes,
 183         .write_bytes = tpm_tcg_write_bytes,
 184         .read16 = tpm_tcg_read16,
 185         .read32 = tpm_tcg_read32,
 186         .write32 = tpm_tcg_write32,
 187 };
 188
 189 static int tpm_tis_init(struct device *dev, struct tpm_info *tpm_info)
 190 {
 191         struct tpm_tis_tcg_phy *phy;
 192         int irq = -1;
 193         int rc;
 194
 195         rc = check_acpi_tpm2(dev);
 196         if (rc)
 197                 return rc;
 198
 199         phy = devm_kzalloc(dev, sizeof(struct tpm_tis_tcg_phy), GFP_KERNEL);
 200         if (phy == NULL)
 201                 return -ENOMEM;
 202
 203         phy->iobase = devm_ioremap_resource(dev, &tpm_info->res);
 204         if (IS_ERR(phy->iobase))
 205                 return PTR_ERR(phy->iobase);
 206
 207         if (interrupts)
 208                 irq = tpm_info->irq;
 209
 210         if (itpm || is_itpm(ACPI_COMPANION(dev)))
 211                 phy->priv.flags |= TPM_TIS_ITPM_WORKAROUND;
 212
 213         return tpm_tis_core_init(dev, &phy->priv, irq, &tpm_tcg,
 214                                  ACPI_HANDLE(dev));
 215 }
 216
 217 static SIMPLE_DEV_PM_OPS(tpm_tis_pm, tpm_pm_suspend, tpm_tis_resume);
 218
 219 static int tpm_tis_pnp_init(struct pnp_dev *pnp_dev,
 220                             const struct pnp_device_id *pnp_id)
 221 {
 222         struct tpm_info tpm_info = {};
 223         struct resource *res;
 224
 225         res = pnp_get_resource(pnp_dev, IORESOURCE_MEM, 0);
 226         if (!res)
 227                 return -ENODEV;
 228         tpm_info.res = *res;
 229
 230         if (pnp_irq_valid(pnp_dev, 0))
 231                 tpm_info.irq = pnp_irq(pnp_dev, 0);
 232         else
 233                 tpm_info.irq = -1;
 234
 235         return tpm_tis_init(&pnp_dev->dev, &tpm_info);
 236 }
 237
 238 /*
 239  * There is a known bug caused by 93e1b7d42e1e ("[PATCH] tpm: add HID module
 240  * parameter"). This commit added IFX0102 device ID, which is also used by
 241  * tpm_infineon but ignored to add quirks to probe which driver ought to be
 242  * used.
 243  */
 244
 245 static struct pnp_device_id tpm_pnp_tbl[] = {
 246         {"PNP0C31", 0},         /* TPM */
 247         {"ATM1200", 0},         /* Atmel */
 248         {"IFX0102", 0},         /* Infineon */
 249         {"BCM0101", 0},         /* Broadcom */
 250         {"BCM0102", 0},         /* Broadcom */
 251         {"NSC1200", 0},         /* National */
 252         {"ICO0102", 0},         /* Intel */
 253         /* Add new here */
 254         {"", 0},                /* User Specified */
 255         {"", 0}                 /* Terminator */
 256 };
 257 MODULE_DEVICE_TABLE(pnp, tpm_pnp_tbl);
 258
 259 static void tpm_tis_pnp_remove(struct pnp_dev *dev)
 260 {
 261         struct tpm_chip *chip = pnp_get_drvdata(dev);
 262
 263         tpm_chip_unregister(chip);
 264         tpm_tis_remove(chip);
 265 }
 266
 267 static struct pnp_driver tis_pnp_driver = {
 268         .name = "tpm_tis",
 269         .id_table = tpm_pnp_tbl,
 270         .probe = tpm_tis_pnp_init,
 271         .remove = tpm_tis_pnp_remove,
 272         .driver = {
 273                 .pm = &tpm_tis_pm,
 274         },
 275 };
 276
 277 #define TIS_HID_USR_IDX (ARRAY_SIZE(tpm_pnp_tbl) - 2)
 278 module_param_string(hid, tpm_pnp_tbl[TIS_HID_USR_IDX].id,
 279                     sizeof(tpm_pnp_tbl[TIS_HID_USR_IDX].id), 0444);
 280 MODULE_PARM_DESC(hid, "Set additional specific HID for this driver to probe");
 281
 282 static struct platform_device *force_pdev;
 283
 284 static int tpm_tis_plat_probe(struct platform_device *pdev)
 285 {
 286         struct tpm_info tpm_info = {};
 287         struct resource *res;
 288
 289         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 290         if (res == NULL) {
 291                 dev_err(&pdev->dev, "no memory resource defined\n");
 292                 return -ENODEV;
 293         }
 294         tpm_info.res = *res;
 295
 296         tpm_info.irq = platform_get_irq_optional(pdev, 0);
 297         if (tpm_info.irq <= 0) {
 298                 if (pdev != force_pdev)
 299                         tpm_info.irq = -1;
 300                 else
 301                         /* When forcing auto probe the IRQ */
 302                         tpm_info.irq = 0;
 303         }
 304
 305         return tpm_tis_init(&pdev->dev, &tpm_info);
 306 }
 307
 308 static int tpm_tis_plat_remove(struct platform_device *pdev)
 309 {
 310         struct tpm_chip *chip = dev_get_drvdata(&pdev->dev);
 311
 312         tpm_chip_unregister(chip);
 313         tpm_tis_remove(chip);
 314
 315         return 0;
 316 }
 317
 318 #ifdef CONFIG_OF
 319 static const struct of_device_id tis_of_platform_match[] = {
 320         {.compatible = "tcg,tpm-tis-mmio"},
 321         {},
 322 };
 323 MODULE_DEVICE_TABLE(of, tis_of_platform_match);
 324 #endif
 325
 326 static struct platform_driver tis_drv = {
 327         .probe = tpm_tis_plat_probe,
 328         .remove = tpm_tis_plat_remove,
 329         .driver = {
 330                 .name           = "tpm_tis",
 331                 .pm             = &tpm_tis_pm,
 332                 .of_match_table = of_match_ptr(tis_of_platform_match),
 333                 .acpi_match_table = ACPI_PTR(tpm_acpi_tbl),
 334         },
 335 };
 336
 337 static int tpm_tis_force_device(void)
 338 {
 339         struct platform_device *pdev;
 340         static const struct resource x86_resources[] = {
 341                 {
 342                         .start = 0xFED40000,
 343                         .end = 0xFED40000 + TIS_MEM_LEN - 1,
 344                         .flags = IORESOURCE_MEM,
 345                 },
 346         };
 347
 348         if (!force)
 349                 return 0;
 350
 351         /* The driver core will match the name tpm_tis of the device to
 352          * the tpm_tis platform driver and complete the setup via
 353          * tpm_tis_plat_probe
 354          */
 355         pdev = platform_device_register_simple("tpm_tis", -1, x86_resources,
 356                                                ARRAY_SIZE(x86_resources));
 357         if (IS_ERR(pdev))
 358                 return PTR_ERR(pdev);
 359         force_pdev = pdev;
 360
 361         return 0;
 362 }
 363
 364 static int __init init_tis(void)
 365 {
 366         int rc;
 367
 368         rc = tpm_tis_force_device();
 369         if (rc)
 370                 goto err_force;
 371
 372         rc = platform_driver_register(&tis_drv);
 373         if (rc)
 374                 goto err_platform;
 375
 376
 377         if (IS_ENABLED(CONFIG_PNP)) {
 378                 rc = pnp_register_driver(&tis_pnp_driver);
 379                 if (rc)
 380                         goto err_pnp;
 381         }
 382
 383         return 0;
 384
 385 err_pnp:
 386         platform_driver_unregister(&tis_drv);
 387 err_platform:
 388         if (force_pdev)
 389                 platform_device_unregister(force_pdev);
 390 err_force:
 391         return rc;
 392 }
 393
 394 static void __exit cleanup_tis(void)
 395 {
 396         pnp_unregister_driver(&tis_pnp_driver);
 397         platform_driver_unregister(&tis_drv);
 398
 399         if (force_pdev)
 400                 platform_device_unregister(force_pdev);
 401 }
 402
 403 module_init(init_tis);
 404 module_exit(cleanup_tis);
 405 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
 406 MODULE_DESCRIPTION("TPM Driver");
 407 MODULE_VERSION("2.0");
 408 MODULE_LICENSE("GPL");